マスザワ トオル増澤 徹教授Toru MASUZAWA
■研究者基本情報
研究分野
経歴
委員歴
- 2023年10月 - 現在, 監事, 日本人工臓器学会
- 2021年11月 - 現在, 理事, アジア環太平洋人工臓器学会 理事
- 2004年06月 - 現在, 理事, ライフサポート学会
- 2000年05月 - 現在, 評議員, 日本人工臓器学会
- 1996年 - 現在, 「生体流体工学研究会」幹事, ライフサポート学会
- 2022年06月 - 2024年05月, 理事長, 日本AEM学会
- 2022年06月 - 2023年11月, 理事長, 国際機械式循環補助学会 理事長
- 2021年10月 - 2023年10月, 副理事長, 日本人工臓器学会 副理事長
- 2009年10月 - 2023年10月, 理事, 日本人工臓器学会
- 2012年04月 - 2022年05月, 表彰委員長, 日本AEM学会 表彰委員長
- 2013年11月 - 2021年10月, Secretary General, アジア環太平洋人工臓器学会 事務局長
- 2014年06月 - 2020年05月, 理事, 国際人工臓器連合
- 2014年04月 - 2020年03月, 連携会員, 日本学術会議
- 2011年04月 - 2020年03月, J-MACS有害事象判定委員会 委員, 医薬品医療機器総合機構
- 2018年01月01日 - 2019年12月31日, PRESIDENT, International Federation for Artificial Organs
- 2018年01月 - 2019年12月, 理事長, 国際人工臓器学会
- 2015年10月 - 2018年09月, 監事, 日本人工臓器学会
- 2016年06月01日 - 2018年05月31日, 副理事長, International Federation for Artificial Organs
- 2016年06月 - 2018年05月, 副理事長, International Federation for Artificial Organs
- 2016年01月 - 2017年12月, 副理事長, 国際人工臓器学会連盟 副理事長
- 2015年11月 - 2017年11月, 監事, 日本人工臓器学会 監事
- 2015年04月 - 2017年03月, 学会長, ライフサポート学会
- 2014年04月 - 2016年03月, NEDO 小型患者用補助人工心臓プロジェクト 開発委員会, NEDO
- 2014年06月 - 2015年12月, 理事, 国際人工臓器学会連盟 理事
- 2013年11月 - 2015年11月, 副理事長, 日本人工臓器学会 副理事長
- 2013年10月 - 2015年09月, 副理事長, 日本人工臓器学会
- 2012年04月 - 2015年03月, 医薬品医療機器総合機構専門委員, 医薬品医療機器総合機構
- 2011年04月 - 2014年03月, 専門別研究会会長「医用アクチュエーション研究会」, 日本生体医工学会
- 2013年09月28日, 事務局長, アジア太平洋人工臓器学会
- 2013年09月, 事務局長, アジア太平洋人工臓器学会
- 2012年04月 - 2013年03月, 磁気浮上技術調査専門委員会委員, 電気学会 磁気浮上技術調査専門委員会委員
- 2011年, 選奨部会部会長, ライフサポート学会
- 2009年, 国際担当理事, 日本人工臓器学会
- 2008年04月, 関東支部商議員, 日本機械学会
- 2008年, 理事, 日本AEM学会
- 2005年04月 - 2007年, 第48回日本生体医工学会大会プログラム委員長, 日本生体医工学会
- 2003年06月 - 2006年, 評議員, 日本生活支援工学会
- 2005年, 理事, 国際ロータリ血液ポンプ学会
- 2005年, リニアドライブ研究会 協同研究委員会 委員長, 電気学会
- 2001年12月 - 2003年03月, 78期 機械学会・運営委員、 代議員, 日本機械学会
- 1999年 - 2002年, プログラム委員, ライフサポート学会
- 2001年, 第79期 機械力学・計測制御部門 運営委員会、代議委員, 日本機械学会
- 2001年, 編集委員会委員, 日本人工臓器学会
- 2000年, 第38回日本人工臓器学会大会 プログラム委員, 日本人工臓器学会
- 1999年04月, 代議員, 日本生体医工学会
- 1997年, リニアドライブ研究会 協同研究委員会 各幹事, 電気学会
外部リンク
研究者からのメッセージ
(研究者からのメッセージ)
(研究経歴)
昭和62年3月東京電機大学大学院博士課程単位取得後満期退学.同年4月東京大学工学部精密機械工学科助手.その後、国立循環器病センタ-研究所人工臓器部室長を経て平成10年4月より茨城大学工学部機械工学科助教授.平成14年4月より同大学教授.医用工学、人工心臓の研究に従事.
■研究活動情報
受賞
- 2021年12月, 日本AEM学会技術賞, 小児用人工心臓のための超小型磁気浮上モータの改良, 日本AEM学会
増澤徹、長真啓
国内学会・会議・シンポジウム等の賞 - 2018年10月20日, 日本AEM学会論文賞, ダブルステータ型アキシャルギャップ磁気浮上モータの5軸制御方式を活用した小児用人工心臓循環補助時の外乱力推定と磁気浮上特性評価, 日本AEM学会
増澤徹;長真啓
学会誌・学術雑誌による顕彰 - 2018年10月, 日本AEM学会論文賞, ダブルステータ型アキシャルギャップ磁気浮上モータの5軸制御方式を活用した小児用人工心臓循環補助時の外乱力推定と磁気浮上特性評価, 日本AEM学会
増澤徹,長真啓
学会誌・学術雑誌による顕彰 - 2017年10月26日, 日本AEM学会論文賞, ラジアル型セルフベアリングモータにおける受動安定性の簡易推定式の検討, 日本AEM学会
増澤徹;小沼弘幸;村上倫子
国内学会・会議・シンポジウム等の賞 - 2017年10月, 日本AEM学会論文賞, ラジアル型セルフベアリングモータにおける受動安定性の簡易推定式の検討, 日本AEM学会
増澤徹,小沼弘幸.村上倫子
国内学会・会議・シンポジウム等の賞 - 2013年09月, 平成25年度日本人工臓器学会最優秀論文賞, 低レベル複合エネルギー生体組織接合への金属表面性状の影響, 日本人工臓器学会
青代敏行,増澤徹,尾関和秀,岸田晶夫,樋上哲哉 - 2011年11月, 平成23年度日本AEM学会技術賞, 治療用人工心臓のためのアキシャル型磁気浮上モータの開発,日本AEM学会誌Vol.19,No.2,2011, 日本AEM学会
- 2011年10月, 平成23年度茨城大学学長学術表彰優秀賞, 国立大学法人茨城大学
- 2010年11月, 平成22年度日本人工臓器学会最優秀論文賞, 非定常CFD解析による磁気浮上遠心ポンプにかかる流体力の推定, 日本人工臓器学会
増澤徹,太田晶子,田中伸厚,銭逸*,築谷朋典 - 2009年11月, 日本AEM学会功労賞, 日本AEM学会
増澤徹 - 2009年11月, Japanese Society for Artificial Organs SAITO AWARD 2008, Estimation of changes in dynamic hydraulic force in a magnetically suspended centrifugal blood pump with transient computational fluid dynamics analysis, 日本人工臓器学会
増澤徹 - 2007年11月, The International Society for Rotary Blood Pumps (ISRBP) Poster Award, Transient CFD analysis for a maglev centrifugal pump, The International Society for Rotary Blood Pumps (ISRBP)
Masuzawa T;Ohta A;Tanaka N;Qian Y;Tsukiya T - 2007年10月, ライフサポート学会論文賞, Development of a novel hybrid type magnetic bearing and application to small impeller centrifugal pump for artificial hearts, ライフサポート学会
Saito T;Masuzawa T;Nakayama N - 2006年, 日本人工臓器学会論文賞
- 2006年, ベストCFDグラフィック・アワード
- 2003年, ライフサポート学会論文賞
- 2001年, 日本人工臓器学会論文賞
- 2000年, 東京電機大学ME会第13回高橋賞
- 1996年, 日本機械学会設計工学・システム部門ラピッドプロトタイピングコンテストアイデア賞
- 1993年, 第21回人工心臓と補助循環懇話会 若手研究者最優秀賞
- 1992年, 第20回人工心臓と補助循環懇話会 若手研究者最優秀賞
- 1991年, 日本エム・イー学会論文賞
論文
- 〔主要な業績〕体内植込型全人工心臓のためのホモポーラ型磁気浮上モータ
鈴木修太、増澤徹、川口哲平、長真啓、北山文矢, 責任著者, 日本AEM学会
日本AEM学会誌, 2024年02月, [査読有り] - 〔主要な業績〕Flow Rate Estimation of a Centrifugal Blood Pump Using the Balance of Control Currents,Through the Electromagnets in the Magnetic Bearing
Shuya SHIDA; Toru MASUZAWA; Masahiro OSA; Yutaka SUZUKI, ラスト(シニア)オーサー, the Japanese Society for Medical and Biological Engineering
Advanced Biomedical Engineering, 2023年12月, [査読有り] - 〔主要な業績〕Effects of biventricular shunt on pump,characteristics in a maglev total artificial,heart
Shuya Shida; Kenichi Tsushima; Masahiro Osa; Daniel L Timms and Toru Masuzawa, ラスト(シニア)オーサー, ESAO
The International Journal of Artificial Organs, 2023年10月, [査読有り] - 磁気浮上人工心臓のための制御周波数の検討
斎藤広明,増澤徹,長真啓,北山文矢, 責任著者, 日本AEM学会
日本AEM学会誌, 2023年04月, [査読有り] - 人工心臓のためのMR流体トルク伝達機構
北山文矢,増澤徹,長真啓,佐藤樹,菅原槙人, 責任著者, 日本AEM学会
日本AEM学会誌, 2023年04月, [査読有り] - 小児用補助人工心臓用5軸制御セルフベアリングモータの駆動系簡素化の検討
長真啓,増澤徹,北山文矢,西中知博,巽英介, 日本AEM学会
日本AEM学会誌, 2023年02月, [査読有り] - 〔主要な業績〕Radial Passive Stability Analysis of Magnetically Levitated Impeller Position for the Development of Flow Rate Estimations of a Ventricular Assist Device
Shuya Shida; Toru Masuzawa; Masahiro Osa, 責任著者, 生体医工学会
Advanced Biomedical Engineering, 2022年11月, [査読有り] - 〔主要な業績〕小児用補助人工心臓用磁気浮上モータの異なる制御軸数における磁気支持性能と電力特性の評価
山下 俊大; 増澤 徹; 長 真啓; 巽 英介; 西中 知博, 責任著者, 掲載決定, 日本AEM学会
日本AEM学会誌, 2022年08月, [査読有り] - Dynamic motion analysis of impeller for the development of real-time flow rate estimations of a ventricular assist device
Shuya Shida; Toru Masuzawa; Masahiro Osa, 責任著者, European Society for Artificial Organs
The International Journal of Artificial Organs, 2022年01月, [査読有り] - 〔主要な業績〕Double Stator Axial Gap Type Ultra-Compact 5-DOF Controlled Self-Bearing Motor for Rotary Pediatric Ventricular Assist Device
Masahiro Osa; Toru Masuzawa; Kiyoshi Yamaguchi; Eisuke Tatsumi, 責任著者, Accepted, IEEE
IEEE Transactions on Industry Applications, 2021年08月, [査読有り] - 補助人工心臓装着を支援する自己接合型脱血管の研究開発
吉田尚記・増澤徹・長真啓・尾関和秀・岸田晶夫・築谷朋典・水野敏秀・西中知博・巽英介, 責任著者, ライフサポート学会
ライフサポート, 2021年07月, [査読有り] - Effects of gravity on flow rate estimations of a centrifugal blood pump using the eccentric position of a levitated impeller
Shuya Shida; Toru Masuzawa; Masahiro Osa, 責任著者, European Society for Artificial Organs
The International Journal of Artificial Organs, 2020年05月, [査読有り] - 冠動脈バイパス手術における血管接合支援デバイスの研究開発
羽根田洋輔,増澤徹,長真啓,尾関和秀,岸田晶夫,巽英介, 責任著者, ライフサポート学会
ライフサポート, 2019年10月, [査読有り] - Characterizing A Compact 5-DOF controlled Self-Bearing Motor with Modified Magnetic Circuit to Improve Suspension Performance for Pediatric VAD
Masahiro OSA; Toru MASUZAWA; Ryoga ORIHARA; Eisuke TATSUMI, 責任著者, 日本AEM学会
Journal of JSAEM, 2019年07月, [査読有り] - 全置換型磁気浮上連続流人工心臓の流量バランス制御のための数値流体解析を用いた右心用ポンプの改良
牧田丈靖,増澤徹,信太宗也,長真啓,Daniel L Timms, 責任著者, ライフサポート学会
ライフサポート, 2019年06月, [査読有り] - Performance enhancement of a magnetic system in a ultra compact 5-DOF-Controlled self-bearing motor for a rotary pediatric ventricular assist device to diminish energy input
Masahiro Osa; Toru Masuzawa; Ryoga Orihara; Eisuke Tatsumi, 責任著者, MDPI
Actuators, 2019年04月, [査読有り] - Flow rate estimation of a centrifugal blood pump using the passively stabilized eccentric position of a magnetically levitated impeller
Shuya Shida; Toru Masuzawa; Masahiro Osa, 責任著者
The International Journal of Artificial Organs, 2019年02月, [査読有り] - Magnetic suspension performance enhancement of ultra-compact 5-DOF controlled self-bearing motor for rotary pediatric ventricular assist device
Masahiro Osa; Toru Masuzawa; Ryoga Orihara; Eisuke Tatsumi, 責任著者, ISMB
Proc. of the 16th ISMB, 2018年08月 - 人工心臓への適用を目的とした4軸制御型磁気軸受の開発
小泉綾香,増澤徹,長真啓, 責任著者
日本AEM学会誌, 2018年06月, [査読有り] - 心拍同期型磁気浮上体外循環血液ポンプの径方向安定性評価
佐藤遼太,増澤徹,長真啓,大野康平,西村隆,許俊鋭, 責任著者
日本AEM学会誌, 2018年06月, [査読有り] - 全置換型磁気浮上人工心臓への反発型永久磁石磁気軸受の組み込み
牧田丈靖,増澤徹,國府田芳彰,長真啓,Daniel L TIMMS, 責任著者, 日本AEM学会
日本AEM学会誌, 2018年06月, [査読有り] - ダブルステータ型アキシャルギャップ磁気浮上モータの5軸制御方式を活用した小児用人工心臓循環補助時の外乱力推定と磁気浮上特性評価
長真啓、増澤徹、斎藤拓也、巽英介, 責任著者, 日本AEM学会
日本AEM学会誌, 2018年03月, [査読有り] - 薄小型補助人工心臓用セルフベアリングモータの改良
村上倫子、増澤徹、小沼弘幸、西村隆、許俊鋭, 責任著者, 日本AEM学会
日本AEM学会誌, 2018年03月, [査読有り] - Analysis of the effect of the size of three-dimensional micro-geometric structures on physical adhesion phenomena using microprint technique
Akiko Oota-Ishigaki; Toru Masuzawa; Kazuaki Nagayama, 責任著者
The International Journal of Artificial Organs, 2018年, [査読有り] - Effects of eccentric impeller position on radial passive stability in a magnetically levitated centrifugal blood pump with a double volute
Shuya Shida; Toru Masuzawa; Masahiro Osa; Ryota Sato, Evaluation of the impeller radial stability is important from the bioengineering point of view in the development of mechanical circulatory support devices (MCSDs) for safer use as bridge for several months or destination therapy for years. In this study, radial stability of a magnetically levitated impeller in a centrifugal blood pump with an axially magnetic suspension system was evaluated by investigating the effects of the eccentric impeller position on passive stability, aiming to propose a pump design guide for the development and safer clinical use of MCSDs. First, impeller displacements in the prototype pump were measured using a mock loop together with laser displacement sensors. Then, the radial hydraulic forces exerted on an eccentric impeller were calculated using computational fluid dynamics (CFD) analysis for four volute-casing geometries. In addition, hemocompatibility was assessed using CFD calculations of scalar shear stress exerted on blood. Measurement of impeller displacement showed that the displacement varied from 0.56 to 0.27 mm at a rotational speed of 1800 rpm as the flow rate increased from 0 to 6.5 L/min. In the CFD calculation, the radial hydraulic force increased linearly from 0.2 to 1.7 N as the impeller displacement increased from 0 to 0.5 mm for all the double volute geometries, under conditions of a rotational speed of 1800 rpm and flow rates of 3, 5 and 7 L/ min. These results indicate that the impeller stability in the prototype pump is acceptable at the operation conditions of ventricular assist devices, because the magnetic bearing stiffness of radial component was 4.1 N/mm. In the pressure recovery analysis of eccentric impellers, a double volute was not effective because of the unbalanced pressure field generated by the unbalanced pressure recovery. Thus, the increase in radial hydraulic force associated with an eccentric impeller could not be avoided by changing the conventional double volute design. The CFD analysis of geometrical variation indicated that widening of the radial clearance is an effective approach to improve the radial stability as well as hemocompatibility, although the radial clearance should be designed based on trade-offs among impeller stability, hemocompatibility and pump performance., Japanese Society for Medical and Biological Engineering
Advanced Biomedical Engineering, 2018年, [査読有り] - Magnetic Levitation Performance of Miniaturized Magnetically Levitated Motor with 5-DOF Active Control
Masahiro OSA; Toru MASUZAWA; Takuya SAITO; Eisuke TATSUMI, 責任著者,Mechanical circulatory support (MCS) therapy plays a significant role in an alternative therapy of heart transplants for pediatric heart disease patients. However, continuous flow rotary MCS devices for pediatric patients are still undergoing development, and have not been clinically available technology. Technical difficulties, such as high durability, better blood compatibility and miniature device size, prevent the pediatric MCS devices development. In this study, a double stator axial gap maglev motor for pediatric MCS device has been developed. The maglev motor has two identical motor stators, and a levitated rotor impeller which is aligned between the stators. The levitated rotor impeller is fully suspended with 5-degrees of freedom (5-DOF) active control. A double stator mechanism enhances motor torque production. A miniaturized maglev motor was designed and developed based on FEM magnetic field analysis for use in implantable ventricular assist devices (VADs). The diameter and height of the developed maglev motor are 22 mm and 33 mm. This paper is an initial report on the magnetic levitation and rotation performance of the miniaturized maglev motor. The levitated rotor impeller was magnetically levitated and rotated with the 5-DOF active control. The oscillation amplitudes (x, y and z) and inclination angles (θx and θy) of the levitated rotor impeller were then evaluated in both air and water. The developed maglev motor achieved non-contact rotation up to 1600 rpm in air and 4500 rpm in water, respectively. The oscillation amplitudes and inclination angles were sufficiently suppressed in water due to fluid damping. After these experiments, a magnetic circuit of the maglev motor was modified in order to achieve further stable levitation. The developed maglev motor then indicated potential to achieve the practical use of maglev rotatory pediatric VAD.
, 一般社団法人 日本機械学会
15th International Symposium on Magnetic Bearings, 2017年10月, [査読有り] - Magnetic levitation performance of miniaturized magnetically levitated motor with 5-DOF active control
Masahiro Osa; Toru Masuzawa; Takuya Saito; Eisuke Tatsumi, 責任著者,Mechanical circulatory support (MCS) therapy plays a significant role in an alternative therapy of heart transplants for pediatric heart disease patients. However, continuous flow rotary MCS devices for pediatric patients are still undergoing development, and have not been clinically available technology. Technical difficulties, such as high durability, better blood compatibility and miniature device size, prevent the pediatric MCS devices development. In this study, a double stator axial gap maglev motor for pediatric MCS device has been developed. The maglev motor has two identical motor stators, and a levitated rotor impeller which is aligned between the stators. The levitated rotor impeller is fully suspended with 5-degrees of freedom (5-DOF) active control. A double stator mechanism enhances motor torque production. A miniaturized maglev motor was designed and developed based on FEM magnetic field analysis for use in implantable ventricular assist devices (VADs). The diameter and height of the developed maglev motor are 22 mm and 33 mm. This paper is an initial report on the magnetic levitation and rotation performance of the miniaturized maglev motor. The levitated rotor impeller was magnetically levitated and rotated with the 5-DOF active control. The oscillation amplitudes (x, y and z) and inclination angles (θx and θy) of the levitated rotor impeller were then evaluated in both air and water. The developed maglev motor achieved non-contact rotation up to 1600 rpm in air and 4500 rpm in water, respectively. The oscillation amplitudes and inclination angles were sufficiently suppressed in water due to fluid damping. After these experiments, a magnetic circuit of the maglev motor was modified in order to achieve further stable levitation. The developed maglev motor then indicated potential to achieve the practical use of maglev rotatory pediatric VAD.
, JSME
Mechanical Engineering Journal, 2017年10月, [査読有り] - Development of a small magnetic levitated centrifugal blood pump using a radial type self-bearing motor and axial position change of rotor-impeller by rotational magnetic field
Hiroyuki Onuma; Toru Masuzawa; Michiko Murakami, ラスト(シニア)オーサー,A small magnetic levitated centrifugal blood pump using a radial type self-bearing motor has been developed for use as an implantable artificial heart. In order to realize an implantable blood pump for a small adult patient, miniaturization and high efficiency of the device are necessary. In this study, a radial type self-bearing motor which is small-diameter and thin was developed, and the axial position change of the rotor-impeller by the rotational magnetic field was proposed. Magnetic suspension characteristics and motor performance were compared the center axial position of the rotor with the displaced axial position of the rotor. Additionally, a magnetic levitated centrifugal blood pump using the self-bearing motor was developed, and pump performance and levitation performance were measured. The magnetic suspension performance in the radial direction was enough ability to control the radial position of the rotor. The magnetic suspension force in the radial direction decreased by displacing the axial position of the rotor. The passive stability performance in the axial direction was enough ability to suspend the rotor. The restoring force was possible to be varied by the rotation magnetic field. The motor performance decreased by shifting the phase angle of the rotational magnetic field from 90 degrees and displacing the axial position of the rotor. At the operating condition with a flow rate of 5 L/min against a pressure of 100 mm Hg, the oscillation amplitude in x, y, z direction were 0.014 mm, 0.014 mm and 0.039 mm, respectively. And, the total power consumption was 7.1 W. The developed magnetic levitated centrifugal blood pump has demonstrated sufficient levitation performance and low total power consumption. The average displacement in z direction of the rotor-impeller was possible to change by changing the phase angle of the rotational magnetic field. By decreasing the phase angle from 90 degrees in range of from 60 degrees to 90 degrees, it is possible to improve the levitation performance with just a little increases the total power consumption.
, JSME
Mechanical Engineering Journal, 2017年10月, [査読有り] - Compact Maglev Motor with Full DOF Active Control for Miniaturized Rotary Blood Pumps
Masahiro Osa; Toru Masuzawa; Ryoga Orihara; Eisuke Tatsumi, LDIA2017
Proc. of LDIA2017, 2017年09月 - 作動流体粘度が磁気浮上補助人工心臓のポンプ特性およびインペラ浮上性能に与える影響
村上倫子,増澤徹,小沼弘幸,西村隆,許俊鋭, 責任著者, ライフサポート学会
ライフサポート学会誌, 2017年08月, [査読有り] - 超小型磁気浮上式小児用人工心臓の開発
斎藤拓也,増澤徹,長真啓,巽英介, 責任著者,A 5-degrees of freedom (5-DOF) controlled maglev motor and a centrifugal blood pump have been developed for pediatric ventricular assist devices (VADs). The magnetically suspended pediatric VAD consists of a top stator, a bottom stator and a levitated impeller. A double stator mechanism enhances a torque production. The maglev pediatric VAD has an outer diameter of 22 mm, a total length of 34 mm and a total volume of 18 cc. In this study the pump performance of the developed centrifugal pump was investigated, as well as the magnetic suspension ability of the developed 5-DOF controlled self-bearing motor was evaluated. The developed maglev pediatric VAD produced a flow rate up to 2.5 L/min against a pump head pressure of 100 mmHg at an impeller rotating speed of 5000 rpm. The maximum oscillation amplitudes that were 0.08 mm in axial direction and 0.19 mm in radial direction were less than the clearance of the centrifugal blood pump.
, 日本AEM学会
日本AEM学会誌, 2017年07月, [査読有り] - 全置換型磁気浮上人工心臓のための反発型磁気軸受の検討
國府田芳彰,増澤徹,長真啓,Dniel L Timms, 責任著者,We have developed a magnetically levitated total artificial heart. The stator of the device has a magnetic bearing and a motor stator set at center of the device. The left and right impellers are connected by a shaft through the center hall of the stator core. The axial position and tilting of the levitated impeller are controlled by the magnetic bearing. The radial displacement of the impeller is supported with a passive stability. We propose the application of a repulsive passive permanent magnetic bearing, PMB, for improvement of the radial stiffness of the device. A magnetic field analysis with finite element method was performed to investigate a suitable PMB. As a result, the PMB which has two radially magnetized outer permanent magnets and an axial magnetized inner permanent magnet has better performance and the radial stiffness increased up to 2.5 times of passive stability's one.
, 日本AEM学会
日本AEM学会誌, 2017年07月, [査読有り] - Effect of flow around three-dimensional micro-geometric structures on adhesion phenomena
Akiko Oota-Ishigaki; Toru Masuzawa; Takayuki Shibata, 責任著者, ライフサポート学会
ライフサポート学会誌, 2017年06月, [査読有り] - Magnetically suspended motor system applied to artificial hearts and blood pumps
Toru Masuzawa, Magnetic levitation technology, for magnetic bearings and magnetically suspended motors, is a cutting edge technology to produce artificial hearts and higher performance blood pumps. A wider blood gap and the elimination of the contacting parts in the device based on the maglev technology provide better blood compatibility and higher durability of the device. Several maglev pumps developed at Ibaraki University are introduced in this article. Maglev pumps have been designed for different medical requirements and for different magnetic suspension systems. All pumps have sufficient suspension and pump performance as blood pumps. The axial suspension system with a double biased hybrid magnetic bearing is explained in detail as one example of maglev blood pumps., SAGE PUBLICATIONS LTD
PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART I-JOURNAL OF SYSTEMS AND CONTROL ENGINEERING, 2017年05月, [査読有り] - 心拍同期型磁気浮上血液ポンプにおける受動安定軸の浮上安定性評価
下堀拓己,増澤徹,西村隆,許俊鋭, 責任著者, 日本AEM学会
日本AEM学会誌, 2016年09月, [査読有り] - ラジアル型セルフベアリングモータにおける受動安定性の簡易推定式の検討
小沼弘幸,増澤徹,村上倫子, 責任著者
日本AEM学会誌, 2016年09月, [査読有り] - Development of radial type self-bearing motor for small centrifugal blood pump
Hiroyuki ONUMA; Toru MASUZAWA; Michiko MURAKAMI, 責任著者
15th International Symposium on Magnetic Bearings, 2016年08月, [査読有り] - Thermal denaturation behavior of collagen fibrils in wet and dry environment
Yosuke Suwa; Kwangwoo Nam; Kazuhide Ozeki; Tsuyoshi Kimura; Akio Kishida; Toru Masuzawa, We have developed a new minimally invasive technique--integrated low-level energy adhesion technique (ILEAT)--which uses heat, pressure, and low-frequency vibrations for binding living tissues. Because the adhesion mechanism of the living tissues is not fully understood, we investigated the effect of thermal energy on the collagen structure in living tissues using ILEAT. To study the effect of thermal energy and heating time on the structure of the collagen fibril, samples were divided in two categories-wet and dry. Further, atomic force microscopy was used to analyze the collagen fibril structure before and after heating. Results showed that collagen fibrils in water denatured after 1 minute at temperatures higher than 80 degrees C, while partial denaturation was observed at temperatures of 80 degrees C and a heating time of 1 min. Furthermore, complete denaturation was achieved after 90 min, suggesting that the denaturation rate is temperature and time dependent. Moreover, the collagen fibrils in dry condition maintained their native structure even after being heated to 120 degrees C for 90 min in the absence of water, which specifically suppressed denaturation. However, partial denaturation of collagen fibrils could not be prevented, because this determines the adhesion between the collagen molecules, and stabilizes tissue bonding. (c) 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 104B: 538-545, 2016., WILEY-BLACKWELL
JOURNAL OF BIOMEDICAL MATERIALS RESEARCH PART B-APPLIED BIOMATERIALS, 2016年04月, [査読有り] - Miniaturizing 5-DOF fully controlled axial gap maglev motor for pediatric ventricular assist devices
Masahiro Osa; Toru Masuzawa; Takuya Saito; Eisuke Tatsumi, An axial gap maglev motor with double stators that can control five-degrees of freedom (5-DOF) of rotor postures has been newly developed for pediatric ventricular assist devices (VADs). The motor has two stators that have an identical structure and a levitated rotor. The rotor is levitated magnetically between the stators and is driven by the mechanism of a synchronous permanent magnet motor. A double-stator structure achieves active 5-DOF posture control and enhances torque production. In this paper, a maglev motor as an actuator of pediatric VAD has been designed and miniaturized based on magnetic field FEM analysis. The performance of the maglev motor, the static magnetic suspension force and the torque of the developed motor, is measured experimentally and is sufficient for stable levitation and rotation., IOS PRESS
INTERNATIONAL JOURNAL OF APPLIED ELECTROMAGNETICS AND MECHANICS, 2016年, [査読有り] - A double sided stator type axial self-bearing motor development for left ventricular assist devices
Nobuyuki Kurita; Takeo Ishikawa; Naoki Saito; Toru Masuzawa, A self-bearing motor that has tilt control function is proposed. The rotor has two permanent magnets on each side (four PMs in total). The two stators have eight poles each with concentrated windings. The operating principle was clarified by theoretical analysis and FEM analysis. Moreover, it was shown that the proposed motor can control the translation motion, inclinational and rotational motion independently. An experimental setup was fabricated and magnetically levitated rotation was achieved. The control performance of the self-bearing motor was also investigated. In addition, the proposed axial self-bearing motor is also designed and fabricated into a prototype maglev pump. Fabricated pump test rig showed sufficient performance for left ventricular assist device (LVAD) application of 4.35 L/min at 100 mm Hg., IOS PRESS
INTERNATIONAL JOURNAL OF APPLIED ELECTROMAGNETICS AND MECHANICS, 2016年, [査読有り] - Radial position active control of double stator axial gap self-bearing motor for pediatric VAD
Masahiro Osa; Toru Masuzawa; Naoki Omori; Eisuke Tatsumi, 責任著者
Mechanical Engineering Journal, 2015年08月, [査読有り] - IPM型5軸制御セルフベアリングモータの小型化とコギングトルク特性改善に関する研究
松田健一; 熊谷渉; 近藤良; 増澤徹, ラスト(シニア)オーサー, 5-DOF self-bearing motor possesses the functions of a motor, two radial active magnetic bearings (AMBs), and an axial AMB. It is possible to downsize the AMB system while still maintaining a high level of support performance. In a 5-DOF self-bearing motor, the IPM rotor generates bias fluxes in not only the radial direction but also in the axial and tilt directions without any side surface permanent magnets. However, cogging torques are inherently generates by the magnetic flux flow in a IPM rotor. The proposed flux recovery-type permanent magnets configuration was analyzed using the 3-dimensional finite element method. The results show a significant reduction of the cogging torques and an improvement to motor efficiency., The Japan Society of Mechanical Engineers
日本機械学会論文集, 2015年06月, [査読有り] - 磁気浮上型心臓治療用血液ポンプへのセンサレスモータ制御の適用
大森直樹; 増澤徹; 長真啓; 下堀拓己; 西村隆; 許俊鋭, 責任著者
日本AEM学会誌, 2015年06月, [査読有り] - 薄小型磁気浮上補助人工心臓における浮上インペラの受動安定軸の変動計測
吉田翔一; 増澤徹; 村上倫子; 小沼弘幸; 西村隆; 許俊鋭, 責任著者
日本AEM学会誌, 2015年06月, [査読有り] - Size-reduced two-dimensional integrated magnetic sensor fabricated in 0.18μm CMOS process
Takayuki Kimura; Kazuya Uno; Toru Masuzawa, ラスト(シニア)オーサー, Two-dimensional integrated magnetic sensors have been investigated in order to reduce their size for use in a magnetic self-levitation motor. The two-dimensional integrated magnetic sensor investigated in this paper is composed of a 16 x 16 array of Hall sensors and fabricated by a 0.18-m complementary metal-oxide-semiconductor (CMOS) standard process. The sizes of the Hall elements are 1 x 1, 2 x 2, 3 x 3, and 6 x 6 m(2). Hall element of dimension 1 x 1 m(2)was the minimum size in the fabrication process rule. The dimension of one pixel in which the Hall element was embedded was 20 x 20 m(2). The average sensitivity of the arrayed Hall sensors at four sizes was about 0.140 mV/mT with a DC magnetic field. The product sensitivity at four sizes of Hall sensors was about 0.089 mV/(mAmT), which is better than that of our previous work. Degradation of the product sensitivity was not seen in reduced-size Hall elements. These results reveal that a Hall element of size 1 x 1 m(2) has enough sensitivity for sensing the impeller position of a magnetically suspended motor. (c) 2015 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc., WILEY-BLACKWELL
IEEJ Trans, 2015年05月, [査読有り] - 全置換型磁気浮上人工心臓と流量バランス制御
山田悠,増澤徹,Daniel L TImms, 責任著者, An innovative Bi-Ventricular Artificial Heart (IB-Heart) has been successfully developed with a single magnetically suspended motor. The device has auto flow regulation function which reacts to atrial pressure change in order to balance the flow rate of left and right pump. The zero power control is adopted to control axial position of levitated impeller in the IB-Heart. The rate of change of the axial position of the impeller on the atrial pressure change is the key factor of this devices flow regulation function since the flow rate of the pumps is regulated with axial position changing of the levitated impeller. The flow regulating ability of the IB-Heart and the relationship between the rod cross-sectional area and the flow regulation function was investigated. The maglev motor was redesigned with 3-D magnetic field analysis to improve the flow regulation function., The Japan Society of Applied Electromagnetics and Mechanics
日本AEM学会誌, 2015年03月, [査読有り] - 小児用補助人工心臓のための小型磁気浮上モータの第一試作
大森直樹,増澤徹,長真啓,巽英介, 責任著者, A miniaturized magnetically levitated motor which can actively control 5-degrees of freedom (5-DOF) of impeller postures has been newly developed for a paediatric ventricular assist device (VAD). Developed motor consists of a top stator, a bottom stator and a levitated impeller that is set between the both stators. The diameter and the height of the motor are 28 mm and 41 mm, respectively. Magnetic field analysis with finite element method was performed in order to design the geometry of motor permanent magnets and a stator. Corners of the motor permanent magnets were cut to produce sinusoidal distribution of magnetic flux density and to reduce the cogging torque. The developed maglev motor produces sufficient suspension force and rotates the levitated impeller up to a rotating speed of 6000 rpm with sufficient posture control performance., The Japan Society of Applied Electromagnetics and Mechanics
日本AEM学会誌, 2015年03月, [査読有り] - 磁気ビーズを用いた磁気励振細胞刺激システム
増澤 徹,服部圭介,林照剛,木村剛,岸田晶夫, 筆頭著者, We have been investigating the mechanical cell stimulation because it has the possibility to enhance cell function without any chemical and biological material. In this paper, a newly developed cell stimulation system using magnetic beads attached on the cell wall is presented. The magnetic beads are attached on cultured cells in advance and an alternating magnetic field produced by the electric magnet is exposed onto the cells attached the magnetic beads. The beads are vibrated with the magnetic field and the cell wall received the vibration stimulation. Basic performance of the stimulation system is evaluated in this paper. The system can produce an attractive force of 30 pN onto the beads and can vibrate the beads up to a vibration frequency of 80 Hz with an oscillation amplitude of 450 nanometers. The vibration of the magnetic beads on the cultured cells with a vibration frequency of 10 Hz was observed successfully with human mesenchymal stem cells., The Japan Society of Applied Electromagnetics and Mechanics
日本AEM学会誌, 2015年03月, [査読有り] - 回転数周期的変動時の磁気浮上型血液ポンプの浮上安定性と溶血性能の検討
増澤徹; 山口聡史; 下堀拓己; 西村隆; 許俊鋭, 筆頭著者, A novel blood pump with magnetically levitated impeller has been developed to recover cardiac function of acute heart failure patients. The pump assists patients heart and the impellers rotational speed are changed based on synchronizing with heart beat in order to increase coronary flow of patients heart. Impeller levitation stability of the pump operated in pulsatile mode was evaluated with a mock circuit filled with water. In the pulsatile mode, the rotational speed was changed from 800 rpm to 1800 rpm with a beat rate of 60 bpm. Maximum axial displacement of the impeller is 22 % of the blood gap between the impeller and casing. Characteristics of hemolysis of the pump were examined within in-vitro hemolysis tests. NIH value of the maglev pump is about half time of it of a commercial based extracorporeal pump in constant speed operation. Even NIH value operated in the pulsatile mode is about two times of the commercial based pumps one and it is acceptable range for clinical usage. The developed maglev pump indicates sufficient impeller levitation stability and hemolysis property., The Japan Society of Applied Electromagnetics and Mechanics
日本AEM学会誌, 2015年03月, [査読有り] - Effect of incorporation of deuterium on vacancy-type defects of a-C:H films prepared by plasma CVD
K.Ozeki; D.Sekida; A.Uedono; K.K.Hirakuri; T.Masuzawa, ラスト(シニア)オーサー
Applied Surface Science, 2015年01月, [査読有り] - Pediatric VAD with Five Degrees of Freedom Control MAGLEV Motor
T. Masuzawa; M. Osa; N. Omori; E. Tatsumi
41st Annual European Society for Artificial Organs (ESAO) Congress, 2014年09月, [招待有り] - The relationship between the thrombogenicity and the generated flow around 3-dimensional micro geometrical structures on the bio-material -Investigation of micro flow-
Ota-Ishigaki A; Masuzawa T; Shibata T; Kawashima T; Maruyama O
The 10th International Student Conference at Ibaraki University, 2014年09月 - Cadiovascular circulation simulator to evaluate ventricular assist effect
Kurosaki W; Masuzawa T
The 10th International Student Conference at Ibaraki University, 2014年09月 - アウターロータ型5軸制御セルフベアリングモータに関する研究
松田健一、平根龍也、近藤良、増澤徹
日本AEM学会誌, 2014年09月, [査読有り] - Cascade pump for mechanical circulatory support
Toru Masuzawa; Michiko Murakami, Cascade pump has a rotating disk with circumferential vanes. Flow channel is constructed around the circumferential space of the rotating disk. The cascade pump has thin structure because the inlet and outlet ports are set on the same plane with the rotating disk. The gap between disk surface and casing should be less than 0.05 mm to prevent pressure loss through the gap in the cascade pump. The gap of the cascade pump produces higher hemolysis and thrombus in it. The disk surface gap is minimized with modifying the impeller to ring shape with a radial self-bearing motor to achieve better blood compatibility. Developed pump has maximum diameter of 59 mm and a thickness of 22 mm. Maximum flow rate and head pressure are 7 L/min and 330 mmHg, respectively. The hemolysis property is just two times of the commercial based blood pump and sufficient for mechanical circulatory support., Japan Soc. of Med. Electronics and Biol. Engineering
Transactions of Japanese Society for Medical and Biological Engineering, 2014年08月, [査読有り] - Total artificial heart with a single maglev motor
Toru Masuzawa; Daniel L. Timms, A total artificial heart which has a single maglev motor with double centrifugal pumps has been developed. The maglev motor is set between a left pump and a right pump. The impellers of the left and right pumps are connected with a connecting rod passed through at the center of the motor. The impellers are levitated magnetically and rotated with identical rotating speed. The flow balance between the left and right pumps is achieved by shifting the levitated impeller in the axial direction. Zero power control is adopted for preload sensitive control. The maximum diameter and height of the pump are 76 mm and 61 mm, respectively. The pump indicates sufficient pump performance with the maximum flow rate of 20 L/min in usage condition. The flow rate is changed more than by 10 % of the flow rate of the pumps with an impeller position changing of 0.4 mm., Japan Soc. of Med. Electronics and Biol. Engineering
Transactions of Japanese Society for Medical and Biological Engineering, 2014年08月, [査読有り] - Magnetically suspended motor system for artificial hearts and blood pumps
Masuzawa T
14th International Symposium on Magnetic Bearings, 2014年08月, [査読有り] - Optimization design of magnetically suspended system for the BiVACOR total artificial heart
Kurita N; Timm D; Greatrex N; Kleinheyer M; Masuzawa T
14th International Symposium on Magnetic Bearings, 2014年08月, [査読有り] - Radial Position Active Control of Double Stator Axial Gap Self-bearing Motor for Paediatric VAD
Osa M; Masuzawa T; Omori N; Tatsumi E
14th International Symposium on Magnetic Bearings, 2014年08月, [査読有り] - Thin Maglev Ventricular Assist Device with radial Type Self-bearing Motor
Murakamia M; Masuzawa T; Yoshida S; Onuma H; Nishimura T; Kyo S
14th International Symposium on Magnetic Bearings, 2014年08月, [査読有り] - Evaluation of Magnetic Suspension Characteristics and Levitation Performance of A Centrifugal Blood Pump Using Radial Type Self-Bearing Motor
Onuma H; Masuzawa T
14th International Symposium on Magnetic Bearings, 2014年08月, [査読有り] - Magnetically suspended artificial heart
Masuzawa T
8th Asia-Pacific Symposium on Applied Electromagnetics and Mechanics 2014, 2014年07月, [招待有り] - 12突極ラジアル型セルフベアリングモータの磁気支持特性の推定
小沼弘幸,増澤徹
日本AEM学会誌, 2014年06月, [査読有り] - Pulsatile operation of the BiVACOR TAH - Motor design, control and hemodynamics
Matthias Kleinheyer; Daniel L. Timms; Nicholas A. Greatrex; Toru Masuzawa; O. Howard Frazier; William E. Cohn, Although there is limited consensus about the strict requirement to deliver pulsatile perfusion to the human circulatory system, speed modulation of rotary blood pumps is an approach that may capture the benefits of both positive displacement and continuous flow blood pumps. In the current stage of development of the BiVACOR Total Artificial Heart emphasis is placed on providing pulsatile outflow from the pump. Multiple pulsatile speed profiles have been applied in preliminary in-vivo operation in order to assess the capability of the TAH to recreate a physiologic pulse. This paper provides an overview about recent research towards pulsatile BiVACOR operation with special emphasis on motor and control requirements and developments., IEEE
2014 36TH ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY (EMBC), 2014年, [査読有り] - シングル磁気浮上モータ方式全人工心臓の開発
西村宣彦、増澤徹、ダニエルLティムス, A magnetically suspended total artificial heart has been developed with a single magnetically suspended motor. The device has double pumps to replace the function of the left and right ventricles. A stator which has both of a magnetic bearing core and a motor stator core is set at center of the device. The left and right pump impellers are connected with a rod through the center hall of the stator core. Attractive forces produced by the magnetic bearing and the motor are made balance to suspend the rotating impellers. Flow difference between the left and the right pump is regulated by changing the amount of the secondary flow through blood gap between impeller top edge and pump casing by shifting the impeller position axially. Flow rate of the left pump is changed 4.1∼6.7 L/min, flow rate of the right pump is changed 6.5∼7.4 L/min when axial position of the impeller is shifted by ±0.2 mm., The Japan Society of Applied Electromagnetics and Mechanics
日本AEM学会誌, 2013年06月 - Influence of the source gas ratio on the hydrogen and deuterium content of a-C:H and a-C:D films: Plasma-enhanced CVD with CH4/H-2, CH4/D-2, CD4/H-2 and CD4/D-2
K. Ozeki; D. Sekiba; T. Suzuki; K. Kanda; M. Niibe; K. K. Hirakuri; T. Masuzawa, Amorphous hydrogenated carbon (a-C:H) and amorphous deuterated carbon (a-C:D) films were prepared using plasma-enhanced chemical vapor deposition (PECVD) from CD4, H-2, CD4 and D-2 source gases. Fourteen different samples were prepared by changing the source gas ratios of CH4/H-2, CH4/D-2, CD4/H-2, and CD4/D-2. The concentrations of hydrogen (H) and deuterium (D) relative to carbon (C) in the films were determined by elastic recoil detection analysis (ERDA) and Rutherford backscattering spectroscopy (RBS). The sp(2)/(sp(2) + sp(3)) ratios of the films were analyzed by near-edge X-ray absorption fine structure (NEXAFS) measurements. Hardness and mass density of the films were measured using a nanoindenter and X-ray reflectivity (XRR), respectively. For all combinations of source gas, the H and D concentrations varied by only 4.0 at.%. For the CH4/D-2 source gas, the D concentration in the film increased from 0 at.% with the D-2/(CH4 + D-2) source gas combination to 11.2 at.% for the 80% D-2/(CH4 + D-2) source gas combination. The increase in D concentration exceeded the increase in total H and D concentration (3.4 at.%). For CH4/D-2 source gas, the H concentration decreased as the D concentration increased. For the CD4/H-2 source gas, we observed the opposite tendency. Additionally, an isotope effect between the a-C:H films and the a-C:D films was observed, with preferential incorporation of H over D. From the NEXAFS measurements, the sp(2)/(sp(2) + sp(3)) ratios in all of the samples were between 38.8% and 40.8%. A correlation between the sp(2)/(sp(2) + sp(3)) ratio and the H-2 or D-2 gas source ratio was not observed. The hardness and density of the films decreased when the H-2 or D-2 source gas ratio increased. Even though the H concentration in the a-C:H films was higher than the D concentration in the a-C:D films, the a-C:D films had lower hardness and mass density values. These findings suggest that information concerning the voids, nanostructures, sp(2)/sp(3) ratios and H concentrations of hydrogenated amorphous carbon films is crucial for evaluation of their mechanical properties. (C) 2012 Elsevier B.V. All rights reserved., ELSEVIER SCIENCE BV
APPLIED SURFACE SCIENCE, 2013年01月, [査読有り] - Phase Composition of Sputtered Film from a Mixture Target of Hydroxyapatite and Strontium-apatite
Ozeki K; Hoshino T.; Aoki H; Masuzawa T, To obtain an Sr-substituted hydroxyapatite thin film, sputter-coating was performed on a cellulose filter acting as a substrate from the mixture target of hydroxyapatite (HA) and strontium-apatite (SrAp) at an Ar pressure of 0.5-5.0 Pa. The ratio of the SrAp in the mixture target was varied from 25% to 100%. After coating, the films were heated at 700 degrees C to remove the cellulose filter substrate, and the crystalline phases were identified by X-ray diffraction (XRD). The sputter-coated film was identified as the Sr-substituted beta-tri-calcium phosphate (TCP) and the Sr-substituted beta-calcium pyrophosphate (CPP) as well as the Sr-substituted HA. The weight ratio of the Sr-substituted HA decreased with increasing Ar pressure or with an increasing ratio of SrAp to HA in the target. The average Sr/(Ca + Sr) molar ratio in the film was 1.9%-3.5% slightly lower than the initial SrAp ratio of the target, and the ratio was not influenced by the Ar pressure. In the (Sr + Ca)/P ratio, the ratio decreased while increasing the SrAp ratio in the target., JOURNAL MATER SCI TECHNOL
Journal of Materials Science and Technology, 2013年, [査読有り] - Antithrombogenicity of Amorphous Deuterated Carbon Film Prepared by RF-plasma CVD
K. Ozeki; D. Sekiba; K.K. Hirakuri; T. Masuzawa
Nano Biomedicine, 2013年, [査読有り] - The adsorptive behavior of albumin and lysozyme proteins on rod-shaped and plate-shaped hydroxyapatite
K. Ozeki; T. Hoshino; H. Aoki and T. Masuzawa, The adsorption behavior of albumin (BSA) and lysozyme (LSZ) on rod-shaped and plate-shaped hydroxyapatite (HA) was investigated to evaluate the influence of crystal orientation and morphology on the selective protein adsorption of HA. The rod-shaped HA was prepared by hydrothermal treatment from beta-tricalcium phosphate (beta-TCP) in H3PO4 solution (pH 2.0 and 4.0 for HA-pH 2.0 and HA-pH 4.0). The plate-shaped HA was synthesized by hydrolysis of CaHPO4-2H(2)O (DCPD) in NaOH solution at 40 degrees C and 80 degrees C (HA-40 degrees C and HA-80 degrees C). The synthesized HA was characterized using scanning electron microscopy (SEM) and X-ray diffractometry (XRD). HA-pH 2.0 and HA-pH 4.0 produced rod-shaped crystals that were highly oriented to the a-face plane, whereas HA-40 degrees C and HA-80 degrees C showed a plate-like shape and a c-face preferred orientation. The peak intensity ratio I(300)/I(002) (a/c intensity ratio) from the XRD patterns increased in the following order: HA-80 degrees C, HA-40 degrees C, HA-pH 2.0 and HA-pH 4.0. It also increased as the Ca/P ratio decreased. The amount of adsorbed BSA increased in the following order: HA-pH 4.0, HA-pH 2.0, HA-40 degrees C and HA-80 degrees C. The amount of adsorbed LSZ on HA increased in the following order -HA-pH 2.0, HA-pH 4.0, HA-40 degrees C and HA-80 degrees C - with a corresponding decrease in the a/c intensity ratio. The BSA/LSA adsorption ratio increased with the a/c intensity ratio in the range of 3.3-8.9, and the BSA and LSZ were selectively adsorbed on HA, depending on the crystal shape., IOS PRESS
Bio-Med. Mat. Eng, 2013年, [査読有り] - Development of Cell Culture Microdevice Integrated with Piezoelectric Thin Film Actuator for On-Chip Regulation of Cell Functions
Takahiro Kawashima; Yuhei Yamada; Yuuta Matsuzawa; Moeto Nagai; Takayuki Shibata; Toru Masuzawa; Tsuyoshi Kimura; and Akio Kishida, To develop a cell culture microdevice integrated with piezoelectric thin film actuators for on-chip cell function regulation, we investigated various fabrication processes including the formation of a lead zirconate titanate (PZT) thin film using a sol-gel method as a piezoelectric thin film actuator and PZT thin film patterning. According to our proposed batch fabrication process, a prototype cell culture microdevice with 16 microchambers and PZT actuators was successfully fabricated on a 20 x 20mm(2) Si substrate. Moreover, we used the fabricated prototype device to investigate the effects of applied voltage and frequency on diaphragm displacement. The device sufficiently delivered mechanical vibratory stimuli to cells in culture solution. Moreover, in a feasibility study using living cells, we observed that mechanical vibratory stimulation affected cell adhesion. (C) 2012 The Japan Society of Applied Physics, JAPAN SOC APPLIED PHYSICS
Japanese Journal of Applied Physics, 2012年10月, [査読有り] - スパッタリング法を用いたストロンチウムアパタイト薄膜の作製と骨芽細胞による評価
星野智大; 尾関和秀; 後藤哲哉; 増澤徹; 青木秀希, バイオインテグレーション学会
バイオインテグレーション学会, 2012年08月, [査読有り] - Effect of metal surface characteristics on the adhesion performance of the integrated low-level energies method of adhesion
Aodai T; Masuzawa T; Ozeki K; Kishida A; Higami T
Journal of Artificial Organs, 2012年08月, [査読有り] - Development of Lorentz force type tilt control motor for rotary blood pumps
Ichinose T; Masuzawa T; Steinseifer U; Timms D
日本AEM学会誌, 2012年06月, [査読有り] - A radial type self-bearing motor for small maglev regenerative blood pump
Ukita K; Masuzawa T; Onuma H; Nishimura T; Kyo S
日本AEM学会誌, 2012年06月, [査読有り] - Miniaturized axial gap maglev motor with vector control for pediatric artificial heart
Osa M; Masuzawa T; Tatsumi E
日本AEM学会誌, 2012年06月, [査読有り] - Development of Cell Culture Microdevice Actuated by Piezoelectric Thin Films for Delivering Mechanical Vibratory Stimuli to Cells
Yuhei Yamada; Genki Umegaki; Takahiro. Kawashima; Moeto Nagai; Takayuki Shibata; Toru Masuzawa; Tsuyoshi Kimura; Akio Kishida
Journal of Physics: Conference Series, 2012年03月, [査読有り] - 人工心臓のための12突極ラジアル型磁気浮上モータにおける最適極数の検討
小沼弘幸; 浮田啓悟; 増澤徹
日本AEM 学会誌, 2012年03月, [査読有り] - 小型ローレンツ型磁気浮上モータのサーボモータ制御
岡田養二; 三好理文; 増澤徹; 榎園正人
日本AEM 学会誌, 2012年03月, [査読有り] - IPM型5軸制御セルフベアリングモータの永久磁石配置に関する研究
松田 健一; 佐藤 心平; 近藤 良; 増澤 徹, The 5-DOF self-bearing motor possesses the functions of a motor, two radial AMBs, and an axial AMB. Therefore, it is possible to miniaturize the AMB system with maintaining high performance. In this paper, an interior permanent magnet (IPM) type 5-DOF self-bearing motor is proposed. The IPM rotor generates bias fluxes to not only the radial direction but also the overhanging stator direction without side surface permanent magnets. Optimum configuration of the permanent magnets is analyzed using 3 dimensional finite element method. The results show the feasibility of the more compact and highly-reliable 5-DOF self-bearing motor., The Japan Society of Mechanical Engineers
日本機械学会論文集 C編, 2012年 - Development of Lorentz force type tilt control motor for rotary blood pumps
Takannori Ichinose; Toru Masuzawa; Ulrich Steinseifer; Daniel Timms
第20回MAGDAコンファレンスProceedings, 2011年11月 - Miniaturized axial gap maglev motor with vector control for pediatric artificial heart
Masahiro Osa; Toru Masuzawa; Eisuke Tatsumi
第20回MAGDAコンファレンスProceedings, 2011年11月 - BiVACORⓇ-A Magnetically levited biventricular artificial heart
Daniel Timms; Nobuyuki Kurita; Nicholas Greatrex; Toru Masuzawa
第20回MAGDAコンファレンスProceedings, 2011年11月 - 完全人工心臓用カスケードポンプ(ACCEL PUMP)の左心用ポンプの評価
福長一義; 阿部裕輔; 山家智之; 巽英介; 増澤徹; 山根隆志; 妙中義之; 井街宏; 舟久保昭夫; 福井康裕
人工臓器, 2011年10月, [査読有り] - 治療用人工心臓のためのアキシャル型磁気浮上モータの開発
北郷将史; 増澤徹; 西村隆; 許俊鋭
日本AEM学会誌, 2011年07月, [査読有り] - 乳児用人工心臓用ダブルステータ型磁気浮上モータの開発
長真啓,増澤徹,巽 英介
日本AEM学会誌, 2011年07月, [査読有り] - アウターロータ型5軸制御セルフベアリングモータの開発
松田 健一; 寺山 昌幸; 近藤 良; 増澤 徹
日本機械学会論文集C編, 2011年05月, [査読有り] - Synthetic polymer-tissue adhesion using an ultrasonic scalpel
Yamamoto K; Kimura T; Nam K; Funamoto S; Ito Y; Shiba K; Katoh A; Shimizu S; Kurita K; Higami T; Masuzawa T; Kishida A, Interface phenomena such as encapsulation and formation of dead space around implanted biomaterials lower biomaterial performance. To advance tissue adhesive technology, understanding the interactions between tissue (collagen) and polymer is indispensable. Adhesion between tissue and polymer was studied using an ultrasonically activated scalpel (UAS).
The Harmonic Scalpel was used as an ultrasonically activated scalpel for polymer and tissue adhesion. A piece of porcine aorta and a polymeric film were layered and placed between the blades of the Harmonic Scalpel. Then the samples were gripped with 20 kgf of force for 1-10 s to adhere the porcine aorta and polymeric films. The adhesion was characterized by macro- and microscopic observation, thermographic analysis, and measurement of bonding strength, static contact angle (SCA), and surface properties.
Cellulose, vinylon, polyethylene telephthalate, nylon, and Pellethane(A (R)) could be bonded to the aorta. Bonding was not observed for the polyethylene, polypropylene, polyvinyl chloride, or polytetrafluoroethylene. This suggests that the existence of functional groups such as hydroxyl, carbonyl, carboxyl, and amide groups in the polymer structure are key factors in adhesion. Harmonic Scalpel modification of the polyethylene surface during corona discharge treatment further indicated that the functional groups of the polymers are one of the essential factors for tissue adhesion. The temperatures of adhesion were 90-150A degrees C for the polymers, and the melting temperatures (Tm) were 193-306A degrees C. This suggests that adhesion was formed by the interaction between the melted polymer surface and the tissue collagen.
Both polar functional groups and adequate thermal characteristics are necessary for polymers to bond with tissues. These findings should be useful for the development of novel polymers that can be bonded to living tissues with UAS treatment, which can be applied for endoscopic surgery., SPRINGER
Surgical Endoscopy, 2011年04月, [査読有り] - Effects of vibration on differentiation of cultured PC12 cells
ItoY; KimuraT; NamKW; Kato A; Masuzawa T; Kishida A, Different types of physiological-mechanical stress, such as shear stress in vascular endothelial cells or hydrostatic pressure in chondrocytes are well known as regulators of cell function. In this study, the effects of vibration, a type of non-physiological mechanical stimulation, on differentiation of rat pheochromocytoma (PC12) cells are reported. A nano-vibration system was designed to produce nanometer-scale vibration. The frequency and amplitude of the nano-vibrations were monitored by a capacitance displacement sensor connected to an oscilloscope. When PC12 cells exposed to nerve growth factor were subjected to vibration at 10 kHz, differentiation and elongation of their neurites were promoted earlier in the culture. Vibration promoted differentiation of PC12 cells. This approach could therefore also be promising for determining of the effects of the physical environment on cell differentiation. Biotechnol. Bioeng. 2011;108: 592-599. (C) 2010 Wiley Periodicals, Inc., JOHN WILEY & SONS INC
Biotechnology & Bioengineering., 2011年03月, [査読有り] - Deodorisation effect of diamond-like carbon/titanium dioxide multilayer thin films deposited onto polypropylene
K.Ozeki; K.K.Hirakuri; T.Masuzawa
Applied Surface Science, 2011年02月 - サブミクロンプロセスで製造された2次元集積化磁気センサにおける感度特性に関する研究
木村孝之,古谷仁,増澤徹
映像情報メディア学会誌, 2011年, [査読有り] - Nano-vibration effect on cell adhesion and its shape
Yukiko Ito; Tsuyoshi Kimura; Yusuke Ago; Kwangwoo Nam; Kaori Hiraku; Kozo Miyazaki; Toru Masuzawa and Akio Kishida, Extracellular physical features of underlying the adhesive substrate affect cell adhesion to it substrate. In this study, the effects of vibration, a type of artificial physical stimulation, on the adhesion of mouse L929 cells, mouse embryonic fibroblasts (MEFs), HeLa cells and human umbilical vein endothelial cells (HUVECs) are reported. A nano-vibration system was designed to produce nanometer-scale vibration. When L929 cells, HeLa cells, and HUVECs were subjected to vibration at 100 Hz and 1 kHz, they were not affected. On the other hand, in MEFs, the adherent cells were increased and changed their shape remarkably in response to 1 kHz vibration. To investigate the MEFs' sensitivity to vibration in detail, the cells shape was classified into four types; round, stellate, filopodia-formed and lamellipodia-formed. In serum addition culture, 1 kHz vibration increased the number of filopodia-formed cells but decreased lamellipodia cells. Furthermore, the preliminary cDNA microarray experiments showed that expression of genes which regulate cytoskeleton were changed by vibration stimulation. These results suggest that vibration could affect cell adhesion and the determination cell shape., IOS PRESS
Bio-Medical Materials and Engineering, 2011年, [査読有り] - Feasibility Study of Cell Culture Microdevice actuated by Piezoelectric Thin Film for on-Chip Regulation of Cell Functions
Takahiro Kawashima; Takayuki Shibata; Moeto Nagai; Toru Masuzawa; Tsuyoshi Kimura; Akio Kishida
Proc. of The 14th International Conference on Miniaturized Systems for Chemistry and Life Sciences (μTAS 2010), 2010年10月, [査読有り] - アウターロータ型5軸制御セルフベアリングモータの開発
松田健一,寺山昌幸,近藤良,増澤徹
日本機械学会[No.10-8]Dynamics and Design Conference 2010 CD-ROM論文集, 2010年09月 - Development of Flux Concentrated type Self-Bearing Motor
Okada Y; Kitagou K; Masuzawa T; Enokizono M, Self-bearing motor has combined function of AC motor and magnetic bearing. Usually lévitation force is produced by Maxwell force while the motor torque is produced by Lorentz force. The authors have proposed Lorentz type self-bearing motor where strong magnetic flux is the key technology for good characteristics. In this paper three types of rotors are designed and compared: a flux concentrated PM rotor, Halbach rotors with iron back yoke and aluminum back yoke. The high density flat coils are designed and used for the stator. The experimental setup is fabricated and tested. The results obtained are compared and discussed in details. © 2010 IFAC., IFAC Secretariat
5th IFAC Symposium on Mechatronic Systems, 2010年09月 - Japanese guidance for ventricular assist devices/ total artificial hearts
Yamane T; Kyo S; Matsuda H; Abe Y; Imachi K; Masuzawa T; Nakatani T; Sase K; Tabayashi K; Takatani S; Tatsumi E; Umezu M, To facilitate research and development (R&D) and to expedite the review processes of medical devices, the Ministry of Health, Labor and Welfare (MHLW) and the Ministry of Economy, Trade and Industry (METI) founded a joint committee to establish guidance for newly emerging technology. From 2005 to 2007, two working groups held discussions on ventricular assist devices and total artificial hearts, including out-of-hospital programs, based on previous guidance documents and standards. Based on this discussion, the METI published the R&D Guidelines for innovative artificial hearts in 2007, and in 2008 the MHLW published a Notification by Director regarding the evaluation criteria for emerging technology., WILEY-BLACKWELL PUBLISHING, INC
Artificial Organs, 2010年09月, [査読有り] - Miniaturized Magnetically Levitated Motor for Pediatric Artificial Heart
Osa M; Masuzawa T; Tatsumi E
Proceedings the 12th International Symposium on Magnetic Bearings (ISMB 12), 2010年08月 - Axial Magnetic Bearing Development for the BiVACOR Rotary BiVAD/TAH
Greatrex NA; Timms DL; Kurita N; Palmer EW; Masuzawa T, A suspension system for the BiVACOR biventricular assist device (BiVAD) has been developed and tested. The device features two semi-open centrifugal impellers mounted on a common rotating hub. Flow balancing is achieved through the movement of the rotor in the axial direction. The rotor is suspended in the pump casings by an active magnetic suspension system in the axial direction and a passive hydrodynamic bearing in the radial direction. This paper investigates the axial movement capacity of the magnetic bearing system and the power consumption at various operating points. The force capacity of the passive hydrodynamic bearing is investigated using a viscous glycerol solution. Axial rotor movement in the range of +/- 0.15 mm is confirmed and power consumption is under 15.5 W. The journal bearing is shown to stabilize the rotor in the radial direction at the required operating speed. Magnetic levitation is a viable suspension technique for the impeller of an artificial heart to improve device lifetime and reduce blood damage., IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC
IEEE Transactions on Biomedical Engineering, 2010年03月, [査読有り] - 二次元集積化磁気センサのフレームレート向上に関する研究
木村孝之,横山裕大郎,増澤徹, To improve the frame rate of a two-dimensional integrated magnetic sensor, the pixel structure and readout circuits were re-examined. The frame rate was improved by reducing the noise of the horizontal shift register by lowering the drive frequency and parallel reading (with 16 channels). With this idea, two-dimensional integrated magnetic sensors were designed and fabricated with the standard 0.35 μm CMOS process on silicon. The type of Hall sensor is n-type Hall sensor that uses an inversion layer under the gate oxide of the MOSFET. The Hall sensors were arrayed (64×64), and the control digital circuits and output amplifier were also integrated into the same chip. "One pixel" was 50×50 μm, and the entire chip was 4.9×4.9 mm. The frame rate was 7813 frames/sec at a 2-MHz horizontal shift register frequency. The average sensitivity of these sensors was 72.9 mV/(mA·T). The two-dimensional magnetic flux distribution was measured with a 3000-rpm, 1-mm-diameter Nd-Fe-B rare-earth permanent rotating magnet without image lag. From the measurement results, a high frame-rate magnetic sensor for motor control was successfully fabicated., The Institute of Image Information and Television Engineers
映像情報メディア学会, 2010年03月, [査読有り] - Design and basic characteristics of permanent magnet hybrid type axial magnetic bearings
Nobuyuki Kurita; Youhei Takahashi; Takeo Ishikawa; Daniel Timms; Nicholas Greatrex; Toru Masuzawa, In order to improve rotor-impeller suspensi performance of the developing ventricular assist device, ax magnetic bearing with various permanent magnet arrangeme are designed and fabric stator shows wide l © 2010 IEEE.
Digests of the 2010 14th Biennial IEEE Conference on Electromagnetic Field Computation, CEFC 2010, 2010年, [査読有り] - Influence of the hydrothermal temperature and pH on the crystallinity of a sputtered hydroxyapatite film
Ozeki K; Aoki K; Masuzawa T, Hydroxyapatite (HA) was coated onto titanium substrates using radio frequency sputtering, and the sputtered films were crystallized under hydrothermal conditions at 110-170 degrees C at pH values of 7.0 and 9.5. The crystallite size, the remnant film thickness, and the surface morphology of the films were observed using X-ray diffraction, energy dispersive X-ray spectroscopy, and scanning electron microscopy, respectively.
The crystallite size increased with the process temperature, and reached 123.6 nm (pH 9.5 and 170 degrees C) after 24 h. All of the crystallite sizes of the film treated at pH 9.5 were higher than those treated at pH 7.0 at each process temperature. The film treated at pH 9.5 retained more than 90% of the initial film thickness at any process temperature. The ratio of the film treated at pH 7.0 did not reached 90% at less than 150 degrees C, and tended to increase with the process temperature. (C) 2010 Elsevier B.V. All rights reserved., ELSEVIER SCIENCE BV
Applied Surface Science, 2010年, [査読有り] - Adsorptive properties of albumin, fibrinogen, and gamma-globulin on fluorinated diamond-like carbon films coated on PTFE
Ozeki K; Magashima I; Hirakuri KK; Masuzawa T, Fluorinated diamond-like carbon (F-DLC) films were deposited on polytetrafluoroethylene (PTFE) using radio frequency (RF) plasma-enhanced chemical vapor deposition (CVD) by changing the ratio of tetrafluoromethane (CF(4)) and methane (CH(4)). To enhance the adhesion strength of the F-DLC film to the PTFE substrate, the PTFE surface was modified with a N(2) plasma pre-treatment. XPS analysis of the films showed that the C-C bond decreased with increases in the CF(4) ratio, whereas the C-F bond increased with the CF(4) ratio. The F/C ratio of the film also increased with the CF(4) ratio. The pull-out test showed that the adhesion strengths of the films (CF(4)-0-60%) were improved with the plasma pre-treatment. In the film without the plasma pre-treatment, adhesion strength increased with the CF(4) ratio. In contrast, in the case with the plasma pre-treatment, the adhesion strength of the F-DLC film decreased with the increased CF(4) ratio. Regarding the adsorption of albumin, fibrinogen, and gamma-globulin, the amount of adsorbed albumin on the film decreased with an increasing CF(4) ratio, and the amount of adsorbed fibrinogen and gamma-globulin increased with the CF(4) ratio. The CF(4)-0% DLC film showed the most adsorbed albumin and the least adsorbed fibrinogen and gamma-globulin. This indicates that the CF(4)-0% DLC film has higher anti-thrombogenicity than the F-DLC film., SPRINGER
J Mater Sci: Mater Med, 2010年 - The wear properties and adhesion strength of the diamond-like carbon film coated on SUS, Ti and Ni-Ti with plasma pre-treatment
Ozeki K; Masuzawa T; Hirakuri KK, Diamond-like carbon (DLC) films were deposited on stainless steel (SUS), titanium (Ti) and nickel titanium (Ni-Ti) substrates using a radiofrequency plasma chemical vapour deposition method. Prior to DLC coating, the substrates were exposed to O(2) and N(2) plasma to enhance the adhesion strength of the DLC film to the substrate. After the plasma pre-treatment, the chemical composition and the wettability of the substrate surface was investigated by X-ray photoelectron spectroscopy (XPS) and water contact angle measurement, respectively. A pull-out test and a ball-on-disc test were carried out to evaluate the adhesion strength and the wear properties of the DLC-coated substrates.
The XPS results showed that the N(2) and O(2) plasma pre-treatment produced nitride and oxide on the substrate surfaces, such as TiO(2), TiO, Fe(2)O(3), CrN and TiNO. In the pull-out test, the adhesion strengths of the DLC film to the SUS, Ti and Ni-Ti substrates were improved with the plasma pre-treatment. In the ball-on-disc test, the DLC coated SUS, Ti and Ni-Ti substrates without the plasma pre-treatment showed severe film failure following the test. The DLC coated SUS and Ni-Ti substrates with the N(2) plasma pre-treatment showed good wear resistance, compared with that with the O(2) plasma pre-treatment., IOS PRESS
Bio-Medical Materials and Engineering, 2010年, [査読有り] - Cross-sectional hydrogen content and mass density profiles of diamond-like carbon film by neutron and X-ray reflectivity
Ozeki K; Saitoh H; Takeda M; Ohgoe Y; Hirakuri KK; Yonemura M; Masuzawa T, The cross-sectional profiles of hydrogen content and mass density of diamond-like carbon (DLC) film were investigated using X-ray and neutron reflectivity. DLC films were prepared using a plasma CVD technique by varying the H(2)/(H(2) + CH(4)) ratio gas source from 0 to 0.9. The cross-sectional hydrogen content and mass density profiles of the films were calculated by neutron and X-ray reflectivity, and the results were compared with those from elastic recoil detection analysis (ERDA).
The fitted simulation showed that the mass density gradually decreased with increasing depth, whereas the hydrogen content increased with depth. In both ERDA and reflectivity measurements, the average hydrogen content was more than 30% in all films and tended to increase with the H(2)/(CH(4) + H(2)) ratio. However, there was a difference in hydrogen content values between the two analyses ranging from 5.1% to 8.5%. (C) 2009 Elsevier B.V. All rights reserved., ELSEVIER SCIENCE SA
Diamond & Related Materials, 2010年, [査読有り] - Development of tissue adhesion method using integrated low-level energies
Katoh A; Masuzawa T; Ozeki K; Kishida A; Kimura T; and Higami T, We have developed a method that allows biological tissues to be adhered together with minimal invasion by delivering integrated low-level energies from heat, pressure, and vibration. Tensile tests on adhered slices of porcine aorta were performed to determine the relationships between adhesive strength and conditions such as adhesion temperature, time, pressure, and vibration. The maximal adhesive shear tensile strength using the proposed method was 0.2 MPa, which is half the strength of the porcine aorta and stronger than surgical tissue adhesive. Adhesion strength increased in proportion to temperature, time, and pressure, and also in the presence of vibration, indicating that vibrational energy contributes to the adhesive mechanism and strength. Adhesive stability, the effect of heat on adhesive strength, and the ability of tissue to adhere to artificial materials were also clarified. (C) 2010 IPEM. Published by Elsevier Ltd. All rights reserved., ELSEVIER SCI LTD
Medical Engineering & Physics, 2010年, [査読有り] - 両心補助人工心臓BiVACOR Bi-VAD用磁気浮上モータ
増澤 徹; 佐々木瑛祐; ダニエル L ティムス, We have developed a new assist device BiVACOR for bi-ventricular support. In this paper, newly developed magnetically suspended motor for the BiVACOR is reported. BiVACOR has double pumps for left and right ventricular assist driven by single magnetically suspended motor (MSM). Flow difference between the left and the right pump is regulated by changing the amount of the second flow through blood gap between impeller top edge and pump casing by shifting the impeller position axially. New MSM has a combined core for magnetic bearing and motor. Both of the impellers are set at the both end of the integrated core. Back surface of the left pump impeller faced to the core side has permanent magnets to construct the hybrid magnetic bearing with the core that electric magnets for the magnetic bearing are constructed on. Permanent magnets for motor are set on back surface of the right pump impeller. Both impellers are connected rigidly with a center shaft through the center hall of the stator core. Attractive forces produced by the motor and the magnetic bearing are made balance to suspend the rotating impellers. The axial position of the impellers is adjusted with the magnetic bearing when the flow balance between the left and right pump is changed. Performance of the developed MSM as an actuator for BiVACOR was evaluated. The new MSM is rotated with levitation up to a rotating number of 4,800rpm. Vibration amplitude with a rotating number of 2,000rpm is only 27 micro meters and the axial position of the impeller is controllable in the range of 500 micro meters. The developed MSM has sufficient performance as an actuator of the BiVACOR., 日本AEM学会
日本AEM学会, 2010年, [査読有り] - Characterization of cell culture microdevice integrated with piezoelectric thin film actuator for delivering mechanical vibratory stimuli to cells
Kawashima T; Matsuzawa Y; Shibata T; Nomura M; Masuzawa T; Kishida A
Proc. of 3rd International Conference of Asian Society for Precision Engineering and Nanotechnology (ASPEN2009), 2E-13 (in CD-ROM, 4pp), 2009年11月, [査読有り] - 5-DOF Controlled Self-Bearing Motor
Ishikawa T; Matsuda K; Kondo R; Masuzawa T, A novel 5-DOF actively controlled self-bearing motor that combines the functions of a motor, two radial AMBs, and an axial AMB has been developed to achieve smaller size and higher performance simultaneously. In this paper, magnetic suspension performance of the 5-DOF controlled self-bearing motor is reported. First, radial control performance of the developed self-bearing motor is evaluated by the radial experimental setup. Next, tilt control performance and 5-DOF active control performance are evaluated by the 5-DOF experimental setup. Finally, the frequency response in the 5-DOF is measured with the contact-free levitation. The 5-DOF controlled self-bearing motor produced sufficient radial force and tilt control torque to overcome the radial negative stiffness and to stabilize the rotor. The sufficient frequency bandwidth was observed in the frequency response and the self-bearing motor successfully suppressed vibration at the resonant frequencies., The Japan Society of Mechanical Engineers
Journal of System Design and Dynamics, 2009年07月, [査読有り] - 4軸制御型磁気軸受を用いた磁気浮上クリーンポンプの研究開発
黒須寛秋; 増澤徹; 加藤綾子; 小沼弘幸,柿原功一, A new hybrid magnetic bearing and motor system with wide air gaps has been developed, and a magnetically suspended clean pump with the system has been developed. The optimization method to determine the optimal values of the design parameters has been developed based on magnetic equivalent circuit technique, genetic algorithm and three dimensional magnetic field analysis. The size of the hybrid magnetic bearing C core, the thickness of the permanent magnets, and the turn number of the electromagnets are optimized by the method. The developed system has an outer diameter of 100mm, a length of 140mm, and air gaps of 3.5mm. And the developed pump has an outer diameter of 100mm, a length of 160mm. The measured ratio of force to excitation current is 36.4N/A. The rotor-impeller could be driven up to a rotational speed of 6000rpm without touching anywhere. The developed pump indicates sufficient pump performances which are maximum pump head of 9.37mH_2O and maximum flow rate of 27.3L/min., 日本AEM学会
日本AEM学会, 2009年06月, [査読有り] - Estimation of changes in dynamic hydraulic force in a magnetically suspended centrifugal blood pump with transient computational fluid dynamics analysis
Masuzawa T; Ohta A; Tanaka N; Qian Y; Tsukiya T, The effect of the hydraulic force oil magnetically levitated (maglev) pumps should be studied carefully to improve the suspension performance and the reliability of the pumps. A maglev centrifugal pump, developed at Ibaraki University, was modeled with 926376 hexahedral elements for computational fluid dynamics (CFD) analyses. The pump has a fully open six-vane impeller with a diameter of 72.5 mm. A self-bearing motor suspends the impeller in the radial direction. The maximum pressure head and flow rate were 250 mmHg and 141/min, respectively. First, a steady-state analysis was performed using commercial code STAR-CD to confirm the model's suitability by comparing the results with the real pump performance. Second, transient analysis was performed to estimate the hydraulic force on the levitated impeller. The impeller was rotated in steps of 1 degrees using a sliding mesh. The force around the impeller was integrated at every step. The transient analysis revealed that the direction of the radial force changed dynamically as the vane's position changed relative to the outlet port during one circulation, and the magnitude of this force was about 1N. The current maglev pump has sufficient performance to counteract this hydraulic force. Transient CFD analysis is not only useful for observing dynamic flow conditions in a centrifugal pump but is also effective for obtaining information about the levitation dynamics of a maglev pump., SPRINGER TOKYO
J. Artificial Oragans, 2009年, [査読有り] - Gas barrier properties of diamond-like carbon films coated on PTFE
Ozeki K; Magashima I; Ohgoe Y; Hirakuri KK; Mukaibayashi H; Masuzawa T, Diamond-like carbon (DLC) films were deposited on polytetrafluoroethylene (PTFE) using radio frequency (RF) plasma-enhanced chemical vapour deposition (PE-CVD). Before the DLC coating, the PTFE substrate was modified with a N(2) plasma pre-treatment to enhance the adhesive strength of the DLC to the substrate. The influences of the N(2) plasma pre-treatment and process pressure on the gas permeation properties of these DLC-coated PTFE samples were investigated. In the Raman spectra, the G peak position shifted to a lower wave number with increasing process pressure. With scanning electron microscopy (SEM), a network of microcracks was observed on the surface of the DLC film without N(2) plasma pre-treatment. The density of these cracks decreased with increasing process pressure. In the film subjected to a N(2) plasma pre-treatment, no cracks were observed at any process pressure. In the gas barrier test, the gas permeation decreased drastically with increasing film thickness and saturated at a thickness of 0.2 mu m. The DLC-coated PTFE with the N(2) plasma pre-treatment exhibited a greater reduction in gas permeation than did the samples without pre-treatment. For both sample types, gas permeation decreased with increasing process pressure. (C) 2009 Elsevier B. V. All rights reserved., ELSEVIER SCIENCE BV
Applied surface science, 2009年, [査読有り] - Development of a cost effective gap sensor for magnetic bearings
Okada Y; Ishikawa T; Masuzawa T; Kondo R
日本AEM学会, 2009年 - Adsorptive property of albumin and streptokinase on sputtered hydroxyapatite film and its antithrombogenicity
Yoshihara H; Ozeki K; Masuzawa T; Aoki H
Applied Surface Science, 2008年08月, [査読有り] - 5軸能動制御型セルフベアリングモータの開発
松田健一,石川達也,増澤徹,近藤良, This paper proposes a novel self-bearing motor. The rotor of the proposed self-bearing motor has the side surface permanent magnets with the conventional circumferential surface permanent magnets. The overhanging stator is newly fixed to the outside of the original stator core. This joined stator core can generate axial direction force effectively to the integrated rotor. The principle of the axial control force and the tilting control torque generation is shown and the general solutions of the force and the torque are also presented. The fundamental characteristics of the self-bearing motor are analyzed by 3-dimensional magnetic field analysis using finite element method. The results show the high feasibility of the 5-axis active control type self-bearing motor., 日本AEM学会
日本AEM学会, 2008年, [査読有り] - 5-DOF Controlled Self-Bearing Motor
Ishikawa T; Matsuda K; Masuzawa T; Kondo R
Proceedings of the 11th International Symposium on Magnetic Bearings, 2008年 - Wide gap magnetic bearing system for a magnetically suspended clean pump
Kurosu H; Masuzawa T; Katoh A; Suzuki K; Onuma H; Kakihara K
Proceedings of the 11th International Symposium on Magnetic Bearings, 2008年 - Photolithography system with liquid crystal display as active gray-tone mask for 3D structuring of photoresist
Hayashi T; Shibata T; Kawashima T; Makino E; Mineta T; Masuzawa T, Layer manufacturing is generally utilized for the development of micro electromechanical systems (MEMS) and micro total analysis systems (mu TAS). However, the preparation of multiple masks and repetitive exposure procedure prevents the rapid fabrication of 3D microstructures. An active mask fabrication by using a liquid crystal display (LCD) as an electrically controllable photomask can simplify the layer manufacturing process. In addition, the gray-tone photolithography is available by using LCD lithography system, since the exposure distribution is easily controlled by an LCD. We have developed the LCD mask exposure system by using UV light source. Firstly, the patterning characteristics of the UV photoresist by exposing line and space patterns are evaluated, and then, a fundamental step shape is produced in order to verify the feasibility of gray-tone UV photolithography by using LCD. A shape with a different height can be fabricated without any repetitive exposure and development procedures. Finally, we confirmed the high patterning resolution such as 11 mu m using check patterns and fabricated 3D step shapes by using the LCD as a gray-scale photomask. (C) 2008 Elsevier B.V. All rights reserved., ELSEVIER SCIENCE SA
Sensors and Actuators A, 2008年, [査読有り] - Axial magnetic bearing developments for the Bivacor rotary BIVAD/TAH
Kurita N; Timms D L; Masuzawa T; Greatrex N; Masuzawa T
Proceedings of the 11th International Symposium on Magnetic Bearings, 2008年, [査読有り] - Development of a novel hybrid type magnetic bearing and application to small impeller centrifugal pump for artificial hearts
Takashi Saitoh; Toru Masuzawa; Naohisa Nakayama, We have developed a new hybrid magnetic(HM)bearing system for durable and small size artificial hearts. A prototype maglev pump was also developed to verify the feasibility of the developed HM bearing system. A small impeller centrifugal pump was combined with the HM bearing for the prototype pump. The impeller is levitated by a set of HM bearings at both sides of the impeller. A motor stator is set at the center of the device to rotate the levitated impeller. Maximum rotating speed with complete levitation in the air is15, 000rpm. Maximum oscillation amplitude in the radial direction is 0. 04mm with a target rotating number of5, 000rpm. The developed HM bearing system indicated sufficient levitation performance for the artificial heart and the magnetically levitated centrifugal pump with small impeller also displayed good pump performance as a ventricular assist system., The Society of Life Support Engineering
ライフサポート, 2006年12月, [査読有り] - Characteristics of a two-dimensional integrated magnetic sensor for position sensing and motor control
K Takasaki; T Masuzawa, Two-dimensional integrated magnetic sensors for position sensing were designed and fabricated with the standard 0.35-mu m CMOS process on silicon. One such type is the n-type Hall sensor that uses an inversion layer under the gate oxide of the MOSFET. The Hall sensors were arrayed (64 x 64), and the control digital circuits and output amplifier were also integrated into the same chip. 'One pixel' was 50 x 50 mu m, and the entire chip was 4.9 x 4.9 mm. The sensitivity of one of these sensors was 2.7 mV/(mA.kG). The two-dimensional magnetic flux distribution was measured from the 5-mm diameter Nd-Fe-B rare-earth permanent magnet. About 42 s was required to measure one frame. The position of the magnet could be detected with the fabricated sensors. Magnetic sensors using an inversion layer in MOSFETs are useful for position sensing systems, but their noise characteristics, such as poor sensitivity, should be improved. (c) 2006 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc., WILEY
IEEJ Trans, 2006年08月 - Characteristics of a two-dimensional integrated magnetic sensor for position sensing and motor control
Takayuki Kimura; Keigo Takasaki; Toru Masuzawa, WILEY
IEEJ TRANSACTIONS ON ELECTRICAL AND ELECTRONIC ENGINEERING, 2006年08月 - Hemolysis resulting from surface roughness under shear flow conditions using a rotational shear stressor
Nishida M; Yamane T; Oshima I; Adachi Y; Masuzawa T, The degree of hemolysis as a function of surface roughness value and roughened area under shear flow conditions was investigated using a rotational shear stressor. The shearing portion of the stressor is cone shaped in its upper and lower positions, with a cylindrical central section. Surface roughness was applied to the cylindrical section. Bovine blood was sheared for 30 min over a set of roughened surfaces of between arithmetic mean roughness (Ra) 0.1 and 0.8 mm covering 10% of the surface area of the cylindrical section (equivalent to 1.8% of the whole blood contact area) at a shear rate of 3750/s. The threshold value thus obtained for rapid increase in hemolysis was between Ra 0.6 and 0.8 mm. When sheared with a roughened surface of Ra 0.8 mm applied to the cylindrical surface at areas between 0 and 100% (equivalent to between 0 and 18% of the whole blood-contacting area), the hemolysis level did not increase from 10 to 100%, but a significant difference was obtained between 0 and 10%. This suggests that red blood cells were destroyed not by fatigue failure caused by rolling on the roughened surface, but due to the high shear stress generated by surface roughness. Moreover, it appears that the shear stress was generated over the entire cylindrical section, regardless of the area of surface roughness., BLACKWELL PUBLISHING
Artificial organs, 2006年 - Novel maglev pump with a combined magnetic bearing
Onuma H; Murakami M and Masuzawa T, The newly developed pump is a magnetically levitated centrifugal blood pump in which active and passive magnetic bearings are integrated to construct a durable ventricular assist device. The developed maglev centrifugal pump consists of an active magnetic bearing, a passive magnetic bearing, a levitated impeller, and a motor stator. The impeller is set between the active magnetic bearing and the motor stator. The active magnetic bearing uses four electromagnets to control the tilt and the axial position of the impeller. The radial movement of the levitated impeller is restricted with the passive stability dependent upon the top stator and the passive permanent magnetic bearing to reduce the energy consumption and the control system complexity. The top stator was designed based upon a magnetic field analysis to develop the maglev pump with sufficient passive stability in the radial direction. By implementing this analysis design, the oscillating amplitude of the impeller in the radial direction was cut in half when compared with the simple shape stator. This study concluded that the newly developed maglev centrifugal pump displayed excellent levitation performance and sufficient pump performance as a ventricular assist device., LIPPINCOTT WILLIAMS & WILKINS
ASAIO Journal, 2005年01月, [査読有り] - アキシャル型磁気浮上モータを用いた人工心臓用遠心ポンプの開発
小沼弘幸,加藤勇,増澤徹, The lifetime of a rotary blood pump as an artificial heart is mainly determined by the durability of mechanical parts such as bearings and seals. The purpose of this study is to develop a durable centrifugal blood pump with self-bearing motor techniques. A magnetically suspended centrifugal blood pump by using an axially levitated motor is reported. The axially levitated motor consists of a top stator, a levitated rotor, a bottom stator, and a permanent magnet bearing. The levitated rotor is set between the top and the bottom stator. The axial position of the rotor is controlled by using the electromagnets. The maximum head pressure and the maximum flow rate of the magnetically suspended centrifugal pump were 200 mmHg and 81/min, respectively. The developed pump displayed good magnetic suspension performance and sufficient pump performance as a ventricular assist device., 一般社団法人日本機械学会
日本機械学会論文集(C編), 2005年01月, [査読有り] - 離散要素法を用いた微小循環内の血流シミュレーション
岩田賢; 田中伸厚; 増澤徹
ライフサポート, 2005年, [査読有り] - Hemolysis caused by surface roughness under shear flow
Numata Y; Nishida M; Yamane T; Oshima I; Adachi Y; Masuzawa T, In this study, the relationship between the degree of roughness of blood contact surfaces under laminar shear flow conditions and the level of hemolysis resulting from this roughness was investigated using a rotational shear stressor. Unlike previous in vitro experiments that used a pumped circuit, the level of hemolysis was directly evaluated under a constant shear flow. In total, 1.8% of the blood contact area was roughened to an arithmetic mean roughness (Ra) value of between 0.4 and 9.2μm by machine processing and a shear load was applied for 30min at a shear flow rate of 3750s-1. As a result, the threshold Ra value for the induction of hemolysis was found to be between 0.4 and 0.8μm. In addition, the results of this experiment suggested that the high shear stress resulting from surface roughness plays a major role in determining the level of hemolysis caused by surface roughness. © The Japanese Society for Artificial Organs 2005.
J Artif Organs, 2005年 - 液晶アクティブマスクを用いたDNAチップ合成システムの開発
柴田 隆行; 林 照剛; 能田 高行; 増澤 徹; 牧野 英司, The Society of Life Support Engineering
ライフサポート, 2004年 - 径方向支持型磁気浮上モータを使用した人工心臓用遠心ポンプの改良
小沼 弘幸; 増澤 徹; 岡田 養二; 築谷 朋典; 妙中 義之, The Society of Life Support Engineering
ライフサポート, 2004年 - 人工心臓のための超小型磁気浮上システムの開発
齋藤 喬; 増澤 徹; 岡田 養二; 小沼 弘幸; 児嶋 次郎, The Society of Life Support Engineering
ライフサポート, 2004年 - Axial type self-bearing motor for axial flow blood pump
Okada Y; Masuzawa T; Matsuda K; Ohmori K; Yamane T; K onishi Y; Fukahori S; Ueno S; Kim S-J, An axial self-bearing motor is proposed which can drive an axial blood pump without physical contact. It is a functional combination of the bi-directional disc motor and the axial active magnetic bearing, where it actively controls single degree-of-freedom motion, while other motions such as lateral vibration are passively stable. For application to a blood pump, the proposed self-bearing motor has the advantages of simple structure and small size. Through the finite element method (FEM) analysis and the experimental test, its good feasibility is verified. Finally, the axial flow pump is fabricated using the developed magnetically suspended motor. The pump test is carried out and the results are discussed in detail., BLACKWELL PUBLISHING INC
Artificial Organs, 2003年10月 - Magnetically suspended centrifugal blood pump with an axially levitated motor
Masuzawa T; Ezoe S; Kato T; Okada Y, The longevity of a rotary blood pump is mainly determined by the durability of its wearing mechanical parts such as bearings and seals. Magnetic suspension techniques can be used to eliminate these mechanical parts altogether. This article describes a magnetically suspended centrifugal blood pump using an axially levitated motor. The motor comprises an upper stator, a bottom stator, and a levitated rotor-impeller between the stators. The upper stator has permanent magnets to generate an attractive axial bias force on the rotor and electric magnets to control the inclination of the rotor. The bottom stator has electric magnets to generate attractive forces and rotating torque to control the axial displacement and rotation of the rotor. The radial displacement of the rotor is restricted by passive stability. A shrouded impeller is integrated within the rotor. The performance of the magnetic suspension and pump were evaluated in a closed mock loop circuit filled with water. The maximum amplitude of the rotor displacement in the axial direction was only 0.06 mm. The maximum possible rotational speed during levitation was 1,600 rpm. The maximum pressure head and flow rate were 120 mm Hg and 7 L/min, respectively. The pump shows promise as a ventricular assist device., BLACKWELL PUBLISHING INC
Artificial Organs, 2003年07月 - 小型電気油圧式アクチュエータを用いた補助人工心臓の開発
佐久間剛太; 増澤徹; 塚原金二; 土本勝也
ライフサポート, 2003年01月 - マイクロカプセル模擬血液の剪断応力による破壊特性
丸山 修; 山根隆志; 西田正浩; 筒井達夫; 軸屋智昭; 小野口富夫; 岩崎友美; 増澤徹, Microcapsule suspensions substituted for animal blood were designed as model blood for hemolysis tests of circulatory artificial organs. They included microcapsules, which were likened to erythrocytes, for main components of the suspensions .In this paper, we used two types of microcapsules, whose membrane materials were polyurethane and melamine resin respectively, and the both target sizes were 100μm in diameter. The fractural properties of the capsules in the suspensions were tested under the shear stress, generated by the rotational shear stressor. Flow patterns in the shear stressor were examined with an oil spot method. Polyurethane-capsule suspension showed similar fractural behavior to the bovine blood results under the rotational shear stressor. However, the behavior of melamine-capsule suspensions was different from the bovine blood, though the destructive sensitivity was higher than that of polyurethane-capsule suspension. We conclude that both suspensions with 100μm diameter can be candidates of standard hemolysis test solutions., The Society of Life Support Engineering
ライフサポート, 2002年12月 - Magnetically suspended centrifugal blood pump with a self-bearing motor
Masuzawa T; Onuma H; Kim SJ; Okada Y, A magnetically suspended centrifugal blood pump with a self bearing motor has been developed for long-term ventricular assistance. A rotor of the self bearing motor is actively suspended and rotated by an electromagnetic field without mechanical bearings. Radial position of the rotor is controlled actively, and axial position of the rotor is passively stable within the thin rotor structure. An open impeller and a semiopened impeller were examined to determine the best impeller structure. The outer diameter and height of the impeller are 63 and 34 mm, respectively. Both the impellers indicated similar pump performance. Single volute and double volute structures were also tested to confirm the performance of the double volute. Power consumption for levitation and radial displacement of the impeller with a rotational speed of 1,500 rpm were 0.7 W and 0.04 mm in the double volute, while those in the single volute were 1.3 W and 0.07 mm, respectively. The stator of the self bearing motor was redesigned to avoid magnetic saturation and improve motor performance. Maximum flow rate and pressure head were 9 L/min and 250 mm Hg, respectively. The developed magnetically suspended centrifugal blood pump is a candidate for an implantable left ventricular assist device., LIPPINCOTT WILLIAMS & WILKINS
ASAIO Journal, 2002年07月 - An ultradurable and compact rotary blood pump with a magnetically suspended impeller in the radial direction
Masuzawa T; Kita Y; Okada Y, A magnetically suspended centrifugal blood pump has been developed with a self-bearing motor for long-term ventricular assist systems. The rotor of the self-bearing motor is not only actively suspended in the radial direction, but also is rotated by an electromagnetic field, The pump has a long lifetime because there are no mechanical parts such as seals and motor bearings. An outer rotor mechanism was adopted for the self-bearing motor. The stator was constructed in the central space of the motor. The rotor shaped thin ring was set at the circumferential space of the stator. Six vanes were extended from the upper surface of the rotor toward the center of the pump to construct an open-type impeller. The outer diameter and the height of the impeller are 63 mm and 34 mm. respectively. The magnetic bearing method and the servomotor mechanism were adopted to levitate and rotate the rotor, Radial movements of the rotor and rotation are controlled actively by using electromagnets in the stator. Axial movement and tilt of the rotor are restricted by passive stability to simplify the control. The radial gap between the rotor and the stator is 1 mm. A closed-loop circuit filled with water was used to examine basic performance of the pump. Maximum flow rate and pressure head were 8 L/min and 200 mm Hg, respectively. Maximum amplitude of radial displacement of the impeller was 0.15 mm. The impeller could be suspended completely without touching the casing wall during the entire pumping process. Power consumption of the pump was only 9.5 W to produce a flow rate of 5 L/min against a pressure head of 100 mm Hg. We conclude that the pump has sufficient performance for the implantable ventricular assist system., WILEY-BLACKWELL
Artificial Organs, 2001年05月 - Development and chronic in vivo testing of an electrohydraulic totally implantable artificial heart system
Eisuke Tatsumi; Yoshiuki Taenaka; Akihiko Homma; Knihiro Uesho; Tomohiro Nishinaka; Tomonori Tsukiya; Hisateru Takano; Toru Masuzawa; Makoto Nakamura; Kohji Koshiji; Kinji Tsukahara; Katsuya Tsuchimoto; Hideki Wakui, The results of in vivo evaluation of electrohydraulic totally implantable artificial heart (EHTAH) systems were presented. To improve thrombo-resistant property, optimization of blood pump shapes from the hydrodynamic viewpoint were implemented according to the results of a novel flow visualization technique. The EHTAH system demonstrated an excellent anatomic fit and satisfactory in vivo performance represented by the successful sustainment of an animal's blood circulation for over 12 weeks.
American Society of Mechanical Engineers, Bioengineering Division (Publication) BED, 2001年 - Noninvasive assessment method to determine the anatomic compatibility of an implantable artificial heart system
B Zhang; E Tatsumi; Y Taenaka; H Takano; T Masuzawa, To assess the anatomic compatibility of an artificial heart (AH), we attempted to develop a computer environment that would facilitate a reliable simulation of an AH implanted in the human thorax. A three-dimensional thoracic computer model with a ventricle-resected heart was constructed, by using manually extracted contour points of the aorta, pulmonary artery, atria, atrioventricular valves, diaphragm, and thoracic wall from a set of consecutive CT images. Such a model enabled simulation of an AH implantation by orienting the AH model in it. Error evaluation on CT imaging and contour extraction with a Plexiglas cylindrical phantom showed that the diameter of the extracted phantom contour was approximately 2 mm smaller than its original with a standard deviation of < 0.5 mm. Errors in contour and surface reconstruction could be reduced to far less than 1 mm under constrained conditions. A study on the influence of breathing revealed that variations in some thoracic dimensions between inspiration and expiration could reach 10 mm. In summary, computer simulation of AH implantation is a worthwhile approach with acceptable accuracy, although further considerations of extreme thoracic situations will be required., LIPPINCOTT WILLIAMS & WILKINS
ASAIO JOURNAL, 2000年09月, [査読有り] - Magnetically suspended rotary blood pump with radial type combined motor-bearing (jointly authored)
Masuzawa T; Kita T; Matsuda K; Okada Y, A magnetically suspended centrifugal blood pump is being developed with a combined motor-bearing for long-term ventricular assist systems. The combined motor-bearing actively suspends a rotor in a radial direction to deal with radial force unbalance in the pump and rotates the rotor by using the electric magnetic field. Therefore, the pump has no mechanical parts such as bearings of the motor and has a long lifetime. The developed pump consists of a thin rotor with a semi open-type 6 vane impeller and a stator to suspend and rotate the rotor. The rotor has 4-pole permanent magnets on the circumferential surface. The outer diameter and the thickness of the rotor are 60 mm and 8 mm, respectively. Axial movement and tilt of the rotor are restricted by passive stability based on the thin rotor structure. Radial movements of the rotor, such as levitation in radial direction and rotation, are controlled actively by using electric magnets of the stator. The electric magnet coils to produce levitation and rotation forces are constructed on the periphery stator. The p +/- 2-pole algorithm and the synchronous motor mechanism are adopted to levitate and rotate the rotor. The radial gap between the rotor and the stator is 1 mm. A closed-loop circuit filled with water was connected to the developed pump to examine the basic performance of the pump and the magnetic suspension system. Maximum rotational speed, flow rate, and head were 2,800 rpm, 11 L/min, and 270 mm Hg, respectively. The rotor with the impeller could be suspended completely during the entire pumping process. We conclude the pump with the combined motor-bearing has sufficient performance for the blood pump., WILEY-BLACKWELL
Artificial Organs, 2000年06月 - 酸素消費量モニタを利用した全人工心臓の流量制御法の開発
中村真人; 本間章彦、高谷節雄、大内克洋、坂本徹、上所邦広、巽英介、妙中義之、増澤 徹
循環制御, 2000年04月 - Progress of an electrohydraulic total artificial heart system with a separate energy converter
Masuzawa T; Tatsumi E; Taenaka Y; Nakamura M; Endo S; Takano H; Koshiji K; Fukui Y; Murai T; Tsukahara K, We have been developing an electrohydraulic total artificial heart (EHTAH) system. The system consists of diaphragm blood pumps, an abdominally placed energy converter, an internal controller, a transcutaneous energy transfer (TET) system, a transcutaneous optical information transfer system, and internal and external lithium-ion (Li-ion) batteries. The energy converter was optimized to obtain better oil transfer. Maximum cardiac output and efficiency of the EHTAH were increased from 8 L/min to 10 L/min and from 10% to 12%, respectively. The volume of the energy converter was reduced from 280 to 210 ml. The pumping unit was successfully implanted in 68-85 kg calves without anatomic problems, and the calves survived up to 10 days with good circulatory results. The maximum temperature rise of the implanted energy converter was only 1 degrees C. Stable performance of the TET system was confirmed in goats for more than 1 month. DC-DC energy transfer efficiency with 20 W of energy transmission remained within the range of 80% to 85%, and no significant temperature rise was observed in the implanted circuit. The internal Li-ion battery was also evaluated in a goat, and the maximum temperature rise during the charging period was 1.5 degrees C, while the charging and discharging times were 72 and 58 min, respectively. We conclude that our system has progressed in its development as a practical implantable system., LIPPINCOTT WILLIAMS & WILKINS
ASAIO Journal, 1999年09月 - Control of a total artificial heart using mixed venous oxygen saturation
Nakamura M; Masuzawa T; Tatsumi E; Taenaka Y; Ohno T; Nakamura T; Zhang B; Kakuta Y; Nakatani T; Takano H, We developed a control of the total artificial heart (TAH) using mixed venous oxygen saturation (SvO(2)). With this method, the TAH output was controlled by automatically adjusting drive parameters in response to changes in measured SvO(2). The feasibility and validity of this method were evaluated in a series of treadmill exercise tests using a calf implanted with a pneumatic TAH. The cardiac output (CO) and SvO(2) were measured with an ultrasonic flowmeter and an oximetric catheter, respectively. The calf performed graded exercise under a fixed drive control mode (fixed mode), in which the drive parameters were unchanged throughout the treadmill test and under the SvO(2) based control mode (SvO(2) mode). The calf could go to Stage 6 in both modes, but the maximal oxygen consumption in the SvO(2) mode was 1.5 times as large as that of the fixed mode. Compared with the fixed mode, CO was increased effectively in the SvO(2) mode, and the capacity for exercise was augmented. When considering the relationship between oxygen consumption and oxygen delivery, it was revealed that the CO in the SvO(2) mode responded more adequately to the recipient's oxygen demand than that in the fixed mode. We conclude that this SvO(2) based control method is feasible and physiologically effective., LIPPINCOTT WILLIAMS & WILKINS
ASAIO Journal, 1999年09月 - Development of design methods for a centrifugal blood pump with a fluid dynamic approach : Results in hemolysis tests (jointly authored)
Masuzawa T; Tsukiya T; Endo S; Tatsumi E; Taenaka Y; Takano H; Yamane T; Nishida M; Asztalos B; et al, The purpose of this study was to examine the relationship between local flow conditions and the hemolysis level by integrating hemolysis tests, flow visualization, and computational fluid dynamics to establish practical design criteria for centrifugal blood pumps with lower levels of hemolysis. The Nikkiso centrifugal blood pump was used as a standard model, and pumps with different values of 3 geometrical parameters were tested. The studied parameters were the radial gap between the outer edge of the impeller vane and the casing wall, the position of the outlet port, and the discharge angle of the impeller vane. The effect of a narrow radial gap on hemolysis was consistent with no evidence that the outlet port position or the vane discharge angle affected blood trauma in so far as the Nikkiso centrifugal blood pump was concerned. The radial gap should be considered as a design parameter of a centrifugal blood pump to reduce blood trauma., WILEY-BLACKWELL
Artificial Organs, 1999年08月 - Three-dimensional thoracic modeling for an anatomical compatibility study of the implantable total artificial heart
Zhang B; Masuzawa T; Tatsumi E; Taenaka Y; Uyama C; Takano H; Takamiya M, Anatomical compatibility with the thoracic cavity is important in developing a completely implantable total artificial heart (TAH). The purpose of this study was to examine the optimal morphology of our TAH and to develop a computer implantation simulation environment for preoperational discussion. As the first stage, we constructed a prototype simulation system by creating a 3-D surface model of a thoracic cavity and one of a TAH. In this system, the thoracic surface model, composed of the aorta, pulmonary artery, ventricle resected heart, diaphragm, and thoracic wall, was created based on the organ contours extracted from electrocardiogram (ECG)-synchronized ultrafast computer tomographic images. The accuracy of the thoracic model was discussed using a phantom. The fitting study can be performed on the computer with the model of the thorax and that of the TAH. In the future, construction of a database for the thoracic cavities of heart failure patients is planned to improve the morphology of the TAH., BLACKWELL SCIENCE INC
Artificial Ogans, 1999年03月 - The development of a control method for a total artificial heart using mixed venous oxygen saturation
Nakamura M; Masuzawa T; Tatsumi E; Taenaka Y; Nakamura T; Zhang B; Nakatani T; Takano H; Ohno T, For physiological control of a total artificial heart (TAH), applying mixed venous oxygen saturation (Svo(2)) as a parameter for TAH control is a promising approach regarding sensitivity to the recipient's oxygen demand and the practical possibility of continuous monitoring using near infrared rays through transparent blood pump housings. To develop a control method for the TAH using Svo(2), the relationship between Svo(2) and cardiac output (CO) was investigated in a normal calf, and a control algorithm was developed based on this correlation. Then the feasibility of this method (Svo(2) mode) was evaluated in a calf implanted with a pneumatic TAH and compared with the fixed drive control mode (fixed mode) in which the drive parameters were unchanged. The calf performed a graded exercise test in both modes. The CO was effectively increased from 7.3 to 13.0 L/min in the Svo(2) mode, and the capacity for exercise was augmented compared to the fixed mode. We conclude that this Svo(2) mode is feasible and may be effectively applied in TAH control., BLACKWELL SCIENCE INC
Artificial Organs, 1999年03月 - In vivo evaluation of the National Cardiovascular Center electrohydraulic total artificial heart
Tatsumi E; Masuzawa T; Nakamura M; Taenaka Y; Nishimura T; Endo S; Zhang B; Kakuta Y; Nakata M; Nakamura T; Nishinak T; Takano H; Tsukahara K; Tsuchimoto K, We have been developing an electrohydraulic total artificial heart system. The system comprises an intrathoracic pumping unit composed of diaphragm type ellipsoidal blood pumps and an energy converter in addition to an electronics unit. The in vivo performance of the pumping unit was evaluated in a series of animal implantations with 3 calves weighing 62-85 kg. An interatrial shunt 4.5 mm in diameter was made in the atrial septum to compensate left-right imbalance. Two calves died early postoperatively, one of external controller power failure and the other of interatrial shunt stenosis due to thrombus formation. One calf, however, survived over 10 days under stable circulatory conditions. No abnormality was found in the oxygen metabolic condition or in major organ functions. The generation and dissipation of heat from the device was acceptable. This animal died of device malfunction caused by energy converter bearing breakdown. The device demonstrated a good anatomic fit without compromising the great vessels and adjacent tissues. It is concluded that the pumping unit has a sufficient in vivo basic performance although appropriate countermeasures are to be implemented against the detected problems concerning mechanical durability and interatrial shunt patency., BLACKWELL SCIENCE INC
Artificial Organs, 1999年03月 - 混合静脈血酸素飽和度に基づいた全人工心臓流量制御法の開発
中村真人; 巽 英介,増澤 徹,妙中義之,大野 孝,上所邦広,角田幸秀,張 斌,中村知道
人工臓器, 1999年03月 - Selection of a rechargeable internal back-up battery for a totally implantable artificial heart
Hiroyuki Honda; Kenji Shiba; Eimei Shu; Kohji Koshiji; Takeji Murai; Tomomichi Nakamura; Toru Masuzawa; Eisuke Tatsumi; Yoshiyuki Taenaka; Hisateru Takano, Three kinds of rechargeable batteries, NiCd, NiMH, and Li+, were compared for the purpose of selecting the most appropriate battery for use in a Rechargeable Internal Back-up Battery (RIBB) unit for a Totally Implantable Artificial Heart. Batteries of each kind were connected in series to obtain the required driving voltage of 24 V. The NiCd and NiMH batteries were charged by a constant current of 1 C, and the Li+ batteries were charged first by a constant current of 1 C and later by a constant voltage of 28.7 V. All three types of batteries were discharged using a dummy electronic pulsatile load consuming 20 W of power. The tests showed that the Li+ batteries were capable of supplying the required energy for more than 60 minutes. The Li+ batteries had a specific energy of 121.5 Wh/kg, which was more than 3× that of the NiCd and NiMH, and an energy density of 282.5 Wh/L more than double that of the other two. In addition, the Li+ batteries recorded the least temperature rise during charging and discharging. The results of our tests conclusively showed that the Li+ battery is the best among the three for use in an RIBB from the viewpoint of energy density and temperature rise., Lippincott-Raven Publ
ASAIO Journal, 1999年, [査読有り] - A transcutaneous energy transmission system with rechargeable internal back-up battery for a totally implantable total artificial heart
Kenji Shiba; Eimei Shu; Kohji Koshiji; Kinji Tsukahara; Tomomichi Nakamura; Toru Masuzawa; Eisuke Tatsumi; Yoshiyuki Taenaka; Hisateru Takano, We have been developing an externally coupled transcutaneous energy transmission system (ECTETS) for a totally implantable total artificial heart (TITAH). When the ECTETS is unable to supply the energy to drive the TITAH from outside the body, a rechargeable internal back-up battery (RIBB) implanted inside the body is used as a back-up to supply the required energy. This paper reports on the performance characteristics of our ECTETS with an RIBB. In this study, a lithium-ion (Li+) secondary battery was used as the RIBB. The transcutaneous energy transmission and the charging control characteristics of the ECTETS, while simultaneously supplying energy to the TITAH and the RIBB, were evaluated in an in vitro experiment. The output power and transmission efficiency of the ECTETS operating in this mode were found to vary from 20 W to 34 W and from 84% to 71%, respectively. It was also found that a sufficient power of more than 20 w could be supplied to the TITAH. The time needed to fully charge the RIBB was 117 minutes, and a fully charged RIBB could drive the TITAH, consuming 20 W for 62 minutes. It may, therefore, reasonably be concluded that the ECTETS with the RIBB is sufficient to drive the TITAH., Lippincott-Raven Publ
ASAIO Journal, 1999年, [査読有り] - Cardiac autonomic nervous function during long-term nonpulsatile left heart bypass
Tomohiro Nishinaka; Eisuke Tatsumi; Takashi Nishimura; Yoshiyuki Taenaka; Toru Masuzawa; Masako Nakata; Hisateru Takano; Hitoshi Koyanagi, We investigated the changes in cardiac autonomic nervous activities during long-term nonpulsatile left heart bypass (NLHB) by analyzing heart rate variability. A pulsatile ventricular assist device was installed in 3 goats, and pulsatile left heart bypass (PLHB) was conducted for 2 weeks. Then, NLHB was maintained for the following 4 weeks. The segmental data of the R-R intervals (R-Rs) was analyzed by maximum entropy spectral analysis. Changes in evaluated parameters from the last week of PLHB to the 4th week of NLHB were as follows: the mean R-Rs increased from 511 ms to 692 ms
the coefficient of variation of R-R increased from 10.2 to 14.1%
the power of the low frequency band (LF) increased from 747 ms2 to 2,855 ms2
the power of the high frequency band (HF) increased from 512 ms2 to 1,270 ms2
and the ratio of LF to HF increased from 2.6 to 6.5. These results indicated that the cardiac autonomic nervous activity, both sympathetic and parasympathetic, increased during long-term NLHB.
Artificial Organs, 1999年, [査読有り] - Augmentative effect of pulsatility on the wall shear stress in tube flow
Masako Nakata; Eisuke Tatsumi; Tomonori Tsukiya; Yoshiyuki Taenaka; Takashi Nishimura; Tomohiro Nishinaka; Hisateru Takano; Toru Masuzawa; Kenkichi Ohba, Wall shear stress (WSS) has been considered to play an important role in the physiological and metabolic functions of the vascular endothelial cells. We investigated the effects of the pulse rate and the maximum flow rate on the WSS to clarify the influence of pulsatility. Water was perfused in a 1/2 inch transparent straight cylinder with a nonpulsatile centrifugal pump and a pulsatile pneumatic ventricular assist device (VAD). In nonpulsatile flow (NF), the flow rate was changed 1 to 6 L/min by 1 L/min increments to obtain standard values of WSS at each flow rate. In pulsatile flow (PF), the pulse rate was controlled at 40, 60, and 80 bpm, and the maximum flow rate was varied from 3.3 to 12.0 L/min while the mean flow rate was kept at 3 L/min. The WSS was estimated from the velocity profile at measuring points using the laser illuminated fluorescence method. In NF, the WSS was 12.0 dyne/cm2 at 3 L/min and 33.0 dyne/cm2 at 6 L/min. In PF, the pulse rate change with the same mean, and the maximum flow rate did not affect WSS. On the other hand, the increase in the maximum flow rate at the constant mean flow rate of 3 L/min augmented the mean WSS from 13.1 to 32.9 dyne/cm2. We concluded that the maximum flow rate exerted a substantial augmentative effect on WSS, and the maximum flow rate was a dominant factor of pulsatility in this effect.
Artificial Organs, 1999年, [査読有り] - Diminished vasoconstrictive function caused by long-term nonpulsatile left heart bypass
Takashi Nishimura; Eisuke Tatsumi; Tomohiro Nishinaka; Yoshiyuki Taenaka; Toru Masuzawa; Masako Nakata; Hisateru Takano, We investigated the functional changes of the systemic vascular system due to prolonged nonpulsatile left heart bypass (NPLHB). Three adult goats underwent pulsatile left heart bypass (PLHB). Two weeks later the PLHB was changed to the NPLHB, which was conducted for 4 weeks. The aortic pulse pressure was 39 and 16 mm Hg during the PLHB and NPLHB, respectively. Systemic vascular resistance (SVR) and the plasma norepinephrine level were measured at the end of PLHB (PUL), and in the 1st, 2nd, 3rd, and 4th weeks of NPLHB (NP1w, NP2w, NP3w, and NP4w). At each point, 1 μg/kg norepinephrine was injected, and the elevation of the SVR (ΔSVR) was calculated. The SVR and the plasma norepinephrine level did not change significantly during the entire course. However, ΔSVR decreased during NPLHB and became significantly lower at NP3w and NP4w than that at PUL (NP3w: 839 ± 164, NP4w: 746 ± 268, and PUL: 1,239 ±324 dyne · s · cm-5). These results strongly indicated that prolonged NPLHB significantly diminished the constrictive function of the vascular system.
Artificial Organs, 1999年, [査読有り] - 覚醒下静動脈バイパスにおける循環動態と液性因子の変動-肺血流の段階的変化による定量的検討
武輪 能明; 巽 英介; 妙中 義之; 中谷 武嗣; 増澤 徹; 西村 隆; 中村 真人; 遠藤 誠子; 高野 久輝; 田中 操一, 静動脈バイパス(VAB)による心肺補助中に生じる肺動脈血流(PAF)の減少が循環動態に与える影響を解明するため, 成山羊6頭を用いたVABでPAFを段階的に変化させ, 血行動態の変動と肺で代謝される血管作動性物質の血中濃度変化について検討した. 平均大動脈圧(mAoP)と体血管抵抗(SVR)はPAFの減少に比例して有意に低下した. 血管拡張物質のprostaglandin E2(PGE2)とNOはPAFの減少に応じて増加し, prostacyclinはPAFが0%で著しく増加した. この中で, PGE2がSVRと最も強い相関を示した. 血管収縮物質では, renin-angiotensin系はPAFの減少に比例して増加し, mAoPと強い負の相関を示した. 一方, catecholamineとantidiuretic hormoneはPAFが0%でのみ著しく増加した. これら血管収縮物質の変化は血圧低下の二次的な反応と考えられた. 以上よりVAB中のPAF減少による血行動態の変動には肺で代謝される血管拡張物質が中心的役割を演じている可能性が示唆された., JAPANESE SOCIETY FOR ARTIFICIAL ORGANS
人工臓器, 1998年08月 - Prolonged nonpulsatile left heart bypass with reduced systemic pulse pressure causes morphological changes in the aortic wall
T Nishimura; E Tatsumi; S Takaichi; Y Taenaka; Y Wakisaka; T Nakatani; T Masuzawa; Y Takewa; M Nakamura; S Endo; M Nakata; H Takano, We investigated the morphological changes in the aorta due to reduced systemic pulse pressure in prolonged nonpulsatile left heart bypass (LHB). Nineteen adult goats were divided into 3 groups, the nonpulsatile group in which nonpulsatile LHB was conducted, the pulsatile group in which pulsatile LHB was conducted, and the control group used as the normal control. The average aortic pulse pressures were 12, 47, and 37 mm Hg, respectively. The descending aorta was subjected to morphological examination. In the nonpulsatile group, the wall was significantly thinner, and the volume ratio of smooth muscle cells (SMCs) was much lower. In terms of the SMC type classification, the proportion of SMCs with low activity and low contractility was higher, and the cell density of the SMCs was increased compared to those in the other groups. These results indicate that prolonged nonpulsatile LHB causes morphological atrophic changes in the aorta., BLACKWELL SCIENCE INC
ARTIFICIAL ORGANS, 1998年05月, [査読有り] - Development of design methods of a centrifugal blood pump with in vitro tests, flow visualization, and computational fluid dynamics: results in hemolysis tests.
Takiura K; Masuzawa T; Endo S; Wakisaka Y; Tatsumi E; Taenaka Y; Takano H; Yamane T; Nishida M; Asztalos B; Konishi Y; Miyazoe Y; Ito K., There are few established engineering guidelines aimed at reducing hemolysis for the design of centrifugal blood pumps. In this study, a fluid dynamic approach was applied to investigate hemolysis in centrifugal pumps. Three different strategies were integrated to examine the relationship between hemolysis and flow patterns. Hemolytic performances were evaluated in in vitro tests and compared with the flow patterns analyzed by flow visualization and computational fluid dynamic (CFD). Then our group tried to establish engineering guidelines to reduce hemolysis in the development of centrifugal blood pumps. The commercially available Nikkiso centrifugal blood pump (HPM-15) was used as a standard, and the dimensions of 2 types of gaps between the impeller and the casing, the axial and the radial gap, were varied. Four impellers with different vane outlet angles were also prepared and tested. Representative results of the hemolysis tests were as follows: The axial gaps of 0.5, 1.0, and 1.5 mm resulted in normalized index of hemolysis (NIH) values of 0.0028, 0.0013 and 0.0008 g/100 L, respectively. The radial gaps of 0.5 and 1.5 mm resulted in NIH values of 0.0012 and 0.0008 g/100 L, respectively. The backward type vane and the standard one resulted in NIH values of 0.0013 and 0.0002 g/100 L, respectively. These results revealed that small gaps led to more hemolysis and that the backward type vane caused more hemolysis, Therefore, the design parameters of centrifugal blood pumps could affect their hemolytic performances. In flow visualization tests, vortices around the impeller outer tip and tongue region were observed, and their patterns varied with the dimensions of the gaps. CFD analysis also predicted high shear stress consistent with the results of the hemolysis tests. Further investigation of the regional flow patterns is needed to discuss the cause of the hemolysis in centrifugal blood pumps., BLACKWELL SCIENCE INC
Artificial Organs, 1998年05月 - ヘパリン化処理人工肺の連続使用による性能評価-最長36日間の検討-
武輪 能明; 巽 英介; 妙中 義之; 中谷 武嗣; 増澤 徹; 西村 隆; 中村 真人; 遠藤 誠子; 高野 久輝; 田中 操一, ヘパリンコーティング人工肺の長期性能を慢性動物実験にて評価した. 成山羊6頭(体重50.0±1.1kg)を用い, 拍動型補助心臓を用いたV-Aバイパスに人工肺を組み込んだ. 抗凝血療法はヘパリンを2-3IU/kg/hr使用した. 評価期間は2-36日(17±14日)で, 血栓症を生じた1例を除いて人工肺に起因する中止原因はなかった. 期間中, 血流量3.7±0.6L/min, 酸素血流量比2.7±0.5の条件でガス交換能は, 酸素添加量173±39ml/min, 二酸化炭素除去量165±44ml/minと安定して推移した. 実験後の人工肺を観察したところ, 17日以上灌流した3例では入口側の血液室辺縁に血栓塊を認めたが, その他は微小な血栓を認めるのみであった. 凝固線溶系に大きな変動は見られず, 血小板数の減少も許容範囲内であった. 以上より開発したヘパリン化処理人工肺は, 抗凝血療法非施行下で, 安定したガス交換能および血液適合性を示しつつ最長36日の連続使用が可能であり, 長期間における有用性が示唆された., JAPANESE SOCIETY FOR ARTIFICIAL ORGANS
人工臓器, 1998年04月 - 完全埋込型人工心臓用体外結合型経皮エネルギー伝送システム ~電気工学的観点からのin vitroおよびin vivo評価~
柴 建次; 周 英明; 越地 耕二; 塚原 金二; 土本 勝也; 大海 武晴; 中村 知道; 遠藤 誠子; 増澤 徹; 巽 英介; 妙中 義之; 高野 久輝, DC-DCエネルギー伝送効率が86%以上の完全埋込型人工心臓駆動用体外結合形経皮エネルギー伝送システム(ECTETS)のin vitro及びin vivo実験を行った。体内コイル、体内整流回路をヤギ皮下に埋込み、体外に設置された(1)電子負荷装置または(2)電気油圧駆動方式完全埋込型人工心臓をECTETSにより動作させた。その結果、(1)において、DC-DCエネルギー伝送効率は、81.4%(出力電力19.2W)であった。In vitroと比べ効率が低下したのは、体外コイル滅菌のための消毒液の付着により分布静電容量が増加したことが原因であることがわかった。また、(2)人工心臓の駆動(70bpm)においては、駆動電力、拍出流量、DC-DCエネルギー伝送効率、埋込部最高温度はそれぞれ20.7W、6.2L/min、82.1%、40.4℃となり生体に影響がない程度であることが確認された。, JAPANESE SOCIETY FOR ARTIFICIAL ORGANS
日本人工臓器学会会誌 人工臓器, 1998年04月, [査読有り] - エレクトロハイドローリック方式全人工心臓の慢性動物実験による生体内評価
巽 英介; 増澤 徹,妙中義之,中村真人,遠藤誠子,西村 隆,孫 領相,大野 孝,瀧浦晃基,武輪能明,中谷武嗣,高野久輝, エレクトロハイドローリック方式全人工心臓を体重62kgの仔牛に埋込み、生体内での基本性能を10日間にわたって評価した。全身麻酔体外循環下に血液ポンプおよびアクチュエータを埋込み、85bpmの固定拍動数で駆動した。左右拍出量バランスをとるために心房中隔に径4.5mmのシャント孔を設けた。埋込み手技に困難はなかった。実験期間中血行動態は良好に維持され、心房間シャントにより安定した左右拍出バランスが得られた。全身酸素代謝も良好に維持され、主要臓器機能にも異常を認めなかった。装置からの熱発生も十分許容できる範囲にあった。術後9日目から駆動オイルの漏出を認め、術後10日目にベアリング破損を伴うアクチュエータ停止により実験を終了した。剖検所見では装置周辺組織の圧迫は軽微で、解剖学的適合性は良好であった。本検討により、システムの満足できる生体内での基本性能が確認され、また耐久性に関連する問題点が明らかとなった。, JAPANESE SOCIETY FOR ARTIFICIAL ORGANS
人工臓器, 1998年04月 - 可視化解析による全人工心臓用血液ポンプ室内流れの検討
中田雅子; 増澤 徹,巽 英介,瀧浦晃基,妙中義之,高野久輝,大場謙吉,土本勝也,塚原金二,大海武晴
人工臓器, 1998年04月 - 体内完全埋込型人工心臓に用いる経皮エネルギー伝送ユニットの生体適合性及び実用性の評価-体内埋込時の温度特性とエネルギー伝送効率の検討-
中村知道; 増澤 徹,遠藤誠子,角田幸秀,巽 英介,妙中義之,高野久輝,柴 建次,越地耕二, 体内完全埋込型全人工心臓用体外結合型経皮エネルギー伝送システム(TETS)の生体適合性を実用化の面からin vitro, in vivo実験にて評価した. in vitro実験では模擬負荷を用いて約24Wの電気エネルギーを伝送し, シリコン封入前後の整流回路の発熱分布特性をそれぞれ空気中で評価した. in vivo実験:では体重44kgの成山羊に体内(2次)コイルと整流回路を埋め込み, 模擬負荷を用い約24Wの電気エネルギーを伝送し, 整流回路の内部及び表面, 体外コイル表面の発熱, エネルギー伝送効率を評価した. また, エネルギー伝送中に時速2km/hのトレッドミル試験を行い, 体動によるエネルギー伝送効率への影響を検討した. その結果, 体内埋込型整流回路に異常な高温部は認められず, 生体組織に対して充分許容範囲内の発熱特性を示した. また, 伝送効率は実験条件によらず80~85%を維持した. 以上の点から, 開発中のTETSは充分な生体適合性および実用性を有することが確認された., JAPANESE SOCIETY FOR ARTIFICIAL ORGANS
人工臓器, 1998年04月 - 電気油圧式全人工心臓の放熱特性に関する検討
遠藤誠子; 増澤 徹,巽 英介,妙中義之,中谷武嗣,大野 孝,脇坂佳成,西村 隆,武輪能明,中村真人,瀧浦晃基,孫 領相,高野久輝
人工臓器, 1998年02月 - 完全置換型人工心臓装着後の循環血液量の変化と液性因子の検討
中村真人; 巽 英介,増澤 徹,大野 孝,妙中義之,瀧浦晃基,孫 領相,遠藤誠子,西村 隆,武輪能明,脇坂佳成,中谷武嗣,高野久輝, 全人工心臓(TAH)埋め込み後早期の循環血液量(CBV)とCBV調節に関係する液性因子の変動を、仔牛4頭を用いた慢性動物実験により検討した。正常対照1頭と電気油圧型または空気駆動型TAHの埋め込みを行った3頭を対象に、CBVとANP、ADH、血漿レニン活性、アンギオテンシン-I、IIを測定した。TAH埋め込み動物では術後4、8日目のCBVは、術前の111~155%へと増加していた。ANPはTAH装着による低下を示さず、ADHも1頭で術後2日目に一過性の上昇を認めた以外はほぼ正常範囲で経過し、ANPとADHの変化が直接CBVを増加させた可能性は低い。一方、TAHを埋め込んだ2頭においてレニン-アンギオテンシン系の亢進がみられ、CBV増加と関連していた可能性が示唆されたが、TAH埋め込みに共通した変化とはいえなかった。以上より、TAH装着後早期からCBVは増加するが、これらの因子が直接原因となっている可能性は低いと考えられた, JAPANESE SOCIETY FOR ARTIFICIAL ORGANS
人工臓器, 1998年02月 - 心房間シャントによる電気油圧駆動方式全人工心臓システムの左右心拍出量差代償に関する研究
巽 英介; 中村真人,増澤 徹,妙中義之,孫 領相,中田雅子,大野 孝,遠藤誠子,西村 隆,武輪能明,中谷武嗣,高野久輝, 電気油圧駆動方式全人工心臓(EHTAH)の心房間シャント(IAS)の左右差代償能力を評価した。閉鎖型模擬回路を用いたin vitro評価では、気管支動脈流量の増加に伴って心房間圧較差も増大し、その程度はサイズの小さいIASほど顕著であった。径4.4mm以上のIASでは5%までの気管支動脈血流において許容できる心房間圧較差であった。シャント流量波形上観察された右→左方向の逆流成分は、心嚢膜で形成した一方向弁を取り付けたIASではほぼ完全に消失した。慢性動物実験によるin vivo評価では、体重62kgの仔牛にEHTAHを埋込み、径4.5mmのIAS(弁なし)を形成して10日間駆動した。実験期間中の心房間圧較差は4±1mmHgで安定して推移し、広い範囲の心房圧に対して動的な左右差の代償を行い得た。剖検時にIASの内部や周辺に血栓形成を認めず、良好な開存状態を示した。以上より、IASはEHTAHシステムの左右差を代償するための基本的能力を有することが示された, JAPANESE SOCIETY FOR ARTIFICIAL ORGANS
人工臓器, 1998年02月 - In vitro and in vivo evaluation on heat dissipation of electrohydraulic total artificial heart
Seiko Endo; Toru Masuzawa; Eisuke Tatsumi; Yoshiyuki Taenaka; Takeshi Nakatani; Takasi Ohno; Yoshinari Wakisaka; Takashi Nishimura; Yoshiaki Takewa; Makoto Nakamura; Koki Takiura; Young Sang Sohn; Hisateru Takano, We evaluated the heat transfer characteristics of an electrohydraulic total artificial heart (EH-TAH) that have been developed at our institute. In two in vitro experiments, the heat dissipation way of the TAH was investigated. First, we simulated heat transfer of the calf circulation by using a heat exchanger. The amount of heat dissipating directly from the TAH surface and that to the blood chamber were estimated to be almost the same. Second, the temperature of the actuator examined with thermography was found to be almost uniform, and no prominent high temperature area was observed. In an in vivo study, the TAH was implanted in a calf weighing 62 kg for 10 days. The input power to the device was 18 ± 2 W, the temperature of the actuator- tissue contacting surface was 39-41 °C. This slight temperature elevation was thought to be attributable to the heat dissipation to the blood. Upon histological study of the chest wall and the lung in contact with the actuator, vascularized connective tissue enveloped were observed and unfavorable side effects such as tissue necrosis were not observed. These results suggest that the thermal effect of this system is acceptable at this input power.
Japanese Journal of Artificial Organs, 1998年 - Transcutaneous optical telemetry system with infrared laser diode
Katsushige Inoue; Kenji Shiba; Eimei Shu; Kohji Koshiji; Kinji Tsukahara; Takeharu Oh-Umi; Toru Masuzawa; Eisuke Tatsumi; Yoshiyuki Taenaka; Hisateru Takano, A transcutaneous telemetry system is indispensable when monitoring and controlling the operation of an artificial heart totally implanted inside the body. A telemetry system using light is more useful than radio waves from the viewpoint of electromagnetic interference and power consumption. In this report, a transcutaneous optical coupler consisting of an infrared laser diode (LD) and a PIN photodiode (PINPD) was evaluated, and the transcutaneous optical coupling and information transmission characteristics were evaluated in in vitro experiments. The wavelength and directional angle of the LD used were 830 nm and 9.5 degrees, respectively. With regard to the directional angle of PINPD, the authors found that a PINPD with a larger directional angle allowed for more deviation between the axes optical axes of the LD and the PINPD. It was also found that the transcutaneous coupler had an optimum distance for the permissible deviation to be maximized. The information signals modulated by the phase shift keying (PSK) were transmitted at a rate of 9,600 bps through goat skin 4 mm thick, and demodulated by the phase locked loop (PLL) on the receiving side. As a result, the information signals were demodulated without any errors in deviation within 10.5 mm at a distance of 11 mm. In conclusion, the transcutaneous optical telemetry system using an infrared LD has sufficient characteristics to monitor and control the operation of an artificial heart totally implanted inside the body., Lippincott-Raven Publ
ASAIO Journal, 1998年, [査読有り] - Characterization and optimization of the flow pattern inside a diaphragm blood pump based on flow visualization techniques
Masako Nakata; Toru Masuzawa; Eisuke Tatsumi; Yoshiyuki Taenaka; Takashi Nishimura; Tomonori Tsukiya; Hisateru Takano; Katsuya Tsuchimoto; Kenkichi Ohba, We applied two different flow visualization techniques to obtain detailed information on the inside flow of the diaphragm blood pump of our electrohydraulic total artificial heart system to determine the optimum washout effect that would result in better antithrombogenicity. Major orifice directions of the inflow and outflow Bjork-Shiley valves of the left blood pump were independently changed to create 17 varied patterns. The character and velocity of the main flow at the diaphragm-housing junction were acquired using a laser light sheet method with polyethylene tracers. Wall shear flow, a major factor governing washout in the blood pump, was estimated by a newly developed paint erosion method. In this method, quantitative evaluation for an index of washout effect was made by calculating the residual ratio of the paint on the blood pump inner surface at 30 sec of pumping. When a single circular flow was consistently observed by the laser light sheet method, the paint residual ratio become low, indicating washout was relatively good. At the lowest paint residual ratio, the center of the circular flow observed by the laser light sheet method was located at the geometric center of the blood chamber. In conclusion, the flow pattern inside the blood pump could be characterized by combined use of these two flow visualization techniques, and the significant role of circular flow in better washout was clarified., Lippincott-Raven Publ
ASAIO Journal, 1998年, [査読有り] - Development of a flow estimation and control system of an implantable centrifugal blood pump for, circulatory assist
Yoshinari Wakisaka; Yasuki Okuzono; Yoshiyuki Taenaka; Kenichi Chikanari; Seiko Endo; Toru Masuzawa; Hisateru Takano, A bypass flow rate estimation and control system (BECS) for an implantable centrifugal blood pump (ICBP) has been developed in our institute. The estimated flow rate (EF) of the ICBP was derived from the electric power consumption, the rotating speed of a motor, and the blood viscosity presumed by the hematocrit and body temperature. The error in the EF was 0.5 ± 0.4 L/min in vivo experiments for 40 days. The rotating speed of the motor was controlled automatically every 200 ms to bring the EF in accord with the desired flow rate (DF). The reactivity and accuracy of the BECS were investigated in vitro and in vivo experiments. The ICBP was operated by the BECS in a mock circuit in parallel with a pulsatile ventricular assist device (PVAD) to simulate left heart bypass. The reactivity was evaluated by changing the DF from 7 L/min to 5 L/min at an afterload of 160/97 mm Hg. To evaluate the accuracy of the BECS, the ICBP was driven under the aortic pressure of 110/85 mm Hg in the abdominal wall of an adult goat (70 kg). The DF was set at 5 L/min for 4 min for the goat in an awake condition. It took 13 s to change the flow rate in the in vitro experiment. The measured flow rate (MF) was maintained at 5.0 ± 0.2 L/min by the BECS in vivo. In conclusion, the BECS has moderate reactivity and accuracy.
Artificial Organs, 1998年, [査読有り] - 遠心血液ポンプのインペラ端・ケーシング間間隙の溶血性能への影響(共著)
増澤 徹; 築谷 朋典; 遠藤 誠子; 巽 英介; 妙中 義之; 山根 隆志; 西田 正浩; アスタロシュ バラージュ; 宮副 雄貴; 伊藤 和之; 澤入 利夫; 小西 義昭, The purpose of this study is to examine the relationship between the flow condition and hemolysis level by integrating hemolysis test, flow visualization and computational fluid dynamics(CFD)to establish design criteria for the good hemocompatible centrifugal pump. Axial and radial gaps between the impeller tip and casing wall of Nikkiso centrifugal blood pump were modified independently and flow condition and hemolytic property of these pumps were examined. Examined gaps were 1.5, 1.0, and 0.5 mm for axial gap and 3.0, 2.0, 1.0, and 0.5 mm for radial gap, respectively. The pumps with the axial gap of 0.5 mm and the radial gap of 0.5 mm showed higher hemolysis level than the other pumps showed. Maximum shear stress in the pump, estimated by CFD, were increased by decreasing the radial gap from 3.0 to 0.5 mm. Regional flow pattern change at the tongue region by decreasing radial gap was observed by flow visualization. Gaps between impeller tip and casing wall are dominant factors to determine hemolytic property of the centrifugal pump. Relationship between regional flow pattern and blood trauma should be investigated in the future., The Society of Life Support Engineering
ライフサポート, 1998年 - In vitro and in vivo heat dissipation of an electrohydraulic totally implantable artificial heart
S Endo; T Masuzawa; E Tatsumi; Y Taenaka; T Nakatani; T Ohno; Y Wakisaka; T Nishimura; Y Takewa; M Nakamura; K Takiura; YS Sohn; H Takano, The authors evaluated the heat transfer characteristics of an electrohydraulic totally implantable artificial heart (EH-TAH) developed at our institute. In three in vitro experiments, the heat dissipation of the EH-TAH was investigated. First, the EH-TAH was connected to a closed mock circuit filled with 1 L of saline, and driven at an input power of 20 W. The estimated heat conducted to the blood was similar to 10.3 W, which was almost half of the input power. Second, we simulated heat transfer with the circulation of a calf by using a heat exchanger. The amount of heat dissipating directly from the EH-TAH surface was calculated to be 10 W. Third, the temperature of the actuator examined with thermography was found to be almost uniform, and no prominent high temperature area was observed. In an in vivo study, the EH-TAH was implanted for 10 days in a calf weighing 62 kg. The input power was 18 +/- 2 W, the temperature of the actuator-tissue contacting surface was 39.5 +/- 0.8 degrees C, and that of the pump blood chamber was 39.8 +/- 0.4 degrees C. This slight temperature elevation was thought to be attributable to heat dissipation to the blood. On histologic study of the chest wall and the lung in contact with the actuator, vascularized connective tissue envelopes were observed, but unfavorable side effects, such as tissue necrosis, were not observed. These results suggest that the thermal effect of this system is acceptable at the input power used., LIPPINCOTT-RAVEN PUBL
ASAIO JOURNAL, 1997年09月, [査読有り] - Establishment of flow estimation for an implantable centrifugal blood pump
Yoshinari Wakisaka; Yasuki Okuzono; Yoshiyuki Taenaka; Kenichi Chikanari; Toru Masuzawa; Hisateru Takano, A less invasive and non thrombogenic flow estimation of an implantable centrifugal blood pump (ICBP) has been developed, which was derived from electric power consumption, the rotating speed of a motor, and blood viscosity presumed by hematocrit and body temperature. The power consumption and the rotating speed of the motor were measured by a wattmeter every 0.2 sec. Accuracy and stability of the estimated flow (EF) were investigated during in vitro and in vivo experiments. The EF was compared with a measured flow rate (MF) monitored by an electromagnetic flowmeter. During in vitro experiments, the EF and MF were measured at 79 operating points. The ICBP was driven in a closed mock loop filled with goat blood with hematocrit values of 21.5, 28, 34, and 42%. During in vivo experiments, the ICBP was implanted in the chest cavity of a goat and driven for 40 days with continuous estimation of the bypass flow rate. Blood was taken to determine hematocrit value several times a week. The temperature of the pleura away from the ICBP was measured every 15 min. A linear correlation between the EF and MF was observed, and the correlation coefficient between the EF and MF was 0.99 during in vitro examinations. An averaged error of the EF was 0.5 L/min, with the MF ranging from 2.3 to 8.1 L/min during in vivo experiments. In conclusion, flow estimation was established with good stability and accuracy in both in vitro and in vivo experiments., Lippincott-Raven Publ
ASAIO Journal, 1997年09月, [査読有り] - Hemodynamic and humoral conditions in stepwise reduction of pulmonary blood flow during venoarterial bypass in awake goats
Yoshiaki Takewa; Eisuke Tatsumi; Yoshiyuki Taenaka; Kazuhiro Eya; Takeshi Nakatani; Takashi Nishimura; Young-Sang Sohn; Toru Masuzawa; Yoshinari Wakisaka; Makoto Nakamura; Seiko Endo; Hisateru Takano; Soichiro Kitamura, The effects of reduced pulmonary arterial blood flow (PAF) during venoarterial bypass (VAB) on hemodynamic and humoral conditions were investigated in a series of experiments in a chronic animal model. A biventricular bypass system was installed in five adult goats weighing 49.8 ± 1.1 kg. Two weeks later, the extracorporeal circuitry was changed to VAB without anesthesia. The PAF was reduced stepwise from 100% to 50, 25, 10, and 0% of total systemic flow. The mean aortic pressure and systemic vascular resistance decreased from 110 ± 14 to 66 ± 3 mmHg and from 1,288 ± 77 to 740 ± 73 dyne · sec/cm5, respectively, in proportion to the decrease in PAF from 100 to 0%. The prostaglandin E2 concentration increased from 1.5 ± 0.6 to 8.8 ± 0.6 pg/ml following the decrease in PAF from 100 to 0%. The renin-angiotensin system increased in proportion to the decrease in PAF. In contrast, the epinephrine and norepinephrine concentrations (60 ± 10 and 227 ± 80 pg/ml, respectively, at 100% PAF) did not change appreciably even at 10% PAF, but were markedly elevated to 335 ± 117 and 2,088 ± 1,503 pg/ml at 0% PAF. The antidiuretic hormone level similarly changed. In conclusion, decrease in PAF during VAB exerts significant effects on hemodynamics in a proportional manner and on vasoactive humoral factors in a diverse manner., Lippincott-Raven Publ
ASAIO Journal, 1997年09月, [査読有り] - Morphologic changes of the aortic wall due to reduced systemic pulse pressure in prolonged non pulsatile left heart bypass
Takashi Nishimura; Eisuke Tatsumi; Shigeko Takaichi; Yoshiyuki Taenaka; Yoshinari Wakisaka; Takeshi Nakatani; Toru Masuzawa; Yoshiaki Takewa; Makoto Nakamura; Seiko Endo; Young-Sang Sohn; Hisateru Takano, The morphologic changes of the aortic wall due to reduced systemic pulse pressure in prolonged non pulsatile left heart bypass (LHB) were investigated. Sixteen adult goats were divided into three groups: the non pulsatile group in which non pulsatile LHB was conducted for 137 days on average, the pulsatile group in which pulsatile LHB was conducted for 79 days on average, and the control group used as the normal control. The average aortic pulse pressures were 12, 48, and 37 mmHg, respectively. At the end of the experiments, the descending aorta was excised and subjected to morphologic examination. The wall thickness of the aorta in the non pulsatile group (1.4 mm) was significantly thinner than that in the pulsatile group (2.2 mm) and the control group (2.0 mm), and the volume ratio of smooth muscle cells (SMC) in the non pulsatile group (37%) was lower than that in the pulsatile group (48%) and the control group (49%). In SMC classification, the proportion of SMC with low activity and low contractility in the non pulsatile group (57%) was high as compared with that in the pulsatile (2%) and control (5%) groups. These results strongly indicate that prolonged non pulsatile LHB causes substantial morphologic changes in the aorta., Lippincott-Raven Publ
ASAIO Journal, 1997年09月, [査読有り] - In vitro and in vivo evaluation of a left-right balancing capacity of an interatrial shunt in an electrohydraulic total artificial heart system
Tatsumi E; Nakamura M; Masuzawa T; Taenaka Y; Sohn YS; Nishimura T; Nakata M; Nakatani T; Ohno T; Endo S; Takiura K; Takewa Y; Kakuta Y; Takano H, The authors evaluated the basic performance of an interatrial shunt (IAS) made by punching a hole in the atrial septum, in accommodating the left-right imbalance in our electrohydraulic total artificial heart (EHTAH) system. In an in vitro study conducted in a closed mock circuit connected with the EHTAH, the interatrial pressure gradient changed in compliance with the amount of bronchial flow and the size of the IAS. The IAS of 4.4 mm diameter or larger maintained the interatrial pressure gradient within physiologically permissible limits when the amount of bronchial flow was 5% of cardiac output or less. A left-to-right one-way valve made of a piece of pericardium, a possible option in this IAS method, successfully prevented right-to-left reverse shunt flow through the IAS. In a chronic in vivo study using a calf implanted with the EHTAH for 10 days, a 4.5 mm IAS without the one-way valve demonstrated satisfactory dynamic left-right balancing capacity with a stable interatrial pressure gradient of 4 +/- 1 mmHg over a wide range of atrial pressures. No thrombus was found in or around the IAS at autopsy. The authors conclude that the IAS is a simple and promising means of left-right balancing in the EHTAH system., LIPPINCOTT-RAVEN PUBL
ASAIO Journal, 1997年09月 - Characteristics of mixed venous oxygen saturation and physical activity as parameters for artificial heart control
Ohno T; Masuzawa T; Nakamura M; Tatsumi E; Taenaka Y; Nakatani T; Wakisaka Y; Nishimura T; Takewa Y; Takano H; Fukui Y, Mixed venous oxygen saturation (SvO(2)) and physical activity (PhyAc) are practical candidates as parameters of total artificial heart (TAH) control because SvO(2) can be measured through a transparent blood pump housing with infrared rays and PhyAc can be calculated from signals of an accelerometer used for rate response pacemakers. Although the methods for measurement of the parameters have already been developed, characteristics of these parameters for TAH control, such as during exercise, are still unclear and were examined in this study. SvO(2), cardiac output (CO), and PhyAc were measured as parameters. Multi-stage treadmill exercise tests were performed. Difference values (DVs) from the value at the start of exercise showed better correlation than did absolute values. Correlation coefficients between DV in CO and DV in SvO(2) and between DV in CO and PhyAc were high at -0.82 and 0.72, while the time constants for the change of SvO(2) and CO to the PhyAc change were 26 and 32 sec. Although the correlation coefficient between the CO and SvO(2) was higher than that between CO and PhyAc, PhyAc responded more quickly to the speed change compared with the response of SvO(2) and CO. It was concluded that SvO(2) and PhyAc were useful parameters with different characteristics for TAH control during exercise., LIPPINCOTT-RAVEN PUBL
ASAIO Journal, 1997年09月 - 長期心肺補助を目的にした一体型心肺補助装置の開発
武輪 能明; 巽 英介; 赤城 治彦; 江屋 一洋; 妙中 義之; 中谷 武嗣; 増澤 徹; 脇坂 佳成; 西村 隆; 大野 孝; 瀧浦 晃基; 中村 真人; 遠藤 誠子; 孫 領相; 高野 久輝; 依田 巧; 岡本 健彦; 大原 康次郎; 田中 操一, 人工肺と血液ポンプを一体化した長期間使用可能な新しい心肺補助装置を開発し, 動物実験にて性能を評価した. 本装置は人工肺部分の両側を2つのプッシャープレート型血液ポンプではさむ構造を有し, 血流鬱滞を解消することで抗血栓性の向上を計った. また, 人工肺部分には血漿漏出のない特殊ポリオレフィン膜(膜面積1.5m2)を使用し, 血液接触面にはヘパリンの共有結合処理を施した. in vitro試験では, 最大拍出量7L/min, 圧損失約10mmHg/L/minのポンプ特性を示した. 成山羊2頭を用いた完全VAバイパスの急性実験では, 血流量5L/minにて, 酸素運搬量300ml/min, 炭酸ガス除去量250ml/minのガス交換能を示し, 6時間安定して呼吸循環を代行し得た. また, 他の成山羊2頭を用いた右心バイパスの慢性実験では, 抗凝血薬非投与下に7日間の駆動が可能で, 良好な抗血栓性を示した. 以上より本装置の長期心肺補助装置としての有用性が示唆された., JAPANESE SOCIETY FOR ARTIFICIAL ORGANS
人工臓器, 1997年04月 - 人工肺(2)
小林 絋一; 武輪 能明; 巽 英介; 妙中 義之; 中谷 武嗣; 増澤 徹; 西村 隆; 中村 真人; 遠藤 誠子; 高野 久輝; 田中 操一; 猪狩 次雄; 星野 俊一; 岩谷 文夫; 引地 仁; 土本 勝也; 磯山 隆; 中村 真之; 田原 耕一郎; 桑名 克之; 森 康真; 川上 浩良; 長岡 昭二; 窪田 倭; 金森 敏幸; 新保 登志夫, JAPANESE SOCIETY FOR ARTIFICIAL ORGANS
人工臓器, 1997年 - Long-term evaluation of a nonpulsatile mechanical circulatory support system
Yoshinari Wakisaka; Yoshiyuki Taenaka; Kenichi Chikanari; Takeshi Nakatani; Eisuke Tatsumi; Toru Masuzawa; Takashi Nishimura; Yoshiaki Takewa; Takashi Ohno; Hisateru Takano, Antithrombogenicity of a centrifugal pump (CP) developed in our institute is provided by a central balancing hole (BH) in the impeller. A current CP, the National Cardiovascular Center (NCVC)-2, was ameliorated to improve antithrombogenicity, whereby the BH diameter was widened to improve self washout flow velocity, and an edge of the thrust bearing was rounded off to minimize flow separation. Effects of these modifications were assessed in a long-term in vivo experiment. The antithrombogenicity, hemolytic property, and mechanical durability of the NCVC-2 were investigated in 3 goats. The NCVC-2 was installed paracorporeally between the left atrium and the aorta and driven as long as possible at rotating speeds of about 2,800 rpm. The NCVC-2 ran for 50, 200, and 367+ days. The mean bypass flow rates were 6,8, 5.0, and 5.3 L/min, respectively. Creatinine, blood urea nitrogen (BUN), glutamic-oxaloacetic transaminase (GOT), and glutamic-pyruvic transaminase (GPT) did not increase until one week before termination. Plasma free hemoglobin was kept to a level less than 15 mg/dl, except for the last week of the second case. These results indicate that the NCVC-2 has excellent antithrombogenicity, an acceptable hemolytic property and the necessary durability for prolonged use., Blackwell Publishing Inc.
Artificial Organs, 1997年, [査読有り] - Impact of systemic depulsation on tissue perfusion and sympathetic nerve activity
Koichi Toda; Eisuke Tatsumi; Yoshiyuki Taenaka; Toru Masuzawa; Hisateru Takano, Background. We postulated that pathophysiologic processes under nonpulsatile circulation are related to the behavior of the sympathetic nerve activity that regulates tissue perfusion. Methods. Pulsatile and nonpulsatile pumps were installed in parallel in the left heart bypass circuit of anesthetized goats (n = 9) so that pulsatile circulation could be converted to nonpulsatile circulation instantly. At 5 minutes before and after systemic depulsation, we measured hemodynamic indices, renal nerve activity, and regional blood flow of the brain, heart, and renal cortex. Results. Renal nerve activity was significantly elevated after systemic depulsation (15.6 ± 9.3 versus 19.4 ± 9.8 μV), when mean aortic pressure remained almost constant. The renal cortical flow was significantly reduced after depulsation (3.61 ± 1.23 versus 2.93 ± 1.19 mL · min-1 · g-1), whereas no significant difference was found in the regional blood flow of the brain or the heart. Conclusions. The significant reduction of renal cortical blood flow after systemic depulsation is associated with a significant increase in renal nerve activity. Our results suggest that increased renal nerve activity plays an important role in the reduction of renal function after systemic depulsation.
Annals of Thoracic Surgery, 1996年12月, [査読有り] - Development of a precise controller for an electrohydraulic total artificial heart improvement of the motor's dynamic response
Ahn JM.Masuzawa T. Taenaka Y. Tatsumi E. Ohno T. Choi WW. Toda K. Miyazaki K. Baba Y. Nakatani T. Takano H. Min BG., In an electrohydraulic total artificial heart developed at the National Cardiovascular Center (Osaka, Japan), two blood pumps are pushed alternatively by means of the bidirectional motion of a brushless DC motor for pump systole and diastole. Improvement in the dynamic response of the motor is very important to obtain better pump performance; this was accomplished by using power electronic simulation. For the motor to have the desired dynamic response, it must be commutated properly and the damping ratio (zeta), which represents transient characteristics of the motor, must lie between 0.4 and 0.8. Consequently, all satisfactory specifications with respect to power consumption must be obtained. Based on the simulated results, the design criteria were determined and the precise controller designed to reduce torque ripple and motor vibration, and determine motor stop time at every direction change. In in vitro tests, evaluation of the controller and dynamic response of the motor was justified in terms of zeta, power consumption, and motor stop time. The results indicated that the power consumption of the controller and the input power of the motor were decreased by 1.2 and 2.5 W at zeta = 0.6, respectively, compared to the previous system. An acceptable dynamic response of the motor, necessary for the reduction of torque ripple and motor vibration, was obtained between zeta = 0.5 and zeta = 0.7, with an increase in system efficiency from 10% to 12%. The motor stop time required for stable motor reoperation was determined to be over 10 msec, for a savings in power consumption of approximately 1.5 W. Therefore, the improved dynamic response of the motor can contribute to the stability and reliability of the pump., LIPPINCOTT-RAVEN PUBL
ASAIO Journal, 1996年09月 - Tandem operation of a turbo blood pump (BP-80-type centrifugal pump) to reduce hemolysis
Wakisaka Y; Taenaka Y; Nakatani T; Anai H; Araki K; Nishimura T; Tatsumi E; Masuzawa T; Baba Y; Toda K; Eya K; Miyazaki K; Takewa Y; Takano H, When operating turbo blood pumps in tandem, the strength of shear stress is reduced, but the exposure duration of the stress is increased. The purpose of this experiment was to compare the degree of contribution of these two factors on hemolysis as well as to evaluate the effectiveness of the tandem operation of turbo blood pumps. Tandem operation of two Bio-pumps (BP-80; Medtronics Bio-medicus, Inc., Eden Prairie, Minnesota, U.S.A,) were compared with single operation of a BP-80 in in vitro hemolysis tests in three different driving conditions, that is, pumping heads of 200, 350, and 500 mm Hg under a pump flow rate of 5 L/min. The Alien's hemolytic indexes of the tandem operation at pumping heads of 200, 350, and 500 mm Kg were 0.014, 0.020, and 0.080 mg/dl, respectively. The hemolytic indexes of the single operation at pumping heads of 200, 350, and 500 mm Hg were 0.014, 0.056, and 0.12 mg/dl, respectively. These results indicate that tandem operation is a useful method of reducing hemolysis with the BP-80 under high pumping heads and that the effect on hemolysis of exposure to higher shear stresses may be more serious than that of longer durations of exposure to shear stress in, Artificial Organs
Artificial Organs, 1996年08月 - Sympathetic nerve activities in pulsatile and nonpulsatile systemic circulation in anesthetized goats
Koichi Toda; Eisuke Tatsumi; Yoshiyuki Taenaka; Toru Masuzawa; Hisateru Takano, To investigate the effects of pulsatile and nonpulsatile systemic circulation on the sympathetic nerve activity, using a left heart bypass technique, we converted systemic circulation between the pulsatile and the nonpulsatile mode in anesthetized goats and analyzed differences in periodicity and quantity of renal nerve activity (RNA). After pulsatile systemic circulation was converted to the nonpulsatile mode, the mean RNA was significantly increased from 10.7 ± 3.6 to 13.1 ± 3.4 μV and periodic discharges of RNA, which corresponded to pulse-related rhythm during pulsatile circulation, became obscure, whereas an 8-12 cycle/s rhythm, which was distinguished and accounted for 30 ± 9% of total intervals during pulsatile circulation, became dominant (48 ± 11%). These results clarified a significant increase in mean RNA after depulsation of the systemic circulation and indicated that the cardiac related rhythm in RNA could be produced by periodic inputs from arterial baroceptors alone, whereas the 8- 12 cycle/s rhythm that was present regardless of the type of circulation was the fundamental rhythm originating from the vasomotor center.
American Journal of Physiology - Heart and Circulatory Physiology, 1996年07月, [査読有り] - Development of a centrifugal pump with improved antithrombogenicity and hemolytic property for chronic circulatory support
Taenaka Y; Wakisaka Y. Masuzawa T. Tatsumi E. Toda K. Miyazaki K. Eya K. Baba Y. Nakatani T. Ohno T. Nishimura T. Takano H., A centrifugal pump with a unique structure has been developed for chronic support. The pump is driven by a magnetic coupling and has no rotating shaft, no seal around the rotating part, and a balancing hole at the center of the impeller and the thrust bearing. The pump was improved in stepwise fashion to realize good antithrombogenicity and low hemolysis. The first pump, the National Cardiovascular Center (NCVC)-0, had an impeller with 4 rectangular and curved vanes; 6 triangularly shaped curved vanes were employed in the second model, the NCVC-1, to reduce trauma to the blood. In the third design, the NCVC-2, the central hole was enlarged, and the thrust bearing shoulder was rounded so that blood washing was enhanced around the impeller; stream lines also were smoothed for improved antithrombogenicity. The hemolytic property of the device was evaluated in vitro with heparinized fresh goat blood; hemolysis indexes of the NCVC-0, -1, and -2 were 0.05, 0.01, and 0.006 g per 100 L, respectively. Antithrombogenicity of the pumps was examined in animal experiments as a left heart bypass device in goats weighing 52-75 kg. Six NCVC-0 pumps were driven for 14 to 33 (22.0 +/- 7.6) days in goats receiving the antiplatelet drug cilostazol orally. Four NCVC-1 pumps ran for 1 to 80 (28.5 +/- 30.6) days with the same drug regimen in 2 cases and with no anticoagulation therapy in 2 cases. After 3 preliminary 1-week tests of NCVC-2 pumps in animals, the pump was installed in 3 goats; 2 pumps were still running on the 182nd and 58th pumping day. Intracorporeal implantation also was attempted successfully. The results indicate that this pump has promising features for chronic support although longer term and additional evaluations are necessary., BLACKWELL SCIENCE INC
Artificial Organs, 1996年06月 - Influence of non pulsatile systemic circulation on tissue blood flow and oxygen metabolism
Eisuke Tatsumi; Koji Miyazaki; Koichi Toda; Yoshiyuki Taenaka; Takeshi Nakatani; Yuzo Baba; Toru Masuzawa; Yoshinari Wakisaka; Kazuhiro Eya; Takashi Nishimura; Yoshiaki Takewa; Takashi Ohno; Hisateru Takano, Influence of non pulsatile systemic circulation on oxygen metabolism was examined regarding tissue perfusion in 12 adult goats weighing from 46 to 55 kg. Under general anesthesia, a flow character, changeable total left heart bypass circuit consisting of pulsatile and non pulsatile pumps was installed through a left thoracotomy. Systemic flow was converted from pulsatile to non pulsatile in 7 of 12 animals, and in the reverse order in the other 5, by changing the driving pump. Esophageal mucosal blood flow was determined by a colored microsphere method that estimated tissue blood flow at the pre capillary level. Esophageal intramucosal pH was evaluated with a silicone balloon tonometer catheter surgically placed in the submucosal space. Hemodynamic and arterial blood gas parameters were unchanged at flow mode conversion. Although oxygen delivery was comparable between pulsatile and non pulsatile circulation, oxygen extraction ratio was lower and venous oxygen saturation was higher in non pulsatile than pulsatile circulation. Although statistically not significant, serum lactate level tended to be higher with non pulsatile circulation. No difference was observed in esophageal mucosal blood flow between pulsatile and non pulsatile circulation, whereas intramucosal pH, which strongly correlated with arterial pH regardless of the flow mode, was significantly lower under non pulsatile than pulsatile conditions. In conclusion, systemic oxygen uptake is less efficient in non pulsatile than pulsatile circulation in the setting of an acute experiment using animals, which may be accounted for by the disparity between the pre capillary blood flow and actual tissue oxygen metabolism., Lippincott Williams and Wilkins
ASAIO Journal, 1996年 - Altered oxygen metabolic conditions associated with increased norepinephrine levels in a nonpulsatile systemic circulation
Eisuke Tatsumi; Koji Miyazaki; Koichi Toda; Yoshiyuki Taenaka; Takeshi Nakatani; Yuzo Baba; Toru Masuzawa; Kazuhiro Eya; Yoshinari Wakisaka; Takashi Nishimura; Yoshiaki Takewa; Takashi Ohno; Hisateru Takano, Change in oxygen metabolic conditions accompanying the conversion of systemic flow from pulsatile to nonpulsatile (from P-mode to N-mode) was investigated in association with blood norepinephrine levels. Total left heart bypass was instituted through a left thoracotomy under general anesthesia in 10 adult goats. Pulsatile and nonpulsatile pumps were incorporated in the circuit in parallel, and the flow character was rapidly converted from the P-mode to the N-mode. Norepinephrine levels increased significantly after the conversion, from 222 ± 54 pg/ml to 285 ± 65 pg/ml. While oxygen delivery (DO2) was kept constant, the oxygen extraction ratio significantly decreased, from 21 ± 3% to 16 ± 3%, and venous oxygen saturation (SvO2) significantly increased, from 77 ± 6% to 84 ± 6% after depulsation. The serum lactate level was significantly higher in the N-mode than the P-mode (P-mode: 35 ± 2 mg/dl, N-mode: 45 ± 5 mg/dl). Strong positive and negative correlations of norepinephrine levels were observed with oxygen extraction ratio and SvO2, respectively, whereas norepinephrine levels did not correlate with DO2. Regression lines in these correlations unveiled higher oxygen uptake in the P-mode than the N-mode at the same norepinephrine level. These results indicate that, in the setting of an acute animal experiment, oxygen uptake is less efficient with the absence of pulsatility, and the higher norepinephrine concentration functioned to tune the oxygen metabolism in the initial stage of nonpulsatile systemic circulation., Lippincott Williams and Wilkins
ASAIO Journal, 1996年 - Development of an integrated artificial heart-lung device for long-term cardiopulmonary support
Eisuke Tatsumi; Yoshiaki Takewa; Haruhiko Akagi; Yoshiyuki Taenaka; Kazuhiro Eya; Takeshi Nakatani; Yuzo Baba; Toru Masuzawa; Yoshinari Wakisaka; Koichi Toda; Koji Miyazaki; Takashi Nishimura; Takashi Ohno; Hisateru Takano, An integrated artificial heart-lung device has been developed as a long- term cardiopulmonary support system. The device is composed of gas exchange and pumping units. The gas exchange unit consists of a special hollow fiber membrane that can prevent serum leakage. The entire blood contacting surface of the gas exchange unit is treated with covalent heparin bonding. The pumping unit consists of two pusher-plate artificial hearts joined to each end of the artificial lung unit. The core size and priming volume of the device are 11 x 14 x 17 cm and 400 ml, respectively. In in vitro evaluation, the device exhibited a maximum output of 7.0 L/min, with a pressure gradient of 10 mmHg per 1 L/min flow rate. In acute in vivo evaluation with adult goats, the device satisfactorily replaced the animals' circulation and respiration for 6 hr. Pumping output ranged from 5.5 to 6.0 L/min, whereas PaO2 and PaCO2 were kept above 500 mmHg and below 30 mmHg, respectively. The device demonstrated prominent thrombus resistant properties in nonheparin animal use trials. These results indicate that the integrated artificial heart-lung device has a potential to be a long-term cardiopulmonary support system that can be used with minimal anticoagulant therapy., Lippincott Williams and Wilkins
ASAIO Journal, 1996年 - Evaluation of a two stage axial flow pump on hemolysis
Wakisaka Y; Anai H; Nakatani T; Araki K; Taenaka Y; Tatsumi E; Masuzawa T; Baba Y; Toda K; Eya K; Takano H, To reduce hemolysis in an axial flow pump (AP), a basic study of a two stage AP (2S) was performed. The 2S was evaluated in two kinds of in vitro hemolysis tests for four hours. In this first test, the 2S was compared with two kinds of single stage (APs (ISs). Each pump was designed to be operated at a flow rate of 5 l/min and a pressure head of 100 mmHg. The 2S was series operation of two single stage APs designed at a flow rate of 5 λ/min and a pressure head of 50 mmHg. One of the ISs has the same specific speed (Ns) of the 2S and the other IS has the same impeller of the single stage of the 2S. In the second test, hemolysis in each stage of the 2S was evaluated. The basic structure of all single stage APs were same. Allen's hemolytic index (III) of the 2S, that was regarded as an aggregate III of both stage AP, was less than those of the ISs. These data suggests that the 2S was useful to reduce hemolysis in an AP., Japanese Journal of Artificial Organs
Japanese Journal of Artificial Organs, 1996年01月 - Set-up, improvement, and evaluation of an electrohydraulic total artificial heart with a separately placed energy converter
T Masuzawa; Y Taenaka; E Tatsumi; JM Ahn; T Ohno; K Toda; K Miyazaki; Y Wakisaka; K Eya; Y Baba; T Nakatani; H Takano; C Uyama; K Koshiji; Y Fukui; K Takahashi; K Tsuchimoto; K Tsukahara, The authors have been developing an electrohydraulic total artificial heart (TAH) system with a separately placed electrohydraulic energy converter to minimize anatomic constraints in the pericardial space. Improvements to the system and current status of the development are reported. The energy converter was miniaturized to improve implantability, and its thickness was reduced to 54 mm. System efficiency was increased by suppressing rush current at the time of motor reversal. Maximum cardiac output of the TAH system was 9 L/min, and maximum system efficiency increased to 10%. The blood pump system was implanted easily in the body of a 57 kg calf, and no significant temperature rise on the energy converter surface was observed. As the next step, main components were integrated into a total system. The transcutaneous energy transfer system could supply power to the TAH without a decline in pump performance, and the internal battery could support the system at 6.5 L/min of cardiac output for 1 hour without a decrease in cardiac output. The authors consider the TAH system with a separately placed energy converter the most promising approach to development of a TAH for smaller sized patients., LIPPINCOTT-RAVEN PUBL
ASAIO Journal, 1996年 - Hemolysis and heart generation in six different types of centrifugal blood pumps
Araki K; Taenaka Y; Masuzawa T; Tatsumi E; Wakisaka Y; Watari M; Nakatani T; Akagi H; Baba Y; Anai H; Park YH; Eya K; Toda K; Takano H, What the most causative factor affecting hemolysis is still controversial. To resolve this problem, we investigated the relationship between hemolysis and heat generation in six types of centrifugal blood pumps (Bio-Pump, Delphin, Capiox, Nikkiso, Isoflow, and Toyobo). The analyzed parameters were index of hemolysis in fresh goat blood, pumping performance, and heat generation in a thermally isolated mock circuit. These parameters were analyzed at a flow rate of 5 L/min by changing the pressure head (100 mm Hg and 500 mm Hg). At 500 mm Hg of pressure head, the Bio-Pump needed the highest rotation number and showed the highest hemolytic rate and heat generation. The index of hemolysis is well correlated to heat generation (r(2) = 0.721). Heat may originate from the motor by conduction, hydraulic energy loss, and mechanical friction between the shaft and seal. We strongly suspect that hemolysis was caused by a factor such as mechanical friction which generates heat locally., BLACKWELL SCIENCE PUBL INC CAMBRIDGE
Artificial Organs, 1995年09月 - Heat generation and hemolysis at the shaft seal in centrifugal blood pumps
Araki K; Taenaka Y; Wakisaka Y; Masuzawa T; Tatsumi E; Nakatani T; Baba Y; Eya K; Toda K; Takano H; Koga Y; Yagura A, The heat and hemolysis around a shaft seal were investigated. Materials were original pumps (Nikkiso HMS-15:N-original, and 3M Delphin:D-original), vane-removed pumps (Nvane(-), Dvane(-)), and a small chamber with a shaft coiled by nichrome wire (mock pump). The original pumps were driven at 500 mmHg and 5 L/min, and vane-removed pumps were driven at the same rotation number. An electrical power of 0, 0.5, 2, and 10 W was supplied to the mock pumps. In vitro hemolytic testing showed that hemolytic indices were 0.027 g/100 L in N-original, 0.013 in Nvane(-), 0.061 in D-original, and 0.012 in Dvane(-). Measurement of heat with a thermally insulated water chamber showed total heat within the pump of 8.62 and 10.85 W, and heat at the shaft seal of 0.87 and 0.62 W in the Nikkiso and Delphin pumps, respectively. Hemolysis and heat generation of mock pumps remained low. The results indicate that the heat generated around the shaft seal was minimal. Hemolysis at the shaft-seal was considerable but not major. Local heat did not affect hemolysis. It was concluded that the shaft-seal affected hemolysis, not by local heat but friction itself., ASAIO Journal
ASAIO Journal, 1995年01月 - Improvement in antithrombogenicity in a centrifugal pump with self wash-out structure for long-term use
Wakisaka Y; Taenaka Y; Tatsumi E; Araki K; Masuzawa T; Nakatani T; Baba Y; Anai H; Eya K; Toda K; Takano H, Antithrombogenicity in the initial (NCVC-1) centrifugal pump (CP) developed at our institute is provided by a central balancing hole in an impeller that promotes self wash-out blood flow (Sf) around the impeller. The current CP (NCVC-2) was ameliorated to obtain better antithrombogenicity, where the balancing hole diameter was widened to improve Sf velocity (Vsf), and the edge of a thrust bearing (TB) was rounded to minimize flow separation. Effects of the modifications were assessed in in vitro and in vivo studies. The Vsf of the NCVC-1 and the NCVC-2 evaluated by Doppler velocimeter were 12.8 and 22.1 cm/sec, respectively. Flow around the TB visualized by a light cutting method confirmed less flow stagnation in the NCVC-2. In vivo antithrombogenicity of the CPs was investigated in three goats. A pulsatile VAD (P-VAD) was installed paracorporeally between the left atrium and the aorta. After 3 weeks, the P-VAD was exchanged for the NCVC-2 and the NCVC-1 in sequence. Each CP was driven for 1 week and disassembled. No anticoagulation was used, except for heparin injection at pump exchange. Thrombus at the TB was found in the two NCVC-1s, and two little thrombi were on the impeller o, ASAIO Journal
ASAIO Journal, 1995年01月 - Experimental evaluation of intravenous axial flow pump for right heart assist
Nakatani T; Anar H; Wakisaka Y; Araki K; Taenaka Y; Tatsumi E; Akagi H; Masuzawa T; Baba Y; Eya K; Toda K; Tominaga M; Choi W; Kitoh Y; Takano H, We have developed intravenous axial flow pump for right heart assist. In this study, experimental evaluation of this system was performed. The pump was positioned in the right heart through a 14 mm, low porosity graft anastomosed to the infrarenal inferior vena cava. The pump showed good performance in right heart assistance under induced pulmonary stenosis or induced biventricular failure. Chronic animal experiments were performed using adult goats. There was no difficulties in pump insertion. Level of plasma hemoglobin was acceptable. There was not prominent damages in heart tissues. In conclusion, this pump system is practicable for temporary right heart assist., Japanese Journal of Artificial Organs
Japanese Journal of Artificial Organs, 1995年01月 - Development of an intravenous axial flow pump for temporary right heart assist
Nakatani T; Anai H; Wakisaka Y; Taenaka Y; Tatsumi E; Masuzawa T; Baba Y; Eya K; Toda K; Araki K; Takano H, In clinical settings, quick application systems with easy access for circulatory support are desired. For left heart assist, an intraarterial axial flow pump (Hemopump) has been developed and applied to clinical cases. However, no simple way has been proposed for right heart assist. We have developed an intravenous axial flow pump for temporary right heart assist and have reported its hemodynamic effect. In this study, in vivo evaluation of this system was performed. The pump system consists of an outflow cannula, an impeller that was newly developed for intravenous use, and a driving system for the Hemopump. A prototype pump demonstrated 3.2 L/min of maximal flow at a pressure differential against 40 mmHg at a pump speed of 28,000 rpm in mock circulation. Application to goats is as follows. A 14 mm low porosity graft was anastomosed to the infrarenal inferior vena cava (IVC). The pump system was inserted into the IVC through the graft and advanced to the right heart using balloon catheter guidance under fluoroscopy, and the tip of the cannula of the pump was positioned at the main pulmonary artery. In acute experiments, this system provided effective right heart assist under induc, ASAIO Journal
ASAIO Journal, 1995年01月 - Approach to decrease hemolysis caused by axial blood flow pump
Anai H; Araki K; Nakatani T; Wakisaka Y; Taenaka Y; Tatsumi E; Akagi H; Masuzawa T; Baba Y; Eya K; Toda K; Takano H, To decrease hemolysis caused by an axial flow blood pump, we studied whether specific speed at the design point should be kept within the existing engineering standard range or whether pump speed should be reduced to a minimum. Four pumps were designed at a flow of 5 L/min, a head of 100 mmHg and speeds of 14000-26000 rpm. Specific speed of each pump was calculated as 758-1407 (m, m 3 /min, rpm). Hemolytic tests were performed with flesh goat blood in a mock circuit. The lowest level of hemolysis is observed in the pump with the minimum specific speed (758) that is out of the existing engineering standard range. We also studied the influence of change in design of guide vanes on hemolysis. Four guide vanes that had different length and number of vanes were devised for same impellers. In the result of hemolysis test, difference in hemolytic index was not clearly observed among the pumps that had different guide vanes., Japanese Journal of Artificial Organs
Japanese Journal of Artificial Organs, 1995年01月 - Heat generation and hemolysis in centrifugal blood pumps
Araki K; Taenaka Y; Masuzawa T; Wakisaka Y; Nakatani T; Akagi H; Baba Y; Anai H; Eya K; Toda K; Takano H, We investigated the effect of heat and friction around a shaft-sealing on hemolysis in centrifugal blood pumps. The materials were original pumps (Nikkiso HMS-15 and 3M Delphin), vane-removed pumps and a small chamber with a shaft coiled by a nichrome wire (mock pump) to investigate the effect of local heat on hemolysis. In-vitro hemolytic examination was carried out using heparinized fresh blood of a goat. The original pumps were driven at the flow rate of 5 L/min and pressure head of 500 mmHg. The vane-removed pumps were driven at the same rotation number and the flow of 5 L/min was maintained by Bio-pumps (1000 rpm). Electric power of 0, 0.5, 2 and 10 Watts was supplied to the mock pump and the flow was maintained in the same way. We also measured generated heat of the original pumps and vane-removed pumps with a thermally-insulated water chamber. The results indicated that the heat generated around the shaft-sealing was minimal. The hemolysis of the shaft- sealing was, however, considerable but not principal. The local heat less than 10 Watts did not affect hemolysis. We concluded that a shaft-sealing affects hemolysis by not local heat but the friction, and the main causative, Japanese Journal of Artificial Organs
Japanese Journal of Artificial Organs, 1995年01月 - Development of an electrohydraulic total artificial heart at the National Cardiovascular Center, Osaka, Japan
Masuzawa T.Taenaka Y. Tatsumi E. Choi W. Toda K. Baba Y. Nakatani T. Takano H. Uyama C. Koshiji K. Fukui Y. Ohno T. Takahashi K., The authors have been developing an electrohydraulic total artificial heart with a basic concept placing the blood pumps and an electrohydraulic energy converter separately, in the thorax and the abdominal region, respectively, to minimize anatomic constraints. Major problems of the system were a high energy consumption of 56 W at 6 L/min output and an insufficient maximum output of 6.7 L/min. The energy converter was redesigned to overcome these problems. A three phase, 4 pole brushless DC motor, which has maximum efficiency of 79% at a motor rotation of 2500 rpm with a load of 0.1 Nm, was developed for the new energy converter. Flow-channel design of the regenerative oil pump was optimized, which resulted in increasing the maximum flow rate at one directional motor rotation from 18 to 29 L/min. In vitro performance of the electrohydraulic total artificial heart was evaluated in a mock circulation with physiologic pressure conditions. Maximum output was increased to 10.7 L/min at a pump rate of 120 bpm and energy consumption of the motor at 6 L/min output was reduced to 18 W. Based upon these favorable results, the system is now being assembled for chronic animal implantation., LIPPINCOTT-RAVEN PUBL
ASAIO Journal, 1995年 - 体内完全埋込式全人工心臓の開発(共著)
増澤 徹; 妙中 義之; 巽 英介; 中谷 武嗣; 赤城 治彦; 高野 久輝; 越地 耕二; 大野 孝; 福井 康裕; 高橋 克己; 笹川 広志; 塚原 金二; 土本 勝也; 大海 武晴, 臨床応用可能な体内埋込型全人工心臓の実現を図るために、エレクトロハイドローリック方式全人工心臓の油圧アクチュエータの改良を行った。負荷トルク1kg・cm、回転数2500rpmにおいて効率79%の人工心臓専用ブラシレスDCモータを開発し、入力電力の減少を図り、摩擦ポンプの流路の最適化を行うことにより一方向回転時送油能を従来の18L/minから28L/minに増大せしめ、後負荷100mmHg、前負荷10mmHgにて最大拍出流量10.7L/minの全人工心臓を実現した。左右心の流量バランス調節方法の一つとして、二重ダイアフラム方式血液ポンプを考案し、プロトタイプにて、その基礎的性能を確認した。今後は、摩擦ポンプのより一層のポンプ効率向上を図るとともに、本全人工心臓を用いた長期慢性動物実験を開始する予定である。, JAPANESE SOCIETY FOR ARTIFICIAL ORGANS
人工臓器, 1995年 - The animal experiments of total artificial heart at the national cardiovascular center in japan
HY Park; Tatsumi E. Masuzawa T. Taenaka Y. Anai H. Wakisaka Y. Eya K. Toda K. Baba Y. Akagi H. Araki K. Nakatani T. Takano H.
Korean J Thoracic Cardiovas Surg, 1994年10月 - In vitro and in vivo assessment of an intravenous axial flow pump for right heart assist
Nakatani T; Anai H; Araki K; Wakisaka Y; Taenaka Y; Tatsumi E; Akagi H; Masuzawa T; Baba Y; Eya K; Toda K; Takano H, Right ventricular (RV) function is a limiting factor in maintaining systemic circulation with circulatory assist. There is, however, no easy way to institute RV assist, such as the intraarterial axial flow pump (Hemopump) used for left heart assist. In this study, the feasibility and hemodynamic effect of intravenous use of an axial flow pump was examined. A pump system was developed with an outflow cannula and an impeller that were newly designed for intravenous insertion with a Hemopump driving system. The pump system characteristics using goat blood at a hematocrit of 26% indicated that maximum flow at a pressure differential against 40 mmHg is 3.2 l/min at a pump speed of 28,000 rpm. The pump was tested in adult goats by intravenous insertion through a 14 mm, low porosity graft anastomosed to the infrarenal inferior vena cava. The pump was advanced until the tip of the cannula was positioned at the main pulmonary artery, using balloon catheter guidance under fluoroscopy. RV assistance was evaluated by pressure tracing, and aortic flow (AF) measured by electromagnetic flowmeter under 1) induced pulmonary stenosis (PS), and 2) electrically induced ventricular fibrillation (VF) in, ASAIO Journal
ASAIO Journal, 1994年07月 - Development and evaluation of components for a totally implantable artificial heart system
Taenaka Y; Masuzawa T. Tatsumi E. Anai H. Toda K. Akagi H. Nakatani T. Baba Y. Eya K. Wakisaka Y. Takano H. Koshiji K. Shu E. Utsunomiya T. Fukui Y., The authors have been developing an electrohydraulic (EH) artificial heart system for total implantation. This system consists of intrathoracic ventricles, an abdominally placed EH actuator, flexible silicone oil conduits, externally coupled transcutaneous energy transfer (TET) system, transcutaneous optical telemetry (TOT) system, internal battery, and internal control drive unit. Fitting was evaluated in chronic animal experiments as a pneumatic system in 11 goats weighing 55.2 ± 4.2 kg and 3 calves of 52.3 ± 1.2 kg. The longest survival time in calves was 111 days, and that in goats was 51 days. The assembled EH pump was implanted in two goats of 49 and 50 kg as an acute experiment, and 4.2-6.7 L/min of cardiac output was maintained. For the TET system, an internal coil 3 cm in diameter was implanted to make an arch covered by skin. Electric energy was transmitted from the external to the internal coil, and energy of about 20 W was carried through wires to an external load. The DC-to-DC efficiency of the system was 76-83% for 40 days. The TOT system with internal light emitting diodes and external photodiodes also was evaluated in a goat. Disalignment of up to 12 mm was tolerated. Although more improvement is necessary, most of the components showed characteristics desirable for a totally implantable system., J.B. Lippincott Co
ASAIO Journal, 1994年07月 - 遠心ポンプにおけるin-vitro 性能評価
荒木賢二; 妙中義之.増澤 徹.脇坂佳成.中谷武嗣.赤城治彦.馬場雄造.松尾義昭.榊 雅之.穴井博文.渡 正伸.Young Hwan Park. 高野久輝
人工臓器, 1994年06月 - A Flow Visualization Study of the NCVC Centrifugal Blood Pump
Kenji Araki; Yoshiyuki Taenaka; Toru Masuzawa; Eisuke Tatsumi; Yoshinari Wakisaka; Masanobu Watari; Takeshi Nakatani; Haruhiko Akagi; Yuzo Baba; Hirofumi Anai; Young Hwan Park; Kazuhiro Eya; Koichi Toda; Hisateru Takano, Abstract: A compact centrifugal pump, NCVC–1, has an open–type impeller with 6 curved vanes, and it is characterized by no shaft and no seal. A tunnel is placed in the center of the impeller–rotor assembly to irrigate the back space behind the rotor. To evaluate the flow, we performed 3 visualization methods: tracer, oil film, and injection streak line method. The flow, observed by the tracer method in NCVC–1, indicated little turbulence along vanes. A volute chamber proved effective to reduce vortex formation in the outlet. Oil film pattern revealed no flow separation on vanes at 5 L/min. Washout flow behind the rotor is essential to prevent thrombus formation and was shown as inward spiral flow without any stagnation. These data suggested that a combination of visualization techniques was useful to analyze various flow conditions, and the NCVC–1 has excellent flow characteristics with little turbulence and little flow stagnation, which must be beneficial to low hemolysis and high antithrombogenicity. © 1994 International Society for Artificial Organs
Artificial Organs, 1994年, [査読有り] - Power of an in-situ latissimus dorsi muscle as an actuator for circulatory assistance
Araki K; Nakatani T; Toda K; Sakaki M; Taenaka Y; Masuzawa T; Akagi H; Baba Y; Matsuo Y; Anai H; Watari M; Park Y, We evaluated the effect of dissecting site and preconditioning which may influence the power generated by an in-situ latissimus dorsi muscle (LDM). To evaluate dissecting sites, 3 un-preconditioned adult goats underwent dissection of the origin of one site and the insertion of the other site. The other 3 adult goats which underwent 10 week-preconditioning were dissected their insertion of LDMs. By contracting muscles under various load, tension-length relationships in end-contraction and end-relaxation and their regression lines were obtained, and the maximum area of a square drawn within both regression lines was assumed to be maximum external work (maxW) of a LDM. The mean maxW generated by the origin-dissected and insertion-dissected LDMs was 0.432 J and 0.732 J, respectively. The power of three preconditioned LDMs changed 0.175 to 0.109 Watts (15 minute-stimulation), 0.137 to 0.094 Watts (60 minutes) and 1.17 to 0.037 Watts (60 minutes) from the beginning to the end of stimulations, respectively. We concluded that the tension-length relationship was useful for evaluation of the generated power of LDMs, and insertion-dissected LDMs could generate higher power than origin-dissect, Japanese Journal of Artificial Organs
Japanese Journal of Artificial Organs, 1994年01月 - Development of full-fill to full-empty drive control system of artificial hearts by measuring electrical impedance in a blood chamber with automatic trigger level adjustment method for ejecting phase
Anai H; Nakatani A; Sasaki E; Taenaka Y; Akagi H; Masuzawa T; Baba Y; Araki K; Inoue K; Sakaki M; Matsuo Y; Watari M; Park Y; Takano H, Continuous monitoring method of pump performance by measuring electrical impedance in a blood chamber was applied to the trigger system of full-fill to full-empty(F/E) drive control. An automatic trigger level adjustment method(ATAM) for settlement of a trigger level to change a phase from ejecting to filling was developed to maintain a definite stroke volume against changes of afterload or driving pressure. ATAM was an automatic searching algorism that can identify the volume change of last ejection by impedance method and settle next trigger level to maintain a destination stroke volume. In a mock circuit and animal experiments, ATAM functioned satisfactorily to follow the changes of afterload and driving pressure and maintained definite stroke volume. In conclusion, this method was practical and useful in regulation of F/E driving., Japanese Journal of Artificial Organs
Japanese Journal of Artificial Organs, 1994年01月 - An implantable left ventricular assist system with an electrical impedance monitoring and control system
Nakatani T; Anai H; Taenaka Y; Akagi H; Masuzawa T; Baba Y; Sakaki M; Araki K; Inoue K; Matsuo Y; Takano H, The authors developed an implantable left ventricular assist system (LVAS) for bridge to transplant of rather small sized adults. The pump was made of segmented polyether polyurethane and was 86 mm in diameter, 50 mm in height, with a 70 ml nominal stroke volume. A percutaneous drive line was connected with an external pneumatic control drive unit (CDU). In chronic animal experiments using 11 adult goats, the pump was installed between the LV apex and the descending aorta and was placed in the abdominal wall. Five goats were killed after 4 to 14 weeks while in good physical condition, and one is ongoing. There were no prominent thromboembolic symptoms despite no anti- thrombogenic agent being used. The new electrical impedance-based monitoring and control system (Z system) was installed in the CDU. In this Z system, automatic calibration was performed periodically for several seconds while the drive condition was changed to ensure full-fill of the blood pump. The full-fill to full-empty drive was well controlled by this Z system. In conclusion, the new Z system is practical and useful for monitoring and control of an implantable pump, giving this LVAS a promising place in clinical, ASAIO Journal
ASAIO Journal, 1993年10月 - 長期使用可能な人工心臓用遠心ポンプの開発-溶血減少のためのインペラ形状変更とその効果-
荒木賢二; 妙中義之; 増澤 徹; 井上和重; 中谷武嗣; 木下正之; 赤城治彦; 馬場雄造; 松尾義昭; 榊 雅之; 穴井博文; 高野久輝, 将来の遠心ポンプによる完全埋め込み型VADやTAHを目指して、長期使用可能な人工心臓用遠心ポンプの開発を行なっている。前モデルであるNCVC-0型はノンシール構造で、血流うっ滞部低減により、耐久性、抗血栓性に優れている。今回、溶血減少のためインペラデザインを変更し、NCVC-1型とした。すなわち、インペラ側面形状、羽根枚数、羽根入口角を平坦型、4枚、30度から山型、6枚、60度に変更した。その結果、in vitro試験にて、駆出能は揚程100mmHg、流量5L/minでの回転数がNCVC-0型2850rpm、NCVC-1型2450rpmであり、新鮮山羊血を用いた溶血係数は、NCVC-0型0.039g/100L、NCVC-1型0.011g/100Lであった。以上より、インペラ形状変更によりポンプ駆出能の向上、溶血減少が得られ、従来からの特徴である優れた耐久性、抗血栓性とも合わせて、長期の循環補助用として有望なポンプと考えられた。, JAPANESE SOCIETY FOR ARTIFICIAL ORGANS
人工臓器, 1993年06月 - 体内完全埋込型を目指したエレクトロハイドローリック式全人工心臓の急性動物実験による性能評価
妙中義之; 木下正之; 増澤 徹; 中谷武嗣; 赤城治彦; 榊 雅之; 松尾義昭; 井上和重; 馬場雄造; 穴井博文; 荒木賢二; 高野久輝; 藤田 毅, 重症心不全患者の救命と社会復帰のための体内完全埋込型人工心臓システムの主要部となる, エレクトロハイドローリック式全人工心臓の生体内性能を急性動物実験で評価した. この人工心臓では, 胸腔内の血液ポンプを腹壁などの胸腔外の体内に埋めたアクチュエータとしての摩擦ポンプで駆動する. アクチュエータと血液ポンプは曲げ延ばしが可能なステンレス製チューブで結合し, シリコンオイルを駆動媒体としている. 人工心臓を体重50kgと49kgの成山羊2頭に装着して駆動した. なお, 左右の心拍出量差を代償するために心房中隔に欠損孔を設けた. 人工心臓の装着手技は空気圧駆動式のものと同様に容易で, また, 血行動態はほぼ正常範囲に維持された. 本人工心臓は, 装着手技の容易さ, バランスを含めた左右心房圧や充分な心拍出量の維持, などの優れた生体内性能を示し, 体内完全埋込型システムの主要部として適切であると考えられた., JAPANESE SOCIETY FOR ARTIFICIAL ORGANS
人工臓器, 1993年06月 - A flow visualization study of centrifugal blood pumps developed for long-term usage
Araki K.Taenaka Y. Masuzawa T. Inoue K. Nakatani T. Kinoshita M. Akagi H. Baba Y. Matsuo Y. Sakaki M. Anai H. Takano H., We have developed centrifugal pumps for long-term circulatory assistance, with the final goal of a completely implantable ventricular assist device or total artificial heart. The previous model, NCVC-0, was characterized by a nonseal design and few flow-stagnating parts and acquired high durability and antithrombogenicity. To improve its pumping performance, NCVC-0 was modified. In the new model, NCVC-1, the profile shape of the impeller was changed from flat to conical, the number of vanes from 4 to 6, and the vane entrance angle from 30-degrees to 60-degrees. A flow visualization study performed by means of a combination of the polystyrene tracer method and the light-cutting method indicated decreased flow turbulence between vanes in NCVC-1, which corresponded well with the increased pumping performance. Flow visualization is a useful method to evaluate the design elements that are closely related to the pumping performance of a centrifugal blood pump., BLACKWELL SCIENCE INC
Artificial Organs, 1993年05月 - Diastolic mechanics of a skeletal muscle pump system actuated by in-situ bilateral latissimus dorsi muscles
Araki K; Nakatani T; Sakaki M; Matsuo Y; Taenaka Y; Kinoshita M; Masuzawa T; Akagi H; Baba Y; Inoue K; Anai H; Takano H, Japanese Journal of Artificial Organs
Japanese Journal of Artificial Organs, 1993年01月 - In vivo performance of an electrohydraulic total artificial heart toward the development of a totally implantable system
Taenaka Y; Kinoshita M; Masuzawa T; Nakatani T; Akagi H; Sakaki M; Matsuo Y; Inoue K; Baba Y; Anai H; Araki K; Takano H; Fujita T, Japanese Journal of Artificial Organs
Japanese Journal of Artificial Organs, 1993年 - The development of a centrifugal blood pump for a long-term usage - Modifications of the impeller and its effect on the hemolytic property
Araki K; Taenaka Y; Masuzawa T; Inoue K; Nakatani T; Kinoshita M; Akagi H; Baba Y; Matsuo Y; Sakaki M; Anai H; Takano H, Japanese Journal of Artificial Organs
Japanese Journal of Artificial Organs, 1993年01月 - Development of continuous monitoring and control system of artificial heart by measuring electrical impedance in a blood chamber with automatic calibration mechanism
Anai H; Nakatani T; Sasaki E; Taenaka Y; Kinoshita M; Akagi H; Masuzawa T; Baba Y; Sakaki M; Inoue K; Matsuo Y; Araki K; Takano H, Japanese Journal of Artificial Organs
Japanese Journal of Artificial Organs, 1993年01月 - A new ventilator system for liquid breathing driven by a linear motor
Baba Y; Taenaka Y; Tsukahara K; Akagi H; Nakatani T; Kinoshita M; Masuzawa T; Sakaki M; Inoue K; Matsuo Y; Anai H; Araki K; Ohumi T; Takano H, Japanese Journal of Artificial Organs
Japanese Journal of Artificial Organs, 1993年01月 - ニューラルネットワークによる循環動態調節機構のモデル化(共著)
増澤 徹; 木下 正之; 妙中 義之; 中谷 武嗣; 赤城 治彦; 高野 久輝, ニューラルネットワーク(NN)を用いた循環系のモデル化を行い、その基本的有用性の検討を行った。正常成山羊を用いてトレッドミル運動負荷時の生体信号収集を行い、そのデータを基に、血圧等より心拍出量を推定するモデルをNNを用いて構築した。NNの構造は、入力層42個、中間層32個、出力層10個の3層構造とし、入力信号として心拍数、動脈圧、静脈酸素飽和度、身体活動度を、出力信号として心拍出量を選択し、546セットの収集データを用いて600回のバックプロパゲーション法による繰返し学習を行い、心拍出量推定モデルを構築した。構築したNNに学習に用いた一部のデータ(70セット)および非学習データ(66セット)を入力し、計測心拍出量と推定心拍出量の相関を調べたところ、学習データでは相関係数0.965(p<0.001)、非学習データでは相関係数0.869(p<0.001)を得、本方式の基本的有用性を確認した。, JAPANESE SOCIETY FOR ARTIFICIAL ORGANS
人工臓器, 1993年 - A bioartificial ventricle used as a totally implantable circulatory assist device
Takeshi Nakatani; Akio Kishida; Takehisa Matsuda; Masayuki Sakaki; Masahiro Goto; Yoshiyuki Taenaka; Masayuki Kinoshita; Haruhiko Akagi; Toru Masuzawa; Yuzo Baba; Kenji Araki; Kazushige Inoue; Hirohumi Anai; Yoshiaki Matsuo; Hisateru Takano, The authors designed a totally implantable circulatory assist device consisting of a bioartificial ventricle composed of a skeletal muscle ventricle lined with a bioartificial endocardium. The bioartificial endocardium consists of a structural matrix made of a polyurethane porous membrane, fragmented blood vessels, and collagen gel. The authors prepared the polyurethane porous membrane by solvent cocasting with salt powder. They used collagen gel with fragmented goat carotid vein to perform in vitro construction of the bioartificial endocardium. For in vivo construction of the bioartificial endocardium, the authors used a modified version of the tissue fragment method for vascular prostheses. The authors prepared suspensions of tissue fragments using collagen gel with fragmented goat carotid artery. They used a highly porous fabric vascular prosthesis as a structural matrix
tissue fragments were entrapped on the outer surface of the prosthesis, and the prosthesis then was implanted into the carotid artery of four adult goats. In specimens 1 and 3 months postimplantation, cells from the fragmented tissue regenerated an endothelium-like monolayer sheet on the inner surface of the prostheses. Output of a prototype bioartificial ventricle reached 660 ml/min at an afterload of 60 mmHg and a preload of 20 mmHg. Based on these data, the authors conclude that the bioartificial ventricle is promising as an implantable device with excellent antithrombogenicity.
Trans Am Soc Artif Intern Organs, 1992年07月 - Pulmonary function in a non-pulsatile pulmonary circulation
Masayuki Sakaki; Yoshiyuki Taenaka; Eisuke Tatsumi; Takeshi Nakatani; Masayuki Kinoshita; Haruhiko Akagi; Toru Masuzawa; Yoshiaki Matsuo; Kazushige Inoue; Yuzo Baba; Hirohumi Anai; Kenji Araki; Hisateru Takano Tsutomu Kasugai, The authors suggested that a mammal immediately accommodates well to nonpulsatile flow in the systemic circulation. In the current study, nonpulsatile pulmonary blood flow using a centrifugal pump was established in chronic models to analyze its influence on the pulmonary circulation. A pulsatile right ventricular assist device (RVAD) was implanted to draw blood from both the right atrium and ventricle and send blood to the pulmonary artery in six goats. After 2 weeks, the pulsatile pump was quickly replaced with a centrifugal pump without anesthesia, and a 100% non-pulsatile pulmonary blood flow was obtained. Cardiac output was kept at 80-120 ml/kg/min during the experiments. No changes were observed in hemodynamic ters, including pulmonary arterial pressure, pulmonary vascular resistance index, and blood gas data, after the immediate depulsation of the pulmonary blood flow. There was also no significant change in the ventral to dorsal tissue blood flow ratio of the lower lobe of the right lung, which was calculated by a colored microsphere method, between pulsatile and non-pulsatile pulmonary blood perfusion. These results suggest that pulmonary function, including blood flow distribution, is not affected by non-pulsatile pulmonary circulation for periods up to 14 days.
Trans Am Soc Artif Intern Organs, 1992年07月 - Permeation of silicone oil through a diaphragm in an electrohydraulic ventricular assist system
Yoshiaki Matsuo; Yoshiyuki Taenaka; Hisateru Takano; Takeshi Nakatani; Toru Masuzawa; Haruhiko Akagi; Masayuki Kinoshita; Yuzo Baba; Masayuki Sakaki; Takeharu Ohumi; Kinji Tsukahara; Katsuya Tsuchimoto; Tetsuzo Akutsu, This study was designed to investigate the permeation of silicone oil through a pump diaphragm made of Pellethane in the authors' electrohydraulic ventricular assist system (EHVAS) and to evaluate influences on organ function. The permeability of the diaphragm to silicone oil was investigated by in vitro experiments. Influences on organ function were evaluated in five goats with an EHVAS by monitoring serum silicon levels (SSi), blood chemical parameters, and histologic findings. Elevation of silicone oil levels in Pellethane sheets immersed in silicone oil demonstrated that the Pellethane diaphragm was, in fact, permeable to silicone oil. The permeation rate of silicone oil was calculated to be 1.75 ml/year in the authors' EHVAS from the data of a diffusion apparatus test. Serum silicon levels did not increase during the EHVAS pumping, and renal and hepatic function were not affected. No abnormality or deposit suggestive of silicone oil was observed. However, the problem of permeation of silicone oil through the pump diaphragm must be solved to allow for a circulatory assist device for long-term use.
Trans Am Soc Artif Intern Organs, 1992年07月 - Influence of an impeller centrifugal pump on blood components in chronic animal experiments
Yoshiyuki Taenaka; Kazushige Inoue; Toru Masuzawa; Kenji Araki; Masayuki Sakaki; Yoshiaki Matsuo; Haruhiko Akagi; Takeshi Nakatani; Masayuki Kinoshita; Yuzo Baba; Hirifumi Anai; Hisateru Takano, A chronic animal experiment was designed to examine the changes in blood components induced by the use of a centrifugal pump (CP). In the pump, an impeller spins in a blood chamber by magnetic coupling with a rotating magnet outside the blood chamber. A pulsatile ventricular assist device was implanted between the left atrium and the descending aorta in four goats weighing from 63 to 75 kg
the CP was installed to replace the assist device, without surgery and anesthesia, more than 2 weeks later when the influences of implantation surgery were diminished. Antithrombotic therapy was performed with oral administration of an antiplatelet agent, cilostazol, a cyclic adenosine monophosphate phosphodiesterase at a dose of 30 mg/kg/day. No significant differences were observed in any of the following parameters: 1) hematocrit, 2) plasma free hemoglobin, 3) lactic acid dehydrogenase, 4) adenosine diphosphate, 5) platelet count, 6) fibrinogen, and 7) antithrombin III, between the data before and after the use of the CP, nor were deformation or pseudopods of platelets seen. The CP developed in the authors' institute and evaluated in this study did not damage blood components, and it proved to be a promising device for long-term use.
Trans Am Soc Artif Intern Organs, 1992年07月 - 小型多機能補助循環駆動装置の開発
中谷武嗣、佐々木栄作、穴井博文、妙中義之、木下正之、巽英介、増澤徹、赤城治彦、後藤昌弘、松尾義昭、榊雅之、井上和重、馬場雄造、高野久輝、近城賢一、橋本浩一、池田稔, VAS及びIABPの駆動が可能な小型多機能補助循環駆動装置を開発した。システムの概要は、1. 空気によるVASあるいはヘリウムガスによるIABPの駆動が可能である、2. コンプレッサー、バキュームユニット及びバッテリーを内蔵し、外部空圧源や電源がなくても作動可能である、3. 流量及び左房圧による定値制御が可能である、4. アラーム・バックアップ機構を有する、5. 空気流速計によるfull-fill to full-empty駆動(F/E駆動)が可能である。本装置について、モック、成山羊による慢性実験及び臨床例において評価を行った。その結果、VAS機構は、最長8週間の使用において特に問題を認めなかった。また、F/E駆動は、駆動圧の設定のみでマニュアル操作とほぼ同等のバイパス流量が得られた。IABP機構は、改良した心電トリガーにより不整脈への追従性は良好で、各種バルーンの特性にあわせた駆動条件の設定が可能であった。今回開発した駆動装置は、VAS及びIABPの駆動を良好に行い得、臨床上有用と考える。, JAPANESE SOCIETY FOR ARTIFICIAL ORGANS
人工臓器, 1992年04月 - 無拍動流肺循環の肺におよぼす影響に関する実験的検討-慢性期,覚醒状態下において-
榊雅之、妙中義之、巽英介、中谷武嗣、赤城治彦、増澤徹、後藤昌弘、佐々木栄作、井上和重、松尾義昭、馬場雄造、穴井博文、高野久輝, 覚醒動物の肺循環を拍動流から無拍動流へ迅速に転換させた時の肺循環動態および肺機能の変化を観察した。成山羊4頭に右心房右心室脱血, 肺動脈送血の国循型空気駆動式右心補助人工心臓(RVAS)を装着し, 肺循環を拍動流にて2週間維持した後, 覚醒状態下にRVASから遠心ポンプへ迅速に交換した。肺循環が無拍動流化することを確認し, 平均大動脈圧が拍動流肺循環時と等しくなるよう遠心ポンプのバイパス流量を設定した。この実験モデルにおいて, ポンプ交換前から交換後2週間目までの平均肺動脈圧, 肺血管抵抗係数, 動脈血ガス, 血中アンギオテンシン転換酵素濃度, 肺血流量分布(Colored Micro-sphere法)および肺の組織学的変化について検討した。ポンプ交換後2週間目までの検討では, いずれのパラメータも交換前と比較して有意な変化を認めなかった。以上より無拍動流肺循環は, 肺循環動態および肺機能に影響をおよぼさないと考える。, JAPANESE SOCIETY FOR ARTIFICIAL ORGANS
人工臓器, 1992年04月 - 左室圧-容積関係を用いたcardiomyoplastyの左心補助効果に関する実験的検討
後藤昌弘、中谷武嗣、榊雅之、妙中義之、巽英介、赤城治彦、増澤徹、佐々木栄作、馬場雄造、松尾義昭、井上和重、藤田毅、高野久輝, Cardiomyoplasty法(CMP)の左心補助効果について, 左室圧-容積関係を用い実験的検討を行った. 左側広背筋(LDM)に電気的トレーニングを行った正常心の成山羊5頭を用い実験を施行した. 左第5肋骨床開胸後, 心尖部よりvolume conductance catheterおよびcatheter-tip pressure transducerを左室に挿入し, 左室圧-容積曲線を描出させた. LDMを時計回りに心室の全周性に縫着し, CMPを行った. 圧-容積曲線群から, 左室のEes(左室収縮末期圧-容積関係)を求め, LDMの刺激による変化を検討した. また, 左室の拡張末期圧, 収縮末期圧, 一回拍出量, 拡張末期容積について同様の検討を行った. 今回の検討では, 左室圧-容積関係は, CMP時の左室機能の評価およびwrapping時の拡張障害回避に有用であったが, Eesおよびその他の測定項目においてCMPの明らかな左心補助効果を認めなかった. この結果より, 正常心成山羊を用いた急性実験ではCMPの左心補助の有効性を認めなかった., JAPANESE SOCIETY FOR ARTIFICIAL ORGANS
人工臓器, 1992年04月 - 胎盤を用いたハイブリッド型呼吸補助システムの試作
赤城治彦、高野久輝、妙中義之、中谷武嗣、木下正之、馬場雄造、巽英介、増澤徹、後藤昌弘、井上和重、榊雅之、松尾義昭、穴井博文、荒木賢二, 出産後不用となる人胎盤を用いて, 抗血栓性に優れたハイブリッド型呼吸補助システムを試作した. 患者血液は, 胎児さながら胎盤循環にてガス交換される. システムは, 胎盤循環回路および人工子宮循環回路より成り, 前者を患者血液が, 後者を酸素飽和した人工血液が灌流する. 両循環は, 胎盤絨毛膜を介して接触し, 単純拡散にてガス交換が行なわれる. In vitroで評価した試作システムのガス交換能は, 血流量1l/min, 人工血液流量3l/minの条件下で, 酸素添加能=60ml/min, 炭酸ガス除去能=40ml/minと良好であった. また, 胎盤に対する拒絶反応を山羊胎盤葉の同種移植実験にて検討したが, 移植した胎盤葉は1週間後も生着し, 明かな拒絶所見を認めなかった. 人胎盤を用いたハイブリッド型呼吸補助システムは, 実用化の可能性を有すると考える., JAPANESE SOCIETY FOR ARTIFICIAL ORGANS
人工臓器, 1992年04月 - Cardiovascular simulation using a multiple modeling method on a digital computer-Simulation of interaction between the cardiovascular system and angiotensin II
T MASUZAWA; Y FUKUI; NT SMITH, A cardiovascular system model that simulates interactive responses to drugs has been developed on a small digital computer. The overall model basically consists of three models. The first is a momentum transport model that represents relations between blood pressure and flow in the cardiovascular system. In this model, the cardiovascular system is divided into 14 components and modeled by using equivalent electrical circuits. The second is a mass transport model comprising 14 compartments corresponding to the respective components of the cardiovascular system. This model represents the distribution of the administered drug in the various cardiovascular components. The third is an interaction model that represents the relationships between the momentum and mass transport models. This model causes variations in the resistance and capacitance parameters of the momentum transport model as a function of the current drug concentrations in the appropriate compartments of the mass transport model. The capacitances representing the ventricles are varied in a time-dependent fashion to simulate the beat of the heart. Simulation is performed by using the Euler method to solve a system of 28 ordinary differential equations governing the momentum and mass transport models on a 32-bit microcomputer, a Macintosh II. The model was assessed by performing two demonstrations of the cardiovascular response to the vasopressor angiotensin II (AT II). They first examined the interaction between the cardiovascular system and AT II. The effect of AT II on the cardiovascular system was incorporated into the interaction model. Administration of AT II as a constant infusion (200-mu-g/hr) resulted in an elevation of mean arterial pressure from approximately 100 to 150 mm Hg. The second was a pharmacodynamic demonstration of the cardiovascular system in the presence of tumor tissue during induced-hypertension chemotherapy. A tumor tissue component was added to the cardiovascular system model, thereby incorporating into the interaction model the effects of blood pressure elevation on tumor tissue. The same administration of AT II as above resulted in an increase in blood flow from 0.3 and 1.3 ml/s (i.e., an increase of approximately 460%) in the carcinomatous tissue. The results, along with those obtained earlier with sodium nitroprusside, indicate that the present simulator could represent the cardiovascular system during administration of vasoactive drugs., KLUWER ACADEMIC PUBL
Journal of Clinical Monitoring, 1992年 - A motor integrated regenerative pump as the actuator of an electrohydraulic totally implantable artifical heart
T. Masuzawa; Y. Taenaka; M. Kinoshita; T. Nakatani; H. Akagi; H. Takano; Y. Fukui; H. Sasagawa; K. Takahashi, The authors have developed a new actuator to drive an electrohydraulic totally implantable artificial heart. The basic concept of this artificial heart is that the blood pumps are implanted in the thorax and an actuator is placed separately in the abdominal region. The actuator is a regenerative pump that pumps fluids against high pressures and is thin enough for easy implantation. The rotor-magnet of the brushless DC motor is mounted on the impeller of the pump to miniaturize the actuator and reduce the number of moving parts. The height, diameter, and weight of the actuator are 32.5 mm, 73 mm, and 360 g, respectively. A pair of oil ports is connected to the left and right blood pumps with mesh reinforced tubes filled with silicone oil. The blood pumps are alternately driven by bidirectional rotation of the motor. Performance of the system was evaluated in in vitro and in vivo experiments. Maximum output of the right heart was 6.7 L/min in both experiments. Systemic circulation was well maintained in acute animal experiments using 49 and 50 kg goats. The feasibility of the actuator was confirmed.
Trans Am Soc Artif Intern Organs, 1992年 - 腹壁内埋込み型左心補助人工心臓に関する基礎的検討
中谷武嗣、後藤昌弘、妙中義之、巽英介、赤城治彦、佐々木栄作、増澤徹、松尾義昭、関井浩義、矢倉明彦、高野久輝, 永久使用補助人工心臓(VAS)開発の第一段階として, 腹壁内埋込み型血液ポンプシステムについて検討した. 血液ポンプは国循型空気圧駆動diaphragm型を基に開発した. 心尖脱血用カニューラは, 左室心筋による圧迫閉塞防止のため従来の脱血カニューラ先端部に金属チップを埋没した. 成山羊を用い, ポンプ本体は左腹壁内に留置し, 脱血は左室心尖より, また送血は下行大動脈に行い, 駆動チューブは皮下トンネルを通して体外の駆動装置と接続した. 動物実験において, 本システムの装着および駆動は容易で, 3週間以上にわたり安定した血行動態を得ることが可能であった. またポンプの腹壁内収納にとくに問題はなく, 合併症も認めなかった. 本システムは, 長期左心補助に有用なシステムと考えた., JAPANESE SOCIETY FOR ARTIFICIAL ORGANS
人工臓器, 1991年08月 - Serum silicon levels in recipients of an electrohydraulic ventricular assist system
Yoshiaki Matsuo; Yoshiyuki Taenaka; Hisateru Takano; Takeshi Nakatani; Eisuke Tatsumi; Toru Masuzawa; Masahiro Goto; Akihiko Yagura; Haruhiko Akagi; Eisaku Sasaki; Kazusige Inoue; Masayuki Sakaki; Yuzo Baba; Tetsuzou Akutsu; Takeharu Ohumi; Kinji Tsukahara, This study was designed to determine the permeation rate of silicon oil from the authors' electrohydraulic ventricular assist system (EHVAS), and to evaluate influences on organ function. The permeation rate through the diaphragm of the EHVAS was determined by in vitro experiments. Influences on organ function were evaluated in three goats with EHVAS by monitoring blood chemical parameters and serum silicon levels (S-Si). The permeation rate from the EHVAS was about 0.2 ml/month, calculated from the data obtained in the in vitro experiments. S-Si levels did not increase during chronic animal implantation, and renal and hepatic function were not affected. The permeation rate through the diaphragm must, however, be taken into consideration.
ASAIO Transactions, 1991年07月, [査読有り] - Chronic evaluation of a compact nonseal magnet pump as a nonpulsatile pump for long-term use
Yoshiyuki Taenaka; Eisuke Tatsumi; Masayuki Sakaki; Eisaku Sasaki; Toru Masuzawa; Takeshi Nakatani; Haruhiko Akagi; Masahiro Goto; Yoshiaki Matsuo; Kazushige Inoue; Yuzo Baba; Masayuki Kinoshita; Hisateru Takano, Use of a nonpulsatile pump is one of the most interesting approaches in the development of artificial hearts. A centrifugal pump without a seal around the rotating part was evaluated in five goats. The size of the pump is 8.4 cm ×φ7.0 cm, including an electric motor. A polypropylene impeller with four fins on the top of a column in which a magnetic ring is embedded spins by coupling with a rotating magnet outside the housing. In the goats, the pump was placed paracorporeally to provide total left heart bypass at a flow rate of 4.6-7.6 L/min, and activated clotting time was controlled at 200-300 sec by continuous heparin infusion. Although the first three goats died within 3 days due to bleeding, embolism, and a jammed impeller, respectively, a pump could be driven for 14 days in the fourth goat, and another pump with a rotational control feedback system ran for 32 days in the fifth goat. Plasma free hemoglobin levels were 13.8 ± 4.3 mg/dl and 9.5 ± 2.5 mg/dl, and platelet counts were 53.8 ± 24.7 × 104/mm3 and 62.0 ± 22.0 × 104mm3 after 12 hours and 7 days pumping, respectively. No thrombus was observed in the blood chamber in the last two cases. In conclusion, this pump has possibilities as a nonpulsatile pump for long-term use.
ASAIO Transactions, 1991年07月, [査読有り] - Peripheral circulation during nonpulsatile systemic perfusion in chronic awake animals
Yoshiyuki Taenaka; Eisuke Tatsumi; Masayuki Sakaki; Eisaku Sasaki; toru Masuzawa; Takeshi Nakatani; Haruhiko Akagi; Masahiro Goto; Yoshiaki Matsuo; Kazushige Inoue; Yuzo Baba; Masayuki Kinoshita; Hisateru Takano, Peripheral circulation (PC) during nonpulsatile (NP) perfusion is not satisfactorily understood, although it is known that animals can survive with chronic NP flow. In awake goats, PC was analyzed by hemodynamic and hormonal parameters, tissue blood flow of the ear measured by a noninvasive laser Doppler flowmeter, and distribution of the body surface temperature monitored by thermography. An NP systemic circulation was established in five 40-64 kg goats with a centrifugal pump (MD-10, Iwaki Pump, Japan) that replaced a pulsatile ventricular assist device 2 weeks postoperatively
this was done without anesthesia. Nonpulsatile total left heart bypass was obtained, with flow rates of 78-165 ml/kg/min. Systemic vascular resistance and blood adrenalin and noradrenalin levels were not affected by the depulsation. Tissue blood flow during NP perfusion was well maintained and showed comparable values to those during pulsatile systemic circulation. Vasomotion of 10-20 cycles/min was obvious in the tissue blood flow pattern, indicating adequate PC at each sampling point. Thermography before and after depulsation indicated no change of temperature distribution, and displayed warm peripheral areas. In conclusion, PC of animals on chronic NP systemic perfusion is adequately maintained.
ASAIO Transactions, 1991年07月, [査読有り] - Hybrid respiratory support system with extracorporeal placental oxygenation
Haruhiko Akagi; Hisateru Takano; Yoshiyuki Taenaka; Takeshi Nakatani; Eisuke Tatsumi; Toru Masuzawa; Masahiro Goto; Eisaku Sasaki; Kazushige Inoue; Masayuki Sakaki; Yoshiaki Matsuo; Yuzo Baba, The authors developed a novel hybrid system for long-term respiratory support with extracorporeal placental oxygenation. In this system, the patient's blood is oxygenated with O2 saturated artificial blood across the villous membrane during passage through the fetal circuit of the placenta, which is placed in a specially constructed artificial uterus. Human term placentas were obtained immediately after vaginal delivery and used for the experiments. The gas transfer performance of the current apparatus was 60 ml/min for O2 and 40 ml/min for CO2 at a blood flow rate of 1.0 L/min. From these results (and the assured blood compatibility of the placenta), the authors conclude that this system will become one of the most promising modalities for prolonged extracorporeal oxygenation.
ASAIO Transactions, 1991年07月, [査読有り] - Integrated artificial heart-lung device
Eisuke Tatsumi; Hisateru Takano; Yoshiyuki Taenaka; Haruhiko Akagi; Takeshi Nakatani; Eisaku Sasaki; Masahiro Goto; Toru Masuzawa; Masayuki Sakaki; Yoshiaki Matsuo; Kazushige Inoue; Jun Kamo; Takanobu Aoyagi, An integrated artificial heart-lung device (IAHLD) is being developed as a novel system for simultaneous long-term support of heart and lung. The IAHLD consists of an artificial lung component (LC) and two blood pumps. The LC is made with a special composite hollow fiber membrane that prevents serum leakage. The fibers are arranged as piled-up lattices and potted in a cylindrical housing made of polyurethane. The blood pump with a single port is of a pneumatic pusher-plate type, and a Bjoerk-Shiley valve is mounted in the port. The LC is sandwiched between the inlet and outlet pumps, and all components are integrated. This special structure provides high gas exchange efficiency, prevention of flow channeling and stagnation, and reduction of blood contacting surfaces. The prototype IAHLD had exchange rates of up to 170 ml/min of O2 and CO2 and up to 5.5 L/min of pump output. A flow visualization analysis with cineroentgenography revealed that the flow distribution within the IAHLD was uniform, without any stasis. It was concluded that the IAHLD is a promising system for long-term heart and lung support, and can be used without systemic heparinization given thromboresistant surface treatment as the next step of development.
ASAIO Transactions, 1991年07月, [査読有り] - 完全体内埋込型エレクトロハイドローリック式全人工心臓の開発のための基礎的検討
妙中義之; 増澤 徹; 中谷武嗣; 矢倉明彦; 巽 英介; 関井浩義; 佐々木栄作; 赤城治彦; 後藤昌弘; 榊 雅之; 松尾義昭; 井上和重; 高野久輝, 完全体内埋込型全置換型人工心臓システムとして、胸腔内に血液ポンプを植え、腹腔内にアクチュエータを置くエレクトロハイドロ-リック式のシステムを試作した。本システムに用いる血液ポンプを、まず、空気駆動式として成熟動物である成山羊4頭(体重54kg~59kg、平均55.8±1.9kg)に植え込んで血液ポンプのみの生体内評価を行なったところ、最長40日間の生存例を得ることができ、エレクトロハイドローリック式のシステムを組み上げた際の長期評価への発展性が示唆された。次にアクチュエータと血液ポンプを組み合わせて模擬回路を用いたin vitro評価を行なった。アクチュエータは、ローラスクリュ機構により軸を往復運動させるDCブラシレスモータを、左右の血液ポンプとそれぞれ結合したプッシャープレートを有するポンプを用いた油室で挟み込んだ形式のもので、約6L/minの心拍出量を得ることができ、良好な拍出性能を示した。, JAPANESE SOCIETY FOR ARTIFICIAL ORGANS
人工臓器, 1991年06月 - 補助人工心臓からの離脱に有用な新しい駆動法を搭載した多機能補助循環駆動装置の開発と評価
佐々木栄作、中谷武嗣、高野久輝、妙中義之、巽英介、赤城治彦、関井浩義、矢倉明彦、後藤昌弘、増澤徹、榊誠之、松尾義昭、池田稔, 適切な補助循環法をより安全で効率的に実施するため、補助人工心臓(VAS)とIABPの両方を駆動できる多機能補助循環駆動装置を開発し、評価を行った。また本装置には、LVASからIABPへの円滑な離脱を行う目的で、新たに考案した心電同期交互駆動法(ASD)を搭載した。ASDは、LVASとIABPの1対1の交互駆動から、自己心の回復に従い徐々にIABPの拍数を増やしつつバイパス流量を減らして、自己心に急激な負担をかけずにLVASより離脱せしめる方法である。模擬循環回路及び動物実験での検討で、本装置はLVASあるいはIABP駆動装置として従来機種と同等以上の基本性能を有し、またASDもLVASとIABPの能力格差を埋める力法として有効であることが確認された。本装置を巨大左室瘤切除後の62歳男性患者のLVASからの離脱に適用したが、ASDにより循環動態を悪化させる事なくバイパス流量を減らし得た。本装置は円滑な補助循環の運用を可能にし、救命率向上に寄与すると考える。, JAPANESE SOCIETY FOR ARTIFICIAL ORGANS
人工臓器, 1991年 - エレクトロハイドローリック方式補助人工心臓システムの改良と慢性動物実験による性能評価
松尾義昭、矢倉明彦、妙中義之、高野久輝、中谷武嗣、巽英介、赤城治彦、関井浩義、佐々木栄作、後藤昌弘、増澤徹、榊雅之、阿久津哲造、大海武晴、土本勝也, 従来から開発してきたリニアアクチュエータを用いたエレクトロハイドローリック方式補助人工心臓システムの駆動性能を、成山羊4頭(54~68kg)を用いた慢性実験により評価した。併せて新たに開発した吸引圧自動調節機構(ANPC)の心房壁の吸い付きを防止する効果を検討した。血液ポンプの抗血栓性の問題で、術後5日目に実験を中止せざるを得なかった1頭を除いて、実験動物の血行動態は良好に維持された。4頭での最大バイパス流量は5.8L/minであり、21~42日間充分な流量を安定して維持する駆動性能を示した。ANPCを使用しなかった成山羊ではアクチュエータの吸引により左房圧は、瞬時圧で最大-80mmHgの陰圧を示したが、ANPCの使用により-10mmHgに維持された。またANPCを使用した実験動物の左房内壁には吸い付きの所見を認めなかった。ANPCにより心房壁の吸い付きは防止され、改良された本システムは長期携帯可能な補助人工心臓システムへ発展可能であると考える。, JAPANESE SOCIETY FOR ARTIFICIAL ORGANS
人工臓器, 1991年 - 実験動物の無拍動流体循環への生理学的適応過程の検討
妙中義之、巽英介、榊雅之、佐々木栄作、中谷武嗣、赤城治彦、関井浩義、矢倉明彦、後藤昌弘、増澤徹、松尾義昭、井上和重、高野久輝, 無拍動流体循環への動物の生理学的適応過程を検討するために、成山羊5頭を用いて慢性動物実験を行なった。国立循環器病センター型補助人工心臓を左房左室脱血、大動脈送血による100%バイパスができるように装着し、2週間後に覚醒下に遠心ポンプ(MD-10、イワキポンプ)にすばやく取り替え、平均大動脈圧を無拍動流化前後で一定に保つように駆動した。その結果、体循環を無拍動流化しても拍動流時と比較して、右房圧、灌流量、全末梢血管抵抗、全身酸素消費量、血清乳酸値、血中カテコラミン値(アドレナリン値およびノルアドレナリン値)、血漿レニン活性、血漿アンギオテンシンII値、血漿アルドステロン値、には変化はみられず、また、volume負荷の必要もなかった。以上より、体循環の無拍動流化に対して、動物は速やかに生理学的に順応すると考えられた。, JAPANESE SOCIETY FOR ARTIFICIAL ORGANS
人工臓器, 1991年 - 異常認識機構を有した血圧制御システム
増澤 徹, 本研究では, ファジィ制御の上位に異常認識機能を付加した, より安全な生体用自動制御機構を開発した.基本となる制御系にファジィ理論を導入することにより, 医師の経験則に基づいた血圧制御系を構築し, 制御方式を実際の医師の施行に近いものとした.その結果, 医療現場への導入に先立ち, 医師より良好な評価を得た.異常認識部では時系列信号の推移認識に基づき制御状態の評価を行い, 異常制御時に制御系に介入する機能により, 閉ループ制御の安全性を高めた.シミュレーションおよび動物実験の結果より本制御方式の有効性が確認された., 公益社団法人精密工学会
精密工学会誌, 1990年08月 - An electorohydraulic total artificial heart with a separately placed actuator
Y.Taenaka; H.Sekii; E.Tatsumi; T.Nakatani; E.Sasaki; A.Yagura; H.Akagi; T.Masuzawa; M.Goto; Y.Matsuo; And H.Takano, An electrohydraulic total artificial heart (EHTAH) system, consisting of a separately placed actuator and blood pumps with good anatomic fit, was designed. In the actuator is a brushless DC motor sandwiched between two metal bellows or two pusher-plate pumps connected with the blood pumps by polyvinylchloride tubes. A roller-screw system coupled with the bellows is used for alternative pumping, and silicone oil transmits the action. The pumps are elliptical, and the right pump has a flatter and longer shape than the left to fit the extremely short distance between the right atrium and the sternum. To evaluate in vivo performance, the pumps were implanted as a pneumatic system in a calf weighing 53 kg and three goats weighing 54-55 kg. The pump fit well in the animals, and the calf survived for 111 days, and one goat was alive for 8 days. The EHTAH system could provide an output of 6 L/min with pusher-plate pumps as oil chambers on in vitro evaluation. This system could become one of the most suitable approaches for a totally implantable system.
ASAIO Transaction, 1990年 - 介助用小型軽量マニプレータの開発
藤記拓也,土肥健純,増澤 徹, In these several years, the number of aged people in Japan has increased, and for some other reasons, there has risen the problem of people who take care of the bedridden patients in daily life. And it is.expected that this kind of probkem would be more serious in the future. As one solution to the this problem, we've developed some manipulator systems which aid the nursing of bedridden patients. But the traditional manipulator is not powerful enough to be used in practice.In order to overcome this disadvantage in power, we developed a new type manipulator which is more powerful than the traditional one, by using the wire-driving mechanism. This mechanism has been thought to be useless, because the length of wire changes as the load changes, and it is difficult to know the precise position of the end effector. This time, we have solved this problem by putting high resolution encoders at each joint and sensing the displacement of the joints directly. As the result, we succeeded in developing a new type manipulator more powerful than the traditional one. And for controllability, we took the dual-PID control algorithm and improved the controlling characteristic., THE SOCIETY OF LIFE SUPPORT ENGINEERING
エル・エス・ティ学会誌, 1989年05月 - 帯磁コンタクトレンズを用いた無拘束眼球運動計測システムの開発
鎮西清行,土肥健純,増澤 徹, Nystagmus measurement is quite useful and popular for equilibrium function test. To measure it, several kinds of methods. for example, Electro-Nystagmography(ENG, orEOG) are developed and clinically used. But they have some problems. To solve those problems, such as the drift or noise on the output signal, or the improper restriction of the free movement of the subject's body and eyeball, we propose the following new measuring method. We adopted the magnetic measuring method, and constructed a prototype system. In this system, a set of magnetic sensors detects magnetic flux density of the magnetic contact lens. worn on the eyeball of the subject And using this system, we confirm the availability of this system., THE SOCIETY OF LIFE SUPPORT ENGINEERING
エル・エス・ティ学会誌, 1989年05月 - マン・マシン・インターフェースを考慮した聴覚障害児童のための発声発語訓練装置の開発
楢原弘之、土肥健純、堀内孝、増澤徹, In this report, a basic principle of designing on effective man-machine interface is given to construct a speech training system based upon the information theory. Although the speech training system has been developed by our group, its evaluation in a field-testing indicated a need for correction in this system. In order to keep trainee's attention, a program on the display has to be attractive. Concerning these problems the newly designed inexpensive training system is constructed using the home computer MSX 2 and the speech processing interface board. The signals are picked up by a microphone, and then pass through a low pass filter which cut-off frequency is controllable by the micro computer. The analogue signals are converted to digital ones by the A/D convertor. The signal processor (μPD 7720) is adopted to find the peaks of the power spectrum which is realized by the cascaded 4 signal processors arrangement. Using the MSX 2 graphic functions, the result of this analysis is presented to trainee. This system could be utilized in the first three stage of speech training; basic vocalization;intensity, duration, pitch; pronounciation of specific vowels and dipthongs., 日本医療機器学会
医科器械学, 1988年08月 - アウターロータ型5軸制御セルフベアリングモータの開発
松田 健一; 寺山 昌幸; 近藤 良; 増澤 徹
日本機械学会論文集C編, 1911年05月, [査読有り]
MISC
- 磁気浮上型人工心臓
増澤徹
日本AEM学会誌, 2017年09月10日, [査読有り], [招待有り]
筆頭著者 - 人工心臓の磁気浮上方式の現在と将来
増澤 徹
電気学会誌, 2015年09月, [招待有り]
筆頭著者 - 補助人工心臓とベアリング技術
増澤徹
ベアリング新聞, 2015年06月05日, [招待有り] - 退院できる補助人工心臓
増澤徹
日本機械学会誌, 2015年02月, [招待有り] - ゼロパワー制御を用いた磁気浮上全人工心臓の流量バランス制御
山田悠; 増澤徹; ティムズダニエル
電気学会研究会資料 リニアドライブ研究会 LD-13-083〜103, 2013年10月07日 - 生体組織融着技術を用いた血管吻合装置の開発-加圧バンドを用いた場合の融着強度評価-
橋本一生; 柴建次; 岸田晶夫; 尾関和秀; 増澤徹
電気学会研究会資料 リニアドライブ研究会 LD-13-083〜103, 2013年10月07日, [査読有り] - 生体組織融着技術を用いたステントの位置ずれ防止-小型コイルによるステントの誘導加熱と引張強度評価-
田代翔子; 橋本一生; 柴建次; 岸田晶夫; 尾関和秀; 増澤徹
日本機械学会関東支部・精密工学会・茨城大学茨城講演会講演論文集, 2013年 - 802 単一磁気浮上モータを用いた全置換型人工心臓の研究開発(OS5-1 オーガナイズドセッション《ライフサポートにおける工学技術》)
坂田 佑介; 増澤 徹; 西村 宣彦; Timms Daniel L
茨城講演会講演論文集 : Ibaraki district conference, 2012年08月24日 - 806 小型・高性能アウターロータ型5軸制御セルフベアリングモータの開発(OS5-2 オーガナイズドセッション《ライフサポートにおける工学技術》)
平根 龍也; 松田 健一; 近藤 良; 増澤 徹
茨城講演会講演論文集 : Ibaraki district conference, 2012年08月24日 - A radial type self-bearing motor for small maglev regenerative blood pump
Keigo Ukita; Toru Masuzawa; Hiroyuki Onuma; Takashi Nishimura; Shunei Kyo
第20回MAGDAコンファレンスProceedings, 2011年11月14日 - 139 IPM型5軸制御セルフベアリングモータの永久磁石配置に関する研究(セルフベアリングモータ,OS-23 磁気浮上・磁気軸受,総合テーマ:「部門創設25周年、新たなる躍動」)
松田 健一; 佐藤 心平; 近藤 良; 増澤 徹; TERAYAMA Masayuki
機械力学・計測制御講演論文集, 2011年09月04日 - 407 IPM型5軸制御セルフベアリングモータに関する研究(OS5-(3)オーガナイズドセッション《ライフサポートにおける工学技術》)
佐藤 心平; 松田 健一; 近藤 良; 増澤 徹
茨城講演会講演論文集 : Ibaraki district conference, 2011年08月26日 - EVALUATION OF THE MAGLEV MOTOR AND DESIGN OF THE CENTRIFUGAL BLOOD PUMP FOR PEDIATRIC ARTIFICIAL HEART
M. Osa; T. Masuzawa; E. Tatsumi
INTERNATIONAL JOURNAL OF ARTIFICIAL ORGANS, 2011年08月 - Surface characteristics and bonding of medical polymeric material
Nakamura N; Nam K; Kimura T; Masuzawa T; Okada T; Kishida A
東京医科歯科大学生体材料工学研究所年報, 2011年 - Surface characteristics and bonding of medical polymeric material
Nakamura N; Nam K; Kimura T; Masuzawa T; Okada T; Kishida A
東京医科歯科大学生体材料工学研究所年報, 2011年 - 732 アウターロータ型5軸制御セルフベアリングモータの開発(開発,OS-23 磁気浮上・磁気軸受,総合テーマ「伝統を,未来へ!」)
松田 健一; 寺山 昌幸; 近藤 良; 増澤 徹
Dynamics & Design Conference, 2010年09月14日 - Journal of Artificial Organs 2009:the year in review
Sawa Y; Tatsumi E; Funakubo A; Horiuchi T; Iwasaki K; Kishida A; Masuzawa T; Matsuda K; Nishimura M; Nishimura T; Tomizawa Y; Yamaoka T; Watanabe H
J Artif Organs, 2010年 - 医用アクチュエーション技術の体系化に関する協同研究委員会活動報告
増澤徹,福長一義,小沼弘幸,住倉博仁
平成21年電気学会産業部門応用部門大会, 2009年08月31日 - 1008 人工心臓適用を目指した5軸制御セルフベアリングモータの小型化に関する研究(OS2-(2) ライフサポートにおける工学技術,オーガナイズドセッション)
寺山 昌幸; 松田 健一; 近藤 良; 増澤 徹
茨城講演会講演論文集 : Ibaraki district conference, 2009年08月25日 - 165 オンチップ細胞機能制御のための圧電駆動型マイクロ細胞培養デバイス開発(OS4-2モノ作りと生産システム2)
松澤 勇太; 柴田 隆行; 川島 貴弘; 増澤 徹; 岸田 晶夫
東海支部総会講演会講演論文集, 2009年03月01日 - 138 磁気浮上型人工心臓の浮上インペラの挙動と流体力解析(OS1-6:循環器系のバイオメカニクス(6),OS1:循環器系のバイオメカニクス)
小沼 弘幸; 増澤 徹
バイオエンジニアリング講演会講演論文集, 2009年01月22日 - Journal of Artificial Organs 2008:the year in review
Sawa Y; Tatsumi E; Funakubo A; Horiuchi T; Iwasaki K; Kishida A; Masuzawa T; Matsuda K; Nishimura M; Nishimura T; Tomizawa Y; Yamaoka T; Watanabe H
J Artif Organs, 2009年 - 257 細胞機能制御のための圧電駆動型マイクロ細胞培養チップの開発(OS2-2 最先端加工技術の基礎と応用(2),OS2 最先端加工技術の基礎と応用)
脇坂 健司; 松澤 勇太; 柴田 隆行; 川島 貴弘; 増澤 徹; 岸田 晶夫
東海支部総会講演会講演論文集, 2008年03月01日 - 扁平型ハイブリッド磁気軸受の最適化設計
加藤綾子,増澤徹,鈴木健一
第20回「電磁力関連のダイナミクス」シンポジウム講演論文集, 2008年 - Journal of Artificial Organs 2007:the year in review
Sawa Y; Tatsumi E; Funakubo A; Horiuchi T; Iwasaki K; Kishida A; Masuzawa T; Matsuda K; Nishimura M; Nishimura T; Tomizawa Y; Yamaoka T; Watanabe H
J Artif Organs, 2008年 - 扁平型ハイブリッド磁気軸受の開発
鈴木健一、増澤徹
第16回MAGDAコンファレンスin京都講演論文集, 2007年11月22日 - 5軸能動制御型セルフベアリングモータの開発
松田健一、石川達也、増澤徹、近藤良
第16回MAGDAコンファレンスin京都講演論文集, 2007年11月22日 - 磁気軸受用センサの開発
岡田養二、石川達也、増澤徹、近藤良
第16回MAGDAコンファレンスin京都講演論文集, 2007年11月22日 - 人工心臓のための小型ハイブリッド型磁気軸受
増澤徹、鈴木健一、黒須寛秋、加藤綾子
電気学会研究会資料LD-07-32~49, 2007年10月26日 - 207 ダブルバイアス磁束型磁気浮上血液ポンプの開発(ライフサポートにおける工学技術)
佐々木 瑛祐; 増澤 徹; 小沼 弘幸
茨城講演会講演論文集 : Ibaraki district conference, 2007年09月28日 - 磁気浮上技術と医用アクチュエーション
増澤 徹
平成19年度電気学会産業応用部門講演論文集, 2007年08月21日 - 人工心臓の最近の進歩
増澤徹
体外循環と補助循環2007第23回教育セミナー(日本人工臓器学会), 2007年07月10日, [招待有り] - 人工心臓用ダブルバイアス磁束型磁気浮上システム
増澤徹; 加藤裕介,佐々木瑛祐,小沼弘幸
第19回電磁力関連のダイナミクスシンポジウム講演論文集, 2007年05月 - Journal of Artificial Organs 2006:the year in review
Sawa Y; Horiuchi T; Kishida A; Masuzawa T; Nishimura M; Tatsumi E; Tomizawa Y; Watanabe H
J Artif Organs, 2007年 - Active mask UV lithography systme for MEMS and μTAS applications
Terutake Hayashi; Takayuki Shibata; Takahiro Kawashima; Eiji Makino; Takashi Mineta; Toru Masuzawa
Proceedings of the 21st Annual ASPE Meeting, ASPE 2006, 2006年12月01日 - 203 人工心臓用磁気軸受の最適設計(ライフサポートにおける工学技術)
中山 直久; 増澤 徹; 加藤 綾子; 鈴木 健一
茨城講演会講演論文集 : Ibaraki district conference, 2006年09月14日 - 204 バイアス磁束誘導型磁気浮上人工心臓の開発(ライフサポートにおける工学技術)
加藤 裕介; 増澤 徹
茨城講演会講演論文集 : Ibaraki district conference, 2006年09月14日 - Optimized Design for a Hybrid Magnetic Bearing for the Artificial Heart
Katoh A; Masuzawa T
Proceedings for the Tenth International Symposium on Magnetic Bearings: CD-ROM, 2006年08月 - Journal of Artificial Organs 2005:the year in review
Sawa Y; Horiuchi T; Kishida A; Masuzawa T; Mizuguchi K; Nishimura M; Okoshi T; Shinzato T; Tatsumi E; Tomizawa Y; Watanabe H
J Artif Organs, 2006年 - 人工心臓(基礎)
増澤徹
人工臓器, 2006年 - 電気駆動型人工心臓の開発状況
増澤 徹; Toru MASUZAWA
日本AEM学会誌 = Journal of the Japan Society of Applied Electromagnetics, 2005年09月10日 - 703 人工心臓用アキシャル型磁気浮上遠心ポンプの小型化(関東支部 茨城講演会)
加藤 裕介; 増澤 徹
茨城講演会講演論文集 : Ibaraki district conference, 2005年09月08日 - 10311 人工心臓用3軸制御型磁気浮上遠心ポンプの開発(OS5 バイオメカトロニクス)
加藤 裕介; 村上 倫子; 小沼 弘幸; 増澤 徹
日本機械学会関東支部総会講演会講演論文集, 2005年03月17日 - セルカルチャーのための圧電駆動型マイクロ細胞培養チップの開発(オーガナイズドセッション,ライフサポートにおける工学技術)
蒔田 喜之; 柴田 隆行; 増澤 徹; 岸田 晶夫; 牧野 英司
茨城講演会講演論文集 : Ibaraki district conference, 2004年09月23日 - ナノバイブレーションによる細胞増殖促進装置の開発(オーガナイズドセッション,ライフサポートにおける工学技術)
草間 淳; 石丸 正臣; 増澤 徹; 木村 孝之; 柴田 隆行; 岸田 晶夫
茨城講演会講演論文集 : Ibaraki district conference, 2004年09月23日 - Mixed venous oxygen saturation as a promising parameter for physiologic control of total artificial heart
M Nakamura; A Homma; E Tatsumi; K Uesho; Y Taenaka; T Masuzawa; T Nakamura; B Zhang; Y Kakuta; K Imada; T Nakatani; H Takano
ASAIO JOURNAL, 2000年11月 - In vivo long term evaluation of transcutaneous energy transmission for tatally implantable artifitial heart
Y. Kakuta; E. Tatsumi; Y. Taenaka; K. Uesho; A. Homma; M. Nakamura; T. Masuzawa; K. Shiba; K. Koshiji
ASAIO Journal, 2000年 - Current status of development and in vivo evaluation of the National Cardiovascular Center electrohydraulic total artificial heart system
Eisuke Tatsumi; Yoshiyuki Taenaka; Kunihiro Uesho; Akihiko Homma; Tomohiro Nishinaka; Yukihide Kakuta; Tomonori Tsukiya; Hisateru Takano; Toru Masuzawa; Makoto Nakamura; Kohji Koshiji; Yasuhiro Fukui; Kinji Tsukahara; Katsuya Tsuchimoto; Hideki Wakui
Journal of Artificial Organs, 2000年 - Effects of long-term nonpulsatile left heart bypass on the mechanical properties of the aortic wall
T Nishimura; E Tatsumi; Y Taenaka; T Nishinaka; T Nakatani; T Masuzawa; M Nakata; M Nakamura; S Endo; H Takano
ASAIO JOURNAL, 1999年09月 - Importance of metabolic function of the natural lung evaluated by prolonged exclusion of the pulmonary circulation
Kazuhiro Eya; Eisuke Tatsumi; Yoshiyuki Taenaka; Yoshiaki Takewa; Koichi Toda; Yoshinari Wakisaka; Takeshi Nakatani; Toru Masuzawa; Yuzo Baba; Koji Miyazaki; Takashi Nishimura; Takashi Ohno; Jae Mok Ahn; Haruhiko Akagi; Hisateru Takano
ASAIO Journal, 1996年
書籍等出版物
- 磁気浮上技術の原理と応用
分担執筆
科学情報出版株式会社, 2018年03月
9784904774656 - Mechanical Circulatory and Respiratory Support
Edited by Gregory; Stevens & Fraser, 共著
Elsevier, Academic Press, 2017年10月
9780128104910 - 南山堂医学大辞典 第20版
共著
南山堂, 2015年04月 - 増補新訂版 人工臓器は,いま
共著
はる書房, 2012年12月 - ひとの暮らしと表面科学(現代表面科学シリーズ5)
日本表面科学会編集, 共著
共立出版株式会社, 2011年07月
9784320033702 - ヘルスケアとバイオ医療のための先端デバイス機器
三林浩二監修, 共著
シーエムシー出版, 2009年05月
9784781301204 - 人工臓器イラストレテッド
日本人工臓器学会編集, 共著
はる書房, 2007年11月
9784899840800 - 人工臓器は,いま
日本人工臓器学会編集, 共著
はる書房, 2003年11月
4899840454 - Clinical application of Computational Mechanics to the Cardiovascular System, T. Yamaguchi(Ed.)
共著
Springer, 2000年 - ME用語辞典
日本エム・イー学会編, 共著
コロナ社, 1999年09月
講演・口頭発表等
- 体内植込み型小児用補助人工心臓のための小型・扁平磁気浮上モータの研究
河村幹也; 長真啓; 北山文矢; 増澤徹; 西中知博
第33回ライフサポート学会フロンティア講演会, 2024年03月
202403, 202403 - アキシャル型全人工心臓用磁気浮上モータの改良
江藤絢平; 増澤徹; 今野美紗紀; 桑本真子; 北山文矢; 長真啓
第33回ライフサポート学会フロンティア講演会, 2024年03月
202403, 202403 - ホモポーラ型磁気浮上モータを用いた全置換型人工心臓の研究
鈴木修太; 増澤徹; 長真啓; 北山文矢; 信太宗也
第33回ライフサポート学会フロンティア講演会, 2024年03月
202403, 202403 - 磁気浮上血液ポンプにおけるスクイーズ効果の検討
谷平健心; 増澤徹; 後藤結帆; 長真啓; 北山文矢
第33回ライフサポート学会フロンティア講演会, 2024年03月
202403, 202403 - ホモポーラ型磁気浮上モータを用いた全置換型人工心臓の制御システムの構築
平口航士朗; 増澤徹; 佐藤光志朗; 鈴木修太; 長真啓; 北山文矢
第33回ライフサポート学会フロンティア講演会, 2024年03月
202403, 202403 - 5軸制御セルフベアリングモータの三相駆動・制御システムの開発
村山優心; 長真啓; 長澤優樹; 北山文矢; 増澤徹
第33回ライフサポート学会フロンティア講演会, 2024年03月
202003, 202403 - 磁気浮上式血液ポンプにおける粘性流体送液時のインペラ支持性能
長真啓; 増澤徹; 北山文矢; 西中知博; 築谷朋典; 巽英介
第32回MAGDAコンファレンスin 金沢, 2023年11月
202311, 202311 - 小児用補助人工心臓用磁気浮上モータのセンサレス制御化
小橋優輝; 長真啓; 増澤徹; 北山文矢; 西中知博
第32回MAGDAコンファレンスin 金沢, 2023年11月
202311, 202311 - Pediatric ventricular assist device and artificial hearts with magnetic levitation mechanism
Toru Masuzawa
11th Asan Medical Center Biomedical Engineering Center Symposium, 2023年11月
202311, 202311 - Magnetic bearing of maglev total artificial heart
Toru MASUZAWA; Misaki KONNO; Mako KUWAMOTO; Masahiro OSA; Fumiya KITAYAMA
21st International Symposium on Applied Electromagnetics and Mechanics, 2023年11月
202311, 202311 - NPOオーファンデバイス研究開発の設立
増澤徹; 小野稔; 松宮護郎; 岸田晶夫
第61回日本人工臓器学会大会, 2023年11月
202311, 202311 - Magnetic Levitation Technology for MCS
TORU MASUZAWA
The 29th annual meeting of The International Society for Mechanical Circulatory Support, 2023年10月, [招待有り]
202310, 202311 - Magnetic levitation technology for artificial heart
Toru Masuzawa
APSAO 2023 Conference, 2023年09月, [招待有り]
202309, 202309 - 完全置換型磁気浮上人工心臓の流量バランス制御機能向上のための研究
桑本真子; 増澤徹; 長真啓; 信太宗也; Daniel L Timms
Life2023, 2023年09月
202309, 202309 - 小児用磁気浮上型補助人工心臓の粘性液体下におけるポンプ性能とインペラ支持性能評価
佐藤遼一郎; 長真啓; 増澤徹; 北山文矢
第31回茨城講演会, 2023年08月
202308, 202308 - 分割巻線を用いた磁気浮上小児用補助人工心臓の性能評価
長澤優樹; 長真啓; 北山文矢; 増澤徹
第31回茨城講演会, 2023年08月
202308, 202308 - チタン合金壁通過型渦電流変位センサの特性評価
菅原槙人; 増澤徹; 長真啓; 北山文矢; 柴健次
第31回茨城講演会, 2023年08月
202308, 202308 - ラジアル型全人工心臓用磁気浮上モータの改良
佐藤光志朗; 増澤徹; 鈴木修太; 長真啓; 北山文矢
第31回茨城講演会, 2023年08月
202308, 202308 - 体内植込型全人工心臓のためのホモポーラ型磁気浮上モータ
鈴木修太; 増澤徹; 川口哲平; 長真啓; 北山文矢
第35回「電磁力関連のダイナミクス」シンポジウム, 2023年06月
202306, 202306 - 出力シャフトに永久磁石を配置した人工心臓用MR変速機
北山文矢; 増澤徹; 佐藤樹; 長真啓
第35回「電磁力関連のダイナミクス」シンポジウム, 2023年06月
202306, 202306 - 体内埋め込みを目指した磁気浮上型小児用人工心臓の駆動システムの研究開発
長澤優樹; 長真啓; 北山文矢; 増澤徹
第32回ライフサポート学会フロンティア講演会, 2023年03月
202303, 202303 - ホモポーラ型磁気軸受を用いたラジアル型磁気浮上全人工心臓の研究
佐藤光志朗; 増澤徹; 長真啓; 北山文矢
第32回ライフサポート学会フロンティア講演会, 2023年03月
202303, 202303 - 人工心臓のためのハイブリッド型MR流体変速機の研究
佐藤樹; 増澤徹; 北山文矢; 長真啓
第32回ライフサポート学会フロンティア講演会, 2023年03月
202303, 202303 - 低損失・高い磁気支持性能を有する小児用補助人工心臓用磁気浮上モータの研究
佐藤遼一郎; 長真啓; 北山文矢; 増澤徹
第32回ライフサポート学会フロンティア講演会, 2023年03月
202303, 202303 - 磁気浮上補助人工心臓のための小型制御システムの開発
齋藤広明; 増澤徹; 長真啓; 北山文矢
第32回ライフサポート学会フロンティア講演会, 2023年03月
202303, 202303 - 磁気浮上技術と人工心臓
増澤徹
第32回ライフサポート学会フロンティア講演会, 2023年03月, [招待有り]
202303, 202303 - Magnetic Suspension Stability of a Compact Axial Flux Self-Bearing Motor for Implantable Pediatric Rotary Blood Pumps
Osa Masahiro; Toru Masuzawa
18th International Symposium on Magnetic Bearings, 2023年02月
202302, 202302 - 小児用補助人工心臓のための磁気浮上型遠心ポンプの性能評価
長真啓; 増澤徹; 西中知博; 築谷朋典; 水野敏秀; 梅木昭秀; 巽英介
第51回人工心臓と補助循環懇話会学術集会, 2023年02月
202302, 202302 - 小児用補助人工心臓用5軸制御セルフベアリングモータの駆動系簡素化の検討
長真啓; 増澤徹; 北山文矢; 西中知博; 巽英介
第31回MAGDAコンファレンス, 2022年11月
202211, 202211 - 磁気浮上人工心臓のための制御周波数の検討
齋藤広明; 増澤徹; 長真啓; 北山文也
第31回MAGDAコンファレンス, 2022年11月
202211, 202211 - Magnetically levitated mechanical circulatory support systems
T. Masuzawa; M. Osa; T. Nishinaka; D. Timms
the 48th Annual Congress of the European Society for Artificial Organs, 2022年09月
202209, 202209 - 小児用補助人工心臓用磁気浮上モータの外径拡大による高支持力・高トルク化の検討
小橋優輝; 長真啓; 増澤徹; 西中智博
第30回茨城講演会, 2022年08月
202208, 202208 - 両心室シャント構造を持つ完全置換型磁気浮上人工心臓のポンプ性能
桑本真子; 増澤徹; 長真啓; 信太宗也; Daniel L Timms
第30回茨城講演会, 2022年08月
202208, 202208 - 体内埋込み型磁気浮上式小児用補助人工心臓の動物実験に向けた改良
長真啓; 増澤徹; 西中知博; 築谷朋典; 巽英介
第34回「電磁力関連のダイナミクス」シンポジウム, 2022年05月
202205, 202205 - 磁気浮上人工心臓における制御周波数と浮上安定性の関係
齋藤広明; 増澤徹; 長真啓
第34回「電磁力関連のダイナミクス」シンポジウム, 2022年05月
202205, 202205 - 小児用補助人工心臓用磁気浮上モータの省エネルギー化と支持性能の向上
小橋優輝; 増澤徹; 長真啓
第31回ライフサポート学会フロンティア講演会, 2022年03月
202203, 202203 - 複合低エネルギーを用いた自己接合型脱血管の実用化に向けた検討
鈴木修太,増澤徹,長真啓,西中智博
第31回ライフサポート学会フロンティア講演会, 2022年03月
202203, 202203 - 磁気浮上型小児用補助人工心臓の高度化に関する研究
山下俊大; 増澤徹; 長真啓; 巽英介; 西中智博
第31回ライフサポート学会フロンティア講演会, 2022年03月
202203, 202203 - ホモポーラ磁気軸受を用いた人工心臓磁気浮上モータの研究開発
川口哲平; 増澤徹; 長真啓
第31回ライフサポート学会フロンティア講演会, 2022年03月
202203, 202203 - テンセグリティ細胞模擬ロボットのソレノイドアクチュエータの検討
桑本真子,増澤徹,長真啓
第31回ライフサポート学会フロンティア講演会, 2022年03月
202203, 202203 - 小児用補助人工心臓用磁気浮上モータの異なる制御軸数における磁気支持性能と電力特性の評価
山下俊大; 増澤徹; 長真啓; 巽英介; 西中知博
第30回MAGDAコンファレンス, 2021年12月
202112, 202112 - 改良型遠心ポンプの改善点報告と実機評価,小型遠心血液ポンプを用いた磁気浮上型小児用補助人工心臓の研究開発
長真啓; 山下俊大; 増澤徹; 西中知博; 築谷朋典; 水野敏秀; 片桐伸将; 巽英介; 柳園宣紀; 一ノ瀬高紀
日本定常流ポンプ研究会学術集会202, 2021年11月
202111, 202111 - 乳幼児用体内埋込み型補助人工心臓開発に向けた数値流体解析による磁気浮上式遠心血液ポンプ設計の検討
信太宗也,増澤徹,築谷朋典,長真啓,西中知博,巽英介
第59回日本人工臓器学会大会, 2021年11月
202111, 202111 - 超小型な磁気浮上モータを用いた小児用人工心臓の性能評価
長真啓; 山下俊大; 増澤徹; 西中知博; 築谷朋典; 水野敏秀; 片桐伸将; 巽英介; 柳園宜紀; 一ノ瀬高紀
第59回日本人工臓器学会大会, 2021年11月
202111, 202111 - 埋め込み型補助人工心臓のための緊急エネルギ維持機構
LIFE2020-2021, 2021年09月
202109, 202109 - 模擬循環回路による補助循環下の冠循環流量評価
LIFE2020-202, 2021年09月
202109, 202109 - 完全置換型磁気浮上人工心臓のポンプ特性
對馬謙一; 増澤徹; 長真啓; 信太宗也; Timms Daniel
LIFE2020-202, 2021年09月
202109, 202109 - 小児用人工心臓用アキシャル型セルフベアリングモータの動特性評価
長真啓,増澤徹,築谷朋典,西中知博,巽英介
Dynamics and Design Conference 2021, 2021年09月
202109, 202109 - Dynamic Suspension Performance of an Ultra-Compact 5-DOF Controlled Axial Gap Type Self-Bearing Motor for Use in Pediatric Ventricular Assist Device
Masahiro Osa; Toru Masuzawa; Toshihiro Yamashita; Eisuke Tatsumi
The 17th International Syimposium on Magnetic Bearings, 2021年08月
202108, 202108 - 小児用人工心臓用磁気浮上モータの小型化に関する研究
第33回「電磁力関連のダイナミクス」シンポジウム, 2021年05月
202105, 202105 - 体内植込型補助人工心臓のためのホモポーラ型磁気浮上モータ
川口哲平,増澤徹,長真啓
第33回「電磁力関連のダイナミクス」シンポジウム, 2021年05月
202105, 202105 - 人工心臓のためのホモポーラ型磁気軸受の支持力向上の検討
上田優人,増澤徹,長真啓,Megan Kavin
第31回「電磁力関連のダイナミクス」シンポジウム, 2019年05月 - 全置換型磁気浮上人工心臓の右心ポンプ性能の向上に関する研究
牧田丈靖,増澤徹,信太宗也,長真啓,Daniel L Timms,
第28回ライフサポート学会フロンティア講演会, 2019年03月 - 小児用補助人工心臓用磁気浮上モータの省エネルギー化に関する研究
山口清,増澤徹,長真啓,織原涼雅,巽英介
第28回ライフサポート学会フロンティア講演会, 2019年03月 - 埋込型人工心臓への使用を目的とした緊急時電力供給用小型フライホールの研究開発
柳沼修太,増澤徹,長真啓,柴建次,巽英介,西村隆
第28回ライフサポート学会フロンティア講演会, 2019年03月 - 冠動脈バイパス手術における血管接合支援デバイスの研究開発
羽根田洋輔,増澤徹,長真啓,尾関和秀,岸田晶夫,巽英介
第28回ライフサポート学会フロンティア講演会, 2019年03月 - 冠動脈バイパス手術のための血管吻合デバイスの開発
吉田尚記,増澤徹,長真啓,尾関和秀,岸田晶夫,巽英介
第28回ライフサポート学会フロンティア講演会, 2019年03月 - 血液Ht変化に伴う粘度変化が磁気浮上インペラ非制御位置計測による血液遠心ポンプ流量推定精度に及ぼす影響
信太宗也,増澤徹,長真啓
第47回人工心臓と補助循環懇話会学術集会, 2019年02月 - 超小型磁気浮上モータを用いた次世代型遠心連続流式小児用人工心臓の血液循環性能評価,
長真啓,増澤徹,織原涼雅,築谷朋典,巽英介
第47回人工心臓と補助循環懇話会学術集会, 2019年02月 - 血液遠心ポンプ拍出流量推定手法確立のための磁気浮上インペラ流体評価
信太宗也,増澤徹,長真啓
第31回バイオエンジニアリング講演会, 2018年12月 - 磁気浮上インペラ偏心位置を用いた新しい血液遠心ポンプ流量推定手法確立のための流路内圧不平衡場解析
信太宗也,増澤徹,長真啓
日本生体医工学会関東支部若手研究者発表会2018, 2018年12月 - 小児心不全治療のための超小型な磁気浮上型補助人工心臓の研究開発
長真啓; 増澤徹; 織原涼雅; 巽英介
第56回日本人工臓器学会大会, 2018年11月 - 高せん断流れ場におけるせん断応力と接液面の表面粗さが溶血に及ぼす影響
安武勇貴; 長真啓; 丸山修; 西田正浩; 増澤徹
第56回日本人工臓器学会大会, 2018年11月 - Dynamic movement of the magnetically levitated impeller during pulsatile operation
Toru Masuzawa; Shuya Shida; Masahiro Osa; Takashi Nishimura; Eisuke Tatsumi
26th ISMCS2018, 2018年10月 - Next generation Ultra-Compact centrifugal pediatric VAD using maglev motor with Improved design to enhance energy efficiency
Masahiro Osa; Toru Masuzawa; Ryoga Orihara; Eisuke Tatsumi
26th ISMCS2018, 2018年10月 - Novel flow rate estimation method of a centrifugal blood pump using passive stabilization dynamics of magnetically levitated impeller
Shuya Shida; Toru Masuzawa; Masahiro Osa
26th ISMCS2018, 2018年10月 - Next generation Ultra-Compact centrifugal pediatric VAD using maglev motor with,Improved design to enhance energy efficiency
Masahiro Osa; Toru Masuzawa; Ryoga Orihara; Eisuke Tatsumi
26th ISMCS2018, 2018年10月 - 小児用人工心臓のための超小型磁気浮上モータの改良
織原涼雅; 増澤徹; 長真啓; 巽英介
第27回MAGDAコンファレンス,in Katusshika, 2018年10月 - 血液遠心ポンプ拍出流量推定のための磁気浮上インペラふれ回り運動解析
信太宗也,増澤徹,長真啓,大野康平,西村隆、許俊鋭,巽英介
LIFE2018, 2018年09月 - 複合低エネルギ冠動脈バイパス接合デバイスの開発
羽根田洋輔,増澤徹,長真啓,尾関和秀,岸田晶夫,片桐伸将,巽英介
LIFE2018, 2018年09月 - 磁気浮上式血液ポンプ内インペラ径方向受動安定ダイナミクスの血液量計測への応用
信太宗也,増澤徹; 長真啓
第57回日本生体医工学会大会, 2018年06月 - 全置換型磁気浮上人工心臓の浮上インペラの非制御軸の振動抑制
牧田丈靖,増澤徹,長真啓,Daniel L Timms
第30回「電磁力関連のダイナミクス」シンポジウム, 2018年05月 - 心拍同期型体外設置磁気浮上血液ポンプの研究開発
佐藤遼太; 増澤徹; 長真啓; 西村隆; 許俊鋭; 巽英介
第27回ライフサポート学会フロンティア講演会, 2018年03月 - 全置換型磁気浮上人工心臓の径方向受動安定性の向上
牧田丈靖; 増澤徹; 長真啓; Daniel L Timms
第27回ライフサポート学会フロンティア講演会, 2018年03月 - 人工心臓のためのホモポーラ型磁気浮上モータの構造検討
上田優人; 増澤徹; 長真啓; 小泉綾香
第27回ライフサポート学会フロンティア講演会, 2018年03月 - 高せん断流れ場における表面粗さと溶血に関する研究
安武勇貴; 増澤徹; 長真啓; 丸山修
第27回ライフサポート学会フロンティア講演会, 2018年03月 - これからのMCSデバイス開発
増澤徹
第46回人工心臓と補助循環懇話会学術集会, 2018年02月 - 磁気浮上式血液ポンプ内インペラ受動安定位置計測による血流量推定
信太宗也; 増澤徹; 長真啓; 佐藤遼太
第46回人工心臓と補助循環懇話会学術集会, 2018年02月 - インペラ変位による流体力増大を考慮した磁気浮上遠心血液ポンプ内ボリュート形状の検討
信太宗也; 増澤徹; 長真啓
第30回バイオエンジニアリング講演会, 2017年12月 - 全置換型磁気浮上人工心臓への反発型永久磁石磁気軸受の組み込み
牧田丈靖,増澤徹,國府田芳彰,長真啓,Daniel L Timms
第26回MAGDAコンファレンス in 金沢, 2017年10月 - 人工心臓への適用を目的とした4軸制御型磁気軸受の開発
小泉綾香,増澤徹,長真啓
第26回MAGDAコンファレンス in 金沢, 2017年10月 - 心拍同期型磁気浮上体外循環血液ポンプの径方向安定性評価
佐藤遼太,増澤徹,長真啓,大野康平,西村隆,許俊鋭
第26回MAGDAコンファレンス in 金沢, 2017年10月 - Effects of eccentrically whirling motion of a Magnetically levitated impeller on blood damage potential in a centrifugal blood pump
Shuya Shida; Toru Masuzawa; Masahiro Osa
2017 The International society for mechanical circulatory support (ISMCS), 2017年10月 - Performance evaluation of a magnetically levitated centrifugal pediatric VAD and motor design optimization for improvement of a maglev motor
Masahiro Osa; Toru Masuzawa; Ryoga Orihara; Eisuke Tatsumi
2017 The International society for mechanical circulatory support (ISMCS), 2017年10月 - 体外循環磁気浮上血液ポンプにおける浮上回転インペラ不釣り合いの径方向変位への影響
大野康平,増澤徹,長真啓,佐藤遼太,西村隆,許俊鋭
LIFE2017, 2017年09月 - 補助人工心臓のための4軸制御型磁気軸受の開発-3次元静磁場解析による軸受形状検討-
小泉綾香,増澤徹,長真啓
LIFE2017, 2017年09月 - 複合低エネルギを用いた冠動脈バイパス手術支援デバイスの開発-吻合時温度変化の検討-
羽根田洋輔,増澤徹,長真啓,尾関和秀,岸田晶夫
LIFE2017, 2017年09月 - Compact maglev motor with full DOF active control for miniaturized rotary blood pumps
Masahiro Osa; Toru Masuzawa; Ryoga Orihara; Eisuke Tatsumi
The 11th International Symposium on Linear Drives for Induatry Applications(LDIA2017), 2017年09月 - 反発型永久磁石磁気軸受による磁気浮上全人工心臓の安定化
牧田丈靖,増澤徹,長真啓,國府田芳彰,Daniel Timms
第55回日本人工臓器学会大会, 2017年09月 - 磁気浮上型体外循環血液ポンプの血液適合性向上のための浮上インペラ振れ回り運動解析
佐藤遼太,増澤徹,長真啓,信太宗也,大野康平,西村隆,許俊鋭
第55回日本人工臓器学会大会, 2017年09月 - 小型5軸制御磁気浮上モータを用いた小児用人工心臓のポンプ性能評価
織原涼雅,増澤徹,長真啓,巽英介
第55回日本人工臓器学会大会, 2017年09月 - 乳児・小児用磁気浮上補助人工心臓の開発
増澤徹,長真啓,巽英介
第55回日本人工臓器学会大会, 2017年09月 - 磁気浮上型全人工心臓の流量バランス制御に関する研究
牧田丈靖,増澤徹,長真啓,Daniel L Timms
第25回茨城講演会, 2017年08月 - 磁気支持安定性向上を目指した三次元磁場解析による小児用人工心臓用5軸制御磁気浮上モータの構造検討
織原涼雅,増澤徹,長真啓,巽英介
第25回茨城講演会, 2017年08月 - 磁気浮上型血液ポンプ内浮上インペラの羽根枚数が径方向変位に与える影響
大野康平,増澤徹,長真啓,佐藤遼太,西村隆,許俊鋭
第25回茨城講演会, 2017年08月 - 複合低エネルギを用いた冠動脈バイパス手術支援デバイスの開発-血管装着部の変更・加圧機構の改良-
羽根田洋輔,増澤徹,長真啓,尾関和秀,岸田晶夫
第25回茨城講演会, 2017年08月 - 5軸制御磁気浮上モータを用いた遠心式小児用人工心臓の開発
長真啓,増澤徹,斎藤拓也,巽英介
第29回「電磁力関連のダイナミクス」シンポジウム, 2017年05月 - 薄小型補助人工心臓用セルフベアリングモータの改良
村上倫子,増澤徹,小沼弘幸,西村隆,許俊鋭
第29回「電磁力関連のダイナミクス」シンポジウム, 2017年05月 - 磁気浮上遠心血液ポンプ設計のためのインペラ変位を考慮した数値流体解析
信太宗也,増澤徹,長真啓
第56回日本生体医工学会大会, 2017年05月 - 全置換型人工心臓の高度化に関する研究
國府田芳彰,増澤徹,長真啓,牧田丈靖,Daniel L Timms
第26回ライフサポート学会フロンティア講演会, 2017年03月 - 心臓治療を目的とした心拍同期型体外循環磁気浮上血液ポンプの研究開発
大野康平,増澤徹,長真啓,佐藤遼太,西村隆,許俊鋭
第26回ライフサポート学会フロンティア講演会, 2017年03月 - 複合低エネルギーを用いた冠動脈バイパス手術支援デバイスの研究開発
羽根田洋輔,増澤徹,尾関和秀,岸田晶夫,樋上哲哉
第26回ライフサポート学会フロンティア講演会, 2017年03月 - 作動流体粘度が磁気浮上補助人工心臓のポンプ・浮上性能に与える影響
村上倫子,増澤徹,小沼弘幸,西村隆,許俊鋭
第26回ライフサポート学会フロンティア講演会, 2017年03月 - 全置換型磁気浮上人工心臓の流量バランス制御に関する研究
牧田丈靖,増澤徹,長真啓,國府田芳彰,Daniel L Timms
第26回ライフサポート学会フロンティア講演会, 2017年03月 - 小児用人工心臓のための小型5軸制御磁気浮上モータの改良
織原涼雅,長真啓,増澤徹,斎藤拓也,巽英介
第26回ライフサポート学会フロンティア講演会, 2017年03月 - 磁気浮上型小児用補助人工心臓の研究開発
長真啓,増澤徹,斎藤卓也,巽英介
第45回人工心臓と補助循環懇話会学術集会, 2017年02月 - 磁気浮上血液ポンプのマグネットカプリング機構の設計
小泉綾香; 増澤徹; 國府田芳彰; 長真啓
第29回バイオエンジニアリング講演会, 2017年01月 - 磁気浮上型全人工心臓の課題
増澤徹,Daniel Timms
第54回日本人工臓器学会大会, 2016年11月, [招待有り] - 薄小型補助人工心臓のための径方向2軸制御型磁気浮上カスケードポンプの開発
辺 保昭; 増澤 徹; 村上 倫子; 小沼 弘幸,西村 隆,許 俊鋭
第25回MAGDAコンファレンス, 2016年11月 - 全置換型磁気浮上人工心臓のための反発型磁気軸受の検討
國府田 芳彰; 増澤 徹; 長 真啓; Daniel L TIMMS
第25回MAGDAコンファレンス, 2016年11月 - 超小型磁気浮上式小児用人工心臓の開発
斎藤拓也; 増澤徹; 長真啓; 巽英介
第25回MAGDAコンファレンス, 2016年11月 - Miniaturization of pediatric ventricular assist device with a double stator maglev motor
Takuya Saito; Toru Masuzawa; Masahiro Osa; Eisuke Tatsumi
24th Congress of the International Society for Rotary Blood Pumps, 2016年09月 - Performance enhancement of magliv ventricular assist device for mild heart disease patients
Yasuaki Watanabe; Toru Masuzawa; Michiko Murakami; Hiroyuki Onuma; Takashi Nishimura; Shunei Kyo
24th Congress of the International Society for Rotary Blood Pumps, 2016年09月 - Improvement in a next generation maglev centrifugal pediatric VAD
Masahiro Osa; Toru Masuzawa; Takuya Saito; Eisuke Tatsumi
24th Congress of the International Society for Rotary Blood Pumps, 2016年09月 - Magnetically levitated blood pump for extracorporeal circulation driven to synchronize with heart beat
Ryota Sato; Toru Masuzawa; Masahiro Osa; Takashi Nishimura; Shunei Kyo; Noritsugu Naito; Eisuke Tatsumi
24th Congress of the International Society for Rotary Blood Pumps, 2016年09月 - Maglev motor optimization for single rotating actuator total artificial heart
Yoshiaki Koda; Toru Masuzawa; Masahiro Osa; Daniel Lee Timms
24th Congress of the International Society for Rotary Blood Pumps, 2016年09月 - The investigation of hydrodynamic effect of the 3D micro-geometrical structures on physical adhesion phenomena of thrombus foemation
Akiko Oota; Toru Masuzawa; Kazuaki Nagayama
24th Congress of the International Society for Rotary Blood Pumps, 2016年09月 - 全置換型人工心臓用磁気浮上モータの改良
國府田芳彰,増澤徹,長真啓,Timms Daniel
LIFE2016, 2016年09月 - Effect of pulsatile operation on a maglev centrifugal blood pump
Toru Masuzawa
2016 Annual Conference of the Asia-Pacific Society for Artificial Organs, 2016年08月 - 心臓治療を目的とした磁気浮上型体外循環血液ポンプの研究開発
佐藤遼太,増澤徹,長真啓,西村隆,許俊鋭
第24回茨城講演会, 2016年08月 - 複合低エネルギ生体組織接合技術における生体組織構造変化の可視化
小泉綾香,増澤徹,長真啓,尾関和秀,岸田晶夫
第24回茨城講演会, 2016年08月 - Magnetic levitation performance of miniaturized magnetically levitated motor with 5-DOF active control
Masahiro Osa; Toru Masuzawa; Takuya Saito; Eisuke Tatsumi
15th International symposium on magnetic bearings, 2016年08月 - Magnetic Levitation Performance of Miniaturized Magnetically Levitated Motor with 5-DOF Active Control
Masahiro OSA; Toru MASUZAWA; Takuya SAITO; Eisuke TATSUMI
15th International Symposium on Magnetic Bearings, 2016年08月 - Development of radial type self-bearing motor for small centrifugal blood pump
Hiroyuki ONUMA; Toru MASUZAWA; Michiko MURAKAMI
15th International Symposium on Magnetic Bearings, 2016年08月 - The effect of 3-dimential micro-geometrical structures of bio-material surface on flow and adhesion phase in thrombus cascade
Toru Masuzawa
ASAIO 62nd Annual Conference, 2016年06月 - 小児用人工心臓用5軸制御磁気浮上モータのセンサレスモータ制御
長真啓; 増澤徹; 斎藤拓也; 巽英介
第28回「電磁力関連のダイナミクス」シンポジウム, 2016年05月 - 薄小型磁気浮上補助人工心臓の実用化に向けた改良
渡辺保昭; 増澤徹; 村上倫子; 小沼弘幸; 西村隆; 許俊鋭
第55回日本生体医工学会大会, 2016年04月 - レオメータを使用したせん断流れ場における血液接触面の表面粗さと溶血量の関係
中嶋翔太; 丸山修; 西田正浩; 足立吉數; 長真啓; 増澤徹
第55回日本生体医工学会大会, 2016年04月 - 人工心臓技術の現況と今後の展望
増澤徹,長真啓,柴建次,巽英介,西村隆,許俊鋭,Daniel Timms
日本医工学治療学会第32回学術大会, 2016年03月, [招待有り] - 複合低エネルギ生体組織接合技術の研究開発-FIB-SEMによる生体組織接合部の観察-
小泉綾香; 増澤徹; 長真啓; 尾関和秀; 岸田晶夫
ライフサポート学会第25回フロンティア講演会, 2016年03月 - 心拍同期型磁気浮上血液ポンプにおける受動安定性向上のための検討
下堀拓己; 増澤徹; 長真啓; 西村隆; 許俊鋭
ライフサポート学会第25回フロンティア講演会, 2016年03月 - 磁気浮上型体外循環血液ポンプの拍動運動における流体力推定
佐藤遼太; 増澤徹; 長真啓; 下堀拓己; 西村隆; 許俊鋭
ライフサポート学会第25回フロンティア講演会, 2016年03月 - 連続流式小児用磁気浮上心臓の研究開発
長真啓; 増澤徹; 斎藤拓也; 巽英介
第44回人工心臓と補助循環懇話会学術集会, 2016年03月 - 磁気浮上人工心臓の制御
増澤徹; 西村隆; 許俊鋭; 巽英介; Daniel Timms
第44回人工心臓と補助循環懇話会学術集会, 2016年03月 - 急性心不全適用を目指した体外循環磁気浮上ポンプの開発
増澤徹; 下堀拓己; 内藤啓嗣; 巽英介; 西村隆; 許俊鋭
日本定常流ポンプ研究会2015, 2015年11月 - 次世代型磁気浮上式小児用補助人工心臓の開発現状
長真啓; 増澤徹; 巽英介
第53回日本人工臓器学会大会, 2015年11月 - 薄小型磁気浮上補助人工心臓における非制御軸方向の振動と流体力
村上倫子; 増澤徹; 小沼弘幸; 西村隆; 許俊鋭
第53回日本人工臓器学会大会, 2015年11月 - 循環系シミュレータの冠循環模擬評価
黒崎亘; 増澤徹
第53回日本人工臓器学会大会, 2015年11月 - 連続流型磁気浮上全人工心臓の開発
箕輪純承; 増澤徹; 長真啓; 國府田芳彰
第53回日本人工臓器学会大会, 2015年11月 - 人工材料上の表面粗さ周囲に発生する流れと血栓形成に関する基礎研究~幾何学構造周囲流れの予測と成分付着の関係~
太田晶子; 増澤徹; 柴田隆行
第53回日本人工臓器学会大会, 2015年11月 - センサレスモータ制御を用いた磁気浮上血液ポンプの回転数変調
長真啓; 増澤徹; 下堀拓己; 西村隆; 許俊鋭
第58回自動制御連合講演会, 2015年11月 - ラジアル型セルフベアリングモータにおける受動安定性の簡易推定式の検討
小沼弘幸; 増澤徹; 村上倫子
第24回MAGDAコンファレンス, 2015年11月 - 磁気浮上型人工心臓のための永久磁石磁気カップリングの基礎検討
國府田芳彰; 増澤徹; 長真啓; Kieran Hunter
第24回MAGDAコンファレンス, 2015年11月 - 心拍同期型磁気浮上血液ポンプにおける受動安定軸の浮上安定性評価
下堀拓己; 増澤徹; 西村隆; 許俊鋭
第24回MAGDAコンファレンス, 2015年11月 - Magnetically suspended total artificial heart with a single actuator
Toru Masuzawa
APSAO2015, 2015年10月 - A double side stator type axial self-bearing motor development for the left ventricular assist device
Nobuyuki Kurita; Takeo Ishikawa; Naoki Saito; Toru Masuzawa
The 17th International Symposium on Applied Electromagnetics and Mechanics, 2015年09月 - Ministurizing 5-DOF fully controlled axial gap maglev motor for pediatric ventricular assist devices
Masahiro Osa; Toru Masuzawa; Naoki Omori; Eisuke Tatsumi
The 17th International Symposium on Applied Electromagnetics and Mechanics, 2015年09月 - 小児用人工心臓用5軸制御磁気浮上モータの小型化
斎藤拓也; 増澤徹; 長真啓; 巽英介
第23回茨城講演会, 2015年08月 - ホモポーラ型ハイブリッド5軸制御セルフベアリングモータに関する研究
鈴木力; 松田健一; 岡田養二; 近藤良; 増澤徹
第23回茨城講演会, 2015年08月 - IPM型5軸制御セルフベアリングモータに関する研究
徳井春彦; 松田健一; 近藤良; 増澤徹
第23回茨城講演会, 2015年08月 - コンシクエントポール型5軸制御セルフベアリングモータの基本特性解析
原田誠; 松田健一; 近藤良; 増澤徹
第23回茨城講演会, 2015年08月 - 二重円筒型レオメータによる人工材料溶血定量評価
中嶋翔太; 丸山修; 西田正浩; 足立吉數; 長真啓; 増澤徹
第23回茨城講演会, 2015年08月 - 全置換型磁気浮上人工心臓の研究開発-エネルギ伝送技術を用いた径方向変位抑制機構-
國府田芳彰; 増澤徹; 箕輪純承; 長真啓; 柴建次; Daniel L Timms
第23回茨城講演会, 2015年08月 - 数値流体解析による薄小型磁気浮上補助人工心臓用カスケードポンプの改良
渡辺保昭; 増澤徹; 村上倫子; 小沼弘幸; 西村隆; 許俊鋭
第23回茨城講演会, 2015年08月 - スパッタリング法による水熱結晶化マグネシウム含有HA薄膜の溶解性及び密着性評価
第23回茨城講演会, 2015年08月 - 磁性粒子を用いた磁気励振細胞刺激機構の開発
西村佳織; 増澤徹; 長真啓; 林照剛; 岸田晶夫
第27回「電磁力関連のダイナミクス」シンポジウム, 2015年05月 - 小児用人工心臓のための5軸制御磁気浮上モータの回転速度センサレス制御
長真啓; 増澤徹; 大森直樹; 巽英介
第27回「電磁力関連のダイナミクス」シンポジウム, 2015年05月 - Mechanical circulatory supportのための磁気浮上血液ポンプ
増澤徹
第54回生体医工学会大会, 2015年05月 - 人工材料表面上での微小流れと抗血栓性に関する研究
山口直紀
関東学生会第54回学生員卒業研究発表講演会, 2015年03月 - 複合低エネルギ生体組織接合技術の開発研究-コラーゲン変性可視化による至適接合条件の検討-
諏訪陽祐; 増澤徹; 長真啓; 尾関和秀; 岸田晶夫; 樋上哲哉
第24回ライフサポート学会フロンティア講演会, 2015年03月 - 小児用磁気浮上人工心臓の小型化設計
斎藤拓也; 増澤徹; 長真啓; 大森直樹; 巽英介
第24回ライフサポート学会フロンティア講演会, 2015年03月 - 全置換型人工心臓のための磁気浮上モータの改良
國府田芳彰; 増澤徹; 長真啓; 箕輪純承; Daniel L Timms
第24回ライフサポート学会フロンティア講演会, 2015年03月 - 薄小型磁気浮上補助人工心臓用カスケードポンプの改良
渡辺保昭; 増澤徹; 村上倫子; 吉田翔一; 小沼弘幸; 西村隆; 許俊鋭
第24回ライフサポート学会フロンティア講演会, 2015年03月 - 人工心臓材料表面性状と血液適合性に関する研究-人工材料表面粗さが溶血に及ぼす影響の検討-
中嶋翔太; 丸山修; 西田正浩; 足立吉數; 増澤徹
第24回ライフサポート学会フロンティア講演会, 2015年03月 - 乳幼児、小児用補助人工心臓のための磁気浮上モータの小型化
長真啓; 増澤徹; 大森直樹; 巽英介
第43回人工心臓と補助循環懇話会学術集会, 2015年02月 - 磁気浮上型心臓治療用血液ポンプへのセンサレスモータ制御の適用
大森直樹; 増澤徹; 長真啓; 下堀拓己; 西村隆; 許俊鋭
第23回MAGDAコンファレンスin 高松, 2014年12月 - 薄小型磁気浮上補助心臓における浮上インペラの受動安定軸の変動計測
吉田翔一; 増澤徹; 村上倫子; 小沼弘幸; 西村隆; 許俊鋭
第23回MAGDAコンファレンスin 高松, 2014年12月 - ホモポーラ型ハイブリット5軸制御セルフベアリングモータの開発
加藤正寛; 松田健一; 岡田養二; 近藤良; 増澤徹
第23回MAGDAコンファレンスin 高松, 2014年12月 - The relationship between the thrombogenicity and the generated flow around 3-dimensional micro geometrical structures on the bio-material –Investigation of micro flow-
Ota-Ishigaki A; Masuzawa T; Shibata T; Kawashima T; Maruyama O
The 10th International Student Conference at Ibaraki University, 2014年11月 - Cardiovascular circulation simulator to evaluate ventricular assist effect
Kurosaki W; Masuzawa T
The 10th International Student Conference at Ibaraki University, 2014年11月 - 全置換型磁気浮上人工心臓への反発型永久磁石磁気軸受の組み込み
牧田丈靖,増澤徹,國府田芳彰,長真啓,Daniel L Timms
第26回MAGDAコンファレンス in 金沢, 2014年10月 - 重症化予防のための薄小型磁気浮上補助人工心臓
増澤徹; 村上倫子; 吉田翔一; 長真啓; 小沼弘幸; 許俊鋭; 西村隆; 柴建次
第52回日本人工臓器学会大会, 2014年10月 - 冠循環模擬を付加した循環系シミュレータの性能評価
黒崎亘; 増澤徹; 箕輪純承
第52回日本人工臓器学会大会, 2014年10月 - 5軸制御磁気浮上モータを用いた乳幼児、小児用補助人工心臓の開発
長真啓; 増澤徹; 大森直樹; 巽英介
第52回日本人工臓器学会大会, 2014年10月 - 全置換型磁気浮上人工心臓:BiVACORとIBHeart
増澤徹; Daniel Timms; Shaun Gregory
日本定常流ポンプ研究会2014, 2014年10月 - 複合低エネルギ生体組織接合のおける生体組織含水率と接合強度の関係
諏訪陽祐; 増澤徹; 長真啓; 尾関和秀; 岸田晶夫; 樋上哲哉
生活生命支援医療福祉工学系学会連合大会, 2014年09月 - 薄小型補助人工心臓磁気浮上インペラの非制御軸挙動
吉田翔一; 増澤徹; 村上倫子; 長真啓; 小沼弘幸; 西村隆; 許俊鋭
生活生命支援医療福祉工学系学会連合大会, 2014年09月 - Pediatric VAD with five degrees of freedom control maglev motor
Toru Masuzawa
the 41st Annual ESAO Congress, 2014年09月 - スパッタリング法によるマグネシウム置換HA薄膜の作製とマグネシウム置換量の評価
但野ちなみ; 尾関和秀; 増澤徹; 青木秀希
第22回茨城講演会, 2014年09月 - ケイ酸塩またはHA粉末を用いた放射性物質吸着とケイ酸塩/HA複合体作成方法の検討
大和田詠里; 尾関和秀; 増澤徹; 青木秀希
第22回茨城講演会, 2014年09月 - 複合低エネルギ生体組織接合技術を利用した冠動脈バイパス手術支援デバイスの研究開発
荒昌幸; 増澤徹; 長真啓; 尾関和秀; 岸田晶夫; 樋上哲哉
第22回茨城講演会, 2014年09月 - 生体組織融着技術におけるステントの加熱手法の基礎的検討
豊田裕史; 田代翔子; 橋本一生; 柴建次; 岸田晶夫; 木村剛; 尾関和秀; 増澤徹
第22回茨城講演会, 2014年09月 - 急性心不全のための心拍同期型磁気浮上ポンプの研究開発
下堀拓己; 増澤徹; 長真啓; 西村隆; 許俊鋭
第22回茨城講演会, 2014年09月 - 冠循環模擬機構を有する循環系シミュレータの開発
箕輪純承; 増澤徹; 黒崎亘; 長真啓
第22回茨城講演会, 2014年09月 - Magnetically Suspended Motor System for Artificial Hearts and Blood Pumps
Toru Masuzawa
14th International Symposium on Magnetic Bearings, 2014年08月 - Radial position Active Control of Double Stator Axial Gap Self-Bearing Motor for Peadiatric VAD
Masahiro Osa; Toru Masuzawa; Naoki Omori; Eisuke Tatsumi
14th International Symposium on Magnetic Bearings, 2014年08月 - Thin Maglev Ventricular Assist Device with Radial Type Self-Bearing Motor
Michiko Murakami; Toru Masuzawa; Shoichi Yoshida; Hiroyuki Onuma; Takashi Nishimura; Syunei Kyo
14th International Symposium on Magnetic Bearings, 2014年08月 - Evaluation of magnetic Suspension Characteristics and Levitation Performance of a centrifugal Blood pump Using Radial Type Self-Bearing Motor
Hiroyuki Onuma; Toru Masuzawa
14th International Symposium on Magnetic Bearings, 2014年08月 - Optimization design of magnetically suspended system for the BIVACOR total artificial heart
Kurita N; Timm D; Greatrex N; Kleinheyer M; Masuzawa T
14th International Symposium on Magnetic Bearings, 2014年08月 - Magnetically Suspended Artificial Heart
Toru Masuzawa
8th Asia-Pacific Symposium on Applied Electromagnetics and Mechanics, 2014年07月, [招待有り] - シングル磁気浮上モータを使用した全置換型人工心臓
増澤徹; ティムス ダニエル
第53回日本生体医工学会大会, 2014年06月 - 循環補助デバイスのための渦流(カスケード)ポンプ
増澤徹; 村上倫子
第53回日本生体医工学会大会, 2014年06月 - 小児用補助人工心臓のための小型磁気浮上モータの開発
大森直樹; 増澤徹; 長真啓; 巽英介
第26回「電磁力関連のダイナミクス」シンポジウム, 2014年05月 - 磁気ビーズを用いた磁気励振細胞刺激システム
増澤徹; 服部圭介; 林照剛; 木村剛; 岸田晶夫
第26回「電磁力関連のダイナミクス」シンポジウム, 2014年05月 - 全置換型磁気浮上人工心臓と流量バランス制御
山田悠; 増澤徹; Daniel L Timms
第26回「電磁力関連のダイナミクス」シンポジウム, 2014年05月 - 回転数周期的変動時の磁気浮上型血液ポンプの浮上安定性と溶血性能の検討
増澤徹; 山口聡史; 下堀拓己; 西村隆; 許俊鋭
第26回「電磁力関連のダイナミクス」シンポジウム, 2014年05月 - 新しい循環治療方法の評価を目指した循環系シミュレータの研究開発
箕輪純承; 増澤徹; 黒崎亘
関東学生会第53回学生員卒業研究発表講演会, 2014年03月 - 乳幼児, 小児に適用可能な磁気浮上補助人工心臓の開発
長真啓; 増澤徹; 大森直樹; 巽英介
第42回人工心臓と補助循環懇話会学術集会, 2014年03月 - 左右心流量バランス機能を有した全置換型磁気浮上人工心臓
山田悠; 増澤徹; ティムズダニエル
第42回人工心臓と補助循環懇話会学術集会, 2014年03月 - 薄型補助人工心臓の開発
村上倫子; 増澤徹; 小沼弘幸; 西村隆; 許俊鋭
第42回人工心臓と補助循環懇話会学術集会, 2014年03月 - 全置換型磁気浮上人工心臓と流量バランス制御の研究
山田悠; 増澤徹
第23回ライフサポート学会フロンティア講演会, 2014年02月 - 磁気浮上型心臓治療用血液ポンプのインペラの浮上安定性の検討
下堀拓己; 増澤徹; 山口聡史; 西村隆; 許俊鋭
第23回ライフサポート学会フロンティア講演会, 2014年02月 - 複合低エネルギ生体組織接合技術を利用した冠動脈バイパス手術支援デバイスの開発
荒昌幸; 増澤徹; 尾関和秀; 岸田晶夫; 樋上哲哉
第23回ライフサポート学会フロンティア講演会, 2014年02月 - 小児、乳児用人工心臓のための5軸制御磁気浮上モータ
長真啓; 増澤徹; 大森直樹; 巽英介
第23回ライフサポート学会フロンティア講演会, 2014年02月 - 薄型磁気浮上補助人工心臓における受動安定特性の検討
村上倫子; 増澤徹; 小沼弘幸; 西村隆; 許俊鋭
第22回MAGDAコンファレンスin宮崎, 2013年12月 - 12突極ラジアル型セルフベアリングモータの磁気支持特性の推定
小沼弘幸; 増澤徹
第22回MAGDAコンファレンスin宮崎, 2013年12月 - 磁気浮上型血液ポンプのセンサレスモータ制御
床井宏行; 増澤徹; 山口聡史; 西村隆; 許俊鋭
第22回MAGDAコンファレンスin宮崎, 2013年12月 - 小児用人工心臓のための小型5軸制御セルフベアリングモータ
長真啓; 増澤徹; 大森直樹; 巽英介
第22回MAGDAコンファレンスin宮崎, 2013年12月 - アウターロータ型5軸制御セルフベアリングモータに関する研究
松田健一; 平根龍也; 近藤良; 増澤徹
第22回MAGDAコンファレンスin宮崎, 2013年12月 - 生体組織融着技術を用いた血管吻合装置の開発-加圧バンドを用いた場合の融着強度評価-
橋本一生; 柴建次; 岸田晶夫; 尾関和秀; 増澤徹
リニアドライブ研究会, 2013年10月, 電気学会 - ゼロパワー制御を用いた磁気浮上全人工心臓の流量バランス制御
山田悠; 増澤徹; ティムズダニエル
リニアドライブ研究会, 2013年10月 - The thin maglev ventricular assist device for mild heart disease patients
Michiko Murakami; Toru Masuzawa; Hiroyuki Onuma; Takashi Nishimura; Syunei Kyo
21th ISRBP2013 YOKOHAMA, 2013年09月 - Development of the left ventricular assist device by use of the double side stator type axial magnetically levitated motor
Nobuyuki Kurita; Takeo Ishikawa; Hirohumi Takada; Toru Masuzawa
21th ISRBP2013 YOKOHAMA, 2013年09月 - Hemolysis characteristics of maglev blood pump operated in the pulsatile mode
Satoshi Yamaguchi; Toru Masuzawa; Takashi Nishimura; Shunei Kyo
21th ISRBP2013YOKOHAMA, 2013年09月 - Performance improvement of two-DOF control self-bearing motor for maglev centrifugal blood pump
Hiroyuki Onuma; Toru Masuzawa
21th ISRBP2013 YOKOHAMA, 2013年09月 - Characterizing the magnetic motor-bearing of a rotary TAH to improve pressuresensitivity
Masahiro Osa; Toru Masuzawa; Hiroyuki Tokoi; Nobuyuki Kurita; Nicholas Greatrex; Daniel Timms
21th ISRBP2013 YOKOHAMA, 2013年09月 - Magnetically suspended total artificial heart with a single maglev motor
Yu Yamada; Toru Masuzawa; Daniel Lee Timms
21th ISRBP2013YOKOHAMA, 2013年09月 - A small thin maglev ventoricular assist device for mild heart disease patients
Toru Masuzawa; Michiko Murakami; Yusuke Sakata; Shoichi Yoshida; Hiroyuki Onuma; Takashi Nisimura; Syunei Kyo
5th Congress of the International Federation for Artificial Organs (IFAO2013), 2013年09月 - Observation of collagens’ microscopic structure change to investigate the adhesion mechanism combined low level energies
Yosuke Suwa; Toru Masuzawa; Kwangwoo Nam; Tsuyoshi Kimura; Akio Kishida
5th Congress of the International Federation for Artificial Organs (IFAO2013), 2013年09月 - The mechanical cell stimulator using alternative magnetic field eith magnetic beads attached on the cell
Keisuke Hattori; Toru Masuzawa; Terutake Hayashi
5th Congress of the International Federation for Artificial Organs (IFAO2013), 2013年09月 - Motor performance of magnetically levitated paediatric VAD
Naoki Omori; Toru Masuzawza; Masahiro Osa; Eisuke Tatsumi
5th Congress of the International Federation for Artificial Organs (IFAO2013), 2013年09月 - Magnetically suspended total artificial heart with a single actuator
T.Masuzawa; N.Nishimura; D.L.Timms
XL ESAO Annual Congress, 2013年09月 - 薄型磁気浮上補助人工心臓のための動圧スラスト軸受
吉田翔一; 増澤徹; 村上倫子; 坂田祐介; 小沼弘幸; 西村隆; 許俊鋭
第21回茨城講演会, 2013年09月 - 小児用人工心臓への応用を目指した5軸制御型小型磁気浮上モータの開発
大森直樹; 増澤徹; 長真啓; 巽英介
第21回茨城講演会, 2013年09月 - コンシクエントポール型セルフベアリングモータの基本特性解析
加藤正寛; 松田健一; 岡田養二; 近藤良; 増澤徹
第21回茨城講演会, 2013年09月 - 生体組織融着技術を用いたステントの位置ずれ防止-小型コイルによるステントの誘導加熱と引張強度評価-
田代翔子; 橋本一生; 柴建次; 岸田晶夫; 尾関和秀; 増澤徹
第21回茨城講演会, 2013年09月 - 複合低エネルギ生体組織接合に関する研究-加圧熱によるコラーゲンフィブリルの幾何学的形状変化-
諏訪陽祐; 増澤徹; 南広祐; 木村剛; 岸田晶夫
第21回茨城講演会, 2013年09月 - アパタイトおよびケイ酸塩を用いた放射性物質除去に関する研究
大和田詠里; 尾関和秀; 増澤徹; 青木秀希
生活生命支援医療福祉工学系学会連合大会, 2013年09月 - 生体組織融着技術を用いた血管吻合装置の開発-ステントの加熱と融着強度の評価-
橋本一生; 田代翔子; 柴建次; 岸田晶夫; 尾関和秀; 増澤徹
生活生命支援医療福祉工学系学会連合大会, 2013年09月 - せん断流れ場における血液接触面の表面粗さが溶血量増加に及ぼす定量評価-せん断応力発生の関与について-
丸山修; 工藤大樹; 西田正浩; 山根隆志; 松田健一; 足立吉數; 増澤徹
生活生命支援医療福祉工学系学会連合大会, 2013年09月 - 複合低エネルギ生体組織接合に関する研究-加圧機によるコラーゲンフィブリルの幾何学的形状変化の検討-
諏訪陽祐; 増澤徹; 南広祐; 木村剛; 岸田晶夫
生活生命支援医療福祉工学系学会連合大会, 2013年09月 - 磁気ビーズを用いた細胞振動刺激装置及びナノ振動検出装置の研究開発
服部圭介; 増澤徹; 林照剛
生活生命支援医療福祉工学系学会連合大会, 2013年09月 - 小児用人工心臓のための小型磁気浮上モータにおけるロータ永久磁石形状の検討
大森直樹; 増澤徹; 長真啓; 巽英介
生活生命支援医療福祉工学系学会連合大会, 2013年09月 - 全人工心臓用モータ小型化の検討
床井宏行; 増澤徹; Daniel L Timms
第25回「電磁力関連のダイナミクス」シンポジウム, 2013年05月 - 心機能回復のための磁気浮上型血液ポンプの動特性に関する検討
山口聡史; 増澤徹; 大森正芳; 前田裕之; 西村隆; 許俊鋭
第25回「電磁力関連のダイナミクス」シンポジウム, 2013年05月 - 薄型磁気浮上摩擦血液ポンプにおける非制御軸の安定性への流体力の影響
村上倫子; 増澤徹; 坂田佑介; 小沼弘幸; 西村隆; 許俊鋭
第25回「電磁力関連のダイナミクス」シンポジウム, 2013年05月 - ストロンチウム固溶ハイドロキシアパタイト薄膜の作製と骨芽細胞による評価
星野智大; 尾関和秀; 後藤哲哉; 増澤徹; 青木秀希
第22回ライフサポート学会フロンティア講演会, 2013年03月 - カテーテル搭載用小型コイルを用いた食道用ステントの誘導加熱-小型コイルの開発と評価-
田代翔子; 橋本一生; 柴建次; 岸田晶夫; 尾関和秀; 増澤徹
第22回ライフサポート学会フロンティア講演会, 2013年03月 - 複合低エネルギを用いた腹腔鏡手術用鉗子型接合デバイスの開発
中島彩; 青代敏行; 増澤徹; 尾関和秀; 岸田晶夫; 樋上哲哉
第22回ライフサポート学会フロンティア講演会, 2013年03月 - 複合低エネルギ接合を利用した人工心臓用脱血管の研究
佐々木悠祐; 青代敏行; 増澤徹; 尾関和秀; 岸田晶夫; 巽英介
第22回ライフサポート学会フロンティア講演会, 2013年03月 - 生体組織・金属接合のための電磁誘導加熱に関する研究
横須賀匠; 増澤徹; 橋本英子; 柴建次
第22回ライフサポート学会フロンティア講演会, 2013年03月 - 細胞振動印加装置及びナノ振動検出装置の研究開発
放生宏貴; 増澤徹; 服部圭介; 林照剛
第22回ライフサポート学会フロンティア講演会, 2013年03月 - 小型磁気浮上摩擦血液ポンプのための動圧軸受の研究開発,
吉田翔一; 増澤徹; 村上倫子; 坂田 祐介; 小沼弘幸; 西村隆; 許俊鋭
第22回ライフサポート学会フロンティア講演会, 2013年03月 - 小児用磁気浮上人工心臓の研究開発
大森直樹; 増澤徹; 長真啓; 巽英介
第22回ライフサポート学会フロンティア講演会, 2013年03月 - 人工材料表面の3次元マイクロドメイン幾何学構造と血液適合性に関する研究
古河翔多; 増澤徹; 太田晶子; 柴田隆行; 川島貴弘
第22回ライフサポート学会フロンティア講演会, 2013年03月 - 新しい治療デバイスと磁気浮上技術
増澤徹; 西村隆; 許俊鋭; 巽英介; TIMMS Daniel
第41回人工心臓と補助循環懇話会学術集会, 2013年02月 - BiVACOR-Implantable Rotary Total Artificial Heart
TIMMS Daniel; COHN William; PARNIS Steven; GREATREX Nicholas; KURITA Nobuyuki; MASUZAWA Toru
第41回人工心臓と補助循環懇話会学術集会, 2013年02月 - 乳児用人工心臓への応用を目指した5自由度制御型磁気浮上モータの開発
長真啓; 増澤徹; 巽英介
第41回人工心臓と補助循環懇話会学術集会, 2013年02月 - 薄型補助人工心臓に用いる2軸制御型磁気浮上ポンプの開発
村上倫子; 増澤徹; 小沼弘幸; 西村隆; 許俊鋭
第41回人工心臓と補助循環懇話会学術集会, 2013年02月 - 磁気浮上全人工心臓の流量バランス制御
太田晶子; 増澤徹; 西村宣彦; TIMMS Daniel
第41回人工心臓と補助循環懇話会学術集会, 2013年02月 - 小児用人工心臓のための小型磁気浮上モータの開発
長真啓、増澤徹、巽英介
第25回バイオエンジニアリング講演会, 2013年01月 - 小型補助人工心臓のためのハイブリッド軸受の開発
床井宏行、増澤徹、ニコラス グレイトレックス、ウーリッヒ スタインセイファー
第25回バイオエンジニアリング講演会, 2013年01月 - 循環系シミュレータにおける血管コンプライアンスと血圧波形との関係の検討
須田佳裕、増澤徹、黒崎亘
第25回バイオエンジニアリング講演会, 2013年01月 - 弾性ヒンジ型ナノ振動印加装置の研究開発
服部圭介、増澤徹、木村孝之、古山昭
第25回バイオエンジニアリング講演会, 2013年01月 - 磁気浮上型全人工心臓のCFD解析
太田晶子、増澤徹、西村宣彦、ティムスダニエル
第50回日本人工臓器学会大会, 2012年11月 - 複合低エネルギーを用いた組織接合法のin vivo評価
橋本英子、増澤徹、尾関和秀、丸岡寛明、青代敏行、樋上哲哉、舩本誠一、岸田晶夫、木村剛
第50回日本人工臓器学会大会, 2012年11月 - 乳児用人工心臓のための5自由度制御型磁気浮上モータ
長真啓、増澤徹、巽英介
第50回日本人工臓器学会大会, 2012年11月 - これからの定常流ポンプ研究開発 新しい循環器病治療方法への対応
36)増澤徹,西村隆,許俊鋭,巽英介,Daniel L Timms
日本定常流ポンプ研究会2012, 2012年11月, 日本定常流ポンプ研究会 - シングル磁気浮上モータ方式全人工心臓の開発
西村宣彦、増澤徹、Daniel L Timms
第21回MAGDAコンファレンス, 2012年11月 - IPM型5軸制御セルフベアリングモータのコギングトルク低減に関する研究
佐藤心平、松田健一、近藤良、増澤徹
第21回MAGDAコンファレンス, 2012年11月 - 薄型補助人工心臓のための2軸制御磁気浮上ポンプの開発
村上倫子、増澤徹、小沼弘幸、西村隆、許俊鋭
第21回MAGDAコンファレンス, 2012年11月 - スパッタリング法を用いたSr固溶HA薄膜の作製と骨芽細胞による評価
星野智大、尾関和秀、後藤哲哉、増澤徹、青木秀希
生活生命支援医療福祉工学系学会連合大会2012, 2012年11月 - せん断流れ場における血液接触材料の表面粗さが溶血量増加に及ぼす定量評価
丸山修、伊藤大輝、西田正浩、山根隆志、松田健一、足立吉數、増澤徹
生活生命支援医療福祉工学系学会連合大会2012, 2012年11月 - 磁気浮上全人工心臓の研究開発
西村宣彦、増澤徹、ダニエル・ティムス
生活生命支援医療福祉工学系学会連合大会2012, 2012年11月 - 磁気浮上全人工心臓のポンプ内部圧力分布解明のためのCFD解析
太田晶子、増澤徹、西村宣彦、ダニエル・ティムス
生活生命支援医療福祉工学系学会連合大会2012, 2012年11月 - 低エネルギ生体融着デバイスの開発-圧力測定機構の付加-
丸岡寛明、増澤徹、橋本英子、青代敏行、岸田晶夫、舩本誠一、樋上哲哉
生活生命支援医療福祉工学系学会連合大会2012, 2012年11月 - Novel Long Term Ventricular Assist Device for Mild Heart Disease Patients
Masuzawa T; Ukita K; Onuma H; Nishimura T; Kyo S
XXXIX Annual ESAO Congress, 2012年09月, ESAO - CFD Analysis for Maglev Total Artificial Heart
Akiko Ota; Toru Masuzawa; Nobuhiko Nishimura; Yusuke Sakata; Daniel L Timms
20th Congress of the International Society for Rotary Blood Pumps, 2012年09月, the International Society for Rotary Blood Pumps - Levitated Bearings Technology for RBPs: Challenge or Perspective?
Toru Masuzawa; Daniel L Timms
20th Congress of the International Society for Rotary Blood Pumps, 2012年09月, the International Society for Rotary Blood Pumps, [招待有り] - 新しい人工心臓装着支援技術に関する研究
床井宏行、増澤徹、橋本英子、尾関和秀、青代敏行、岸田晶夫、樋上哲哉、巽英介
第20回茨城講演会, 2012年08月 - 単一磁気浮上モータを用いた全置換型人工心臓の研究開発
坂田佑介、増澤徹、西村宣彦、Daniel L Timms
第20回茨城講演会, 2012年08月 - 心機能回復のための磁気浮上型血液ポンプの研究開発
山口聡史、増澤徹、山田悠、大森正芳、前田裕之、西村隆、許俊鋭
第20回茨城講演会, 2012年08月 - 小型・高性能アウターロータ型5軸制御セルフベアリングモータの開発
平根龍也、松田健一、近藤良、増澤徹
第20回茨城講演会, 2012年08月 - ホモポーラ型ハイブリッド5軸制御セルフベアリングモータの開発
玉置将也、松田健一、岡田養二、近藤良、増澤徹
第20回茨城講演会, 2012年08月 - スパッタリング法によるストロンチウム固溶HA薄膜の作製と物性評価
星野智大、尾関和秀、後藤哲哉、増澤徹、青木秀希
第20回茨城講演会, 2012年08月 - 磁性ビーズ細胞励振系およびナノ振動計測系の研究開発
服部圭介、増澤徹、長真啓、林照剛
第20回茨城講演会, 2012年08月 - 二重円筒型レオメーターを使用したせん断流れ場における表面粗さが溶血に与える影響
丸山修、伊藤大輝、西田正浩、山根隆志、松田健一、足立吉數、増澤徹
第20回茨城講演会, 2012年08月 - 5-DOF control double stator otor for paediatric ventricular assist device
Masahiro Osa; Toru Masuzawa; Eisuke Tatsumi
13th international Symposium on Magnetic Bearings(ISMB13), 2012年08月 - 人工心臓用ラジアル型磁気浮上モータのステータ突極形状の検討
小沼弘幸、増澤徹
第24回「電磁力関連のダイナミクス」シンポジウム, 2012年05月 - 新しい人工心臓装着支援装置に関する研究
床井宏行、増澤徹、青代敏行、橋本英子、尾関和秀、岸田晶夫、樋上哲哉、巽英介
第24回「電磁力関連のダイナミクス」シンポジウム, 2012年05月 - ホモポーラ型ハイブリッド5軸制御セルフベアリングモータの提案
松田健一、玉置将也、岡田養二、近藤良、増澤徹
第24回「電磁力関連のダイナミクス」シンポジウム, 2012年05月 - 災害と補助人工心臓在宅治療
増澤徹
第51回日本生体医工学会大会, 2012年05月 - 複合低エネルギを用いた鉗子型組織接合装置の開発
丸岡寛明、増澤徹、青代敏行、尾関和秀、木村剛、岸田晶夫、船本誠一、樋上哲哉
第51回日本生体医工学会大会, 2012年05月 - 小型磁気浮上摩擦血液ポンプの開発
浮田啓悟、増澤徹、小沼弘幸、西村隆、許俊鋭
第21回ライフサポート学会フロンティア講演会, 2012年03月, ライフサポート学会 - オンチップ細胞機能制御のための圧電駆動型マイクロ細胞培養デバイスの開発-器械的ナノ振動刺激の付与による細胞接着の評価-
山田侑平、梅垣彦希、川島貴弘、永井萌土、柴田隆行、増澤徹、木村剛、岸田晶夫
第21回ライフサポート学会フロンティア講演会, 2012年03月, ライフサポート学会 - 弾性損失発熱を利用した生体接着装置の開発
笠原康佑、南広祐、木村剛、清水繁、青代敏行、増澤徹、岸田晶夫
第21回ライフサポート学会フロンティア講演会, 2012年03月, ライフサポート学会 - 生体組織融着技術を用いた血管吻合装置の開発-加熱性能の評価-
橋本一生、柴建次、岸田晶夫、尾関和秀、増澤徹
第21回ライフサポート学会フロンティア講演会, 2012年03月, ライフサポート学会 - 磁気浮上モータを用いた全置換型人工心臓のポンプ性能
坂田佑介、増澤徹、西村宣彦、Daniel L Timms
第21回ライフサポート学会フロンティア講演会, 2012年03月, ライフサポート学会 - 心臓治療用血液ポンプのモータ効率化と溶血性能の検討
山口聡史、増澤徹、山田悠、大森正芳、前田裕之、西村隆、許俊鋭
第21回ライフサポート学会フロンティア講演会, 2012年03月, ライフサポート学会 - 磁気ビーズ細胞励振系およびナノ振動計測系の開発
服部圭介、増澤徹、長真啓、林照剛
第21回ライフサポート学会フロンティア講演会, 2012年03月, ライフサポート学会 - 心臓治療用磁気浮上血液ポンプの溶血性能評価
山田悠、増澤徹、大森正芳、前田裕之、西村隆、許俊鋭
第40回人工心臓と補助循環懇話会, 2012年02月 - 小型非接触摩擦血液ポンプの研究開発
浮田啓悟、増澤徹、小沼弘幸、西村隆、許俊鋭
第40回人工心臓と補助循環懇話会, 2012年02月 - 磁気浮上全人工心臓のポンプ性能
西村宣彦、増澤徹、ダニエルティムズ
第40回人工心臓と補助循環懇話会, 2012年02月 - 用途別に分化する磁気浮上型血液ポンプ
増澤徹、巽英介、西村隆、許俊鋭
第49回日本人工臓器学会大会, 2011年11月, 日本人工臓器学会 - 磁気浮上小型摩擦血液ポンプの研究開発
浮田啓悟、増澤徹、小沼弘幸、西村隆、許俊鋭
第49回日本人工臓器学会大会, 2011年11月, 日本人工臓器学会 - 動圧軸受血液ポンプのための傾き制御用磁気軸受の研究開発
須田佳裕、増澤徹、一ノ瀬高紀、ティムス ダニエル、ウーリッヒ スタインセイファー
第49回日本人工臓器学会大会, 2011年11月, 日本人工臓器学会 - 乳児用人工心臓用小型遠心ポンプの設計と磁気浮上系の開発
長真啓、増澤徹、巽英介
第49回日本人工臓器学会大会, 2011年11月, 日本人工臓器学会 - 心機能の回復を目的とした磁気浮上型治療用血液ポンプの研究開発
山田悠、増澤徹、大森正芳、前田裕之、西村隆、許俊鋭
第49回日本人工臓器学会大会, 2011年11月, 日本人工臓器学会 - 磁気浮上型全人工心臓の開発
西村宣彦、増澤徹、ティムス ダニエル
第49回日本人工臓器学会大会, 2011年11月, 日本人工臓器学会 - 複合低エネルギを用いた生体組織技術の開発
丸岡寛明、増澤徹、青代敏行、尾関和秀、岸田晶夫、樋上哲哉、加藤綾子
第49回日本人工臓器学会大会, 2011年11月, 日本人工臓器学会 - 完全人工心臓用カスケードポンプ(ACCELPUMP)の左心用ポンプの評価
福長一義、阿部祐輔、山家智之、巽英介、増澤徹、山根隆志、妙中義之、井街宏、舟久保昭夫、福井康裕
第49回日本人工臓器学会大会, 2011年11月, 日本人工臓器学会 - 両心室補助人工心臓への適用を目的としたアキシャル磁気浮上モータの浮上回転特性
栗田伸幸、石川赴夫、手塚孝幸、増澤徹、ダニエル ティムズ
第54回自動制御連合講演会, 2011年11月 - 人工心臓用磁気浮上モータにおけるロータ変位の影響
小沼弘幸、浮田啓悟、増澤徹
第54回自動制御連合講演会, 2011年11月 - 複合低エネルギを用いた鉗子型接合装置の加熱制御
青代敏行、増澤徹、丸岡寛明、尾関和秀、加藤綾子、樋上哲哉、岸田晶夫
第54回自動制御連合講演会, 2011年11月 - A radial type self-bearing motor for small maglev regenerative blood pump
Keigo Ukita; Toru Masuzawa; Hiroyuki Onuma; Takashi Nishimura; Shunei Kyo
The 20th MAGDA COnference in Pacific Asia, 2011年11月, 日本AEM学会 - Development of Lorentz force type tilt control motor for rotary blood pumps
Takannori Ichinose; Toru Masuzawa; Ulrich Steinseifer; Daniel Timms
The 20th MAGDA COnference in Pacific Asia, 2011年11月, 日本AEM学会 - Miniaturized axial gap maglev motor with vector control for pediatric artificial hear
Masahiro Osa; Toru Masuzawa; Eisuke Tatsumi
The 20th MAGDA COnference in Pacific Asia, 2011年11月, 日本AEM学会 - BiVACORⓇ-A Magnetically levited biventricular artificial heart
Daniel Timms; Nobuyuki Kurita; Nicholas Greatrex; Toru Masuzawa
The 20th MAGDA COnference in Pacific Asia, 2011年11月, 日本AEM学会 - 誘導加熱を用いた手術用生体融着システムの検討
秋山直矢、柴建次、岸田昌夫、尾関和秀、増澤徹
生活生命支援医療福祉工学系連合大会2011, 2011年11月, ライフサポート学会 - 新規せん断負荷装置を使用したせん断流れ場における高粘度ウシ血液の溶血特性
丸山修、玉置将也、西田正浩、山根隆志、松田健一、足立吉數、増澤徹
生活生命支援医療福祉工学系連合大会2011, 2011年11月, ライフサポート学会 - 磁気浮上モータを用いた全人工心臓のポンプ性能
西村宣彦、増澤徹、Daniel L Timms
生活生命支援医療福祉工学系連合大会2011, 2011年11月, ライフサポート学会 - 心機能回復のための治療用血液ポンプの研究開発
山田悠、増澤徹、西村隆、許俊鋭
生活生命支援医療福祉工学系連合大会2011, 2011年11月, ライフサポート学会 - 人工心臓の性能評価のための循環系シミュレータの研究開発
須田佳裕、増澤徹、黒崎亘
生活生命支援医療福祉工学系連合大会2011, 2011年11月, ライフサポート学会 - 複合低エネルギによる鉗子型融着デバイスの温度制御技術
丸岡寛明、増澤徹、青代敏行、尾関和秀、加藤綾子、岸田昌夫、樋上哲哉
生活生命支援医療福祉工学系連合大会2011, 2011年11月, ライフサポート学会 - ストロンチウムアパタイト薄膜の作製とその細胞接着性評価
星野智大、尾関和秀、後藤哲哉、増澤徹、青木秀希
生活生命支援医療福祉工学系連合大会2011, 2011年11月, ライフサポート学会 - 微小振動下における細胞接着過程の検討
木村剛、伊藤由樹子、南広祐、加藤綾子、増澤徹、岸田昌夫
生活生命支援医療福祉工学系連合大会2011, 2011年11月, ライフサポート学会 - スパッタリング法を用いたストロンチウムアパタイト薄膜の作製とその細胞応答性
星野智大、尾関和秀、後藤哲哉、増澤徹、青木秀希
第19回茨城講演会, 2011年08月 - 複合低エネルギによる金属と生体組織の接合技術
丸岡寛明、増澤徹、青代敏行、尾関和秀、加藤綾子、岸田昌夫、樋上哲哉
第19回茨城講演会, 2011年08月 - IPM型5軸制御セルフベアリングモータに関する研究
佐藤心平、松田健一、近藤良、増澤徹
第19回茨城講演会, 2011年08月 - 補助人工心臓用アキシャル型磁気軸受の最適化に関する研究
西村宣彦、増澤徹、寺山昌幸、Daniel L Timms
第19回茨城講演会, 2011年08月 - 動圧軸受血液ポンプのための傾き制御機構の研究開発
須田佳裕、増澤徹、一ノ瀬高紀、ダニエル・ティムズ、ウーリッヒ・スタインセイファー
第19回茨城講演会, 2011年08月 - 循環補助用小型磁気浮上摩擦血液ポンプの研究開発
山田悠、増澤徹、浮田啓悟、西村隆、許俊鋭
第19回茨城講演会, 2011年08月 - コーン・シリンダー型レオメーターを使用したせん断流れ場におけるウシ血液の溶血特性、
丸山修、玉置将也、西田正浩、山根隆志、松田健一、足立吉數、増澤徹
第19回茨城講演会, 2011年08月 - 誘導加熱を用いた手術用生体融着システムの検討-周波数変化における温度特性-
秋山直矢、柴建次、岸田昌夫、尾関和秀、増澤徹
第19回茨城講演会, 2011年08月 - 小型ローレンツ型磁気浮上モータのサーボモータ制御
岡田養二、三好理文、増澤徹、榎園正人
第23回「電磁力関連のダイナミクス」シンポジウム, 2011年05月 - 人工心臓のための12突極ラジアル型磁気浮上モータにおける最適極数の検討
小沼弘幸、浮田啓悟、増澤徹
第23回「電磁力関連のダイナミクス」シンポジウム, 2011年05月 - 全人工心臓用磁気浮上モータの磁気支持性能
増澤徹、寺山昌幸、ダニエル L ティムス
第23回「電磁力関連のダイナミクス」シンポジウム, 2011年05月 - 医療用高分子材料の表面特性と接着
中村奈緒子、南広祐、木村剛、増澤徹、岸田昌夫
第50回日本生体医工学会大会, 2011年04月 - 微小振動を用いた小型組織融着装置の開発
笠原康佑、南広祐、木村剛、清水繁、青代敏行、増澤徹、岸田昌夫
第50回日本生体医工学会大会, 2011年04月 - 乳児用人工心臓専用磁気浮上モータのベクトル制御
長真啓、増澤徹、巽英介
第50回日本生体医工学会大会, 2011年04月 - 磁気浮上型治療用血液ポンプの開発
北郷将史、増澤徹、西村隆、許俊鋭
第50回日本生体医工学会大会, 2011年04月 - 人工心臓のための磁気浮上技術
増澤徹
第50回日本生体医工学会大会, 2011年04月 - 磁気浮上型両心補助用人工心臓の研究開発
寺山昌幸、増澤徹、西村宣彦、ダニエル L ティムス
第50回日本生体医工学会大会, 2011年04月 - 小型磁気浮上摩擦血液ポンプの研究開発
浮田啓悟、増澤徹、小沼弘幸、西村隆、許俊鋭
第50回日本生体医工学会大会, 2011年04月 - 動圧血液ポンプのための傾き制御モータの開発
一ノ瀬型の理、増澤徹、ダニエル ティムス、ウーリッヒ スタインセイファー
第50回日本生体医工学会大会, 2011年04月 - 複合低エネルギによる鉗子型組織接合装置の開発
青代敏行、増澤徹、猪野学、尾関和秀、加藤綾子、岸田昌夫、木村剛、樋上哲哉
第50回日本生体医工学会大会, 2011年04月 - 動圧軸受血液ポンプのための傾き制御モータの提案
一ノ瀬高紀、増澤徹、Ulrich Steinseif、Daniel L Timms
第39回人工心臓と補助循環懇話会, 2011年03月 - 循環補助用超小型非接触摩擦ポンプの研究開発
浮田啓悟、増澤徹、小沼弘幸、西村隆、許俊鋭
第39回人工心臓と補助循環懇話会, 2011年03月 - ベクトル制御を用いた乳児用小型磁気浮上人工心臓の開発
長真啓、増澤徹、巽英介
第20回ライフサポート学会フロンティア講演会, 2011年03月 - スパッタリング法を用いたストロンチウムアパタイト薄膜の作製と物性評価
星野智大、尾関和秀、増澤徹、青木秀希
第20回ライフサポート学会フロンティア講演会, 2011年03月 - 循環補助用小型磁気浮上摩擦ポンプの研究開発
山田悠、増澤徹、浮田啓悟、小沼弘幸、西村隆、許俊鋭
第20回ライフサポート学会フロンティア講演会, 2011年03月 - 人工心臓用アキシャル型磁気軸受の最適化に関する研究
西村宣彦、増澤徹、寺山昌幸、Daniel L Timms
第20回ライフサポート学会フロンティア講演会, 2011年03月 - 動圧軸受血液ポンプのための小型傾き制御用磁気軸受の提案
須田佳裕、増澤徹、一ノ瀬隆紀、Ulrich Steinseifer、Daniel L Timms
第20回ライフサポート学会フロンティア講演会, 2011年03月 - 誘導加熱を用いた手術用生体融着システム
秋山直矢、柴建次、尾関和秀、増澤徹
第20回ライフサポート学会フロンティア講演会, 2011年03月 - 微小振動を用いた小型組織融着装置の開発
笠原康佑、南広祐、木村剛、清水繁、青代敏行、増澤徹、岸田昌夫
第20回ライフサポート学会フロンティア講演会, 2011年03月 - 複合低エネルギを用いた金属と生体組織の接合技術
丸岡寛明、増澤徹、青代敏行、尾関和秀、加藤綾子、岸田昌夫、樋上哲哉
第20回ライフサポート学会フロンティア講演会, 2011年03月 - 人工心臓のための磁気浮上モータの設計
浮田啓悟、増澤徹、小沼弘幸、西村隆、許俊鋭
日本生体医工学会関東支部若手研究者発表会2010, 2010年11月 - 低エネルギ複合による鉗子型融着デバイスの開発
猪野学、増澤徹、青代敏行、尾関和秀、岸田晶夫、木村剛、樋上哲也、加藤綾子
日本生体医工学会関東支部若手研究者発表会2010, 2010年11月 - 乳児用人工心臓用ダブルステータ型磁気浮上モータの開発
長真啓、増澤徹、巽英介
第19回MAGDAコンファレンスin 札幌, 2010年11月 - 治療用人工心臓のためのアキシャル型磁気浮上モータの開発
北郷将史、増澤徹、西村隆、許俊鋭
第19回MAGDAコンファレンスin 札幌, 2010年11月 - 両心補助および全人工心臓を目指した磁気浮上人工心臓BiVACOR
増澤徹
第48回日本人工臓器学会大会, 2010年11月 - 複合低エネルギによる金属と生体組織接合技術の開発
青代敏行、増澤徹、猪野学、尾関和秀、加藤綾子、岸田晶夫、木村剛、樋上哲也
第48回日本人工臓器学会大会, 2010年11月 - 両心補助用人工心臓のためのインペラ位置可変磁気浮上モータの開発
寺山昌幸、増澤徹、Dniel L Timms
第48回日本人工臓器学会大会, 2010年11月 - 自己心機能回復を目的とした磁気浮上型人工心臓の開発
北郷将史、増澤徹、浮田啓悟、西村隆、許俊鋭
第48回日本人工臓器学会大会, 2010年11月 - ダブルステータ型磁気浮上モータを用いた乳児用人工心臓の開発
長真啓、増澤徹、巽英介
日本定常流ポンプ研究会2010, 2010年11月 - 磁気浮上人工心臓における浮上インペラの変動要因の検討
小沼弘幸、浮田啓悟、増澤徹
第53回自動制御連合講演会, 2010年11月 - オンチップ細胞機能制御のための圧電駆動型マイクロ細胞培養デバイスの開発 -細胞導入の効率化と細胞実験の基礎的検討-
山田侑平、大竹英明、柴田隆行、川島貴弘、永井萌土、増澤徹、木村剛、岸田晶夫
第53回自動制御連合講演会, 2010年11月 - 弾性ヒンジ機構を用いたナノ振動細胞加振装置の開発
加藤綾子、増澤徹、青代敏行、木村孝之、岸田晶夫、伊藤由樹子、木村剛
生活生命支援医療福祉工学系連合大会2010, 2010年09月 - 微小振動融着法を用いた高分子コラーゲン間の接着
笠原康佑、山本健二、舩本誠一、南広祐、木村剛、清水繁、青代敏行、増澤徹、岸田晶夫
生活生命支援医療福祉工学系連合大会2010, 2010年09月 - 低エネルギ生体融着デバイスの発熱機構の開発
猪野学、増澤徹、青代敏行、尾関和秀、加藤綾子、岸田晶夫、樋上哲哉
生活生命支援医療福祉工学系連合大会2010, 2010年09月 - せん断流れ場における表面粗さに基づく溶血特性-高粘度血液を使用した実験-
丸山修、江尻賢治、西田正浩、山根隆志、永井文秀、足立吉數、増澤徹
生活生命支援医療福祉工学系連合大会2010, 2010年09月 - 乳児用小型磁気浮上人工心臓の開発
長真啓、増澤徹、巽英介
生活生命支援医療福祉工学系連合大会2010, 2010年09月 - 乳児用磁気浮上人工心臓の研究開発
一ノ瀬高紀、長真啓、増澤徹、巽英介
茨城講演会, 2010年08月 - 急性心不全を対象とした磁気浮上人工心臓の研究開発
浮田啓悟、北郷将史、増澤徹、西村隆、許俊鋭
茨城講演会, 2010年08月 - Miniaturized magnetically levitated motor for pediatric artificial heart
Masahiro Osa; Toru Masuzawa; Eisuke Tatsumi
12th International Symposium on Magnetic Bearings, 2010年08月 - 心機能代替プロジェクト「小型な人工心臓が心臓を補助する」
増澤徹
第49回日本生体医工学会大会, 2010年06月 - Magnetically levitated therapeutic artificial heart
北郷将史、増澤徹、浮田啓悟、西村隆、許俊鋭
第49回日本生体医工学会大会, 2010年06月 - Current development status of artificial heart
増澤徹
第49回日本生体医工学会大会, 2010年06月 - Adhesion technology using integrated low level energies
加藤綾子、増澤徹、青代敏行、河野貴宏、岸田晶夫、木村剛、樋上哲哉
第49回日本生体医工学会大会, 2010年06月 - Nano vibration cell stimulus device
加藤綾子、増澤徹、青代敏行、小林亜美子、木村孝之、岸田晶夫、伊藤由樹子
第49回日本生体医工学会大会, 2010年06月 - Development of cell culture microdevice integrated with piezoelectric thin film actuator for on-chip regulation of cell functions
川島貴弘、松澤勇太、山田侑平、柴田隆行、増澤徹、木村剛、岸田晶夫
第49回日本生体医工学会大会, 2010年06月 - IPM型5軸制御セルフベアリングモータの提案
松田健一、Mohd Syawqei、近藤良、増澤徹
第22回「電磁力関連のダイナミクス」シンポジウム, 2010年05月 - 低エネルギ複合による生体組織接合デバイスの開発
青代敏行、増澤徹、河野貴宏、岸田晶夫、樋上哲哉、加藤綾子
第22回「電磁力関連のダイナミクス」シンポジウム, 2010年05月 - シングルモータ方式磁気浮上型両心補助人工心臓の研究開発
寺山昌幸、増澤徹、ダニエル L ティムス
第22回「電磁力関連のダイナミクス」シンポジウム, 2010年05月 - 斜流式磁気浮上人工心臓に関する研究
松井寿定、増澤徹、巽英介
第19回ライフサポート学会フロンティア講演会, 2010年03月 - 急性心不全患者を対象とした治療用人工心臓の研究開発
浮田啓悟、増澤徹、北郷将史、西村隆、許俊鋭
第19回ライフサポート学会フロンティア講演会, 2010年03月 - 乳幼児用磁気浮上人工心臓の研究開発
一ノ瀬高紀、増澤徹、長真啓、巽英介
第19回ライフサポート学会フロンティア講演会, 2010年03月 - オンチップ細胞機能制御のための圧電駆動型マイクロ細胞培養デバイスの開発
松澤勇太、山田侑平、柴田隆行、川島貴弘、増澤徹、木村剛、岸田晶夫
第19回ライフサポート学会フロンティア講演会, 2010年03月 - 乳児対象小型磁気浮上人工心臓の研究開発
長真啓、増澤徹、巽英介
第38回人工心臓と補助循環懇話会, 2010年02月 - 磁気浮上型両心補助用人工心臓の研究開発
寺山昌幸、増澤徹、北郷将史、Daniel L Timms
第38回人工心臓と補助循環懇話会, 2010年02月 - 人工心臓開発の要素技術の現状と展望 磁気浮上技術
増澤徹
第38回人工心臓と補助循環懇話会, 2010年02月, [招待有り] - 小型人工心臓のための全軸制御型磁気浮上斜流ポンプ
増澤徹、松井寿定、巽英介
第22回代用臓器・再生医学研究会, 2010年01月 - Magnetic suspension technology for 3rd generation blood pumps
Toru Masuzawa
KNU & KAOC international symposium, 2009年11月, Kangwon National University Artificial Heart Center, Korea University Korea Artificial Organ Center - 磁束集束ローレンツ型磁気浮上モータの研究
岡田養二、北郷将史、伊佐川晃平、増澤徹、榎園正人
第18回MAGDAコンファレンスin東京, 2009年11月 - 両心補助人工心臓BiVACOR Bi-VAD用磁気浮上モータ
増澤徹、佐々木瑛介、ダニエル L ティムス
第18回MAGDAコンファレンスin東京, 2009年11月 - 一体型アキシャル磁気浮上モータを用いた両心補助/全人工心臓BiVACOR
増澤徹、Daniel Timms
日本定常流ポンプ研究会2009, 2009年11月 - 高耐久性、高生体適合性を実現する磁気浮上技術
増澤徹
第47回日本人工臓器学会大会, 2009年11月, [招待有り] - 斜流式人工心臓の磁気浮上インペラに作用する流体力の検討
松井寿定、増澤徹、巽英介
第47回日本人工臓器学会大会, 2009年11月 - 小型両心補助用磁気浮上人工心臓の研究開発
北郷将史、増澤徹、松井寿定、寺山昌幸、ティムズ ダニエル
第47回日本人工臓器学会大会, 2009年11月 - 新生児・乳児用小型人工心臓のための磁気浮上系の開発
長真啓、増澤徹、巽英介
第47回日本人工臓器学会大会, 2009年11月 - 両心補助用人工心臓のための一体型アキシャル磁気浮上モータの開発
北郷将史、増澤徹、佐々木瑛祐、Daniel Timms
第7回生活支援工学系学会連合大会, 2009年09月 - 食品容器を目的とした光触媒/DLC膜の消臭性評価
尾関和秀、大石信洋、宮沢真吾、平栗健二、増澤徹
第7回生活支援工学系学会連合大会, 2009年09月 - 弾性ヒンジを用いたナノ振動細胞加振装置の開発
小林亜美子、増澤徹、加藤綾子、木村孝之、木村剛、岸田晶夫
第7回生活支援工学系学会連合大会, 2009年09月 - 微小振動融着法による高分子材料-生体組織間の接着に関する研究
山本健二、木村剛、南広祐、加藤綾子、清水繁、樋上哲哉、増澤徹、岸田晶夫
第7回生活支援工学系学会連合大会, 2009年09月 - せん断流れ場において表面粗さに基づく溶血特性-せん断応力の増加と溶血量増加の相関
丸山修、阿部純也、西田正浩、山根隆志、大島郁也、永井文秀、足立吉數、増澤徹
第7回生活支援工学系学会連合大会, 2009年09月 - オンチップ細胞機能制御のための圧電駆動型マイクロ細胞培養デバイスの開発
松澤勇太、柴田隆行、川島貴弘、増澤徹、木村剛、岸田晶夫
第7回生活支援工学系学会連合大会, 2009年09月 - 高性能で小型化が可能な5軸制御セルフベアリングモータの開発
松田健一、石川達也、近藤良、増澤徹
日本機械学会Dynamics and Design Conference 2009, 2009年09月 - 磁束集束ローレンツ浮上モータの提案
岡田養二、北郷将史、増澤徹、榎園正人
日本機械学会Dynamics and Design Conference 2009, 2009年09月 - CVD法により作成されたDLC膜の有機分子の吸着特性評価
宮澤真吾、尾関和秀、平栗健二、増澤徹
茨城講演会, 2009年08月 - 歯科インプラント実習を目的としたアパタイト/レジン模擬骨に関する研究
稲垣尭久、尾関和秀、増澤徹、青木秀希、宇佐美諒真
茨城講演会, 2009年08月 - 新生児・乳幼児用人工心臓のための磁気浮上モータの開発
長真啓、増澤徹、巽英介
茨城講演会, 2009年08月 - 人工心臓適用を目指した5軸制御セルフベアリングモータの小型化に関する研究
寺山昌幸、松田健一、増澤徹、近藤良
茨城講演会, 2009年08月 - 粗さを付加したときの表面付近のせん断応力場に関する数値解析
西田正浩、丸山修、山根隆志、増澤徹、永井文秀
茨城講演会, 2009年08月 - 血液のせん断流れ場において金属材料表面粗さが溶血に及ぼす影響
丸山修、西田正浩、山根隆志、永井文秀、足立吉數、増澤徹
茨城講演会, 2009年08月 - 4軸制御型磁気軸受を用いた磁気浮上クリーンポンプの研究開発
黒須寛秋、増澤徹、加藤綾子、小沼弘幸、柿原功一
日本AEM学会, 2009年06月 - 両心室補助人工心臓への応用を目的としたアキシャル磁気浮上モータの開発
栗田伸幸、Daniel Timms、Nicholas Greatrex、増澤徹
第21回「電磁力関連のダイナミクス」シンポジウム, 2009年05月 - 5軸制御セルフベアリングモータの小型化に関する研究
松田健一、寺山昌幸、増澤徹、近藤良
第21回「電磁力関連のダイナミクス」シンポジウム, 2009年05月 - 複合低エネルギ組織融着技術の研究開発
河野貴宏、増澤徹、加藤綾子、尾関和秀、岸田晶夫、木村剛、樋上哲哉
第21回「電磁力関連のダイナミクス」シンポジウム, 2009年05月 - 斜流式人工心臓のための磁気浮上モータシステムの開発
松井寿定、増澤徹、巽英介
第21回「電磁力関連のダイナミクス」シンポジウム, 2009年05月 - 医用アクチュエータの最新の話題、電磁駆動アクチュエータ(回転):磁気浮上モータ
増澤徹
第48回日本生体医工学会大会, 2009年04月, [招待有り] - 顕微鏡に設置可能なナノ振動細胞刺激装置の開発
小林亜美子、増澤徹、加藤綾子、木村孝之、岸田晶夫
第48回日本生体医工学会大会, 2009年04月 - 微笑振動付加による種々の細胞の基材への接着と増殖の効果
吾郷友亮、伊藤由樹子、木村剛、南広祐、加藤綾子、増澤徹、岸田晶夫
第48回日本生体医工学会大会, 2009年04月 - ナノ振動融着法による高分子材料‐生体組織間の接着に関する研究
山本健二、宮廻寛、木村剛、南広祐、加藤綾子、栗田公夫、樋上哲哉、増澤徹、岸田晶夫
第48回日本生体医工学会大会, 2009年04月 - 複合低エネルギ-を利用した組織融着に関する研究
河野貴宏、増澤徹、加藤綾子、尾関和秀、岸田晶夫、木村剛、樋上哲哉
第48回日本生体医工学会大会, 2009年04月 - 斜流式人工心臓用磁気軸受の開発
松井寿定、増澤徹、巽英介
第48回日本生体医工学会大会, 2009年04月 - フッ素添加DLC膜のタンパク質吸着特性評価
尾関和秀、平栗健二、増澤徹
第48回日本生体医工学会大会, 2009年04月 - 身体活動度モニタリングスーツによる日常生活活動のエネルギー消費量推定
加藤綾子、増澤徹、石井博徳、植野彰規
第48回日本生体医工学会大会, 2009年04月 - 培養細胞を対象としたナノ振動加振装置の振動特性解析
小林亜美子、増澤徹、加藤綾子、木村孝之、岸田晶夫
日本機械学会関東支部第15期総会講演会, 2009年03月 - 複合低エネルギを利用した組織融着技術に関する研究
河野貴宏、増澤徹、加藤綾子、尾関和秀、岸田晶夫、木村剛、樋上哲哉
日本機械学会関東支部第15期総会講演会, 2009年03月 - DT-QOL向上のための技術開発とは?デバイス故障と闘う軸受技術
増澤徹
第37回人工心臓と補助循環懇話会, 2009年02月, [招待有り] - 多軸制御型斜流式磁気浮上人工心臓の研究開発
松井寿定、増澤徹、巽英介
第37回人工心臓と補助循環懇話会, 2009年02月 - 茨城大学における磁気浮上型人工心臓の研究開発
増澤徹
つくば医工連携フォーラム2009, 2009年01月 - 両心補助用人工心臓BIVACOR Bi-VADの開発
増澤徹、佐々木瑛祐、栗田伸幸、ダニエル ティムス
日本定常流ポンプ研究会, 2008年11月 - 人工内臓から内蔵機器へ-人工臓器“体内埋込技術”の新展開
増澤徹
第46回日本人工臓器学会大会, 2008年11月 - 人工心臓の仕組み
増澤徹
第46回日本人工臓器学会大会, 2008年11月 - 非定常CFD解析による磁気浮上型遠心ポンプのインペラに働く流体力の推定
増澤徹、松井寿定、田中伸厚、築谷朋典、銭逸
第46回日本人工臓器学会大会, 2008年11月 - 種々の細胞機能に対する機械的ナノ振動刺激の影響に関する検討
伊藤由樹子、吾郷友亮、木村剛、南広祐、小林亜美子、加藤綾子、増澤徹、岸田晶夫
第46回日本人工臓器学会大会, 2008年11月 - 斜流式磁気浮上型人工心臓の開発
松井寿定、増澤徹、巽英介
第46回日本人工臓器学会大会, 2008年11月 - 表面粗さを付加した回転せん断負荷装置内の流れと溶血との関係
西田正浩、丸山修、山根隆志、永井文秀、大島郁也、増澤徹
第46回日本人工臓器学会大会, 2008年11月 - 4軸制御型磁気軸受を用いた磁気浮上クリーンポンプの研究開発
黒須寛秋、増澤徹、加藤綾子、小沼弘幸、柿原功一
第17回MAGDAコンファレンスin 日立, 2008年11月 - 5軸制御型セルフベアリングモータの傾き制御特性
石川達也、松田健一、増澤徹、近藤良
第17回MAGDAコンファレンスin 日立, 2008年11月 - 両心補助人工心臓BIVACOR Bi-VADの磁気浮上システムの開発
佐々木瑛祐、増澤徹、栗田伸幸
リニアドライブ研究会, 2008年11月 - 複合低エネルギ利用による低損傷生体組織融着技術における伝熱特性の影響
加藤綾子、増澤徹、河野貴宏、木村孝之、尾関和秀、岸田晶夫、木村剛、樋上哲哉、佐藤裕一郎、山本芳郎
第6回生活支援工学系学会連合大会, 2008年09月 - せん断流れ場において表面粗さの大きさとせん断応力が溶血に及ぼす影響
丸山修、川口雄大、米谷幸治、西田正浩、山根隆志、永井文秀、足立吉數、増澤徹
第6回生活支援工学系学会連合大会, 2008年09月 - 表面粗さを付加した回転せん断負荷装置内の流れ解析
西田正浩、塚越洋之、川口雄大、丸山修、山根隆志、増澤徹、永井文秀
第6回生活支援工学系学会連合大会, 2008年09月 - 新しい低損傷生体組織融着技術によるステントグラフト融着の評価
加藤綾子、増澤徹、河野貴宏、木村孝之、尾関和秀、岸田晶夫、木村剛、樋上哲哉、佐藤裕一郎、山本芳郎
第6回生活支援工学系学会連合大会, 2008年09月 - 両心補助用人工心臓BIVACOR Bi-VADのための磁気浮上系の開発
増澤徹、佐々木瑛祐、栗田伸幸、ダニエル ティムズ
第6回生活支援工学系学会連合大会, 2008年09月 - スパッタHA薄膜の薬剤吸着特性と抗血栓性評価
尾関和秀、吉原裕貴、増澤徹
第6回生活支援工学系学会連合大会, 2008年09月 - 身体活動度モニタリングスーツによるエネルギー消費量の推定
石井博徳、増澤徹、加藤綾子
第6回生活支援工学系学会連合大会, 2008年09月 - Ti・ステンレス基材に対するSi中間層を用いたDLC膜の密着性の研究
佐藤実、永島勲、尾関和秀、増澤徹
茨城講演会, 2008年09月 - 斜流式磁気浮上人工心臓用ポンプの研究開発
松井寿定、増澤徹、巽英介
茨城講演会, 2008年09月 - 表面粗さを付加した回転せん断付加装置内の数値解析
西田正浩、柳生祥丈、丸山修、山根隆志、増澤徹、永井文秀、大島郁也
茨城講演会, 2008年09月 - カテーテル型ステント融着マニピュレータに関する開発
河野貴宏、増澤徹、加藤綾子、尾関和秀、岸田晶夫、木村剛、樋上哲哉、佐藤裕一郎、山本芳郎
茨城講演会, 2008年09月 - ナノ振動細胞刺激装置の振動特性解析
小林亜美子、増澤徹、加藤綾子、木村孝之、岸田晶夫、木村剛
茨城講演会, 2008年09月 - 5-DOF controlled self-bearing motor
Tatsuya Ishikawa; Ken-ichi Matsuda; Toru Masuzawa; Ryou Kondo
11th International Symposium on Magnetic Bearings, 2008年08月 - Wide gap magnetic bearing system for a magnetically suspended clean pump
Hiroaki Kurosu; Toru Masuzawa; Ayako Katoh; Kenichi Suzuki
11th International Symposium on Magnetic Bearings, 2008年08月 - Evaluation of a new hybrid magnetic bearing for the bivacor BI-VAD/TAH
Eisuke Sasaki; Toru Masuzawa; Nobuyuki Kurita; Daniel Timms
ASAIO 54th Annual conference, 2008年06月 - 扁平型ハイブリッド磁気軸受の最適化設計
加藤綾子、増澤徹、鈴木健一
第20回「電磁力関連のダイナミクス」シンポジウム, 2008年05月 - 複合低エネルギを用いた生体組織と人工物の融着技術の開発
加藤綾子、増澤徹、尾関秀和、木村孝之、岸田晶夫、木村剛、樋上哲哉、佐藤裕一郎; 山本芳郎
第47回日本生体医工学会大会, 2008年05月 - 身体活動度モニタスーツの開発
石井博徳、増澤徹、加藤綾子
第47回日本生体医工学会大会, 2008年05月 - カテーテル型ステント融着マニピュレータに関する開発研究
河野貴宏、増澤徹、加藤綾子、濱口崇志、尾関和秀、木村孝之、岸田晶夫、木村剛、樋上哲哉、佐藤裕一郎、山本芳郎
人と福祉を支える技術フォーラム2008, 2008年03月, ライフサポート学会 - 斜流式人工心臓用ポンプの研究開発
松井寿定、増澤徹、太田晶子、巽英介
人と福祉を支える技術フォーラム2008, 2008年03月, ライフサポート学会 - 磁気浮上人工心臓ポンプの非定常CFD解析
太田晶子、増澤徹、田中伸厚、銭逸、築谷朋典
人と福祉を支える技術フォーラム2008, 2008年03月, ライフサポート学会 - 「細胞を対象とした工学研究」の共通概念の構築―機械工学サイドから―
増澤徹
人と福祉を支える技術フォーラム2008, 2008年03月, ライフサポート学会 - ナノ振動細胞刺激装置の開発研究
小林亜美子、増澤徹、加藤綾子、木村孝之、橋本健児、岸田晶夫、木村剛
人と福祉を支える技術フォーラム2008, 2008年03月, ライフサポート学会 - 両心補助用人工心臓のためのハイブリッド型磁気軸受の開発
佐々木瑛祐、増澤徹
第36回人工心臓と補助循環懇話会, 2008年03月, 東京電機大学理工学部電子情報工学科 福井康裕(世話人) - 小型磁気浮上斜流ポンプの研究開発
黒須寛秋、鈴木健一、加藤綾子、増澤徹
第36回人工心臓と補助循環懇話会, 2008年03月, 東京電機大学理工学部電子情報工学科 福井康裕(世話人) - 5軸能動制御型セルフベアリングモータの開発
松田健一、石川達也、増澤徹、近藤良
第16回MAGDAコンファレンスin京都, 2007年11月, 日本AEM学会 - 磁気軸受用センサの開発
岡田養二、石川達也、増澤徹、近藤良
第16回MAGDAコンファレンスin京都, 2007年11月, 日本AEM学会 - 扁平型ハイブリッド磁気軸受の開発
鈴木健一、増澤徹
第16回MAGDAコンファレンスin京都, 2007年11月, 日本AEM学会 - ハイブリッド型磁気軸受を用いた磁気浮上型血液ポンプの開発
鈴木健一、増澤徹
第5回生活支援工学系学会連合大会, 2007年10月, ライフサポート学会 - 循環系治療機器の工学的評価に関する研究
石塚健太郎、増澤徹、加藤綾子、岸田晶夫、ダニエルLティムス
第5回生活支援工学系学会連合大会, 2007年10月, ライフサポート学会 - 磁気浮上人工心臓ポンプの非定常CFD解析
太田晶子、増澤徹、田中伸厚、銭逸、築谷朋典
第5回生活支援工学系学会連合大会, 2007年10月, ライフサポート学会 - ナノ振動刺激時における細胞膜近傍の剪断応力解析
橋本健児、増澤徹、木村孝之、加藤綾子、岸田晶夫、木村剛
第5回生活支援工学系学会連合大会, 2007年10月, ライフサポート学会 - 低エネルギ複合による生体接合技術の開発
濱口崇志、増澤徹、加藤綾子、尾関和秀、木村孝之、岸田晶夫、木村剛、樋上哲哉、佐藤裕一郎、山本芳郎
第5回生活支援工学系学会連合大会, 2007年10月, ライフサポート学会 - 層流せん断流れ場において材料表面粗さが溶血に及ぼす影響
川口雄大、丸山修、西田正弘、山根隆志、永井文秀、足立吉數、増澤徹
第5回生活支援工学系学会連合大会, 2007年10月, ライフサポート学会 - 人工心臓のための小型ハイブリッド型磁気軸受
増澤徹、鈴木健一、黒須寛秋、加藤綾子
電気学会研究会, 2007年10月, 電気学会 - 健康管理ロボットによる食事摂取量計測に関する基礎的研究
石井博徳、増澤徹、加藤綾子
茨城講演会, 2007年09月, 日本機械学会 - 循環系シミュレータの開発と磁気浮上型人工心臓の評価
黒須寛秋、増澤徹、石塚健太郎、Daniel L Timms
茨城講演会, 2007年09月, 日本機械学会 - ダブルバイアス磁束型磁気浮上血液ポンプの開発
佐々木瑛祐、増澤徹、小沼弘幸
茨城講演会, 2007年09月, 日本機械学会 - SPH法と格子法の組み合わせによるメゾスケール血流解析
中村信之、田中伸厚、増澤徹
茨城講演会, 2007年09月, 日本機械学会 - 人工心臓内の材料表面粗さによるせん断応力と血球破壊に関する研究
川口雄大、丸山修、西田正弘、山根隆志、永井文秀、足立吉數、増澤徹
茨城講演会, 2007年09月, 日本機械学会 - 人工心臓の最近の進歩
増澤徹
体外循環と補助循環2007 第23回日本人工臓器学会教育セミナー, 2007年07月, 日本人工臓器学会 - 人工心臓用ダブルバイアス磁束型磁気浮上システム
増澤徹、加藤裕介、佐々木瑛祐、小沼弘幸
第19回電磁力関連のダイナミクスシンポジウム, 2007年05月, 日本機械学会 - ナノ振動負荷時の細胞周りの剪断応力解析
橋本健児、増澤徹、木村孝之、加藤綾子、岸田晶夫、木村剛
第46回日本生体医工学会大会, 2007年04月, 日本生体医工学会 - 人工心臓ポンプ内の流れが磁気浮上インペラに及ぼす影響
太田晶子、増澤徹、銭逸
第46回日本生体医工学会大会, 2007年04月, 日本生体医工学会 - 複数低エネルギーの複合化による新しい生体接合技術の開発
濱口崇志、増澤徹、加藤綾子、尾関和秀、木村孝之、岸田晶夫、木村剛、樋上哲哉、佐藤裕一郎、山本芳郎
第46回日本生体医工学会大会, 2007年04月, 日本生体医工学会 - 磁気浮上型人工心臓評価のための循環系シミュレータの開発
黒須寛秋、増澤徹、石塚健太郎
人と福祉を支える技術フォーラム2007, 2007年03月, ライフサポート学会 - 磁気浮上血液ポンプの高機能化に関する研究
佐々木瑛祐、増澤徹、加藤裕介
人と福祉を支える技術フォーラム2007, 2007年03月, ライフサポート学会 - 斜流ポンプ人工心臓のための小型磁気軸受の開発
中山直久、増澤徹、鈴木健一、加藤綾子
人と福祉を支える技術フォーラム2007, 2007年03月, ライフサポート学会 - 健康管理パーソナルロボットに関する基礎的研究
石井博徳、増澤徹、加藤綾子
人と福祉を支える技術フォーラム2007, 2007年03月, ライフサポート学会 - 定常流ポンプ用磁気浮上技術
増澤徹
日本定常流ポンプ研究会・第12回日本臨床補助人工心臓研究会, 2006年10月 - 定常流ポンプ用磁気浮上技術
増澤徹
日本定常流ポンプ研究会・第12回日本臨床補助人工心臓研究会, 2006年10月 - 中堅研究者からパイオニアへ:研究者として進化するには?
増澤徹
第44回日本人工臓器学会大会, 2006年10月, [招待有り] - 2次元的な磁束経路を形成するハイブリッド型磁気軸受の開発
鈴木健一、増澤徹
リニアドライブ研究会, 2006年10月 - 重複バイアス磁束ハイブリッド型磁気軸受の開発
小沼弘幸、村上倫子、柿原功一、増澤徹
リニアドライブ研究会, 2006年10月 - バイアス磁束誘導型磁気軸受を用いた人工心臓の開発
加藤裕介、増澤徹
リニアドライブ研究会, 2006年10月 - 磁気浮上型人工心臓のポンプ流量推定に関する研究
石塚健太郎、増澤徹
第44回日本人工臓器学会大会, 2006年10月 - 人工心臓のためのバイアス磁石対向式ハイブリッド型磁気軸受の開発
鈴木健一、増澤徹
第44回日本人工臓器学会大会, 2006年10月, [招待有り] - 人工心臓用磁気軸受の最適設計法の開発
中山直久、鈴木健一、増澤徹
第44回日本人工臓器学会大会, 2006年10月 - バイアス磁束誘導型磁気軸受を応用した体外循環用血液ポンプの開発
加藤裕介、増澤徹
第44回日本人工臓器学会大会, 2006年10月 - 振動エネルギー利用による生体接合技術の開発
濵口崇志、加藤綾子、尾関和秀、岸田晶夫、木村剛、樋上哲哉、増澤徹
第44回日本人工臓器学会大会, 2006年10月 - 人工心臓の血液接触面の表面粗さが溶血に及ぼす影響
丸山修、米谷幸治、西田正浩、山根隆志、足立吉數、大島郁也、増澤徹
茨城講演会, 2006年09月 - SPH法を用いた血流解析における赤血球モデルの改良
中村信之、田中伸厚、増澤徹
茨城講演会, 2006年09月 - バイアス磁束誘導型磁気浮上人工心臓の開発
加藤裕介、増澤徹
茨城講演会, 2006年09月 - 人工心臓用磁気軸受の最適設計
中山直久、増澤徹、加藤綾子、鈴木健一
茨城講演会, 2006年09月 - 人工心臓用バイパス磁石対向式ハイブリッド型磁気軸受
鈴木健一、増澤徹、青砥良平
茨城講演会, 2006年09月 - ナノ振動が細胞に与える影響
橋本健児、草間淳、加藤綾子、岸田晶夫、木村剛、木村孝之、増澤徹
第4回生活支援工学系学会連合大会, 2006年09月 - 機械的微小振動刺激の細胞分化に及ぼす影響に関する検討
伊藤由樹子、木村剛、南広祐、加藤綾子、増澤徹、岸田晶夫
第4回生活支援工学系学会連合大会, 2006年09月 - 振動エネルギー利用による生体接合技術の開発
濵口崇志、加藤綾子、岸田晶夫、木村剛、樋上哲哉、増澤徹
第4回生活支援工学系学会連合大会, 2006年09月 - 磁気浮上型人工心臓のポンプ流量推定に関する研究
石塚健太郎、増澤徹
第4回生活支援工学系学会連合大会, 2006年09月 - 回転せん断負荷装置内の流れ解析
西田正浩、丸山修、山根隆志、増澤徹、大島郁也
第4回生活支援工学系学会連合大会, 2006年09月 - せん断流れ場において表面粗さの大きさと面積が溶血に及ぼす影響
丸山修、沼田雄亮、米谷幸治、西田正浩、山根隆志、足立吉數、大島郁也、増澤徹
第4回生活支援工学系学会連合大会, 2006年09月 - 人工心臓用小型ハイブリッド磁気軸受の開発
増澤徹、齋藤喬
第18回電磁力関連のダイナミクスシンポジウム, 2006年05月 - 磁気浮上型人工心臓の駆動状態推定方法の開発
増澤徹
第45回日本生体医工学会大会, 2006年05月 - ナノ振動と細胞機能制御
増澤徹、加藤綾子、草間淳、木村孝之、岸田晶夫、木村剛、柴田隆行
第45回日本生体医工学会大会, 2006年05月 - 超音波メス制御による手術支援
加藤綾子、増澤徹、樋上哲哉、岸田晶夫、佐藤裕一郎
第45回日本生体医工学会大会, 2006年05月 - Characteritics of a Two-dimensional Integrated Magnetic Sensor for Position Sensing and Motor Control,
T Kimura; K Takasaki; T Masuzawa
IEEJ Trans, 2006年01月 - 磁気浮上型人工心臓のポンプ流量推定に関する研究
石塚健太郎、増澤徹
第44回日本人工臓器学会大会予稿集, 2006年01月 - Quick touch術式効果の工学的評価と超音波メス制御方式の検討
能田高行、増澤徹、樋上哲哉、岸田晶夫、佐藤裕一郎
第3回生活支援工学系 学会連合大会講演予稿集, 2005年12月 - ナノ微小振動と細胞
増澤徹、草間淳、木村孝之、柴田隆行、岸田晶夫、木村剛
第3回生活支援工学系学会連合大会講演予稿集, 2005年12月 - SPH法による血流シミュレーションの赤血球モデルの比較
早川裕次郎、田中伸厚、増澤徹
第3回生活支援工学系学会 連合大会講演予稿集, 2005年12月 - せん断流れ場において表面粗さが溶血に及ぼす影響
丸山修、西田正浩、山根隆志、大島郁也、足立吉數、増澤徹
第3回生活支援工学系学会連合大会講演予稿集, 2005年12月 - 磁気浮上型人工心臓の技術課題
増澤徹
日本定常流ポンプ研究会, 2005年11月 - 磁気浮上モーターの特性評価を目的とした二次元磁気センサの計測
高崎慶吾、木村孝之、増澤徹
電気学会研究会資料, 2005年11月 - 細胞機能制御のためのMEMS細胞加振デバイスの開発
吉田典央、柴田隆行、堀内宰、増澤徹、岸田晶夫
電気学会研究会資料, 2005年11月 - 人工心臓応用を目指した新しいハイブリッド型磁気軸受の開発
齋藤喬、中山直久、増澤徹
電気学会研究会資料, 2005年11月 - 人工心臓用磁気浮上モータの小型化と高効率化
増澤徹、加藤裕介
電気学会研究会資料, 2005年11月 - 人工心臓に用いる磁性流体封入型動圧軸受に関する研究
小林秀法、増澤徹、大島郁也
茨城講演会 講演論文集, 2005年09月 - 磁気浮上型小型ターボポンプの開発
中山直久、齋藤喬、西田正浩、山根隆志、増澤徹
茨城講演会 講演論文集, 2005年09月 - 人工心臓用アキシャル型磁気浮上遠心ポンプの小型化
加藤裕介、増澤徹
茨城講演会 講演論文集, 2005年09月 - Magnetically suspended pumps for artificial heart
Toru Masuzawa
8th Japanese-Polish Seminar on New Engineering Methods Supporting Human Life, 55,, 2005年09月 - Magulev pump and zero power control
ToruMasuzawa; Hiroyuki Onuma
13th Congress of the ISRBP, 2005年09月 - Hemolysis resulting from surface roughness under shear flow
Osamu Maruyama; Masahiro Nishida; Takashi Yamane; Ikuya Oshima; Yoshikazu Adachi; Toru Masuzawa
13th Congress of the ISRBP, OS-2-3, 62, 2005年09月 - Accuracy enhancement of flow visualization analysis for hemocompatibility evaluation of rotary blood pumps
M Nishida; T Yamane; H Kogure; T Chida; T Masuzawa
13th Congress of the ISRBP, PA-4,116, 2005年09月 - Magunetically suspended pumps for artificial heart
Toru Masuzawa
第8回日本ポーランドセミナー, 2005年09月 - 磁気浮上ポンプによるポンプ室内流体力の推定
増澤徹
第3回生活支援工学系学会連合大会 講演予稿集, 2005年08月 - Cell function control by nano vibrations
J Kusama; T Kimura; T Shibata; A Kishida,T
The First International Student Conference at Ibaraki University, 2005年07月 - Development of a novel hybrid type magnetic bearing and application to micro centrifugal pumps for artificial hearts,
Saito T; Nakayama N; Kakihara K; Okamoto T; Masuzawa T
The First International Student Conference at Ibaraki University, 2005年07月 - Development of two-Dimensional magnetic sensors for characterization of magnetic levitated motors
K Takasaki; T Kimura; T Masuzawa
The First International Student Conference, 2005年07月 - 人工心臓のための磁気浮上軸流ポンプの開発
齋藤喬、山根隆志、西田正浩、増澤徹
第43巻特別号 第44回日本生体医工学会大会プログラム・論文集, 2005年04月 - 人工心臓のためのアキシャル型3軸制御磁気浮上モータの改良
加藤裕介、村上倫子、小沼弘幸、増澤徹
第44回日本生体医工学会大会プログラム・論文集, 2005年04月 - 人工心臓用3軸制御型磁気浮上遠心ポンプの開発
加藤裕介、村上倫子、小沼弘幸、増澤徹
日本機械学会関東支部第11期総会 講演会講演論文集, 2005年03月 - 磁気動圧浮上回転式ポンプ
山根隆志、西田正浩、丸山修、小西義昭、山城直人、増澤徹、岡田養二
日本機械学会関東支部第11期総会講演会 講演論文集, 2005年03月 - 人工心臓のための5軸制御型磁気浮上軸流ポンプの開発
中山直久、齊藤喬、西田正浩、山根隆志、増澤徹
日本機械学会関東支部第11期 総会講演会講演論文集, 2005年03月 - 径方向支持型磁気浮上遠心血液ポンプの開発現況
小沼弘幸、岡田養二、築谷朋典、巽英介、妙中義之、増澤徹
第33回人工心臓と補助循環懇話会 プログラム・抄録集, 2005年01月 - 5軸制御型磁気浮上軸流ポンプの開発
齊藤喬、山根隆志、西田正浩、増澤徹
第33回人工心臓と補助循環懇話会プログラム・抄録集, 2005年01月 - ナノバイブレーションによる細胞機能制御
草間淳、石丸正臣、木村孝之、柴田隆行、岸田晶夫、増澤徹
第33回人工心臓と補助循環懇話会プログラム・抄録集, 2005年01月 - アキシャル型磁気浮上モータを用いた人工心臓用遠心ポンプの開発
小沼弘幸、増澤徹、加藤勇
日本機械学会論文集, 2005年01月 - 人工心臓用ラジアル型磁気浮上遠心ポンプの最適化
小沼弘幸、岡田養二、増澤徹
第17回バイオエンジニアリング講演会講演論文集, 2005年01月 - 血流のミクロ・シミュレーション
高野龍雄、田中伸厚、増澤徹 、
日本機械学会論文集, 2004年11月 - 医療機器の今後10年間の展望、人工臓器-人工心臓を中心に-、
増澤徹
医科器械学 創立80周年記念誌, 2004年06月 - Feed Forward医療の提唱-新しいエムイ-技術創出-
増澤徹
生体医工学 第42巻特別号 第43回日本エム・イー学会大会プログラム・論文集, 2004年05月 - 径方向支持型磁気浮上モータを用いた完全磁気浮上遠心血液ポンプの改良、
小沼弘幸、増澤徹、岡田養二、築谷朋典、妙中義之
生体医工学 第42巻特別号第43回日本エム・イー学会大会プログラム・論文集, 2004年05月 - アキシャル型3軸制御磁気浮上遠心血液ポンプの開発
村上倫子、増澤徹、小沼弘幸
生体医工学第42巻特別号 第43回日本エム・イー学会大会プログラム・論文集, 2004年05月 - インピーダンスを利用した穿刺深さ計測法の開発、
増澤徹、小林誉之、孫彦斌、柴田隆行、岸田晶夫
生体医工学第42巻特別号 第43回日本エム・イー学会大会プログラム・論文集, 2004年05月 - ナノバイブレーションによる細胞機能制御システムの開発
石丸正臣、増澤徹、草間淳、柴田隆行、岸田晶夫、木村剛、宮崎幸造
ナノバイブレーションによる細胞機能制御システムの開発、, 2004年05月 - 実用化にむけた磁気浮上型人工心臓の開発
小沼弘幸; 増澤徹; 大島郁也; 近藤良; 岡田養二
第2回SVBL成果報告会, 2004年03月 - 磁気浮上型人工心臓
増澤徹
電気学会技術報告第958号, 2004年03月 - 軸流ポンプ用小型磁気浮上システムの開発
齋藤喬; 小沼弘幸; 岡田養二; 増澤徹
SVBL第2回成果報告会, 2004年02月 - 生体組織の粘弾性評価に関する研究‐幼児と成人の筋肉の粘弾性評価-
中村太一; 小川真由美; 増澤徹
人と福祉を支える技術フォーラム, 2004年02月 - アキシャル型磁気浮上人工心臓の高機能化に関する研究
大沢卓也; 村上倫子; 小沼弘幸; 増澤徹
人と福祉を支える技術フォーラム, 2004年02月 - ラジアル型磁気浮上人工心臓の改良に関する研究
野津英孝; 小沼弘幸; 増澤徹; 岡田養二; 築谷朋典; 妙中義之
人と福祉を支える技術フォーラム, 2004年02月 - ナノバイブレーションによる細胞機能制御システムの開発
草間淳; 石丸正臣; 増澤徹; 木村孝之; 岸田晶夫; 木村剛; 宮崎幸造
人と福祉を支える技術フォーラム, 2004年02月 - アキシャル型磁気浮上モータを用いた人工心臓の開発
小沼弘幸; 増澤徹
第16回バイオエンジニアリング講演会講演論文集, 2004年01月, [招待有り] - 次世代型磁気浮上定常流ポンプの開発現況
増澤徹,岡田養二
第10回日本定上流ポンプ研究会, 2003年10月 - アキシャル方向支持型磁気浮上モータを使用した遠心血液ポンプの開発
小沼弘幸; 加藤勇; 増澤徹
第41回日本人工臓器学会大会予稿集, 2003年10月 - 5軸制御磁気遠心血液ポンプの開発
村上倫子; 小沼弘幸; 増澤徹; 岡田養二
第41回日本人工臓器学会大会予稿集, 2003年09月 - 人工心臓における材料表面粗さと血球破壊に関する研究
沼田雄亮; 大島郁也; 中村俊一; 増澤徹; 丸山修; 山根隆志; 西田正浩
茨城講演会講演論文集, 2003年09月 - アキシャル型磁気浮上モータを用いた人工心臓用遠心ポンプの開発
小沼弘幸; 増澤徹; 村上倫子; 岡田養二
茨城講演会講演論文集, 2003年09月 - 微小振動による細胞機能刺激に関する研究
石丸正臣; 増澤徹; 柴田隆行; 岸田晶夫; 宮崎幸造
茨城講演会講演論文集, 2003年09月 - 液晶アクティブマスクを用いたDNAチップ合成システムの開発
能田高行,柴田隆行,林照剛,増澤徹,牧野英司,
茨城講演会講演論文集, 2003年09月 - 軸流ポンプ用磁気浮上システムの開発
児嶋次郎; 増澤徹; 小沼弘幸; 岡田養二,山根隆志
生活支援工学系学会連合大会講演予稿集, 2003年05月 - アキシャル型磁気浮上人工心臓の改良
村上倫子,増澤徹,加藤勇,小沼弘幸,岡田養二
生活支援工学系学会連合大会講演予稿集, 2003年05月 - 改良型マイクロカプセル模擬血液を使用した遠心血液ポンプの溶血特性
丸山修,山根隆志,山口勝弘,西田正浩,小野口富夫,軸屋智昭,筒井達夫,増澤徹
生活支援工学系学会連合大会講演予稿集, 2003年05月 - 遠心血液ポンプの設計指標の確立-血液せん断負荷装置内のDNS解析-
小沼弘幸,増澤徹,田中伸厚,中村省一郎,山根隆志
生活支援工学系学会連合大会講演予稿集, 2003年05月 - SPH法を用いた血流のミクロ・モデル解析
高野龍雄,岩田賢,田中伸厚,増澤徹
生活支援工学系学会連合大会講演予稿集, 2003年05月 - 差分法と個別要素法を用いた血流の数値
岩田賢,高野龍雄,田中伸厚,増澤徹
生活支援工学系学会連合大会講演予稿集, 2003年05月 - セルカルチャーのための圧電駆動型バイオマイクロデバイスの開発
棚村大作,柴田隆行,草刈紀行,増澤徹,岸田晶夫
生活支援工学系学会連合大会講演予稿集, 2003年05月 - 人工心臓用アキシャル型磁気浮上遠心ポンプの改良
村上倫子; 増澤徹; 小沼弘幸; 児嶋次郎; 岡田養二
電気学会研究会資料, 2003年05月 - Design of a self-bearing slice motor for a centrifugal blood pump
Satoshi Ueno; Chen Chen; Tetsuo Ohishi; Ken-ichi Matsuda; Yohji Okada; Yoshiyuki Taenaka; Toru Masuzawa
the Sixth international symposium on magnetic bearings, 1998年08月
所属学協会
- 2017年01月 - 現在, International Society for Mechanical Circulatory Support
- 2007年11月 - 現在, 日本AEM学会
- 2014年06月 - 2020年05月, International Federation for Artificial Organs
- 2014年04月 - 2020年03月, 日本学術会議
- 2016年12月, International Society for Rotary Blood Pump
- 2013年09月, アジア太平洋人工臓器学会
- 2008年, 日本AEM学会
- 日本人工臓器学会
- ライフサポート学会
- 精密工学会
- 日本機械学会
- 米国人工臓器学会
- 日本生体医工学会
- 日本生活支援工学会
- 電気学会
- 計測自動制御学会
共同研究・競争的資金等の研究課題
産業財産権
- 特許第5963134号, 特願2012-172943, アキシャル型磁気浮上モータ
増澤徹,長真啓 - 特願2015-167656, 磁気浮上姿勢制御装置
増澤徹, 國府田芳彰 - 5636857, 特願2010-229738, 生体組織接着用柔軟性金属箔テープ及びその接着方法
尾関和秀,増澤徹,岸田晶夫,加藤綾子 - 特許第5590520号, 特願2009-132239, アキシャル型磁気浮上モータおよびアキシャル型磁気浮上モータを備えたアキシャル型磁気浮上遠心ポンプ
増澤徹 - 特願2014-159157, 陰圧発生防止機構及びその陰圧発生防止機構を備えた容積ポンプ
増澤徹,黒崎亘 - 5543435, 2011-510193, 生体組織と人工物の接着装置,ステント
増澤徹,尾関和秀,岸田晶夫,加藤綾子 - 第5509436号, 特願2009-8336, 遠心型の補助人工心臓を用いた体内発電装置
山家智之,白石泰之,福長一義,磯山隆,増澤徹,岡本英治 - 5465249, PCT出願, 磁気浮上制御装置およびハイブリッド型磁気軸受け
増澤徹,佐々木瑛祐 - 5462530, PCT/JP2010/059375, 発熱装置及び生体組織接着装置
岸田晶夫,増澤徹,樋上哲哉 - 豪国特許第2010272054号, Magnetic levitation control device and hybrid type magnetic bearing
増澤徹, 佐々木瑛祐 - 5408707, 特願2009-113579, ポンプ装置
増澤徹,佐々木瑛祐 - PCT/JP2013/063880, 組織自己接合型体内挿入管及び該体内挿入管との接合方法
増澤徹,青代敏行 - 特願2012-111902, 組織自己接合型体内挿入管及び該体内挿入管との接合方法
増澤徹,青代敏行 - 5028607, 特願2006-055619, 生体組織接着装置
岸田晶夫 増澤徹 樋上哲哉 - 特願2011-246111, ローレンツモータ
増澤徹,一ノ瀬高紀,ウルリッヒ・スタインセイファー - 4786297, 特願2005-188588, ハイブリッド型磁気軸受
増澤徹 - 4666335, 特願2002-259269, 機械的振動による生物機能の制御方法とその装置
岸田晶夫 小薗勉 宮崎幸造 増澤徹 - PCT出願 PCT/JP2007/053969, 生体組織と人工物の接着物の接着方法及びその接着装置
- PCT/AU2010/000428, Heart pump controller
Masuzawa Toru, Eisuke Sasaki, Daniel Timms - 特願2009-167937, ハイブリッド型磁気軸受け
増澤徹,佐々木瑛祐 - 特願2009-102468, 生体組織と人工物の接着物の接着方法及びその接着装置
増澤徹,尾関和秀,岸田晶夫,加藤綾子 - 特願2008-333647, 人工心筋装置
山家智之,白石泰之,福井康裕,阿部祐輔,増澤徹,岡本英治 - 特許第4153468号, 特願2004-190147, 磁気浮上型モータ及びターボポンプ
増澤徹 - 特許第4106484号, 特願2002-14882, 動圧軸受け付き磁気浮上ポンプ
山根隆志 岡田養二 増澤徹 小西義昭 - 特許第3930834号, 特願2003-184874, アキシャル型磁気浮上回転機器及び遠心ポンプ
増澤徹 岡田養二 - 特願2006-055620, 生体組織接着性医療器具
岸田晶夫,樋上哲哉,増澤徹 - 特願2006-223106, 永久磁石を用いたハイブリット型磁気軸受
岡田養二 増澤徹 中山直久 - 特許第3808811号, 特願2002-228126, アキシャル磁気浮上回転モータおよびこれを用いた回転機器
増澤徹 岡田養二 - 特許公開2007-04425, 褥瘡予防エアマット及びそのエアマットに用いられるロータリーバルブ又は車椅子
宮入睦彦,増澤徹 - 特願2004-011456, 位置・傾斜計測装置
木村孝之 増澤徹 - 特願2003-417956, ベッドおよびベッドに使用される床ずれ防止装置
増澤徹 吉澤卓 永井文秀 平田敬一 - 特開2001-252351, 特願2000-65057, 血液ポンプ
増澤徹 岡田養二 - 特開2001-252351, 特願2000-65057, 血液ポンプ
増澤徹 岡田養二 - 特許番号第2588753号, 特開平1-308941, 特願昭63-139433, 粘度計測装置
- 特許番号第2520047号, 特開平4-161139, 特願平2-285768, 患者監視システム
福井康裕 河村剛史 坂牧孝規 伊藤孝 熊谷伸吾 増澤徹 安田一 - 特開平7-136247, 特願平5-286359, 血液用遠心ポンプ
高野久輝 妙中義之 荒木賢二 近成賢一 増澤徹 - PCT/JP2010/002828, 生体組織と人工物の接着装置,ステント
増澤徹,尾関和秀,岸田晶夫,加藤綾子
社会貢献活動
- 〔主要な業績〕NPO医工連携推進機構 理事長
運営参加・支援
2024年06月01日 - 現在 - 〔主要な業績〕NPOオーファンデバイス研究開発 理事長
運営参加・支援
2023年02月22日 - 現在 - 〔主要な業績〕NPO医工連携推進機構 理事
運営参加・支援
2007年04月01日 - 2025年03月31日 - 〔主要な業績〕日本学術会議 連携会員
その他
日本学術会議, 2014年04月01日 - 2024年03月31日 - 〔主要な業績〕令和3年度国立研究開発法人日本医療研究開発機構委託事業,令和3年度 医療機器等における先進的研究開発・開発体制強靱化事業(医療機器等に関する開発ガイドライン(手引き)策定事業),経皮的エネルギー伝送システム 開発WG座長
司会
令和3年度国立研究開発法人日本医療研究開発機構委託事業, 2021年04月01日 - 2022年03月31日 - 令和2年度国立研究開発法人日本医療研究開発機構委託事業,令和2年度 医療機器等における先進的研究開発・開発体制強靱化事業(医療機器等に関する開発ガイドライン(手引き)策定事業),経皮的エネルギー伝送システム 開発WG座長
司会
令和2年度国立研究開発法人日本医療研究開発機構委託事業, 2020年04月01日 - 2021年03月31日 - 〔主要な業績〕「次世代型補助循環システムの評価方法」ワーキンググループ
助言・指導
国立循環器病研究センター, 2014年04月01日 - 2018年03月31日 - 〔主要な業績〕専門調査員
調査担当
文部科学省科学技術・学術政策研究所科学技術動向研究センター, 2012年05月02日 - 2013年03月31日