記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1111/aor.14380

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： https://doi.org/10.1142/S0219519422500075

掲載種別：研究論文（学術雑誌）  

To develop a power generation system as a solution to the power supply problems of small active implantable medical devices, we proposed a new method to examine muscles using skeletal muscle contraction through electrical stimulation. Realization of the system requires data on the contraction characteristics of a part of the muscles through which blood flows; thus, a dedicated setup was built and verified using a goat. The connecting parts were attached to two points in the large muscle of the goat's trunk; one was fixed and the other slid along the guide. The distance and force between the two points, approaching each other, were measured by contracting the muscle between the points using electrical stimulation and pulling the measurement cart. The contraction distance and force were measured simultaneously, and the dynamic work of the contraction was calculated. The muscle work occurred with almost the same time delay regardless of the load, and the work tended to be greater when the contraction force, and not the contraction distance, of the muscle was large. The setup is physiological, simple, and versatile. Our setup can potentially be used in the development of implantable power generation systems and in other related fields.

DOI： 10.1142/S0219519422500075

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： https://doi.org/10.1016/j.ejvsvf.2022.01.004

記述言語：英語   掲載種別：研究論文（学術雑誌）  

In this study, we developed a trans-valve left ventricular assist device (LVAD) that unites a rear-impeller axial-flow blood pump (AFBP) and a polymer membrane valve placed at the aortic valve position. The diameter and length of the rear impeller AFBP was 12 and 63 mm, respectively. The polymer membrane valve was similar to the jelly-fish valve consisting of a valve leaflet made of silicone rubber (thickness 0.5 mm), valve ring (diameter: 25 mm), and valve spokes. The trans-valve LVAD was examined in a mock circulation. An implantable pulsatile flow (PF) VAD was connected to an atrial reservoir to simulate the left ventricle (LV), and the Hall valve was worn in the inflow port, and the trans-valve LVAD was placed in the outflow port as an outflow valve. When the motor rotational speed increased to 26 400 rpm, the mean aortic flow increased from 4.2 to 5.3 L/min, mean aortic pressure increased from 83.4 to 100 mm Hg, and mean motor current of the implantable PF VAD decreased from 1.18 to 0.94 A (unloading effect on LV −21%). The energy equivalent pressure increased from 85.2 to 102 mm Hg, and surplus hemodynamic energy (SHE) decreased by −15.4% from the baseline. In conclusion, the trans-valve LVAD has an advantage of preserving pulsatility without any complicated mechanism and is a novel and promising LV support device.

DOI： doi.org/10.1111/aor.13687

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Objective: There is a need for small diameter vascular substitutes in the absence of available autologous material. A small diameter, long tissue engineered vascular graft was developed using a completely autologous approach called "in body tissue architecture technology (iBTA)". The aim of this pilot study was to evaluate "Biotubes", iBTA induced autologous collagenous tubes, for their potential use as small diameter vascular bypass conduits. Methods: Biotubes (internal diameter 4 mm, length 50 cm, wall thickness 0.85 mm) were prepared by subcutaneous embedding of plastic moulds (Biotube Maker) in three goats for approximately two months. Allogenic Biotubes (length 10 cm [n = 2], 15 cm [n = 2], 22 cm [n = 2]) were bypassed to both carotid arteries by end to side anastomosis with their ligation between the anastomoses in another three goats. Residual Biotubes were examined for their mechanical properties. After four weeks, the harvested Biotubes were evaluated histologically. Results: All Biotubes had sufficient pressure resistance, approximately 3000 mmHg. Although wall thickening occurred at two proximal anastomosis sites, all six grafts were patent without luminal thrombus formation, stenosis, or aneurysm deformation throughout the implantation period. Endothelial cells covered both anastomosis sites almost completely, with partial covering in the central portion of the grafts. Furthermore, α smooth muscle actin positive cells infiltrated the middle layer along almost the entire graft length. Conclusion: This preliminary study showed that small diameter, long, tissue engineered Biotubes could function properly as arterial bypass conduits in a large animal for one month without any abnormal change in vascular shape. Thus, small diameter, long Biotubes are potentially viable conduits, which are biocompatible and labour non-intensive, and therefore, suitable for clinical practice. Additionally, Biotubes can start the regeneration process in a short period of time.

DOI： 10.1016/j.ejvsvf.2022.01.004

PubMed

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

DOI： 10.1109/EMBC46164.2021.9629561

担当区分：筆頭著者   記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： https://doi.org/10.11239/jsmbe.Annual59.330

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： https://doi.org/10.11239/jsmbe.Annual59.579

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

担当区分：筆頭著者   記述言語：日本語   掲載種別：研究論文（その他学術会議資料等）  

担当区分：責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： https://doi.org/10.1299/jsmedmc.2021.542

担当区分：筆頭著者   記述言語：日本語   掲載種別：研究論文（その他学術会議資料等）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

In traditional Chinese pulse diagnosis, the pulses of bilateral radial arteries are palpated by three fingers. In this study, a device that can objectively perform pulse diagnosis using multiple pressure sensors with a cuff was developed. The device has three pressure sensors in series and a cuff to apply external pressure load. Pulse waves were measured using the non-invasive pulse diagnostic device. The relationship of the data obtained from the proposed system with the diagnosis by the traditional method was examined. The study was conducted with the approval of the Ethics Committee in Tohoku University. Twelve adult male subjects were studied. Data of pulse waveforms recorded from the pulse diagnosis device, electrocardiogram, and continuous blood pressure measured at the fingertip were stored and analyzed. The pulse waves of the subjects were categorized as middle pulse, floating pulse, or sunken pulse according to pulse diagnosis in traditional Chinese medicine. Pulse–waveform data were obtained to measure the pulse–pressure changes, which showed different patterns of the rise time at the three measurement sites. Envelope analysis of the pulse waveform from the middle sensor revealed that the peak value of the pulse pressure increased during calculation stress compared to the resting state. It was possible to measure the pulse waves even when a higher external pressure was applied. Objective pulse-wave measurement using a method similar to that in traditional pulse diagnosis was realized, and pulse waveforms were measured using the proposed pulse diagnosis system.

DOI： 10.14326/abe.10.113

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Chronic blood trauma caused by the shear stresses generated by mechanical circulatory support (MCS) systems is one of the major concerns to be considered during the development of ventricular assist devices. Large multimers with high-molecular-weight von Willebrand factor (VWF) are extended by the fluid forces in a shear flow and are cleaved by ADAMTS13. Since the mechanical revolving motions in artificial MCSs induce cleavage in large VWF multimers, nonsurgical bleeding associated with the MCS is likely to occur after mechanical hemodynamic support. In this study, the shear stress (~ 600 Pa) and exposure time related to hemolysis and VWF degradation were investigated using a newly designed mechanical shuttle shear flow tester. The device consisted of a pair of cylinders facing the test section of a small-sized pipe; both the cylinders were connected to composite mechanical heads with a sliding-sleeve structure for axial separation during the withdrawing motion. The influence of exposure time, in terms of the number of stress cycles, on hemolysis and VWF degradation was confirmed using fresh goat blood, and the differences in the rates of dissipation of the multimers were established. The plasma-free hemoglobin levels showed a logarithmic increase corresponding to the number of cycles, and the dissipation of large VWF multimers occurred within a few seconds under high shear stress flow conditions.

DOI： 10.1007/s10047-020-01219-3

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Extracorporeal membrane oxygenation (ECMO) plays an important role in the coronavirus disease 2019 (COVID-19) pandemic. Management of thrombi in ECMO is generally an important issue; especially in ECMO for COVID-19 patients who are prone to thrombus formation, the thrombus formation in oxygenators is an unresolved issue, and it is very difficult to deal with. To prevent thromboembolic complications, it is necessary to develop a method for early thrombus detection. We developed a novel method for detailed real-time observation of thrombi formed in oxygenators using indocyanine green (ICG) fluorescence imaging. The purpose of this study was to verify the efficacy of this novel method through animal experiments. The experiments were performed three times using three pigs equipped with veno-arterial ECMO comprising a centrifugal pump (CAPIOX SL) and an oxygenator (QUADROX). To create thrombogenic conditions, the pump flow rate was set at 1 L/min without anticoagulation. The diluted ICG (0.025 mg/mL) was intravenously administered at a dose of 10 mL once an hour. A single dose of ICG was 0.25mg. The oxygenator was observed with both an optical detector (PDE-neo) and the naked eye every hour after measurement initiation for a total of 8 hours. With this dose of ICG, we could observe it by fluorescence imaging for about 15 minutes. Under ICG imaging, the inside of the oxygenator was observed as a white area. A black dot suspected to be the thrombus appeared 6-8 hours after measurement initiation. The thrombus and the black dot on ICG imaging were finely matched in terms of morphology. Thus, we succeeded in real-time thrombus detection in an oxygenator using ICG imaging. The combined use of ICG imaging and conventional routine screening tests could compensate for each other's weaknesses and significantly improve the safety of ECMO.

DOI： 10.1111/aor.13999

記述言語：英語   掲載種別：研究論文（学術雑誌）  

In roller pumps used for cardiopulmonary bypass (CPB), the degree of blockage within the tube resulting from compression of the tube by the rollers, or the degree of occlusion, is closely related to hemolysis, with both tight occlusive and non-occlusive degrees promoting hemolysis. There are as yet no international standards regarding methods of adjusting occlusiveness, and the amount of mechanical stress exerted upon blood remains unknown. To prevent hemolysis during CPB using roller pumps, there is a need to clarify and quantitatively assess the mechanical stress of the occlusiveness of the roller pump. In this study, we have developed a degree of occlusion quantification system which constructs the flow channel shape within an occluded tube from red optical density images, and we have verified the validity of this system. Utilizing a linear actuator, an acrylic roller and raceway, a solution colored with simulated blood powder, and a 3/8-inch vinyl chloride tube, this system uses a camera to capture red optical density images within an occluded tube and constructs the tube flow channel shape using a formula manipulation system. To verify the accuracy of this system, we compared the thickness of a cross-section of the flow channel constructed with the degree of occlusion quantification system with the thickness of a cross-section of silicone cured under the same occlusion conditions. Our experiments indicated that for areas with a small tube gap, this system can construct highly accurate three-dimensional shapes and obtain quantitative indicators assessing the degree of occlusion.

DOI： 10.1007/s10047-020-01211-x

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

In roller pumps used for cardiopulmonary bypass (CPB), the degree of blockage within the tube resulting from compression of the tube by the rollers, or the degree of occlusion, is closely related to hemolysis, with both tight occlusive and non-occlusive degrees promoting hemolysis. There are as yet no international standards regarding methods of adjusting occlusiveness, and the amount of mechanical stress exerted upon blood remains unknown. To prevent hemolysis during CPB using roller pumps, there is a need to clarify and quantitatively assess the mechanical stress of the occlusiveness of the roller pump. In this study, we have developed a degree of occlusion quantification system which constructs the flow channel shape within an occluded tube from red optical density images, and we have verified the validity of this system. Utilizing a linear actuator, an acrylic roller and raceway, a solution colored with simulated blood powder, and a 3/8-inch vinyl chloride tube, this system uses a camera to capture red optical density images within an occluded tube and constructs the tube flow channel shape using a formula manipulation system. To verify the accuracy of this system, we compared the thickness of a cross-section of the flow channel constructed with the degree of occlusion quantification system with the thickness of a cross-section of silicone cured under the same occlusion conditions. Our experiments indicated that for areas with a small tube gap, this system can construct highly accurate three-dimensional shapes and obtain quantitative indicators assessing the degree of occlusion.

DOI： 10.1007/s10047-020-01211-x

PubMed

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

Chronic blood trauma caused by the shear stresses generated by mechanical circulatory support (MCS) systems is one of the major concerns to be considered during the development of ventricular assist devices. Large multimers with high-molecular-weight von Willebrand factor (VWF) are extended by the fluid forces in a shear flow and are cleaved by ADAMTS13. Since the mechanical revolving motions in artificial MCSs induce cleavage in large VWF multimers, nonsurgical bleeding associated with the MCS is likely to occur after mechanical hemodynamic support. In this study, the shear stress (~ 600 Pa) and exposure time related to hemolysis and VWF degradation were investigated using a newly designed mechanical shuttle shear flow tester. The device consisted of a pair of cylinders facing the test section of a small-sized pipe; both the cylinders were connected to composite mechanical heads with a sliding-sleeve structure for axial separation during the withdrawing motion. The influence of exposure time, in terms of the number of stress cycles, on hemolysis and VWF degradation was confirmed using fresh goat blood, and the differences in the rates of dissipation of the multimers were established. The plasma-free hemoglobin levels showed a logarithmic increase corresponding to the number of cycles, and the dissipation of large VWF multimers occurred within a few seconds under high shear stress flow conditions.

DOI： 10.1007/s10047-020-01219-3

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出版者・発行元：Springer International Publishing  

DOI： 10.1007/978-3-030-66169-4_11

CiNii Research

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その他リンク： https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-19K18021/

掲載種別：研究論文（学術雑誌）   出版者・発行元：Japanese Society for Medical and Biological Engineering  

DOI： 10.14326/abe.10.113

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

In this study, we developed a trans-valve left ventricular assist device (LVAD) that unites a rear-impeller axial-flow blood pump (AFBP) and a polymer membrane valve placed at the aortic valve position. The diameter and length of the rear impeller AFBP was 12 and 63 mm, respectively. The polymer membrane valve was similar to the jelly-fish valve consisting of a valve leaflet made of silicone rubber (thickness 0.5 mm), valve ring (diameter: 25 mm), and valve spokes. The trans-valve LVAD was examined in a mock circulation. An implantable pulsatile flow (PF) VAD was connected to an atrial reservoir to simulate the left ventricle (LV), and the Hall valve was worn in the inflow port, and the trans-valve LVAD was placed in the outflow port as an outflow valve. When the motor rotational speed increased to 26 400 rpm, the mean aortic flow increased from 4.2 to 5.3 L/min, mean aortic pressure increased from 83.4 to 100 mm Hg, and mean motor current of the implantable PF VAD decreased from 1.18 to 0.94 A (unloading effect on LV -21%). The energy equivalent pressure increased from 85.2 to 102 mm Hg, and surplus hemodynamic energy (SHE) decreased by -15.4% from the baseline. In conclusion, the trans-valve LVAD has an advantage of preserving pulsatility without any complicated mechanism and is a novel and promising LV support device.

DOI： 10.1111/aor.13687

PubMed

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

In roller pumps used for cardiopulmonary bypass (CPB), the degree of blockage within the tube resulting from compression of the tube by the rollers, or the degree of occlusion, is closely related to hemolysis, with both tight occlusive and non-occlusive degrees promoting hemolysis. There are as yet no international standards regarding methods of adjusting occlusiveness, and the amount of mechanical stress exerted upon blood remains unknown. To prevent hemolysis during CPB using roller pumps, there is a need to clarify and quantitatively assess the mechanical stress of the occlusiveness of the roller pump. In this study, we have developed a degree of occlusion quantification system which constructs the flow channel shape within an occluded tube from red optical density images, and we have verified the validity of this system. Utilizing a linear actuator, an acrylic roller and raceway, a solution colored with simulated blood powder, and a 3/8-inch vinyl chloride tube, this system uses a camera to capture red optical density images within an occluded tube and constructs the tube flow channel shape using a formula manipulation system. To verify the accuracy of this system, we compared the thickness of a cross-section of the flow channel constructed with the degree of occlusion quantification system with the thickness of a cross-section of silicone cured under the same occlusion conditions. Our experiments indicated that for areas with a small tube gap, this system can construct highly accurate three-dimensional shapes and obtain quantitative indicators assessing the degree of occlusion.

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：Institute of Electrical and Electronics Engineers Inc.  

Rotary blood pump (RP) is one of the most important devices in the treatment of profound heart failure and is known to reduce the pulse in the blood pressure waveform, especially when it is used for axial flow. In an outpatient clinic, checking the pulse of a patient implanted with an RP can help diagnose the patient's condition. For that purpose, animal experiments with healthy adult goats implanted with the EVAHEART system were carried out after obtaining ethical committee approval. Visual imaging of the goats' faces was recorded using a video camera. The pulse waves were clearly recorded using the newly developed pulse diagnosis system with video imaging and compared with laser Doppler flowmeter and time series data. Spectral analysis of the time series data showed the usefulness of video imaging from outside the body. Clinical applications are planned, and this newly developed method is expected to be a useful diagnostic method for evaluating the cardiac function in patients implanted with RPs in the future.

DOI： 10.1109/EMBC44109.2020.9175425

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：Institute of Electrical and Electronics Engineers Inc.  

With the progress of surgical technology, the survival rate after resection of esophageal and tongue carcinomas has improved. However, the surgical protocol for esophageal and tongue surgery is complex, and surgery for elderly esophageal and tongue carcinoma patients with cardiopulmonary dysfunction is difficult. Using an artificial tongue and esophagus will be helpful for patients. However, peristalsis of foods depends on food size, taste, and viscosity. This study developed and evaluated a new diagnosis machine for drinking and peristalsis motion. Before clinical evaluation, animal experiments were performed on healthy adult goats using a stereo camera. After a feasibility study of the diagnosis system for peristalsis, clinical evaluation was conducted on healthy normal volunteers. We observed no aspiration pneumonia. The foods and drinks tested were safe. There was no mis-swallowing, but the participants' feeling with regard to taste differed. Overall, the results indicated that the quantitative swallowing and peristalsis diagnosis system is safe. Evaluation of the visual imaging and spectral analysis gave us useful information about peristalsis, which will help us design an artificial tongue and esophagus with a good control mechanism in the near future.

DOI： 10.1109/EMBC44109.2020.9176039

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記述言語：日本語   出版者・発行元：(一社)日本人工臓器学会  

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担当区分：筆頭著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

We previously reported the development of a new hybrid medical material comprising bio-based materials with high biocompatibility and artificial materials with characteristics of excellent strength and processability. This material shows sufficient biocompatibility and excellent stability in vivo. Moreover, when applied to the surface of an implantable sensor, the biological reaction on the sensor function surface can be well controlled. For commercialization and widespread use of hybrid materials with such superior properties, sterilization and storage are critical considerations, given that hybrid materials must be processed outside the body prior to application as medical materials in vivo, thus posing a risk of contamination despite best efforts. Therefore, the aim of the present study was to establish an optimal sterilization method that will not impair the biocompatibility of the hybrid material. Toward this end, we tested six sterilization methods for the hybrid material: autoclave (121℃, 20 min), dry heat (160℃, 120 min), ethylene oxide gas (37℃, 120 min), hydrogen peroxide plasma (45℃, 45 min), and gamma ray (25 kGy) with and without lyophilization. After sterilization, the material was cultured with vascular endothelial cells to evaluate the engraftment rate, and was observed with light and scanning electron microscopy to determine shape and structure changes. The results demonstrated that gamma sterilization without lyophilization was the best sterilization method for this material, which preserved the collagen network and showed no change in number of adhered vascular endothelial cells compared to the pre-sterilized material. These findings are useful to promote the commercialization of this hybrid material with combined advantages of synthetic and bio-based materials for widespread clinical application in the engineering of artificial organs.

DOI： doi.org/10.14326/abe.9.83

記述言語：日本語   出版者・発行元：公益社団法人 日本生体医工学会  

<p>人工心肺用ローラポンプ使用時における溶血リスク軽減のために、ローラポンプ圧閉度の定量評価が求められている。我々は、機械的ストレス算出に必要となるチューブ内の流路形状を赤色濃淡画像から可視化するシステムを開発した。このシステムは、リニアアクチュエータ、アクリルで作製したローラとレースウェイ、模擬血液粉末で着色した溶液、3/8 インチの塩化ビニルチューブを用い、圧閉されたチューブ内赤色濃淡画像をカメラで撮影し、数式処理システムにて流路形状を構築するシステムである。本研究では、圧閉度可視化システムの精度を評価するために、赤色濃淡画像から計測された流路断面の厚みと、同じ圧閉条件下にて硬化させた高精細転写用シリコーン断面の厚みを比較した。なお、硬化させたシリコーンは3次元形状測定機にて測定した。実験の結果より、可視化システムで計測された流路断面の厚みとシリコーンの厚みを比較すると、流路断面形状がよく近似でき、線形関係が得られた厚み領域で示されることがわかった。ただし、流路断面の厚みが120 μｍ以上の場合、赤色濃淡画像から推定された流路断面形状はシリコーン転写3次元形状と比べて低値を示した。これらのことから、本システムでは圧閉されたチューブ内の狭小流路については高精度の3次元形状を構築できると考えられた。</p>

DOI： 10.11239/jsmbe.Annual58.266

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記述言語：日本語   出版者・発行元：公益社団法人 日本生体医工学会  

<p>医療生体情報は安静状態か拘束された制約下での計測が必須の条件となっているが、計測時の環境が与える計測結果への悪影響は不可避なものとして黙認されている。非接触センサの開発も行われているが、感度や精度が低いことに加え、特定の範囲内でのみ計測が可能になるなど、包括的な解決にならない事が課題である。これまでの研究により装着感の小さい接触型センサの開発を進めてきた。これらの装着感の少ないセンサをひとつのデバイスとして統合し、これまで同時に計測することができなかった生体情報（脈拍・心電図・体温分布・体動）をひとつの衣服から得ることが可能となるスマートテキスタイルの開発を行う。スマートテキスタイルは既存のウェアラブルデバイスが持つ制約から解放する外乱のない計測結果を得られるだけでなく、これまで安定計測できなかった睡眠・食事・運動時などあらゆる場面で生体情報を取得することを可能とするものである。装着感を評価する方法で一般的な手法は、主観的な評価が主であり一般性と定量性が欠けていることが課題である。そこで、デバイスが生体に与えるストレスを循環生理学的に定量的に評価することで、装着感のない新しいセンサ開発を行う。本研究により作製したスマートテキスタイルを用いることで、全生活時間のビッグデータを取得しこの情報を元に新たな医療機器・ヘルスケアデバイスを開発することが最終的な目標である。</p>

DOI： 10.11239/jsmbe.Annual58.409

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記述言語：日本語   出版者・発行元：(一社)日本人工臓器学会  

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

In this study, rear-impeller axial flow blood pumps (RIAFBP) were developed to realize a trans-valve axial ventricular assist device (VAD) which consists of the latter blood pump and a polymer monomembrane aortic valve, such as the jellyfish valve. The motor of the RIAFBP is installed in the left ventricle, and its impeller is placed at the aortic valve position. In the prototype RIAFBP, the rotation of the motor is sustained by polyethylene bushings. The RIAFBP has a length of 50 mm and diameter of 19.6 mm. The miniature RIAFBP has the same construction as that of the prototype; however, it employs a ceramic bearing and fin bearing to improve endurance and to reduce blood stagnation. The miniature RIAFBP has a length of 63 mm and diameter of 12 mm. Both RIAFBPs were examined by an in vitro experiment using a 33% glycerin solution. The prototype RIAFBP achieved a maximum pump outflow of 8.5 L/min against a pump head of 100 mm Hg at a rotational speed of 12 000 rpm. The miniature RIAFBP achieved 7 L/min against a pump head of 70 mm Hg at a rotational speed of 21 600 rpm. In conclusion, the miniature RIAFBP has enough pump performance to realize the trans-valve axial VAD.

DOI： 10.1111/aor.13476

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：Institute of Electrical and Electronics Engineers Inc.  

Your heart rate and blood pressure are respond to the curve, slope, lane width, and road surface friction coefficient of the expressway design. However, no report was reported concerning about the Expressway design from the viewpoint of medical information of the driver until now. To prevent the traffic accident, human factor is of course one of the most important factors. In this study, the Cloud Database Construction for the Expressway Design by the use of the Medical Information had been tried to carry out. HR response and PWV responses had been tried to be analyzed by the sensors in the car during driving. LF, HF and LF/HF of Heart rate variability had been calculated and tagged with expressway information including left and right curve, slope, lane width, and road surface friction coefficient. Furthermore, pulse of the descending aorta had been tried to be recorded from the sensor in a driver seat, so, the pulse wave velocity and blood pressure could be evaluated. Recording system of an Eye movement, pupil diameter, cerebral blood flow, and EEG are now under construction. So, all human driver's data will be combined in the Cloud of the Central office. this method will be useful for the development of the designing method the Expressway in near future.

DOI： 10.1109/EMBC.2019.8856546

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

記述言語：日本語   出版者・発行元：公益社団法人 日本生体医工学会  

<p>医療生体情報は安静状態か拘束された制約下での計測が必須であり、計測時の環境が与える計測結果への影響は必要悪として無視されている。我々は装着感のない接触型センサを開発しており、計測による制約から解放することで外乱のない計測結果を得られるだけでなく、これまで安定計測できなかった睡眠・食事・運動時などあらゆる場面で生体情報を取得することを目的するものである。開発したシステムと既存のセンサとで生体に与えるストレス影響を循環生理学的に比較してその装着感を定量的に評価する。本研究により全生活時間のビッグデータを取得し、この情報を元に新たな医療機器・ヘルスケアデバイスを開発することが最終目標である。本発表では、3つの拠点で実施した、筋電・心電・温度・心拍を対象としたセンサの開発と装着感の評価に関する報告を行う。</p>

DOI： 10.11239/jsmbe.Annual57.S36_2

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記述言語：日本語   出版者・発行元：公益社団法人 日本生体医工学会  

生体医工学治療が支える少子高齢社会においては、重篤な疾患治療に対する医療機器開発応用を迅速に進めるとともに、安全性有効性に関する科学的根拠に基づく評価を非臨床で進める必要がある。東北大学加齢医学研究所非臨床試験推進センターでは、全国共同利用共同研究施設として植込み型補助人工心臓を例として長期動物実験をはじめ、生体医工学に関連する基盤技術を応用して生体適合性および血行力学的有効性の評価を行ってきている。ヒト臨床試験に先立って行われる非臨床動物試験評価では、ヒトまたは患者機能の代替とおいて動物試験が行われるが、種別による差の他にも個体差や環境要因、個々の計測誤差要因を含む収集データ精度を補償することが極めて重要である。本報告では、植込み型人工臓器と補助循環治療を例として血行動態評価に関する非臨床医工学モデリング手法と、モデリングにおけるエンティティへの種種アプローチ手法によるモダリティ評価について提示する。またあわせて一貫したデータ管理アクセスの試みについて紹介する。

DOI： 10.11239/jsmbe.annual57.s220_1

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Nature Publishing Group  

The newly developed radioisotope-free technique based on magnetic nanoparticle detection using a magnetic probe is a promising method for sentinel lymph node biopsy. In this study, a novel handheld magnetic probe with a permanent magnet and magnetic sensor is developed to detect the sentinel lymph nodes in breast cancer patients. An outstanding feature of the probe is the precise positioning of the sensor at the magnetic null point of the magnet, leading to highly sensitive measurements unaffected by the strong ambient magnetic fields of the magnet. Numerical and experimental results show that the longitudinal detection length is approximately 10 mm, for 140 μg of iron. Clinical tests were performed, for the first time, using magnetic and blue dye tracers-without radioisotopes-in breast cancer patients to demonstrate the performance of the probe. The nodes were identified through transcutaneous and ex-vivo measurements, and the iron accumulation in the nodes was quantitatively revealed. These results show that the handheld magnetic probe is useful in sentinel lymph node biopsy and that magnetic techniques are widely being accepted as future standard methods in medical institutions lacking nuclear medicine facilities.

DOI： 10.1038/s41598-018-19480-1

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1126/sciadv.aau2426

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1038/s41598-018-19480-1

記述言語：英語   掲載種別：研究論文（学術雑誌）  

© 2018 The Authors. High-precision monitoring of electrophysiological signals with high spatial and temporal resolutions is one of the most important subjects for elucidating physiology functions. Recently, ultraflexible multielectrode arrays (MEAs) have been fabricated to establish conformal contacts with the surface of organs and to measure propagation of electrophysiological signals with high spatial-temporal resolution; however, plastic substrates have high Young's modulus, causing difficulties in creating appropriate stretchability and blood compatibility for applying them on the dynamically moving and surgical bleeding surface of the heart. Here, we have successfully fabricated an active MEA that simultaneously achieves nonthrombogenicity, stretchability, and stability, which allows long-term electrocardiographic (ECG) monitoring of the dynamically moving hearts of rats even with capillary bleeding. Because of the active data readout, the measured ECG signals exhibit a high signal-to-noise ratio of 52 dB. The novel stretchable MEA is carefully designed using state-of-the-art engineering techniques by combining extraordinarily high gain organic electrochemical transistors processed on microgrid substrates and a coating of poly(3-methoxypropyl acrylate), which exhibits significant antithrombotic properties while maintaining excellent ionic conductivity.

DOI： 10.1126/sciadv.aau2426

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担当区分：筆頭著者   記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

担当区分：筆頭著者   記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

記述言語：英語  

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記述言語：日本語   掲載種別：研究論文（その他学術会議資料等）  

記述言語：日本語  

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

記述言語：日本語  

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1038/s41598-017-10115-5

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：NATURE PUBLISHING GROUP  

Compromised circulation is a potential complication during the postoperative period following tissue transplantation. The use of a monitoring device allows physicians to detect compromised circulation immediately. Such monitoring devices need to be continuously usable, wearable, and area-detectable. However, existing devices fail to satisfy all of these requirements simultaneously. We developed a wearable, multipoint pulse wave-monitoring device. An array of reflective optical sensors implemented on a thin film substrate was used as a lightweight and flexible probe. As a model of tissue transplantation, an inguinal flap in a Wistar rat was dissected and freed from all subcutaneous tissue. By ligating the artery or vein, ischemia or congestion was induced in the tissue. In a human study, ischemia or congestion was induced in the palm by pressing the feeding artery or cutaneous vein, respectively. The amplitude of the pulse wave was evaluated using the power spectrum of Fourier transformed signals. Pulse wave amplitude significantly decreased under compromised circulation in both animal and human models. Moreover, we accomplished 1 week of continuous wireless monitoring in healthy subjects. These results demonstrated the potential utility of the developed device in postoperative blood-flow monitoring to improve the rescue rate of transplanted tissue.

DOI： 10.1038/s41598-017-10115-5

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：SPRINGER  

There are recent reports of hybrid tissue-fabric materials with good performance-high biocompatibility and high mechanical strength. In this study, we demonstrate the capability of a hybrid material as a long-term filter for blood proteins. Polyester fabrics were implanted into rats to fabricate hybrid tissue-fabric material sheets. The hybrid materials comprised biological tissue grown on the fabric. The materials were extracted from the rat's body, approximately 100 days post-implantation. The tissues were decellularized to prevent immunological rejection. An antithrombogenicity test was performed by dropping blood onto the hybrid material surface. The hybrid material showed lesser blood coagulation than polysulfone and cellulose. Blood plasma was filtered using the hybrid material to evaluate the protein removal percentage and the lifetime of the hybrid material in vitro. The hybrid material showed a comparable performance to conventional filters for protein removal. Moreover, the hybrid material could work as a protein filter for 1 month, which is six times the lifetime of polysulfone.

DOI： 10.1007/s10439-016-1781-5

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：WILEY-BLACKWELL  

Histopathological analysis can provide important information in long-term experiments with total artificial heart (TAH). Recently, a new type of blood pump, the helical flow total artificial heart (HF-TAH) was developed. This study aimed to investigate the changes in selected vital organs in animal experiments with implanted HF-TAH. Samples from lung, liver, and kidneys from two female goats (No. 1301 and No. 1304) with implanted HF-TAH were analyzed. Tissue samples were fixed in 10% formaldehyde and 4 mm thick transverse sections were stained with hematoxylin-eosin (HE). Additional staining was done for detection of connective tissue (Masson-Goldner stain) and for detection of iron (hemosiderin) deposits (Perls stain). Sections were scanned at 1003 and 5003 magnification with a light microscope. Experiment no. 1301 survived 100 days (cause of termination was heavy damage of the right pump); experimental goat no. 1304 survived 68 days and was sacrificed due to severe right hydrodynamic bearing malfunction. Histopathological analysis of liver samples proved signs of chronic venostasis with limited focal necrotic zones. Dilated tubules, proteinaceous material in tubular lumen, and hemosiderin deposits were detected in kidney samples. Contamination of the organs by embolized micro-particles was suspected at the autopsy after discovery of visible damage (scratches) of the pump impeller surface (made from titanium alloy) in both experiments. Sporadic deposits of foreign micro-particles (presumably titanium) were observed in most of the analyzed parenchymal organs. However, the described deposits were not in direct connection with inflammatory reactions in the analyzed tissues. Histopathological analysis showed the presence of minimal contamination of the lung, kidney, and liver tissue samples by foreign material (titanium very likely). The analysis showed only limited pathological changes, especially in liver and kidneys, which might be attributed to the influence of artificial perfusion often observed in chronic TAH experiments.

DOI： 10.1111/aor.12689

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担当区分：筆頭著者   記述言語：日本語   掲載種別：研究論文（その他学術会議資料等）  

記述言語：日本語   出版者・発行元：(一社)日本人工臓器学会  

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：NATURE PUBLISHING GROUP  

In vivo electronic monitoring systems are promising technology to obtain biosignals with high spatiotemporal resolution and sensitivity. Here we demonstrate the fabrication of a biocompatible highly conductive gel composite comprising multi-walled carbon nanotube-dispersed sheet with an aqueous hydrogel. This gel composite exhibits admittance of 100 mS cm(-2) and maintains high admittance even in a low-frequency range. On implantation into a living hypodermal tissue for 4 weeks, it showed a small foreign-body reaction compared with widely used metal electrodes. Capitalizing on the multi-functional gel composite, we fabricated an ultrathin and mechanically flexible organic active matrix amplifier on a 1.2-mu m-thick polyethylene-naphthalate film to amplify (amplification factor: B200) weak biosignals. The composite was integrated to the amplifier to realize a direct lead epicardial electrocardiography that is easily spread over an uneven heart tissue.

DOI： 10.1038/ncomms11425

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：WILEY-BLACKWELL  

Lymph nodes are selectively removed in order to diagnose cancer metastases. In this investigation, we developed a magnetic probe for intraoperatively detecting the accumulation of magnetic fluid. We built a magnetic probe consisting of a permanent magnet and a Hall effect sensor, and investigated its sensitivity. The results agreed well with the numerical results. In addition, a prototype probe detected 1.6 mL of magnetic fluid located 30 mm from the probe head.

DOI： 10.1002/ecj.11757

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記述言語：英語  

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記述言語：日本語  

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：NATL ACAD SCIENCES  

We report a fabrication method for flexible and printable thermal sensors based on composites of semicrystalline acrylate polymers and graphite with a high sensitivity of 20 mK and a high-speed response time of less than 100 ms. These devices exhibit large resistance changes near body temperature under physiological conditions with high repeatability (1,800 times). Device performance is largely unaffected by bending to radii below 700 mu m, which allows for conformal application to the surface of living tissue. The sensing temperature can be tuned between 25 degrees C and 50 degrees C, which covers all relevant physiological temperatures. Furthermore, we demonstrate flexible active-matrix thermal sensors which can resolve spatial temperature gradients over a large area. With this flexible ultrasensitive temperature sensor we succeeded in the in vivo measurement of cyclic temperatures changes of 0.1 degrees C in a rat lung during breathing, without interference from constant tissue motion. This result conclusively shows that the lung of a warm-blooded animal maintains surprising temperature stability despite the large difference between core temperature and inhaled air temperature.

DOI： 10.1073/pnas.1515650112

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記述言語：日本語   出版者・発行元：(一社)日本人工臓器学会  

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記述言語：日本語   出版者・発行元：(一社)ライフサポート学会  

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：SPRINGER JAPAN KK  

The helical flow pump (HFP) was invented to be an ideal pump for developing the TAH and the helical flow TAH (HFTAH) using two HFPs has been developed. However, since the HFP is quite a new pump, hydrodynamic characteristics inside the pump are not clarified. To analyze hydrodynamic characteristics of the HFP, flow visualization study using the particle image velocimetry and computational fluid dynamics analysis were performed. The experimental and computational models were developed to simulate the left HFP of the HFTAH and distributions of flow velocity vectors, shear stress and pressure inside the pump were examined. In distribution of flow velocity vectors, the vortexes in the vane were observed, which indicated that the HFP has a novel and quite unique working principle in which centrifugal force rotates the fluid in the helical volutes and the fluid is transferred from the inlet to the outlet helical volutes according to the helical structure. In distribution of shear stress, the highest shear stress that was considered to be occurred by the shunt flow across the impeller was found around the entrance of the inlet helical volute. However, it was not so high to cause hemolysis. This shunt flow is thought to be improved by redesigning the inlet and outlet helical volutes. In distribution of pressure, negative pressure was found near the entrance of the inlet helical volute. However, it was not high. Negative pressure is thought to be reduced with an improvement in the design of the impeller or the vane shape.

DOI： 10.1007/s10047-015-0828-y

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：WILEY-BLACKWELL  

Severe cardiac failure patients require a total artificial heart (TAH) to save life. To realize a TAH that can fit a body of small stature and has high performance, high durability, good anatomical fitting, good blood compatibility, and physiological control, we have been developing the helical flow TAH (HFTAH) with two helical flow pumps with hydrodynamic levitation impeller. Animal experiments of the HFTAH were conducted to perform in vivo studies. The HFTAH was implanted in 13 adult female goats weighing 45.0-64.0kg. After surgery, neither anti-coagulant nor anti-platelet medication was given systemically. The HFTAH was usually driven with a quasi-pulsatile mode. The 1/R control or P control was applied to control the circulation. The P control is a new method using simplified equation of the 1/R control. The HFTAH could be implanted in all goats with good anatomical fitting. Two goats survived for a long time (100 and 68 days). Major causes of termination were device failure and surgical complications. In the device failure, trouble with hydrodynamic bearing was conspicuous. In the two long-term survived goats, experiments were terminated with bearing instability that was probably caused by the suction effect. In these goats, hemolysis occurred on postoperative day 88 and 44, which was considered to be relevant to the bearing trouble. Thrombus was found at the broken right bearing of the 100-day survived goat. However, antithrombogenicity of the pump is expected to be good unless bearing trouble occurs. In two long-term survived goats, the 1/R control or P control worked appropriately to prevent the elevation of right atrial pressure. In both goats, hemodynamic parameters changed with the condition of the animals, liver and kidney functions remained almost normal except when recovering from surgery and during hemolysis, and total protein recovered 2 weeks after surgery. Although instability of the hydrodynamic bearing should be improved, performance of the HFTAH with physiological control could be demonstrated.

DOI： 10.1111/aor.12543

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記述言語：日本語   出版者・発行元：一般社団法人 日本生体医工学会  

Hybrid material consisting of artificial scaffold and living tissue achieves both of high biocompatibility and mechanical strength. The purpose of this study was to investigate the feasibility of the hybrid material for use as a blood protein filter. Sheet-like hybrid materials were fabricated in animals, and their antithrombogenicity and filter performance were evaluated. The materials were extracted from the body at 100 days after implantation. The tissues were decellularized using sodium dodecyl sulfate for preventing immunological rejection. A short-term test of antithrombogenicity was carried out by dropping blood on the material. The quantity of blood coagulation on the hybrid material was much smaller than those of polysulfone and cellulose. A blood cannula made of the hybrid material was implanted in a goat to evaluate the long-term antithrombogenicity. No clot was observed on the cannula even after 1 month of continuous exposure to blood. Blood plasma was filtered through the hybrid material to evaluate the removal of protein and the lifetime. The hybrid material showed protein removal ratio comparable to the conventional filters. The lifetime of one month was 6 times as long as that of polysulfone

DOI： 10.11239/jsmbe.53.S194_03

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記述言語：英語  

DOI： 10.4172/2379-1764.1000145

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：IEEE  

We developed a magnetic resonance imaging (MRI) -detectable wireless flexible pressure sensor with pressure-sensitive LC resonator fabricated on a flexible film substrate. Measuring pressures in the body such as blood vessels and cardiac ventricle are very important in making diagnoses and in postoperative observation. However, conventional wired pressure sensors have difficulty in maintaining their connections to external readout equipment, and they also increase the risk of infection during and after implantation. In this study, to read the pressure wirelessly using an MRI system, an LC resonator consisting of a spiral coil and a pressure-sensitive capacitor was designed resonate at 300 MHz which corresponds to the Larmor frequency in an external magnetic field of 7-T. In order to validate the operating principle of the fabricated device, the frequency-impedance characteristics were measured by changing the pressure. The resonance frequencies of complemented LC circuits were lower by approximately 10% than those of nonpressured conditions. After implanting these devices in a 1% agarose gel, MR images were acquired by inducing pressures close to blood pressures of 20 kPa. As a result, contrast changes in the MR images were observed around the integrated spiral coils. This result indicated that the developed flexible pressure sensor has sufficient sensitivity to measure physiological pressure such as blood pressure of 20 kPa wirelessly in the body. In the future, quantitative pressure sensing will be evaluated by comparing it to the contrast changes in MR images with flip angle mapping.

DOI： 10.1109/EMBC.2015.7319066

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記述言語：日本語   出版者・発行元：一般社団法人 日本生体医工学会  

During a cardiac surgery for cardiomyopathy or infarction, the position of lesion has been identified by palpation, myocardiogram examination or thermometry scan. However, technical limitations such as relatively long examination time and less spatial resolution have remained. In this study, to detect the accurate position of lesion quickly even on a surface of beating heart, we developed an ultra-flexible electrode array for myocardiogram measurement. A gold patterned electrode array of 50-nm-thickness was fabricated on a 1.4-&mu;m-thick PEN film and insulated with an additional Parylene-C layer of 1.5-&mu;m-thickness. The living heart surface of a Wistar rat (male, 300g) was exposed under isoflurane anesthesia. Attaching the flexible electrodes to that, the distribution of myocardiogram was measured. The measured result successfully described the distribution of cardiac action potential at the heart surface. The ultra-flexibility of electrode device prevents damage of the heart and surrounding organs like lung. In the future, an implantable flexible electrode device equipped with sensors and amplifier with flexible transistors will be developed for clinical applications.

DOI： 10.11239/jsmbe.53.S269_02

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記述言語：日本語   出版者・発行元：一般社団法人 日本生体医工学会  

Effects of long-term continuous electric stimulation on angiogenesis have been investigated for potential therapeutic applications. Evaluation of the effect has been carried out mainly through observation of extracted tissues after the long-term stimulation. The purpose of this study is to observe angiogenesis in vivo under application of electric stimulations. We developed an implantable device equipped with a scaffold, CMOS-camera and electrodes for real-time observation. The scaffolds and electrodes were placed in 2 experimental chambers. The device has 1.3 mega pixel CMOS sensor, auto-focus lenses and white LED as light source. The electrode was consisted of 1.4&micro;m PET film as substrate and 50nm gold as conductor. The device was implanted under the skin of a goat, and get picture and applied the electric stimulations for 60 days. The electric stimulations were applied with a 60 kHz sinusoidal waveform and a current density of 300 uA/mm2. Angiogenesis occurred in 0.1 mm/day in the non-stimulated device, while no angiogenesis was observed in the device without stimulation. These results show that electric stimulations of this condition are effective for suppressing angiogenesis.

DOI： 10.11239/jsmbe.53.S229_02

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：NATURE PUBLISHING GROUP  

To measure electrophysiological signals from the human body, it is essential to establish stable, gentle and nonallergic contacts between the targeted biological tissue and the electrical probes. However, it is difficult to form a stable interface between the two for long periods, especially when the surface of the biological tissue is wet and/or the tissue exhibits motion. Here we resolve this difficulty by designing and fabricating smart, stress-absorbing electronic devices that can adhere to wet and complex tissue surfaces and allow for reliable, long-term measurements of vital signals. We demonstrate a multielectrode array, which can be attached to the surface of a rat heart, resulting in good conformal contact for more than 3 h. Furthermore, we demonstrate arrays of highly sensitive, stretchable strain sensors using a similar design. Ultra-flexible electronics with enhanced adhesion to tissue could enable future applications in chronic in vivo monitoring of biological signals.

DOI： 10.1038/ncomms6898

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC  

A 64-channel surface electromyogram (EMG) measurement sheet (SEMS) with 2 V organic transistors on a 1 mu m-thick ultra-flexible polyethylene naphthalate (PEN) film is developed for prosthetic hand control. The surface EMG electrodes must satisfy the following three requirements; high mechanical flexibility, high electrode density and high signal integrity. To achieve high electrode density and high signal integrity, a distributed and shared amplifier (DSA) architecture is proposed, which enables an in-situ amplification of the myoelectric signal with a fourfold increase in EMG electrode density. In addition, a post-fabrication select-and-connect (SAC) method is proposed to cope with the large mismatch of organic transistors. The proposed SAC method reduces the area and the power overhead by 96% and 98.2%, respectively, compared with the use of conventional parallel transistors to reduce the transistor mismatch by a factor of 10.

DOI： 10.1109/TBCAS.2014.2314135

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：SPRINGER JAPAN KK  

The total artificial heart (TAH) requires physiological control to respond to the metabolic demand of the body. To date, 1/R control is a single physiological control method that can control venous pressure. To realize an implantable 1/R control system, we are developing a new pressure measuring method using absolute pressure sensor. To find a method for absolute pressure sensor, which went well without calibration, concept of left atrial pressure (LAP) estimation using its pulsatile amplitude was proposed. Its possibility was investigated with two long-term survived goats whose hearts were replaced with the helical flow TAHs. In manual control condition, there existed a positive relation between mean LAP (mLAP) and normalized pulsatile amplitude (NPA). Percent systole revealed not to affect the relationship between mLAP and NPA. Dispersion was observed between different pulse rates. As for cardiac output difference (QLD) that is the difference of flow rate between systolic and diastolic phases, similar results were obtained except in low QLDs. In the 1/R control condition, relatively high correlation between mLAP and NPA could be obtained. In estimation of mLAP using the correlating function of individual goat, fairly good correlation was obtained between measured mLAP and estimated mLAP. Despite that further studies are necessary, it was demonstrated that the concept of the LAP estimation could be possible.

DOI： 10.1007/s10047-014-0788-7

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記述言語：日本語   出版者・発行元：(一社)日本人工臓器学会  

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記述言語：日本語   出版者・発行元：(一社)日本人工臓器学会  

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記述言語：日本語   出版者・発行元：(一社)日本人工臓器学会  

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Japan Soc. of Med. Electronics and Biol. Engineering  

Assistive communication devices are available for deaf or hard-of-hearing (DHH) individuals. However, these devices often are only for face-to-face use and cannot provide text or symbol equivalents of verbal communication such as warnings, orders or requests. This paper suggests a new solution by a remote communication system based on an Android Smartphone for text communication from a family member or a health care worker to a DHH individual. This system was found to be good for home use from the viewpoints of coverage, cost, and simplicity.

DOI： 10.11239/jsmbe.52.O-446

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Japan Soc. of Med. Electronics and Biol. Engineering  

The purpose of this research is to establish sterilization method and preservation method for long time of hybrid material. Hybrid material was freeze dried and hybrid material was sterilized by four methods.The sterilization methods are autoclave, dry heat, ethylene oxide gas(EOG), and hydrogen peroxide gas plasma.We evaluate sterilization to compare structural change before and after the sterilization by microscopic observation.In autoclave and dry heat, hybrid materials were change color and transformation by heat.In these results, EOG sterilization is most suitable method of the hybrid material.Next, It is planed evaluate this sterilization method by cell culturing and animal experiment.

DOI： 10.11239/jsmbe.52.O-555

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Japan Soc. of Med. Electronics and Biol. Engineering  

The purpose of this study is to investigate the effect of electrical stimulation on angiogenesis. We developed an implantable camera device which observes blood vessels in animal bodies with stimulating electrodes. This device was implanted under the goat skin for 60 days. Electrical stimulations were applied with a sinusoidal wave of 60 kHz and a current density of 300 uA/mm2. Angiogenesis was clearly observed in the non-stimulated chamber, while angiogenesis did not occur in the stimulated chamber. These results show that electrical stimulation of this condition has effective to suppress angiogenesis.

DOI： 10.11239/jsmbe.52.O-249

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Japan Soc. of Med. Electronics and Biol. Engineering  

The helical flow pump (HFP) for the total artificial heart (TAH) has been developed. In the recent hemolysis test, normalized index of hemolysis (NIH) of HFP is 0.71 times of BioPump (BPX-80). Comparing to blood pumps in clinical field, further improvement is still significant task. Computational fluid dynamics analysis is carried out to determine risky area of the hemolysis in the flow passage except hydrodynamic bearing. And shear stress and duration along the stream lines which is regarded as a path of Red blood cells are analyzed. As the result, 0 deg and 180 deg of rotational angle where confluent or split-flow with large flow speed difference are clarified as risky area of hemolysis.

DOI： 10.11239/jsmbe.52.O-535

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：WILEY-V C H VERLAG GMBH  

A unique form of adaptive electronics is demonstrated, which change their mechanical properties from rigid and planar to soft and compliant, in order to enable soft and conformal wrapping around 3D objects, including biological tissue. These devices feature excellent mechanical robustness and maintain initial electrical properties even after changing shape and stiffness.

DOI： 10.1002/adma.201400420

Web of Science

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   出版者・発行元：Japanese Society for Medical and Biological Engineering  

DOI： 10.11239/jsmbe.51.R-229

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掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：IEEE  

DOI： 10.1109/EMBC.2013.6610102

Web of Science

PubMed

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：IEEE  

The undulation pump ventricular assist device (UPVAD) is a small implantable ventricular assist device using an undulation pump. The UPVAD can produce pulsatile flow by changing the motor rotation speed of the UPVAD. Because the undulation pump is a volume displacement type pump, the inflow sucking occurs easily. The purpose of this study is to develop a suitable control method for the UPVAD. The UPVAD inflow cannula equipped with an implantable pressure sensor was inserted into the ventricle. Therefore, pressure variation that synchronized with the natural heartbeat and negative pressure spike caused the inflow sucking were observed. By changing the motor rotation speed that responded to the inflow pressure, the UPVAD could synchronize with the natural heartbeat and the UPVAD could generate a co-pulse assist flow. The inflow sucking could be released by reducing the motor rotation speed, if the inflow sucking was detected. The newly developed control method exhibited superior characteristics than existing ones due to high immunity against pressure sensor drift. The assist flow could be increased more than 15% and the inflow sucking occurrence could be decreased with this control method. The UPVAD could generate the suitable assist flow with the developed control method.

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

担当区分：筆頭著者   記述言語：日本語   掲載種別：研究論文（学術雑誌）  

担当区分：筆頭著者   記述言語：日本語   掲載種別：研究論文（その他学術会議資料等）  

記述言語：日本語   出版者・発行元：(一社)日本人工臓器学会  

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記述言語：日本語   出版者・発行元：(一社)日本人工臓器学会  

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記述言語：日本語   出版者・発行元：[科学情報出版]  

CiNii Books

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記述言語：日本語   出版者・発行元：名古屋 : エリザベス・アーノルド富士財団  

CiNii Books

CiNii Research

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その他リンク： https://ndlsearch.ndl.go.jp/books/R000000004-I029340803

記述言語：日本語   出版者・発行元：日本循環制御医学会  

DOI： 10.11312/ccm.37.185

J-GLOBAL

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記述言語：日本語   出版者・発行元：(一社)日本人工臓器学会  

J-GLOBAL

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記述言語：日本語   出版者・発行元：(一社)ライフサポート学会  

J-GLOBAL

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記述言語：日本語   出版者・発行元：北海道外科学会  

J-GLOBAL

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記述言語：英語  

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記述言語：日本語   出版者・発行元：(一社)日本人工臓器学会  

J-GLOBAL

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記述言語：日本語   出版者・発行元：(一社)日本人工臓器学会  

J-GLOBAL

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記述言語：英語   出版者・発行元：(一社)日本人工臓器学会  

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記述言語：日本語   出版者・発行元：北海道外科学会  

J-GLOBAL

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記述言語：英語  

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記述言語：日本語   掲載種別：機関テクニカルレポート，技術報告書，プレプリント等   出版者・発行元：飯島藤十郎記念食品科学振興財団  

CiNii Books

J-GLOBAL

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記述言語：英語  

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記述言語：日本語   出版者・発行元：(一社)日本人工臓器学会  

J-GLOBAL

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記述言語：日本語   出版者・発行元：(一社)日本人工臓器学会  

J-GLOBAL

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記述言語：日本語   出版者・発行元：(一社)日本人工臓器学会  

J-GLOBAL

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記述言語：日本語   出版者・発行元：(一社)日本人工臓器学会  

J-GLOBAL

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記述言語：日本語   出版者・発行元：(一社)日本人工臓器学会  

J-GLOBAL

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記述言語：日本語  

J-GLOBAL

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記述言語：日本語   出版者・発行元：Japan Soc. of Med. Electronics and Biol. Engineering  

The design requirements of the blood pump for implantable ventricular devices and total artificial heart are heavily affected by the anatomical limitation such as the intrathoracic space capacity and blood vessel layout. It is also necessary to modify the design of blood pumps for built-in use in the case of integrated pump lung system. Limitation occurs at the blood inflow position to the oxygenator whether the configuration of oxygenator was cylindrical or box shape. The design and structure of outflow port in the blood pump was decided according to the smoothness of the blood flow. Our research group tried to design the blood pumps specialized for built-in apparatus. In this study, we report a newly designed the multi-stage centrifugal pump named Sequential Flow Pump that two steps of pressurization is possible with one impeller.

DOI： 10.11239/jsmbe.52.OS-24

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記述言語：日本語   出版者・発行元：北海道外科学会  

J-GLOBAL

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記述言語：日本語   出版者・発行元：公益社団法人 日本生体医工学会  

The problem is wedge thrombus due to material of cannula. We thought that to solve the problem replace its' material with hybrid material. Hybrid blood inflow cannula is formed by implanting the core which consist of polyester velour and titanium conduit. Then, the cell component decellularized. By using this cannula, examined on chronic animal experiment with VAD in heterologous transplantation to evaluate the biocompatibility of cannula. As a result, the goat survived 53days without antithrombogenic agents and the cannula was connected to neighboring cardiac muscle smoothly and thrombos weren't formed. And the result of immunostaining, surface of cannula was coated with endothelial cells.

DOI： 10.11239/jsmbe.52.O-243

J-GLOBAL

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J-GLOBAL

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記述言語：英語   出版者・発行元：(一社)日本人工臓器学会  

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記述言語：英語   出版者・発行元：(一社)日本人工臓器学会  

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記述言語：英語   出版者・発行元：(一社)日本人工臓器学会  

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記述言語：日本語   出版者・発行元：(一社)日本人工臓器学会  

J-GLOBAL

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開催年月日： 2023年8月 - 2023年9月

記述言語：英語   会議種別：口頭発表（一般）  

開催年月日： 2023年2月

記述言語：日本語   会議種別：口頭発表（一般）  

開催年月日： 2022年11月

記述言語：日本語   会議種別：ポスター発表  

開催年月日： 2022年11月

記述言語：英語   会議種別：口頭発表（一般）  

開催年月日： 2022年2月

記述言語：日本語   会議種別：口頭発表（一般）  

開催年月日： 2022年2月

記述言語：英語   会議種別：口頭発表（一般）  

開催年月日： 2022年1月

記述言語：日本語   会議種別：口頭発表（一般）  

開催年月日： 2021年11月

記述言語：日本語   会議種別：口頭発表（一般）  

開催年月日： 2021年11月

記述言語：日本語   会議種別：口頭発表（一般）  

開催地：千葉県  

開催年月日： 2021年11月

記述言語：日本語   会議種別：口頭発表（一般）  

開催地：千葉県  

開催年月日： 2021年11月

記述言語：日本語   会議種別：口頭発表（一般）  

開催地：千葉県  

開催年月日： 2021年10月 - 2021年11月

記述言語：日本語   会議種別：口頭発表（一般）  

開催年月日： 2021年7月

記述言語：英語   会議種別：口頭発表（一般）  

開催年月日： 2021年6月

記述言語：日本語   会議種別：口頭発表（一般）  

開催年月日： 2021年2月

記述言語：日本語   会議種別：シンポジウム・ワークショップ パネル（公募）  

開催年月日： 2021年2月

記述言語：日本語   会議種別：口頭発表（一般）  

開催年月日： 2021年1月

記述言語：英語   会議種別：口頭発表（一般）  

開催年月日： 2020年11月

記述言語：日本語   会議種別：口頭発表（一般）  

開催年月日： 2020年11月

記述言語：日本語   会議種別：口頭発表（一般）  

開催年月日： 2020年11月

記述言語：日本語   会議種別：シンポジウム・ワークショップ パネル（指名）  

開催年月日： 2020年11月

記述言語：英語   会議種別：口頭発表（一般）  

開催年月日： 2020年11月

記述言語：日本語   会議種別：口頭発表（一般）  

開催年月日： 2020年11月

記述言語：日本語   会議種別：口頭発表（一般）  

開催年月日： 2020年11月

記述言語：日本語   会議種別：口頭発表（一般）  

開催年月日： 2020年11月

記述言語：日本語   会議種別：口頭発表（一般）  

開催年月日： 2020年11月

記述言語：日本語   会議種別：口頭発表（一般）  

開催年月日： 2020年9月

記述言語：日本語   会議種別：口頭発表（一般）  

開催年月日： 2020年7月

記述言語：英語   会議種別：口頭発表（一般）  

開催年月日： 2020年7月

記述言語：日本語   会議種別：口頭発表（一般）  

開催年月日： 2020年5月

記述言語：日本語   会議種別：口頭発表（一般）  

開催年月日： 2020年5月

記述言語：日本語   会議種別：シンポジウム・ワークショップ パネル（指名）  

開催年月日： 2020年5月

記述言語：日本語   会議種別：ポスター発表  

出願人：国立大学法人旭川医科大学、バイオチューブ株式会社

出願番号：特願2022-040595  出願日：2022年3月

出願国：国内  

出願人：国立大学法人東京工業大学,国立大学法人東京医科歯科大学,国立大学法人旭川医科大学

出願番号：特願2021-167592   出願日：2021年10月

出願国：国内  

出願番号：2021-111590  出願日：2021年7月

出願国：国内  

出願番号：2020-145958  出願日：2020年6月

出願国：国内  

受賞区分：国内学会・会議・シンポジウム等の賞 

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受賞区分：国内学会・会議・シンポジウム等の賞 

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受賞区分：国内学会・会議・シンポジウム等の賞 

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受賞区分：国内学会・会議・シンポジウム等の賞 

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受賞区分：国内外の国際的学術賞 

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受賞区分：国内学会・会議・シンポジウム等の賞 

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2022年2月19日に旭川医科大学先進医工学研究センター主催医療の最先端講座を開催し、小中学生を対象とした公開講座をオンラインで開催し、運営した。

Frontiers in Nanotechnology, 2020年のIF=5.750

日本生体医工学会の英文学会誌査読委員

賞選活動

JSAO（日本人工臓器学会）査読委員

学会運営・方針決定（3,900名）

選奨委員

IFAO（国際人工臓器学会）論文誌査読

年次大会の方針決定・調整

学会運営（2,700名）