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Mathematical modeling and experimental analysis of the relationship between ventricular size and diastolic function of trabecular ventricles

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Journal of Biorheology 2023年第2期37卷 96-104页

作者： Ito, Megumi Ujihara, Yoshihiro Sugita, Shukei Nakamura, Masanori Nanopharmaceutical Sciences Graduate School of Engineering Nagoya Institute of Technology Gokiso-cho Showa-ku Aichi Nagoya4668555 Japan Department of Electrical and Mechanical Engineering Graduate School of Engineering Nagoya Institute of Technology Gokiso-cho Showa-ku Aichi Nagoya4668555 Japan Center of Biomedical Physics and Information Technology Nagoya Institute of Technology Gokiso-cho Showa-ku Aichi Nagoya4668555 Japan Department of Nanopharmaceutical Sciences Nagoya Institute of Technology Gokiso-cho Showa-ku Aichi Nagoya4668555 Japan

The diastolic function of the ventricle is evaluated using the ventricular diastolic pressure-volume (P-V) relationship, and the P-V relationship is generally quantified by the stiffness or the stiffness constant. The P-V relationship of humans and other mammals is often normalized with the ventricular lumen volume to exclude the size effect on ventricular stiffness;however, in amphibians and reptiles which have trabecular ventricles, the ventricular mass is used for normalization instead of the ventricular lumen volume, because it is difficult to accurately define the ventricular lumen. In the present study, we investigated the ventricular diastolic P-V relationships of anurans of different sizes, and demonstrated both mathematically and experimentally that the stiffness parameters obtained directly from the P-V relationship were inversely proportional to the ventricular mass. We also demonstrated that the volume of the natural ventricular lumen was proportional to the ventricular mass. These combined results indicate that the stiffness parameters obtained directly from the P-V relationship are essentially dependent on the ventricular size. Normalization of V with ventricular mass attenuated the size effect, and we confirmed that this method is useful for comparing the diastolic function between the trabecular ventricles of different sizes when focusing on material properties. © 2023, Japanese Society of Biorheology. All rights reserved.

关键词： Stiffness

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Hands-free interface for surgical procedures based on foot movement patterns

Hands-free interface for surgical procedures based on foot m...

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Annual International Conference of the IEEE engineering in Medicine and Biology Society (EMBC)

作者： Toshikazu Kawai Masanori Fukunishi Atsushi Nishikawa Yuji Nishizawa Tatsuo Nakamura Major in Biomedical Engineering Osaka Institute of Technology Osaka JAPAN Department of Textile Science and Technology Shinshu University Ueda JAPAN Department of Gastroenterological Surgery Kagawa University Kita-gun JAPAN Department of Colonic Surgery National Cancer Center Hospital East Kashiwa JAPAN Frontier Medical Sciences Kyoto University Kyoto JAPAN

A hands-free interface has been developed to allow a single surgeon to control a locally operated forceps manipulating robot. It is based on the use of a pressure sensor sheet placed on the floor to measure temporal changes in the center of gravity of the operator's foot, in addition to the applied force. Pattern recognition was carried out during trials with endoscope specialists and students for six different types of foot movements. The specialist patterns were then used to develop an interface for controlling a robot with five degrees of freedom. Using this control interface, it was found that the robot could successfully handle a model organ during simulated surgery.

关键词： Foot Surgery Gravity Manipulators Robot sensing systems

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In situ measurements of attenuation coefficient for evaluating the hardness of cataract lens by a high frequency ultrasonic needle transducer

In situ measurements of attenuation coefficient for evaluati...

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IEEE International Ultrasonics Symposium

作者： Chih-Chung Huang Ruimin Chen Po-Hsiang Tsui Qifa Zhou Mark S. Humayun K. Kirk Shung Department of Electronic Engineering Fu Jen Catholic University NIH Resource on Medical Ultrasonic Transducer Technology Department of Biomedical Engineering University of Southern California Division of Mechanics Research Center for Applied Sciences Academia Sinica Doheny Retina Institute Doheny Eye Institute Department of Ophthalmology Keck School of Medicine University of Southern California

ISBN: (纸本)9781424443895;9781424443901

A cataract is a clouding of the lens in the eye that affects vision. Phacoemulsification is the mostly common surgical method for treating cataracts, and determining the optimal phacoemulsification energy is dependent on measuring the hardness of the lens. This study explored the use of an ultrasound needle transducer for in situ minimally invasive measurements of ultrasound attenuation coefficient to evaluate the hardness of cataract lens. A 47 MHz high frequency needle transducer with a diameter of 0.9 mm was fabricated by a polarized PMN-33%PT single crystal in the present study. The attenuation coefficients at different stages of artificial porcine cataract lens were measured using the spectral shift approach. The hardness of the cataract lens was also evaluated by mechanical measurement of its elastic properties. The results demonstrated that the ultrasonic attenuation coefficient was increased from 0.048±0.02 to 0.520±0.06 dB/mm-MHz corresponding to an increase of Young's modulus from 6 to 96 kPa as the cataract further developed. In order to evaluate the feasibility of combining needle transducer and phacoemulsification probe for real time measurement during cataract surgery, the needle transducer was mounted on the phacoemulsification probe for vibration test. The results indicated that there was no apparent damage to the tip of needle transducer and the pulse-echo test showed a good performance in sensitivity was maintained after the vibration test.

关键词： attenuation coefficients Cataract Lenses Transducers lens vibration monitoring NEEDLES Soundness Lens Plant hardness site measurements Phacoemulsification Mechanical measurements

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Extracellular vesicles as a promising platform of precision medicine in liver cancer

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Pharmacological research 2025年 107800页

作者： Keyang Xu Qibiao Wu Zhao Lingyun Romario Nguyen Fatema Safri William Yang Yikun Xu Yun Ye Hiu Yee Kwan Qiang Wang Xiuming Liang Muhammad J A Shiddiky Majid E Warkiani Jacob George Jianfeng Bao Liang Qiao Faculty of Chinese Medicine and State Key Laboratory of Quality Research in Chinese Medicine Macau University of Science and Technology Macau 999078 China. Storr Liver Centre Westmead Institute for Medical Research the University of Sydney and Westmead Hospital Westmead NSW 2145 Australia. Centre for Cancer & Inflammation Research School of Chinese Medicine Hong Kong Baptist University 999077 Hong Kong China. Division of Medical Imaging and Technology Department of Clinical Science Intervention and Technology (CLINTEC) Karolinska Institute Stockholm Sweden. Biomolecular Medicine Clinical Research Center Department of Laboratory Medicine Karolinska Institute Stockholm Sweden. Rural Health Research Institute (RHRI) Charles Sturt University Orange NSW 2800 Australia. School of Biomedical Engineering the University of Technology Sydney Ultimo NSW 2007 Australia. Hangzhou Xixi Hospital affiliated to Zhejiang Chinese Medical University Zhejiang China. Electronic address: zjbjf1972@***. Storr Liver Centre Westmead Institute for Medical Research the University of Sydney and Westmead Hospital Westmead NSW 2145 Australia. Electronic address: liang.qiao@sydney.edu.au.

Extracellular vesicles (EVs) are natural carriers of biological information and play pivotal roles in intercellular communication. EVs are biocompatible, have low immunogenicity, and are capable of traversing biological barriers, making them ideal tools for disease diagnosis and therapy. Despite their promising prospects, the full realization of EVs potential faces several challenges. This article aims to comprehensively review the biological and molecular features of EVs, their applications in liver cancer and possible underlying mechanisms, and the critical challenges affecting the clinical translation of EVs-based therapies in liver cancer.

关键词： Extracellular vesicles (EVs) liver cancer organoids standardization therapeutic tools

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A low-molecular-weight chitosan fluorometric-based assay for evaluating antiangiogenic drugs

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International Journal of Biological Macromolecules 2023年 224卷 927-937页

作者： Wang, Cheng-Yu Chou, Chih-Ming Chu, Cheng-Ying Chen, Amy Liu, En-Hsin Liu, Cheng-Yang Lee, Yu-Lin Amy Mi, Fwu-Long Cheng, Chia-Hsiung Department of Radiation Oncology Yuan's General Hospital Kaohsiung80249 Taiwan Department of Biochemistry and Molecular Cell Biology School of Medicine College of Medicine Taipei Medical University Taipei11031 Taiwan TMU Research Center of Cancer Translational Medicine Taipei Medical University Taipei110 Taiwan CRISPR Gene Targeting Core Lab Taipei Medical University Taipei110 Taiwan School of Medical Laboratory Science and Biotechnology College of Medical Science and Technology Taipei Medical University Taipei110 Taiwan Department of Biomedical Engineering National Yang Ming Chiao Tung University Taipei112 Taiwan Department of Medicine Duke University School of Medicine DurhamNC27710 United States

Low-molecular-weight chitosan (LMWCS) damaged cell membranes in zebrafish showed its possibility to release reporter proteins for detection. In this study, we developed a simple fluorometric-based assay for the evaluation of clinical antiangiogenic drugs using LMWCS and Tg(fli1:EGFP) transgenic zebrafish, which expressed green-fluorescence protein (GFP) in the endothelial cells of blood vessel. In vitro stable and transiently transfected cell lines was released luciferase and green fluorescent protein (GFP) for intensity evaluation upon LMWCS fluorometric-based assay. In vivo Tg(fli1:EGFP) transgenic zebrafish was also released GFP from endothelial cells of blood vessels and show an increase of fluorescent intensity upon LMWCS fluorometric-based assay. Treatment with the clinical antiangiogenic drug sorafenib and analyzed by LMWCS fluorometric-based assay showed significantly reduction of angiogenesis. Furthermore, treatment with 2 μM sorafenib showed a significant reduction in angiogenesis of the intersegmental vein (ISV) and dorsal longitudinal anastomotic vessels (DLAV) in Tg(fli1:EGFP) transgenic zebrafish. Fluorescence intensity reduction from 2 μM sorafenib was used as a factor in the LMWCS fluorescence-based assay for relative antiangiogenic evaluation. Relative angiogenesis evaluation of the clinical drugs axitinib, cabozantinib, and regorafenib showed a significant reduction. Collectively, this study provided a simple, convenient, and rapid LMWCS fluorometric-based assay for evaluating angiogenic drugs using transgenic zebrafish. © 2022

关键词： Blood vessels

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High-throughput and label-free detection of immunoglobulin G interactions based on reflectometric interference imaging system

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Guangxue Xuebao/Acta Optica Sinica 2010年第SUPPL.期30卷

作者： Li, Qiang Gan, Wupeng Huang, Guoliang Chen, Shengyi Li, Xin Department of Biomedical Engineering School of Medicine Tsinghua University Beijing 100084 China National Engineering Research Center for Beijing Biochip Technology Beijing 102206 China

Recently, reflectometry interference technology has been widely used in detections of biomolecular interaction, food security and drug screening due to its advantages in label-free and dynamic detection. Protein microarray, providing an opportunity to monitor multiple biomolecular interactions simultaneously, has a potential to be used in clinical diagnosis. In this study, we have designed and constructed a label-free, real-time reflectometry interference imaging system that detects interactions of proteins according to optical phase differences from the accumulation of biological material on solid substrates, which can perform the measurement of the change of thickness in nm level. The specific binding between human IgG and anti-human IgG is performed and continuously detected by using this label-free and real-time interference imaging platform. The thickness of SiO2 is optimized so that the interference image with high signal contrast is achieved. In addition, streptavidin coupled microsphere solution is introduced to to enlarge detection signal of the biotin-linked antibody. The experimental results show that the microsphere efficiently increases the intensity of binding sites and improves the sensitivity of detection.

关键词： Microspheres

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Combining time-dependent force perturbations in robot-assisted surgery training

arXiv

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arXiv 2021年

作者： Sharon, Yarden Naftalovich, Daniel Bahar, Lidor Refaely, Yael Nisky, Ilana The Department of Biomedical Engineering Zlotowski Center for Neuroscience Ben-Gurion University of the Negev Israel The Department of Computational & Mathematical Sciences CA United States Institute of Technology United States Keck School of Medicine of USC University of Southern California United States The Thoracic Surgery Unit Soroka Medical Center Israel

Teleoperated robot-assisted minimally-invasive surgery (RAMIS) offers many advantages over open surgery. However, there are still no guidelines for training skills in RAMIS. Motor learning theories have the potential to improve the design of RAMIS training but they are based on simple movements that do not resemble the complex movements required in surgery. To fill this gap, we designed an experiment to investigate the effect of time-dependent force perturbations on the learning of a pattern-cutting surgical task. Thirty participants took part in the experiment: (1) a control group that trained without perturbations, and (2) a 1Hz group that trained with 1Hz periodic force perturbations that pushed each participant's hand inwards and outwards in the radial direction. We monitored their learning using four objective metrics and found that participants in the 1Hz group learned how to overcome the perturbations and improved their performances during training without impairing their performances after the perturbations were removed. Our results present an important step toward understanding the effect of adding perturbations to RAMIS training protocols and improving RAMIS training for the benefit of surgeons and patients. Copyright © 2021, The Authors. All rights reserved.

关键词： Surgical equipment

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A Count-Rate Recovery Method for Photon Counting X-ray Detectors Using Scintillator/SiPM

A Count-Rate Recovery Method for Photon Counting X-ray Detec...

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IEEE Symposium on Nuclear Science (NSS/MIC)

作者： Y. Li X. Wang W. Liu R. Chen D. Zhang X. Zhang N. Jiang N. D’ Ascenzo B. Li D. Xi Q. Xie Department of Electronic Engineering and Information Science University of Science and Technology of China Hefei China Beijing Hangxing Machine Manufacturing Co. Ltd Beijing China Institute of Artificial Intelligence Hefei Comprehensive National Science Center Hefei China Suzhou Raymeasure Technology Co. Ltd Suzhou China Department of Biomedical Engineering Huazhong University of Science and Technology Wuhan China

ISBN: (数字)9798350388152

ISBN: (纸本)9798350388169

Previously, we developed a photon counting detector for X-ray fluoroscopic imaging using a scintillation detector unit and an MVT digitizer. Due to the dead time in the detection channels, the counts will be lost when working in a high count-rate condition. To avoid the streak artifacts in the image, we normally adopt a low X-ray dose when imaging with the detector. However, a low X-ray dose always means a worse imaging signal-to-noise ratio (SNR) or longer imaging time. In this work, we model the response of the detector as a paralyzable processing and set up an X-ray imaging system with the detectors for validation. By analyzing the measured count rate of the detector when setting the X-ray tube’s voltage at 120 kV and varying the current from 0.1 mA to 1.2 mA, we estimated the dead time of each channel in the detector to be (112±11) ns. Having the dead time and the paralyzable response model, the lost counts therefore could be recovered according to the measured value. Typically, we measure the count rate of channel 81 to be 2.97 Mcps/pixel and recover it to be 6.20 Mcps/pixel when setting the X-ray tube’s voltage and current at 120 kV and 0.8 mA respectively. An image of the step phantom is further obtained and the streak artifacts in the image are gone after the count-rate recovery and uniformity calibration.

关键词： Semiconductor device measurement Voltage measurement X-ray detectors Semiconductor detectors Current measurement Detectors Time measurement

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Greedy information acquisition algorithm: a new information theoretic method for network growing

Greedy information acquisition algorithm: a new information ...

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International Joint Conference on Neural Networks (IJCNN)

作者： R. Kamimura T. Kamimura O. Uchida T. Takeuchi Information Science Laboratory and Future Science and Technology Joint Research Center Tokai University Hiratsuka Kanagawa Japan Department of English Senshu University Kawasaki Kanagawa Japan Department of Network Engineering Kanagawa Institute of Technology Atsugi Kanagawa Japan Human-Computer Interaction Group Institute for Human Science and Biomedical Engineering National Institute for Advanced Industrial Science and Technology Tsukuba Japan

In this paper, we propose a new information theoretic network growing algorithm. The new approach is called greedy information acquisition, because networks try to absorb as much information as possible in every stage of learning. In the first stage, two competitive units compete with each other by maximizing mutual information. In the successive stages, new competitive units are gradually added and information is maximized. Through greedy information maximization, different sets of important features in input patterns can be cumulatively discovered in successive stages. We applied our approach to a language classification problem. Experimental results confirmed that different features in input patterns are gradually discovered.

关键词： biomedical engineering Information science Humans Mutual information Neural networks Neurons

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Dissociation of Down syndrome and Alzheimer's disease effects with imaging

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Alzheimer's and Dementia: Translational Research and Clinical Interventions 2016年第2期2卷 69-81页

作者： Matthews, Dawn C. Lukic, Ana S. Andrews, Randolph D. Marendic, Boris Brewer, James Rissman, Robert A. Mosconi, Lisa Strother, Stephen C. Wernick, Miles N. Mobley, William C. Ness, Seth Schmidt, Mark E. Rafii, Michael S. ADM Diagnostics Northbrook IL United States Alzheimer's Disease Cooperative Study Department of Neurosciences University of California San Diego School of Medicine San Diego CA United States Department of Psychiatry New York University Langone School of Medicine New York NY United States Rotman Research Institute Baycrest Hospital and Medical Biophysics University of Toronto Toronto ON Canada Departments of Electrical and Computer Engineering and Biomedical Engineering Medical Imaging Research Center Illinois Institute of Technology Chicago IL United States Janssen Research and Development LLC Raritan NJ United States Janssen Pharmaceutica Beerse Belgium

Introduction Down Syndrome (DS) adults experience accumulation of Alzheimer's disease (AD)-like amyloid plaques and tangles and a high incidence of dementia and could provide an enriched population to study AD-targeted treatments. However, to evaluate effects of therapeutic intervention, it is necessary to dissociate the contributions of DS and AD from overall phenotype. Imaging biomarkers offer the potential to characterize and stratify patients who will worsen clinically but have yielded mixed findings in DS subjects. Methods We evaluated 18F fluorodeoxyglucose positron emission tomography (PET), florbetapir PET, and structural magnetic resonance (sMR) image data from 12 nondemented DS adults using advanced multivariate machine learning methods. Results Our results showed distinctive patterns of glucose metabolism and brain volume enabling dissociation of DS and AD effects. AD-like pattern expression corresponded to amyloid burden and clinical measures. Discussion These findings lay groundwork to enable AD clinical trials with characterization and disease-specific tracking of DS adults. © 2016 ADM Diagnostics.

关键词： Alzheimer's Amyloid AV-45 Biomarker initiative Classifier Clinical trials Down syndrome DSBI FDG Glucose metabolism Imaging MRI NPAIRS PET Prodromal

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