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In vivo whole-body imaging of optical agent dynamics using full angle fluorescence diffuse optical tomography

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Chinese Optics Letters 2010年第12期8卷 1156-1159页

作者：刘欣刘飞汪待发白净 Department of biomedical engineering School of MedicineTsinghua University

Dynamic fluorescence diffuse optical tomography （FDOT） is important in drug deliver research. In this letter, we first image the metabolic processes of micelles indocyanine green throughout the whole body of a nude mouse using the full-angle FDOT system with line illumination （L-FDOT）. The resolution of L-FDOT is evaluated using phantom experiment. Next, in vivo dynamic tomographic images （100 frames; approximately 170 min） of mouse liver and abdomen are shown and cross-validated by planar fluorescence reflectance imaging in vitro. Results provide evidence on applicability of the tomographic image wholebody biological activities in vivo on minute timescale （approximately 1.7 min） using L-FDOT.

关键词： Optical tomography

Optimization of specific cell-peptide interactions at the bio-material interface via regulation of nonspecific biofouling interactions

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Science China Chemistry 2020年第2期63卷 143-144页

作者： John L.Brash Department of Chemical engineering School of Biomedical EngineeringMcMaster University

Materials that interact with biological systems in a wellcontrolled,predictable manner are highly sought after for numerous biomedical and biotechnological *** example,it is essential that devices such as stents or heart valves in the blood stream of patients do not cause thrombosis or infection,or that biosensors do not lose their function due to adverse interactions with the bio environment.A general approach to the design of biointerfaces that addresses this need has been pursued over a number of years[1].It has two elements:(1)prevention of non-specific interfacial interactions,and(2)promotion of specific biointeractions required for the intended functioning of the *** practice this means preventing all interactions except for the desired one(s).With respect to the first point it should be appreciated that biological species such as proteins and cells have a natural affinity for the interfacial ***,the realization of a surface that eliminates the adsorption/adhesion of these species is extremely *** of PEO/PEG,other hydrophilic polymers(PVP,PHEMA),and zwitterionic polymers[2]to the surface is the most common strategy to achieve“bio-resistance”.Regarding the second point,the surface must be designed so that it interacts selectively and exclusively with the component(s)(proteins,cells)that will give the desired *** this purpose,“ligands”that bind these specific components are incorporated into the surface[3].

关键词： desired interfacial realization

Nonlinear waves in a fluid-filled thin viscoelastic tube

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Chinese Physics B 2010年第11期19卷 53-59页

作者：张善元张涛 Institute of Applied Mechanics and biomedical engineering Taiyuan University of Technology

In the present paper the propagation property of nonlinear waves in a thin viscoelastic tube filled with incom- pressible inviscid fluid is studied. The tube is considered to be made of an incompressible isotropic viscoelastic material described by Kelvin-Voigt model. Using the mass conservation and the momentum theorem of the fluid and radial dynamic equilibrium of an element of the tube wall, a set of nonlinear partial differential equations governing the propagation of nonlinear pressure wave in the solid-liquid coupled system is obtained. In the long-wave approximation the nonlinear far-field equations can be derived employing the reductive perturbation technique （RPT）. Selecting the expo- nent c~ of the perturbation parameter in Gardner-Morikawa transformation according to the order of viscous coefficient 7, three kinds of evolution equations with soliton solution, i.e. Korteweg-de Vries （KdV）-Burgers, KdV and Burgers equations are deduced. By means of the method of traveling-wave solution and numerical calculation, the propagation properties of solitary waves corresponding with these evolution equations are analysed in detail. Finally, as a example of practical application, the propagation of pressure pulses in large blood vessels is discussed.

关键词： fluid-filled tube solitary wave KdV-Burgers equation Kelvi-Vogit model

Analysis of kinematic data and determination of ground reaction force of foot in slow squat

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Acta Mechanica Sinica 2013年第1期29卷 143-148页

作者： Xu-Shu Zhang Yuan Guo Mei-Wen An Wei-Yi Chen Institute of Applied Mechanics and biomedical engineering Taiyuan University of Technology

In the present paper, the ground reaction force （GRF） acting on foot in slow squat was determined through a force measuring system, and at the same time, the kinematic data of human squat were obtained by analyzing the photographed image sequences. According to the height and body weight, six healthy volunteers were selected, three men in one group and the other three women in another group, and the fundamental parameters of subjects were recorded, including body weight, height and age, etc. Based on the anatomy characteristics, some markers were placed on the right side of joints. While the subject squatted at slow speed on the force platform, the ground reaction forces on the forefoot and heel for each foot were obtained through calibrated force platform. The analysis results show that the reaction force on heel is greater than that on forefoot, and double feet have nearly constant force. Moreover, from processing and analyzing the synchronously photographed image sequences in squat, the kinematic data of human squat were acquired, including mainly the curves of angle, angular velocity and angular acceleration varied with time for knee, hip and ankle joints in a sagittal plane. The obtained results can offer instructive reference for photographing and analyzing the movements of human bodies, diagnosing some diseases, and establishing in the future appropriate mathematical models for the human motion.

关键词： Ground reaction force. Force sensor. Kinematic data. Foot. Squat

Leader-follower formation of vehicles with velocity constraints and local coordinate frames

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Science China(Information Sciences) 2017年第7期60卷 81-95页

作者： Xiao YU Lu LIU Department of Mechanical and biomedical engineering City University of Hong Kong

This paper studies leader-follower formation control of networked nonholonomic vehicles of unicycle type. Each vehicle is subject to the velocity constraints consisting of saturated angular velocity and bounded linear velocity with positive-minimum value. Each vehicle is allowed to use its local coordinate frame, and the network topology is described by a directed graph containing a spanning tree. Two dynamic control laws satisfying the velocity constraints are developed respectively, such that the leader-follower formation defined in local coordinate frames can be achieved in two cases. The proposed control laws only require each vehicle to use the information of its neighbors in the network via local measurements and communication. Finally,effectiveness is illustrated by simulation results of an example.

关键词： formation control local coordinate frame mobile robot nonholonomic vehicle velocity constraint

Effect of carbon fiber on calcium phosphate bone cement

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中国有色金属学会会刊：英文版 2004年第4期14卷 769-774页

作者：戴红莲王欣宇黄健闫玉华李世普 biomedical Materials and engineering Research Center Wuhan University of Technology

The calcium phosphate cement (α-TCP/TTCP) was reinforced with oxidation-t reated carbon fibers. The effect of aspect ratio and content of carbon fiber on the compression strength and bending strength of the hardened body was discussed . The results show that the reinforcing effect is optimal as the aspect ratio is 375 and the additive amount is 0.3%(mass fraction). Under this condition,the c ompressive strength is increased by 55% (maximum 63.46 MPa),and the bending st rength is nearly increased by 100% (maximum 11.95 MPa),respectively. However,if the additive quantity and aspect ratio are too high,the effect of the carbon fibers is limited because it can not be dispersed uniformly in the hardened bod y. The biological evaluation indicates that the calcium phosphate cement reinfor ced by carbon fibers has good biocompatibility.

关键词：磷酸钙生物材料 α-TCP/TTCP 骨接合剂氧化处理碳纤维

Response enhancement of olfactory sensory neurons-based biosensors for odorant detection

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2009年第4期10卷 285-290页

作者： Chun-sheng WU Pei-hua CHEN Qing YUAN Ping WANG Biosensor National Special Laboratory MOE Key Laboratory of Biomedical Engineering Department of Biomedical Engineering Zhejiang University Hangzhou 310027 China

This paper presents a novel strategy for the response enhancement of olfactory sensory neurons (OSNs)-based biosensors by monitoring the enhancive responses of OSNs to odorants. An OSNs-based biosensor was developed on the basis of the light addressable potentiometric sensor (LAPS), in which rat OSNs were cultured on the surface of LAPS chip and served as sensing elements. LY294002, the specific inhibitor of phosphatidylinositol 3-kinase (PI3K), was used to enhance the responses of OSNs to odorants. The responses of OSNs to odorants with and without the treatment of LY294002 were recorded by LAPS. The results show that the enhancive effect of LY294002 was recorded efficiently by LAPS and the responses of this OSNs-LAPS hybrid biosensor were enhanced by LY294002 by about 1.5-fold. We conclude that this method can enhance the responses of OSNs-LAPS hybrid biosensors, which may provide a novel strategy for the bioelectrical signal monitor of OSNs in biosensors. It is also suggested that this strategy may be applicable to other kinds of OSNs-based biosensors for cellular activity detection, such as microelectrode array (MEA) and field effect transistor (FET).

关键词： Olfactory sensory neurons (OSNs) Response enhancement Light addressable potentiometric sensor (LAPS) Olfactory-based biosensor

In vivo measurement of NADH fluorescence lifetime in skeletal muscle via -ber-coupled time-correlated single photon counting

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Journal of Innovative Optical Health Sciences 2024年第1期17卷 121-134页

作者： Kathryn M.Priest Jacob V.Schluns Nathania Nischal Colton L.Gattis Jeffrey C.Wolchok Timothy J.Muldoon Department of biomedical engineering University of Arkansas FayettevilleARUSA

Nicotinamide adenine dinucleotide(NADH)is a cofactor that serves to shuttle electrons during metabolic processes such as glycolysis,the tricarboxylic acid cycle,and oxidative phosphorylation(OXPHOS).NADH is autofluorescent,and itsfluorescence lifetime can be used to infer metabolic dynamics in living ***-coupled time-correlated single photon counting(TCSPC)equipped with an implantable needle probe can be used to measure NADH lifetime in vivo,enabling investigation of changing metabolic demand during muscle contraction or tissue *** study illustrates a proof of concept for point-based,minimally-invasive NADHfluorescence lifetime measurement in *** muscle loss(VML)injuries were created in the left tibialis anterior(TA)muscle of male Sprague Dawley *** lifetime measurements were collected before,during,and after a 30 s tetanic contraction in the injured and uninjured TA muscles,which was subsequently-t to a biexponential decay model to yield a metric of NADH utilization(cytoplasmic vs protein-bound NADH,the A11/A22 ratio).On average,this ratio was higher during and after contraction in uninjured muscle compared to muscle at rest,suggesting higher levels of free NADH in contracting and recovering muscle,indicating increased rates of *** injured muscle,this ratio was higher than uninjured muscle overall but decreased over time,which is consistent with current knowledge of inflammatory response to injury,suggesting tissue regeneration has *** data suggest that-ber-coupled TCSPC has the potential to measure changes in NADH binding in vivo in a minimally invasive manner that requires further investigation.

关键词： Glycolysis oxidative phosphorylation energy metabolism volumetric muscle loss

Plasmonic biosensing based on non-noble-metal materials

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Chinese Chemical Letters 2018年第1期29卷 54-60页

作者： Jianhua Zhou Yangyang Wang Li Zhang Xuemeng Li Key Laboratory of Sensing Technology and biomedical Instruments of Guangdong Province Department of Biomedical Engineering School of Engineering Sun Yat-sen University

Plasmonic nanostructures can confine light through localized surface plasmon resonance （LSPR）, thereby enabling highly sensitive, label-free, and real-time physical and chemical sensing. Nowadays, the LSPR biosensing based on noble metal is still restricted in research laboratories, due to the limitations of their intrinsic properties, high prime price, and high process cost. Researchers thereby have paid attention to the non-noble metals and semiconductor materials in recent years. This review focuses on the research progress of non-noble-metal materials with nanostructures for plasmonic biosensing. Firstly, the physical and sensing principles of LSPR sensors are briefly introduced. Then, non-noble-metal materials, such as copper, aluminum, semiconductor, graphene and other materials, for plasmonic sensing are categorized and presented. Finally, a rational discussion about the future prospective of novel materials for plasmonic sensing is given.

关键词： Plasmonic biosensingLocalized surface plasmon resonanceNon-noble-metal nanomaterialCopperAluminumSemiconductorGraphene