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Activity of Ginkgo biloba Extract and Quercetin on Thrombomodulin Expression and Tissue-type Plasminogen Activator Secretion by Human Umbilical Vein Endothelial Cells

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Biomedical and Environmental Sciences 2006年第4期19卷 249-253页

作者： WEN-JUN LAN xiao-xiang zheng Key Laboratory for Biomedical Engineering of Ministry of Education of China Zhejiang University （ Yuquan Campus） Hangzhou 310027 Zhejiang China

Objective In order to investigate the pharmacological properties of Ginkgo biloba extract （GBE） on improving blood circulation, the regulating action of GBE and quercetin （a main flavonoid ingredient in GBE） on thrombomodulin （TM） expression and tissue-type plasminogen activator （t-PA） secretion was studied. Methods Using flow cytometer and gel image system respectively, we evaluated the TM expression and the t-PA secretion by human umbilical vein endothelial cells （HUVECs） in vitro. Results The increase of TM expression on HUVECs surface was induced by GBE rather than quercetin in a dose- and time-dependent manner. Both GBE and quercetin increased the t-PA release significantly. Conclusion The effect of GBE on improving blood circulation may be partly attributed to its promoting TM expression and t-PA secretion by endothelial ceils, and quercetin participated in the effect of GBE on t-PA secretion. However, the action of GBE on increasing TM expression needs further study.

关键词： Ginkgo biloba extract Quercetin Thrombomodulin Tissue-type plasminogen activator

Inhibition of Excitatory Amino Acid Efflux Contributes to Protective Effects of Puerarin Against Cerebral Ischemia in Rats

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Biomedical and Environmental Sciences 2007年第4期20卷 336-342页

作者： xiao-HONG XU xiao-xiang zheng QIONG ZHOU HUI LI College of Chemistry and Life Sciences Zhejiang Normal University Jinhua 321004 Zhejiang China Department of Biomedical Engineering Zhejiang University Yuquan Campus Hangzhou 310013 Zhejiang China College of Science and Technology of Zhejiang Hangzhou 310013 Zhejiang China

To investigate whether the protective effects of puerarine （Pur） against cerebral ischemia is associated with depressing the extracellular levels of amino acid transmitters in brain of rats. Methods Male Sprague-Dawley rats were subjected to transient middle cerebral artery occlusion （MCAO） for 60 min followed by 24 h reperfusion. Put （50, 100 mg/kg, i.p.） was administered at the onset of MCAO. The infarct rate and edema rate were detected on TTC （2,3,5-triphenyltetrazolium chloride）-stained coronal sections. The extracellular levels of amino acid transmitters were monitored in striatum of rats with ischemic/reperfusion injury using in vivo microdialysis technique. Furthermore, the protective effects of Pur against glutamate-induced neurotoxicity were detected. Glutamate-induced apoptotic and necrotic cells in hippocampus were estimated by flow cytometric analysis of Annexin-V and PI labeling cells. Results Pur （100 mg/kg） significantly decreased infarct size by 31.6% （P〈0.05）, reduced edema volume （P〈0.05）, and improved neurological functions （P〈0.05） following MCAO. In these rats, the ischemia-induced extracellular levels of aspartate （Asp）, glutamate （Glu）, γ-aminobutyric acid （GABA）, and taurine （Tau） were significantly reduced in striatum of vehicle-treated animals by 54.7%, 56.7%, 75.8%, and 68.1% （P〈0.01 and P〈0.05）. Pur reduced the peak values of Glu and Asp more obviously than those of GABA and Tau, and the rate of Glu/GABA during MCAO markedly decreased in Pur-treated MCAO rats, compared with the vehicle-treated MCAO rats. Meanwhile, apoptosis and necrosis induced by Glu in cultured hippocampal neurons were significantly reduced after Pur treatment. Conclusion Acute treatment with Put at the onset of occlusion significantly depresses ischemia-induced efflux of amino acids, especially, excitotoxicity in the striatum, a mechanism underlying the neuroprotective effect on cellular survival.

关键词： Cerebral ischemia Puerarin Microdialysis Amino acid transmitter Neuroprotection

Three-dimensional tracking of GLUT4 vesicles in TIRF microscopy

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第2期9卷 232-240页

作者： xiang-ping WU Jie-yue LI Ying-ke XU Ke-di XU xiao-xiang zheng Department of Biomedical Engmeermg Zhejiang University Hangzhou 310027 China College of Information Engineering China Jiliang University Hangzhou 310018 China

TIRF microscopy has provided a means to view mobile granules within 100 nm in size in two *** quantitative analysis of the position and motion of those granules requires an appropriate tracking *** this paper,we present a new tracking algorithm combined with the unique features of *** a fluorescence correction procedure was processed to solve the problem of fluorescence bleaching over *** granules were then segmented from a time-lapse image stack by an adaptive background subtraction *** filter was introduced to estimate and track the granules that allowed reducing searching range and hence greater reliability in tracking *** the tracked granules were located in x-y plane,the z-position was indirectly inferred from the changes in their *** the experiments the algorithm was applied in tracking GLUT4 vesicles in living adipose *** results indicate that the algorithm has achieved robust estimation and tracking of the vesicles in three dimensions.

关键词： GLUT4 Total internal reflection fluorescence (TIRF) microscopy Adaptive background subtraction Kalman filter Fluorescence correction

Effects of cosolvent on formation and morphology of microspheres in precipitation polymerization of divinylbenzene in supercritical carbon dioxide

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Chinese Chemical Letters 2011年第4期22卷 489-492页

作者： Chun Sheng LiJing Cui Liang xiao Li Zhu xiang zheng Kong Key Laboratory of Fluorine Chemistry and Chemical Materials of Shandong Province College of Chemistry and Chemical Engineering University of Jinan Jinan 250022 China

Precipitation polymerizations of divinylbenzene（DVB） in pure supercritical carbon dioxide,and parallel runs with presence of a cosolvent were carried *** results showed that use of acetone as the cosolvent contributed greatly to the formation of the monodisperse *** microspheres,with obviously higher uniformity than reported up to date,were achieved using 6-7 mL of acetone in a reactor of 50 mL with DVB concentration of 0.4 mol/L under 16 MPa,a much lower pressure than previously reported without use of cosolvent.

关键词： Polydivinylbenzene microspheres Precipitation polymerization Supercritical carbon dioxide Cosolvent

Neural decoding based on probabilistic neural network

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2010年第4期11卷 298-306页

作者： Yi YU Shao-min ZHANG Huai-jian ZHANG xiao-chun LIU Qiao-sheng ZHANG xiao-xiang zheng Jian-hua DAI Qiushi Academy for Advanced Studies Zhejiang University Hangzhou 310027 China College of Biomedical Engineering and Instrument Science Zhejiang University Hangzhou 31002 7 China Key Laboratory of Biomedical Engineering of Ministry of Education Zhejiang University Hangzhou 310027 China College of Computer Science and Technology Zhejiang University Hangzhou 310027 China

Brain-machine interface (BMI) has been developed due to its possibility to cure severe body paralysis. This technology has been used to realize the direct control of prosthetic devices,such as robot arms,computer cursors,and paralyzed muscles. A variety of neural decoding algorithms have been designed to explore relationships between neural activities and movements of the limbs. In this paper,two novel neural decoding methods based on probabilistic neural network (PNN) in rats were introduced,the PNN decoder and the modified PNN (MPNN) decoder. In the ex-periment,rats were trained to obtain water by pressing a lever over a pressure threshold. Microelectrode array was implanted in the motor cortex to record neural activity,and pressure was recorded by a pressure sensor synchronously. After training,the pressure values were estimated from the neural signals by PNN and MPNN decoders. Their per-formances were evaluated by a correlation coefficient (CC) and a mean square error (MSE). The results show that the MPNN decoder,with a CC of 0.8657 and an MSE of 0.2563,outperformed the traditionally-used Wiener filter (WF) and Kalman filter (KF) decoders. It was also observed that the discretization level did not affect the MPNN performance,indicating that the MPNN decoder can handle different tasks in BMI system,including the detection of movement states and estimation of continuous kinematic parameters.

关键词： Brain-machine interfaces (BMI) Neural decoding Probabilistic neural network (PNN) Microelectrode array

Unconventional Fluorescent and Multi-responsive Polysiloxane:Synthesis,Characterization and Biological Applications

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Chinese Journal of Polymer Science 2024年第5期42卷 579-590,I0006页

作者： xiao-Di Li Shu-Sheng Li Xu-Bao Jiang xiao-Li Zhu xiang zheng Kong College of Chemistry and Chemical Engineering University of JinanJinan250022China College of Chemical Engineering Tianjin UniversityTianjin300072China Foshan(Southern China)Institute for New Materials Foshan528200China

Owing to their high significance in fundamental study and diverse applications,stimuli-responsive and fluorescent polymers,particularly those with cluster-triggered emission(CTE)featured by non-conjugated chromophores,have drawn tremendous attention in recent *** this work,fluorescent and multi-responsive polysiloxane(FRPS)was synthesized by hydrolytic condensation polymerization of 3-aminopropyl methyl diethoxysilane(APMS)with 3-(N-isopropyl propionamide)iminopropyl methyl diethoxysilane(APMS-NIP),which was formed in situ through aza-Michael addition between APMS and N-isopropyl *** was not only highly sensitive to temperature,pH and CO_(2) in water,but also showed an enhanced and stimuli-adjustable fluorescence *** effects of monomer feeding,pH and CO_(2) on its lower critical solution temperature and fluorescent property were *** fluorescence emission was ascribed to CTE *** addition,FRPS was shown to be highly potential as physiological indicator for cell imaging,and for controlled release and trace detection of *** study provides therefore a type of stimuli-responsive and fluorescent material for potential applications in biomedical fields,and it is also of great significance for understanding of the fluorescence mechanism of polysiloxane-based stimuli-responsive polymers.

关键词： Polysiloxane Multi-responsiveness Cluster-triggered emission Cell imaging Controlled drug release

Unconventional Fluorescent and Multi-responsive Polyethyleneimine with LCST and UCST Behavior:Synthesis,Characterization and Biological Applications

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Chinese Journal of Polymer Science 2024年第6期42卷 826-837页

作者： Feng-Ming Yin Li-Li Wu Shu-Sheng Li xiao-Na Pan xiao-Li Zhu Xu-Bao Jiang xiang zheng Kong College of Chemistry and Chemical Engineering University of JinanJinan250022China Shandong Institute for Product Quality Inspection Jinan250102China College of Chemical Engineering Tianjin UniversityTianjin300072China

Non-aromatic fluorescent and multi-responsive materials,exhibiting inherent fluorescence emission and controlled phase change,have garnered significant attention in recent ***,the underlying interaction between their fluorescent properties and phase transition remains *** this study,we synthesized a series of catalyst-free aza-Michael addition-based polyethyleneimine(RFPEI)materials by reacting polyethyleneimine(PEI)with N-isopropyl acrylamide(NIPAM).The resulting RFPEI was comprehensively characterized,and demonstrated dual-phase transition behavior(LCST and UCST)in water,which could be finely tuned by adjusting its composition or external factors such as ***,upon UV irradiation(365 nm),RFPEI exhibited strong fluorescence *** further investigated the effects of NIPAM grafting percentage to PEI,polymer concentration,and pH on the LCST/UCST and fluorescent properties of RFPEI aqueous ***,we showcased the great potential of RFPEI as a versatile tool for physiological cell imaging,trace detection,and controlled release of *** study presents a novel class of stimuli-responsive fluorescent materials with promising applications in the field of biomedicine.

关键词： Polyethyleneimine Multi-responsiveness Intrinsic fluorescence emission Cell imaging Controlled drug release

A bidirectional brain-computer interface for effective epilepsy control

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Journal of Zhejiang University-Science C(Computers and Electronics) 2014年第10期15卷 839-847页

作者： Yu QI Fei-qiang MA Ting-ting GE Yue-ming WANG Jun-ming ZHU Jian-min ZHANG xiao-xiang zheng Zhao-hui WU Qiushi Academy for Advanced Studies Zhejiang University Department of Computer Science Zhejiang University Second Affiliated Hospital of Zhejiang University College of Medicine College of Biomedical Engineering and Instrument Science Zhejiang University

Brain-computer interfaces(BCIs) can provide direct bidirectional communication between the brain and a machine. Recently, the BCI technique has been used in seizure control. Usually, a closed-loop system based on BCI is set up which delivers a therapic electrical stimulus only in response to seizure onsets. In this way, the side effects of neurostimulation can be greatly reduced. In this paper, a new BCI-based responsive stimulation system is proposed. With an efficient morphology-based seizure detector, seizure events can be identified in the early stages which trigger electrical stimulations to be sent to the cortex of the brain. The proposed system was tested on rats with penicillin-induced epileptic seizures. Online experiments show that 83% of the seizures could be detected successfully with a short average time delay of 3.11 s. With the therapy of the BCI-based seizure control system, most seizures were suppressed within 10 s. Compared with the control group, the average seizure duration was reduced by 30.7%. Therefore, the proposed system can control epileptic seizures effectively and has potential in clinical applications.

关键词： Brain-computer interface Epilepsy Seizure detection Responsive neurostimulation

Numerical investigation on dynamic response of the screen mesh in vibrating screening through DEM-FEM co-simulation

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Particuology 2024年第4期87卷 205-217页

作者： Huan Zhang xiao zheng Weimin Jing Key Laboratory of MetallurgicalEquipment and Control Technology Ministry of EducationWuhan University of Science and TechnologyWuhan430081 China Hubei Key Laboratory of Mechanical Transmssion and Manufacturing Engineering Wuhan University of Science and TechnologyWuhan430081China College of Mechanical and Vehicle Engineering Chongqing UniversityChongqing400044China

Dynamic response of the screen mesh is of great significance in the optimum vibrating screen *** this paper,based on the DEM-FEM co-simulation method,the effect of screening parameters on the dynamic response of the screen mesh is explored and the mechanism is revealed on the particle ***,a virtual experiment on a linear vibrating screen was carried out to analyze the screening pa-rameters'effect with both impact load and sustained stress inflicted on the screen ***,the time-domain evolution regularity of the screen mesh LVA(Local Vibration Amplitude)under different particle plugging conditions was investigated based on the ***,the influence of screening parameters on LVA and its distribution was *** results show that the screening parameters can greatly affect the screen mesh LVA and its distribution by changing the movement of the granular material and the particle penetration probability,which provides an important basis for the optimal design of the screen mesh and its supporting structure.

关键词： Vibrating screen Dynamic response DEM-FEM Screening parameters Local vibration amplitude