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Dynamic expression of glucose transporters 1 and 3 in the brain of diabetic rats with cerebral ischemia reperfusion

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Chinese Medical Journal 2009年第17期122卷 1996-2001页

作者： ZHANG Wen-wen ZHANG Li hou wei-kai XU Yu-xin XU Hua LOU Fu-chen ZHANG Ying WANG Qian Department of Endocrinology Qilu Hospital of ShandongUniversity Jinan Shandong 250012 China Department of Endocrinology Shandong Traffic Hospital JinanSbandong 250013 China

Background Blood glucose control improves the outcome of diabetic patients with stroke, but the target range of blood glucose control remains controversial. The functional recruitment of ischemia penumbra is extremely important to the recovery after stroke. The present study aimed to explore the expression of brain-type glucose transporters （GLUT1 and GLUT3） in cerebral ischemic penumbra at different blood glucose levels and different ischemic-reperfusion time in diabetic hypoxia-ischemia rats. The results might provide an experimental basis for clinical treatment of diabetic patients with stroke. Methods The Wistar rats included in this study were randomly assigned to 4 groups （50 rats each）： normal control group （NC）, uncontrolled diabetic group （DM1）, poorly-controlled diabetic group （DM2）, and well-controlled diabetic group （DM3）. Diabetic rats were induced by single intraperitoneal injection of streptozotocin, and the focal ischemic rat model of middle artery occlusion （MCAO） was made by insertion of fishing thread in 6 weeks after the establishment of the diabetic model. Each group was divided into 5 subgroups （10 rats each）： four focal ischemic subgroups at different ischemic-reperfusion time （at 3,12, 24 and 72 hours after reperfusion, respectively） and one sham-operated subgroup. The mRNA and protein expression of GLUT1 and GLUT3 was assessed by RT-PCR and Western blotting, respectively. Results There was significant difference in the mRNA expression of GLUT1 and GLUT3 between the four focal ischemic subgroups and the sham-operated subgroup at different reperfusion time in each group. The mRNA expression of GLUT1 and GLUT3 in the 4 ischemic groups began to increase at 3 hours, peaked at 24 hours after reperfusion and maintained at a higher level even at 72 hours compared with that of the sham-operated subgroup. The mRNA expression of GLUT1 increased more significantly than that of GLUT3. The mRNA expression of GLUT1 and GLUT3 was significantly different bet

关键词： diabetes mellitus cerebral ischemia reperfusion ischemia penumbra," glucose transporter

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深入实施西部大开发战略评估及政策建议

开发研究 2014年第1期 1-7页

作者：魏后凯赵勇中国社会科学院城市发展与环境研究所北京100028

深入实施西部大开发战略以来,西部地区发展取得了长足的进步,与东部地区及其他区域的相对差距不断缩小。但是,目前西部地区的贫困问题仍然突出,同步实现小康难度较大,基本公共服务均等化推进缓慢,城乡收入差距较大,城镇化水平和质量较低... 详细信息

深入实施西部大开发战略以来,西部地区发展取得了长足的进步,与东部地区及其他区域的相对差距不断缩小。但是,目前西部地区的贫困问题仍然突出,同步实现小康难度较大,基本公共服务均等化推进缓慢,城乡收入差距较大,城镇化水平和质量较低,生态补偿机制仍有待完善。进一步深入实施西部大开发战略,需要实行分类管理的区域支持政策体系,制定和完善西部大开发政策实施细则,建立健全资源开发和生态补偿机制,有效推进西部特色新型城镇化,积极推动基本公共服务均等化,进一步加大沿边开发开放力度,以确保在2020年与全国同步建成小康社会。

关键词：西部大开发战略评估政策建议

Differentiation of bone marrow-derived mesenchymal stem cells from diabetic patients into insulin-producing cells in vitro

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Chinese Medical Journal 2007年第9期120卷 771-776页

作者： SUN Yu CHEN Li hou Xin-guo hou wei-kai DONG Jian-jun SUN Lei TANG Kuan-xiao WANG Bin SONG Jun LI Hui WANG Ke-xin Department of Endocrinology Qilu Hospital Shandong University Jinan 250012 China Yuhuangding Hospital Yantai 264000 China

Bckground Stem cells, which have the ability to differentiate into insulin-producing cells （IPCs）, would provide a potentially unlimited source of islet cells for transplantation and alleviate the major limitations of availability and allogeneic rejection. Therefore, the utilization of stem cells is becoming the most promising therapy for diabetes mellitus （DM）. Here, we studied the differentiation capacity of the diabetic patient＇s bone marrow-derived mesenchymal stem cells （MSCs） and tested the feasibility of using MSCs for β-cell replacement. Methods Bone marrow-derived MSCs were obtained from 10 DM patients （5 type 1 DM and 5 type 2 DM） and induced to IPCs under a three-stage protocol. Representative cell surface antigen expression profiles of MSCs were analysed by flow cytometric analysis. Reverse transcription-polymerase chain reaction （RT-PCR） was performed to detect multiple genes related to pancreatic β-cell development and function. The identity of the IPCs was illustrated by the analysis of morphology, ditizone staining and immunocytochemistry. Release of insulin by these cells was confirmed by immunoradioassay. Results Flow cytometric analysis of MSCs at passage 3 showed that these cells expressed high levels of CD29 （98.28%）, CD44 （99.56%） and CD106 （98.34%）. Typical islet-like cell clusters were observed at the end of the protocol （18 days）. Ditizone staining and immunohistochemistry for insulin were both positive. These differentiated cells at stage 2 （10 days） expressed nestin, pancreatic duodenal homeobox-1 （PDX-1）, Neurogenin3, Pax4, insulin, glucagon, but at stage 3 （18 days） we observed the high expression of PDX-1, insulin, glucagon. Insulin was secreted by these cells in response to different concentrations of glucose stimulation in a regulated manner （P〈0.05）. Conclusions Bone marrow-derived MSCs from DM patients can differentiate into functional IPCs under certain conditions in vitro. Using diabetic patient＇s own bone marrow-derived MSC

关键词： diabetes mellitus mesenchymal stem cells insulin transdifferentiation

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迁入潜能与城市增长

中国软科学 2020年第8期 78-90页

作者：苏红键魏后凯中国社会科学院农村发展研究所北京100732 中国社会科学院大学北京102488

本文结合城市增长理论和人口迁移理论的观点,构建了迁入潜能指标,以此衡量本地区及其他地区人口向城市迁入的潜在供给水平,并结合综合效用指标,共同解释中国快速城镇化进程中的城市增长问题。研究结果发现:随着中国城市规模增长,城市规... 详细信息

本文结合城市增长理论和人口迁移理论的观点,构建了迁入潜能指标,以此衡量本地区及其他地区人口向城市迁入的潜在供给水平,并结合综合效用指标,共同解释中国快速城镇化进程中的城市增长问题。研究结果发现:随着中国城市规模增长,城市规模体系不断优化,规模位序系数逐渐接近世界平均水平;迁入潜能指标能够很好地解释城市增长差异,对迁入潜能指标的分解发现基期城市规模比按距离加权的本地区和其他地区人口规模的促进作用更大;收入水平和城市环境通过影响综合效用进而影响迁入意愿和城市增长,影响系数略低于迁入潜能;城市行政等级与沿海城市虚拟变量均与城市增长正相关。未来推进城镇化进程中,各个城市可以通过加强对其迁入潜能的考察,提高城市人口预测和规划的科学性,制定合理的城镇化战略。

关键词：迁入潜能综合效用城市增长人口迁移

促进区域产业有序转移与协调发展的碳减排目标设计

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中国人口·资源与环境 2013年第1期23卷 55-62页

作者：成艾华魏后凯中南民族大学经济学院湖北武汉430074 中国社会科学院城市发展与环境研究所北京100005

当前,在扩大内需、转变经济发展方式的大背景下,跨区域产业转移已成为中国区域政策中促进区域协调发展的重要手段。如何根据中国各区域碳排放的差异性,合理设计有差别的碳减排目标,促进区域产业有序转移与协调发展,是当前需要考虑的一... 详细信息

当前,在扩大内需、转变经济发展方式的大背景下,跨区域产业转移已成为中国区域政策中促进区域协调发展的重要手段。如何根据中国各区域碳排放的差异性,合理设计有差别的碳减排目标,促进区域产业有序转移与协调发展,是当前需要考虑的一个重要战略问题。本文首先采用工业部门市场份额指标来反映地区产业转移状况,并按产业转移情况和工业化水平把中国划分为净转入、净转出和其他中西部三类区域;然后运用改进的LMDI模型,从碳排放系数、碳排放强度、经济结构及经济规模四个方面对不同区域碳排放效应进行分解,明确了不同区域碳排放的差异特征。在此基础上,根据未来中国区域碳减排政策应坚持"共同而有区别的责任原则",建立了新的区域碳减排指标分配框架,即对净转入、净转出和其他中西部三类区域分别实行以结构调整为主的强制减排、以降低能源强度为主的强制减排和发展减排的差异化目标,促进东部地区产业转型升级与中西部地区跨越式绿色发展。

关键词：区域产业转移碳排放协调发展减排目标

Influence of blood glucose on the expression of glucose transporter proteins 1 and 3 in the brain of diabetic rats

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Chinese Medical Journal 2007年第19期120卷 1704-1709页

作者： hou wei-kai XIAN Yu-xin ZHANG Li LAI Hong hou Xin-guo XU Yu-xin YU Ting XU Fu-yu FU Chun-li ZHANG Wen-wen CHEN Li Department of Endocrinology Qilu Hospital of Shandong University Jinan 250012 China Department of Infectious Diseases Affiliated Hospital of Qingdao University Medical School Qingdao 266003 China Department of Pathology Shandong University Medical School Jinan 250013 China

Background The delivery of glucose from the blood to the brain involves its passage across the endothelial cells of the blood-brain barrier （BBB）, which is mediated by the facilitative glucose transporter protein 1 （GLUT1）, end then across the neural cell membranes, which is mediated by GLUT3. This study aimed to evaluate the dynamic influence of hyperglycemia on the expression of these GLUTs by measuring their expression in the brain at different blood glucose levels in e rat model of diabetes. This might help to determine the proper blood glucose threshold level in the treatment of diabetic apoplexy. Methods Diabetes mellitus was induced with streptozotocin （STZ） in 30 rats. The rats were randomly divided into 3 groups： diabetic group without blood glucose control （group DM1）, diabetic rats treated with low dose insulin （group DM2） end diabetic rats treated with high dose insulin （group DM3）. The mRNA end protein levels of GLUT1 end GLUT3 were essayed by reverse trenscriptese-polymerese chain reaction （RT-PCR） end immunohistochemistry, respectively. Results Compared with normal control rats, the G/UT1 mRNA was reduced by 46.08%, 29.80%, 19.22% （P〈0.01） in DM1, DM2, end DM3 group, respectively; end the GLUT3 mRNA was reduced by 75.00%, 46.75%, end 17.89% （P〈0.01） in DM1, DM2, end DM3 group, respectively. The abundance of GLUT1 end GLUT3 proteins had negative correlation with the blood glucose level （P〈0.01）. The density of microvessels in the brain of diabetic rats did not change significantly compared with normal rats. Conclusions Chronic hyperglycemia downreguletes G/UT1 end GLUT3 expression at both mRNA end protein levels in the rat brain, which is not due to the decrease of the density of microvessels. The downreguletion of G/UT1 end GLUT3 expression might be the adaptive reaction of the body to prevent excessive glucose entering the cell that may lead to cell damage.

关键词： diabetes mellitus glucose transporter protein blood glucose brain transcription regulation

A 26.5–29.5-GHz Doherty PA with enhanced linearity and efficiency based on adaptive bias circuit for 5G MIMO arrays

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Science China(Information Sciences) 2024年第7期67卷 341-342页

作者： Long WANG Jixin CHEN Debin hou Xiaojie XU wei HONG State Key Laboratory of Millimeter Waves Southeast University Misic Microelectronics Co. Ltd.

Power amplifiers (PAs) play a crucial role in achieving key performance metrics such as efficiency, power, and ***, in the millimeter-wave frequency range, the performance of active devices rapidly deteriorates with increasing frequency. The typical Doherty architecture, through load modulation techniques, can achieve high back-off efficiency [1]. To enhance the linearity of the PA, adaptive bias circuits (ADBs) have been widely adopted [2, 3].

关键词： POWER-AMPLIFIER

Reinforcement Learning Navigation for Robots Based on Hippocampus Episode Cognition

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Journal of Bionic Engineering 2024年第1期21卷 288-302页

作者： Jinsheng Yuan wei Guo Zhiyuan hou Fusheng Zha Mantian Li Pengfei Wang Lining Sun State Key Laboratory of Robotics and System Harbin Institute of Technology(HIT)Harbin 150001China Shenzhen Academy of Aerospace Technology Shenzhen 518057China School of Mechanical and Electrical Engineering Lanzhou University of TechnologyLanzhou 730050China

Artificial intelligence is currently achieving impressive success in all ***,autonomous navigation remains a major challenge for *** learning is used for target navigation to simulate the interaction between the brain and the environment at the behavioral level,but the Artificial Neural Network trained by reinforcement learning cannot match the autonomous mobility of humans and *** hippocampus–striatum circuits are considered as key circuits for target navigation planning and *** paper aims to construct a bionic navigation model of reinforcement learning corresponding to the nervous system to improve the autonomous navigation performance of the *** ventral striatum is considered to be the behavioral evaluation region,and the hippocampal–striatum circuit constitutes the position–reward *** this paper,a set of episode cognition and reinforcement learning system simulating the mechanism of hippocampus and ventral striatum is constructed,which is used to provide target guidance for the robot to perform autonomous *** with traditional methods,this system reflects the high efficiency of learning and better Environmental *** research is an exploration of the intersection and fusion of artificial intelligence and neuroscience,which is conducive to the development of artificial intelligence and the understanding of the nervous system.

关键词： Episode cognition Reinforcement learning Hippocampus Robot navigation

DC Traction Power Supply System Based on Modular Multilevel Converter Suitable for Energy Feeding and De-icing

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CSEE Journal of Power and Energy Systems 2024年第2期10卷 649-659页

作者： Lingxi hou Shuqing Zhang Yingdong wei Xiaoqian Li Qirong Jiang Mingrui Li weirui Li Department of Electrical Engineering Tsinghua UniversityBeijing 100084China

A novel DC traction power supply system suitable for energy feeding and de-icing is proposed in this paper for an urban rail transit catenary on the basis of the full bridge submodule (FBSM) modular multilevel converter (MMC). The FBSM-MMC is a novel type of voltage source converter (VSC) and can directly control the output DC voltage and conduct bipolar currents, thus flexibly controlling the power flow of the urban rail transit catenary. The proposed topology can overcome the inherent disadvantages of the output voltage drop in the diode rectifier units, increase the power supply distance and reduce the number of traction substations. The flexible DC technology can coordinate multiple FBSM-MMCs in a wide area and jointly complete the bidirectional control of catenary power flow during the operation of the electric locomotive, so as to realize the local consumption and optimal utilization of the recovered braking energy of the train. In addition, the FBSM-MMCs can also adjust the output current when the locomotive is out of service to prevent the catenary from icing in winter. The working modes of the proposed topology are illustrated in detail and the control strategy is specially designed for normal locomotive operations and catenary de-icing. Simulation cases conducted by PSCAD/EMTDC validate the proposed topology and its control strategy.

关键词： DC traction power supply system de-icing for catenary energy feeding modular multilevel converter based on full-bridge submodules(FBSM-MMC) urban rail transit