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Nonlinear dynamics of self-oscillating polymer gels

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Science china(Technological sciences) 2010年第7期53卷 1862-1868页

作者： WANG PengFei1, ZHOU JinXiong1, LI MeiE2, XU Feng1,3 & LU TianJian1 1 Biomedical Engineering and Biomechanics Center, SV Laboratory, Xi’an Jiaotong university, Xi’an 710049, china 2 school of Materials Science and Engineering, Xi’an Jiaotong university, Xi’an 710049, china 3 HST Center for Biomedical Engineering, department of Medicine, Brigham and Women’s Hospital, Harvard medical school, Boston, 510660, USA 1. Biomedical Engineering and Biomechanics Center SV Laboratory Xi’an Jiaotong University Xi’an 710049 China2. School of Materials Science and Engineering Xi’an Jiaotong University Xi’an 710049 China3. HST Center for Biomedical Engineering Department of Medicine Brigham and Women’s Hospital Harvard Medical School Boston 510660 USA

Self-oscillating polymer gels driven by Belousov-Zhabotinsky (BZ) chemical reaction are a new class of functional gels that have a wide range of potential applications (e.g., autonomously functioning membranes, actuate artificial muscles). However, the precise control of these gels has been an issue due to limited investigations of the influences of key system parameters on the characteristics of BZ gels. To address this deficiency, we studied the self-oscillating behavior of BZ gels using the nonline-ar dynamics theory and an Oregonator-like model, with focus placed upon the influences of various system parameters. The analysis of the oscillation phase indicated that the dynamic response of BZ gels represents the classical limit cycle oscillation. We then investigated the characteristics of the limit cycle oscillation and quantified the influences of key parameters (i.e., ini-tial reactant concentration, oxidation and reduction rate of catalyst, and response coefficient) on the self-oscillating behavior of BZ gels. The results demonstrated that sustained limit cycle oscillation of BZ gels can be achieved only when these key pa-rameters meet certain requirements, and that the pattern, period and amplitude of the oscillation are significantly influenced by these parameters. The results obtained in this study could enable the controlled self-oscillation of BZ gels system. This has several potential applications such as controlled drug delivery, miniature peristaltic pumps and microactuators.

关键词： Belousov-Zhabotinsky reaction self-oscillating gels numerical simulation limit cycle parameter analysis

Embryonic hepatocyte transplantation for hepatic cirrhosis:Efficacy and mechanism of action

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World Journal of Gastroenterology 2012年第4期18卷 309-322页

作者： Wen-Ting Bin,Qing Xu,Xiao-Lin Shi,Laboratory of Reproductive Biology,department of Histology and Embryology,school of basic medical sciences,Capital medical university,Beijing 100069,china Li-Mei Ma,department of Histology and Embryology,Kunming medical university,Kunming 650031,Yunnan Province,china Wen-Ting Bin Qing Xu Xiao-Lin Shi Laboratory of Reproductive Biology Department of Histology and Embryology School of Basic Medical Sciences Capital Medical University Beijing 100069 China Li-Mei Ma Department of Histology and Embryology Kunming Medical University Kunming 650031 Yunnan Province China

AIM： To investigate the efficacy and mechanism of action of allogeneic embryonic hepatocyte transplantation for the treatment of hepatic cirrhosis. METHODS： Rat embryonic hepatocytes were characterized by examining cell markers. Wistar rats with CCl4-induced cirrhosis were randomly divided into two groups： a model group receiving continuous CCl4, and a cell transplantation group receiving continuous CCh and transplanted with embryonic fluorescent-labeled hepatocytes. In addition, a normal control group was composed of healthy rats. All rats were sacrificed after 2 wk following the initiation of the cell transplant. Ul- trasound, pathological analyses and serum biochemical tests were used to evaluate the efficacy of embryonic hepatocyte transplantation. To analyze the recovery status of cirrhotic hepatocytes and the signaling pathways influenced by embryonic hepatocyte transplantation, real-time polymerase chain reaction was performed to examine the mRNA expression of stellate activation-associated protein （STAP）, c-myb, ~ smooth muscle actin （^-SMA） and endothelin-1 （ET-1）. West- ern blotting and immunohistochemistry were employed to detect ^-SMA and ET-1 protein expression in hepatic tissues. RESULTS： Gross morphological, ultrasound and his- topathological examinations, serum biochemical tests and radioimmunoassays demonstrated that hepatic cir- rhosis was successfully established in the Wistar rats. Stem cell factor receptor （c-kit）, hepatocyte growth factor receptor （c-Met）, Nestin, ~ fetal protein, albu- min and cytokeratin19 markers were observed in the rat embryonic hepatocytes. Following embryonic hepa- tocyte transplantation, there was a significant reversal in the gross appearance, ultrasound findings, histo- pathological properties, and serum biochemical param- eters of the rat liver. In addition, after the activation of hepatic stellate cells and STAP signaling, ^-SMA, c-myb and ET-1 mRNA levels became significantly lower than in the untreated cirrhotic g

关键词： Embryonic hepatocytes Cirrhosis Stellateactivation-associated protein Endothelin-1 Cell trans-plantation

Hepatoprotective role of ganoderma lucidum polysaccharide against BCG-induced immune liver injury in mice

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World Journal of Gastroenterology 2002年第4期8卷 728-733页

作者： Guo-Liang Zhang Ye-Hong Wang Wei Ni Hui-Ling Teng Zhi-Bin Lin department of Pharmacology,school of basic medical sciences,Beijing university,Beijing 100083,china department of Pharmacology School of Basic Medical Sciences Beijing University Beijing 100083 China. yuankui@***

AIM: To examine the effect of ganoderma lucidumpolysaccharide (GLP) on the immune liver injuryinduced by BCG infection, and investigate therelationship between degrees of hepatic damage andNO production in ***: Immune hepatic injury was markedlyinduced by BCG-pretreatment (125 ***-1, 2-week, iv)or by BCG-pretreatment plus lipopolysaccharide (LPS,125 μ***-1, 12-hour, iv) in mice in *** induced by BCG-pretreated plus inflammatorycytokines mixture (CM), which was included TNF-α, IL1β, IFN-γ and LPS in culture medium in *** of GLP was performed by oral orincubating with culture medium at immune stimulisimultaneity. Liver damage was determined by activityof alanine aminotransferase (ALT) in serum and inhepatocytes cultured supernatant, by liver weightchanges and histopathological examination. NOproduction in the cultured supematant was determinedby the Griess reaction. Moreover, inducible nitric oxidesynthase (iNOS) protein expression was alsoexaminated by immunohistochemi1cal ***: Immune hepatic injury was markedly inducedby BCG or BCG plus inflammatory cytokines in BALB/cmice in vivoand in vitro. Under BCG-stimulated condition,augment of the liver weight and increase of the serum/supernatant ALT level were observed, as well asgranuloma forming and inflammatory cells soakage wereobserved by microscopic analysis within liver ***, NO production was also increased by BCG or/and CH stimuli in the culture supernatant, and a lot ofiNOS positive staining was observed in BCG-prestimulated hepatic sections. Application of GLPsignificantly mitigated hepatic tumefaction, decreasedALT enzyme release and NO production in serum/supernatant, improved the pathological changes ofchronic and acute inflammation induced by BCG-stimuliin mice. Moreover, the immunohistochemical resultshowed that GLP inhibited iNOS protein expression inBCG-immune hepatic damage ***: The present study indicates that NOparti

关键词：灵芝多糖卡介苗肝损伤肝脏保护动物实验作用机制

Diverse Effects of L-arginine on Cardiac Function of Rats Subjected to Myocardial Ischemia and Reperfusion in vivo

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Acta Biochimica et Biophysica Sinica 2007年第3期39卷 201-207页

作者： Xiaoliang WANG~1 Feng LIANG~2 Xiangying JIAOI Lei LIU~1 Xiaojie BAI~1 Meixia LI~1 Jianmin ZHI~3 Huirong LIU~1* 1 department of physiology,Shanxi medical university,Taiyuan 030001,china 2 department of Cardiothoracic Surgery,General Hospital of Taiyuan Iron and Steel Company Taiyuan 030003,china 3 department of physiology.Shanghai Jiaotong university.College of basic Medicine,Shanghai 200025,china department of physiology Shanxi Medical University Taiyuan 030001 China

In vivo administration of L-arginine at different time points during the course of myocardialischemia and reperfusion（MI/R）has been shown to differentially regulate postischemic *** is one of the most important indexes used to judge the degree of myocardial *** presentstudy attempted to determine whether in vivo administration of L-arginine at different stages of MI/R has adiverse influence on cardiac function of ischemic reperfused hearts and,if so,to investigate the *** adult rats were subjected to 30 min myocardial ischemia followed by 5 h *** L-arginine bolus was given either 10 min before and 50 min after reperfusion（early treatment）or3 h and 4 h after reperfusion（late treatment）.Early treatment with L-arginine markedly increased the leftventricular systolic pressure（LVSP）and dP/dtmax,and decreased myocardial nitrotyrosine *** strictcontrast,late treatment with L-arginine resulted in a significant decrease in LVSP and dP/dtmaxfrom 4 h to 5h after reperfusion,and increase in toxic peroxynitrite formation as measured by *** resultssuggest that the administration of L-arginine at different time points during the course of MI/R leads todiverse effects on cardiac *** supplementation decreased the nitrative stress and improvedleft ventricular ***,late treatment with L-arginine increased the formation of peroxynitriteand aggravated cardiac functional injury.

关键词： myocardial ischemia reperfusion cardiac function nitric oxide peroxynitrite

Salvianolic acid B protects endothelial cells from oxidant-mediated damage

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Salvianolic acid B protects endothelial cells from oxidant-m...

A non-linear finite element model of human L4-L5 lumbar spinal segment with three-dimensional solid element ligaments

两岸三地药理学与临床药理学术会议

作者： LI Xue-jun (department of Pharmacology, school of basic medical sciences, Peking university, Beijing 100083,china)

Objective To investigate the protective effects of Salvianolic acid B(Sal B)on hydrogen peroxide (HO)-induced injury in human umbilical vein endothelial cells(HUVECs).Sal B is considered as one of the most active anti-oxidant and the major pharmacological component of the herb,Salvia *** beneficial effects include hepatoprotection,elicitation of endothelium-dependent vasodilation,lowering blood pressure in hypertension,inhibition of HIV-1 replication and suppressing inflammatory cytokine-stimulated endothelial adhesiveness to human monocytic cells by its strong antioxidant *** Treatment with HO significantly decreased the cell viability and increased the lactate dehydrogenase(LDH)leakage that is an apoptotic *** with Sal B prevented significantly from HO-induced cell apopto- sis and other damages in a concentration-dependent *** mechanism of Sal B protection was studied with two-dimensional gel electrophoresis(2-DE)coupled to hybrid quadrupole time-of-flight mass spec- trometry(Q-TOF)mass *** Data base searching implicated glucose-regulated protein 78 (GRP78),a central regulator for ER stress,was up-regulated in Sal B-exposed *** exposure to Sal B,the level of activating transcription factor 4(ATF4)was raised,with a transient phosphorylation of the a subunit of eukaryotic translation initiation factor(eIF2α).Knock-down of GRP78 by siRNA signifi- cantly reduced protective effects of Sal *** These results suggest that Sal B-induced GRP78 up- regulation via phosphorylation of eIF2αand resultant translation of *** up-regulation of ER chaper- ones induced by Sal B may play an important role in protecting human endothelial cells from oxidative stress-induced cellular damage.

关键词： Sal B HUVECs H2O2

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Theoretical & Applied Mechanics Letters 2011年第6期1卷 75-80页

作者： Zhitao Xiao,1 Liya Wang,1 He Gong,1, ) Dong Zhu,2, ) and Xizheng Zhang3 1)department of Engineering Mechanics, jilin university, changchun 130012, china 2)department of Orthopaedic Trauma No.1, Hospital of jilin university, changchun 130012, china 3)Institute of medical Equipment, Academy of Military medical sciences, Tianjin 300161, china department of Engineering Mechanics Jilin University Changchun 130012 China department of Orthopaedic Trauma No.1 Hospital of Jilin University Changchun 130012 China Institute of medical Equipment Academy of Military Medical Sciences Tianjin 300161 China

This paper establishes a non-linear finite element model (NFEM) of L4-L5 lumbar spinal segment with accurate three-dimensional solid ligaments and intervertebral disc. For the purpose, the intervertebral disc and surrounding ligaments are modeled with four-nodal three-dimensional tetrahedral elements with hyper-elastic material properties. Pure moment of 10 N·m without preload is applied to the upper vertebral body under the loading conditions of lateral bending, backward extension, torsion, and forward flexion, respectively. The simulate relationship curves between generalized forces and generalized displacement of the NFEM are compared with the in vitro experimental result curves to verify NFEM. The verified results show that: (1) The range of simulated motion is a good agreement with the in vitro experimental data; (2) The NFEM can more effectively reffect the actual mechanical properties than the FE model using cable and spring elements ligaments; (3) The NFEM can be used as the basis for further research on lumbar degenerative diseases.

关键词： lumbar spine non-linear ligaments finite element analysis

Effect of C-myc Antisense Oligodeoxynucleotides on Hypoxia-induced Proliferation of Pulmonary Vascular Pericytes

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Journal of Huazhong university of Science and Technology(medical sciences) 2000年第3期20卷 194-196页

作者：王林熊密车东媛郑晓静 department of Pathology School of Basic Medical Sciences Tongji Medical University Wuhan department of Internal Medicine Tongji Hospital Tongji Medical University Wuhan

To study the effect of c myc antisense oligodeoxynucleotides (ODNs) on proliferation of pulmonary vascular pericytes (PC) induced by hypoxia, cell culture, dot hybridization using probe of digoxigenin 11 dUTP labeled cDNA, 3H thymidine incorporation, immunocytochemical technique and image analysis methods were used to observe the effect of c myc antisense ODNs on expression of c myc gene and proliferating cell nuclear antigen (PCNA), and 3H thymidine incorporation of PC induced by hypoxia. The results showed that hypoxia could significantly enhance the expression of c myc and PCNA ( P <0.01), and elevate 3H thymidine incorporation of PC ( P <0.01), but antisense ODNs could significantly inhibit the expression of c myc and PCNA ( P <0.05), and 3H thymidine incorporation of PC ( P <0.01). It was suggested that hypoxia could promote the proliferation of PC by up regulating the expression of c myc gene, but c myc antisense ODNs could inhibit hypoxia induced proliferation of PC by downregulating the expression of c myc gene.

关键词： antisense oligodeoxynucleotides hypoxia pericyte oncogene

ADVANCES IN STUDY ON MOLECULAR BIOLOGY OF MOUSE LEUKEMIA VIRUS IN china

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中国实验血液学杂志 1994年第4期2卷 349-353页

作者： CHENG Li YIN Lian-Hua(department of Pathophysiology, school of basic medical sciences, Shanghai medical university, Shanghai)

In china, Cheng et al firstly reported the es-tablishment of L6565 viral leukemia strain in 1966,and published a review of twelve mouse leukemiastrains, spontaneous or transplantable, establisheddomestically in 1983. ... 详细信息

关键词：实验血液学杂志

MEASUREMENTS OF INTRAOCULAR PRESSURE THROUGH0UT THE PREGNANCY IN PAKISTANI WOMEN

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Chinese medical sciences Journal 1997年第1期12卷 53-56页

作者： Imran Ahmad Qureshi(department of physiology, Rawalpindi medical College, Rawalpindi, Pakistan)(foreign student dorm, Shanghai medical university, 200032) department of physiology Rawalpindi Medical College Rawalpindi Pakistan. Physiology Department Basic Medical Sciences Institute Jinnah Postgraduate Medical Centre Karachi Pakistan.

Background. Decrease in intraocular pressure (IOP) during pregnancy has been reported by previous studies,but amount of decrease varies from study to study. Moreover,previous studies have concentrated on the last trimester of pregnancy or one reading per trimester. IOP changes throughout the pregnancy have never been described. Therefore,the present study was planned to determine IOP throughout the pregnan cy,after placing control on IOP affecting *** and methods. Thirty-six pregnant and same numbers of non-pregnanat women of the same age group were studied. IOP measurements were taken at four week intervals throughout the pregnancy,with the Goldmann applanation ***. As compared to control subjects,up to 8th week,IOP remained the same. At 12th week,it becomes significantly lower. The IOP differences between fIrst and second (P<0. 05),and second and third (P<0. 001 ) trimesters of pregnancy were significant. In every subject, IOP decreased during ***,there were variations among individuals in the extent of IOP decrease Conclusbos. With advancing pregnancy, intraocular pressure decreases. Knowledge of the normal level of intraocular pressure in various stages of pregnancy may help glaucoma screeners.

关键词： ocular pressure pregnancy tonometry