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中国病理生理杂志 2012年第11期 2093-2094页

作者： HE Jin-long1,2,ZOU Ming-hui2,ZHU Yi1(1department of physiology and Pathophysiology,peking university health sciences center,beijing 100191,china 2Section of Molecular Medicine,department of Medicine,university of Oklahoma health sciences center,Oklahoma City,OK 73104,USA)

AIM:Aberrant activation of thromboxane A2(TXA2)receptor(TPr)is reported to cause vascular inflammation and *** TPr activation instigates vascular inflammation remains poorly *** aim of the present study was to determi... 详细信息

关键词： IKK ROCK B phosphorylation

Constraints on smoothness parameter and dark energy using observational H(z) data

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Research in Astronomy and Astrophysics 2011年第2期11卷 125-136页

作者： Hao-Ran Yu1,Tian Lan1,Hao-Yi Wan2,Tong-Jie Zhang1,3 and Bao-Quan Wang4 1 department of Astronomy,beijing Normal university,beijing 100875,china 2 Business Office,beijing Planetarium,beijing 100044,china 3 center for High Energy Physics,peking university,beijing 100871,china 4 department of Physics,Dezhou university,Dezhou 253023,china department of Astronomy Beijing Normal University Beijing 100875 China Business Office Beijing Planetarium Beijing 100044 China center for High Energy Physics Peking University Beijing 100871 China department of Physics Dezhou University Dezhou 253023 China

With large-scale homogeneity,the universe is locally inhomogeneous,clustering into stars,galaxies and larger *** property is described by the smoothness parameter α which is defined as the proportion of matter in the form of intergalactic *** we consider the inhomogeneities over a small scale,there should be modifications of the cosmological distances compared to a homogenous *** and Roeder developed a second-order ordinary differential equation（D-R equation） that describes the angular diameter distance-redshift relation for inhomogeneous cosmological ***,we may obtain the D-R equation for observational H（z） data（OHD）.The density-parameter ΩM,the state of dark energy ω,and the smoothness-parameter α are constrained by a set of OHD in a spatially flat XCDM universe as well as a spatially flat XCDM *** using a χ2 minimization method,we get α = 0.81＋0.19-0.20 and ΩM = 0.32＋0.12-0.06 at the 1σ confidence *** we assume a Gaussian prior of ΩM = 0.26 ± 0.1,we get α = 0.93＋0.07-0.19 and ΩM = 0.31＋*** the XCDM model,α is constrained to α≥ 0.80 but ω is weakly constrained around-1,where ω describes the equation of state of the dark energy（pX = ωρX）.We conclude that OHD constrains the smoothness parameter more effectively than the data of SNe Ia and compact radio sources.

关键词： cosmology -- dark energy -- cosmological parameters

Singularity detection of the rabbit electrocardiogram:An evolutionary spectral method

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Progress in Natural science:Materials International 2009年第10期19卷 1317-1326页

作者： Xinyuan Liua,Dingwu He a,Liuqing Pei b,Suming Zhanga a School of Electronics Engineering and Computer science,peking university,beijing 100871,china b College of Information science and Engineering,beijing Normal university,beijing 100875,china [a]School of Electronics Engineering and Computer science Peking University Beijing 100871 China [b]College of Information science and Engineering Beijing Normal University Beijing 100875 China

The time-frequency characteristics of the spectral density of non-stationary signals(NSS) in the neighborhood of an instant time point can be determined using the evolutionary spectral *** experimental rabbit model involving ligation of the left anterior descending coronary artery to simulate the physiology of early phase myocardial ischemia(EPMI) has been previously ***,EPMI derived from left coronary artery stenosis is the main symptom of coronary heart diseases including acute myocardial ***,we propose a new algorithm for estimating the evolutionary spectral density functions,which is an effective approach to determine the instantaneous frequency spectra(IFS) of NSS under the uncertainty principle in the time-frequency *** localization singularity information in the data recorded from a living system could be detected by means of the ***(ECG) data recorded from experimental rabbits were analyzed with the new *** showed that the Q’s value of the evolutionary spectral quality number of the QRS-complex data was the characteristic parameter of ECG,and there was a matched connection between the time-frequency characteristics of QRS-complex data and the myocardial ischemia symptoms of the *** results provide valuable information regarding features of the EPMI for use in clinical diagnoses.

关键词： Non-stationary signals Electrocardiogram(ECG) Evolutionary spectrum Instantaneous frequency spectrum(IFS) Myocardial ischemia

The correlation of multi-angle thermal infrared data and the choice of optimal view angles

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science china Earth sciences 2004年第6期47卷 570-576页

作者： FAN Wenjie1 & XU Xiru1,2 1.Institute of Remote Sensing and GIS of peking university,beijing 100871,china 2.center of Remote Sensing and GIS of beijing Normal university,beijing 100875,china 1. Institute of Remote Sensing and GIS of peking university 100871 Beijing China 2. center of Remote Sensing and GIS of beijing Normal university 100875 Beijing China

Based on the matrix formula of thermal infrared radiant system, the components temperature can be retrieved by the inversive matrix. Around the stability problem of retrieved result, the research work we did was focused on (i) the correlation of (wk,j) which is the key to affect the retrieval accuracy, (ii) a general method which can help us find the number of retrievable parameters and evaluate the retrieval error before its performance, (iii) the choice of “optimal viewing angle group” based on the formula of absolute error propagation. The row winter wheat field was chosen as an example. The results can provide a theoretical basis for multi-angle thermal infrared remote sensing and components temperature retrieval.

关键词： components temperature retrieval, correlation, number of retrievable parameters, optimal viewing angle group.

Modeling the intracellular dynamics for Vif-APO mediated HIV-1 virus infection

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Chinese science Bulletin 2010年第22期55卷 2329-2340页

作者： WANG Yi1,2 & LAI LuHua1,3 1 center for Theoretical Biology, peking university, beijing 100871, china 2 School of Physics, peking university, beijing 100871, china 3 BNLMS, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, College of Chemistry and Molecular Engineering, peking university, beijing 100871, china center for Theoretical Biology Peking University Beijing 100871 China School of Physics Peking University Beijing 100871 China BNLMS State Key Laboratory for Structural Chemistry of Unstable and Stable Species College of Chemistry and Molecular Engineering Peking University Beijing 100871 China

The viral infectivity factor (Vif) was found to be essential for controlling HIV-1 virus infectivity. It targets cellular antiviral proteins in APOBEC family (APO) to trigger its fast degradation and inhibits APO packaging into nascent virion. In the present study, we propose a mathematical model to quantitatively study the intracellular dynamics of these typical virus-host interactions. Four sets of published experimental data were compared with simulation results to justify the model. Systematic parameter sensitivity and perturbation analysis showed that parameters related to APO are crucial to the infectivity of newly synthesized HIV-1 virus. Interestingly, we discovered that the synthesis rate of the viral structure protein Gag and the required number per nascent virion are optimized to achieve high virion production with minimal level of packaged APO, and large portion of model parameters are beneficial to virus only within a relatively small range. Furthermore, minor variations in several parameters related to viral protein Tat, the activator of viral RNA synthesis, were found to induce switch-like behaviors on both incorporated Vif and APO. These findings may provide new insights for understanding the high mutation rate of HIV-1 virus and its latency, as well as help identify key targets for therapeutic design.

关键词：病毒感染载脂蛋白 HIV 细胞内动力学抗病毒蛋白建模介导

Rat CC chemokine receptor 4 is the functional homologue of human CC chemokine receptor 4 and can interact with human CCL17 and CCL22

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Chinese science Bulletin 2010年第14期55卷 1388-1395页

作者： TIAN LinJie1,2, QI Hui1,2, XIE Yuan1,2, ZHANG YingMei1,2, ZHANG WenJuan1,2, SUN XiangYu1,2, WANG Ying1,2 & MA DaLong1,2 1 Laboratory of Medical Immunology, School of Basic Medical science, peking university health science center, beijing 100191, china 2 Human Disease Genomics center, peking university, beijing 100191, china Laboratory of Medical Immunology School of Basic Medical Science Peking University Health Science Center Beijing 100191 China Human Disease Genomics center Peking University Beijing 100191 China

Human CCL17/TARC (hCCL17) and CCL22/MDC (hCCL22) interact with their receptor CCR4, playing pivotal roles in various Th2 cell-dominant diseases. Rat Ccl17, Ccl22 and Ccr4 share 63.4%, 65.2% and 87.5% homology at the amino acid level, respectively, compared with their human homologues. Rat Ccl22 has been demonstrated to interact with rat Ccr4. However, it is not known whether rat Ccl17 is a functional ligand for rat Ccr4 and whether rat Ccr4 can interact with hCCL17 and hCCL22. In this study, we cloned rat Ccl17 and Ccr4 cDNA from rat thymus and expressed the recombinant rat Ccl17. The binding assay indicated rat Ccl17 could saturably bind rat Ccr4, and this binding could be competitively inhibited by unlabeled rat Cc17, hCCL17 or hCCL22. Both rat and human CCL17 or CCL22 could induce the chemotactic migration and calcium mobilization in rat Ccr4-transfected cells. They could also desensitize each other’s effect on chemotaxis and calcium mobilization. Furthermore, both rat Ccl17 and hCCL17 could induce significant receptor internalization in rat Ccr4-EGFP transfected cells. These results demonstrated the conserved CCL17/CCR4 interaction in rats and the further cross-species interaction of rat Ccr4 with hCCL17 and hCCL22. Likewise, they provided the molecular basis for the investigation of physiological and pharmacological roles of CCR4, its ligands, and their antagonists in rat disease models.

关键词：趋化因子受体同源性大鼠人类基因转染细胞绿色荧光蛋白相互作用疾病模型

Peroxisome proliferator-activated receptor γ ligands induce cell cycle arrest and apoptosis in human renal carcinoma cell lines

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Acta Pharmacologica Sinica 2005年第6期26卷 753-761页

作者： Feng-guang YANG~2, Zhi-wen ZHANG~3, Dian-qi XIN~2, Chang-jin SHI~2, Jie-ping WU~2, Ying-lu GUO~(2,4), You-fei GUAN~(3,4) ~2 department of Molecular Biology, Institute of Urology peking university First Hospital ~3 department of physiology and Pathophysiology, peking university health science center, beijing 100034, china department of Molecular Biology Institute of Urology Peking University First Hospital Beijing 100034 China department of physiology and Pathophysiology Peking University Health Science Center Beijing 100034 China

Aim: To study the effect of peroxisome proliferator-actived receptor y （PPARγ） ligands on cell proliferation and apoptosis in human renal carcinoma cell lines. Methods: The expression of PPARγ was investigated by reverse transcriptase polymerase chain reaction （RT-PCR）, Western blot and immunohistochemistry. The effect of thiazolidinedione （TZD） PPARγ ligands on growth of renal cell carcinoma （RCC） cells was measured by MTT assay and flow cytometric analysis. Cell death ELISA, Hoechst 33342 fluorescent staining and DNA ladder assay were used to observe the effects of PPARγ ligands on apoptosis. Regulatory proteins of cell cycle and apoptosis were detected by Western blot analysis. Results: PPARγ was expressed at much higher levels in renal tumors than in the normal kidney （2.16±0.85 vs 0.90±0.73; P50values of 7.08 μmol/L and 11.32 μmol/L for pioglitazone, and 5.71 μmol/L and 8.38 μmol/L for troglitazone in 786-0 and A498 cells, respectively. Cell cycle analysis showed a G0/G1arrest in human RCC cells following 24-h exposure to TZD. Analysis of cell cycle regulatory proteins revealed that TZD decreased the protein levels of proliferating cell nuclear antigen, pRb, cyclin D1, and Cdk4 but increased the levels of p21 and p27 in a time-dependent manner. Furthermore, high doses of TZD induced massive apoptosis in renal cancer cells, with increased Bax expression and decreased Bcl-2 expression. Conclusion: TZD PPARγligands showed potent inhibitory effect on proliferation, and could induce apoptosis in RCC cells. These results suggest that ligands for PPARγ have potential antitumor effects on renal carcinoma cells.

关键词： renal cell carcinoma peroxisome proliferator activated receptor γ cell cycle apoptosis cyclin cdk

PKG may modulate vessel tension via affecting Akt and PDE5

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PKG may modulate vessel tension via affecting Akt and PDE5

Role of cyclic GMP-dependent protein kinase in the development of tolerance to nitroglycerin of porcine coronary arteries

第八届海峡两岸心血管科学研讨会

作者： Dou Dou,Yuan-sheng Gao (department of physiology and Pathophysiology,peking university health science center,beijing,100191 china)

Objective PKG and Akt play important roles in the regulation of vessel *** present study was to determine whether or not PKG may affect vasodilation through *** Isolated porcine left anterior descending and left circumflex coronary arteries were dissected and cut into rings in ice - cold modified Krebs - Ringer bicarbonate *** activity was determined by Western blotting;isometric tension of the arteries were studied with organ chamber technique;the contents of cGMP were determined by ELISA *** 8-Br - cGMP(10 M) reduced Akt phosphorylation of porcine coronary arteries in a time - dependent *** of PI3K with LY294002(10 M) also attenuated the phosphorylation of Akt. LY294002 potentiated the relaxation of porcine coronary arteries to nitroglycerin and NO,but not to 8 - Br -cGMP, isoproterenol or Y27632(a specific Rho kinase inhibitor).The augmented relaxation to NO by LY294002 was eliminated by Akt - I or zaprinast(a specific inhibitor of PDE5),but not affected by ODQ(a specific inhibitor of sGC),nifedipine or milrinone(a specific inhibitor of PDE3 ).Inhibition of Akt caused similar effects as *** with LY294002 or Akt -I decreased the activity of PI3K and Akt but augmented the elevation of cGMP caused by *** cGMP elevation induced by LY294002 or Akt -I was also eliminated by *** The present study suggests that PKG may modulate vessel tension by affecting PDE5 through the inhibition of Akt.

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Role of cyclic GMP-dependent protein kinase in the developme...

Characteristics of TCRαβ + CD4 - CD8- thymocytes in fetal thymic organ culture

11th International Vascular Neuroeffector Mechanisms and Cardiovascular Pharmacology and Medicine Symposia, Shanghai-Suzhou 2006

作者： Dou Dou,Xiaoxu Zheng & Yuansheng Gao Dept.of physiology & Pathophysiology, peking university health science center, beijing, 100083, china

Objective: Cyclic GMP-dependent protein kinase (PKG) is an important mediator for the actions of nitrovasodilators such as nitroglycerin and nitric oxide. The present study was to determine the role of PKG in the development of tolerance to vasodilation induced by nitroglycerin. Methods: Isolated porcine left anterior defending and left circumflex coronary arteries were were dissected from the heart and cut into rings (outside diameter: -3.1 mm;length:-5mm) in

关键词： Role of cyclic GMP-dependent protein kinase in the development of tolerance to nitroglycerin of porcine coronary arteries ODQ

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Progress in Natural science:Materials International 2003年第6期 21-25页

作者： XIAO Shiyun , LI Yan , QIAN Xiaoping, WANG Yuedan and CHEN Weifeng(department of Immunology, peking university health science center, beijing 100083, china) department of Immunology Peking University Health Science Center Beijing 100083 China

TCRαβ + CD4-CD8- (TCR+ DN) thymocytes at different developmental periods, i.e. after either 9 or 18 days of culture in the fetal thymic organ culture (FTOC) system, were characterized in the properties of phenotype, proliferation, differentiation and apoptosis. The results showed that anti-CD3 mAb significantly promoted proliferation of TCRαβ+ DN cells generated after 18 days of culture in FTOC, whereas the cells generated after 9 days of culture responded to anti-CD3 mAb by proliferation weakly. IL-7 efficiently induced TCRαβ+ DN cells at day 9 of FTOC to differentiate into TCRαβ+ CD4+ /CD8 + SP cells without detectable transitional stage of TCRαβ+CD4 + CD8+(DP) cells. In contrast, fewerTCRαβ+ DN cells generated after 18 days of FTOC were induced to differentiate into SP cells. The thymic stromal cell line MTEC5 cells synergized with IL-7 to promote the differentiation of TCRαβ+ DN cells. In addition, TCRαβ+ DN cells were shown to be less susceptible to apoptosis compared with the other

关键词： FTOC TCRαβ+CD4-8- thymocyte.