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Role of inositol 1,4,5-trisphosphate receptors in α1-adrenergic receptorinduced cardiomyocyte hypertrophy

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Acta Pharmacologica Sinica 2006年第7期27卷 895-900页

作者： Da-li LUO~(2,3.5) Jian GAO~2 Xiao-mei LAN~3.Gang WANG~4 Sheng WEI~4 Rui-ping XIAO~4 Qi-de HAN~3. Department of Pharmacology,School of Chemical Biology & Pharmaceutical sciences,Capital university of Medical sciences,{3. 100069,china 3.Institute of Cardiovascular science at Health science center,peking university {3. 100083.china 4 Institute of Molecular Medicine and College of Life science,peking university,{3. 100871,china Department of Pharmacology School of Chemical Biology & Pharmaceutical Sciences Capital University of Medical Sciences Beijing 100069 China Institute of Cardiovascular science at Health science center Peking University Beijing 100083 China Institute of Molecular Medicine and College of Life science Peking University Beijing 100871 China

Aim:Intracellular Ca2+plays pivotal roles in diverse cellular functions,includinggene transcription that underlies cardiac remodeling during stress ***,the role of inositol 1,4,5-trisphosphate receptors（IP3.s）in the media-tion of cardiac intracellular Ca2+and hypertrophic growth remains *** with neonatal rat ventricular myocytes suggests that activation of IP3.smay be linked to α1adrenergic receptor（α1AR）increased stereotyped Ca2+sparkoccurrence and global Ca2+***,we hypothesized that Ca2+releasethrough IP3.s was necessary for α1AR-stimulated cardiac ***:We used myoinositol 1,4,5-trisphosphate hexakis（butyryloxymethyl）ester（IP3.M）,a membrane-permeant ester of IP3.to activate IP3.s directly,and Fluo 4/AM tomeasure intracellular Ca2+***:IP3.M(10μmol·L-1)mimicked theeffects of phenylephrine,a selective agonist of α1AR,in increments in local Ca2+spark release（especially in the perinuclear area）and global Ca2+*** importantly,IP3. inhibitors,2-aminoethoxydiphenyl borateand Xestospongin C,abolished the IP3.M-induced Ca2+responses,and signifi-cantly suppressed α1AR-induced cardiomyocyte hypertrophy assayed by cellsize,[3.]leucine incorporation and atrial natriuretic factor gene expression,dur-ing sustained（48 h）phenylephrine ***:These results,therefore,provide cellular mechanisms that link IP3. signaling to α1AR-stimulatedgene expression and cardiomyocyte hypertrophy.

关键词： inositol 1,4,5-trisphosphate receptors Ca2+sparks α1 adrenergic stimulation cardiac hypertrophy

A　Diference　Scheme　with　Anti－difusion　Terms　to　Improve　the　Computation　of　Contact　Discontinuities　and　the　Study　of　Weak　Discontinuities　in　Compresible　Flow

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Communications in Nonlinear science and Numerical Simulation 1996年第4期1卷 42-51页

作者： Chunguang XU (College of Mathematical science ,peking university,{3.) College of Mathematical science peking university beijing 100871 USA

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Ａｂｓｔｒａｃｔ：ＴｈｅｉｎｖｅｓｔｉｇａｔｉｏｎｏｆＭａｃｈｒｅｆｌｅｃｔｉｏｎｆｏｒｍｅｄａｆｔｅｒｔｈｅｉｍｐｉｎｇｅｍｅｎｔｏｆａｗｅａｋｐｌａｎｅｓｈｏｃｋｗａｖｅｏｎａｗｅｄｇｅ，ｗｉｔｈｓｈｏｃｋＭａｃｈｎｕｍｂｅｒＭｓｎｅａｒ１，ｉｓｓｔｉｌａｎｏｐｅｎｐｒｏｂｌｅｍ［１２］．Ｉｔ＇ｓｄｉｆｉｃｕｌｔｆｏｒｓｈｏｃｋｔｕｂｅｅｘｐｅｒｉｍｅｎｔｓｗｉｔｈｉｎｔｅｒｆｅｒｏｍｅｔｅｒｔｏｄｅｔｅｃｔｃｏｎｔａｃｔｄｉｓｃｏｎ－ｔｉｎｕｉｔｉｅｓ，ｉｆｉｔｉｓｔｏｏｗｅａｋ；ａｌｓｏｄｉｆｉｃｕｌｔｔｏｃａｔｃｈｗｉｔｈｄｕｅａｃｃｕｒａｃｙｔｈｅｔｒａｎｓｉｔｉｏｎｃｏｎｄｉｔｉｏｎｂｅｔｗｅｅｎＭａｃｈｒｅｆｌｅｃｔｉｏｎａｎｄｒｅｇｕｌａｒｒｅｆｌｅｃｔｉｏｎ．Ｔｈｅｉｎｔｅｒｅｓｔｔｏｔｈｉｓｐｈｅｎｏｍｅｎｏｎｉｓｃｏｎｔｉｎ－ｕｉｎｇ，ｅｓｐｅｃｉａｌｙｆｏｒｗｅａｋｓｈｏｃｋｓ，ｂｅｃａｕｓｅｔｈｅｒｅｗａｓｓｙｓｔｅｍａｔｉｃｄｉｓｃｒｅｐａｎｃｙｂｅｔｗｅｅｎｓｉｍ－ｐｌｉｆｉｅｄｔｈｒｅｅｓｈｏｃｋｔｈｅｏｒｙｏｆｖｏｎＮｅｕｍａｎｎ［８］ａｎｄｓｈｏｃｋｔｕｂｅｒｅｓｕｌｔ

关键词： weak reflection Mach reflection anti-diffusion

Petrogenesis of Songshugou dunite body in the Qinling orogenic belt, Central china: Constraints from geochemistry and melt inclusions

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science china Earth sciences 2005年第8期48卷 1146-1157页

作者： SU Li1,2, SONG Shuguang3.& ZHOU Dingwu1 1. Key Laboratory of Continental Dynamics of the Ministry of Education, Department of Geology, Northwestern university, Xi’an 710069, china 2. The Geological Lab center, china university of Geosciences (beijing), beijing 100083. china 3. Key Laboratory of Orogenic Belts of the Ministry of Education, Department of Geology, peking university, beijing 100871, china 1. Key Laboratory of Continental Dynamics of the Ministry of Education Department of Geology Northwestern University 710069 Xi’an China 2. The Geological Lab center China University of Geosciences 100083 (Beijing)Beijing China 3. Key Laboratory of Orogenic Belts of the Ministry of Education Department of Geology Peking University 100871 Beijing China

The Songshugou dunite body, which occupies an area of about 20 km2, is the largest ultramafic massif in the eastern Qinling orogenic belt, Central china. The major compo-nent of this body is dunitic rocks including mylonitic dunite and coarse-grained dunite; they oc-cupy about 95 vol% of the total body. Petrography, mineral composition, major and trace ele-ments and primitive melt inclusions have been investigated in this paper; all revealed that this dunite body is the product of melt-rock interaction by porous percolation flow. In comparison with dunite sills or veins in harzburgite from the basal part of Oman ophiolite, this dunite body is characterized by lower contents of Al2O3. CaO and HREE but higher content of highly incom-patible elements and Zr and Hf. The LREE enriched patterns and primitive mantle normalized spidergrams of trace elements are also different from the Oman dunite. Combining with melt in-clusions observed in olivines, we conclude that this dunite body is the product of large- scale porous percolation flow of high-MgO melts within depleted mantle peridotites. The high-MgO magma, in essence, was most probably produced at the hot head of an upwelling mantle plume. The occurrence of the Songshugou dunite body is closely associated with the activity of mantle super-plume in Neo-Proterozoic era in the Yangtze Craton.

关键词： Songshugou dunite body, geochemistry, melt inclusion, mantle plume, Qinling orogenic belt.

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,{3. 2 School of Physics, peking university, beijing 100871,{3. 3.BNLMS, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, College of Chemistry and Molecular Engineering, peking university, beijing 100871,{3. 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

AutoProc: An automatic proactive replication scheme for P2P storage

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science china(information sciences) 2011年第6期54卷 1151-1160页

作者： YANG Zhi & DAI YaFei Computer science Department, peking university, beijing 100871,{3. 1. Computer science Department Peking University Beijing 100871 China

Due to the prevalence of peer departures, P2P storage systems need to constantly generate replicas for high durability. However, few existing systems are able to select the right replication rate that balances replication cost and durability, e.g., minimizing replication cost without threatening the durability target. In this paper, we propose a method called AutoProc to automate the replication process in P2P storage systems. AutoProc employs two key techniques to enable cost-effective replication: correctly adapting replication rate with a reliability model, and replicating objects at the right order with a reliability indicator. Extensive simulations based on the real system failure trace show that AutoProc achieves the near-optimal performance.

关键词： P2P storage churn durability fault tolerance proactive replication resource usage

A stochastic method for convective storm identification,tracking and nowcasting

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Progress in Natural science:Materials International 2008年第12期18卷 1557-1563页

作者： Lei Han~(a,b) Shengxue Fu~a Guang Yang~c Hongqing Wang~b Yongguang Zheng~d Yingjing Lin~b a College of information science and Engineering.Ocean university of{3.,Qingdao 266101,china b Department of Atmospheric science,peking university,beijing 100871,china c Department of Probability and Statistics,peking university,beijing 100871,china d National Meteorological center,beijing 100081,china [a]College of information science and Engineering Ocean University of China Qingdao 266101 China [b]Department of Atmospheric science Peking University Beijing 100871 China [c]Department of Probability and Statistics Peking University Beijing 100871 China [d]National Meteorological center Beijing 100081 China

The convective storm identification,tracking and nowcasting method is one of the important nowcasting methodologies against severe convective *** severe convective cases,such as storm shape or rapid velocity changes,existing methods are apt to provide unsatisfied storm identification,tracking and nowcasting *** overcome these difficulties,this paper proposes a novel approach to identify,track and short-term forecast (nowcast) of convective storms.A mathematical morphology-based storm identification method is adopted which can identify storm cells accurately in a cluster of *** for the difficult tracking problem,sequential Monte Carlo (SMC) method is utilized to simplify the tracking *** is not only inherently suitable for handling complicated splits and mergers, but also capable of handling the case of storm-missing *** order to provide more accurate forecast of a storm position,this method takes the advantages of the cross-correlation *** qualitative and quantitative evaluations show the efficiency and robustness of the proposed approach.

关键词： Convective storm Doppler radar Nowcasting

Positioning localities from spatial assertions based on Voronoi neighboring

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science china(Technological sciences) 2010年第S1期53卷 143-149页

作者： GONG YongXi 1,2,3.LI GuiCai 1,LIU Yu 2 & YANG Jian 1 1 Shenzhen Key Lab of Recycling Economy,peking university Shenzhen Graduate School,Shenzhen 518055,china 2Institute of Remote Sensing and Geographical {3. Systems,peking university,beijing 100871,china 3.ollege of Urban and Environmental science,peking university,beijing 100871,china peking Univ Shenzhen Grad Sch Shenzhen Key Lab Recycling Econ Shenzhen 518055 Peoples R China peking Univ Inst Remote Sensing & Geog Informat Syst Beijing 100871 Peoples R China peking Univ Coll Urban & Environm Sci Beijing 100871 Peoples R China

With the rapid development of Internet,much spatial information contained in non-structured or semi-structured documents is available on the World Wide *** such documents,localities are always textually described using spatial relationships and named places,instead of numerical ***,extracting positional information from locality descriptions is an important *** this paper,we bridge two aspects of locality descriptions,namely generating locality descriptions and positioning localities,and provide a method to compute probability density according to the selection probability of a reference object to describe the position of the target *** operation on uncertainty field is used to deal with locality description involving multiple reference *** metrics are introduced to measure the results of positioning *** choose the mixed selection probability function based on Euclidean distance and Voronoi stolen-area to compute probability density ***,we use three cases to demonstrate the proposed methods.

关键词： geographic information science positioning locality Voronoi neighboring probability density function

Framework and development of digital china

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science china(Technological sciences) 2008年第S1期51卷 1-5页

作者： WU Lun & TONG QingXi Institute of Remote Sensing and Geographical information Systems,peking university,{3. 100871,china 1. Institute of Remote Sensing and Geographical information Systems Peking University Beijing 100871 China

Digital china (DC) has recently drawn much attention. It is a strategic project for china in response to the challenge of sustainable development of population,re-source,and environment. Intending to establish the national information infra-structure (NⅡ),the DC project forms a solid foundation for Chinese informatization. In such an NⅡ,multi-sourced spatial data are integrated. They focus on various themes and have different space and time features. Based on the NⅡ,numerous applications and services can be developed so that spatial information will benefit everyone. Since lots of organizations,such as governments,universities,and en-terprises,are involved in the implementation of DC,the DC project will significantly prompt the relevant scientific research as well as economic progress in china.

关键词： Digital Earth Digital china spatial information sciences and technology

Posttranslational modulation on the biological activities of molecular chaperones

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science china(Life sciences) 2009年第6期52卷 515-520页

作者： CHANG ZengYi center for Protein science,School of Life science,National Laboratory of Protein Engineering and Plant Genetic Engineering,{3. university,beijing 100871,china center for Protein science School of Life Science National Laboratory of Protein Engineering and Plant Genetic Engineering Peking University Beijing 100871 China

Molecular chaperones are a family of proteins that were first noticed to exist about 45 years ago from their increased transcription under heat shock *** a result,the regulation of their encoding genes has been subject to extensive *** studies revealed that the biological activities of molecular chaperones can also be effectively modulated at the protein *** ways of modulation so far elucidated include allosteric effect,covalent modification,protein-protein interaction,and con-formational alteration induced by such macro-environmental conditions as temperature and *** latter aspects were reviewed *** here is the importance of such immediate structural alterations that lead to an immediate activity increase,providing the immediate protection needed for the cells to survive the stress conditions.

关键词： molecular chaperone activity modulation sHsp Hsp60 Hsp70 Hsp90 Hsp100 HdeA DegP