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Screening and docking studies of natural phenolic inhibitors of carbonic anhydrase Ⅱ

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Science China Chemistry 2009年第3期52卷 332-337页

作者： HUANG HuoQiang1. 2, PAN XuLin1. JI ChangJiu1. 2, ZENG GuangZhi1. JIANG LiHua1. FU Xiang1. LIU JiKai1. HAO XiaoJiang1. ZHANG YingJun1.& TAN NingHua1.1.State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650204, China 2 graduate {1. of the Chinese Academy of Sciences, Beijing 1.0049, China 1. State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of Botany Chinese Academy of Sciences Kunming 650204 China 2. graduate {1. of the Chinese Academy of Sciences Beijing 100049 China

Carbonic anhydrase Ⅱ (CAⅡ) is an important enzyme complex with Zn2+,which is involved in many physiological and pathological processes, such as calcification, glaucoma and tumorigenicity. In order to search for novel inhibitors of CAⅡ, inhibition assay of carbonic anhydrase Ⅱ was performed, by which seven natural phenolic compounds, including four phenolics (grifolin, 4-O-methyl-grifolic acid, grifolic acid, and isovanillic acid) and three flavones (eriodictyol, quercetin and puerin A), showed in-hibitory activities against CAⅡ with IC50s in the range of 6.37-71.73 μmol/L. Grifolic acid is the most active one with IC50 of 6.37 μmol/L. These seven phenolic compounds were proved to be novel natural carbonic anhydrase Ⅱ inhibitors, which were obtained in flexible docking study with GOLD 3.0 soft-ware. Results indicated that the aliphatic chain and polar groups of hydroxyl and carboxyl are impor-tant to their inhibitory activities, providing a new insight into study on CA Ⅱ potent inhibitors.

关键词： carbonic anhydraseⅡ natural inhibitors screening docking

CH_4 uptake flux of Leymus chinensis steppe during rapid growth season in Inner Mongolia,China

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Science China Earth Sciences 2010年第7期53卷 977-983页

作者： GENG YuanBo1. LUO GuangQiang1.2 & YUAN GuoFu1.1.Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 1.01.1. China 2 graduate {1. of Chinese Academy of Sciences, Beijing 1.0049, China 1. Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China

The influence of near ground atmosphere CH4 concentration, soil water content, soil Eh, plants, soil temperature, and pH on CH4 uptake flux of Leymus chinensis steppe during rapid growth season was studied using field in-situ measurement in Xilin River basin of Inner Mongolia, China. The results showed that CH4 uptake flux was positively correlated with near ground atmosphere CH4 concentration and soil Eh but negatively correlated with soil water content. Precipitation may decrease the CH4 flux by increasing the soil water content. The average fluxes of three treatments during the observation period were 1.52 (natural conditions, 1.51.(aboveground plants were excluded), and 2.00 mg m?2 d?1.(all plants were removed), respectively. The difference between the CH4 flux of natural condition treatment and that of removing aboveground plants treatment is small, whereas the flux of removing all plants treatment is larger than the other two treatments. This means that the contribution of aboveground plants to CH4 uptake flux is smaller than that of roots or roots-removing process. CH4 uptake flux is not sensitive to soil temperature and the narrow-ranged soil pH (6.36–7.86). The Leymus chinensis steppe acts as a sink for CH4, and thus more studies should be focused on its affecting factors and related mechanisms.

关键词： CH4 uptake flux Leymus chinensis steppe affecting factors static opaque chamber/gas chromatography method

The influence of moderate ENSO on summer rainfall in eastern China and its comparison with strong ENSO

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Chinese Science Bulletin 2008年第5期53卷 791-800页

作者： XUE Feng1.& LIU ChangZheng1.2 1.Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 1.0029, China 2 graduate {1. of Chinese Academy of Sciences, Beijing 1.0049, China Chinese Acad Sci Inst Atmospher Phys Beijing 100029 Peoples R China.

The 6 major ENSO events since 1.79 are classified into the strong and moderate ENSO based on in-tensity. The composite analysis is performed to reveal the influence of ENSO on East Asian summer monsoon (EASM) and summer rainfall in eastern China. It is shown that the influence is changed with the seasonal cycle in summer, with a weaker influence in June and a stronger influence in August, in-dicating a long lagged effect of ENSO on EASM. Besides, the circulation and rainfall anomalies caused by the strong ENSO are also stronger with an earlier starting time, while the influence of the moderate ENSO is evident in August. The composite summer rainfall in eastern China for the moderate ENSO exhibits a northern rainfall pattern, which is totally different from the classical ENSO-type rainfall pat-tern. Based on the composite analysis, two moderate ENSO years with a similar intensity (i.e., 1.95 and 2003) are compared. The result shows that, the response of EASM to the moderate ENSO during June and July is, to a certain degree, modulated by the circulation systems in mid-high latitudes of Eurasia and in the Southern Hemisphere, thereby inducing a different rainfall distribution in eastern China. In comparison with the strong ENSO in 1.83, it is further revealed that, the strong ENSO plays a dominant role in summer rainfall anomalies in eastern China as well as in controlling the influence of the other factors on EASM. The strong ENSO is therefore different with the moderate ENSO.

关键词：中国东部海洋气象学厄尔尼诺现象东亚季风降雨

Pre-irradiation with low-dose ^(1.)C^(6+) beam significantly enhances the efficacy of AdCMV-p53 gene therapy in human non-small lung cancer

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Science China(Physics,Mechanics & Astronomy) 2007年第2期50卷 221-230页

作者： LIU Bing1.2,ZHANG Hong1.LI WenJian1.LI Qiang1.ZHOU GuangMing1.XIE Yi1.2,HAO JiFang1.MIN FengLing1.2,ZHOU QingMing1.2 & DUAN Xin1.21.Institute of Modern Physics,Chinese Academy of Sciences,Lanzhou 730000,China 2 graduate {1. of Chinese Academy of Sciences,Beijing 1.0039,China Institute of Modern Physics Chinese Academy of Sciences Lanzhou 730000China

The combination of ionizing radiation and gene therapy has been investigated. However, there are very few reports about the combination of heavy-ion irradiation and gene therapy. To determine if the pre-exposure to low-dose heavy ion beam enhances the suppression of AdCMV-p53 on non-small lung cancer (NSLC), the cells pre-irradiated or non-irradiated were infected with 20, 40 MOI of AdCMV-p53. Survival fraction and the relative biology effect (RBE) were determined by clonogenic assay. The results showed that the proportions of p53 positive cells in 1.C6+ beam induced AdCMV-p53 infected cells were more than 90%, which were signifi-cantly more than those in γ-ray induced AdCMV-p53 infected cells. The pre-exposure to low-dose 1.C6+ beam significantly prevented the G0/G1.arrest and activated G2/M checkpoints. The pre-exposure to 1.C6+ beam significantly improved cell to apoptosis. RBEs for the 1.C6+ + AdCMV-p53 infection groups were 30%-60%, 20%-1.0% and 30%-70% more than those for the 1.C6+-irradiated only, AdCMV-p53 infected only, and γ-irradiation induced AdCMVp53 infected groups, respectively. The data suggested that the pre-exposure to low-dose 1.C6+ beam significantly promotes exogenous p53 expression in NSLC, and the suppression of AdCMV-p53 gene therapy on NSLC.

关键词： heavy-ion beam gene therapy p53 non-small lung cancer adenoviral vector low dose

Variation properties of ionospheric eclipse factor and ionospheric influence factor

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Progress in Natural Science:Materials International 2005年第6期15卷 573-576页

作者： ZHAO Chunmei 1.2 *, YUAN Yunbin1. OU Jikun1.and CHEN Jinping3(1. Institute of Geodesy and Geophysics, Chinese Academy of Sciences, Wuhan 430077, China 2. graduate School of Chinese Academy of Sciences, Beijing 1.0039, China 3. Department of Precision Instrument and Mechanology, Tsinghua {1., Beijing 1.0084, China) Institute of Geodesy and Geophysics Chinese Academy of Sciences Wuhan 430077 China graduate School of Chinese Academy of Sciences Beijing 100039 China Department of Precision Instrument and Mechanology Tsinghua University Beijing 100084 China

The concepts and calculation methods of ionospheric eclipse factor (IEF) and ionospheric influence factor (IFF) are further illustrated. The temporal and spacial variation properties of IEF and IFF are studied, which shows that the properties are influenced by the geographic position and season. The possibility of improving the precision of using GPS data to determine ionospheric delay based on the above variation properties is also analysed.

关键词： GPS ionospheric eclipse factor ionospheric influence factor

Terrestrial transect study on driving mechanism of vegetation changes

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Science China Earth Sciences 2008年第7期51卷 984-991页

作者： ZHANG YuJin1.2 & ZHOU GuangSheng1.1.State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing 1.0093, China 2 graduate {1. of Chinese Academy of Sciences, Beijing 1.0049, China 1. State Key Laboratory of Vegetation and Environmental Change Institute of Botany Chinese Academy of Sciences Beijing 100093 China 2. graduate {1. of Chinese Academy of Sciences Beijing 100049 China

In terms of Chinese climate-vegetation model based on the classification of plant functional types, to- gether with climatic data from 1.51.to 1.80 and two future climatic scenarios (SRES-A2 and SRES-B2) in China from the highest and the lowest emission scenarios of greenhouse gases, the distribution patterns of vegetation types and their changes along the Northeast China Transect (NECT) and the North-South Transect of Eastern China (NSTEC) were simulated in order to understand the driving mechanisms of vegetation changes under climatic change. The results indicated that the vegetation distribution patterns would change significantly under future climate, and the major factors driving the vegetation changes were water and heat. However, the responses of various vegetation types to the changes in water and heat factors were obviously different. The vegetation changes were more sensi- tive to heat factors than to water factors. Thus, in the future climate warming will significantly affect vegetation distribution patterns.

关键词： driving mechanism vegetation terrestrial transect climatic change plant functional types

Genesis of ^(230)Th excess in basalts from mid-ocean ridges and ocean islands:Constraints from the global U-series isotope database and major and rare earth element geochemistry

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Science China Earth Sciences 2010年第10期53卷 1486-1494页

作者： ZHANG GuoLiang1.2 & ZENG ZhiGang1.1.Key Laboratory of Marine Geology and Environment,Institute of Oceanology,Chinese Academy of Sciences,Qingdao 266071.China 2 graduate {1. of Chinese Academy of Sciences,Beijing 1.0049,China 1. Key Laboratory of Marine Geology and Environment Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China

Based on 230Th-238U disequilibrium and major element data from mid-ocean ridge basalts(MORBs) and ocean island basalts(OIBs),this study calculates mantle melting parameters,and thereby investigates the origin of 230Th excess.(230Th/238U) in global MORBs shows a positive correlation with Fe8,Po,Na8,and Fmelt(Fe8 and Na8 are FeO and Na2O contents respectively after correction for crustal fractionation relative to MgO = 8 wt%,Po=pressure of initial melting and Fmelt=degree of melt),while 230Th excess in OIBs has no obvious correlation with either initial mantle melting depth or the average degree of mantle ***,compared with the MORBs,higher(230Th/238U) in OIBs actually corresponds to a lower melting *** suggests that the 230Th excess in MORBs is controlled by mantle melting conditions,while the 230Th excess in OIBs is more likely related to the deep garnet *** vast majority of calculated initial melting pressures of MORBs with excess 230Th are between 1.0 and 2.5 GPa,which is consistent with the conclusion from experiments in recent years that DU>DTh for Al-clinopyroxene at pressures of >1.0 *** initial melting pressure of OIBs is 2.2-3.5 GPa(around the spinel-garnet transition zone),with their low excess 226Ra compared to MORBs also suggesting a deeper mantle ***,excess 230Th in MORBs and OIBs may be formed respectively in the spinel and garnet stability *** addition,there is no obvious correlation of K2O/TiO2 with(230Th/238U) and initial melting pressure(Po) of MORBs,so it is proposed that the melting depth producing excess 230Th does not tap the spinel-garnet transition *** and MORBs in both(230Th/238U) vs.K2O/TiO2 and(230Th/238U) *** plots fall in two distinct areas,indicating that the mineral phases which dominate their excess 230Th are ***/Yb-Ce curves of fast and slow ridge MORBs are similar,while,in comparison,the Ce/Yb-Ce curve for OIBs shows more influence from *** mechanism

关键词： excess 230Th clinopyroxene garnet spinel-lherzolite mid-ocean ridge ocean island

Bioreducible crosslinked low molecular weight branched PEI-PBLG as an efficient gene carrier

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Science China Chemistry 2010年第12期53卷 2490-2496页

作者： GUO ZhaoPei 1.TIAN HuaYu 1.XIA JiaLiang 1.2,CHEN Jie 1.LIN Lin 1.& CHEN XueSi 1.1.Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied Chemistry,Chinese Academy of Sciences,Changchun 1.0022,China 2 graduate {1. of Chinese Academy of Sciences,Beijing 1.0049,China 1. Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China

Low molecular weight polyethylenimine-poly(gamma-benzyl L-glutamate) (PEI-PBLG) was crosslinked by N,N'-cystaminebisacrylamide (CBA) to get the polymer named as CBA-PEI-PBLG (CPP).CPP not only inherits PEI-PBLG's amphiphilic advantages,but also possesses reducible *** can complex with DNA to form ***/DNA complex particles were characterized by particle size and zeta potential *** result showed that the complex particles have suitable size and surface charges for gene *** gel retardation assay also prove CBA-PEI-PBLG has proper condensing ability for *** has good reducible property,and also has good biocompatibility because of introducing PBLG *** cytotoxicity of CPP was evaluated using MTT assay,and the results showed CPP has lower cytotoxicity compared with PEI 25 *** transfection properties were characterized in different cells by using plasmid DNA as a *** showed higher transfection efficiencies and lower cytotoxicity in HeLa *** was attributed to bioreducible and biocompatibility properties of the *** results suggested that CPP is a promising low-toxic,highly effective non-viral gene carrier.

关键词： gene carrier transfection cytotoxicity crosslinked

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 {1. School,Shenzhen 51.055,China 2Institute of Remote Sensing and Geographical Information Systems,Peking university,Beijing 1.0871.China 3College of Urban and Environmental Science,Peking university,Beijing 1.0871.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