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Production of human liver prolidase by Saccharomyces cerevisiae as host cells

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Acta Pharmacologica Sinica 2004年第6期25卷 92-98页

作者： Shu-hao WANG, Min LIU, Mu-gen CHI, Qing-ding WANG, Man-ji SUN2.institute of Pharmacologyand Toxicology, academy of Military {2. Science, beijing 100850, china institute of Pharmacology and Toxicology Academy of Military Medical Science Beijing 100850 Chin

AIM: To clone and express the recombinant human liver prolidase in yeast and explore the activities of both dipeptidaseand organophosphoric acid anhydrolase(OPAA). METHODS:The cDNAencodinghuman liver prolidase derived from healthy adult liver was cloned into the pYES2. an expression vector of S cerevisiae, and then trans- formed into S cerevisiae INVSc1 by electroporation. The transformant with the highest enzymatic activity was induced by galactose for expression. The optimal induction conditions (temperature, induction time, and the initial amount of inoculation cells) were estimated by orthogonal experimental design. The recombinant prolidase and OPAA activities were assayed by spectrocolorimetric methods. RESULTS: The recombinant enzyme catalyzed the hydrolysis of organophosphorous compound soman as well as the hydrolysis of dipeptide Gly-Pro. Under the optimal induction conditions (2. h, 2. oC, initial OD600=0.4), the maximum activities of prolidase and OPAA came to 2.6.5 and 578 μmol·min-1·g-1 protein in cell lysate supernatants, respectively. SDS-PAGE of the recombinant enzyme in disrupted cell supernatants showed a molecular weight of 56 kDa. Intensity scanning of the SDS-PAGE gel revealed that the enzyme accounted for 3.16 % of the total protein in the supernatant. One liter incubation medium produced 7 g of wet yeast cell containing 4.56 mg of the recombination protein. CONCLUSION: The recombinant human liver prolidase produced by yeast cell (S cerevisiae) exhibited both dipeptidase and OPAA activities.

关键词： prolidase liver human S Cerevisiae organophosphorous compounds

A PCA-based method for ancestral informative markers selection in structured populations

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Science china(Life sciences) 2009年第10期52卷 972-976页

作者： ZHANG Feng1,3, ZHANG Lei1,3 & DENG Hong-Wen1,2.3 1 Key Laboratory of Biomedical Information Engineering of Ministry of Education, institute of Molecular Genetics, School of Life Science and Technology, Xi’an Jiaotong University, Xi’an 710049, {2. 2.institute of Bioscience and biotechnology, School of Science, beijing Jiaotong University, beijing 100044, {2. 3 Departments of Orthopedic Surgery and Basic medical Science, School of medicine, University of Missouri-Kansas City, Kansas City, MO 64108, USA 1. Key Laboratory of Biomedical Information Engineering of Ministry of Education Institute of Molecular Genetics School of Life Science and Technology Xi’an Jiaotong University Xi’an 710049 China 3. Departments of Orthopedic Surgery and Basic medical Science School of Medicine University of Missouri-Kansas City Kansas City MO 64108 USA 2. institute of Bioscience and biotechnology School of Science Beijing Jiaotong University Beijing 100044 China

Identification of population structure can help trace population histories and identify disease genes. Structured association (SA) is a commonly used approach for population structure identification and association mapping. A major issue with SA is that its performance greatly depends on the informa-tiveness and the numbers of ancestral informative markers (AIMs). Present major AIM selection meth-ods mostly require prior individual ancestry information, which is usually not available or uncertain in practice. To address this potential weakness, we herein develop a novel approach for AIM selection based on principle component analysis (PCA), which does not require prior ancestry information of study subjects. Our simulation and real genetic data analysis results suggest that, with equivalent AIMs, PCA-based selected AIMs can significantly increase the accuracy of inferred individual ancestries compared with traditionally randomly selected AIMs. Our method can easily be applied to whole genome data to select a set of highly informative AIMs in population structure, which can then be used to identify potential population structure and correct possible statistical biases caused by population stratification.

关键词： population structure principle component analysis ancestral informative markers

Drug screening for influenza neuraminidase inhibitors

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Science china(Life sciences) 2005年第1期48卷 1-5页

作者： LIU Ailin, CAO Hongpeng & DU Guanhua institute of Materia Medica, Chinese academy of {2. sciences and Peking Union {2. College, beijing 100050, china institute of Medicinal biotechnology, Chinese academy of {2. sciences and Peking Union {2. College, beijing 100050, china institute of Materia Medica Chinese Academy of Medical Sciences and Peking Union Medical College Beijing 100050 Chin

Neuraminidase (NA) is one of the most important targets to screen the drugs of anti-influenza virus A and B. After virtual screening approaches were applied to a compound database which possesses more than 10000 compound structures, 160 compounds were selected for bioactivity assay, then a High Throughput Screening (HTS) model established for influenza virus NA inhibitors was applied to detect these compounds. Finally, three compounds among them displayed higher inhibitory activities, the range of their IC5o was from 0.1 μmol/L to 3 μmol/L. Their structural scaffolds are novel and different from those of NA inhibitors approved for influenza treatment, and will be useful for the design and research of new NA inhibitors. The result indicated that the combination of virtual screening with HTS was very significant to drug screening and drug discovery.

关键词： neuraminidase (NA), inhibitor, high throughput screening (HTS), influenza virus, virtual screening.

Protective effect of tubuloside B on TNFα-induced apoptosis in neuronal cells

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Acta Pharmacologica Sinica 2004年第10期 36-44页

作者： Min DENG, Jin-yuan ZHAO, Xiao-dong JU, Peng-fei TU, Yong JIANG, Zheng-bin LIResearch Center of Occupational medicine, Department of Orthopaedics, Peking University Third Hospital, beijing 100083, {2. Peking University Modem Research Center for Traditional Chinese medicine, beijing 100083, {2. institute of Materia Medica, Chinese academy of medical sciences, Peking Union medical College, beijing 100050, {2.

AIM: To investigate the neuroprotective effect of tubuloside B, one of the phenylethanoids isolated from the stems of Cistanche salsa, on tumor necrosis factor-alpha (TNFα)-induced apoptosis in SH-SY5Y neuronal cells. METHODS: Cell viability was analyzed using MTT assay. Apoptotic cells were detected using Hoechst33342.staining, and confirmed by DNA fragmentation and flow cytometric analysis. The activity of caspase-3 was measured with special assay kit. The concentration of free intracellular calcium was determined with the probe Indo-1 by spectrometer. The level of intracellular reactive oxygen species and the potential of mitochondrial membrane were determined by laser scanning confocal microscopy (LSCM) combined with fluorescence probe H2.CFDA or JC-1 respectively. RESULTS: SH-SY5Y cells treated with TNFa 100 μg/L for 36 h showed typical morphological changes of apoptosis. DNA ladder could be observed by agarose gel electrophoresis. The highest percentage of apoptotic cells accumulated to 37.5 %. F

关键词： tubuloside B apoptosis tumor necrosis factor SH-SY5Y cells mitochondria membrane potential reactive oxygen species caspase-3 calcium

Trace Elements in Health and Diseases

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Biomedical and Environmental sciences 1996年第2期9卷 130-136页

作者： XIA YI-MING (Department of Trace Element Nutrition, institute of Nutrition and Food Hygiene, 2. Nan Wei Road,Chinese academy of Preventive {2.,beijing 100050, china) Department of Trace Element Nutrition Chinese Academy of Preventive Medicine Beijing China.

Remarkable progress has occurred in many branches of biology and health sciences during the last few decades. Trace element (TE) research has definitely shared in this explosion of scientific knowledge. Due to the improvements in analytical technology, the discovery of TEs in organism was realized. The developments of TE research have been promoted by the demand of public health (e.g. deficiency or toxicity). The profound knowledge of nutritional importance of TEs has been achieved with application of advanced methods in biological, medical and chemical fields, etc. In this paper, a new definition of essentiality of TEs is introduced. According to this definition, onIy ten TEs (Fe, Zn, F, Cu, I, Se, Mn, Mo, Cr, Co) are considered to be essential to humans. The others need more evidence to prove their essentiality in humans. The recent progress on the biochemical and immunological functions of TEs and on the roles of TEs in brain development are briefly described. The TEs, mainly Se, I, Zn, Fe, are more closely related to public health. Also, emphases are laid on balancing all nutrients when new knowledge of essential TEs is applied in public health

关键词： Co WHO Trace Elements in Health and Diseases CVB UGA Chen TGA

Prevention and Treatment of Osteoporosis with Chinese Herbal medicines

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Chinese Herbal medicines 2012年第4期4卷 265-270页

作者： ZHAO Xiao-ling1,2.FENG Yu-xiong1,2.3,PENG Yong1,2.1.institute of Medicinal Plant Development,Chinese academy of {2. sciences and Peking Union {2. College,beijing 100193,china 2.Key Laboratory of Bioactive Substances and Resources Utilization of Chinese Herbal medicines,Ministry of Education,beijing 100193,china 3.College of Basic medicine,Guangxi University of Chinese medicine,Nanning 530001,china [a] institute of Medicinal Plant Development Chinese Academy of Medical Sciences and Peking Union Medical College Beijing 100193 China [b] Key Laboratory of Bioactive Substances and Resources Utilization of Chinese Herbal medicines Ministry of Education Beijing 100193 China [c] College of Basic medicine Guangxi University of Chinese Medicine Nanning 530001 China

In this paper,laboratory reports,medication rules,formulating principles,and research methods are summarized and analyzed,including single herb,compound herbs,and the problems in the prevention and treatment of osteoporosis(OP) within the past *** widely recognized efficacy,satisfying achievements have been achieved in preventing and treating OP with Chinese herbal medicines(CHM).However,due to the complex constituents,the pharmacological activities and mechanism of CHM are not clear yet,and there is no unified standard on the diagnosis and syndrome differentiation of OP and the efficacy evaluation of CHM in the ***,the research in the future should focus on the pharmacology and standardization of CHM in treating OP.

关键词： Chinese herbal medicines efficacy evaluation osteoporosis pharmacological activities prevention and treatment

Purification and characterization of a novel cholesterol-lowering protein from the seeds of Senna obtusifolia

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Science china(Life sciences) 2008年第11期51卷 1020-1024页

作者： LI ChuHua1, LI Mei2. CHANG WenRui2.& GUO BaoJiang1 1 College of Life sciences, South china Normal University, Guangdong Provincial Key Lab of {2. of Plant Development, Guang-zhou 510631, china 2.institute of Biophysics, Chinese academy of sciences, beijing 100101, china 1. College of Life sciences South China Normal University Guangdong Provincial Key Lab of Biotechnology of Plant Development Guangzhou 510631 China 2. institute of Biophysics Chinese Academy of Sciences Beijing 100101 China

"Juemingzi", a source of traditional Chinese herbal medicine, has been demonstrated to play a role in decreasing serum cholesterol concentration. In this study, a novel protein, which has shown an in-hibitory effect on cholesterol biosynthesis, was isolated from Senna obtusifolia L. seed by gel filtration and ion exchange chromatography. The novel protein’s molecular mass was 19.7 kD and its pI was 4.80. Both SDS-PAGE and isoelectric-focusing (IEF) revealed a single Coomassie brilliant blue stained band, indicating that the novel protein was a single peptide. The N-terminal amino acid sequence of the pro-tein was IPYISASFPLNIEFLPSE, which had no similarity with any other protein sequences in the NCBI protein database. Circular dichroism (CD) signals indicated that S. obtusifolia seed protein contained 12.5% α-helix, 55.6% β-sheet, and 31.9% random coil.

关键词： Senna obtusifolia L. seed novel protein purification biochemical properties cholesterol biosynthesis

Properties and applications of embryonic stem cells

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Chinese Science Bulletin 2000年第14期45卷 1258-1265页

作者： GUO Xiaoxia & HE Fuchu1. beijing institute of Radiation {2., beijing 100850, china 2. Department of Life Science, Shandong University, Ji’nan 2.0100, china Correspondence should he addressed to He Fuchu beijing institute of Radiation {2. Beijing China Department of Life Science Shandong University Ji’nan China

Mouse embryonic stem (ES) cells are pluripotent cells derived from the early embryo and can be propagated stably in undifferentiated state in vitro. They retain the ability to differentiate into all cell types found in the embryonic and adult body in vivo, and can be induced to differentiate into many cell types under appropriate culture conditions in vitro. Using these properties, people have set up various differentiated systems of many cell types and tissues in vitro. Through analysis of these systems, one can identify novel bioactive factors and reveal mechanisms of cell differentiation and organogenesis. ES cell-derived differentiated cells can also be applied to cell transplantation therapy. In addition, we summarized the features and potential applications of human ES cells.

关键词： embryonic stem cell differentiation in vitro cell transplantation therapy gene targeting.

Comparative study on the effect of integrin αvβ3 on secretion of matrix metalloproteinases in human normal and carcinoma trophoblasts

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Progress in Natural Science:Materials International 2005年第11期15卷 982-987页

作者： BAI Suxia, FU Yayuan, KONG Gang and WANG Yanling (State Key Laboratory of Reproductive Biology, institute of Zoology, Chinese academy of {2., beijing 100080, china The Second Hospital of Chinese medicine College, Shenyang 110003, china) State Key Laboratory of Reproductive Biology Institute of Zoology Chinese Academy of Sciences Beijing 100080 China. The Second Hospital of Chinese medicine College Shenyang 110003 China

The invasion of cytotrophoblast cells into the maternal endometrium during embryonic implantation is very similar to the metastasis of carcinoma cells. However, the significant difference is that the former is a highly controlled process. In this report, the effects of integnn αvβ3 on the secretion of matrix metalloproteinase (MMP) were compared between normal cytotrophoblast cells and chorio-carcinoma cells by RT-PCR, gelatin zymography and immunocytochemistry. The results reveal that both normal cytotrophobiast cells and choriocarcinoma cells can express integrin αvβ3. The secretion of MMPs in normal cytotrophoblast cells is up-regulated by anti-αvβ3 antibody, whereas, decreased in choriocarcmoma cells. It was suggested that αvβ3 can modulate the expression of MMPs in trophoblasts, and this action is carried out through distinct mechanisms in normal and carcinoma cytotrophoblast cells.

关键词： cytotrophoblast cells choriocarcinoma cells integrfn αvβ3 matrix metalloproteinase.