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Influence of viscosity on the phase transformation of amorphous calcium carbonate in fluids:An understanding of the medium effect in biomimetic mineralization

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Science china Chemistry 2010年第10期53卷 2208-2214页

作者： XIE YiDong, XU XuRong & TANG RuiKang center for Biomaterials and Biopathways and Department of Chemistry, Zhejiang university, Hangzhou 310027, china 1. center for Biomaterials and Biopathways and Department of Chemistry Zhejiang University Hangzhou 310027 China

biological mineral generation via an amorphous precursor is a topic of great current interest. Various factors such as the temperature, solution composition and presence of organic molecules can influence this important inorganic process. Here we demonstrate that this mineral transformation can actually readily be regulated by solution viscosity, a fundamental but often overlooked property. In our experiment, amorphous calcium carbonate (ACC), a key model compound in biomimetic mineralization studies, is synthesized and dispersed into inert dispersants with different viscosities and the crystallization process is examined by using FT-IR spectroscopy and XRD. It is found that the inhibition of the transformation of ACC becomes more significant with increasing fluid viscosity. This phenomenon can be explained by the differences in ion diffusion in different media. Furthermore, the resulting crystals always have different morphologies and size distributions although they all have the calcite structure. This study implies that the importance of the fluid medium cannot be ignored in building a complete understanding of biological control of biomimetic crystallizations.

关键词： mineralization amorphous calcium carbonate transformation viscosity

A novel tetrahydrofuranyl fatty acid from a new microbial isolate,Pestalotia *** 69032

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A novel tetrahydrofuranyl fatty acid from a new microbial is...

Cloning and sequencing of nifBHDKENX genes of Paenibacillus massiliensis T7 and its nif promoter analysis

中国化学会第9届天然有机化学学术会议

作者： Xueqiong Yang~1,Yabin Yang~1,Lixing Zhao~2,Hao Zhou~1,Lihua Xu~2,Zhongtao Ding~(*1) 1.Key Laboratory of Medicinal Chemistry for Natural Resource,Ministry of Education,School of Chemical Science and Technology,yunnan university,kunming 650091,yunnan,china. 2.yunnan Institute of Microbiology,yunnan university,kunming 650091,yunnan,china.

＜正＞Hydroxy fatty acids（FA） have great potential for use as bioactive agents and raw materials for the synthesis of specialty *** metabolize and produce a broad range of organic compounds,many of them exhibit biological activities,Recently the production of hydroxy FA through bioconversion by microorganisms has been a major focus of *** pulp has been shown in some cases to be a good component of growth media,for example fostering elevated production of FA by the fungus Rhizopus oryzae

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Science china(Life Sciences) 2006年第2期49卷 115-122页

作者： ZHAO Hongxin1,2,3, XIE Baoen2 & CHEN Sanfeng1,2 1. State Key Laboratory for Agrobiotechnology and biological School, china Agricultural university, Beijing 100094. china 2. Key Laboratory for Agro-Microbial Resource and Application of Agriculture Ministry, china Agricultural university, Beijing 100094. china 3. Chemical and biological School, ShenYang Normal university, Shenyang 110034. china 1. State Key Laboratory for Agrobiotechnology and biological School China Agricultural University Beijing 100094 China 2. Key Laboratory for Agro-Microbial Resource and Application of Agriculture Ministry China Agricultural University Beijing 100094 China 3. Chemical and biological School ShenYang Normal University Shenyang 110034 China

A 324.bp of nifH fragment was PCR amplified from Paenibacillus massiliensis T7 using the universal degenerate primers. The PCR-amplified nifH fragment was labeled with DIG; then used as a probe in Southern blot analysis. Southern blot result showed that there were two positive signals, indicating that there might be two copies of nifH in P. massiliensis T7. A total of 10254.bp DNA sequence containing purD; nifBHDKENX was obtained by five rounds of inverse-PCR amplification. The predicted proteins of nifBHDKENX had high homology with those from other nitrogen-fixing bacteria. Only one putative σ[54.-dependent promoter sequence was detected upstream of the nifB gene; nifBHDKENX were likely to be organized in one operon. Assays of β-galactosidase activity of P. massiliensis T7PB carrying a nifB-lacZ fusion under different concentrations of NH4.[+]; O2 showed that the expression of nifB-lacZ was strongly inhibited by O2.

关键词： Paenibacillus massiliensis T7, nifBHDKENX, nifB-lacZ, inverse-PCR.

A measure of semantic similarity between gene ontology terms based on semantic pathway covering

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Progress in Natural Science:Materials International 2006年第07期16卷 721-726页

作者： LI Rong, CAO Shunliang, LI Yuanyuan, TAN Hao, ZHU Yangyong, ZHONG Yang and LI Yixue ( Department of Computing and Information Technology, Fudan university, Shanghai 2004.3, china Shanghai center for Bioin-formation Technology, Shanghai 200235, china School of Life Sciences, Fudan university, Shanghai 2004.3, china Bioinfor-rnation center of Shanghai Institute for biological Sciences, Chinese Academy of Sciences, Shanghai 200031, china) [a]Department of Computing an Information Technology Fudan University Shanghai China [b]Shanghai center for Bioinformation Technology Shanghai China [c]School of Life Sciences Fundan University Shanghai China [d]Bioinformation center of Shanghai Institute for biological Sciences Chinese Academy of Sciences Shanghai China

Semantic similarity between Gene Ontology (GO) terms is critical in resolving semantic heterogeneousness when integrating heterogeneous biological databases. Traditionally, distance based and information content based measures are two major methods. In this paper, a new method based on semantic pathway covering is proposed and an algorithm, COMBINE algorithm, is presented, which considers information contents of two given nodes and those of all nodes included in the two nodes' pathways. Experiments show that COMBINE algorithm obtains the highest correlation index compared with those distance based and information content based algorithms.

关键词： Gene Ontology semantic similarity measure information content.

Screening of Proteins Interacting with Nonstructural 1 Protein of H5N1 Avian Influenza Virus from T7-phage Display Library

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Chemical Research in Chinese Universities 2012年第1期28卷 103-107页

作者： ZHU Chun-yu1,2, SUN Ting-ting2, ZHAO Jian1,2, WANG Ning1,2, ZHENG Fang-liang1, AI Hai-xin1, ZHU Jun-feng1,2, WANG Xiao-ying3, ZHU Ying4. WU Jian-guo4.and LIU Hong-sheng1,2 1. Key Laboratory of Animal Resource and Epidemic Disease Prevention of Liaoning Province, 2. Research center for Computer Simulating and Information Processing of Bio-macromolecules of Liaoning Province, Academy of Science, Liaoning university, Shenyang 110036, P. R. china 3. Institute of Nutrition and Food Safety, Chinese center for Disease Control and Prevention, Beijing 100050, P. R. china 4. State Key Laboratory of Virology, Wuhan university, Wuhan 4.0072, P. R. china Liaoning Univ Acad Sci Key Lab Anim Resource & Epidem Dis Prevent Liaoni Shenyang 110036 Peoples R China Liaoning Univ Acad Sci Res Ctr Comp Simulating & Informat Proc Biomacrom Shenyang 110036 Peoples R China Chinese Ctr Dis Control & Prevent Inst Nutr & Food Safety Beijing 100050 Peoples R China Wuhan Univ State Key Lab Virol Wuhan 430072 Peoples R China

Avian influenza virus（AIV） nonstructural 1（NS1） gene was amplified by real-time polymerse chain reac tion（RT-PCR） and inserted into pET28a, then transformed into E. coli BL21（DE3） competent cell. With the induction of isopropyl-β-D-thiogalactoside（IPTG） and the purification of Ni-NTA column, we finally obtained purified NS1 protein. T7-phage display system was used to screen the proteins that interacted with NS1 from lung cell cDNA li brary. The selected positive clones were identified by DNA sequencing and analyzed by BLAST program in Gene Bank. Two proteins were obtained as NS1 binding proteins, Homo sapiens nucleolar and coiled-body phosphoprotein 1（NOLC1） and Homo sapiens similar to colon cancer-associated antigen. By co-immunoprecipitation and other me thods, Homo sapiens NOLC1 was found to interact with the NS1 protein, the results would provide the basis for fur ther studying biological function of NS1 protein.

关键词： T7-phage display Nonstructural 1 (NS 1) protein Interacting protein

Biomarkers of neurodegenerative disorders: How good are they?

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Cell Research 2004年第5期14卷 347-358页

作者： Varun RACHAKONDA Department of Neurology Baylor College of Medicine Houston TX USA

Biomarkers are very important indicators of normal and abnormal biological processes. Specific changes in pathologies, biochemistries and genetics can give us comprehensive information regarding the nature of any particular disease. A good biomarker should be precise and reliable, distinguishable between normal and interested disease, and differential between different diseases. It is believed that biomarkers have great potential in predicting chances for diseases, aiding in early diagnosis, and setting standards for the development of new remedies to treat diseases. New technologies have enabled scientists to identify biomarkers of several different neurodegenerative diseases. The followings, for instance, are only a few of the many new biomarkers that have been recently identified: the phosphorylated tau protein and aggregated β-amyloid peptide for Alzheimer’s disease (AD), α-synuclein contained Lewy bodies and altered dopamine transporter (DAT) imaging for Parkinson’s disease (PD), SOD mutations for familial amyotrophic lateral sclerosis (ALS), and CAG repeats resulted from Huntington’s gene mutations in Huntington’s disease (HD). This article will focus on the most-recent findings of biomarkers belonging to the four mentioned neurodegenerative diseases.

关键词： Alzheimer’s disease Parkinson’s disease Amyotrophic Lateral Sclerosis Huntington’s disease biomarkers.

miRNAs modulate the drug response of tumor cells

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Science china(Life Sciences) 2009年第9期52卷 797-801页

作者： WU XueMei1,3 & XIAO HuaSheng1,2 1 center of Functional Genomics,Key Laboratory of System Biology,Shanghai Institutes for biological Sciences,Chinese Academy of Sciences,Shanghai 200031,china 2 National Engineering center for Biochip at Shanghai,Shanghai 201203,china 3 Graduate university of Chinese Academy of Sciences,Shanghai 200031,china center of Functional Genomics Key Laboratory of System Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai 200031 China National Engineering center for Biochip at Shanghai Shanghai 201203 China Graduate university of Chinese Academy of Sciences Shanghai 200031 China

Chemotherapy is one of the major treatments of malignant carcinomas. However,its efficiency is affected by both intrinsic and acquired resistance to anticancer drugs. The cellular mechanisms of drug resistance include the overexpression of energy-dependent transporters that eject anticancer drugs from cells such as p-glycoprotein and multidrug resistance related protein (MRP),the mutation of drug targets,the activation of DNA repair pathways,the defects in cellular death pathways and so on. The genetic and epigenetic changes of these genes can lead to cancer drug resistance. Among these mechanisms,microRNAs (miRNAs) which are critical and essential for many important processes such as development,differentiation,and even carcinogenesis have been reported to regulate the chemosen-sitivity of tumor cells. In this paper we briefly review the relationship between miRNA and cancer drug resistance.

关键词： cancer drug resistance miRNAs

Electrophysiological research of synapse formation from beginning to maturity

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Chinese Science Bulletin 1998年第1期43卷 55-59页

作者： XIE Zuoping and ZHENG Yufang State Key Laboratory of Biomembrane and Membrane Biotechnique Department of biological Sciences and Biotechnology, Tsinghua university, Beijing 100084. china State Key Laboratory of Biomembrane and Membrane Biotechnique Tsinghua University Beijing China Department of biological Sciences and Biotechnology Tsinghua University Beijing China

The development of synapses is an important question in neurobiology. We employ patchclamp technique to record MEPCs and EPCs of myoballs in Xenopus cell culture. The rate of EPC/MEPC is related with synapses maturation. Accordingly, we define the mature synapses as those whose rate of presynaptic membrane’s EPC to MEPC is more than 8. The process of maturation needs about 2-5 h after neurites contact with myoballs. We divide the development of synapses into three stages: young, developing and mature. The neurotransmitters stack gradually and increase by hundreds of times along with young synapses growing into maturity. So the process of synapses maturation should include presynaptic membrane specialization, postsynaptic membrane specialization and neurotransmitters stack.

关键词： definition of mature synapse α latrotoxin (α LTX) neurotransmitter stack.

New development of materials used in BFCs

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化工进展 2010年第S1期29卷 551-556页

作者： WANG Li (Faculty of Environmental and biological Engineering,Shenyang university of Chemical Technology,Shenyang,11014.,china)

Electrodes,catalysts,membranes,if present,are three main components in constructing an MFC for harvesting desired maximum power density and achieving higher coulombic efficiency (CE).Great improvements have been made,based on previous researches,in developing and diversifying materials,aside from *** most familiar to us are widely used carbon *** anodes,carbon matrix composites(e.g.,a combination of polyaniline(PANI)with TiO2 using carbon as substrate)have gained special attention,though carbon material itself can exhibit excellent performance by diversifying molecular structures such as carbon nanotubes(CNTs).In the meanwhile,the evolution of MFC architectures,heading to the direction of improving power generation,contributes to the combination of membranes and cathodes from separate modes to diverse assemblies,on which all sorts of catalysts,such as from commonly used Pt to iron phthalocyanine (Pc),metal tetramethoxyphenylporphyrin(TMPP),MnOx,or pyrolyzed iron(Ⅱ)phthalocyanine (pyr-FePc),can be immobilized through synthesis of these catalysts with polymer such as Nafion 117 (Dupont Co.,USA)or tetrafluoroethylen(eTeflon)containing functional groups or Polypyrrol(ePPy).In addition,catholytes with aqueous cathode immersed or flowing through the surface of air-cathode are favorably proposed containing transition metal redox couples or iron chelates.

关键词： BFCs anode cathode membrane catholyte