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Identification of tumor metastasis-related gene TMSG-1 by mRNA differential display

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Science China(Life Sciences) 2002年第5期45卷 553-560页

作者：马春树方伟岗崔湘琳刘宇欣由江峰吴秉铨郑杰王洁良 Department of Pathology Health Science Center Peking University Beijing China

To investigate genes involved in cancer metastasis, mRNA differential display was used to compare the levels of gene expression of two cancer sublines derived from prostate carcinoma cell PC-3M that had different metastatic potentials. The differentially expressed genes were confirmed by Northern blot, and sequenced. The full-length cDNA of a tumor metastasis suppressor gene (TMSG-1) was obtained by using EST assembling and verified by RT-PCR and sequencing. The results showed that expression levels of TMSG-1 were lower in the highly metastatic cell line 1E8, compared with the non-metastatic cell line 2B4. The difference was significant. Full-length cDNA of TMSG-1 was about 2 kb, containing an open reading frame that encoded a protein of 230 amino acids. GenBank Blastn showed no marked homology with known genes. The functional prediction of amino acids sequence encoded by TMSG-1 gene indicated TMSG-1 protein was transmembrane protein, with 3 transmembrane domains, 3 putative protein kinase phosphorylation sites, 2 casein kinase II phosphorylation sites and 1 N-myristoylation site. The pattern of TMSG-1 expression in 6 types of human tumor tissues indicated levels of transcripts were the highest in prostate carcinoma. TMSG-1 had lower expression in metastases of lung carcinoma compared to primary lung carcinoma. Similarly the expression levels were higher in well-differentiated colon carcinoma than that in poorly differentiated colon carcinoma. TMSG-1 could also be detected in breast, ovarian, and pancreatic carcinoma. In 9 samples of primary gastric carcinoma tissues, RT-PCR and densitometric analysis demonstrated TMSG-1 expression levels in samples with lymph node metastases had a decreased tendency, compared to those without lymph node metastases. The difference was significant by student's t test (p<0.05). These results indicated TMSG-1 expression levels were inversely correlated with tumor metastatic potential.

关键词： prostate cancer, cancer metastasis, mRNA differential display.

Influence of Cr-doping on the magnetic and electrical transport properties of Nd_(0.75)Na_(0.25)MnO_3

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Journal of Rare Earths 2011年第3期29卷 230-234页

作者：张兴华李志青 School of Materials Science and Engineering Hebei University of Technology Tianjin key Laboratory of Low Dimensional Materials Phys-ics and Preparing Technology Tianjin University

Polycrystalline Nd0.75Na0.25Mn1-xCrxO3（0≤x≤0.1） samples were prepared by sol-gel method and their magnetic and electrical transport properties were investigated *** parent compound with x=0 was a charge ordered manganite and the charge ordering transition occurred at 170 *** lower Cr concentration（x0.03）,the samples preserved the charge ordering features of the parent compound,but the charge ordering transition temperature decreased with increasing x,in particular from 170 K for x=0 to 154 K for x=*** the x≥0.03 samples,paramagnetic to ferromagnetic phase transition took place and the Curie temperature increased from 112.8 K for x=0.04 to 125.5 K for x=*** electrical transport properties were also influenced by Cr *** x0.03,the samples displayed insulator characteristics below 300 *** x=0.04,the sample showed insulator-metal transition around 75 *** x≥0.05,the insulator-metal transition disappeared and the compounds showed insulator features *** magnetic and electrical properties could be well explained by the phase separation scenario.

关键词： rare earth manganites charge ordering phase separation

Microstructure of stress-induced martensite in nanocrystalline NiTi shape memory alloy

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Rare Metals 2014年第4期33卷 379-382页

作者： Xiao-Bin Shi Li-Shan Cui Zhen-Yang Liu Da-Qiang Jiang Xiao-Dong Han State key Laboratory of Heavy Oil Processing China University of Petroleum Institute of Microstructure and Properties of Advanced Materials Beijing University of Technology

The microstructure of stress-induced martensite （SIM） in the nanocrystalline NiTi alloy was investigated by means of transmission electron microscopy （TEM）. The result shows that the multi-variant structure of the martensite is suppressed and only single-variant martensitic twins form after tensile deformation when the grain size is smaller than 80 nm. The normal directions of the （001）B19, twin planes are all. within the range of 45° from the axial direction of the wire. The angle between twin crystals （111）M and （111）x of the SIM is also found to be smaller than that of thermally induced martensite in nanocrystalline NiTi.

关键词： Martensitic transformation Microstructure Shape memory alloys Twin

CYCLIC CODES OVER FORMAL POWER SERIES RINGS

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Acta Mathematica Scientia 2011年第1期31卷 331-343页

作者： Dougherty Steven T. 刘宏伟 Department of Mathematics University of Scranton Department of Mathematics Huazhong Normal University

In this article, cyclic codes and negacyclic codes over formal power series rings are studied. The structure of cyclic codes over this class of rings is given, and the relationship between these codes and cyclic codes over finite chain rings is obtained. Using an isomorphism between cyclic and negacyclic codes over formal power series rings, the structure of negacyclic codes over the formal power series rings is obtained.

关键词： Finite chain rings cyclic codes negacyclic codes γ-adic codes

Two New Eremophilenolides from Ligularia tongolensis

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chinese Chemical Letters 2005年第8期16卷 1053-1055页

作者： Yi Feng HAN Dong Qing FEI Kun GAO Zhong Jian JIA State key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical Engineering Lanzhou University Lanzhou 730000

Chemical investigation of L. tongolensis afforded two new eremophilenolides, which were identified as 3β-（2＇-methylbutanoyloxy）-8βH-eremophil-7（11）-en-12, 8α（14, 6α）-diolide （1）and 8βH-eremophil-3, 7（11）-dien-12, 8α （14, 6α）-diolide （2）. Their structures were established by spectroscopic methods including 2D NMR experiments.

关键词： Ligularia tongolensis Compositae eremophilenolide sesquiterpene.

Analysis of Wave Nonlinear Dispersion Relations

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China Ocean Engineering 2005年第1期19卷 167-174页

作者：李瑞杰陶建福 Laboratory of Ocean Environment Hohai University Nanjing 210098 China Institute of Physical Oceanogranhy Hohai University Nanjing 210098 China

The nonlinear dispersion relations and modified relations proposed by Kirby and Hedges have the limitation of intermediate minimum value. To overcome the shortcoming, a new nonlinear dispersion relation is proposed. Based on the summarization and comparison of existing nonlinear dispersion relations, it can be found that the new nonlinear dispersion relation not only keeps the advantages of other nonlinear dispersion relations, but also significantly reduces the relative errors of the nonlinear dispersion relations for a range of the relative water depth of 1

关键词： wave nonlinear dispersion relation modified dispersion relation calculation and analysis

Reaction mechanism in high Nb containing TiAl alloy by elemental powder metallurgy

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中国有色金属学会会刊：英文版 2006年第4期16卷 853-857页

作者：王衍行林均品贺跃辉王艳丽林志陈国良 State key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing Beijing 100083 China State key Laboratory of Powder Metallurgy Ce ntral South University Changsha 410083 China

High Nb containing TiAl alloy was fabricated in argon atmosphere by reactive hot pressing process. Reaction mechanism was investigated by means of microstructural analyses and thermodynamic calculations. The results show that it is feasible to prepare high Nb containing TiAl alloy with fine lamellar colonies by reactive hot pressing process. The reaction between Ti and Al powders is dominant in Ti-Al-Nb system. Nb powders dissolve into the Ti-Al matrix by diffusion. Pore nests are formed in situ after Nb powders diffusion. The hot pressing atmosphere is optimized by thermodynamic calculations. Vacuum or argon protective atmosphere should be adopted.

关键词： TiAl合金铌粉末冶金反应机理热力学

Synthesis,Crystal Structure and Magnetic Properties of a Cobalt(Ⅱ)Coordination Polymer with4,4'-(Propane-2,2-diyl)dibenzoate and4,4'-Bis(1-imidazolyl)biphenyl

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chinese Journal of Structural Chemistry 2013年第10期32卷 1579-1585页

作者：刘光祥 School of Biochemical and Environmental Engineering Nanjing Xiaozhuang University

A novel coordination polymer, {[Co（CBA）（BIMB）0.5]＇H20}n （1, H2CBA = 4,4＇- （propane-2,2-diyl）dibenzoic acid, and BIMB = 4,4＇-bis（1-imidazolyl）biphenyl）, has been hydro- thermally prepared and characterized by IR spectroscopy, elemental analysis and single-crystal X-ray diffraction. The crystal is of monoclinic system, space group P2/c with a = 14.909（3）, b = 7.1963（15）, c = 24.592（5） A, β = 104.312（2）, V = 2556.5（9） A3, C26H23N2OsCo, Mr = 502.39, Dc = 1.305 g/cm3, F（000） = 1040,μ = 0.708 mm-1 and Z = 4. The final R= 0.0580 and wR = 0.1605 for 3228 observed reflections （1 〉 2a（I））. Single-crystal structure analysis shows that complex 1 exhibits a three-dimensional 2-fold interpenetrating pillared helical-layer open framework of a-Po topology based upon binuclear paddlewheel units. Moreover, its magnetic properties have also been investigated.

关键词： cobalt coordination polymer crystal structure,4,4'-(propane-2,2-diyl)dibenzoic acid magnetism

Structural Effects of L16Q, S20G, and L16Q-S20G Mutations on hlAPP： A Comparative Molecular Dynamics Study

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chinese Journal of Chemistry 2012年第2期30卷 241-248页

作者： Wang,Mian Yang,Jipeng Wang,Jianyi Wang,Xiaojuan School of Chemistry and Chemical Engineering Guangxi UniversityNanningGuangxi 53004China Jiyuan Vocational and Technical College JiyuanHenan 459000China

The conformation change picture of human islet amyloid polypeptide （hlAPP） is outlined using molecular dynamics simulation, and the structural influences of L16Q, S20G, and L16Q-S20G mutations on the conformation of hlAPP are analyzed. Particularly, the conformational changes of the amyloidogenic-related regions of residues 15-- 17 and 20--29 are emphasized. Our studies find that, for WT hlAPP, residues 15--17 always maintain a stable a-helix structure, residues 20--25 structurally fluctuate between turn and 5-helix, and residues 26--29 mainly adopt coil and bend structures. The hydrogen bonds between the polar groups of hlAPP, long-rang van der Waals forces between the residues, and hydrophobic interactions between the residues of hlAPP are important driving forces to maintain the secondary structure of hlAPP. The replacement of leucine 16 by glutamine stabilizes the helix structure of residues 15--17 and 20--23 of hlAPP monomer, and the structure of residues 24--29 fluctuates be- tween helix and turn. The relatively stable helix structures of residues 15--17 and 20--29 are supposed to be beneficial for L16Q hlAPP to resist the aggregation as observed in the experiment. The substitution of serine20 by glycinc drives residues 15--17 and 20--29 of hlAPP to transform from helix structure to β-strands or coil structures with higher extension and flexibility, which may promote the aggregation of hlAPP as the experiments reported. These results are significant to understand the aggregation mechanism of hlAPP monomer into the dimer, trimer, oligomers and fibrils associated with the type 2 diabetes at the atomic level.

关键词： hIAPP wild type mutant molecular dynamics simulation