Polypeptide composition of normal and neoplastic human breast tissues and cells analyzed by two-dimensional gel electrophoresis

Summary The protein populations of epithelial cells cultured from two neoplastic and five non-neoplastic human breast tissues were resolved and displayed by two-dimensional polyacrylamide gel electrophoresis and silverstaining. With a computer-based image analysis system, we identified eight polypeptides which are present in both of the neoplastic cell lines, but absent from all five of the cultures of non-neoplastic breast cells. The eight polypeptides are not unique to cells cultured from neoplastic breast, because they are also found in cells cultured from non-breast tissues, both neoplastic and non-neoplastic. Two of the eight polypeptides ( M_r 25,000/pI 4.4 and M_r 31,000/pI 5.5) are present in the patterns of whole tissue samples from infiltrating ductal carcinomas and absent in most normal breast tissue.     

金属表面TiO2薄膜的溶胶-凝胶法制备及其血液相容性研究

通过溶胶 凝胶法制备TiO2 薄膜对 316L不锈钢和NiTi形状记忆合金进行表面改性处理。研究发现 ,经 5 0 0℃处理 1h的薄膜结构致密 ,膜层均匀平滑 ,薄膜主要由锐钛矿相TiO2 构成 ,随热处理温度的提高 ,锐钛矿相逐渐转变为金红石相。电化学腐蚀和动态凝血时间及溶血率测试表明 ,通过溶胶 凝胶法制备TiO2 膜进行表面改性的 316L不锈钢和NiTi合金的抗模拟体液腐蚀性提高 ,动态凝血时间延长 ,溶血率下降 ,说明溶胶 凝胶法制备TiO2 膜可以提高金属植入物的血液相容性     

Thromboresistant properties of hydrophilic gels

The thromboresistant properties of hydrophilic gels based on copolymers of nitrogen-containing heterocyclic vinyl compounds with vinyl monomers were investigated. The hydrophilic gels were shown to prevent adsorption of fibrinogen, activation of procoagulants, and adhesion of platelets. Hydrogen surfaces possess selective affinity for plasma albumin. The authors consider that the thromboresistant effect of hydrophilic gels is due to the competitive action of plasma albumin. Modification of hydrophilic gels increases their thromboresistant properties.Laboratory of Thromboresistant Materials, Institute of Transplantation of Organs and Tissues, Ministry of Health of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR A. M. Chernukh.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 89, No. 3, pp. 296–298, March, 1980.     

等离子体表面改性涤纶材料的血浆蛋白吸附与血小板黏附行为研究

采用等离子体表面接枝改性技术在涤纶 (聚对苯二甲酸乙二醇酯 ,PET)材料表面接枝不同分子量的聚乙二醇 (PEG) ,从表面能与界面自由能的角度分析了血浆蛋白 (纤维蛋白原和白蛋白 )在材料表面的竞争吸附关系 ,结果表明接枝了 PEG长链分子的 PET材料具有优先吸附白蛋白的性质 ,其中接枝 PEG6 0 0 0的 PET优先吸附倾向最明显。预接触白蛋白和纤维蛋白原的 PET材料表面的血小板黏附实验表明 :吸附白蛋白的表面能够显著抑制血小板的黏附和聚集 ,表现出好的血液相容性 ,而吸附了纤维蛋白原的材料表面具有降低血液相容性的性质。     

Comparative proteomic analysis of Vibrio cholerae O139, O22, O155 and El Tor biotype epidemic strains

Cholera ,as one of the most severe epidemic dis-eases inthe world,can occurin a short time ,andspread quicklyto a wide region.Until 1992 ,onlyV.choleraeserogroup O1 was recognized as thecause of epidemic cholera . However in October1992 ,a major outbreak of a cholera-like illnesscaused by a newserogroupstrain ofV.choleraee-mergedinIndia and Bangladesh.In contrast to allpreviously reported non-O1 strains , which induceonly sporadic cases of human diarrhea without epi-demic potential ,the new…     

红细胞聚集增高与纤维蛋白原的关系及其对心绞痛患者发病的影响

目的 :探讨红细胞聚集改变与纤维蛋白原的关系及其对心绞痛发病的影响。方法 :测定 80例不稳定性心绞痛患者和 40例健康人的红细胞聚集指数 (光密度法 )、红细胞变形指数 (激光衍射法 )、血浆及全血粘度 (旋转式粘度计 )和纤维蛋白原 (双缩脲法 )。结果 :不稳定性心绞痛患者红细胞聚集指数和全血粘度 ( 4 0s- 1 )及纤维蛋白原浓度均高于对照组 (P均 <0 .0 1～ 0 .0 5 ) ,且红细胞聚集指数与纤维蛋白原呈直线正相关 ,与全血粘度 ( 4 0s- 1 )无相关性。结论 :纤维蛋白原含量增加是红细胞聚集增强的主要原因之一 ;红细胞聚集能力增强导致血液高粘滞 ,与心绞痛发作有关 ;选择 10s- 1 以下切变率测定低切全血粘度 ,利于观察全血粘度与红细胞聚集的关系     

The effect of surface chemistry modification of titanium alloy on signalling pathways in human osteoblasts

Establishing and maintaining mature bone at the bone–device interface is critical to the long-term success of prosthesis. Poor cell adhesion to orthopaedic and dental implants results in implant failure. Considerable effort has been devoted to alter the surface characteristics of these biomaterials in order to improve the initial interlocking of the device and skeleton. We investigated the effect of surface chemistry modification of titanium alloy (Ti–6Al–4V) with zinc, magnesium or alkoxide-derived hydroxy carbonate apatite (CHAP) on the regulation of key intracellular signalling proteins in human bone-derived cells (HBDC) cultured on these modified Ti–6Al–4V surfaces. Western blotting demonstrated that modifying Ti–6Al–4V with CHAP or Mg results in modulation of key intracellular signalling proteins. We showed an enhanced activation of Shc, a common point of integration between integrins and the Ras/Mapkinase pathway. Mapkinase pathway was also upregulated, suggesting its role in mediating osteoblastic cell interactions with biomaterials. The signalling pathway involving c-fos (member of the activated protein-1) was also shown to be upregulated in osteoblasts cultured on the Mg and CHAP modified Ti–6Al–4V. Thus surface modification with CHAP or Mg may contribute to successful osteoblast function and differentiation at the skeletal tissue–device interface.     

Engineered human dicentric chromosomes show centromere plasticity

The centromere is essential for the faithful distribution of a cell's genetic material to subsequent generations. Despite intense scrutiny, the precise genetic and epigenetic basis for centromere function is still unknown. Here, we have used engineered dicentric human chromosomes to investigate mammalian centromere structure and function. We describe three classes of dicentric chromosomes isolated in different cell lines: functionally monocentric chromosomes, in which one of the two genetically identical centromeres is consistently inactivated; functionally dicentric chromosomes, in which both centromeres are consistently active; and dicentric chromosomes heterogeneous with respect to centromere activity. A study of serial single cell clones from heterogeneous cell lines revealed that while centromere activity is usually clonal, the centromere state (i.e. functionally monocentric or dicentric) in some lines can switch within a growing population of cells. Because pulsed field gel analysis indicated that the DNA at the centromeres of these chromosomes did not change detectably, this switching of the centromere state is most likely due to epigenetic changes. Inactivation of one of the two active centromeres in a functionally dicentric chromosome was observed in a percentage of cells after treatment with Trichostatin A, an inhibitor of histone deacetylation. This study provides evidence that the activity of human centromeres, while largely stable, can be subject to dynamic change, most likely due to epigenetic modification.     

The RNA helicase, nucleotide 5'-triphosphatase, and RNA 5'-triphosphatase activities of Dengue virus protein NS3 are Mg2+-dependent and require a functional Walker B motif in the helicase catalytic core

The nonstructural protein 3 (NS3) of Dengue virus (DV) is a multifunctional enzyme carrying activities involved in viral RNA replication and capping: helicase, nucleoside 5'-triphosphatase (NTPase), and RNA 5'-triphosphatase (RTPase). Here, a 54-kDa C-terminal domain of NS3 (DeltaNS3) bearing all three activities was expressed as a recombinant protein. Structure-based sequence analysis in comparison with Hepatitis C virus (HCV) helicase indicates the presence of a HCV-helicase-like catalytic core domain in the N-terminal part of DeltaNS3, whereas the C-terminal part seems to be different. In this report, we show that the RTPase activity of DeltaNS3 is Mg2+-dependent as are both helicase and NTPase activities. Mutational analysis shows that the RTPase activity requires an intact NTPase/helicase Walker B motif in the helicase core, consistent with the fact that such motifs are involved in the coordination of Mg2+. The R513A substitution in the C-terminal domain of DeltaNS3 abrogates helicase activity and strongly diminishes RTPase activity, indicating that both activities are functionally coupled. DV RTPase seems to belong to a new class of Mg2+-dependent RTPases, which use the active center of the helicase/NTPase catalytic core in conjunction with elements in the C-terminal domain.     

人晶状体上皮细胞蛋白质组的双向电泳和质谱鉴定

目的： 建立人晶状体上皮细胞蛋白质组研究体系，探讨双向电泳和质谱鉴定技术在人晶状体上皮细胞蛋白质组研究中的作用。 方法: 体外培养人晶状体上皮细胞株，用两种不同方法提取总蛋白，进行固相pH梯度(IPG)等电聚焦双向凝胶电泳，凝胶通过GS-800扫描仪（Bio-Rad）获取图像并使用PDQuest专业图像分析软件分析。在此基础之上，胰酶消化蛋白质斑点并进行质谱分析。 结果: 获得了重复性较好的人晶状体上皮细胞蛋白质组电泳图谱。晶状体蛋白质斑点在等电点pH值为4-7、相对分子质量为17-72 kD之间均有分布。其中高丰度蛋白点主要分布于分子量19-50 kD、PI 5-7范围内。2个蛋白点通过质谱分析和数据库的检索得到了初步的鉴定。 结论: 建立起了一个稳定的分析人晶状体上皮细胞蛋白质组学实验体系；为进一步研究人类晶状体在生理状态及白内障等病理条件下的改变提供了蛋白质组学的研究方法和途径。