Anti-CD44 mAb remodels biological behaviors of spheroid cells with stemness from human ovarian cancer cell line SKOV-3

There is accumulating evidence that cancer stem cells (CSCs) play an important role in tumor progression. Novel strategies targeting CSCs have been widely researched. In the present study, we explored whether such CSCs existed in human ovarian cancer (OVCA) cell line and whether anti-CD44 antibody had effects on such subpopulation. We isolated and identified spheroid cells from SKOV-3. Then we used A3D8, an anti-CD44 mAb to treat spheroid cells with so-called "stemness". Effects of A3D8 on spheroid cells’ biological behaviors were examined. Our findings showed that there was a small subpopulation that had so-called "stemness" in SKOV-3 cell line. Against spheroid cells, A3D8 can (1) inhibit cell proliferation; (2) change cell cycle distribution and expression of p21, CDK2 and cyclinA; (3) enhance cisplatin (DDP)-induced apoptosis; (4) promote cell differentiation; (5) inhibit clone formation efficiency; (6) reduce invasive efficacy; (7) inhibit tumorigenicity. Thus, to sum up points which we have just showed, spheroid cells isolated from SKOV-3 can be used as an appropriate in vitro model for relevant study of human ovarian CSCs. And our results reasoned that anti-CD44 therapy may become a potential promising strategy for OVCA treatment.     

《中国学术期刊(光盘版)》评析

就《中国学术期刊 (光盘版 )》的内容、特点、检索功能及其对图书馆产生的影响和效益等问题进行了介绍和评析。     

Two tyrosines in CD3s-ITAM are required to induce T lymphocyte apoptosis

CD3ε of T cell antigen receptor complex (TCR/CD3) plays an important role in the resembling of the complex and activation signaling through its conservative immunoreceptor tyrosine-based activation motif (ITAM) in the cytoplasmic tall. Previous study showed that a chimera molecule, consisting of the extracellular-transmembrane domain of human CD8α fused to the cytoplasmic domain of CD3ε, induced apoptosis of T lymphocytes, indicating that apoptotic signals were transduced through the CD3ε-ITAM. To elineate involvement of the two tyrosines in apoptotic signaling pathway, cDNAs with mutations at Y170F, Y181F and Y170F/Y181F in CD8ε-ITAM were made by point mutation and PCR, and then cloned into pcDNA3 eukaryotic expression vectors. Stable expression cell lines were established after transfection of the expression vectors into CD8^- Jurkat T lymphocytes. Stimulation of these cell lines with anti-CD8 monoclonal antibody showed that only the cells with expression of wild type chimera CD8-ε died by apoptosis, but not those cells with expressions of mutated CD8-ε chimera, indicating that the two tyrosines in CD3ε-ITAM were required for the apoptotic signal transduction in T lymphocytes.     

Circular dichroism spectra of different structures formed by the oligonucleotides

Under different conditions, oligonucleotides can form several different DNA structures such as duplex, triplex and quadruplex. All these structures exhibit an obvious difference in their CD spectra. The common characteristic is that they show a negative band at 240 nm, while in the range of 260–300 nm, the spectra are different from each other. Many factors such as chain direction, sugar puckering mode, orientation of the glycosyl bond, base stacking and sequence can affect their conformation and then show diversity and complexity in their spectra. By studying and comparing these spectra, more information about their conformations can be obtained to help predict some new structures. Furthermore, the spectra can also provide a base to study their potential biological functions.     

31P-NMR技术考察CD/SF 5W/30通用内燃机油中ZDDP在行车试验中的氧化降解机理

文中应用³¹P-NMR技术考察了CD/SF 5W/30通用内燃机油中二烷基二硫代磷酸锌（ZDDP）添加剂在行车试验条件下的氧化降解机理。研究结果表明，ZDDP的氧化降解，首先是形成硫代磷酸酯以及硫代磷酸盐，其最终氧化降解产物是磷酸酯（盐）。ZDDP的氧化降解是导致内燃机油失效的重要原因。     

浅谈图书馆随书光盘的管理模式

介绍了光盘图书的特点、随书光盘的管理形式和光盘图书使用和保管的正确方法．分析了光盘图书收藏管理中的常见问题，阐述了提高随书光盘利用率的措施。     

Evidence for existence of a close association between CD14 and CXCR4 on monocytic cell line U937

The surface expression of HIV-1 coreceptors (CXCR4 and CCR5) on monocytes can be regulated by the ligand of CD14,and the susceptibility of the cells to HIV-1 is then changed.Our previous study found that monoclonal antibody against CD14 could dramatically inhibit CXCR4-mediated chemotaxis and cell-cell fusion.Based on these studies,we explored potential relationship between CD14 and CXCR4 on monocytic cell line U937.Flow cytometry analysis showed that anti-CXCR4 monoclonal antibody (mAb) 12G5 strongly inhibited binding of the FITC-conjugated anti-CD14 monoclonal antibodies (TUK4 and UCHM1) to U937,while another CX- CR4-specific mAb B-R24 did not show any effect on this binding.On the other hand,two anti-CD14 monoclonal antibodies (TUK4 and UCH-M1) obviously inhibited the binding of the PE-conjugated anti-CXCR4 mAb 12G5 to U937 but did not inhibit the binding of mAb 12G5 to CXCR4-transfected 3T3 cells (3T3.T4.CXCR4),which indicates that the blocking of mAb 12G5 binding to CXCR4 by CD14- specific mAbs is not involved in the possibility that CD14-specific mAbs directly bind to CXCR4.These results suggested existence of a close association between CD14 and CXCR4 on monocytic cell line U937.     

基于CSMA/CD协议的以太网络性能仿真技术研究

根据以太网络的随机访问方式和到达帧的突发特性 ,证明了以太网络的帧到达过程服从泊松分布 ,提出了以太网络系统的排队模型 ,并对基于 CSMA/ CD协议的以太网络系统性能进行了仿真 ,研究表明这种仿真技术在评价网络性能时是一种非常有效和简单的方法