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31.
Long-term adhesion and survival of dissociated cortical neurons on miniaturised chemical patterns 总被引:1,自引:0,他引:1
The influence of neuron-adhesive pattern geometry on long-term adhesion, survival and pattern compliance of cortical neuronal
tissue was studied over a period of 15 days. The results are relevant for a successful, long-term integration of neuronal
cells with electrodes from micro-electronic devices. Microwells (depth 0.5μm), with diameters of 25, 50, 100 and 150 μm and
spacing distances of 15, 30, 60 and 90 μm, were etched in a neuron-repellent fluorocarbon (FC) layer and coated with neuron-adhesive
polyethylenimine (PEI). Results showed that adhesion, survival and compliance to the underlying patterns were geometry-and
time-dependent. After 1 day, adhesion was inversely proportional to the diameter of the microwells, thus favouring the 25
μm microwells. However, adhesion was best on 50 μm microwells after 15 days. Survival of neurons was limited on 25 μm microwells
(viability function V(D, T) was 0.08), as opposed to the better survival on 150 μm microwells (V(D, T) was 0.25) after 15
days. In summary, the study shows that the chemical patterns with microwells of 150 μm diameter (90 μm spacing gap) are most
suitable for application on neuro-electronic devices owing to the better long-term survival and high pattern compliance of
the neuronal cells. 相似文献
32.
Mayne M Moffatt T Kong H McLaren PJ Fowke KR Becker KG Namaka M Schenck A Bardoni B Bernstein CN Melanson M 《European journal of immunology》2004,34(4):1217-1227
DNA microarray profiling of CD4(+) and CD8(+) cells from non-treated relapsing and remitting multiple sclerosis (MS) patients determined that the cytoplasmic binding partner of fragile X protein (CYFIP2, also called PIR121) was increased significantly compared to healthy controls. Western analysis confirmed that CYFIP2 protein was increased approximately fourfold in CD4(+) cells from MS compared to inflammatory bowel disorder (IBD) patients or healthy controls. Because CYFIP2 acts as part of a tetrameric complex that regulates WAVE1 activation we hypothesized that high levels of CYFIP2 facilitate T cell adhesion, which is elevated in MS patients. Several findings indicated that increased levels of CYFIP2 facilitated adhesion. First, adenoviral-mediated overexpression of CYFIP2 in Jurkat cells increased fibronectin-mediated adhesion. Secondly, CYFIP2 knock-down experiments using antisense oligodeoxynucleotides reduced fibronectin-mediated binding in Jurkat and CD4(+) cells. Thirdly, inhibition of Rac-1, a physical partner with CYFIP2 and regulator of WAVE1 activity, reduced fibronectin-mediated adhesion in Jurkat and CD4(+) cells. Finally, inhibition of Rac-1 or reduction of CYFIP2 protein decreased fibronectin-mediated adhesion in CD4(+) cells from MS patients to levels similar to controls. These studies suggest that overabundance of CYFIP2 protein facilitates increased adhesion properties of T cells from MS patients. 相似文献
33.
Takahashi HK Xue D Iwagaki H Tamura R Katsuno G Yagi T Yoshino T Mori S Nishibori M Tanaka N 《Clinical immunology (Orlando, Fla.)》2005,115(1):85-92
Prostaglandin E1 (PGE1) has therapeutic value for transplantations due to its microvascular activity. Interleukin (IL)-18, which is elevated in plasma during the acute rejection after organ transplantation, elicits the expression of intercellular adhesion molecule (ICAM)-1, B7.1, B7.2, CD40, and CD40 ligand (CD40L) on monocytes as well as the production of interferon (IFN)-gamma and IL-12 and proliferation of T-cells during the human mixed lymphocyte reaction (MLR) in an in vitro model of acute rejection. In contrast, PGE1 inhibits all the adhesion molecule expression, cytokine production and T-cell proliferation in the presence of IL-18. The effects of PGE1 depend on stimulation of the IP/EP2/EP4-receptor, and thus, PGE1 might have therapeutic potential for treating acute rejection due to its immune regulatory effect. 相似文献
34.
右旋糖酐40、70对红细胞与内皮细胞粘附的影响 总被引:1,自引:0,他引:1
采用流室显微观察系统,定量研究右旋糖酐40(DX40)和右旋糖酐70(DX70)对红细胞与内皮细胞动态粘附特性的影响。统计分析处理数据,得到反映切应力与细胞间动态粘附数关系的经验公式及粘附特征常数a,b值。a值反映红细胞的初始粘附数,b值反映随切应力增大,粘附数减小的速率。DX70实验组的a值大于DX40组的,而b值的情况相反。故结果显示切应力越大,粘附的红细胞越少;DX40使红细胞的粘附明显减少;DX70使红细胞粘附显著增加。由此提示不同长度的细胞桥接分子对红细胞的粘附影响不同,且临床上选用DX40作血浆扩容剂较DX70优越得多 相似文献
35.
Protein kinase mediators of integrin signal transduction 总被引:6,自引:0,他引:6
Protein kinases are important mediators of signal transduction initiated by soluble growth factors and cytokines. Cellular
interactions with the extracellular matrix are mediated largely by members of the integrin class of cell adhesion molecules,
which also subsume signal transduction functions required for cell growth, differentiation, and survival. Here we review the
involvement of protein kinases in mediating integrin intracellular signal transduction and the possible role for these molecules
in regulating integrin adhesion. Although in most cases mechanistic details are incomplete, the emerging theme of protein
kinases mediating cross-talk between growth factor receptor and integrin signalling systems provides a timely backdrop against
which to present new developments in this area. The contribution of the actin cytoskeleton to integrin signal transduction
is discussed, with respect to the concept of ’solid-state’ signalling providing a mechanism for imposing order on the protein-protein
interactions which underlie signal discrimination. Moreover, we review evidence that dysregulated integrin signalling contributes
to pathological processes including arthritis, thrombasthenia, leucocyte adhesion deficiencies, and tumour angiogenesis and
invasion.
Received: 14 May 1996 / Accepted: 2 July 1996 相似文献
36.
Purification of P-selectin (CD62P) from human platelets 总被引:1,自引:0,他引:1
Summary A method is described for immunoaffinity purification of P-selectin from outdated human platelets. 相似文献
37.
本文通过Percoll梯度离心法分离获得大鼠中性粒细胞(PMNS)后,采用PMNS与玻璃珠粘附的模型,通过给予Dex及糖皮质激素受体(GR)阻断剂Mifepristone(RU_(38486))研究大鼠PMNS粘附过程中GR的作用。结果显示,Dex可以明显抑制PMNS的粘附,其作用随着Dex浓度的增大而增强;单纯给予不同浓度的RU_(38486)未发现明显的PMNS粘附增强,说明RU_(38486)本身对离体的PMNS粘附没有明显的作用;若同时给予Dex和RU_(38486),则Dex抑制PMNS粘附的作用逐渐减小,直至完全逆转。该结果强烈提示:糖皮质激素(GC)具有抑制PMNS粘附的作用,其作用是通过GR介导的,当GR被阻断时,这一抑制作用减弱,甚至消失。 相似文献
38.
Hassanein H Hanallah S El-Ahwany E Doughty B El-Ghorab N Badir B Sharmy R Zada S 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2001,109(5):376-382
In this work, the changes in expression of the adhesion molecules ICAM-1/LFA-1 on inflammatory cells of the liver were studied by immunohistochemistry. Mice sensitized with SEA and infected with S. mansoni and S. mansoni-infected controls were examined from day 35 to day 56 postinfection. A significant upregulation of ICAM-1 and LFA-1 in both the SEA group and the infected control group started shortly after egg deposition at day 35 and persisted up to day 56 p.i. Notably, both ICAM-1 and LFA-1 expression peaks were shifted earlier to day 38 p.i. in the SEA group compared to day 40 in the infected control group. The distribution of ICAM-1 and LFA-1 in both groups was comparable. At the early phase of infection before granuloma formation, both ICAM-1 and LFA-1 were detected along the sinusoidal wall of small blood vessels. At the acute cellular granuloma phase, they were homogeneously distributed all over the inflammatory cells, while at the chronic fibrocellular stage a non-homogeneous staining of granuloma cells at the periphery of the granuloma was apparent. The present data suggest that adhesion molecules play a role in the initiation and maintenance of granuloma formation. Thus, the granulomatous hyporesponsiveness induced by sensitization with SEA was associated with reduced expression of adhesion molecules. 相似文献
39.
目的研究路氏乳杆菌(Lactobacillus reuteri,也称罗伊氏乳杆菌)JCM1081菌体表面蛋白对其黏附HT-29细胞的影响。方法将路氏乳杆菌JCM1081菌体进行胰蛋白酶、蛋白酶K处理;用氯化锂和盐酸胍对乳杆菌表面的蛋白进行抽提,进行SDS-PAGE后与黏蛋白受体进行Western blot,并对杂交阳性蛋白进行质谱分析鉴定。结果路氏乳杆菌JCM1081菌体经胰蛋白酶、蛋白酶K处理后,其对HT-29细胞的黏附力显著下降(P<0.01);用氯化锂去除路氏乳杆菌JCM1081菌体外表面的S层蛋白后,路氏乳杆菌JCM1081对HT-29细胞的黏附力无显著变化;Western blot结果显示相对分子质量(Mr)为29×103和14×103的两种菌体表面蛋白与黏蛋白受体杂交中出现了强阳性;质谱分析结果显示29×103蛋白与路氏乳杆菌ATCC55730的h0793蛋白相似性高达71.1%。结论路氏乳杆菌JCM1081菌体表面的蛋白参与了乳杆菌的黏附,其中29×103和14×103的两种胞壁表面蛋白能够特异地识别黏蛋白受体并与之结合,29×103蛋白属ABC转运蛋白家族。 相似文献
40.
During embryogenesis, colonization of the thymic rudiment by hemopoietic progenitor cells depends on the adhesion of these cells to the jugular endothelium. Previously, we showed that progenitor T cells (pro-T cells) interact with α6 integrins present on vascular endothelium. Here, we demonstrate that anti-α6 integrin antibodies reduced the number of thymocytes up to 80 % in a congenic mouse model for thymus colonization by pro-T cells. In organotypic thymus cultures, the anti-α6 integrin antibodies did not influence T cell development and proliferation. From this, we conclude that α6 integrin participates in thymus homing. During mouse thymus ontogeny, α6 integrin mRNA and protein expression was found as early as day 10 of development; at day 11, perithymic endothelial cells were α6 integrin positive. Two α6 integrin mRNA exist which are produced by alternative exon usage. The longer form, α6, integrin, predominates during early embryonic stages, while the shorter α6A form was present later during development. Although α6, integrins can be displayed by immature thymocytes, strongest expression was found on intra- and perithymic vascular endothelium. These data suggest that α6 integrins are involved in the homing of pro-T cells to the developing thymus by mediating adhesion of pro-T cells to the vascular endothelium. 相似文献