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1.
AIM:To explore the serum levels of certain adhesion molecules and its significance in acute coronary syndrome(ACS). METHODS:The subjects included 40 patients with acute myocardial infarction(AMI) and 40 patients with unstable angina pectoris (UAP). Among the 80 patients, 60 patients accepted a follow-up 4 months. At the same time we selected 40 controls from people who attended a routine health check in the university. Serum levels of E-selectin, sICAM-1, sVCAM-1 were measured by ELISA.RESULTS:Serum levels of E-selectin, sICAM-1, sVCAM-1 were significantly higher in the ACS group(AMI or UAP) than in the control group. Four months later, the levels of E-selectin, sICAM-1 became significantly lower in the follow-up group than in the ACS group, while sVCAM-1 showed no significant difference. CONCLUSION:Serum levels of E-selectin, sICAM-1 may have certain diagnostic value for ACS, and can be a useful marker reflecting the stability of the disease.  相似文献   
2.
AIM: To study the effect of propolis on the expression of CD54 and activation of NF-κB p65 in lung tissue of acute lung injury (ALI) rats. METHODS: 40 male Wistar rats were divided into 5 groups: normal control, model control, dectancyl group, water soluble derivative of propolis (WSP) group and ethanol extracted propolis (EEP) group. ALI animal model was performed by oleic acid and LPS twice attack. The pathologic slice was observed with light microscope and the NF-κB p65 activity and CD54 expression were tested by immunohistochemistry (SABC and SP). RESULTS: Both EEP and WSP antagonized the lung edema, decreased the inflammation and inhibited the expression of CD54 and activation of NF-κB p65. CONCLUSION: The increase in the expression of CD54 and the activation of NF-κB p65 in the lung tissues of ALI were involved in the formation of ALI. Propolis ameliorated the lung damage, which maybe related to the inhibition of CD54 expression and NF-κB p65 activation.  相似文献   
3.
AIM:To investigate the effect of berberine on IL-1 or tumour necrosis factor (TNF) induced polymorphonuclear leucocyte(PMN)-endothelium adhesion and adhesion molecules.METHODS:Based on the model of human umbilical vein endothelial cell (HUVEC), this study adopted Rose Bengal Stain, cell ELISA, immunocyto-chemical techniques to investigate the effect of berberine on PMN-endothelium adhesion and the expression of cell adhesion molecules (CAMs).RESULTS:Berberine inhibited IL-1, TNF-induced HUVEC adhesion for PMN when pretreated HUVEC and antagonised IL-1, TNF-induced upregulation of ICAM-1 on HUVEC. Meanwhile, TNF-stimulated PMN adhesion for HUVEC and CD18 upexpression on PMN was diminished in the presence of berberine.CONCLUSION: Inhibite PMN-endothelium adhesion by downregulating the CAMs expression to inhibite PMN migration across endothelium is one of the mechanisms of antiinflammation of berberine.  相似文献   
4.
AIM and METHOD: The adhesion behavior of bone marrow stromal cells(BMSC) in children with acute lymphoblastic leukemia(ALL) to bone marrow mononuclear cells(BMMC) and Raji cells were investigated by MTT method. The expression of adhesion molecules ICAM-1 and VCAM-1 were detected by flow cytometry. RESULTS: The adhesion ability of BMSC in acute period of ALL to BMMC was lower than that of control group. The adhesion ability of BMSC in long term remission period of ALL to Raji cells higher than that of control group. The expression of ICAM-1 on the surface of BMSC in acute period of ALL is much lower than that of control group. CONCLUSIONS: The adhesion of BMSC to BMMC or tumor cells in children with ALL was abnormal. The abnormal adhesion behavior might be partially due to the changed expression of adhesion molecules on BMSC.  相似文献   
5.
One of the most important processes determining the proper course of gestation and its physiological termination in cows is the adhesion of epithelial cells allowing for direct contact of maternal and foetal parts of the placenta. Throughout pregnancy, placental cells are under strict hormonal control, which among others regulates the concentration and activity of specific proteins participating in the extracellular matrix remodelling of foetal membranes. The aim of the study was to evaluate the influence of progesterone and prostaglandin F on the adhesion of epithelial cells at early-mid pregnancy in cows. Additionally, the impact of selected hormones on anti-adhesive properties of decorin was evaluated. Caruncular epithelial cells were isolated from healthy cows during pregnancy, immediately after slaughter. Primary cell cultures derived from the 2nd and 4th month of gestation were used in the experiments. The viability of cells was assessed by MTT assay. The adhesion of cells to fibronectin was measured spectrophotometrically. The activity of metalloproteinases was confirmed by the metalloproteinase assay. Progesterone (10–5 and 10–7 mol/L) and prostaglandin F (10–4, 10–5 and 10–7 mol/L) increased the viability of bovine caruncular epithelial cells in the 2nd month of pregnancy. The treatment with prostaglandin F significantly reduced the number of adherent cells from the 2nd month of gestation at the doses of 10–4 and 10–5 mol/L. Both progesterone and prostaglandin F were shown to have an effect of decorin resulting in both a decrease in metalloproteinase activity and an increase in adhesion of cells to fibronectin.  相似文献   
6.
Lactobacillus rhamnosus GG (LGG) is a well‐established probiotic strain. The beneficial properties of this strain are partially dependent on its prolonged residence in the gastrointestinal tract, and are likely influenced by its adhesion to the intestinal mucosa. The pilin SpaC subunit, located within the Spa pili structure, is the most well studied LGG adhesion factor. However, the binding epitopes of SpaC remain largely unknown. The aim of this study was to evaluate the binding properties of SpaC to the carbohydrate moieties of intestinal glycoconjugates using a recombinant SpaC protein. In a competitive enzyme‐linked immunosorbent assay, SpaC binding was markedly reduced by addition of purified mucin and the mucin oligosaccharide fraction. Histochemical staining revealed that the binding of SpaC was drastically reduced by periodic acid treatment. Moreover, in the surface plasmon resonance‐based Biacore assay, SpaC bound strongly to the carbohydrate moieties containing β‐galactoside at the non‐reducing terminus of glycolipids. We here provide the first demonstration that SpaC binds to the oligosaccharide chains of mucins, and that the carbohydrate moieties containing β‐galactoside at the non‐reducing termini of glycoconjugates play a crucial role in this binding. Our results demonstrate the importance of carbohydrates of SpaC for mucus interactions.  相似文献   
7.
动物腹腔手术后粘连的成因及防制概述   总被引:1,自引:0,他引:1  
就术后粘连发生的诱因、发生机理进行了阐述,并结合动物粘连模型的试验研究结果及临床研究结果,对预防腹腔手术后粘连的药物和方法进行了综述。  相似文献   
8.

采用间接ELISA法研究菌浓度、孵育时间、温度、pH、阳离子及碳源等因子对嗜水气单胞菌(Aeromonas hydrophila)黏附鳗鲡(Anguilla anguilla)表皮黏液的影响。结果表明, 改良后的间接ELISA法的检测灵敏度约为9.92×104 CFU, 细菌的黏附量随菌浓度的升高而逐渐增大并符合饱和黏附动力学方程: y=0.135ln(x)-0.936(R2= 0.986); 嗜水气单胞菌黏附鳗鲡表皮黏液的最佳条件为: 温度20~28℃, pH 6.2~6.6, NaClMgCl2质量浓度分别为15~25 g/L3 g/L, 孵育时间为150 min。碳源对嗜水气单胞菌的黏附作用有不同程度的影响, 葡萄糖和麦芽糖能显著提高嗜水气单胞菌的黏附量(P<0. 05), 果糖则显著降低嗜水气单胞菌的黏附量(P<0. 05)。以上结果说明, 嗜水气单胞菌对鳗鲡表皮黏液具有较强的黏附作用, 且其黏附作用具有可控性。

  相似文献   
9.
益生菌在水产动物肠道内黏附机制的研究进展   总被引:3,自引:0,他引:3  
潘晓东  吴天星  陈斌 《水产科学》2005,24(11):53-54
双歧杆菌、乳酸杆菌、芽孢杆菌、酵母是益生菌制剂中最常用、最具代表性的菌种。大多数商品化的益生菌制剂是将这些菌以单一的或复合的形式,混合在粉料载体中或添加些蛋白性原料,然后将益生菌制剂直接混合在饲料中添加或制成混合液直接加入水体。各种菌通过肠道并在肠道壁黏附发挥益生作用,能否黏附定植于肠道壁是益生菌作用的前提,也是菌种筛选的重要指标。已有的研究表明,各类微生物的黏附是非特异性的,即与菌体的结构有关,菌体能接近肠道上皮细胞,菌体的特殊配体进一步与宿主细胞相应的受体之间特异性结合,既黏附素一受体学说。  相似文献   
10.
蚯蚓非光滑体表试样的法向土壤粘附特性   总被引:3,自引:0,他引:3  
以赤子爱胜蚓(Eisenia foetida)为研究对象,利用微粘附力测试系统,通过单因素试验探讨蚯蚓非光滑体表的法向粘附力随含水量的变化规律;通过正交多项式设计法寻求正压力与卸载速度对蚯蚓非光滑体表法向粘附力的影响,建立了回归方程。试验结果表明,蚯蚓体表试样的法向粘附力随含水量的增加呈抛物线趋势增加,与钢试样相比,最大减粘率达到44%;正压力对法向粘附力呈二次效应关系,卸载速度对法向粘附力呈一次效应,随正压力和卸载速度的增加粘附力增加。本研究可为生物非光滑表面仿生研究以及揭示仿生耦合机制提供基础数据。  相似文献   
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