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AIM:To investigate the effect of platelet inhibitor from Agkistrodon halys venom (AHV-PI) on lipopolysaccharide (LPS) induced human umbilical vein endothelial cells (HUVECs) injury in vitro, and to explore its mechanism. METHODS:Cultured HUVECs were induced inflammatory injury by LPS (1 mg/L). The experiment was divided into blank control group, LPS group, AHV-PI group and AHV-PI+LPS group. The viability of HUVECs was measured by MTT assay. The morphological changes of HUVECs were observed under inverted microscope. The optimum concentration of AHV-PI at 5 mg/L was selected. Flow cytometry was used to detect apoptosis of HUVECs. Immunohistochemical method was used to observe the expression of tissue type plasminogen activator (t-PA) and plasminogen activator indhibitor-1 (PAI-1) of HUVECs. ELISA was used to detect the concentrations of intercellular adhesion molecule-1 (ICAM-1) and tissue factor (TF) in the supernatant. The activation and translocation of NF-κB subunit p65 were observed by immunofluorescence staining. RESULTS:The HUVECs were spindle shaped, the ratio of length to width was increased, the cells were fibroblast-like, and granular substance appeared in the cytoplasm in LPS group. The viability and morphological changes of HUVECs were not significantly affected as treated with AHV-PI at concentration of 0~5 mg/L, but the viability of HUVECs induced by LPS was inhibited and the morphological changes were alleviated. Compared with the blank control group, the levels of TF and ICAM-1 in the supernatant increased, and the expression of t-PA and PAI-1 in the HUVECs was decreased in LPS group. Compared with the LPS group, the contents of TF and ICAM-1 in the supernatant were significantly decreased, the expression of t-PA and PAI-1 in the HUVECs was increased and the expression of nucleus NF-κB p65 was decreased in AHV-PI+LPS group (P<0.05). CONCLUSION:AHV-PI reduces HUVECs damage. The protective mechanism is related to the inhibition of cytokine secretion and NF-κB activation.  相似文献   
63.
Many snake venoms contain complex mixtures of pharmacologically important molecules, some of which show potential therapeutic value in the treatment of cancer and other human disorders. In this review, we mainly reports the effects of snake venom active components, such as disintegrins and lectins in paralyzing cancer cells, blocking on cell migration, interaction with integrins, inhibition of tumor dissemination and angiogenesis. The advanced researches on the snake venom's apoptosis-inducing components on tumors are also introduced.  相似文献   
64.
寄生蜂毒液和卵巢蛋白在寄生过程中起着重要作用,蛋白成分和性质的研究日益深入。本文主要通过SDS-聚丙烯酰胺凝胶电泳(SDS-PAGE)试验,分析了腰带长体茧蜂毒液和卵巢蛋白的分子量组成。结果表明,腰带长体茧蜂毒液蛋白图谱显示约有7条蛋白带介于43~100kDa之间,含量较高的三条带为97kDa、64kDa、45kDa;卵巢蛋白图谱显示约有12条蛋白带,位于30~200kDa之间,含量较高的两条带为39kDa、43kDa。并对毒液和卵巢的生物学功能进行了探讨。  相似文献   
65.
蛇岛是我国唯一一个以蛇岛蝮蛇(Agkistrodon shedaoensis)为主要保护对象的国家级自然保护区,具有重要的科研和生态保护价值,但外来物种入侵已经对该岛生态环境及生物多样性造成严重威胁。本文对蛇岛外来物种的入侵现状进行了野外实地调查,并对其入侵途径、危害特点进行了详细分析。同时,为有效保护蛇岛蝮蛇及蛇岛的生物多样性,提出了控制外来物种入侵的具体建议和对策。  相似文献   
66.
REASON FOR PERFORMING STUDY: Matrix metalloproteinases (MMPs)-2 and -9 activities have been found elevated in synovial fluid from various joint diseases in man. However, in the horse few data are available. OBJECTIVES: To explore the clinical significance of MMP-2 and -9 activities in synovial fluid of horses with different forms of joint diseases. METHODS: Gelatin zymography and MMP-2 and -9 immunocapture activity assays were applied on synovial fluids from control joints and joints with aseptic joint disease (AJD) and septic arthritis (SA). Additionally, MMP-2 and -9 activities were measured in samples from SA to monitor the disease process. RESULTS: Zymographic analysis revealed that samples from AJD and SA contained significantly increased latent MMP-2 activity compared to controls. Samples from SA showed significantly increased monomeric latent MMP-9 activity compared with all other affected joints and controls. Trace amounts of MMP-9 activity, due to the active and dimer form, were detected in samples from SA; however, these bands were absent in samples from AJD and controls. Using immunocapture activity assays, MMP-2 and -9 activities were found to be significantly elevated in joints from SA compared to controls and AJD samples. MMP-2 activity in samples from AJD was significantly increased compared to controls. Both MMP activities decreased in the joints from SA in the course of successful therapy. CONCLUSIONS: Data from zymographic analysis confirmed that MMP-2 and -9 were elevated in equine joint diseases. Immunocapture activity assays have been shown to be suitable for the quantitative determination of MMP-2 and -9 activities in synovial fluid of horses. Both MMP-2 and -9 activities seem to be useful to indicate SA, and MMP-2 activity might be a suitable marker for AJD. POTENTIAL RELEVANCE: These findings encourage the potential use of MMP-2 and -9 as additional aids to clinical investigation. Further work is required to validate the clinical significance of MMP activities in the progress of different joint diseases in horses.  相似文献   
67.
A rapid, qualitative blood test was developed to identify potential bleeders among dogs that are von Willebrand's disease suspects. The test, based on venom coagglutinin-induced agglutination of formalin-fixed washed platelets, was compared to the more lengthy electroimmunoassay for factor VIII-related antigen. The 2 tests were performed on plasma samples from 82 dogs, including 68 Doberman pinschers. The 39 plasma samples that were found to be "clinically normal" by the new test had factor VIII-related antigen concentrations ranging from 32% to 192% of that in a pool of normal canine plasma samples. Plasma samples from the 43 dogs that tested as "potential bleeders" by the new test had factor VIII-related antigen concentrations from 4% to 38%. All 43 "potential bleeders" were Doberman pinschers. Shortly after being evaluated by the new test, 46 of the dogs underwent invasive diagnostic, therapeutic, or cosmetic procedures. Excessive hemorrhage was encountered in 40% of the 25 dogs that tested as "potential bleeders. " In contrast, only 5% of the 21 dogs that tested as "clinically normal" exhibited abnormal bleeding.  相似文献   
68.
 电取蜂毒不利于蜜蜂群势发展和养蜂生产。电取蜂毒 3d 1次 ,连续 10次 ,可使蜂蜜减产 4 5 .6 4 %~4 9.90 % ,差异显著 (P <0 .0 5 ) ;蜂王浆产量平均降低 4 6 .17% ,差异极显著 (P <0 .0 1) ;移虫接受率平均降低31.0 5 % ,差异极显著 (P <0 .0 1) ;但对单台产浆量、饲料消耗量、蜂王有效产卵量等影响不大。连续取毒后 11d ,对蜜蜂群势的发展影响不大 ,而 2 3d后蜜蜂群势比对照组低 12 .87% ,35d后低 2 8.81% ,差异均极显著 (P <0 .0 1)。  相似文献   
69.
王连翠  张玉翠 《安徽农业科学》2006,34(13):3031-3031,3033
用不同浓度的GA3和KT对蛇瓜种子进行了处理,结果表明:GA3可以提高蛇瓜种子的发芽率、发芽势、发芽指数,对其幼苗生长有明显的促进作用,并可极大地提高其活力指数;而KT也可以提高种子的发芽率、发芽势,但作用不显著。同时KT对幼苗的生长有一定的抑制作用,但可以增加幼苗的地上部和根的鲜重。  相似文献   
70.
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