ABSTRACT
Objective To explore the interaction of streptococcus suis serotype 2 recombinant suilysin ( SLY ) with platelets, and provide the theoretical basis for clinic treatment of patients infected with S.suis.Methods The nickel column affinity chromatography was used to purify the recombinant SLY.The hemolytic acivity was identified by optical density before the platelets aggregation induced by a SLY was detected by a platelet aggregometer or electron microscope and the effect of aspirin on platelets aggregation was analyzed.The impact of wild type 05ZYH33 and sly-deficient mutant strainΔSLY on platelets of mice was compared to predict the interaction of the SLY with platelets in vivo.Results and Conclusion Hemolytic activity of recombinant SLY was 2000 hemolytic units( HU) and platelets aggregation was induced at 1 μg/ml.The aggregation can be inhibited by aspirin in 5 mmol/L.SLY can also increase the volume and reduce the amount of platelets in mice.
ABSTRACT
Snake venom toxins have been reportedly used as a rich source of a number of proteins of biotechnological interest due to their wide range of effects on haemostasis. These effects vary greatly: coagulant, anticoagulant, platelet-activating, anti-platelet, fibrinolytic and hemorrhagic, in either enzymatic or non-enzymatic pathways. Agkistrodon venom contains a variety of proteins that possess antiplatelet activities. This study presents recent development in our laboratory to produce and purify antiplatelet proteins derived from Agkistrodon blomhoffi ussuriensiss nake venom. Different matrices of HPLC (size exclusion, ion exchange and affinity chromatography) were employed for purifying the proteins and their biological and biochemical properties were characterized by SDSPAGE, 2-D electrophoresis, platelet aggregation assay and enzyme activity assay.A purified disintegrin was a single chain glycoprotein with Mr of 13 kDа and рІ 4.7, whereas PLA2 had Mr of 14 kDa and pI of 4.17. A dose-dependent activity curve analysis shows that the platelet aggregation inhibitory activity of disintegrin and PLA2 in the rabbit plateletrich plasma were ID50 of 0.25 μМ and 0.65 μМ, respectively. Bioprocesses to produce and purify active antiplatelet agents from A. blomhoffi ussuriensis venom have been developed, using modern liquid chromatography matrices. Ongoing work to optimize large-scale production process is being undertaken.
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Objective To investigate the changes and clinical significance of platelets aggregation rate of patients with coronary heart disease before and after percutaneous transluminal coronary stenting Methods There are 13 patients underwent coronary angiography and 20 patients underwent percutaneous transluminal coronary stenting Their blood samples were taken from the coronary sinus and coronary artery before and after interventional therapy Results The level of platelets aggregation rate in percutaneous transluminal coronary stenting group was higher after interventional therapy ( P
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In the control rabbits 6 h after smoke inhalation injury, the pulmonary vascular permeability and the circulating platelet aggregation percentage increased distinctly, pathological changes of trachea and lung were marked. In the other 2 groups, ginsenosides (25 mg/kg, iv) or ketoprofen (12 mg/kg, iv) were given 15 min after injury, 6 h after treatment, although both drugs decreased, the aggregation percentage of circulating platelets, only ginsenosides did alleviate the augmented pulmonary vascular permeabil ity and the pathological changes of trachea and lung. In the similar model of smoke inhalation injury in rats, ginsensi-des increased the PGI2 level in arterial blood and reduced the ratio of TXA2/ PGI2 1 h after treatment.
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S AIM To study the protective effects of trigonella foenum graecum(TFGs) on acute cerebral ischemia. METHODS Acute incomplete ischemia was induced by ligaturing bilateral carotid arterise and cutting heads in mice, the survival time and asthmatic time were observed; the coagulation time was measured by sheet glass method,and the blood viscosity was also assayed; the platelet aggregation induced by collagen were studied by turbdimetry in vitro . RESULTS TFGs prolonged survival time, coagulation time and asthmatic time significantly and inhibited platelet aggregation ratio in rabbit,and decreased the blood viscosity. CONCLUSION TFGs has the protective effects on acute cerebral ischemia.