Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P00750 (PLA)
 16,800 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

It has been suggested that growth hormone (GH) plays a role in the regulation of Factor VIII-von Willebrand factor complex and other parameters associated with haemostasis and vascular integrity. However, limited information is available on these features in GH-deficient patients. We therefore examined, in a double-blind, placebo-controlled crossover design, the effects of 4 months' replacement therapy with biosynthetic human GH in 22 GH-deficient adults on circulating haemostatic parameters and capillary fragility. A non-significant increase in the plasma levels of von Willebrand factor antigen (p = 0.09), Factor VIII antigen (p = 0.6), fibrinogen (p = 0.4) and fibronectin (p = 0.2) was observed at the end of the GH treatment period along with a non-significant decrease in tissue-type plasminogen activator (p = 0.2). Capillary fragility tended to decrease during GH therapy (p = 0.2). All variables remained within the reference range following both the placebo and the GH treatment period. It is concluded that GH-deficient patients display normal levels of the haemostasis parameters recorded, and that 4 months of GH therapy in a conventional replacement dose does not significantly affect these values.
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PMID:Growth hormone (GH) therapy in GH-deficient patients, the plasma factor VIII-von Willebrand factor complex, and capillary fragility. A double-blind, placebo-controlled crossover study. 211 72

The effects of early coronary recanalization on the plasma levels of two procoagulant acute phase proteins, the fastacting plasminogen activator inhibitor and von Willebrand factor, were investigated in 24 patients with myocardial infarction receiving intravenous recombinant tissue-type plasminogen activator (rt-PA) within 6 h of the onset of symptoms. Coronary angiography was performed before and 90 min after the start of rt-PA infusion. Continuous electrocardiographic recordings and 4 h plasma creatine kinase MB isoenzyme (CK MB) were performed over the first 24 h. Plasma plasminogen activator inhibitor activity, von Willebrand factor and C-reactive protein were measured before rt-PA infusion, daily for the first 3 days and after 90 days. In the entire group, plasminogen activator inhibitor activity peaked at 24 h (day 1), representing a significant increase over values at all other times (p = 0.03). von Willebrand factor was higher in the first 2 days of infarction compared with after 90 days (p = 0.001). C-reactive protein peaked on day 2, with an eightfold increase over values on admission (p = 0.001). In the 16 patients with a patent infarct-related artery at 90 min, infarct size estimated by integrated 24 h CK MB, time for ST segment elevation to decrease to half-maximum and peak C-reactive protein were reduced significantly by more than twofold compared with values in the 8 patients with an occluded artery at 90 min. The patients with early recanalization also had lower plasminogen activator inhibitor activity on day 2 (p = 0.05) and day 3 (p = 0.02) and lower 0 to 72 h averaged von Willebrand factor (p = 0.01). Thus, early coronary recanalization curtails the response of plasminogen activator inhibitor activity and von Willebrand factor to myocardial infarction, most likely by reducing the extent of ischemia and necrosis and the consequent acute phase reaction. By blunting the early postinfarction procoagulant state, prompt recanalization may reduce the risk of thromboembolic complications in the first days after myocardial infarction.
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PMID:Early coronary reperfusion blunts the procoagulant response of plasminogen activator inhibitor-1 and von Willebrand factor in acute myocardial infarction. 212 6

Endotoxemia was evoked by bolus injection of Escherichia coli endotoxin (2 ng/kg body weight) in six healthy subjects to investigate the early kinetics of cytokine release in relation to the development of clinical and hematologic abnormalities frequently seen in gram-negative septicemia. The plasma concentration of tumor necrosis factor (TNF) increased markedly after 30 to 45 minutes, and reached a maximal level after 60 to 90 minutes. In each volunteer, the initial increase of plasma interleukin 6 (IL-6) concentrations occurred 15 minutes after the initial TNF increase, and maximal IL-6 concentrations were reached at 120 to 150 minutes. A transient increase in body temperature and pulse rate occurred simultaneously with the initial TNF and IL-6 increases, whereas a significant decrease in blood pressure occurred after 120 minutes. These changes were proportional to the changes in TNF and IL-6 concentrations. Coagulation activation, as assessed by a rise of prothrombin fragments and thrombin-antithrombin III complexes, was noted after 120 minutes, in the absence of activation of the contact system. A two- to sixfold increase in the concentrations of tissue plasminogen activator (t-PA) and von Willebrand factor antigen indicated endothelial cell activation. This increase started at 120 and 90 minutes, respectively. The release of t-PA coincided with activation of the fibrinolytic pathway, as measured by plasmin-alpha 2-antiplasmin complexes. The fibrinolytic activity of t-PA was subsequently offset by release of plasminogen activator inhibitor, observed 150 minutes after the endotoxin injection, and reaching a peak at 240 minutes. No complement activation was detected. These results show that in humans endotoxin induces an early, rapidly counteracted fibrinolytic response, and a more long-lasting activation of thrombin by a mechanism other than contact system activation. In addition, our data suggest that endotoxin-induced leukopenia and endothelial cell activation are mediated by TNF.
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PMID:Experimental endotoxemia in humans: analysis of cytokine release and coagulation, fibrinolytic, and complement pathways. 212 34

Stimulation of the isolated perfused rat hindleg vascular bed with various concentrations of endothelin-1 or endothelin-3 resulted in the acute release of tissue-type plasminogen activator (t-PA) and of von Willebrand factor (vWF). The release of both endothelial cell products required the presence of extracellular calcium; the release of vWF by endothelin was instantly inhibited by disodium EDTA. The calcium antagonists nifedipine, diltiazem and verapamil partially inhibited endothelin-induced t-PA release, but had no effect on endothelin-induced vWF release.
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PMID:Endothelin-1 and -3 induce the release of tissue-type plasminogen activator and von Willebrand factor from endothelial cells. 212 63

Plasma fibrinolytic factors were measured in 14 patients with chronic idiopathic thrombocytopenic purpura (ITP), in 5 patients with chronic central thrombocytopenia and in 16 healthy volunteers. The von Willebrand factor (vWF), tissue-type plasminogen activator (t-PA) and D-dimer (DD) antigens were found to be significantly higher in both patient groups than in the control group. No difference appeared in euglobulin fibrinolytic activity and plasminogen activator inhibitor activity. The increases in both t-PA and vWF suggest the occurrence of an endothelial cell stimulation, associated with the reduction of circulating platelet number. The correlation of increased DD and t-PA levels during ITP can be the proof of a fibrinolysis activation and suggest an antifibrinolytic role of platelets at physiological concentrations. These results can justify antifibrinolytic therapy in bleeding thrombocytopenic patients.
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PMID:Increased plasma tissue-type plasminogen activator levels in patients with chronic thrombocytopenia. 212 64

Plasma levels of thrombin-antithrombin III complex (TAT), plasmin-alpha 2-plasmin inhibitor complex (PAP), von Willebrand factor antigen (vWF:Ag) plasminogen activator antigen (PA) and plasminogen activator inhibitor-1 antigen (PAI-1), were determined in 110 patients with arterial thromboembolic diseases within 4 weeks after attack (Th; 41 cases with myocardial infarction and 69 with cerebral infarction), 67 patients with various types of carcinoma (Ca; 31 cases without metastasis and 36 with metastasis) and 50 age-matched healthy individuals (Co). The following results were obtained: 1) Mean plasma levels of TAT, PAP, vWF:Ag, PA and PAI-1 were significantly higher in Th than Co. 2) Mean plasma levels of TAT, PA and PAI-1 were significantly higher in Ca than Co regardless of metastasis but those of PAP and vWF:Ag were significantly higher only in Ca with metastasis than Co. 3) Significant relationship was observed between plasma levels of TAT and PAP both in Th and Ca. 4) Significant relationship was also observed between plasma levels of TAT and vWF:Ag, PA or PAI-1 in Th, but not in Ca. It is suggested from these results that the coagulopathies observed in these patients result from the activation of intravascular blood coagulation and fibrinolysis, and that vascular endothelial cell damage may play an important role in the activation in Th.
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PMID:Studies on the pathogenesis of coagulopathy in patients with arterial thromboembolism and malignancy. 214 28

The influence of invasive investigations on parameters of hemostasis and fibrinolysis is generally unknown, although this has consequences for the design of prospective studies on the association between those parameters and regression or progression of atherosclerosis. We therefore determined hemostatic and fibrinolytic factors in 12 patients who were admitted to the hospital for coronary angiography (CAG; n = 5) or percutaneous transluminal coronary angioplasty (PTCA; n = 7). Blood samples were drawn under basal circumstances on the day before, the day of and the day after CAG or PTCA. Significant changes occur in the concentrations of platelets and white blood cells, hematocrit (Ht), von Willebrand factor antigen (vWF:ag), antithrombin III-activity (AT III-ag), antithrombin III-antigen (AT III-ant), fibrinogen, plasminogen, alpha2-antiplasmin (alpha2-AP), histidine-rich glycoprotein (HRG), and plasminogen activator inhibitor (PAI)-activity. Mean values of beta-thromboglobulin, platelet factor 4, factor VIII:C, tissue-type plasminogen activator activity (t-PA act) and euglobulin clot lysis time (ECLT) do not differ significantly. After correction for Ht, no significant differences exist between the day before and the day of the procedure; but on the day after CAG and PTCA significant differences occur in white blood cells, factor VIII:C, AT III-ag, alpha2-AP and PAI-act. It is concluded that principally blood samples for investigations on fibrinolysis may be taken on the day before or the day of CAG or PTCA without a loss of quality, if the values are corrected for Ht. Samples taken on the day after the procedure are not useful for such purposes.
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PMID:The influence of coronary angiography and angioplasty on parameters of hemostasis and fibrinolysis. 214 44

The effects of activation of plasminogen by streptokinase and tissue-type-plasminogen activator on platelet activation and the membrane glycoproteins (GPs) that mediate platelet adhesion and aggregation are not yet fully defined. To clarify effects on platelets during activation of plasminogen in vitro, we used monoclonal antibodies (MoAbs), flow cytometry, and platelets surface-labeled with 125I to characterize changes in receptors for fibrinogen (GPIIb-IIIa), von Willebrand factor (GPIb), and collagen (GPIa-IIa). Activation of plasminogen in plasma with pharmacologic concentrations of plasminogen activators did not degrade GPIIb-IIIa or GPIb, and caused only a modest decrease in GPIa. In washed platelets GPIIb-IIIa was extensively degraded by plasmin at 37 degrees C in the absence of exogenous Ca2+, conditions that destabilize the IIb-IIIa complex. Degradation of GPIb in washed platelets displayed a similar although less-marked dependence on temperature and the absence of Ca2+. The binding of activation-specific MoAbs did not increase during activation of plasminogen in plasma. We conclude that during pharmacologic fibrinolysis, reported inhibition of platelet function in plasma is not due to degradation of platelet-adhesive receptors. In addition, platelet activation observed during thrombolytic therapy does not appear to be a direct consequence of plasminogen activation.
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PMID:Dependence of plasmin-mediated degradation of platelet adhesive receptors on temperature and Ca2+. 216 24

We have studied the dose-response effects of dietary supplementation with n-3 polyunsaturated fatty acids (n-3 PUFA's) on lipids and haemostasis. Ten healthy males were each given 1.3 g, 4 g or 9 g of n-3 PUFA's daily for 6-week periods. Bleeding time, HDL-cholesterol and plasminogen activator inhibitor increased with the dose of n-3 PUFA. Plasma fibrinogen and triglyceride levels were reduced in a dose-dependent fashion. After ingestion of 1.3 g of n-3 PUFA's plasma fibrinogen decreased from 9 to 7 mumol/l and HDL-cholesterol increased from 1.2 to 1.3 mmol/l. The bleeding time was prolonged from 5 to 6.5 min while triglyceride levels decreased from 1.2 to 0.9 mmol/l after ingestion of 4 g of n-3 PUFA's. Dietary supplementation with the highest daily dose (9 g) reduced plasma levels of triglycerides, fibrinogen and von Willebrand factor, while bleeding time, plasminogen activator antigen, plasminogen activator inhibitor and the ratio of HDL-cholesterol to total cholesterol increased.
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PMID:Dose-response studies on the effect of n-3 polyunsaturated fatty acids on lipids and haemostasis. 202 34

The accumulated body of evidence suggests a role for a cell-mediated immune mechanism in the pathogenesis of scleroderma vascular disease. The most likely target for immune injury is either the endothelial cell itself or components of its basal lamina, which include type IV collagen and laminin. Whatever the specific target, the net effect is persistently altered endothelial cell dysfunction. However, the molecular basis for the development of endothelial cell injury is not known. Direct investigations of perivascular infiltrating cells have not been possible yet; published studies have focused on the in vitro effects of peripheral blood mononuclear cells and selected cytokines on endothelial cell behavior and function. Understanding the multiple cellular effects of various cytokines on endothelial cells may further the knowledge of the vascular disease. Systematic study of interactions between endothelial cells and cells of the immune system may provide the molecular basis for vascular injury and open yet unidentified avenues for therapy. Furthermore, monitoring parameters of endothelial cell injury may help to define the disease in an earlier and more meaningful fashion. Circulating levels of EC products such as von Willebrand factor, plasminogen activator, and prostacyclin/thromboxane metabolites may permit a precise definition of disease activity and assist the clinician in monitoring responses to therapy.
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PMID:Vascular disease in scleroderma. Endothelial T lymphocyte-fibroblast interactions. 240 11


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