Thrombosis research
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Thrombosis research · Apr 1995
Case ReportsFibrinogen Guarenas I: partial characterization of a new dysfibrinogenemia with an altered rate of fibrinopeptide release and an impaired polymerization.
A congenitally abnormal fibrinogen was isolated from the blood of a young woman with a severe bleeding diathesis. Coagulation tests showed a prolonged Thrombin and Reptilase time partially corrected by Ca2+. Polymerization of thrombin induced preformed fibrin monomers was severely impaired. ⋯ The father has a minor fibrinopeptide release defect suggesting the presence of two populations of fibrinogen. This study supports the idea that the fibrinogen isolated from the propositus has two defects inherited as separate genetic traits. This fibrinogen has been named Fibrinogen Guarenas I.
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Thrombosis research · Apr 1995
Endotoxin-induced pulmonary vascular injury is mainly mediated by activated neutrophils in rats.
Acute respiratory failure is a common complication in patients with disseminated intravascular coagulation associated with sepsis. To elucidate the role of coagulation abnormalities in acute lung injury in sepsis, we investigated the effect of anticoagulants on the pulmonary vascular injury in rat induced by lipopolysaccharide (LPS). When administered intravenously, LPS (5 mg/kg body weight) significantly increased the accumulation of 111indium-labeled neutrophils in lung 30 min after administration. ⋯ Neither heparin alone, heparin plus antithrombin III, or dansyl-Glu-Gly-Arg-chloromethyl ketone-treated factor Xa, a selective inhibitor of thrombin generation, prevented LPS-induced vascular injury 6 hours after LPS administration, whereas these substances significantly inhibited the increase in serum FDP (E) at that time. LPS-induced pulmonary vascular injury was significantly attenuated in rats with methotrexate-induced leukocytopenia or treated with ONO-5046, a potent granulocyte elastase inhibitor, although ONO-5046 did not inhibit the LPS-induced increase in serum FDP (E). Thus, activated leukocytes play a more important role than coagulation abnormalities in the pathogenesis of LPS-induced pulmonary vascular injury in an experimental rat model of endotoxemia.
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Thrombosis research · Mar 1995
Thrombolysis with tissue plasminogen activator (tPA) is temperature dependent.
Thrombolysis with tissue plasminogen activator (tPA) and hypothermia are two potential treatment modalities for acute ischemic stroke. Many investigators are studying these modalities both in the laboratory and in clinical trials. Because these modalities each appear to show benefit in animal models, there is considerable interest in studying combined therapy with both thrombolysis and hypothermia. ⋯ Rijken et al studied plasminogen activation with tissue plasminogen activator (tPA), urokinase and streptokinase at extremely low temperatures. They found less plasminogen activation and fibrinogen degradation at 25 degrees C compared to 37 degrees C, but negligible differences at 10 degrees C, 0 degrees C and -8 degrees C. To our knowledge, there is no data studying the fibrinolytic activity of tissue plasminogen activator (tPA) at temperature ranges between 25-37 degrees C which is the range of temperatures used clinically for therapeutic purposes.(ABSTRACT TRUNCATED AT 250 WORDS)
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Thrombosis research · Dec 1994
Comparative StudyScreening of dysfibrinogenaemia using the fibrinogen function versus antigen concentration ratio.
The diagnosis of inherited and acquired dysfibrinogenaemia is usually suspected in patients with otherwise unexplained prolonged thrombin time or other tests with thrombin-like enzymes (1). Confirmation of the diagnosis requires discordant results from the investigation of functional fibrinogen and its antigen concentration. However, the issue of the difference between the two results required to confirm dysfibrinogenaemia has rarely been addressed. ⋯ In that study plasma from healthy blood donors was investigated using the Clauss method and radial immunodiffusion. We applied this approach to randomly selected patients at the time of admission to a University Hospital Department. Since fibrinogen is one of the major acute phase proteins, the determination of the C-reactive protein (CRP) was included for comparison.