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    Assay of thrombolytic ('fibrinolytic') mixtures intended for therapeutic use.
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    The occasional occurrence of spontaneous fibrinolysis following major surgical procedures resulting in altered blood coagulation and bleeding has been noted with increasing interest. Numerous investigations recently reviewed by Astrup,3Albrechtsen,1Cooper,6and Cohen and Warren5have established that normal human blood contains an inactive proteolytic globulin termed plasminogen (profibrinolysin) (Fig 1). In the presence of certain activating substances in the blood, tissues, urine, or of bacterial origin, eg, streptokinase, staphylokinase, this globulin is converted to the active enzyme plasmin (fibrinolysin). This enzyme is capable of hydrolyzing the internal peptide bonds of the fibrin in the blood clot or other proteins containing structural sites suitable for activation by plasmin.12Free plasmin in the blood is neutralized by various inhibitors (antiplasmin).17Similarly, inhibitors of plasminogen activation are also known to exist.5 A significant observation by many surgeons has been the presence of excessive oozing in patients
    Fibrinolysin
    Staphylokinase
    Proteolytic enzymes
    SummaryA method for preparation and isolation of plasmin from purified human plasminogen after activation with streptokinase is presented. The product is water soluble, stable in the frozen state and produced no toxic manifestations in the dog after intravenous infusion of 1 mg/kg.
    Fibrinolysin
    Isolation
    Citations (17)
    We have shown that streptokinase (SK) is capable of building up thrombi in vivo on the blood-superfused collagen strips in extracorporal circulation of anaesthetized cats. The thrombogenic effects of SK appeared in all animals, irrespectively of whether SK was administered as intravenous bolus injections or infusions at doses comparable to those used for the treatment of patients with acute myocardial infarction. The thrombogenic phase of SK lasted up to 1.5 h and was followed by expected thrombolytic phase. Both phases were mediated by generation of plasmin. Inhibition of cyclooxygenase by aspirin or nitric oxide synthase by NG-nitro-L-arginine did not prevent SK from being thrombogenic. Also nitric oxide donor-SIN-1 did not remove the formation of thrombi by SK. The only effective treatment consisted of complementing the SK therapy with exogenous prostacyclin-like activity (e.g. iloprost). Prostacyclin not only abolishes thrombogenesis by SK but it also intensifies its thrombolytic action.
    Iloprost
    Fibrinolytic agent
    Citations (0)
    Caprolactone, valerolactone, and butyrolactone inhibit proteolytic and fibrinolytic activities of human plasmin. In very low concentrations, they also inhibit activation of plasminogen through plasmin-streptokinase activator and human urokinase. The degree of inhibitory potency depends upon the number of carbon atoms in the lactone.
    Fibrinolysin
    alpha-2-Macroglobulin
    Cleavage (geology)
    Thrombolytic agents, capable of dissolving fresh thrombi or emboli, are usually activators of plasminogen (profibrinolysin), plasmin (fibrinolysin), or plasmin-activator mixtures. Streptokinase, urokinase, and other plasminogen activators have been used as thrombolytic agents with encouraging results. The question whether plasmin or a plasminogen activator is the better thrombolytic agent may be answered when preparations of greater purity are tested. Accurate methods for standardizing these drugs have not yet been devised. While commercially available thrombolytic agents have been used in thrombophlebitis and other thromboembolic disorders with seemingly good results, further experimental and clinical evaluation is needed to determine the therapeutic usefulness of these agents.
    Fibrinolysin
    Fibrinolytic agent
    Thrombolytic drug
    The fibrinolytic properties of the preparations of plasmin (Pm), mixture of plasminogen and streptokinase (Pg+Sk), miniplasmin (m-Pm) and fibrinolysin have been investigated on the models of rabbit's hyphema. The action of preparations of Pm and Pg+Sk had approximately equal therapeutic index--the total destruction of clots proceeded for 12.0 days, that was 6.6 days less than in the control group. The therapeutic effect for m-Pm was 3.6 days. The dose of preparation of m-Pm, necessary for total destruction of clots, was 15-20% greater than for the same dose of Pg+Sk. The preparation of fibrinolysin, used in the same quantities of proteolytic activity, as Pg and m-Pg, (16 caseinolytic units per 1 injection) had no therapeutic effect.
    Fibrinolysin
    Therapeutic index
    Therapeutic effect
    Hyphema
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