In Vivo Studies of Human Plasmin. Intravenous Injection in Dogs and Rabbits

The Fibrinolytic Activity of Streptokinase Activated Human Plasmin 1

“…It has recently been suggested that the intravenous injection of purified human plasminogen, which has been activated in vitro by SK, may prove useful as a clot dissolving agent in man (5 Similarly the present assay for streptokinase should be re-evaluated. The unit of streptokinase is defined as the smallest amount of SK, which in the presence of human plasminogen will produce lysis of a bovine clot in 10 minutes or less, and was conceived as representing the amount of kinase needed to rapidly activate sufficient human plasminogen to lyse a clot in the period noted (14).…”

“…When a clot made with human fibrinogen and thrombin was used, the procedure was similar to the Christensen method except for the substitution of human reagents in similar concentrations to the bovine reagents. In the fibrinolytic assay, the enzyme solution to be assayed is serially diluted with buffer, fol- 5 The commercial bovine thrombin preparations of Upjohn and Parke, Davis Table I is shown a comparison of crystalline trypsin and several plasmin preparations, against three types of substrates which are attacked by both enzymes, i.e., casein, synthetic basic amino acid esters, and fibrin. The conventional assay of fibrinolytic activity was carried out with a bovine fibrinogen-bovine thrombin clot.…”

Plate Coagulase and Fibrinolysin Tests for Staphylococci

“…The results of " coagulase " plates prepared with different combinations of fibrinogen, plasma, and sera, are set out in Table I (Cliffton and Cannamela, 1953;Lack and Wailling, 1954). Perhaps it is time that more attention was given to these enzymes.…”

“…It would be worth considering whether these strains are more likely to cause secondary haemorrhage or loss of grafts when contaminating operation sites. There is reason to believe that staphylococci activate or produce more than one protease (Cliffton and Cannamela, 1953;Lack and Wailling, 1954). Perhaps it is time that more attention was given to these enzymes.…”