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O D RATNOFF

Publications and source records attributed to O D RATNOFF.

At least 37 records · Page 2Linked to original sources
PubMed1962

The enhancement of chloroform-induced plasma proteolytic activity by epsilon aminocaproic acid.

The proteolytic activity in chloroform-treated plasma euglobulins has been attributed to plasmin. Plasmin can digest both casein and fibrin. Epsilon aminocaproic acid, which inhibits the activation of plasminogen, the precursor of plasmin, by streptokinase, urokinase, and tissue activators enhanced the development of casein hydrolytic activity in a mixture of chloroform and plasma euglobulins. Fibrinolytic activity was also enhanced, but this was evident only if the epsilon aminocaproic acid was removed from the chloroform-treated euglobulins prior to assay. The reasons for the paradoxical enhancement of chloroform-induced casein hydrolysis by euglobulins containing epsilon aminocaproic acid are unclear. However, studies of optimal pH, heat stability, and the effect of ionic strength on the activation of the precursor of this proteolytic enzyme do not differentiate it from plasminogen.

Amino Acids↗
PubMed1960

Hageman trait.

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Blood Coagulation↗
PubMed1958

Studies on the activation of a proesterase associated with partially purified first component of human complement.

It has been found that under a wide range of physico-chemical conditions a positive correlation exists between the rate of disappearance of hemolytically active, partially purified first component of human complement and the rate of activation of an esterase hydrolyzing N-acetyl-L-tyrosine ethyl ester. Both reactions follow the kinetic equation for second order autocatalysis, with an apparent energy of activation of 31,000 calories per mol. They occur optimally at pH 7.3-7.7 and are inhibited by ionic strengths greater than 0.15, by 5 x 10(5)M ethylenediaminetetraacetic acid, and by a heat-labile serum inhibitor which appears unrelated to any component of complement. The activation of first component to esterase resembles closely the activation of trypsinogen to trypsin. Partially purified first component, containing plasminogen, may also be activated to esterase by addition of streptokinase. The significance of these data with respect to the postulated existence of first component as a proesterase and its possible role in complement-"fixation" is discussed.

Complement System Proteins↗