The coagulase-reacting factor (CRF) of human plasma has been purified, concentrated, and largely freed of prothrombin activity by Seitz filtration, absorbtion on hyflo-amphogel columns, controlled phosphate buffer elution, and fractional ammonium sulfate precipitation. The purified CRF preparations localized between the beta and the gamma globulin position on paper electrophoresis, and the prin...

Terbium was used as a probe of Ca2+-binding sites on the prothrombin-phospholipid complex. Stoichiometric titrations of prothrombin binding to phospholipid vesicles with either Tb3+ or Ca2+ showed that a minimum of 8 metal ions were needed for binding prothrombin to vesicles (3 Mn2+ + 5 Ca2+ for prothrombin or 8 Tb3+ for F-1). When Ca2+ alone was used, a total of about 11 metal ions were needed...

I describe a radioimmunoassay for human prothrombin, with use of a double-antibody technique. Antiserum raised in rabbits was absorbed with Al(OH)3 and heated to 56 degrees C for 30 min. 125I-labeled prothrombin retaining more than 90% of its biological activity was prepared by the iodine monochloride method. The mean concentration of prothrombin in plasma of 12 normal individuals was 100 +/- 2...

1. The urinary F1 activation peptide of prothrombin is the predominant protein incorporated into calcium oxalate crystals precipitated from human urine. The aim of this study was to examine the effect of pure urinary prothrombin F1 on calcium oxalate crystallization in human urine. 2. Urinary prothrombin F1 was purified from demineralized calcium oxalate crystals precipitated from human urine, ...

clinicians should be aware of new developments to familiarize themselves with pharmacokinetic and pharmacodynamic characteristics of new anticoagulant agents to appropriately and safely use them. for the moment, cardiologists and other clinicians also require to master currently available drugs, realizing the mechanism of action, side effects, and laboratory monitoring to measure their anticoag...

Vitamin K is a substrate for the enzyme catalyzing the carboxylation of specific glutamyl residues to gamma-carboxyglutamyl residues in hepatic precursors of a limited number of plasma proteins, including prothrombin. The gamma-carboxylation of these proteins can be blocked by the anticoagulant warfarin; and in the bovine and human, warfarin treatment results in the secretion of under-gamma-car...

A large family has been studied, 11 of whose members have half-normal plasma concentrations of biological prothrombin activity. The pattern of inheritance is autosomal. By use of a specific immunoassay, affected family members have been shown to possess normal quantities of immunoreactive prothrombin, whose immunologic properties seem identical with those of the normal zymogen. Prothrombin isol...

There are a multiplicity of tests for liver functions, each depending upon a particular function of the liver. There has been growing recognition that the response in prothrombin time to the administration of vitamin K is of aid in the evaluation of hepatic function. The procedures heretofore employed to estimate the prothrombin response have lacked uniformity and, as a consequence, conflicting...

A mutant prothrombin, designated prothrombin Tokushima, was purified from plasma of a proband with 12% of normal plasma clotting activity and 42% of normal prothrombin antigen. The purified preparation gave a single band with the same mobility as that of "prothrombin" by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). The factor Xa-catalyzed proteolysis of prothrombin Toku...