Murine lymphoid cells respond rapidly to bacterial lipopolysaccharide or antigen-antibody complexes to initiate or accelerate the blood coagulation pathways. The monocyte or macrophage has been identified as the cellular source, although lymphocyte collaboration is required for the rapid induction of the procoagulant response. This procoagulant activity is identified in the present study as a d...

Vitamin K is required for the posttranslational formation of gamma-carboxyglutamyl residues in a number of plasma clotting factors. Interference with vitamin K action results in the appearance of abnormal (des-gamma-carboxy) forms of prothrombin in human plasma. Vitamin K-sufficient patients with primary hepatocellular carcinoma also secrete significant quantities of abnormal prothrombin; this ...

Highly purified dicoumarol-induced bovine prothrombin, which does not bind calcium ions and has no prothrombin activity, has been structurally compared with normal prothrombin. Quantitative amino acid and carbohydrate analysis gave identical results for both prothrombins, as did analysis of the NHz-terminal and the COOH-terminal amino acids and molecular weight determination with the sodium dod...

Human prothrombin was acetylated to produce a modified prothrombin that upon activation by platelet-bound prothrombinase generates a form of thrombin that does not activate platelets but retains its amidolytic activity on a chromogenic peptide substrate. If normal prothrombin is used in such an assay, the thrombin that is generated activates the platelets in a feedback manner, accelerating the ...

BACKGROUND AND OBJECTIVES To evaluate the association between unexplained or gestational-hypertension-associated fetal growth restriction (FGR) and factor V Leiden, prothrombin A20210 mutations, and methylenetetrahydrofolate reductase (MTHFR) TT 677 genotype. DESIGN AND METHODS Sixty-one women with a previous history of FGR and 93 parous women with uneventful pregnancies from the same ethnic ...

OBJECTIVE To find out whether changes in the daily prothrombin time are of prognostic importance in patients with paracetamol induced fulminant hepatic failure. DESIGN Retrospective study. SETTING The Liver Unit, King's College Hospital, London. PATIENTS 150 Consecutive patients with paracetamol induced fulminant hepatic failure admitted between October 1986 and February 1989. MAIN OUTC...

Vitamin K deficiency or administration of vitamin K antagonists results in the biosynthesis of abnormal des-gamma-carboxy forms of the vitamin K-dependent proteins. Monoclonal antibody H-11 binds several vitamin K-dependent proteins at a determinant that includes the first two residues of gamma-carboxyglutamic acid. Antibody H-11 binds fully carboxylated prothrombin and protein C in the presenc...

In this study, we test the hypothesis that prothrombin levels may modulate activated protein C (APC) anticoagulant activity. Prothrombin in purified systems or plasma dramatically inhibited the ability of APC to inactivate factor Va and to anticoagulate plasma. This was not due solely to competition for binding to the membrane surface, as prothrombin also inhibited factor Va inactivation by APC...

In this study, we test the hypothesis that prothrombin levels may modulate activated protein C (APC) anticoagulant activity. Prothrombin in purified systems or plasma dramatically inhibited the ability of APC to inactivate factor Va and to anticoagulate plasma. This was not due solely to competition for binding to the membrane surface, as prothrombin also inhibited factor Va inactivation by APC...

Thrombin is a serine protease that is generated by proteolytic cleavage of its precursor, prothrombin. We previously showed that thrombin proteolyses the microtubule-associated protein tau and that phosphorylation of tau inhibits this process. To characterize further the role of thrombin in the brain, we investigated prothrombin and thrombin expression in cultured brain cells and in brains of c...