Background: Inhibitory antibody to exogenous Factor VIII (FVIII) is a major complication of hemophilia treatment. This study was conducted to determine the prevalence of inhibitor antibody directed against FVIII.Methods: From May 2010 to May 2011, 52 patients with severe hemophilia A admitted in Amirkola Children’s Hospital were evaluated. Those who had abnormal mixing study, antibody against F...

In vivo prothrombin activation is thought to occur via a factor Xa/factor V-dependent mechanism. We investigated whether human venous endothelial cells (EC) could be induced to express a prothrombin activator. EC treated with lipopolysaccharide (LPS) or interleukin-1 activated prothrombin in the absence of exogenous factors Xa and V. This activity resided in the membrane fraction of EC and was ...

In the mouse leukemic monocyte cell line RAW 264.7, the vacuolar-type (H(+))-ATPase (V-ATPase) inhibitors bafilomycin A1 and concanamycin A induced nitric oxide (NO) production through the expression of inducible nitric-oxide synthase mRNA and its protein and decreased cell growth and survival as determined by 3-(4,5-dimethyl(thiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Bafilomyci...

Background Plasma Tissue Factor Pathway Inhibitor (TFPI) circulates bound to factor V (fV) and Protein S (PS). Estrogen therapy decreases plasma TFPI and PS. TFPI, fV, and PS circulate within platelets, and are released upon activation to modulate thrombus formation. Objective Identify factors affecting the concentrations of plasma and platelet TFPI, fV, and PS. Methods Blood samples were o...

Background & Aims: Preeclampsia is one of the complications of pregnancy and a major cause of maternal mortality. Since, hypercoagulation is one of the risk factors, defined polymorphisms of V and II coagulation factors (G1691A and G20210A) may increase the risk of the disease. Methods: This investigation was performed on blood samp...

Severe factor V (FV) deficiency is associated with mild to severe bleeding diathesis, but many patients with FV levels lower than 1% bleed less than anticipated. We used calibrated automated thrombography to screen patients with severe FV deficiency for protective procoagulant defects. Thrombin generation in FV-deficient plasma was only measurable at high tissue factor concentrations. Upon reco...

In a report reading like a fascinating detective story, Vincent and colleagues crack the mysterious case of east Texas bleeding disorder. They show that affected individuals have a mutation in exon 13 of the coagulation F5 gene that causes increased expression of an alternatively spliced transcript, which encodes a previously unrecognized factor V (FV) isoform they call FV-short. This FV isofor...

Studies were performed on a FrenchCanadian family afflicted with a bleeding disorder exhibiting an autosomal dominant inheritance pattern and a severe bleeding diathesis after trauma. Clinical laboratory coagulation tests were unimpressive; the only persistent abnormalities include mild thrombocytopenia and moderately reduced Factor V clotting activities. Some individuals had prolonged Stypven ...

Studies were performed on a French-Canadian family afflicted with a bleeding disorder exhibiting an autosomal dominant inheritance pattern and a severe bleeding diathesis after trauma. Clinical laboratory coagulation tests were unimpressive; the only persistent abnormalities include mild thrombocytopenia and moderately reduced Factor V clotting activities. Some individuals had prolonged Stypven...