Congenital deficiency of blood clotting factors II, VII, IX, and X

Activated clotting factors in factor IX concentrates.

The precise quantitation of activated factors in human factor IX concentrates has been accomplished with the use of recently developed, specific assays for factors IXa, Xa, and thrombin. The assay for factor IXa, which measures the initial rate of 3H-factor-X activation, was shown to be specific for factor IXa in the concentrates. Activated factor IX concentrates contained 1.0-2.3 microgram/ml ...

Activation of human factor VII by activated factors IX and X.

Factor VII clotting activity increases about five-fold when blood is clotted in glass. Prior studies suggested that this results from activation induced by activated factor IX (IXa). However, in purified systems containing phospholipid and calcium, activated factor X (Xa) is known to activate factor VII rapidly. Therefore, we studied activation of factor VII by IXa and X, in systems using purif...

Nomenclature for blood clotting factors.

Clinical manifestations, management, and molecular genetics in congenital factor VII deficiency: the International Registry on Congenital Factor VII Deficiency (IRF7)

Factor VII deficiency is a rare bleeding disorder in which premature death may occur from severe bleeding. Up to now, our scientific knowledge on factor VII deficiency has been mainly based on reporting of single cases and groups of patients from confined geographical areas.1-3 To improve our insight and understanding of the epidemiology and the heterogeneity of factor VII deficiency through de...

Factor II, VII, IX and X concentrations in patients receiving long term warfarin.

Using standard one stage clotting assays the concentrations of factors II, VII, IX and X were determined in 37 patients stabilised on warfarin for between three months and 17 years. Contrary to popular belief, the concentrations were not equally depressed, with factor X the lowest, factor II at intermediate value, factors VII and IX the highest. Some 71% of the variance of the British corrected...