title: Sodium periodate modification of factor VIII procoagulant activity.
abstract: Chemical treatment of human factor VIII by sodium periodate resulted in increased levels of procoagulant activity when measured by the two-stage assay. Increased levels of factor-VIII activity were observed following periodate treatment of factor-VII concentrates and normal, haemophilic and von Willebrand's disease plasmas. However, sodium periodate treatment of haemophilic plasmas which were completely deficient in factor-VIII activity did not cause any reduction in the clotting times of two-stage assays. No increase in procoagulant activity following oxidation of factor VIII could be detected by the one-stage assay method. Gel filtration of factor-VIII concentrates before periodate treatment showed that the protein exhibiting factor-VIII activity had an apparent molecular weight in excess of 1 000 000, whilst after periodate treatment the apparent molecular weight was reduced to 690 000.
mesh_terms: D001777:Blood Coagulation / Q000187:drug effects*; D002850:Chromatography, Gel; D005169:Factor VIII / Q000032:analysis / Q000378:metabolism*; D006467:Hemophilia A / Q000097:blood; D006801:Humans; D010504:Periodic Acid / Q000494:pharmacology*; D013997:Time Factors
chemical_list: D010504:Periodic Acid; D005169:Factor VIII