Background: Hemophilia B is a bleeding disorder with a recessive X-linked inheritance pattern, in which the infected individuals have low levels of factor IX in their plasma. Affected individuals may have bleeding episodes after trauma or spontaneously considering the plasma level of factor IX. In order to prevent these episodes and to control bleeding, they should use coagulation factor concen...

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 ...

Factor IX deficiency was associated with a hemorrhagic disorder in a woman who previously had experienced postpartum hypotension resulting in Sheehan’s syndrome. There was no family history of Christmas disease, and other known causes of factor IX deficiency were excluded. Plasma levels of factor IX were partially corrected by therapy with thyroid hormones and completely restored to normal by t...

lmmunoassays with a monoclonal antibody (A-i ) detect a prevalent dimorphism in plasma coagulation factor IX. The antibody was shown to react with a dimorphic segment of the normal factor IX sequence as follows. First. A-i bound to isolated activation peptide (residues 146 through 180) prepared from activated factor IX from a normal plasma pool. Second, binding of recombinant factor lXs with A-...

Replacement therapy for hemophilia B (factor IX deficiency) using prothrombin complex concentrate (PCC) has been associated with serious complications of thromboembolic events and transmission of viral infections. Monoclonal antibody-purified factor IX (Mononine) provides a highly purified factor IX concentrate, while eliminating other vitamin K-dependent factors (II, VII, and X). Mononine was ...

Human coagulation factor XI (FXI) is a plasma serine protease composed of 2 identical 80-kd polypeptides connected by a disulfide bond. This dimeric structure is unique among blood coagulation enzymes. The hypothesis was tested that dimeric conformation is required for normal FXI function by generating a monomeric version of FXI (FXI/PKA4) and comparing it to wild-type FXI in assays requiring f...

We describe the synthesis of a haemoglobin (Hb) wrapped covalently by recombinant human serum albumin mutants [HSA(Y161H)] containing Mn(III) protoporphyrin IX (MnPP), the Hb-[HSA(Y161H)-MnPP]3 cluster, highlighting the formation of its O2-complex stable even in H2O2 solution.

Human coagulation factor XI (FXI) is a plasma serine protease composed of 2 identical 80-kd polypeptides connected by a disulfide bond. This dimeric structure is unique among blood coagulation enzymes. The hypothesis was tested that dimeric conformation is required for normal FXI function by generating a monomeric version of FXI (FXI/PKA4) and comparing it to wild-type FXI in assays requiring f...

The kinetics of the tissue factor-dependent activation of Factors IX and X have been studied in a bovine plasma system. Heat-defibrinated plasma, which lacks Factors VIII, V, and fibrinogen, was depleted of Factors IX and X by using specific antibodies coupled to Sepharose. Activation initiated by the addition of bovine brain thromboplastin was studied by adding back to the plasma radiolabeled ...