What is Fitzgerald factor?
Fitzgerald factor (high molecular weight kininogen) is an agent in normal human plasma that corrects the impaired in vitro surface-mediated plasma reactions of blood coagulation, fibrinolysis, and kinin generation observed in Fitzgerald trait plasma.
What is the molecular weight range of high molecular weight kininogen and low molecular weight kininogen?
The two plasma kininogens, high molecular weight kininogen (120 kDa) and low molecular weight kininogen (70 kDa) are spliced variants of the kininogen gene.
What is Fletcher factor?
Prekallikrein (PK), also known as Fletcher factor, is an 85,000 Mr serine protease that complexes with high-molecular-weight kininogen. PK is the precursor of plasma kallikrein, which is a serine protease that activates kinins. PK is cleaved to produce kallikrein by activated Factor XII (Hageman factor).
Where is Kininogen found?
High molecular weight kininogen It is synthesized in endothelial cells and is produced mostly by the liver. It is also a precursor protein for bradykinin.
What is factor VII deficiency?
Factor VII (seven) deficiency is a disorder caused by a lack of a protein called factor VII in the blood. It leads to problems with blood clotting (coagulation). Blood clotting normally occurs when there is damage to a blood vessel.
What are Bradykinins and their function?
Bradykinin is a potent endothelium-dependent vasodilator and mild diuretic, which may cause a lowering of the blood pressure. It also causes contraction of non-vascular smooth muscle in the bronchus and gut, increases vascular permeability and is also involved in the mechanism of pain.
Which disease is known as Royal disease?
Hemophilia is sometimes referred to as “the royal disease,” because it affected the royal families of England, Germany, Russia and Spain in the 19th and 20th centuries.
Where is factor XII produced?
Coagulation Factor XII (Hageman factor, FXII) is produced and secreted by the liver. It is the product of a single gene that maps to chromosome 5 . The gene for Factor XII is 12kb and is composed of 13 introns and 14 exons .
What is factor XIII deficiency?
Factor XIII deficiency is a rare, genetic bleeding disorder characterized by deficiency of clotting factor XIII. Clotting factors are specialized proteins that are essential for the blood to clot properly.
What is factor11 deficiency?
Summary. Factor XI deficiency is a rare genetic bleeding disorder caused by reduced levels and insufficient activity of a blood protein called factor XI. Factor XI is a clotting factor.
What is kallikrein Kininogen?
Kallikreins (tissue and plasma kallikrein) are serine proteases that liberate kinins (BK and KD) from the kininogens, which are plasma proteins that are converted into vasoactive peptides. Prekallikrein is the precursor of plasma kallikrein.
What is high molecular weight kininogen (HMWK) deficiency?
High molecular weight kininogen (HMWK) deficiency is an autosomal recessive coagulation defect. It is known by a variety of names, including Fitzgerald trait, Flaujeac trait, and Williams trait. Patients with HWMK deficiency do not have a hemorrhagic tendency, but they exhibit abnormal surface-mediated activation of fibrinolysis.
How do you test for kininogen deficiency in patients on heparin?
Specific assay to test for deficiency uses high molecular weight kininogen deficient plasma mixed with patient plasma; a PTT is performed and is compared to a standard curve of high molecular weight kininogen vs. PTT Interference occurs in these assays if patient is on heparin, hirudin or argatroban, possibly danaparoid
What is the function of high molecular weight kininogen?
High molecular weight kininogen is a protein produced by the liver (with no inherent catalytic activity) that is involved in the early steps of the intrinsic coagulation pathway; it functions as a cofactor and binds with prekallikrein and factor XI to help facilitate their activation by factor XIIa