Factor XII Deficiency
نویسنده
چکیده
Factor XII ia a single-chain beta-globulin serine protease with a molecular weight of 80,000 84,000 daltons and a plasma concentration of approximately 30 pg/mL. Proteolytic cleavage of factor XII is mediated by charged surfaces (glass, kaolin, cellite, dextran sulfate, endotoxin, urates, crude collagen, sulfatides), autoactivation, and kallikrein. Prekallikrein, factor XI, factor VII, plasminogen, and complement C1are proteolytically cleaved by activated factor XII (factor XIIa) into their active forms.
منابع مشابه
Characterization of factor XII Tenri, a rare CRM-negative factor XII deficiency.
Factor XII Tenri (Y34C), a rare cross-reacting material (CRM)-negative factor XII deficiency, was identified in a 71-yr-old Japanese woman with angina pectoris. In the patient's plasma, factor XII activity and antigen levels were only 1.6% and 5.0%, respectively, of those seen in a normal subject. Immunoblot analysis showed that the secreted factor XII Tenri existed not only as a monomer (76 kD...
متن کاملFactor XII gene alteration in Hageman trait detected by TaqI restriction enzyme.
A cDNA for coagulation factor XII has been used to investigate the presence of gene lesions and restriction fragment length polymorphisms in two brothers with Hageman trait and their family. A TaqI polymorphic fragment has been found in the two propositi and in 11 members of the paternal lineage. This polymorphism, absent in the normal population, is correlated with the reduction of factor XII ...
متن کاملCoagulation Factor XII Congenital Deficiency in Women with Recurrent Miscarriage
Factor XII (Hageman factor) is an important protease that plays a major role in the initiation of the intrinsic pathway of blood coagulation and fibrinolysis and kinin formation. It is still unclear whether factor XII deficiency causes any disorders during pregnancy. Because the main clinical feature in patients with factor XII deficiency is thrombosis rather than bleeding, low dose aspirin wou...
متن کاملCase Report Essential thrombocytosis accompanied by coagulation factor XII deficiency: a case report
Essential thrombocytosis (ET) is a type of myeloproliferative neoplasm with clinical manifestations of thrombosis and hemorrhage, the mechanisms of which remains unclear. Some researches indicated that ET is mainly related to the defect of platelet function and the abnormality of coagulation mechanism. A few reports showed that ET accompanied by acquired hemophilia. However, no evidence of ET w...
متن کاملFactor XII (Hageman) Levels in Women with Recurrent Pregnancy Loss
OBJECTIVE To evaluate factor XII levels in women with recurrent pregnancy loss (RPL) in a tertiary referral hospital. METHODS Women who were referred to our hospital for two consecutive abortions or three abortions in between 2007 and 2013 were included in this retrospective observational study. Women were further grouped according to factor XII levels, as <60% and ≥ 60%. RESULTS Mean facto...
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The performance of cardiopulmonary bypass (CPB) in the factor XII-deficient patient is challenging in that the normal method for monitoring anticoagulation is ineffective as a result of an impaired contact activation system. We report the case of a factor XII-deficient patient who underwent surgical revascularization on CPB. His factor XII level was replenished with fresh-frozen plasma immediat...
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