EC Number   |
General Information |
Reference |
|---|
   3.4.21.27 | malfunction |
a deficiency in FXI (hemophilia C) results in a more benign bleeding phenotype compared with a deficiency in either FVIII (hemophilia A) or FIX (hemophilia B). Most hemophilia C cases involve Ashkenazi Jews and result from either of 2 mutations in the FXI gene (E117X and F283L). Greater than 180 mutations are present but in lesser frequency. FXI deficiency also arises from acquired inhibitors that neutralize its activity, these patients may not respond well to FXI replacement therapy. Bleeding in those with hemophilia C is rarely spontaneous, it tends to occur in response to surgery or trauma, and especially in tissue prone to fibrinolysis (the urinary track or oral cavity). Prolonged activated partial thromboplastin time due to FXI deficiency |
707308 |
| 3.4.21.27 | malfunction |
activated partial thromboplastin time is abnormal in all cases with severe or moderate FXI deficiency. FXI deficiency is not an absolute contraindication to neuraxial anesthesia |
707134 |
| 3.4.21.27 | malfunction |
addition of murine FXI to human FXI deficient plasma rescues the prolonged activated partial thromboplastin time, but with a slightly reduced activity compared with the human protein. FXI-/- mice are healthy, fertile, and phenotypically indistinguishable from wild-type animals. Mating between heterozygous FXI+/- mice follows the expected Mendelian ratio arguing against an association of FXI deficiency and increased risk of abortion. Plasma from FXI null mice show a severely prolonged activated partial thromboplastin time compared with wild-type animals. Bleeding times in adult FXI-/- mice are indistinguishable from wild-type animals, suggesting that FXI does not significantly contribute to fibrin formation. Formation of thrombi is severely defective in FXI-/- mice. Both fibrin deposition and platelet accumulation are reduced in FXI null mice compared with wild-type. FXI deficiency increases survival and reduces leukocyte infiltration and coagulopathy |
709722 |
| 3.4.21.27 | malfunction |
congenital FXI deficiency is associated with a variable, mild to moderate bleeding disorder. Severe deficiency is prevalent in people of Jewish ancestry. The severe mutation Glu117Stop encodes a truncated protein, and homozygotes lack plasma FXI antigen. The more subtle missense mutation Phe283Leu causes a defect in FXI dimer formation. Most cases of FXI deficiency are associated with low plasma levels of FXI protein. Deficiency or inhibition of FXI interferes with platelet accumulation in growing thrombi. A4 domain mutations associated with FXI deficiency interfere with dimerization. FXI-deficient plasma exhibits a prolonged activated partial thromboplastin clotting time |
707856 |
| 3.4.21.27 | malfunction |
enzyme deficiency results in bleeding diathesis referred to as hemophilia C |
732897 |
| 3.4.21.27 | malfunction |
factor XI deficiency can lead to delayed clot formation and decreased thrombin generation |
731773 |
| 3.4.21.27 | malfunction |
FXI deficiency is a rare inherited coagulation disorder characterized by infrequent spontaneous bleeding, but increased risk of hemorrhagic complications especially after trauma or surgery |
707148 |
| 3.4.21.27 | malfunction |
FXI deficient humans suffer from mild hemorrhage (hemophilia C), which is characterized by trauma or soft tissue-related hemorrhage, primarily involving tissues with high fibrinolytic activity. Bleeding severity in FXI deficiency is not associated with FXI plasma levels. Addition of murine FXI to human FXI deficient plasma rescues the prolonged activated partial thromboplastin time, but with a slightly reduced activity compared with the human protein |
709722 |
| 3.4.21.27 | malfunction |
FXI-null mice are healthy, and their reproduction follows the expected mendelian ratios without impaired fecundity. FXI-null mice are protected against oxidative iron chloride-induced carotid artery thrombosis and infusion of human FXI reverses this protection. Thrombus formation in FXI-null mice is also reduced in response to laser injury of arterioles in the cremaster muscle. FXI deletion is also effective in preserving carotid artery blood flow in response to compression injury |
707308 |
| 3.4.21.27 | malfunction |
mice lacking FIX, FXI, or FXII on a background of low tissue factor expression have a severe bleeding disorder but are viable. Superimposing FIX or FXI deficiency on the low tissue factor background results in death in utero from bleeding |
707856 |
