Chemical Footprinting Reveals Conformational Changes Following Activation of Factor XI.

Coagulation factor XI is activated by thrombin or factor XIIa resulting in a conformational change that converts the catalytic domain into its active form and exposing exosites for factor IX on the apple domains. Although crystal structures of the zymogen factor XI and the catalytic domain of the protease are available, the structure of the apple domains and hence the interactions with the catalytic domain in factor XIa are unknown. We now used chemical footprinting to identify lysine residue containing regions that undergo a conformational change following activation of factor XI.

Stimulation of thrombin- and plasmin-mediated activation of thrombin-activatable fibrinolysis inhibitor by anionic molecules.

Background: Thrombin-activatable fibrinolysis inhibitor (TAFI) is a proenzyme that, once activated, attenuates fibrinolysis by removing C-terminal lysine residues from partially degraded fibrin. TAFI can be activated by thrombin or plasmin via a cleavage at Arg92 that removes the activation peptide from the enzyme, TAFIa. Thrombomodulin enhances thrombin-mediated TAFI activation and glycosaminoglycans enhance plasmin-mediated TAFI activation.

Use of an absorbable embolization material for reversible portal vein embolization in an experimental model.

Background: Portal vein embolization (PVE) is used to increase future remnant liver size in patients requiring major hepatic resection. PVE using permanent embolization, however, predisposes to complications and excludes the use of PVE in living donor liver transplantation. In the present study, an absorbable embolization material containing fibrin glue and different concentrations of the fibrinolysis inhibitor aprotinin was used in an experimental animal model.

Structure-function relationships in thrombin-activatable fibrinolysis inhibitor.

Thrombin-activatable fibrinolysis inhibitor (TAFI) is an important regulator in the balance of coagulation and fibrinolysis. TAFI is a metallocarboxypeptidase that circulates in plasma as zymogen. Activated TAFI (TAFIa) cleaves C-terminal lysine or arginine residues from peptide substrates.

Selective modulation of thrombin-activatable fibrinolysis inhibitor (TAFI) activation by thrombin or the thrombin-thrombomodulin complex using TAFI-derived peptides.

Background: Thrombin-activatable fibrinolysis inhibitor (TAFI) is a risk factor for coronary heart disease. TAFI is proteolytically activated by thrombin, the thrombin-thrombomodulin complex and plasmin. Once active, it dampens fibrinolysis and inflammation.