The complement system is an essential component of host defense against pathogens. Previous research in our laboratory identified StcE, a metalloprotease secreted by Escherichia coli O157:H7 that cleaves the serpin C1 esterase inhibitor (C1-INH), a major regulator of the classical complement cascade. Analyses of StcE-treated C1-INH activity revealed that surprisingly, StcE enhanced the ability ...

UNLABELLED Essentials How the Alzheimer's disease (AD) peptide β-amyloid (Aβ) disrupts neuronal function in the disease is unclear. Factor (F) XII initiates blood clotting via FXI, and thrombosis has been implicated in AD. Aβ triggers FXII-dependent FXI and thrombin activation, evidence of which is seen in AD plasma. Aβ-triggered clotting could contribute to neuronal dysfunction in AD and be a ...

Exposure of bovine pulmonary-arterial endothelial cells to the oxidant lipid t-butyl hydroperoxide (t-Bu-OOH) increases cell-membrane-associated phospholipase A2 (PLA2) activity and stimulates arachidonic acid (AA) release. To test the hypothesis that a membrane-associated serine esterase plays an important role in activating PLA2, the present study was undertaken. In addition to increasing PLA...

BACKGROUND Classically, intrinsic coagulation proteins are thought to have a minor role in hemostasis. Recently, these proteins, especially FXII, were implicated as possible key players in the pathogenesis of arterial thrombosis. This study aims to determine the risks of arterial thrombosis conferred by increased activation of intrinsic coagulation proteins in young women and the effect of oral...

Hereditary angioedema (HAE) caused by C1-esterase inhibitor deficiency is an autosomal-dominant disease resulting from a mutation in the C1-inhibitor gene. HAE is characterized by recurrent attacks of intense, massive, localized subcutaneous edema involving the extremities, genitalia, face, or trunk, or submucosal edema of upper airway or bowels. These symptoms may be disabling, have a dramatic...

The in-vitro effects of Captopril an angiotensin converting enzyme inhibitor were studied on TAME-esterase, a component of the Kinin-Kallikrein system, induced contractions on rat aorta strips. Our results showed that contractile responses induced by TAME (EC50 6 x 10 M) were significantly attenuated when the aorta strips were pre-incubated with 1M Captopril (EC50 1.8 x10M). Based on our data w...

5. A Fe2+ ion-ethylenediaminetetra-acetic acid complex can catalyse the oxidative formation of an inhibitor from schradan. 6. A mechanism for the simultaneous oxidation of schradan and reduced triphosphopyridine nucleotide is suggested. 7. The requirements for the conversion of dimefox to an anti-esterase are the same as those for schradan, but the rate of esterase inhibition is much higher. Di...

Several properties of the cholinesterase from Phaseolus aureus Roxb. and of pectin (methyl) esterases from both Phaseolus aureus and Lycopersicon esculentum (L.) Mill. are contrasted. Cholinesterase activity is inhibited by all of the concentrations of NaCl tested, from 0.05 m to 0.9 m, a property which differs sharply from published data pertaining to pectin esterase. Although crude preparatio...

BACKGROUND Idiopathic non-histaminergic acquired angioedema (InH-AAE) is a rare disease for which there are no available laboratory parameters to clearly define the disorder. Therapy is often difficult and various treatment options have been proposed. In this paper, we have evaluated the most effective therapies for InH-AAE on the basis of current literature and report the therapeutic effect of...