OBJECTIVES Hereditary resistance to activated Protein C (Factor V Leiden) is the commonest genetic defect known to confer a predisposition to thrombosis. This study aims to determine the prevalence of activated protein C resistance (APCr) in Lagos, and to determine if any association exists between APCr and ABO, Rhesus blood types, and hemoglobin phenotypes. MATERIALS AND METHODS A functional...

In 1993, individuals with a hereditary predisposition to venous thromboembolism whose plasmas exhibited a poor response to activated protein C (APC) in an activated partial thromboplastin time assay were identified.1 The molecular basis for this laboratory phenotype of resistance to APC was a guanine to adenine mutation at nucleotide 1691 in the factor V gene.2 This results in the replacement o...

Hormone replacement therapy (HRT) has been shown to increase the relative risk of idiopathic venous thromboembolism (VTE) about threefold in several observational studies and one randomised controlled trial. Whether or not this relative risk is higher in women with underlying thrombophilia phenotypes, such as activated protein C (APC) resistance, is unknown. We therefore restudied the participa...

Factor V (FV) Leiden is the most common genetic defect found in persons of European descent with venous thromboembolism.1 The 1691G.A transition determines the R506Q substitution.2 This suppresses a cleavage site for activated protein C (APC) on FVa, resulting in resistance to APC in a functional coagulation-based assay.3 FV Leiden accounts for over 90% cases of APC resistance, but this phenome...

Inherited resistance to activated protein C (APC), which is caused by a single point mutation in the gene for factor V, is a common risk factor for thrombosis. In this study, the prevalence of APC resistance in 18 unrelated thrombosis-prone families with inherited protein S deficiency was investigated to determine its role as additional genetic risk factor for thrombosis. In addition, a detaile...

Constitutive beta-catenin/Tcf activity, the primary transforming events in colorectal carcinoma, occurs through induction of the Wnt pathway or APC gene mutations that cause familial adenomatous polyposis. Mice carrying Apc mutations in their germ line (ApcMin) develop intestinal adenomas. Here, the crossing of ApcMin with cyclin D1-/- mice reduced the intestinal tumor number in animals genetic...

We study the transport properties of a superconducting Nb film with a square lattice of artificial pinning centers (APCs) as a function of dc current, at a temperature close to the superconducting transition temperature of the film. We find that, at low dc currents, the differential resistance of the film shows the standard matching field anomaly, that is, the differential resistance has a loca...

OBJECTIVE An increased risk of bleeding is observed in patients receiving activated protein C (APC), which may be a limiting factor for the application of novel APC therapies. Since APC's therapeutic effects often require its cytoprotective activities on cells but not APC's anticoagulant activities, an agent that specifically antagonizes APC's anticoagulant effects but not its cytoprotective ef...

INTRODUCTION The etiology of preeclampsia is not fully established. A few studies have shown a relationship between natural coagulation inhibitors and preeclampsia. OBJECTIVES The purpose of this study was to investigate the status of natural coagulation inhibitors and active protein C resistance (APC-R) in preeclampsia. PATIENTS AND METHODS We studied 70 women with preeclampsia recruited c...