Background: von Willebrand factor (VWF) is a multimeric glycoprotein critically involved in hemostasis, thrombosis, and inflammation. VWF function is regulated by its antigen levels, multimeric structures, and the state of enzymatic cleavage. Population studies in the past have focused almost exclusively on VWF antigen levels in cross-sectional study designs.
View Article and Find Full Text PDFBackground: The WHO recommends that pre-transfusion testing should include ABO/RhD grouping followed by screening for red blood cell (RBC) alloantibodies using the indirect antiglobulin test (IAT). However, in Uganda, current practice does not include RBC alloantibody screening.
Objective: To assess the utility of 'home-made' reagent RBCs in alloantibody screening.
Ethnic differences in blood group frequencies might result in clinically important mismatches for transfusions. Arab people represent a large population for which no comprehensive database of red cell genotypes is available and Kuwaitis are no exception. For instance, the Rh blood group is the most elaborate blood group system that shows a high degree of polymorphism among different ethnic groups, there has been little classification of RH alleles in Arab people.
View Article and Find Full Text PDFBackground: Hemorrhage causes significant morbidity and mortality in people aged <65 years. A lyophilized platelet-derived hemostatic agent (Thrombosomes) demonstrated hemostatic efficacy in animal models. We report the results of the first safety trial of autologous Thrombosomes given to normal subjects.
View Article and Find Full Text PDFFetal and neonatal alloimmune thrombocytopenia (FNAIT) and neonatal alloimmune neutropenia (NAN) are two rare complications of newborns caused by antibodies against paternal inherited antigens. Human platelet (HPA) and neutrophil antigens (HNA) are the common targets. Human leukocyte antigen (HLA) class I proteins are also expressed on platelets and neutrophils and anti-HLA antibodies have occasionally been implicated in these complications.
View Article and Find Full Text PDFPurpose: Rh antigens can provoke severe alloimmune reactions, particularly in high-risk transfusion contexts, such as sickle cell disease. Rh antigens are encoded by the paralogs, RHD and RHCE, located in one of the most complex genetic loci. Our goal was to characterize RH genetic variation in multi-ethnic cohorts, with the focus on detecting RH structural variation (SV).
View Article and Find Full Text PDFBackground: There has yet to be a comprehensive analysis of blood group antigen prevalence in Asian Americans and Native Americans. There may be ethnic differences in blood group frequencies that would result in clinically important mismatches through transfusion.
Study Design And Methods: Blood donors who self-identified as Asian or Native American were tested using a single-nucleotide polymorphism (SNP) DNA array (HEA BeadChip kit, Bioarray Solutions Ltd) that predicts expression of 38 human erythrocyte antigens (HEAs) and by serology for ABO, D, C, M, N, Jk(a) , and Jk(b) .
Background: The coagulation protein von Willebrand Factor (VWF) is known to be elevated in pregnancy. However, the timing and nature of changes in VWF and associated parameters throughout pregnancy are not well understood.
Objectives: To better understand the changes in VWF provoked by pregnancy, we studied VWF-associated parameters in samples collected over the course of healthy pregnancies.
Background: Sickle cell disease (SCD) patients have dissimilar red blood cell (RBC) phenotypes compared to the primarily Caucasian blood donor base due, in part, to underlying complex Rh and silenced Duffy expression. Gene array-based technology offers high-throughput antigen typing of blood donors and can identify patients with altered genotypes. The purpose of the study was to ascertain if RBC components drawn from predominantly Caucasian donors could provide highly antigen-matched products for molecularly typed SCD patients.
View Article and Find Full Text PDFGenetic factors appear to contribute to the severity and progression of diabetic retinopathy. We assessed the associations of the C807T and Glu505Lys variants of the glycoprotein Ia (alpha(2) integrin) subunit of the platelet/endothelial collagen receptor and risk of retinopathy in a population-based survey of 288 diabetic patients in one Swedish community. Neither variant was associated with retinopathy risk overall.
View Article and Find Full Text PDFThe inconsistent findings among association studies that have examined the relationship between factor XIIIA Val34Leu and thrombosis may be owing to (1) population differences in the prevalence of other risk factors that modify the association with Val34Leu, or (2) linkage disequilibrium with other functional factor XIIIA polymorphisms. We therefore performed genotyping for factor XIIIA Val34Leu, Tyr204Phe and Pro564Leu in a population-based study of myocardial infarction (MI) and ischaemic stroke among white women <45-years of age and 345 demographically similar controls, and examined potential interactions with other risk factors. The presence of the factor XIIIA Leu34 allele was associated with a slight decreased risk of MI [odds ratio (OR) = 0.
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