Blood Group O (blood + group_o)

Distribution by Scientific Domains


Selected Abstracts


Variables influencing Platelet Function Analyzer-100TM closure times in healthy individuals

BRITISH JOURNAL OF HAEMATOLOGY, Issue 5 2005
Hannelore Haubelt
Summary We investigated the relationship between platelet function analyzer (PFA-100TM) closure times (CT) and bleeding time (BT), platelet aggregation (PA) induced by ADP, arachidonic acid, and collagen, blood cell counts, and von Willebrand factor (VWF) in 120 well-characterised healthy individuals. Pre-analytical and analytical conditions were standardised comprehensively. In a substantial number of cases the differences between duplicate measurements exceeded 15%. The reference range (5th and 95th percentiles) for CT with the collagen/epinephrine (CEPI) and the collagen/ADP (CADP) cartridge was 93,223 s and 64,117 s respectively. Re-examination of 11 individuals with CEPI-CT above the 95th percentile revealed considerable batch-to-batch variation of CEPI-CT. Males had significantly longer CADP than females (P = 0·002). CEPI and CADP-CT measured pm were significantly longer than corresponding values determined am (P = 0·003 and P < 0·0001 respectively). Blood group O was associated with greater CEPI and CADP-CT and lower VWF levels compared with non-O blood groups (P = 0·008, P = 0·0003 and P < 0·0001 respectively). Linear regression analysis revealed association between CEPI-CT, CADP-CT and VWF (P < 0·0001), but no relationship was found between CT and BT or between CT and PA. We conclude that VWF plasma levels modulate PFA-100TM CT to a greater extent than platelet function. Establishment of reliable reference ranges and careful standardisation of pre-analytical and analytical conditions is a prerequisite for obtaining reliable PFA-100TM results. Duplicate measurements are necessary. [source]


The Interleukin-1 RN Polymorphism and Helicobacter pylori Infection in the Development of Duodenal Ulcer

HELICOBACTER, Issue 6 2004
Ping-I Hsu
ABSTRACT Background., The host genetic factors that determine the clinical outcomes for Helicobacter pylori -infected individuals remain unclear. Aims., To elucidate the relations among interleukin-1 locus polymorphisms, and H. pylori infection in the development of duodenal ulcers. Materials and methods., In a case,control study involving 168 control subjects and 147 patients with duodenal ulcer, biallelic polymorphisms of two interleukin-1 loci, IL-1B,511 and IL-1B+3954, as well as the penta-allelic variable number of tandem repeats of interleukin-1 receptor antagonist IL-1RN, were genotyped, and the H. pylori states of controls and patients were examined. Results.,Helicobacter pylori infection, male gender and the carriage of IL-1RN*2 independently increased the risk of duodenal ulcer with odds ratios of 6.4 (95% confidence interval, 3.7,11.0), 1.9 (95% confidence interval, 1.1,3.4) and 2.7 (95% confidence interval, 1.1,6.8), respectively. Statistical analysis revealed an interaction between IL-1RN*2 and H. pylori infection with the duodenal ulcer risk conferred by the H. pylori infection substantially increased (odds ratios, 22.6; 95% confidence interval, 5.9,86.5) by the carriage of IL-1RN*2. In addition, a synergistic interaction between IL-1RN*2 and blood group O existed. The combined risk of H. pylori infection, the carriage of IL-1RN*2 and blood group O for duodenal ulcer was 27.5 (95% confidence interval, 3.1,243.6). Conclusions., This work is the first to verify IL-1RN*2 as an independent factor that governs the development of duodenal ulcers. Our data indicate that H. pylori infection and IL-1RN*2 synergistically determine susceptibility to duodenal ulcer. The blood group phenotype is possibly a crucial determinant for the outcome of the impact of an interleukin-1 locus polymorphism on H. pylori -infected individuals. [source]


Evidence of Immune Tolerance to Blood Group Antigens in a Case of ABO-Incompatible Pediatric Liver Transplantation

AMERICAN JOURNAL OF TRANSPLANTATION, Issue 9 2007
H. Ohdan
In a 12-year-old patient with blood group O, who had received a partial liver graft 10 years ago from his father with blood group A, the levels of anti-A-specific antibodies (Abs) were persistently undetectable after the transplantation, while the levels of anti-B-specific Abs gradually increased and attained a plateau. Peripheral blood mononuclear cells (PBMCs) from this patient were engrafted into NOD/SCID mouse in order to investigate the immune response to donor-type blood group antigens. Even after sensitization with blood group-A erythrocytes, no anti-A Abs were detected in the serum samples of the mouse that received PBMCs from the blood group-O recipient of group-A liver allograft, however, immunoglobulins specific for antigens other than the A antigens were produced. Thus, we provide a possible evidence of immune tolerance to blood group antigens in this ABO-incompatible pediatric liver transplantation. [source]


Transplantation of ABO Group A2 Kidneys from Living Donors into Group O and B Recipients,

AMERICAN JOURNAL OF TRANSPLANTATION, Issue 3 2001
John B. Sorensen
Fifteen blood group O and B recipients have been transplanted with kidneys from subtype A2 living donors since April 1992. ABO red cell grouping was performed by local licensed blood banks with A2 subtype determined using an anti-A1 lectin and, retrospectively, by a polymerase chain reaction (PCR)-based molecular method. All grafts functioned immediately and no patient has required dialysis. Three patients each experienced one reversible rejection episode. With the exception of one cardiac death at 9 months and one patient with profound toxicity to calcineurin inhibitors, all allografts continue to function normally. One donor, mistyped as a group A2 using lectin, was by PCR typing an A1O1 nonsecretor; the graft continues to function normally at 30 months. Transplantation of living donor A2 renal allografts into non-A recipients produces excellent long-term allograft survival and expands the potential living donor pool for nonblood group A recipients. [source]


Maternal IgG anti-A and anti-B titres predict outcome in ABO-incompatibility in the neonate

ACTA PAEDIATRICA, Issue 12 2009
Egil Bakkeheim
Abstract Aim:, To evaluate predictors for risk of severe hyperbilirubinaemia and kernicterus in ABO-incompatible neonates with emphasize on maternal IgG anti-A/-B titres. Methods:, Blood group O women in labour at Oslo University Hospital, Ullevål, were included in the years 2004,2006. Offspring with blood group A or B had direct antiglobulin test performed and IgG anti-A/-B levels measured in maternal plasma. Blood group A or B infants developing severe hyperbilirubinaemia, received in addition to phototherapy, immunoglobulin treatment and/or exchange transfusion (EXT). Results:, Of 253 neonates, 61.3% had blood group O, 29.6% blood group A and 9.1% blood group B. Twenty neonates with blood group A or B received at least one immunoglobulin treatment. In multivariate analysis, maternal antibody-titres were the only significant predictors for immunoglobulin treatment (p < 0.0001), EXTs (p < 0.05) and duration of phototherapy (p < 0.0001). The need for invasive treatment increased sharply for antibody titres ,512. Receiver operating characteristic analyses demonstrated that titres ,512 had a sensitivity of 90% and a specificity of 72% for predicting immunoglobulin treatment and thus severe hyperbilirubinaemia. Conclusion:, Maternal IgG anti-A/-B titres contribute to the prediction of risk of severe hyperbilirubinaemia in ABO-incompatible neonates, in addition to blood-grouping and direct antiglobulin-testing, especially following early discharge after delivery. [source]