Performance Characteristics of DOAC-Remove for Neutralization of the Effects of Apixaban and Rivaroxaban in Lupus Anticoagulant Assays.

Objectives: This study established the performance characteristics of DOAC-Remove for neutralization of the effects of rivaroxaban and apixaban in lupus anticoagulant (LAC) testing.

Methods: Normal donor, LAC control, and patient samples were spiked with rivaroxaban or apixaban to simulate their effects on the dilute Russell's viper venom time (dRVVT), activated partial thromboplastin time (APTT), and dilute prothrombin time (dPT). Anti-Xa activity was measured after spiking and after DOAC-Remove neutralization.

Plasma thrombospondin-1 is increased during acute sickle cell vaso-occlusive events and associated with acute chest syndrome, hydroxyurea therapy, and lower hemolytic rates.

Platelets are activated in sickle cell disease (SCD), and particularly during vaso-occlusive episodes (VOE). Thrombospondin-1 (TSP1), a major secretory product of activated platelets, is increased in the circulation in VOE and binds to sickle red blood cells (RBC) promoting vascular adhesion. Thus, we hypothesized that TSP1 may represent a plasma biomarker of disease severity in SCD.

Impact of anemia on platelet response to clopidogrel in patients undergoing percutaneous coronary stenting.

High residual platelet reactivity (HRPR) on clopidogrel is a predictor of recurrent ischemic events in patients undergoing percutaneous coronary interventions (PCI). Significant intraindividual variability in platelet aggregation on repeat testing has been reported. To understand factors contributing to the variability in platelet aggregation testing, we examined clinical and laboratory elements linked to HRPR in 255 consecutive patients tested ≥12 hours after PCI using light transmission aggregometry (LTA) in response to adenosine diphosphate 5 μmol/L and VerifyNow P2Y12 assay (VNP2Y12; Accumetrics).

Hepatic function after genetically engineered pig liver transplantation in baboons.

Background: If "bridging" to allo-transplantation (Tx) is to be achieved by a pig liver xenograft, adequate hepatic function needs to be assured.

Methods: We have studied hepatic function in baboons after Tx of livers from alpha1,3-galactosyltransferase gene-knockout (GTKO, n=1) or GTKO pigs transgenic for CD46 (GTKO/CD46, n=5). Monitoring was by liver function tests and coagulation parameters.

Cryoprecipitate prepared from plasma frozen within 24 hours after phlebotomy contains acceptable levels of fibrinogen and VIIIC.

Background: As blood centers prepare fewer plasma products from female donors to avoid HLA antibodies, the standard starting material for cryoprecipitate (cryo), fresh-frozen plasma (FFP), might become increasingly scarce. A unit of cryo must contain at a minimum 80 IU of VIIIC and 150 mg of fibrinogen. Plasma frozen within 24 hours after phlebotomy (FP24) contains nearly equivalent levels of clotting factors as FFP at the time of thawing and, although not AABB/FDA approved for this purpose, might be a suitable starting material for cryo (cryo24) manufacture.

Immunomodulatory derivatives induce PU.1 down-regulation, myeloid maturation arrest, and neutropenia.

The immunomodulatory drugs (IMiDs) lenalidomide and pomalidomide yield high response rates in patients with multiple myeloma, but the use of IMiDs in multiple myeloma is associated with neutropenia and increased risk for venous thromboembolism (VTE) by mechanisms that are unknown. We show that IMiDs down-regulate PU.1, a key transcription factor involved in granulocyte differentiation in vitro and in patients treated with lenalidomide.

Factor VIII-pulsed dendritic cells reduce anti-factor VIII antibody formation in the hemophilia A mouse model.

Objective: Hemophilia inhibitor formation is a T-cell-dependent immune response to infused factor VIII (F.VIII). As immature dendritic cells (DCre) regulate immune response and promote tolerance, we evaluated F.

Intensive plasma exchange increases a disintegrin and metalloprotease with thrombospondin motifs-13 activity and reverses organ dysfunction in children with thrombocytopenia-associated multiple organ failure.

Background: Thrombocytopenia-associated multiple organ failure (TAMOF) is a poorly understood syndrome in critically ill children. A disintegrin and metalloprotease with thrombospondin motifs (ADAMTS-13), formerly known as von Willebrand factor (VWF) cleaving protease, is decreased in adults with VWF-mediated thrombotic microangiopathy, and intensive plasma exchange (PEx) both replenishes ADAMTS-13 and improves outcome in these patients.

Objectives: To determine whether: 1) critically ill children with TAMOF syndrome have decreased ADAMTS-13 activity, 2) ADAMTS-13 activity correlates with platelet counts and VWF antigen, 3) the autopsies from patients who died with reduced ADAMTS-13 activity have VWF-rich microthrombi, and 4) intensive PEx will restore ADAMTS-13 activity and facilitate organ failure resolution.

Coagulation factor levels in plasma frozen within 24 hours of phlebotomy over 5 days of storage at 1 to 6 degrees C.

Background: The use of plasma frozen within 24 hours after phlebotomy (FP24) is likely to increase as male donors become the predominant source of plasma products. This study was performed to investigate the levels of clotting factors in thawed plasma (TP) prepared from FP24 during 5 days of storage at 1 to 6 degrees C.

Study Design And Methods: Five units of A, B, and O and 3 units of AB FP24 were obtained from the local blood provider.

Extended coagulation profiles of healthy baboons and of baboons rejecting GT-KO pig heart grafts.

Introduction: Derangements of coagulation, e.g. thrombotic microangiopathy (TM) and disseminated intravascular coagulation (DIC), limit the success of pig-to-baboon organ transplantation.

von Willebrand's disease and psychotic disorders: co-segregation and genetic associations.

Objectives: To evaluate co-segregation and genetic associations between von Willebrand's disease (vWD) and psychotic disorders.

Methods: The study was initiated following ascertainment of a nuclear family in which four members were diagnosed with vWD and psychotic/mood disorders. As co-segregation was uncertain in the extended pedigree, we also investigated population-based linkage and association using polymorphisms of vWF, the gene conferring susceptibility to vWD.