There are three major types of VWD disease. Type 1, the most frequent form, is characterized by a partial quantitative deficiency in von Willebrand factor (VWF). Type 2 is a qualitative deficiency, and Type 3 is a virtually complete deficiency. Type 2 VWD is divided into four subtypes. Type 2A includes variants with decreased platelet adhesion caused by a selective deficiency in high-molecular ...

Platelet activating factor (PAF-ACETHER or PAF) and precursors of platelet activating factor were investigated in 26 patients with acute Crohn's disease and in 10 healthy controls. Platelet activating factor, lyso platelet activating factor, and alkyl acyl glycerophosphocholine, were determined in colonic mucosal biopsies in patients with acute Crohn's disease, during prednisolone therapy, and ...

Three patients with thrombotic thrombocytopenic purpura (TTP) were treated by infusion of normal plasma with dramatic responses. The plasmas collected from these patients during relapse induced in vitro aggregation of washed platelets from both normal donors and the patients during remission. The platelet aggregating factor was not dialyzable or adsorbable by Al(OH)3 and was not inactivated by ...

A test for platelet antibodies based on the inhibition of migration of platelets from a capillary tube is described. The technique is simple and is capable of detecting antibodies directed against HL-A antigens and the platelet-specific antigen, Pl-A1. Inhibitory activity was detected in sera from two of seven patients with idiopathic thrombocytopenic purpura. The platelet migration inhibition ...

Human platelet factor V has been isolated using either a monoclonal or polyclonal antibody directed against human plasma factor V. The largest peptide observed upon sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis of purified human platelet factor V comigrates with purified human plasma factor V. However. a significant portion of the isolated protein is represented ...

BACKGROUND Platelets are routinely stored in plasma for 5 days at an average temperature of 22°C. In the present study, the shelf life of random donor platelets was extended by storing for 7 days with and without additive solution at temperatures of 22°C, 18°C, and 16°C. METHODS Random donor platelets were stored in 100% plasma and 20%/80% platelet additive solution. The data were compared us...

The interaction of Factor Xa and Factor Va at the platelet surface was investigated by direct, simultaneous binding measurements of both proteins to platelets and by immunochemical and kinetic techniques. Binding measurements of 125I-Factor Xa and 131I-Factor Va to unstimulated platelets indicate that the amount of Factor Xa bound is proportional to the amount of Factor Va bound. At saturating ...