Metalloproteases from at least two Gram-negative organisms selectively hydrolyze the surface of human fixed washed platelets. The protease-treated platelets lose their ability to aggregate with bovine von Willebrand factor and human von Willebrand factor plus ristocetin. The present study reports the membrane glycoprotein alterations and loss of platelet function that occur after incubation of ...

The platelet glycoproteins (GPs) Ib, integrin alpha(2)beta(1), and GPVI are considered central to thrombus formation. Recently, their relative importance has been re-evaluated based on data from murine knockout models. To examine their relationship during human thrombus formation on collagen type I fibers at high shear (1000 s(-1)), we tested a novel antibody against GPVI, an immunoglobulin sin...

Type 2B von Willebrand disease (VWD2B) is caused by an abnormal von Willebrand factor (VWF) with increased affinity for the platelet receptor glycoprotein Ib-alpha (GPIb-alpha) that may result in moderate to severe thrombocytopenia. We evaluated the prevalence and clinical and molecular predictors of thrombocytopenia in a cohort of 67 VWD2B patients from 38 unrelated families characterized by V...

Platelet membrane glycoprotein Ib (GPIb) and the GPIIb-IIIa complex have central roles in the interaction of platelets with the plasma coagulation system, damaged vessel walls, and other platelets. We investigated the effects of thrombin on these glycoproteins. Monoclonal antibodies were used to assess platelet surface glycoproteins by flow cytometry, total platelet glycoprotein content by immu...

Platelet adhesion to vascular subendothelium under conditions of high shear stress is mediated by the platelet glycoprotein (GP) Ib-von Willebrand Factor (vWF) interaction. The aim of this study was to characterize the murine monoclonal antibodies (MoAbs) 27A10 and 28E6, both raised against purified GPIb. The MoAb 27A10 is a potent inhibitor of shear-induced platelet adhesion to collagen type I...

Hardware and software for a high-speed, pulsed-data-acquisition system are described. Data can be obtained via any device attachable to a VXI crate, GPIB controller, or directly via serial or parallel ports. Stepper motors controlled via serial port automate probe movement. LabVIEW and custom C11 modules are used to handle setup, data gathering and processing, and user interface. Experimental p...

The major part of the GARFIELD apparatus electronics are monitored and set up through a slow control system, which has been developed at LNL. A software package based on Lab View has been dedicated to the setting and control of 16 channels integrated Amplifiers and Constant Fraction Discriminators. GPIB controllers and GPIB-ENET interfaces have been used for the communication between the Person...

Ethernet, with its higher bandwidth and ubiquitous usage, seems a natural alternative to the market-leading GPIB instrument control bus for automating instruments. However, it’s not always an accurate conclusion. There are many factors to consider when determining which bus provides better performance. Most important are the bus bandwidth and latency, the device-side instrument control hardware...

The snake venom C-type lectin alboaggregin A (or 50-kd alboaggregin) from Trimeresurus albolabris was previously shown to be a platelet glycoprotein (GP) Ib agonist. However, investigations of the signal transduction induced in platelets showed patterns of tyrosine phosphorylation that were different from those of other GPIb agonists and suggested the presence of an additional receptor. In this...

Echicetin, a new protein isolated from Echis carinatus venom by reverse phase and ion exchange chromatography specifically inhibited agglutination of fixed platelets induced by several platelet glycoprotein Ib (GPIb) agonists, such as bovine von Willebrand factor (vWF), alboaggregins, and human vWF in the presence of botrocetin. Unlike alboaggregins, echicetin bound to GPIb but did not induce a...