Human platelet concentrates stored at 22#{176}C for transfusion purposes progressively lose their in vitro sensitivity to single aggregating agents such as adenosine diphosphate (ADP). It is known that very small amounts of epinephrine. collagen. or arachidonic acid can markedly enhance the aggregation of platelets in fresh platelet-rich plasmas in response to concentrations of ADP that do not ...

In an ongoing study of the changes that occur in platelet concentrates during storage, we investigated two 28-26-Kd proteins designated SP-1 and SP-2, respectively, which increase markedly during blood-bank storage of platelet concentrates at room temperature. Formation of SP-1 and SP-2 was inhibited by storage at 4 degrees C as well as by treatment of the concentrates with leupeptin, N-ethylma...

Platelet-rich fibrin (PRF) belongs to a new generation of platelet concentrates geared to simplified preparation without biochemical blood handling. In this initial article, we describe the conceptual and technical evolution from fibrin glues to platelet concentrates. This retrospective analysis is necessary for the understanding of fibrin technologies and the evaluation of the biochemical prop...

While platelet concentrates are stored at room temperature, lactic and other acids are produced and the pH decreases as the buffering capacity of the plasma is exhausted. Platelet viability will be compromised if the pH decreases to pH 6.0 and below. Similarly, a pH decrease can be produced also by bacterial contamination if the organisms produce acid as an end product. Thus the determination o...

conclusions both l-prp and l-prf could be used to effectively promote the healing of articular cartilage defects of the knee. results mean macroscopic scores of the treated defects were higher than the controls at all sampling times with significant differences (p < 0.05) observed between l-prf treated and control defects (10.13 vs. 8.37) and l-prp treated and control defects (10 vs. 8.5) at 4 ...

Multiple causes (pseudothrombocytopenia, hemodilution, increased consumption, decreased production, increased sequestration, and immune-mediated destruction of platelets) alone or in combination make thrombocytopenia very common in intensive care unit (ICU) patients. Persisting thrombocytopenia in critically ill patients is associated with, but not causative of, increased mortality. Identificat...

BACKGROUND AND OBJECTIVES Apheresis platelet concentrates sometimes contain persistent aggregates (PA). Because apheresis involves extracorporeal circulation, we hypothesized that interactions between GPIbα and von Willebrand factor (VWF) underlie their origin. MATERIALS AND METHODS Platelets in donations with PA were compared to aggregate-free (AF) controls. Flow cytometry was used to determ...