Search results for "Platelet"
showing 10 items of 786 documents
Differences in platelet growth factor release and leucocyte kinetics during autologous platelet gel formation.
2006
Three commercial systems for whole blood separation were compared to obtain the buffy coat composed of platelet-rich plasma (BC-PRP) and leucocytes . These samples of the buffy coat were used to make a platelet gel (PG), which was used to measure platelet growth factor (PGF) release, to perform a white blood cell (WBC) count and to measure myeloperoxidase (MPO) release from WBCs. Aliquots of whole blood obtained from ten volunteers were distributed either to a blood cell separator (The Electa Cell-Separator (TM), E-CS) or to a tabletop centrifuge (Gravitational Platelet Sequestration System (TM), GPS) to prepare the BC-PRP. The third system combines the BC-PRP production by E-CS with a micr…
Glycated albumin with loss of fatty acid binding capacity contributes to enhanced arachidonate oxygenation and platelet hyperactivity: relevance in p…
2014
High plasma concentrations of nonesterified fatty acids (NEFAs), transported bound to serum albumin, are associated with type 2 diabetes (T2D). The effects of albumin on platelet function were investigated in vitro. Modifications of albumin, such as those due to glycoxidation, were found in patients with T2D, and the consequences of these modifications on biological mechanisms related to NEFA handling were investigated. Mass spectrometry profiles of albumin from patients with T2D differed from those from healthy control subjects. Diabetic albumin showed impaired NEFA binding capacity, and both structural and functional alterations could be reproduced in vitro by incubating native albumin wi…
Involvement of hydrogen and lipid peroxides in acute tobacco smoking-induced platelet hyperactivity
1995
Previous studies have established that cigarette smoking results in acute platelet hyperaggregability. We investigated whether changes in plasma oxidative properties could occur after smoking and whether such changes could be responsible for this enhanced platelet activity. In the present work, we report that platelets from nonsmokers become hyperactive after incubation with plasma prepared from blood of smokers obtained 10 min after smoking. This effect was not observed with presmoking plasma and could be inhibited in vitro by adding either catalase or reduced glutathione plus peroxidase to plasma or 2,6-di-tert-butyl-p-cresol (BHT) to platelets before incubation. Comparison of pre- and p…
Curasan PRP kit vs. PCCS PRP system
2002
An important reason to improve methods of isolating platelet-rich plasma (PRP) is the potential use of autologous thrombocyte growth factors. In addition to discontinuous cell separation, two methods for extracting PRP that can be performed directly by the surgeon are now available. This study compared the suitability of these two methods for the preparation of PRP. Whole blood was drawn from 47 healthy donors (18 men, 29 women) aged 20-59 years (mean 29.9, SD 7.7). For each donor, PRP was separated by the PCCS method (PCCS Kit, 3i Implant Innovations, Palm Beach Gardens, FL, USA) and by the Curasan method (analogous to the PRP kit, Curasan, Kleinostheim, Germany). Thrombocyte counts differ…
Evaluation of osteoblastic activity in extraction sockets treated with platelet-rich fibrin
2014
Objective: The aim of this study was to determine whether the use of platelet rich fibrin (PRF) improved the healing of extraction sockets. Study Design: A total of 20 patients with bilateral soft tissue impacted mandibular third molars were included in this study. The left and right third molars were extracted during the same session. Subsequently, the PRF membrane was randomly administered to one of the extraction sockets, whereas the contra lateral sockets were left without treatment. On postoperative 30. and 90. days, panoramic images and bone scintigrams were taken to evaluate the bone healing between PRF-treated and non-PRF-treated sockets. Also, periodontal evaluation was performed i…
Results of an Open Clinical Trial of Brofaromine (CGP 11 305 A), a Competitive, Selective, and Short-Acting Inhibitor of MAO-A in Major Endogenous De…
1987
In an open clinical trial the authors treated 18 hospitalized patients suffering from endogenous depression with brofaromine (CGP 11305A), a competitive, selective, and short-acting inhibitor of type A monoamine oxidase (MAO). Four patients were defined as good responders, as they had a final HAMD score of between 0 and 7 points. Four patients were judged as improved, with final HAMD scores of between 8 and 15 points, while the remaining eight patients failed to respond (final HAMD score greater than or equal to 16 points). The major observations were a beneficial influence on drive in most patients, while paranoid symptoms worsened markedly, rendering the substance contraindicated in psych…
PLA1/A2 polymorphism of the platelet glycoprotein receptors IIIA in Behçet's disease
2010
OBJECTIVES: To investigate potential associations between the PlA1/A2 polymorphism of the platelet glycoprotein receptor IIIA (GpIIIa) gene and venous thrombosis and other clinical manifestations in Italian patients with Behçet's disease (BD). METHODS: Two hundred consecutive Italian patients satisfying the International Study Group criteria for BD who were followed up for seven years and 241 healthy Italian age- and gender-matched blood donors were molecularly genotyped for the PlA1/A2 polymorphism of the platelet GpIIIa gene; 118 and 117 of the 200 BD patients were also respectively genotyped for factor V Leiden and prothrombin gene G20210A polymorphisms. A standard microlymphocytotoxicit…
The Use of Frozen-Thawed Platelet-Derived Phospholipids as a Confirmatory Test for the Diagnosis of Lupus Anticoagulants. Comparison with Two Commerc…
1999
Lupus anticoagulants (LAs) belong to acquired circulating anticoagulants interfering with phospholipid-dependent coagulation tests. Owing to the remarkable variability among patients, SSC guidelines recommend more than one test to detect and confirm the presence of LAs. However, this is an expensive procedure and greatly raises the work load of the laboratory. A standardised platelet-derived phospholipid preparation was obtained and platelet neutralisation (PNP) procedures with APTT and DRVVT reagents were performed on plasmas from 16 patients with LAs and from 41 control subjects. In comparisons, STAclot-PNP and DVVconfirm clotting assays were conducted. PNP by using APTT or DRVVT reagents…
Clinical Features And Course Of Refractory Anemia With Ring Sideroblasts Associated With Marked Thrombocytosis
2012
Background Refractory anemia with ring sideroblasts associated with marked thrombocytosis was proposed as a provisional entity in the 2001 World Health Organization classification of myeloid neoplasms and also in the 2008 version, but its existence as a single entity is contested. We wish to define the clinical features of this rare myelodysplastic/myeloproliferative neoplasm and to compare its clinical outcome with that of refractory anemia with ring sideroblasts and essential thrombocythemia. Design and Methods We conducted a collaborative retrospective study across Europe. Our database included 200 patients diagnosed with refractory anemia with ring sideroblasts and marked thrombocytosis…
ABNORMALLY HIGH THROMBOXANE BIOSYNTHESIS IN HOMOZYGOUS HOMOCYSTINURIA. EVIDENCE FOR PLATELET INVOLVEMENT AND PROBUCOL-SENSITIVE MECHANISM.
1993
Homocystinuria due to homozygous cystathionine beta-synthase deficiency is an inborn error of metabolism characterized by a high incidence of thrombosis and premature atherosclerosis. We evaluated TXA2 biosynthesis in vivo and several in vitro tests of platelet function in 11 homocystinuric patients and 12 healthy controls. In vitro, patients' platelet aggregation was within control values as were TXB2 formation, fibrinogen binding, and ATP secretion in response to thrombin. In contrast, the urinary excretion of 11-dehydro-TXB2, a major enzymatic derivative of TXA2, was > 2 SD of controls in all patients (1,724 +/- 828 pg/mg creatinine, mean +/- SD, in patients vs. 345 +/- 136 in controls, …