Search results for "platelets"

Association between physical fitness and mean platelet volume in professional soccer players.

2014

Advanced Platelet-Rich Fibrin: A New Concept for Cell-Based Tissue Engineering by Means of Inflammatory Cells

2014

Choukroun's platelet-rich fibrin (PRF) is obtained from blood without adding anticoagulants. In this study, protocols for standard platelet-rich fibrin (S-PRF) (2700 rpm, 12 minutes) and advanced platelet-rich fibrin (A-PRF) (1500 rpm, 14 minutes) were compared to establish by histological cell detection and histomorphometrical measurement of cell distribution the effects of the centrifugal force (speed and time) on the distribution of cells relevant for wound healing and tissue regeneration. Immunohistochemistry for monocytes, T and B -lymphocytes, neutrophilic granulocytes, CD34-positive stem cells, and platelets was performed on clots produced from four different human donors. Platelets …

Cytosolic Ca2+Content and Membrane Fluidity of Platelets and Polymorphonuclear Leucocytes in Diabetes Mellitus

1995

Considering the role played by platelets and leucocytes in diabetic disease and keeping in mind the strong correlation between functional and metabolic aspects that characterizes this clinical condition, we evaluated, in two groups of diabetics, respectively the platelet and polymorphonuclear (PMN) cytosolic Ca2+ content (employing the fluorescent probe Fura 2-AM) and membrane fluidity (using the fluorescent probe TMA-DPH and considering the fluorescence polarization degree, inversely related to the membrane fluidity). From the obtained results, it is evident that the platelet cytosolic Ca2+ content does not distinguish normals from diabetics of type 1 and 2; the platelet membrane fluidity …

Effects of cigarette smoking or ingestion of nicotine on platelet 5-hydroxytryptamine (5-HT) levels in smokers and non-smokers.

1992

Platelets of healthy smokers and non-smokers were prepared and their content of 5-hydroxytryptamine was determined by HPLC with electrochemical detection. Platelet 5-HT levels in smokers (728 +/- 156 pmol per 10(8) platelets, mean +/- SEM, n = 9) were significantly higher than those in non-smokers (353 +/- 156 pmol per 10(8) platelets, n = 11). Smoking of a single cigarette caused a transient increase in platelet 5-HT levels by about 350% in non-smokers, but had no additional effect in smokers. Similarly, chewing of nicotine gum (4-8 mg nicotine) resulted in a transient increase in platelet 5-HT by about 100% in non-smokers, but not in smokers. In conclusion, smoking of cigarettes can cause…

Hematologic effects of recombinant human granulocyte colony-stimulating factor in patients with malignancy.

1989

Abstract The effect of recombinant human granulocyte colony-stimulating factor (G-CSF) on hematologic parameters was evaluated in a phase I clinical study in 18 patients with advanced malignancy. G-CSF was administered once daily as a 30-minute infusion for 14 days; three patients each were treated at increasing dose levels of 1, 3, 10, 30, and 60 micrograms kg-1 day-1. A transient decrease in neutrophil and monocyte counts was observed immediately after the G-CSF infusion, followed by a dose-dependent increase of up to 15-fold. G-CSF-induced neutrophils exhibited an increased O2- radical production, and serum levels of enzymes related to granulocyte turnover, including lysozyme and elastas…

Relapse Rate in Survivors of Acute Autoimmune Thrombotic Thrombocytopenic Purpura Treated with or without Rituximab.

2018

Background Autoimmune thrombotic thrombocytopenic purpura (iTTP) is caused by autoantibody-mediated severe a disintegrin and metalloprotease with thrombospondin type 1 repeats, member 13 (ADAMTS13) deficiency leading to micro-angiopathic haemolytic anaemia (MAHA) and thrombocytopenia with organ damage. Patients survive with plasma exchange (PEX), fresh frozen plasma replacement and corticosteroid treatment. Anti-CD20 monoclonal antibody rituximab is increasingly used in patients resistant to conventional PEX or relapsing after an acute bout. Objective This retrospective observational study focused on the relapse rate and possible influencing factors including treatment with rituximab first…

Predictive value of venous thromboembolism (VTE)-BLEED to predict major bleeding and other adverse events in a practice-based cohort of patients with…

2018

Summary Venous thromboembolism (VTE)‐BLEED, a decision tool for predicting major bleeding during chronic anticoagulation for VTE has not yet been validated in practice‐based conditions. We calculated the prognostic indices of VTE‐BLEED for major bleeding after day 30 and day 90, as well as for recurrent VTE and all‐cause mortality, in 4457 patients enrolled in the international, prospective XALIA study. The median at‐risk time was 190 days (interquartile range 106–360). The crude hazard ratio (HR) for major bleeding after day 30 was 2·6 [95% confidence interval (CI) 1·3–5·2] and the treatment‐adjusted HR was 2·3 (95% CI 1·1–4·5) for VTE‐BLEED high (versus low) risk patients: the correspondi…

Platelets, eicosanoids and aging.

1992

Prostacyclin receptor desensitization is a reversible phenomenon in human platelets.

1997

Background Long-term exposure of platelets to endogenous or exogenous prostacyclin or its analogues might result in desensitization of the platelet prostacyclin receptor in vitro and in vivo accompanied by a loss in receptor density on the platelet surface and a reduced sensitivity toward the inhibitory effects of prostacyclins. However, the reversibility of this process in platelets has not yet been investigated. Methods and Results Human platelets desensitized by the chemically stable prostacyclin analogue iloprost showed a significant reduction in [ 3 H]-iloprost binding sites that was reversed by saponin permeabilization. This indicates functionally active internalized prostacyclin rec…

Effects of pathogen reduction systems on platelet microRNAs, mRNAs, activation, and function

2014

Pathogen reduction (PR) systems for platelets, based on chemically induced cross-linking and inactivation of nucleic acids, potentially prevent transfusion transmission of infectious agents, but can increase clinically significant bleeding in some clinical studies. Here, we documented the effects of PR systems on microRNA and mRNA levels of platelets stored in the blood bank, and assessed their impact on platelet activation and function. Unlike platelets subjected to gamma irradiation or stored in additive solution, platelets treated with Intercept (amotosalen + ultraviolet-A [UVA] light) exhibited significantly reduced levels of 6 of the 11 microRNAs, and 2 of the 3 anti-apoptotic mRNAs (B…