Search results for "Platelet"

Quantification of thrombocyte growth factors in platelet concentrates produced by discontinuous cell separation.

2002

Platelet concentrates (PC) are increasingly used to increase bone regeneration in pre-prosthetic surgery. Although it is generally appreciated that certain growth factors (PDGF, TGF, EGF, and ECGF) are present in thrombocyte preparations, relatively little is known about these components in quantitative terms. The study reported here analysed the amounts of growth factors in PC produced under standard conditions from healthy volunteers. All the blood samples (237 in total) were analysed using Quantikine ELISA kits (R and D). The mean +/- SD platelet count in whole blood from these donors was 262,000+/-58,000/microl, while in PC produced by discontinuous cell separation it was 1.419,000+/-33…

Increased thromboxane biosynthesis in type IIa hypercholesterolemia.

1992

BACKGROUND Increased platelet thromboxane (TX)A2 production has been described in type IIa hypercholesterolemia. To verify the relevance of these capacity-related measurements to the actual rate of TXA2 biosynthesis in vivo, we studied the urinary excretion of its major enzymatic metabolites in 46 patients with type IIa hypercholesterolemia and 20 age-matched controls. METHODS AND RESULTS Urinary 11-dehydro-TXB2 and 2,3-dinor-TXB2 were measured by previously validated radioimmunoassays. The excretion rate of 11-dehydro-TXB2 was significantly (p less than 0.001) higher in patients (68.7 +/- 35.1 ng/hr, mean +/- SD) than in controls (22.4 +/- 9.4 ng/hr), with metabolite excretion greater tha…

Effect of training status on the changes in platelet parameters induced by short–duration exhaustive exercise

2015

It is now well known that hemostasis is directly involved in the benefits induced by physical activity. It has recently been shown that the baseline mean platelet volume (MPV) may be a predictor of endurance performance. We aimed to explore whether platelet parameters are associated with VO2max as well as running duration and speed in a short-duration exhaustive exercise test. Thirty healthy male subjects (10 sedentary and 20 trained) performed an incremental running test until exhaustion. MPV, platelet distribution width (PDW), platelet (Plt) count, and plateletcrit (Pct) were determined before exercise, immediately after exercise and after 30′ recovery. Training status did not produce any…

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…

Mobilization of peripheral blood progenitor cells with a combination of cyclophosphamide, r-metHuSCF and filgrastim in patients with breast cancer pr…

2002

The objective of our study was to determine the effect of adding r-metHuSCF to Filgrastim and cyclophosphamide for mobilization of peripheral blood progenitor cells (PBPC), on collection of CD34(+) cells and engraftment after autologous stem cell transplant. Twenty-three patients with previously treated stage II-IV breast cancer received cyclophosphamide (3 g/m(2)), Filgrastim 5 microg/kg daily and r-metHuSCF 20 microg/kg daily. Two PBPC collections were performed on consecutive days starting the day the WBC count was above 7.5 x 10(3)/microl. Collection was performed between days +9 and +12 and the median number of CD34(+) cells collected was 9.9 x 10(6)/kg (1.1-53.1) and 6.6 x 10(6)/kg (1…

Blood rheology during chemotherapy in patients with ovarian cancer.

1998

The use of platinum based chemotherapy in ovarian malignancy and other cancer types is known to be associated with deep vein thrombosis. In a prospective study of 47 patients with ovarian cancer of International Federation of Gynecology and Obstetrics stage Ib-IV, serial rheological parameters were determined (plasma viscosity, red blood cell aggregation under conditions of stasis and low shear) in addition to hemoglobin, hematocrit, leukocytes, platelets, and fibrinogen. At the same time the incidence of deep vein thrombosis was recorded before, during six cycles of first line cisplatinum/epirubicin/cyclophosphamide chemotherapy, and 2 months thereafter (two-months check-up). Only six pati…