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Introduction Platelet function testing with flow cytometry has additional value to existing platelet function testing for diagnosing bleeding disorders, monitoring anti-platelet therapy, transfusion medicine and prediction of thrombosis. The major challenge is to use this technique as a diagnostic test. The aim of this study is to standardize preparation, optimization and validation of the test kit and to determine reference values in a population of 129 healthy individuals. Methods Platelet function tests with 3 agonists and antibodies against P-selectin, activated alpha IIb beta 3 and glycoprotein Ib (GPIb), were prepared and stored at -20 degrees C until used. Diluted whole blood was added and platelet activation was quantified by the density of activation markers, using flow cytometry. Anti-mouse Ig. particles were included to validate stability of the test and to standardize results. Reference intervals were determined. Results Blood stored at room temperature (RT) for up to 4h after blood donation and preheated/tested at 37 degrees C resulted in stable results (%CV

Made available in DSpace on 2018-12-11T16:59:32Z (GMT). No. of bitstreams: 0 Previous issue date: 2016-01-01 Aims We determined whether decreased reactive oxygen species (ROS) production in the aorta of pregnant spontaneously hypertensive rats (SHR) resulted in increased nitric oxide (NO) bioavailability and hyporeactivity to phenylephrine (PE). Main methods Systemic and aortic oxidative stress were measured in pregnant and non-pregnant Wistar rats and SHR. Furthermore, the hypotensive effects of apocynin (30 mg/kg) and Tempol (30 mg/kg) were analyzed. Intact aortic rings of pregnant and non-pregnant rats were stimulated with PE in the absence of or after incubation (30 min) with apocynin (100 μmol/L). The effect of apocynin on the concentrations of NO and ROS were measured in aortic endothelial cells (AEC) using DAF-2DA (10 mmol/L) and DHE (2.5 mmol/L), respectively. Western blotting was performed to analyze eNOS, NOX1, NOX2, NOX4 and SOD expression. ROS production was analyzed by the lucigenin chemiluminescence method. Key findings Aortic oxidative stress and ROS concentration in AEC were reduced in pregnant Wistar rats and SHR, when compared to non-pregnant rats. ROS production and NOX1, NOX2 and NOX4 expression in the aortas were decreased in pregnant SHR, but not in pregnant Wistar rats. Increased eNOS expression in aortas and NO concentration in AEC were observed in pregnant Wistar rats and SHR. Apocynin reduced PE-induced vasoconstriction in the aortas of non-pregnant Wistar rats and SHR, and pregnant Wistar rats, but not in the aortas of pregnant SHR. Significance Taken together, these results suggest that ROS production was decreased in the aortas of pregnant SHR and could contribute to higher NO bioavailability and hyporeactivity to PE in the aortas of pregnant SHR. Programa de Pos-Graduacao Multicentrico em Ciencias Fisiologicas SBFis Department of Basic Sciences School of Dentistry of Araçatuba UNESP - Univ Estadual Paulista School of Pharmacy of Araçatuba UNIP - Univ Paulista Department of Psychiatry Nursing and Human Sciences College of Nursing of Ribeirão Preto USP - University of São Paulo Department of Basic Sciences School of Dentistry of Araçatuba UNESP - Univ Estadual Paulista

Background Hemorrhagic shock is associated with changes in vascular responsiveness that may lead to organ dysfunction and, ultimately, multiple organ dysfunction syndrome. Volatile anesthetics interfere with vasoresponsiveness, which may contribute to organ hypoperfusion. In this study, the authors examined the influence of adjunct nitrous oxide on the vascular responsiveness after short-term hemorrhagic shock under isoflurane anesthesia. Methods Spontaneously breathing mice (n = 31, 27.6 +/- 0.31 g) were anesthetized with isoflurane (1.4%) or with isoflurane (1.4%) and adjunct nitrous oxide (66%). Both groups were divided into Sham, Shock, and Resuscitated groups. Vascular reactivity to phenylephrine and acetylcholine and expression of cyclooxygenases were studied in the aorta. Results In the isoflurane-anesthetized groups, the contractile response to phenylephrine was increased in the Shock as compared with the Sham and Resuscitated groups (Emax = 3.2 +/- 0.4, 1.2 +/- 0.4, and 2.5 +/- 0.5 mN, respectively). Adjunct nitrous oxide increased phenylephrine contraction to a similar level in all three groups. In the Sham isoflurane group, acetylcholine caused a biphasic response: An initial relaxation followed by a contractile response sensitive to cyclooxygenases inhibition by indomethacine. The contractile response was abrogated in the isoflurane-anesthetized groups that underwent shock. In all groups, adjunct nitrous oxide preserved the contractile phase. Shock induced a down-regulation of cyclooxygenases-1, which was normalized by adjunct nitrous oxide. Conclusion Adjunct nitrous oxide attenuates shock-induced changes in vascular reactivity and cyclooxygenases expression of mice under isoflurane anesthesia. This implies that vascular reactive properties during anesthesia in hemorrhagic shock conditions may be influenced by the choice of anesthetics.