Search results for "Oxide"
showing 10 items of 6424 documents
Erythrocyte deformability and nitric oxide metabolites in athletes before and after a cardiopulmonary test.
2009
OBJECTIVE: To evaluate erythrocyte deformability, nitric oxide metabolites, and their modifications induced by exercise in athletes who practised different sports. DESIGN: This evaluation was effected before and after cardiopulmonary test, using a cycloergometer. SETTING: The study was performed in the Department of Internal Medicine, Cardiovascular and Renal Diseases of the University of Palermo. PARTICIPANTS: We enrolled 62 male athletes who practised endurance (n = 23), mixed (n = 20), and power (n = 19) sports and 20 sedentary male subjects as controls. ASSESSMENT OF RISK FACTORS: No subject had diabetes or hypertension or dyslipidemia. Five control subjects and 14 athletes were smokers…
Influence of risk factors on nitric oxide metabolites at the initial stage of juvenile acute myocardial infarction.
2009
Few data are accessible about the nitric oxide (NO) stable end-products (nitrite/NO2 − and nitrate/NO3 − :N O x) in acute coronary syndromes. An increase in inducible NO synthase (iNOS) was found during experimental myocardial infarction [13] and this increase persisted for 2 weeks. In experimental models of acute myocardial infarction (AMI) other authors [2] observed a NOx increase, a correlation between NOx level and iNOS activity and an inhibitory action carried out by S-methylisothiourea, that is an iNOS inhibitor [5]. The NOx level was also measured in a small group of patients with myocardial infarction in whom the peak of NOx elevation occurred 2 and 3 days after the onset of symptom…
Oxidative stress and maternal obesity: Feto-placental unit interaction
2013
Abstract Objective To determine oxidative stress markers in maternal obesity during pregnancy and to evaluate feto-placental unit interaction, especially predictors of fetal metabolic alterations. Patients and methods 40 obese pregnant women (prepregnancy BMI > 30 kg/m²) were compared to 50 control pregnant women. Maternal, cord blood and placenta samples were collected at delivery. Biochemical parameters (total cholesterol and triglycerides) and oxidative stress markers (malondialdehyde, carbonyl proteins, superoxide anion expressed as reduced Nitroblue Tetrazolium, nitric oxide expressed as nitrite, reduced glutathione, catalase, superoxide dismutase) were assayed by biochemical methods. …
Nitric oxide mediates abnormal responsiveness of thyroid arteries in methimazole-treated patients.
2005
Objective: We studied the intervention of nitric oxide (NO), prostacyclin and endothelium-derived hyperpolarizing factor (EDHF) in mediating responses to acetylcholine in thyroid arteries from euthyroid and methimazole-treated (MT) patients. Design and methods: Branches of the superior thyroid artery were obtained from 19 euthyroid patients and 17 MT patients (euthyroid at the time of surgery) undergoing total thyroidectomy or hemithyroidectomy. Artery rings were suspended in organ baths for isometric recording of tension. Results and conclusions: Acetylcholine caused endothelium-dependent relaxation of greater magnitude in arteries from MT patients (pD2 (−log EC50) values were 7.68±0.19 in…
Human corticotropin-releasing factor (hCRF) is a potent respiratory analeptic. Physiological and clinical aspects.
1986
During intravenous corticotropin-releasing factor stimulation tests we observed a deepening of the tidal volume in 35 patients. To investigate this presumed respiratory stimulation we measured respiratory parameters in 12 healthy male volunteers in a single-blind placebo-controlled trial. The intravenous 60-s infusion of 100 micrograms of human corticotropin-releasing factor induced a very potent respiratory stimulation in every subject: respiratory minute volume (mean +/- S.D.) increased by 81% from 6.319 +/- 0.577 to 11.464 +/- 1.264 liters per min (P less than 0.001), whereas there was only a slight rise in the mean respiratory rate from 12.4 +/- 3.0 to 14.7 +/- 2.7 breaths per min (P le…
Human Corticotropin-Releasing Hormone in Man: Dose-Response of Minute Ventilation and End-Tidal Partial Pressures of Carbon Dioxide and Oxygen*
1987
The respiratory stimulant properties of iv injections of 33, 67, and 100 micrograms synthetic human corticotropin-releasing hormone (hCRH) were studied in 12 normal men in a single blind, placebo-controlled trial. All doses of hCRH induced a respiratory stimulation in every subject, and the stimulation was dose dependent. The onset of respiratory stimulation occurred within 15-30 sec after hCRH infusion was started. Initially, there was an increase in tidal volume (VT), followed by an increase in respiratory rate. The maximum minute ventilation (VE) occurred 60-120 sec after starting the injection. The 33-micrograms hCRH dose induced a 35% increase in VE from 6.3 +/- 0.6 (+/- SD) to 9.7 +/-…
Assessment of salivary and serum antioxidant status in patients with recurrent aphthous stomatitis
2009
Objective: The aim of this study was to determine the possible association of oxidant/antioxidant status and recurrent aphthous stomatitis (RAS). Study design: The study consis ted of thirty-one patients with RAS and thirty-two healthy controls from whom saliva and blood samples were collected. Superoxide dismutase (SOD), glutathione peroxidase (GSHPx) and catalase (CAT) were measured in erythrocytes and total antioxidant status (TAS) was measured in plasma and saliva. Results: Erythrocyte SOD activity was significantly lower in RAS patients in comparison to healthy controls (P=0.012). No significant differences were found in erythrocyte GSHPx, CAT activities, and salivary and plasma TAS be…
A breathing-retraining procedure in treatment of sleep-onset insomnia: theoretical basis and experimental findings.
1995
Increase in CO2 has a sedative effect upon the central nervous system, and the beginning of sleep coincides with modifications in breathing, decrease in ventilation, and in pCO2 increase. In this paper is described a technique of breathing that is useful in producing drowsiness in a very short time. 46 insomniacs were randomly allocated to either a treatment or control condition. In the former, patients were trained in the breathing process. The control group was taught no breathing process. Latencies to sleep for the insomniacs confirmed that the breathing process was useful in producing drowsiness. Theoretical bases are discussed.
Influence of Endothelial Nitric Oxide on Adrenergic Contractile Responses of Human Cerebral Arteries
1996
The present study was designed to investigate the influence of the endothelium and that of the L-arginine pathway on the contractile responses of isolated human cerebral arteries to electrical field stimulation (EFS) and norepinephrine. Rings of human middle cerebral artery were obtained during autopsy of 19 patients who had died 3–8 h before. EFS (1–8 Hz) induced frequency-dependent contractions that were abolished by tetrodotoxin, prazosin, and guanethidine (all at 10-6 M). The increases in tension were of greater magnitude in arteries denuded of endothelium. NG-monomethyl L-arginine (L-NMMA 10-4 M) potentiated the contractile response to EFS in artery rings with endothelium but did not …
Clonidine induces nitric oxide- and prostaglandin-mediated vasodilation in healthy human skin
2005
Sustained sympathetic activation not only leads to vasoconstriction but also might induce paradox vasodilation. This study was performed to explore whether and how alpha(2)-receptor stimulation mediates this vasodilation. We investigated 11 healthy subjects in 33 dermal microdialysis (MD) sessions. After nerve trunk blockade, MD fibers were inserted and perfused with physiological saline until skin trauma-related vasodilation subsided. Thereafter, fibers were perfused with either clonidine solutions (10(-3), 5 x 10(-4), 10(-4) mol/l), N(G)-monomethyl-l-arginine (L-NMMA; nitric oxide synthase blocker), acetylsalicylic acid (ASA; cyclooxygenase blocker), or combinations of these. Laser-Dopple…