Search results for "STRESS"
showing 10 items of 6278 documents
Erythrocyte deformability in macrocytosis determined by means of ektacytometry techniques
2010
There is little information regarding the behaviour of red blood cell deformability in macrocytosis. We have determined in 114 patients with macrocytosis (MCV > 97 fL) and in 115 age and sex-matched subjects with normocytosis (VCM < 97 fL) erythrocyte deformability by means of ektacytometric techniques (Rheodyn SSD) measuring the erythrocyte elongation index (EEI) at 12, 30 and 60 Pa. Patients with macrocytosis showed statistically higher EEI at all the shear stresses tested when compared with controls (p < 0.001). When patients with macrocytosis were classified according to their main diagnosis as hepatic or renal disease, HIV and miscellaneous, 66.7%, 41.7%, 36.7% and 33.3% of patients, r…
Cardiovascular and autonomic responses to physiological stressors before and after six hours of water immersion
2013
The physiological responses to water immersion (WI) are known; however, the responses to stress following WI are poorly characterized. Ten healthy men were exposed to three physiological stressors before and after a 6-h resting WI (32–33°C): 1) a 2-min cold pressor test, 2) a static handgrip test to fatigue at 40% of maximum strength followed by postexercise muscle ischemia in the exercising forearm, and 3) a 15-min 70° head-up-tilt (HUT) test. Heart rate (HR), systolic and diastolic blood pressure (SBP and DBP), cardiac output (Q̇), limb blood flow (BF), stroke volume (SV), systemic and calf or forearm vascular resistance (SVR and CVR or FVR), baroreflex sensitivity (BRS), and HR variabili…
Erythrocyte deformability evaluated by laser diffractometry in polycythemia vera.
2012
We evaluated the erythrocyte deformability in a group of subjects with polycythemia vera (PV) using a Rheodyn-SSD Laser Diffractometer, at the shear stresses of 6, 12, 30 and 60 Pa. Our data showed a significant decrease of red cell deformability, expressed as elongation index (EI), in PV subjects compared with normal controls. These results suggest that the hyperviscosity syndrome accompanying this myeloproliferative disease may be considered a mixed form, resulting from the association of a polycythemic condition with a sclerocythemic disorder.
Behaviour of protein carbonyl groups in juvenile myocardial infarction.
2012
Acute myocardial infarction (AMI) is accompanied by oxidative stress, and protein oxidation is among the con- sequences of oxidative stress. We examined the plasma concentration of protein carbonyl groups (PC), a marker of protein oxidation, in a group of young subjects with AMI (45 men and 5 women; mean age 40.4 ± 4.8 yrs). We found a significant increase of PC (p < 0.001) in comparison with normal controls. No difference was observed between patients with AMI char- acterized by elevated ST segment and those without elevation of ST segment. There was no correlation between the ejection fraction and PC in the whole group nor in the subgroups of STEMI and non-STEMI patients. Subdividing the …
Interrelationships between lipid peroxidation and total antioxidant status in sedentary controls and unprofessional athletes.
2010
We examined the thiobarbituric acid-reactive substances (TBARS) as an index of lipid peroxidation, and the total antioxidant status (TAS) in 81 unprofessional athletes subdivided into three subgroups. The first group included 28 subjects who practised endurance sports, the second included 30 subjects who practised mixed sports, the third included 23 subjects who practised power sports. We enrolled also a group of 61 sedentary controls (SC). TBARS were increased and TAS was decreased in the whole group of athletes in comparison with SC; an almost similar behaviour was present also subdividing athletes according to the practised sport. A significant negative correlation between these two para…
Skeletal muscle blood flow and flow heterogeneity during dynamic and isometric exercise in humans
2002
The effects of dynamic and intermittent isometric knee extension exercises on skeletal muscle blood flow and flow heterogeneity were studied in seven healthy endurance-trained men. Regional muscle blood flow was measured using positron emission tomography (PET) and an [15O]H2O tracer, and electromyographic (EMG) activity was recorded in the quadriceps femoris (QF) muscle during submaximal intermittent isometric and dynamic exercises. QF blood flow was 61% ( P = 0.002) higher during dynamic exercise. Interestingly, flow heterogeneity was 13% ( P = 0.024) lower during dynamic compared with intermittent isometric exercise. EMG activity was significantly higher ( P < 0.001) during dynamic e…
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. …
ADMA, subclinical changes and atrial fibrillation in the general population.
2015
Abstract Background Pathways of oxidative stress, nitric oxide bioavailability and l-arginine derivatives are hypothesized to be related to atrial fibrillation (AF). Circulating methylated l-arginine metabolites can be assessed in the general population and may show an association with AF. Methods We determined l-arginine and its metabolites asymmetric dimethylarginine (ADMA), l-N ω -monomethylarginine (NMMA) and symmetric dimethylarginine (SDMA) in the population-based Gutenberg Health Study (n=5000), mean age 55±11years, 51% men, in association with clinical variables of AF such as electrocardiographic and echocardiographic measures and manifest AF. Results Individuals with AF (N=161), 71…
Marriage Dissatisfaction and the Risk of Sudden Cardiac Death Among Men
2018
Conflicts in marriage have been associated with potential risk of cardiovascular disease; however, there is lack of prospective evidence on the association between marriage satisfaction and sudden cardiac death (SCD). We aimed to assess the association between perceived level of marriage satisfaction and risk of SCD. This study employed the Kuopio Ischemic Heart Disease study, an ongoing prospective population-based study in Finland. Perceived level of marriage satisfaction was assessed in 2,262 men using a well-structured self-administered questionnaire. Multivariable adjusted Cox regression models were used to estimate hazard ratios (95% confidence interval [CI]) for SCD. During a median …
Hyperuricemia in acute heart failure. More than a simple spectator?
2007
Hyperuricemia is a prevalent condition in chronic heart failure (CHF), describing increased oxidative stress and inflammation. Although there is evidence that serum uric acid (UA) predicts mortality in CHF, its role as a prognostic biomarker in acute heart failure (AHF) has not yet been well assessed. The aim of this study was to determine if UA levels predict all-cause mortality. Additionally, as a secondary endpoint we sought the clinical predictors of UA serum level in this population.We analyzed 560 consecutive patients with AHF admitted in a single university center. UA (mg/dl) was measured during early hospitalization. Patient survival status was followed up after discharge (median fo…