Search results for "Nitrites"
showing 10 items of 75 documents
Cognitive impairment is related to oxidative stress and chemokine levels in first psychotic episodes.
2011
Abstract Introduction This study measures the levels of various markers of oxidative stress and inflammation in blood samples from first-episode psychosis (FEP) patients, and examines the association between these peripheral biomarkers and cognitive performance at 6 months after treatment. Methods Twenty-eight FEP patients and 28 healthy controls (matched by age, sex and educational level) had blood samples taken at admission for assessment of total antioxidant status, superoxide dismutase (SOD), total glutathione (GSH), catalase (CAT), glutathione peroxidase, lipid peroxidation, nitrites and the chemokine monocyte chemoattractant protein-1 (MCP-1). A battery of cognitive tests was also app…
Nitric oxide metabolites (nitrite and nitrate) in young patients with recent acute myocardial infarction
2008
Nitric oxide (NO) has a role in the pathophysiology of acute and chronic cardiovascular events. We studied the plasma concentration of NO stable end products (nitrite and nitrate - NO x ) in 43 patients aged <46 years, with recent acute myocardial infarction (AMI). The evaluation was effected at the initial stage, after 3 and 12 months. We subdivided the patients into subgroups according to the number of the main cardiovascular risk factors and to the extent of coronary disease. In the whole group the NO x concentration was initially increased and progressively decreased after 3 and 12 months, remaining at both times significantly higher than in control subjects. The patients with more risk…
Nitric oxide metabolites and erythrocyte deformability in a group of subjects with obstructive sleep apnea syndrome
2014
Our aim was to evaluate nitric oxide metabolites (nitrite and nitrate), expressed as NOx, and erythrocyte deformability, expressed as elongation index, in a group of subjects with obstructive sleep apnea syndrome (OSAS). We enrolled 48 subjects (36 men and 12 women; mean age 50.3 ± 14.68 yrs) with OSAS diagnosed after a 1-night cardiorespiratory sleep study. OSAS severity was assessed evaluating the apnea/hypopnea index (AHI) and subjects were subdivided in two subgroups: Low (L = AHI 30). NOx was examined converting nitrate into nitrite with a nitrate reductase and then assessing nitrite with spectrophotometry after the addition of Griess reagent. The elongation index was obtained using th…
DNA damage in leukocytes and serum nitrite concentration are negatively associated in type 1 diabetes.
2020
Abstract Chronic hyperglycaemia leads to DNA damage in diabetes and might be associated with nitrosative stress. In this study, we aimed at assessing the level of DNA strand breaks in leukocytes, serum nitrite and nitrate in patients with type 1 diabetes and healthy controls and associations of these parameters with diabetes-related outcomes in a prospective study. The level of DNA damage was determined in 71 patients with type 1 diabetes and 57 healthy controls by comet assay and scored with arbitrary units (AU). The chemiluminescence method was used to measure nitrite and nitrate. Clinical information and data on consumption of alcohol, physical activity and smoking were collected. Progre…
Behaviour of nitric oxide metabolites in unprofessional athletes before and after a cardiopulmonary test.
2010
Physical training causes an increase in nitric oxide (NO) production [2, 3, 8, 9] and this datum explains the link between exercise and endothelium and seems to demonstrate how regular training upregulates eNOS expression, although it is not sure if this upregulation is due to shear stress or metabolic factors [3]. However, it must be underlined that besides to be directly influenced by exogenous NO, erythrocytes express a functional NOS [5, 6, 11, 13] that raises the circulation NO pool. The literature data describe that an 8-week exercise training induced an increase in plasma levels of NO metabolites (NOx), that persisted four weeks after interruption of training [8]. A similar trend was…
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…
Limb Ischemic Conditioning Induces Oxidative Stress Followed by a Correlated Increase of HIF-1α in Healthy Volunteers.
2019
Background Local and remote ischemic preconditioning has been used as a protective intervention against ischemia/reperfusion (I/R) damage in several preclinical and clinical studies. However, its physiological mechanisms are not completely known. I/R increases the production of reactive oxygen species, which also serve as messengers for a variety of functions. Hypoxia-inducible factor 1 alpha (HIF-1α) is probably the most important transcription factor mediator of hypoxic signaling. Objective We hypothesized that limb ischemic conditioning (LIC) induces a local oxidative/nitrosative stress and a correlated increase of HIF-1α plasma levels. Methods An observational, prospective, and single-c…
Effect of fish oil on LDL oxidation and plasma homocysteine concentrations in health.
2003
Oxidation of low-density lipoprotein (LDL) and hyperhomocysteinemia are believed to play a role in therogenesis. Whether n-3 polyunsaturated fatty acids increase LDL susceptibility to oxidation or influence homocysteine (Hcy) metabolism has long been a subject of controversy. In this study, we evaluated the effect of 8 weeks of dietary supplementation with 6 g/day of fish oil (FO; 3 g of n-3 fatty acids) on plasma lipoproteins, in vitro LDL peroxidation, antioxidant status, and plasma Hcy concentrations in 16 normolipidemic subjects. FO rapidly and significantly (P < .01) decreased plasma total and very low density lipoprotein triglyceride concentrations and had no effect on LDL or high-den…
Plasma concentration of asymmetric dimethylarginine, an endogenous inhibitor of nitric oxide synthase, is elevated in hyperthyroid patients.
2002
Cardiovascular manifestations are frequent findings in patients with thyroid hormone disorders. Nitric oxide (NO) plays a key role in vascular, endothelial-mediated relaxation. NO is synthesized from L-arginine by NO synthase, an enzyme inhibited by endogenous compounds, mainly asymmetric dimethylarginine [asymmetric N(G),N(G)-dimethyl-L-arginine (ADMA)]. The aim of our work was to investigate whether plasma L-arginine and dimethylarginine concentrations and NO production are altered in hypo- and hyperthyroid patients, compared with control subjects. L-arginine, ADMA and symmetric dimethylarginine were analyzed by HPLC. NO was measured as plasma nitrite plus nitrate (NO(x)) concentration by…
Determination of nitrite by inhibition of the chemiluminescence of acriflavine in a flow-injection assembly
2001
The indirect determination of nitrite was performed with a flow-injection assembly on the basis of the inhibition of the analytical output obtained in a luminometer by oxidation of acriflavine. The acriflavine solution merged with the nitrite and the resulting mixture was injected into a pure water stream. This solution merged with the oxidant solution (potassium permanganate in sulfuric acid medium) and the resulting chemiluminiscence was affected (inhibited) by the presence of nitrite after reaction with the aminoacridine. The method was applicable over the range 10–800 μg l−1 of nitrite with a correlation coefficient of 0.9960. The relative standard deviation was 1.4% and the throughput …