Search results for "erythrocytes"
showing 10 items of 218 documents
Determination of acetylcholine, nitrostigmine and acetylcholinesterase activity in four patients with severe nitrostigmine (E 605 forte) intoxication.
1974
Concentrations of acetylcholine and nitrostigmine as well as acetylcholinesterase activity were determined in 4 patients with severe nitrostigmine intoxication. In the acute phase of the intoxication, acetylcholine levels up to 36 and 55 ng/ml were found in blood plasma and cerebrospinal fluid, respectively. At the same time no activity of acetylcholinesterase in plasma and erythrocytes was detected. Acetylcholinesterase activity gradually recovered at the end of the second week. In the first 3 days after the ingestion plasma nitrostigmine concentrations ranged from 409 to 86 ng/ml. At the end of the third week nitrostigmine was still found in a concentration of about 1 ng/ml plasma. Redist…
External and internal exposure of wine growers spraying methyl parathion.
2005
Organophosphates, used in agriculture, are readily absorbed through the skin. We investigated the relationship between dermal and inhalative methyl parathion exposure and the plasma levels. Twenty-three healthy wine growers sprayed the insecticide for 50 min. Fluorescent brilliant sulfoflavin was added to the spraying fluids and filter papers were fixed on the subjects. The filter papers were used to evaluate the amount of brilliant sulfoflavine on the unprotected skin fluorometrically. Inhalative exposure was measured with personal air sampler. Plasma concentrations of methyl parathion and its metabolite methyl paraoxon were determined with gas chromatography. Cholinesterase activity in se…
Oxidant and antioxidant status in mothers and their newborns according to birthweight
2008
The aim of this study is to determine the oxidant and antioxidant status in Algerian mothers and their newborns according to birth weight.Subjects for the study were consecutively recruited from Tlemcen hospital. 139 pregnant women and their newborns were included. The plasma total antioxidant activity (ORAC), vitamins A, C, E, hydroperoxides, carbonyl proteins, and erythrocyte antioxidant enzyme activities (catalase, glutathione peroxidase, glutathione reductase and superoxide dismutase) were measured on mothers and their newborns. Lipid and lipoprotein parameters were also determined. The results were assessed in accordance with small for gestational age (SGA), appropriate (AGA) and large…
Oral supplements of vitamin E improve measures of oxidative stress in plasma and reduce oxidative damage to LDL and erythrocytes in β-thalassemia int…
2001
Fifteen beta-thalassemia intermedia patients, not requiring chronic transfusional therapy, were monitored in order to check their antioxidant status, and the lipid oxidation products in plasma, LDL, and erythrocytes before and during a 9-month oral treatment with 600 mg/day vitamin E. The low level of vitamin E, and high level of malondialdehyde in plasma clearly tended to normalize after three months (P < .001), and were quite similar to control after six months. The abnormally low level of vitamin E in LDL and the four times higher than control basal level of conjugated dienes (LDL-CD), were not modified after three months of treatment. Significant changes of LDL-VE (P < .05) and of the b…
Studies on erythrocyte acetylcholinesterase in essential hypertension.
1982
There is accumulating evidence that acetylcholinesterase (AChE might be involved in the transport of sodium across biological membranes. Consequently, because in primary hypertension abnormalities in the transport of sodium by red blood cells have been documented. AChE activities were measured in hemoglobin-free red-blood-cell membranes of patients with essential hypertension. In the absence of any effectors, the Michaelis constant of AChE for acetylcholine (Km) was 1.57 . 10(-5) mol/l, both in normotensives and in hypertensives. Sodium inhibited AChE at low substrate concentrations, whereas the enzyme was activated by sodium at moderate and high substrate levels. With increasing sodium, th…
Effect of exercise training on in vitro LDL oxidation and free radical-induced hemolysis: the HERITAGE Family Study.
2006
Oxidant stress and overproduction of reactive oxygen species (ROS) contribute to the development of cardiovascular disease. Oxidative modifications of low-density lipoproteins (LDL) are thought to play an early and critical role in atherogenesis. LDL oxidation can be reproduced in vitro, but results usually show a large interindividual variation not entirely explained by the environment. Free radical-induced hemolysis is also proposed to reveal the overall antioxidant capacity. The roles of genetic factors and exercise on the variability of both measures were investigated. The study was conducted in 146 healthy individuals from 28 families participating in a 20-week exercise-training progra…
Lipid peroxidation and antioxidant enzyme activities in patients with type 1 diabetes mellitus
1999
To evaluate oxidative stress in type I diabetes mellitus, two antioxidant enzymes in erythrocytes, copper-zinc superoxide dismutase (SOD EC 1.15.1.1.) and seleno-dependent glutathione peroxidase (GSH-Px; EC 1.11.19), and two indexes of peroxidation in plasma, thiobarbituric acid reactive substances (TBARS) and organic hydroperoxides (OHP), were measured in 118 patients with insulin-dependent diabetes mellitus (IDDM), classified in accordance with the presence or absence of vascular complications and the degree of metabolic control established by the HbA1c level. Ninety healthy subjects made up the control group. According to our results, plasmatic TBARS and OHP concentrations are significan…
Effects of Glutathione on Red Blood Cell Intracellular Magnesium
1999
Abstract —Recent evidence suggests that the endogenous antioxidant glutathione may play a protective role in cardiovascular disease. To directly investigate the role of glutathione in the regulation of glucose metabolism in hypertension, we studied the acute effects of in vivo infusions of this antioxidant (alone or in combination with insulin) on whole body glucose disposal (WBGD) using euglycemic glucose clamp and the effects on total red blood cell intracellular magnesium (RBC-Mg) in hypertensive (n=20) and normotensive (n=30) subjects. The relationships among WBGD, circulating reduced/oxidized glutathione (GSH/GSSG) levels, and RBC-Mg in both groups were evaluated. The in vitro effects…
Magnesium Responsiveness to Insulin and Insulin-Like Growth Factor I in Erythrocytes from Normotensive and Hypertensive Subjects
1998
Depletion of intracellular free magnesium (Mg(i)) is a characteristic feature of insulin resistance in essential hypertension, but it is not clear to what extent low Mg(i) levels contribute to insulin resistance, result from it, or both. As insulin-like growth factor I (IGF-I) may improve insulin resistance, we investigated whether this peptide could similarly improve Mg(i) responsiveness to insulin in hypertension, and whether this effect was related to any direct IGF-I effect on Mg(i). 31P-Nuclear magnetic resonance spectroscopy was used to measure Mg(i) in erythrocytes from 13 fasting normotensive and 10 essential hypertensive subjects before and 30, 60, and 120 min after incubation with…
Insulin-like growth factor 1 and sodium-lithium countertransport in essential hypertension and in hypertensive left ventricular hypertrophy
1993
The aim of this work was to study the insulin-like growth factor 1 (IGF1), a substance able to promote cell proliferation in vascular smooth muscle, in patients with mild-to-moderate hypertension and to analyse its relationship to sodium-lithium countertransport, a genetic marker of hypertension that is related to cardiovascular complications.We studied 32 hypertensive subjects, some with left ventricular hypertrophy, and 14 healthy subjects. Fasting plasma IGF1 was measured by means of a radioimmunoassay after octadecylsilica chromatography and Na(+)-Li+ countertransport was determined by the method of Canessa.Hypertensive patients had higher values of both IGF1 and Na(+)-Li+ countertransp…