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Stress Parameters (stress + parameter)
Kinds of Stress Parameters Selected AbstractsTo investigate the effect of Citrullus colocynthis (Schrad) fruit on oxidative stress parameters in type 2 diabetic patientsFOCUS ON ALTERNATIVE AND COMPLEMENTARY THERAPIES AN EVIDENCE-BASED APPROACH, Issue 2006H Fallah Husein [source] Oxidative stress parameters after combined fluoxetine and acetylsalicylic acid therapy in depressive patientsHUMAN PSYCHOPHARMACOLOGY: CLINICAL AND EXPERIMENTAL, Issue 4 2009Piotr Ga, ecki Abstract Objective There are numerous reports indicating disturbed equilibrium between oxidative processes and antioxidative defense in patients with depression. Moreover, depressive patients are characterized by the presence of elements of an inflammatory process, which is one of the sources of reactive oxygen species (ROS). In view of the above, it was decided to study both the effect of fluoxetine monotherapy and that of fluoxetine co-administered with acetylsalicylic acid on lipid peroxidation and antioxidative defense in patients with the first depressive episode in their life. Method Seventy seven patients with major depressive disorder (MDD), divided into two groups were included in the study. The first group, consisting of 52 patients, received fluoxetine 20 mg, and the second one, in addition to fluoxetine 20 mg, received 150 mg of acetylsalicylic acid. The activity of antioxidative enzymes, copper-zinc superoxide dismutase (CuZnSOD, SOD1), catalase (CAT), glutathione peroxidase (GPSH-x) and the concentration of malonyldialdehyde (MDA) was determined in erythrocytes, whereas the total antioxidant status (TAS) was determined in the plasma. All parameters were measured before and after three month therapy. Results The obtained results indicate a significant decrease in the activity of SOD1, CAT and GSHP-x, as well as in MDA concentration after the combined therapy. Also a significant TAS increase was observed after the combined therapy. The study demonstrated that combined therapy with fluoxetine and ASA is characterized by the same efficacy and clinical safety as fluoxetine monotherapy, resulting additionally in improvement of oxidative stress parameters in the patients treated for depression. Copyright © 2009 John Wiley & Sons, Ltd. [source] An accurate hybrid macro-element with linear displacementsINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN BIOMEDICAL ENGINEERING, Issue 1 2005Xiao-Ping Xie Abstract A hybrid stress quadrilateral macro-element HQM is proposed. Compatible linear displacements are used on its two triangular sub-domains, and a 5-parameter incomplete linear stress mode is suggested. Equivalence to another quadrilateral element HQ4 with compatible isoparametric bilinear displacements is proven. Due to elimination of stress parameters at the element level, the computational cost of HQM/HQ4 is as same as that of Q4. Numerical tests show that the element is accurate, insensitive to mesh distortions, and free from Poisson locking. Copyright © 2004 John Wiley & Sons, Ltd. [source] Detoxification and antioxidant effects of curcumin in rats experimentally exposed to mercuryJOURNAL OF APPLIED TOXICOLOGY, Issue 5 2010Rakhi Agarwal Abstract Curcumin, a safe nutritional component and a highly promising natural antioxidant with a wide spectrum of biological functions, has been examined in several metal toxicity studies, but its role in protection against mercury toxicity has not been investigated. Therefore, the detoxification and antioxidant effects of curcumin were examined to determine its prophylactic/therapeutic role in rats experimentally exposed to mercury (in the from of mercuric chloride-HgCl2, 12,µmol,kg,1 b.w. single intraperitoneal injection). Curcumin treatment (80,mg,kg,1 b.w. daily for 3 days, orally) was found to have a protective effect on mercury-induced oxidative stress parameters, namely, lipid peroxidation and glutathione levels and superoxide dismutase, glutathione peroxidase and catalase activities in the liver, kidney and brain. Curcumin treatment was also effective for reversing mercury-induced serum biochemical changes, which are the markers of liver and kidney injury. Mercury concentration in the tissues was also decreased by the pre/post-treatment with curcumin. However, histopathological alterations in the liver and kidney were not reversed by curcumin treatment. Mercury exposure resulted in the induction of metallothionein (MT) mRNA expressions in the liver and kidney. Metallothionein mRNA expression levels were found to decrease after the pre-treatment with curcumin, whereas post-treatment with curcumin further increased MT mRNA expression levels. Our findings suggest that curcumin pretreatment has a protective effect and that curcumin can be used as a therapeutic agent in mercury intoxication. The study indicates that curcumin, an effective antioxidant, may have a protective effect through its routine dietary intake against mercury exposure. [source] Catechin as an antioxidant in liver mitochondrial toxicity: Inhibition of tamoxifen-Induced protein oxidation and lipid peroxidation,JOURNAL OF BIOCHEMICAL AND MOLECULAR TOXICOLOGY, Issue 3 2007Heena Tabassum Abstract Tamoxifen (TAM) is a nonsteroidal triphenylethylene antiestrogenic drug widely used in the treatment and prevention of breast cancer. TAM brings about a collapse of the mitochondrial membrane potential. It acts both as an uncoupling agent and as a powerful inhibitor of mitochondrial electron transport chain. The effect of catechin pretreatment on the mitochondrial toxicity of TAM was studied in liver mitochondria of Swiss albino mice. TAM treatment caused a significant increase in the mitochondrial lipid peroxidation (LPO) and the protein carbonyls (PCs). It also caused a significant increase in superoxide radical production. Pretreatment of mice with catechin (40 mg/kg) showed significant protection as demonstrated by marked attenuation of increased oxidative stress parameters such LPO, PCs, and superoxide production. It also restored the decreased nonenzymatic and enzymatic antioxidants of mitochondria. The inhibitory effect of catechin on TAM-induced oxidative damage suggests that it may have potential benefits in prevention of human diseases where reactive oxygen species have some role as causative agents. © 2007 Wiley Periodicals, Inc. J Biochem Mol Toxicol 21:110,117, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/jbt.20167 [source] Melatonin improves oxidative stress parameters measured in the blood of elderly type 2 diabetic patientsJOURNAL OF PINEAL RESEARCH, Issue 3 2009Kornelia K, dziora-Kornatowska Abstract:, An elevated oxidative status in the aging organism may be involved in the development of non-insulin dependent diabetes mellitus (NIDDM). Melatonin, a potent antioxidant agent, is essential for glucose homeostasis and regulation. The aim of this study was to determine the influence of melatonin supplementation on the oxidative stress parameters in elderly NIDDM patients. The malondialdehyde (MDA) concentration, Cu-Zn superoxide dismutase (SOD-1) activity in erythrocytes, the level of nitrate/nitrite in plasma and morning melatonin concentration and oxidase activity of ceruloplasmin (Cp) in serum in 15 elderly NIDDM patients at baseline and after the 30 days of melatonin supplementation (5 mg daily) in comparison with levels in 15 healthy elderly volunteers were determined. A significant increase of MDA level and decrease of SOD-1 activity and melatonin concentration were observed in NIDDM patients. Cp oxidase activity and nitrate/nitrite level were similar in both examined groups. Melatonin administration in NIDDM patients resulted in a significant increase in the morning melatonin concentration and SOD-1 activity, and a reduction in the MDA level and Cp oxidase activity. Statistically significant alterations in nitrate/nitrite levels were not observed. These results indicate an improvement of antioxidative defense after melatonin supplementation in the NIDDM individuals and suggest melatonin supplementation as an additional treatment for the control of diabetic complications. [source] A comparative study of different crude extracts of Ocimum sanctum on noise stressPHYTOTHERAPY RESEARCH, Issue 6 2002R. Archana Abstract Our previous studies have shown that the ethanolic extract of Ocimum sanctum (OS) leaves was effective in alleviating the noise stress induced changes. Hence in this study, we have investigated the effectiveness of different types of crude OS extracts on some of the stress parameters after noies stress. The results of this study has shown that the active pinciple responsible for antistressor effect of ethanolic extract is also present in cold homogenised leaf extract of OS also. Hot extracts slightly decrease the potency of the active principle in normalizing corticosteroid level. Copyright © 2002 John Wiley & Sons, Ltd. [source] Oxidative stress parameters during starvation and refeeding periods in Adriatic sturgeon (Acipenser naccarii) and rainbow trout (Oncorhynchus mykiss)AQUACULTURE NUTRITION, Issue 6 2009M. FURNÉ Abstract This work analyses the changes in the redox balance in two fish species: Adriatic sturgeon (Acipenser naccarii) and rainbow trout (Oncorhynchus mykiss) during starvation and refeeding period. The starvation period raised the lipid peroxidation (thiobarbituric-acid-reacting substances) levels in liver and blood, while a decline occurred in the antioxidant enzymatic activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPX) and glutathione reductase (GR) in both fish species. In liver, after the refeeding period, SOD activity recovered in both species, whereas CAT activity recovered only in trout. Furthermore, in both tissues of the two species, the lipid peroxidation levels remained high after 2 months of refeeding. In white muscle and heart, the lipid peroxidation levels indicate that these tissues did not undergo oxidative stress during the 72-day period. During starvation, in the muscle of both fish the fall in the lipid peroxidation level coincided with a rise in CAT, GPX and GR. The refeeding period in this tissue raised the lipid peroxidation level, and the enzymatic activities reached the values of the first point of starvation. In heart, no oxidative damage was detected during starvation in either species. The CAT and SOD activities increased during the starvation period only in trout. [source] Amelioration of Cyclosporine A-Induced Renal, Hepatic and Cardiac Damages by Ellagic Acid in Rats,BASIC AND CLINICAL PHARMACOLOGY & TOXICOLOGY, Issue 2 2008Abdurrauf Yüce Cyclosporine A also causes a dose-related decrease in body functions in experimental animals and human beings. The generation of reactive oxygen species has been implicated in cyclosporine A-induced dysfunctions. The aim of this study was to determine the effects of ellagic acid on cyclosporine A-induced alterations in the kidney, liver and heart oxidant/antioxidant system. The control group was treated with placebo and subcutaneous injection of 0.5 ml isotonic saline + 0.5 ml slightly alkaline solution for 21 days. The cyclosporine A group received a subcutaneous injection of cyclosporine A (15 mg/kg) + 0.5 ml slightly alkaline solution for 21 days. The ellagic acid group was treated with a subcutaneous injection of 0.5 ml isotonic saline + ellagic acid (10 mg/kg) for 21 days. The cyclosporine A plus ellagic acid group received a subcutaneous injection of cyclosporine A + ellagic acid for 21 days. Ellagic acid and slightly alkaline solution were administered by gavage. The rats were killed at the end of the treatment period. Malondialdehyde (MDA) and reduced glutathione (GSH) levels, glutathione peroxidase (GSH-Px) and catalase (CAT) activities were determined in kidney, liver and heart tissues. While administration of cyclosporine A increased the MDA levels in kidney, liver and heart tissues, it decreased the GSH, GSH-Px and CAT in these samples when compared to the control group. However, the simultaneously administration of ellagic acid markedly normalized the cyclosporine A-induced liver and heart MDA levels, liver CAT activities and GSH-Px activities of all samples. Cyclosporine A caused marked damages in the histopathological status of kidney, liver and heart tissues, which were partially ameliorated by ellagic acid administration. In conclusion, ellagic acid may be used in combination with cyclosporine A in transplantation treatment to improve the cyclosporine A-induced oxidative stress parameters and other adverse effects. [source] The protective and healing effects of a natural antioxidant formulation based on ubiquinol and Aloe vera against dextran sulfate-induced ulcerative colitis in ratsBIOFACTORS, Issue 1-4 2003Ludmila Korkina Abstract Oxygen/nitrogen reactive species (ROS/RNS) are currently implicated in the pathogenesis of ulcerative colitis, drawing attention on the potential prophylactic and healing properties of antioxidants, scavengers, chelators. We evaluated the possible protective/curative effects of a natural antioxidant preparation based on Aloe vera and ubiquinol, against intestinal inflammation, lesions, and pathological alterations of the intestinal electrophysiological activity and motility, in a rat model of DSS-induced colitis. 5% dextrane sulfate (DDS) (3 days), followed by 1% DSS (4 days) was administered in drinking water. The antioxidant formulation (25 mg/kg) was delivered with a pre-treatment protocol, or simultaneously or post-colitis induction. Spontaneous and acetylcholine-stimulated electrical activity were impaired in the small intestine and in distal colon, upon exposure to DSS only. Severe inflammation occurred, with increased myeloperoxidase activity, and significant alterations of the oxidant/antioxidant status in colonic tissue and peritoneal cells. Lipoperoxidation, superoxide production, glutathione peroxidase and glutathione-S-transferase activities, and reduced glutathione content increased, whilst superoxide dismutase and catalase activities were sharply suppressed in colon tissue. ROS/RNS formation in peritoneal cells was strongly inhibited. Inflammation, electrical/mechanical impairment in the gut, and a great majority of oxidative stress parameters were improved substantially by pre-treatment with the antioxidant preparation, but not by simultaneous administration or post-treatment. [source] Preliminary Results of In-situ Stress Measurements along the Longmenshan Fault Zone after the Wenchuan Ms 8.0 EarthquakeACTA GEOLOGICA SINICA (ENGLISH EDITION), Issue 4 2009Manlu WU Abstract: Four months after the Wenchuan Ms 8 earthquake in western Sichuan, China, in situ stress measurements were carried out along the Longmenshan fault zone with the purpose of obtaining stress parameters for earthquake hazard assessment. In-situ stresses were measured in three new boreholes by using overcoring with the piezomagnetic stress gauges for shallow depths and hydraulic fracturing for lower depths. The maximum horizontal stress in shallow depths (,20 m) is about 4.3 MPa, oriented N19°E, in the epicenter area at Yingxiu Town, about 9.7 MPa, oriented N51°W, at Baoxing County in the southwestern Longmenshan range, and about 2.6 MPa, oriented N39°E, near Kangding in the southernmost zone of the Longmenshan range. Hydraulic fracturing at borehole depths from 100 to 400 m shows a tendency towards increasing stress with depth. A comparison with the results measured before the Wenchuan earthquake along the Longmenshan zone and in the Tibetan Plateau demonstrates that the stress level remains relatively high in the southwestern segment of the Longmenshan range, and is still moderate in the epicenter zone. These results provide a key appraisal for future assessment of earthquake hazards of the Longmenshan fault zone and the aftershock occurrences of the Wenchuan earthquake. [source] Effects of a selective Rho-kinase inhibitor Y-27632 on oxidative stress parameters in acute dichlorvos poisoning in ratsCELL BIOCHEMISTRY AND FUNCTION, Issue 7 2008N. Gunay Abstract This study examined the effects of Y-27632, a selective Rho-kinase inhibitor, on organophosphate-induced acute toxicity in rats. Rats were randomly divided into four groups as control (corn oil), dichlorvos (30,mg,kg,1 i.p.), 1 and 10,mg,kg,1 Y-27632,+,dichlorvos groups. Cholinergic signs (fatigue, tremor, cyanosis, hyper-secretion, fasciculations) were observed in all the rats in the dichlorvos group and the mortality rate was 50%. No cholinergic findings and deaths were observed in the control and Y-27632 groups. Plasma cholinesterase activities were suppressed with dichlorvos and these reductions were attenuated with Y-27632 pretreatment. There was a marked increase in plasma malondialdehyde level in the dichlorvos group, but Y-27632 pretreatment abolished this elevation. Dichlorvos markedly depressed cardiac paraoxonase activity, but these changes were not markedly modified with Y-27632. Total antioxidant capacities, total oxidant status, oxidative stress index, total free sulfhydryl groups and catalase activities in plasma and cardiac tissues were not markedly different between the groups. No significant changes were observed with cardiac myeloperoxidase activities or plasma arylesterase and ceruloplasmin activities. In conclusion, our results suggest that Rho-kinase pathway is involved in organophosphate intoxication, and a decrease in cardiac paraoxonase activities may play a role in the pathogenesis of acute organophosphate poisoning in rats. Copyright © 2008 John Wiley & Sons, Ltd. [source] INTRAPERITONEAL GLYCEROL INDUCES OXIDATIVE STRESS IN RAT KIDNEYCLINICAL AND EXPERIMENTAL PHARMACOLOGY AND PHYSIOLOGY, Issue 8 2008Elenara Rieger SUMMARY 1Glycerol has been used for the treatment of intracranial hypertension, cerebral oedema and glaucoma. Experimentally, intramuscular administration of hypertonic glycerol solution is used to produce acute renal failure. In this model, glycerol causes rhabdomyolysis and myoglobinuria, resulting in the development of renal injury. The pathogenesis is thought to involve vascular congestion, the formation of casts and oxidative stress. However, the effect of glycerol itself independent of rhabdomyolysis has not been investigated. Therefore, the aim of the present study was to investigate the effects of i.p. glycerol on some biochemical and oxidative stress parameters in the kidney of young rats. 2Rats received 10 mL/kg, i.p., hypertonic glycerol solution (50% v/v) or saline (NaCl 0.85 g%) followed by 24 h water deprivation. Twenty-four hours after the administration of glycerol, rats were killed. Creatinine levels and the activity of creatine kinase (CK) and lactate dehydrogenase (LDH) were determined in the plasma. In addition, CK, pyruvate kinase and LDH activity and oxidative stress parameters (free radical formation, lipid peroxidation and protein carbonylation) were measured in renal tissue. 3Glycerol did not alter plasma CK activity and increased plasma creatinine levels, suggesting renal insufficiency and the absence of rhabdomyolysis. Renal CK and pyruvate kinase activity was decreased, suggesting diminution of energy homeostasis in the kidney. Plasma and renal LDH activity was decreased, whereas the formation of free radicals, lipid peroxidation and protein carbonylation were increased, suggesting oxidative stress. 4These results are similar to those described after the intramuscular administration of glycerol. Therefore, it is possible that glycerol may provoke renal lesions by mechanisms other than those induced by rhabdomyolysis. [source] BEHAVIOUR OF THE ANTI-OXIDANT DEFENCE SYSTEM AND HEME OXYGENASE-1 PROTEIN EXPRESSION IN FRUCTOSE-HYPERTENSIVE RATSCLINICAL AND EXPERIMENTAL PHARMACOLOGY AND PHYSIOLOGY, Issue 8 2006Ariel H Polizio SUMMARY 1Addition of fructose to a rat diet for various periods of time leads to hypertension, hyperinsulinaemia and dyslipidaemia and provides a model for testing oxidative stress parameters in the animals. 2In the present study, oxidative stress generation, the soluble and enzymatic defence system and heme oxygenase-1 (HO-1) protein expression were investigated in the heart, liver and kidney of rats fed fructose for a period of 1 or 8 months. 3Compared with the control group, fructose-hypertensive rats showed increased in lipid peroxidation only in the heart after both 1 and 8 months of fructose treatment. Changes in the behaviour of the soluble and enzymatic defence system and HO-1 protein expression were different depending on the organ. Increased or unaltered activities of anti-oxidant enzymes were found in the liver and kidney, respectively. Induction of HO-1 prevented the generation of oxidative stress in the liver, where the activity of anti-oxidant defence enzymes was not reduced. Increased expression of HO-1 protein was not able to prevent the generation of oxidative stress in the heart, where fructose treatment diminished the activity of anti-oxidant enzymes. 4The results of the present study demonstrate that upregulation of HO-1 may prevent the generation of oxidative stress only when the anti-oxidant defence system is still operative. [source] | |||||||||||||||||||