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Öğe The bronchoalveolar epithelial permeability in house painters as determined by Tc-99m DTPA aerosol scintigraphy(Springer, 2003) Kaya, M; Salan, A; Tabakoglu, E; Aydogdu, N; Berkarda, SPurpose: Isocyanates are highly reactive chemicals used in a number of industries including paints. Therefore, house painters are known to be at risk for occupational exposure to isocyanates. Our objectives in this study were: (1) to investigate the possible effects of isocyanate exposition on the bronchoalveolar epithelial permeability in house painters by using Tc-99m DTPA radioaerosol lung scintigraphy; (2) to assess whether or not some differences exist between asthmatic and non-asthmatic house painters, and (3) to determine the relationship between Tc-99m DTPA radioaerosol lung scintigraphy and the spirometric measurements, and the work duration of house painters. Materials and Methods: Ten non-smoking house painters (28.8 +/- 8.8 yrs) and ten healthy volunteers underwent Tc-99m DTPA radioaerosol lung scintigraphy. Following inhalation of radiotracer through a nebulizer for 5 minutes, dynamic scintigrams (1 frame/min, up to 10 min) were taken from both lungs. ROI's were drawn over the both lung area, and time-activity curves were obtained, from which the half-time (T-1/2) of Tc-99m DTPA clearance was calculated. Spirometric lung function test was measured in all house painters. Results: Mean T1/2 values (min +/- SD) were 93.74 +/- 32.79 for house painters, and 90.96 +/- 40.02 for control subjects. There was no significant difference in T1/2 values of Tc-99m DTPA clearance between house painters and controls, and between asthmatic and non-asthmatic house painters as well. No correlation was observed between Tin values of Tc-99m DTPA clearance and spirometric measurements. In house painters, there was a positive correlation between T1/2 values of Tc-99m DTPA clearance and work duration (r = 0.73, p = 0.016). Conclusions: Our findings indicate that in house painters, occupational exposure to isocyanates has no effect on bronchoalveolar epithelial permeability, and the rate of Tc-99m DTPA clearance shows no difference between asthmatic and non-asthmatic house painters. The positive correlation between the rate of Tc-99m DTPA clearance and work duration needs to be confirmed in larger cohorts.Öğe Comparison of chemopreventive effects of Vitamin E plus selenium versus melatonin in 7,12-dimethylbenz(a) anthracene-induced mouse brain damage(Elsevier Sci Ltd, 2004) Batcioglu, K; Karagözler, AA; Ozturk, IC; Genc, M; Bay, A; Ozturk, F; Aydogdu, NIn this work, the protective effect of Vitamin E plus selenium (Vit E + Se) and melatonin against 7,12-dimethylbenz(a)anthracene (7,12DMBA)-induced changes in superoxide dismutase (SOD), glutathione peroxidase (GSHPx), catalase (CAT) and carbonic anhydrase (CA) activities and malonedialdehyde (MDA) levels of mouse brain were compared. 12-month old mice were divided into four groups each including 10 animals. The first group served as control group. The second group was treated with 7,12-DMBA (20 mg/(kg day)). The third group was treated with 7,12-DMBA and Vitamin E (90 mu g/(individual day)) and selenium (1.8 mu g/(individual day)) simultaneously. The fourth group was treated with 7, 12-DMBA and melatonin (4.2 mg/(kg day)) simultaneously. Treatment continued for 21 days after which the mice were sacrificed and brain homogenates were prepared. 7,12-DMBA treated group exhibited significantly decreased levels of brain SOD, GSHPx, CAT and CA activities and increased MDA levels as compared to control. Vitamin E + Se fully or partially restored enzyme inhibition except for SOD. Lipid peroxidation was also reduced in Vitamin E + Se treated group. Melatonin provided a better protection for SOD, GSHPx and CAT, and a plausible protection for CA activity. Protection against lipid peroxidation measured as MDA in melatonin treated group was appreciable although slightly lesser than the protection provided by Vitamin E + Se. The results imply that Vitamin E + Se and melatonin both provide chemoprevention against 7,12-DMBA-induced oxidative stress in mouse brain. (c) 2004 International Society for Preventive Oncology. Published by Elsevier Ltd. All rights reserved.Öğe Comparison with clearance of Tc-99m DTPA aerosol, and CO diffusing capacity, and lung function test in house painters(Springer-Verlag, 2001) Kaya, M; Salan, A; Tabakoglu, E; Aydogdu, N; Yüksel, M; Salihoglu, YS; Yigitbas, ON[Abstract Not Available]Öğe Effects of caffeic acid phenethyl ester on glycerol-induced acute renal failure in rats(Wiley, 2004) Aydogdu, N; Atmaca, G; Yalcin, O; Batcioglu, K; Kaymak, K1. Free radicals and nitric oxide (NO) play a crucial role in the pathogenesis of myoglobinuric acute renal failure (ARE). The aim of the present study was to investigate the effects of caffeic acid phenethyl ester (CAPE), an anti-oxidant, on the myoglobinuric ARF induced by intramusculer hypertonic glycerol injection. 2. Thirty rats were divided equally into three groups. Rats in group I were given saline and those in groups 2 and 3 were injected with glycerol (10 mL/kg, i.m.). Concomitant and 24 It after glycerol injection, CAPE (10 mumol/kg, i.p.) was administered to group 3 rats. Forty-eight hours after glycerol injection, blood samples and kidney tissues of rats were taken under anaesthesia. 3. Plasma concentrations of urea, creatinine, malondialdehyde (MDA) and NO were determined, as were superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) activities and MDA levels in kidney tissues. Kidney morphology was also investigated. 4. In the group receiving CAPE, although SOD enzyme activity was found to be increased, we failed to find any protective effect of CAPE on other parameters investigated. Moreover, although CAPE significantly decreased NO levels, it increased plasma concentrations of urea and MDA. 5. We suggest that the effect of CAPE in decreasing NO concentrations may further increase the renal ischaemia in this model. Thus, CAPE may have a worsening rather than beneficial effect under these conditions in this model of ARF.Öğe Effects of exogenous melatonin on myoglobinuric acute renal failure in the rats(Taylor & Francis Ltd, 2004) Aydogdu, N; Atmaca, G; Yalcin, O; Batcioglu, K; Kaymak, KFree oxygen radicals and nitric oxide (NO) play a crucial role in the pathogenesis of myoglobinuric acute renal failure (ARF). In this study, we aimed to investigate the effect of melatonin, a potent free radical scavenger, on the myoglobinuric ARF formed by injecting hypertonic glycerol intramuscularly (im). The rats were randomly divided into 4 Groups. Rats in Group 1 were given saline and those in Groups 2, 3, and 4 were injected with glycerol (10 mL/kg) im. Concomitant and 24 hours after glycerol injection Group 3 (5 mg/kg) and Group 4 (10 mg/kg) were administrated melatonin intraperitoneally. Forty-eight hours after the glycerol injection, the blood and kidneys of the rats were taken under anesthesia. Kidney morphology and the levels of urea, creatinine and nitric oxide metabolites (NOx) in the plasma and the enzyme activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) and the level of malondialdehyde (MDA) in the kidney were determined. In both groups of melatonin administration, there was no protective effect of melatonin. Moreover, melatonin significantly decreased the level of NO. As a result, we suggest that the decreasing effect of melatonin on NO, which is a strong vasodilatator, may further increase the renal ischemia in this model. Thus, melatonin may have worsening rather than beneficial effects on myoglobinuric ARF.Öğe Effects of N-acetylcysteine on arginase, ornithine and nitric oxide in renal ischemia-reperfusion injury(Academic Press Ltd- Elsevier Science Ltd, 2004) Erbas, H; Aydogdu, N; Kaymak, KBackground: Renal ischemia-reperfusion (I/R) is a complex syndrome involving several mechanisms such as renal vasoconstrictions, extensive tubular damage and glomerular injury. N-Acetylcysteine (NAC), a potent antioxidant by itself, may serve as a precursor for glutathione synthesis. The aim of this study was to investigate the possible effects of NAC on liver and kidney tissue arginase activity, ornithine and plasma nitric oxide levels during the I/R injury of kidney. Methods: Twenty-four female Sprague-Dawley rats divided into three groups: group 1; was given saline intraperitoneally (i.p.). Saline to group 2 and NAC (300 mg kg(-1)) to group 3 were injected i.p. 30 min before induction of ischemia. Groups 2 and 3; subjected to bilateral renal ischemia (60 min) followed by reperfusion (24 h). After the reperfusion period, the rats were sacrificed and liver and kidney tissue arginase activities, ornithine and plasma nitric oxide (NO) levels were determined. Results: NAC had an increasing effect on both of liver and kidney tissue arginase activities and ornithine levels while decreasing plasma NO concentration. Conclusion: The stimulatory effect of NAC on arginase activity may result in an inhibition of the plasma NO level. Moreover, it could be possible that one of the protective mechanisms of NAC might be through the stimulation on the both liver and kidney tissue ornithine levels. (C) 2004 Elsevier Ltd. All rights reserved.Öğe L-carnitine inhibits ethanol-induced gastric mucosal injury in rats(Springer Heidelberg, 2005) Dokmeci, D; Akpolat, M; Aydogdu, N; Doganay, L; Turan, FNL-carnitine is a quaternary amine that is essential for the normal oxidation of long-chain fatty acids by mitochondria. It is known that L-carnitine and its derivatives prevent the formation of reactive oxygen species, scavenge free radicals and protect cells from peroxidative stress. Oxygen-derived free radicals and lipid peroxidation products play a critical role in the pathogenesis of ethanol-induced gastric mucosal injury. The aim of the present study was to determine the effect of L-camitine on lipid peroxidation induced by ethanol in the rat stomach. In our study, gastric mucosal injury was induced by the intragastric administration of 1 ml of absolute ethanol. Test compounds were given to rats by gavage 30 min before the ethanol administration. The animals were killed 60 min after the administration of ethanol. The stomach of each animal was removed. Mucosal damage was evaluated by macroscopic examination, histological analysis and by measurement of lipid peroxidation and glutathione activity. The intragastric administration of ethanol induced hyperemia and hemorrhagic erosions in the rat stomachs. L-camitine significantly prevented gastric ulcerogenesis induced by ethanol and decreased the ulcer index. Plasma and gastric lipid peroxidation that was increased significantly by ethanol was decreased after treatment with L-camitine. Ethanol treatment decreased significantly the gastric glutathione levels, and pretreatment with L-camitine increased them significantly. Based on these data, the beneficial effects of L-camitine on ethanol-induced gastric mucosal injury may be attributed to its antiperoxidative effects.Öğe Lipid peroxidation and antioxidant status in stomach cancer(Taylor & Francis Inc, 2006) Batcioglu, K; Mehmet, N; Ozturk, IC; Yilmaz, M; Aydogdu, N; Erguvan, R; Uyumlu, BBackground: Considerable evidences have linked oxidative damage and cancer. In this article, superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSHPx) activities, and malondialdehyde (MDA) and nitric oxide metabolites' levels (NOx) were investigated in patients with stomach cancer. Methods: All measurments were done by spectrophotometric techniques. Results: We observed a significant decrease in the activities of SOD and CAT in tumour tissues when compared with control tissues. The different of GSHPx activities and NO metabolite' levels were not statistically significant. MDA levels were significantly increased. Conclusions: We conclude that increased MDA levels and decreased antioxidant enzyme activities can be valuable parameters in assessing the possible risk of cancer.Öğe Protective effects of L-carnitine on myoglobinuric acute renal failure in rats(Wiley, 2006) Aydogdu, N; Atmaca, G; Yalcin, O; Taskiran, R; Tastekin, E; Kaymak, K1. Muscle injury (rhabdomyolysis) is one of the causes of acute renal failure (ARF). Iron, free radicals and nitric oxide (NO) play a critical role in the pathogenesis of glycerol-induced myoglobinuric ARF. L-Carnitine is an anti-oxidant and prevents the accumulation of end-products of lipid peroxidation. Therefore, the aim of the present study was to investigate the effects of L-carnitine on myoglobinuric ARF induced by intramuscular (i.m.) hypertonic glycerol injection. 2. Sprague-Dawley rats were divided into three groups. Rats in group 1 (n = 8) were given saline, whereas those in groups 2 (n = 10) and 3 (n = 10) were injected with glycerol (10 mL/kg, i.m.). Concomitant with and 24 h after glycerol injection, L-carnitine (200 mg/kg, i.p.) was administered to group 3 rats. Forty-eight hours after glycerol injection, blood samples and kidney tissues were taken from anaesthetised rats. 3. Plasma creatine kinase (CK) activity, urea, creatinine and NO levels, as well as kidney tissue superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) enzyme activity and malondialdehyde (MDA) and glutathione (GSH) levels, were determined. In the kidney tissue, histopathological changes and iron accumulation in the tubular epithelium were also investigated. 4. Glycerol treatment caused severe ARF: a marked renal oxidative stress, significantly increased CK activity, urea and creatinine levels and decreased plasma NO levels. Histopathological findings in group 2 rats confirmed that there was renal impairment by cast formation and tubular necrosis and a marked increase in iron accumulation in the tubular epithelium. All these factors were significantly improved by L-carnitine supplementation. 5. These results may indicate that L-carnitine treatment protects against functional, biochemical and morphological damage and iron accumulation in glycerol-induced myoglobinuric ARF in rats. In this model, the protective effect of L-carnitine treatment may provide a new insight into the treatment of rhabdomyolysis-related ARF.