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Öğe Correlations between event-related potential components and nitric oxide in maximal anaerobic exercise among sportsmen trained at various levels(Taylor & Francis Ltd, 2005) Duzova, H; Özisik, HI; Polat, A; Emre, MH; Gullu, EPhysical exercise has influence on all organs except its effects oil the central nervous system have not been fully elucidated. This study attempts to determine whether the degree of training could affect the response to physical stress by comparing the three groups of males in different levels of the physical fitness. Serum samples from high (n = 11), moderate (n = 10), and low physical activity sportsmen (n = 10) were collected to determine nitrite/nitrate levels before and after carrying out an anaerobic maximal exercise test. All oddball paradigm of auditory stimuli was used to evoke the N200 and P300 before and after the exercise. The amplitude of the N200 decreased significantly after anaerobic maximal exercise compared to the values of the recorded pre-exercise at Fz area in high physical activity group. There was a negative correlation between event-related potentials component and both nitrite/mtrate serum level changes and the heart rate changes in low physical activity subjects. However. in high and moderate physical activity groups, these relationships were positive.Öğe Effects of training period on haemorheological variables in regularly trained footballers(Bmj Publishing Group, 2005) Karakoc, Y; Duzova, H; Polat, A; Emre, MH; Arabaci, IObjective: To investigate the effects of one football training period on haemorheological variables in regularly trained footballers. Method: Ten subjects were randomly selected from the reserve team of a football club in the Turkish Premier League. During the last week of the football season, one day before a standard training session and two days after the previous league match, venous blood samples were taken (pre-exercise). After 90 minutes of standard training, further blood samples were taken (post-exercise). Blood lactate, blood viscosity, plasma fibrinogen, blood clotting time, acid-base variables, and plasma Na+, K+, and Ca2+ were determined. Results: Haemoglobin, packed cell volume, and mean corpuscular volume were all significantly decreased, whereas white blood cells and platelets were both increased after training. Blood viscosity decreased but the reduction was not significant. Blood lactate, plasma glucose, and Na+ content were significantly increased, but standard bicarbonate, actual bicarbonate, and Ca2+ were significantly decreased. Blood clotting time had shortened significantly after training. Blood viscosity was inversely correlated with plasma glucose concentration (r = -0.48 and p = 0.032). Conclusions: The results show that blood viscosity tends to decrease as the result of this type of training. This is due to a reduction in packed cell volume and mean corpuscular volume. The increased blood lactate does not have an adverse effect on the blood of these subjects because protective mechanisms develop with regular training throughout the season.Öğe Protective effect of aminoguanidine against nephrotoxicity induced by amikacin in rats(Springer, 2004) Parlakpinar, H; Koc, M; Polat, A; Vardi, N; Ozer, MK; Turkoz, Y; Acet, AAminoglycoside antibiotics have long been used in antibacterial therapy. Despite their beneficial effects, aminoglycosides have considerable nephrotoxic and ototoxic side effects. It has been reported that reactive oxygen radical species (ROS) play role in the pathophysiology of aminoglycosides-induced nephrotoxicity. Aminoguanidine (AG) is an effective antioxidant and free radical scavenger which has long been known to protect against nephrotoxicity. We investigated the effects of AG on amikacin (AK)-induced changes of renal malondialdehyde (MDA), glutathione (GSH), blood urea nitrogen (BUN), serum creatinine (Cr) and albumin (Alb) which are used to monitor the development of renal tubular damage. Morphological changes in the kidney were also examined using light microscopy. A total of 21 rats were equally divided into three groups which were: (1) injected with saline, (2) injected with AK, and (3) injected with AK + AG, respectively. AK administration to control rats increased renal MDA and decreased GSH levels. AG administration before AK injection caused significant decreases in MDA and increases in GSH levels in kidneys compared to rats treated with AK alone. The serum BUN level increased slightly, Cr and serum Alb did not change as a result of any treatment. AG tended to decrease the level of serum BUN and did not cause any change in Alb or Cr levels. Morphological changes, including glomerular, tubular epithelial alterations and interstitial edema, were clearly observed in AK-treated rats. In addition, AG reversed the morphological damage to the kidney induced by AK. The results show that AG has a protective effect on nephrotoxicity induced by AK and may therefore improve the therapeutic index of AK.Öğe Protective effect of caffeic acid phenethyl ester (CAPE) on myocardial ischemia-reperfusion-induced apoptotic cell death(Elsevier Ireland Ltd, 2005) Parlakpinar, H; Sahna, E; Acet, A; Mizrak, B; Polat, AOcclusion of coronary artery causes cardiomyocyte dysfunction. Reperfusion relieves ischemia by providing cells with metabolites and oxygen, thereby preventing extensive tissue damage. Although reperfusion salvages the myocardium, it also initiates a series of events including myocardial apoptosis and necrosis. The common inducers of apoptosis include reactive oxygen species (ROS). Caffeic acid phenethyl ester (CAPE) is known as an antioxidative, anti-inflammatory effects, may protect myocardial ischemia-reperfusion (MI/R)-induced apoptosis. We have previously reported that CAPE reduced MI/R-induced necrosis. Therefore, this study was focused to investigate protective effect of CAPE on the distinct form of cell death; apoptosis in an in vivo rat model. To produce MI/R, a branch of the descending left coronary artery was occluded for 30 min followed by 2 h reperfusion. ECG changes, blood pressure (BP), and heart rate (HR) were measured before occlusion and continued both occlusion and reperfusion. CAPE (50 mu mol/kg) was given 10 min before ischemia via juguler vein. Extensive formation of DNA strand breaks, the typical biochemical feature of apoptosis, was detected with the use of the terminal deoxynucleotidyl transferase (TdT)-mediated d UTP-biotin nick and labeling (TUNEL) method. Also, cysteine aspartate specific proteinase (caspase)-3 and caspase-9 activities a universal effector of apoptosis, were determined. Trunk blood was extracted to determine the serum contents related to oxidant-antioxidant status. In hemodynamic parameters, there was no significant difference in HR or BP values among any group. CAPE administration had no a significant effect on hemodynamic parameters during ischemia or reperfusion. Control group revealed extensive TUNEL-positive cardiomyocytes especially in free wall of left ventricule, interventiculare septum and nearly apex zone. Intensity of TUNEL-positive cardiomyocytes reduced as a result of CAPE treatment compared to control group in the same sections. Result of the caspase activities was found to correlate with TUNEL evaluation. CAPE also, ameliorated antioxidant status. We propose that CAPE acts in the heart as a potent scavenger of free radicals to prevent the apoptotic effect of I/R. Further studies are needed to elucidate the mechanisms of apoptotic death machinery. (C) 2004 Elsevier Ireland Ltd. All rights reserved.Öğe Protective effect of chelerythrine on gentamicin-induced nephrotoxicity(Wiley, 2006) Parlakpinar, H; Tasdemir, S; Polat, A; Bay-Karabulut, A; Vardi, N; Ucar, M; Yanilmaz, MDespite their beneficial effects, aminoglycosides including gentamicin (GEN) have considerable nephrotoxic side-effects. The toxicity of GEN at the level of the kidney seems to relate to the generation of reactive oxygen species (ROS). ROS have been reported to be involved in the activation of protein kinase C (PKC). The unique structural aspects of PKC cause it to function as a sensor for oxidative stress. It seems likely that the increased NAD(P)H oxidase-derived superoxide (O-2) production is at least in part mediated by PKC. We investigated the effects of chelerythrine, a commonly used PKC inhibitor, on GEN-induced changes of renal malondialdehyde (MDA), nitric oxide (NO) generation, catalase (CAT), superoxide disniutase (SOD), glutathione peroxidase (GSH-Px) activities, glutathione (GSH) content, and serum creatinine (Cr), blood urea nitrogen (BUN) levels. Morphological changes in the kidney were also examined. GEN administration to control rats increased MDA and NO generation but decreased CAT, SOD and GSH-Px activities, and GSH content. Chelerythrine administration with GEN caused significantly decreased MDA, NO generation and increased CAT, SOD and GSH-Px activities, and GSH content when compared with GEN alone. Chelerythrine also significantly decreased serum Cr and BUN levels. Morphological changes in the kidney including tubular necrosis were evaluated qualitatively. Both biochemical findings and histopathological evidence showed that administration of chelerythrine reduced the GEN-induced kidney damage. We propose that chelerythrine acts in the kidney as a potent scavenger of free radicals to prevent the toxic effects of GEN via the inhibition of a PKC pathway. Copyright (c) 2004 John Wiley & Sons, Ltd.Öğe Protective role of caffeic acid phenethyl ester (cape) on gentamicin-induced acute renal toxicity in rats(Elsevier Ireland Ltd, 2005) Parlakpinar, H; Tasdemir, S; Polat, A; Bay-Karabulut, A; Vardi, N; Ucar, M; Acet, AThe toxicity of gentamicin (GEN) in the kidney seems to relate to the generation of reactive oxygen species (ROS). Caffeic acid phenethyl ester (CAPE) has been demonstrated to have antioxidant, free radical scavenger and anti-inflammatory effects. It has been proposed that antioxidant maintain the concentration of reduced glutathione (GSH) may restore the cellular defense mechanisms and block lipid peroxidation thus protect against the toxicity of wide variety of nephrotoxic chemicals. We investigated the effects of CAPE on GEN-induced changes in renal malondialdehyde (MDA), a lipid peroxidation product, nitric oxide (NO) generation, superoxide dismutase (SOD), catalase (CAT) activities, GSH content, blood urea nitrogen (BUN) and serum creatinine (Cr) levels. Morphological changes in the kidney were also examined. A total of 32 rats were equally divided into four groups which were: (1) control, (2) injected with intraperitoneally (i.p.) GEN, (3) injected with i.p. GEN + CAPE and (4) injected with i.p. CAPE. GEN administration to control rats increased renal MDA and NO generation but decreased SOD and CAT activities, and GSH content. CAPE administration with GEN injections caused significantly decreased MDA, NO generation and increased SOD, CAT activities and GSH content when compared with GEN alone. Serum level of BUN and Cr significantly increased as a result of nephrotoxicity. CAPE also, significantly decreased serum BUN and Cr levels. Morphological changes in the kidney due to GEN, including tubular necrosis, were evaluated qualitatively. In addition, CAPE reduced the degree of kidney tissue damage induced by GEN. Both biochemical findings and histopathological evidence showed that administration of CAPE reduced the GEN-induced kidney damage. Our results indicated that CAPE acts in the kidney as a potent scavenger of free radicals to prevent the toxic effects of GEN both at the biochemical and histological level. Thus, CAPE could be effectively combined with GEN treatment. (C) 2004 Elsevier Ireland Ltd. All rights reserved.Öğe Renal antioxidant status in rats with hypertension induced by N sup omega nitro-L-arginine methyl ester(Karger, 2002) Fadillioglu, E; Erdogan, H; Polat, A; Emre, MHNitric oxide (NO) has a role in the etiopathogenesis of hypertension. Relaxation of vascular smooth muscles is failed when NO production is reduced leading to increased vascular peripheral resistance. N sup omega nitro-L-arginine methyl ester (L-NAME) is one of the inhibitors of NO production. The aim of this study was to investigate oxidant-antioxidant systems of renal tissue in rats with hypertension induced by L-NAME. Rats were divided into three groups: control group and study groups treated with 100 or 500 mg/l L-NAME in drinking water for 15 days. The activities of catalase (CAT), glutathione peroxidase (GSH-Px) and superoxide dismutase (SOD), and the levels of malondialdehyde (MDA) and NO were studied in the renal tissue after hypertension induction. Arterial blood pressure was increased in both L-NAME groups. CAT activity of 500-mg L-NAME group was higher than control. GSH-Px activity of 500-mg L-NAME group was decreased compared with 100-mg ones. NO level was lower in 500-mg L-NAME group than control. MDA levels in both L-NAME groups were decreased compared with control. In conclusion, hypertension was induced with oral L-NAME treatment. Increased CAT activity was compensated with decreased GSH-Px activity in 500-mg L-NAME group. Both study groups were protected from lipid peroxidation with NO inhibition.Öğe Risk factors for depression in postnatal first year, in eastern Turkey(Oxford Univ Press, 2002) Inandi, T; Elci, OC; Ozturk, A; Egri, M; Polat, A; Sahin, TKBackground There are few studies reporting depression in the postnatal period in developing countries. In this study our objective was to evaluate women from eastern Turkey in the postnatal one-year period in order to analyse the risk factors for depression. Methods In this cross-sectional, multi-centre study, we selected a study sample from five eastern provinces. Among 2602 randomly selected women who gave birth within the last year, we included 2514 women in our analysis. The Edinburgh Postnatal Depression Scale was used for the evaluation of depression. Results The percentage of women with high depression scores was 27.2%. Excess risk of depression was associated with several factors including unemployment, low education, poverty, poor family relations, low marital age, lack of medical services, and mental health problems. Conclusions Depression in postnatal women is an important public health problem in the less developed eastern part of Turkey.Öğe Selective endothelin a (ETA) receptor antagonist (BQ-123) reduces both myocardial infarct size and oxidant injury(Elsevier Ireland Ltd, 2006) Ozdemir, R; Parlakpinar, H; Polat, A; Colak, C; Ermis, N; Acet, AObjective: Endothelins (ET) can be considered stress-responsive regulators working in paracrine and autocrine fashion. It has been suggested that elevated levels of ET may be responsible for the low coronary re-flow phenomena. Ischemia-reperfusion (I/R) was shown to stimulate ET release in rat heart; however, the mechanism(s) of this effect has not been clarified. Therefore, this study was focused to investigate the effect of BQ-123, selective ETA receptor antagonist, on three aspects of myocardial ischemia-reperfusion (MI/R) injury: hemodynamic parameters, infarct size and oxidant-antioxidant status in the absence and presence of ET-1 in an vivo rat model. Methods and results: To produce MI/R, a branch of the descending left coronary artery was occluded for 30 min followed by 2 h reperfusion. ECG changes, blood pressure (BP), and heart rate (HR) were measured before occlusion and continued both occlusion and reperfusion. Forty rats were randomly assigned to five groups equally: (1) sham-operated rats without coronary ligation, (2) I/R group, (3) I/R + BQ-123-treated group (10 mu g/kg/min i.v.), (4) I/R + ET-treated group (25 ng/kg/min i.v.), (5) I/R + ET + BQ-123-treated group. The results are expressed as mean +/- S.E.M. In the ET-1 plus I/R group, the ratio between the infarcted area and area at risk 56 +/- 1% was significantly higher than I/R group (49 +/- 1%). In the BQ-123 group with or without exogenous ET-1 treatment in I/R group, this ratio was significantly lower at 40 +/- 2 and 37 +/- 1%, respectively. As compared to sham group, I/R increased lipid peroxidation whereas decreased nitric oxide (NO), glutathione (GSH), catalase (CAT) and superoxide dismutase (SOD) contents. This decreased antioxidant enzymatic defense could result in aggravated oxidative damage in I/R group rat hearts. ET-1 administration group showed severe oxidative damage. BQ-123 administrations to I/R group with or without ET-1 caused significantly decrease in lipid peroxidation and increased in SOD, CAT activities and NO generation and GSH content when compared with I/R group alone. Conclusions: The most important finding of the present study is that the ET blockade reduced I/R-induced myocardial injury. The mechanism of this reduction was speculated to be a resistance to ischemic injury in the subcellular levels of the myocardium conferred by a reduction of vascular constriction and improvement of imbalance in the antioxidant status. (c) 2005 Elsevier Ireland Ltd. All rights reserved.Öğe Serum selenium response to maximal anaerobic exercise among sportsmen trained at various levels(Wiley-Liss, 2004) Emre, MH; Düzova, H; Sancak, B; Polat, A; Erdogan, H; Yologlu, SSerum selenium (Se) is a constitutional part of both major plasma selenoprotein P and glutathione peroxidase (GSH-Px), a cytoprotective enzyme against the oxidative damage. It is an accepted fact that any case related to oxidative stress increased by physical exercise changes serum Se levels. In this Study serum Se levels were examined in high physical activity (group I). moderate physical activity (group II), and low physical activity (group III) mates undertaking a soccer-training regimen. In addition, Se changes before and after the acute intensive maximal exercise in an anaerobicloading coordination tests among groups I, II, and III soccer players were investigated. For a minimum of 3 months, the players in group I (n = 12), exercising more than 5 It a week. group II (n = 9), exercising less than 5 h but more than 2 h a week, and group III (n = 11), exercising regularly or irregularly less than 2h were examined. Heart rate monitor 220 (heart rate)-age formula wits used to evaluate the maximal exercising test during the procedure. Serum Se was analyzed by atomic absorption spectrophotometry. The difference between groups before and after the exercise was tested by Wilcoxon test, and the difference varying in the groups was tested by Kruskal-Wallis variance analyse. The relation between heart rate and serum Se was tested by Sperman's rank correlation analyses. After maximal physical exercise, the serum selenium level decreased significantly compared with pre-exercise values (P < 0.05) in group I only. III group 1, maximal and pre-exercise heart rates as opposed to pre- and post-exercise serum Se level were negative correlated (P < 0.05). In conclusion, a nutrition regime rich in selenium may be beneficial for both athletes who exercise regularly and in patients with increasing oxidative stress. (C) 2004 Wiley-Liss. Inc.
