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Öğe Alterations in the dimensions of aortopulmonary septum in hypertensive subjects(Nature Publishing Group, 2003) Irmak, MK; Erinc, K; Yazar, F; Uzun, M; Fadillioglu, E; Ozer, MThe neural crest origin of the aortopulmonary septum has led us to investigate the septum for a special function, and we designed the present study to assess the alteration, if any, in the dimensions of the aortopulmonary septum in hypertension. The dimensions of the aortopulmonary septum were measured by echocardiography in 36 hypertensive and 36 age- and sex-matched normotensive subjects. Echocardiographic examination included measurement of the cross-sectional area of the aortopulmonary septum with standard two-dimensional views from the parasternal windows. Standardization of this dimension with appropriate cardiac measurements such as aortic and internal left ventricular diameters was also performed to provide growth-independent estimates of septal size. The average area of the septum in the hypertensive group was 2.18+/-30.391 cm(2), significantly lower than that in the normotensive group (2.370+/-0.415 cm(2)). There were also significant differences in the area of the aortopulmonary septum between the groups when the values were standardized with internal left ventricular diameters. In conclusion, these data confirm that the aortopulmonary septum is smaller in hypertensive than in normotensive humans. This difference might be the result of a possible function of the aortopulmonary septum in blood pressure regulation.Öğe Caffeic acid phenethyl ester changes the indices of oxidative stress in serum of rats with renal ischaemia-reperfusion injury(Wiley, 2001) Özyurt, H; Irmak, MK; Akyol, Ö; Sögüt, SOxygen-derived free radicals have been implicated in the pathogenesis of renal injury after ischaemia-reperfusion. Caffeic acid phencthyl ester (CAPE), an active component of propolis extract, exhibits antioxidant properties. To investigate whether treatment with either CAPE or alpha-tocopherol modifies the levels of the endogenous indices of oxidant stress, we examined their effects on an in vivo model of renal ischaemia-reperfusion injury in rats. CA-PE at 10 mu mol kg(-1) or alpha-tocopherol at 10 mg kg(-1) was administered intraperitoneally before reperfusion. Acute administration of both CAPE and alpha-tocopherol altered the indices of oxidative stress differently in renal ischaemia-reperfusion injury. Copyright (C) 2001 John Wiley & Sons, Ltd.Öğe The effect of caffeic acid phenethyl ester on ischemia-reperfusion injury in comparison with ?-tocopherol in rat kidneys(Springer-Verlag, 2001) Irmak, MK; Koltuksuz, U; Kutlu, NO; Yagmurca, M; Özyurt, H; Karaman, A; Akyol, ÖOxygen-derived free radicals have been implicated in the pathogenesis of renal injury after ischemia-reperfusion. Caffeic acid phenethyl ester (CAPE), an active component of propolis extract, exhibits antioxidant and anti-inflammatory properties. To determine whether CAPE offers any advantage over alpha -tocopherol, we compared their effects on an in vivo model of renal ischemia-reperfusion injury in rats. CAFE at 10 mu mol/kg or alpha -tocopherol at 10 mg/kg was administered intraperitoneally before reperfusion. Acute administration of CAFE suppressed ischemia-reperfusion induced renal lipid peroxidation and tissue injury more than alpha -tocopherol. CAFE may therefore offer a therapeutic advantage in acute injury settings.Öğe Effects of caffeic acid phenethyl ester and alpha-tocopherol on reperfusion injury in rat brain(Wiley, 2003) Irmak, MK; Fadillioglu, E; Sogut, S; Erdogan, H; Gulec, M; Ozer, M; Yagmurca, MOxygen-derived free radicals have been implicated in the pathogenesis of cerebral injury after ischaemia-reperfusion. Caffeic acid phenethyl ester (CAPE), an active component of propolis extract, exhibits antioxidant properties. The purpose of the present study was to investigate the effects of ischaemia and subsequent reperfusion on rat brain and to investigate the effects of two free radical scavengers, CAPE and alpha-tocopherol, on this in vivo model of cerebral injury. Ischaemia was induced by bilateral occlusion of the carotid arteries for 20 min and reperfusion was achieved by releasing the occlusion to restore the circulation for 20 min. Control rats underwent a sham operation. CAPE at 10 mumol kg(-1) or alpha-tocopherol at 25 mumol kg(-1) was administered intraperitoneally before reperfusion. Reperfusion led to significant increase in the activity of xanthine oxidase and higher malondialdehyde levels in the brain. Acute administration of both CAPE and alpha-tocopherol suppressed ischaemia-reperfusion-induced cerebral lipid peroxidation and injury, but CAPE seems to offer a better therapeutic advantage over alpha-tocopherol. Copyright (C) 2003 John Wiley Sons, Ltd.Öğe Effects of electromagnetic radiation from a cellular telephone on epidermal Merkel cells(Blackwell Munksgaard, 2003) Irmak, MK; Oztas, E; Yagmurca, M; Fadillioglu, E; Bakir, BThe number of reports on the effects induced by electromagnetic radiation (EMR) from cellular telephones in various cellular systems is still increasing. Until now, no satisfactory mechanism has been proposed to explain the biological effects of this radiation except a role suggested for mast cells. Merkel cells may also play a role in the mechanisms of biological effects of EMR. This study was undertaken to investigate the influence of EMR from a cellular telephone (900 MHz) on Merkel cells in rats. A group of rats was exposed to a cellular telephone in speech position for 30 min. Another group of rats was sham-exposed under the same environmental conditions for 30 min. Exposure led to significantly higher exocytotic activity in Merkel cells compared with the sham exposure group. This finding may indicate the possible role of Merkel cells in the pathophysiology of the effects of EMR.Öğe Effects of electromagnetic radiation from a cellular telephone on the oxidant and antioxidant levels in rabbits(Wiley, 2002) Irmak, MK; Fadilloglu, E; Güleç, M; Erdogan, H; Yagmurca, M; Akyol, ÖThe number of reports on the effects induced by electromagnetic radiation (EMR) in various cellular systems is still increasing. Until now no satisfactory mechanism has been proposed to explain the biological effects of this radiation. Oxygen free radicals may play a role in mechanisms of adverse effects of EMR. This study was undertaken to investigate the influence of electromagnetic radiation of a digital GSM mobile telephone (900 MHz) on oxidant and antioxidant levels in rabbits. Adenosine deaminase, xanthine oxidase, catalase, myeloperoxidase, superoxide dismutase (SOD) and glutathione peroxidase activities as well as nitric oxide (NO) and malondialdehyde levels were measured in sera and brains of EMR-exposed and sham-exposed rabbits. Serum SOD activity increased, and serum NO levels decreased in EMR-exposed animals compared to the sham group. Other parameters were not changed in either group. This finding may indicate the possible role of increased oxidative stress in the pathophysiology of adverse effect of EMR. Decreased NO levels may also suggest a probable role of NO in the adverse effect. Copyright (C) 2002 John Wiley Sons, Ltd.Öğe Erdosteine prevents doxorubicin-induced cardiotoxicity in rats(Academic Press Ltd- Elsevier Science Ltd, 2003) Yagmurca, M; Fadillioglu, E; Erdogan, H; Ucar, M; Sogut, S; Irmak, MKThe clinical use of doxorubicin (Dxr) is limited by its cardiotoxic effects which are mediated by oxygen radicals. The purpose of this study was to investigate in vivo protective effects of erdosteine, an antioxidant agent because of its secondary active metabolites in vivo, against the cardiotoxicity induced by Dxr in rats. Three groups of male Sprague-Dawley rats (60 days old) were used. Group I was untreated group used as control; the other groups were treated with Dxr (single i.p. dosage of 20 mg kg(-1) b.wt.) or Dxr plus erdosteine (10 mg kg(-1) day(-1), orally), respectively. Erdosteine or oral saline treatment was done starting 2 days before Dxr for 12 days. The analyses were done at the 10th day of Dxr treatment. The protein carbonyl content, the activities of myeloperoxidase, aspartate aminotransferase (AST), lactate dehydrogenase (LDH), and creatine kinase (CK) as well as heart rate and blood pressures were significantly increased in Dxr group in comparison with the other groups. However, pulse pressure was decreased in Dxr group. The body and heart weights were decreased in both Dxr administered groups in comparison with control group. Disorganization of myocardial histology, picnotic nuclei, edema, and increase in collagen content around vessels were seen in the slides of Dxr group, whereas normal myocardial microscopy was preserved in Dxr plus erdosteine group. Collectively, these in vivo hemodynamic, enzymatic and morphologic studies provide an evidence for a possible prevention of cardiac toxicity in Dxr-treated patients. (C) 2003 Elsevier Ltd. All rights reserved.Öğe Protective effects of caffeic acid phenethyl ester on doxorubicin-induced cardiotoxicity in rats(Wiley, 2004) Fadillioglu, E; Oztas, E; Erdogan, H; Yagmurca, M; Sogut, S; Ucar, M; Irmak, MKThe prevention of doxorubicin (DXR)-induced cardiotoxicity may be helpful to improve future DXR therapy. The aim of this study was to investigate the cardio-protective effects of caffeic acid phenethyl ester (CAPE), an antioxidant agent, on DXR-induced cardiotoxicity. Rats were divided into three groups and treated with saline, DXR and DXR + CAPE. Rats were treated with CAPE (10 gmol kg(-1) day(-1) i.p.) or saline starting 2 days before a single dose of DXR (20 mg kg(-1) i.p.). Ten days later, haemodynamic measurements were performed and the hearts were excised for biochemical analyses and microscopic examination. The heart rate and mean blood pressure were higher and the pulse pressure was lower in the DXR group than in the other two groups. The administration of DXR alone resulted in higher myeloperoxidase activity, lipid peroxidation and protein carbonyl content than in the other groups. The activities of superoxide dismutase and catalase were higher in DXR and DXR + CAPE groups than in the saline group. Rats in the DXR + CAPE group had increased catalase activity in comparison with the DXR group and high glutathione peroxidase activity in comparison with the other two groups. There was severe disruption of mitochondrial fine structure in the electron microscopy of the DXR group. In contrast, myocardial microscopy appeared nearly normal in the DXR + CAPE group (as defined at the electron microscopic level). In light of these in vivo haemodynamic, enzymatic and morphological results, we conclude that CAPE pretreatment significantly attenuated DXR-induced cardiac injury, possibly with its antioxidant effects. Copyright (C) 2004 John Wiley Sons, Ltd.Öğe Protein oxidation and lipid peroxidation after renal ischemia-reperfusion injury(Springer, 2006) Erdogan, H; Fadillioglu, E; Yagmurca, M; Uçar, M; Irmak, MKOxygen radicals have roles in the renal ischemia-reperfusion (IR) injury usually encountered in several conditions such as renal transplantation. The aim of this study was to investigate the effects of erdosteine and N-acetylcysteine (NAC) on the oxidant/antioxidant status and microscopy of renal tissues after IR injury. Male Sprague-Dawley rats were randomly assigned to four groups: control untreated rats, IR (30 min ischemia and 120 min reperfusion), IR + NAC (i.p.; 180 mg/kg) and IR + erdosteine (oral; 50 mg/kg/day for 2 days before experiments) groups. After unilateral renal IR, the right kidney was rapidly excised and sectioned vertically into two pieces for microscopic examination and biochemical analysis. Erdosteine and NAC treatment did not cause any significant change in the activity of superoxide dismutase (SOD) in comparison with the IR group, even if the SOD activity increased in IR groups than in the control group. Catalase (CAT) activity was decreased in the IR group in comparison with control and IR + erdosteine groups (P < 0.05), whereas it was higher in the IR + erdosteine group than in the IR + NAC group (P < 0.05). Xanthine oxidase (XO) activity was higher in all the IR-performed groups than in the control group (P < 0.05). Thiobarbituric acid-reactive substances (TBARS) level and protein carbonyl (PC) content were increased after IR injury (P < 0.05). Erdosteine or NAC treatments ameliorated these increased TBARS and PC contents in comparison with the IR group (P < 0.05). Light microscopy of the IR group showed tubular dilatation, tubular necrosis and vacuole formation in epithelial cells. Erdosteine but not NAC apparently reduced the renal tissue damage. The pathological damage score after IR was significantly reduced after erdosteine treatment (P < 0.05), but not after NAC treatment. In conclusion, renal IR resulted in oxidative damage as seen in biochemical lipid peroxidation and protein oxidation results with aggravated tubular necrosis. Erdosteine and NAC treatments improved the biochemical results of IR injury. However, on microscopic evaulations, animals receiving erdosteine showed a great reduction in renal damage when compared with the NAC group.Öğe Testicular nitric oxide levels after unilateral testicular torsion/detorsion in rats pretreated with caffeic acid phenethyl ester(Springer-Verlag, 2000) Koltuksuz, U; Irmak, MK; Karaman, A; Uz, E; Var, A; Özyurt, H; Akyol, ÖNitric oxide (NO) plays an important role in modulating blood flow in normal and in several pathological conditions, and its levels seem to change with ischemia-reperfusion injuries. Caffeic acid phenethyl ester (CAPE), an active component of propolis, exhibits antioxidant properties. This experimental study was designed to determine the changes in NO levels and the effect of CAPE on NO levels after testicular torsion/ detorsion in rats. Thirty-five adult male albino rats were divided into four groups: sham operation (n = 8), torsion (n = 9), saline/detorsion (n = 9), and CAPE/detorsion (n = 9). Rats in the sham operation group were killed after the testes were handled without torsion. Rats in the torsion group were killed after 720 degrees clockwise testicular torsion for 2 h. CAPE was administered 30 min before detorsion in the CAPE/detorsion group and saline was administered in the saline/detorsion group. After 4 h of testicular detorsion in both of these groups, the rats were killed and bilateral orchiectomy was performed to determine the tissue levels of NO. The level of NO in the torsion group (113.77 +/- 33.18 nmol/g protein) was significantly higher than that of the sham operation group (64.53 +/- 29.64 nmol/g protein). In the saline/detorsion group, the NO level (31.26 +/- 12.58 nmol/g protein) was significantly lower than in the torsion and sham operation groups. CAPE administration in the CAPE/detorsion group seemed to raise the NO level (72.63 +/- 23.87 nmol/g protein) above the level of the sham operation group. Contralateral testes were not affected by the torsion/detorsion processes performed on the ipsilateral testes. These results show that NO levels increase with torsion and decrease with detorsion. CAPE administration seems to increase tissue NO levels and this may be important for protecting the testes from torsion/detorsion injuries.
