Person: YÜKSEL, MERAL
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YÜKSEL
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MERAL
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Publication Metadata only The effect of magnesium and vitamin E pre-treatments on irradiation-induced oxidative injury of cardiac and pulmonary tissues in rats: a randomized experimental study(TURKISH SOC CARDIOLOGY, 2012) ATASOY, BESTE MELEK; Atasoy, Beste M.; Ozgen, Zerrin; Bostanci, Korkut; Yuksel, Meral; Ozen, Zeynep; Ibrahimov, Roman; Abacioglu, UfukObjective: The aim of this study was to investigate the effect of pre-treatment with the free radical scavenging molecules, magnesium and vitamin E, on lipid peroxidation to limit radiation-induced heart and lung injury. Methods: Female Sprague-Dawley rats were divided into 4 groups by a simple randomization method as saline-treated control (n=4), saline-treated irradiated (IR; n=6), magnesium sulphate-treated irradiation (IR) (Mg+IR; n=6) and vitamin E-treated IR (vit E+IR; n=6), respectively. The animals were given either saline, Mg (600mg/kg/day) or vit E (100 mg/kg/day) intraperitoneally for five days prior to irradiation. Twelve hours after the fifth injection, animals in irradiation groups were irradiated to 20 Gy using 6 MV photons in linear accelerator. Twenty-four hours later cardiac and lung tissue samples were obtained for determination of myeloperoxidase activity (MPO), malondialdehyde (MDA) levels, and luminol and lucigenin levels measured by chemiluminescence (CL) methods. Results: No significant changes were observed between cardiac and pulmonary MDA and CL results of the experimental groups. However, cardiac and pulmonary MPO activities in the saline-treated IR group were increased as compared to control group (p<0.05 for all), while in the Mg-pretreated and vit E pretreated groups neutrophil infiltration was reduced, reaching to statistical significance only in the Mg-pretreated group (p<0.05). Conclusion: Prophylactic use of magnesium sulfate has limited the infiltration of neutrophils to both the cardiac and pulmonary tissues at the early 24 h of irradiation. However, how limiting neutrophils as the sources of free radicals and inflammatory mediators would alter oxidative stress of heart and lung tissues in the long-term is not clear yet. (Anadolu Kardiyol Derg 2012; 12: 508-14)Publication Open Access Superoxide Anion Production by the Spermatozoa of Men with Varicocele: Relationship with Varicocele Grade and Semen Parameters(KOREAN SOC SEXUAL MEDICINE & ANDROLOGY, 2018) YÜKSEL, MERAL; Alkan, Ilter; Yuksel, Meral; Canat, Halil Lutfi; Atalay, Hasan Anil; Can, Osman; Ozveri, Hakan; Basar, Mehmet MuradPurpose: To investigate the pathophysiological role of superoxide anion and total reactive oxygen species (ROS) production by the spermatozoa of men with varicocele and its relationship with varicocele grade and semen parameters. Materials and Methods: This prospective study included 34 men with grade II-III varicocele, regardless of their fertility status. The control group consisted of 13 healthy men. Semen characteristics were examined according to the 2010 World Health Organization criteria. The swim-up method was used for sperm preparation. Total ROS and superoxide anion production was assayed by luminol-and lucigenin-dependent chemiluminescence (CL), respectively. Results: The men with varicocele had significantly higher total ROS and superoxide anion levels than the healthy control subjects (2.9 +/- 0.4 relative light unit (RLU) vs. 2.4 +/- 0.1 RLU, p=0.001 for luminol-dependent CL and 2.8 +/- 0.4 RLU vs. 2.3 +/- 0.2 RLU, p=0.002 for lucigenin-dependent CL). Cases of grade III varicocele had significantly higher superoxide anion and total ROS levels than grade II cases and control subjects (p<0.001). Superoxide anion and total ROS levels were negatively correlated with all semen parameters. Conclusions: The superoxide anion levels produced by spermatozoa were significantly higher in varicocele patients than in control subjects. ROS production was related to increased varicocele grade, impaired semen concentration, and abnormal morphology in men with varicocele. Our findings suggest that superoxide anion overproduction may be an important step in the cascade of ROS-related damage to spermatozoa, resulting in impaired semen parameters in patients with varicocele.Publication Metadata only Apocynin attenuates testicular ischemia-reperfusion injury in rats(W B SAUNDERS CO-ELSEVIER INC, 2015) ŞİMŞEK, FERRUH; Sener, T. Emre; Yuksel, Meral; Ozyilmaz-Yay, Nagehan; Ercan, Feriha; Akbal, Cem; Simsek, Ferruh; Sener, GokselObjective: This study was designed to examine the possible protective effect of apocynin, a NADPH oxidase inhibitor, against torsion/detorsion (T/D) induced ischemia/reperfusion (I/R) injury in testis. Methods: Male Wistar albino rats were divided into sham-operated control, and either vehicle, apocynin 20 mg/kg-or apocynin 50 mg/kg-treated T/D groups. In order to induce I/R injury, left testis was rotated 720 degrees clockwise for 4 hours (torsion) and then allowed reperfusion (detorsion) for 4 hours. Left orchiectomy was done for the measurement of tissue malondialdehyde (MDA), glutathione (GSH) levels, myeloperoxidase (MPO) activity, and luminol, lucigenin, nitric oxide (NO) and peroxynitrite chemiluminescences (CL). Testicular morphology was examined by light microscopy. Results: I/R caused significant increases in tissue luminol, lucigenin, nitric oxide and peroxynitrite CL demonstrating increased reactive oxygen and nitrogen metabolites. As a result of increased oxidative stress tissue MPO activity, MDA levels were increased and antioxidant GSH was decreased. On the other hand, apocynin treatment reversed all these biochemical indices, as well as histopathological alterations that were induced by I/R. According to data, although lower dose of apocynin tended to reverse the biochemical parameters, high dose of apocynin provides better protection since values were closer to the control levels. Conclusion: Findings of the present study suggest that NADPH oxidase inhibitor apocynin by inhibiting free radical generation and increasing antioxidant defense exerts protective effects on testicular tissues against I/R. The protection with apocynin was more pronounced with high dose. (C) 2015 Elsevier Inc. All rights reserved.Publication Metadata only The antifibrotic drug halofuginone reduces ischemia/reperfusion-induced oxidative renal damage in rats(ELSEVIER SCI LTD, 2013) YEGEN, BERRAK; Cerit, Kivilcim Karadeniz; Karakoyun, Berna; Yuksel, Meral; Ozkan, Naziye; Cetinel, Sule; Dagli, E. Tolga; Yegen, Berrak C.; Tugtepe, HalilAim: The objective of the present study was to evaluate the protective effects of halofuginone against renal ischemia/reperfusion (I/R) injury. Materials and methods: Male Wistar albino rats were unilaterally nephrectomized and the left renal pedicles were occluded for 45 min to induce ischemia and then reperfused for 6 h (early) or for 72 h (late). The rats were treated intraperitoneally with either halofuginone (100 mu g/kg/day) or saline 30 min prior to ischemia and the dose was repeated in the late reperfusion groups. In the sham groups, rats underwent unilateral nephrectomy and were treated at similar time points. The animals were decapitated at either 6 h or 72 h of reperfusion and trunk blood and kidney samples were obtained. Results: I/R injury increased renal malondialdehyde levels, myeloperoxidase activity and reactive oxygen radical levels, and decreased the renal glutathione content. Halofuginone treatment was found to reduce oxidative I/R injury and improve renal function in the rat kidney, as evidenced by reduced generation of reactive oxygen species, depressed lipid peroxidation and myeloperoxidase activity, and increased glutathione levels. Conclusions: The present findings demonstrate the anti-inflammatory and antioxidant effects of halofuginone in renal I/R injury, supporting its potential use where renal I/R injury is inevitable. (C) 2012 Journal of Pediatric Urology Company. Published by Elsevier Ltd. All rights reserved.Publication Metadata only Semen reactive oxygen species levels are correlated with erectile function among chronic prostatitis/chronic pelvic pain syndrome patients(NATURE PUBLISHING GROUP, 2018) YÜKSEL, MERAL; Alkan, Ilter; Yuksel, Meral; Ozveri, Hakan; Atalay, Anil; Canat, Halil Lutfi; Culha, Mehmet Gokhan; Arabaci, Cigdem; Bozkurt, Muammer; Basar, MuradChronic Prostatitis/Chronic Pelvic Pain Syndrome (CP/CPPS) is often associated with erectile dysfunction (ED). However, the underlying pathophysiological mechanisms of ED occurrence are still unclear in patients with CP/CPPS. The aim of the study was to investigate superoxide anion (O-2(center dot-)) and total reactive oxygen species (ROS) production in semen of men with category IIIA CP/CPPS and their association with ED. This prospective study included 33 men with category IIIA CP/CPPS. Control group consisted of 13 healthy men. Total ROS and O-2(center dot-) production were assayed by luminol and lucigenin-dependent chemiluminescence (CL) methods, respectively. ED was evaluated using the IIEF-5 questionnaire. Patients with CP/CPPS had significantly higher seminal total ROS and O-2(center dot-) levels than healthy control subjects (2.9 +/- 0.5 relative light unit (RLU) vs. 2.4 +/- 0.2 RLU, p < 0.001; luminol-dependent CL and 2.5 +/- 0.4 RLU vs. 2.3 +/- 0.2 RLU, p = 0.02; lucigenin-dependent CL, respectively). Seminal O-2(center dot-) and ROS levels were negatively correlated with IIEF-5 scores (r = -0.556, r = -0.536; p < 0.001, respectively). These results may suggest O-2(center dot-)/ROS overproduction could be one of the important mechanisms in the etiology of ED development in CP/CPPS patients.Publication Metadata only Vitamin D receptor gene BsmI, FokI, ApaI, TaqI polymorphisms and bone mineral density in a group of Turkish type 1 diabetic patients(SPRINGER-VERLAG ITALIA SRL, 2011) YAVUZ, DİLEK; Yavuz, Dilek Gogas; Keskin, Lezan; Kiyici, Sinem; Sert, Murat; Yazici, Dilek; Sahin, Ibrahim; Yuksel, Meral; Deyneli, Oguzhan; Aydin, Hasan; Tuncel, Ercan; Akalin, SemaPrevious studies have suggested an influence of vitamin D receptor alleles on bone metabolism and on susceptibility to type 1 diabetes mellitus in different ethnic populations. We aimed to investigate the distribution of vitamin D receptor (VDR) alleles in relation to biochemical bone turnover parameters and bone densitometry measurements in a group of Turkish type 1 diabetic patients. One hundred and seventeen patients (M/F 57/60, 27.6 +/- A 7.3 y duration of diabetes 8.1 +/- A 6.3 y) and 134 healthy controls (M/F 61/73, 26.2 +/- A 5.3 y) were included in the study. Bone mineral density (BMD) was evaluated by dual-energy X-ray absorptiometry (DEXA). The vitamin D receptor gene (VDR) polymorphisms FokI, Bsm1, Apa1, and Taq1 were examined using a PCR-based restriction analysis. Serum levels of calcium, phosphor osteocalcin, intact parathyroid hormone, and C telopeptide were measured. Vitamin D receptor Bsm1 Fok1, Apa1, and Taq1 genotype distributions were not different between patient with diabetes and control groups. BMD was 0.77 +/- A 0.2 g/cm(2) vs. 0.97 +/- A 0.2 g/cm(2) (P = 0.0001) for the femur, 1.0 +/- A 0.1 g/cm(2) vs. 1.13 +/- A 0.1 g/cm(2) (P = 0.001) for type 1 diabetic patients and controls. Bone turnover markers were significantly lower in type 1 diabetic group. BMD measurements and bone metabolic markers were not different between the genotypes in either the patient with diabetes or the controls. The VDR gene polymorphisms, Bsm1, Fok 1, Apa1, and Taq1 showed no influence on bone metabolism in our group of type 1 diabetic patients.Publication Metadata only The antioxidant effects of minocycline and tetracycline on 3-nitropropionic acid induced experimental Huntington's disease model(ELSEVIER SCIENCE INC, 2013) YÜKSEL, MERAL; Yuksel, Meral; Sahin, HulyaPublication Metadata only The effect of carnitine against acrylamide-induced toxicity in rat lung and liver tissues(ELSEVIER IRELAND LTD, 2016) GÜÇLÜ, HÜLYA; Aydemir, S.; Guclu, H.; Ozkan, N.; Yuksel, M.; Erdogan, N.; Omurtag, G. Z.Publication Metadata only The multidisciplinary approach to biochemistry laboratory education(TURKISH BIOCHEM SOC, 2013) HAKLAR, GONCAGÜL; Erkoc, Figen; Sepici-Dincel, Aylin; Kayrin, Levet; Ozkan, Yesim; Eksioglu, Subhan; Yuksel, Meral; Haklar, Goncagul; Yavuz, Ozlem; Celik, Haydar; Konuk, Muhsin; Kurban, Sevil; Uysal, Hamdi; Kisa, Ucler; Bodur, Ebru; Selvi, Meryem; Akca, Gulcin; Simsek, BolkanEuropean Union's Life Long Learning Programmes and the Bologna Process describe new classifications. Related with these new classifications, our higher education system is being restructured under the name of National Qualification Frameworks. Between the National and European programmes comparability and the transparency is expected to promote life-long learning. The workshop named as Biochemistry Laboratory Training Workshop on Multi-Disciplinary Approach was held on 3-4 May 2012 in Ankara with the scope of biochemistry laboratory culture, education, laboratory work and experimental methodology consisted of gain and the development of scientific thinking skills. As a result of the workshop, it was mentioned that, biochemistry theoretical course and biochemistry laboratory are being taught in different faculties, colleges and vocational schools. Biochemistry's interdisciplinary character, its' being closely related to physiology, being based on chemistry/physics principles and conceptions and extending increasingly to molecular biology, molecular genetics and nanoscience have brought new approaches in Biochemistry and Biochemistry Laboratory Education. The need for developing new applications using alternative materials leads to modern experimentation to be employed in teaching biochemistry laboratory at different educational establishments. Taking into account the previous studies, the core laboratory training, achievements and targets identified. The timetable of the teaching-learning and the evaluation process were discussed. Besides the core laboratory programme, the awareness of scientific research projects was discussed. It was also noted the coordination between the different programmes and the basic mandatory structure of the laboratories during the time of adaptation to the European. In addition, difficulties in provision of equipment and supplies, the responsibility of governments, readiness and competencies of students, teaching staff qualifications were discussed for the effective laboratory training. Young scientists and graduate students had actively participated in the workshop. Finally positive steps have been taken to develop the ability to work with the cultures of scientific thinking.Publication Metadata only Better lung protection following death due to rapid exsanguination in rats(BAYCINAR MEDICAL PUBL-BAYCINAR TIBBI YAYINCILIK, 2012) LAÇİN, BERNA; Bostanci, Korkut; Lacin, Berna Karakoyun; Yuksel, Meral; Ercan, Feriha; Yuksel, Mustafa; Batirel, Hasan FevziBackground: This study aims to investigate the effects of death due to rapid exsanguination on the viability of lung tissue. Methods: Fourty-six Sprague-Dawley male rats with a weight range of 310-370 g were included in the study. Rats were divided into six groups: (i) ischemic alone (I group; n=8); (ii) passive exsanguination group of whose major abdominal veins were cut following death (PE group; n=8) (iii) group of whose major abdominal veins were cut and sacrified with rapid exsanguination (RE group; n=8); (iv) lung perfusion group with saline (SP group; n=8); (v) lung perfusion group with Perfadex (PP group; n=8) and (vi) control group (C group; n=6). Rats in all experiement groups except rapid exsanguination ones and all in the control group were euthanized with intrahepatic pentobarbital. Lungs were removed following euthanasia in the controls. In all study groups, lungs were ventilated in the cadavers at room temperature for 120 minutes and kept in warm ischemia. Results: Myeloperoxidase (MPO) activity, luminol chemiluminescence (CL) values and non-viable cell rate were higher in the ischemia group. The PE group had increased MPO activity, lucigenin CL values and nonviable cell rate, whereas the RE group had reduced MPO activity and luminol CL values, compared to ischemia group. MPO activity, lucigenin CL levels and non-viable cell rate were lower in the RE group, compared to PE. The PP had lower MPO activity and luminol CL values, compared to SP or ischemia group, whereas non-viable cell rate increased. Conclusion: Death following rapid exsanguination results in better preservation of lung viability and minimal oxidative injury. This may be explained by rapid loss of platelets and inflammatory cells in the tissue and shift of extravascular fluid to intravascular compartment.