Yazar "Ulukaya, Engin" seçeneğine göre listele

Listeleniyor 1 - 4 / 4
  • [ X ]
    Öğe
    Can safe and long-term exposure to extremely low frequency (50 Hz) magnetic fi elds aff ect apoptosis, reproduction, and oxidative stress?
    (Taylor & Francis Ltd, 2013) Akdag, Mehmet Zulkuf; Dasdag, Suleyman; Uzunlar, Ali Kemal; Ulukaya, Engin; Oral, Arzu Yilmaztepe; Celik, Necla; Aksen, Feyzan
    Purpose : To determine whether 50 Hz extremely low frequency-magnetic fi elds (ELF-MF) aff ects apoptotic processes, oxidative damage, and reproductive characteristics such as sperm count and morphology in rat testes. Materials and methods : Thirty male Sprague-Dawley rats were used in the present study, which were divided into three groups (sham group, n = 10, and two experimental groups, n = 10 for each group). Rats in the experimental group were exposed to 100 and 500 mu T ELF-MF (2 h/day, 7 days/week, for 10 months) corresponding to exposure levels that are considered safe for humans. The same experimental procedures were applied to the sham group, but the ELF generator was turned off. Tissues from the testes were immunohistochemically stained for active (cleaved) caspase-3 in order to measure the apoptotic index by a semi-quantitative scoring system. The levels of catalase (CAT), malondialdehyde (MDA), myeloperoxidase (MPO), total antioxidative capacity (TAC), total oxidant status (TOS), and oxidative stress index (OSI) were also measured. Additionally, epididymal sperm count and sperm morphology was evaluated. Results : There were no signifi cant diff erences in the reproductive and oxidative stress parameters between the sham group and the exposed groups (p > 0.05). While no diff erence was observed between the fi nal apoptosis score of the sham and the 100 mu T ELF-MF group (p > 0.05), the fi nal apoptosis score was higher in the 500 mu T ELF-MF exposure group than in the sham group (p < 0.05). Conclusion : Long-term exposure to 100 mu T and 500 mu T ELF-MF did not aff ect oxidative or antioxidative processes, lipid peroxidation, or reproductive components such as sperm count and morphology in testes tissue of rats. However, long-term exposure to 500 mu T ELF-MF did aff ect active-caspase-3 activity, which is a well-known apoptotic indicator.
  • [ X ]
    Öğe
    Effect of Mobile Phone Exposure on Apoptotic Glial Cells and Status of Oxidative Stress in Rat Brain
    (Taylor & Francis Inc, 2009) Dasdag, Suleyman; Akdag, M. Zulkuf; Ulukaya, Engin; Uzunlar, Ali Kemal; Ocak, Ali Riza
    The aim of this study was to investigate the effects of mobile phone exposure on glial cells in brain. The study carried out on 31 Wistar Albino adult male rats. The rat heads in a carousel exposed to 900MHz microwave. For the study group (n:14), rats exposed to the radiation 2 h per day (7 days in a week) for 10 months. For the sham group (n: 7), rats were placed into the carousel and the same procedure was applied except that the generator was turned off. For the cage control (n: 10), nothing applied to rats in this group. In this study, rats were euthanized after 10 months of exposure periods and brains were removed. Brain tissues were immunohistochemically stained for the active (cleaved) caspase-3, which is a well-known apoptosis marker, and p53. The expression of the proteins was evaluated by a semi-quantitative scoring system. However, total antioxidative capacity (TAC), catalase, total oxidant status (TOS), and oxidative stress index were measured in rat brain. Final score for apoptosis in the exposed group was significantly lower than the sham (p < 0.001) and the cage control groups (p < 0.01). p53 was not significantly changed by the exposure (p > 0.05). The total antioxidant capacity and catalase in the experimental group was found higher than that in the sham group (p < 0.001, p < 0.05). In terms of the TOS and oxidative stress index, there was no statistically significant difference between exposure and sham groups (p > 0.05). In conclusion, the final score for apoptosis, total antioxidant capacity and catalase in rat brain might be altered by 900MHz radiation produced by a generator to represent exposure of global systems for mobile communication (GSM) cellular phones.
  • [ X ]
    Öğe
    Effects of Extremely Low-Frequency Magnetic Field on Caspase Activities and Oxidative Stress Values in Rat Brain
    (Humana Press Inc, 2010) Akdag, Mehmet Zulkuf; Dasdag, Suleyman; Ulukaya, Engin; Uzunlar, Ali Kemal; Kurt, Mustafa Ayberk; Taskin, Abdullah
    This study was aimed to investigate the effect of extremely low-frequency magnetic field (ELF-MF) on apoptosis and oxidative stress values in the brain of rat. Rats were exposed to 100 and 500 mu T ELF-MF, which are the safety standards of public and occupational exposure for 2 h/day for 10 months. Brain tissues were immunohistochemically stained for the active (cleaved) caspase-3 in order to measure the apoptotic index by a semi-quantitative scoring system. In addition, the levels of catalase (CAT), malondialdehyde (MDA), myeloperoxidase (MPO), total antioxidative capacity (TAC), total oxidant status (TOS), and oxidative stress index (OS!) were measured in rat brain. Final score of apoptosis and MPO activity were not significantly different between the groups. CAT activity decreased in both exposure groups (p<0.05), while TAC was found to be lower in ELF 500 group than those in ELF-100 and sham groups (p<0.05). MDA, TOS, and OSI values were found to be higher in ELF-500 group than those in ELF-100 and sham groups (p<0.05). In conclusion, apoptosis was not changed by long-term ELF-MF exposure, while both 100 and 500 mu T ELF-MF exposure induced toxic effect in the rat brain by increasing oxidative stress and diminishing antioxidant defense system.
  • [ X ]
    Öğe
    Mobile phone exposure does not induce apoptosis on spermatogenesis in rats
    (Elsevier Science Inc, 2008) Dasdag, Suleyman; Akdag, M. Zulkuf; Ulukaya, Engin; Uzunlar, Ali Kemal; Yegin, Dilek
    Background. Some studies have reported that microwave radiation can have adverse effects on reproduction. Therefore, the purpose of this study was to investigate the apoptosis-inducing effect of mobile phone exposure on spermatogonia in seminiferous tubules. Methods. The study was carried out on 31 Wistar albino adult male rats. The rats were separated into three groups in this study (cage control: 10, sham group: 7, and exposed group: 14). For the study group, rats were exposed to radiation 2 h/day (7 days/week) for 10 months. For the sham group, rats were placed into the carousel and the same procedure was applied except that the generator was turned off. For the cage control, nothing was applied to the rats in this group and they completed their life cycle in the cage during the study period. In this study, rats were sacrificed after 10 months of exposure and their testes were taken. Testes tissue was immunohistochemically stained for the active (cleaved) caspase-3. Positively stained cells were counted in up to ten different areas, and the frequency of positive cells was determined in percentage. Scoring was done by taking into account both the intensity of staining and the distribution of positively stained cells. Therefore, protein expression was evaluated by a serniquantitative scoring system. Results. The final score for apoptosis of testes in the exposed group was not statistically significant according to the sham and the cage control groups (p >0.05). Conclusions. The results of this study showed that 2 h/day (7 days/week) exposure of 900 MHz radiation over a period of 10 months does not affect the active (cleaved) caspase-3 levels in testes, a well-known feature of typical apoptosis. (C) 2008 IMSS. Published by Elsevier Inc.