Tug, N. | Sandal, S. | Ozelgun, B. | Yılmaz, B.

Article | 2011 | Gynecological Endocrinology27 ( 1 ) , pp.49 - 54

We have investigated a relationship between DNA damage in sperm and spermiogram profiles in the infertile men. Twenty-one non-smoking infertile men < 40 years of age with no systemic or genetic disease were randomly selected from the pool of infertile couples applied to our clinic. Sperm samples were collected and evaluated according to WHO guidelines. DNA damage of sperm cells was assessed using neutral comet assay. Fifty cells per slide and two slides per sample were scored to evaluate DNA damage. The cells were visually classified into four categories based on DNA migration such as undamaged (UD), little damage (LD), moderate dam . . .age (MD) and significant damage (SD). Total comet scores (TCS) were calculated as: 1 × UD + 2 × LD + 3 × MD + 4 × SD. There was a negative correlation between the percentage of slow- and in situ-motion sperm cells in spermiograms and TCS (p < 0.001 and p < 0.05, respectively). The relationship between the percentage of non-motile sperm cells and TCS was negative (p < 0.001). This study provides new evidence that DNA damage in spermatozoa and sperm motility parameters are negatively correlated. We suggest that evaluation of sperm DNA by the neutral comet assay may be valuable to use in fertility research. © 2011 Informa UK, Ltd Daha fazlası Daha az

Canpolat, S. | Tug, N. | Seyran, A.D. | Kumru, S. | Yılmaz, B.

Article | 2010 | Journal of Physiology and Biochemistry66 ( 1 ) , pp.23 - 28

This study was designed to investigate effects of raloxifene (RLX) and estradiol on bone formation and resorption in intact and ovariectomized (ovx) rat models. In the intact model, a total of 24 adult female rats were divided into three groups: Controls subcutaneously received saline alone. RLX (2 mg/kg) and estradiol (30 µg/kg) were injected to two groups of animals for a period of 6 weeks at two daily intervals. In the second model, rats (n=24) were ovx and allowed to recover for a period of at least 3 weeks. Control group received vehicle alone. Remaining rats were divided into two groups and injected with RLX (2 mg/kg) and estr . . .adiol (30 µg/kg) for 6 weeks. Urine samples were collected from all animals 24 h after the last drug administration. Urinary deoxypyridinoline (DPD) was measured by ELISA. Serum parathyroid hormone (PTH), calcitonin, and osteocalcin levels were measured by immunoradiometric method. Serum concentrations of alkaline phosphatase (ALP), Ca, and inorganic phosphate were determined by enzymatic- colorimetric method. Lumbar vertebrae (L2) of all animals were dissected out and processed for histopathological evaluation. Removal of ovaries significantly elevated urinary DPD levels ( Daha fazlası Daha az

Yıldız, E. | Yılmaz, B. | Dilbaz, S. | Üstün, Y. | Kumru, S.

Article | 2014 | Journal of the Society of Laparoendoscopic Surgeons18 ( 3 ) , pp.23 - 28

Background and Objectives: Postoperative pelvic adhesions are associated with chronic pelvic pain, dyspareunia, and infertility. The aim of this study was to evaluate the adhesion prevention effects of tranexamic acid (TA) and hyaluronate/carboxymethylcellulose (HA/CMC) barrier in the rat uterine horn models on the basis of macroscopic and microscopic adhesion scores and histopathological as well as biochemical parameters of inflammation. Methods: Twenty-one Wistar rats were randomly divided into 3 groups. Ten lesions were created on the antimesenteric surface of both uterine horns by bipolar cautery. Three milliliters of 0.9% sodiu . . .m chloride solution were administered in the control group. A single layer of 2 × 2 cm HA/CMC was plated in group 2. Two milliliters of TA was applied in the last group. All rats were sacrificed at postoperative day 21. Results: No significant difference was found among the control group, the HA/CMC group, and the TA group in terms of macro-adhesion score (P =.206) and microadhesion score (P =.056). No significant difference was found among the 3 groups in terms of inflammation score (P =.815) and inflammatory cell activity (P =.835). Malondialdehyde levels were significantly lower in the control group than in the TA group and HA/CMC group (P =.028). Superoxide dismutase and glutathione S-transferase activities were found to be higher in the control group than in the TA group (P =.005) and HA/CMC group (P =.009). Conclusions: TA and HA/CMC had no efficacy in preventing macroscopic or microscopic adhesion formation and decreasing inflammatory cell activity or inflammation score in our rat models. TA and HA/CMC increased the levels of free radicals and reduced the activities of superoxide dismutase and glutathione S-transferase enzymes, which act to reduce tissue injury. © 2014 by JSLS, Journal of the Society of Laparoendoscopic Surgeons. Published by the Society of Laparoendoscopic Surgeons, Inc Daha fazlası Daha az

Ozcan, M. | Alcin, E. | Ayar, A. | Yılmaz, B. | Sandal, S. | Kelestimur, H.

Article | 2011 | Neuroscience Letters492 ( 1 ) , pp.55 - 58

Kisspeptins, which are alternatively called as metastin since they were originally identified as products of metastasis suppressor gene KiSS-1, are the natural ligands for the G protein-coupled receptor 54 (GPR54). Kisspeptins are the most potent activators of hypothalamic-pituitary-gonadal (HPG) axis reported to date. The pulsatile pattern of GnRH release, which results in the intermittent release of gonadotropic hormones from the pituitary, has a critical importance for reproductive function but the factors responsible from this release pattern are not known. Therefore, the pattern of kisspeptin-induced intracellular signaling and . . . the role of PKC in the intracellular signaling cascade were investigated by fluorescence calcium imaging using the immortalized GnRH-secreting GT1-7 hypothalamic neurons. Kisspeptin-10 caused a triphasic change characterized by an initial small increase followed by a significant decrease and increase in intracellular free calcium concentrations ([Ca 2+] i). The changes in [Ca 2+] i were significantly attenuated by pre-treatment with protein kinase C inhibitor. The compatibility of appeared mirrored-patterns of kisspeptin-10-induced changes in [Ca 2+] i concentrations in these neurons and GnRH secretion confirm the importance of intracellular calcium flux downstream from GPR54 through PKC signaling pathway. © 2011 Elsevier Ireland Ltd Daha fazlası Daha az

Sandal, S. | Tuneva, J. | Yılmaz, B. | Carpenter, D.O.

Article | 2009 | Cell Biochemistry and Function27 ( 3 ) , pp.155 - 161

We investigated the effects of lipids on thymocyte function. The effects of application of cholesterol or docosahexaenoic acid (DHA), a C22, omega-3 (n-3) polyunsaturated fatty acid (PUFA), on viability and intracellular calcium concentrations of acutely isolated mouse thymocytes were investigated using flow cytometry. Cholesterol (100 µM) caused significant cell death after 30-60 min whether or not calcium was present in the medium. Cell death was associated with an elevation of intracellular calcium whether or not calcium was present in the extracellular medium. However, the elevation of calcium concentration was not responsible f . . .or the cell death since calcium levels in the presence of ionomycin rose higher without significant cell death. DHA had similar actions but was more potent, causing significant cell death and elevation of calcium concentration within 5 min at 1 µM. In the absence of extracellular calcium 1 µM DHA caused 100% cell death within 15 min. Linolenic acid, a C18 omega-3 fatty acid also caused cytotoxicity at low concentrations whether or not albumin was present, but omega-6 or saturated C22 fatty acids were much less effective. These observations demonstrate that thymocyte viability is very sensitive to acute exposure to low concentrations of omega-3 fatty acids. Copyright © 2009 John Wiley & Sons, Ltd Daha fazlası Daha az

Tekin, S. | Erden, Y. | Sandal, S. | Etem Onalan, E. | Ozyalin, F. | Ozen, H. | Yılmaz, B.

Article | 2017 | Archives of Physiology and Biochemistry123 ( 1 ) , pp.9 - 15

Apelin is an adipose tissue derived peptidergic hormone. In this study, 40 male Sprague–Dawley rats were used (four groups; n = 10). Apelin-13 at three different dosages (1, 5 and 50 µg/kg) was given intraperitoneally while the control group received vehicle the same route for a period of 14 days. In results, apelin-13 caused significant decreases in serum testosterone, luteinizing hormone and follicle-stimulating hormone levels (p < 0.05). Administration of apelin-13 significantly increased body weights, food intake, serum low-density lipoprotein and total cholesterol levels (p < 0.05), but caused significant decreases in high-dens . . .ity lipoprotein levels (p < 0.05). Serum glucose and triglyceride levels were not significantly altered by apelin-13 administration. Significant decreases in both uncoupling protein (UCP)-1 levels in the white and brown adipose tissues and UCP-3 levels in the biceps muscle (p < 0.05) were noted. The findings of the study suggest that apelin-13 may not only lead to obesity by increasing body weight but also cause infertility by suppressing reproductive hormones. © 2016 Informa UK Limited, trading as Taylor & Francis Group Daha fazlası Daha az

Çlatak, J. | Özilgen, M. | Olcay, A.B. | Yılmaz, B.

Article | 2018 | International Journal of Exergy25 ( 1 ) , pp.1 - 33

Thermodynamic aspects of skeletal and cardiac muscle work performance are assessed with the data obtained from the literature. Since the second law muscle work efficiency decreases with declining metabolic energy conversion efficiency in the mitochondria, followed by structural failure of the muscles during ageing, the thermodynamic aspects of the muscle work ageing process were simulated by incorporating the decreasing second law muscle work efficiency with the exercise data obtained with the healthy young adults. Within limits of the data analysed here, glucose utilisation ability of the cardiac muscle appears to be the most criti . . .cal factor determining its work performance. The left and the right ventricles of the enlarged heart had the ability of utilising approximately 3.5 and 2.7 times less glucose, respectively, than their healthy counterparts. The work performance and the entropy generation by the enlarged and the healthy hearts maintained the same ratios. Copyright © 2018 Inderscience Enterprises Ltd Daha fazlası Daha az

Yalçınkaya, B.H. | Yılmaz, B. | Özilgen, M.

Article | 2019 | International Journal of Global Warming19 ( 3 ) , pp.233 - 250

Thermodynamic analyses are performed to determine the effects of global warming on information transmittance in the squid giant axon. Squids are cold-blooded animals and their body temperature is the same as that of the environment. Modelling showed that at 6.3°C energy cost, exergy destruction and entropy generation were 1.77 × 10–10 kJ/cm2, 3.49 × 10–9 kJ/cm2, and 1.25 × 10–11 kJ/K cm2, respectively. Entropy generation decreased with temperature increase, implying that living became easier for the squid. Thermodynamic analyses performed in this study may help to explain why the squid populations thrive with global warming. Copyrig . . .ht © 2019 Inderscience Enterprises Ltd Daha fazlası Daha az

Yılmaz, B.

Article | 2012 | Turkish Journal of Immunology18 ( 2 ) , pp.233 - 250

[No abstract available]

Ozcelik, O. | Algul, S. | Yılmaz, B.

Article | 2018 | Cellular and molecular biology (Noisy-le-Grand, France)64 ( 10 ) , pp.130 - 133

This study aimed to investigate the potential effects of acute soccer matches performed in morning, afternoon and at night on both nesfatin-1 and irisin levels in trained subjects. Total of 20 male subjects performed in soccer matches at three different times of day: morning, afternoon, and night. Pre- and post-match venous blood samples were taken, and levels of both nesfatin-1 and irisin were analysed using the enzyme-linked immunosorbent assay (ELISA). Following all matches, the subjects' irisin levels increased significantly in all subjects (p < 0.0001). Nesfatin-1 levels were also increased after the matches; however, the in . . .crease was statistically significant for morning (P=0.01) and night-time (p=0.009). The subjects' nesfatin-1 levels did not increase in all subjects and decrease of nesfatin-1 levels observed in some subjects after matches. This study finds that soccer matches performed different workout times have strong stimulatory effects on irisin levels in all subjects but nesfatin-1 response varied among the subjects and it did not change significantly in afternoon match Daha fazlası Daha az

Uslu, U. | Sandal, S. | Cumbul, A. | Yildiz, S. | Aydin, M. | Yılmaz, B.

Article | 2013 | Human and Experimental Toxicology32 ( 5 ) , pp.476 - 482

In this study, we investigated the effects of polychlorinated biphenyls (PCBs) and organochlorinated pesticides on the serum levels of luteinising hormone (LH), follicle stimulating hormone (FSH) and weights and histomorphometry of uterine tissue in immature female rats using uterotrophic assay. A total of 36 rats were randomly divided into six groups (n = 6 per group) as control, oestradiol (E2, 100 µg/kg), PCB 180, Aroclor 1221, endosulfan and mirex at 10 mg/kg dosage. After 3 days of injections (subcutaneous), animals were decapitated and blood samples were collected. Uteri were dissected, weighed out and then fixed in 10% formal . . .dehyde. They were processed for histomorphometry. The serum levels of LH and FSH were determined by enzyme immunoassay.Uterine weight was significantly increased by E 2 and reduced by mirex (p < 0.001 and p < 0.05, respectively). Total volume of uterus was significantly raised by E2, Aroclor 1221 and endosulfan compared with that of the control group (p < 0.01). The ratio of epithelium was significantly increased by E2, PCBs and pesticides (p < 0.01). The uterine cavity ratio was decreased by aroclor (p < 0.01), PCB 180 and mirex (p < 0.05). The serum levels of LH did not significantly differ among the groups but the levels of FSH were decreased by PCB 180 and endosulfan (p < 0.05 and p < 0.01, respectively). These findings suggest that PCB 180, Aroclor 1221 and endosulfan may be estrogenic in immature uterotrophic assay. © 2013 The Author(s) Daha fazlası Daha az

Alcin, E. | Özcan, M. | Ayar, A. | Yılmaz, B. | Türköz, Y. | Keleştimur, H.

Article | 2011 | Turkiye Klinikleri Journal of Medical Sciences31 ( 6 ) , pp.1477 - 1483

Objective: The aim of this study was to investigate the effects of exogenous kisspeptin on pubertal maturation in immature female rats. Material and Methods: Wistar female rats were weaned when they were 21 days old. The rats were divided into two groups. Controls (n=10) received saline only (1 ml/kg). Experimental rats (n=9) were intraperitoneally injected with daily 100 nmol kisspeptin-10 between 09.00h-10.00h a.m. starting from the day 26. Body weight and food intake were daily determined, and vaginal opening (VO) was daily monitored starting from day 26. The animals were decapitated when the first diestrus was determined by vagi . . .nal smears. Upon decapitation, serum was separated and stored at -20°C until measurement of leptin, luteinizing hormone (LH) and estradiol. Uterus and ovaries were dissected out and weighed. Results: Intrape-ritoneal injection of 100 nmol kisspeptin-10 did not change median VO ages. There were no differences in food intake, and percentages of body weight change, between control and kisspeptin groups during the experimental period. Kisspeptin administration elicited significant ( Daha fazlası Daha az