Yılmaz, B. | Sandal, S.

Article | 2012 | Turkish Journal of Immunology18 ( 2 )

[No abstract available]

Semerciöz, A.S. | Yılmaz, B. | Özilgen, M.

Article | 2018 | International Journal of Exergy26 ( 3 ) , pp.359 - 391

Entropy generation behaviour of the rats is affected by their diet and nature of being lean or obese. Thermodynamic analyses showed that the obese Zucker rats may generate 22,092 kJ/K of life span entropy when fed soybean oil diet and 38,718 kJ/K of entropy when fed with butter fat. Their lean counterparts may generate 15,314 kJ/K of life span entropy when fed with soybean oil diet and 47,657 kJ/K of entropy and when fed with butter fat diet. The lean Zucker rats fed with butter fat diet had 92%, while the obese Zucker rats fed with soybean oil diet had 72%, wasted life-time work potential. Obese Zucker rats fed with butter fat diet . . . performed approximately 48% more total physical work and generated 48% more muscular heat through their life span than the lean rats fed with soybean oil diet. Copyright © 2018 Inderscience Enterprises Ltd Daha fazlası Daha az

Yılmaz, B.

Article | 2012 | Turkish Journal of Immunology18 ( 2 ) , pp.359 - 391

[No abstract available]

Yeşil, Ç. | Yılmaz, B. | Korkmaz, E.E.

Conference Object | 2011 | Proceedings of the 2011 11th International Conference on Hybrid Intelligent Systems, HIS 2011 , pp.468 - 473

Hybridization of local search algorithms yield promising algorithms for combinatorial optimization problems such as Graph Coloring Problem (GCP). This paper presents a new meta-heuristic Simulated Annealing with Backtracking (SABT) and shows the effect of hill climber and tabu search on SABT for solving GCP. The algorithm proposed merges the power of simulated annealing approach and backtracking mechanism. Some hill climbers are integrated for fine tuning and also tabu search is integrated for avoiding from redundant search. Several tests are run on a collection of benchmarks from DIMACS challenge suite and promising results are obt . . .ained. A comparison of SABT framework with some other state-of-the-art algorithms is presented along with an analysis of the performance of the algorithm. © 2011 IEEE Daha fazlası Daha az

Browne, E.P. | Dinc, S.E. | Punska, E.C. | Agus, S. | Vitrinel, A. | Erdag, G.C. | Yılmaz, B.

Article | 2014 | Journal of Human Lactation30 ( 4 ) , pp.450 - 457

Background: Breast cancer is the most frequently diagnosed cancer among Turkish women and both the incidence and associated mortality appear to be increasing. Of particular concern is the percentage of young women diagnosed with breast cancer; roughly 20% of all breast cancer diagnoses in Turkey are in women younger than 40 years. Increased DNA methylation in the promoter region of tumor suppressor genes is a promising molecular biomarker, and human milk provides exfoliated breast epithelial cells appropriate for DNA methylation analyses. Comparisons between DNA methylation patterns in epithelial (epithelial-enriched) and nonepithel . . .ial (epithelial-depleted) cell fractions from breast milk have not been reported previously.Objective: In the present study, we examined promoter methylation of 3 tumor suppressor genes in epithelial-enriched and epithelial-depleted cell fractions isolated from breast milk of 43 Turkish women.Methods: Percentage methylation in the promoter region of Rass association domain family 1 (RASSF1), secreted frizzle related protein 1 (SFRP1), and glutathione-S-transferase class pi 1 was determined by pyrosequencing of the epithelialenriched and epithelial-depleted cell fractions.Results: Pyrosequencing identified a few subjects with significantly increased methylation in 1 or more genes. There was little correlation between the 2 cell fractions within individuals; only 1 woman had increased methylation for 1 gene (SFRP1) in both her enriched and depleted cell fractions. Methylation was positively associated with age for SFRP1 (epithelial-depleted fraction) and with body mass index for RASSF1 (epithelial-enriched cell fraction), respectively.Conclusion: Overall, results show that the methylation signals vary between different cell types in breast milk and suggest that breast milk can be used to assess DNA methylation patterns associated with increased breast cancer risk. © The Author(s) 2014 Daha fazlası Daha az

Tug, N. | Ayvaci Tasan, H. | Sargin, M.A. | Dogan Taymur, B. | Ayar, A. | Kilic, E. | Yılmaz, B.

Article | 2017 | European Review for Medical and Pharmacological Sciences21 ( 2 ) , pp.5028 - 5033

OBJECTIVE: Erythropoietin (EPO) is a glycoprotein hormone that regulates erythropoiesis. EPO activity has also been detected in a variety of tissue including the nervous system, and female and male reproductive organs. It has been shown that EPO causes relaxation in vascular smooth muscle. In the present study, we have investigated effects of EPO on spontaneous and oxytocin-induced contractions of non-pregnant rat myometrium. MATERIALS AND METHODS: Myometrial stripes were obtained from adult Wistar rats at the oestrous stage. The samples were placed in an isolated organ chamber under physiological conditions and 1 g passive tension. . . . Epoetin beta (rEPO) was added cumulatively at 0.1, 1 and 10 IU/ml concentrations to the myometrial samples showing regular spontaneous contractions for periods of 30 min. Frequency and amplitude of contractions were electrophysiologically recorded and analyzed by using a BIOPAC data acquisition system. RESULTS: rEPO inhibited both area under curve and frequency of spontaneous contractions (ANOVA, n1, 2 = 9, f1 = 20.938, f2 = 20.492, p1,2 = 0.000). The inhibitory effect was insignificant at 0.1 mIU/ml rEPO level (Tukey HSD, p1 = 0.051, p2 = 0.581). In the oxytocin treated myometrial samples, a single dose of 1 IU/ml rEPO was studied. The area under curve and frequency values of these samples were inhibited by rEPO (Student's t-test, n = 9, t1 = 4.776, p1 = 0.000; t2 = 2.835, p2 = 0.012, respectively). CONCLUSIONS: rEPO inhibited spontaneous and oxytocin-induced rat myometrial contractions at 1 and 10 IU/ml concentrations. It appeared that the effect was dose-dependent. © 2017 Verduci Editore s.r.l. All rights reserved 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

Yılmaz, B. | Korkmaz, E.E.

Conference Object | 2010 | Proceedings of the 2010 10th International Conference on Intelligent Systems Design and Applications, ISDA'10 , pp.1171 - 1176

Linear Linkage Encoding (LLE) is a powerful encoding scheme utilized when genetic algorithms (GAs) are applied to grouping problems. It discards the redundancy of other traditional encoding schemes. However, some genetic operators are quite costly in terms of computational time when LLE is utilized. In this study, two supplementary encoding schemes Linear Linkage Encoding with Ending Node Links (LLE-e) and Linear Linkage Encoding with Backward Links (LLE-b) are designed and used together with LLE. When a genetic operator is costly in LLE, the operation is carried out on one of the supplementary encodings and the result is reflected . . .back to LLE. The algorithm is implemented in a Multi Objective Genetic Algorithm (MOGA) framework and various tests are carried out on Graph coloring Problem (GCP) instances obtained from DIMACS Challenge Suite. A performance improvement has been obtained when both supplementary encoding schemes are included in the algorithm. © 2010 IEEE 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

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

Article | 2008 | Mutation Research - Genetic Toxicology and Environmental Mutagenesis654 ( 1 ) , pp.88 - 92

Polychlorinated biphenyls (PCBs) are known to be carcinogenic, but the mechanisms of this action are uncertain. Most, but not all, studies have concluded that PCBs are not directly mutagenic, and that much if not all of the carcinogenic activity resides in the fraction of the PCB mixture that contains congeners with dioxin-like activity. The present study was designed to determine genotoxic effects of an ortho-substituted, non-coplanar congener, 2,2',5,5'-tetrachlorobiphenyl (PCB 52), and a non-ortho-substituted coplanar congener with dioxin-like activity, 3,3',4,4'-tetrachlorobiphenyl (PCB 77) on cultured human peripheral lymphocyt . . .es. DNA damage was assessed by use of the comet assay (alkaline single-cell gel electrophoresis). After cell cultures were prepared, test groups were treated with different concentrations of PCB 52 (0.2 and 1 µM) and PCB 77 (1 and 10 µM) for 1 h at 37 °C in a humidified carbon dioxide incubator, and compared to a DMSO vehicle control group. The cells were visually classified into four categories on the basis of extent of migration such as undamaged (UD), low damage (LD), moderate damage (MD) and high damage (HD). The highest concentration of PCBs 52 and 77 significantly increased DNA breakage in human lymphocytes (p < 0.001). Our results indicate that both the non-coplanar PCB 52 and coplanar PCB 77 cause DNA damage, and that the ortho-substituted congener was significantly more potent than the dioxin-like coplanar congener. © 2008 Elsevier B.V. All rights reserved 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

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