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Öğe Amino Acids of Seminal Plasma Associated With Freezability of Bull Sperm(Frontiers Media S.A., 2020) Ugur M.R.; Dinh T.; Hitit M.; Kaya A.; Topper E.; Didion B.; Memili E.Sperm cryopreservation is an important technique for fertility management, but post-thaw viability of sperm differs among breeding bulls. With metabolites being the end products of various metabolic pathways, the contributions of seminal plasma metabolites to sperm cryopreservation are still unknown. These gaps in the knowledge base are concerning because they prevent advances in the fundamental science of cryobiology and improvement of bull fertility. The objective of this study was to test the hypothesis that seminal plasma amino acids are associated with freezability of bull sperm. To accomplish this objective, amino acid concentrations in seminal plasma from seven bulls of good freezability (GF) and six bulls of poor freezability (PF) were quantified using gas chromatography–mass spectrometry (GC–MS). Multivariate and univariate analyses were performed to identify potential freezability biomarkers. Pathways and networks analyses of identified amino acids were performed using bioinformatic tools. By analyzing and interpreting the results we demonstrated that glutamic acid was the most abundant amino acid in bull seminal plasma with average concentration of 3,366 ± 547.3 nM, which accounts for about 53% of total amino acids. The other most predominant amino acids were alanine, glycine, and aspartic acid with the mean concentrations of 1,053 ± 187.9, 429.8 ± 57.94, and 427 ± 101.3 nM. Pearson’s correlation analysis suggested that phenylalanine concentration was significantly associated with post-thaw viability (r = 0.57, P-value = 0.043). Significant correlations were also found among other amino acids. In addition, partial least squares-discriminant analysis (PLS-DA) bi-plot indicated a distinct separation between GF and PF groups. Phenylalanine had the highest VIP score and was more abundant in the GF groups than in the PF groups. Moreover, pathway and network analysis indicated that phenylalanine contributes to oxidoreductase and antioxidant reactions. Although univariate analysis did not yield significant differences in amino acid concentration between the two groups, these findings are significant that they indicate the potentially important roles of amino acids in seminal plasma, thereby building a foundation for the fundamental science of cryobiology and reproductive biotechnology. © Copyright © 2020 Ugur, Dinh, Hitit, Kaya, Topper, Didion and Memili.Öğe ANCA positive propylthiouracil induced pyoderma gangrenosum [2](Editrice Kurtis s.r.l., 2006) Gungor K.; Gonen S.; Kisakol G.; Dikbas O.; Kaya A.[Abstract not Available]Öğe Applications of Metabolomics in Reproductive Biology(wiley, 2017) Cazaux Velho A.L.; Oliveira R.; Dinh T.; Moura A.; Kaya A.; Memili E.Metabolomics can be performed associated with other omics approaches such as genomics, transcriptomics, and proteomics. For example, a recent study showed interesting results using an Integrative Personal Omics Profile (iPOP) to identify markers for possible diseases affecting an individual. This chapter suggests that such a method leads to an early diagnosis and facilitates prevention of certain diseases, such as type 2 diabetes, aplastic anemia, human rhinovirus infection, and respiratory syncytial virus infection. For assisted reproductive technologies (ART), metabolomics methods have been chosen as noninvasive approaches to improve the assessment of embryo quality. Metabolic profiling analysis of follicular fluids (FF) from lactating cows and heifers by gas chromatography-mass spectrometry (GC-MS) identified the presence of greater concentrations of saturated fatty acids in follicles from cows than those from heifers. Large animals have been used as models for research of human disease and physiology due to their specific physiological characteristics, sometimes similar to the human. © 2017 by John Wiley & Sons, Inc. All rights reserved.Öğe Dual ectopic thyroid(Elsevier BV, 2003) Emlik D.; Karabacako?lu A.; Karaköse S.; Kaya A.; Taştekin G.Ectopic thyroid tissue can be found anywhere from foramen cecum and the normal cervical position of the thyroid gland. It occurs most commonly at the base of tongue, known as lingual, followed by sublingual and the anterior midline of neck. We present the patient with dual ectopic thyroid, one of them is at the base of tongue and the other is in the left submandibular region. The purpose of this report is to demonstrate the findings of ultrasonography, computed tomography, magnetic resonance imaging and scintigraphy and to emphasize the importance of performing a thyroid scan in every case of thyroid ectopia to accurately identify all sites of functioning thyroid tissue. © 2003 Elsevier Ireland Ltd. All rights reserved.Öğe The effect of Sildenafil (Viagra®) on serving capacity of rams [Der einfluss von Sildenafil (Viagra®) auf das geschlechtsverhalten von schafböcken](2005) Çoyan K.; Kaya A.Introduction: The aim of this study was to investigate the effect of sildenafil administration on mating performance in the rams. Material and methods: In a preliminary experiment, serving capacity of 21 Konya Merino rams was determined by pen mating test performed individually 3 times with 4 estrus ewes during a period of 1 hour. Based on the average number of mating in the preliminary experiment, 8 rams which had served 5 or less than 5 times were considered to be of low serving capacity. The other 8 rams which had served 7 and more than 7 times in an hour were considered to be of high serving capacity. In total 16 rams were selected for the further experiment. The other 5 rams which had served 6 times in the pen mating test were not considered for the further experiment. 1 hour before serving capacity evaluation, 4 rams from each group were treated intrarectally with 100 mg Sildenafil (Viagra®) homogenized in cocoa oil. The remaining rams from each group were treated only with cocoa oil and used as control. In addition to the total number of mating in an hour, rams were evaluated for the reaction time which is the time period between introduction and first mating. Results: Sildenafil administration resulted in an increase in the total serving capacity of rams in both groups. The reaction time did not differ significantly. Conclusion: Mating performance in rams is positively influenced by Sildenafil. Further investigations are necessary to determine whether decreased libido could successfully be treated with this drug.Öğe Increased prolactin levels after administration of beta adrenergic receptor blockers(1991) Karabulut L.; Kaya A.; Polat M.We investigated the effect of acebutalol on PRL secretion which was beta adrenergic receptor blocker. Acebutalol was applied with diazepam to the first group and only acebutalol was applied to the second groups. The increase in prolactin levels have been recorded in both groups.Öğe The relation of HOMA index with endothelial functions determined by flow mediated dilatation method among hyperglycemic patients(2007) Karaba? T.; Kaya A.; Yavuz S.; Kaya C.; Koc F.; Yeter E.Aims/Objective: To research the relation between "homeostasis model assessment of insulin resistance index (HOMA-IR)" and endothelial functions, determined by the flow mediated dilatation (FMD) method with brachial artery ultrasound and the atherosclerotic factors influencing these values among hyperglycemic patients taking the same type of oral antidiabethics (sulphonylurea). Method: Seventy type-2 diabetes mellitus patients (33 males and 37 females, mean age 53.5 ± 8.5 years) who took the same oral antidiabetic drugs, and 40 people (22 males, 18 females, mean age 46.9 ± 14.6 years) as control group who had no hypertension and no cardiovascular disease were included in the study. The HOMA-IR of the patients was calculated. Patients who had HOMA-IR ? 3.6 were assumed as insulin resistance (IR) existing and who had HOMA-IR < 3.6 were not existing. The groups were divided into the IR existing (group 1) and IR not existing (group 2). Endothelium dependent dilatation (FMD) values of the groups and the controls were calculated as percentage increase as to basic values in reactive hyperemia phase. Results: FMD percentages among group 1 were significantly lower than the control group (p < 0.05). No difference was observed between group 2 and the control group (p > 0.05). Percentage increase between the basic level and reactive hyperemy phase was not found statistically significant (p > 0.05) between group 1 and 2. While the main factors influencing FMD percantages were total cholesterol, triglyceride, high-density lipoprotein, and low-density lipoprotein levels for group 1. No parameter could be found affecting the related percentages for group 2. Conclusion: While endothelial functions, determined by FMD method, were impaired with hyperglycemic patients whose HOMA-IR was ? 3.6; it was normal among hyperglycemics whose HOMA-IR was < 3.6.Öğe Sperm Chromatin Dynamics Associated with Male Fertility in Mammals(wiley, 2017) Kutchy N.A.; Dogan S.; Kaya A.; Moura A.; Memili E.Instead of two protamines (PRM1 and PRM2) as in human and mouse sperms, presence of only PRM1 in bull sperm raises an interesting question about the mechanism(s) regulating sperm chromatin structure. During spermatogenesis, spermatozoa that are present in syncytium share mRNA and proteins through cytoplasmic bridges and are phenotypically diploid. Chromatin remodeling occurs during spermatogenesis where linker histones are gradually replaced by testis-specific variants, followed by the replacement of histones with transition proteins and then with protamines. Increased percentage of histone retention is expected to cause infertility in males. Although protamines are involved in sperm chromatin condensation and function, there is restrictive positive selection on only a few functional sites. Improper packaging of sperm DNA caused partly by reduced protamination predisposes sperm DNA to damage, which then interferes with fertilization and early embryonic development. Abnormal chromatin condensation in sperm during spermatogenesis and abnormal chromatin decondensation during pronucleus formation (postfertilization) can result in reproductive problems. © 2017 by John Wiley & Sons, Inc. All rights reserved.Öğe Sperm protamine-status correlates to the fertility of breeding bulls(Society for the Study of Reproduction, 2015) Dogan S.; Vargovic P.; Oliveira R.; Belser L.E.; Kaya A.; Moura A.; Sutovsky P.During fertilization, spermatozoa make essential contributions to embryo development by providing oocyte activating factors, centrosomal components, and paternal chromosomes. Protamines are essential for proper packaging of sperm DNA; however, in contrast to the studies of oocyte-related female infertility, the influence of sperm chromatin structure on male infertility has not been evaluated extensively. The objective of this study was to determine the sperm chromatin content of bull spermatozoa by evaluating DNA fragmentation, chromatin maturity/protamination, PRM1 protein status, and nuclear shape in spermatozoa from bulls with different fertility. Relationships between protamine 1 (PRM1) and the chromatin integrity were ascertained in spermatozoa from Holstein bulls with varied (high vs. low) but acceptable fertility. Sperm DNA fragmentation and chromatin maturity (protamination) were tested using Halomax assay and toluidine blue staining, respectively. The PRM1 content was assayed using Western blotting and in-gel densitometry, flow cytometry, and immunocytochemistry. Fragmentation of DNA was increased and chromatin maturity significantly reduced in spermatozoa from low-fertility bulls compared to those from high-fertility bulls. Field fertility scores of the bulls were negatively correlated with the percentage of spermatozoa displaying reduced protamination and fragmented DNA using toluidine blue and Halomax, respectively. Bull fertility was also positively correlated with PRM1 content by Western blotting and flow cytometry. However, detection of PRM1 content by Western blotting alone was not predictive of bull fertility. In immunocytochemistry, abnormal spermatozoa showed either a lack of PRM1 or scattered localization in the apical/acrosomal region of the nuclei. The nuclear shape was distorted in spermatozoa from low-fertility bulls. In conclusion, we showed that inadequate amount and localization of PRM1 were associated with defects in sperm chromatin structure, coinciding with reduced fertility in bulls. These findings are highly significant because they reveal molecular and morphological phenotypes of mammalian spermatozoa that influence fertility. © 2015 by the Society for the Study of Reproduction, Inc.Öğe Synchronization of estrus in cows using double PGF2?, GnRH-PGF2? and hCG-PGF2? combination(2003) Çoyan K.; Ataman M.B.; Erdem H.; Kaya A.; Kasikci G.The aim of this study was to compare the effectiveness of treatments combining GnRH and PGF2? hCG and PGF2? combinations, and double PGF2? administration for synchronization of estrus in cows. This study was carried out in 30 Brown Swiss cows, aging 3 - 5 years. The cows were randomly divided into three groups. In group I (n = 10), the cows were treated with an intramuscular injection of 20 ?g GnRH (day = 0) at a random stage of the estrous cycle followed by intramuscular injection of 0.150 mg PGF2? 7 days later (day = 7). In group II (n = 10), the cows were treated with an intravenous injection of 3000 IU hCG (day = 0) at a random stage of the estrous cycle followed by intramuscular injection of 0.150 mg PGF2? 7 days later (day = 7). In group III (n = 10), the cows were received two injections of 0.150 mg PGF2? 11 day apart (day = 0, and 11). GnRH (10 ?g) was injected intramuscularly to the cows 48 hours after the injection of PGF2? in the groups I and II, and after the second PGF2? in group III. The cows were inseminated 12 hours after the GnRH injections. Blood samples were collected daily to determine plasma progesterone levels for 13 days in the groups I and II, and for 15 days in the group III starting from the day of GnRH, hCG and first PGF2? injections respectively. The mean interval injections-estrus, injections-ovulation, synchronization and pregnancy rates of the groups were determined. Plasma progesterone levels on day 0 and at estrous were similar among the three groups, but it was significantly higher (p < 0.01) in the groups I and II than in the group III on the day of PGF2? administration. The mean GnRH injections-estrus and injections-ovulation interval in the groups I, II and III were 52.2 ± 1.69, 48.4 ± 1.34 and 68.2 ± 1.31 hours; 70.4 ± 1.17, 67.3 ± 1.36 and 90.6 ± 2.15 hours, respectively and were significantly different (p < 0.01). The synchronization rates tend to be higher in the groups I and II (100%) than in the group III (80%), and pregnancy rates of the groups I, II and III were 60%, 60% and 30%, respectively. As a conclusion, application of a GnRH and hCG analogue prior to synchronization of estrus with an injection of PGF2? may provide better results than two injections of PGF2? for estms synchronization in cows.
