Browsing by Author "Yalçin, S"
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Item Effect of maternal corticosterone on utilisation of residual yolk sac fatty acids by developing broiler embryoYalçin, S; Bagdatlioglu, N; Babacanoglu, E1. Increased concentrations of maternal corticosterone are deposited into egg yolk under stress conditions. This experiment investigated the effect of maternal corticosterone on yolk and yolk sac fatty acid profiles of eggs and developing broiler embryos. 2. At 42 weeks of age, 200 broiler breeder females were randomly divided into two groups: maternal corticosterone (MC): 2 mg/hen/d of corticosterone dissolved in 1 mL of 99% ethanol and mixed in the individual daily feed for a 14 d period, and control: 1 mL of ethanol added to the individual daily feed. Hens were inseminated, and eggs were collected daily from d 3 of corticosterone feeding to d 14 and incubated. Fatty acid profiles of egg yolk and yolk sac were analysed before incubation and at 12, 14, 18 and 21 d of incubation. 3. Yolk corticosterone concentrations were greater in MC eggs. Before incubation, eggs from MC had lower DHA (22 : 6 n-3) but higher stearic (18 : 0) and dihomo-gamma linolenic (20 : 3 n-6 Cis 8,11,14) acid content compared with the control. 4. Higher concentrations of stearic (18 : 0), elaidic (18 : 1 tr n-9), eicosenoic (20 : 1 n-9), eicosadienoic (20 : 2 n-6), dihomo-gamma linoleic (20 : 3 n-6) and arachidonic (20 : 4 n-6) acids and lower concentrations of myristic (14 : 0), palmitoleic (16 : 1 n-7), linoleic (18 : 2 n-6) and DHA (22 : 6 n-3) were found at different periods of incubation in the residual yolk sac of MC than from controls. 5. The results suggest that the preferentially selective absorption of fatty acids is related to specific tissue requirements.Item Acclimation to heat during incubation.: 1.: Embryonic morphological traits, blood biochemistry, and hatching performanceYalçin, S; Çabuk, M; Bruggeman, V; Babacanoglu, E; Buyse, J; Decuypere, E; Siegel, PBEggs obtained from broiler breeders at 32 (young), 42 (middle aged), and 65 wk (old) were used to measure the effects of heat acclimation during incubation on morphological, physiological, and metabolic traits at internal pipping (IP) and at hatch. All eggs were from the same stock, and hatching performance was also evaluated. Eggs from each breeder age were incubated at control (CONT) or 38.5 degrees C for 6 h daily from d 10 to 18 of incubation (HA). On d 10 after heat exposure and on d 14, absolute and proportional weights were significantly lower for HA than CONT embryos. By the time of hatching, HA chicks were heavier than CONT chicks, which suggested accelerated growth. This effect was consistent across ages. Liver and heart weights were lower for HA than CONT chicks. At IP, pH was similar for HA and CONT embryos, whereas pO(2) and Na+ were significantly higher and pCO(2), HCO3-, and K+ significantly lower for HA than CONT embryos. Blood pH was higher in embryos from older than for younger and mid-aged parents at IP. At hatch there was no effect of heat acclimation for blood HCO3-, Na+, and K+ levels, whereas plasma triglyceride and T-3 levels were higher and plasma uric acid, glucose, and lipid peroxidation levels were lower for HA than CONT chicks. Embryonic mortality was similar among parental ages for CONT. In contrast for HA, embryonic mortality from older parents was higher than for younger and middle-aged parents. A delay in external pipping and hatching time with high incubation temperature was consistent across the breeder ages. It was concluded that lower blood pCO(2), HCO3-, K+, and higher pO(2) at IP stage, plus increased plasma triglyceride concentrations at hatch, indicate adaptive responses of embryos.Item Acclimation to heat during incubation.: 2.: Embryo composition and residual egg yolk sac fatty acid profiles in chicksYalçin, S; Bagdatlioglu, N; Bruggeman, V; Babacanoglu, E; Uysal, I; Buyse, J; Decuypere, E; Siegel, PBThe aim of the research was to evaluate embryo composition and changes in egg yolk fatty acid composition during embryonic development as a function of incubation temperature and age of breeders. Eggs obtained from a common breeder stock at 3 ages: 32 (younger), 42 (mid age), and 65 (older) wk were divided into 2 groups and placed into 2 incubators: the control and the second where eggs were heat-acclimated (HA) at 38.5 degrees C for 6 h daily from d 10 to 18 of incubation. Body composition of embryos and chicks were measured on d 14, 18, and at hatch, respectively. Fatty acid profiles of yolk and residual egg yolk sac of chicks were analyzed before incubation and at hatch, respectively. Moisture content of embryos was highest on d 14 and then decreased regardless of parental age and incubation temperature. Moisture content of chicks at hatch from 42-and 65-wk parents were lower than those of chicks from 32-wk parents, whereas the trend in chick fat content was opposite. Incubation temperature had no effect on composition of chicks. Consistently lower cis-4,7,10,13,16,19-eicosapentaenoic (docosahexaenoic acid, DHA; 22: 6n-3) and cis-11,14,17-eicosatrienoic (20: 3n-3) fatty acids in the residual yolk sac of chicks than in egg yolks before incubation may have resulted from preferential uptake from the yolk. The DHA content in the residual yolk sac was considerably higher in chicks from older parents incubated at HA, whereas, in contrast, levels of 18: 3n-3 were lower. Also, chicks from younger parents in the HA treatment had lower transported 18: 3n-3 and higher levels of transported DHA. It may be concluded that this process observed during the high incubation temperature may be related to a protective strategy and thus contributes to postnatal heat adaptation.Item Acclimation to heat during incubation: 4. Blood hormones and metabolites in broilers exposed to daily high temperaturesYalçin, S; Bruggeman, V; Buyse, J; Decuypere, E; Çabuk, M; Siegel, PBThe objective of the present experiment was to study the effects of parental age and heat acclimation of embryos on blood metabolites and hormones of broilers exposed to daily cyclic ambient temperatures from d 21 to 42. Eggs obtained from 32 (younger), 42 (middle-aged), and 65 wk (older) breeders were divided into 2 groups. One group of eggs was incubated at control incubation temperature (ITCONT), whereas the second group was heat-acclimated at 38.5 degrees C for 6 h/d from d 10 to 18 of incubation (ITHA). Chicks were reared at standard brooding temperatures from 1 to 21 d. From d 21 to 42, half of broilers/incubation temperature/parental age was kept as the control (AT(CONT)), whereas the other half was exposed to daily cyclic heat treatment (AT(HIGH)) to impose a stress response. There was a reduction in plasma triiodothyronine (T-3) levels in ITHA broilers. On d 28, plasma T-3 levels were similar regardless of parental age of eggs incubated at ITCONT, whereas ITHA resulted in lower levels of T-3 in broilers from 65 wk parents. At the same age, AT(HIGH) reduced plasma triglycerides with the effect greater for ITHA than ITCONT broilers. Plasma uric acid was also lower for ITHA than ITCONT broilers for the offspring of 65 wk parents on d 28. There was an increase in plasma creatine kinase activity on d 42 in AT(HIGH) broilers regardless of parental age and incubation temperature. Plasma corticosterone was consistently lower for the ITHA than ITCONT treatment, being significant on d 21 and 42. It was concluded that these changes in blood metabolites and hormones may enhance the thermoregulatory ability of ITHA broilers when exposed posthatch to daily high temperatures.Item Pre- and postnatal conditioning induced thermotolerance on body weight, physiological responses and relative asymmetry of broilers originating from young and old breeder flocksYalçin, S; Özkan, S; Çabuk, M; Buyse, J; Decuypere, E; Siegel, PBThe present experiment was conducted to examine the effects of pre- and postnatal conditioning to induce thermotolerance in broilers hatching from eggs orginating from younger and older breeder flocks. From each flock, 500 eggs were randomly divided into 2 groups and incubated at standard (SIT) and high (HIT) temperatures. At hatch, chicks were allotted to 36 floor pens. At 5 d of age 3 pens per parent age per incubation temperature were heat conditioned (C) for 24 h. At 21 d of age, 3 pens per parent age per incubation temperature were kept under standard (S) rearing temperatures, whereas the remaining broilers (including C) were moved to a heated room (H). Thus, there were 3 groups from 21 to 49 d including S, H, and C+H. The results indicated that to incubate eggs from younger parents at HIT before conditioning at 5 d may reduce deleterious effects of heat stress on body weight at slaughter age. However, HIT temperature decreased slaughter weight of broilers from older parents regardless of rearing temperature. Although conditioning did not prevent increments in rectal temperatures of broilers after 1 wk of heat stress (28 d), adaptation occurred thereafter for broilers from younger parents but not for broilers from older parents. Incubation temperature had no effect on plasma glucose, creatine kinase, uric acid, or triiodo-tryronine (T-3) levels at d 21. There were no differences at 22, 25, or 28 d for T3 concentrations between the H and C+H groups. Overall relative asymmetry was not influenced by treatments on d 49. The results suggest that although pre- and postnatal conditioning may help broilers cope with heat stress, age of parent plays a major role in the ability of broilers to thermoregulate. This is especially the case for broilers originating from younger parents.Item Effects of interferon-α-2b and octreotide on healing of esophageal corrosive burnsKaygusuz, I; Çelik, O; Özkaya, Ö; Yalçin, S; Keles, E; Çetinkaya, TObjective. The aim of this study was to investigate the effect of interferon-alpha to 2b and octreotide on the treatment of esophagus corrosive burns. Method: The experimental study was performed on 63 rabbits. Burn was obtained by treating a segment, isolated in cervical esophagus, with NAOH. The rabbits were allocated into three groups (control, interferon, and octreotide). On the fourth, eighth, and 20th days, 7 rabbits randomly selected from each group were killed. Comparisons among the groups were made by taking histopathologic findings, stenosis index, and hydroxyproline production into consideration. Cross-tabulation and analysis of variance tests were used for statistical analysis. Results: There were no statistically significant differences among the groups in terms of epithelial changes, extension of inflammation, and severity of fibrosis. In terms of severity of inflammation, there was a statistically Significant difference between the control and the other two groups. Also, a significant difference was found between the control group and the other two groups in terms of extension of fibrosis on the 20th day. The difference between the control and the two treatment groups was significant on the eighth day and the 20th day measurements. Comparison of the hydroxyproline values showed a statistically significant difference between the octreotide group and the other two groups on the eighth and 20th days. Conclusion: Histopathologic and biochemical findings indicate that, by hindering fibrosis progress, octreotide (and interferon) might be new and promising alternatives in the treatment of corrosive burns of the esophagus.Item Clinical outcomes of cyclin-dependent kinase 4-6 (CDK 4-6) inhibitors in patients with male breast cancer: A multicenter studyYildirim, HC; Mutlu, E; Chalabiyev, E; Özen, M; Keskinkiliç, M; Ön, S; Çelebi, A; Dursun, B; Acar, O; Kahraman, S; Aykan, MB; Kaman, O; Dogan, A; Erdogan, AP; Celayir, OM; Günenç, D; Güven, DC; Bayoglu, IV; Yavuzsen, T; Hacibekiroglu, I; Inanç, M; Kiliçkap, S; Yalçin, S; Aksoy, SBackground: Since breast cancer is less common in men than in women, data on the use of new therapeutic agents, including cyclin-dependent kinase 4-6 (CDK 4-6) inhibitors, are limited in patients with metastatic hormone receptor positive (HR+), human epidermal growth factor receptor 2-negative (HER2-) male breast cancer. Therefore; we aimed to investigate the treatment responses of metastatic HR+, HER2-male breast cancer patients treated with CDK 4-6 inhibitors in a multicenter real-life cohort. Methods: Male patients with a diagnosis of HR+ and HER2-metastatic breast cancer, treated with any CDK 4-6 inhibitor, were included in the study. Demographic and clinical characteristics of the patients were recorded. We aimed to determine progression-free survival (PFS) time, response rates and drug related side effects. Results: A total 25 patients from 14 institutions were recruited. The mean age at diagnosis was 57 years. Median follow-up was 19.53 (95% CI: 14.04-25.02) months. The overall response rate was 60%. While the median PFS was 20.6 months in the whole cohort, it wasn't reached in those using CDK 4-6 inhibitors in first line and 10 months in the subsequent lines (p:0.009). No new adverse events were encountered. Conclusion: In our study, we found that CDK 4-6 inhibitors are effective and safe options in men with HR+ and HER2-metastatic breast cancer as in women. Our results support the use of CDK 4-6 inhibitor-based combinations in the first-line treatment of HR+ and HER2-metastatic male breast cancer.Item Dietary vitamin E (α-tocopherol acetate) and selenium supplementation from different sources: performance, ascites-related variables and antioxidant status in broilers reared at low and optimum temperaturesÖzkan, S; Malayoglu, HB; Yalçin, S; Karadas, F; Koçtürk, S; Çabuk, M; Oktay, G; Özdemir, S; Özdemir, E; Ergül, M1. This study compared the effect of dietary supplementation with organic or inorganic selenium (Se) sources plus control amounts or large amounts of vitamin E (alpha- tocopherol acetate) in broilers raised at control ( 20 to 24 degrees C) or low ( 14 center dot 5 to 16 center dot 8 degrees C) temperatures after 2 weeks of age. 2. The following dietary treatments were used from one day old. Diet 1, the control diet, comprised a commercial diet containing 0 center dot 15 mg/ kg inorganic Se and 50 mg vitamin E/kg feed. Diet 2 was the same as diet 1, supplemented with 0 center dot 15 mg/ kg inorganic Se. Diet 3 was the same as diet 2 but was supplemented with 200 mg/ kg vitamin E. Diet 4 was the same as diet 1, but inorganic Se was replaced with 0 center dot 30 mg/ kg organic Se. Diet 5 was the same as diet 4, supplemented with 200 mg/ kg vitamin E. 3. Low temperature reduced the growth rate of broilers; however, at 6 weeks, there were no differences in the body weights of birds fed on organic Se supplemented diets housed at low or control temperature. The feed conversion ratio was significantly affected by low temperature but not by diet. The heterophil/ lymphocyte ratio was higher in chicks after one week in the cold, indicating mild stress. Blood triiodothyronine levels were significantly higher in birds after 1 and 4 weeks in the cold but thyroxin was not affected. 4. Organic Se supplementation increased relative lung weight at the control temperature, which might lead to greater respiratory capacity. Relative spleen weight significantly decreased in broilers fed diets supplemented with inorganic Se under cold conditions, a possible indication of chronic oxidative stress. 5. At the low temperature, supplementation with organic Se alone, or with inorganic Se and vitamin E increased glutathione peroxidase ( GSHPx) activity and glutathione ( GSH) concentration in the liver of broilers, which may indicate increased activity of birds' antioxidant defence against suboptimal environments.Item The efficacy of palbociclib and ribociclib in the first-line treatment of metastatic hormone receptor-positive, human epidermal growth factor receptor 2-negative breast cancer in male patients: a Turkish oncology group (TOG) studyYildirim, HÇ; Kutlu, Y; Mutlu, E; Aykan, MB; Korkmaz, M; Yalçin, S; Sakalar, T; Celayir, ÖM; Kayikçioglu, E; Aslan, F; Hafizoglu, E; Altintas, YE; Keskinkiliç, M; Chalabiyev, E; Çelebi, A; Dursun, B; Kapar, C; Özen, M; Acar, O; Dülgar,Ö; Kut, E; Biter, S; Kus, F; Almuradova, E; Erdogan, AP; Saray, S; Güven, DC; Simsek, ET; Üskent, N; Kemal, Y; Çakar, B; Acikgöz,Ö; Kiliçkap, S; Aksoy, SIntroductionMale breast cancer, comprising approximately 1% of all breast cancer cases, often leads to the exclusion of male patients as a criterion in clinical trials. While the efficacy of Cyclin-dependent kinases 4 and 6 (CDK 4/6) inhibitors has been established in metastatic hormone receptor-positive (HR +) and human epidermal growth factor receptor 2-negative (HER2 -) breast cancer in women, limited data exist on their effectiveness in male patients.We aimed to evaluate the efficacy and safety of palbociclib or ribociclib in male patients with breast cancer.IntroductionMale breast cancer, comprising approximately 1% of all breast cancer cases, often leads to the exclusion of male patients as a criterion in clinical trials. While the efficacy of Cyclin-dependent kinases 4 and 6 (CDK 4/6) inhibitors has been established in metastatic hormone receptor-positive (HR +) and human epidermal growth factor receptor 2-negative (HER2 -) breast cancer in women, limited data exist on their effectiveness in male patients.We aimed to evaluate the efficacy and safety of palbociclib or ribociclib in male patients with breast cancer.MethodsThis study is a multicenter, retrospective study. We included male patients with HR + and HER2-metastatic breast cancer who received palbociclib or ribociclib as first-line treatment. Our primary endpoints were progression-free survival (PFS), overall response rates (ORR), and drug-related adverse effects.ResultsA total of 46 male patients from 27 institutions were enrolled. The median age at initiation of CDK 4/6 inhibitors was 63.64 +/- 13.69 years, with a median follow-up of 21.33 (95% CI 14.92-27.74) months. The ORR were 84% for palbociclib and 76.2% for ribociclib. The mPFS for the entire cohort was 28.06 months (95% CI 18.70-37.42). No significant difference in PFS was observed between palbociclib and ribociclib (mPFS: 24.46 months (95% CI 11.51-37.42) vs 28.33 months (95% CI 14.77-41.88), respectively, p = 0.211). No new adverse events were reported.DiscussionThis study demonstrates that palbociclib and ribociclib are effective and safe options for first-line treatment in male patients with HR + /HER2 - metastatic breast cancer. However, further prospective studies are warranted to establish their efficacy in this population.