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Öğe Activity of 3 beta-hydroxysteroid dehydrogenase associated with progesterone production in bovine granulosa cells cultured under different concentrations of serum, insulin-like growth factor I, and gonadotropin(Scientific Technical Research Council Turkey-Tubitak, 2014) Simsek, Ozkan; Mihm, MonikaThree-beta-hydroxysteroid dehydrogenase (3 beta-HSD) is the enzyme responsible for progesterone production. This study aimed to determine whether 3 beta-HSD activity can be shown to reflect progesterone production by granulosa cells cultured under different serum conditions and follicle stimulating hormone (FSH), luteinising hormone (LH), and insulin-like growth factor I (IGF-I) concentrations. Large bovine follicles were dissected from abattoir ovaries to recover granulosa cells. Cells were washed, stained for viability, and plated for 48 h in basic medium with or without 5% foetal calf serum (FCS). Subsequently, cells were exposed to FSH (1 ng/mL), LH (10 or 100 ng/mL), or FSH (1 ng/mL) + IGF-I (1 or 10 ng/mL) in a serum-free medium for another 96 h to predict degree of luteinisation. Before and after incubation, granulosa cells were stained for 3 beta-HSD activity. The high dose of IGF-I (10 ng/mL) increased (P < 0.05) progesterone secretion over 2.5-fold compared with FSH alone or the low dose of IGF-I (1 ng/mL) in cells preincubated with FCS. This was clearly reflected by darker 3 beta-HSD staining than in cells exposed to FSH and low dose IGF-I.Öğe Comparing levels of certain heavy metals and minerals and antioxidative metabolism in cows raised near and away from highways(Scientific Technical Research Council Turkey-Tubitak, 2015) Ekici, Husamettin; Simsek, Ozkan; Arikan, Sevket; Eren, Meryem; Guner, BayramThe scope of this study was to investigate the concentrations of certain heavy metals, mineral levels, and antioxidative metabolism in cows raised near (300 m) and away from highways (2.5 km) in Cankiri Province. For this purpose, blood samples were collected from 100 cows (aged 3-5 years) raised near and away from highways in this province. Concentrations of certain heavy metals and minerals in the serum were analyzed on an ICP-MS device. Additionally, lipid peroxidation product malondialdehyde (MDA) in the plasma and antioxidative defense system indicators, erythrocyte superoxide dismutase (SOD) and catalase (CAT) activities, were measured with a spectrophotometer. As a result, levels of certain heavy metals and minerals and antioxidative status were determined in cows raised near and away from highways. Aluminum, iron, nickel, and zinc levels in the cows raised near highways were significantly different from those of the cows raised away from highways. Furthermore, MDA concentrations and SOD activities were significantly different between the two groups. It is concluded that monitoring the concentration of these heavy metals periodically may be useful to increase the productivity of cows.Öğe Determination of alpha-naphthyl acetate esterase (ANAE) activity in peripheral blood leukocytes of pregnant, adult, and kitten Angora cats(Scientific Technical Research Council Turkey-Tubitak, 2015) Bayraktaroglu, Alev Gurol; Simsek, Ozkan; Kurum, Aytul; Arikan, Sevket; Ergun, EmelThis study aimed to determine the alpha-naphthyl acetate esterase (ANAE) activity of peripheral blood leukocytes in pregnant, kitten, and adult Angora cats. In each group 9 healthy pregnant, adult, and kitten Angora cats constituted the material of the study. Optimum reaction was achieved after a 3 h incubation period at pH 5.8, by ANAE staining. Two types of reaction were observed in ANAE (+) T lymphocytes. The first reaction was a dot-like positivity pattern characterized by the presence of large granules, while the other was a granular positivity pattern characterized by the presence of 3 to 5 small granules. B lymphocytes reacted negatively in ANAE staining. The rate of ANAE (+) lymphocytes in pregnant, kitten, and adult Angora cats was 62.89 +/- 1.29%, 68.37 +/- 1.22%, and 77.71 +/- 1.63%, respectively. In conclusion, the lowest rate of ANAE-positive lymphocytes was detected in the pregnant cats, depending on the maternal immune tolerance supported by hormonal mechanisms. An increased rate of ANAE-positive lymphocytes was detected in the kittens, and the highest rate was measured in the adults, in parallel with the development of the immune system.Öğe Effect of the Incubation Time and High Dose Lead Application on Steroidogenic Luteal Cell Numbers(Wiley-Blackwell, 2016) Bilmen, Fatih Sultan; Kabakci, Ruhi; Arikan, Sevket; Simsek, Ozkan…Öğe Effects Of Acetamiprid, Methomyl, And Deltamethrin On Steroidogenesis In Cultured Bovine Luteal Cells(Parlar Scientific Publications (P S P), 2017) Arikan, Sevket; Simsek, Ozkan; Kalender, Hakan; Essiz, Dinc; Atmaca, Nurgul; Kabakci, Ruhi; Bilmen, Fatih SultanAcetamiprid, methomyl, and deltamethrinare widely used insecticides in agriculture and industry; thus, livestock may receive substantial exposure to such substances. This study was designed to evaluate the effect of these agents on bovine luteal cell steroidogenesis.Cells were incubated with acetamiprid (0.1 mM, 1 mM, or 10 mM), methomyl (0.1 mM, 1 mM, or 10 mM), or deltamethrin (0.01 mM, 0.1 mM, or 1 mM) for 5 days. Incubation with 1 mMacetamiprid resulted in significantly reducedpro-gesterone production by day 5. Incubation with 1 mM methomyl had no effect on progesterone pro-ductionby day 3 but did result in significant inhibi-tionby day 5. Incubation in 0.1 mM and 1 mMdelta-methrin resulted in significant reduction on both days 3 and 5. All three insecticides diminish luteal progesterone synthesis, with rank order methomylÖğe The effects of LH on progesterone production by cell subpopulations isolated from early and late luteal phase goat corpora lutea(Scientific Technical Research Council Turkey-Tubitak, 2014) Kalender, Hakan; Arikan, Sevket; Simsek, OzkanThe objective of this study was to investigate the complementary effects of luteinizing hormone (LH) on cell subpopulations. Corpora lutea were collected on days 5 and 15 of the cycle. The luteal tissues were treated with collagenase for cell dissociation. Percoll density-gradient centrifugation was performed to separate cells into 2 distinct subpopulations. Luteal cells (5 x 104 cells/well) were cultured with and without 22(R)-hydroxycholesterol (22R-HC, 10 mu g/mL) and LH (10 and 100 ng/mL) alone, and also with 22R-HC (10 mu g/mL) plus LH (10 and 100 ng/mL), in a serum-free culture medium for 6 days of incubation. Untreated cells isolated from luteal tissue collected on day 15 of the estrous cycle produced more steroids than those collected on day 5. Treatment of the cells with LH resulted in a significant (P < 0.05) increase in steroid synthesis on both days 5 and 15 of the cycle. Throughout the 7 days of incubation, 22R-HC caused a significant increase in progesterone production compared to untreated controls and to the LH treatments (P < 0.01). As a result, it appears that LH is mainly effective on small luteal cells in both the early and late luteal stages in goats.Öğe Effects of mancozeb, metalaxyl and tebuconazole on steroid production by bovine luteal cells in vitro(Elsevier Science Bv, 2018) Atmaca, Nurgul; Arikan, Sevket; Essiz, Dinc; Kalender, Hakan; Simsek, Ozkan; Bilmen, Fatih Sultan; Kabakci, RuhiMancozeb, metalaxyl and tebucanazole are widely used pesticides in agriculture and industry to treat plant pathogenic fungi. Livestock may be exposed to such substances by consuming contaminated plants. The present study was designed to evaluate the effects of these three fungicides on bovine luteal cell steroidogenesis. Luteal slices from mid-cycle corpus luteum were dissociated into single cell suspension in aerated (02) culture media (DMEM/F12) by enzymatic digestion. The cells were incubated in newborn calf serum (10%) for 18 h and then with serum-free media containing mancozeb (0.01 mu M, 0.1 mu M, 1 mu M), tebuconazole (1 mu M, 10 mu M, 100 mu M) or metalaxyl (100 mu M, 500 mu M, 2500 mu M) for additional 96 h. The medium was replaced on day 1 and 3; and the retrieved medium was stored at - 20 degrees C until progesterone assay. Treatment of cells with three different fungicides induced dose dependent variable decrease in steroid synthesis during incubation periods. Incubation of cells with 1 pM mancozeb exhibited a 33% decline in steroid synthesis on day 3 and 48% decline on day 5 compared with controls. Treatment of cells with 100 M tebuconazole and 500 mu M metalaxyl resulted in a 65% and 31% decrease, respectively, in progesterone accumulation on day 5 of incubation. Fungicide induced suppressive effects on luteal steroidogenesis were as metalaxyl < tebuconazole < mancozeb. Results of the present study suggest that designated concentrations of all three fungicides studied might have varying degrees of adverse effects on luteal steroidogenesis.Öğe Effects of selected fungicides on steroid synthesis by bovine luteal cells(Wiley-Blackwell, 2016) Atmaca, Nurgul; Arikan, Sevket; Essiz, Dinc; Kalender, Hakan; Simsek, Ozkan; Bilmen, Fatih Sultan; Kabakci, Ruhi…Öğe Heavy metal accumulation and oxidative-antioxidative status in Angora goats depending on age(Parlar Scientific Publications (P S P), 2015) Simsek, Ozkan; Ekici, Husamettin; Cinar, Miyase; Atmaca, Nurgul; Arikan, Sevket; Guner, BayramThis study intends to designate the alterations in the oxidant-antioxidant parameters and the heavy metal concentrations based on age of Angora goats bred in Cankiri-province of Turkey. In order to conduct an analysis of serum heavy metals including aluminum (Al), chromium (Cr), iron (Fe), copper (Cu), cobalt (Co), tin (Sn), cadmium (Cd), selenium (Se), vanadium (V), manganese (Mn), zinc (Zn), lead (Pb), arsenic (As), nickel (Ni), a total of 120 blood samples were taken. Concentrations of plasma vitamin E, vitamin A and beta-carotene, concentration of malondialdehyde (MDA), activities of catalase (CAT) and superoxide dismutase (SOD) were evaluated in the erythrocytes. Correspondingly, compared to young goats, the adult goats had substantially higher levels of Al, V, Mn, Ni, As and Sn. With respect to the young goats, the vitamin E concentration and SOD activity measured in adult goats were lower and the MDA concentration was considerably higher. Consequently, it was seen that aging affected the oxidant-antioxidant parameters and heavy metal concentrations in Angora goats.Öğe In vitro Effects of Linuron on Luteal Progesterone Synthesis(Wiley-Blackwell, 2016) Bilmen, Fatih Sultan; Arikan, Sevket; Simsek, Ozkan; Atmaca, Nurgul; Kalender, Hakan; Essiz, Dinc; Kabakci, Ruhi…Öğe Reference values for selected hematological and biochemical blood parameters from prepregnancy to advanced gestation in Angora cats(Scientific Technical Research Council Turkey-Tubitak, 2015) Simsek, Ozkan; Arikan, Sevket; Cinar, MiyaseThe aim of this study was to monitor some hematological and biochemical blood parameters from prepregnancy to advanced gestation in Angora cats. In the present study, 35 blood samples obtained before and during pregnancy from 7 adult cats were used. Blood was collected from cats before pregnancy and on days 15, 30, 45, and 55 of gestation. The blood samples were analyzed in terms of WBC, RBC, Hb, PCV, MCV, MCH, MCHC, GRA, MON, and LYM values. Additionally, serum ALT, AST, ALP, GGT, LDH, and CK activities and total cholesterol, glucose, triglyceride, urea, Ca, Mg, and Pi levels were measured. Levels of leukocytes, MCHC, MCH, and MCV were lower, and RBC, PCV, and Hb levels were higher before pregnancy than on day 55 of gestation. Monocyte and glucose levels were higher before gestation than during pregnancy. Total cholesterol levels were lower before gestation than during gestation. Triglyceride and Mg levels with LDH activity were higher in the late stages of pregnancy than before gestation. In conclusion, in this study changes in selected hematological and biochemical blood parameters have been determined before and during pregnancy in Angora cats for the first time. The data presented in this research may be a useful reference for veterinarians practicing in clinics.Öğe Selected haematological and biochemical parameters in healthy Damascus goats(Wiley-Blackwell, 2015) Simsek, Ozkan; Atmaca, Nurgul; Guner, Bayram; Kabakci, Ruhi; Bilmen, Fatih Sultan…Öğe Some electrocardiographic values of Angora goats(Ankara Univ Press, 2014) Atmaca, Nurgul; Simsek, Ozkan; Emre, BahriElectrocardiography is a noninvasive and easily applied technique used in the determination of cardiac hypertrophy and dilatation, the classification of cardiac arrhythmias, and the diagnosis of conduction abnormalities. The aim of this study was to determine the normal electrocardiographic (ECG) values in Angora goats. A total of 30 healthy Angora goats of both sexes, ranging in age from 1 to 2 years, were used in the study. The 3 standard bipolar limb leads (I, II, III) and unipolar augmented limb leads (aVR, aVL, aVF) were recorded with the goats standing. The morphology and amplitude of P waves, QRS complexes, and T waves were analyzed in all leads. Cardiac rhythm, heart rate, and the durations of P, QRS and T waves, as well as the PR interval and QT interval, were calculated in the limb leads. The mean electrical axis for each individual was determined from the net amplitude of the QRS complex in leads I and III. Most of the animals had sinus rhythm. The mean heart rate was 108.71 +/- 3.289 per minute and ranged from 75 to 143. The mean electrical axis was between -178 degrees and +170 degrees. In conclusion, the findings presented here may be useful to clinicians and researchers as reference values for the normal ECG of Angora goats.Öğe Time- and Dose-dependent Effects of Lead on the Number of Cultured Granulosa Cells Showing Steroidogenic Activity(Wiley-Blackwell, 2016) Bilmen, Fatih Sultan; Simsek, Ozkan; Kabakci, Ruhi; Arikan, Sevket…
