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Öğe Blood type A and B frequencies in Turkish Van and Angora cats in Turkey(Blackwell Verlag Gmbh, 2003) Arikan, S; Duru, SY; Gurkan, M; Agaoglu, ZT; Giger, UBlood typing of domestic cats has been performed in domestic and purebred cats in various parts of the world and is important in clinical practice in order to prevent neonatal isoerythrolysis (NI) and acute haemolytic transfusion reactions. Prevalence of blood types vary greatly between breeds of cats. Turkish Van and Angora cats are different breeds that originated in geographically distinct regions of Turkey. The present survey determined the frequency of blood types in these Turkish pedigreed cats in Turkey. Ethylenediaminetetraacetic-acid anti-coagulated blood of a total of 113 Turkish Van and Angora cats were examined for blood typing using a slide and tube agglutination assay. Of the 85 Van cats surveyed, 40% had type A, and 60% had type B blood. Of the 28 Turkish Angora cats, 53.6% had type A, and 46.4% had type B blood. No type AB cats were found between both breeds. There was no significant association between blood types and gender of both Angora and Van cats or eye colours of Van cats (P > 0.05). Although these are limited surveys, the overall prevalence of type B cats in these two breeds was very high compared with the results of previous studies worldwide. It appears likely that blood type incompatibilities responsible for feline NI and transfusion reactions are occurring in these breeds. The risk of transfusion incompatibility in Turkish Angora and Van cats was 46.4 and 60%, respectively. It is therefore strongly recommended to breeders and clinicians that blood typing be performed prior to breeding and transfusing cats.Öğe Changes in the size distribution of goat steroidogenic luteal cells during pregnancy(Elsevier Science Bv, 2003) Arikan, S; Yigit, AAExperiments were conducted to investigate the size distribution of goat steroidogenic luteal cells throughout pregnancy. Corpora lutea were collected from very early (<6 weeks), early (6-8 weeks), middle (9-14 weeks) or late (15-18 weeks) stages of pregnancy. Luteal tissue was dissociated into single-cell suspension by enzyme treatments. Cells were stained for 3beta-hydroxysteroid dehydrogenase (3beta-HSD) activity, a marker for steroidogenic cells. The steroidogenic cells covered a wide spectrum of size ranging from 5 to 45 mum in diameter. There was a significant increase in mean cell diameter (P > 0.01) as pregnancy progressed. Mean diameter of 3beta-HSD positive cells increased from 14.73 +/- 0.35 mum in the corpus luteum of very early pregnancy to 24.20 +/- 0.45 mum in the corpus luteum of late pregnancy. The ratio of large (>20 mum in diameter) to small (5-20 mum in diameter) luteal cells was 0.28:1.0 in very early pregnancy, with the 7.5-15 mum cell size class being dominant. However, the ratio of large-to-small luteal cells was increased to 1.77:1.0 mum as pregnancy advanced and 25-35 mum cell sizes became predominant. It is likely that small luteal cells could develop into large cells as pregnancy progresses. Development of pregnancy is also associated with an increase in size of steroidogenic luteal cells. (C) 2002 Elsevier Science B.V. All rights reserved.Öğe Changes in the size distribution of steroidogenic and non-steroidogenic bovine luteal cells during the oestrus cycle(Scientific Technical Research Council Turkey, 2001) Yigit, A; Arikan, SThe aim of this study was to investigate the size distribution of steroidogenic and non-steroidogenic luteal cells throughout the oestrus cycle. Twelve corpora lutea collected from different stages of the oestrus cycle were used. Corpora lutea collected from nonpregnant cows were dissociated into single-cell suspensions by enzyme treatments. Cells were stained for 3 beta -hydroxysteroid dehydrogenase (3 beta -HSD) activity, a marker for steroidogenic cells. The sizes of 3 beta -HSD positive (steroidogenic) and negative cells (nonsteroidogenic) were measured with an ocular micrometer. Very small cells (<10 m) stained negative for 3 beta -HSD activity were presumed to be primarily endothelial cells, fibroblast and blood cells. The other cells were presumed to be luteal cells covering a wide spectrum of size ranging from 10 to 40 mum in diameter. 3 beta -HSD positive cells smaller than 10 mum were not observed, and cells larger than 25 mum were rare. The cells obtained from early and late stages of the luteal phase contained more non-steroidogenic cells than the cells obtained from the mid-luteal phase. However, the cells derived from early luteal stage contained more small cells (10-22 mum) than the cells obtained from the rest of the cycle. There were significant differences (p < 0.001) in both 3-HSD positive and 3 beta -HSD negative cell sizes during the oestrus cycle. This study indicates that the size distributions of both steroidogenic and non-steroidogenic luteal cells change as the age of the corpus luteum increases.Öğe Effect of cyclodextrin-encapsulated β-carotene on progesterone production by bovine luteal cells(Elsevier Science Bv, 2000) Arikan, S; Rodway, RGExperiments were conducted to examine the effect of cyclodextrin-encapsulated beta -carotene on basal or cholesterol (cyclodextrin-encapsulated), LH and dibutyryl cyclic AMP (dbcAMP)stimulated progesterone production by bovine corpus luteum cells isolated from mid-luteal heifer ovaries by collagenase digestion. Cells were cultured with serum-free DMEM/Ham's F12 medium in serum pre-treated plastic culture dishes for periods of up to 11 days. Medium was replaced after 24h and thereafter every 48h. beta -carotene was added to cultures in a carrier molecule, dimethyl-beta -cyclodextrin, to facilitate dissolution. All treatments were started on day 3 of culture. Treatment of cells with 1 or 2 mu mol/l beta -carotene resulted in sharp inhibition of progesterone production. On the contrary, treatment of cells with 0.1 mu mol/l beta -carotene resulted in significant stimulation (P < 0.05) of both basal and cholesterol-stimulated progesterone secretion. The effect of -carotene on LH or dbcAMP-stimulated progesterone production was also examined. Treatment of cells with LH or dbcAMP always resulted in stimulation of progesterone secretion (P < 0.001). However, cells treated with LH plus -carotene or dbcAMP plus beta -carotene both produced significantly (P < 0.01) less progesterone relative to those cells treated with LH or dbcAMP alone on days 7, 9 and 11 of culture. These results indicate that -carotene can enhance luteal steroidogenesis when present at low concentrations but is inhibitory at higher concentrations and that encapsulation of beta -carotene in cyclodextrin is an effective method of supplying it to cells in culture. (C) 2000 Elsevier Science B.V. All rights reserved.Öğe Effect of pre-haemolytic concentrations of alpha, beta and gamma cyclodextrins on the osmotic fragility of dog erythrocytes(Ecole Nationale Veterinaire Toulouse, 2004) Arikan, S; Yigit, AA; Zengin, NKnowledge of the adverse effects of cyclodextrins on erythrocytes is important in view of the growing number of their potential applications in food, cosmetic, drug and chemical industries to increase aqueous solubility and stability, and reduce or eliminate the unpleasant taste and smell of many products. The experiment was conducted to examine the effect of pre-haemolytic concentrations of alpha-, beta- and gamma-cyclodextrins on the osmotic fragility of erythrocytes. Blood samples collected from 8 healthy Turkish Kangal dogs were analysed within 3 It of collection. Erythrocyte suspensions were mixed with various concentrations of alpha-, beta-, or gamma-cyclodextrins. The mixtures were then incubated for 30 min at 37 degreesC and osmotic fragility of erythrocytes was measured. Incubation of the erythrocyte suspensions with the all three cyclodextrins induced a dose-dependent increase in the osmotic fragility of erythrocytes. Initial haemolysis (10%) in alpha-, beta-, and gamma-cyclodextrin treated groups was at 8, 4 and 46 mM cyclodextrin concentrations, respectively. In conclusion, these results indicate that pre-haemolytic concentrations of all three cyclodextrins studied might induce membrane disruption, that may cause removal of membrane components from erythrocytes. When cyclodextrins are even used in a pre-haemolytic concentrations, it might reduce life span of erythrocytes.Öğe Effects of high density lipoprotein containing high or low β-carotene concentrations on progesterone production and β-carotene uptake and depletion by bovine luteal cells(Elsevier Science Bv, 2000) Arikan, S; Rodway, RGLuteal cells were isolated from mid-luteal heifer ovaries by collagenase digestion. Cells were cultured with DMEM/Ham's F12 medium in serum pre-treated plastic culture dishes for periods of up to 11 days. As beta-carotene is almost completely insoluble in all polar solvents, it was added to cultures in either dimethyl sulphoxide (DMSO), tetrahydrofuran (THF) or as high-density lipoprotein (HDL) containing high or low beta-carotene concentrations. Medium was replaced after 24 h, thereafter medium was changed every 48 h, Treatment of cells with DMSO alone or with beta-carotene (5 mu mol/l) in DMSO both resulted in significant (P < 0.01) stimulation of progesterone production. beta-Carotene (5 mu mol/l) in THF did not alter progesterone production but 50 mu mol/l beta-carotene in TNF resulted in significant inhibition (P < 0.02) of progesterone production on days 3 and 7, Cultures were also supplemented with bovine HDL preparations containing equal concentrations of cholesterol (25 mu g/ml) but high or low beta-carotene (12.4 or 0.44 mu g/mg of cholesterol). Both HDL preparations significantly stimulated progesterone production (P < 0.001) but the high beta-carotene HDL was significantly (P < 0.02) more effective than the low beta-carotene HDL. However, when given together with bovine luteinizing hormone (bLH) or dibutyryl cAMP (dbcAMP), the high beta-carotene HDL stimulated progesterone production less than did the low NDL (P < 0.01). Uptake and depletion of beta-carotene by luteal cells were also examined in culture, beta-carotene supplementation increased luteal cell beta-carotene from an initial level of 373 ng per 10(6) cells to 2,030 ng per 10(6) cells by day 6. In contrast, the levels in control cells decreased to 14% of starting values during the same period. Cells treated with HDL containing high p-carotene on day 1 or days 1 and 3 were then incubated with or without bLH or dbcAMP for a further 2 days to investigate the effect of bLH and dbcAMP on depletion of beta-carotene by luteal cells, beta-Carotene depletion in the luteal cells was significantly higher (P < 0.05) in LH- and dbcAMP-treated cells than in the control cells in both groups. These results indicate that the use of solvents such as DMSO or THF may have undesirable effects due to alteration of cell membrane permeability. Supplementation with bLH or dbcAMP may increase the metabolism of beta-carotene in luteal cells, bLH or dbcAMP together with high beta-carotene WDL may, when combined with the effect of increased beta-carotene metabolism, give less stimulation than with low beta-carotene HDL. (C) 2000 Elsevier Science B.V. All rights reserved.Öğe Size distribution of bovine steroidogenic luteal cells during pregnancy(Cambridge Univ Press, 2001) Arikan, S; Yigit, AThis study was designed to investigate the size distribution of bovine steroidogenic luteal cells throughout pregnancy. Corpora lutea collected from three different stages of pregnancy were used. Luteal tissue was dissociated into single-cell suspension by enzyme treatments. Cells were stained for 3 beta -hydroxysteroid dehydrogenase (HSD) activity, a marker for steroidogenic cells. The steroidogenic cells covered a wide spectrum of size ranging from 10 to 60 mum in diameter. There was a significant increase in mean cell diameter (P > 0.05) as pregnancy progressed. Mean diameter of 3 beta -HSD positive cells increased from 17.03 (s.e.1.3) pm in the cot-pus luteum of early pregnancy to 33.38 (s.e. 2.4) mum in the corpus luteum of advanced pregnancy. The ratio of large (> 22 mum in diameter) to small (10 to 22 mum in diameter) luteal cells was 0.32 : 1.0 in the early pregnancy, with the 10 to 22 mum cell size class predominant. However, the ratio of large to small lacteal cells was increased to 6.49 : 1.0 mum as pregnancy advanced and 23 to 42 mum cell sizes become predominant. It is likely that small luteal cells develop into large cells as gestation progresses. Development of pregnancy is associated with an increase in size of steroidogenic luteal cells.Öğe Titres of naturally occurring alloantibodies against feline blood group antigens in Turkish Van cats(British Veterinary Assoc, 2004) Arikan, S; Akkan, HASeventy-eight Turkish Van cats were examined for alloantibody titres, of which 42.3 per cent had type A blood and 57.7 per cent had type B blood. No type AB cats were found. All type B cats (n=45) showed gross evidence of agglutinating anti-A antibody, with titres ranging from 2 to 256. Sixty-seven per cent of type B cats had anti-A antibody in their plasma, with titres ranging from 8 to 32. However, 13 per cent of type B cats had plasma alloantibody titres of less than 8 and 20 per cent had titres that were higher than 32. A total of 33 type A cats were also tested for anti-B alloantibody titres in their plasma. Among the type A plasma, gross agglutination at titres of 2 and greater than 2 were determined in 24 per cent and 36 per cent of samples, respectively. Microscopic agglutination was seen in an additional 18 per cent of plasma samples. There was no significant association between gender and plasma alloantibody titres of cats (P>0.05).
