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diversity of coronavirus in bats from eastern thailand.bats are reservoirs for a diverse range of coronaviruses (covs), including those closely related to human pathogens such as severe acute respiratory syndrome (sars) cov and middle east respiratory syndrome cov. there are approximately 139 bat species reported to date in thailand, of which two are endemic species. due to the zoonotic potential of covs, standardized surveillance efforts to characterize viral diversity in wildlife are imperative.201525884446
induction of ovulation by clomiphene citrate in the indian vespertilionid bat, scotophilus heathi.the ovulation induction property of clomiphene citrate (cc) and human chorionic gonadotropin (hcg) was studied in scotophilius heathi, an indian tropical vespertilionid bat, during the period of delayed ovulation between december to early january. the results of the study showed that 10 microg of cc alone was ineffective to induce ovulation, whereas 100 microg cc and 10 iu hcg alone induced ovulation. a significant (p < 0.01) increase in the ovulation rate was observed when 10 microg cc followed ...200010861555
effects of hcg and pmsg on responsiveness of ovary during period of delayed ovulation in an indian vespertilionid bat, scotophilus heathi.both hcg and pmsg treatments given either individually or sequentially between september and early february failed to induce ovulation in s. heathi, though they produced high degree of ovarian stimulation. the treatments induced ovarian enlargement, intense hyperaemia, marked changes in interstitial cells (ics) and development of several antral follicles and varying degrees of abnormality in oocyte of most of the antral follicles. the percentage of abnormal oocytes in the ovary following hcg or ...19921459645
sperm storage in the female reproductive tract of scotophilus heathii: role of androgen.the aim of the present study was to investigate the mechanism of androgen-mediated, prolonged sperm-storage in the female reproductive tract of the bat, scotophilus heathii. the bat treated in vivo with flutamide, an androgen antagonist, showed loss of spermatozoa at the storage site, utero-tubal junction. immunocytochemistry and western blot analysis revealed the presence of increased expression of bcl2 in the epithelial cell lining of the utero-tubal junction during the period of sperm-storage ...201121638510
ovarian androstenedione production is enhanced by insulin during the period of delayed ovulation in a vespertilionid bat, scotophilus heathi.the aim of the present study was to evaluate the role of insulin in the production of high concentrations of androstenedione in the ovary of scotophilus heathi during the period of delayed ovulation. the concentrations of serum insulin were found to be high during november and december and declined significantly before ovulation. a significant correlation was observed between circulating insulin concentration and body weight as well as with serum androstenedione concentrations. autoradiographic ...19989875156
changes in the expression of hsl and octn2 in the female reproductive tract of the bat, scotophilus heathii in relation to sperm storage.the aim of this study was to compare the changes in the expression of hormone sensitive lipase (hsl) and organic cation transporter 2 (octn2) in different regions of the female reproductive tract of bats (scotophilus heathii) during the period of sperm storage. western blot analysis revealed that both hsl and octn2 showed elevated expression in the utero-tubal junction, the site of sperm storage, compared to the vagina, cervix and uterus. an immunohistochemical study showed localization of hsl a ...201221820160
localization of adiponectin and its receptor and its possible roles in the ovary of a vespertilionid bat, scotophilus heathi.the aim of this study was to evaluate the seasonal variation in serum adiponectin levels and ovarian expression of adiponectin and its receptor in the scotophilus heathi bat and their relationship to the changes in the body fat mass, serum insulin and luteinizing hormone (lh) levels, and ovarian activity. a very high level of circulating adiponectin was found during recrudescence, whereas a very low level of circulating adiponectin was observed during pre-ovulatory period. the increased circulat ...201222342274
the relationship between spermatozoa and epithelium of the female genital tract during sperm storage in the greater yellow bats (scotophilus heathi): the light and electronmicroscopic observations.the present paper describes the relationship between spermatozoa and the epithelium of the female genital tract during sperm storage in greater yellow bats, scotophilus heathi. all the female bats collected from mid-january till ovulation in early march showed the presence of spermatozoa with their heads orientated towards the epithelial lining of the female genital tract. during this period, the epithelial cells of the uterine horn showed extensive endoplasmic reticulum (er), numerous mitochond ...19979208484
effects of adiponectin on ovarian folliculogenesis and steroidogenesis in the vespertilionid bat, scotophilus heathi.the bat scotophilus heathi undergo anovulation, known as delayed ovulation, coinciding with the period of seasonal adiposity due to fat accumulation. because adiponectin is a well known fat cell product, it might be responsible for adiposity related anovulation in s. heathi. the aim of this study was thus to evaluate the effects of adiponectin treatment on ovarian activity in s. heathi. the bat during the period of delayed ovulation was treated with adiponectin (25 μg/day) for 12 days. changes t ...201222796157
glycogen accumulation in the ovarian follicle of indian vespertilionid bat, scotophilus heathi during the period of delayed ovulation.massive accumulation of glycogen in the follicles of scotophilus heathi during the period of delayed ovulation was noticed. the follicles which survive for prolonged periods are morphologically specialized. the accumulation of glycogen was noticed in the granulosa cells. the egg cytoplasm, thecal cells and interstitial cells were almost devoid of glycogen. the first sign of a glycogen deposit in the ovary was noticed during the recrudescence phase (october) in late pre-antral follicles. most of ...19969107143
the expression pattern of the glucose transporter glut-5 in the testis during the spermatogenic cycle of the vespertilionid bat scotophilus heathi.the aims of this study were to investigate the localization and rate of expression of glut-5 protein during the spermatogenic cycle of scotophilus heathi and to determine whether the expression of testicular glut-5 was under androgenic control. this study showed localization of glut-5 mainly in the spermatogonia, spermatids, spermatozoa and leydig cells of the testis in s. heathi. western blot analysis showed marked variation in the rate of expression of glut-5 protein in the testis during the r ...201323751812
high androgen production by ovarian thecal interstitial cells: a mechanism for delayed ovulation in a tropical vespertilionid bat, scotophilus heathi.the steroid hormone profile of scotophilus heathi, and indian tropical vespertilionid bat, was studied, with special reference to the period of delayed ovulation. the results show unusually high concentrations of circulating androstenedione and testosterone during the first half of the period of delayed ovulation, whereas the concentrations of progesterone and oestradiol were relatively low during this period. androstenedione, testosterone and oestradiol concentrations were high during the perio ...19968699403
effects of seasonal adiposity on ovarian activity of vespertilionid bat, scotophilus heathi: proteomics analysis.in present study comparative proteomics was utilized to identify ovarian protein profiles and correlate the expression of these proteins with adiposity induced changes in ovarian activity leading to suppression of ovulation (delayed ovulation) in the bat, s. heathi. to achieve this, two-dimension gel electrophoresis combined with protein identification by tandem mass spectrometry (lc-ms/ms) was applied. protein profiles were obtained from intact ovaries of bats collected during recrudescence (ba ...201525305638
inhibitory effects of melatonin on testosterone but not on androstenedione production during winter in the vespertilionid bat, scotophilus heathi.the possible effects of melatonin on testosterone and androstenedione production in vitro by testes of wild-caught bats, scotophilus heathi, during different reproductive phases were investigated. bats were captured during reproductive quiescent (april-august), recrudescent (september-october), breeding (november-february), and winter dormancy (late december-january) phases. testes were incubated in media-199 for 2 h at 37 degrees c with luteinizing hormone (lh) and with or without melatonin. me ...19958750346
morphological changes of the rete system in the ovaries of adult bat, scotophilus heathi, during breeding cycle.the present study describes a well developed rete ovarii in the ovary of the adult indian vespertilionid bat, scotophilus heathi, and supports the role of the rete system in early follicular growth in the ovary. a close contacts between the rete tubules and follicles have been found at the beginning of the follicular growth in the mature ovary. ultrastructural features of connecting rete cells indicate the active protein synthesis, while those of intraovarian rete cells suggest their role in tra ...19937949402
localization of resistin and its possible roles in the ovary of a vespertilionid bat, scotophilus heathi.the aim of the present study was to evaluate the expression and effect of resistin on ovarian activities of scotophilus heathi. immunohistochemical study showed marked variation in resistin immunostaining during different reproductive phases. most intense immunostaining of resistin was noticed in thecal-interstitial cells in ovary during the period of delayed ovulation, the period of increased androgen synthesis and suppressed ovulation. the changes in ovarian resistin level also correlated posi ...201525555474
comparative studies of m4-purified lactate dehydrogenase (ld) from the liver of scotophilus heathi and cynopterus sphinx (micro- and mega- chiropteran bats). 19873607829
storage of spermatozoa in the female genital tract of the vespertilionid bat, scotophilus heathi.spermatozoa were observed in all parts of the genital tract in females killed in january, february, march and april although copulation occurs only until early february. the spermatozoa were arranged linearly with their heads orientated towards the epithelial lining.1978569203
viability of inseminated spermatozoa in the indian vespertilionid bat scotophilus heathi (horsefield). 1978568119
hormonal induction of ovulation stimulates atresia of antral follicles in a vespertilionid bat, scotophilus heathi.scotophilus heathi is a seasonally monoestrous subtropical vespertilionid bat found at varanasi, india. although the antral follicles remain present in the ovaries of s. heathi from november till march, ovulation is delayed in this species until early march. in order to understand the mechanism of ovulation suppression during this period of delayed ovulation, the effects of human chorionic gonadotropin (hcg), pregnant mare's serum gonadotropin (pmsg), follicle stimulating hormone (fsh) and gonad ...200616814533
pattern of ovarian protein synthesis and secretion during the reproductive cycle of scotophilus heathi: synthesis of an albumin-like protein.ovarian proteins synthesized de novo and secreted in vitro were investigated during different stages of the reproductive cycle of scotophilus heathi. we found increased ovarian protein synthesis and secretion during the recrudescence and the preovulatory periods, coinciding with two peaks of follicular development and steroidogenesis. the ovaries synthesized protein at a low rate during quiescence and the late phase of delayed ovulation. in vitro analysis using 35 s-methionine incorporation show ...200415621885
histochemical localization of enzymes and lipids in the ovary of a vespertilionid bat, scotophilus heathi, during the reproductive cycle.the present study describes seasonal changes in delta5 3beta hydroxysteroid dehydrogenase (3beta-hsd), glusose-6 phosphates dehydrogenase (g-6-pd), and lipids in the ovary of a vespertilionid bat, scotophilus heathi. total lipids and 3beta-hsd activity are restricted to thecal and interstitial cells of the ovary. the total lipids, 3beta-hsd, and g-6-pd significantly increase during recrudescence, and remain high during winter dormancy and breeding as compared to the other reproductive phases. hi ...200516025916
ovulation induction by antiestrogens in an indian tropical vespertillionid bat, scotophilus heathi.the ovulation induction property of ici 182,780 a pure antiestrogen and enclomiphene citrate (enc) was carried out in scotophilus heathi, an indian tropical vespertillionid bat, during december to february i.e., preovulatory period. this bat ovulates two ova naturally and shows ovulatory asynchrony. the study showed that 100 ìg of enc followed by 10 iu hcg resulted in significantly lower number of ovulation. whereas, the pure antiestrogen ici 182,780 at a dose of 100 ìg followed by 10 iu hcg res ...200616934298
adiposity associated rise in leptin impairs ovarian activity during winter dormancy in vespertilionid bat, scotophilus heathi.the aim of the study was to evaluate the seasonal variation in serum leptin levels in a natural population of the female bat, scotophilus heathi and their relationship to the changes in the body mass, serum insulin level, and ovarian activity. circulating leptin level varied significantly over the season and correlated positively with the changes in body mass, and circulating insulin and androstenedione (a4) levels. circulating leptin concentrations showed two peaks; one coincides with the maxim ...200717244743
seasonal adiposity, correlative changes in metabolic factors and unique reproductive activity in a vespertilionid bat, scotophilus heathi.the aim of this study was to determine the effect of changes in body mass, fat reserves and feeding activity on circulating levels of lipids, glucose, protein and metabolic hormones in a vespertilionid bat, scotophilus heathi. furthermore, the relationship between changes in metabolic factors and hormones with the unique reproductive features of female s. heathi was also examined. the results of this study showed annual variation in body mass, fat reserve and feeding activity, which correlated s ...200818203145
evidence of androgen-dependent sperm storage in female reproductive tract of scotophilus heathi.the aim of present study was to investigate the role of androgen in sperm storage in the female genital tract of scotophilus heathi. spermatozoa were observed in the distal part of oviduct and utero-tubal junction of all the female bats collected between january and early march. increase in circulating testosterone level coincided with the arrangement of sperm with their head oriented towards the epithelial lining of reproductive tract. immunocytochemical and western blot analysis revealed the p ...201019539620
melatonin affects steroidogenesis and delayed ovulation during winter in vespertilionid bat, scotophilus heathi.the aim of this study was to evaluate the role of melatonin in ovarian activity of scotophilus heathi particularly in reference to changes in steroidogenesis and steroid receptor expression during the anovulatory period of delayed ovulation. female s. heathi showed an increased circulating melatonin level during the period of delayed ovulation in winter coinciding with the increased androstenedione (a(4)) levels, body fat and ovarian androgen receptor expression. the circulating melatonin level ...201019897034
melatonin modulates glucose homeostasis during winter dormancy in a vespertilionid bat, scotophilus heathi.the role for melatonin in glucose homeostasis and insulin resistance is not very clear and has recently been an active area of investigation. the present study investigated the role of melatonin in seasonal accumulation of adipose tissue in scotophilus heathi, with particular reference to its role in glucose homeostasis and development of insulin resistance. the circulating melatonin levels correlated positively (p<0.05) with the changes in body mass due to fat accumulation and circulating insul ...201020026417
seasonal adiposity and androstenedione production as a possible mechanism for asynchronous reproductive activity between males and females of vespertilionid bat, scotophilus heathi.relationship between changes in the body weight and circulating androstenedione concentration was examined in order to find out their involvement in asynchronous gametic cycle of male and female s. heathi. body weight of both male and female bats increased from september due to accumulation of white adipose tissue and reached to a peak in november. the body weight declined gradually due to consumption of adipose tissue during december and january reaching basal level in february. a significant c ...200010866359
possibility of inhibin as a regulator of androstenedione production by the ovary during the period of delayed ovulation in a vespertilionid bat, scotophilus heathi.the aim of the present study was to evaluate the role of inhibin in regulating androstenedione production by the ovary of scotophilus heathi during the period of delayed ovulation. inhibin alone increased the androstenedione synthesis in vitro by the ovary during all reproductive phases, but augmented the hcg induced androstenedione production only during november. the follicles produced significantly higher androstenedione as compared to the stromal or granulosa cell in response to both hcg and ...199910530898
immunolocalization of cytochrome p450 side chain cleavage, 17-alpha-hydroxylase and aromatase in the ovary of vespertilionid bat (scotophilus heathi) during different phases of ovulatory delay.immunocytochemical localization of steroidogenic enzymes, cytochrome p450 side chain cleavage, 17-alpha-hydroxylase and aromatase, was performed in the ovaries of scotophilus heathi during reproductive cycle, with reference to the period of delayed ovulation. moderate immunoreactivity of side chain cleavage enzyme and 17-alpha-hydroxylase was observed mainly in thecal cells and interstitial cells of the ovarian stroma during quiescence. thecal cells positive for 17-alpha-hydroxylase were found e ...199810347746
changes in circulating insulin and corticosterone concentrations during different reproductive phases and their relationships to body weight and androstenedione concentration of male scotophilus heathi.the aim of the present study was to determine the serum levels of insulin and corticosterone during different reproductive stages in a natural population of the male bat, scotophilus heathi and their relationship to body weight and androstenedione level. changes in body weight were marked by weight gain before winter dormancy and weight loss during winter dormancy. circulating insulin level varied significantly over the season and correlated positively with changes in body weight and androstened ...19989621439
pituitary adrenocorticotrophic (acth) cells during reproductive cycle in a vespertilionid bat, scotophilus heathi.present study described the pituitary adrenocorticotropic (acth)-cells during different phases of reproductive cycle of indian vespertilionid bat, s. heathi. acth-cells were identified by histochemical, immunocytochemical and electron microscopic techniques. these cells shows round to polygonal in shape and be easily distinguished by histochemical staining. the body weight attains peak during recrudescence phase due to accumulation of fat. the mean areal fraction occupied by acth-cells were high ...19979847454
adiposity and androstenedione production in relation to delayed ovulation in the indian bat, scotophilus heathi.observations on body weight, circulating androstenedione concentrations and morphology of ovarian stroma were made in scotophilus heathi during the period of delayed ovulation to make a comparison with polycystic ovarian syndrome in women. body weight of bats increased from a level of 31.00 +/- 0.30 g in august and reached a peak of 45.00 +/- 0.46 g in november. this increase in body weight was due to accumulation of adipose tissue. the body weight declined gradually from december onwards and fi ...19979080676
seasonal changes in circulating serum concentration and in vitro testicular secretion of testosterone and androstenedione in the male vespertilionid bat (scotophilus heathi).seasonal changes in the testicular activity were studied in the male greater yellow bat, scotophilus heathi, in varanasi, india (25 degrees n, 83 degrees e). the seasonal pattern of body weight of male bats was also recorded and compared with circulating androstenedione (a) and testosterone (t) concentration. there was a gradual increase in the body weight of the bat from september onward mainly due to accumulation of adipose tissue. finally, body weight reached a peak level in november. two per ...19968828184
immunocytochemical studies on the pituitary pars distalis of the tropical vespertilionid bat, scotophilus heathi, with reference to the ovarian cycle.changes in the anterior pituitary in relation to the ovarian cycle and ovulation in female scotophilus heathi are described. tsh, lh, fsh and prl cells have been identified in the pars distalis (pd) by immunocytochemistry using the peroxidase-antiperoxidase technique. lh, fsh and prl cells exhibited significant variation during the reproductive cycle of female s. heathi. the areal fractions of the pd occupied by lh and fsh cells were significantly (p < 0.05) higher during winter dormancy and the ...19968828708
regulation of leptin synthesis during adipogenesis in males of a vespertilionid bat, scotophilus heathi.the aim of this study was to elucidate the hormonal regulation of leptin synthesis by the white adipose tissue (wat) during the period of fat accumulation in male scotophilus heathi. an in vivo study showed a significant correlation between the seasonal changes in serum insulin level with the circulating leptin level and with the changes in body fat mass in s. heathi. an in vitro study showed insulin induced a significant increase in expression of leptin protein in wat. the insulin-stimulated in ...201121490267
increased circulating leptin level inhibits folliculogenesis in vespertilionid bat, scotophilus heathii.the present study investigates the mechanism by which obesity associated rise in leptin and insulin levels cause anovulation in vespertilionid bat, scotophilus heathii. in the ovary of s. heathii, leptin and insulin receptors were mainly localized in interstitial and thecal cells and in the granulosa cells of primary follicles suggesting its possible role in androgen synthesis and follicular development. adiposity associated increase in circulating leptin level down regulate ovarian lh-receptor ...201121277349
role of leptin in seasonal adiposity associated changes in testicular activity of vespertilionid bat, scotophilus heathi.the aim of this study was to investigate changes in circulating level of leptin in natural population of male bat, scotophilus heathi in relation to seasonal changes in body mass, adipose tissue mass and testicular activity. the peak serum leptin level coincided with the period of maximum body mass due to heavy accumulation of adipose tissue. the in vivo study showed both inhibitory and stimulatory effects on testicular activity depending on circulating level of leptin. moderate increase in circ ...201020450917
changes in glucose and carnitine levels and their transporters in utero-tubal junction in relation to sperm storage in the vespertilionid bat, scotophilus heathi.prolonged sperm storage over winter is a common feature of reproduction in some bats. in order to understand how sperm storage in the female genital tract of the vespertilionid bat, scotophilus heathi (greater yellow bat), is controlled, we compared concentrations of glucose and the fatty-acid carrier carnitine in the blood, and carnitine concentrations and levels of expression of the glucose transporters (gluts) and the carnitine transporter octn2 in the utero-tubal junction of females during n ...201324039231
effects of resistin on ovarian folliculogenesis and steroidogenesis in the vespertilionid bat, scotophilus heathi.the bat scotophilus heathi exhibit prolonged anovulatory condition known as delayed ovulation coinciding with the period of extensive fat accumulation. the present study was undertaken to find out whether extensive accumulation of fat in s. heathi is responsible for suppression of ovarian activity by increasing production of adipokine resistin in the bat. this was achieved by (a) investigating variation in serum resistin level in relation to the changes in the body fat mass and (b) evaluating th ...201425241398
[the olfactory region of the bat scotophilus heathi. light and electron microscopic studies].the present investigation reports light and electron microscopical aspects of the main olfactory epithelium (moe) of the insectivorous bat scotophilus heathi. serial frontal sections of the nose and associated structures reveal: 1) that the moe is located on most of the ethmoturbinals and on the proximal upper portion of the nasal septum; and 2) that the vomeronasal organ is absent in this species. the ultrastructure of the moe of scotophilus heathi is similar to that observed in other vertebrat ...19921503239
the structure and histology of the tongue in two indian bats rhinopoma kinneari (rhinopomatidae) and scotophilus heathi (vespertilionidae). 19827084828
seasonal adiposity and delayed ovulation in a vespertilionid bat, scotophilus heathi: role of tumor necrosis factor-alpha.the aim of this article was to evaluate the physiological significance of tumor necrosis factor-alpha (tnf-alpha) in seasonal accumulation of adipose tissue, hyperinsulinemia, and anovulation in scotophilus heathi. the result showed seasonal variations in the circulating tnf-alpha level. a higher level of circulating tnf-alpha was observed during quiescence and recrudescence, whereas a lower level of tnf-alpha was observed during winter dormancy and the preovulatory period. an increased circulat ...201412794681
relationship between corticosterone and body weight, androstenedione and insulin during the period of delayed ovulation in a vespertilionid bat, scotophilus heathi.the aim of the present study was to evaluate the relationship between corticosterone, body weight, insulin and androstenedione in order to understand the role of adrenal in contributing hyperandrogenism during delayed ovulation in s. heathi. the circulating corticosterone concentration in female s. heathi showed significant seasonal variation. the peak corticosterone concentration observed during august-september coincides with increased feeding activities in s. heathi. the present study noted a ...200212371607
mechanism of delayed ovulation in a vespertilionid bat, scotophilus heathi: role of gonadotropin, insulin, and insulin-like growth factor-1.the aim of this study was to evaluate the effects of luteinizing hormone (lh), follicle-stimulating hormone (fsh), insulin, and insulin-like growth factor-1 (igf-1) on ovarian androstenedione synthesis to understand the mechanism responsible for delayed ovulation in scotophilus heathi. we found that lh stimulated a dose-dependent increase in androstenedione synthesis by the ovary in vitro. this study also showed a clear seasonal variation in the ability of the ovary to produce androstenedione in ...201411009407
coronaviruses in guano from pteropus medius bats in peradeniya, sri lanka.bats are a unique group of mammals well suited to be hosts for emerging viruses. with current rates of deforestation and urbanization, redistribution of bat habitats to urban and suburban areas may bring bats into closer contact with livestock and humans. common flying fox, pteropus medius (previously known as pteropus giganteus), forms large communal roosts on treetops, often in close proximity to human habitation in sri lanka. this report describes the detection of coronavirus rna in p. medius ...201829498228
mechanism of delayed ovulation in a vespertilionid bat, scotophilus heathi: role of gonadotropin, insulin, and insulin-like growth factor-1. 201929668353
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