VITAMIN A AND THE THYROID     

Sheets RF  Struck HC 《Science (New York, N.Y.)》1942,96(2496):408-409

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Response to Goodwin et al.     

MK Wun  R Malik 《Australian veterinary journal》2023,101(10):413-416

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Comparative Expression Analysis of Gametogenesis‐Associated Genes in Foetal and Adult Bubaline (Bubalus bubalis) Ovaries and Testes          下载免费PDF全文

SM Shah  N Saini  S Ashraf  M Zandi  MK Singh  RS Manik  SK Singla  P Palta  MS Chauhan 《Reproduction in domestic animals》2015,50(3):365-377

This study was conducted to identify and analyse the expression of gametogenesis‐associated genes and proteins in foetal and adult buffalo gonads of both the sexes. Relative quantification of the genes was determined by qPCR and Western blotting. Immunohistochemistry was also performed for various gametogenesis‐associated proteins in foetal and adult gonads of both the sexes. We observed significantly (p < 0.05) increased expression of primordial germ cell‐specific, meiotic as well as genes associated with oocyte maturation and development in foetal ovaries as compared to the adult ones. However, significantly (p < 0.05) increased expression of proteins associated with oocyte maturation like GDF9 and ZP4 was found in adult ovaries, indicating temporal regulation of mRNA translation during oogenesis. Meiotic genes showed significantly (p < 0.05) increased expression in adult testes as compared to foetal testes and ovaries, indicating onset of meiosis at a later stage in spermatogenesis. In general, the expression of primordial germ cell‐associated as well as meiotic genes was higher in adult testes, indicating the increased biological activity in the organ. Immunohistochemistry revealed localized expression of gametogenesis‐associated proteins in ovarian follicles and seminiferous tubules of testes, while the surrounding somatic tissues were devoid of these proteins. The study gives an understanding of the sequential and temporal events of gene expression as well as mRNA translation during male and female gametogenesis. It could also be concluded that follicles and seminiferous tubules are the functional units of the female and male gonads, respectively, and their function could be enhanced by appropriate chemical and genetic intervention of the somatic tissue immediately surrounding them. This assumes importance in the context that buffalo attains sexual maturity at an older age of 2–3 years and have smaller ovaries with lesser number of primordial follicles in comparison with cattle, which is suggested to be the main reason of their poor breeding performance.  相似文献   

Prehistoric agriculture in tropical highlands     

Linares OF  Sheets PD  Rosenthal EJ 《Science (New York, N.Y.)》1975,187(4172):137-145

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Oxygen Concentration and Cysteamine Supplementation During In vitro Production of Buffalo (Bubalus bubalis) Embryos Affect mRNA Expression of BCL‐2, BCL‐XL,MCL‐1, BAX and BID     

G Elamaran  KP Singh  MK Singh  SK Singla  MS Chauhan  RS Manik  P Palta 《Reproduction in domestic animals》2012,47(6):1027-1036

This study examined the effects of O₂ concentration (5% vs 20%) during in vitro maturation (IVM), fertilization (IVF) and culture (IVC) or supplementation of IVM and IVC media with cysteamine (50 and 100 μm , respectively; IVM, IVF and IVC carried out in 20% O₂), on blastocyst rate and relative mRNA abundance of some apoptosis‐related genes measured by real‐time qPCR in immature and in vitro‐matured buffalo oocytes and in embryos at 2‐, 4‐, 8‐ to 16‐cell, morula and blastocyst stages. The blastocyst rate was significantly higher (p < 0.05) while the percentage of TUNEL‐positive cells was significantly lower (p < 0.05) under 5% O₂ than that under 20% O₂. The mRNA expression of anti‐apoptotic genes BCL‐2 and MCL‐1 was significantly higher (p < 0.05) and that of pro‐apoptotic genes BAX and BID was lower (p < 0.05) under 5% O₂ than that under 20% O₂ concentration at many embryonic stages. Following cysteamine supplementation, the blastocyst rate and the relative mRNA abundance of BCL‐XL and MCL‐1 was significantly higher (p < 0.05) and that of BAX but not BID was lower (p < 0.05) at many stages of embryonic development, although it did not affect the percentage of TUNEL positive cells in the blastocysts significantly. The mRNA expression pattern of these genes during embryonic development was different in 5% vs 20% O₂ groups and in cysteamine supplemented vs controls. At the 8‐ to 16‐cell stage, where developmental block occurs in buffalo, the relative mRNA abundance of BCL‐2 and MCL‐1 was highest under 5% O₂ concentration and that of BAX and BID was highest (p < 0.05) under 20% O₂ concentration. These results suggest that one of the mechanisms through which beneficial effects of low O₂ concentration and cysteamine supplementation are mediated during in vitro embryo production is through an increase in the expression of anti‐apoptotic and a decrease in the expression of pro‐apoptotic genes.  相似文献   

Persistence and movement of BHC in a watershed, Mount Mitchell State Park, North Carolina--1967-72     

M D Jackson  T J Sheets  C L Moffett 《Pesticides monitoring journal》1974,8(3):202-208

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Expression and localization of angiopoietin family in corpus luteum during different stages of oestrous cycle and modulatory role of angiopoietins on steroidogenesis,angiogenesis and survivability of cultured buffalo luteal cells          下载免费PDF全文

SR Mishra  MS Parmar  VP Yadav  R Reshma  J Bharati  MK Bharti  A Paul  VS Chouhan  G Taru Sharma  G Singh  M Sarkar 《Reproduction in domestic animals》2016,51(6):855-869

The objective of this study was to document the expression and localization of angiopoietin (ANGPT) family members comprising of angiopoietin (ANGPT1 and ANGPT2), and their receptors (Tie1 and Tie2) in buffalo corpus luteum (CL) obtained from different stages of the oestrous cycle, and the modulatory role of ANGPT1 and ANGPT2 alone or in combinations on progesterone (P₄) secretion and mRNA expression of phosphotidylinositide‐3kinase‐protein kinase B (PI3K‐AKT), phosphoinositide‐dependent kinase (PDK), protein kinase B (AKT), Bcl2 associated death promoter (BAD), caspase 3 and von willebrand factor (vWF) in luteal cells obtained from midluteal phase (MLP) of oestrous cycle in buffalo. Real‐time RT‐PCR (qPCR), Western blot and immunohistochemistry were applied to investigate mRNA expression, protein expression and localization of examined factors whereas, the P₄ secretion was assessed by RIA. The mRNA and protein expression of ANGPT1 and Tie2 was maximum (p < .05) in mid luteal phase (MLP) of oestrous cycle. The ANGPT2 mRNA and protein expression was maximum (p < .05) in early luteal phase, decreased in MLP and again increased in late luteal phase of oestrous cycle. ANGPT family members were localized in luteal cells and endothelial cells with a stage specific immunoreactivity. P₄ secretion was highest (p < .05) with 100 ng/ml at 72 hr when luteal cells were treated with either protein alone. The mRNA expression of PDK, AKT and vWF was highest (p < .05) and BAD along with caspase 3 were lowest (p < .05) at 100 ng/ml at 72 hr of incubation period, when cultured luteal cells were treated with either protein alone or in combination. To conclude, our study explores the steroidogenic potential of angiopoietins to promote P₄ secretion, luteal cell survival and angiogenesis through an autocrine and paracrine actions in buffalo CL.  相似文献   

Alternate Pathway of Infection with Hepatozoon americanum and the Epidemiologic Importance of Predation     

E.M. Johnson  R.J. Panciera  K.E. Allen  M.E. Sheets  J.D. Beal  S.A. Ewing  S.E. Little 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2009,23(6):1315-1318

Background: The range of American canine hepatozoonosis (ACH) is expanding from the southern USA northward. Transmission of Hepatozoon americanum occurs by ingestion of infected Gulf Coast ticks, Amblyomma maculatum. The source of the protozoan for the tick remains undetermined; infected dogs are unusual hosts for the tick. Objective: Compare possible sources of infection by field investigations of 2 multiple‐dog outbreaks of ACH. Animals: Twenty‐eight privately owned dogs (Canis familiaris), 1 coyote (Canis latrans), 31 wild‐trapped cotton rats (Sigmodon hispidus), 24 wild‐trapped field mice (Peromyscus leucopus), and 9 wild‐caught rabbits (Sylvilagus spp.) from sites in eastern Oklahoma were monitored for hepatozoonosis. Six laboratory‐raised cotton rats (S. hispidus), 6 Sprague‐Dawley rats (Rattus norvegicus), 6 C57BL/6J‐Lystbg‐J/J mice (Mus musculus), 6 outbred white mice (M. musculus), 6 New Zealand white rabbits (Oryctolagus cuniculus), and 2 dogs were acquired through commercial vendors for experimental transmission trials of H. americanum. Methods: Four of 15 dogs in a rural neighborhood and 5/12 hunting Beagles were confirmed to be infected by blood smear examination, muscle biopsy, and polymerase chain reaction assay of the 18S rRNA gene of Hepatozoon species. Histories and tick host preferences led to field collections of common prey of canids and experimental transmission trials of H. americanum to selected prey (M. musculus, S. hispidus, R. norvegicus, and O. cuniculus). Results: Dogs with ready access to prey (4/15 dogs) or that were fed prey retrieved from hunts (5/12 hunting Beagles) became infected, providing evidence that predation is an important epidemiologic component of ACH infection. Experimental transmission studies identified a quiescent, infectious stage (cystozoite) of the parasite that provides an alternate mode of transmission to canids through predation, demonstrating that cotton rats, mice, and rabbits but not brown rats may act as paratenic hosts of H. americanum. Conclusions and Clinical Importance: Predation of prey harboring infected A. maculatum or containing cystozoites of H. americanum in their tissues provide 2 modes of transmission of ACH to dogs, putting unconfined dogs at increased risk of infection in endemic areas.  相似文献   

Effects of Activin A on the In Vitro Development and mRNA Expression of Bovine Embryos Cultured in Chemically‐Defined Two‐Step Culture Medium     

JE Park  HJ Oh  SG Hong  G Jang  MK Kim  BC Lee 《Reproduction in domestic animals》2010,45(4):585-593

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Accuracy of selected neurological clinical tests in diagnosing MRI-detectable forebrain lesion in dogs     

MK Chan  P Jull 《Australian veterinary journal》2020,98(10):499-503

This retrospective case study aims to evaluate the accuracy of menace response, response to nasal stimulation and proprioceptive placing in diagnosing forebrain lesion in dogs. A total of 145 client-owned dogs investigated by magnetic resonance imaging study of the brain between December 2017 and June 2019 were evaluated. Seventy-one dogs with no magnetic resonance imaging-detectable intracranial and significant cerebrospinal fluid abnormality or recent history of seizure (<48 h) served as controls. Binary regression analysis was performed to determine the sensitivity, specificity and likelihood ratios of each selected test. Older age at presentation was a significant risk factor for the presence of a forebrain lesion. Menace (62.5%) and proprioceptive deficits (40.5%) were common findings in all dogs. They were also significantly associated with the presence of forebrain abnormality. Moreover, they were more sensitive (77.3% and 82.2%, respectively) and specific (50.0% and 62.5%, respectively) when applied to dogs aged 6 years or older. Nonetheless, all of these tests' likelihood ratios, and thus reliability are poor. These neurological tests are commonly employed for diagnosing forebrain disease in dogs, yet are not highly accurate in diagnosing forebrain abnormality. Clinicians should interpret these clinical test results along with the patient history when designing a diagnostic plan.  相似文献