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81.
Meyerhoff RR Nighot PK Ali RA Blikslager AT Koci MD 《Comparative immunology, microbiology and infectious diseases》2012,35(1):63-69
The inducible nitric oxide synthase (iNOS) enzyme has long been recognized as a key mediator of innate immune responses to infectious diseases across the phyla. Its role in killing or inactivating bacterial, parasitic, and viral pathogens has been documented in numerous host systems. iNOS, and its innate immune mediator NO has also been described to have negative consequence on host tissues as well; therefore understanding the pathogenesis of any infectious agent which induces iNOS expression requires a better understanding of the role iNOS and NO play in that disease. Previous studies in our laboratory and others have demonstrated evidence for increased levels of iNOS and activity of its innate immune mediator NO in the intestine of turkeys infected with astrovirus. To begin to characterize the role iNOS plays in the innate immune response to astrovirus infection, we identified, characterized, developed tkiNOS specific reagents, and demonstrated that the intestinal epithelial cells induce expression of iNOS following astrovirus infection. These data are the first to our knowledge to describe the tkiNOS gene, and demonstrate that astrovirus infection induces intestinal epithelial cells to express iNOS, suggesting these cells play a key role in the antiviral response to enteric infections. 相似文献
82.
Background
Expression levels for genes of interest must be normalized with an appropriate reference, or housekeeping gene, to make accurate comparisons of quantitative real-time PCR results. The purpose of this study was to identify the most stable housekeeping genes in porcine articular cartilage subjected to a mechanical injury from a panel of 10 candidate genes.Results
Ten candidate housekeeping genes were evaluated in three different treatment groups of mechanically impacted porcine articular cartilage. The genes evaluated were: beta actin, beta-2-microglobulin, glyceraldehyde-3-phosphate dehydrogenase, hydroxymethylbilane synthase, hypoxanthine phosphoribosyl transferase, peptidylprolyl isomerase A (cyclophilin A), ribosomal protein L4, succinate dehydrogenase flavoprotein subunit A, TATA box binding protein, and tyrosine 3-monooxygenase/tryptophan 5-monooxygenase activation protein—zeta polypeptide. The stability of the genes was measured using geNorm, BestKeeper, and NormFinder software. The four most stable genes measured via geNorm were (most to least stable) succinate dehydrogenase flavoprotein, subunit A, peptidylprolyl isomerase A, glyceraldehyde-3-phosphate dehydrogenase, beta actin; the four most stable genes measured via BestKeeper were glyceraldehyde-3-phosphate dehydrogenase, peptidylprolyl isomerase A, beta actin, succinate dehydrogenase flavoprotein, subunit A; and the four most stable genes measured via NormFinder were peptidylprolyl isomerase A, succinate dehydrogenase flavoprotein, subunit A, glyceraldehyde-3-phosphate dehydrogenase, beta actin.Conclusions
BestKeeper, geNorm, and NormFinder all generated similar results for the most stable genes in porcine articular cartilage. The use of these appropriate reference genes will facilitate accurate gene expression studies of porcine articular cartilage and suggest appropriate housekeeping genes for articular cartilage studies in other species. 相似文献83.
McCally RE Kim SE Bacon NJ Winter MD Cords AA Conway JA 《Journal of the American Animal Hospital Association》2012,48(3):198-202
A 2 yr old dog presented for dysphagia and coughing secondary to a 4 cm × 4 cm turgid subepiglottic mass. Cervical radiographs, an esophagram, and computed tomography confirmed the presence of a cystic mass that was not intimately associated with any surrounding structures. An incisional biopsy confirmed the cystic nature of the mass and helped to rule out a malignancy. A marginal surgical excision was performed via a ventral approach. Histopathology of the mass was consistent with a thyroglossal duct cyst. This is the first report of a thyroglossal duct cyst in this location in a dog. There was no recurrence of clinical signs 14 mo after surgery. 相似文献
84.
Samuel D. Fuhlendorf David M. Engle R. Dwayne Elmore Ryan F. Limb Terrence G. Bidwell 《Strength and Conditioning Journal》2012,65(6):579-589
This article examines the question of how well the rangeland management profession has served conservation of patterns and processes that support multiple ecosystem services. We examine the paradigms under which rangeland management operates and argue that our profession developed under the utilitarian paradigm with the primary goals of sustainable forage for livestock production. While optimization of multiple rangeland products and services has always been a consideration, a comprehensive set of principles have not be been developed to advance this concept. We argue that fire and grazing, often viewed as mere tools used for production goals, should rather be viewed as essential ecosystem processes. Rangeland management continues to operate under the utilitarian paradigm appropriate to societal values of the 20th century and by and large has failed to provide management guidance to reverse degradation of several highly valued ecosystem services. We support this argument with evidence that biodiversity has declined on rangelands in the past half century and that much of this decline is due to management goals that favor a narrow suite of species. The full suite of ecosystem services valued by society will only benefit by management for heterogeneity, which implies that there is no one goal for management and that landscape-level planning is crucial. Explicitly incorporating heterogeneity into state-and-transition models is an important advancement not yet achieved by our profession. We present new principles for rangeland management formed on the basis of conservation of pattern and process. While recognizing that many rangelands have significant deviations from historic plant communities and disturbance regimes, we suggest that management for conservation of pattern and process should focus on fire and grazing to the extent possible to promote a shifting mosaic across large landscapes that include patches that are highly variable in the amount of disturbance rather than the current goal of uniform moderate disturbance. 相似文献
85.
86.
87.
We conducted a mark-recapture study of three subpopulations of Craugastor punctariolus at a mid-elevation site in central Panama between 1999 and 2005. The study spans a period over which the pathogenic fungus Batrachochytrium dendrobatidis (Bd) was absent from the site, invaded the site and decimated all amphibian populations, and now persists. We quantified natural demographic parameters prior to and during an event of mass mortality due to chytridiomycosis caused by Bd. Prior to the event of mass mortality, all three subpopulations of C. punctariolus were large (19-68 animals/200 m), showed a stable age-size distribution, and had high survival. All age-size classes of this species co-occurred on boulder clumps along streams, and adults showed high site fidelity and were likely territorial. Following detection of Bd at this site in late September 2004, four dead C. punctariolus were found infected with Bd and all three subpopulations completely disappeared from this site within 2 months. The association of all age-size classes with microhabitats appropriate for survival and growth of Bd likely contributed to the rapid and severe degree of decline of this species at this site. These data provide insight into the patterns and mechanisms of decline within a species due to Bd. 相似文献
88.
This case report describes tuberculosis (TB) due to infection with Mycobacterium bovis (M. bovis) in alpaca (Lama pacos) on a farm in Ireland. Two severely debilitated alpaca were presented to the University Veterinary Hospital, University College Dublin in November 2004. Bloods were taken, and haematology and biochemistry results were indicative of chronic infection. Radiological examination showed evidence of diffuse granulomatous pneumonia suggestive of tuberculosis. On necropsy there were granulomatous lesions present throughout many body organs including lung, liver, kidney, intestine as well on peritoneum and mesentery. Culture of acid-fast bacilli from lesions led to a diagnosis of tuberculosis due to M. bovis. The use of intradermal skin testing proved inefficient and unreliable for ante mortem diagnosis of tuberculosis in alpaca. Infection due to M. bovis should be considered among the differential diagnoses of debilitating diseases in alpaca, particularly those farmed in areas known to be traditional black spots for tuberculosis in cattle. 相似文献
89.
90.
Yoshikawa H Nakamoto Y Ozawa T Dickinson RM 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2008,70(8):825-828
A 9-year-old male Shih Tzu with osteosarcoma had a forelimb amputation and underwent chemotherapy. During chemotherapy, the right eye was enucleated due to refractory glaucoma, and was diagnosed as anterior uveal malignant melanoma. The dog lived for 4 months after the enucleation without treatment. After the dog died, the mass in the eye was re-evaluated immunohistochemically, and it was diagnosed as metastasis of appendicular osteosarcoma. Metastasis of appendicular osteosarcoma to the anterior chamber is quite rare, and the clinical course which showed clinically detectable metastases to the eye before systemic multi-organ metastases was quite unique. 相似文献