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Dangel ET 《Science (New York, N.Y.)》1996,271(5246):129b-130b
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Woods AM McIlmoil CJ Rankin EN Packer AA Stevens JC Macievic JA Brown AB Porter JP Judd AM 《Domestic animal endocrinology》2008,35(2):217-230
The release of adrenal steroids during acute stress is primarily regulated by adrenocorticotropic hormone (ACTH). In contrast, during chronic inflammatory stress additional factors are involved in regulating adrenal function. Leukemia inhibitory factor (LIF) is a pleiotropic cytokine that increases ACTH release from the pituitary. In addition, LIF and LIF receptors (LIFR) are expressed in the human adrenal cortex and the human adrenocortical tumor cell line H295R. Furthermore, LIF increases basal and ACTH-stimulated cortisol release from H295R cells. However, the expression of LIF and LIFR in non-human adrenal glands and the effects of LIF on the release of cortisol from adrenal cells of non-human species have not been determined. Furthermore, the effects of LIF on adrenal androgen release from all species are unknown. In this study, immunohistochemistry, Western blots, RT-PCR, and nucleotide sequencing was utilized to demonstrate that LIF and its receptor are expressed throughout the bovine adrenal cortex. Although LIF did not modify basal cortisol release from dispersed cells isolated from the bovine adrenal zona fasciculate, this cytokine increased ACTH-stimulated release of cortisol from these cells in a manner dependent on the LIF concentration and exposure interval. In contrast, LIF in a concentration-dependent and time-dependent manner decreased basal and ACTH-stimulated adrenal androgen release from dispersed cells isolated from the bovine adrenal zona reticularis. Because LIF release increases during inflammatory stress and this cytokine stimulates adrenal cortisol release and inhibits adrenal androgen release, this cytokine may play an important role in regulating the release of adrenal steroids during inflammatory stress. 相似文献
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Alissa B. Kriss Pierce A. Paul Xiangming Xu Paul Nicholson Fiona M. Doohan Laszlo Hornok Alberto Rietini Simon G. Edwards Laurence V. Madden 《European journal of plant pathology / European Foundation for Plant Pathology》2012,133(4):975-993
Measurements of local environmental conditions, intensity of Fusarium head blight (FHB) in wheat spikes, biomass of Fusarium graminearum, F. culmorum, and F. poae (pathogens causing FHB) and concentration of the mycotoxins deoxynivalenol (DON) and nivalenol (NIV) in harvested wheat grain were obtained in a total of 150 location-years, originating in three European countries (Hungary, Ireland, United Kingdom) from 2001 to 2004. Through window-pane methodology, the length and starting time of temporal windows where the environmental variables were significantly associated with the biological variables were identified. Window lengths of 5 to 30?days were evaluated, with starting times from 18?days before anthesis to harvest. Associations were quantified with nonparametric Spearman correlation coefficients. All biological variables were significantly associated with at least one evaluated environmental variable (P?≤?0.05). Moisture-related variables (e.g., average relative humidity, hours of relative humidity above 80%) had the highest positive correlations with the biological variables, but there also was a significant negative correlation between average temperature and several biological variables. When significant correlations were found, they were generally for all window lengths, but for a limited number of window start times (generally before anthesis for disease index and after anthesis for the toxins and late-season fungal biomasses). Semi-partial Spearman correlation coefficients were used to evaluate the relationship between the environmental variables and the concentration of DON and NIV after the effects of FHB intensity and fungal biomass on the mycotoxins were removed. Significant semi-partial correlations were found between relative humidity variables and DON, and between temperature and relative humidity variables and NIV for time windows that started after anthesis (and not for any earlier time windows). Results confirm that the environment influences disease, fungal biomass, and mycotoxin production, and help refine the time windows where the association is greatest. However, variability in the relationships was high, indicating that no single environmental variable is sufficient for prediction of disease or mycotoxin contamination. 相似文献
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A common approach to land use change analyses in multidisciplinary landscape-level studies is to delineate discrete forest
and non-forest or urban and non-urban land use categories to serve as inputs into sets of integrated sub-models describing
socioeconomic and ecological processes. Such discrete land use categories, however, may be inappropriate when the socioeconomic
and ecological processes under study are sensitive to a range of human habitation. In this paper, we characterize the spatial
dynamic distribution of humans throughout the forest landscape of western Oregon (USA). We develop an empirical model describing
the spatial distribution and rate of change in historic building densities as a function of a gravity index of development
pressure, existing building densities, slope, elevation, and existing land use zoning. We use the empirical model to project
changes in building densities that are applied to a 1995 base map of building density to describe future spatial distributions
of buildings over time. The projected building density maps serve as inputs into a multidisciplinary landscape-level analysis
of socioeconomic and ecological processes in Oregon's Coast Range Mountains.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
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An investigation of the soft coral Asterospicularia laurae collected on the Great Barrier Reef, Australia, afforded the cytotoxic diterpene 13-epi-9-deacetoxyxenicin (1) in addition to the known metabolites 13-epi-9-deacetylxenicin (2) and gorgosterol. 13-Epi-9-deacetoxyxenicin readily underwent an autoxidation reaction in solution to afford a single product, the hydroperoxide 3. Structures, stereochemistry, and NMR assignments were established by high resolution NMR spectroscopy and by comparison with published data for known compounds. 相似文献
6.
Smith DJ Barri A Herges G Hahn J Yersin AG Jourdan A 《Journal of agricultural and food chemistry》2012,60(12):3151-3157
Butyrate is a byproduct of microbial carbohydrate fermentation that occurs primarily in the large intestine. When added to feed, butyrate quickly disappears in the upper digestive tract. Because butyrate is important for epithelial cell development, mucosal integrity, and animal growth, an encapsulation technique has been developed that allows for the slow release of butyrate into the small and large intestines. The purpose of this study was to describe the in vitro release of calcium [1-(14)C]butyrate, formulated into a slow-release (protected) bead, into water and simulated intestinal fluids and to compare the in vivo absorption and disposition of unprotected versus protected calcium [1-(14)C]butyrate in broiler chicks. Formulation of calcium [1-(14)C]butyrate into protected beads allowed release of 5.8 ± 0.2 and 3.4 ± 0.2% of the formulated radiocarbon into water and gastric fluid, respectively, after 2 h of incubation. Beads incubated in gastric fluid for 2 h and subsequently incubated in simulated intestinal fluid released a total of 17.4 ± 0.8% of the formulated radioactivity. Release of respiratory [(14)C]CO(2) after oral dosing of aqueous calcium [1-(14)C]butyrate in broiler chicks peaked at 15.2 ± 5.2% per hour 1.5 h after dosing; in contrast, maximal rates of release in chicks dosed with protected calcium [1-(14)C]butyrate occurred 4 h after dosing at 9.0 ± 3.1% per hour. The data suggested an improved efficacy of protected butyrate delivery to intestinal tissues over nonprotected butyrate. This study confirmed that encapsulation strategies designed to enhance delivery of ingredients to improve intestinal health are effective at prolonging intestinal exposure to butyrate. Encapsulation of such ingredients might benefit the food and feed industries. 相似文献
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MicroRNAs are small RNA molecules that regulate messenger RNA (mRNA) expression. MicroRNA 122 (miR-122) is specifically expressed and highly abundant in the human liver. We show that the sequestration of miR-122 in liver cells results in marked loss of autonomously replicating hepatitis C viral RNAs. A genetic interaction between miR-122 and the 5' noncoding region of the viral genome was revealed by mutational analyses of the predicted microRNA binding site and ectopic expression of miR-122 molecules containing compensatory mutations. Studies with replication-defective RNAs suggested that miR-122 did not detectably affect mRNA translation or RNA stability. Therefore, miR-122 is likely to facilitate replication of the viral RNA, suggesting that miR-122 may present a target for antiviral intervention. 相似文献
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Alissa W. St. Blanc Rebecca A. Csomos 《The Canadian veterinary journal. La revue veterinaire canadienne》2021,62(11):1207
The objectives of this study were to validate the 2.0 mm Endo GIA stapler for lung lobectomies and to compare procedural time and air leakage incidence with suture ligation. Sixteen canine cadavers, 18 to 27 kg, were randomly assigned to undergo lung lobectomy of the right middle lung lobe through intercostal thoracotomy, after which suture ligation or the 2.0 mm Endo GIA stapler was used. Procedural time was recorded. Following the lobectomy, the thoracic cavity was filled with fluid. Positive pressure ventilation was used to hold pressure at 20 cm H2O for 5 minutes. The bronchus was assessed for air leakage as evidenced by visualization of gas bubbles and the ability to maintain positive pressure. Procedural time and air leakage incidence were compared between groups.By these assessments, the 2.0 mm Endo GIA stapler was successful for lung lobectomies in all cadavers. There was no significant difference (t = −0.856, P = 0.407) in body weight by procedure assignment. Procedural time was significantly shorter (P < 0.0001) using the Endo GIA stapler compared to suture ligation. There was no significant correlation (r = 0.044, P = 0.873) between body weight and procedural time. There were no incidents of air leakage in either group. The 2.0 mm Endo GIA stapler may be used as an alternative device for lung lobectomies in canine cadavers. Smaller staples may provide more complete compression of hilar vessels and bronchi, resulting in reduced hemorrhage, air leakage, and thoracic contamination in cases with infection or neoplasia. 相似文献