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Burkitt JM Haskins SC Nelson RW Kass PH 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2007,21(2):226-231
BACKGROUND: A syndrome of relative adrenal insufficiency has been identified in septic humans, and is associated with hypotension and death. Relative adrenal insufficiency is generally associated with basal serum cortisol concentration within or above the reference range and a blunted cortisol response to adrenocorticotropic hormone administration. It is unknown whether relative adrenal insufficiency occurs in septic dogs. HYPOTHESIS: That relative adrenal insufficiency occurs in septic dogs, and that relative adrenal insufficiency is associated with hypotension and mortality. ANIMALS: Thirty-three septic dogs admitted to a small animal intensive care unit. METHODS: Dogs were included in the study if they had a known or suspected infectious disease and had systemic inflammatory response syndrome. Dogs were excluded if they had disease or medication history expected to affect the hypothalamic-pituitary-adrenal axis. Serum cortisol and endogenous plasma adrenocorticotropic hormone concentrations were measured before, and serum cortisol concentration measured 1 hour after, intramuscular administration of 250 microg of cosyntropin/dog. The change in cortisol concentration (delta-cortisol) before and after cosyntropin administration was determined in each dog. RESULTS: Hypotension was associated with lower delta-cortisol values (OR 1.3; CI 1.0-1.9; P = .029). delta-Cortisol cutoff of 3.0 microg/dL was most accurate for predicting hypotension, survival to discharge, and 28-day survival. The rate of death in dogs with delta-cortisol < or = 3 microg/dL was 4.1 times that of dogs with delta-cortisol > 3 microg/dL (RR 4.1; CI 1.5-12.3; P = .01). CONCLUSIONS AND CLINICAL RELEVANCE: Delta-cortisol < or = 3 microg/dL after adrenocorticotropic hormone administration is associated with systemic hypotension and decreased survival in septic dogs. 相似文献
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Microbial activities impact arsenic (As) transformation in mine tailings substantially,yet little is understood on the functional diversity of As metabolism genes.This study explored this issue using a metagenomic approach coupled by a local BLASTN procedure established in our recent studies.An assembled metagenome,recovered from hypersaline and sulfidic mine tailings,was screened for As metabolism genes aioA,arrA,arsC and arsM.This was done using a local BLASTN procedure against databases of the As metabolism genes built in this study.Putative As metabolism genes detected in the assembled metagenome included 11 arsM,20 arsC and 1 arrA full-length sequences.Together with the rRNA-based phylogenetic profiling results,a picture depicting microbial As cycling in the tailings to the genus level was obtained.It was found that most of the dominant genera in the tailings potentially harboured the genes for As reduction and/or methylation.In particular,a typical pyrite-eater present in the tailings,Thioalkalivibrio sp.,was found to harbour not only arsC and arsM,but also arrA.These results highlight the unexpected diversity of As metabolism genes in the tailings,especially considering the extremely low species diversity therein.The microbial As cycling picture established here has potential use for guiding the purposeful manipulation of As biogeochemistry in the tailings. 相似文献
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Regional economic resilience can be defined as an economy’s ability to withstand and recover quickly from shocks. The ability to measure resilience is necessary to developing our understanding of what influences resilience. In this paper, we develop a new, two‐dimensional quantitative measure of resilience using observed differences between expected and actual employment in a region following a shock and distinguish the response to the shock from random variation. We demonstrate one application of this metric to US county‐level employment data to compare county responses to the 2007–2009 national recession and discuss how different regions of the United States responded to the shock of the Great Recession in terms of resilience. 相似文献