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Franco C Sell TK 《Biosecurity and bioterrorism : biodefense strategy, practice, and science》2011,9(2):117-137
Since 2001, the United States government has spent substantial resources on preparing the nation against a bioterrorist attack. Earlier articles in this series have analyzed civilian biodefense funding by the federal government for fiscal years (FY) 2001 through proposed funding for FY2011. This article updates those figures with budgeted amounts for FY2012, specifically analyzing the budgets and allocations for biodefense at the Departments of Health and Human Services, Defense, Homeland Security, Agriculture, Commerce, and State; the Environmental Protection Agency; and the National Science Foundation. This article also includes an updated assessment of the proportion of biodefense funding provided for programs that address multiple scientific, public health, healthcare, national security, and international security issues in addition to biodefense. The FY2012 federal budget for civilian biodefense totals $6.42 billion. Of that total, $5.78 billion (90%) is budgeted for programs that have both biodefense and nonbiodefense goals and applications, and $637.6 million (10%) is budgeted for programs that have objectives solely related to biodefense. 相似文献
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Nasef N Belcastro R Nash A Bishara R Iaboni D Kantores C Tanswell AK Jankov RP 《Free radical research》2011,45(3):359-365
Neonatal lung injury has been induced experimentally by infusion of multivitamin-containing light-exposed parenteral nutrition (PN) solutions. The objective was to explore the role of ascorbate in toxic effects of light-exposed PN on primary cultured foetal rat lung epithelial cells. Hydroperoxides were measured in 3% amino acid solutions at baseline, immediately after addition of either multivitamins or ascorbate alone (400 μg/mL) and again after a 24-h period of exposure to (or protection from) ambient light. Cellular toxicity was assessed by [C(14)]adenine release. Multivitamins or ascorbate alone increased hydroperoxides in PN, which was attenuated by light protection. Light-exposed PN containing multivitamins was more toxic to cells than baseline or light-protected PN. Exposure to ascorbate at concentrations both lower (< 5 μg/mL) and higher (> 1000 μg/mL) than normally contained in PN-induced oxidant-mediated cell death, as indicated by protective effects of hydroperoxide and hydroxyl radical scavengers. This study concludes that ascorbate generates toxic amounts of peroxide in PN solutions. The types and physiological importance of hydroperoxides induced by pro-oxidant effects of ascorbate require further evaluation in vivo. 相似文献
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Insulin-degrading enzyme (IDE) is a thiol sensitive peptidase that degrades insulin and amyloid β, and has been linked to type 2 diabetes mellitus and Alzheimer's disease. We examined the thiol sensitivity of IDE using S-nitrosoglutathione, reduced glutathione, and oxidized glutathione to distinguish the effects of nitric oxide from that of the redox state. The in vitro activity of IDE was studied using either partially purified cytosolic enzyme from male Sprague-Dawley rats, or purified rat recombinant enzyme. We confirm that nitric oxide inhibits the degrading activity of IDE, and that it affects proteasome activity through this interaction with IDE, but does not affect the proteasome directly. Oxidized glutathione inhibits IDE through glutathionylation, which was reversible by dithiothreitol but not by ascorbic acid. Reduced glutathione had no effect on IDE, but reacted with partially degraded insulin to disrupt its disulfide bonds and accelerate its breakdown to trichloroacetic acid soluble fragments. Our results demonstrate the sensitivity of insulin degradation by IDE to the redox environment and suggest another mechanism by which the cell's oxidation state may contribute to the development of, and the link between, type 2 diabetes and Alzheimer's disease. 相似文献
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Sung K Dolcos S Flor-Henry S Zhou C Gasior C Argo J Dolcos F 《Journal of visualized experiments : JoVE》2011,(53):e2379
The ability to gauge social interactions is crucial in the assessment of others' intentions. Factors such as facial expressions and body language affect our decisions in personal and professional life alike (1). These "friend or foe" judgements are often based on first impressions, which in turn may affect our decisions to "approach or avoid". Previous studies investigating the neural correlates of social cognition tended to use static facial stimuli (2). Here, we illustrate an experimental design in which whole-body animated characters were used in conjunction with functional magnetic resonance imaging (fMRI) recordings. Fifteen participants were presented with short movie-clips of guest-host interactions in a business setting, while fMRI data were recorded; at the end of each movie, participants also provided ratings of the host behaviour. This design mimics more closely real-life situations, and hence may contribute to better understanding of the neural mechanisms of social interactions in healthy behaviour, and to gaining insight into possible causes of deficits in social behaviour in such clinical conditions as social anxiety and autism (3). 相似文献
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ek Menglin Wang Jan obotník Simon Hellemans David Sillam-Dusss Nobuaki Mizumoto Petr Stiblík Crystal Clitheroe Tomer Lu Juan Jos Gonzlez Plaza Alma Mohagan Jean-Jacques Rafanomezantsoa Brian Fisher Michael S. Engel Yves Roisin Theodore A. Evans Rudolf Scheffrahn Thomas Bourguignon 《Molecular biology and evolution》2022,39(5)
Termites are major decomposers in terrestrial ecosystems and the second most diverse lineage of social insects. The Kalotermitidae form the second-largest termite family and are distributed across tropical and subtropical ecosystems, where they typically live in small colonies confined to single wood items inhabited by individuals with no foraging abilities. How the Kalotermitidae have acquired their global distribution patterns remains unresolved. Similarly, it is unclear whether foraging is ancestral to Kalotermitidae or was secondarily acquired in a few species. These questions can be addressed in a phylogenetic framework. We inferred time-calibrated phylogenetic trees of Kalotermitidae using mitochondrial genomes of ∼120 species, about 27% of kalotermitid diversity, including representatives of 21 of the 23 kalotermitid genera. Our mitochondrial genome phylogenetic trees were corroborated by phylogenies inferred from nuclear ultraconserved elements derived from a subset of 28 species. We found that extant kalotermitids shared a common ancestor 84 Ma (75–93 Ma 95% highest posterior density), indicating that a few disjunctions among early-diverging kalotermitid lineages may predate Gondwana breakup. However, most of the ∼40 disjunctions among biogeographic realms were dated at <50 Ma, indicating that transoceanic dispersals, and more recently human-mediated dispersals, have been the major drivers of the global distribution of Kalotermitidae. Our phylogeny also revealed that the capacity to forage is often found in early-diverging kalotermitid lineages, implying the ancestors of Kalotermitidae were able to forage among multiple wood pieces. Our phylogenetic estimates provide a platform for critical taxonomic revision and future comparative analyses of Kalotermitidae. 相似文献