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191.
Coenzyme A (CoA) is an essential cofactor for all forms of life. The biochemistry underpinning the assembly of CoA in Escherichia coli and other enterobacteria is well understood, except for the events leading to maturation of the L-aspartate-α-decarboxylase (PanD) enzyme that converts pantothenate to β-alanine. PanD is synthesized as pro-PanD, which undergoes an auto-proteolytic cleavage at residue Ser25 to yield the catalytic pyruvoyl moiety of the enzyme. Since 1990, it has been known that E. coli yhhK strains are pantothenate auxotrophs, but the role of YhhK in pantothenate biosynthesis remained an enigma. Here we show that Salmonella enterica yhhK strains are also pantothenate auxotrophs. In vivo and in vitro evidence shows that YhhK interacts directly with PanD, and that such interactions accelerate pro-PanD maturation. We also show that S. enterica yhhK strains accumulate pro-PanD, and that not all pro-PanD proteins require YhhK for maturation. For example, the Corynebacterium glutamicum panD(+) gene corrected the pantothenate auxotrophy of a S. enterica yhhK strain, supporting in vitro evidence obtained by others that some pro-PanD proteins autocleave at faster rates. We propose the name PanM for YhhK to reflect its role as a trigger of pro-PanD maturation by stabilizing pro-PanD in an autocleavage-prone conformation. 相似文献
192.
Kevin D. Shield Gerrit Gmel Tara Kehoe-Chan Deborah A. Dawson Bridget F. Grant Jürgen Rehm 《PloS one》2013,8(1)
Background
Alcohol has been linked to health disparities between races in the US; however, race-specific alcohol-attributable mortality has never been estimated. The objective of this article is to estimate premature mortality attributable to alcohol in the US in 2005, differentiated by race, age and sex for people 15 to 64 years of age.Methods and Findings
Mortality attributable to alcohol was estimated based on alcohol-attributable fractions using indicators of exposure from the National Epidemiologic Survey on Alcohol and Related Conditions and risk relations from the Comparative Risk Assessment study. Consumption data were corrected for undercoverage (the observed underreporting of alcohol consumption when using survey as compared to sales data) using adult per capita consumption from WHO databases. Mortality data by cause of death were obtained from the US Department of Health and Human Services. For people 15 to 64 years of age in the US in 2005, alcohol was responsible for 55,974 deaths (46,461 for men; 9,513 for women) representing 9.0% of all deaths, and 1,288,700 PYLL (1,087,280 for men; 201,420 for women) representing 10.7% of all PYLL. Per 100,000 people, this represents 29 deaths (29 for White; 40 for Black; 82 for Native Americans; 6 for Asian/Pacific Islander) and 670 PYLL (673 for White; 808 for Black; 1,808 for Native American; 158 for Asian/Pacific Islander). Sensitivity analyses showed a lower but still substantial burden without adjusting for undercoverage.Conclusions
The burden of mortality attributable to alcohol in the US is unequal among people of different races and between men and women. Racial differences in alcohol consumption and the resulting harms explain in part the observed disparities in the premature mortality burden between races, suggesting the need for interventions for specific subgroups of the population such as Native Americans. 相似文献193.
Cryptococcus neoformans is a heterothallic basidiomycete with two mating types, MATa and MATalpha. The mating pathway of this fungus has a number of conserved genes, including a MATalpha-specific pheromone (MFalpha1). A modified differential display strategy was used to identify a gene encoding the MATa pheromone. The gene, designated MFa1, is 42 amino acids in length and contains a conserved farnesylation motif. MFa1 is present in three linked copies that span a 20-kb fragment of MATa-specific DNA and maps to the MAT-containing chromosome. Transformation studies showed that MFa1 induced filament formation only in MATalpha cells, demonstrating that MFa1 is functionally conserved. Sequence analysis of the predicted Mfa1 and Mfalpha1 proteins revealed that, in contrast to other fungi such as Saccharomyces cerevisiae, the C. neoformans pheromone genes are structurally and functionally conserved. However, unlike the MFalpha1 gene, which is found in MATalpha strains of both varieties of C. neoformans, MFa1 is specific for the neoformans variety of C. neoformans. 相似文献
194.
Tompson SW Bacino CA Safina NP Bober MB Proud VK Funari T Wangler MF Nevarez L Ala-Kokko L Wilcox WR Eyre DR Krakow D Cohn DH 《American journal of human genetics》2010,87(5):708-712
Fibrochondrogenesis is a severe, autosomal-recessive, short-limbed skeletal dysplasia. In a single case of fibrochondrogenesis, whole-genome SNP genotyping identified unknown ancestral consanguinity by detecting three autozygous regions. Because of the predominantly skeletal nature of the phenotype, the 389 genes localized to the autozygous intervals were prioritized for mutation analysis by correlation of their expression with known cartilage-selective genes via the UCLA Gene Expression Tool, UGET. The gene encoding the α1 chain of type XI collagen (COL11A1) was the only cartilage-selective gene among the three candidate intervals. Sequence analysis of COL11A1 in two genetically independent fibrochondrogenesis cases demonstrated that each was a compound heterozygote for a loss-of-function mutation on one allele and a mutation predicting substitution for a conserved triple-helical glycine residue on the other. The parents who were carriers of missense mutations had myopia. Early-onset hearing loss was noted in both parents who carried a loss-of-function allele, suggesting COL11A1 as a locus for mild, dominantly inherited hearing loss. These findings identify COL11A1 as a locus for fibrochondrogenesis and indicate that there might be phenotypic manifestations among carriers. 相似文献
195.
Priority threat management of invasive animals to protect biodiversity under climate change 下载免费PDF全文
Jennifer Firn Ramona Maggini Iadine Chadès Sam Nicol Belinda Walters Andy Reeson Tara G. Martin Hugh P. Possingham Jean‐Baptiste Pichancourt Rocio Ponce‐Reyes Josie Carwardine 《Global Change Biology》2015,21(11):3917-3930
Climate change is a major threat to global biodiversity, and its impacts can act synergistically to heighten the severity of other threats. Most research on projecting species range shifts under climate change has not been translated to informing priority management strategies on the ground. We develop a prioritization framework to assess strategies for managing threats to biodiversity under climate change and apply it to the management of invasive animal species across one‐sixth of the Australian continent, the Lake Eyre Basin. We collected information from key stakeholders and experts on the impacts of invasive animals on 148 of the region's most threatened species and 11 potential strategies. Assisted by models of current distributions of threatened species and their projected distributions, experts estimated the cost, feasibility, and potential benefits of each strategy for improving the persistence of threatened species with and without climate change. We discover that the relative cost‐effectiveness of invasive animal control strategies is robust to climate change, with the management of feral pigs being the highest priority for conserving threatened species overall. Complementary sets of strategies to protect as many threatened species as possible under limited budgets change when climate change is considered, with additional strategies required to avoid impending extinctions from the region. Overall, we find that the ranking of strategies by cost‐effectiveness was relatively unaffected by including climate change into decision‐making, even though the benefits of the strategies were lower. Future climate conditions and impacts on range shifts become most important to consider when designing comprehensive management plans for the control of invasive animals under limited budgets to maximize the number of threatened species that can be protected. 相似文献
196.
Soil and greenhouse gas responses to biochar additions in a temperate hardwood forest 总被引:2,自引:0,他引:2
Tara E. Sackett Nathan Basiliko Genevieve L. Noyce Carolyn Winsborough Jonathan Schurman Chihiro Ikeda Sean C. Thomas 《Global Change Biology Bioenergy》2015,7(5):1062-1074
Biochar additions can improve soil fertility and sequester carbon, but biochar effects have been investigated primarily in agricultural systems. Biochar from spruce and maple sawdust feedstocks (with and without inorganic phosphorus in a factorial design) were added to plots in a commercially managed temperate hardwood forest stand in central Ontario, Canada; treatments were applied as a top‐dressing immediately prior to fall leaf abscission in September 2011. Forests in this region have acidic, sandy soils, and due to nitrogen deposition may exhibit phosphorus, calcium, and magnesium limitation. To investigate short‐term impacts of biochar application on soil nutrient supply and greenhouse gas fluxes as compared to phosphorus fertilization, data were collected over the first year after treatment application; linear mixed models were used to analyze data. Two to six weeks after treatment application, there were higher concentrations of potassium in spruce and maple biochar plots, and phosphorus in spruce biochar plots, as compared to the control treatment. There were higher concentrations of calcium, magnesium, and phosphorus in the phosphorus plots. In the following spring and summer (9–12 months after treatment application), there were higher soil calcium concentrations in maple biochar plots, and phosphorus plots still had higher soil phosphorus concentrations than control plots. No treatment effects on fluxes of carbon dioxide, methane, or nitrous oxide were detected in the field; however, laboratory incubations after 12 months showed higher microbial respiration in soils from maple biochar plots as compared to spruce biochar, despite no effect on microbial biomass. The results suggest that the most important short‐term impact of biochar additions in this system is the increased supply of the limiting plant nutrients phosphorus and calcium. We expect that larger changes in mineral soil physical and chemical properties will occur when the surface‐applied biochar becomes incorporated into the soil after a few years. 相似文献
197.
Tara?Clinton-McHarg Sze?Lin?Yoong Flora?Tzelepis Tim?Regan Alison?Fielding Eliza?Skelton Melanie?Kingsland Jia?Ying?Ooi Luke?WolfendenEmail author 《Implementation science : IS》2015,11(1):148
Background
Recent reviews have synthesised the psychometric properties of measures developed to examine implementation science constructs in healthcare and mental health settings. However, no reviews have focussed primarily on the properties of measures developed to assess innovations in public health and community settings. This review identified quantitative measures developed in public health and community settings, examined their psychometric properties, and described how the domains of each measure align with the five domains and 37 constructs of the Consolidated Framework for Implementation Research (CFIR).Methods
MEDLINE, PsycINFO, EMBASE, and CINAHL were searched to identify publications describing the development of measures to assess implementation science constructs in public health and community settings. The psychometric properties of each measure were assessed against recommended criteria for validity (face/content, construct, criterion), reliability (internal consistency, test-retest), responsiveness, acceptability, feasibility, and revalidation and cross-cultural adaptation. Relevant domains were mapped against implementation constructs defined by the CFIR.Results
Fifty-one measures met the inclusion criteria. The majority of these were developed in schools, universities, or colleges and other workplaces or organisations. Overall, most measures did not adequately assess or report psychometric properties. Forty-six percent of measures using exploratory factor analysis reported >50 % of variance was explained by the final model; none of the measures assessed using confirmatory factor analysis reported root mean square error of approximation (<0.06) or comparative fit index (>0.95). Fifty percent of measures reported Cronbach’s alpha of <0.70 for at least one domain; 6 % adequately assessed test-retest reliability; 16 % of measures adequately assessed criterion validity (i.e. known-groups); 2 % adequately assessed convergent validity (r?>?0.40). Twenty-five percent of measures reported revalidation or cross-cultural validation. The CFIR constructs most frequently assessed by the included measures were relative advantage, available resources, knowledge and beliefs, complexity, implementation climate, and other personal resources (assessed by more than ten measures). Five CFIR constructs were not addressed by any measure.Conclusions
This review highlights gaps in the range of implementation constructs that are assessed by existing measures developed for use in public health and community settings. Moreover, measures with robust psychometric properties are lacking. Without rigorous tools, the factors associated with the successful implementation of innovations in these settings will remain unknown198.
Tagmyer TL Craigo JK Cook SJ Even DL Issel CJ Montelaro RC 《Journal of virology》2008,82(8):4052-4063
A highly effective attenuated equine infectious anemia virus (EIAV) vaccine (EIAV(D9)) capable of protecting 100% of horses from disease induced by a homologous Env challenge strain (EIAV(PV)) was recently tested in ponies to determine the level of protection against divergent Env challenge strains (J. K. Craigo, B. S. Zhang, S. Barnes, T. L. Tagmyer, S. J. Cook, C. J. Issel, and R. C. Montelaro, Proc. Natl. Acad. Sci. USA 104:15105-15110, 2007). An inverse correlation between challenge strain Env variation and vaccine protection from disease was observed. Given the striking differences in protective immunity, we hypothesized that analysis of the humoral and cellular immune responses to the Env protein could reveal potential determinants of vaccine protection. Neutralization activity against the homologous Env or challenge strain-specific Env in immune sera from the vaccinated ponies did not correlate with protection from disease. Cellular analysis with Env peptide pools did not reveal an association with vaccine protection from disease. However, when individual vaccine-specific Env peptides were utilized, eight cytotoxic-T-lymphocyte (CTL) peptides were found to associate closely with vaccine protection. One of these peptides also yielded the only lymphoproliferative response associated with protective immunity. The identified peptides spanned both variable and conserved regions of gp90. Amino acid divergence within the principal neutralization domain and the identified peptides profoundly affected immune recognition, as illustrated by the inability to detect cross-reactive neutralizing antibodies and the observation that certain peptide-specific CTL responses were altered. In addition to identifying potential Env determinants of EIAV vaccine efficacy and demonstrating the profound effects of defined Env variation on immune recognition, these data also illustrate the sensitivity offered by individual peptides compared to peptide pools in measuring cellular immune responses in lentiviral vaccine trials. 相似文献
199.
200.
Tara Kiran Alexander Kopp Rahim Moineddin J. Charles Victor Robert J. Campbell Baiju R. Shah Richard H. Glazier 《CMAJ》2013,185(3):E167-E173