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991.
Rachel Brower-Sinning Diana Zhong Misty Good Brian Firek Robyn Baker Chhinder P. Sodhi David J. Hackam Michael J. Morowitz 《PloS one》2014,9(9)
Background
Previous studies of infant fecal samples have failed to clarify the role of gut bacteria in the pathogenesis of NEC. We sought to characterize bacterial communities within intestinal tissue resected from infants with and without NEC.Methods
26 intestinal samples were resected from 19 infants, including 16 NEC samples and 10 non-NEC samples. Bacterial 16S rRNA gene sequences were amplified and sequenced. Analysis allowed for taxonomic identification, and quantitative PCR was used to quantify the bacterial load within samples.Results
NEC samples generally contained an increased total burden of bacteria. NEC and non-NEC sample sets were both marked by high inter-individual variability and an abundance of opportunistic pathogens. There was no statistically significant distinction between the composition of NEC and non-NEC microbial communities. K-means clustering enabled us to identify several stable clusters, including clusters of NEC and midgut volvulus samples enriched with Clostridium and Bacteroides. Another cluster containing both NEC and non-NEC samples was marked by an abundance of Enterobacteriaceae and decreased diversity among NEC samples.Conclusions
The results indicate that NEC is a disease without a uniform pattern of microbial colonization, but that NEC is associated with an abundance of strict anaerobes and a decrease in community diversity. 相似文献992.
993.
994.
Michael Weston Michael Fendley Robyn Jewell Mary Satchell Chris Tzaros 《Ecological Management & Restoration》2003,4(3):205-211
Summary Volunteers play an important role in recovery efforts on threatened Australian birds. We surveyed the demography, motivation and preferences of people registered with the Threatened Bird Network, a network dedicated to placing volunteers in recovery efforts. Most were employed or studying and were members of conservation or natural history groups. The main reason for volunteering was an interest in conservation, and most volunteers considered habitat conservation of primary importance. They preferred outdoor projects on highly threatened species and where organizers set clear goals, provided feedback and supervised in a friendly and helpful manner. We also surveyed the recovery projects to determine the extent of volunteer involvement required, and the expectations recovery teams had of volunteers. Volunteers made a major contribution to recovery efforts, with $3.4 million being directed to 32 recovery efforts in the period 1996−2000 − a contribution that has been increasing in recent years. Most activities involved surveying and searching and most activities were available in spring, which coincides with the breeding season of the taxa involved. Volunteers travelled considerable distances, yet only a few projects provided financial support. 相似文献
995.
Lystra P. Hayden Brian D. Hobbs Robyn T. Cohen Robert A. Wise William Checkley James D. Crapo Craig P. Hersh 《Respiratory research》2015,16(1)
Background
Development of adult respiratory disease is influenced by events in childhood. The impact of childhood pneumonia on chronic obstructive pulmonary disease (COPD) is not well defined. We hypothesize that childhood pneumonia is a risk factor for reduced lung function and COPD in adult smokers.Methods
COPD cases and control smokers between 45–80 years old from the United States COPDGene Study were included. Childhood pneumonia was defined by self-report of pneumonia at <16 years. Subjects with lung disease other than COPD or asthma were excluded. Smokers with and without childhood pneumonia were compared on measures of respiratory disease, lung function, and quantitative analysis of chest CT scans.Results
Of 10,192 adult smokers, 854 (8.4 %) reported pneumonia in childhood. Childhood pneumonia was associated with COPD (OR 1.40; 95 % CI 1.17-1.66), chronic bronchitis, increased COPD exacerbations, and lower lung function: post-bronchodilator FEV1 (69.1 vs. 77.1 % predicted), FVC (82.7 vs. 87.4 % predicted), FEV1/FVC ratio (0.63 vs. 0.67; p < 0.001 for all comparisons). Childhood pneumonia was associated with increased airway wall thickness on CT, without significant difference in emphysema. Having both pneumonia and asthma in childhood further increased the risk of developing COPD (OR 1.85; 95 % CI 1.10-3.18).Conclusions
Children with pneumonia are at increased risk for future smoking-related lung disease including COPD and decreased lung function. This association is supported by airway changes on chest CT scans. Childhood pneumonia may be an important factor in the early origins of COPD, and the combination of pneumonia and asthma in childhood may pose the greatest risk.Clinical trials registration
ClinicalTrials.gov, (Active since January 28, 2008). NCT00608764Electronic supplementary material
The online version of this article (doi:10.1186/s12931-015-0273-8) contains supplementary material, which is available to authorized users. 相似文献996.
997.
998.
Nathan W. Churchill Robyn Spring Babak Afshin-Pour Fan Dong Stephen C. Strother 《PloS one》2015,10(7)
BOLD fMRI is sensitive to blood-oxygenation changes correlated with brain function; however, it is limited by relatively weak signal and significant noise confounds. Many preprocessing algorithms have been developed to control noise and improve signal detection in fMRI. Although the chosen set of preprocessing and analysis steps (the “pipeline”) significantly affects signal detection, pipelines are rarely quantitatively validated in the neuroimaging literature, due to complex preprocessing interactions. This paper outlines and validates an adaptive resampling framework for evaluating and optimizing preprocessing choices by optimizing data-driven metrics of task prediction and spatial reproducibility. Compared to standard “fixed” preprocessing pipelines, this optimization approach significantly improves independent validation measures of within-subject test-retest, and between-subject activation overlap, and behavioural prediction accuracy. We demonstrate that preprocessing choices function as implicit model regularizers, and that improvements due to pipeline optimization generalize across a range of simple to complex experimental tasks and analysis models. Results are shown for brief scanning sessions (<3 minutes each), demonstrating that with pipeline optimization, it is possible to obtain reliable results and brain-behaviour correlations in relatively small datasets. 相似文献
999.
Marnie L. Fusco Takao Hashiguchi Robyn Cassan Julia E. Biggins Charles D. Murin Kelly L. Warfield Sheng Li Frederick W. Holtsberg Sergey Shulenin Hong Vu Gene G. Olinger Do H. Kim Kevin J. Whaley Larry Zeitlin Andrew B. Ward Cory Nykiforuk M. Javad Aman Jody Berry Erica Ollmann Saphire 《PLoS pathogens》2015,11(6)
The filoviruses, which include the marburg- and ebolaviruses, have caused multiple outbreaks among humans this decade. Antibodies against the filovirus surface glycoprotein (GP) have been shown to provide life-saving therapy in nonhuman primates, but such antibodies are generally virus-specific. Many monoclonal antibodies (mAbs) have been described against Ebola virus. In contrast, relatively few have been described against Marburg virus. Here we present ten mAbs elicited by immunization of mice using recombinant mucin-deleted GPs from different Marburg virus (MARV) strains. Surprisingly, two of the mAbs raised against MARV GP also cross-react with the mucin-deleted GP cores of all tested ebolaviruses (Ebola, Sudan, Bundibugyo, Reston), but these epitopes are masked differently by the mucin-like domains themselves. The most efficacious mAbs in this panel were found to recognize a novel “wing” feature on the GP2 subunit that is unique to Marburg and does not exist in Ebola. Two of these anti-wing antibodies confer 90 and 100% protection, respectively, one hour post-exposure in mice challenged with MARV. 相似文献
1000.
Matthew J. Cheesman Matthew J. Traylor Margaret E. Hilton Katelyn E. Richards Matthew C. Taylor Phillip J. Daborn Robyn J. Russell Elizabeth M.J. Gillam John G. Oakeshott 《Insect biochemistry and molecular biology》2013,43(5):455-465
Cytochrome P450 CYP6G1 has been implicated in the resistance of Drosophila melanogaster to numerous pesticides. While in vivo and in vitro studies have provided insight to the diverse functions of this enzyme, direct studies on the isolated CYP6G1 enzyme have not been possible due to the need for a source of recombinant enzyme. In the current study, the Cyp6g1 gene was isolated from D. melanogaster and re-engineered for heterologous expression in Escherichia coli. Approximately 460 nmol L?1 of P450 holoenzyme were obtained in 500 mL cultures. The recombinant enzyme was located predominantly within the bacterial cytosol. A two-step purification protocol using Ni-chelate affinity chromatography followed by removal of detergent on a hydroxyapatite column produced essentially homogenous enzyme from both soluble and membrane fractions. Recombinant CYP6G1 exhibited p-nitroanisole O-dealkylation activity but was not active against eleven other typical P450 marker substrates. Substrate-induced binding spectra and IC50 values for inhibition of p-nitroanisole O-dealkylation were obtained for a wide selection of pesticides, namely DDT, imidacloprid, chlorfenvinphos, malathion, endosulfan, dieldrin, dicyclanil, lufenuron and carbaryl, supporting previous in vivo and in vitro studies on Drosophila that have suggested that the enzyme is involved in multi-pesticide resistance in insects. 相似文献