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991.
In 2008, one of the worst public health crises occurred in the state of Nevada,
where authorities discovered up to 63,000 patients were potentially exposed to
hepatitis C infection, largely due to substandard infection control and other
negligent practices at two endoscopy clinics in Las Vegas. In the subsequent
grand jury proceedings that followed, it was discovered that several clinic
employees not only participated in these egregious practices, but doctors,
nurses, and other health care professionals witnessed yet failed to report these
incidents, largely due to fears of whistleblower retaliation. In response, the
Nevada state legislature attempted to strengthen whistleblower protection laws,
but it remains unclear if such laws actually protect employees who attempt to
report patient safety concerns. As the push for quality patient outcomes becomes
more prominent with health care reform, whistleblower concerns must be
effectively addressed to ensure that health care professionals can report
patient safety concerns without fear of retaliation. 相似文献
992.
Hyun Seok Kim Saurabh Mendiratta Jiyeon Kim Chad Victor Pecot Jill E. Larsen Iryna Zubovych Bo Yeun Seo Jimi Kim Banu Eskiocak Hannah Chung Elizabeth McMillan Sherry Wu Jef De Brabander Kakajan Komurov Jason E. Toombs Shuguang Wei Michael Peyton Noelle Williams Adi F. Gazdar Bruce A. Posner Rolf A. Brekken Anil K. Sood Ralph J. Deberardinis Michael G. Roth John D. Minna Michael A. White 《Cell》2013
993.
Shuiquan Tang Winnie W. M. Chan Kelly E. Fletcher Jana Seifert Xiaoming Liang Frank E. L?ffler Elizabeth A. Edwards Lorenz Adrian 《Applied and environmental microbiology》2013,79(3):974-981
Dehalococcoides mccartyi strains are obligate organohalide-respiring bacteria harboring multiple distinct reductive dehalogenase (RDase) genes within their genomes. A major challenge is to identify substrates for the enzymes encoded by these RDase genes. We demonstrate an approach that involves blue native polyacrylamide gel electrophoresis (BN-PAGE) followed by enzyme activity assays with gel slices and subsequent identification of proteins in gel slices using liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS). RDase expression was investigated in cultures of Dehalococcoides mccartyi strain BAV1 and in the KB-1 consortium growing on chlorinated ethenes and 1,2-dichloroethane. In cultures of strain BAV1, BvcA was the only RDase detected, revealing that this enzyme catalyzes the dechlorination not only of vinyl chloride, but also of all dichloroethene isomers and 1,2-dichloroethane. In cultures of consortium KB-1, five distinct Dehalococcoides RDases and one Geobacter RDase were expressed under the conditions tested. Three of the five RDases included orthologs to the previously identified chlorinated ethene-dechlorinating enzymes VcrA, BvcA, and TceA. This study revealed substrate promiscuity for these three enzymes and provides a path forward to further explore the largely unknown RDase protein family. 相似文献
994.
Zi-Feng Jiang Fangfang Xia Kipp W. Johnson Christopher D. Brown Elizabeth Bartom Jigyasa H. Tuteja Rick Stevens Robert L. Grossman Marina Brumin Kevin P. White Murad Ghanim 《Applied and environmental microbiology》2013,79(5):1757-1759
“Candidatus Portiera aleyrodidarum” is the primary endosymbiont of whiteflies. We report two complete genome sequences of this bacterium from the worldwide invasive B and Q biotypes of the whitefly Bemisia tabaci. Differences in the two genome sequences may add insights into the complex differences in the biology of both biotypes. 相似文献
995.
Laura K. Strawn Yrjo T. Gr?hn Steven Warchocki Randy W. Worobo Elizabeth A. Bihn Martin Wiedmann 《Applied and environmental microbiology》2013,79(24):7618-7627
Identification of management practices associated with preharvest pathogen contamination of produce fields is crucial to the development of effective Good Agricultural Practices (GAPs). A cross-sectional study was conducted to (i) determine management practices associated with a Salmonella- or Listeria monocytogenes-positive field and (ii) quantify the frequency of these pathogens in irrigation and nonirrigation water sources. Over 5 weeks, 21 produce farms in New York State were visited. Field-level management practices were recorded for 263 fields, and 600 environmental samples (soil, drag swab, and water) were collected and analyzed for Salmonella and L. monocytogenes. Management practices were evaluated for their association with the presence of a pathogen-positive field. Salmonella and L. monocytogenes were detected in 6.1% and 17.5% of fields (n = 263) and 11% and 30% of water samples (n = 74), respectively. The majority of pathogen-positive water samples were from nonirrigation surface water sources. Multivariate analysis showed that manure application within a year increased the odds of a Salmonella-positive field (odds ratio [OR], 16.7), while the presence of a buffer zone had a protective effect (OR, 0.1). Irrigation (within 3 days of sample collection) (OR, 6.0), reported wildlife observation (within 3 days of sample collection) (OR, 6.1), and soil cultivation (within 7 days of sample collection) (OR, 2.9) all increased the likelihood of an L. monocytogenes-positive field. Our findings provide new data that will assist growers with science-based evaluation of their current GAPs and implementation of preventive controls that reduce the risk of preharvest contamination. 相似文献
996.
997.
Randall E. Mielke John H. Priester Rebecca A. Werlin Jeff Gelb Allison M. Horst Eduardo Orias Patricia A. Holden 《Applied and environmental microbiology》2013,79(18):5616-5624
Nanoscale titanium dioxide (TiO2) is increasingly used in consumer goods and is entering waste streams, thereby exposing and potentially affecting environmental microbes. Protozoans could either take up TiO2 directly from water and sediments or acquire TiO2 during bactivory (ingestion of bacteria) of TiO2-encrusted bacteria. Here, the route of exposure of the ciliated protozoan Tetrahymena thermophila to TiO2 was varied and the growth of, and uptake and accumulation of TiO2 by, T. thermophila were measured. While TiO2 did not affect T. thermophila swimming or cellular morphology, direct TiO2 exposure in rich growth medium resulted in a lower population yield. When TiO2 exposure was by bactivory of Pseudomonas aeruginosa, the T. thermophila population yield and growth rate were lower than those that occurred during the bactivory of non-TiO2-encrusted bacteria. Regardless of the feeding mode, T. thermophila cells internalized TiO2 into their food vacuoles. Biomagnification of TiO2 was not observed; this was attributed to the observation that TiO2 appeared to be unable to cross the food vacuole membrane and enter the cytoplasm. Nevertheless, our findings imply that TiO2 could be transferred into higher trophic levels within food webs and that the food web could be affected by the decreased growth rate and yield of organisms near the base of the web. 相似文献
998.
Wassim Azri Nicole Brunel Jérôme Franchel Ichrak Ben Rejeb Jean-Pierre Jacquot Jean-Louis Julien Stéphane Herbette Patricia Roeckel-Drevet 《Journal of plant physiology》2013
Gravity perception and gravitropic response are essential for plant development. In herbaceous species, it is widely accepted that one of the primary events in gravity perception involves the displacement of amyloplasts within specialized cells. However, the early signaling events leading to stem reorientation are not fully known, especially in woody species in which primary and secondary growth occur. Thirty-six percent of the identified proteins that were differentially expressed after gravistimulation were established as potential Thioredoxin targets. In addition, Thioredoxin h expression was induced following gravistimulation. In situ immunolocalization indicated that Thioredoxin h protein co-localized with the amyloplasts located in the endodermal cells. These investigations suggest the involvement of Thioredoxin h in the first events of signal transduction in inclined poplar stems, leading to reaction wood formation. 相似文献
999.
Capsule Faecal DNA gives accurate results of habitat use. 相似文献
1000.
Robert J. Fuller Elizabeth M. Humphreys Jeremy D. Wilson David G. Hoccom John Calladine 《Bird Study》2013,60(1):121-124
Capsule The machair of the Uists continues to support one of the most important assemblages of breeding waders in Europe, but there have been major variations in population change across the archipelago, the causes of which are poorly understood. 相似文献