200 research outputs found
Transmission of methicillin-resistant Staphylococcus aureus in long-term care facilities and their related healthcare networks.
BACKGROUND: Long-term care facilities (LTCF) are potential reservoirs for methicillin-resistant Staphylococcus aureus (MRSA), control of which may reduce MRSA transmission and infection elsewhere in the healthcare system. Whole-genome sequencing (WGS) has been used successfully to understand MRSA epidemiology and transmission in hospitals and has the potential to identify transmission between these and LTCF. METHODS: Two prospective observational studies of MRSA carriage were conducted in LTCF in England and Ireland. MRSA isolates were whole-genome sequenced and analyzed using established methods. Genomic data were available for MRSA isolated in the local healthcare systems (isolates submitted by hospitals and general practitioners). RESULTS: We sequenced a total of 181 MRSA isolates from the two study sites. The majority of MRSA were multilocus sequence type (ST)22. WGS identified one likely transmission event between residents in the English LTCF and three putative transmission events in the Irish LTCF. WGS also identified closely related isolates present in colonized Irish residents and their immediate environment. Based on phylogenetic reconstruction, closely related MRSA clades were identified between the LTCF and their healthcare referral network, together with putative MRSA acquisition by LTCF residents during hospital admission. CONCLUSIONS: These data confirm that MRSA is transmitted between residents of LTCF and is both acquired and transmitted to others in referral hospitals and beyond. Our data present compelling evidence for the importance of environmental contamination in MRSA transmission, reinforcing the importance of environmental cleaning. The use of WGS in this study highlights the need to consider infection control in hospitals and community healthcare facilities as a continuum.UKCRC Translational Infection Research (TIR) Initiative, Medical Research Council (Grant ID: G1000803), Biotechnology and Biological Sciences Research Council, National Institute for Health Research, Chief Scientist Office of the Scottish Government Health Directorate, Hospital Infection Society (Major Research Grant), Wellcome Trust (Grant ID: 098051), Academy of Medical Sciences, Health Foundation, National Institute for Health Research Cambridge Biomedical Research Centr
Outcomes of highly active antiretroviral therapy in the context of universal access to healthcare: the U.S. Military HIV Natural History Study
<p>Abstract</p> <p>Background</p> <p>To examine the outcomes of highly-active antiretroviral therapy (HAART) for individuals with free access to healthcare, we evaluated 2327 patients in a cohort study composed of military personnel and beneficiaries with HIV infection who initiated HAART from 1996 to the end of 2007.</p> <p>Methods</p> <p>Outcomes analyzed were virologic suppression (VS) and failure (VF), CD4 count changes, AIDS and death. VF was defined as never suppressing or having at least one rebound event. Multivariate (MV) analyses stratified by the HAART initiation year (before or after 2000) were performed to identify risk factors associated with these outcomes.</p> <p>Results</p> <p>Among patients who started HAART after 2000, 81% had VS at 1 year (N = 1,759), 85% at 5 years (N = 1,061), and 82% at 8 years (N = 735). Five years post-HAART, the median CD4 increase was 247 cells/ml and 34% experienced VF. AIDS and mortality rates at 5 years were 2% and 0.3%, respectively. In a MV model adjusted for known risk factors associated with treatment response, being on active duty (versus retired) at HAART initiation was associated with a decreased risk of AIDS (HR = 0.6, 95% CI 0.4-1.0) and mortality (0.6, 0.3-0.9), an increased probability of CD4 increase ≥ 50% (1.2, 1.0-1.4), but was not significant for VF.</p> <p>Conclusions</p> <p>In this observational cohort, VS rates approach those described in clinical trials. Initiating HAART on active duty was associated with even better outcomes. These findings support the notion that free access to healthcare likely improves the response to HAART thereby reducing HIV-related morbidity and mortality.</p
The role of microRNA-155/liver X receptor pathway in experimental and idiopathic pulmonary fibrosis
Background:
Idiopathic Pulmonary Fibrosis (IPF) is progressive and rapidly fatal. Improved understanding of pathogenesis is required to prosper novel therapeutics. Epigenetic changes contribute to IPF therefore microRNAs may reveal novel pathogenic pathways.
Objectives:
To determine the regulatory role of microRNA(miR)-155 in the pro-fibrotic function of murine lung macrophages and fibroblasts, IPF lung fibroblasts and its contribution to experimental pulmonary fibrosis.
Methods:
Bleomycin-induced lung fibrosis in wild-type and miR-155-/- mice was analyzed by histology, collagen and pro-fibrotic gene expression. Mechanisms were identified by in silico and molecular approaches; validated in mouse lung fibroblasts and macrophages, and in IPF lung fibroblasts, using loss-and-gain of function assays, and in vivo using specific inhibitors.
Results: miR-155-/- mice developed exacerbated lung fibrosis, increased collagen deposition, collagen 1 and 3 mRNA expression, TGFβ production, and activation of alternatively-activated macrophages, contributed by deregulation of the microRNA-155 target gene the liver X receptor (LXR)α in lung fibroblasts and macrophages. Inhibition of LXRα in experimental lung fibrosis and in IPF lung fibroblasts reduced the exacerbated fibrotic response. Similarly, enforced expression of miR-155 reduced the pro-fibrotic phenotype of IPF and miR-155-/- fibroblasts.
Conclusion:
We describe herein a molecular pathway comprising miR-155 and its epigenetic LXRα target that when deregulated enables pathogenic pulmonary fibrosis. Manipulation of the miR-155/LXR pathway may have therapeutic potential for IPF
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Isotope data from amino acids indicate Darwin's ground sloth was not an herbivore.
Fossil sloths are regarded as obligate herbivores for reasons including peculiarities of their craniodental morphology and that all living sloths feed exclusively on plants. We challenge this view based on isotopic analyses of nitrogen of specific amino acids, which show that Darwin's ground sloth Mylodon darwinii was an opportunistic omnivore. This direct evidence of omnivory in an ancient sloth requires reevaluation of the ecological structure of South American Cenozoic mammalian communities, as sloths represented a major component of these ecosystems across the past 34 Myr. Furthermore, by analyzing modern mammals with known diets, we provide a basis for reliable interpretation of nitrogen isotopes of amino acids of fossils. We argue that a widely used equation to determine trophic position is unnecessary, and that the relative isotopic values of the amino acids glutamate and phenylalanine alone permit reliable reconstructions of trophic positions of extant and extinct mammals
Seasonal and Long-Term Changes in Relative Abundance of Bull Sharks from a Tourist Shark Feeding Site in Fiji
Shark tourism has become increasingly popular, but remains controversial because
of major concerns originating from the need of tour operators to use bait or
chum to reliably attract sharks. We used direct underwater sampling to document
changes in bull shark Carcharhinus leucas relative abundance at
the Shark Reef Marine Reserve, a shark feeding site in Fiji, and the
reproductive cycle of the species in Fijian waters. Between 2003 and 2009, the
total number of C. leucas counted on each day ranged from 0 to
40. Whereas the number of C. leucas counted at the feeding site
increased over the years, shark numbers decreased over the course of a calendar
year with fewest animals counted in November. Externally visible reproductive
status information indicates that the species' seasonal departure from the
feeding site may be related to reproductive activity
Improved reference genome for the domestic horse increases assembly contiguity and composition
Theodore Kalbfleisch et al. present an improved genome assembly for the domestic horse by combining short- and long-read data, as well as proximity ligation data. They improve contiguity of the assembly by 40-fold, with a 10-fold reduction in gaps
The Eighth Data Release of the Sloan Digital Sky Survey: First Data from SDSS-III
The Sloan Digital Sky Survey (SDSS) started a new phase in August 2008, with
new instrumentation and new surveys focused on Galactic structure and chemical
evolution, measurements of the baryon oscillation feature in the clustering of
galaxies and the quasar Ly alpha forest, and a radial velocity search for
planets around ~8000 stars. This paper describes the first data release of
SDSS-III (and the eighth counting from the beginning of the SDSS). The release
includes five-band imaging of roughly 5200 deg^2 in the Southern Galactic Cap,
bringing the total footprint of the SDSS imaging to 14,555 deg^2, or over a
third of the Celestial Sphere. All the imaging data have been reprocessed with
an improved sky-subtraction algorithm and a final, self-consistent photometric
recalibration and flat-field determination. This release also includes all data
from the second phase of the Sloan Extension for Galactic Understanding and
Evolution (SEGUE-2), consisting of spectroscopy of approximately 118,000 stars
at both high and low Galactic latitudes. All the more than half a million
stellar spectra obtained with the SDSS spectrograph have been reprocessed
through an improved stellar parameters pipeline, which has better determination
of metallicity for high metallicity stars.Comment: Astrophysical Journal Supplements, in press (minor updates from
submitted version
A spatially resolved analysis of star-formation burstiness by comparing UV and H in galaxies at z1 with UVCANDELS
The UltraViolet imaging of the Cosmic Assembly Near-infrared Deep
Extragalactic Legacy Survey Fields (UVCANDELS) program provides HST/UVIS F275W
imaging for four CANDELS fields. We combine this UV imaging with existing
HST/near-IR grism spectroscopy from 3D-HST+AGHAST to directly compare the
resolved rest-frame UV and H emission for a sample of 979 galaxies at
spanning a range in stellar mass of . Since
both rest-UV and H are sensitive to on-going star-formation but over
different timescales, their resolved comparison allows us to infer the
burstiness in star-formation as a function of galaxy structural parameters. We
generate homogenized maps of rest-UV and H emission for all galaxies in
our sample and stack them to compute the average UV-to-H luminosity
ratio as a function of galactocentric radius. We find that galaxies below
stellar mass of , at all radii, have a UV-to-H
ratio higher than the equilibrium value expected from constant star-formation,
indicating a significant contribution from bursty star-formation. Even for
galaxies with stellar mass , the UV-to-H ratio
is elevated towards in their outskirts (), suggesting that
bursty star-formation is likely prevalent in the outskirts of even the most
massive galaxies but is likely over-shadowed by their brighter cores.
Furthermore, we present the UV-to-H ratio as a function of galaxy
surface brightness, a proxy for stellar mass surface density, and find that
regions below are consistent with bursty
star-formation, regardless of their galaxy stellar mass, potentially suggesting
that local star-formation is independent of global galaxy properties at the
smallest scales.Comment: 19 pages, 8 figures; submitted to Ap
Adenovirus-mediated Expression of Aquaporin-5 in Epithelial Cells
A recombinant adenovirus coding for rat aquaporin-5 was constructed and plaque purified. The recombinant adenovirus (AdrAQP5) mediated the expression of aquaporin-5 in rat and human salivary cell lines and in dog kidney cells in vitro as demonstrated by Northern blot and Western blot analyses, and by confocal microscopy after immunofluorescent labeling. In kidney cells, expression of the transgene was optimal if cells were infected at their basolateral surface, a phenomenon associated with the distribution of integrin receptors on these cells. The expressed aquaporin-5 protein was functionally active because viral-mediated gene transfer resulted in a significant increase in the osmotically directed net fluid secretion rate across monolayers of kidney cells. AdrAQP5 should provide an efficient and useful means to impart facilitated water permeability to cells lacking such a pathway
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