148 research outputs found
Impact of reduced vancomycin susceptibility on the therapeutic outcome of MRSA bloodstream infections
<p>Abstract</p> <p>Background</p> <p>The aim of this study was to determine whether clinical outcome of patients with methicillin-resistant <it>Staphylococcus aureus </it>(MRSA) bacteraemia was correlated with vancomycin susceptibility of the corresponding strains.</p> <p>Methods</p> <p>A retrospective study on MRSA bacteraemia was performed at a teaching hospital between January 1998 and October 2005 by linking vancomycin susceptibility profiles of patients' isolates with hospitalization data.</p> <p>Results</p> <p>A total of 20 out of 209 MRSA bacteraemia patients were treated with vancomycin for at least 5 days with adequate trough levels, and fulfilled the study's inclusion and exclusion criteria. Twenty-two <it>S. aureus </it>isolates from these patients' blood cultures were identified as MRSA, including two <it>hetero</it>-VISA from separate patients and two VISA with vancomycin MIC of 4 mg/L from one patient. Between patients who showed 'good' vancomycin response and patients who did not, there was a significant difference (p < 0.01) in their corresponding MRSAs' vancomycin susceptibility expressed by 'area under curve' (AUC) of population analysis. Significant correlations were found between AUC and initial vancomycin therapeutic response parameters of 'days till afebrile' (<it>r </it>= 0.828, p < 0.01) and 'days till CRP ≦ 30% of maximum' (<it>r </it>= 0.627, p < 0.01)</p> <p>Conclusion</p> <p>Our study results caution healthcare personnel that early consideration should be given to cases with a poor vancomycin treatment response that could signify the involvement of MRSA with reduced susceptibility to vancomycin.</p
First results on the cluster galaxy population from the Subaru Hyper Suprime-Cam survey. II. Faint end color-magnitude diagrams and radial profiles of red and blue galaxies at
We present a statistical study of the redshift evolution of the cluster
galaxy population over a wide redshift range from 0.1 to 1.1, using
optically-selected CAMIRA clusters from ~deg of the Hyper
Suprime-Cam (HSC) Wide S16A data. Our stacking technique with a statistical
background subtraction reveals color-magnitude diagrams of red-sequence and
blue cluster galaxies down to faint magnitudes of . We find that
the linear relation of red-sequence galaxies in the color-magnitude diagram
extends down to the faintest magnitudes we explore with a small intrinsic
scatter . The scatter does not evolve significantly
with redshift. The stacked color-magnitude diagrams are used to define red and
blue galaxies in clusters for studying their radial number density profiles
without resorting to photometric redshifts of individual galaxies. We find that
red galaxies are significantly more concentrated toward cluster centers and
blue galaxies dominate the outskirt of clusters. We explore the fraction of red
galaxies in clusters as a function of redshift, and find that the red fraction
decreases with increasing distances from cluster centers. The red fraction
exhibits a moderate decrease with increasing redshift. The radial number
density profiles of cluster member galaxies are also used to infer the location
of the steepest slope in the three dimensional galaxy density profiles. For a
fixed threshold in richness, we find little redshift evolution in this
location.Comment: 18pages, 10 figures, accepted as PASJ special issu
A new quadruple gravitational lens from the Hyper Suprime-Cam Survey: the puzzle of HSC~J115252+004733
We report the serendipitous discovery of a quadruply lensed source at , HSC~J115252+004733, from the Hyper Suprime-Cam (HSC) Survey. The
source is lensed by an early-type galaxy at and a satellite
galaxy. Here, we investigate the properties of the source by studying its size
and luminosity from the imaging and the luminosity and velocity width of the
Ly- line from the spectrum. Our analyses suggest that the source is
most probably a low-luminosity active galactic nucleus (LLAGN) but the
possibility of it being a compact bright galaxy (e.g., a Lyman- emitter
or Lyman Break Galaxy) cannot be excluded. The brighter pair of lensed images
appears point-like except in the HSC -band (with a seeing ). The
extended emission in the -band image could be due to the host galaxy
underneath the AGN, or alternatively, due to a highly compact lensed galaxy
(without AGN) which appears point-like in all bands except in -band. We also
find that the flux ratio of the brighter pair of images is different in the
Ks-band compared to optical wavelengths. Phenomena such as differential
extinction and intrinsic variability cannot explain this chromatic variation.
While microlensing from stars in the foreground galaxy is less likely to be the
cause, it cannot be ruled out completely. If the galaxy hosts an AGN, then this
represents the highest redshift quadruply imaged AGN known to date, enabling
study of a distant LLAGN. Discovery of this unusually compact and faint source
demonstrates the potential of the HSC survey.Comment: 9 pages, 7 figures, 3 Tables, MNRAS accepted, text reduce
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