2,024 research outputs found
A Planetary lensing feature in caustic-crossing high-magnification microlensing events
Current microlensing follow-up observations focus on high-magnification
events because of the high efficiency of planet detection. However, central
perturbations of high-magnification events caused by a planet can also be
produced by a very close or a very wide binary companion, and the two kinds of
central perturbations are not generally distinguished without time consuming
detailed modeling (a planet-binary degeneracy). Hence, it is important to
resolve the planet-binary degeneracy that occurs in high-magnification events.
In this paper, we investigate caustic-crossing high-magnification events caused
by a planet and a wide binary companion. From this study, we find that because
of the different magnification excess patterns inside the central caustics
induced by the planet and the binary companion, the light curves of the
caustic-crossing planetary-lensing events exhibit a feature that is
discriminated from those of the caustic-crossing binary-lensing events, and the
feature can be used to immediately distinguish between the planetary and binary
companions. The planetary-lensing feature appears in the interpeak region
between the two peaks of the caustic-crossings. The structure of the interpeak
region for the planetary-lensing events is smooth and convex or boxy, whereas
the structure for the binary-lensing events is smooth and concave. We also
investigate the effect of a finite background source star on the
planetary-lensing feature in the caustic-crossing high-magnification events.
From this, we find that the convex-shaped interpeak structure appears in a
certain range that changes with the mass ratio of the planet to the
planet-hosting star.Comment: 14 pages, 4 figures. Accepted for publication in Ap
Src-family kinase-Cbl axis negatively regulates NLRP3 inflammasome activation.
Activation of the NLRP3 inflammasome is crucial for immune defense, but improper and excessive activation causes inflammatory diseases. We previously reported that Pyk2 is essential for NLRP3 inflammasome activation. Here we show that the Src-family kinases (SFKs)-Cbl axis plays a pivotal role in suppressing NLRP3 inflammasome activation in response to stimulation by nigericin or ATP, as assessed using gene knockout and gene knockdown cells, dominant active/negative mutants, and pharmacological inhibition. We reveal that the phosphorylation of Cbl is regulated by SFKs, and that phosphorylation of Cbl at Tyr371 suppresses NLRP3 inflammasome activation. Mechanistically, Cbl decreases the level of phosphorylated Pyk2 (p-Pyk2) through ubiquitination-mediated proteasomal degradation and reduces mitochondrial ROS (mtROS) production by contributing to the maintenance of mitochondrial size. The lower levels of p-Pyk2 and mtROS dampen NLRP3 inflammasome activation. In vivo, inhibition of Cbl with an analgesic drug, hydrocotarnine, increases inflammasome-mediated IL-18 secretion in the colon, and protects mice from dextran sulphate sodium-induced colitis. Together, our novel findings provide new insights into the role of the SFK-Cbl axis in suppressing NLRP3 inflammasome activation and identify a novel clinical utility of hydrocortanine for disease treatment
Epidemiology and outcomes of anal abscess in patients on chronic dialysis: a 14-year retrospective study
OBJECTIVES: We conducted this retrospective study to elucidate the clinical presentation and outcomes of anal abscess in chronic dialysis patients. METHODS: We performed a chart review of patients who were hospitalized for anal abscess from Jan. 2002 to Dec. 2015. A total of 3,074 episodes of anal abscess were identified. Of these, 43 chronic dialysis patients with first-time anal abscess were enrolled. Patients were divided into a surgical group and a nonsurgical group according to the treatment received during hospitalization. The baseline characteristics, clinical findings, treatments and outcomes were obtained and analyzed. The endpoints of this study were in-hospital mortality, one-year mortality and one-year recurrence. RESULTS: Of the 43 patients, 27 (62.7%) received surgical treatment, and 16 (37.2%) received antibiotic treatment alone. There was no significant difference in age, sex, body mass index, smoking habits, comorbidities, or dialysis characteristics between the two groups. Perianal abscess was the most common type of anal abscess, and 39.5% of patients experienced fistula formation. Most patients had mixed aerobic and anaerobic flora. Our data demonstrate that there was no significant difference in hospital stay, one-year survival or recurrence rate between the surgical group and nonsurgical group. However, there was a trend toward better in-hospital survival in patients who received surgical treatment (p=0.082). CONCLUSION: In chronic dialysis patients with anal abscess, there was no statistically significant difference in clinical presentation and outcomes between the surgical and nonsurgical groups, although the surgical group had a trend of better in-hospital survival
A New Application of the Astrometric Method to Break Severe Degeneracies in Binary Microlensing Events
When a source star is microlensed by one stellar component of a widely
separated binary stellar components, after finishing the lensing event, the
event induced by the other binary star can be additionally detected. In this
paper, we investigate whether the close/wide degeneracies in binary lensing
events can be resolved by detecting the additional centroid shift of the source
images induced by the secondary binary star in wide binary lensing events. From
this investigation, we find that if the source star passes close to the
Einstein ring of the secondary companion, the degeneracy can be easily resolved
by using future astrometric follow-up observations with high astrometric
precision. We determine the probability of detecting the additional centroid
shift in binary lensing events with high magnification. From this, we find that
the degeneracy of binary lensing events with a separation of AU
can be resolved with a significant efficiency. We also estimate the waiting
time for the detection of the additional centroid shift in wide binary lensing
events. We find that for typical Galactic lensing events with a separation of
AU, the additional centroid shift can be detected within 100
days, and thus the degeneracy of those events can be sufficiently broken within
a year.Comment: 13 pages, 4 figures, 1 table, accepted for publication in Ap
Implementation of central line-associated bloodstream infection prevention bundles in a surgical intensive care unit using peer tutoring
This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.Abstract
Background
Central line-associated bloodstream infections (CLABSIs) can be prevented through well-coordinated, multifaceted programs. However, implementation of CLABSI prevention programs requires individualized strategies for different institutional situations, and the best strategy in resource-limited settings is uncertain. Peer tutoring may be an efficient and effective method that is applicable in such settings.
Methods
A prospective intervention was performed to reduce CLABSIs in a surgical intensive care unit (SICU) at a tertiary hospital. The core interventions consisted of implementation of insertion and maintenance bundles for CLABSI prevention. The overall interventions were guided and coordinated by active educational programs using peer tutoring. The CLABSI rates were compared for 9Â months pre-intervention, 6Â months during the intervention and 9Â months post-intervention. The CLABSI rate was further observed for three years after the intervention.
Results
The rate of CLABSIs per 1000 catheter-days decreased from 6.9 infections in the pre-intervention period to 2.4 and 1.8 in the intervention (6Â m; PÂ =Â 0.102) and post-intervention (9Â m; PÂ =Â 0.036) periods, respectively. A regression model showed a significantly decreasing trend in the infection rate from the pre-intervention period (PÂ <Â 0.001), with incidence-rate ratios of 0.348 (95% confidence interval [CI], 0.98â1.23) in the intervention period and 0.257 (95% CI, 0.07â0.91) in the post-intervention period. However, after the 9-month post-intervention period, the yearly CLABSI rates reverted to 3.0â5.4 infections per 1000 catheter-days over 3Â years.
Conclusions
Implementation of CLABSI prevention bundles using peer tutoring in a resource-limited setting was useful and effectively reduced CLABSIs. However, maintaining the reduced CLABSI rate will require further strategies
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