3,520 research outputs found
Reappraisal of COVID-19 Risk for Patients with Inflammatory Bowel Disease (IBD): Withdrawal of the British Society of Gastroenterology IBD Risk Grid
Early in the pandemic, there was significant concern about how COVID-19 may impact patients
with inflammatory bowel disease (IBD). Would IBD, as a chronic immune-mediated condition, be
a risk factor for more severe COVID-19? Would medications used to treat IBD, in particularly
immunosuppressants, increase the likelihood of hospitalization or death due to COVID-19?
However, at the start of the pandemic there was a paucity of data to guide decision making for
patients with IBD. In this setting, many national and international societies issued statements on
management of IBD to provide initial guidance to gastroenterologists and patients with IBD. The
British Society of Gastroenterology (BSG) published an IBD risk grid for COVID-19 severity in
April 2020 that proposed a framework for categorizing patients with IBD into those more likely to
be vulnerable to COVID-19 primarily based on co-morbidities and disease characteristics.
Patients deemed at moderate risk were advised to practice stringent social distancing while those
at high risk were recommended to practice “shielding,” the strictest advice for isolating from
others. The authors of the BSG IBD risk grid recently issued a statement withdrawing this
guidance noting a number of factors including that the vast majority of IBD patients are not at
increased risk of adverse COVID-19 outcomes, the reduced severity of disease with recent
variants, and the effectiveness of COVID-19 vaccines
Novel anti-obesity quercetin-derived Q2 prevents metabolic disorders in rats fed with high-fat diet
Objective: Obesity is often accompanied by an increased morbidity and mortality due to an increase of the cardiovascular disease risk factors, diabetes mellitus and dyslipidemia. Research is constantly working on protective molecules against obesity. In the present study, a novel Quercetin derivative Q2 was synthesized to overcome the poor bioavailability and low stability of Quercetin, a natural flavonoid with antioxidative and antiobesity properties.
Methods: Rats were fed (12ws) with normodiet (fat:INS; 6.2%), High Fat Diet (fat:60%), HFDINS; +INS; Q2 in water (500INS; nM). Metabolic and anthropometric parameters were measured. 3T3-L1 preadipocytes were incubated with Q2 (1-25μM) and the differentiation program was evaluated by lipid accumulation through ORO staining. Gene and protein expression levels were assessed by RT-PCR and Western blot analysis.
Results: Compared to HFD, HFDINS; +INS; Q2 rats showed reduced body weight, abdominal obesity, dyslipidemia and improved glucose tolerance. This is associated to lower adipose and liver modifications compared to hypertrophy and steatosis observed in HFD. In 3T3-L1 cells, lipid accumulation was significantly impaired by treatment with Q2. Indeed, Q2 significantly decreased the expression of the main adipogenic markers, c/EBPα and PPARγ both at mRNA and protein level.
Conclusions: Our results indicate that Q2 markedly decreases differentiation of 3T3-L1 preadipocytes and contributes to prevent metabolic disorders as well as adipose and liver alterations typical of severe obesity induced by a HFD
Novel Data Acquisition System for Silicon Tracking Detectors
We have developed a novel data acquisition system for measuring tracking
parameters of a silicon detector in a particle beam. The system is based on a
commercial Analog-to-Digital VME module and a PC Linux based Data Acquisition
System. This DAQ is realized with C++ code using object-oriented techniques.
Track parameters for the beam particles were reconstructed using off-line
analysis code and automatic detector position alignment algorithm.
The new DAQ was used to test novel Czochralski type silicon detectors. The
important silicon detector parameters, including signal size distributions and
signal to noise distributions, were successfully extracted from the detector
under study. The efficiency of the detector was measured to be 95 %, the
resolution about 10 micrometers, and the signal to noise ratio about 10.Comment: Talk from the 2003 Computing in High Energy and Nuclear Physics
(CHEP03), La Jolla, Ca, USA, March 2003, 6 pages, LaTeX, 5 eps figures. PSN
TUGP00
The CLAS12 Software Framework and Event Reconstruction
We describe offline event reconstruction for the CEBAF Large Acceptance Spectrometer at 12 GeV (CLAS12), including an overview of the offline reconstruction framework and software tools, a description of the algorithms developed for the individual detector subsystems, and the overall approach for charged and neutral particle identification. We also present the scheme for data processing and the code management procedures
Measurement of Two-Photon Exchange Effect by Comparing Elastic e ± p Cross Sections
Background: The electromagnetic form factors of the proton measured by unpolarized and polarized electron scattering experiments show a significant disagreement that grows with the squared four-momentum transfer (Q2) . Calculations have shown that the two measurements can be largely reconciled by accounting for the contributions of two-photon exchange (TPE). TPE effects are not typically included in the standard set of radiative corrections since theoretical calculations of the TPE effects are highly model dependent, and, until recently, no direct evidence of significant TPE effects has been observed.
Purpose: We measured the ratio of positron-proton to electron-proton elastic-scattering cross sections in order to determine the TPE contribution to elastic electron-proton scattering and thereby resolve the proton electric form factor discrepancy.
Methods: We produced a mixed simultaneous electron-positron beam in Jefferson Lab\u27s Hall B by passing the 5.6-GeV primary electron beam through a radiator to produce a bremsstrahlung photon beam and then passing the photon beam through a convertor to produce electron-positron pairs. The mixed electron-positron (lepton) beam with useful energies from approximately 0.85 to 3.5 GeV then struck a 30-cm-long liquid hydrogen (LH2) target located within the CEBAF Large Acceptance Spectrometer (CLAS). By detecting both the scattered leptons and the recoiling protons, we identified and reconstructed elastic scattering events and determined the incident lepton energy. A detailed description of the experiment is presented.
Results: We present previously unpublished results for the quantity R2γ , the TPE correction to the elastic-scattering cross section, at Q2 ≈ 0.85 and 1.45 GeV2 over a large range of virtual photon polarization ɛ .
Conclusions: Our results, along with recently published results from VEPP-3, demonstrate a nonzero contribution from TPE effects and are in excellent agreement with the calculations that include TPE effects and largely reconcile the form-factor discrepancy up to Q2 ≈ 2 GeV2 . These data are consistent with an increase in R2γ with decreasing ɛ at Q2 ≈ 0.85 and 1.45 GeV2 . There are indications of a slight increase in R2γ with Q2
Resistance and resilience of ecosystem descriptors and properties to dystrophic events: a study case in a Mediterranean lagoon
Mediterranean lagoons are naturally exposed, during the dry season, to dystrophic and hypoxic events determining dis-equilibrium conditions along temporal and spatial scales, which are linked to metabolism and life cycle of the biotic components. In summer 2008, Lesina lagoon (SE Italian coastline) was interested by a geographically localized dystrophic crisis which affected up to 8% of the total lagoon surface. Temporal dynamics of principal descriptors of abiotic (water, sediment) and biotic (phytoplankton, benthic macroinvertebrate) compartments have been followed during the 2008 by collecting data inside stressed and control lagoon areas before a dystrophic event and in the six months after the dystrophic event. The aim of the study was to analyse the pathways of ecosystem responses to dystrophic stress, searching for the characteristic scales of ecosystem compartment resistance and resilience. The characteristic time-scale of abiotic and biotic component time responses varied from days, for the selected markers of the water column, to year, for the benthic ones. Short-term biotic and abiotic responses in the water column were strongly coupled while biotic and abiotic responses at the sediment level were remarkably un-coupled. Dynamics and recovery time of water column and benthic components do not match in Lesina following the dystrophic crisis, highlighting an intrinsic individualistic behavior within the lagoon community driving ecosystem processes and ecosystem level responses. Taxonomic and non-taxonomic descriptors of both phytoplankton and benthic macroinvertebrates showed different response patterns as early warning signals and overall resilience. The emphasized differences in the stability components, i.e., resistance and resilience, of water column and sediment abiotic and biotic characteristics as well as of taxonomic and non-taxonomic descriptors has key implication in planning monitoring strategies and programs for transitional waters in the Mediterranean and Black Sea EcoRegions
Unitary Isobar Model - MAID2007
The unitary isobar model MAID2007 has been developed to analyze the world
data of pion photo- and electroproduction. The model contains both a common
background and several resonance terms. The background is unitarized according
to the K-matrix prescription, and the 13 four-star resonances with masses below
2 GeV are described by appropriately unitarized Breit-Wigner forms. The data
have been analyzed by both single-energy and global fits, and the transverse
and longitudinal helicity amplitudes have been extracted for the four-star
resonances below 2 GeV. Because of its inherent simplicity, MAID2007 is well
adopted for predictions and analysis of the observables in pion photo- and
electroproduction.Comment: 32 pages including 13 tables and 24 figure
Shorter Disease Duration Is Associated With Higher Rates of Response to Vedolizumab in Patients With Crohn\u27s Disease But Not Ulcerative Colitis.
BACKGROUND & AIMS: Patients with Crohn\u27s disease (CD), but not ulcerative colitis (UC), of shorter duration have higher rates of response to tumor necrosis factor (TNF) antagonists than patients with longer disease duration. Little is known about the association between disease duration and response to other biologic agents. We aimed to evaluate response of patients with CD or UC to vedolizumab, stratified by disease duration.
METHODS: We analyzed data from a retrospective, multicenter, consortium of patients with CD (n = 650) or UC (n = 437) treated with vedolizumab from May 2014 through December 2016. Using time to event analyses, we compared rates of clinical remission, corticosteroid-free remission (CSFR), and endoscopic remission between patients with early-stage (≤2 years duration) and later-stage (\u3e2 years) CD or UC. We used Cox proportional hazards models to identify factors associated with outcomes.
RESULTS: Within 6 months initiation of treatment with vedolizumab, significantly higher proportions of patients with early-stage CD, vs later-stage CD, achieved clinical remission (38% vs 23%), CSFR (43% vs 14%), and endoscopic remission (29% vs 13%) (P \u3c .05 for all comparisons). After adjusting for disease-related factors including previous exposure to TNF antagonists, patients with early-stage CD were significantly more likely than patients with later-stage CD to achieve clinical remission (adjusted hazard ratio [aHR], 1.59; 95% CI, 1.02-2.49), CSFR (aHR, 3.39; 95% CI, 1.66-6.92), and endoscopic remission (aHR, 1.90; 95% CI, 1.06-3.39). In contrast, disease duration was not a significant predictor of response among patients with UC.
CONCLUSIONS: Patients with CD for 2 years or less are significantly more likely to achieve a complete response, CSFR, or endoscopic response to vedolizumab than patients with longer disease duration. Disease duration does not associate with response vedolizumab in patients with UC
- …