1,326 research outputs found
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Benefit:Risk Profile of Budesonide in Obstructive Airways Disease
Airway inflammation is a major contributing factor in both asthma and chronic obstructive pulmonary disease (COPD) and represents an important target for treatment. Inhaled corticosteroids (ICS) as monotherapy or in combination therapy with long-acting β2-agonists or long-acting muscarinic antagonists are used extensively in the treatment of asthma and COPD. The development of ICS for their anti-inflammatory properties progressed through efforts to increase topical potency and minimise systemic potency and through advances in inhaled delivery technology. Budesonide is a potent, non-halogenated ICS that was developed in the early 1970s and is now one of the most widely used lung medicines worldwide. Inhaled budesonide's physiochemical and pharmacokinetic/pharmacodynamic properties allow it to reach a rapid and high airway efficacy due to its more balanced relationship between water solubility and lipophilicity. When absorbed from the airways and lung tissue, its moderate lipophilicity shortens systemic exposure, and its unique property of intracellular esterification acts like a sustained release mechanism within airway tissues, contributing to its airway selectivity and a low risk of adverse events. There is a large volume of clinical evidence supporting the efficacy and safety of budesonide, both alone and in combination with the fast- and long-acting β2-agonist formoterol, as maintenance therapy in patients with asthma and with COPD. The combination of budesonide/formoterol can also be used as an as-needed reliever with anti-inflammatory properties, with or without regular maintenance for asthma, a novel approach that is already approved by some country-specific regulatory authorities and currently recommended in the Global Initiative for Asthma (GINA) guidelines. Budesonide remains one of the most well-established and versatile of the inhaled anti-inflammatory drugs. This narrative review provides a clinical reappraisal of the benefit:risk profile of budesonide in the management of asthma and COPD
RAD54 family translocases counter genotoxic effects of RAD51 in human tumor cells.
The RAD54 family DNA translocases have several biochemical activities. One activity, demonstrated previously for the budding yeast translocases, is ATPase-dependent disruption of RAD51-dsDNA binding. This activity is thought to promote dissociation of RAD51 from heteroduplex DNA following strand exchange during homologous recombination. In addition, previous experiments in budding yeast have shown that the same activity of Rad54 removes Rad51 from undamaged sites on chromosomes; mutants lacking Rad54 accumulate nonrepair-associated complexes that can block growth and lead to chromosome loss. Here, we show that human RAD54 also promotes the dissociation of RAD51 from dsDNA and not ssDNA. We also show that translocase depletion in tumor cell lines leads to the accumulation of RAD51 on chromosomes, forming complexes that are not associated with markers of DNA damage. We further show that combined depletion of RAD54L and RAD54B and/or artificial induction of RAD51 overexpression blocks replication and promotes chromosome segregation defects. These results support a model in which RAD54L and RAD54B counteract genome-destabilizing effects of direct binding of RAD51 to dsDNA in human tumor cells. Thus, in addition to having genome-stabilizing DNA repair activity, human RAD51 has genome-destabilizing activity when expressed at high levels, as is the case in many human tumors
Validation of plaster endocast morphology through 3D CT image analysis
A crucial component of research on brain evolution has been the comparison of fossil endocranial surfaces with modern human and primate endocrania. The latter have generally been obtained by creating endocasts out of rubber latex shells filled with plaster. The extent to which the method of production introduces errors in endocast replicas is unknown. We demonstrate a powerful method of comparing complex shapes in 3-dimensions (3D) that is broadly applicable to a wide range of paleoanthropological questions. Pairs of virtual endocasts (VEs) created from high-resolution CT scans of corresponding latex/plaster endocasts and their associated crania were rigidly registered (aligned) in 3D space for two Homo sapiens and two Pan troglodytes specimens. Distances between each cranial VE and its corresponding latex/plaster VE were then mapped on a voxel-by-voxel basis. The results show that between 79.7% and 91.0% of the voxels in the four latex/plaster VEs are within 2 mm of their corresponding cranial VEs surfaces. The average error is relatively small, and variation in the pattern of error across the surfaces appears to be generally random overall. However, inferior areas around the cranial base and the temporal poles were somewhat overestimated in both human and chimpanzee specimens, and the area overlaying Broca's area in humans was somewhat underestimated. This study gives an idea of the size of possible error inherent in latex/plaster endocasts, indicating the level of confidence we can have with studies relying on comparisons between them and, e.g., hominid fossil endocasts. Am J Phys Anthropol, 2007. © 2006 Wiley-Liss, Inc.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/55857/1/20499_ftp.pd
Confronting 3 Dimensional Time-dependent Jet Simulations with HST Observations
We perform state-of-the-art, 3D, time-dependent simulations of magnetized
disk winds, carried out to simulation scales of 60 Astronomical Units, in order
to confront optical HST observations of protostellar jets. We ``observe'' the
optical forbidden line emission produced by shocks within our simulated jets
and compare these with actual observations. Our simulations reproduce the rich
structure of time varying jets, including jet rotation far from the source, an
inner (up to 400 km/s) and outer (less than 100 km/s) component of the jet, and
jet widths of up to 20 Astronomical Units in agreement with observed jets.
These simulations when compared with the data are able to constrain disk wind
models. In particular, models featuring a disk magnetic field with a modest
radial spatial variation across the disk are favored.Comment: Accepted for publication in Ap
Signal transduction in light-oxygen-voltage receptors lacking the adduct- forming cysteine residue
Light–oxygen–voltage (LOV) receptors sense blue light through the
photochemical generation of a covalent adduct between a flavin-nucleotide
chromophore and a strictly conserved cysteine residue. Here we show that,
after cysteine removal, the circadian-clock LOV-protein Vivid still undergoes
light-induced dimerization and signalling because of flavin photoreduction to
the neutral semiquinone (NSQ). Similarly, photoreduction of the engineered LOV
histidine kinase YF1 to the NSQ modulates activity and downstream effects on
gene expression. Signal transduction in both proteins hence hinges on flavin
protonation, which is common to both the cysteinyl adduct and the NSQ. This
general mechanism is also conserved by natural cysteine-less, LOV-like
regulators that respond to chemical or photoreduction of their flavin
cofactors. As LOV proteins can react to light even when devoid of the adduct-
forming cysteine, modern LOV photoreceptors may have arisen from ancestral
redox-active flavoproteins. The ability to tune LOV reactivity through
photoreduction may have important implications for LOV mechanism and
optogenetic applications
Video-rate fluorescence diffuse optical tomography for in vivo sentinel lymph node imaging
We have developed a fiber-based, video-rate fluorescence diffuse optical tomography (DOT) system for noninvasive in vivo sentinel lymph node (SLN) mapping. Concurrent acquisition of fluorescence and reference signals allowed the efficient generation of ratio-metric data for 3D image reconstruction. Accurate depth localization and high sensitivity to fluorescent targets were established in to depths of >10 mm. In vivo accumulation of indocyanine green (ICG) dye was imaged in the region of the SLN following intradermal injection into the forepaw of rats. These results suggest that video-rate fluorescence DOT has significant potential as a clinical tool for noninvasive mapping of SLN
Hazards Analysis and Failure Modes and Effects Criticality Analysis (FMECA) of Four Concept Vehicle Propulsion Systems
The primary objective of this research effort is to identify failure modes and hazards associated with the concept vehicles and to perform functional hazard analyses (FHA) and failure modes and effects criticality analyses (FMECA) for each. Boeing also created a Fault Tree Analysis (FTA) for each of the concept vehicles, as the FTA contains the connectivity between systems and is an accepted, top-down method to analyze the safety of an air-vehicle. Conceptual design of notional powertrain configuration for each of four (4) NASA RVLT (Revolutionary Vertical Lift Technology) Concept Vehicles were developed in as much detail as was necessary to support the reliability and safety analysis for this project. Functional block diagrams from each of the conceptual powertrain configurations were created and used to order the FHA, FMECA, and FTA. Hazards were identified and the severity of each were categorized in the FHA for use in a follow-up FMECA. The FTA took inputs from the FMECA and the functional block diagrams to develop the connectivity and develop a quantitative architecture that could be used to perform sensitivity studies, as related to vehicle safety.Guidelines for reliability targets for both the air vehicle and the operation in the UAM (Urban Air Mobility) mission are discussed. An industry literature search was performed in order to assess gaps in existing government regulations and industry specifications. The industry literature search led to air-vehicle and operational reliability discussions, as related to Distributed Electric/Hybrid-Electric Propulsion (DE/HEP) system operating in the UAM role. A discussion of results and recommendations for future work is also provided
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REDUCE-IT USA: Results From the 3146 Patients Randomized in the United States.
BackgroundSome trials have found that patients from the United States derive less benefit than patients enrolled outside the United States. This prespecified REDUCE-IT (Reduction of Cardiovascular Events with Icosapent Ethyl - Intervention Trial) subgroup analysis was conducted to determine the degree of benefit of icosapent ethyl in the United States.MethodsREDUCE-IT randomized 8179 statin-treated patients with qualifying triglycerides ≥135 and <500 mg/dL and low-density lipoprotein cholesterol >40 and ≤100 mg/dL and a history of atherosclerosis or diabetes mellitus to icosapent ethyl 4 g/d or placebo. The primary composite end point was cardiovascular death, nonfatal myocardial infarction, nonfatal stroke, coronary revascularization, or hospitalization for unstable angina. The key secondary composite end point was cardiovascular death, nonfatal myocardial infarction, or nonfatal stroke. A hierarchy was prespecified for examination of individual and composite end points.ResultsA total of 3146 US patients (38.5% of the trial) were randomized and followed for a median of 4.9 years; 32.3% were women and 9.7% were Hispanic. The primary composite end point occurred in 24.7% of placebo-treated patients versus 18.2% of icosapent ethyl-treated patients (hazard ratio [HR], 0.69 [95% CI, 0.59-0.80]; P=0.000001); the key secondary composite end point occurred in 16.6% versus 12.1% (HR, 0.69 [95% CI, 0.57-0.83]; P=0.00008). All prespecified hierarchical end points were meaningfully and significantly reduced, including cardiovascular death (6.7% to 4.7%; HR, 0.66 [95% CI, 0.49-0.90]; P=0.007), myocardial infarction (8.8% to 6.7%; HR, 0.72 [95% CI, 0.56-0.93]; P=0.01), stroke (4.1% to 2.6%; HR, 0.63 [95% CI, 0.43-0.93]; P=0.02), and all-cause mortality (9.8% to 7.2%; HR, 0.70 [95% CI, 0.55-0.90]; P=0.004); for all-cause mortality in the US versus non-US patients, Pinteraction=0.02. Safety and tolerability findings were consistent with the full study cohort.ConclusionsWhereas the non-US subgroup showed significant reductions in the primary and key secondary end points, the US subgroup demonstrated particularly robust risk reductions across a variety of individual and composite end points, including all-cause mortality.Clinical trial registrationURL: https://www.clinicaltrials.gov. Unique identifier: NCT01492361
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