59 research outputs found

    Matters of character

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    Notions of character are central to both normative and applied ethics. Over the past 15 years or so, a growing number of philosophers have advanced empirically-based critiques of virtue ethics, arguing for skepticism about character. I show how standard approaches to virtue ethics can be modified so as to avoid these rather damaging empirical critiques. The most promising responses to character skepticism, however, are not always available to virtue ethical approaches to applied ethics. In particular, I argue that virtue ethical approaches to business ethics are in need of novel responses to character skepticism or radical revision

    Feasibility pilot trial for the Trajectories of Recovery after Intravenous propofol versus inhaled VolatilE anesthesia (THRIVE) pragmatic randomised controlled trial

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    INTRODUCTION: Millions of patients receive general anaesthesia for surgery annually. Crucial gaps in evidence exist regarding which technique, propofol total intravenous anaesthesia (TIVA) or inhaled volatile anaesthesia (INVA), yields superior patient experience, safety and outcomes. The aim of this pilot study is to assess the feasibility of conducting a large comparative effectiveness trial assessing patient experiences and outcomes after receiving propofol TIVA or INVA. METHODS AND ANALYSIS: This protocol was cocreated by a diverse team, including patient partners with personal experience of TIVA or INVA. The design is a 300-patient, two-centre, randomised, feasibility pilot trial. Patients 18 years of age or older, undergoing elective non-cardiac surgery requiring general anaesthesia with a tracheal tube or laryngeal mask airway will be eligible. Patients will be randomised 1:1 to propofol TIVA or INVA, stratified by centre and procedural complexity. The feasibility endpoints include: (1) proportion of patients approached who agree to participate; (2) proportion of patients who receive their assigned randomised treatment; (3) completeness of outcomes data collection and (4) feasibility of data management procedures. Proportions and 95% CIs will be calculated to assess whether prespecified thresholds are met for the feasibility parameters. If the lower bounds of the 95% CI are above the thresholds of 10% for the proportion of patients agreeing to participate among those approached and 80% for compliance with treatment allocation for each randomised treatment group, this will suggest that our planned pragmatic 12 500-patient comparative effectiveness trial can likely be conducted successfully. Other feasibility outcomes and adverse events will be described. ETHICS AND DISSEMINATION: This study is approved by the ethics board at Washington University (IRB# 202205053), serving as the single Institutional Review Board for both participating sites. Recruitment began in September 2022. Dissemination plans include presentations at scientific conferences, scientific publications, internet-based educational materials and mass media. TRIAL REGISTRATION NUMBER: NCT05346588

    Drug-Based Lead Discovery: The Novel Ablative Antiretroviral Profile of Deferiprone in HIV-1-Infected Cells and in HIV-Infected Treatment-Naive Subjects of a Double-Blind, Placebo-Controlled, Randomized Exploratory Trial

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    Antiretrovirals suppress HIV-1 production yet spare the sites of HIV-1 production, the HIV-1 DNA-harboring cells that evade immune detection and enable viral resistance on-drug and viral rebound off-drug. Therapeutic ablation of pathogenic cells markedly improves the outcome of many diseases. We extend this strategy to HIV-1 infection. Using drug-based lead discovery, we report the concentration threshold-dependent antiretroviral action of the medicinal chelator deferiprone and validate preclinical findings by a proof-of-concept double-blind trial. In isolate-infected primary cultures, supra-threshold concentrations during deferiprone monotherapy caused decline of HIV-1 RNA and HIV-1 DNA; did not allow viral breakthrough for up to 35 days on-drug, indicating resiliency against viral resistance; and prevented, for at least 87 days off-drug, viral rebound. Displaying a steep dose-effect curve, deferiprone produced infection-independent deficiency of hydroxylated hypusyl-eIF5A. However, unhydroxylated deoxyhypusyl-eIF5A accumulated particularly in HIV-infected cells; they preferentially underwent apoptotic DNA fragmentation. Since the threshold, ascertained at about 150 mu M, is achievable in deferiprone-treated patients, we proceeded from cell culture directly to an exploratory trial. HIV-1 RNA was measured after 7 days on-drug and after 28 and 56 days off-drug. Subjects who attained supra-threshold concentrations in serum and completed the protocol of 17 oral doses, experienced a zidovudine-like decline of HIV-1 RNA on-drug that was maintained off-drug without statistically significant rebound for 8 weeks, over 670 times the drug\u27s half-life and thus clearance from circulation. The uniform deferiprone threshold is in agreement with mapping of, and crystallographic 3D-data on, the active site of deoxyhypusyl hydroxylase (DOHH), the eIF5A-hydroxylating enzyme. We propose that deficiency of hypusine-containing eIF5A impedes the translation of mRNAs encoding proline cluster (\u27polyproline\u27)-containing proteins, exemplified by Gag/p24, and facilitated by the excess of deoxyhypusine-containing eIF5A, releases the innate apoptotic defense of HIV-infected cells from viral blockade, thus depleting the cellular reservoir of HIV-1 DNA that drives breakthrough and rebound

    SYNTHESIS OF NANOSTRUCTURED FUELS: MIMICKING THE HIGH BURN-UP STRUCTURE

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    During its lifetime in the core of a nuclear reactor, the fuel undergoes significant changes in its physical, chemical and morphological characteristics. In outer regions of the fuel pellets so called "high burn-up" or "rim" structure is formed. In this region UO2 grains, with size about 10 μm in fresh dense fuel, are reorganized into a porous structure with grain size 0.1-0.3 μm and porosity fraction up to 20 %. The mechanical, thermal and fission product retention properties of the high burn-up structure have encouraged further interest and attempts to mimic this morphology in fresh fuel. The JRC-ITU has studied various techniques for synthesis of uranium and thorium dioxide in aqueous or nonaqueous media. Such nanoparticles can serve as starting material for production of material having similar characteristics as the high burn-up structure, as has been proved using Zr(Y)O2 nanoparticles. Recently, efforts have been focused on the compaction of the nanoparticle powders. A spark plasma sintering device (SPS, FCT Systeme GmbH) has been commissioned in the JRC-ITU and tested using various nonradioactive materials. The present study is oriented on pressing and sintering of Hf(Y)O2 and ZrO2 into nanostructured pellets. Final products have been characterized by optical and electron microscopy, X-ray powder diffraction and density measurements.JRC.E.4-Nuclear Fuel Safet

    Theophylline-7β-d-Ribofuranoside (Theonosine), a New Theophylline Metabolite Generated in Human and Animal Lung Tissue

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    While assessing the ability of mammalian lung tissue to metabolize theophylline, a new metabolite was isolated and characterized. The metabolite was produced by the microsomal fraction of lungs from several species, including rat, rabbit, dog, pig, sheep and human tissue. Metabolite production was blocked by boiling the microsomal tissue. This new metabolite, theophylline-7β-d-ribofuranoside (theonosine), was confirmed by several spectral methods and by comparison to an authentic synthetic compound. Tissue studies from rats, rabbits, dogs, and humans for cofactor involvement demonstrated an absolute requirement for NADP and enhanced metabolite production in the presence of magnesium ion. It remains to be demonstrated whether theonosine may contribute to the known pharmacological effects of theophylline

    Theophylline-7β-d-Ribofuranoside (Theonosine), a New Theophylline Metabolite Generated in Human and Animal Lung Tissue

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    While assessing the ability of mammalian lung tissue to metabolize theophylline, a new metabolite was isolated and characterized. The metabolite was produced by the microsomal fraction of lungs from several species, including rat, rabbit, dog, pig, sheep and human tissue. Metabolite production was blocked by boiling the microsomal tissue. This new metabolite, theophylline-7β-d-ribofuranoside (theonosine), was confirmed by several spectral methods and by comparison to an authentic synthetic compound. Tissue studies from rats, rabbits, dogs, and humans for cofactor involvement demonstrated an absolute requirement for NADP and enhanced metabolite production in the presence of magnesium ion. It remains to be demonstrated whether theonosine may contribute to the known pharmacological effects of theophylline

    Fission gas release from UO2 nuclear fuel: A review

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    Gaseous fission product generation, transport, and release can have a large impact on nuclear fuel performance, degrading fuel and fuel–cladding gap properties. Over the past several decades much progress has been made in understanding the key mechanisms of fission gas behavior through investigations with bulk reactor experiments and simplified analytical models. Concurrently, new mechanisms have come to light that can have a strong influence on gas release, especially the unexpected acceleration of fission gas release under high burn-up conditions. Additionally, novel modeling techniques, such as atomistic, mesoscale, and multiscale methods have joined the arsenal of investigative tools. In this review, existing research on the basic mechanisms of fission gas release during normal reactor operation is summarized, and critical areas where further work is needed are identified and discussed.JRC.G.I.5-Advanced Nuclear Knowledg
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