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21.
M. Guillaume Wientjes 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1991,563(2)
A high-performance liquid chromatographic analysis for the anti-AIDS drug 2',3'-dideoxyinosine (ddI) in rat plasma and urine, with a limit of detection of 0.2 μg/ml and requiring a sample size of 100 μl is described. Diluted plasma or urine samples were extracted using a C18 solid-phase extraction column. Retention of ddI on more polar solid-phase extraction columns was insufficient for sample clean-up. This method is useful for pharmacokinetic studies of ddI in small rodents. 相似文献
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Cdric Annweiler Mlinda Beaudenon Jennifer Gautier Justine Gonsard Sophie Boucher Guillaume Chapelet Astrid Darsonval Bertrand Fougre Olivier Gurin Marjorie Houvet Pierre Mnager Claire Roubaud-Baudron Achille Tchalla Jean-Claude Souberbielle Jrmie Riou Elsa Parot-Schinkel Thomas Clarier 《PLoS medicine》2022,19(5)
BackgroundVitamin D supplementation has been proposed as a treatment for Coronavirus Disease 2019 (COVID-19) based on experimental data and data from small and uncontrolled observational studies. The COvid19 and VITamin d TRIAL (COVIT-TRIAL) study was conducted to test whether a single oral high dose of cholecalciferol (vitamin D3) administered within 72 hours after the diagnosis of COVID-19 improves, compared to standard-dose cholecalciferol, the 14-day overall survival among at-risk older adults infected with Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2).Methods and findingsThis multicenter, randomized, controlled, open-label, superiority trial involved collaboration of 9 medical centers in France. Patients admitted to the hospital units or living in nursing homes adjacent to the investigator centers were eligible if they were ≥65 years, had SARS-CoV-2 infection of less than 3 days, and at least 1 COVID-19 worsening risk factor (among age ≥75 years, SpO2 ≤94%, or PaO2/FiO2 ≤300 mm Hg). Main noninclusion criteria were organ failure requiring ICU, SpO2 ≤92% despite 5 L/min oxygen, life expectancy <3 months, vitamin D supplementation >800 IU/day during the preceding month, and contraindications to vitamin D supplements. Eligible and consenting patients were randomly allocated to either a single oral high-dose (400,000 IU) or standard-dose (50,000 IU) cholecalciferol administered under medical supervision within 72 hours after the diagnosis of COVID-19. Participants and local study staff were not masked to the allocated treatment, but the Steering Committee and the Data and Safety Monitoring Board were masked to the randomization group and outcome data during the trial. The primary outcome was 14-day overall mortality. Between April 15 and December 17, 2020, of 1,207 patients who were assessed for eligibility in the COVIT-TRIAL study, 254 met eligibility criteria and formed the intention-to-treat population. The median age was 88 (IQR, 82 to 92) years, and 148 patients (58%) were women. Overall, 8 (6%) of 127 patients allocated to high-dose cholecalciferol, and 14 (11%) of 127 patients allocated to standard-dose cholecalciferol died within 14 days (adjusted hazard ratio = 0.39 [95% confidence interval [CI], 0.16 to 0.99], P = 0.049, after controlling for randomization strata [i.e., age, oxygen requirement, hospitalization, use of antibiotics, anti-infective drugs, and/or corticosteroids] and baseline imbalances in important prognostic factors [i.e., sex, ongoing cancers, profuse diarrhea, and delirium at baseline]). The number needed to treat for one person to benefit (NNTB) was 21 [NNTB 9 to ∞ to number needed to treat for one person to harm (NNTH) 46]. Apparent benefits were also found on 14-day mortality due to COVID-19 (7 (6%) deaths in high-dose group and 14 (11%) deaths in standard-dose group; adjusted hazard ratio = 0.33 [95% CI, 0.12 to 0.86], P = 0.02). The protective effect of the single oral high-dose administration was not sustained at 28 days (19 (15%) deaths in high-dose group and 21 (17%) deaths in standard-dose group; adjusted hazard ratio = 0.70 [95% CI, 0.36 to 1.36], P = 0.29). High-dose cholecalciferol did not result in more frequent adverse effects compared to the standard dose. The open-label design and limited study power are the main limitations of the study.ConclusionsIn this randomized controlled trial (RCT), we observed that the early administration of high-dose versus standard-dose vitamin D3 to at-risk older patients with COVID-19 improved overall mortality at day 14. The effect was no longer observed after 28 days.Trial registrationClinicalTrials.gov .In a randomized trial, Cedric Annweiler and colleagues evaluate whether a single high dose of vitamin D3 improves survival among older adults in France with SARS-CoV-2 infection. NCT04344041相似文献
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A unified framework to model the potential and realized distributions of invasive species within the invaded range
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Tarek Hattab Carol X. Garzón‐López Michael Ewald Sandra Skowronek Raf Aerts Hélène Horen Boris Brasseur Emilie Gallet‐Moron Fabien Spicher Guillaume Decocq Hannes Feilhauer Olivier Honnay Pieter Kempeneers Sebastian Schmidtlein Ben Somers Ruben Van De Kerchove Duccio Rocchini Jonathan Lenoir 《Diversity & distributions》2017,23(7):806-819
26.
A Virulence and Antimicrobial Resistance DNA Microarray Detects a High Frequency of Virulence Genes in Escherichia coli Isolates from Great Lakes Recreational Waters
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Katia Hamelin Guillaume Bruant Abdel El-Shaarawi Stephen Hill Thomas A. Edge Sadjia Bekal John Morris Fairbrother Jose Harel Christine Maynard Luke Masson Roland Brousseau 《Applied microbiology》2006,72(6):4200-4206
Escherichia coli is generally described as a commensal species with occasional pathogenic strains. Due to technological limitations, there is currently little information concerning the prevalence of pathogenic E. coli strains in the environment. For the first time, using a DNA microarray capable of detecting all currently described virulence genes and commonly found antimicrobial resistance genes, a survey of environmental E. coli isolates from recreational waters was carried out. A high proportion (29%) of 308 isolates from a beach site in the Great Lakes carried a pathotype set of virulence-related genes, and 14% carried antimicrobial resistance genes, findings consistent with a potential risk for public health. The results also showed that another 8% of the isolates had unusual virulence gene combinations that would be missed by conventional screening. This new application of a DNA microarray to environmental waters will likely have an important impact on public health, epidemiology, and microbial ecology in the future. 相似文献
27.
The significance of clubbed antennae in grasshoppers was assessed by investigating the sensilla repertoire of 15 gomphocerine species. The influence of the diet type (graminivorous or polyphagous) and the apical thickening of antenna on the number of sensilla were tested. It appears that the antennal thickening has a stronger impact on the number of sensilla than the food mode. The species bearing clubbed antennae are globally low in olfactive and contact sensilla, maybe in relation with a more complex courtship, but are richer in mechanoreceptors, probably involved in the control of antenna movements. The food mode change from oligophagy to polyphagy is not associated to an increase in the number of olfactive or contact sensilla. In contrast, the high number of these sensilla in a monophagous grasshopper feeding on Ulex bushes is interpreted in the context of alkaloid detection. 相似文献
28.
Choice of Allocations and Constructs for Attributional or Consequential Life Cycle Assessment and Input‐Output Analysis
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Guillaume Majeau‐Bettez Thomas Dandres Stefan Pauliuk Richard Wood Edgar Hertwich Réjean Samson Anders Hammer Strømman 《Journal of Industrial Ecology》2018,22(4):656-670
The divide between attributional and consequential research perspectives partly overlaps with the long‐standing methodological discussions in the life cycle assessment (LCA) and input‐output analysis (IO) research communities on the choice of techniques and models for dealing with situations of coproduction. The recent harmonization of LCA allocations and IO constructs revealed a more diverse set of coproduction models than had previously been understood. This increased flexibility and transparency in inventory modeling warrants a re‐evaluation of the treatment of coproduction in analyses with attributional and consequential perspectives. In the present article, the main types of coproductions situations and of coproduction models are reviewed, along with key desirable characteristics of attributional and consequential studies. A concordance analysis leads to clear recommendations, which call for important refinements to current guidelines for both LCA/IO practitioners and database developers. We notably challenge the simple association between, on the one hand, attributional LCA and partition allocation, and on the one hand, consequential LCA and substitution modeling. 相似文献
29.
Gabrielle Thiébaut Guillaume Tixier François Guérold Serge Muller 《Hydrobiologia》2006,570(1):159-164
The aim of our study was to assess the water quality of the upper Moselle river by using biological indices. Simultaneous
physico-chemical surveys were also undertaken from May 1999 to April 2000. Twelve sampling sites were selected in order to
provide a wide range of potential pollution. Chemical analysis did not reveal any major problem of pollution. However a lower
water quality resulting from domestic pollution was established for some sampling sites. A biological monitoring combining
both macroinvertebrates and macrophytes was performed. Biological indices based on plant community structure and macrophyte
composition were not pertinent tools, whereas simple indices based on taxonomic richness of particular groups of macroinvertebrates
were strongly correlated with several chemical parameters, showing that such simple biological variables should represent
powerful indicators of ecosystem degradation. 相似文献
30.
Marc J. Leblanc Christian Leduc Frank Stagnitti Peter J. van Oevelen Chris Jones Linus A. Mofor Moumtaz Razack Guillaume Favreau 《Palaeogeography, Palaeoclimatology, Palaeoecology》2006,230(3-4):230-242
The existence of a very large Lake Chad during the late Quaternary, Megalake Chad, has long been questioned. A Megalake Chad would present strong evidence for climatic fluctuations of great magnitude during the Holocene in tropical Africa. In this paper we used satellite data from Landsat and Modis sensors to collect and analyse new information on landforms in a 2 000 000 km2 region of the Lake Chad Basin. We detected 2300 km of remains marking the ancient shoreline of Megalake Chad. The satellite data also indicated many Saharan rivers and relict deltas leading to the long paleoshoreline. Large dunefield flattenings were observed and interpreted as the result of wave-cut erosion by the paleolake. Similarities were noticed between the landforms observed along the paleoshoreline of Megalake Chad and that of the former Aral Sea. This finding has significant consequences for reconstructing paleohydrology and paleoenvironments through the Lake Chad basin, and continental climate change. 相似文献