50 research outputs found

    Nitrous oxide abuse direct measurement for diagnosis and follow-up: update on kinetics and impact on metabolic pathways.

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    peer reviewedRecreational use of nitrous oxide (N2O) has become a major health issue worldwide, with a high number of clinical events, especially in neurology and cardiology. It is essential to be able to detect and monitor N2O abuse to provide effective care and follow-up to these patients. Current recommendations for detecting N2O in cases of recreational misuse and consumption markers are lacking. We aimed to update current knowledge through a review of the literature on N2O measurement and kinetics. We reviewed the outcomes of experiments, whether in preclinical models (in vitro or in vivo), or in humans, with the aim to identify biomarkers of intoxication as well as biomarkers of clinical severity, for laboratory use. Because N2O is eliminated 5 min after inhalation, measuring it in exhaled air is of no value. Many studies have found that urine and blood matrices concentrations are connected to ambient concentrations, but there is no similar data for direct exposure. There have been no studies on N2O measurement in direct consumers. Currently, patients actively abusing N2O are monitored using effect biomarkers (biomarkers related to the effects of N2O on metabolism), such as vitamin B12, homocysteine and methylmalonic acid

    Toxicity of fine and quasi-ultrafine particles: focus on the effects of extractable and non-extractable matter fractions

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    Air pollution represents today one of the major risk factors for human health. An important part of this threat is due to the presence in the atmosphere of fine particulate matter (PM2.5_{2.5}). PM2.5_{2.5} forms a heterogeneous mixture of inorganic pollutants (metals, ions
), organic pollutants (volatile organic compounds (VOC), polycyclic aromatic hydrocarbons (PAHs), dioxins, polychlorobiphenyls (PCBs)
), and biological contaminants (pollen, bacteria, fungi
). To date many studies have demonstrated the toxicity of PAHs and some metals, but so far, no study has been able to clearly attribute the toxicological effects observed to a class of pollutants. Therefore, this study aims to determine the physicochemical characteristics of PM2.5−0.3_{2.5-0.3} and PM0,3_{0,3} and to compare the toxicity of native PM2.5−0.3_{2.5-0.3}, organic fractions of fine (EOM2.5−0.3_{2.5-0.3}) and quasi ultrafine particles (OEM0.3_{0.3}), and PM2.5−0.3_{2.5-0.3} freed from this organic fraction (dPM2.5−0.3_{2.5-0.3}) on BEAS-2B cells in culture. Fine and quasi-ultrafine particles were sampled in the southern suburb of Beirut, Lebanon. Chemical characterization showed that quasi-ultrafine particles were about 40 times more concentrated in PAHs than fines one suggesting a significant influence of anthropogenic activities and combustion sources (industries, road traffic and electric generators) on the emission of quasi-ultrafine particles. The influence of combustion sources was confirmed by investigation of PAHs diagnostic ratios. In addition, BEAS-2B cells exposed to PM2.5−0.3_{2.5-0.3}, dPM2.5−0.3_{2.5-0.3}, EOM2.5−0.3_{2.5-0.3} and EOM0.3_{0.3} lead to different results concerning metabolic activation of PAHs pathway and proteins expression of biomarkers implicated in the pathway of genotoxicity. Globally, EOM0.3_{0.3} was the most inducer for phase I and phase II enzymes implicated in the metabolic activation of PAHs (AhR, AhRR, ARNT, Cyp1A1, Cyp1B1, EPHX-1, GSTA-4) and EOM0.3_{0.3} induced DNA damage, felt by ATR and followed by a cascade of protein phosphorylations contributing to the cell cycle arrest (P21 and P53 induction)

    Les risques liés à l'usage d'un médicament banalisé (exemple du paracétamol)

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    LILLE2-BU Santé-Recherche (593502101) / SudocSudocFranceF

    Exposition professionnelle aux pesticides des travailleurs agricoles

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    LILLE2-BU Santé-Recherche (593502101) / SudocSudocFranceF

    Scaling and anisotropic heterogeneities of ocean SST images from satellite data

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    International audienceOceanic fields display a large variability over large temporal and spatial scales. One way to characterize such variability, borrowed from the field of turbulence, is to consider scaling regimes and multi-scaling properties

    Multi-scale coastal surface temperature in the Bay of Biscay and the English Channel

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    International audienceThe Bay of Biscay and the English Channel, in the Northeastern Atlantic, are considered as a natural laboratory to explore the coastal dynamics at different spatial and temporal scales. In those regions, the coastal circulation is constrained by a complex topography (e.g. varying width of the continental shelf, canyons), river runoffs, strong tides and a seasonally contrasted wind-driven circulation. Based on different numerical model experiments (from 400m to 4km spatial resolution, from 40 to 100 sigma vertical layers using 3D primitive equation ocean models), different features of the Bay of Biscay and English Channel circulation are assessed and explored. Both spatial (submesoscale and mesoscale) and temporal (from hourly to monthly) scales are considered. Modelled spatial scales, with a specific focus on the variability of fine scale features (e.g. fronts, filaments, eddies), are compared with remotely sensed observations (i.e. Sea Surface Temperature). Different methodologies as singularity and Lyapunov exponents allow describing fine scales features and are applied on both modelled and observed datasets. For temporal scales, in situ high frequency surface temperature measurements from coastal moorings (from COAST-HF observing network) provide a reference for the temporal variability to be modelled. Exploring differences in the temporal scales (from an Empirical Mode Decomposition) advises on the efficiency of our coastal modelling approach. This result overview in the Bay of Biscay and the English Channel aims illustrating the input of coastal modelling activities in understanding multi-scale interactions (spatial and temporal)

    Sequential conditioning in unfavorable AML: a single center experience

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    44th Annual Meeting of the European-Society-for-Blood-and-Marrow-Transplantation (EBMT), Lisbon, PORTUGAL, MAR 18-21, 2018International audienc
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