Élimination des composés pharmaceutiques des eaux de rejets hospitaliers par oxydation par voie humide

Les eaux usées sont une voie d’entrée pour les médicaments dans nos rivières, car les traitements actuels ne sont pas appropriés pour ces composés. Les hôpitaux sont une source à considérer étant donné leurs eaux usées chargées en composés pharmaceutiques. C’est dans l’optique de répondre au problème de déchargement de médicaments dans l’environnement par les effluents hospitaliers que ce projet est né. Parmi les innombrables possibilités de traitement, l’oxydation par voie humide (OVH), un processus d’oxydation avancé qui utilise de l'air et de l'eau à des températures et des pressions élevées pour éliminer les composés organiques, semble une voie prometteuse. L’objectif du projet était d’évaluer l’application de l’OVH comme prétraitement des eaux usées des hôpitaux afin de retirer les composés pharmaceutiques avant de rejoindre les eaux usées municipales. Afin de répondre au but de cette recherche, les dix composés les plus problématiques d’un hôpital local ont été déterminés selon leur abondance et toxicité, une méthode de quantification par spectrométrie de masse a été développée pour suivre les performances de dégradation et les paramètres du traitement à l’étude ont été optimisés. En complément, des analyses d’écotoxicité ont été réalisées afin d’évaluer l’impact du traitement sur la toxicité des effluents générés ainsi qu’une analyse technico-économique pour évaluer la faisabilité économique de son application en contexte réel. L’étude a démontré que l’OVH atteint une performance de dégradation entre 95.0 et 99.1% des composés dopés à 10 µg/L dans des eaux usées hospitalières en seulement 15 minutes d’oxydation et ce même à faible demande chimique en oxygène (< 600 mg O2/L). Les produits de dégradation générés semblent néanmoins plus toxiques que les produits de départ selon les tests de toxicité effectués sur un crustacé (Daphnia magna) et une bactérie (Aliivibrio fischeri). Les analyses ont également révélé un coût de 27$ par mètre cube. Ce chiffre pourrait toutefois être moindre en préconcentrant l’effluent hospitalier d’abord. Ces résultats sont un bon point de départ pour permettre aux collaborateurs du projet de continuer à développer leur procédé pilote en mode continu et ainsi arriver à trouver l’application la plus probable pour cette technologie verte. Le sujet a fait l’objet de présentation à un comité de gestion de l’environnement dans le réseau de la santé et certains acteurs portaient un intérêt pour cette technologie dans le cadre de la construction d’un nouvel hôpital au Québec. Il y a assurément une préoccupation sur le terrain et un désir de trouver des solutions environnementales. Ce genre de recherche apporte les connaissances nécessaires pour y répondre. Les suites du projet vont se tourner vers les produits de transformation afin de découvrir l’éventail de molécules générées par la dégradation des composés primaires durant le procédé. Il serait également intéressant d’étudier la corrélation entre toxicité et biodégradabilité en fonction du temps d’oxydation

Acceptabilité de l’autoévaluation des patients âgés traités au Département d’urgence

Introduction : Il est recommandé que les patients âgés subissent un dépistage gériatrique systématique au Département d’urgence (DU). Cependant, il est difficile pour les cliniciens de respecter cette recommandation dans la pratique. L’autoévaluation pourrait être une solution intéressante à ce problème, mais l'évaluation de l’acceptabilité de cette pratique, étape fondamentale de l’évaluation d’une intervention, n’a pas encore été effectuée. Hypothèse et objectifs : Notre hypothèse est que l’autoévaluation est aussi acceptable que l’évaluation par un professionnel. L’objectif principal de cette étude était de comparer l’acceptabilité de l’autoévaluation par les patients âgés au DU à celle de l’évaluation par un professionnel, selon les personnes âgées et leurs proches. Méthode : Devis : Étude croisée randomisée qui a eu lieu entre mai et juillet 2018. Participants : Patients âgés de ≥65 ans au DU et leur proche. Mesures : Un professionnel a évalué la fragilité, le statut cognitif et fonctionnel des participants, qui ont également fait leur autoévaluation avec une tablette électronique. L’ordre des évaluations était randomisé. L’acceptabilité était évaluée avec le Treatment Acceptability and Preferences (TAP). Analyses : Des analyses descriptives ont été effectuées pour les variables sociodémographiques. Les scores TAP ont été ajustés avec une régression linéaire multivariée. Une analyse de contenu thématique des données qualitatives a été réalisée. Résultats : 67 patients ont été inclus. L’âge moyen était de 75.5±8.0 et 55.2% étaient des femmes. Les scores TAP ajustés étaient de 2.20 pour l’autoévaluation et 2.36 pour l’évaluation par un professionnel (p=0.08). Une différence entre les scores est observée (p=0.01) chez les patients ≥85ans (n=11), ce qui pourrait être attribué à l’utilisation de la technologie selon notre analyse de contenu thématique. La taille d'échantillon relativement petite des proches (n=9) nous a empêchés d'effectuer des tests statistiques. Conclusion : Nos résultats démontrent que les patients âgés perçoivent l’autoévaluation à l’aide d’une tablette électronique au DU tout aussi acceptable qu’une évaluation par un professionnel.Introduction: It is recommended that seniors consulting to the Emergency Department (ED) undergoa comprehensive geriatric screening, which is difficult for most EDs. Patient self-assessment using electronic tablet could be an interesting solution to this issue. However, the acceptability of self assessment by older ED patients remains unknown. Assessing acceptability is a fundamental step in evaluating new interventions. The main objective of this project was to compare the acceptability of older patient self-assessment in the ED to a standard assessment made by a professional, according to seniors and their caregivers. Methods: Design: This randomized crossover design cohort study took place between May and July 2018. Participants: 1) Patients aged ≥65 years consulting to the ED, 2) their caregiver, when present. Measurements: A professional assessed frailty, cognitive and functional status of patients, who also performed self-assessment using an electronic tablet. A randomization list determined the order of test administration. Acceptability was measured using the Treatment Acceptability and Preferences (TAP) questionnaires – a high score indicates a higher level of acceptability. Analyses: Descriptive analyses were performed for sociodemographic variables. Scores were adjusted for confounding variables using multivariate linear regression. Thematic content analysis was performed for qualitative data. Results: 67 patients were included. Mean age was 75.5±8.0 and 55.2% were women. Adjusted TAP scores for RA evaluation and patient self-assessment were 2.4 and 2.2, respectively. We found no difference between the two types of evaluations (p= 0.08). Patients aged ≥85 (n=11) showed a difference between the TAPs scores (p=0.01). However our qualitative data indicates that this mightbe attributed to the use of technology. Data from 9 caregivers showed a 2.4 mean TAP score for RA evaluation and 2.4 for self-assessment. Conclusions: Our results show that older patients find self-assessment in the ED using an electronic tablet just as acceptable as a standard evaluation by a professional

Reducing Ammonia Losses By Adding FeCI3 During Composting Of Sewage Sludge

The release of ammonia nitrogen during composting of sewage sludge mixed with a lignocellulosic bulking agent leads to a reduction in the agronomic value of the final compost and to harmful effects on the environment. We propose adding a cheap salt FeCl3 which can be used without special precaution to reduce ammonia losses by decreasing pH conditions. An in-vessel co-composting experiment was conducted in a large reactor (100 L) in which FeCl3 was added to sludge mixed with a bulking agent (pine shavings and sawdust) and compared with a control mixture without FeCl3. Temperature, oxygen consumption and pH were monitored throughout the composting of both mixtures. The final balance of organic matter, organic and inorganic nitrogen permitted to conclude that the addition of FeCl3 reduced nitrogen loss (by a factor of 2.4 in relation to the control) and increased mineralisation of the organic nitrogen by 1.6

Organic components of airborne dust influence the magnitude and kinetics of dendritic cell activation

Bioaerosol exposure in highly contaminated occupational settings is associated with an increased risk of disease. Yet, few determinants allow for accurate prediction of the immunopathogenic potential of complex bioaerosols. Since dendritic cells are instrumental to the initiation of immunopathological reactions, we studied how dendritic cell activation was modified in response to individual agents, combined microbial agents, or air sample eluates from highly contaminated environmental settings. We found that combinations of agents accelerated and enhanced the activation of in vitro-generated murine bone marrow-derived dendritic cell cultures, when compared to individual agents. We also determined that endotoxins are not sufficient to predict the potential of air samples to induce bone marrow-derived dendritic cell activation, especially when endotoxin levels are low. Importantly, bone marrow-derived dendritic cell activation stratified samples from three environmental settings (swine barns, dairy barns, and wastewater treatment plants) according to their air quality status. As a whole, these results support the notion that the interplay between bioaerosol components impacts on their ability to activate dendritic cells and that bone marrow-derived dendritic cell cultures are promising tools to study the immunomodulatory impact of air samples and their components

Lipoxin A4 Stimulates Calcium-Activated Chloride Currents and Increases Airway Surface Liquid Height in Normal and Cystic Fibrosis Airway Epithelia

Cystic Fibrosis (CF) is a genetic disease characterised by a deficit in epithelial Cl− secretion which in the lung leads to airway dehydration and a reduced Airway Surface Liquid (ASL) height. The endogenous lipoxin LXA4 is a member of the newly identified eicosanoids playing a key role in ending the inflammatory process. Levels of LXA4 are reported to be decreased in the airways of patients with CF. We have previously shown that in normal human bronchial epithelial cells, LXA4 produced a rapid and transient increase in intracellular Ca2+. We have investigated, the effect of LXA4 on Cl− secretion and the functional consequences on ASL generation in bronchial epithelial cells obtained from CF and non-CF patient biopsies and in bronchial epithelial cell lines. We found that LXA4 stimulated a rapid intracellular Ca2+ increase in all of the different CF bronchial epithelial cells tested. In non-CF and CF bronchial epithelia, LXA4 stimulated whole-cell Cl− currents which were inhibited by NPPB (calcium-activated Cl− channel inhibitor), BAPTA-AM (chelator of intracellular Ca2+) but not by CFTRinh-172 (CFTR inhibitor). We found, using confocal imaging, that LXA4 increased the ASL height in non-CF and in CF airway bronchial epithelia. The LXA4 effect on ASL height was sensitive to bumetanide, an inhibitor of transepithelial Cl− secretion. The LXA4 stimulation of intracellular Ca2+, whole-cell Cl− currents, conductances and ASL height were inhibited by Boc-2, a specific antagonist of the ALX/FPR2 receptor. Our results provide, for the first time, evidence for a novel role of LXA4 in the stimulation of intracellular Ca2+ signalling leading to Ca2+-activated Cl− secretion and enhanced ASL height in non-CF and CF bronchial epithelia

Use of a Novel Extremophilic Xylanase for an Environmentally Friendly Industrial Bleaching of Kraft Pulps

Xylanases can boost pulp bleachability in Elemental Chlorine Free (ECF) processes, but their industrial implementation for producing bleached kraft pulps is not straightforward. It requires enzymes to be active and stable at the extreme conditions of alkalinity and high temperature typical of this industrial process; most commercial enzymes are unable to withstand these conditions. In this work, a novel highly thermo and alkaline-tolerant xylanase from Pseudothermotoga thermarum was overproduced in E. coli and tested as a bleaching booster of hardwood kraft pulps to save chlorine dioxide (ClO2) during ECF bleaching. The extremozyme-stage (EXZ) was carried out at 90 °C and pH 10.5 and optimised at lab scale on an industrial oxygen-delignified eucalyptus pulp, enabling us to save 15% ClO2 to reach the mill brightness, and with no detrimental effect on paper properties. Then, the EXZ-assisted bleaching sequence was validated at pilot scale under industrial conditions, achieving 25% ClO2 savings and reducing the generation of organochlorinated compounds (AOX) by 18%, while maintaining pulp quality and papermaking properties. Technology reproducibility was confirmed with another industrial kraft pulp from a mix of hardwoods. The new enzymatic technology constitutes a realistic step towards environmentally friendly production of kraft pulps through industrial integration of biotechnology.This work was supported by WoodZymes project funded by the Bio-based Industries Joint Undertaking (BBI JU) under GA 792070. The BBI JU received support from the EU’s H2020 research and innovation programme and the Bio Based Industries Consortium.Peer reviewe

Usefulness and pitfalls of MAA SPECT/CT in identifying digestive extrahepatic uptake when planning liver radioembolization

International audiencePURPOSE: Identifying gastroduodenal uptake of (99m)Tc-macroaggregated albumin (MAA), which is associated with an increased risk of ulcer disease, is a crucial part of the therapeutic management of patients undergoing radioembolization for liver tumours. Given this context, the use of MAA single photon emission computed tomography (SPECT)/CT may be essential, but the procedure has still not been thoroughly evaluated. The aim of this retrospective study was to determine the effectiveness of MAA SPECT/CT in identifying digestive extrahepatic uptake, while determining potential diagnostic pitfalls. METHODS: Overall, 139 MAA SPECT/CT scans were performed on 103 patients with different hepatic tumour types. Patients were followed up for at least 6 months according to standard requirements. RESULTS: Digestive, or digestive-like, uptake other than free pertechnetate was identified in 5.7% of cases using planar imaging and in 36.6% of cases using SPECT/CT. Uptake sites identified by SPECT/CT included the gastroduodenal region (3.6%), gall bladder (12.2%), portal vein thrombosis (6.5%), hepatic artery (6.5%), coil embolization site (2.1%) as well as falciform artery (5.0%). For 2.1% of explorations, a coregistration error between SPECT and CT imaging could have led to a false diagnosis by erroneously attributing an uptake site to the stomach or gall bladder, when the uptake actually occurred in the liver. CONCLUSION: SPECT/CT is more efficacious than planar imaging in identifying digestive extrahepatic uptake sites, with extrahepatic uptake observed in one third of scans using the former procedure. However, more than half of the uptake sites in our study were vascular in nature, without therapeutic implications. The risk of coregistration errors must also be kept in mind

Impact of brain overgrowth on sensorial learning processing during the first year of life

Macrocephaly is present in about 2–5% of the general population. It can be found as an isolated benign trait or as part of a syndromic condition. Brain overgrowth has been associated with neurodevelopmental disorders such as autism during the first year of life, however, evidence remains inconclusive. Furthermore, most of the studies have involved pathological or high-risk populations, but little is known about the effects of brain overgrowth on neurodevelopment in otherwise neurotypical infants. We investigated the impact of brain overgrowth on basic perceptual learning processes (repetition effects and change detection response) during the first year of life. We recorded high density electroencephalograms (EEG) in 116 full-term healthy infants aged between 3 and 11 months, 35 macrocephalic (14 girls) and 81 normocephalic (39 girls) classified according to the WHO head circumference norms. We used an adapted oddball paradigm, time-frequency analyses, and auditory event-related brain potentials (ERPs) to investigate differences between groups. We show that brain overgrowth has a significant impact on repetition effects and change detection response in the 10–20 Hz frequency band, and in N450 latency, suggesting that these correlates of sensorial learning processes are sensitive to brain overgrowth during the first year of life