Synthesis routes of CeO 2 nanoparticles dedicated to organophosphorus degradation: a benchmark

International audienceExposure to organophosphorus compounds, in military conflicts or terrorist acts, requires an emergency procedure including the availability of efficient decontamination systems. Systems based on nanosized cerium(IV) oxide (CeO$_{2}$) are highly promising candidates. CeO$_{2}$ is a heterogeneous catalyst for the degradation of the organophosphorus compounds such as VX agent or sarin. While the synthesis method influences the physicochemical characteristics of the nanoparticle surface and thus their degradation activity, we have compared the degradation activity of nanosized CeO$_{2}$ powders commercially available, or developed using different synthesis processes, namely hydrothermal process, photochemistry and laser ablation in liquids. The degradation activity was evaluated in vitro by measuring the degradation kinetics of paraoxon organophosphate. A quenching of the degradation activity is observed on the as-produced particles with a surface pollution, especially when organic molecules with carboxylate ion R–COO$^{-}$ are involved in the synthesis process. In contrast, laser-generated nanoparticles in ultra-pure water show the best activity, while the sample presents the lowest specific surface area. After annealing, almost all samples present a clean surface and the degradation activity is mainly driven by the specific surface area. We propose a figure of merit including the particle activity for the degradation of paraoxon, the production costs and the production time. Indeed, the two last parameters are essential to assess the relevance of each method in view of marketing

The french Chronic Kidney Disease-Renal Epidemiology and Information Network (CKD-REIN) cohort study : to better understand chronic kidney disease

International audienc

Risk profile, quality of life and care of patients with moderate and advanced CKD : The French CKD-REIN Cohort Study

Background: The French Chronic Kidney Disease-Renal Epidemiology and Information Network (CKD-REIN) cohort study was designed to investigate the determinants of prognosis and care of patients referred to nephrologists with moderate and advanced chronic kidney disease (CKD). We examined their baseline risk profile and experience.Methods: We collected bioclinical and patient-reported information from 3033 outpatients with CKD and estimated glomerular filtration rates (eGFRs) of 15-60 mL/min/1.73 m2 treated at 40 nationally representative public and private facilities.Results: The patients' median age was 69 (60-76) years, 65% were men, their mean eGFR was 33 mL/min/1.73 m2, 43% had diabetes, 24% had a history of acute kidney injury (AKI) and 57% had uncontrolled blood pressure (BP; >140/90 mmHg). Men had worse risk profiles than women and were more likely to be past or current smokers (73% versus 34%) and have cardiovascular disease (59% versus 42%), albuminuria >30 mg/mmol (or proteinuria > 50) (40% versus 30%) (all P < 0.001) and a higher median risk of end-stage renal disease within 5 years, predicted by the kidney failure risk equation {12% [interquartile range (IQR) 3-37%] versus 9% [3-31%], P = 0.008}. During the previous year, 60% of patients reported one-to-two nephrologist visits and four or more general practitioner visits; only 25% saw a dietician and 75% were prescribed five or more medications daily. Physical and mental quality of life (QoL) were poor, with scores <50/100.Conclusions: The CKD-REIN study highlights high-risk profiles of cohort members and identifies several priorities, including improving BP control and dietary counselling and increasing doctors' awareness of AKI, polypharmacy and QoL

Les ateliers-philo en contexte scolaire

Les discussions à visée philosophique (DVP) en école primaire et au collège relèvent d’une pratique qui a émergé aux Etats-Unis dans les années 1980 à l’initiative de Matthew Lipman (Lipman, Sharp & Oscanyan, 1980 ; voir Leleux, 2005). Dans un premier temps, les chercheurs ont investi les DVP au moyen de la technique des pré-tests et des post-tests pour mettre en évidence leurs effets sur les capacités cognitives et scolaires des élèves (Topping & Trickey, 2007 ; Higgins, Hall, Baumfield, & Moseley, 2005 ; Mortier, 2005 ; Millet & Tapper, 2012), sur leur propension à la coopération et au respect d’autrui (programme australien MCEETYA, 2008). Ce n’est que depuis peu et notamment dans le monde francophone, que de nouvelles recherches procèdent non plus via la passation de tests, mais par l’analyse de ce qui s’opère en DVP. C’est dans cette mouvance que les travaux restitués dans ce numéro se situent

Kidney Function Decline and Serious Adverse Drug Reactions in Patients With CKD

International audienceRationale & ObjectiveAdverse drug reactions (ADRs) are common in patients with chronic kidney disease (CKD). The impact of kidney function decline on serious ADR risk has been poorly investigated. We sought to comprehensively describe ADRs and assess the relationship between eGFR and serious ADR risk.Study DesignProspective cohort study.Setting & Participants3,033 participants in French Chronic Kidney Disease-Renal Epidemiology and Information Network (CKD-REIN) cohort study, a nationwide sample of nephrology outpatients with moderate-to-advanced CKD.PredictorsDemographic and biological data (including eGFR), medication prescriptions.OutcomesADRs (preventable or not) were prospectively identified from hospital discharge reports, medical records, and patient interviews. Expert pharmacologists used validated tools to adjudicate ADRs.Analytical ApproachRestricted cubic splines in fully adjusted cause-specific Cox proportional hazard models were used to evaluate the relationship between eGFR and the risk of serious ADRs (overall and by subtype).ResultsDuring a median follow-up period of 4.7 years, 360 patients experienced 488 serious ADRs. Kidney and urinary disorders (n=170) and hemorrhages (n=170) accounted for 70% of serious ADRs. The most common medications classes were antithrombotics and renin-angiotensin system inhibitors. The majority of those serious ADRs were associated with hospitalization (n=467), with 32 directly or indirectly associated with death, and 22 associated with life-threatening event. More than 27% of the 488 serious ADRs were preventable or potentially preventable. The eGFR is a major risk factor for serious ADRs. Risk of AKI was 2.2% higher and risk of bleeding ADRs were 8% higher for each 1 mL/min/1.73m2 lower baseline eGFR.LimitationsThe results cannot be extrapolated to patients who are not being followed up by a nephrologist.ConclusionsADRs constitute a major cause of hospitalization in CKD patients for whom lower eGFR level is a major risk factor

J Am Med Dir Assoc

Objectives Renin-angiotensin system inhibitors (RASi) are recommended for slowing chronic kidney disease (CKD) progression to kidney failure. Their effectiveness and tolerance as patients age remain uncertain because older patients have often been excluded from clinical trials. Design CKD-REIN cohort study. Setting and Participants We studied 2762 patients with CKD stages 3 and 4 and a clinical indication for RASi enrolled between 2013 and 2016 in 40 nephrology clinics nationally representative in France. Methods The primary outcome was the occurrence of kidney failure or death. The secondary outcomes were the occurrence of cardiovascular events and hospitalizations with acute kidney injury (AKI) or hyperkalemia. A propensity score analysis was performed. We used Cox models to estimate hazard ratios (HRs) for each outcome associated with RASi prescription and tested interactions with age. Results Patients' mean age was 67 years, including 841 (30%) aged 75 years and older; 2178 (79%) were prescribed RASi's. During a median follow-up of 4.6 years, 33% of patients reached kidney failure or died. RASi prescription was associated with a lower risk of kidney failure or death (HR 0.79, 95% CI 0.66, 0.95), an association not modified by age (P for interaction = .72). It was not significantly associated with cardiovascular events. During the first 3 years of follow-up, 14% of patients were hospitalized with AKI or hyperkalemia, but risk was not higher among those prescribed RASi's (HR 0.75, 95% CI 0.55-1.02) and age did not modify its effect (P for interaction = .28). Conclusions and Implications This study shows that aging does not appear to modify either RASi's beneficial effects on major CKD outcomes or their potential adverse effects