L'exercice de la Pluralité des mondes

no abstrac

L'exercice de la Pluralité des mondes

no abstrac

Stereoisomeric selection upon adsorption: A structural and optical study of curcuminoid derivatives on ultrathin films of KCl on Au(111) and on KCl(001) bulk

International audienc

Noncontact AFM and differential reflectance spectroscopy joint analyses of bis-pyrenyl thin films on bulk insulators: Relationship between structural and optical properties

International audienceThe combined characterization of structural and optical properties of organic interfaces adsorbed on inorganic solid substrates down to the molecular scale is crucial from a fundamental point of view, but also if one tackles efficient applied devices. In this work, a set of joint structural and optical analyses of self-assemblies of π-conjugated bis-pyrene derivatives upon adsorption on two alkali halides bulk insulators is reported. The structural analysis is performed by means of noncontact atomic force microscopy in ultrahigh vacuum either at room or at the liquid-nitrogen temperature with molecular resolution. The surface coverage ranges from the submonolayer (ML) regime up to 5 ML. In situ optical spectroscopy is performed by means of differential reflectance (DR) spectroscopy. A thorough fitting methodology of the DR spectra allows us to derive the complete dielectric function of the molecular adlayers treated in an anisotropic formalism, albeit restricted to an uniaxial approximation. Conclusions regarding the process of condensation of the molecules into H aggregates from its early stages up to the solid molecular phase are drawn. This work highlights three main reasons to bridge high-resolution structural and optical characterization of the molecular layers, which all point towards the necessity to constrain the fitting process, namely, (i) characterizing the growth mode of the molecules, (ii) identifying the structural order of the resulting assemblies, and (iii) discriminating their constitutive phases by means of molecular resolution imaging

Geographical variability of patient characteristics and treatment patterns affect outcomes for incident hemodialysis patients

Background: Geographical differences in disease prevalence and mortality have been described in the general population and in chronic kidney disease patients in Europe. In this secondary analysis of the Membrane Permeability Outcome (MPO) study, we addressed differences in patient and treatment patterns, and whether these affect patient outcomes. Methods: Participating countries were grouped according to geographical location; thus study centers in France, Greece, Italy, Portugal and Spain were allocated to southern Europe (n=499), and those in all other countries (Belgium, Germany, Poland and Sweden) to northern Europe (n=148). Descriptive analysis of patient and treatment patterns at study start, as well as survival analysis, was performed. Results: In patients from the northern European countries, a higher prevalence of diabetes mellitus and of cardiovascular disease was observed than in those from southern Europe (diabetes 35.1% vs. 21.0%, p=0.0007; cardiovascular disease 40.5% vs. 22.8%, p<0.0001). In northern Europe, 23% of patients started hemodialysis with a catheter for vascular access, while in southern European centers, only 13% did so (p=0.0042). Kaplan-Meier survival analysis revealed a lower probability for both all-cause and cardiovascular mortality in southern Europe (log-rank test p<0.001). In a Cox proportional hazards model, a higher mortality risk was estimated for the northern European patients after adjustment for age, sex, membrane permeability, comorbidity index and vascular access (hazard ratio = 1.831; 95% confidence interval, 1.282-2.615; p=0.0009). Conclusions: Our study patients from northern Europe showed a higher risk profile than those from southern Europe. However, only some of the factors can be modified in attempts to lower the mortality risk in this geographical area

Normal serum ApoB48 and red cells vitamin E concentrations after supplementation in a novel compound heterozygous case of abetalipoproteinemia

International audienceBACKGROUND AND AIMS: Abetalipoproteinemia (ABL) is a rare recessive monogenic disease due to MTTP (microsomal triglyceride transfer protein) mutations leading to the absence of plasma apoB-containing lipoproteins. Here we characterize a new ABL case with usual clinical phenotype, hypocholesterolemia, hypotriglyceridemia but normal serum apolipoprotein B48 (apoB48) and red blood cell vitamin E concentrations. METHODS: Histology and MTP activity measurements were performed on intestinal biopsies. Mutations in MTTP were identified by Sanger sequencing, quantitative digital droplet and long-range PCR. Functional consequences of the variants were studied in vitro using a minigene splicing assay, measurement of MTP activity and apoB48 secretion. RESULTS: Intestinal steatosis and the absence of measurable lipid transfer activity in intestinal protein extract supported the diagnosis of ABL. A novel MTTP c.1868G\textgreaterT variant inherited from the patient's father was identified. This variant gives rise to three mRNA transcripts: one normally spliced, found at a low frequency in intestinal biopsy, carrying the p.(Arg623Leu) missense variant, producing in vitro 65% of normal MTP activity and apoB48 secretion, and two abnormally spliced transcripts resulting in a non-functional MTP protein. Digital droplet PCR and long-range sequencing revealed a previously described c.1067+1217\₁141del allele inherited from the mother, removing exon 10. Thus, the patient is compound heterozygous for two dysfunctional MTTP alleles. The p.(Arg623Leu) variant may maintain residual secretion of apoB48. CONCLUSIONS: Complex cases of primary dyslipidemia require the use of a cascade of different methodologies to establish the diagnosis in patients with non-classical biological phenotypes and provide better knowledge on the regulation of lipid metabolism

Histoire et archéologie de la péninsule ibérique antique. Chronique II - 1973-1977

Etienne Robert, Fontaine Jacques, Coffyn André, Debord Pierre, Bost J.-P., Hiérnard Jean, Nony Daniel, Richard Jean-Claude, Rouillard Pierre, Richard Jean-Claude, Mayet F., Gorges J.-G., Lamour C., Le Roux Patrick, Fabre Georges, Tranoy Alain. Histoire et archéologie de la péninsule ibérique antique. Chronique II - 1973-1977. In: Revue des Études Anciennes. Tome 81, 1979, n°1-2. pp. 105-204

Low incidence of SARS-CoV-2, risk factors of mortality and the course of illness in the French national cohort of dialysis patients

International audienceThe aim of this study was to estimate the incidence of COVID-19 disease in the French national population of dialysis patients, their course of illness and to identify the risk factors associated with mortality. Our study included all patients on dialysis recorded in the French REIN Registry in April 2020. Clinical characteristics at last follow-up and the evolution of COVID-19 illness severity over time were recorded for diagnosed cases (either suspicious clinical symptoms, characteristic signs on the chest scan or a positive reverse transcription polymerase chain reaction) for SARS-CoV-2. A total of 1,621 infected patients were reported on the REIN registry from March 16th, 2020 to May 4th, 2020. Of these, 344 died. The prevalence of COVID-19 patients varied from less than 1% to 10% between regions. The probability of being a case was higher in males, patients with diabetes, those in need of assistance for transfer or treated at a self-care unit. Dialysis at home was associated with a lower probability of being infected as was being a smoker, a former smoker, having an active malignancy, or peripheral vascular disease. Mortality in diagnosed cases (21%) was associated with the same causes as in the general population. Higher age, hypoalbuminemia and the presence of an ischemic heart disease were statistically independently associated with a higher risk of death. Being treated at a selfcare unit was associated with a lower risk. Thus, our study showed a relatively low frequency of COVID-19 among dialysis patients contrary to what might have been assumed