Accumulation of Immature Langerhans Cells in Human Lymph Nodes Draining Chronically Inflamed Skin

The coordinated migration and maturation of dendritic cells (DCs) such as intraepithelial Langerhans cells (LCs) is considered critical for T cell priming in response to inflammation in the periphery. However, little is known about the role of inflammatory mediators for LC maturation and recruitment to lymph nodes in vivo. Here we show in human dermatopathic lymphadenitis (DL), which features an expanded population of LCs in one draining lymph node associated with inflammatory lesions in its tributary skin area, that the Langerin/CD207+ LCs constitute a predominant population of immature DCs, which express CD1a, and CD68, but not CD83, CD86, and DC–lysosomal-associated membrane protein (LAMP)/CD208. Using LC-type cells generated in vitro in the presence of transforming growth factor (TGF)-β1, we further found that tumor necrosis factor (TNF)-α, as a prototype proinflammatory factor, and a variety of inflammatory stimuli and bacterial products, increase Langerin expression and Langerin dependent Birbeck granules formation in cell which nevertheless lack costimulatory molecules, DC–LAMP/CD208 and potent T cell stimulatory activity but express CCR7 and respond to the lymph node homing chemokines CCL19 and CCL21. This indicates that LC migration and maturation can be independently regulated events. We suggest that during DL, inflammatory stimuli in the skin increase the migration of LCs to the lymph node but without associated maturation. Immature LCs might regulate immune responses during chronic inflammation

ifCNV: A novel isolation-forest-based package to detect copy-number variations from various targeted NGS datasets

Copy-number variations (CNVs) are an essential component of genetic variation distributed across large parts of the human genome. CNV detection from next-generation sequencing data and artificial intelligence algorithms have progressed in recent years. However, only a few tools have taken advantage of machine-learning algorithms for CNV detection, and none propose using artificial intelligence to automatically detect probable CNV-positive samples. The most developed approach is to use a reference or normal dataset to compare with the samples of interest, and it is well known that selecting appropriate normal samples represents a challenging task that dramatically influences the precision of results in all CNV-detecting tools. With careful consideration of these issues, we propose here ifCNV, a new software based on isolation forests that creates its own reference, available in R and python with customizable parameters. ifCNV combines artificial intelligence using two isolation forests and a comprehensive scoring method to faithfully detect CNVs among various samples. It was validated using targeted next-generation sequencing (NGS) datasets from diverse origins (capture and amplicon, germline and somatic), and it exhibits high sensitivity, specificity, and accuracy. ifCNV is a publicly available open-source software (https://github.com/SimCab-CHU/ifCNV) that allows the detection of CNVs in many clinical situations

Can we use local climate zones for predicting malaria prevalence across sub-Saharan African cities?

Malaria burden is increasing in sub-Saharan cities because of rapid and uncontrolled urbanization. Yet very few studies have studied the interactions between urban environments and malaria. Additionally, no standardized urban land-use/land-cover has been defined for urban malaria studies. Here, we demonstrate the potential of local climate zones (LCZs) for modeling malaria prevalence rate (PfPR2-10) and studying malaria prevalence in urban settings across nine sub-Saharan African cities. Using a random forest classification algorithm over a set of 365 malaria surveys we: (i) identify a suitable set of covariates derived from open-source earth observations; and (ii) depict the best buffer size at which to aggregate them for modeling PfPR2-10. Our results demonstrate that geographical models can learn from LCZ over a set of cities and be transferred over a city of choice that has few or no malaria surveys. In particular, we find that urban areas systematically have lower PfPR2-10 (5%-30%) than rural areas (15%-40%). The PfPR2-10 urban-to-rural gradient is dependent on the climatic environment in which the city is located. Further, LCZs show that more open urban environments located close to wetlands have higher PfPR2-10. Informal settlements - represented by the LCZ 7 (lightweight lowrise) - have higher malaria prevalence than other densely built-up residential areas with a mean prevalence of 11.11%. Overall, we suggest the applicability of LCZs for more exploratory modeling in urban malaria studies. © 2020 The Author(s). Published by IOP Publishing Ltd.info:eu-repo/semantics/publishe

Composite Electrodes for Electrochemical Supercapacitors

Manganese dioxide nanofibers with length ranged from 0.1 to 1 μm and a diameter of about 4–6 nm were prepared by a chemical precipitation method. Composite electrodes for electrochemical supercapacitors were fabricated by impregnation of the manganese dioxide nanofibers and multiwalled carbon nanotubes (MWCNT) into porous Ni plaque current collectors. Obtained composite electrodes, containing 85% of manganese dioxide and 15 mass% of MWCNT, as a conductive additive, with total mass loading of 7–15 mg cm−2, showed a capacitive behavior in 0.5-M Na2SO4 solutions. The decrease in stirring time during precipitation of the nanofibers resulted in reduced agglomeration and higher specific capacitance (SC). The highest SC of 185 F g−1 was obtained at a scan rate of 2 mV s−1 for mass loading of 7 mg cm−2. The SC decreased with increasing scan rate and increasing electrode mass

Electrochemical study of H3PMo12 retention on Vulcan carbon grafted with NH2 and OH groups

In this work, we show a comparative study based on the effects of specific chemical functional groups (–OH, –NH2), grafted on Vulcan carbon (VC) with the incorporation of a specific polyoxometalate (POM), PMo12 (H3PMo12O40), to improve electrochemical performance. We observed a decrease in the specific surface area of the grafted matrices (VC-OH and VC-NH2) [1], and the same trend was observed for PMo12 (POM) incorporation. Our electrochemical studies showed low concentrations of POM in unmodified VCs and higher POM concentrations for grafted matrices (VC-OH and VC-NH2) after 500 voltammetric cycles, especially for the VC grafted with –OH groups (VC-OH-POM). Mechanisms have been proposed for POM interaction with the grafted groups in carbon, emphasizing the role of aqueous medium and redox activity of POM. Cyclic voltammograms suggested the POM anchoring through –OH groups with a strong interaction as a covalent bond, resulting in a surface coverage of 1.66 × 10−11 mol cm−2. Surface modifications could be extrapolated to other carbons, and the materials could be employed for different potential applications such as photocatalysis, amperometric sensors, fuel cells, and supercapacitors.Fil: Cuentas Gallegos, Ana Karina. Universidad Nacional Autónoma de México; México. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: López Cortina, S.. Universidad Autonoma de Nuevo Leon; MéxicoFil: Brousse, T.. Université de Nantes. Institut Des Materiaux Jean Rouxel; FranciaFil: Pacheco Catalán, D.. Centro de Investigación Científica de Yucatán; MéxicoFil: Fuentes Quezada, Eduardo. Centro de Investigación y Desarrollo Tecnológico en Electroquímica; México. Universidad Nacional Autónoma de México; México. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Mosqueda, H.. Universidad Autonoma de Nuevo Leon; MéxicoFil: Orozco Gamboa, G.. Centro de Investigación y Desarrollo Tecnológico en Electroquímica; Méxic

Cytophagic histiocytic panniculitis: is it a macrophage activation syndrome in situ?

International audiencepas de résum

Associations between environmental factors and hospital admissions for sickle cell disease

Sickle cell disease (SCD) is an increasing global health burden. This inherited disease is characterised by a remarkable phenotypic heterogeneity, which can only partly be explained by genetic factors. Environmental factors are likely to play an important role but studies of their impact on disease severity are limited and their results are often inconsistent. This study investigated associations between a range of environmental factors and hospital admissions of young patients with SCD in London and in Paris between 2008 and 2012. Specific analyses were conducted for sub-groups of patients with different genotypes and for the main reasons of admissions. Generalized additive models and distributed lag non-linear models were used to assess the magnitude of the associations and to calculate relative risks. Some environmental factors significantly influence the numbers of hospital admissions of children with SCD, although the associations identified are complicated. Our study suggests that meteorological factors are more likely to be associated with hospital admissions for SCD than air pollutants. It confirms previous reports of risks associated with wind speed (RR: 1.06/SD [95% confidence interval (CI): 1.00-1.12]) and also with rainfall (RR: 1.06/SD [95%CI: 1.01-1.12]). Maximum atmospheric pressure was found to be a protective factor (RR: 0.93/SD [95%CI: 0.88-0.99]). Weak or no associations were found with temperature. Divergent associations were identified for different genotypes or reasons of admissions, which could partly explain the lack of consistency in earlier studies. Advice to patients with SCD usually includes avoiding a range of environmental conditions that are believed to trigger acute complications, including extreme temperatures and high altitudes. Scientific evidence to support such advice is limited and sometimes confusing. This study shows that environmental factors do explain some of the variations in rates of admission to hospital with acute symptoms in SCD, but the associations are complex, and likely to be specific to different environments and the individual's exposure to them. Furthermore, this study highlights the need for prospective studies with large numbers of patients and standardised protocols across Europe

Effect of the COVID-19 pandemic on the psychotropic drug consumption

International audienceImportance Although the COVID-19 pandemic has had a negative impact on mental health, there is no comprehensive longitudinal study of the entire population of a country without selection bias. Objective The objective of this study was to evaluate the prescription of psychotropic drugs during the COVID-19 pandemic, using data from the French national health data system (SNDS). Design, settings, and participants Prescriptions for psychotropic drugs (antidepressants, anxiolytics, hypnotics, and antipsychotics) from 1 January 2015 to 30 September 2021 were collected from administrative data provided by the SNDS. This database includes more than 99% of the French population, i.e., 67 million people. The data were analyzed using an interrupted time series analysis (ITSA) model. Main outcomes and measures Consumption of psychotropic drugs was aggregated in months and expressed in number of boxes per thousand inhabitants. Results During the study period, more than 1.3 billion boxes of psychotropic medications were dispensed. Comparison of psychotropic drug dispensing before and after the pandemic showed a relative increase of 0.76 (95 CI 0.57 to 0.95, p <0.001) boxes per month per thousand inhabitants, all classes of psychotropic drugs combined. Three classes saw their consumption increase in an almost similar proportion, respectively, by 0.23 (0.15 to 0.32, p <0.001) boxes for antidepressants, 0.27 (0.20 to 0.34, p <0.001) boxes for anxiolytics and 0.23 (0.17 to 0.30, p <0.001) boxes for hypnotics. The change in antipsychotic consumption was very small, with an increase of 0.04 boxes (0.02 to 0.06, p = 0.001) per month per thousand population. Conclusion and relevance The COVID-19 pandemic had led to an increase in the consumption of psychotropic drugs, confirming the significant impact of the pandemic on the mental health of the general population