Syndromic (phenotypic) diarrhea in early infancy

Syndromic diarrhea (SD), also known as phenotypic diarrhea (PD) or tricho-hepato-enteric syndrome (THE), is a congenital enteropathy presenting with early-onset of severe diarrhea requiring parenteral nutrition (PN). To date, no epidemiological data are available. The estimated prevalence is approximately 1/300,000–400,000 live births in Western Europe. Ethnic origin does not appear to be associated with SD. Infants are born small for gestational age and present with facial dysmorphism including prominent forehead and cheeks, broad nasal root and hypertelorism. Hairs are woolly, easily removed and poorly pigmented. Severe and persistent diarrhea starts within the first 6 months of life (≤ 1 month in most cases) and is accompanied by severe malabsorption leading to early and relentless protein energy malnutrition with failure to thrive. Liver disease affects about half of patients with extensive fibrosis or cirrhosis. There is currently no specific biochemical profile, though a functional T-cell immune deficiency with defective antibody production was reported. Microscopic analysis of the hair show twisted hair (pili torti), aniso- and poilkilotrichosis, and trichorrhexis nodosa. Histopathological analysis of small intestine biopsy shows non-specific villous atrophy with low or no mononuclear cell infiltration of the lamina propria, and no specific histological abnormalities involving the epithelium. The etiology remains unknown. The frequent association of the disorder with parental consanguinity and/or affected siblings suggests a genetic origin with an autosomal recessive mode of transmission. Early management consists of total PN. Some infants have a rather milder phenotype with partial PN dependency or require only enteral feeding. Prognosis of this syndrome is poor, but most patients now survive, and about half of the patients may be weaned from PN at adolescence, but experience failure to thrive and final short stature

Transcriptome profiling during a natural host-parasite interaction

BACKGROUND: Infection outcome in some coevolving host-pathogens is characterised by host-pathogen genetic interactions, where particular host genotypes are susceptible only to a subset of pathogen genotypes. To identify candidate genes responsible for the infection status of the host, we exposed a Daphnia magna host genotype to two bacterial strains of Pasteuria ramosa, one of which results in infection, while the other does not. At three time points (four, eight and 12 h) post pathogen exposure, we sequenced the complete transcriptome of the hosts using RNA-Seq (Illumina). RESULTS: We observed a rapid and transient response to pathogen treatment. Specifically, at the four-hour time point, eight genes were differentially expressed. At the eight-hour time point, a single gene was differentially expressed in the resistant combination only, and no genes were differentially expressed at the 12-h time point. CONCLUSIONS: We found that pathogen-associated transcriptional activity is greatest soon after exposure. Genome-wide resistant combinations were more likely to show upregulation of genes, while susceptible combinations were more likely to be downregulated, relative to controls. Our results also provide several novel candidate genes that may play a pivotal role in determining infection outcomes. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s12864-015-1838-0) contains supplementary material, which is available to authorized users

«Electrospray-mass spectrometry (ESI-MS): a window of opportunity to study β-cyclodextrin-metal complexes»

International audienceno abstrac

Airflow Characterization by Rayleigh-Mie Lidars

International audienceThis paper deals with lidar systems applied to airflow measurements. The properties of the two main light scattering processes, Rayleigh and Mie scattering, are presented and correlated to general but important rules for lidar design. The Rayleigh lidar developed at Onera for short-range wind speed measurements is also presented, and the Doppler analysis technique using Michelson fringe imagery is briefly discussed

Fast and wideband supercontinuum absorption spectroscopy in the mid-IR range

International audienceWe report on our new test bench dedicated to Supercontinuum Absorption Spectroscopy in the mid-infrared (3.3 µm). It delivers fast (<0.1 s) and wideband spectra (200 nm) at 0.8 cm-1 resolution. Gas concentrations are retrieved using a DOAS-inspired algorithm

Theoretical Investigation of Small Alkali Cation-Molecule Clusters: A Model Potential Approach

We present here a model potential study of the microsolvation of alkali cations M+ (M = Na, K, Rb, Cs) in various solvents (water, methanol, dimethyl ether (DME)). The potential energy surfaces (PES) are explored with the Monte Carlo growth method (MCGM) to find the most significant equilibrium structures of M+-(solvent)n clusters (n = 2, 4). The structures as well as the binding energies are favorably compared to the best ab initio calculations found in the literature and to experimental results. This good agreement is only obtained if we take into account the anisotropy of the polarizability tensor for the solvent molecule. Under these conditions, the atomic parameters included in our model potential framework are found to be transferable from water to methanol and DME. An analysis of the different physical components of the interaction energy shows that the only important n-body term for the description of these systems is the polarization one

Développements de LIDAR Doppler pour l’aéronautique

International audienceDetecting atmospheric hazards such as wake vortices, turbulences, wind shear or wind gusts would improve flight and airport traffic safety. Moreover, to face the current and future challenges of air traffic growth in terms of environment, safety and costs, one of the major challenges is to increase runway throughput by optimizing the distance separation between aircraft. These are some of the issues, among others, addressed by Doppler LIDARs. This powerful technique can provide remote air speed data and is being deployed on the ground or in flight. The paper presents some of the recent Doppler LIDAR developments at ONERA. Some insight into state-of-the-art technology is provided, as well as perspectives for future applications in aeronautics.La détection des dangers atmosphériques tels que les tourbillons de sillage, les cisaillements de vent ou les rafales améliorerait la sécurité du vol et du trafic aéroportuaire. De plus, pour faire face aux défis actuels et futurs de la croissance du trafic aérien en terme d’environnement, de sécurité et de coûts, un des principaux objectifs est d’accroître la cadence des atterrissages et des décollages en optimisant la distance de séparation entre avions. C’est entre autres à ce type de problème que le LIDAR Doppler se propose de répondre. Cette technique puissante permet de mesurer la vitesse de l’air à distance et peut être déployée au sol ou en vol.Ce papier expose certains des récents développements de LIDAR Doppler réalisés à l’ONERA. On y donne un aperçu de l’état de l’art de la technologie ainsi que des perspectives sur les futures applications en aéronautique