Infections néonatales à entérovirus en France en 2012 Soudée, S.; Schuffenecker, I.; Aberchih, J. ...
Archives de pédiatrie : organe officiel de la Société française de pédiatrie,
September 2014, Letnik:
21, Številka:
9
Journal Article
Recenzirano
Les entérovirus (EV) sont parmi les virus les plus fréquemment rencontrés chez l’homme. Un tiers des infections à EV touche des enfants de moins de 1 an. Les manifestations cliniques sont extrêmement ...variables allant d’une fièvre isolée à la défaillance multiviscérale pouvant associer une hépatite avec troubles de la coagulation, une myocardite ou une encéphalite. À partir de la base de données du Centre national de référence des infections à EV de Lyon, nous avons étudié les données démographiques, cliniques et biologiques des enfants de moins de 1 mois hospitalisés en 2012 en France pour infection à EV. Deux sous-groupes ont été constitués en fonction de la date de début des symptômes : les infections précoces ayant débuté jusqu’à 8jours de vie (j8) et les infections tardives ayant débuté strictement après j8. Cent vingt dossiers ont été analysés. Jusqu’à j8, les enfants présentant une infection sévère étaient nés plus prématurément avec un plus faible poids de naissance et les coxsackies CV-B4 et l’échovirus E-11 étaient les plus représentés. Les critères de gravité clinique étaient l’atteinte hépatique (73 % dans les formes sévères jusqu’à j8) et hématologique (82 % de thrombopénie et 64 % de coagulation intravasculaire disséminée dans les formes sévères jusqu’à j8). Ces résultats suggèrent une fenêtre de vulnérabilité des infections à EV chez les nouveau-nés infectés jusqu’à j8, avec un tropisme hépatique du virus dans les infections sévères. Nous recommandons la réalisation d’un sérotypage systématique des infections à EV néonatales ainsi que la surveillance biologique de la fonction hépatique afin de repérer précocement les enfants à risque de dégradation clinique.
Enteroviruses (EVs) are among the most common viruses infecting humans. One-third of EV infections affect children under 1year of age. Neonatal EV infections lead to a wide range of clinical manifestations, from mild febrile illness to severe, potentially fatal sepsis-like conditions with multiorgan failure. EV detections by serotype are reported by the National Reference Centre for EV Infections Lyon on a monthly basis. Demographic, clinical, and biological data were also collected in neonates hospitalized in 2012 for EV infection. Two subgroups were identified according to the beginning of symptoms: until 8 days of life (D8) or strictly after D8. There were 120 neonatal EV infections. Before D8, children with severe infection were born more prematurely with a low birth weight. The EVs most commonly detected in neonates were CV-B4 and E-11. Risk factors for severe EV infections included liver (73% before D8) and hematological damage (thrombocytopenia, 82%; coagulopathy, 64% before D8). This study suggests that systematic serotyping of neonatal EV infections and biological monitoring of liver function could be useful for early identification of children at high risk of clinical severity and fatality.
The future ExoMars rover mission (ESA/Roscosmos), to be launched in 2018, will investigate the habitability of the Martian surface and near subsurface, and search for traces of past life in the form ...of textural biosignatures and organic molecules. In support of this mission, a selection of relevant Mars analogue materials has been characterised and stored in the International Space Analogue Rockstore (ISAR), hosted in Orléans, France. Two ISAR samples were analysed by prototypes of the ExoMars rover instruments used for petrographic study. The objective was to determine whether a full interpretation of the rocks could be achieved on the basis of the data obtained by the ExoMars visible-IR imager and spectrometer (MicrOmega), the close-up imager (CLUPI), the drill infrared spectrometer (Ma_Miss) and the Raman spectrometer (RLS), first separately then in their entirety. In order to not influence the initial instrumental interpretation, the samples were sent to the different teams without any additional information. This first step was called the “Blind Test” phase. The data obtained by the instruments were then complemented with photography of the relevant outcrops (as would be available during the ExoMars mission) before being presented to two geologists tasked with the interpretation. The context data and photography of the outcrops and of the samples were sufficient for the geologists to identify the rocks. This initial identification was crucial for the subsequent, iterative interpretation of the spectroscopic data. The data from the different spectrometers was, thus, cross-calibrated against the photographic interpretations and against each other. In this way, important mineralogical details, such as evidence of aqueous alteration of the rocks, provided relevant information concerning potential habitable conditions. The final conclusion from this test is that, when processed together, the ExoMars payload instruments produce complementary data allowing reliable interpretation of the geological context and potential for habitable environments. This background information is fundamental for the analysis and interpretation of organics in the processed Martian rocks.
•First test of the ExoMars payload.•Test with will characterised Mars analogue samples.•Collaborative exercise with different ExoMars teams.•Proposed protocol to increase the scientific return of the ExoMars mission.
Approximate models (proxies) can be employed to reduce the computational costs of estimating uncertainty. The price to pay is that the approximations introduced by the proxy model can lead to a ...biased estimation. To avoid this problem and ensure a reliable uncertainty quantification, we propose to combine functional data analysis and machine learning to build error models that allow us to obtain an accurate prediction of the exact response without solving the exact model for all realizations. We build the relationship between proxy and exact model on a learning set of geostatistical realizations for which both exact and approximate solvers are run. Functional principal components analysis (FPCA) is used to investigate the variability in the two sets of curves and reduce the dimensionality of the problem while maximizing the retained information. Once obtained, the error model can be used to predict the exact response of any realization on the basis of the sole proxy response. This methodology is purpose‐oriented as the error model is constructed directly for the quantity of interest, rather than for the state of the system. Also, the dimensionality reduction performed by FPCA allows a diagnostic of the quality of the error model to assess the informativeness of the learning set and the fidelity of the proxy to the exact model. The possibility of obtaining a prediction of the exact response for any newly generated realization suggests that the methodology can be effectively used beyond the context of uncertainty quantification, in particular for Bayesian inference and optimization.
Key Points:
Use an error model to predict exact response from the proxy response
Investigate the proxy relevance for the quantity of interest
Accelerate uncertainty quantification
In recent years, metagenomic Next-Generation Sequencing (mNGS) has increasingly been used for an accurate assumption-free virological diagnosis. However, the systematic workflow evaluation on ...clinical respiratory samples and implementation of quality controls (QCs) is still lacking.
A total of 3 QCs were implemented and processed through the whole mNGS workflow: a no-template-control to evaluate contamination issues during the process; an internal and an external QC to check the integrity of the reagents, equipment, the presence of inhibitors, and to allow the validation of results for each sample. The workflow was then evaluated on 37 clinical respiratory samples from patients with acute respiratory infections previously tested for a broad panel of viruses using semi-quantitative real-time PCR assays (28 positive samples including 6 multiple viral infections; 9 negative samples). Selected specimens included nasopharyngeal swabs (n = 20), aspirates (n = 10), or sputums (n = 7).
The optimal spiking level of the internal QC was first determined in order to be sufficiently detected without overconsumption of sequencing reads. According to QC validation criteria, mNGS results were validated for 34/37 selected samples. For valid samples, viral genotypes were accurately determined for 36/36 viruses detected with PCR (viral genome coverage ranged from 0.6 to 100%, median = 67.7%). This mNGS workflow allowed the detection of DNA and RNA viruses up to a semi-quantitative PCR Ct value of 36. The six multiple viral infections involving 2 to 4 viruses were also fully characterized. A strong correlation between results of mNGS and real-time PCR was obtained for each type of viral genome (R
ranged from 0.72 for linear single-stranded (ss) RNA viruses to 0.98 for linear ssDNA viruses).
Although the potential of mNGS technology is very promising, further evaluation studies are urgently needed for its routine clinical use within a reasonable timeframe. The approach described herein is crucial to bring standardization and to ensure the quality of the generated sequences in clinical setting. We provide an easy-to-use single protocol successfully evaluated for the characterization of a broad and representative panel of DNA and RNA respiratory viruses in various types of clinical samples.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
We present new results from the mapping of lunar photometric function parameters using images acquired by the spacecraft SMART-1 (European Space Agency). The source data for selected lunar areas ...imaged by the AMIE camera of SMART-1 and the data processing are described. We interpret the behavior of photometric function in terms of lunar regolith properties. Our study reveals photometric anomalies on both small (sub-kilometer) and large (tens of kilometers) scales. We found the regolith mesoscale roughness of lunar swirls to be similar in Mare Marginis, Mare Ingenii, and the surrounding terrains. Unique photometric properties related to peculiarities of the millimeter-scale regolith structure for the Reiner Gamma swirl are confirmed. We identified several impact craters of subkilometer sizes as the source of photometric anomalies created by an increase in mesoscale roughness within the proximal crater ejecta zones. The extended ray systems reveal differences in the photometric properties between proximal and distant ejecta blankets. Basaltic lava flows within Mare Imbrium and Oceanus Procellarum indicate higher regolith porosity for the redder soils due to differences in the chemical composition of lavas.
Data on herpes simplex virus (HSV) polymorphism as well as acyclovir (ACV) and foscarnet (FOS) resistance mutations are not exhaustive and may hinder accurate diagnosis by next-generation sequencing ...(NGS). Here, we report novel UL23 and UL30 substitutions for HSV1 and HSV2 identified in immunocompromised patients treated for hematological malignancies during the last 6 years of HSV resistance surveillance at the University Hospital of Lyon. For HSV1, 35 novel UL23 substitutions and 52 novel UL30 substitutions were identified. For HSV2, 2 novel UL23 substitutions and 12 novel UL30 substitutions were identified. These results allow to complete the database of HSV1 and HSV2 substitutions, related either to polymorphism or to ACV and FOS resistance.
•Exploration of UL23 and UL30 genes involved in drug activities is necessary for reliable genotypic detection.•For HSV1, we report 35 novel UL23 substitutions and 52 novel UL30 substitutions.•For HSV2, we report 2 novel UL23 substitutions and 12 novel UL30 substitutions.•61 novel substitutions could be related to polymorphism.•4 novel substitutions could be related to drug resistance.
We investigate the light-scattering properties of the lunar mare areas. A large photometric dataset was extracted from images taken by the AMIE camera on board the SMART-1 spacecraft. Inter-particle ...shadowing effects in the regolith are modelled using ray-tracing simulations, and then a phase function is fit to the data using Bayesian techniques and Markov chain Monte Carlo. Additionally, the data are fit with phase functions computed from radiative-transfer coherent-backscatter (RT-CB) simulations. The results indicate that the lunar photometry, including both the opposition effect and azimuthal effects, can be explained well with a combination of inter-particle shadowing and coherent backscattering. Our results produce loose constraints on the mare physical properties. The RT-CB results indicate that the scattering volume element is optically thick. In both the Bayesian analysis and the RT-CB fit, models with lower packing density and/or higher surface roughness always produce better fits to the data than densely packed, smoother ones.
A novel shadowing and coherent-backscattering model is utilized in the analysis of the single-scattering albedos and phase functions, local surface roughness, and regolith porosity of specific lunar ...mare regions imaged by the AMIE camera (Advanced Moon micro-Imager Experiment) onboard ESA SMART-1 mission. Shadowing due to the regolith particles is accounted via ray-tracing computations for densely-packed particulate media with a fractional-Brownian-motion interface with free space. The shadowing modeling allows us to derive the scattering phase function for a ~100-μm volume element of the lunar mare regolith. The volume-element phase function is explained by coherent-backscattering modeling, where the fundamental single scatterers are the wavelength-scale particle inhomogeneities or the smallest fraction of the particles on the lunar surface. The phase function of the fundamental scatterers is expressed as a sum of two Henyey-Greenstein terms, accounting for increased backward scattering as well as increased forward scattering. Based on the modeling of the AMIE lunar photometry, we conclude that most of the lunar mare opposition effect is caused by coherent backscattering within volume elements comparable in size to typical lunar particles, with only a small contribution from shadowing effects.
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