Éditeur(s) : HAL CCSD Public Library of Science
Résumé : International audience
Diagnosis of toxoplasmic encephalitis (TE) in patients with AIDS is not straightforward because clinicians rely initially on an empiric diagnosis based on clinical and radiographic improvement to specific anti-Toxoplasma gondii therapy. There is therefore a need for biological tools to improve the diagnosis of TE, especially in tropical areas where this diagnosis is likely to be underestimated. The use of PCR testing in blood samples for the diagnosis of TE has been limited by its poor sensitivity in the studies conducted in Europe. In tropical South America, the results of PCR sensitivity in blood samples were controversial. Considering that T. gondii strains from tropical South America have substantial genetic and pathogenic differences with those from USA and Europe, it is therefore important to re-evaluate the performance of the PCR assay in blood samples for the diagnosis of TE in AIDS patients from this region. Our results showed that the only interest of PCR would be in the most severe forms of TE with altered consciousness because PCR is more likely to be positive. We also provided important genotyping data on T. gondii strains isolated in human cases of toxoplasmosis in the Caribbean and in South America.
ISSN: 1935-2727

hal-01503761
https://hal-unilim.archives-ouvertes.fr/hal-01503761
https://hal-unilim.archives-ouvertes.fr/hal-01503761/document
https://hal-unilim.archives-ouvertes.fr/hal-01503761/file/journal.pntd.0004790.pdf
DOI : 10.1371/journal.pntd.0004790

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
ISSN: 0043-1648

hal-01679411
https://hal.univ-antilles.fr/hal-01679411
DOI : 10.1016/j.wear.2004.11.019

Éditeur(s) : HAL CCSD BioMed Central
Résumé : International audience
Background: HCV treatment uptake has drastically increased in HIV-HCV coinfected patients in France since direct-acting antiviral (DAA) treatment approval, resulting in HCV cure in 63% of all HIV-HCV patients by the end of 2015. We investigated the impact of scaling-up DAA on HCV prevalence in the whole HIV population and in various risk groups over the next 10 years in France using a transmission dynamic compartmental model.Methods: The model was based on epidemiological data from the French Dat’AIDS cohort. Eight risk groups wereconsidered, including high-risk (HR) and low-risk (LR) men who have sex with men (MSM) and male/female heterosexuals,intra-venous drug users, or patients from other risk groups. The model was calibrated on prevalence and incidence dataobserved in the cohort between 2012 and 2015.Results: On January 1, 2016, 156,811 patients were registered as infected with HIV in France (24,900 undiagnosedpatients) of whom 7938 (5.1%) had detectable HCV-RNA (722 undiagnosed patients). Assuming a treatmentcoverage (TC) rate of 30%/year (i.e., the observed rate in 2015), model projections showed that HCV prevalenceamong HIV patients is expected to drop to 0.81% in 2026. Sub-analyses showed a similar decrease of HIV-HCVprevalence in most risk groups, including LR MSM. Due to higher infection and reinfection rates, predicted prevalencein HR MSM remained stable from 6.96% in 2016 to 6.34% in 2026. Increasing annual TC rate in HR MSM to 50/70%would decrease HCV prevalence in this group to 2.35/1.25% in 2026. With a 30% TC rate, undiagnosed patients wouldaccount for 34% of HCV infections in 2026.Conclusions: Our model suggests that DAA could nearly eliminate coinfection in France within 10 years for most riskgroups, including LR MSM. Elimination in HR MSM will require increased TC.
ISSN: 1741-7015

Droits : info:eu-repo/semantics/OpenAccess
inserm-01685739
http://www.hal.inserm.fr/inserm-01685739
http://www.hal.inserm.fr/inserm-01685739/document
http://www.hal.inserm.fr/inserm-01685739/file/2017%2C%20Virlogeux%20-%20Modeling%20HIV-HCV%20coinfection.pdf
DOI : 10.1186/s12916-017-0979-1

Éditeur(s) : HAL CCSD Editions Quae
Résumé :  
absent
De l'observation des écosystèmes forestiers à l'information sur la forêt
Paris, France

hal-01032065
https://hal.archives-ouvertes.fr/hal-01032065

Éditeur(s) : Pergamon-elsevier Science Ltd
Résumé : Society's needs for a network of in situ ocean observing systems cross many areas of earth and marine science. Here we review the science themes that benefit from data supplied from ocean observatories. Understanding from existing studies is fragmented to the extent that it lacks the coherent long-term monitoring needed to address questions at the scales essential to understand climate change and improve geo-hazard early warning. Data sets from the deep sea are particularly rare with long-term data available from only a few locations worldwide. These science areas have impacts on societal health and well-being and our awareness of ocean function in a shifting climate. Substantial efforts are underway to realise a network of open-ocean observatories around European Seas that will operate over multiple decades. Some systems are already collecting high-resolution data from surface, water column, seafloor, and sub-seafloor sensors linked to shore by satellite or cable connection in real or near-real time, along with samples and other data collected in a delayed mode. We expect that such observatories will contribute to answering major ocean science questions including: How can monitoring of factors such as seismic activity, pore fluid chemistry and pressure, and gas hydrate stability improve seismic, slope failure, and tsunami warning? What aspects of physical oceanography, biogeochemical cycling, and ecosystems will be most sensitive to climatic and anthropogenic change? What are natural versus anthropogenic changes? Most fundamentally, how are marine processes that occur at differing scales related? The development of ocean observatories provides a substantial opportunity for ocean science to evolve in Europe. Here we also describe some basic attributes of network design. Observatory networks provide the means to coordinate and integrate the collection of standardised data capable of bridging measurement scales across a dispersed area in European Seas adding needed certainty to estimates of future oceanic conditions. Observatory data can be analysed along with other data such as those from satellites, drifting floats, autonomous underwater vehicles, model analysis, and the known distribution and abundances of marine fauna in order to address some of the questions posed above. Standardised methods for information management are also becoming established to ensure better accessibility and traceability of these data sets and ultimately to increase their use for societal benefit. The connection of ocean observatory effort into larger frameworks including the Global Earth Observation System of Systems (GEOSS) and the Global Monitoring of Environment and Security (GMES) is integral to its success. It is in a greater integrated framework that the full potential of the component systems will be realised. Crown Copyright (C) 2011 Published by Elsevier Ltd. All rights reserved.
Progress In Oceanography (0079-6611) (Pergamon-elsevier Science Ltd), 2011-10 , Vol. 91 , N. 1 , P. 1-33

Droits : 2011 Published by Elsevier Ltd. All rights reserved.
http://archimer.ifremer.fr/doc/00044/15557/15923.pdf
DOI:10.1016/j.pocean.2011.05.001
http://archimer.ifremer.fr/doc/00044/15557/

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
ISSN: 0012-8252

hal-01671832
https://hal-univ-rochelle.archives-ouvertes.fr/hal-01671832
DOI : 10.1016/j.earscirev.2016.12.005

Éditeur(s) : HAL CCSD Elsevier
Résumé : Vegetation phenology is the study of the timing of seasonal events that are considered to be the result of adaptive responses to climate variations on short and long time scales. In the field of remote sensing of vegetation phenology, phenological metrics are derived from time series of optical data. For that purpose, considerable effort has been specifically focused on developing noise reduction and cloud-contaminated data removal techniques to improve the quality of remotely-sensed time series. Comparative studies between time series composed of satellite data acquired under clear and cloudy conditions and from radiometric data obtained with high accuracy from ground-based measurements constitute a direct and effective way to assess the operational use and limitations of remote sensing for predicting the main plant phenological events. In the present paper, we sought to explicitly evaluate the potential use of MODerate resolution Imaging Spectroradiometer (MODIS) remote sensing data for monitoring the seasonal dynamics of different types of vegetation cover that are representative of the major terrestrial biomes, including temperate deciduous forests, evergreen forests, African savannah, and crops. After cloud screening and filtering, we compared the temporal patterns and phenological metrics derived from in situ NDVI time series and from MODIS daily and 16-composite products. We also evaluated the effects of residual noise and the influence of data gaps in MODIS NDVI time series on the identification of the most relevant metrics for vegetation phenology monitoring. The results show that the inflexion points of a model fitted to a MODIS NDVI time series allow accurate estimates of the onset of greenness in the spring and the onset of yellowing in the autumn in deciduous forests (RMSE <= one week). Phenological metrics identical to those provided with the MODIS Global Vegetation Phenology product (MDC12Q2) are less robust to data gaps, and they can be subject to large biases of approximately two weeks or more during the autumn phenological transitions. In the evergreen forests, in situ NDVI time series describe the phenology with high fidelity despite small temporal changes in the canopy foliage. However, MODIS is unable to provide consistent phenological patterns. In crops and savannah, MODIS NDVI time series reproduce the general temporal patterns of phenology, but significant discrepancies appear between MODIS and ground-based NDVI time series during very localized periods of time depending on the weather conditions and spatial heterogeneity within the MODIS pixel. In the rainforest, the temporal pattern exhibited by a MODIS 16-day composite NDVI time series is more likely due to a pattern of noise in the NDVI data structure according to both rainy and dry seasons rather than to phenological changes. More investigations are needed, but in all cases, this result leads us to conclude that MODIS time series in tropical rainforests should be interpreted with great caution. (C) 2013 Elsevier Inc. All rights reserved.
ISSN: 0034-4257

hal-01032407
https://hal.archives-ouvertes.fr/hal-01032407
DOI : 10.1016/j.rse.2013.01.010

Éditeur(s) : HAL CCSD Elsevier
Résumé : absent
ISSN: 0034-4257

hal-01019844
https://hal.archives-ouvertes.fr/hal-01019844
DOI : 10.1016/j.rse.2012.03.012

Éditeur(s) : HAL CCSD BMJ Publishing Group
Résumé : International audience
BACKGROUND: Mutations in the leucine-rich-repeat kinase 2 (LRRK2) gene have been identified in families with autosomal dominant Parkinson's disease (ADPD), the most common of which is the p.G2019S substitution that has been found at varying frequencies worldwide. Because of the size of the LRRK2 gene, few studies have analysed the entire gene in large series of ADPD families. METHODS: We performed extensive mutation analyses of all 51 coding exons of the LRRK2 gene in index cases from 226 Parkinson's disease families compatible with autosomal dominant inheritance, mostly from France (n = 182) and North Africa (n = 14). RESULTS: We found 79 sequence variants, 29 of which were novel. Eight potentially or proven pathogenic mutations were found in 22 probands (9.7%). There were four novel amino acid substitutions that are potentially pathogenic (p.S52F, p.N363S, p.I810V, p.R1325Q) and two novel variants, p.H1216R and p.T1410M, that are probably not causative. The common p.G2019S mutation was identified in 13 probands (5.8%) including six from North Africa (43%). The known heterozygous p.R1441H and p.I1371V mutations were found in two probands each, and the p.E334K variant was identified in one single patient. Most potentially or proven pathogenic mutations were located in the functional domains of the Lrrk2 protein. CONCLUSION: This study leads us to conclude that LRRK2 mutations are a common cause of autosomal dominant Parkinson's disease in Europe and North Africa.
ISSN: 0022-2593

inserm-00529272
http://www.hal.inserm.fr/inserm-00529272
DOI : 10.1136/jmg.2008.062612
PUBMED : 19357115

Éditeur(s) : HAL CCSD Elsevier Masson
Résumé : National audience
Objectifs Évaluer les connaissances des médecins généralistes et des pharmaciens d'officine en matière de dopage sportif, Populations et méthodes Deux études descriptives transversales par questionnaire anonyme ont été menées en 2006 et 2009 respectivement chez 280 pharmaciens et 992 médecins. Résultats Ils estiment que la plupart des records sont battus grâce au dopage et que les champions y recourent. Selon eux, les sports les plus touchés sont le cyclisme, l'athlétisme, le football, l'haltérophilie et la natation. Ils méconnaissent la liste des produits interdits. Pour eux, les personnes proches des sportifs et Internet sont les principales sources d'approvisionnement en dopants. Seuls 42 % des médecins et 35 % des pharmaciens pensent informer un patient sportif sur les produits pouvant positiver un contrôle antidopage. On note que 51,5 % des médecins ne connaissent pas les autorisations d'usage à des fins thérapeutiques et 90 % ignorent l'existence des antennes médicales de prévention du dopage. Ils déclarent ne pas avoir reçu d'enseignement universitaire spécifique sur le dopage et s'estiment mal informés. Conclusion Les médecins généralistes et les pharmaciens d'officine ne semblent pas disposer de connaissances suffisantes pour assurer leurs missions et pour prendre conscience de leurs responsabilités dans la lutte antidopage.
ISSN: 0765-1597

hal-01010769
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01010769
DOI : 10.1016/j.scispo.2013.10.004

Éditeur(s) : HAL CCSD
Résumé : International audience
Up-to-date estimates of the health outcomes of preterm children are needed for assessing perinatal care, informing parents, making decisions about care, and providing evidence for clinical guidelines. To determine survival and neonatal morbidity of infants born from 22 through 34 completed weeks' gestation in France in 2011 and compare these outcomes with a comparable cohort in 1997. The EPIPAGE-2 study is a national, prospective, population-based cohort study conducted in all maternity and neonatal units in France in 2011. A total of 2205 births (stillbirths and live births) and terminations of pregnancy at 22 through 26 weeks' gestation, 3257 at 27 through 31 weeks, and 1234 at 32 through 34 weeks were studied. Cohort data were collected from January 1 through December 31, 1997, and from March 28 through December 31, 2011. Analyses for 1997 were run for the entire year and then separately for April to December; the rates for survival and morbidities did not differ. Data are therefore presented for the whole year in 1997 and the 8-month and 6-month periods in 2011. Survival to discharge and survival without any of the following adverse outcomes: grade III or IV intraventricular hemorrhage, cystic periventricular leukomalacia, severe bronchopulmonary dysplasia, retinopathy of prematurity (stage 3 or higher), or necrotizing enterocolitis (stages 2-3). A total of 0.7% of infants born before 24 weeks' gestation survived to discharge: 31.2% of those born at 24 weeks, 59.1% at 25 weeks, and 75.3% at 26 weeks. Survival rates were 93.6% at 27 through 31 weeks and 98.9% at 32 through 34 weeks. Infants discharged home without severe neonatal morbidity represented 0% at 23 weeks, 11.6% at 24 weeks, 30.0% at 25 weeks, 47.5% at 26 weeks, 81.3% at 27 through 31 weeks, and 96.8% at 32 through 34 weeks. Compared with 1997, the proportion of infants surviving without severe morbidity in 2011 increased by 14.4% (P < .001) at 25 through 29 weeks and 6% (P < .001) at 30 through 31 weeks but did not change appreciably for those born at less than 25 weeks. The rates of antenatal corticosteroid use, induced preterm deliveries, cesarean deliveries, and surfactant use increased significantly in all gestational-age groups, except at 22 through 23 weeks. The substantial improvement in survival in France for newborns born at 25 through 31 weeks' gestation was accompanied by an important reduction in severe morbidity, but survival remained rare before 25 weeks. Although improvement in survival at extremely low gestational age may be possible, its effect on long-term outcomes requires further studies. The long-term results of the EPIPAGE-2 study will be informative in this regard.
ISSN: 2168-6211

hal-01258705
http://hal.univ-brest.fr/hal-01258705
PUBMED : 25621457
DOI : 10.1001/jamapediatrics.2014.3351

Éditeur(s) : HAL CCSD Météo et Climat
Résumé : International audience
D'initiative française, le projet international HyMeX a pour objectif d'améliorer la compréhension du cycle de l'eau en Méditerranée, de sa variabilité, de l'échelle de l'événement météorologique aux échelles saisonnières et interannuelles, et de ses caractéristiques sur une décennie, dans un contexte de changement global. Le projet est motivé par le rôle déterminant des processus de mésoéchelle, couplés entre l'atmosphère, la mer et la terre, sur la variabilité du système climatique et sur le déclenchement d'événements hydrométéorologiques extrêmes (précipitations et inondations, vents forts et convection océanique, canicules et sécheresses). Le projet vise enfin à évaluer les conséquences de ces événements extrêmes sur la vulnérabilité sociale et économique de cette région et sa capacité d'adaptation.
ISSN: 0026-1181

hal-00828758
https://hal.archives-ouvertes.fr/hal-00828758
https://hal.archives-ouvertes.fr/hal-00828758/document
https://hal.archives-ouvertes.fr/hal-00828758/file/meteo_2013_80_23%20%281%29.pdf
DOI : 10.4267/2042/48792

Éditeur(s) : HAL CCSD
Résumé : International audience
In boundary lubrication regime, friction reduction and antiwear processes are associated to the presence of additives in the lubricating oils or greases. These processes are due to the formation of protective tribofilms resulting from chemical reactions between the additives and the sliding surfaces, in the physico-chemical conditions of the sliding contact. Conventional antiwear additives mainly consist of transition metal organo phosphate or thiophosphates which present a remarkable efficiency in the case of contacts between ferrous alloys. In the case of non reacting surfaces, these additives become inactive. Recently developped lubrication strategies consist in the use of dispersion in oils of nano additives able to build the protective tribofilm in the sliding contact without reaction with the surfaces. Carbon fluorinated phases, due to their lamellar structure and their high chemical stability even at relatively high temperature (400°C) represent interesting candidates as lubricant nano-additives subjected to present friction reduction, anti wear and anti corrosion actions. This work presents the tribologic behaviour of some carbon fluorinated derivatives such as graphite fluorides, fluorinated carbon nanofibers, fluorinated carbon nanodiscs and fluorinated carbon blacks. The influence, on the tribologic performances, of the structure of the initial carbon phases, of the fluorination rate (0
World Tribology Congress 2013
Torino, Italy

Droits : info:eu-repo/semantics/OpenAccess
hal-00926514
https://hal.archives-ouvertes.fr/hal-00926514
https://hal.archives-ouvertes.fr/hal-00926514/document
https://hal.archives-ouvertes.fr/hal-00926514/file/Delbe_9783.pdf
OATAO : 9783

Éditeur(s) : HAL CCSD Oxford University Press (OUP)
Résumé : International audience
Retreatment with pegylated interferon (peg-IFN) and ribavirin (RBV) results in poor sustained virological response (SVR) rates in human immunodeficiency virus (HIV)/hepatitis C virus (HCV)-coinfected patients. There are limited data regarding the use of telaprevir plus peg-IFN/RBV in this population. HIV type 1-infected patients who previously failed ≥12 weeks of peg-IFN/RBV for HCV genotype 1 coinfection were enrolled in a single-arm, phase 2 trial. Patients with cirrhosis and previous null response were excluded. Authorized antiretrovirals were tenofovir, emtricitabine, efavirenz, atazanavir, and raltegravir. All patients received peg-IFN alfa-2a (180 µg/week) plus RBV (1000-1200 mg/day) for 4 weeks, followed by telaprevir (750 mg or 1125 mg every 8 hours with efavirenz) plus peg-IFN/RBV for 12 weeks and peg-IFN/RBV for 32-56 weeks according to virological response at week 8. The primary endpoint was the SVR rate at 24 weeks after the end of treatment (SVR24). Sixty-nine patients started treatment; SVR24 was achieved in 55 (80% [95% confidence interval, 68%-88%). SVR24 was not influenced by baseline fibrosis stage, IL28B genotype, antiretroviral regimen, HCV subtype, CD4 cell count, previous response to HCV treatment, HCV RNA level, or HCV RNA decline at week 4. HCV treatment was discontinued for adverse events (AEs) in 20% of patients, including cutaneous (4%), psychiatric (4%), hematological (6%), and other AEs (6%). Peg-IFN or RBV dose reduction was required in 23% and 43% of patients, respectively. Seventy percent of patients required erythropoietin, blood transfusions, or RBV dose reduction for anemia. Two patients died during the study. No HIV breakthrough was observed. Despite a high discontinuation rate related to toxicity, a substantial proportion of treatment-experienced HIV-coinfected patients achieved SVR24 with a telaprevir-based regimen. Clinical Trials Registration. NCT01332955.
ISSN: 1058-4838

hal-01118447
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01118447
PUBMED : 25139963
DOI : 10.1093/cid/ciu659

Éditeur(s) : HAL CCSD Wiley-Blackwell
Résumé : International audience
AIMS: Virus detection has often been difficult due to a low concentration in water. In this study, we developed a new procedure based on concentration of virus particles on an innovative support: poly-L-lysine dendrigrafts (DGL), coupled with directed nucleic acid extraction and real-time PCR quantification. METHODS AND RESULTS: This method was evaluated using the bacteriophage MS2 as a model virus. This virus exhibited the size and structural properties of human pathogenic enteric viruses and has often been used to assess new supports of concentration. Moreover, this bacteriophage is also a faecal contamination indicator. In this study, many water filtration conditions were tested (volume of water, concentration, etc.), and more than 80% of bacteriophage were recovered after filtration on polymer, in most conditions. We demonstrated that the method was linear (slope = 0*99 ± 0*04 and Y intercept when x = -0*02 ± 0*28), valid (as manipulators, tested concentrations, volumes of sample and batch of polymer did not have any influence on concentration) and sensitive (allowing to concentrate up to 16,600-fold 1 l of sample and to detect and quantify down to 750 GC l(-1) and 7500 GC l(-1), respectively). CONCLUSIONS: To conclude, this support exhibits high interest to retain viruses and to allow to detect low concentration of virus in water. SIGNIFICANCE AND IMPACT OF THE STUDY: This study gives valuable advance in the methods of concentration and diagnosis of virus in water.
Journal of Applied Microbiology

hal-00828987
https://hal.archives-ouvertes.fr/hal-00828987
DOI : 10.1111/jam.12209
PUBMED : 23551794

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
The structural parameters of fluorinated nanocarbons presenting different shapes, i.e. spherical, tubular and discotic are investigated and correlated to their tribological properties. Different fluorination rates of graphitized carbon blacks (0D), carbon nanofibres (1D) and a mixture of carbon nanodiscs and nanocones (2D) were achieved under pure molecular fluorine gas flow (direct fluorination). Raman spectrometry, X-ray diffraction and 19F solid state nuclear magnetic resonance underline similar structure and nature of the C-F bonds (covalent) for equivalent fluorine contents. In spite of the similarities of physical-chemical properties at equivalent fluorine contents, the tribological properties of the fluorinated nanocarbons differ. Those properties are discussed taking into account the role of the fluorine content and location of the fluorine atoms in the decrease of the interparticle interactions and in the cleavage of the external fluorocarbon layers to form the tribofilm. Finally, the effect of the shape is discussed.
ISSN: 0022-1139

hal-00787267
https://hal.archives-ouvertes.fr/hal-00787267

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
Despite many studies, our understanding of silica precipitation from natural waters remains limited, in particular for geothermal waters. Here we present a detailed study on the kinetics of silica polymerization as a function of fluid temperature and pH using high-temperature (250-260 °C) seawater-derived geothermal fluids as those discharged from the Bouillante geothermal site.We monitored the on-site decrease in monomeric silica concentration(initial SiO2 concentration of about 600 mg/l)with time using the molybdenum blue spectrophotometric method on samples of separated water collected from the high-pressure separator at 167 °C and cooled to 25, 50, 75, and 90 °C and for pH values ranging from 5 to 8. During all these experiments, only silica polymerization was observed, with the formation of colloidal particles in suspension in the solutions. No scaling of amorphous silica was formed. The collected data were after modeled in order to determine the useful kinetic parameters for predicting and preventing amorphous silica precipitation in the production wells during fluid exploitation in the specific context of Bouillante. Results under the investigated experimental conditions show that the kinetics of silica precipitation is affected more strongly by pH than by temperature change. The reaction in the acidic Bouillante solution begins with a transition period that significantly decreases the kinetics of silica polymerization. Modeling the experimental data indicates that the silica polymerization up to the state of equilibrium is characterized by a 2nd-order kinetic law relative to dissolved silica; this could indicate that the polymerization is controlled mainly by the formation of dimers. However, the first hour of the experiments is better characterized by a 4th-order kinetic law, suggesting more complex polymerization reactions in the initial stage with the formation of nanocolloidal particles containing 3 to 4 monomers. In both cases, the corresponding kinetics rate constant k is linearly dependent on pH for pH between 5 and 7. The activation energy Ea for the overall reaction, calculated using the Arrhenius equation under the considered pH and temperature conditions, ranges between 41±9.8 and 54±9.6 kJ/mol. To complete this work, the colloid particles formed at the end of the kinetics experiments were extracted and analyzed by SEM and TEM microscopy, X-ray Diffraction and the BET method. Results show that the size of the colloids increase and their specific surface decrease with increasing pH and are thus dependent on pH. Globally, our work provides a reliable database for understanding silica polymerization kinetics in natural geothermal brines or geologic waters characterized by a near neutral pH and moderate dissolved silica concentrations.
ISSN: 0009-2541

hal-01403092
https://hal-brgm.archives-ouvertes.fr/hal-01403092
DOI : 10.1016/j.chemgeo.2016.08.031

Éditeur(s) : HAL CCSD Wiley-Blackwell
Résumé : International audience
Virus detection has often been difficult due to a low concentration in water. In this study, we developed a new procedure based on concentration of virus particles on an innovative support: poly-L-lysine dendrigrafts (DGL), coupled with directed nucleic acid extraction and real-time PCR quantification. Methods and Results: This method was evaluated using the bacteriophage MS2 as a model virus. This virus exhibited the size and structural properties of human pathogenic enteric viruses and has often been used to assess new supports of concentration. Moreover, this bacteriophage is also a faecal contamination indicator. In this study, many water filtration conditions were tested (volume of water, concentration, etc.), and more than 80% of bacteriophage were recovered after filtration on polymer, in most conditions. We demonstrated that the method was linear (slope = 0 99 0 04 and Y intercept when x = 0 02 0 28), valid (as manipulators, tested concentrations, volumes of sample and batch of polymer did not have any influence on concentration) and sensitive (allowing to concentrate up to 16 600-fold 1 l of sample and to detect and quantify down to 750 GC l 1 and 7500 GC l 1, respectively). Conclusions: To conclude, this support exhibits high interest to retain viruses and to allow to detect low concentration of virus in water. Significance and Impact of the Study: This study gives valuable advance in the methods of concentration and diagnosis of virus in water.
Journal of Applied Microbiology

hal-00932328
https://hal.archives-ouvertes.fr/hal-00932328
DOI : 10.1111/jam.12209

Éditeur(s) : HAL CCSD
Résumé :  
absent
Salon International de l'Agriculture

hal-01032109
https://hal.archives-ouvertes.fr/hal-01032109

Éditeur(s) : HAL CCSD Centers for Disease Control and Prevention
Résumé : International audience
To determine when risk for Buruli ulcer is highest, we examined seasonal patterns in a highly disease-endemic area of Cameroon during 2002-2012. Cases peaked in March, suggesting that risk is highest during the high rainy season. During and after this season, populations should increase protective behaviors, and case detection efforts should be intensified.
ISSN: 1080-6040

Droits : http://creativecommons.org/licenses/by-nc-nd/
hal-01307147
https://hal-amu.archives-ouvertes.fr/hal-01307147
https://hal-amu.archives-ouvertes.fr/hal-01307147/document
https://hal-amu.archives-ouvertes.fr/hal-01307147/file/14-1336.pdf
DOI : 10.3201/eid2108.141336