17 research outputs found
Co-evolutionary analysis suggests a role for TLR9 in papillomavirus restriction
Upon infection, DNA viruses can be sensed by pattern recognition receptors (PRRs) leading to the activation of type I and III interferons, aimed at blocking infection. Therefore, viruses must inhibit these signaling pathways, avoid being detected, or both. Papillomavirus virions are trafficked from early endosomes to the Golgi apparatus and wait for the onset of mitosis to complete nuclear entry. This unique subcellular trafficking strategy avoids detection by cytoplasmic PRRs, a property that may contribute to establishment of infection. However, as the capsid uncoats within acidic endosomal compartments, the viral DNA may be exposed to detection by toll-like receptor (TLR) 9. In this study we characterize two new papillomaviruses from bats and use molecular archeology to demonstrate that their genomes altered their nucleotide composition to avoid detection by TLR9, providing evidence that TLR9 acts as a PRR during papillomavirus infection. Furthermore, we demonstrate that TLR9, like other components of the innate immune system, is under evolutionary selection in bats, providing the first direct evidence for co-evolution between papillomaviruses and their hosts
The westward journey of alfalfa leaf curl virus
Alfalfa leaf curl virus (ALCV), which causes severe disease symptoms in alfalfa (Medicago
sativa L.) and is transmitted by the widespread aphid species, Aphis craccivora Koch, has been
found throughout the Mediterranean basin as well as in Iran and Argentina. Here we reconstruct
the evolutionary history of ALCV and attempt to determine whether the recent discovery and
widespread detection of ALCV is attributable either to past diagnostic biases or to the emergence
and global spread of the virus over the past few years. One hundred and twenty ALCV complete
genome sequences recovered from ten countries were analyzed and four ALCV genotypes (ALCV-A,
ALCV-B, ALCV-C, and ALCV-D) were clearly distinguished. We further confirm that ALCV isolates
are highly recombinogenic and that recombination has been a major determinant in the origins of the
various genotypes. Collectively, the sequence data support the hypothesis that, of all the analyzed
locations, ALCV likely emerged and diversified in the Middle East before spreading to the western
Mediterranean basin and Argentina
Diverse genomoviruses representing twenty-nine species identified associated with plants
Genomoviruses (family Genomoviridae) are circular single-stranded DNA viruses that have been mainly identifed through
metagenomics studies in a wide variety of samples from various environments. Here, we describe 98 genomes of genomoviruses found associated with members of 19 plant families from Australia, Brazil, France, South Africa and the USA. These
98 genomoviruses represent 29 species, 26 of which are new, in the genera Gemykolovirus (n = 37), Gemyduguivirus (n =
9), Gemygorvirus (n = 8), Gemykroznavirus (n = 6), Gemycircularvirus (n = 21) and Gemykibivirus (n = 17)
Corrosion et altération des matériaux du nucléaire
International audienceLa maĂźtrise du phĂ©nomĂšne de la corrosion est cruciale pour l'industrie nuclĂ©aire : il y va du rendement des installations, mais aussi de leur sĂ»retĂ©.Le nuclĂ©aire est confrontĂ© Ă la corrosion pour une grande variĂ©tĂ© de matĂ©riaux placĂ©s dans des environnements trĂšs divers. La corrosion mĂ©tallique est, bien sĂ»r, Ă lâĆuvre dans le milieu chaud et aqueux des rĂ©acteurs Ă eau qui constituent l'essentiel du parc mondial. Les progrĂšs rĂ©alisĂ©s dans la maĂźtrise de la corrosion des diffĂ©rents composants de ces rĂ©acteurs permettent de les faire fonctionner dans des conditions plus sĂ»res. la corrosion est aussi prĂ©sente dans les installations de l'aval du cycle Ă©lectronuclĂ©aire (corrosion en milieu acide dans les usines de retraitement, corrosion des conteneurs de dĂ©chets en situation d'entreposage ou de stockage, etc.). Les systĂšmes nuclĂ©aires du futur Ă©largiront encore la palette des matĂ©riaux Ă Ă©tudier et des situations dans lesquelles ils seront placĂ©s (corrosion par les mĂ©taux liquides ou les impuretĂ©s de l'hĂ©lium).La corrosion ressemble souvent dans sa description Ă un patchwork de cas particuliers. Les problĂšmes de corrosion rencontrĂ©s et leurs Ă©tudes sont prĂ©sentĂ©s ici dans des chapitres relatifs aux grands secteurs du domaine nuclĂ©aire et y sont classĂ©s en fonction de leur phĂ©nomĂ©nologie. Cette monographie illustre les recherches en cours en prĂ©sentant les rĂ©sultats marquants obtenus rĂ©cemment
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The effect of salivary bypass tube use on the prevention of pharyngo-cutaneous fistulas after total laryngectomy
Introduction: The aim of this retrospective study was to assess the efficacy of Salivary Bypass Tube (SBT) for preventing pharyngo-cutaneous fistula (PCF) in a recent cohort of patients who underwent primary and salvage total laryngectomy (TL). Methods: A consecutive series of 133 patients who underwent total laryngectomy between 1997 and 2019 was reviewed. The incidence of PCF was compared between patients who did not receive SBT (nSBT group; n = 55) and those preventively receiving SBT (SBT group; n = 78) in both primary and salvage TL. Risk factors for PCF were evaluated in a univariate and multivariate analyses. Results: The overall PCF rate was 30%. Preoperative characteristics were similar between the nSBT and SBT groups, except for older age (p = 0.016), lower preoperative hemoglobin (p = 0.043), and lesser neoadjuvant chemotherapy (p = 0.015) in the SBT group. The rate of PCF the nSBT group, was 41.5%, compared to 21.8% in the SBT group (p = 0.020). In multivariate analysis, only the use of SBT was associated with lower risk of PCF (OR = 0.41 (95% CI 0.19â0.89), p = 0.026). This effect was verified only in the subgroup of patient operated for salvage TL (OR = 0.225; 95% CI 0.09â0.7; p = 0.008). Conclusion: The use of SBT in our series in salvage TL, appears to be associated with a decreased risk of PCF.SCOPUS: ar.jinfo:eu-repo/semantics/publishe
Co-evolutionary analysis suggests a role for TLR9 in papillomavirus restriction
Upon infection, DNA viruses can be sensed by pattern recognition receptors (PRRs) leading to the activation of type I and III interferons, aimed at blocking infection. Therefore, viruses must inhibit these signaling pathways, avoid being detected, or both. Papillomavirus virions are trafficked from early endosomes to the Golgi apparatus and wait for the onset of mitosis to complete nuclear entry. This unique subcellular trafficking strategy avoids detection by cytoplasmic PRRs, a property that may contribute to establishment of infection. However, as the capsid uncoats within acidic endosomal compartments, the viral DNA may be exposed to detection by toll-like receptor (TLR) 9. In this study we characterize two new papillomaviruses from bats and use molecular archeology to demonstrate that their genomes altered their nucleotide composition to avoid detection by TLR9, providing evidence that TLR9 acts as a PRR during papillomavirus infection. Furthermore, we demonstrate that TLR9, like other components of the innate immune system, is under evolutionary selection in bats, providing the first direct evidence for co-evolution between papillomaviruses and their hosts
Estimation de la situation du SRAS-CoV-2 en France
Traduction non relue par les auteurs de "Estimating the burden of SARS-CoV-2 in France" paru dans Science https://science.sciencemag.org/content/369/6500/208 Date de parution : 10 juillet 2020 DOI: 10.1126/science.abc3517[ATTENTION : LA TRADUCTION DE L'ARTICLE N'A PAS ĂTĂ RELUE PAR LES AUTEURS]. La France a Ă©tĂ© fortement affectĂ©e par la pandĂ©mie du syndrome respiratoire aigu sĂ©vĂšre coronavirus 2 (SRAS-CoV-2) et est entrĂ©e en confinement le 17 mars 2020. Ă l'aide de modĂšles appliquĂ©s aux donnĂ©es hospitaliĂšres et de dĂ©cĂšs, nous estimons l'impact du confinement et l'immunitĂ© actuelle de la population . Nous constatons que 2,9% des personnes infectĂ©es sont hospitalisĂ©es et 0,5% des personnes infectĂ©es dĂ©cĂšdent (intervalle de confiance Ă 95%: 0,3 Ă 0,9%), allant de 0,001% chez les moins de 20 ans Ă 8,3% chez les 80 ans ou plus ĂągĂ©s. Ă tous les Ăąges, les hommes sont plus susceptibles d'ĂȘtre hospitalisĂ©s, d'entrer en soins intensifs et de mourir que les femmes. Le confinement a rĂ©duit la reproductivitĂ© de 2,90 Ă 0,67 (rĂ©duction de 77%). D'ici le 11 mai 2020, date Ă laquelle les interventions devraient ĂȘtre assouplies, nous prĂ©voyons que 3,5 millions de personnes (fourchette: 2,1 millions Ă 6,0 millions), soit 5,3% de la population (fourchette: 3,3 Ă 9,3%), auront Ă©tĂ© infectĂ©es. L'immunitĂ© de la population semble insuffisante pour Ă©viter une deuxiĂšme vague si toutes les mesures de contrĂŽle sont relĂąchĂ©es Ă la fin du confinement
Réduire la néophobie des dindes au moment des transitions alimentaires en prenant en compte les caractéristiques visuelles et tactiles des aliments
Texte intégral sur CD ROM p:660-664Réduire la néophobie des dindes au moment des transitions alimentaires en prenant en compte les caractéristiques visuelles et tactiles des aliments. 10. Journées de la Recherche Avicole et PalmipÚdes à Foie Gra