433 research outputs found

    Phylogeography of Rift Valley Fever Virus in Africa Reveals Multiple Introductions in Senegal and Mauritania

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    Rift Valley Fever (RVF) virus (Family Bunyaviridae) is an arthropod-borne RNA virus that infects primarily domestic ruminants and occasionally humans. RVF epizootics are characterized by numerous abortions and mortality among young animals. In humans, the illness is usually characterized by a mild self-limited febrile illness, which could progress to more serious complications. RVF virus is widespread and endemic in many regions of Africa. In Western Africa, several outbreaks have been reported since 1987 when the first major one occurred at the frontier of Senegal and Mauritania. Aiming to evaluate the spreading and molecular epidemiology in these countries, RVFV isolates from 1944 to 2008 obtained from 18 localities in Senegal and Mauritania and 15 other countries were investigated. Our results suggest that a more intense viral activity possibly took place during the last century compared to the recent past and that at least 5 introductions of RVFV took place in Senegal and Mauritania from distant African regions. Moreover, Barkedji in Senegal was possibly a hub associated with the three distinct entries of RVFV in West Africa

    Molecular evolution of zika virus during its emergence in the 20th century

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    Zika virus (ZIKV) is a mosquito-borne flavivirus first isolated in Uganda in 1947. Although entomological and virologic surveillance have reported ZIKV enzootic activity in diverse countries of Africa and Asia, few human cases were reported until 2007, when a Zika fever epidemic took place in Micronesia. In the context of West Africa, the WHO Collaborating Centre for Arboviruses and Hemorrhagic Fever at Institut Pasteur of Dakar (http://www.pasteur.fr/recherche/banques/CRORA/) reports the periodic circulation of ZIKV since 1968. Despite several reports on ZIKV, the genetic relationships among viral strains from West Africa remain poorly understood. To evaluate the viral spread and its molecular epidemiology, we investigated 37 ZIKV isolates collected from 1968 to 2002 in six localities in Senegal and Côte d'Ivoire. In addition, we included strains from six other countries. Our results suggested that these two countries in West Africa experienced at least two independent introductions of ZIKV during the 20th century, and that apparently these viral lineages were not restricted by mosquito vector species. Moreover, we present evidence that ZIKV has possibly undergone recombination in nature and that a loss of the N154 glycosylation site in the envelope protein was a possible adaptive response to the Aedes dalzieli vector.Institute Pasteur of Dakar in SenegalFAPESP (Fundação de Amparo a Pesquisa do Estado de Sao Paulo, Brazil) projects #00/04205-6FAPESP (Fundação de Amparo a Pesquisa do Estado de Sao Paulo, Brazil) projects #08/17013-6FAPESP (Fundação de Amparo a Pesquisa do Estado de Sao Paulo, Brazil) projects#10/19341-4CAPES studentship, AI (project #12/04818-5)FAPESP scholarships and PMAZCNPq-PQNIH, R01-AI06914

    La adquisición de islas de patogenicidad favorece la emergencia y potencial de virulencia de Escherichia coli productor de Shiga toxina (STEC) LEE-negativo

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    STEC causa diarrea, disentería y síndrome hemolítico urémico (SHU). La Shiga toxina es el principal factor de virulenciade STEC, pero la capacidad de la bacteria para adherirse y colonizar el intestino humano es fundamental para causarenfermedad. La Isla de Patogenicidad (PAI) Locus of Enterocyte Effacement (LEE) contiene genes que median elfenotipo de adhesión de un grupo de cepas STEC (LEE-positivo) que son clínicamente relevantes debido a su asociacióncon SHU. No obstante, cepas STEC que carecen de LEE (LEE-negativo) también han sido aisladas de casos de SHU,indicando que factores de virulencia adicionales están involucrados en la patogenicidad de estas bacterias. De hecho,tres PAIs, denominadas como ?Locus of Proteolysis Activity?, ?Subtilase-Encoding Pathogenicity Island? y el ?Locus ofAdhesion and Autoaggregation? (LAA), han sido reportadas como exclusivamente presentes en STEC LEE-negativo. Sinembargo, se desconocen los mecanismos de patogénesis mediados por estas PAIs. Recientemente, la incidencia degastroenteritis causada por cepas STEC LEE-negativo ha aumentado en varios países. Por lo tanto, en este estudioinvestigamos la base genética para su emergencia y realizamos un análisis de genómica comparativa utilizando 367genomas de cepas STEC LEE-negativo aisladas a nivel mundial. Como resultado, identificamos tres nuevos elementosgenéticos, incluyendo dos PAIs y un Elemento Integrativo y Conjugativo. Además, encontramos que LAA fue la PAI másfrecuente, sugiriendo que juega un papel importante en la biología de STEC. En consecuencia, LAA fue eliminada delcromosoma de la cepa STEC E045 mediante reemplazo alélico. Posteriormente, se realizaron ensayos in vitro e in vivopara determinar si la deleción de LAA afecta la capacidad de adhesión, colonización y virulencia de la cepa E045. Sepresenta evidencia en apoyo a la participación de LAA en la colonización intestinal de un modelo murino de infecciónpor STEC. Finalmente, análisis filogenéticos indicaron que clados en los que se agrupan cepas con dos o más PAIs estángeográficamente más diseminados en comparación con clados filogenéticamente cercanos en los que se agrupan cepasque carecen o contienen una sola PAI. Este estudio es un paso adelante en el conocimiento de la evolución y virulenciade STEC.Fil: Montero, David A.. Universidad de Chile. Facultad de Medicina; ChileFil: Del Canto, Felipe. Universidad de Chile. Facultad de Medicina; ChileFil: Salazar, Juan C.. Universidad de Chile. Facultad de Medicina; ChileFil: Velasco, Juliana. Universidad de Chile. Facultad de Medicina; ChileFil: Colello, Rocío. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tandil. Centro de Investigación Veterinaria de Tandil. Universidad Nacional del Centro de la Provincia de Buenos Aires. Centro de Investigación Veterinaria de Tandil. Provincia de Buenos Aires. Gobernación. Comision de Investigaciones Científicas. Centro de Investigación Veterinaria de Tandil; ArgentinaFil: Padola, Nora Lía. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tandil. Centro de Investigación Veterinaria de Tandil. Universidad Nacional del Centro de la Provincia de Buenos Aires. Centro de Investigación Veterinaria de Tandil. Provincia de Buenos Aires. Gobernación. Comision de Investigaciones Científicas. Centro de Investigación Veterinaria de Tandil; ArgentinaFil: Oñate, Angel. Universidad de Chile. Facultad de Medicina; ChileFil: Puente, José L.. Universidad Nacional Autónoma de México. Instituto de Biotecnología; MéxicoFil: Vidal, Roberto. Universidad de Chile. Facultad de Medicina; ChileXXIV Congreso Latinoamericano de Microbiología; XL Congreso Chileno de Microbiología; II Reunión Anual de la Asociación Chilena de Inmunología y IX Reunión de la Sociedad Latinoamericana de Tuberculosis y otras MicobacteriosisSantiago de ChileChileAsociación Latinoamericana de Microbiologí

    Comparative genomics reveals high biological diversity and specific adaptations in the industrially and medically important fungal genus Aspergillus

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    Clonal chromosomal mosaicism and loss of chromosome Y in elderly men increase vulnerability for SARS-CoV-2

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    The pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2, COVID-19) had an estimated overall case fatality ratio of 1.38% (pre-vaccination), being 53% higher in males and increasing exponentially with age. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, we found 133 cases (1.42%) with detectable clonal mosaicism for chromosome alterations (mCA) and 226 males (5.08%) with acquired loss of chromosome Y (LOY). Individuals with clonal mosaic events (mCA and/or LOY) showed a 54% increase in the risk of COVID-19 lethality. LOY is associated with transcriptomic biomarkers of immune dysfunction, pro-coagulation activity and cardiovascular risk. Interferon-induced genes involved in the initial immune response to SARS-CoV-2 are also down-regulated in LOY. Thus, mCA and LOY underlie at least part of the sex-biased severity and mortality of COVID-19 in aging patients. Given its potential therapeutic and prognostic relevance, evaluation of clonal mosaicism should be implemented as biomarker of COVID-19 severity in elderly people. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, individuals with clonal mosaic events (clonal mosaicism for chromosome alterations and/or loss of chromosome Y) showed an increased risk of COVID-19 lethality

    Differential cross section measurements for the production of a W boson in association with jets in proton–proton collisions at √s = 7 TeV

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    Measurements are reported of differential cross sections for the production of a W boson, which decays into a muon and a neutrino, in association with jets, as a function of several variables, including the transverse momenta (pT) and pseudorapidities of the four leading jets, the scalar sum of jet transverse momenta (HT), and the difference in azimuthal angle between the directions of each jet and the muon. The data sample of pp collisions at a centre-of-mass energy of 7 TeV was collected with the CMS detector at the LHC and corresponds to an integrated luminosity of 5.0 fb[superscript −1]. The measured cross sections are compared to predictions from Monte Carlo generators, MadGraph + pythia and sherpa, and to next-to-leading-order calculations from BlackHat + sherpa. The differential cross sections are found to be in agreement with the predictions, apart from the pT distributions of the leading jets at high pT values, the distributions of the HT at high-HT and low jet multiplicity, and the distribution of the difference in azimuthal angle between the leading jet and the muon at low values.United States. Dept. of EnergyNational Science Foundation (U.S.)Alfred P. Sloan Foundatio

    Penilaian Kinerja Keuangan Koperasi di Kabupaten Pelalawan

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    This paper describe development and financial performance of cooperative in District Pelalawan among 2007 - 2008. Studies on primary and secondary cooperative in 12 sub-districts. Method in this stady use performance measuring of productivity, efficiency, growth, liquidity, and solvability of cooperative. Productivity of cooperative in Pelalawan was highly but efficiency still low. Profit and income were highly, even liquidity of cooperative very high, and solvability was good

    Juxtaposing BTE and ATE – on the role of the European insurance industry in funding civil litigation

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    One of the ways in which legal services are financed, and indeed shaped, is through private insurance arrangement. Two contrasting types of legal expenses insurance contracts (LEI) seem to dominate in Europe: before the event (BTE) and after the event (ATE) legal expenses insurance. Notwithstanding institutional differences between different legal systems, BTE and ATE insurance arrangements may be instrumental if government policy is geared towards strengthening a market-oriented system of financing access to justice for individuals and business. At the same time, emphasizing the role of a private industry as a keeper of the gates to justice raises issues of accountability and transparency, not readily reconcilable with demands of competition. Moreover, multiple actors (clients, lawyers, courts, insurers) are involved, causing behavioural dynamics which are not easily predicted or influenced. Against this background, this paper looks into BTE and ATE arrangements by analysing the particularities of BTE and ATE arrangements currently available in some European jurisdictions and by painting a picture of their respective markets and legal contexts. This allows for some reflection on the performance of BTE and ATE providers as both financiers and keepers. Two issues emerge from the analysis that are worthy of some further reflection. Firstly, there is the problematic long-term sustainability of some ATE products. Secondly, the challenges faced by policymakers that would like to nudge consumers into voluntarily taking out BTE LEI

    Search for stop and higgsino production using diphoton Higgs boson decays

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    Results are presented of a search for a "natural" supersymmetry scenario with gauge mediated symmetry breaking. It is assumed that only the supersymmetric partners of the top-quark (stop) and the Higgs boson (higgsino) are accessible. Events are examined in which there are two photons forming a Higgs boson candidate, and at least two b-quark jets. In 19.7 inverse femtobarns of proton-proton collision data at sqrt(s) = 8 TeV, recorded in the CMS experiment, no evidence of a signal is found and lower limits at the 95% confidence level are set, excluding the stop mass below 360 to 410 GeV, depending on the higgsino mass
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