158 research outputs found

    The extraordinary evolutionary history of the reticuloendotheliosis viruses

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    The reticuloendotheliosis viruses (REVs) comprise several closely related amphotropic retroviruses isolated from birds. These viruses exhibit several highly unusual characteristics that have not so far been adequately explained, including their extremely close relationship to mammalian retroviruses, and their presence as endogenous sequences within the genomes of certain large DNA viruses. We present evidence for an iatrogenic origin of REVs that accounts for these phenomena. Firstly, we identify endogenous retroviral fossils in mammalian genomes that share a unique recombinant structure with REVs—unequivocally demonstrating that REVs derive directly from mammalian retroviruses. Secondly, through sequencing of archived REV isolates, we confirm that contaminated Plasmodium lophurae stocks have been the source of multiple REV outbreaks in experimentally infected birds. Finally, we show that both phylogenetic and historical evidence support a scenario wherein REVs originated as mammalian retroviruses that were accidentally introduced into avian hosts in the late 1930s, during experimental studies of P. lophurae, and subsequently integrated into the fowlpox virus (FWPV) and gallid herpesvirus type 2 (GHV-2) genomes, generating recombinant DNA viruses that now circulate in wild birds and poultry. Our findings provide a novel perspective on the origin and evolution of REV, and indicate that horizontal gene transfer between virus families can expand the impact of iatrogenic transmission events

    Strong fisheries management and governance positively impact ecosystem status

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    Bundy, Alida ... et al.-- 28 pages, 6 figures, 8 tables, supporting information https://dx.doi.org/10.1111/faf.12184Fisheries have had major negative impacts on marine ecosystems, and effective fisheries management and governance are needed to achieve sustainable fisheries, biodiversity conservation goals and thus good ecosystem status. To date, the IndiSeas programme (Indicators for the Seas) has focussed on assessing the ecological impacts of fishing at the ecosystem scale using ecological indicators. Here, we explore fisheries ‘Management Effectiveness’ and ‘Governance Quality’ and relate this to ecosystem health and status. We developed a dedicated expert survey, focused at the ecosystem level, with a series of questions addressing aspects of management and governance, from an ecosystem-based perspective, using objective and evidence-based criteria. The survey was completed by ecosystem experts (managers and scientists) and results analysed using ranking and multivariate methods. Results were further examined for selected ecosystems, using expert knowledge, to explore the overall findings in greater depth. Higher scores for ‘Management Effectiveness’ and ‘Governance Quality’ were significantly and positively related to ecosystems with better ecological status. Key factors that point to success in delivering fisheries and conservation objectives were as follows: the use of reference points for management, frequent review of stock assessments, whether Illegal, Unreported and Unregulated (IUU) catches were being accounted for and addressed, and the inclusion of stakeholders. Additionally, we found that the implementation of a long-term management plan, including economic and social dimensions of fisheries in exploited ecosystems, was a key factor in successful, sustainable fisheries management. Our results support the thesis that good ecosystem-based management and governance, sustainable fisheries and healthy ecosystems go togetherThis is a contribution to the IndiSeas Working Group, which, by the time of the study, was cofunded by IOC-UNESCO (www.ioc-unesco.org), EuroMarine (http://www.euromarinenetwork.eu), the European FP7 MEECE research project, the European Network of Excellence Eur-Oceans and the FRB EMIBIOS project (contract n°212085)Peer Reviewe

    Accouchement de jumeaux conjoints de découverte fortuite au cours du travail au CHU de Dakar

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    L’objectif de cette étude était de rapporter 3 cas de jumeaux conjoints, discuter de l’importance du diagnostic anténatal et de décrire les particularités diagnostiques, thérapeutiques et évolutives. Sur 45700 accouchements du 1er Février 2009 au 31 Décembre 2011, 3 cas de jumeaux conjoints ont été enregistrés, soit 1 cas pour 15000 accouchements. Ces cas ont été diagnostiqués au cours du travail au décours d’une dystocie mécanique ou d’une césarienne réalisée pour une autre indication. Il s’agissait d’un cas de jumeaux conjoints thoraco-omphalopages, un cas de diprosopes et un cas de dicéphales. L’accouchement dans les trois cas était fait par voie haute permettant d’extraire des mort-nés frais. Nous insistons sur l’intérêt d’un diagnostic anténatal précoce par le recours à l’échographie afin d’éviter les accidents mécaniques d’un accouchement qui ne saurait s’accomplir par voie basse.Key words: Jumeaux conjoints, diprosopes, dicéphales, thoraco-omphalopage

    Connaissances, attitudes et pratiques de la population du Hodh El Gharbi (Mauritanie) face au virus de l’immunodéficience humaine(VIH).

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    Il s’agit d’une enquête transversale, descriptive et analytique menée au centre hospitalier d’Aïoun sur la période du 1er janvier au 31 mai 2013. L’objectif global de notre travail était de décrire les connaissances, attitudes et pratiques sur le VIH/SIDA des patients reçus en consultation pour une infection sexuellement transmissible (IST). De façon spécifique, notre travail visait à évaluer les comportements sexuels à risque d’infection par le VIH et l’acceptation du test de dépistage volontaire chez ces consultants. Le dépistage volontaire du VIH n’était pas gratuit. L’information était recueillie à partir d’un questionnaire auto rempli. En cinq mois, 167 patients ont consenti à participer à l’étude soit 15,84%. Le sex-ratio H/F était de 0,65 et l'âge moyen était de 30 ± 5 ans [15-45ans]. Plus de la moitié (58,1%) provenait du milieu rural. Parmi eux 89,2% étaient non instruits. Les connaissances générales sur les modes de transmission du VIH étaient erronées dans 94,6% des cas. Le préservatif n’avait jamais été utilisé par les enquêtés (91,6%). Le principal motif de consultation était les leucorrhées (45,5%) suivies des mictions douloureuses (22,2%). Le dépistage volontaire pour le VIH était effectué par 4,8% des enquêtés. Un lien statistiquement significatif a été retrouvé entre la connaissance des modes de transmission du VIH, l’âge, le sexe, la provenance, le niveau d’éducation scolaire, le manque d’information et l’absence d’utilisation du préservatif. Nos résultats ont révélé chez les consultants pour IST, des connaissances, attitudes et pratiques qui exposent à une grande vulnérabilité au VIH. A l'issue de ce travail, vu le lien étroit entre les IST et le VIH, nous recommandons le développement de stratégies globales de prévention (population générale) et ciblée (consultants IST) afin de réduire le risque d'infection par le VIH dans la région, en particulier chez les porteurs d'IST

    Response of stratospheric water vapor and ozone to the unusual timing of El Niño and the QBO disruption in 2015–2016

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    This is the final version. Available from European Geosciences Union via the DOI in this record.The stratospheric circulation determines the transport and lifetime of key trace gases in a changing climate, including water vapor and ozone, which radiatively impact surface climate. The unusually warm El Niño–Southern Oscillation (ENSO) event aligned with a disrupted Quasi-Biennial Oscillation (QBO) caused an unprecedented perturbation to this circulation in 2015–2016. Here, we quantify the impact of the alignment of these two phenomena in 2015–2016 on lower stratospheric water vapor and ozone from satellite observations. We show that the warm ENSO event substantially increased water vapor and decreased ozone in the tropical lower stratosphere. The QBO disruption significantly decreased global lower stratospheric water vapor and tropical ozone from early spring to late autumn. Thus, this QBO disruption reversed the lower stratosphere moistening triggered by the alignment of the warm ENSO event with westerly QBO in early boreal winter. Our results suggest that the interplay of ENSO events and QBO phases will be crucial for the distributions of radiatively active trace gases in a changing future climate, when increasing El Niño-like conditions and a decreasing lower stratospheric QBO amplitude are expected.European CommissionEuropean CommissionNatural Environment Research Council (NERC)Helmholtz Associatio

    Ethnomedical, hytochemical and biological investigations of Margaritaria discoidea (Baill.) Webster, a plant species widely used in Guinean traditional medicine

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    peer reviewedThe charged particle transverse momentum (pT) spectra are presented for pp collisions at sqrt(s)=0.9 and 7 TeV. The data samples were collected with the CMS detector at the LHC and correspond to integrated luminosities of 231 inverse microbarns and 2.96 inverse picobarns, respectively. Calorimeter-based high-transverse-energy triggers are employed to enhance the statistical reach of the high-pT measurements. The results are compared with both leading-order QCD and with an empirical scaling of measurements at different collision energies using the scaling variable xT = 2 pT/sqrt(s) over the pT range up to 200 GeV/c. Using a combination of xT scaling and direct interpolation at fixed pT, a reference transverse momentum spectrum at sqrt(s)=2.76 TeV is constructed, which can be used for studying high-pT particle suppression in the dense QCD medium produced in heavy-ion collisions at that centre-of-mass energy

    The evolutionary significance of polyploidy

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    Polyploidy, or the duplication of entire genomes, has been observed in prokaryotic and eukaryotic organisms, and in somatic and germ cells. The consequences of polyploidization are complex and variable, and they differ greatly between systems (clonal or non-clonal) and species, but the process has often been considered to be an evolutionary 'dead end'. Here, we review the accumulating evidence that correlates polyploidization with environmental change or stress, and that has led to an increased recognition of its short-term adaptive potential. In addition, we discuss how, once polyploidy has been established, the unique retention profile of duplicated genes following whole-genome duplication might explain key longer-term evolutionary transitions and a general increase in biological complexity

    Field-based evidence of fast and global increase of Plasmodium falciparum drug-resistance by DNA-microarrays and PCR/RFLP in Niger

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    <p>Abstract</p> <p>Background</p> <p>Over the last years, significant progress has been made in the comprehension of the molecular mechanism of malaria resistance to drugs. Together with <it>in vivo </it>tests, the molecular monitoring is now part of the survey strategy of the <it>Plasmodium </it>sensitivity. Currently, DNA-microarray analysis allows the simultaneous study of many single nucleotide polymorphisms (SNP) of <it>Plasmodium </it>isolates. In December 2005, the International Federation of the Red Cross distributed two million three hundred thousand long-lasting insecticide nets to pregnant women and mothers of under five years children in the whole Niger. Then, Niger adopted artemisinin-based combination therapy as first-line treatment.</p> <p>Methods</p> <p>Thirty four SNPs of <it>pfcrt, pfdhfr, pfdhps, pfmdr </it>and <it>pfATPase </it>were analysed by DNA-microarray and PCR/RFLP in two villages – Zindarou and Banizoumbou – with different durations of malaria transmission. The main objective of the study was to measure the dynamics <it>of Plasmodium falciparum </it>resistant strains and associated factors.</p> <p>Results</p> <p>This study shows a global and clear increase of the drug-resistance associated molecular markers frequencies during a relatively short-time period of four years. Markers associated with resistance to chloroquine and sulphonamids were more frequently found in the short transmission zone than in the long transmission one. The <it>pfcrt76T </it>mutation is significantly more present at Banizoumbou than Zindarou (38.3% vs 25.2%, p = 0.013).</p> <p>This work allowed the screening of several field strains for five SNPs of <it>PfATPase6 </it>gene. The <it>pfATPase6S769N</it>, candidate mutation of resistance to artemisinin was not found. However the <it>pfATPsaeA623E </it>mutation was found in 4.7% of samples.</p> <p>Conclusion</p> <p>A significant increase of several SNPs frequencies was highlighted over a four-year period. The polymorphism of five <it>PfATPase6 </it>gene SNPs was described. The global, large and fast increase of the molecular resistance is discussed in the context of current changes of health policy and malaria control in Niger.</p

    Discrepancies between survey and administrative data on the use of mental health services in the general population: findings from a study conducted in Québec

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    <p>Abstract</p> <p>Background</p> <p>Population surveys and health services registers are the main source of data for the management of public health. Yet, the validity of survey data on the use of mental health services has been questioned repeatedly due to the sensitive nature of mental illness and to the risk of recall bias. The main objectives of this study were to compare data on the use of mental health services from a large scale population survey and a national health services register and to identify the factors associated with the discrepancies observed between these two sources of data.</p> <p>Methods</p> <p>This study was based on the individual linkage of data from the cycle 1.2 of the Canadian Community Health Survey (CCHS-1.2) and from the health services register of the Régie de l'assurance maladie du Québec (RAMQ). The RAMQ is the governmental agency managing the Quebec national health insurance program. The analyses mostly focused on the 637 Quebecer respondents who were recorded as users of mental health services in the RAMQ and who were self-reported users or non users of these services in the CCHS-1.2.</p> <p>Results</p> <p>Roughly 75%, of those recorded as users of mental health services users in the RAMQ's register did not report using mental health services in the CCHS-1.2. The odds of disagreement between survey and administrative data were higher in seniors, individuals with a lower level of education, legal or de facto spouses and mothers of young children. They were lower in individuals with a psychiatric disorder and in frequent and more recent users of mental health services according to the RAMQ's register.</p> <p>Conclusions</p> <p>These findings support the hypotheses that social desirability and recall bias are likely to affect the self-reported use of mental health services in a population survey. They stress the need to refine the investigation of mental health services in population surveys and to combine survey and administrative data, whenever possible, to obtain an optimal estimation of the population need for mental health care.</p

    Falciparum malaria and HIV-1 in hospitalized adults in Maputo, Mozambique: does HIV-infection obscure the malaria diagnosis?

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    <p>Abstract</p> <p>Background</p> <p>The potential impact of HIV-1 on falciparum malaria has been difficult to determine because of diagnostic problems and insufficient epidemiological data.</p> <p>Methods</p> <p>In a prospective, cross-sectional study, clinical and laboratory data was registered consecutively for all adults admitted to a medical ward in the Central Hospital of Maputo, Mozambique, during two months from 28<sup>th </sup>October 2006. Risk factors for fatal outcome were analysed. The impact of HIV on the accuracy of malaria diagnosis was assessed, comparing "Presumptive malaria", a diagnosis assigned by the ward clinicians based on fever and symptoms suggestive of malaria in the absence of signs of other infections, and "Verified malaria", a malaria diagnosis that was not rejected during retrospective review of all available data.</p> <p>Results</p> <p>Among 333 included patients, fifteen percent (51/333) had "presumptive malaria", ten percent (28 of 285 tested persons) had positive malaria blood slides, while 69.1% (188/272) were HIV positive. Seven percent (n = 23) had "verified malaria", after the diagnosis was rejected in patients with neck stiffness or symptom duration longer than 2 weeks (n = 5) and persons with negative (n = 19) or unknown malaria blood slide (n = 4). Clinical stage of HIV infection (CDC), hypotension and hypoglycaemia was associated with fatal outcome. The "presumptive malaria" diagnosis was rejected more frequently in HIV positive (20/31) than in HIV negative patients (2/10, p = 0.023).</p> <p>Conclusion</p> <p>The study suggests that the fraction of febrile illness attributable to malaria is lower in HIV positive adults. HIV testing should be considered early in evaluation of patients with suspected malaria.</p
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