Evolutionary genetic aspects of host association in generalist ectoparasites

Despite the use of the host for dispersal by most parasite species, the extremely loose relationship typical between highly mobile hosts and generalist ectoparasites may lead to very different gene flow patterns between the two, leading in turn to different spatial genetic structure, and potentially different demographic history. I examined how similar gene flow patterns are between Cimex adjunctus, a generalist ectoparasite of bats present throughout North America, and two of its key bat hosts. I first analyzed the continent-scale genetic structure and demographic history of C. adjunctus and compared it to that of two of its hosts, the little brown myotis and the big brown bat, using microsatellite and mitochondrial data. Second, I compared spatial genetic structure of C. adjunctus with Cimex lectularius, or common bed bug, which associates with a broader range of host species. Third, I compared the effect of land cover on spatial genetic structure of C. adjunctus and of the big brown bat in the Great Lakes region. My results support the emerging hypothesis that generalist ectoparasites and their highly mobile hosts display weak, but positive, correlation in spatial genetic structure and demographic history. Generalist parasites associate with different hosts, which are, in some cases, evolutionarily divergent from each other. In such cases, it is not clear how hosts may affect adaptive genetic variation in the parasites. In the Cimex genus, parasite species associate with a range of hosts, including bats, humans, and swallows. I examined how hosts affect adaptive genetic variation in these generalist ectoparasites. I analyzed variation at two salivary protein genes, one coding for an apyrase and the other for a nitrophorin, in 10 species of Cimex. These proteins affect the way parasites feed on their hosts, by preventing clotting and vasoconstriction, and may experience selection depending on host ecology or physiology. I also analyzed allelic divergence at the same two genes in a single species, C. adjunctus, associated with several bat species in North America. My results suggest selection and adaptation to the host at genes coding for salivary proteins of blood-feeding ectoparasites across the Cimex genus, and also within C. adjunctus

Structure génétique et potentiel de propagation de la rage chez deux mésocarnivores vecteurs le raton laveur(Procyon lotor) et la moufette rayée(Mephitis mephitis)

Mon premier objectif spécifique était de déterminer le niveau de structure génétique et les éléments du paysage du Sud du Québec qui sont susceptibles d'affecter cette structure génétique chez les moufettes rayées. J'ai aussi évalué s'il existe des effets spécifiques au sexe en comparant la structure génétique entre les mâles et les femelles. Pour ce faire, j'ai genotypé à 9 loci microsatellites 289 individus capturés dans les régions de la Montérégie et de l'Estrie, au Québec. Mes résultats montrent que la présence des rivières à fort débit et possiblement aussi des autoroutes provoquent une augmentation de la structure génétique surtout chez les femelles de cette espèce. Ces résultats suggèrent aussi que les mâles de la moufette rayée seraient potentiellement des vecteurs plus actifs dans la propagation de la variante de la rage du raton laveur que les femelles, puisqu'ils ne semblent pas limités autant que les femelles par les éléments du paysage. Finalement, puisque les mâles ne semblent que très peu limités par les barrières potentielles du paysage, celles-ci ne peuvent pas être utilisées pour contrôler efficacement la propagation de la maladie.Mon deuxième objectif spécifique était de déterminer s'il existe une différence de diversité et/ou de structure génétique entre des ratons laveurs testés positifs et des ratons laveurs testés négatifs pour la rage. Une telle différence serait un indice d'un comportement de déplacement différent entre ces deux groupes. Ceci peut entre autres me permettre de vérifier la validité des résultats obtenus en étudiant des individus sains d'une espèce vectrice de la maladie pour tenter d'inférer le patron de propagation de la rage du raton laveur. Mes résultats montrent que la structure génétique ne diffère pas entre les ratons laveurs sains et les ratons laveurs rabiques, indiquant un comportement de déplacement probablement similaire entre les deux groupes. Donc, les éléments du paysage auraient possiblement un effet similaire sur les ratons laveurs rabiques et sains. Les études sur la structure génétique chez des ratons laveurs sains pourraient donc fort probablement nous informer sur les couloirs de propagation potentiels de la rage du raton laveur. Ensuite, j'ai tenté de déterminer si la diversité génétique pouvait influencer l'infection par la rage en comparant la diversité génétique à différents loci entre les animaux rabiques et sains. Une différence de diversité génétique entre les deux groupes pourrait indiquer un plus grand taux d'immigration provenant de populations adjacentes chez un des groupes. Par ailleurs, une grande diversité génétique pourrait être un élément pouvant potentiellement limiter la propagation de la rage du raton laveur. Or, mes résultats ne supportent pas que la diversité génétique puisse influencer la probabilité d'un individu d'être infecté par la rage.--Résumé abrégé par UMI

Les effets de la Proximité sur l’exécution des politiques publiques : l'exemple d'un Centre de Lutte contre le Cancer (CLCC)

Les principes du nouveau management public infusent progressivement le secteur hospitalier, un secteur marqué par de profondes transformations. La manière dont s'expriment les politiques publiques dans ces établissements permet de mettre en évidence des injonctions paradoxales que les acteurs œuvrant en leur sein tentent de concilier. La mobilisation de la grille de la proximité apporte une lecture originale des manières dont les politiques publiques sont exécutées pour notamment faire face à ces nouveaux défis. Les dimensions de la proximité sont utilisées ici pour étudier la confiance entre les acteurs, le contrôle organisationnel et la légitimité des politiques publiques. La recherche porte sur l'étude du cas d'un Centre de Lutte Contre le Cancer (CLCC). Cette étude croise des données secondaires (comptes rendus de réunion, présentation du plan stratégique du Centre, organigramme, rapports de gestion) et des entretiens semi-directifs auprès de personnels des quatre catégories les plus représentatives du personnel hospitalier (dirigeants, médecins, personnels de soin, personnel des fonctions support).The principles of the new public management are gradually infusing the hospital sector, a sector marked by deep transformations. The way in which public policies are expressed in these institutions makes it possible to highlight paradoxical injunctions that the actors working with try to reconcile. The mobilization of the proximity grid provides an original reading of the ways in which public policies are implemented in order to face these new challenges. The dimensions of proximity are used here to study trust between actors, organizational control and the legitimacy of public policies. The research focuses on the case study of a French Comprehensive cancer Center (FCCC). This study collates secondary data (meeting reports, presentation of the Center’s strategic plan, organization chart, and management reports) and semi-structured interviews with staff of the four most representative categories of hospital employees (managers, doctors, care, support staff)

Uncovering spatial variation in maternal healthcare service use at subnational level in Jimma zone, Ethiopia

Re-directing resources to vulnerable sub-groups and locations is necessary to ensure equitable progress in maternal health. Analysis of disaggregated national data suggest uneven access to essential maternal healthcare services. Of major concern are women who are the most vulnerable and in need of healthcare services, being least likely to access them. Mapping of core maternal healthcare service-use indicators can serve as a decision-making tool. This analysis focuses on services across the continuum of maternal healthcare: antenatal care, maternity waiting home use, delivery care at health facilities, and postnatal care, in three rural woredas in Jimma Zone, Ethiopia.Global Affairs Canada (GAC)Canadian Institutes of Health Research (CIHR

Arbovirus vectors of epidemiological concern in the Americas: A scoping review of entomological studies on Zika, dengue and chikungunya virus vectors

Background Three arthropod-borne viruses (arboviruses) causing human disease have been the focus of a large number of studies in the Americas since 2013 due to their global spread and epidemiological impacts: Zika, dengue, and chikungunya viruses. A large proportion of infections by these viruses are asymptomatic. However, all three viruses are associated with moderate to severe health consequences in a small proportion of cases. Two mosquito species, Aedes aegypti and Aedes albopictus, are among the world´s most prominent arboviral vectors, and are known vectors for all three viruses in the Americas. Objectives This review summarizes the state of the entomological literature surrounding the mosquito vectors of Zika, dengue and chikungunya viruses and factors affecting virus transmission. The rationale of the review was to identify and characterize entomological studies that have been conducted in the Americas since the introduction of chikungunya virus in 2013, encompassing a period of arbovirus co-circulation, and guide future research based on identified knowledge gaps. Methods The preliminary search for this review was conducted on PubMed (National Library of Health, Bethesda, MD, United States). The search included the terms ´zika´ OR ´dengue´ OR ´chikungunya´ AND ´vector´ OR ´Aedes aegypti´ OR ´Aedes albopictus´. The search was conducted on March 1st of 2018, and included all studies since January 1st of 2013. Results A total of 96 studies were included in the scoping review after initial screening and subsequent exclusion of out-of-scope studies, secondary data publications, and studies unavailable in English language. Key findings We observed a steady increase in number of publications, from 2013 to 2018, with half of all studies published from January 2017 to March 2018. Interestingly, information on Zika virus vector species composition was abundant, but sparse on Zika virus transmission dynamics. Few studies examined natural infection rates of Zika virus, vertical transmission, or co-infection with other viruses. This is in contrast to the wealth of research available on natural infection and co-infection for dengue and chikungunya viruses, although vertical transmission research was sparse for all three viruses.Fil: Jones, Reilly. University of Toronto; CanadáFil: Kulkarni, Manisha A.. University of Ottawa; CanadáFil: Davidson, Thomas M.V.. University of Toronto; CanadáFil: Sander, Beate. Public Health Ontario; CanadáFil: González, Camila. Universidad de Los Andes; VenezuelaFil: Wu, Jianhong. York University ; CanadáFil: Miretti, Marcos Mateo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Biología Subtropical. Instituto de Biología Subtropical - Nodo Posadas | Universidad Nacional de Misiones. Instituto de Biología Subtropical. Instituto de Biología Subtropical - Nodo Posadas; ArgentinaFil: Espinel, Mauricio. Universidad Laica Elroy Alfaro de Manabí; EcuadorFil: Cevallos Viteri, Varsovia Enid. Instituto Nacional de Salud Pública; EcuadorFil: Cevallos, Varsovia. Instituto Nacional de Salud Pública; EcuadorFil: Talbot, Benoit. University of Ottawa; Canad

Identification of Melatonin-Regulated Genes in the Ovine Pituitary Pars Tuberalis, a Target Site for Seasonal Hormone Control

The pars tuberalis (PT) of the pituitary gland expresses a high density of melatonin (MEL) receptors and is believed to regulate seasonal physiology by decoding changes in nocturnal melatonin secretion. Circadian clock genes are known to be expressed in the PT in response to the decline (Per1) and onset (Cry1) of MEL secretion, but to date little is known of other molecular changes in this key MEL target site. To identify transcriptional pathways that may be involved in the diurnal and photoperiod-transduction mechanism, we performed a whole genome transcriptome analysis using PT RNA isolated from sheep culled at three time points over the 24-h cycle under either long or short photoperiods. Our results reveal 153 transcripts where expression differs between photoperiods at the light-dark transition and 54 transcripts where expression level was more globally altered by photoperiod (all time points combined). Cry1 induction at night was associated with up-regulation of genes coding for NeuroD1 (neurogenic differentiation factor 1), Pbef / Nampt (nicotinamide phosphoribosyltransferase) , Hif1α (hypoxia-inducible factor-1α), and Kcnq5 (K channel) and down-regulation of Rorβ, a key clock gene regulator. Using in situ hybridization, we confirmed day-night differences in expression for Pbef / Nampt, NeuroD1, and Rorβ in the PT. Treatment of sheep with MEL increased PT expression for Cry1, Pbef / Nampt, NeuroD1, and Hif1α, but not Kcnq5. Our data thus reveal a cluster of Cry1-associated genes that are acutely responsive to MEL and novel transcriptional pathways involved in MEL action in the PT

Combining genotype, phenotype and environment to infer potential candidate genes: An example using the Loblolly pine (Pinus taeda)

Population genomic analyses can be an important tool in understanding local adaptation. Identification of potential adaptive loci in such analyses is usually based on the survey of a large genomic dataset in combination with environmental variables. Phenotypic data are less commonly incorporated into such studies, although combining a genome scan analysis with a phenotypic trait analysis can greatly improve the insights obtained from each analysis individually. Here, we aimed to identify loci potentially involved in adaptation to climate in 283 Loblolly pine (Pinus taeda) samples from throughout the species’ range in the southeastern United States. We analyzed associations between phenotypic, molecular and environmental variables from a published dataset of 3,082 SNP loci and published datasets containing three categories of phenotypic traits (gene expression, metabolites, and whole-plant traits). We found only six SNP loci that displayed potential signals of local adaptation. Five of the six identified SNPs are linked to gene expression traits for lignin development, and one is linked with whole-plant traits. We subsequently compared the six candidate genes with environmental variables and found a high correlation in only three of them (R2 > 0.2). Our study highlights the need for a combination of genotypes, phenotypes, and environmental variables, and for an appropriate sampling scheme and study design, to improve confidence in the identification of potential candidate genes

Genome analysis of the necrotrophic fungal pathogens Sclerotinia sclerotiorum and Botrytis cinerea

Sclerotinia sclerotiorum and Botrytis cinerea are closely related necrotrophic plant pathogenic fungi notable for their wide host ranges and environmental persistence. These attributes have made these species models for understanding the complexity of necrotrophic, broad host-range pathogenicity. Despite their similarities, the two species differ in mating behaviour and the ability to produce asexual spores. We have sequenced the genomes of one strain of S. sclerotiorum and two strains of B. cinerea. The comparative analysis of these genomes relative to one another and to other sequenced fungal genomes is provided here. Their 38–39 Mb genomes include 11,860–14,270 predicted genes, which share 83% amino acid identity on average between the two species. We have mapped the S. sclerotiorum assembly to 16 chromosomes and found large-scale co-linearity with the B. cinerea genomes. Seven percent of the S. sclerotiorum genome comprises transposable elements compared t

Effect of statin use for the primary prevention of cardiovascular disease among older adults: a cautionary tale concerning target trials emulation

Objectives: Evidence concerning the effect of statins in primary prevention of cardiovascular disease (CVD) among older adults is lacking. Using Quebec population-wide administrative data, we emulated a hypothetical randomized trial including older adults O65 years on April 1, 2013, with no CVD history and no statin use in the previous year. Study Design and Setting: We included individuals who initiated statins and classified them as exposed if they were using statin at least 3 months after initiation and nonexposed otherwise. We followed them until March 31, 2018. The primary outcome was the composite endpoint of coronary events (myocardial infarction, coronary bypass, and percutaneous coronary intervention), stroke, and all-cause mortality. The intention-to-treat (ITT) effect was estimated with adjusted Cox models and per-protocol effect with inverse probability of censoring weighting. Results: A total of 65,096 individuals were included (mean age = 71.0 6 5.5, female = 55.0%) and 93.7% were exposed. Whereas we observed a reduction in the composite outcome (ITT-hazard ratio (HR) = 0.75; 95% CI: 0.68-0.83) and mortality (ITT-HR = 0.69; 95% CI: 0.61-0.77) among exposed, coronary events increased (ITT-HR = 1.46; 95% CI: 1.09-1.94). All multibias E-values were low indicating that the results were not robust to unmeasured confounding, selection, and misclassification biases simultaneously. Conclusion: We cannot conclude on the effectiveness of statins in primary prevention of CVD among older adults. We caution that an in-depth reflection on sources of biases and careful interpretation of results are always required in observational studies. </br

Genomic analysis of the necrotrophic fungal pathogens Sclerotinia sclerotiorum and Botrytis cinerea

This is the final version of the article. Available from the publisher via the DOI in this record.Sclerotinia sclerotiorum and Botrytis cinerea are closely related necrotrophic plant pathogenic fungi notable for their wide host ranges and environmental persistence. These attributes have made these species models for understanding the complexity of necrotrophic, broad host-range pathogenicity. Despite their similarities, the two species differ in mating behaviour and the ability to produce asexual spores. We have sequenced the genomes of one strain of S. sclerotiorum and two strains of B. cinerea. The comparative analysis of these genomes relative to one another and to other sequenced fungal genomes is provided here. Their 38-39 Mb genomes include 11,860-14,270 predicted genes, which share 83% amino acid identity on average between the two species. We have mapped the S. sclerotiorum assembly to 16 chromosomes and found large-scale co-linearity with the B. cinerea genomes. Seven percent of the S. sclerotiorum genome comprises transposable elements compared to <1% of B. cinerea. The arsenal of genes associated with necrotrophic processes is similar between the species, including genes involved in plant cell wall degradation and oxalic acid production. Analysis of secondary metabolism gene clusters revealed an expansion in number and diversity of B. cinerea-specific secondary metabolites relative to S. sclerotiorum. The potential diversity in secondary metabolism might be involved in adaptation to specific ecological niches. Comparative genome analysis revealed the basis of differing sexual mating compatibility systems between S. sclerotiorum and B. cinerea. The organization of the mating-type loci differs, and their structures provide evidence for the evolution of heterothallism from homothallism. These data shed light on the evolutionary and mechanistic bases of the genetically complex traits of necrotrophic pathogenicity and sexual mating. This resource should facilitate the functional studies designed to better understand what makes these fungi such successful and persistent pathogens of agronomic crops.The Sclerotinia sclerotiorum genome project was supported by the USDA Cooperative State Research, Education and Extension Service (USDA-NRI 2004). Sclerotinia sclerotiorum ESTs were funded by a grant to JA Rollins from USDA specific cooperative agreement 58-5442-4-281. The genome sequence of Botrytis cinerea strain T4 was funded by Genoscope, CEA, France. M Viaud was funded by the “Projet INRA Jeune-Equipe”. PM Coutinho and B Henrissat were funded by the ANR to project E-Tricel (grant ANR-07-BIOE-006). The CAZy database is funded in part by GIS-IBiSA. DM Soanes and NJ Talbot were partly funded by the UK Biotechnology and Biological Sciences Research Council. KM Plummer was partially funded by the New Zealand Bio-Protection Research Centre, http://bioprotection.org.nz/. BJ Howlett and A Sexton were partially funded by the Australian Grains Research and Development Corporation, www.grdc.com.au. L Kohn was partially funded by NSERC Discovery Grant (Natural Sciences and Engineering Research Council of Canada) - Grant number 458078. M Dickman was supported by the NSF grant MCB-092391 and BARD grant US-4041-07C. O Yarden was supported by BARD grant US-4041-07C. EG Danchin obtained financial support from the European Commission (STREP FungWall grant, contract: LSHB - CT- 2004 - 511952). A Botrytis Genome Workshop (Kaiserslautern, Germany) was supported by a grant from the German Science Foundation (DFG; HA1486) to M Hahn