Literatura científica selecionada sobre o tema "Vecteur viraux"
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Artigos de revistas sobre o assunto "Vecteur viraux"
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Tangy, Frédéric, e Jean-Nicolas Tournier. "Les virus au service de la santé : la vaccination". médecine/sciences 38, n.º 12 (dezembro de 2022): 1052–60. http://dx.doi.org/10.1051/medsci/2022168.
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Depuis plus de deux siècles, les virus sont utilisés, avec un succès impressionnant, comme outils de prévention des infections virales. Depuis la variole et la rage, l’histoire de la vaccinologie a suivi les pas de l’histoire de la virologie. Après les découvertes empiriques des premiers vaccins, le développement du génie génétique, de la virologie moléculaire, de la génétique inverse, la manipulation des génomes viraux, leur séquençage à haut débit et leur synthèse chimique, la maîtrise de la culture cellulaire et des méthodes de purification, ont considérablement contribué au développement de nouveaux vaccins viraux. Des vaccins à ARN messager ou à vecteur viral ont ainsi vu le jour ces dernières années et, face à la pandémie de Covid-19, ont été développés et distribués à la population en un temps record. Les virus au service de la santé ont un bel avenir devant eux, que cela soit pour prévenir d’autres pandémies, pour traiter le cancer, ou contrôler, enfin, le VIH ou le Plasmodium, l’agent du paludisme.
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Bertagnoli, Stéphane. "Actualité sur les vecteurs vaccinaux viraux". Bulletin de l'Académie Vétérinaire de France, n.º 1 (2017): 22. http://dx.doi.org/10.4267/2042/62249.
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Chouchan, Dominique. "Thérapie Génique: Loin des vecteurs viraux". Biofutur 1997, n.º 166 (abril de 1997): 11. http://dx.doi.org/10.1016/s0294-3506(97)86766-x.
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BERTAGNOLI, S., B. PIGNOLET, S. BIACCHESI, M. ELOIT, B. KLONJKOWSKI, J. RICHARDSON e M. BREMONT. "Les vecteurs viraux : outils modernes de vaccination". INRAE Productions Animales 21, n.º 1 (22 de março de 2008): 127–36. http://dx.doi.org/10.20870/productions-animales.2008.21.1.3383.
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Les vaccins destinés aux animaux appartiennent à deux grandes catégories : les vaccins à agents vivants, et ceux à agents inertes. Depuis quelques années, dans chacune de ces catégories, les innovations technologiques ont considérablement amélioré et diversifié les stratégies vaccinales disponibles en fonction des contraintes liées à des préoccupations tant d’innocuité, que d’efficacité ou encore de nature économique. C’est dans ce cadre que l’INRA a depuis de nombreuses années orienté les efforts de recherche vers l’élaboration de nouveaux vaccins s’appuyant sur la mise au point de vecteurs viraux adaptés à diverses espèces animales et susceptibles de répondre aux exigences des filières animales. Dans cette revue, nous décrivons ainsi les principes d’obtention et le développement de vecteurs vaccinaux fondés sur l’emploi de poxvirus animaux à spectre d’hôte étroit (virus myxomateux), d’adenovirus humains ou animaux défectifs (c’est-à-dire ayant perdu toute capacité à se multiplier chez l’hôte) ainsi que de rhabdovirus de poissons modifiés par génétique inverse. Des exemples d’application de vaccination non seulement contre des maladies animales d’intérêt économique, mais aussi dans le cadre de modèles de pathologie comparée permettent d’illustrer le potentiel indiscutable de ces vecteurs viraux et d’envisager leur emploi pour le contrôle de maladies animales émergentes ou réémergentes en Europe.
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Legendre, JY, J. Haensler e JS Rémy. "Les vecteurs non-viraux de thérapie génique." médecine/sciences 12, n.º 12 (1996): 1334. http://dx.doi.org/10.4267/10608/675.
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Quéméneur, Éric. "Les vecteurs viraux en immunothérapie du cancer". Annales des Mines - Réalités industrielles Novembre 2023, n.º 4 (9 de novembro de 2023): 87–91. http://dx.doi.org/10.3917/rindu1.234.0087.
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Par leurs propriétés uniques, les vecteurs viraux sont incontournables en thérapie génique ou pour l’ingénierie des thérapies cellulaires. Leur usage direct en tant qu’agent d’immunothérapie antitumorale, soit sous la forme de virus oncolytique ou comme vaccin thérapeutique, fait encore l’objet d’importants travaux de recherche et développement. L’approbation de T-Vec en 2015 a dopé le domaine des oncolytiques et près d’une vingtaine de produits sont en cours d’évaluation clinique. Les vecteurs non réplicatifs bénéficient de l’engouement général pour la vaccination thérapeutique et de l’arrivée des nouvelles classes d’antigènes. Ces deux classes d’immunothérapies virales trouvent parfaitement leur place dans les stratégies de combinaison avec d’autres modalités de traitement. Le secteur reste dynamique sur le plan de l’innovation technologique et clinique. Cet article évoque également les défis qui restent à relever pour que les vecteurs viraux puissent devenir une classe thérapeutique reconnue et industriellement mature.
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Peschanski, M. "Tyrosine hydroxylase : trois vecteurs viraux pour un gène". médecine/sciences 11, n.º 3 (1995): 474. http://dx.doi.org/10.4267/10608/2231.
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Manus, Jean-Marie. "Anémie de Fanconi : vecteurs viraux pour essai de thérapie génique". Revue Francophone des Laboratoires 2020, n.º 518 (janeiro de 2020): 10. http://dx.doi.org/10.1016/s1773-035x(20)30011-3.
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Fontenille, D., e C. Paupy. "Vecteurs et environnement pour support de l’émergence virale". Médecine et Maladies Infectieuses 38 (junho de 2008): S27—S29. http://dx.doi.org/10.1016/s0399-077x(08)72980-9.
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Martinent, E., e M. Zawati. "Le virage numérique comme vecteur d’égalité (territoriale) en santé (I)". Ethics, Medicine and Public Health 15 (outubro de 2020): 100593. http://dx.doi.org/10.1016/j.jemep.2020.100593.
Texto completo da fonteTeses / dissertações sobre o assunto "Vecteur viraux"
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Link, Peggy. "Identification des déterminants viraux responsables de la spécificité de transmission du Grapevine fanleaf virus par son nématode vecteur Xiphinema index". Université Louis Pasteur (Strasbourg) (1971-2008), 2005. http://www.theses.fr/2005STR13140.
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Le Grapevine fanleaf virus (GFLV) est responsable de la maladie du court-noué de la vigne qui affecte près de 30 % du vignoble français et n’épargne pas les autres pays viticoles. Ce virus est spécifiquement transmis par le nématode Xiphinema index et son génome est constitué de deux ARN simple brin de polarité positive. Mon travail de thèse a porté sur l’identification des déterminants viraux responsables de la spécificité de transmission du GFLV par Xiphinema index. Des travaux préalables ont montré que ces résidus étaient situés sur l’ARN2, plus précisément au niveau des 9 aminoacides C-terminaux de la protéine de mouvement et des 504 aminoacides de la protéine de capside. Une approche de génétique inverse a consisté à construire des ADNc chimériques de l’ARN2, au niveau desquels, des aminoacides cibles d’origine GFLV ont été remplacés par leurs correspondants chez l’Arabis mosaic virus (ArMV), un autre virus responsable de la maladie du court-noué qui est spécifiquement transmis par Xiphinema diversicaudatum et non par Xiphinema index. Les ARN2 chimériques obtenus ont été associés à l’ARN1 du GFLV pour tester leur infectivité sur plantes hôtes herbacées à infection systémique ainsi que leur transmissibilité par Xiphinema index. Ces travaux ont permis de montrer que seule la protéine de capside porte les déterminants de la spécificité de vection. Un modèle tridimensionnel de la capside du GFLV a été élaboré à partir de la structure cristallographique du Tobacco ringspot virus pour identifier les aminoacides situés en surface, conservés par le GFLV et spécifiques de ce virus, et ainsi éclairer le choix des mutations d’échanges de résidus. Parmi les mutants développés, deux ont déclenché une infection systémique sur plante. Leur transmissibilité par Xiphinema index est en cours d’étude. La transmissibilité des autres mutants affectant la protéine de capside n’a pas pu être testée, étant donné qu’ils ne sont pas infectieux in planta, vraisemblablement suite à un défaut d’encapsidation des ARN suggéré par des expériences de protection d’ARN après électroporation de protoplastes de Chenopodium quinoaGrapevine fanleaf virus (GFLV) causes fanleaf degeneration, one of the most severe viral diseases of grapevines worlwide. This virus is specifically transmitted by the nematode Xiphinema index and its genome consists of two single-stranded positive-sense RNA species. My thesis work focused on the identification of the molecular determinants involved in the specific transmission of GFLV by Xiphinema index. Previous studies indicated that residues responsible for transmission map to RNA2, in particular within the 9 C-terminal amino acids of the movement protein and the 504 amino acids of the coat protein. Chimeric cDNA of RNA2 were constructed by exchanging GFLV residues by their counterparts in Arabis mosaic virus (ArMV), another virus responsible for fanleaf degeneration that is specifically transmitted by Xiphinema diversicaudatum but not by Xiphinema index. The infectivity of chimeric RNA2 was tested on systemic herbaceous host plants in the presence of GFLV RNA1, as well as their transmissibility by Xiphinema index. Results indicated that the coat protein is the sole viral determinant for the specific transmission. A 3D model of the GFLV capsid was constructed from the crystal structure of Tobacco ringspot virus to identify surface amino acids that are specific and conserved among GFLV isolates for mutagenesis experiments. Two of the coat protein mutants systemically infected host plants. Their transmissibility by Xiphinema index is being tested. The transmissibility of the other mutants was not determined because they did not infect systemically host plants likely because their RNA are not encapsidated, as shown by RNA protection assays upon electroporation of Chenopodium quinoa protoplasts
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BRUYERE, ARNAUD. "Etude des determinants viraux impliques dans la transmission du beet western yellows virus (bwyv) par son vecteur, le puceron myzus persicae". Strasbourg 1, 1997. http://www.theses.fr/1997STR13128.
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Le beet western yellows virus ou bwyv est un luteovirus, qui infecte de tres nombreuses dicotyledones d'interet agronomique et provoque des jaunisses caracteristiques. Ce virus, limite aux tissus phloemiens de la plante hote, est transmis par un puceron, myzus persicae, selon le mode persistant et circulant. La capside de ce virus est constituee de deux proteines : une proteine majeure ou proteine de coque (cp) de 22,5 kda, codee par l'orf 3 et une proteine mineure ou proteine de readthrough (rt) de 74 kda. Cette proteine de rt est exprimee a partir des orf 3 et 5 grace a un mecanisme de translecture du codon de terminaison de l'orf 3, sous forme d'une proteine de fusion entre la proteine de cp et le domaine de rt. Avant mon arrivee au laboratoire, il avait ete montre que cette proteine etait necessaire a la transmission de ce virus par son vecteur. Mon travail de these a consiste a determiner les motifs presents dans cette proteine, impliques dans la transmission. Dans ce but, nous avons cree des mutants du bwyv touches dans la proteine de rt et etudie leur transmissibilite, par differentes methodes. Les resultats obtenus permettent de diviser le domaine de rt en deux sous domaines : (1) la region n-terminale du domaine de rt, tres conservee parmi les luteovirus, qui est strictement necessaire a l'expression et a l'incorporation de la proteine de rt et donc a la transmission du bwyv et intervient egalement dans l'accumulation du virus dans la plante ; (2) la region c-terminale du domaine de rt, peu conservee, qui n'est pas requise a la transmission, mais contient des determinants pour l'apparition des symptomes. Enfin, nous avons montre qu'il existe une relation entre la transmissibilite du bwyv et l'interaction in vitro entre le bwyv et la symbionine (chaperonine de type hsp-60), proteine d'origine endosymbiotique, extraite du puceron vecteur : seuls le bwyv et les mutants transmissibles se lient a la symbionine.
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Cottard, Virginie. "Développement et utilisation de vecteurs viraux et cellulaires en thérapie génique anti-inflammatoire : application à un modèle de polyarthrite rhumatoïde". Paris 7, 2003. http://www.theses.fr/2003PA077029.
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Avenel, Allan. "Caractérisation et immunomodulation de la réponse cellulaire contre les produits de thérapie génique". Electronic Thesis or Diss., Nantes Université, 2024. http://www.theses.fr/2024NANU1028.
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Les virus adéno-associés recombinants (rAAV) plus prévalent avec 45% de positivité, suivi de l'AAV8 sont des outils efficaces pour le transfert de gènes in vivo, (24%). De plus, l'évaluation du profil d’expression avec 8 médicaments approuvés par la FDA ou l'EMA aux cytokinique _ a permis de montrer des différences de États-Unis et en Europe. Cependant, il reste des fonctionnalité des lymphocytes anti-AAV8 et anti-AAV9. obstacles majeurs à surmonter pour que leur application Afin de mettre en évidence ces différences, jai développé lini é un protocole permettant d’enrichir la très rare population chez les patients. En effet, des effets indésirables liés à de lymphocytes anti-AAV8 et anti-AAV9 via leur sécrétion l'activation du système immunitaireà la suite de l'injection d'IFN-y chez des donneurs sains (n=6 et n=9 systémique de fortes doses de rAAV chez des patienen respectivement). Ces cellules ont ensuite été analysées clinique ont été rapportés, pouvant entrainer la par cytométrie spectrale grâce à un panel de 26 couleurs snspetuondeces&sals Cflemumnnleeslmpmnelmt de caractériser ces cellules selon leur partie due à une réactivation de la réponse cellulaire phénotype et leur état de différenciation. Celaa permis impliquant les lymphocytes T mémoires, développés lors d'identifier une importante sous-population de LTCD8 EM dune infection par 'AAV sauvage au cours de I'enfance. en réponse à l'AAV8 et à l'AAV9. De plus, une sous- Cette réponse reste peu caractérisée malgré son fort population de LTCD8 EMRA dans un état de impact potentiel sur l’efficacité du traitement et la santé du différenciation avancé a pu être identifié en réponse à patient. Ce travail de thèse vise donc à améliorer I'état de l'AAV8. Le développementde ces outils et les éléments connaissance de cette réponse cellulaire pré-existante de réponse qu'ils ont permis d'apporter devrait permettre, contre l'AAV. Pour cela, nous avons d'abord étudié la à — terme, — d'élaborer de nouvelles stratégies prévalence de la réponse cellulaire contre 6 s d'immunomodulation permettant de diminuer d’AAV utilisés en clinique dans une cohorte de 45-145 l'immunogénicitéde ces vecteurs AAV chez l'Homme. donneurs sains de la région Pays de la Loire. Cela a permis de mettre en évidence que, dans notre cohorte, l'AAV9 était leRecombinant adeno-associated viruses Of positive donors, followed by AAV8 with 24%. In addition,(rAAVS) are efficient tools for in vivo gene transfer,with 8 drugs approved by the FDA or the EMA in theUnited States and Europe. However, there are stillmajor hurdles to overcome to improve their efficiencyand safety in clinics. Actually, severe adverse eventsrelated to the activation of the host's immune systemfollowing systemic injection of high doses of rAAV.into patients have been reported, leading in somecases to clinical trials hold. This immunotoxicity ispartly due to a reactivation of a T cell-mediatedcellular response, developed after primary wild-typeAAV infection during childhood. This response is stillpoorly characterized, despite its strong potentialeffect on treatment efficacy and patient health. Theaim of this thesis is therefore to improve ourknowledge on this pre-existing cellular response toAAV. We first studied the prevalence of the cellularresponse towards 6 AAV serotypes used in clinicaltrials in a cohort of-45-145 healthy donors from thePays de la Loire area. Our results show that in ourcohort, AAV9 was the most prevalent with 45%assessment of the cytokine expression profile highlighteddifferences between anti-AAV8 and anti-AAV9 T cells. To furthercharacterize these cells, | developed a protocol to enrich thevery rare population of anti-AAV8 and anti-AAV9 T lymphocytesdepending on their IFN-y secretion in healthy donors (n=6 andn=9 respectively). These cells were then analyzed by spectralcytometry using a panel of 26 colors to characterize themaccording to their phenotype and state of differentiation. Thisallowed us to identify a subpopulation of EM CD8 T-cells inresponse to AAV8 and AAV9. Moreover, a subpopulation ofEMRA CD8 T-cells in an advanced state of differentiation wasidentified in response to AAV8. The development of these toolswill allow to develop innovative immunomodulatory strategies to prevent AAV immunogenicity in patient
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BELIN, CHRISTOPHE. "Recherche des determinants viraux impliques dans la transmission du virus du court-noue de la vigne (gflv) par son vecteur, le nematode xiphinema index". Université Louis Pasteur (Strasbourg) (1971-2008), 1999. http://www.theses.fr/1999STR13078.
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Le grapevine fanleaf nepovirus (gflv) et l'arabis mosaic nepovirus (armv) sont les agents de la maladie du court-noue de la vigne. Malgre une tres forte identite de sequence, gflv et armv sont transmis specifiquement par les nematodes xiphinema index et x. Diversicaudatum. Le genome de ces virus est reparti sur deux arn qui codent pour deux polyproteines. L'arn-1 assure la replication des arn et code pour la proteinase 1d#p#r#o qui mature les polyproteines. L'arn-2 est responsable de la specificite de vecteur ; il code pour la proteine 2a necessaire a sa replication et pour les proteines de mouvement (2b#m#p) et de coque (2c#c#p) permettant l'infection systemique des plantes. Pour localiser les determinants viraux responsables de la specificite gflv/x. Index, des arn-2 recombinants ont ete construits en remplacant des sequences codant pour des proteines entieres de l'arn-2 du gflv ou des domaines de la proteine 2c#c#p du gflv par les sequences correspondantes de l'armv. L'etude de ces recombinants indique l'existence d'interactions virus-specifiques des 9 residus c-terminaux de la proteine 2b#m#p avec la proteine 1d#p#r#o et avec la proteine 2c#c#p. La trans-encapsidation des arn gflv dans la capside armv a ete observee. Des proteines 2c#c#p hybrides gflv/armv ne sont pas capables de s'assembler. Un test de transmission specifique par x. Index a ete mis au point. Il confirme que la transmission par x. Index passe par une retention specifique du virus dans le nematode. L'utilisation des isolats recombinants ecarte l'intervention de l'arn satellite des nepovirus et montre que la proteine 2b#m#p n'est pas responsable de la specificite de transmission.
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Vaysse, Laurence. "Développement de vecteurs non viraux pour le transfert de gène dans l'épithélium respiratoire". Bordeaux 2, 2000. http://www.theses.fr/2000BOR28795.
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Doucet, Gilles. "Les vecteurs viraux pour le développement de thérapies géniques ex vivo dans les cellules du muscle squelettique humain". Master's thesis, Université Laval, 2007. http://hdl.handle.net/20.500.11794/19481.
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Venail, Frédéric. "Transfert d'ADN dans la cochlée de mammifère par vecteur adénoviral : mise au point technique vers un modèle de régénération de l'organe de Corti utilisant l'interférence ARN". Montpellier 1, 2008. http://www.theses.fr/2008MON1T024.
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Les surdités de perception résultent principalement de la destruction des cellules neurosensorielles de la cochlée, partie de l'oreille interne dédiée à l'audition. Ces pertes sont irréversibles chez le mammifère, car les cellules ciliées détruites ne sont pas renouvelées à partir de leurs cellules de soutien comme chez les oiseaux ou les reptiles. Chez ces animaux, la régénération des cellules ciliées est étroitement liée à la régulation de la cycline p27kip1. Le but de ce travail était de déterminer si l'inhibition de p27kip1 pouvait entraîner une division et une différenciation des cellules de soutien en cellules sensorielles. Dans une première partie, nous montrons que les vecteurs adénoviraux sont capables d'infecter bon nombre de types cellulaires dans la cochlée de rat in vitro et in vivo, dont les cellules ciliées et les cellules de soutien de l'organe de Corti. Les capacités d'infection de ces virus dépendant étroitement de la présence et des conditions d'accès aux récepteurs adénoviraux (CAR et intégrines αvβ3 et αvβ5) mais aussi de la perméabilité des membranes séparant les différents compartiments liquidiens de la cochlée. Dans une seconde partie, nous avons utilisé un vecteur adénoviral capable d'inhiber de façon inductible la synthèse de la protéine p27kip1 par un mécanisme d'interférence ARN. Nous avons pu observer in vitro des mitoses parmi les cellules de soutien postnatales de rat (Hensen, Deiters, et cellules bordantes). Certaines cellules semblaient capables de se différencier et de perdre leur phénotype de cellules de soutien au profit de marqueurs de cellules ciliées. Ce résultat démontre la première fois la possibilité d'induire un phénomène de régénération mitotique dans la cochlée de mammifère, ouvrant ainsi une voie prometteuse aux thérapies géniques des surdités.
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Léger, Psylvia. "Etude comparée de l'infection de cellules de l'hôte mammifère et de cellules du vecteur moustique par le virus de la Fièvre de la Vallée du Rift". Paris 7, 2009. http://www.theses.fr/2009PA077073.
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Le Virus de la Fièvre de la Vallée du Rift (VFVR) est un virus appartenant à la famille des Bunyaviridae et au genre Phlebovinis. Cet arbovirus, transmis par les moustiques, infecte l'homme et les ruminants et est à l'origine de nombreuses épidémies/épizooties. Le segment S utilise une stratégie ambisens afin de coder la nucléoprotéine N ainsi que la protéine non structurale NSs. Bien que le cycle viral soit exclusivement cytoplasmique, NSs forme des filaments nucléaires. Cette protéine est à l'origine d'au moins deux mécanismes délétères lors de l'infection de cellules de mammifère. En interagissant avec la sous-unité p44 du facteur général de transcription TFIIH, NSs induit progressivement l'inhibition de la transcription générale. De plus, nos résultats mettent en évidence la fonction d'antagoniste de l'interféron P (IFN(3) de cette protéine. Cette dernière interagit avec les protéines cellulaires SAP30, appartenant aux co-répresseurs, et le facteur de transcription YY1. Ces interactions sont à l'origine de l'inhibition de l'expression de l'IFNp. Contrairement à ce qui est observé chez le mammifère, l'infection de cellules de moustique semble asymptomatique. Afin de déterminer les événements moléculaires à l'origine de ce contraste frappant, nous avons étudié l'infection de cellules de moustique et montré la conservation des interactions entre NSs et les orthologues de p44 et de SAP30 dans ces cellules. Dans les cellules d'arthropode, le mécanisme d'inhibition transcriptionnelle est semblable à celui observé dans les cellules murines. Toutefois, la protéine NSs est progressivement éliminée, ce qui entraîne la levée de l'inhibition délétèreThe Rift Valley Fever Virus (RVFV) is an arbovirus transmitted by mosquitoes to humans and livestock that causes dramatic epidemies and epizootics. As a member of the Phlebovirus genus of the Bunyaviridae family, the short segment (S) of its genome has an ambisens coding strategy for the nucleoprotein N and the non structural protein NSs. The later present an unusual localization to the nucleus, where it forms filamentous structures in mammalian cells. Through the interaction with several cellular factors, the NSs protein can be considered as a virulent factor. Interaction of NSs with p44, a subunit of the general transcription factor TFIIH, induces a progressive inhibition of the cellular RNA synthesis. NSs is also responsible of a specific inhibition of the interferon (3 (IFN(3) pathway when interacting with SAP30 and the transcription factor YY1, both required for the cell antiviral response. Contrary to mammals, the infection of mosquito cells by the RVFV remains asymptomatic. As the filamentous structure in the nucleus vanishes early after infection of mosquito cells, we analyzed the interaction of the NSs protein with the mosquito orthologs of the p44 and SAP30. A transient shutoff of the transcription is associated when NSs is present in the nucleus of mosquito cells, whereas the cleafance of NSs correlates with RNA synthesis restoration. These findings highlight the role of the NSs protein for differential pathogenesis observed between arthropod and mammal
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Lourenco, Sofia. "Etude de la modulation de la traduction du virus de l'hépatite C par des facteurs viraux en cis et en trans et développement de nouveaux outils via le système lentiviral". Paris 6, 2008. http://www.theses.fr/2008PA066333.
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Le virus de l’hépatite C (VHC) est actuellement responsable d’un problème de santé mondiale infectant environ 3% de la population. Le VHC possède une molécule d’ARN simple brin et de polarité positive ainsi que deux régions non codantes (NC) 5’ et 3’. La traduction virale a lieu via une séquence interne d’entrée des ribosomes (IRES) située dans la région 5’NC. L’objectif de ce travail de thèse a été de clarifier le rôle de facteurs viraux en cis (3’NC) et en trans (C, NS5A, NS5B) dans la régulation de l’activité traductionnelle de l’IRES. Nous avons utilisé un système double rapporteur ARN, ciblant ainsi la traduction. D’après l’activité relative de l’IRES mesurée (rapport RLuc/FLuc) différents points ont été observés : 1) la région 3’NC stimule fortement l’activité IRES en cis, ce qui dépend de la structure secondaire globale; 2) une modulation dose et génotype dépendante de la traduction a été démontrée en présence de C et NS5B ; 3) aucun effet synergique n’a été observé entre les protéines virales ou entre les différents facteurs viraux. D’après ces résultats, les facteurs viraux étudiés agiraient de façon séquentielle pour moduler la traduction virale. Nous nous sommes ensuite focalisés sur le développement de nouveaux outils. Nous avons établi un système lentiviral bicistronique, qui s’est révélé efficace pour le criblage de drogues. Les expériences actuellement en cours visent l’établissement d’une lignée exprimant constitutivement l’ARN polymérase du phage T7 (T7 RNAp), permettant à la fois une analyse fine de la fonctionnalité de l’IRES, le criblage de drogues ainsi que l’étude d’autres virus, remplaçant le système vaccine couramment utiliséHepatitis C virus (HCV) is responsible of a major health problem, infecting 3% of world population. Hepatitis C Virus (HCV) possesses a positive single-stranded RNA genome with highly structured non coding (NC) regions at its extremities: 5’NC and 3’NC. Translation initiation of HCV RNA occurs via an Internal Ribosome Entry Site (IRES) located at its 5’end. Our aim was to clarify the role of cis (3’NCR) and trans (C, NS5A, NS5B) viral factors on the regulation of IRES activity. By the use of a dual RNA reporter system, targeting the translation step and avoiding the cryptic IRES promoter activity, relative IRES activities measured in luminometry (= RLuc/FLuc activities ratio) revealed the following features : 1) all the HCV 3’ non coding (NC) sequences tested highly stimulate in cis the IRES efficiency; 2) a dose and genotype dependent modulation of the translation in trans was shown with the capsid and NS5B ; and 3) not any cooperative effect could be obtained either between viral proteins, or in the presence of both cis and trans factors. Taking together these results encouraged us to propose a model in which the viral factors tested act sequentially to modulate viral translation and the switch to replication. We then focus on the development of novel tools for evaluating the IRES activity analysis. We established a bicistronic lentiviral system, which revealed efficient for drugs screening, however not adequate for a precise IRES activity analysis. Experiments actually in progress aim the precise analysis of IRES activity, drugs screening and in addition the study of other viruses, replacing the vaccine system currently used
Livros sobre o assunto "Vecteur viraux"
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Julien, Jennifer. Le clônage de la protéine virale CrmA dans un vecteur d'expression. Sudbury, Ont: Université Laurentienne, 2000.
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L, Hefferon Kathleen, ed. Virus expression vectors. Tribandrum: Transworld Research Network, 2007.
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Mukhopadhyay, S. Plant virus, vector epidemiology and management. Enfield, NH: Science Publishers, 2010.
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Mukhopadhyay, S. Plant virus, vector epidemiology and management. Enfield, NH: Science Publishers, 2010.
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Mukhopadhyay, S. Plant virus, vector epidemiology and management. Enfield, NH: Science Publishers, 2010.
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T, Plumb R., ed. Plant virus vector interactions. San Diego: Academic Press, 2002.
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Chan, C. K. Aphid-transmitted viruses and their vectors of the world. Vancouver: Research Branch, Agriculture Canada, 1991.
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International Symposium on Viruses with Fungal Vectors (1987 St. Andrews University). Viruses with fungal vectors. Wellesbourne, Warwick: Association of Applied Biologists, 1988.
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C, Asher M. J., Cooper J. I e Association of Applied Biologists, eds. Viruses with fungal vectors: Proceedings of a conference at the University of St. Andrews, 25-27 August, 1987. Wellesbourne, Warwick: Association of Applied Biologists, 1988.
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Danielová, Vlasta. Relationships of mosquitoes to Ťahyňa virus as determinant factors of its circulation in nature. Prague: Academia, Publishing House of the Czechoslovak Academy of Sciences, 1992.
Encontre o texto completo da fonteCapítulos de livros sobre o assunto "Vecteur viraux"
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Conzelmann, Karl-Klaus. "Reverse Genetics of Mononegavirales: The Rabies Virus Paradigm". In Sendai Virus Vector, 1–20. Tokyo: Springer Japan, 2013. http://dx.doi.org/10.1007/978-4-431-54556-9_1.
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Nagai, Yoshiyuki, e Atsushi Kato. "Sendai Virus Biology and Engineering Leading up to the Development of a Novel Class of Expression Vector". In Sendai Virus Vector, 21–68. Tokyo: Springer Japan, 2013. http://dx.doi.org/10.1007/978-4-431-54556-9_2.
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Iida, Akihiro, e Makoto Inoue. "Concept and Technology Underlying Sendai Virus (SeV) Vector Development". In Sendai Virus Vector, 69–89. Tokyo: Springer Japan, 2013. http://dx.doi.org/10.1007/978-4-431-54556-9_3.
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Wiegand, Marian, e Wolfgang J. Neubert. "Genome Replication-Incompetent Sendai Virus Vaccine Vector Against Respiratory Viral Infections That Is Capable of Eliciting a Broad Spectrum of Specific Immune Response". In Sendai Virus Vector, 91–126. Tokyo: Springer Japan, 2013. http://dx.doi.org/10.1007/978-4-431-54556-9_4.
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Seki, Sayuri, e Tetsuro Matano. "Development of Vaccines Using SeV Vectors Against AIDS and Other Infectious Diseases". In Sendai Virus Vector, 127–49. Tokyo: Springer Japan, 2013. http://dx.doi.org/10.1007/978-4-431-54556-9_5.
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Yonemitsu, Yoshikazu, Yasuji Ueda e Mamoru Hasegawa. "BioKnife, a Modified Sendai Virus, to Resect Malignant Tumors". In Sendai Virus Vector, 151–69. Tokyo: Springer Japan, 2013. http://dx.doi.org/10.1007/978-4-431-54556-9_6.
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Fusaki, Noemi, e Hiroshi Ban. "Induction of Human Pluripotent Stem Cells by the Sendai Virus Vector: Establishment of a Highly Efficient and Footprint-Free System". In Sendai Virus Vector, 171–83. Tokyo: Springer Japan, 2013. http://dx.doi.org/10.1007/978-4-431-54556-9_7.
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Yonemitsu, Yoshikazu, Takuya Matsumoto e Yoshihiko Maehara. "Gene Therapy for Peripheral Arterial Disease Using Sendai Virus Vector: From Preclinical Studies to the Phase I/IIa Clinical Trial". In Sendai Virus Vector, 185–99. Tokyo: Springer Japan, 2013. http://dx.doi.org/10.1007/978-4-431-54556-9_8.
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Díaz-Menéndez, Marta, e Clara Crespillo-Andújar. "The Vector". In Zika Virus Infection, 21–30. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-59406-4_4.
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Gulhan, Baris. "Biological Methods Used in Gene Therapy". In Gene Therapy, 39–63. Istanbul: Nobel Tip Kitabevleri, 2024. http://dx.doi.org/10.69860/nobel.9786053358824.3.
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Gene therapy is used to prevent or treat genetic diseases. To treat genetic diseases, transfer of genes that correct the effects of the mutation that causes the disease to the patient. In gene therapy, the therapeutic gene is transferred to target cells through a vector and viral vectors are most used. Retroviruses (lentiviruses), adenoviruses, adeno-associated viruses, and herpes virus vectors are common as viral vectors. In this section, biological methods used especially in gene therapy stages examined.
Trabalhos de conferências sobre o assunto "Vecteur viraux"
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Araujo, Carlos Soares, Marco Cristo e Rafael Giusti. "Predicting Music Popularity on Streaming Platforms". In Simpósio Brasileiro de Computação Musical. Sociedade Brasileira de Computação - SBC, 2019. http://dx.doi.org/10.5753/sbcm.2019.10436.
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Online streaming platforms have become one of the most important forms of music consumption. Most streaming platforms provide tools to assess the popularity of a song in the forms of scores and rankings. In this paper, we address two issues related to song popularity. First, we predict whether an already popular song may attract higher-than-average public interest and become “viral”. Second, we predict whether sudden spikes in public interest will translate into long-term popularity growth. We base our findings in data from the streaming platform Spotify and consider appearances in its “Most-Popular” list as indicative of popularity, and appearances in its “Virals” list as indicative of interest growth. We approach the problem as a classification task and employ a Support Vector Machine model built on popularity information to predict interest, and vice versa. We also verify if acoustic information can provide useful features for both tasks. Our results show that the popularity information alone is sufficient to predict future interest growth, achieving a F1-score above 90% at predicting whether a song will be featured in the “Virals” list after being observed in the “Most-Popular”.
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Mueller, Melanie, Ralf Amann, Thomas Feger e Hans-Georg Rammensee. "Abstract A170: The mode of action of Orf virus – a novel viral vector for therapeutic cancer vaccines". In Abstracts: CRI-CIMT-EATI-AACR Inaugural International Cancer Immunotherapy Conference: Translating Science into Survival; September 16-19, 2015; New York, NY. American Association for Cancer Research, 2016. http://dx.doi.org/10.1158/2326-6074.cricimteatiaacr15-a170.
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Tomilova, Yulia, Yulia Khvorostova, Mikhail Ivanov, Marina Mikhailenko, Elena Runkova, Viktoriia Makukha, Tatiana Komissarova e Eduard Agletidinov. "Complex PCR-diagnostics of respiratory infections in A children's hospital". In Proceedings of the International Congress Public Health - Achievements and Challenges, 72. Institute of Public Health of Serbia "Dr Milan Jovanović Batut", 2024. http://dx.doi.org/10.5937/batutphco24027t.
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Background: Accurate differential etiological diagnosis allows to select the right therapy or adjust the course of treatment. The aim of the study was to analyze the etiological structure of childhood respiratory infections of viral and bacterial origin using the PCR method. Methods and Objectives: Nasoropharyngeal swabs of children admitted to hospital with symptoms of respiratory disease were examined (n=1443). The analysis was carried out using kits for DNA/RNA extraction and PCR kits "RealBest" (AO "Vector-Best"), designed to detect DNA/RNA of influenza A and B viruses, parainfluenza types 1-4, respiratory syncytial virus (RSV), metapneumovirus, adenoviruses, coronaviruses, rhinoviruses, bocavirus, Streptococcus pneumoniae, Haemophilus influenzae, Pseudomonas aeruginosa, Klebsiella pneumoniae, Staphylococcus aureus, Mycoplasma pneumoniae, Chlamydophila pneumoniae, Bordetella spp., Fungi, Candida albicans, human DNA. Neisseria meningitidis, Streptococcus pyogenes, and Moraxella catarrhalis were detected using primers of our own design for scientific research only. Results: For influenza A, a characteristic seasonal peak was observed in December 2022. RSV, on the contrary, was detected throughout the entire observation period. In the spring, in addition to parainfluenza type 3, all other types of parainfluenza (1, 2 and 4) were encountered. In children of different ages RSV, rhinovirus and coronaviruses predominated in the youngest group (up to one year), rhinovirus, adenovirus and RSV in the 1-5-year group, rhinovirus, adenovirus and influenza B in older children (over 5 years). 16-36% of samples were virus-free. In 47-57%, only 1 virus was detected, in 16-23% - 2 viruses, in 1-5% - 3 viruses. Some viruses have been shown to associate with certain types of bacteria. Conclusions: The widespread prevalence of antibiotic resistance necessitates precise differentiation of the causative agent of infection to justify the prescription of antibacterial drugs and optimize management.
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Nurpeisova, Ainur, Zhandos Abay, Kamshat Shorayeva, Sandugash Sadikaliyeva, Bolat Yespembetov, Kuanish Jekebekov, Nazym Syrym et al. "Determining optimal conditions for growing recombinant vectors to be used in developing a bovine tuberculosis vaccine". In Research for Rural Development 2023 : annual 29th international scientific conference proceedings. Latvia University of Life Sciences and Technologies, 2023. http://dx.doi.org/10.22616/rrd.29.2023.013.
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Two recombinant influenza A virus vectors expressing the ESAT 6 and TB10.4 mycobacterial proteins from the nonstructural (NS) gene were constructed via reverse genetics technique to develop a specific means of prophylaxis for bovine tuberculosis. We experimented to determine optimal conditions for growing recombinant vectors in Vero cell culture and chick embryos. This study established that the maximum amount of virus builds up in a Vero cell culture with the Dulbecco′s Modified Eagle′s Medium (DMEM) serum-free medium. However, using cell culture to produce vector vaccines is labourintensive and inefficient. An alternative way, a traditional, time-tested technique, is provided by growing samples in chick embryos. One of the advantages of this technique is its affordability and availability, enabling easy scale-up of vaccine production. In the optimization experiments, the FLU-ΔNS_ESAT 6 and FLU-ΔNS_ТВ10.4 viruses constructed were inoculated into 10-day-old chick embryos. It was determined that the optimal incubation temperature that led to the highest virus build-up was 37 ± 0.5 °С. And the infectious activity level of the FLU-ΔNS_ESAT 6 recombinant vector was at 8.95 ± 0.07 log10EID50 0.2 cm-3, while that of the FLU-ΔNS_ТВ10.4 was at 9.20 ± 0.07 log10EID50 0.2 cm-3, what was provided by infectious doses of 1000–10000 EID50, which makes it possible to create a virus-containing material with a hemagglutination activity level of 1:64. The size of recombinant vector amplicons expressing proteins ТВ10.4 and ESAT 6 was 1170 bp and 1175 bp, respectively. Electron microscopy images confirm that the developed virions are morphologically similar to the avian influenza virus.
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Lessa, Ruan Teixeira, Daniel Pedrosa Cassiano, Yasmin Jawhari da Silva, Sebastião José de Almeida Júnior, Adrianny Freitas Teixeira, Ana Luíza Paes da Silveira, Antônio Henrique Roberti dos Santos et al. "Epidemiological study on hospitalizations for viral encephalitis in Brazil between january 2010 to december 2020". In XIII Congresso Paulista de Neurologia. Zeppelini Editorial e Comunicação, 2021. http://dx.doi.org/10.5327/1516-3180.561.
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Introduction: Viral encephalitis (VE) is an inflammation of the brain parenchyma that progresses to neurological dysfunction of infectious origin. It occurs after hematogenous dissemination into the Central Nervous System and the most common agents are herpes virus, influenza, enterovirus, arbovirus, cytomegalovirus and Epstein-Barr. The signs and symptoms are headache, fever, decreased level of consciousness, seizures, focal deficits and behavioral changes. Objective: Recognize the epidemiological pattern of hospitalizations for VE in Brazil, between 2010 and 2020. Methods: A search for original articles and statistical information was performed in the databases Scielo, PUBMED, Medline and DATASUS, the latter related hospitalizations for VE with region, age, gender and year. Results: Hospitalizations are greater between 0 and 14 Y.O. (59.6%) in both genders, being 1.38M: 1F. The data indicate: <1 Y.O. (15%), 1-4 Y.O. (18.1%), 5-9 Y.O. (16.2%), 10-14 Y.O. (10.2%), totalizing 59.5% (21,004) of hospitalizations (35,188) in these groups, also intensified, between 20-29 Y.O., with 3,956 cases (11.2%). Comparing 2010 and 2020 there was a 63.4% reduction in hospitalizations for VE and the Southeast had the highest rate of the disease (42.1%). Conclusion: The epidemiological pattern of VE in the last decade represented higher prevalence in the interval between 0 and 14 Y.O.; mainly from 1 to 4. The decrease in the last 11 years may be due to adherence to vaccination campaigns and increased vector control, while the hypothesis for the higher incidence in the Southeast is because it is the most populous region, with favorable geographical areas for viral dissemination.
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Chisholm, Paul Joseph. "Competition with non-vectors mediates virus-vector interactions". In 2016 International Congress of Entomology. Entomological Society of America, 2016. http://dx.doi.org/10.1603/ice.2016.115741.
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Zhu, Richard, e Sujata Bhatia. "Optimizing COVID-19 Vaccine Diffusion in Respiratory Mucosa through Stokes-Einstein Modeling". In 2022 Design of Medical Devices Conference. American Society of Mechanical Engineers, 2022. http://dx.doi.org/10.1115/dmd2022-1065.
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Abstract SARS-COV-2 vaccines, all of which are currently intramuscular shots, have the ability to prevent serious injury. However, the absence of sufficient mucosal immunity is a major concern. To counteract this deficiency that has led to continued transmission from vaccinated individuals and breakthrough cases, reformulating vaccines to be inhalable presents a logical administration route. Predecessor research has reported the inhalable route to be viable as aerosolized vaccine nanoparticles, AAV phage nanoparticles, and PIV-5 viruses were recently identified to elicit immune responses. In this study, the diffusion of vaccine nanoparticles across the mucosa is characterized and modeled, with respect to their observed behavior from previous studies in relation to the Stokes-Einstein equation, to predict the most efficient model of an inhalable COVID-19 vaccine. The Stokes-Einstein equation has been used in several studies to predict diffusion coefficients. These predictions may be modified to fit the specifications of mucosal interactions. It was determined that mucosal interactions play a significant role in vaccine nanoparticle diffusion, as demonstrated by the viral vector and virus-like nanoparticle diffusion, and can be characterized by an equivalent hydrodynamic radius. Moreover, as a counter to mucosal interactions, PEGylation was found to drastically decrease the viscous slowing of the mucus medium.
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de Souza, Laise Novellino Nunes, Wagner Rambaldi Telles e Jader Lugon Junior. "Analysis of legislation relating to vectors and management of urban floods in the state of Rio de Janeiro". In ENSUS 2024 - XII Encontro de Sustentabilidade em Projeto, 178–88. Grupo de Pesquisa Virtuhab/UFSC, 2024. http://dx.doi.org/10.29183/2596-237x.ensus2024.v12.n1.p178-188.
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Dengue is a worldwide disease that has spread in several states in Brazil and, in particular, in the state of Rio de Janeiro. In the forest environment, fish play the role of reducing the mosquito population in the initial phase, and lizards and frogs in the adult phase. In cities, mosquitoes function as urban pests, that is, they have an uncontrolled population due to the lack of natural predators, in addition to the availability of environment and food for their growth and reproduction. It is worth highlighting the fact that basic sanitation is not universal for populations, and even less is it considered as an investment factor to combat vectors that transmit dengue fever, despite the mosquito's first stage of development being in water. The objective of this work is to bring, through a bibliographical review, all the legislation applied to combat the dengue virus, which is also a vector of the zika virus and the chickunguya virus in the state of Rio de Janeiro, as well as to analyze which regulations include basic sanitation as a measure to contain the spread of the disease. Among 92 (ninety-two) municipalities in the state of Rio de Janeiro, only 13 (thirteen) municipalities approved decrees and/or laws that address the fight against the mosquito that transmits dengue, zika virus and chikungunya, and only the city of São Gonçalo mentioned care with drainage on public roads. This study demonstrates how there is a gap in combating the vector that transmits dengue when it comes to basic sanitation.
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Redinbaugh, Margaret (Peg). "Vector-virus interactions in maize agroecosystems in East Africa". In 2016 International Congress of Entomology. Entomological Society of America, 2016. http://dx.doi.org/10.1603/ice.2016.94561.
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Raafat, Nermin, Chantal Mengus, Michael Heberer, Giulio C. Spagnoli e Paul Zajac. "Abstract 1500: Modulation of recombinant vaccinia virus vector immunogenicity". In Proceedings: AACR 101st Annual Meeting 2010‐‐ Apr 17‐21, 2010; Washington, DC. American Association for Cancer Research, 2010. http://dx.doi.org/10.1158/1538-7445.am10-1500.
Texto completo da fonteRelatórios de organizações sobre o assunto "Vecteur viraux"
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Ullman, Diane, James Moyer, Benjamin Raccah, Abed Gera, Meir Klein e Jacob Cohen. Tospoviruses Infecting Bulb Crops: Evolution, Diversity, Vector Specificity and Control. United States Department of Agriculture, setembro de 2002. http://dx.doi.org/10.32747/2002.7695847.bard.
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Objectives. The overall goal of the proposed research was to develop a mechanistic understanding of tospovirus evolution, diversity and vector specificity that could be applied to development of novel methods for limiting virus establishment and spread. Our specific objectives were: 1) To characterize newly intercepted tospoviruses in onion, Hippeastrum and other bulb crops and compare them with the known tomato spotted wilt virus (TSWV) and its isolates; 2) To characterize intra- and interspecific variation in the virus transmission by thrips of the new and distinct tospoviruses. and, 3) To determine the basis of vector specificity using biological, cellular and molecular approaches. Background. New tospoviruses infecting bulb crops were detected in Israel and the US in the mid-90s. Their plant host ranges and relationships with thrips vectors showed they differed from the type member of the Tospovirus genus, tomato spotted wilt virus (TSWV). Outbreaks of these new viruses caused serious crop losses in both countries, and in agricultural and ornamental crops elsewhere. In the realm of plant infecting viruses, the tospoviruses (genus: Tospovirus , family: Bunyaviridae ) are among the most aggressive emerging viruses. Tospoviruses are transmitted by several species of thrips in a persistent, propagative fashion and the relationships between the viruses and their thrips vectors are often specific. With the emergence of new tospoviruses, new thrips vector/tospovirus relationships have also arisen and vector specificities have changed. There is known specificity between thrips vector species and particular tospoviruses, although the cellular and molecular bases for this specificity have been elusive. Major conclusions, solutions and achievements. We demonstrated that a new tospovirus, iris yellow spot virus (IYSV) caused "straw bleaching" in onion (Allium cepa) and lisianthus necrosis in lisianthus (Eustoma russellianum). Characterization of virus isolates revealed genetic diversity among US, Brazilian, Dutch and Israeli isolates. IYSV was not seed transmitted, and in Israel, was not located in bulbs of infected plants. In the US, infected plants were generated from infected bulbs. The relationship between IYSV and Thrips tabaci was shown to be specific. Frankliniella occidentalis, the primary vector of many other tospoviruses, did not transmit IYSV isolates in Israel or the US. Furthermore, 1': tabaci populations varied in their transmission ability. Transmission was correlated to IYSV presence in thrips salivary glands. In Israel, surveys in onion fields revealed that the onion thrips, Thrips tabaci Lindeman was the predominant species and that its incidence was strongly related to that of IYSV infection. In contrast, in the U.S., T. tabaci and F. occidentalis were present in high numbers during the times sampled. In Israel, insecticides reduced onion thrips population and caused a significant yield increase. In the US, a genetic marker system that differentiates non-thrips transmissible isolates from thrips transmissible isolate demonstrated the importance of the M RNA to thrips transmission of tospoviruses. In addition, a symbiotic Erwinia was discovered in thrips and was shown to cause significant artifacts in certain types of virus binding experiments. Implications, scientific and agricultural. Rapid emergence of distinct tospoviruses and new vector relationships is profoundly important to global agriculture. We advanced the understanding of IYSV in bulb crops and its relationships with thrips vector species. The knowledge gained provided growers with new strategies for control and new tools for studying the importance of particular viral proteins in thrips specificity and transmission efficiency.
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Mawassi, Munir, e Valerian V. Dolja. Role of the viral AlkB homologs in RNA repair. United States Department of Agriculture, junho de 2014. http://dx.doi.org/10.32747/2014.7594396.bard.
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AlkB proteins that repair DNA via reversing methylation damage are conserved in a broad range of prokaryotes and eukaryotes including plants. Surprisingly, AlkB-domains were discovered in the genomes of numerous plant positive-strand RNA viruses, majority of which belong to the family Flexiviridae. The major goal of this research was to reveal the AlkB functions in the viral infection cycle using a range of complementary genetic and biochemical approaches. Our hypotheses was that AlkB is required for efficient replication and genetic stability of viral RNA genomes The major objectives of the research were to identify the functions of GVA AlkB domain throughout the virus infection cycle in N. benthamiana and grapevine, to investigate possible RNA silencing suppression activity of the viral AlkBs, and to characterize the RNA demethylation activity of the mutated GVA AlkBs in vitro and in vivo to determine methylation status of the viral RNA. Over the duration of project, we have made a very substantial progress with the first two objectives. Because of the extreme low titer of the virus particles in plants infected with the AlkB mutant viruses, we were unable to analyze RNA demethylation activity and therefore had to abandon third objective. The major achievements with our objectives were demonstration of the AlkB function in virus spread and accumulation in both experimental and natural hosts of GVA, discovery of the functional cooperation and physical interaction between AlkB and p10 AlkB in suppression of plant RNA silencing response, developing a powerful virus vector technology for grapevine using GLRaV-2-derived vectors for functional genomics and pathogen control in grapevine, and in addition we used massive parallel sequencing of siRNAs to conduct comparative analysis of the siRNA populations in grape plants infected with AlkB-containing GLRaV-3 versus GLRaV-2 that does not encode AlkB. This analysis revealed dramatically reduced levels of virus-specific siRNAs in plants infected with GLRaV-3 compared to that in GLRaV-2 infection implicating AlkB in suppression of siRNA formation. We are pleased to report that BARD funding resulted in 5 publications directly supported by BARD, one US patent, and 9 more publications also relevant to project. Moreover, two joint manuscripts that summarize work on GVA AlkB (led by Israeli PI) and on viral siRNAs in grapevine (led by US PI in collaboration with University of Basel) are in preparation.
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Mawassi, Munir, Adib Rowhani, Deborah A. Golino, Avichai Perl e Edna Tanne. Rugose Wood Disease of Grapevine, Etiology and Virus Resistance in Transgenic Vines. United States Department of Agriculture, novembro de 2003. http://dx.doi.org/10.32747/2003.7586477.bard.
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Rugose wood is a complex disease of grapevines, which occurs in all growing areas. The disease is spread in the field by vector transmission (mealybugs). At least five elongated-phloem- limited viruses are implicated in the various rugose wood disorders. The most fully characterized of these are Grapevine virus A (GV A) and GVB, members of a newly established genus, the vitivirus. GVC, a putative vitivirus, is much less well characterized than GV A or GVB. The information regarding the role of GVC in the etiology and epidemiology of rugose wood is fragmentary and no sequence data for GVC are available. The proposed research is aimed to study the etiology and epidemiology of rugose wood disease, and to construct genetically engineered virus-resistant grapevines. The objectives of our proposed research were to construct transgenic plants with coat protein gene sequences designed to induce post-transcriptional gene silencing (pTGS); to study the epidemiology and etiology of rugose wood disease by cloning and sequencing of GVC; and surveying of rugose wood- associated viruses in Californian and Israeli vineyards. In an attempt to experimentally define the role of the various genes of GV A, we utilized the infectious clone, inserted mutations in every ORF, and studied the effect on viral replication, gene expression, symptoms and viral movement. We explored the production of viral RNAs in a GV A-infected Nicotiana benthamiana herbaceous host, and characterized one nested set of three 5'-terminal sgRNAs of 5.1, 5.5 and 6.0 kb, and another, of three 3'-terminal sgRNAs of 2.2, 1.8 and 1.0 kb that could serve for expression of ORFs 2-3, respectively. Several GV A constructs have been assembled into pCAMBIA 230 I, a binary vector which is used for Angrobacterium mediated transformation: GV A CP gene; two copies of the GV A CP gene arranged in the same antisense orientation; two copies of the GV A CP gene in which the downstream copy is in an antigens orientation; GV A replicase gene; GV A replicase gene plus the 3' UTR sequence; and the full genome of GV A. Experiments for transformation of N. benthamiana and grapevine cell suspension with these constructs have been initiated. Transgenic N. benthamiana plants that contained the CP gene, the replicase gene and the entire genome of GV A were obtained. For grapevine transformation, we have developed efficient protocols for transformation and successfully grapevine plantlets that contained the CP gene and the replicase genes of GV A were obtained. These plants are still under examination for expression of the trans genes. The construction of transgenic plants with GV A sequences will provide, in the long run, a means to control one of the most prevalent viruses associated with grapevines. Our many attempts to produce a cDNA library from the genome of GVC failed. For surveying of rugose wood associated viruses in California vineyards, samples were collected from different grape growing areas and tested by RT-PCR for GV A, GVB and GVD. The results indicated that some of the samples were infected with multiple viruses, but overall, we found higher incidence of GVB and GV A infection in California vineyards and new introduction varieties, respectively. In this research we also conducted studies to increase our understanding of virus - induced rootstock decline and its importance in vineyard productivity. Our results provided supporting evidence that the rootstock response to virus infection depends on the rootstock genotype and the virus type. In general, rootstocks are differ widely in virus susceptibility. Our data indicated that a virus type or its combination with other viruses was responsible in virus-induced rootstock decline. As the results showed, the growth of the rootstocks were severely affected when the combination of more than one virus was present.
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Ullman, Diane E., Benjamin Raccah, John Sherwood, Meir Klein, Yehezkiel Antignus e Abed Gera. Tomato Spotted Wilt Tosporvirus and its Thrips Vectors: Epidemiology, Insect/Virus Interactions and Control. United States Department of Agriculture, novembro de 1999. http://dx.doi.org/10.32747/1999.7573062.bard.
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Objectives. The major aim of the proposed research was to study thrips-TSWV relationships and their role in the epidemiology of the virus with the aim of using this knowledge to reduce crop losses occurring due to epidemics. Our specific objectives were: To determine the major factors involved in virus outbreaks, including: a) identifying the thrips species involved in virus dissemination and their relative role in virus spread; b) determining the virus sources among wild and cultivated plants throughout the season and their role in virus spread, and, c) determining how temperature and molecular variations in isolates impact virus replication in plants and insects and impact the transmission cycle. Background to the topic. Tospoviruses are among the most important emerging plant viruses that impact production of agricultural and ornamental crops. Evolution of tospoviruses and their relationships with thrips vector species have been of great interest because of crop damage caused world wide and the complete absence of suitable methods of control. Tospoviruses threaten crops in Israel and the United States. By understanding the factors contributing to epidemics and the specific relationships between thrips species and particular tospoviruses we hope that new strategies for control can be developed that will benefit agriculture in both Israel and the United States. Major conclusions, solutions, achievements. We determined that at least three tospoviruses were involved in epidemics in Israel and the United States, tomato spotted wilt virus (TSWV), impatiens necrotic spot virus (INSV) and iris yellow spot virus (IYSV). We detected and characterized INSV for the first time in Israel and, through our efforts, IYSV was detected and characterized for the first time in both countries. We demonstrated that many thrips species were present in commercial production areas and trap color influenced thrips catch. Frankliniella occidentalis was the major vector species of INSV and TSWV and populations varied in transmission efficiency. Thrips tabaci is the sole known vector of IYSV and experiments in both countries indicated that F. occidentalis is not a vector of this new tospovirus. Alternate plant hosts were identified for each virus. A new monitoring system combining sticky cards and petunia indicator plants was developed to identify sources of infective thrips. This system has been highly successful in the U.S. and was used to demonstrate to growers that removal of plant sources of infective thrips has a dramatic impact on virus incidence. Finally, a putative thrips receptor mediating acquisition of TSWV was discovered. Implications, scientific and agricultural. Our findings have contributed to new control measures that will benefit agriculture. Identification of a putative thrips receptor for TSWV and our findings relative to thrips/tospovirus specificity have implications for development of innovative new control strategies.
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Grubman, Marvin J., Yehuda Stram, Peter W. Mason e Hagai Yadin. Development of an Empty Viral Capsid Vaccine against Foot and Mouth Disease. United States Department of Agriculture, agosto de 1995. http://dx.doi.org/10.32747/1995.7570568.bard.
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Foot-and-mouth disease (FMD), a highly infectious viral disease of cloven-hoofed animals, is economically the most important disease of domestic animals. Although inactivated FMD vaccines have been succesfully used as part of comprehensive eradication programs in Western Europe, there are a number of concerns about their safety. In this proposal, we have attempted to develop a new generation of FMD vaccines that addresses these concerns. Specifically we have cloned the region of the viral genome coding for the structural proteins and the proteinase responsible for processing of the structural protein precursor into both a DNA vector and a replication-deficient human adenovirus. We have demonstrated the induction of an FMDV-specific immune response and a neutralizing antibody response with the DNA vectors in mice, but preliminary potency and efficacy studies in swine are variable. However, the adenovirus vector induces a significant and long-lived neutralizing antibody response in mice and most importantly a neutralizing and protective response in swine. These results suggest that the empty capsid approach is a potential alternative to the current vaccination strategy.
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Antignus, Yehezkiel, Ernest Hiebert, Shlomo Cohen e Susan Webb. Approaches for Studying the Interaction of Geminiviruses with Their Whitefly Vector Bemisia tabaci. United States Department of Agriculture, julho de 1995. http://dx.doi.org/10.32747/1995.7604928.bard.
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The DNA of tomato yellow leaf curl virus (TYLCB) was detected in its whitefly vector, Bemisia tabaci, by dot spot hybridization as early as 1 h after acquisition access. The retention of the virus nucleic acid in the vector was at least 23 days after a 48 h acquisition access. However, the retention of TYLCV coat protein did not exceed 10 days. No replicative forms of TYLCV could be detected in B. tabaci, indicating a non-propagative relationship with the vector. Whiteflies were not able to accumulate naked virion ssDNA, virus cloned dsDNA, or virions with impaired coat protein. Deletion, frameshift, and single amino acid mutations were inserted into open reading frames (ORFs) V1 and V2 (Coat protein) of TYLCV. The ability of these mutants to replicate, to spread and to induce symptoms was tested both in leaf disks and in intact plants. No replication was found in tissues that were infected with a deletion mutant that lacked the carboxy half of the coat protein gene. Residual amounts of ssDNA and dsDNA were detected i tissues infected with a frameshift mutant in which an early termination at the extreme part of the protein. Two other mutants in which a single amino acid was changed in the overlapping part of V1 and V2 were able to spread systemically but infections remained symptomless and the production of ssDNA and dsDNA were significantly lower. These mutants were acquired and transmitted by Bemisia tabaci. Procedures for the the dissection, fixation and embedding of whiteflies were developed. The anatomy and ultrastructure of the salivary gland and the midgut of Bemisia tabaci and Trialeurodes vaporariorum (a vector and non-vector of geminiviruses respectively) was studied and described. Monoclonal antibodies against bean golden mosaic virus (BGMV) with narrow and broad spectrum were prepared. Transmission studies of tomato mottle geminivirus (TMoV) by B. tabaci were carried out. These studies were essential for a further work aimed to understand the interaction of geminiviruses with the insect and their localization in its tissues. To enable the production of transgenic plants procedures were developed for tomato transformation with both Agrobacterium and microparticle bombardment.
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Hernández Guzmán, Anngie Katherine, Diana Marcela Torres Jiménez e Olga Yanet Pérez Cardona. Effect of the acquisition access period, retention period and inoculation access period on transmission efficiency of Potato yellow vein virus by Trialeurodes vaporariorum. Corporación Colombiana de Investigación Agropecuaria - AGROSAVIA, 2013. http://dx.doi.org/10.21930/agrosavia.poster.2013.1.
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El virus de la vena amarilla de la papa (PYVV) (Crinivirus / Closteroviridae), es un virus de planta reemergente, que se extendió en todas las áreas de de producción de papa colombiana PYVV, este es transmitido por el invernadero de mosca blanca (Trialeurodes vaporariorum) de semipersistente. Para la implementación de estrategias efectivas para PYVV / T. y el control de vaporariorum es necesaria la información sobre la relación entre el virus y su vector. En el presente estudio se detalla la transmisión de PYVV, se presentan las características de T. vaporariorum, la adquisición del período de acceso (AAP), período de retención (RP) e inoculación y el período de acceso (IAP) evaluado
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Mawassi, Munir, Baozhong Meng e Lorne Stobbs. Development of Virus Induced Gene Silencing Tools for Functional Genomics in Grapevine. United States Department of Agriculture, julho de 2013. http://dx.doi.org/10.32747/2013.7613887.bard.
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Grapevine is perhaps the most widely grown fruit crop. To understand the genetic make-up so as to improve the yield and quality of grapes and grape products, researchers in Europe have recently sequenced the genomes of Pinot noir and its inbred. As expected, function of many grape genes is unknown. Functional genomics studies have become the major focus of grape researchers and breeders. Current genetic approaches for gene function studies include mutagenesis, crossing and genetic transformation. However, these approaches are difficult to apply to grapes and takes long periods of time to accomplish. It is thus imperative to seek new ways for grape functional genomics studies. Virus-induced gene silencing (VIGS) offers an attractive alternative for this purpose and has proven highly effective in several herbaceous plant species including tomato, tobacco and barley. VIGS offers several advantages over existing functional genomics approaches. First, it does not require transformation to silence a plant gene target. Instead, it induces silencing of a plant gene through infection with a virus that contains the target gene sequence, which can be accomplished within a few weeks. Second, different plant genes can be readily inserted into the viral genome via molecular cloning and functions of a large number of genes can be identified within a short period of time. Our long-term goal of this research is to develop VIGS-based tools for grapevine functional genomics, made of the genomes of Grapevine virus A (GVA) from Israel and Grapevine rupestris stem pitting-associated virus (GRSPaV) from Canada. GVA and GRSPaV are members of the Flexiviridae. Both viruses have single-stranded, positive sense RNA genomes, which makes them easy to manipulate genetically and excellent candidates as VIGS vectors. In our three years research, several major breakthroughs have been made by the research groups involved in this project. We have engineered a cDNA clone of GVA into a binary vector that is infectious upon delivery into plantlets of micropropagated Vitis viniferacv. Prime. We further developed the GVA into an expression vector that successfully capable to silence endogenous genes. We also were able to assemble an infectious full-length cDNA clones of GRSPaV. In the following sections Achievements and Detailed description of the research activities, we are presenting the outcome and results of this research in details.
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Klement, Eyal, Elizabeth Howerth, William C. Wilson, David Stallknecht, Danny Mead, Hagai Yadin, Itamar Lensky e Nadav Galon. Exploration of the Epidemiology of a Newly Emerging Cattle-Epizootic Hemorrhagic Disease Virus in Israel. United States Department of Agriculture, janeiro de 2012. http://dx.doi.org/10.32747/2012.7697118.bard.
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In September 2006 an outbreak of 'Bluetongue like' disease struck the cattle herds in Israel. Over 100 dairy and beef cattle herds were affected. Epizootic hemorrhagic disease virus (EHDV) (an Orbivirusclosely related to bluetongue virus (BTV)), was isolated from samples collected from several herds during the outbreaks. Following are the aims of the study and summary of the results: which up until now were published in 6 articles in peer-reviewed journals. Three more articles are still under preparation: 1. To identify the origin of the virus: The virus identified was fully sequenced and compared with the sequences available in the GenBank. It appeared that while gene segment L2 was clustered with EHDV-7 isolated in Australia, most of the other segments were clustered with EHDV-6 isolates from South-Africa and Bahrain. This may suggest that the strain which affected Israel on 2006 may have been related to similar outbreaks which occurred in north-Africa at the same year and could also be a result of reassortment with an Australian strain (Wilson et al. article in preparation). Analysis of the serological results from Israel demonstrated that cows and calves were similarly positive as opposed to BTV for which seropositivity in cows was significantly higher than in calves. This finding also supports the hypothesis that the 2006 EHD outbreak in Israel was an incursive event and the virus was not present in Israel before this outbreak (Kedmi et al. Veterinary Journal, 2011) 2. To identify the vectors of this virus: In the US, Culicoides sonorensis was found as an efficient vector of EHDV as the virus was transmitted by midges fed on infected white tailed deer (WTD; Odocoileusvirginianus) to susceptible WTD (Ruder et al. Parasites and Vectors, 2012). We also examined the effect of temperature on replication of EHDV-7 in C. sonorensis and demonstrated that the time to detection of potentially competent midges decreased with increasing temperature (Ruder et al. in preparation). Although multiple attempts were made, we failed to evaluate wild-caught Culicoidesinsignisas a potential vector for EHDV-7; however, our finding that C. sonorensis is a competent vector is far more significant because this species is widespread in the U.S. As for Israeli Culicoides spp. the main species caught near farms affected during the outbreaks were C. imicolaand C. oxystoma. The vector competence studies performed in Israel were in a smaller scale than in the US due to lack of a laboratory colony of these species and due to lack of facilities to infect animals with vector borne diseases. However, we found both species to be susceptible for infection by EHDV. For C. oxystoma, 1/3 of the Culicoidesinfected were positive 11 days post feeding. 3. To identify the host and environmental factors influencing the level of exposure to EHDV, its spread and its associated morbidity: Analysis of the cattle morbidity in Israel showed that the disease resulted in an average loss of over 200 kg milk per cow in herds affected during September 2006 and 1.42% excess mortality in heavily infected herds (Kedmi et al. Journal of Dairy Science, 2010). Outbreak investigation showed that winds played a significant role in virus spread during the 2006 outbreak (Kedmi et al. Preventive Veterinary Medicine, 2010). Further studies showed that both sheep (Kedmi et al. Veterinary Microbiology, 2011) and wild ruminants did not play a significant role in virus spread in Israel (Kedmi et al. article in preparation). Clinical studies in WTD showed that this species is highly susceptibile to EHDV-7 infection and disease (Ruder et al. Journal of Wildlife Diseases, 2012). Experimental infection of Holstein cattle (cows and calves) yielded subclinical viremia (Ruder et al. in preparation). The findings of this study, which resulted in 6 articles, published in peer reviewed journals and 4 more articles which are in preparation, contributed to the dairy industry in Israel by defining the main factors associated with disease spread and assessment of disease impact. In the US, we demonstrated that sufficient conditions exist for potential virus establishment if EHDV-7 were introduced. The significant knowledge gained through this study will enable better decision making regarding prevention and control measures for EHDV and similar viruses, such as BTV.
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Durden, Lance A., Thomas M. Logan, Mark L. Wilson e Kenneth J. Linthicum. Experimental Vector Incompetence of a Soft Tick, Ornithodoros sonrai (Acari: Argasidae), for Crimean-Congo Hemorrhagic Fever Virus. Fort Belvoir, VA: Defense Technical Information Center, janeiro de 1993. http://dx.doi.org/10.21236/ada265568.
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