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Sample records for contre le virus

  1. Le contrôle des infections au cabinet du pédiatre

    PubMed Central

    2008-01-01

    RÉSUMÉ La transmission des infections au cabinet du pédiatre est de plus en plus préoccupante. Le présent document expose les voies de transmission des infections et les principes sous-jacents aux mesures actuelles pour contrôler les infections. Pour prévenir les infections, il faut bien concevoir le cabinet et adopter des politiques administratives et de triage convenables, de même que des pratiques de base pour les soins de tous les patients (p. ex., hygiène des mains, port de gants, de masques, de lunettes de protection et d’une blouse d’hôpital pour des interventions précises; nettoyage, désinfection et stérilisation convenables des surfaces et du matériel, y compris les jouets, et techniques d’asepsie en cas d’interventions effractives) et des précautions additionnelles en cas d’infections précises. Le personnel doit avoir reçu les vaccins pertinents, et les personnes infectées doivent respecter les politiques de restriction au travail.

  2. Mise à jour sur le nouveau vaccin 9-valent pour la prévention du virus du papillome humain

    PubMed Central

    Yang, David Yi; Bracken, Keyna

    2016-01-01

    Résumé Objectif Informer les médecins de famille quant à l’efficacité, à l’innocuité, aux effets sur la santé publique et à la rentabilité du vaccin 9-valent contre le virus du papillome humain (VPH). Qualité des données Des articles pertinents publiés dans PubMed jusqu’en mai 2015 ont été examinés et analysés. La plupart des données citées sont de niveau I (essais randomisés et contrôlés et méta-analyses) ou de niveau II (études transversales, cas-témoins et épidémiologiques). Des rapports et recommandations du gouvernement sont aussi cités en référence. Message principal Le vaccin 9-valent contre le VPH, qui offre une protection contre les types 6, 11, 16, 18, 31, 33, 45, 52 et 58 du VPH, est sûr et efficace et réduira encore plus l’incidence des infections à VPH, de même que les cas de cancer lié au VPH. Il peut également protéger indirectement les personnes non immunisées par l’entremise du phénomène d’immunité collective. Un programme d’immunisation efficace peut prévenir la plupart des cancers du col de l’utérus. Les analyses montrent que la rentabilité du vaccin 9-valent chez les femmes est comparable à celle du vaccin quadrivalent original contre le VPH (qui protège contre les types 6, 11, 16 et 18 du VPH) en usage à l’heure actuelle. Toutefois, il faut investiguer plus en profondeur l’utilité d’immuniser les garçons avec le vaccin 9-valent contre le VPH. Conclusion en plus d’être sûr, le vaccin 9-valent protège mieux contre le VPH que le vaccin quadrivalent. Une analyse coûtefficacité en favorise l’emploi, du moins chez les adolescentes. Ainsi, les médecins devraient recommander le vaccin 9-valent à leurs patients plutôt que le vaccin quadrivalent contre le VPH.

  3. Contrôle de l'orientation et de l'alignement moléculaire par un train d'impulsions soudaines

    NASA Astrophysics Data System (ADS)

    Sugny, D.

    2006-10-01

    Les récents progrès technologiques dans le domaine des Lasers permettent d'envisager le contrôle de nombreux processus quantiques jouant un rôle dans une variété de problèmes s'étendant de la réactivité chimique à l'information quantique. Dans ce contexte, nous nous sommes intéressés au contrôle de l'orientation ou de l'alignement moléculaire en utilisant un train d'impulsions soudaines. Nous avons défini des états cibles qui maximisent à la fois l'orientation ou l'alignement et sa durée dans le temps et montré comment atteindre ces états à l'aide de stratégie systématique ou optimisée

  4. Effets du stress familial lié au diabète sur le contrôle glycémique chez les jeunes diabétiques de type 1

    PubMed Central

    Tsiouli, Elina; Alexopoulos, Evangelos C.; Stefanaki, Charikleia; Darviri, Christina; Chrousos, George P.

    2013-01-01

    Objectif Examiner la façon dont le stress familial influence le contrôle glycémique chez les patients diabétiques de moins de 18 ans. Sources des données Une recherche des études pertinentes publiées depuis 1990 a été réalisée dans PubMed et Scopus à l'aide des mots-clés suivants en anglais: diabetes type 1, glycemic control, family stress, family conflict et family function. Sélection des études La recension initiale a permis de cerner un total de 1 478 articles. La synthèse finale portrait sur 6 études de cohortes, 3 études transversales et 1 étude qualitative dans lesquelles le stress familial était évalué à l'aide d'instruments de mesure des conflits spécifiquement reliés au diabète et le contrôle glycémique était mesuré en fonction de l'hémoglobine glycosylée. Synthèse Dans la plupart des études, il existait une corrélation négative entre le stress familial et le contrôle glycémique des patients. Le bon fonctionnement familial était fortement relié à un bon contrôle glycémique des patients, tandis que les conflits familiaux étaient associés à un mauvais contrôle glycémique. Les familles dont la situation socioéconomique était défavorisée, celles ayant des adolescents atteints de diabète et les familles monoparentales étaient plus enclines à vivre un stress relié au diabète et étaient, par conséquent, plus susceptibles de connaître un moins bon contrôle glycémique. Conclusion Les interventions psychologiques thérapeutiques et les programmes éducatifs peuvent aider à atténuer le stress familial relié au diabète et amélioreront probablement le contrôle glycémique.

  5. Modelisation numerique et validation experimentale d'un systeme de protection contre le givre par elements piezoelectriques

    NASA Astrophysics Data System (ADS)

    Harvey, Derek

    Le degivrage au moyen d'actuateurs piezoelectriques est considere comme une avenue prometteuse pour le developpement de systemes a faible consommation d'energie applicables aux helicopteres legers. Ce type de systeme excite des frequences de resonances d'une structure pour produire des deformations suffisantes pour rompre l'adherence de la glace. Par contre, la conception de tel systeme demeure generalement mal comprise. Ce projet de maitrise etudie l'utilisation de methodes numeriques pour assister la conception des systemes de protection contre le givre a base d'elements piezoelectriques. La methodologie retenue pour ce projet a ete de modeliser differentes structures simples et de simuler l'excitation harmonique des frequences de resonance au moyen d'actuateurs piezoelectriques. Le calcul des frequences de resonances ainsi que la simulation de leur excitation a ensuite ete validee a l'aide de montages experimentaux. La procedure a ete realisee pour une poutre en porte-a-faux et pour une plaque plane a l'aide du logiciel de calcul par elements finis, Abaqus. De plus, le modele de la plaque plane a ete utilise afin de realiser une etude parametrique portant sur le positionnement des actuateurs, l'effet de la rigidite ainsi que de l'epaisseur de la plaque. Finalement, la plaque plane a ete degivree en chambre climatique. Des cas de degivrage ont ete simules numeriquement afin d'etudier la possibilite d'utiliser un critere base sur la deformation pour predire le succes du systeme. La validation experimentale a confirme la capacite du logiciel a calculer precisement a la fois les frequences et les modes de resonance d'une structure et a simuler leur excitation par des actuateurs piezoelectriques. L'etude revele que la definition de l'amortissement dans le modele numerique est essentiel pour l'obtention de resultats precis. Les resultats de l'etude parametrique ont demontre l'importance de minimiser l'epaisseur et la rigidite afin de reduire la valeur des frequences

  6. Le gingembre contre la nausée et les vomissements de la grossesse

    PubMed Central

    Lindblad, Adrienne J.; Koppula, Sudha

    2016-01-01

    Question clinique Le gingembre peut-il traiter la nausée et les vomissements de la grossesse? Résultats Durant le premier trimestre, le gingembre soulagerait la nausée et les vomissements de quelque 4 points sur une échelle de 40 points, ou éliminerait les vomissements chez 1 femme sur 3 au jour 6. L’étude la plus vaste ne laisse croire à aucune hausse des malformations congénitales ou de la mortinatalité, mais les études de moins grande envergure laissent croire le contraire.

  7. Contrôle d'une machine asynchrone par estimation robuste de la vitesse

    NASA Astrophysics Data System (ADS)

    Roboam, X.; Hapiot, J. C.; de Fornel, B.; Andrieux, C.

    1992-03-01

    This paper describes the study and the implementation of a variable speed drive for induction motor with no mechanical sensor. Power is supplied by a current-controlled voltage-source inverter. The lack of information (only two line-current sensors) requires an accurate and reliable reconstitution of the main quantities not sensed (flux, speed, torque). The results obtained show the excellent quality of the estimated speed, whatever the operating condition and despite the perturbations applied to the system. This study finally leads to the construction of a prototype. Cet article décrit l'étude et la mise en oeuvre d'un variateur de vitesse pour machine asynchrone sans capteur mécanique et alimentée par un onduleur de tension cotrôlé en courant. Le manque d'information (2 capteurs de courants de ligne uniquement) nécessite la reconstitution fiable et précise des grandeurs fondamentales non mesurées (flux, vitesse, couple). Les résultats obtenus montrent notamment l'excellente qualité de l'estimation de vitesse, quel que soit le point de fonctionnement et en dépit des perturbations auxquelles le système est soumis. Cette étude donne lieu à la réalisation d'un variateur prototype.

  8. Rachitisme patent révélé par la perte du contrôle des convulsions chez un garçon infirme moteur cérébral

    PubMed Central

    Awa, Hubert Désiré Mbassi; Chelo, David; Kinkela, Mina Njiki; Ndombo, Paul Olivier Koki

    2013-01-01

    La perte du contrôle des crises chez un patient compliant au traitement est toujours source de préoccupations diagnostiques, thérapeutiques et pronostiques. Nous rapportons un cas de rachitisme chez un patient de 4 ans, infirme moteur cérébral et épileptique sous traitement par phénobarbital depuis 2 ans; rachitisme découvert à la faveur d'une perte du contrôle épileptique. Le patient était admis pour des convulsions répétées en contexte afébrile. L'observance thérapeutique était bonne, et aucune convulsion n'avait été observée pendant les 12 mois précédents. Il ne recevait pas de vitamine D. Le rachitisme était suspecté cliniquement, et confirmé par les trouvailles radiologiques et biologiques. Le contrôle des crises était retrouvé dès le 3ème jour d'hospitalisation après apports de calcium intraveineux et de vitamine D. Les convulsions étaient imputées à une hypocalcémie sur rachitisme. La prise prolongée de phénobarbital sans supplémentation en vitamine D, ainsi qu'une exposition solaire insuffisante étaient incriminées. Avant toute escalade thérapeutique, des convulsions hypocalcémiques et un rachitisme doivent toujours être exclus devant une perte du contrôle des crises chez tout patient épileptique à mobilité réduite. Par ailleurs, une supplémentation en vitamine D et une exposition suffisante au soleil devront être recommandées pour certains traitements antiépileptiques au long cours. PMID:23503922

  9. Étude de la répartition des courants de Foucault pulsés dans une configuration de contrôle non destructif

    NASA Astrophysics Data System (ADS)

    Bour, J.-C.; Zubiri, E.; Vasseur, P.; Billat, A.

    1996-01-01

    Adjusting an experimental device of control by eddy-currents in sinusoidal or pulse mode requires the optimization of a certain number of parameters. Generally, the implementation of the latter operations is long and delicate, since it is issued of many compromises. The simulation study presented in this paper can be considered as a qualitative help because it specifies the the behaviour of the different parameters implied in the adjustment of the experimental defect reserach. First, we prove the influence of the lift-off on the defect detention's sensitivity of the flat sensor we used. Next we give prominence to the fact, in practice, we cannot disregard the geometry of the sensor, as we could do in theory. This result will lead us to define a family of curves showing the evolution of the depth of penetration as a function of the pulse's duration for different coil radii. We also determine the maximal sensor's sensitivity area, with the aim of locating the defect detected in the plate with precision. Finally, we prove the dependency between the true value of the depth of penetration and the thickness of the considered metallic plate. This very important result should equally be taken under consideration in the case of a real control. La mise au point d'un dispositif expérimental de contrôle par courants de Foucault, en mode sinusoïdal ou impulsionnel, nécessite l'optimisation d'un certain nombre de paramètres. Cette optimisation est généralement longue et délicate à exécuter en pratique puisqu'elle résulte de plusieurs compromis. L'étude en simulation présentée ici peut être considéré comme une aide plutôt qualitative, puisqu'elle précise le comportement des différents paramètres impliqués dans la mise en point de la recherche expérimentale de défauts. Nous montrons dans un premier temps l'influence de la distance capteur-cible sur la sensibilité du capteur à détecter un défaut. Nous mettons ensuite en évidence le fait de la g

  10. Transport adiabatique et phases de Berry : application au contrôle quantique cohérent passif

    NASA Astrophysics Data System (ADS)

    Viennot, D.

    2004-11-01

    L'étude de l'interaction d'atomes ou de molécules avec des champs électromagnétiques intenses, nécéssite le développement de nouveaux outils de modélisation rendant compte de la dynamique quantique de ces systèmes. Une approche purement perturbative étant impossible en champs forts, on s'est tourné vers une approche “adiabatique”. Afin de traiter correctement le cas des croisements de valeurs propres, on a généralisé les formules de transport adiabatique en faisant intervenir une généralisation de la phase de Berry non-abélienne.

  11. Evaluation de l’état vaccinal contre l’hépatite B et portage de l’Ag HBs chez le personnel médical et paramédical de l’Hôpital Central de Yaoundé, Cameroun

    PubMed Central

    Noah, Dominique Noah; Ngaba, Guy Pascal; Bagnaka, Servais Fiacre Eloumou; Assi, Constant; Ngantchet, Emmanuel; Njoya, Oudou

    2013-01-01

    Introduction L’hépatite virale B est une affection à haut risque pour le personnel de santé. Au Cameroun, la vaccination contre le virus de l’hépatite B n'est pas obligatoire pour le personnel de santé. Le but de l’étude était d'évaluer l’état vaccinal contre l’hépatite virale B et la prévalence de l’Antigène HBs au sein du personnel médical et paramédical de l’Hôpital Central de Yaoundé. Méthodes Il s'agissait d'une étude prospective, transversale menée à l’Hôpital Central de Yaoundé du 1er juillet au 31 octobre 2011. Toute personne membre du corps médical et paramédical ayant signée la fiche de consentement éclairé était incluse dans l’étude. Ceux ayant refusé de signer la fiche de consentement éclairé ou dont la fiche d'enquête n'avait pas été complètement remplie étaient exclus de l’étude. Une recherche systématique de l’antigène HBs était effectuée chez chaque personne incluse dans l’étude. Résultats Au total 282 personnes ont participé à l’étude sur 760, soit un taux de participation de 37,1%. Les personnes ne connaissant pas leur statut sérologique vis-à-vis du virus de l’hépatite B était au nombre de 221 (85%). Deux cent vingt-cinq (86,5%) personnes n'étaient pas vaccinées contre l’hépatite B. Les personnes ayant reçu moins de 3 doses du vaccin contre l’hépatite virale B étaient au nombre de 23 (8,8%). Douze personnes (4,6%) déclaraient avoir reçu les 3 doses du vaccin contre l’hépatite virale B. La prévalence de l’antigène HBs était de 6,6% (n = 12). Conclusion Cette étude montre que la prévalence de l’hépatite virale B reste élevée chez le personnel de l’Hôpital Central de Yaoundé (6,6%). Il ya un besoin de sensibilisation du personnel médical aux risques liés à l’exercice de leur profession. PMID:24778748

  12. Mise à jour sur la vaccination contre l’herpès zoster

    PubMed Central

    Shapiro, Marla; Kvern, Brent; Watson, Peter; Guenther, Lyn; McElhaney, Janet; McGeer, Allison

    2011-01-01

    Résumé Objectif Répondre aux questions fréquentes concernant l’utilisation du nouveau vaccin contre l’herpès zoster (HZ). Sources de l’information Les résultats publiés d’études cliniques et d’autres études, les recommandations du Comité consultatif national de l’immunisation du Canada et de l’Advisory Committee on Immunization Practices des États-Unis; des données ont aussi été obtenues dans la monographie du produit approuvée par Santé Canada sur le vaccin. Principal message L’herpès zoster est causé par la réactivation du virus varicelle-zoster; l’algie post-zostérienne (APZ) est sa complication la plus fréquente et la plus grave. L’incidence de l’APZ après un zona est directement reliée à l’âge, notamment 50 % des personnes affectées de plus de 60 ans qui ont des douleurs persistantes non soulagées. Le vaccin à base de virus vivant contre le HZ réduit l’incidence du zona d’environ 50 % et de 2 tiers l’apparition des APZ. De plus, les symptômes sont atténués et de plus courte durée chez les personnes vaccinées. Le vaccin est contre-indiqué chez de nombreux patients immunodéprimés et pourrait ne pas être efficace chez les patients qui prennent des médicaments antiviraux qui agissent contre le virus HZ. Les médecins devraient être au courant des différentes recommandations touchant ces groupes. Conclusion Le vaccin contre le HZ est une mesure de prévention sécuritaire et efficace pour réduire le fardeau global et la gravité du zona chez les adultes plus âgés. Le vaccin semble rentable lorsqu’il est administré à des adultes de 60 ans et plus.

  13. Un essai contrôlé randomisé: effet du port de chaussures à talons hauts sur le squelette appendiculaire inferieur

    PubMed Central

    Koussihouèdé, Fifamè Eudia Nadège; Falola, Jean-Marie; Fousseni, El-Mansour Barres

    2015-01-01

    Introduction Véritable attribut de la féminité, le port de chaussures à talons est devenu une exigence professionnelle dans certaines structures des pays en développement comme le Bénin. L'objectif de ce travail est de déterminer les effets spécifiques du port de chaussures à talons hauts sur le squelette appendiculaire inférieur. Méthodes Des examens radiographiques de face et de profil de la cheville et du genou ont été effectués sur 122 femmes volontaires, âgées en moyenne de 25,09 ± 1,34 ans et ayant les genu varum qui ont participé à cette étude. Résultats Les résultats ont indiqué une augmentation significative de l’écart inter malléolaire, de l’écart inter condylien, de l'angle antérieur du pied et de l'angle fémoro-patellaire. Une diminution significative de l'angle postérieur du pied a été constatée. Conclusion Le port de chaussures à talons hauts est l'une des causes de la gonarthrose, des troubles des articulations de la cheville et du pied. PMID:26113922

  14. La prévention des infections par le virus respiratoire syncytial

    PubMed Central

    Robinson, JL

    2011-01-01

    RÉSUMÉ L’infection par le virus respiratoire syncytial (VRS) est la principale cause d’infections des voies respiratoires inférieures chez les jeunes enfants. Le palivizumab, un anticorps monoclonal anti-VRS, réduit le taux d’hospitalisation des enfants à haut risque mais est très coûteux. Le présent document de principes remplace les trois précédents documents de principes de la Société canadienne de pédiatrie sur le sujet et est mis à jour principalement pour traiter des récentes modifications aux lignes directrices de l’American Academy of Pediatrics dans le contexte canadien. Il contient une analyse des publications ainsi que des recommandations au sujet de l’utilisation du palivizumab chez les enfants à haut risque

  15. Contrôle non destructif par courants de Foucault : expérience et modélisation pour la conception et l'optimisation de capteurs

    NASA Astrophysics Data System (ADS)

    Bonnin, O.; Cahouet, J.; Giordano, P.

    1993-03-01

    more accurate comparison, for example on the crack depth, is difficult because of the uncertainty on the physical properties of the materials. Dans le cadre d'un projet industiel de conception et d'optimisation de capteurs pour la recherche de fissures par courants de Foucault sur les plate-formes de forage, on présente les études menées pour la modélisation du système. La simulation des phénomènes implique à priori une modélisation tridimensionnelle, certes précise, mais difficile et coûteuse. On cherche à en limiter le coût en combinant une modélisation bidimensionnelle en l'absence de défaut, et une modélisation tridimensionnelle locale en présence d'une fissure. Après avoir présenté le projet et l'étude expérimentale qui en découle, on décrit les techniques de modélisation qui ont été employées.

  16. Contrôle du marché informel à l’heure de la mondialisation des échanges. Le cas des antirétroviraux au Chili

    PubMed Central

    Brousselle, Astrid; Morales, Cristián

    2013-01-01

    Résumé Les nouveaux médicaments pour le VIH/sida ont créé des besoins d’accessibilité aux traitements que les gouvernements n’ont pas toujours réussi à couvrir. Il en résulte l’émergence d’un marché informel des ARV. Par l’analyse de la situation au Chili, nous traitons des différents créneaux d’approvisionnement, des conséquences de l’existence d’un tel marché, ainsi que des moyens envisageables pour réduire les effets indésirables. Les aspects tant microéconomiques que macroéconomiques concernant le marché et l’accessibilité aux médicaments sont abordés. PMID:23997580

  17. Infection par le virus de l’hépatite E durant la grossesse

    PubMed Central

    Chaudhry, Shahnaz A.; Verma, Natasha; Koren, Gideon

    2015-01-01

    Résumé Question Plusieurs de mes patientes sont originaires de l’Asie du Sud-Est où le virus de l’hépatite E est assez commun. Quelles précautions puis-je leur suggérer de prendre avant de voyager dans cette région et quels sont les risques d’une infection par le VHE durant la grossesse? Réponse L’hépatite E est un pathogène présent dans l’eau qui se transmet par voie oro-fécale. Afin de réduire le risque de contracter le VHE lors de voyages dans des régions endémiques, il est important de maintenir des pratiques d’hygiène telles que se laver les mains avec de l’eau potable, particulièrement avant de manipuler de la nourriture, éviter de boire de l’eau ou d’utiliser des glaçons de pureté inconnue et ne pas manger de fruits ou de légumes non pelés. Actuellement, il n’existe aucun vaccin disponible au Canada pour le VHE. Une infection à l’hépatite E durant la grossesse, surtout durant le troisième trimestre, se caractérise par une infection plus sévère qui se transforme parfois en hépatite fulminante, augmentant ainsi les risques de mortalité et de morbidité maternelles et fœtales.

  18. La prévention de l’infection par le virus respiratoire syncytial

    PubMed Central

    Samson, L

    2009-01-01

    L’infection par le virus respiratoire syncytial (VRS) est la principale cause d’infection des voies respiratoires inférieures chez les jeunes enfants et pour cette raison, bon nombre des prématurés et des enfants présentant d’autres facteurs de risque doivent être hospitalisés chaque année au Canada. Le palivizumab, un anticorps monoclonal anti-VRS, peut réduire le taux d’hospitalisation et la gravité de la maladie d’un petit groupe de prématurés ou de nourrissons à haut risque pendant leur première saison de VRS. Le présent document de principes contient une analyse des publications ainsi que des recommandations à l’intention des médecins canadiens au sujet de son utilisation chez les prématurés et les autres nourrissons à risque.

  19. L’évaluation et le traitement du nourrisson exposé au virus d’immunodéficience humaine de type 1

    PubMed Central

    2004-01-01

    RÉSUMÉ Dans les pays industrialisés, des soins et un traitement sont offerts aux femmes enceintes et aux nourrissons, afin de faire chuter à 2 % ou moins le taux d’infection périnatale au virus d’immunodéficience humaine de type 1 (VIH-1). Le pédiatre joue un rôle de premier plan dans la prévention de la transmission du VIH-1 de la mère à l’enfant par le dépistage des nourrissons exposés au VIH dont l’infection au VIH de la mère n’a pas été diagnostiquée avant l’accouchement. Il prescrit une prophylaxie antirétrovirale à ces nourrissons, afin de réduire le risque d’acquisition de l’infection au VIH-1 et d’en éviter le plus possible la transmission par le lait maternel. De plus, le pédiatre peut soigner les nourrissons exposés au VIH-1 en les surveillant pour obtenir un dépistage précoce de l’infection au VIH-1 et évaluer les toxicités à court et à long terme de l’exposition aux antirétroviraux, assurer une chimioprophylaxie de la pneumonie à Pneumocystis et soutenir les familles qui vivent avec une infection au VIH-1, grâce à des conseils thérapeutiques aux parents ou aux soignants.

  20. Incidence du carcinome hépatocellulaire lors de l'infection chronique par le virus de l'hépatite B

    PubMed Central

    Ntagirabiri, Rénovat; Munezero, Bélyse; Kaze, Hippolyte; Ndirahisha, Eugène; Manirakiza, Sébastien

    2015-01-01

    Introduction Le virus de l'hépatite B (VHB) est incriminé comme cause de cancer primitif du foie. Le stade de fibrose et d'autres facteurs environnementaux et génétiques seraient intriqués. Le but de notre travail était de déterminer l'incidence du carcinome hépatocellulaire (CHC) lors d'une infection chronique par le VHB et estimer le risque relatif (RR) de CHC lié au stade de la fibrose hépatique. Méthodes Étude prospective de suivi d'une cohorte de patients porteurs chroniques du VHB sur une période de 5 ans (2009 à 2014). Etaient inclus les patients consécutifs qui ont subi un dosage de la charge virale B, une évaluation de la fibrose hépatique et un suivi régulier de tous les 6 à 12 mois par une échographie hépatique. Résultats Au total 194 patients ont été retenus. L’âge moyen était de 39,1 ans. Parmi eux 112 étaient des hommes. L'incidence cumulée de CHC a été de 8,8% dans la population d’étude soit une incidence annuelle de 1,8%. Selon le stade de fibrose, 31 patients avaient une fibrose sévère ou une cirrhose (score Fibrotest >0,73). Parmi eux, l'incidence cumulée de CHC était de 35,5% soit une incidence annuelle estimée à 7,10%. Parmi 163 patients ayant une fibrose mineure, l'incidence cumulée de CHC était de 3,7% soit une incidence annuelle de 0,7%. Le RR lié à la cirrhose était de 9,7; IC 95%: (3,8-24,1%). Conclusion Le VHB expose au CHC jusqu’à 10 fois. La fibrose sévère et la cirrhose constituent des facteurs prédictifs de CHC chez le porteur chronique du VHB. Evaluer systématiquement la fibrose pour traiter précocement les malades pourra prévenir l’évolution vers la cirrhose et par là réduire la survenue du CHC. PMID:26113910

  1. Choriorétinite extensive bilatérale révélant une infection par le virus de l'immunodéficience humaine (VIH)

    PubMed Central

    El Yamouni, Oubaida; Tzili, Nazih; El Hassan, Abdallah; Slassi, Nadia; El Khaoua, Mahfoud; Jebbar, Zakaria; Berraho, Amina

    2014-01-01

    Au cours de l'infection par le virus de l'immunodéficience humaine(VIH), Les atteintes oculaires sont polymorphes, pouvant compromettre le pronostic fonctionnel. Nous rapportons l'observation d'un patient présentant une choriorétinite infectieuse sévère révélant une infection par le VIH. Patient âgé de 35 ans avec antécédent de tuberculose pulmonaire en 2007, consulte pour BAV bilatérale progressive depuis 6 mois. Une acuité visuelle à compte les doigts au niveau de l'oeil droit et à mouvement des doigts au niveau de l'oeil gauche, avec présence de foyers choriorétiniens diffus visualisés au fond d'oeil et à l'angiographie. Les sérologies VIH, toxoplasmose et CMV sont positives. Le patient a été mis sous traitement anti-toxoplasmose (Sulfadiazine et pyriméthamine) et anti-CMV (Ganciclovir per os). L’évolution sous traitement a été marquée par une régression de la hyalite avec la persistance des foyers choriorétiniens évolutifs et une acuité visuelle réduite à perception lumineuse. PMID:25709723

  2. Allier théorie et pratique dans la lutte contre la pandémie du Sida

    PubMed Central

    Zerbo, Roger

    2014-01-01

    Le premier cas d'infection par le VIH a été notifié en 1986 au Burkina Faso. L'ignorance qui entourait cette infection et l'absence de traitement curatif a amplifié ses conséquences sociales et économiques. La mise en œuvre des interventions communautaire est un enjeu majeur actuel qui recommande la compréhension des logiques sociales endogènes qui influencent les comportements individuels et collectifs. C'est en cela que l'implication des sciences sociales dans la lutte contre les maladies, en particulier le Sida constitue un enjeu, en termes de définition et d'identification de leur contribution. Dans notre propos, nous pouvons mettre en évidence trois niveaux de contribution des sciences sociales, notamment la sociologie, l'anthropologie, la psychologie et dans une certaine mesure le droit et l’économie, à la prévention du Sida et la prise en charge des personnes infectées par le VIH. Il faut noter que ces disciplines contribuent à la lutte contre le VIH d'une part, par des réflexions et des éléments d'analyses constructives, et d'autre part, l'aptitude des porteurs de ces disciplines est parfois sollicitée pour l'efficacité de la mise en œuvre des actions et l'organisation des systèmes de soins. PMID:25722761

  3. "L'unilinguisme" francais contre le changement sociolinguistique (French "Unilingualism" versus Sociolinguistic Change).

    ERIC Educational Resources Information Center

    Boyer, Henri

    2001-01-01

    This article describes the French unilingual, also seen as a sociolinguistic ideology, in its varieties, especially since the French Revolution: an ideology based on few representations that are both inner and outer linguistic. The article also discusses the attitude of the unilingual in the collective epilinguistic field of experiment. One…

  4. Viruses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Lytic bacteriophages, viruses which infect and lyse bacterial cells, can provide a natural method to reduce bacterial pathogens on produce commodities. The use of multi-phage cocktails is most likely to be effective against bacterial pathogens on produce commodities, and minimize the development of...

  5. Les facteurs prédictifs de morbimortalité chez les patients sous ballon de contre pulsion intra-aortique en chirurgie cardiaque

    PubMed Central

    Elahmadi, Brahim; Motiaa, Youssef; Hatim, Abdedaim Elghadbane; Atmani, Noureddine; Moutakillah, Younes; Wahid, Fouad Amal; Elbekkali, Youssef; Houssa, Mahdi Ait; Razine, Rachid; Boulahya, Abdelatif; Drissi, Mohammed

    2015-01-01

    Le ballon de contre pulsion intra-aortique (BCPIA) est fréquemment utilisé en chirurgie cardiaque, comme moyen d'assistance circulatoire en cas de bas débit cardiaque. Il est d'intérêt clinique de déterminer les facteurs pronostiques chez les patients porteurs d'un BCPIA en chirurgie cardiaque, et qui restent un sujet rarement élucidé dans la littérature. L'objectif de notre travail est de déterminer les facteurs prédictifs de morbi-mortalité chez les patients sous ballon de contre pulsion intraortique en périopératoire d'une chirurgie cardiaque. Il s'agit d'une étude rétrospective portant sur l'ensemble des patients opérés en chirurgie cardiaque sous circulation extracorporelle, et ayant bénéficiés de la mise en place d'un ballon de contre pulsion intra-aortique en périopératoire, au service de chirurgie cardiovasculaire de l'Hôpital Militaire Mohamed V de Rabat, entre le mois de janvier 2005 et le mois d'aout 20014. Soixante dix patients ont été inclus dans notre étude. En analyse univariée l'âge, la dyspnée de stade III et IV, l'insuffisance cardiaque, la présence d'un infarctus du myocarde, d'une coronaropathie mono et bitronculaire, les anomalies du doppler de trons supra-aortique et du membre inférieur, le caractère urgent de la chirurgie, la durée de la circulation extracorporelle, l'instabilité hémodynamique postopératoire, le saignement et l'insuffisance rénale postopératoire étaient statistiquement associés à une mortalité postopératoire élevée. La dyskinésie préopératoire et la sortie de circulation extracorporelle sous drogues étaient associées à une morbidité globale élevée. En analyse multi variée, seule l'âge, constituait un facteur de risque indépendant de mortalité dans notre série avec un Odds Ratio (OR): 1,89 ; un Intervalle de Confiance (IC) 95% de (1,52-4,97) et un p =0,045. Au terme de notre étude, le taux de mortalité était de 48,57% et de morbidité globale était de 87,1%. Il

  6. La tuberculose pulmonaire et le tabac: à propos de 100 cas

    PubMed Central

    Janah, Hicham; Souhi, Hicham; Kouissmi, Hatim; Marc, Karima; Zahraoui, Rachida; Benamor, Jouda; Soualhi, Mona; Bourkadi, Jamal Eddine

    2014-01-01

    Le tabagisme et la tuberculose sont deux enjeux majeurs de santé publique au niveau mondial, en particulier dans les pays émergents. Pour déterminer les particularités cliniques, radiologiques, bactériologiques et thérapeutiques de la tuberculose pulmonaire chez les sujets tabagiques nous avons mené une étude prospective au service de phtisiologie de l'hôpital Moulay Youssef sur une période de 10 mois, portant sur 100 nouveaux cas de tuberculose pulmonaire, répartis en 2 groupes, 50 patients tabagiques: Groupe A et 50 patients non tabagiques: Groupe B. Tous nos patients étaient de sexe masculin, l’âge moyen était de 41 ans ± 12 chez le groupe A et de 36 ans ± 16 chez le groupe B. Le délai de consultation était plus long chez les tabagiques, la médiane était de 60j (30; 98) contre 40j (30; 60), la symptomatologie clinique était variable chez les deux groupes, dominée par les expectorations chez les tabagiques 96% contre 60%. Les lésions radiologiques étaient similaires chez les deux groupes ainsi que la charge bacillaire. Tous les patients ont été mis sous traitement antituberculeux. Après un mois du traitement, la Bacilloscopie était négative chez 50% du groupe A contre 66% chez le groupe B. la régression des lésions radiologiques était similaire chez les deux groupes. Le retard diagnostique et le retard de négativation des frottis sont les principales particularités de la tuberculose pulmonaire du sujet tabagique. Le sevrage tabagique doit faire partie intégrante de la prise en charge des patients atteints de tuberculose. PMID:25821545

  7. L'atteinte osseuse dans le sarcome de Kaposi classique et agressif: à propos d'un cas

    PubMed Central

    Sbiyaa, Mouhcine; El Alaoui, Adil; El Bardai, Mohammed; Mezzani, Amine; Lahrach, Kamal; Marzouki, Amine; Boutayeb, Fawzi

    2016-01-01

    Le sarcome de Kaposi classique est une tumeur rare multifocale d'origine des cellules endothéliales vasculaires à caractère évolutif progressif et peu maligne. L'atteinte viscérale dans le sarcome de kaposi est parfois observée chez les patients VIH positif par contre la dissémination tumorale dans les ganglions lymphatiques viscérales dans le SK classique reste très rare. On rapporte un cas rare de sarcome de kaposi classique agressif de la main avec une évolution rapide et destructive. PMID:27347285

  8. Contrôler la douleur et réduire l’usage abusif d’opioïdes

    PubMed Central

    Kotalik, Jaro

    2012-01-01

    Résumé Objectif Aider les médecins de famille à faire un juste équilibre sur le plan de l’éthique dans leurs pratiques de prescription d’opioïdes. Source des données Une recension des articles en anglais publiés entre 1985 et 2011 a été effectuée dans MEDLINE. La majorité des données probantes étaient de niveau III. Message principal Il est essentiel de suivre les guides de pratique clinique quand on prescrit des opioïdes, sauf s’il est démontré qu’une autre option est justifiée. De plus, quand on réfléchit à la pertinence de prescrire des opioïdes et aux nombreuses implications sur le plan de l’éthique, il est utile de fonder sa décision sur l’application des principes éthiques de la bienfaisance, de la non-malfaisance, du respect de l’autonomie et de la justice. En outre, il est essentiel de se tenir au fait des changements dans les lois et la règlementation, ainsi qu’à propos des registres électroniques provinciaux des ordonnances d’opioïdes. Conclusion Les médecins doivent s’assurer que la douleur de leurs patients est bien évaluée et prise en charge. Le contrôle optimal de la douleur peut exiger la prescription d’opioïdes. Cependant, l’obligation de soulager la douleur doit être exercée en juste équilibre avec l’acquittement de la responsabilité tout aussi importante de ne pas exposer les patients au risque de dépendance et de ne pas créer de possibilités de détournement de drogues, de trafic et de dépendance chez d’autres personnes. Les principes éthiques fondamentaux offrent un cadre de réflexion qui peut aider les médecins à prendre des décisions appropriées sur le plan de l’éthique au sujet de la prescription d’opioïdes.

  9. Efficacité de la prévention de la transmission mère-enfant du Virus de l'Immunodéficience Humaine par le protocole 2010 de l'Organisation Mondiale de la Santé au Centre Médical Saint Camille de Ouagadougou (Burkina Faso)

    PubMed Central

    OuédraogoYugbaré, Solange Odile; Zagré, Nikaise; Koueta, Fla; Dao, Lassina; Kam, Ludovic; Ouattara, Diarra Yé; Simporé, Jacques

    2015-01-01

    L’épidémie du Virus de l'Immunodéficience Humaine en milieu pédiatrique est surtout le résultat de la transmission mère-enfant. Notre étude a pour objectif de décrire l'efficacité de la prévention de la transmission mère-enfant du Virus de l'Immunodéficience Humaine par le protocole OMS 2010 (Option A et trithérapie) au centre médical saint Camille de Ouagadougou. Nous avons mené une étude d'une cohorte d'enfants suivis dans le cadre de la prévention de la transmission mère-enfant du Virus de l'Immunodéficience Humaine au centre médical saint Camille de Ouagadougou sur une période de 2 ans allant du 1er Janvier 2012 au 31 Décembre 2013. Nous avons obtenu l'accord de 4900 femmes enceintes pour le dépistage de l'infection du Virus de l'Immunodéficience Humaine et 238 gestantes ont été diagnostiquées séropositives soit 4,86% de séroprévalence. Les femmes étaient surtout infectées par le Virus de l'Immunodéficience Humaine avec de type I (95,38%)). La majorité était sous trithérapie (74,3%) et (25,7%) sous prophylaxie (option A). Les nouveau-nés (92,5%) ont reçu un traitement antirétroviral à base de névirapine dans les 72 heures après la naissance. L'allaitement sécurisé a été appliquée dans 78% des cas. Le taux global de transmission mère-enfant du VIH était de 3,6% avec 3% de transmission chez les enfants nés de mères sous trithérapie antirétrovirale et 6,3% dans les cas de prophylaxie antirétrovirale. Le facteur de risque de transmission a été le long délai du début d'administration des antirétroviraux chez le nouveau-né. La mortalité infantile à un an était de 3,5%. Cette étude a révélé l'efficacité de l'Option A et conforté celle de la trithérapie, le passage à l'Option B+ serait donc plus bénéfique. PMID:26966499

  10. Revue systématique sur la contribution des femmes distributeurs communautaires dans la lutte contre l'onchocercose en Afrique sub-saharienne

    PubMed Central

    Vouking, Marius Zambou; Tadenfok, Carine Nouboudem; Evina, Christine Danielle; Nsangou, Moustapha; Bonono, Cécile-Renée; Yondo, David

    2014-01-01

    Le Programme Africain de lutte contre l'Onchocercose (APOC) fut lancé en 1995, comme complément au brillant programme de lutte contre l'onchocercose en Afrique de l'Ouest. En 2011, plus de 80 millions de personnes ont bénéficié de cette intervention grâce à la contribution de 268 718 Distributeurs Communautaires (DC). Ses résultats significatifs occultent lele des femmes DC dans cette lutte cette maladie. L'objectif de cette analyse est de déterminer la contribution des femmes DC dans le traitement de l'onchocercose sous directive communautaire en Afrique sub-saharienne, et d’évaluer leur acceptation dans ledit programme. Comme stratégie de recherche, nous avons identifié toutes les études pertinentes de Janvier 1995 à Décembre 2012. Des recherches ont été effectuées dans les bases de données suivantes: Medline, Embase (Excerpta Medica Database), CINAHL (Cumulative Index to Nursing and Allied Health Literature), LILAS (Latin American and Caribbean Literature on Health Sciences). Nous avons également consulté les sites d'APOC et de l'OMS AFRO. Deux auteurs ont indépendamment évalué la pertinence des articles potentiels à l'aide des critères d'inclusion et d'exclusion bien définis. Six (6) des 25 études ont rempli les critères d'inclusion. Une étude a montré que 81% des populations où il y avait des femmes DC ont reçu l'Ivermectine par rapport à 78% des villages où n'exerçaient pas de femmes DC. Une autre étude a montré qu'il y a eu une prise de conscience croissante dans les IDC en faveur de l'acceptation de la participation des femmes à la distribution communautaire de l'Ivermectine. De plus, 70% des membres de la communauté interrogés dans certaines zones endémiques, ont déclaré que les femmes étaient plus engagées, persuasives et plus patientes que les hommes dans la distribution de l'Ivermectine. Au terme de cette étude, les évaluations qui ont été effectuées donnent à penser que les femmes peuvent jouer

  11. Étude comparative de l’innocuité de deux vaccins commerciaux contre la babésiose canine provoquée par Babesia canis

    PubMed Central

    Freyburger, L.; Lemaitre, L.; Médaille, C.; Oberli, F.; Fanchon, L.; Bergamo, P.

    2011-01-01

    L’innocuité de deux vaccins commercialisés en France contre la babésiose canine – Nobivac Piro® (NP) et Pirodog® (P) – a été étudiée. Leur impact local, général et biochimique a été comparé, en conditions expérimentales maîtrisées, sur un groupe témoin (T) et deux groupes vaccinés deux fois à 21 jours d’intervalle. Tous les chiens ont présenté une réaction locale modérée. Cependant, le groupe NP a présenté une réaction locale significativement plus intense que le groupe P. Ceci est objectivé par les paramètres cliniques et biologiques. Aucune différence statistiquement significative n’est mise en évidence entre les évolutions des groupes P et T. PMID:22091461

  12. Protéger les nourrissons contre la coqueluche

    PubMed Central

    Gilley, Meghan; Goldman, Ran D.

    2014-01-01

    Résumé Question Compte tenu du taux à la hausse de la coqueluche chez les enfants, plusieurs familles m’ont demandé quels moyens prendre pour protéger leurs tout-petits de cette infection. Quelles devraient être mes recommandations à ces familles? Réponse La coqueluche est une maladie évitable qui est endémique dans le monde entier. Chez les adultes, la coqueluche cause une maladie bénigne semblable à un rhume, suivie d’une toux persistante. Chez les nourrissons, elle peut causer de l’apnée, des convulsions, une encéphalopathie, une bronchopneumonie et la mort. Les décès dus à la coqueluche se produisent dans 86 % des cas chez des nourrissons de moins de 4 mois. La stratégie du cocooning, c’est-à-dire la vaccination des adultes en étroit contact avec des nourrissons, est recommandée par de nombreuses agences mondiales et nationales, mais elle ne prévient probablement que 20 % des cas de coqueluche chez les nourrissons. La vaccination durant la grossesse est plus efficace, mais elle n’est pas encore approuvée au Canada. Il n’a pas été démontré que la vaccination à la naissance soit uniformément efficace et elle n’est donc pas recommandée à l’heure actuelle.

  13. Les fluctuations supraconductrices dans le compose praseodyme-cerium-oxyde de cuivre

    NASA Astrophysics Data System (ADS)

    Renaud, Jacques

    Ce travail etudie les fluctuations supraconductrices dans le compose supraconducteur a haute temperature critique dope aux electrons Pr2-xCe xCuO4+delta. La technique utilisee pour sonder ces fluctuations est le transport electrique DC dans le plan ab. Il s'agit, a notre connaissance, de la premiere etude de ce type dans la classe generale des supraconducteurs a haute temperature critique dopes aux electrons et, plus particulierement, dans Pr2-xCe xCuO4+delta. De plus, l'etude est effectuee pour trois regimes de dopage, soit sous-dope x = 0.135, dopage optimal x = 0.15 et surdope x = 0.17. Les echantillons etudies sont des couches minces d'epaisseur plus grande que 100 nm crues par ablation laser. Les mesures electriques DC effectuees dans ce travail sont la resistance en reponse lineaire et les courbes IV en reponse non lineaire en fonction de la temperature. La mise en oeuvre experimentale de ces mesures a necessite une grande attention au filtrage et aux effets de chauffage a haut courant. Nous montrons que, sans cette attention, les donnees experimentales sont toujours erronees dans le regime pertinent pour nos echantillons. Les resultats pour le dopage optimal x = 0.15 sont expliques de facon tres convaincante dans le cadre de fluctuations purement 2D. D'abord, le regime des fluctuations gaussiennes est tres bien decrit par le modele d'Aslamazov-Larkin en deux dimensions. Ensuite, le regime de fluctuations critiques, se trouvant a plus basse temperature que le regime gaussien, est tres bien decrit par la physique 2D de Kosterlitz-Thouless. Dans cette analyse, les deux regimes ont des temperatures critiques coherentes entre elles, ce qui semble confirmer ce scenario 2D. Une analyse des donnees dans le cadre de fluctuations 3D est exploree mais donne des conclusions incoherentes. Les resultats pour les autres dopages sont qualitativement equivalents avec le dopage optimal et permettent donc une explication purement 2D. Par contre, contrairement au dopage optimal

  14. La chirurgie coronaire sous circulation extra-corporelle chez le patient diabétique

    PubMed Central

    Moutakiallah, Younes; Benzaghmout, Khadija; Aithoussa, Mahdi; Atmani, Nourreddine; Amahzoune, Brahim; Hatim, Abdedaim; Drissi, Mohamed; Benyass, Aatif; ElBekkali, Youssef; Boulahya, Abdelatif

    2014-01-01

    Nous rapportons les résultats de la chirurgie coronaire chez une population de coronariens diabétiques opérés sous circulation extra-corporelle dans le service de chirurgie cardiaque de l'hôpital militaire d'instruction Mohammed V de Rabat. C'est une étude rétrospective menée entre Janvier 2008 et Février 2012 (4 ans), portant sur 103 patients diabétiques consécutifs opérés pour pontage coronaire. L’âge moyen des patients était de 61±8,7ans (37-82ans) avec un sexe ratio (H/F) de 3,9. Tous les patients diabétiques de type 2 et sous traitement anti-diabétique ont été inclus dans cette étude. La sténose du tronc commun gauche était présente chez 26,2% des patients et 53,4% étaient tritronculaires. Quatre-vingt patients (78,6%) étaient insulino-nécessitant, l'Euro-score moyen était de 1,63±1% et le nombre moyen de pontage de 2,3±0,7. Les durées moyennes de la circulation extra-corporelle et du clampage aortique étaient respectivement de 134,4 ± 42 min et 76 ± 28 min. La mortalité hospitalière était de 2 décès (1,9%), les durées moyennes de ventilation artificielle, du séjour en réanimation et du séjour postopératoire étaient respectivement de 7h (5-16h), 48h (42-52h) et 15,6 ± 8,6 jours. Les complications postopératoires étaient l'infarctus du myocarde, l'infection de paroi, la médiastinite et le bas débit cardiaque chez respectivement 1,9%, 10,7%, 3,9% et 1,9% des patients. Il ressort de notre étude, que les facteurs prédictifs d'infection post opératoire étaient la durée de ventilation artificielle (p = 0,002), la durée de la circulation extra-corporelle (p < 0,001) en plus du tabac (p = 0,004) et de l'obésité (p = 0,005). Les patients ont été contactés par téléphone ou lors de la consultation régulière de contrôle. Le taux de suivi a atteint 92,1% et la survie à 2 ans était de 98,9% des patients contrôlés avec une mortalité tardive de 1% avec un décès suite à un accident vasculaire c

  15. Le Indeterminacy in Spanish.

    ERIC Educational Resources Information Center

    Foster, David William

    The standard treatment of object pronouns in Latin American Spanish assigns a direct-object function to "lo" and "la" and an indirect-object function to "le." This study challenges this descriptive attribution in light of the contradictory and refractory evidence in Spanish morphosyntax. It is suggested that more detailed research, especially…

  16. Le Figaro. Revised.

    ERIC Educational Resources Information Center

    Crawford, Linda

    These instructional materials are designed for students with some French reading skills and vocabulary in late beginning or early intermediate senior high school French. The objectives are to introduce students to a French newspaper, "Le Figaro," and develop reading skills for skimming, gathering specific information, and relying on cognates. The…

  17. Le mouvement du pôle

    NASA Astrophysics Data System (ADS)

    Bizouard, Christian

    2012-03-01

    Les variations de la rotation terrestre. En conditionnant à la fois notre vie quotidienne, notre perception du ciel, et bon nombre de phénomènes géophysiques comme la formation des cyclones, la rotation de la Terre se trouve au croisement de plusieurs disciplines. Si le phenomena se faisait uniformément, le sujet serait vite discuté, mais c'est parce que la rotation terrestre varie, même imperceptiblement pour nos sens, dans sa vitesse angulaire comme dans la direction de son axe, qu'elle suscite un grand intérêt. D'abord pour des raisons pratiques : non seulement les aléas de la rotation terrestre modi_ent à la longue les pointés astrométriques à un instant donné de la journée mais in_uencent aussi les mesures opérées par les techniques spatiales ; en consequence l'exploitation de ces mesures, par exemple pour déterminer les orbites des satellites impliqués ou pratiquer le positionnement au sol, nécessite une connaissance précise de ces variations. Plus fondamentalement, elles traduisent les propriétés globales de la Terre comme les processus physiques qui s'y déroulent, si bien qu'en analysant les causes des fluctuations observées, on dispose d'un moyen de mieux connaître notre globe. La découverte progressive des fluctuations de la rotation de la Terre a une longue histoire. Sous l'angle des techniques d'observation, trois époques se pro-celle du pointé astrométrique à l'oeil nu, à l'aide d'instruments en bois ou métalliques (quart de cercle muraux par exemple). À partir du XVIIe siècle débute l'astrométrie télescopique dont les pointés sont complétés par des datations de plus en plus précises grâce à l'invention d'horloges régulées par balancier. Cette deuxième époque se termine vers 1960, avec l'avènement des techniques spatiales : les pointés astrométriques sont délaissés au profit de la mesure ultra-précise de durées ou de fréquences de signaux électromagnétiques, grâce à l'invention des horloges

  18. Lele de l’omalizumab dans le traitement de l’asthme allergique grave

    PubMed Central

    Chapman, Kenneth R; Cartier, André; Hébert, Jacques; McIvor, R Andrew; Schellenberg, R Robert

    2006-01-01

    CONTEXTE : Un nouveau traitement anti-immunoglobuline E (anti-IgE) contre l’asthme, l’omalizumab, a été approuvé au Canada. OBJECTIF : Passer en revue les données fondamentales et cliniques sur l’omalizumab et examiner lele possible de ce médicament dans la prise en charge de l’asthme au Canada. MÉTHODOLOGIE : Une recherche documentaire a été effectuée dans MEDLINE afin de repérer les études menées de 1960 à 2006 sur l’omalizumab. La recherche a également porté sur les résumés de réunions scientifiques récentes dans le domaine des maladies respiratoires et des allergies; par ailleurs, toute donnée non publiée a été demandée au fabricant. Après avoir revu et résumé les données, un comité mixte constitué de spécialistes des maladies respiratoires et des allergies a rédigé un ensemble de recommandations relatives à l’utilisation de l’omalizumab. RÉSULTATS : L’omalizumab est un anticorps monoclonal humanisé qui se lie au domaine C epsilon 3 de la molécule d’IgE pour former des complexes immuns solubles qui sont éliminés par le système réticulo-endothélial. L’administration d’injections sous-cutanées espacées de deux ou de quatre semaines à la dose recommandée entraîne une diminution rapide des taux d’IgE circulantes libres. Lors de deux essais cliniques de phase III menés auprès de 1 405 adultes et adolescents atteints d’asthme modéré à grave qui recevaient des doses moyennes stables de corticostéroïdes en inhalation (CSI), l’omalizumab a diminué les taux d’exacerbation par rapport au placebo et a été associé à une amélioration des symptômes ainsi qu’à une épargne plus importante des corticostéroïdes. Dans un essai mené auprès de 419 patients atteints d’asthme grave non maîtrisé malgré l’utilisation de doses élevées de CSI et de la prise concomitante d’agonistes bêta-2 à action prolongée, les exacerbations graves étaient de 50 % moins fréquentes chez

  19. Le zona ophtalmique: une dermatose rare chez l'enfant

    PubMed Central

    Zakia, Douhi; Meziane, Marieme; Salim, Gallouj; Zahra, Mernissi Fatima

    2015-01-01

    Le zona est dû a une réactivation du virus varicelle-zona (VZV) qui reste quiescent dans les ganglions sensitifs dorsaux après la varicelle. Le zona de l'enfant est rare et particulièrement la forme ophtalmique, qui peut être responsable de complications oculaires graves nécessitant une prise en charge adéquate et précoce. Il est parfois associé à des douleurs post-zostériennes dont le traitement est difficile. L'aciclovir per os administré dans les 72 heures après l’éruption a prouvé son efficacité dans la prévention des complications oculaires. Nous en rapportant un nouveaux cas chez un garçon immunocompétent de 9 ans, sans notion de varicelle antérieure. PMID:26955408

  20. ECHO virus

    MedlinePlus

    ... page: //medlineplus.gov/ency/article/001340.htm ECHO virus To use the sharing features on this page, please enable JavaScript. Enteric cytopathic human orphan (ECHO) viruses are a group of viruses that lead to ...

  1. Lele de métrologie de SOLEIL

    NASA Astrophysics Data System (ADS)

    Idir, M.; Brochet, S.; Delmotte, A.; Lagarde, B.; Mercere, P.; Moreno, T.; Polack, F.; Thomasset, M.

    2006-12-01

    de microfocalisation, monochromateurs, diagnostics d'imagerie) font que les performances de ces instruments sont désormais limitées par les imperfections de fabrication des composants optiques. La métrologie des surfaces optiques est donc une nécessité impérieuse pour tous les acteurs du domaine, qui se doivent d'effectuer les contrôles appropriés. Cette pression s'exerce aussi sur les moyens utilisés pour effectuer ces mesures, car les incertitudes de mesure actuelles, notamment en ce qui concerne la régularité des surfaces, sont loin d'être négligeables vis à vis des tolérances demandées. Il est donc indispensable de faire évoluer les instruments de mesure et d'obtenir des gains significatifs de précision. Un travail particulier est en cours au laboratoire de Métrologie pour développer à côté des instruments commerciaux, des instruments prototypes sur des concepts originaux (mesures de profils de surface et mesures d'angle). Dans cet article, nous donnons des détails des choix techniques utilisés sur la ligne de METROLOGIE et TESTS et des performances attendues et nous décrirons le laboratoire de METROLOGIE en donnant des exemples d'optiques récemment testées.

  2. Technique de Blount dans le traitement des fractures supra condyliennes du coude chez l'enfant: à propos de 68 cas

    PubMed Central

    Chagou, Aniss; Rhanim, Abdelkarim; Zanati, Rachid; Kharmaz, Mohammed; Lamrani, Moulay Omar; Berrada, Mohammed Saleh; El Yaacoubi, Moradh; Ettaybi, Fouad

    2014-01-01

    La fracture de la palette humérale est la plus fréquente des fractures du coude de l'enfant. La méthode de BLOUNT, constitue une perspective thérapeutique longtemps connue. Elle consiste en une réduction sous contrôle scopique de la fracture et une contention en hyper flexion du coude. Notre série a porté sur l’étude de 68 cas de fractures supra condyliennes chez des enfants traités dans le service des urgences chirurgicales pédiatriques de l'hôpital d'enfant de Rabat entre janvier 2009 et janvier 2012. Nous comparons nos résultats avec les données de la littérature. PMID:25667714

  3. NEP facilities (LeRC)

    NASA Astrophysics Data System (ADS)

    Vetrone, Robert H.

    The topics are presented in viewgraph form and include the following: the Electric Propulsion Research Building (no. 16) the Electric Power Laboratory (BLDG. 301); the Tank 6 Vacuum Facility; and test facilities for electric propulsion and LeRC.

  4. Tectonique active du Nord-Est de Sulawesi(Indonésie) et contrôle structural de la caldeira de Tondano

    NASA Astrophysics Data System (ADS)

    Lécuyer, Frédéric; Bellier, Olivier; Gourgaud, Alain; Vincent, Pierre M.

    1997-10-01

    Field study and SPOT image analyses on the Tondano caldera region permit us to show a distributed active sinistral strike-slip fault zone which trends ENE- WSW This faulting accommodates the N-S movement of the Celebes Sea plate and represents a transfer fault zone between the Celebes sea subduetion end and the Moluccas sea subduetion zone. Furthermore, this study permits us to provide evidence for a tectonic control of the Tondano caldera collapse and evolution.

  5. Le bégaiement

    PubMed Central

    Perez, Hector R.; Stoeckle, James H.

    2016-01-01

    Résumé Objectif Fournir une mise à jour sur l’épidémiologie, l’hérédité, la physiopathologie, le diagnostic et le traitement du bégaiement développemental. Qualité des données Une recherche d’études récentes ou non portant sur l’épidémiologie, l’hérédité, la physiopathologie, le diagnostic et le traitement du bégaiement développemental a été effectuée dans les bases de données MEDLINE et Cochrane. La plupart des recommandations s’appuient sur des études de petite envergure, des données probantes de qualité limitée ou des consensus. Message principal Le bégaiement est un trouble d’élocution fréquent chez les personnes de tous âges, il altère la fluidité verbale normale et l’enchaînement du discours. Le bégaiement a été lié à des différences de l’anatomie, du fonctionnement et de la régulation dopaminergique du cerveau qui seraient de source génétique. Il importe de poser le diagnostic avec attention et de faire les recommandations qui conviennent chez les enfants, car de plus en plus, le consensus veut que l’intervention précoce par un traitement d’orthophonie soit cruciale chez les enfants bègues. Chez les adultes, le bégaiement est lié à une morbidité psychosociale substantielle, dont l’anxiété sociale et une piètre qualité de vie. Les traitements pharmacologiques ont soulevé l’intérêt depuis quelques années, mais les données cliniques sont limitées. Le traitement des enfants et des adultes repose sur l’orthophonie. Conclusion De plus en plus de recherches ont tenté de lever le voile sur la physiopathologie du bégaiement. La meilleure solution pour les enfants et les adultes bègues demeure la recommandation à un traitement d’orthophonie.

  6. Foodborne viruses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Testing for human pathogenic viruses in foods represents a formidable task requiring the extraction, concentration, and assay of a host of viruses from a wide range of food matrices. The enteric viruses, particularly genogroup I and II (GI and GII) noroviruses and hepatitis A virus, are the princip...

  7. Inventing Viruses.

    PubMed

    Summers, William C

    2014-11-01

    In the nineteenth century, "virus" commonly meant an agent (usually unknown) that caused disease in inoculation experiments. By the 1890s, however, some disease-causing agents were found to pass through filters that retained the common bacteria. Such an agent was called "filterable virus," the best known being the virus that caused tobacco mosaic disease. By the 1920s there were many examples of filterable viruses, but no clear understanding of their nature. However, by the 1930s, the term "filterable virus" was being abandoned in favor of simply "virus," meaning an agent other than bacteria. Visualization of viruses by the electron microscope in the late 1930s finally settled their particulate nature. This article describes the ever-changing concept of "virus" and how virologists talked about viruses. These changes reflected their invention and reinvention of the concept of a virus as it was revised in light of new knowledge, new scientific values and interests, and new hegemonic technologies. PMID:26958713

  8. Le pompage optique naturel dans le milieu astrophysique

    NASA Astrophysics Data System (ADS)

    Pecker, J.-C.

    The title of this lecture abstracts only a part of it : the importance in astrophysics of the study of non-LTE situations has become considerable, as well in the stellar atmospheres as, still more, in the study of fortuitous coincidences as a mechanism of formation of emission line nebular spectra, or of molecular interstellar « masers ». Another part of this talk underlines the role of Kastler in his time, and describes his warm personality through his public reactions in front of the nuclear armement, of the Viet-Nam and Algerian wars, of the problems of political refugees... Kastler was a great scientist ; he was also a courageous humanist. 1976 : Les accords nucléaires du Brésil : allocution d'ouverture (19 mars). Colloque sur le sujet ci-dessus. 1976 : La promotion de la culture dans le nouvel ordre économique international, allocution à l'occasion d'une table ronde sur ce thème par l'UNESCO (23-27 juin 1976) ; « Sciences et Techniques », octobre 1976. 1979 : La bête immonde (avec J.-C. Pecker), « Le Matin », 20 mars. 1979 : Appel à nos ministres (avec J.-C. Pecker), « Le Monde », 13 décembre. 1979 : Le flou, le ténébreux, l'irrationnel (avec J.-C. Pecker), « Le Monde », 14 septembre. 1980 : Education à la paix, Préface, in : Publ. UNESCO. 1981 : Le vrai danger, « Le Monde », 6 août 1981. 1982 : Nucléaire civil et militaire, « Le Monde », 1er juin 1982. 1982 : Les scientifiques face à la perspective d'holocauste nucléaire (texte inédit). Le titre de cette communication en résume seulement une partie : l'importance prise en astrophysique par l'analyse des situations hors ETL est devenue considérable, qu'il s'agisse des atmosphères stellaires, ou plus encore, des coïncidences fortuites de la formation des spectres d'émission nébulaires, ou des « masers » moléculaires interstellaires. Une autre partie de cet exposé souligne lele de Kastler dans son époque, et décrit sa personnalité généreuse à travers ses r

  9. Le système opioïde endogène et l’addiction aux drogues1

    PubMed Central

    Maldonado, Rafael

    2010-01-01

    Résumé L’addiction aux drogues est une maladie psychiatrique chronique qui conduit à d’importantes altérations adaptatives dans les circuits de récompense du cerveau. Plusieurs systèmes de neurotransmission sont impliqués dans ces modifications. Cependant, un des systèmes neurochimiques qui joue un rôle essentiel dans l’addiction est le système opioïde endogène. Les récepteurs opioïdes et les peptides opioïdes endogènes sont très largement présents dans les structures cérébrales qui contrôlent les phénomènes de récompense, en particulier le système mésolimbique. Ces récepteurs et peptides opioïdes participent d’une manière sélective à plusieurs aspects des processus addictifs induits par les opiacés, les cannabinoïdes, les psychostimulants, l’alcool et la nicotine. Cette revue rend compte de l’état actuel des connaissances sur la participation de chaque composante du système opioïde endogène dans les propriétés addictives des différentes drogues. PMID:20176158

  10. Biologic characterization of chicken-derived H6N2 low pathogenic avian influenza viruses in chickens and ducks

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In this study we biologically characterized H6N2 low pathogenicity avian influenza (LPAI) viruses by infecting chickens and ducks in order to compare adaptation of these viruses in these species. We examined the clinical signs, virus shedding, and immune response to infection in 4-week old white le...

  11. Les bisphosphonates dans le traitement de l’ostéoporose

    PubMed Central

    Brown, Jacques P.; Morin, Suzanne; Leslie, William; Papaioannou, Alexandra; Cheung, Angela M.; Davison, Kenneth S.; Goltzman, David; Hanley, David Arthur; Hodsman, Anthony; Josse, Robert; Jovaisas, Algis; Juby, Angela; Kaiser, Stephanie; Karaplis, Andrew; Kendler, David; Khan, Aliya; Ngui, Daniel; Olszynski, Wojciech; Ste-Marie, Louis-Georges; Adachi, Jonathan

    2014-01-01

    Résumé Objectif Exposer l’efficacité et les risques du traitement par les bisphosphonates dans la prise en charge de l’ostéoporose et décrire les patients qui seraient de bons candidats aux congés thérapeutiques. Qualité des données Une recherche dans MEDLINE (PubMed, jusqu’au 31 décembre 2012) a permis de relever les publications pertinentes pour l’inclusion. La plupart des données probantes citées sont de niveau II (tirées d’essais non randomisés, de cohorte et d’autres essais comparatifs). Message principal L’efficacité des bisphosphonates de premier recours homologués pour la prévention des fractures a été éprouvée dans le cadre d’essais cliniques randomisés et contrôlés. Cependant, l’usage clinique répandu et prolongé des bisphosphonates a donné lieu à des rapports de manifestations indésirables rares, mais graves. L’ostéonécrose maxillaire et les fractures atypiques sous-trochantériennes ou diaphysaires du fémur seraient liées à l’emploi des bisphosphonates dans le traitement de l’ostéoporose, mais ces manifestations sont extrêmement rares et lorsqu’elles surviennent, elles sont accompagnées d’autres comorbidités ou de l’emploi concomitant de médicaments. Les congés thérapeutiques ne peuvent être envisagés que chez les patients à faible risque et dans un groupe restreint de patients dont le risque de fracture est modéré après un traitement de 3 à 5 ans. Conclusion Lorsque les bisphosphonates sont prescrits à des patients dont le risque de fracture est élevé, leur effet de prévention des fractures l’emporte de loin sur leurs torts potentiels. Chez les patients qui prennent des bisphosphonates depuis 3 à 5 ans, il faut réévaluer le besoin de poursuivre le traitement.

  12. Le LHC, un tunnel cosmique

    ScienceCinema

    None

    2011-10-06

    Et si la lumière au bout du tunnel du LHC était cosmique ? En d?autres termes, qu?est-ce que le LHC peut nous apporter dans la connaissance de l?Univers ? Car la montée en énergie des accélérateurs de particules nous permet de mieux appréhender l?univers primordial, chaud et dense. Mais dans quel sens dit-on que le LHC reproduit des conditions proches du Big bang ? Quelles informations nous apporte-t-il sur le contenu de l?Univers ? La matière noire est-elle détectable au LHC ? L?énergie noire ? Pourquoi l?antimatière accumulée au CERN est-elle si rare dans l?Univers ? Et si le CERN a bâti sa réputation sur l?exploration des forces faibles et fortes qui opèrent au sein des atomes et de leurs noyaux, est-ce que le LHC peut nous apporter des informations sur la force gravitationnelle qui gouverne l?évolution cosmique ? Depuis une trentaine d?années, notre compréhension de l?univers dans ses plus grandes dimensions et l?appréhension de son comportement aux plus petites distances sont intimement liées : en quoi le LHC va-t-il tester expérimentalement cette vision unifiée ? Tout public, entrée libre / Réservations au +41 (0)22 767 76 76

  13. Zika Virus

    MedlinePlus

    ... Search The CDC Cancel Submit Search The CDC Zika Virus Note: Javascript is disabled or is not supported ... Areas with Zika Countries and territories with active Zika virus transmission... Mosquito Control Prevent mosquito bites, integrated mosquito ...

  14. Zika Virus

    MedlinePlus

    Zika is a virus that is spread by mosquitoes. A pregnant mother can pass it to her ... through blood transfusions. There have been outbreaks of Zika virus in Africa, Southeast Asia, the Pacific Islands, ...

  15. Zika Virus

    MedlinePlus

    Zika is a virus that is spread mostly by mosquitoes. A pregnant mother can pass it to ... through blood transfusions. There have been outbreaks of Zika virus in the United States, Africa, Southeast Asia, ...

  16. Chikungunya Virus

    MedlinePlus

    ... traveling to countries with chikungunya virus, use insect repellent, wear long sleeves and pants, and stay in ... Chikungunya Prevention is key! Prevent Infection. Use mosquito repellent. Chikungunya Virus Distribution Chikungunya in the U.S. What's ...

  17. Hepadna viruses

    SciTech Connect

    Robinson, W.; Koike, K.; Will, H.

    1987-01-01

    This book examines the molecular biology, disease pathogenesis, epidemiology, and clinical features of hepadna and other viruses with hepatic tropism and outlines future directions and approaches for their management. The volume's six sections provide a review of the various features, mechanisms, and functions of these viruses, ranging from hepadna virus replication and regulation of gene expression to the structure and function of hepadna-virus gene products.

  18. ECHO virus

    MedlinePlus

    Enteric cytopathic human orphan (ECHO) viruses are a group of viruses that lead to gastrointestinal infection and skin rashes. ... Echovirus is one of several families of viruses that affect the ... are common. In the United States, they are most common in ...

  19. Le Planetaire (Around the World)

    ERIC Educational Resources Information Center

    Rebouillet, Andre; And Others

    1977-01-01

    This section, "Le Planetaire," contains an interview with Anne Slack on the American Association of Teachers of French and contemporary French culture, a review of a dictionary of familiar French for students, dates to remember, events of interest to French teachers and a general bibliography. (Text is in French.) (AMH)

  20. Le don après un décès d'origine cardiocirculatoire au Canada

    PubMed Central

    Shemie, Sam D.; Baker, Andrew J.; Knoll, Greg; Wall, William; Rocker, Graeme; Howes, Daniel; Davidson, Janet; Pagliarello, Joe; Chambers-Evans, Jane; Cockfield, Sandra; Farrell, Catherine; Glannon, Walter; Gourlay, William; Grant, David; Langevin, Stéphan; Wheelock, Brian; Young, Kimberly; Dossetor, John

    2006-01-01

    engagement des intervenants, mécanismes d'assurance de la sécurité et de la qualité et information du public. Il est recommandé de commencer par un program de DDC contrôlé à l'unité de soins intensifs où, après une décision par consentement mutuel de cesser le traitement de maintien des fonctions vitales, la mort est attendue, mais n'est pas survenue, ce qui rend possible des discussions non précipitées sur le consentement. Un don non contrôlé, en cas de décès après un arrêt cardiaque non prévu, doit être envisagé seulement une fois que le program de DDC contrôlé a été établi. Bien qu'il soit recommandé de restreindre le programme initial au don de reins, le don d'autres organes peut aussi être envisagé selon l'expertise régionale en matière de transplantation. Les répercussions d'un DDC, y compris les interventions pratiquées avant et après le décès, sur la famille du donneur, la disponibilité des organes, la fonction du greffon et la survie du receveur doivent être documentées de façon méthodique et examinées.

  1. Etude de l'effet du vieillissement sur les proprietes d'un tissu en melange KevlarRTM-PBI utilise dans le revetement exterieur des habits de protection contre le feu

    NASA Astrophysics Data System (ADS)

    Arrieta, Carlos

    The aim of this work is to study and model the effect of three aging factors, temperature, humidity and light radiation, on the properties of a fabric made of a blend of KevlarRTM and PBI fibers frequently used to manufacture fire-protective garments. Accelarated-aging treatments carried out at carefully chosen conditions for the three factors resulted in a sizeable loss of mechanical performance. The breaking force of both the fabric and the yarns extracted from it decreases to less than 50% after one month of continuous exposure. X-ray diffraction (XRD) tests performed on thermally-aged samples indicated an increase of the crystallinity of the fabric, whereas the disappearance of Raman spectral lines suggested instead a reduction of the crystallinity following thermal aging. To explain these seemingly contradictory results, a hypothesis was introduced, stating that two different processes occurred simultaneously during thermal aging. The first one, an increase of size of the crystallites in the direction of the fibers' axis, accounted for the increase in crystallinity observed in XRD tests. The second one, an increase in the gap separating lamellar crystallites that causes a non-measurable reduction of the crystallinity of the sample, was highlighted by the Raman analyses. The results of the dielectric spectroscopy analyses carried out on thermally-aged samples confirmed the XRD results showing a significant change in the Kevlar's morphology during thermal aging. Despite the important decrease of the breaking force that ensued thermal aging, no evidence of a chemical structure modification of KevlarRTM was found. On the other hand, differential thermal analyses conducted on thermally aged fabric samples indicated a reduction of the glass transition temperature of the other component of the blend, namely the PBI, a fact that suggests a decrease of molecular weight after thermal aging. Infrared spectroscopy analyses performed on samples exposed to high humidity levels showed the development of a new absorbing band in the spectrum of aged KevlarRTM yarns. This band was ascribed to the formation of carboxylic acid groups. Based on these results, the humidity aging mechanism was inferred. This mechanism corresponds to the hydrolysis of the amide bond of KevlarRTM catalyzed by an acid. The progress of the hydrolysis reaction was modeled mathematically using the evolution of the concentration of carboxylic acid groups. The mechanism of light radiation aging was also determined from infrared spectroscopy analyses as the absorbing band attributed to the carboxylic acid groups was once again observed. In the case of light radiation, the degradation mechanism corresponds to a photo-oxidation reaction initiated by the photolysis of the amide bond of KevlarRTM. The accumulation of Photo-Fries products on the surface of yarns is believed to slow down of the oxidation reaction, as indicated by the overlapping of breaking force vs. aging time curves for the light-radiation aged samples. Expressions based on the Arrhenius law were used to characterize both the thermal and hydrolytic aging, whereas an expression taking into account the irradiance as well as the temperature was used to model the light radiation aging. The global damage produced by the joint action of the three aging factors was modeled after Palmgren-Miner's linear cumulative damage theory.

  2. Le Silurien de la région d'Oulad Abbou (Meseta occidentale, Maroc) : une sédimentation péritidale sous contrôle tectonique

    NASA Astrophysics Data System (ADS)

    Attou, Ahmed; Hamoumi, Naima

    2004-07-01

    In the Oulad Abbou syncline, western coastal Meseta, the Silurian deposits exhibit siliciclastic or mixed siliciclastic/carbonate tidal facies that recorded alkaline basalt flows and syn-sedimentary deformations. These facies are staked into peritidal shallowing upward sequences reflecting the evolution from an infratidal to a supratidal environment. These sequences recorded low-amplitude and high-frequency sea-level variations. The built-up of these rhythmic sequences is related to distensive tectonic that allowed the development of isolated platform from extensive siliciclastic influx. This tectonic event is well recorded in the palaeogeographic evolution of the northern Gondwana platform during the Lower Palaeozoic time. To cite this article: A. Attou, N. Hamoumi, C. R. Geoscience 336 (2004).

  3. Prévalence du tabagisme chez le personnel de l'Hôpital Général de Douala, Cameroun

    PubMed Central

    Mbatchou Ngahane, Bertrand Hugo; Luma, Henry; Ndiaye, Mor; Njankouo, Yacouba Mapoure; Mbahe, Salomon; Wandji, Adeline; Temfack, Elvis; Mouelle Sone, Albert; Dautzenberg, Bertrand

    2012-01-01

    Introduction La prévalence du tabagisme parmi le personnel de santé hospitalier au Cameroun n'est pas connue alors que le tabagisme est en expansion dans ce pays avec 13,2% de fumeurs selon l'OMS. Pour combler ce manque une enquête sur les consommations, les connaissances, opinions et attitudes vis-à-vis des fumeurs a été conduite à l'Hôpital Général de Douala, l'un des hôpitaux de référence du Cameroun. Méthodes Du 1er au 30 Avril 2010, des questionnaires anonymes ont été distribués par des enquêteurs dans les services ou via les surveillants et recueillis et analysés de façon anonyme. Résultats Sur 402 questionnaires distribués 277 ont été récupérés. La prévalence de fumeurs est de 3,6% parmi les soignants et de 9,4% parmi les autres personnels soit en moyenne sur l'ensemble de l'hôpital 5,4%. Les produits fumés étaient toujours des cigarettes. L'initiation du tabagisme à souvent été tardive (21,5 ans) et la dépendance est absente ou faible chez 33% des fumeurs. Les personnes pensent que c'est leur devoir de questionner sur le tabac et de prendre en charge les fumeurs, mais ils sont presque un sur deux à ignorer la loi Camerounaise. Conclusion Le tabagisme chez le personnel hospitalier est une réalité au Cameroun; le personnel soignant et les pouvoirs publics devraient s'impliquer davantage dans la lutte contre ce fléau qui est en expansion dans les pays du sud. PMID:22514759

  4. In re LePage.

    PubMed

    2001-01-01

    Court Decision: 18 Pacific Reporter, 3d Series 1177; 2001 Mar 8 (date of decision). The Supreme Court of Wyoming held that the state Department of Health was not authorized to inquire about the sincerity of a mother's religious beliefs when determining whether her daughter was exempt from a public school immunization requirement. Susan LePage submitted a request to the Department of Health seeking to exempt her daughter from receiving the hepatitis B vaccination. The Department of Health inquired into the sincerity of LePage's religious beliefs against vaccination and determined that her objections were of a personal or philosophical nature and not on religious grounds. The Department of Health denied LePage's request. The Supreme Court of Wyoming held that state law requires the Department of Health to grant an exemption upon the submission of a written objection and does not allow the Department of Health to make an inquiry into the sincerity of the requestor's religious beliefs. The court balanced a valid state interest in protecting schoolchildren from disease with the relatively low number of requests for exemption and its confidence in parents to make decisions in the best interest of their children's physical and spiritual health. Since there was no justification within the statute to allow a religious inquiry, the court held that the Department of Health had exceeded its authority with LePage. Furthermore, state law did not require a religious waiver to exempt a child from this particular vaccine. The lower court's holding was reversed. PMID:16479706

  5. Zika virus.

    PubMed

    2016-02-10

    Essential facts Zika virus disease is caused by a virus that is transmitted by the Aedes mosquito. While it generally causes a mild illness, there is increasing concern that it is harmful in pregnancy and can cause congenital abnormalities in infants born to women infected with the virus. There is no antiviral treatment or vaccine currently available. The best form of prevention is protection against mosquito bites. PMID:26860150

  6. CHLORELLA VIRUSES

    PubMed Central

    Yamada, Takashi; Onimatsu, Hideki; Van Etten, James L.

    2007-01-01

    Chlorella viruses or chloroviruses are large, icosahedral, plaque‐forming, double‐stranded‐DNA—containing viruses that replicate in certain strains of the unicellular green alga Chlorella. DNA sequence analysis of the 330‐kbp genome of Paramecium bursaria chlorella virus 1 (PBCV‐1), the prototype of this virus family (Phycodnaviridae), predict ∼366 protein‐encoding genes and 11 tRNA genes. The predicted gene products of ∼50% of these genes resemble proteins of known function, including many that are completely unexpected for a virus. In addition, the chlorella viruses have several features and encode many gene products that distinguish them from most viruses. These products include: (1) multiple DNA methyltransferases and DNA site‐specific endonucleases, (2) the enzymes required to glycosylate their proteins and synthesize polysaccharides such as hyaluronan and chitin, (3) a virus‐encoded K+ channel (called Kcv) located in the internal membrane of the virions, (4) a SET domain containing protein (referred to as vSET) that dimethylates Lys27 in histone 3, and (5) PBCV‐1 has three types of introns; a self‐splicing intron, a spliceosomal processed intron, and a small tRNA intron. Accumulating evidence indicates that the chlorella viruses have a very long evolutionary history. This review mainly deals with research on the virion structure, genome rearrangements, gene expression, cell wall degradation, polysaccharide synthesis, and evolution of PBCV‐1 as well as other related viruses. PMID:16877063

  7. Le Fevre [Le Fèvre; LeFebvre], Jean (1652-1706)

    NASA Astrophysics Data System (ADS)

    Murdin, P.

    2000-11-01

    Born in Lisieux, France, became an associate of JEAN PICARD and PHILIPPE DE LA HIRE, became a member of the Académie des Sciences and worked on rather routine work calculating ephemeredes, and surveying. Le Fevre accused La Hire of stealing his tables after Philippe de La Hire published Tabulae Astronomicae in 1687. In 1701, resentful at not having been named official publisher of ephemerides to ...

  8. Live Virus Smallpox Vaccine

    MedlinePlus

    ... Index SMALLPOX FACT SHEET The Live Virus Smallpox Vaccine The vaccinia virus is the "live virus" used ... cannot cause smallpox. What is a "live virus" vaccine? A "live virus" vaccine is a vaccine that ...

  9. Portevin-Le chatelier effect

    PubMed

    Franklin; Mertens; Marder

    2000-12-01

    Aluminum subjected to smooth mechanical loading does not often deform in a correspondingly smooth manner. Typically it deforms inhomogeneously through the propagation of deformation fronts that slowly traverse the sample. These are called Portevin-Le Chatelier fronts; what determines their velocity has been somewhat mysterious. We present a phenomenological theory for deformation fronts that centers on a nonlocal rate dependence of the flow stress. In a one-dimensional idealization the equations can be solved exactly, and compared directly with experiment. Many significant features of deformation fronts are captured, including a well-known transition from hopping to continuous front motion. The phenomenology's predictions are confirmed by our experiments. PMID:11138118

  10. Protection des ions organiques contre les dommages induits a l'ADN par les electrons de basse energie

    NASA Astrophysics Data System (ADS)

    Dumont, Ariane

    Il a ete demontre que les electrons de basse energie (EBE) peuvent induire des cassures simple brin (CSB) a l'ADN, via la formation d'anions transitoires qui decroissent par attachement dissociatif, ou dans d'autres etats electroniques dissociatifs menant a la fragmentation. Afin d'effectuer une etude complete des effets des electrons de basse energie sur la matiere biologique, il est necessaire de comprendre leur mecanismes d'interaction non seulement avec l'ADN, mais avec les constituants de son environnement. Les histones sont une composante importante de l'environnement moleculaire de l'ADN. Leur charge positive leur permet de s'associer aux groupements phosphate anionique de l'ADN. Le role principal de ces proteines basiques consiste a organiser l'ADN et l'empaqueter afin de former la chromatine. Les cations sont une autre composante importante de la cellule; ils jouent un role dans la stabilisation de la conformation B de l'ADN in vitro par leurs interactions avec les petits et grands sillons de l'ADN, ainsi qu'avec le groupement phosphate charge negativement. Avec les histones, ils participent egalement a la compaction de l'ADN pour former la chromatine. Cette etude a pour but de comprendre comment la presence d'ions organiques (sous forme de Tris et d'EDTA) a proximite de l'ADN modifie le rendement de cassures simple brin induit par les electrons de basse energie. Le Tris et l'EDTA ont-ete choisis comme objet d'etude, puisqu'en solution, ils forment le tampon standard pour solubiliser l'ADN dans les experiences in vitro (10mM Tris, 1mM EDTA). De plus, la molecule Tris possede un groupement amine alors que l'EDTA possede 4 groupements carboxyliques. Ensembles, ils peuvent se comporter comme un modele simple pour les acides amines. Le ratio molaire de 10 :1 de Tris par rapport a l'EDTA a pour but d'imiter le comportement des histones qui sont riches en arginine et lysine, acides amines possedant un groupement amine charge positivement additionnel. Des films d

  11. Diseases Caused by Viruses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The symptoms, causal agents, epidemiology and management of important virus diseases in chickpea and lentil crops were reviewed in depth. The virus diseases include.Alflafa mosaic virus, Cucumber mosaiv virus, Faba bean necrotic yellows virus, Pea enation mosaic virus, Pea seed-borne mosaci virus,...

  12. Facteurs de risque dans le trouble déficitaire de l’attention et de l’hyperactivité: étude familiale

    PubMed Central

    Poissant, Hélène; Rapin, Lucile

    2012-01-01

    Résumé Objectif: Notre étude a pour but d’évaluer les facteurs de risque associés au trouble déficitaire de l’attention et de l’hyperactivité (TDAH) en termes de comorbidités et de facteurs d’adversité à l’intérieur des familles avec un TDAH. Méthodologie: 137 parents de 104 enfants avec un TDAH et 40 parents de 34 enfants contrôles ont répondu aux items d’un questionnaire. Des tests Chi-carrés et des tests de Student ont mesuré l’association de chaque item avec les groupes et les différences entre les groupes. Résultats: Les enfants avec un TDAH avaient des performances scolaires plus faibles et une plus forte prévalence des troubles d’apprentissage, oppositionnel, des conduites et anxieux que celle des enfants contrôles. Des difficultés d’apprentissage étaient plus souvent rapportées chez les pères d’enfants avec un TDAH. Par ailleurs, l’isolement social et les accidents de la route étaient davantage présents chez les mères d’enfants avec un TDAH. Ces dernières souffraient plus de dépression et de trouble anxieux et prenaient davantage de médicaments que les mères contrôles. Conclusion: L’étude de facteurs de risque révèle un lien entre les parents et les enfants, spécifiquement la présence de dépression parmi les mères d’enfants avec un TDAH et de difficultés d’apprentissage chez les pères, suggérant une composante familiale dans le trouble. La sous-représentation du TDAH chez les pères d’enfants avec un TDAH est discutée. PMID:23133459

  13. Faut-il continuer à infiltrer le scalp par un anesthésique local pour une craniotomie?

    PubMed Central

    Doumiri, Mouhssine; Motiaa, Youssef; Razine, Rachid; Amor, Morad; Moussaoui, Abdelmajid; Kabbaj, Saad; Maazouzi, Wajdi

    2015-01-01

    Introduction Le maintien de la stabilité hémodynamique est un objectif primordial de l'anesthésie pour craniotomie. Peu d’études ont prouvé l'efficacité de l'infiltration du scalp par un anesthésique local pour le maintien de la stabilité hémodynamique après l'incision. L'objectif de notre travail est d’évaluer l'influence de l'infiltration de la ligne d'incision du scalp par la lidocaïne à 0,5% adrénalinée sur les paramètres hémodynamiques après incision pour craniotomie supratentorielle. Méthodes Étude prospective en double aveugle réalisée au bloc opératoire de l'hôpital des spécialités de Rabat sur une période d'une année incluant 80 malades programmés pour craniotomie supratentorielle. Les malades étaient randomisés par tirage au sort en 2 groupes: Le groupe 1 était infiltré par 40 ml du sérum salé adrénaliné (1/200 000) et le groupe 2 était infiltré par 40 ml de la lidocaïne 0,5% adrénalinée (1/200 000). Le critère de jugement principal était la pression artérielle moyenne (PAM) après l'incision. L’étude statistique a fait appel aux tests t de student et l'U- mann-whitney. Une valeur de p <0.05 était considérée significative. Résultats L’étude a inclus 80 patients (40 hommes et 40 femmes). L’âge moyen était 42,33±14,76 ans. Le poids moyen était 71,58 ±10 kg. Le 3/4 des patients était ASA 1, seulement 25% étaient ASA2. La durée moyenne de la chirurgie était de 252,06±38,62 mn. Les deux groupes étaient comparables concernant l’âge, le sexe, le poids, la durée d'intervention, le type d'abord chirurgical, la dose totale du fentanyl reçue jusqu'a l'incision, ainsi que les paramètres hémodynamiques avant l'incision. Après l'incision la FC moyenne a augmenté dans les deux groupes: 80,53±7,72 bpm dans le groupe contrôle et 76,85±8,52 bpm dans le groupe lidocaïne. La différence d'augmentation de la FC entre les deux groupes était statistiquement significative (p = 0,047). L

  14. Computer viruses

    NASA Technical Reports Server (NTRS)

    Denning, Peter J.

    1988-01-01

    The worm, Trojan horse, bacterium, and virus are destructive programs that attack information stored in a computer's memory. Virus programs, which propagate by incorporating copies of themselves into other programs, are a growing menace in the late-1980s world of unprotected, networked workstations and personal computers. Limited immunity is offered by memory protection hardware, digitally authenticated object programs,and antibody programs that kill specific viruses. Additional immunity can be gained from the practice of digital hygiene, primarily the refusal to use software from untrusted sources. Full immunity requires attention in a social dimension, the accountability of programmers.

  15. Hendra virus.

    PubMed

    Middleton, Deborah

    2014-12-01

    Hendra virus infection of horses occurred sporadically between 1994 and 2010 as a result of spill-over from the viral reservoir in Australian mainland flying-foxes, and occasional onward transmission to people also followed from exposure to affected horses. An unprecedented number of outbreaks were recorded in 2011 leading to heightened community concern. Release of an inactivated subunit vaccine for horses against Hendra virus represents the first commercially available product that is focused on mitigating the impact of a Biosafety Level 4 pathogen. Through preventing the development of acute Hendra virus disease in horses, vaccine use is also expected to reduce the risk of transmission of infection to people. PMID:25281398

  16. L'astronomie dans le monde

    NASA Astrophysics Data System (ADS)

    Manfroid, J.

    2008-09-01

    Fragmentation et astéroïdes binaires; Astéroïde géocroiseur triple; Rosetta sort de son hibernation; Messenger; Transit lunaire vu par Deep Impact; Titan; Phobos; Phoenix; Einstein avait raison; Le ballet des taches rouges; Le poids des lentilles;

  17. Characterisation of lettuce virus X, a new potexvirus infecting lettuce in Iran.

    PubMed

    Dizadji, A; Koohi-Habibi, M; Izadpanah, K; Dietrich, C; Mossahebi, G H; Winter, S

    2008-01-01

    A virus with flexuous rod-shaped particle morphology was found in samples from lettuce during a survey of viruses infecting lettuce in Tehran province in Iran. This virus was subjected to a complete analysis of its biological and molecular features. The entire nucleotide sequence of the virus was determined, revealing a polyadenylated ssRNA genome consisting of 7,212 nucleotides [without poly (A) tail] and possessing an organization typical for potexviruses. Comparative genome analysis showed that the lettuce virus is closely related to Alstroemeria virus X, narcissus mosaic virus and asparagus virus 3. Based on particle morphology, physico-chemical properties and the complete genome sequence, this virus is a member of a new species in the genus Potexvirus, for which the name lettuce virus X (LeVX) is proposed. Biological assays using an infectious cDNA clone and a wild-type isolate of LeVX revealed that the virus, despite reaching high concentrations in all lettuce cultivars tested, does not cause symptoms in lettuce. PMID:18807116

  18. Zika Virus

    MedlinePlus

    ... be at risk for developing fetal complications. Blood, organ and tissue donor screening tests are also needed to assure the safety of transfusion and transplantation in areas of active mosquito-borne virus transmission. ...

  19. Zika Virus.

    PubMed

    Phillips, Jennan A; Neyland, Anavernyel

    2016-08-01

    Zika virus (ZIKV) infections are the latest global public health emergency. Occupational health nurses can protect society by educating workers, women of childbearing age, and others traveling in ZIKV-infected areas about prevention strategies. PMID:27411846

  20. Le syndrome d'apert

    PubMed Central

    Benmiloud, Sarra; Chaouki, Sana; Atmani, Samir; Hida, Moustapha

    2013-01-01

    Le syndrome d'Apert est une affection congénitale rare, caractérisée par une sténose cranio-faciale associée à une syndactylie des mains et des pieds. Sa prise en charge doit être précoce et multidisciplinaire. Sa gravité réside dans la coexistence de plusieurs malformations avec un risque d'hypertension intracrânienne chronique responsable d'une cécité et d'une débilité mentale. Les auteurs rapportent une nouvelle observation à travers laquelle ils illustrent les aspects cliniques et évolutifs ainsi que les difficultés thérapeutiques de cette affection. PMID:23565313

  1. Intraday LeBaron effects

    PubMed Central

    Bianco, Simone; Corsi, Fulvio; Renò, Roberto

    2009-01-01

    We study the relation at intraday level between serial correlation and volatility of the Standard and Poor (S&P) 500 stock index futures returns. At daily and weekly levels, serial correlation and volatility forecasts have been found to be negatively correlated (LeBaron effect). After finding a significant attenuation of the original effect over time, we show that a similar but more pronounced effect holds by using intraday measures, by such as realized volatility and variance ratio. We also test the impact of unexpected volatility, defined as the part of volatility which cannot be forecasted, on the presence of intraday serial correlation in the time series by employing a model for realized volatility based on the heterogeneous market hypothesis. We find that intraday serial correlation is negatively correlated to volatility forecasts, whereas it is positively correlated to unexpected volatility.

  2. Syndrome métabolique chez les patients hypertendus dans le service cardiologie du CHU Yalgado Ouedraogo de Ouagadougou, Burkina Faso

    PubMed Central

    Millogo, Georges Rosario Christian; Samandoulougou, André; Yaméogo, Nobila Valentin; Yaméogo, Aristide Relwendé; Kologo, Koudougou Jonas; Toguyeni, Jean Yves; Zabsonré, Patrice

    2014-01-01

    Introduction Le syndrome métabolique constitue de nos jours un véritable problème de santé publique. Le syndrome métabolique est le moteur d'une double épidémie mondiale de diabète type II et de maladies cardiovasculaires. L'objectif de notre étude est de décrire les aspects épidémiologiques, cliniques, para cliniques et évolutifs chez les hypertendus dans le service de Cardiologie du CHU Yalgado Ouédraogo. Méthodes Il s'agissait d'une étude rétrospective sur une période de deux ans dans le service de cardiologie chez les patients hypertendus ayant un syndrome métabolique. Résultats La fréquence du syndrome métabolique était de 17,5% des patients hypertendus. Le sex ratio était de 1,2. L’âge moyen des patients étaient de 56,1 ±10,7 ans. Les patients connus hypertendus étaient de 92,1% avec une durée moyenne d’évolution de l'HTA qui était de 8,7 ± 5,9 ans. Le suivi était irrégulier dans 60% cas et une rupture du traitement dans 37,1% des cas. La dyslipidémie était notée dans 84,2% des cas et le diabète dans 60,5% des cas. La PAS moyenne était de 184,3 ± 47,3 mmHg et la PAD moyenne était de 110,7 ± 27,7 mmHg. L'HTA était sévère dans 63,2% des cas. La glycémie moyenne était de 8,3 ± 4,3 mmol/L, le LDL cholestérol moyen était de 3,5 ± 1,0 mmol/L et le taux des triglycérides moyen était de 1,6 ± 1,1 mmol/L. L'HVG électrique était notée chez 76,3% des patients et échographique dans 58,8% des cas. Les atteintes viscérales étaient neurologique dans 44,5%, rénale dans 55,3% et cardiaque dans 31,2% des cas. Le nombre moyen d'antihypertenseurs était de 3,0 ± 1,0 et 76,3% ont reçu au moins une trithérapie antihypertensive. Le taux de mortalité était de 5,3%. Conclusion Le syndrome métabolique est une pathologie qui pose la problématique de la définition qui n'est pas consensuelle d'une part et d'autre part du contrôle de ses éléments constitutifs surtout l'HTA. PMID:25883718

  3. Profil bactériologique du pied diabétique et son impact sur le choix des antibiotiques

    PubMed Central

    Zemmouri, Adil; Tarchouli, Mohamed; Benbouha, Abdellatif; Lamkinsi, Tarik; Bensghir, Mustapha; Elouennass, Mostafa; Haimeur, Cherqui

    2015-01-01

    Introduction Analyse du profil bactériologique des pieds diabétiques pris en charge à l'hôpital militaire de Rabat et son influence sur l'antibiothérapie de première intention. Méthodes Etude prospective non randomisée étalée sur 18 mois, ayant concerné 105 patients. Après recueil des données et en attente des résultats bactériologiques nos patients ont été divisés en deux groupes: un groupe a été mis sous Amoxicilline + Acide clavulanique + Gentamycine (59 patients) et un groupe sous Ertapénème±Gentamycine (46 patients). Résultats L’étude a regroupé 85 hommes et 20 femmes (sexe ratio = 4.26). L’âge moyen est de 64.4 ans. La gangrène a été observée chez 79% des malades; elle était humide-donc surinfectée en principe- dans 43% des cas. Par ailleurs, 67% des malades ont un chiffre de globules blancs 12000 définissant une infection sévère. L'ostéolyse a été mise en évidence chez 27% de nos patients. Parmi les différentes techniques de prélèvements: 81% ont été profonds dont 21% de biopsie osseuse per opératoire et 14% de prélèvements combinés. 42% de ces prélèvements sont poly microbiens et 21% sont stériles. Les résultats bactériologiques viennent confirmer la prédominance des bactéries aérobies à Gram positif. Le taux de remplacement de l'Ertapénème est de 22% contre un taux de 50% pour l'Amoxiclav. Conclusion L'antibiothérapie ne doit être instaurée qu'en cas d'infection du pied diabétique diagnostiquée sur les critères cliniques établis par les consensus internationaux récents. Le respect des mesures de lutte contre la diffusion de la résistance bactérienne s'avère primordiale. PMID:27386024

  4. Recommandations pour le dépistage de l’hypertension chez les adultes canadiens

    PubMed Central

    Lindsay, Patrice; Gorber, Sarah Connor; Joffres, Michel; Birtwhistle, Richard; McKay, Donald; Cloutier, Lyne

    2013-01-01

    Résumé Objectif Présenter des recommandations concernant le dépistage de l’hypertension chez les adultes de 18 ans et plus qui n’ont pas reçu antérieurement de diagnostic d’hypertension. Qualité des données Les données probantes sont tirées d’une recension systématique dans MEDLINE, EMBASE et la base de données des synthèses systématiques de la Collaboration Cochrane (EBM Reviews), de janvier 1985 à septembre 2011. Les types d’études retenues se limitaient aux études randomisées contrôlées, aux synthèses systématiques et aux études observationnelles avec groupes témoins. Message principal Trois fortes recommandations se sont dégagées de données probantes de qualité modérée. Il est recommandé de mesurer la pression artérielle à toutes les consultations appropriées en soins primaires, conformément aux techniques actuelles décrites dans les recommandations du Programme éducatif canadien sur l’hypertension pour la mesure de la pression artérielle en cabinet et en soins ambulatoires. Les critères du Programme éducatif canadien sur l’hypertension pour l’évaluation et le diagnostic de l’hypertension devraient s’appliquer aux personnes chez qui on observe une pression artérielle élevée. Conclusion À la suite d’un examen des plus récentes données probantes, le Groupe d’étude canadien sur les soins de santé préventifs continue de recommander la mesure de la pression artérielle lors des consultations périodiques auprès du médecin.

  5. Computer Viruses. Technology Update.

    ERIC Educational Resources Information Center

    Ponder, Tim, Comp.; Ropog, Marty, Comp.; Keating, Joseph, Comp.

    This document provides general information on computer viruses, how to help protect a computer network from them, measures to take if a computer becomes infected. Highlights include the origins of computer viruses; virus contraction; a description of some common virus types (File Virus, Boot Sector/Partition Table Viruses, Trojan Horses, and…

  6. Profil comparatif et évolutif des personnes infectées par le virus de l'immunodéficience humaine traitées aux antirétroviraux à Kinshasa, République Démocratique du Congo

    PubMed Central

    Koy, Tshingani; Mukumbi, Henri; Malandala, Ghislain Lubangi Muteba; Donnen, Philippe; Wilmet–Dramaix, Michèle

    2014-01-01

    Introduction A trithérapie (ARV) introduite en R.D.Congo en 1996, a permis l′amélioration substantielle de la qualité de vie des PVVIH et a réduit la morbimortalité liée au sida en R.D. Congo. L'objectif de cette étude est de présenter le profil épidémiologique comparatif, clinique, ainsi que l’évolution anthropométrique des PVVIH sous ARV à Kinshasa. Méthodes Etude de cohorte sur 438 PVVIH, de 18 ans et plus, suivies entre mai 2010 à 2011 à Amo Congo à Kinshasa. Une comparaison a été faite entre les patients suivis pendant un an et ceux perdus de vue. Le Chi carré de Mc Nemar et l'analyse de variance pour mesures répétées ont été appliqués pour étudier l’évolution. Résultats Près 12 mois de suivi, 11,4% de patients ont été perdus de vue. Parmi eux, on observait des proportions significativement plus élevées de personnes de niveau socioéconomique bas, d'indice de masse corporelle (IMC) bas, présentant de l'anorexie, des affections opportunistes. Les proportions de patients aux stades OMS 3 & 4 et naïfs étaient également significativement plus élevées et la durée sous ARV plus courte. Les gains moyens des paramètres anthropométriques au 12ème mois, étaient importants: de 3,6 [3,2 - 4,0] kg pour le poids, 1,8 (1,4 - 2,3) cm pour le périmètre abdominal, 0,9 (0,8 - 1,2) cm pour le périmètre brachial, 1,4 (1,2 - 1,5) kg/m2 pour l'IMC. La proportion de patients avec un IMC <18,5 kg/m2 a significativement plus baissé entre l'admission et le 12ème mois parmi les patients sans stomatite que parmi ceux avec stomatite. L'IMC moyen évoluait significativement différemment entre l'admission et le 12ème mois selon l’âge et la taille de ménage. Conclusion Les facteurs fragilisant la rétention des patients sous antirétroviraux et une évolution progressive de l’état nutritionnel ont été observés. PMID:25995784

  7. Parainfluenza Viruses

    PubMed Central

    Henrickson, Kelly J.

    2003-01-01

    Human parainfluenza viruses (HPIV) were first discovered in the late 1950s. Over the last decade, considerable knowledge about their molecular structure and function has been accumulated. This has led to significant changes in both the nomenclature and taxonomic relationships of these viruses. HPIV is genetically and antigenically divided into types 1 to 4. Further major subtypes of HPIV-4 (A and B) and subgroups/genotypes of HPIV-1 and HPIV-3 have been described. HPIV-1 to HPIV-3 are major causes of lower respiratory infections in infants, young children, the immunocompromised, the chronically ill, and the elderly. Each subtype can cause somewhat unique clinical diseases in different hosts. HPIV are enveloped and of medium size (150 to 250 nm), and their RNA genome is in the negative sense. These viruses belong to the Paramyxoviridae family, one of the largest and most rapidly growing groups of viruses causing significant human and veterinary disease. HPIV are closely related to recently discovered megamyxoviruses (Hendra and Nipah viruses) and metapneumovirus. PMID:12692097

  8. Coût clinique des retards dans le changement de traitement

    PubMed Central

    Walmsley, Sharon

    2007-01-01

    La prise en charge des patients séropositifs pour le VIH ayant déjà reçu un traitement continue de s’améliorer et d’évoluer. Les nouvelles lignes directrices semblent indiquer que l’objectif du traitement devrait être une suppression virologique maximale. La meilleure façon d’y parvenir consiste à utiliser une combinaison d’agents auxquels le virus sera le plus vraisemblablement sensible et, si possible, des agents appartenant à une nouvelle classe thérapeutique. Les cas discutés démontrent comment l’utilisation d’un schéma thérapeutique puissant à titre de traitement de sauvetage peut avoir de bons résultats virologiques, immunologiques et cliniques. Toutefois, si le traitement de sauvetage retenu n’est pas assez puissant pour atteindre ces objectifs, la durabilité de la réponse est limitée. Ce qu’il faut retenir ici, c’est que ces stratégies devraient reposer sur la puissance du schéma thérapeutique et qu’il ne faut pas retarder l’instauration des agents en cas d’échec d’une stratégie.

  9. LeSTIG1, an extracellular binding partner for the pollen receptor kinases LePRK1 and LePRK2, promotes pollen tube growth in vitro.

    PubMed

    Tang, Weihua; Kelley, Dior; Ezcurra, Inés; Cotter, Robyn; McCormick, Sheila

    2004-08-01

    As pollen tubes grow through the pistil they are thought to perceive and respond to diverse signals. The tomato pollen-specific receptor kinases LePRK1 and LePRK2 might participate in signaling during pollen tube growth. We previously showed that the extracellular domain of LePRK2 interacts with a pollen protein, LAT52, before but not after pollen germination. To determine whether LePRK2 might have different binding partner(s) after pollen germination, we characterized two more proteins that, like LAT52, were identified in yeast two-hybrid screens using the extracellular domains of LePRK1 and LePRK2 as baits. We show that LeSHY, a leucine-rich repeat protein from pollen, and LeSTIG1, a small cysteine-rich protein from pistil, can bind the extracellular domains of both LePRK1 and LePRK2 in vitro. In vitro binding assays with the extracellular domain of LePRK2 suggested that LeSTIG1 could displace binding of LAT52, consistent with the idea that LePRK1 and LePRK2 might interact with different ligands at different stages of pollen tube growth. Exogenous LeSTIG1 promotes pollen tube growth in vitro. The interaction of these pollen kinases with LeSTIG1 supports the notion that LePRK1 and LePRK2 are involved in mediating pollen-pistil interactions. PMID:15255864

  10. Jan Potocki et le "Gothic Novel"

    ERIC Educational Resources Information Center

    Finne, Jacques

    1970-01-01

    Establishes a parallel between the supernatural and fantastic qualities of Le Comte Jan Potocki's literary works, and the English gothic novels by comparing the elements of terror, mysterious atmosphere, and the supernatural beings involved. (DS)

  11. Le syndrome de la pince aorto-mésentérique chez l'enfant: à propos d'un cas primitive

    PubMed Central

    Fall, Mbaye; Bâ, Papa Abdoulaye; Touré, Fodé Baba; Mbaye, Pape Alassane; Ngom, Gabriel

    2014-01-01

    Le syndrome de la pince aorto-mésentérique résulte de la compression du troisième duodénum entre l'artère mésentérique supérieure et l'aorte. Elle détermine un tableau d'occlusion intestinale haute aiguë ou chronique. Nous faisons une revue de la littérature à partir d'un cas de syndrome de la pince aorto-mésentérique. Il s'agit d'un nourrisson de 16 mois suivi pour des vomissements alimentaires évoluant depuis l’âge de 03 mois et rebelles au traitement médical. Il s'agit de vomissements postprandiaux tardifs d'apparition intermittente, améliorés par la position de décubitus ventral. Le bilan radiologique composé d'une radiographie de l'abdomen sans préparation, d'un transit oeso-gastroduodénal (TOGD) et d'un angioscanner a permis d'aboutir au diagnostic d'obstruction extrinsèque et incomplète du 3ème duodénum par la pince aorto-mésentérique. Une dérivation interne par duodéno-jéjunostomie sur anse en oméga a permis de contourner l'obstacle vasculaire avec des suites simples. Le TOGD de contrôle du 9ème jour postopératoire a montré une bonne perméabilité de l'anastomose duodéno-jéjunale. Les vomissements ont disparu et on note un gain pondéral de 2 kg en 3 mois. Les vomissements chroniques chez le nourrisson sont d’étiologies variées. L'obstacle siégeant au 3ème duodénum est le plus souvent dû à une pince aorto-mésentérique. Malheureusement ce diagnostic est rarement porté surtout en Afrique probablement du fait de l'insuffisance des moyens diagnostiques en particulier dans les zones reculées. Le traitement peut être fait par les moyens chirurgicaux ou nutritionnels. PMID:25767670

  12. Hendra virus

    PubMed Central

    Middleton, Deborah

    2014-01-01

    Synopsis Hendra virus infection of horses occurred sporadically between 1994 and 2010 as a result of spill-over from the viral reservoir in Australian mainland flying-foxes, and occasional onward transmission to people also followed from exposure to affected horses. For reasons that are not well understood an unprecedented number of outbreaks were recorded in 2011, including the first recorded field infection of a dog, leading to heightened community concern. Increasingly, pressure mounted to instigate measures for control of flying-fox numbers, and equine health care workers started to leave the industry on account of risk and liability concerns. Release of an inactivated subunit vaccine for horses against Hendra virus represents the first commercially available product that is focused on mitigating the impact of a Biosafety Level 4 pathogen. Through preventing the development of acute Hendra virus disease in horses, vaccine use is also expected to reduce the risk of transmission of infection to people. This approach to emerging infectious disease management focuses on the role of horses as the proximal cause of human Hendra virus disease, and may assist in redirecting community concerns away from the flying-fox reservoirs, keystone species for the ongoing health of Australia’s native forests. PMID:25281398

  13. Transforming properties of the cottontail rabbit papillomavirus oncoproteins Le6 and SE6 and of the E8 protein.

    PubMed Central

    Harry, J B; Wettstein, F O

    1996-01-01

    Cottontail rabbit papillomavirus induces on cottontail and domestic rabbits papillomas which progress at a high frequency to carcinoma. The virus encodes three transforming proteins; one is translated from open reading frame (ORF) E7 and binds the retinoblastoma protein, and two, LE6 and SE6, are translated from the first and second ATGs of ORF E6, respectively. Here we show that neither of the E6 proteins coprecipitated with p53 in vitro, nor did they bind to a recently identified E6-binding protein (J. J. Chen, C. E. Reid, V. Band, and E. Androphy, Science 269:529-531, 1995). This protein was shown to bind to the E6 proteins of the high-risk human papillomairus types 16 and 18 but not to the low-risk human papillomavirus types VI and II. In-frame deletions cloned into the pZipNeo vector were used to identify structural features of SE6 and LE6 important for transformation of NIH 3T3 cells. Three deletions covering the amino-terminal half of SE6 did not transform cells. In two of the three deletions, two Cys-X-X-Cys motifs were deleted, each deletion preventing the formation of one of the potential small Zn fingers of SE6. Among the LE6 deletions, only one had a reduced transformation efficiency, while seven transformed cells at least as efficiently as wild-type LE6. In each of three of these seven mutants, two Cys-X-X-Cys motifs were deleted. None of the three amino acid deletions which abolished transformation by SE6 reduced transformation by LE6. Furthermore, transformation did not correlate with the level of SE6 or LE6 proteins detectable. ORF E8 colinear with ORF E6, which could generate a 50-amino-acid protein with a hydrophobic segment, did not transform cells when cloned into the pZipNeo vector. However, mutation of the E8 ATG, which did not alter the amino acid sequence of LE6, increased transformation by LE6 without affecting the level of LE6 expression. The data suggest that transformation by the E6 proteins is not mediated by interfering with p53

  14. [Influenza virus].

    PubMed

    Juozapaitis, Mindaugas; Antoniukas, Linas

    2007-01-01

    Every year, especially during the cold season, many people catch an acute respiratory disease, namely flu. It is easy to catch this disease; therefore, it spreads very rapidly and often becomes an epidemic or a global pandemic. Airway inflammation and other body ailments, which form in a very short period, torment the patient several weeks. After that, the symptoms of the disease usually disappear as quickly as they emerged. The great epidemics of flu have rather unique characteristics; therefore, it is possible to identify descriptions of such epidemics in historic sources. Already in the 4th century bc, Hippocrates himself wrote about one of them. It is known now that flu epidemics emerge rather frequently, but there are no regular intervals between those events. The epidemics can differ in their consequences, but usually they cause an increased mortality of elderly people. The great flu epidemics of the last century took millions of human lives. In 1918-19, during "The Spanish" pandemic of flu, there were around 40-50 millions of deaths all over the world; "Pandemic of Asia" in 1957 took up to one million lives, etc. Influenza virus can cause various disorders of the respiratory system: from mild inflammations of upper airways to acute pneumonia that finally results in the patient's death. Scientist Richard E. Shope, who investigated swine flu in 1920, had a suspicion that the cause of this disease might be a virus. Already in 1933, scientists from the National Institute for Medical Research in London - Wilson Smith, Sir Christopher Andrewes, and Sir Patrick Laidlaw - for the first time isolated the virus, which caused human flu. Then scientific community started the exhaustive research of influenza virus, and the great interest in this virus and its unique features is still active even today. PMID:18182834

  15. Virus-induced gene complementation reveals a transcription factor network in modulation of tomato fruit ripening

    PubMed Central

    Zhou, Tao; Zhang, Hang; Lai, Tongfei; Qin, Cheng; Shi, Nongnong; Wang, Huizhong; Jin, Mingfei; Zhong, Silin; Fan, Zaifeng; Liu, Yule; Wu, Zirong; Jackson, Stephen; Giovannoni, James J.; Rolin, Dominique; Gallusci, Philippe; Hong, Yiguo

    2012-01-01

    Plant virus technology, in particular virus-induced gene silencing, is a widely used reverse- and forward-genetics tool in plant functional genomics. However the potential of virus technology to express genes to induce phenotypes or to complement mutants in order to understand the function of plant genes is not well documented. Here we exploit Potato virus X as a tool for virus-induced gene complementation (VIGC). Using VIGC in tomato, we demonstrated that ectopic viral expression of LeMADS-RIN, which encodes a MADS-box transcription factor (TF), resulted in functional complementation of the non-ripening rin mutant phenotype and caused fruits to ripen. Comparative gene expression analysis indicated that LeMADS-RIN up-regulated expression of the SBP-box (SQUAMOSA promoter binding protein-like) gene LeSPL-CNR, but down-regulated the expression of LeHB-1, an HD-Zip homeobox TF gene. Our data support the hypothesis that a transcriptional network may exist among key TFs in the modulation of fruit ripening in tomato. PMID:23150786

  16. Entrevue avec le Dr Charley Zeanah

    PubMed Central

    2013-01-01

    Le Dr Charles Zeanah est titulaire de la chaire de psychiatrie Mary K. Sellars-Polchow, professeur de pédiatrie clinique et vice-président de la pédopsychiatrie au département de psychiatrie et des sciences du comportement de la faculté de médecine de l’Université Tulane, à la Nouvelle-Orléans. Il est également directeur général de l’institut de la santé mentale des nourrissons et des jeunes enfants de Tulane. Il est récipiendaire de nombreux prix, notamment le prix de prévention Irving Phillips (AACAP), la mention élogieuse présidentielle pour sa recherche et son leadership exceptionnels en santé mentale des nourrissons (American Orthopsychiatric Association), le prix d’excellence clinique Sarah Haley Memorial (International Society for Traumatic Stress Studies), le prix de recherche en pédopsychiatrie Blanche F. Ittelson (APA), et le prix Serge Lebovici Award soulignant les contributions internationales à la santé mentale des nourrissons (World Association for Infant Mental Health). Le Dr Zeanah est fellow distingué de l’AACAP, fellow distingué de l’APA et membre du conseil d’administration de Zero to Three. Il est l’éditeur scientifique de Handbook of Infant Mental Health (3e édition) qui est considéré comme étant le manuel de pointe et la référence de base du domaine de la santé mentale des nourrissons.

  17. The Geometry of Viruses.

    ERIC Educational Resources Information Center

    Case, Christine L.

    1991-01-01

    Presented is an activity in which students make models of viruses, which allows them to visualize the shape of these microorganisms. Included are some background on viruses, the biology and geometry of viruses, directions for building viruses, a comparison of cells and viruses, and questions for students. (KR)

  18. Plant Virus Metagenomics: Advances in Virus Discovery.

    PubMed

    Roossinck, Marilyn J; Martin, Darren P; Roumagnac, Philippe

    2015-06-01

    In recent years plant viruses have been detected from many environments, including domestic and wild plants and interfaces between these systems-aquatic sources, feces of various animals, and insects. A variety of methods have been employed to study plant virus biodiversity, including enrichment for virus-like particles or virus-specific RNA or DNA, or the extraction of total nucleic acids, followed by next-generation deep sequencing and bioinformatic analyses. All of the methods have some shortcomings, but taken together these studies reveal our surprising lack of knowledge about plant viruses and point to the need for more comprehensive studies. In addition, many new viruses have been discovered, with most virus infections in wild plants appearing asymptomatic, suggesting that virus disease may be a byproduct of domestication. For plant pathologists these studies are providing useful tools to detect viruses, and perhaps to predict future problems that could threaten cultivated plants. PMID:26056847

  19. Measles virus

    PubMed Central

    Naim, Hussein Y

    2014-01-01

    Measles was an inevitable infection during the human development with substantial degree of morbidity and mortality. The severity of measles virus (MV) infection was largely contained by the development of a live attenuated vaccine that was introduced into the vaccination programs. However, all efforts to eradicate the disease failed and continued to annually result in significant deaths. The development of molecular biology techniques allowed the rescue of MV from cDNA that enabled important insights into a variety of aspects of the biology of the virus and its pathogenesis. Subsequently these technologies facilitated the development of novel vaccine candidates that induce immunity against measles and other pathogens. Based on the promising prospective, the use of MV as a recombinant vaccine and a therapeutic vector is addressed. PMID:25483511

  20. Urétéroscopie souple laser dans le traitement des calculs du haut appareil urinaire: résultats a propos de 166 interventions

    PubMed Central

    Padja, Essodina; Ibarra, Venceslas Amboulou; Lmezguidi, Khalid; Janane, Abdellatif; Ghadouane, Mohamed; Ameur, Ahmed; Abbar, Mohamed

    2015-01-01

    L’évolution de la technique opératoire fait de l'urétéroscopie souple –Laser (URSS-L) une méthode efficace et sure dans le traitement des calculs du haut appareil urinaire (HAU). Elle apparait comme une option salvatrice après échec des autres options thérapeutiques. Son coût limite son accessibilité et restreint ses indications dans certains contextes socio-économiques. Nous rapportons l'expérience du service sur les indications, les résultats et les complications de l'URSS-L dans le traitement des calculs du HAU. C'est une étude rétrospective sur 4ans concernant 130 patients ayant des calculs du HAU. Un scanner permettait de déterminer les caractéristiques des calculs avant l'intervention et de faire un contrôle après afin de juger de l'efficacité du traitement. Une analyse statistique évaluait l'influence des différents paramètres des calculs sur l'efficacité de l'intervention. Un suivi était réalisé afin de détecter les complications. L’âge moyen des patients était de 52 ± 17ans. 166 interventions étaient faites en 3 séries. Les indications étaient de première intention dans 50.32% suivi des échecs de LEC. La durée moyenne de l'intervention était de 73min ± 25min pour une taille moyenne des calculs de 13.78mm ± 5mm. Le taux de succès global était de 78.91% (78.71%; 80%; 100%) respectivement après la 1ère, la 2ème et la 3ème série. Aucun paramètre n'influençait significativement le taux de succès. 14.45% de complications était enregistré. L'URSS-L est une méthode aussi efficace que sure dans le traitement des calculs du HAU nous motivant malgré son coût, à élargir ses indications en première intention lorsque les calculs répondent aux critères de choix. PMID:26600912

  1. Infection par le VIH chez les patientes atteintes de cancer du sein en Guinée (Afrique de l'Ouest)

    PubMed Central

    Traore, Bangaly; Diane, Solomana; Sow, Mamadou Saliou; Keita, Mamady; Conde, Mamoudou; Traore, Fodé Amara; Kourouma, Tidiane

    2015-01-01

    L'objectif était de déterminer la prévalence de l'infection à VIH chez les patientes atteintes de cancer du sein et de comparer les caractéristiques anatomocliques et thérapeutiques de ces cancers du sein par rapports aux patientes non infectées par le VIH. Il s'agissait d'une étude rétrospective et analytique comparant les dossiers de patientes atteintes de cancers du sein histologiquement confirmés, infectées ou non par le VIH à l'unité de chirurgie oncologique de Donka, CHU de Conakry, de 2007 à 2012. Nous avons colligé 278 patientes présentant un cancer du sein dont 14 (5,0%) infectées par le VIH et 264 (95,0%) non infectées par le VIH. Les différences observées entre ces deux groupes de patientes étaient respectivement: âge médian (36,8 vs 49,0 ans), la ménopause (21,4% vs 53,4%), le nombre des patientes traitées (50,0% contre 77,1%) et la survenue de décès (78,6% vs 50,8%). Aucune différence n'a été notée dans la présentation clinique, histologique et le retard de consultation. Dans notre étude, la prévalence de l'infection à VIH chez les patients atteints de cancer du sein est élevée. L’âge jeune des patients, la faible accessibilité au traitement et la mortalité élevée doivent être confirmés par une étude sur un échantillon plus large. PMID:26523196

  2. Zika Virus.

    PubMed

    Musso, Didier; Gubler, Duane J

    2016-07-01

    Zika virus (ZIKV) is an arthropod-borne virus (arbovirus) in the genus Flavivirus and the family Flaviviridae. ZIKV was first isolated from a nonhuman primate in 1947 and from mosquitoes in 1948 in Africa, and ZIKV infections in humans were sporadic for half a century before emerging in the Pacific and the Americas. ZIKV is usually transmitted by the bite of infected mosquitoes. The clinical presentation of Zika fever is nonspecific and can be misdiagnosed as other infectious diseases, especially those due to arboviruses such as dengue and chikungunya. ZIKV infection was associated with only mild illness prior to the large French Polynesian outbreak in 2013 and 2014, when severe neurological complications were reported, and the emergence in Brazil of a dramatic increase in severe congenital malformations (microcephaly) suspected to be associated with ZIKV. Laboratory diagnosis of Zika fever relies on virus isolation or detection of ZIKV-specific RNA. Serological diagnosis is complicated by cross-reactivity among members of the Flavivirus genus. The adaptation of ZIKV to an urban cycle involving humans and domestic mosquito vectors in tropical areas where dengue is endemic suggests that the incidence of ZIKV infections may be underestimated. There is a high potential for ZIKV emergence in urban centers in the tropics that are infested with competent mosquito vectors such as Aedes aegypti and Aedes albopictus. PMID:27029595

  3. SAMPLING VIRUSES FROM SOIL

    EPA Science Inventory

    This chapter describes in detail methods for detecting viruses of bacteria and humans in soil. Methods also are presented for the assay of these viruses. Reference sources are provided for information on viruses of plants.

  4. Computer Viruses: An Overview.

    ERIC Educational Resources Information Center

    Marmion, Dan

    1990-01-01

    Discusses the early history and current proliferation of computer viruses that occur on Macintosh and DOS personal computers, mentions virus detection programs, and offers suggestions for how libraries can protect themselves and their users from damage by computer viruses. (LRW)

  5. Hanta virus (image)

    MedlinePlus

    Hanta virus is a distant cousin of Ebola virus, but is found worldwide. The virus is spread by human contact with rodent waste. Dangerous respiratory illness develops. Effective treatment is not yet ...

  6. Ebola Virus Disease

    MedlinePlus

    ... 2014 Fact sheets Features Commentaries 2014 Multimedia Contacts Ebola virus disease Fact sheet Updated January 2016 Key ... for survivors of Ebola virus disease Symptoms of Ebola virus disease The incubation period, that is, the ...

  7. L'astronomie dans le monde

    NASA Astrophysics Data System (ADS)

    Manfroid, J.

    2014-06-01

    Future lune ? - L'âge de la Lune - Des volcans actifs sur Vénus - Un lac dans le cratère Gusev ? - Météorites et atmosphère martiennes - L’hexagone de Saturne - Pluton - Exo-Terre - Bêta Pictoris b - Cérès et Vesta depuis Mars - Naine froide - Parallaxes par Hubble - L2 Puppis et le sort du Soleil - Supernova et lentille gravitationnelle - Champ magnétique galactique - L’objet de Sakurai - Fermi et la matière noire - Lentille naine

  8. Virus Movement Maintains Local Virus Population Diversity

    SciTech Connect

    J. Snyder; B. Wiedenheft; M. Lavin; F. Roberto; J. Spuhler; A. Ortmann; T. Douglas; M. Young

    2007-11-01

    Viruses are the largest reservoir of genetic material on the planet, yet little is known about the population dynamics of any virus within its natural environment. Over a 2-year period, we monitored the diversity of two archaeal viruses found in hot springs within Yellowstone National Park (YNP). Both temporal phylogeny and neutral biodiversity models reveal that virus diversity in these local environments is not being maintained by mutation but rather by high rates of immigration from a globally distributed metacommunity. These results indicate that geographically isolated hot springs are readily able to exchange viruses. The importance of virus movement is supported by the detection of virus particles in air samples collected over YNP hot springs and by their detection in metacommunity sequencing projects conducted in the Sargasso Sea. Rapid rates of virus movement are not expected to be unique to these archaeal viruses but rather a common feature among virus metacommunities. The finding that virus immigration rather than mutation can dominate community structure has significant implications for understanding virus circulation and the role that viruses play in ecology and evolution by providing a reservoir of mobile genetic material.

  9. Virus movement maintains local virus population diversity.

    PubMed

    Snyder, Jamie C; Wiedenheft, Blake; Lavin, Matthew; Roberto, Francisco F; Spuhler, Josh; Ortmann, Alice C; Douglas, Trevor; Young, Mark

    2007-11-27

    Viruses are the largest reservoir of genetic material on the planet, yet little is known about the population dynamics of any virus within its natural environment. Over a 2-year period, we monitored the diversity of two archaeal viruses found in hot springs within Yellowstone National Park (YNP). Both temporal phylogeny and neutral biodiversity models reveal that virus diversity in these local environments is not being maintained by mutation but rather by high rates of immigration from a globally distributed metacommunity. These results indicate that geographically isolated hot springs are readily able to exchange viruses. The importance of virus movement is supported by the detection of virus particles in air samples collected over YNP hot springs and by their detection in metacommunity sequencing projects conducted in the Sargasso Sea. Rapid rates of virus movement are not expected to be unique to these archaeal viruses but rather a common feature among virus metacommunities. The finding that virus immigration rather than mutation can dominate community structure has significant implications for understanding virus circulation and the role that viruses play in ecology and evolution by providing a reservoir of mobile genetic material. PMID:18025457

  10. 23. VIEW OF LE CLAIRE LOCK (19211925), SHOWING OPERATING MACHINERY, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    23. VIEW OF LE CLAIRE LOCK (1921-1925), SHOWING OPERATING MACHINERY, DOWSTREAM GATES, UPSTREAM SIDE - Mississippi River 9-Foot Channel, Lock & Dam No. 14, Upper Mississippi River, Le Claire, Scott County, IA

  11. 20. VIEW OF LE CLAIRE LOCK (19211925), SHOWING UPSTREAM GATES, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    20. VIEW OF LE CLAIRE LOCK (1921-1925), SHOWING UPSTREAM GATES, DOWNSTREAM SIDE AND SOUTH LOCKWALL - Mississippi River 9-Foot Channel, Lock & Dam No. 14, Upper Mississippi River, Le Claire, Scott County, IA

  12. 30. INTERIOR VIEW OF MISSISSIPPI RIVER RECREATION OFFICE, LE CLAIRE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    30. INTERIOR VIEW OF MISSISSIPPI RIVER RECREATION OFFICE, LE CLAIRE BASE COMPOUND, LOOKING EAST - Mississippi River 9-Foot Channel, Lock & Dam No. 14, Upper Mississippi River, Le Claire, Scott County, IA

  13. 29. INTERIOR VIEW OF MISSISSIPPI RIVER RECREATION OFFICE BUILDING, LE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    29. INTERIOR VIEW OF MISSISSIPPI RIVER RECREATION OFFICE BUILDING, LE CLAIRE BASE COMPOUND, LOOKING WEST - Mississippi River 9-Foot Channel, Lock & Dam No. 14, Upper Mississippi River, Le Claire, Scott County, IA

  14. Viruses and Virus Diseases of Rubus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rubus species are propagated vegetatively and are subject to infection by viruses during development, propagation and fruit production stages. Reports of initial detection and symptoms of more than 30 viruses, virus-like diseases and phytoplasmas affecting Rubus spp. have been reviewed more than 20 ...

  15. Le Francais Courant: Part V, French.

    ERIC Educational Resources Information Center

    Dade County Public Schools, Miami, FL.

    Instructional objectives of the Dade County Public Schools Quinmester Program in French for use with "Le Francais Courant: Part 5" focus on the development of mastery of the basic numbering system and other grammatical structures. Structures include the formation of the present tense of the irregular verbs "vouloir,""pouvoir," and "venir,"…

  16. Le Francais Moderne: Part I, French.

    ERIC Educational Resources Information Center

    Dade County Public Schools, Miami, FL.

    Instructional objectives of the Dade County Public Schools Quinmester Program in French for use with "Le Francais Moderne: Part 1" focus on the development of vocabulary and mastery of grammatical structures. The formation of the passe compose with "avoir," object pronouns, the present tense of regular "-ir" verbs, and the irregular verbs…

  17. Le Chatelier's principle in replicator dynamics

    NASA Astrophysics Data System (ADS)

    Allahverdyan, Armen E.; Galstyan, Aram

    2011-10-01

    The Le Chatelier principle states that physical equilibria are not only stable, but they also resist external perturbations via short-time negative-feedback mechanisms: a perturbation induces processes tending to diminish its results. The principle has deep roots, e.g., in thermodynamics it is closely related to the second law and the positivity of the entropy production. Here we study the applicability of the Le Chatelier principle to evolutionary game theory, i.e., to perturbations of a Nash equilibrium within the replicator dynamics. We show that the principle can be reformulated as a majorization relation. This defines a stability notion that generalizes the concept of evolutionary stability. We determine criteria for a Nash equilibrium to satisfy the Le Chatelier principle and relate them to mutualistic interactions (game-theoretical anticoordination) showing in which sense mutualistic replicators can be more stable than (say) competing ones. There are globally stable Nash equilibria, where the Le Chatelier principle is violated even locally: in contrast to the thermodynamic equilibrium a Nash equilibrium can amplify small perturbations, though both types of equilibria satisfy the detailed balance condition.

  18. Restart function of the LE-5 engine

    NASA Astrophysics Data System (ADS)

    Hirata, Kunio; Koyari, Yukio; Yanagawa, Koji; Katsuta, Hideaki; Taniguchi, Hirofumi; Torii, Yoshihiro

    1993-10-01

    This report presents the restart function of the LE-5 (Liquid Engine-5). The development of a de/anti-ice system and a sufficient pump precooling system was key in establishing this function. To ensure high reliability, a contingency device was also adopted. The functions were proved through actual flights.

  19. A Colorful Demonstration of Le Chbtelier's Principle.

    ERIC Educational Resources Information Center

    Last, Arthur M.; Slade, Peter W.

    1997-01-01

    Le Chbtelier's Principle states that, when a system at equilibrium is subjected to stress, the system will respond in such a way as to minimize the effect of the stress. Describes a lecture demonstration that illustrates shifts in the position of equilibrium caused by a variety of factors. The equilibrium mixture contains iron (III) and…

  20. Developpement d'outils quantitatifs pour le suivi par imagerie TEP/TDM de la reponse a la chimiotherapie et de sa toxicite

    NASA Astrophysics Data System (ADS)

    Croteau, Etienne

    L'objectif de ce projet de doctorat est de developper des outils quantitatifs pour le suivi des traitements de chimiotherapie pour le cancer du sein et de leurs effets cardiotoxiques a l'aide de l'imagerie TEP dynamique. L'analyse cinetique en TEP dynamique permet l'evaluation de parametres biologiques in vivo. Cette analyse peut etre utilise pour caracteriser la reponse tumorale a la chimiotherapie et les effets secondaires nefastes qui peuvent en resulter. Le premier article de cette these decrit la mise au point des techniques d'analyse cinetique qui utilisent la fonction d'entree d'un radiotraceur derive de l'image dynamique. Des corrections de contamination radioactive externe (epanchement) et de l'effet de volume partiel ont ete necessaires pour standardiser l'analyse cinetique et la rendre quantitative. Le deuxieme article porte sur l'evaluation d'un nouveau radiotraceur myocardique. Le 11C-acetoacetate, un nouveau radiotraceur base sur un corps cetonique, a ete compare au 11C-acetate, couramment utilise en imagerie cardiaque TEP. L'utilisation de 3H-acetate et 14C-acetoacetate ont permis d'elucider la cinetique de ces traceurs depuis la fonction d'entree et la captation par les mitochondries cardiaques qui reflete la consommation en oxygene, jusqu'a la liberation de leurs principaux metabolites reciproques (3H20 et 14CO2). Le troisieme et dernier article de cette these presente l'integration d'un modele qui evalue la reserve cardiaque de perfusion et de consommation en oxygene. Un modele de cardiomyopathie a ete etabli a l'aide d'un agent chimiotherapeutique contre le cancer du sein, la doxorubicine, reconnu comme etant cardiotoxique. Un protocole de repos/effort a permis d'evaluer la capacite d'augmentation de perfusion et de consommation en oxygene par le coeur. La demonstration d'une reserve cardiaque reduite caracterise la cardiotoxicite. La derniere contribution de cette these porte sur la mise au point de methodes peu invasives pour mesurer la

  1. Type-1 chain histo-blood group antigens (Le(a), monosialosyl-Le(a), disialosyl-Le(a), Le(b), and H) in normal and malignant human endometrium.

    PubMed

    Ravn, V; Mandel, U; Svenstrup, B; Dabelsteen, E

    1994-01-01

    Type-1 chain histo-blood group antigens such as the Lewis (Le)a, monosialosyl-Le(a), Le(b) and H antigens show an increased expression in endometrial carcinomas. However, the possibility that these antigens are expressed under genetic or hormonal influence in endometrial carcinomas has not been considered. In the present study, the expression of type-1 chain carbohydrate antigens in normal and malignant endometrium was evaluated by immunohistochemistry and related to both genetic and hormonal factors. The glands of normal, non-secretory endometria expressed, in contrast with surface epithelial cells, Le(a), Le(b), disialosyl-Le(a), and H determinants infrequently. Adenomatous hyperplasias and endometrial carcinomas showed an increased expression of type-1 chain carbohydrates that was qualitatively influenced by the erythrocyte Lewis phenotype and the secretor status. Whereas Le(a+b-) non-secretors mainly accumulated Le(a) antigen, and only limited amounts of Le(b) antigen, Le(a-b+) secretors expressed H, Le(b) and Le(a) antigens. The expression of type-1 chain antigens showed no association with the serum-oestrogen level or to the hormone-receptor status. Thus the Lewis secretor status has a qualitative influence on the increased expression of type-1 chain antigens, which, however, seem to be unrelated to hormonal factors. Our findings suggest an increased activity of the Se-gene-defined or a closely related fucosyl-transferase in neoplastic endometrial epithelial cells. PMID:8032530

  2. Eléments traces dans le sérum des enfants malnutris et bien nourris vivants à Lubumbashi et Kawama dans un contexte d'un environnement de pollution minière

    PubMed Central

    Musimwa, Aimée Mudekereza; Kanteng, Gray Wakamb; Kitoko, Hermann Tamubango; Luboya, Oscar Numbi

    2016-01-01

    Introduction La place des éléments traces métalliques essentiels en nutrition humaine ne peut plus être ignorée. Les déficits d'apports, les carences secondaires souvent sous – estimées, et les carences iatrogènes font le lit de pathologies telles que les infections et autres. D'où leurs dosages ont une importance particulière pour en évaluer la gravité et faciliter une prise en charge précoce ou améliorer le régime alimentaire. Cette étude a eu pour objectif de déterminer le profil sanguin en éléments traces (cuivre, sélénium, zinc, fer, chrome, cobalt, etc) chez les enfants malnutris et biens nourris dans un milieu minier à Lubumbashi. Méthodes Trois cents onze cas ont été colligés, 182 malnutris et 129 biens nourris, dans une étude descriptive transversale, effectuée de juillet 2013 à décembre 2014. Pour lequel un échantillonnage exhaustif a été réalisé. Le dosage des métaux dans le sérum s'est fait à l’ ICP-OES (spectrométrie de masse à plasma gon induit) au laboratoire de l'Office Congolais de Contrôle de Lubumbashi. Résultats Les oligoéléments essentiels (cuivre, zinc, sélénium et fer) se retrouvent à des concentrations très basses chez les enfants malnutris comme chez les biens nourris. L'arsenic, le cadmium, le magnésium et le manganèse se présentent à des concentrations normales par rapport aux valeurs de références chez les enfants biens nourris. L'antimoine, le chrome, le plomb et le cobalt se retrouvent élevés chez les malnutris et biens nourris. Le nickel est normal chez les malnutris et les biens nourris. Le magnésium, manganèse se sont présentés à des taux très bas chez les enfants malnutris. Conclusion Les enfants malnutris et biens nourris présentent une malnutrition aux oligo-éléments essentiels associés aux éléments traces métalliques. Ce qui permet de supposer qu'une carence en micronutriments essentiel favorise l'absorption des métaux lourds. PMID:27583075

  3. Virophages or satellite viruses?

    PubMed

    Krupovic, Mart; Cvirkaite-Krupovic, Virginija

    2011-11-01

    It has been argued that the smaller viruses associated with giant DNA viruses are a new biological entity. However, Mart Krupovic and Virginija Cvirkaite-Krupovic argue here that these smaller viruses should be classified with the satellite viruses. PMID:22016897

  4. The Tobacco Mosaic Virus.

    ERIC Educational Resources Information Center

    Sulzinski, Michael A.

    1992-01-01

    Explains how the tobacco mosaic virus can be used to study virology. Presents facts about the virus, procedures to handle the virus in the laboratory, and four laboratory exercises involving the viruses' survival under inactivating conditions, dilution end point, filterability, and microscopy. (MDH)

  5. Les perceptions des femmes tunisiennes selon le modèle des croyances liées à la santé et leurs pratiques relativement à l'ostéoporose

    PubMed Central

    Belgacem, Amina; Nouira, Amel; Soussi, Sonia

    2016-01-01

    Introduction L'étude a pour objectif de décrire les croyances des femmes et leurs pratiques liées à la santé et à l'ostéoporose, afin d'élaborer des interventions efficaces et ciblées pour la prévention de cette maladie dans le contexte tunisien. Méthodes Une étude descriptive transversale a été effectuée auprès de 100 femmes tunisiennes, âgées de 45 ans et plus, qui consultent au centre de santé de base d'une zone périurbaine de la région de Sousse (Tunisie). La collecte de l'information a été réalisée à l'aide de « l'échelle des croyances relatives à la santé sur l'ostéoporose» développée par Kim et ses collègues traduit en arabe et validé en Tunisie et le questionnaire de «Calcul des apports calciques quotidiens» développé par Fardellone Patrice. L'interprétation des résultants s'est basée sur le «Health Belief Model ». Résultats La perception des participantes pourrait être considérée comme au dessus de la moyenne pour la vulnérabilité de l'ostéoporose (58%), la gravité de la maladie, les avantages de la pratique de l'activité physique, les avantages de l'apport en calcium et la motivation à la santé; par contre, elle pourrait être considérée comme modérée concernant les obstacles à la prévention. Cependant, les pratiques exposant au risque de la maladie sont relativement fréquentes et ceci essentiellement en rapport avec des facteurs socio-économiques et culturels. Conclusion Les programmes de promotion doivent viser la création d'un environnement physique et social favorable à l'adoption des comportements à moindre risque et viser l'éducation ciblée de la population. PMID:27217868

  6. New Strategies To Combat Long-Term Unemployment in Belgium, Denmark and the United Kingdom. Synthesis Report = Nouvelles strategies de lutte contre le chomage de longue duree en Belgigue, au Danemark, et au Royaume-Uni. Rapport de synthese.

    ERIC Educational Resources Information Center

    Geers, Frederik; And Others

    This synthesis report provides information to policy makers, practitioners, and researchers on the new strategies and measures adopted in Belgium, Denmark, and the United Kingdom to combat long-term unemployment. It begins with a summary of strategies and measures adopted in each of the three countries. Each country report highlights the following…

  7. L'Arenig Llanvirn du Haut Atlas occidental et central (Maroc). Environnements sédimentaires, paléogéographie et contrôle de la sédimentation

    NASA Astrophysics Data System (ADS)

    Chacrone, Choukri; Hamoumi, Naïma

    2005-09-01

    The sedimentological study of Arenig-Llanvirn successions of Aït Lahsen (western High Atlas), Tizi-n-Tichka and Imini (central High Atlas) allow us to recognise two independent epeiric seas. In the western High Atlas, the sedimentation occurred in a wave- and storm-influenced delta, alimented by a source situated at the present-day location of the Argana corridor, under the control of sea-level fluctuations and subsidence. In the central High Atlas, the sedimentation occurred in an influenced tide and episodic storm delta, alimented by sources situated at the present-day location of the Siroua and Ouzellagh Massifs under the control of sea-level fluctuations and tectonics. To cite this article: C. Chacrone, N. Hamoumi, C. R. Geoscience 337 (2005).

  8. Le domaine des co-infections et des maladies concomitantes du Réseau canadien pour les essais VIH des IRSC : lignes directrices canadiennes pour la prise en charge et le traitement de la co-infection par le VIH et l’hépatite C chez les adultes

    PubMed Central

    Hull, Mark; Giguère, Pierre; Klein, Marina; Shafran, Stephen; Tseng, Alice; Côté, Pierre; Poliquin, Marc; Cooper, Curtis

    2014-01-01

    HISTORIQUE : De 20 % à 30 % des Canadiens qui vivent avec le VIH sont co-infectés par le virus de l’hépatite C (VHC), lequel est responsable d’une morbidité et d’une mortalité importantes. La prise en charge du VIH et du VHC est plus complexe en raison de l’évolution accélérée de la maladie hépatique, du choix et des critères d’initiation de la thérapie antirétrovirale et du traitement anti-VHC, de la prise en charge de la santé mentale et des toxicomanies, des obstacles socioéconomiques et des interactions entre les nouvelles thérapies antivirales à action directe du VHC et les antirétroviraux OBJECTIF : Élaborer des normes nationales de prise en charge des adultes co-infectés par le VHC et le VIH dans le contexte canadien. MÉTHODOLOGIE : Le Réseau canadien pour les essais VIH des Instituts de recherche en santé du Canada a réuni un groupe d’experts possédant des compétences cliniques en co-infection par le VIH et le VHC pour réviser les publications à jour ainsi que les lignes directrices et les protocoles en place. Après une vaste sollicitation afin d’obtenir des points de vue, le groupe de travail a approuvé des recommandations consensuelles, qu’il a caractérisées au moyen d’une échelle de qualité des preuves fondée sur la classe (bienfaits par rapport aux préjudices) et sur la catégorie (degré de certitude). RÉSULTATS : Toutes les personnes co-infectées par le VIH et le VHC devraient subir une évaluation en vue de recevoir un traitement du VHC. Les personnes qui ne sont pas en mesure d’entreprendre un traitement du VHC devraient être soignées pour le VIH afin de ralentir l’évolution de la maladie hépatique. La norme de traitement du VHC de génotype 1 est un régime comprenant de l’interféron pégylé et de la ribavirine dosée en fonction du poids, associés à un inhibiteur de la protéase du VHC. Pour les génotypes 2 ou 3, une bithérapie classique est recommandée pendant 24 semaines s

  9. Le syndrome d’alcoolisme foetal

    PubMed Central

    2002-01-01

    L’alcool est un tératogène physique et comportemental. Le syndrome d’alcoolisme foetal (SAF) est un trouble courant mais encore sous-diagnostiqué découlant de la consommation d’alcool par la mère pendant la grossesse. Bien qu’il puisse être prévenu, le SAF est également invalidant. Même si le SAF est présent dans tous les groupes socioéconomiques du Canada, sa prévalence est élevée dans certaines communautés inuites et des Premières nations du Canada. Le présent énoncé porte sur la prévention, le diagnostic, le dépistage précoce et la prise en charge du SAF par les professionnels de la santé. La prévention du SAF doit s’effectuer à deux échelons. La prévention primaire consiste à éliminer le SAF par une formation en classe ou dans la collectivité et à inciter les femmes à éviter de consommer de l’alcool avant la conception et pendant la grossesse. La prévention secondaire consiste à repérer les femmes qui boivent pendant leur grossesse et à réduire leur consommation. Le présent énoncé décrit plusieurs stratégies de dépistage, dont la stratégie T-ACE (tolérance-agacement, réduction, éveil). Les dispensateurs de soins devraient recommander l’abstinence dès la première visite prénatale. Un envoi rapide en consultation en vue de traiter l’alcoolisme est recommandé pour les femmes enceintes incapables d’arrêter de boire. Le présent énoncé décrit le diagnostic de SAF, de SAF partiel ou atypique, d’anomalies congénitales et de troubles neurodéveloppementaux reliés à l’alcool. En cas d’exposition à l’alcool in utero, un diagnostic de SAF devrait être envisagé en présence d’un retard de croissance courant ou antérieur, de certaines anomalies faciales touchant la lèvre supérieure et les yeux et d’anomalies neurodéveloppementales. Ces caractéristiques sont mieux quantifiées au moyen d’une méthode diagnostique à quatre chiffres. Des stratégies de dépistage précoce des

  10. Tuberculose chez le personnel de santé du secteur public au Burundi: fréquence et facteurs de risque

    PubMed Central

    Mukuku, Olivier; Ruhindiza, Bienvenu Mukuku; Mupepe, Alexis Kumba; Sawadogo, Michel

    2013-01-01

    Introduction Le but de cette étude était de déterminer la fréquence de la tuberculose (TB) chez le personnel de santé du secteur public en charge des patients tuberculeux et d’évaluer les facteurs de risque de contracter la tuberculose chez ce personnel au Burundi. Méthodes Il s’agit d’une étude transversale à visée analytique réalisée auprès de 300 travailleurs prestant dans 30 centres de dépistage et de traitement de la TB (CDT) au Burundi du 16 octobre au 15 novembre 2012. Les paramètres sociodémographiques et professionnels ainsi que l’antécédent de vaccination BCG de travailleurs ayant été touché par la TB ont été analysé et comparé à ceux de travailleurs qui ne l’ont pas été. Le seuil de signification a été fixé à p < 0,05. Résultats La fréquence de la TB chez le personnel de santé est de 15%. Le risque de souffrir de la TB est de près de 4 fois chez les travailleurs âgés d’au moins 50 ans (OR=3,73; 1,53-9,08), chez ceux qui n’ont jamais reçu de vaccin de BCG (OR=3,73; 1,24-11,03), chez ceux qui n’ont pas de cicatrice vaccinale de BCG (OR=3,80; 1,67-8,62) et chez ceux qui travaillent depuis au moins 6 ans dans un CDT (OR=3,79; 1,44-9,96); ce risque est de 9 fois chez ceux qui sont mariés (OR=9,42; 1,26-70,23), de 8 fois chez ceux qui n’aèrent pas leurs salles de travail (OR=8,20; 1,48-48,23) et de 6 fois chez ceux qui ont comme profession nettoyeur ou aide-soignant (OR=6,12; 2,92-12,82). Par contre, aucune corrélation statistiquement significative n’a été observée entre le fait de souffrir de la TB et le sexe mais aussi le nombre d’heures de contact d’un travailleur avec un patient tuberculeux (p>0,05). Conclusion L’âge, l’antécédent de vaccination de BCG ainsi que la majorité de paramètres professionnels sont en association avec la maladie TB des travailleurs de CDT. D’où, la maîtrise de certains facteurs de risque s’avère important pour faire face au fardeau de la TB parmi

  11. Virus-Vectored Influenza Virus Vaccines

    PubMed Central

    Tripp, Ralph A.; Tompkins, S. Mark

    2014-01-01

    Despite the availability of an inactivated vaccine that has been licensed for >50 years, the influenza virus continues to cause morbidity and mortality worldwide. Constant evolution of circulating influenza virus strains and the emergence of new strains diminishes the effectiveness of annual vaccines that rely on a match with circulating influenza strains. Thus, there is a continued need for new, efficacious vaccines conferring cross-clade protection to avoid the need for biannual reformulation of seasonal influenza vaccines. Recombinant virus-vectored vaccines are an appealing alternative to classical inactivated vaccines because virus vectors enable native expression of influenza antigens, even from virulent influenza viruses, while expressed in the context of the vector that can improve immunogenicity. In addition, a vectored vaccine often enables delivery of the vaccine to sites of inductive immunity such as the respiratory tract enabling protection from influenza virus infection. Moreover, the ability to readily manipulate virus vectors to produce novel influenza vaccines may provide the quickest path toward a universal vaccine protecting against all influenza viruses. This review will discuss experimental virus-vectored vaccines for use in humans, comparing them to licensed vaccines and the hurdles faced for licensure of these next-generation influenza virus vaccines. PMID:25105278

  12. L'astronomie dans le monde

    NASA Astrophysics Data System (ADS)

    Manfroid, J.

    2013-06-01

    Une binaire remarquable; Collision de galaxies; La nébuleuse planétaire C1295; ALMA (suite); Couple massif; Astéroïdes lointains; L’eau de Jupiter; Occultation par Pluton; Super-Terres; Première image d’une planète massive autour d’une étoile double; Tempête au pôle de Saturne

  13. Viruses Infecting Reptiles

    PubMed Central

    Marschang, Rachel E.

    2011-01-01

    A large number of viruses have been described in many different reptiles. These viruses include arboviruses that primarily infect mammals or birds as well as viruses that are specific for reptiles. Interest in arboviruses infecting reptiles has mainly focused on the role reptiles may play in the epidemiology of these viruses, especially over winter. Interest in reptile specific viruses has concentrated on both their importance for reptile medicine as well as virus taxonomy and evolution. The impact of many viral infections on reptile health is not known. Koch’s postulates have only been fulfilled for a limited number of reptilian viruses. As diagnostic testing becomes more sensitive, multiple infections with various viruses and other infectious agents are also being detected. In most cases the interactions between these different agents are not known. This review provides an update on viruses described in reptiles, the animal species in which they have been detected, and what is known about their taxonomic positions. PMID:22163336

  14. Les Troubles Respiratoires Chez Le Brule

    PubMed Central

    Fassi Fihri, J.; Ezzoubi, M.; Boukind, E.H.

    2010-01-01

    Summary A travers une revue de la littérature, cet article se propose d'exposer les particularités des troubles respiratoires chez le brûlé. Ces troubles sont liés à un mécanisme direct, lorsque l'arbre respiratoire est lésé par le transfert d'énergie thermique du à la brûlure et/ou par un mécanisme indirect, lorsque la fonction respiratoire et ventilatoire du poumon est perturbée par les phénomènes loco-régionaux ou généraux du brûlé. Ces troubles respiratoires sont aggravés par l'inhalation des gaz contenus dans la fumée d'incendie. Le diagnostic de ces troubles est clinique et paraclinique. Il doit être précoce et continu. Les patients nécessitent de différents moyens thérapeutiques tels que l'oxygénothérapie, la libération des voies respiratoires, l'amélioration de la mécanique ventilatoire et de la fonction respiratoire, l'antibiothérapie ou la chirurgie des séquelles. Cette prise en charge doit nécessairement être multidisciplinaire. PMID:21991224

  15. Factors associated with mortality in human immunodeficiency virus type 1-infected adults initiating protease inhibitor-containing therapy: role of education level and of early transaminase level elevation (APROCO-ANRS EP11 study). The Antiprotéases Cohorte Agence Nationale de Recherches sur le SIDA EP 11 study.

    PubMed

    Lewden, Charlotte; Raffi, François; Cuzin, Lise; Cailleton, Valérie; Vildé, Jean-Louis; Chêne, Geneviève; Allavena, Clotilde; Salamon, Roger; Leport, Catherine

    2002-09-01

    This study attempted to identify factors associated with mortality among human immunodeficiency virus (HIV)-infected adults starting a protease inhibitor (PI)-containing therapy. Among 1155 patients consecutively enrolled in the APROCO study between May 1997 and June 1998, clinical characteristics were as follows: median age, 36 years; median baseline CD4 cell count, 288 cells/mm(3); and median baseline plasma HIV RNA load, 4.4 log(10) copies/mL. After a median follow-up of 27 months, 48 deaths had occurred, of which 44% were related to acquired immune deficiency syndrome. The mortality rate was 2.9% at 12 months. When both data at baseline and data at 4 months after the start of PI therapy were considered, factors independently associated with mortality were (Cox model) low baseline plasma creatinine level, low school education level, low CD4 cell count at 4 months, low hemoglobin level, and elevated hepatic transaminase levels. Thus, social context plus clinical and biologic data, including the 4-month response to treatment, must be considered in treatment of HIV-infected patients. PMID:12195361

  16. Morphogenesis of Bittner Virus

    PubMed Central

    Gay, Frederick W.; Clarke, John K.; Dermott, Evelyn

    1970-01-01

    The morphogenesis of Bittner virus (mouse mammary tumor virus) was studied in sectioned mammary tumor cells. Internal components of the virus (type A particles) were seen being assembled in virus factories close to the nucleus and were also seen forming at the plasma membrane. The particles in virus factories became enveloped by budding through the membrane of cytoplasmic vacuoles which were derived from dilated endoplasmic reticulum. Complete virus particles were liberated from these vacuoles by cell lysis. Particles budding at the plasma membrane were released into intercellular spaces. Maturation of enveloped virus occurred after release, but mature internal components were rarely seen in the cytoplasm before envelopment. Direct cell-to-cell transfer of virus by pinocytosis of budding particles by an adjacent cell was observed, and unusual forms of budding virus which participated in this process are illustrated and described. There was evidence that some virus particles contained cytoplasmic constituents, including ribosomes. Certain features of the structure of internal components are discussed in relation to a recently proposed model for the internal component of the mouse leukemia virus. Intracisternal virus-like particles were occasionally seen in tumor cells, but there was no evidence that these structures were developmentally related to Bittner virus. Images PMID:4193837

  17. Raspberry (Rubus spp.)-Viruses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    There are several important virus diseases of raspberry and black raspberry in the Pacific Northwest. Pollen-borne viruses include Raspberry bushy dwarf virus and Strawberry necrotic shock virus (aka Tobacco streak virus –Rubus isolate or Black raspberry latent virus). Strawberry necrotic shock viru...

  18. Tumorigenic DNA viruses

    SciTech Connect

    Klein, G.

    1989-01-01

    The eighth volume of Advances in Viral Oncology focuses on the three major DNA virus groups with a postulated or proven tumorigenic potential: papillomaviruses, animal hepatitis viruses, and the Epstein-Bar virus. In the opening chapters, the contributors analyze the evidence that papillomaviruses and animal hepatitis viruses are involved in tumorigenesis and describe the mechanisms that trigger virus-host cell interactions. A detailed section on the Epstein-Barr virus (EBV) - comprising more than half the book - examines the transcription and mRNA processing patterns of the virus genome; the mechanisms by which EBV infects lymphoid and epithelial cells; the immunological aspects of the virus; the actions of EBV in hosts with Acquired Immune Deficiency Syndrome; and the involvement of EBV in the etiology of Burkitt's lymphoma.

  19. Zika Virus Fact Sheet

    MedlinePlus

    ... 2014 Fact sheets Features Commentaries 2014 Multimedia Contacts Zika virus Fact sheet Updated 6 September 2016 Key facts ... and last for 2-7 days. Complications of Zika virus disease After a comprehensive review of evidence, there ...

  20. Viruses and Breast Cancer

    PubMed Central

    Lawson, James S.; Heng, Benjamin

    2010-01-01

    Viruses are the accepted cause of many important cancers including cancers of the cervix and anogenital area, the liver, some lymphomas, head and neck cancers and indirectly human immunodeficiency virus associated cancers. For over 50 years, there have been serious attempts to identify viruses which may have a role in breast cancer. Despite these efforts, the establishment of conclusive evidence for such a role has been elusive. However, the development of extremely sophisticated new experimental techniques has allowed the recent development of evidence that human papilloma virus, Epstein-Barr virus, mouse mammary tumor virus and bovine leukemia virus may each have a role in the causation of human breast cancers. This is potentially good news as effective vaccines are already available to prevent infections from carcinogenic strains of human papilloma virus, which causes cancer of the uterine cervix. PMID:24281093

  1. Respiratory Syncytial Virus Infections

    MedlinePlus

    Respiratory syncytial virus (RSV) causes mild, cold-like symptoms in adults and older healthy children. It can cause serious problems in ... tests can tell if your child has the virus. There is no specific treatment. You should give ...

  2. Human Parainfluenza Viruses

    MedlinePlus

    ... HPIVs Are Not the Same as Influenza (Flu) Viruses People usually get HPIV infections more often in ... hands, and touching objects or surfaces with the viruses on them then touching your mouth, nose, or ...

  3. Advances in virus research

    SciTech Connect

    Maramorosch, K. ); Murphy, F.A. ); Shatkin, A.J. )

    1988-01-01

    This book contains eight chapters. Some of the titles are: Initiation of viral DNA replication; Vaccinia: virus, vector, vaccine; The pre-S region of hepadnavirus envelope proteins; and Archaebacterial viruses.

  4. Herpes Simplex Virus (HSV)

    MedlinePlus

    ... rashes clinical tools newsletter | contact Share | Herpes Simplex Virus (HSV) A parent's guide to condition and treatment ... skin or mouth sores with the herpes simplex virus (HSV) is called primary herpes. This may be ...

  5. Virus Assembly and Maturation

    NASA Astrophysics Data System (ADS)

    Johnson, John E.

    2004-03-01

    We use two techniques to look at three-dimensional virus structure: electron cryomicroscopy (cryoEM) and X-ray crystallography. Figure 1 is a gallery of virus particles whose structures Timothy Baker, one of my former colleagues at Purdue University, used cryoEM to determine. It illustrates the variety of sizes of icosahedral virus particles. The largest virus particle on this slide is the Herpes simplex virus, around 1200Å in diameter; the smallest we examined was around 250Å in diameter. Viruses bear their genomic information either as positive-sense DNA and RNA, double-strand DNA, double-strand RNA, or negative-strand RNA. Viruses utilize the various structure and function "tactics" seen throughout cell biology to replicate at high levels. Many of the biological principles that we consider general were in fact discovered in the context of viruses ...

  6. West Nile virus

    MedlinePlus

    West Nile virus is a disease spread by mosquitoes. The condition ranges from mild to severe. ... West Nile virus was first identified in 1937 in Uganda in eastern Africa. It was first discovered in the U.S. in ...

  7. Hepatitis D Virus Replication.

    PubMed

    Taylor, John M

    2015-11-01

    This work reviews specific related aspects of hepatitis delta virus (HDV) reproduction, including virion structure, the RNA genome, the mode of genome replication, the delta antigens, and the assembly of HDV using the envelope proteins of its helper virus, hepatitis B virus (HBV). These topics are considered with perspectives ranging from a history of discovery through to still-unsolved problems. HDV evolution, virus entry, and associated pathogenic potential and treatment of infections are considered in other articles in this collection. PMID:26525452

  8. Avian influenza virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Avian influenza virus (AIV) is type A influenza, which is adapted to an avian host. Although avian influenza has been isolated from numerous avian species, the primary natural hosts for the virus are dabbling ducks, shorebirds, and gulls. The virus can be found world-wide in these species and in o...

  9. Computer Virus Protection

    ERIC Educational Resources Information Center

    Rajala, Judith B.

    2004-01-01

    A computer virus is a program--a piece of executable code--that has the unique ability to replicate. Like biological viruses, computer viruses can spread quickly and are often difficult to eradicate. They can attach themselves to just about any type of file, and are spread by replicating and being sent from one individual to another. Simply having…

  10. Respiratory Syncytial Virus

    MedlinePlus

    ... Palsy: Shannon's Story" 5 Things to Know About Zika & Pregnancy Respiratory Syncytial Virus KidsHealth > For Parents > Respiratory Syncytial Virus Print A ... often get it when older kids carry the virus home from school and pass it to ... often happen in epidemics that last from late fall through early spring. ...

  11. BOVINE VIRAL DIARRHEA VIRUSES

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Bovine viral diarrhea virus (BVDV) is an umbrella term for two species of viruses, BVDV1 and BVDV2, within the Pestivirus genus of the Flavivirus family. BVDV viruses are further subclassified as cytopathic and noncytopathic based on their activity in cultured epithelial cells. Noncytopathic BVDV p...

  12. Le déficit immunitaire humoral: mieux le connaître pour mieux le prendre en charge

    PubMed Central

    El Bakkouri, Jalila; Aadam, Zahra; Ailal, Fatima; Alj, Hanane Salih; Bousfiha, Ahmed Aziz

    2014-01-01

    Les déficits immunitaires humoraux (DIH) sont des maladies hétérogènes allant des formes asymptomatiques rencontrés lors des déficits sélectifs en immunoglobulines A (IgA) et en sous-classes d'IgG aux formes graves des agammaglobulinémies congénitales. Les patients atteints de DIH présentent souvent des infections ORL ou des voies respiratoires récidivantes ou sévères. Ces patients peuvent présenter un certain nombre de complications non infectieuses, telles que des manifestations auto-immunes et des entéropathies, qui pourraient être le seul symptôme clinique révélateur. Les formes sévères des DIH sont facilement diagnostiquées grâce au dosage des IgG totaux, des IgA et des IgM. La thérapie substitutive par les immunoglobulines reste le traitement de choix chez ces patients. PMID:25489366

  13. The taxonomy of viruses should include viruses.

    PubMed

    Calisher, Charles H

    2016-05-01

    Having lost sight of its goal, the International Committee on Taxonomy of Viruses has redoubled its efforts. That goal is to arrive at a consensus regarding virus classification, i.e., proper placement of viruses in a hierarchical taxonomic scheme; not an easy task given the wide variety of recognized viruses. Rather than suggesting a continuation of the bureaucratic machinations of the past, this opinion piece is a call for insertion of common sense in sorting out the avalanche of information already, and soon-to-be, accrued data. In this way information about viruses ideally would be taxonomically correct as well as useful to working virologists and journal editors, rather than being lost, minimized, or ignored. PMID:26914357

  14. Blueberry (Vaccinium corymbosum)-Virus Diseases

    Technology Transfer Automated Retrieval System (TEKTRAN)

    At least six viruses have been found in highbush blueberry plantings in the Pacific Northwest: Blueberry mosaic virus, Blueberry red ringspot virus, Blueberry scorch virus, Blueberry shock virus, Tobacco ringspot virus, and Tomato ringspot virus. Six other virus and virus-like diseases of highbush b...

  15. Viruses of asparagus.

    PubMed

    Tomassoli, Laura; Tiberini, Antonio; Vetten, Heinrich-Josef

    2012-01-01

    The current knowledge on viruses infecting asparagus (Asparagus officinalis) is reviewed. Over half a century, nine virus species belonging to the genera Ilarvirus, Cucumovirus, Nepovirus, Tobamovirus, Potexvirus, and Potyvirus have been found in this crop. The potyvirus Asparagus virus 1 (AV1) and the ilarvirus Asparagus virus 2 (AV2) are widespread and negatively affect the economic life of asparagus crops reducing yield and increasing the susceptibility to biotic and abiotic stress. The main properties and epidemiology of AV1 and AV2 as well as diagnostic techniques for their detection and identification are described. Minor viruses and control are briefly outlined. PMID:22682173

  16. [Viruses as biological weapons].

    PubMed

    Akçali, Alper

    2005-07-01

    The destruction made by nuclear, biological and chemical weapons used by governments and terrorist groups in the near history is posing anxiety and fear for human being. Rumour about the possible use of these agents leads to the development of serious negative effects on populations. Since there are no vaccine and therapy for most viral agents and cost of production as biological weapons is low, interest rate is rising for viruses. In this review, general characteristics, diagnosis, therapy and protective measures for viral agents such as variola virus, hemorrhagic fever viruses, encephalitis viruses, Hantaviruses and Nipah viruses, those can be used as biological weapon, have been summarized. PMID:16358499

  17. Online identification of viruses.

    PubMed

    Kolaskar, A S; Naik, P S

    2000-06-01

    A computerized animal virus information system is developed in the Sequence Retrieval System (SRS) format. This database is available on the Word Wide Web (WWW) at the site http://bioinfo.ernet.in/www/avis/avis++ +.html. The database has been used to generate large number of identification matrices for each family. The software is developed in C. Unix shell scripts and Hypertext Marked-up Language (HTML) to assign the family to an unknown virus deterministically and to identify the virus probabilistically. It has been shown that such web based virus identification approach provides results with high confidence in those cases where identification matrix uses large number of independent characters. Protein sequence data for animal viruses have been analyzed and oligopeptides specific to each virus family and also specific to each virus species are identified for several viruses. These peptides thus could be used to identify the virus and to assign the virus family with high confidence showing the usefulness of sequence data in virus identification. PMID:10917875

  18. Serodiagnosis for Tumor Viruses

    PubMed Central

    Morrison, Brian J.; Labo, Nazzarena; Miley, Wendell J.; Whitby, Denise

    2015-01-01

    The known human tumor viruses include the DNA viruses Epstein-Barr virus, Kaposi sarcoma herpesvirus, Merkel cell polyomavirus, human papillomavirus, and hepatitis B virus. RNA tumor viruses include Human T-cell lymphotrophic virus type-1 and hepatitis C virus. The serological identification of antigens/antibodies in plasma serum is a rapidly progressing field with utility for both scientists and clinicians. Serology is useful for conducting seroepidemiology studies and to inform on the pathogenesis and host immune response to a particular viral agent. Clinically, serology is useful for diagnosing current or past infection and for aiding in clinical management decisions. Serology is useful for screening blood donations for infectious agents and for monitoring the outcome of vaccination against these viruses. Serodiagnosis of human tumor viruses has improved in recent years with increased specificity and sensitivity of the assays, as well as reductions in cost and the ability to assess multiple antibody/antigens in single assays. Serodiagnosis of tumor viruses plays an important role in our understanding of the prevalence and transmission of these viruses and ultimately in the ability to develop treatments/preventions for these globally important diseases. PMID:25843726

  19. Lipids of Archaeal Viruses

    PubMed Central

    Roine, Elina; Bamford, Dennis H.

    2012-01-01

    Archaeal viruses represent one of the least known territory of the viral universe and even less is known about their lipids. Based on the current knowledge, however, it seems that, as in other viruses, archaeal viral lipids are mostly incorporated into membranes that reside either as outer envelopes or membranes inside an icosahedral capsid. Mechanisms for the membrane acquisition seem to be similar to those of viruses infecting other host organisms. There are indications that also some proteins of archaeal viruses are lipid modified. Further studies on the characterization of lipids in archaeal viruses as well as on their role in virion assembly and infectivity require not only highly purified viral material but also, for example, constant evaluation of the adaptability of emerging technologies for their analysis. Biological membranes contain proteins and membranes of archaeal viruses are not an exception. Archaeal viruses as relatively simple systems can be used as excellent tools for studying the lipid protein interactions in archaeal membranes. PMID:23049284

  20. Connaissances, attitudes et pratiques de la population de l'aire de santé SAMBWA en rapport avec le traitement de l'onchocercose à l'ivermectine sous directives communautaires

    PubMed Central

    Philippe, Cilundika Mulenga; Bienvenu, Yogolelo Asani; Francoise, Malonga Kaj; Eric, Mukomena Sompwe; Abdon, Mukalay wa Mukalay; Luboya, Oscar Numbi

    2014-01-01

    Introduction L'onchocercose constitue un problème majeur de santé publique et l'on a noté environ 13 millions de personnes affectées et 26 millions exposées au cours de l'année 2012 en RDC. L'objectif de notre étude est fournir les données sur le niveau de connaissance, d'attitudes et des pratiques de la communauté huit ans après le lancement de la distribution de l'ivermectine sous directives communautaires. Méthodes Il s'agit d'une étude descriptive transversale dans la communauté de l'aire de santé SAMBWA de la zone de santé de KAFUBU. La population cible de l’étude est toute personne de la communauté âgée de 15 à 65 ans. Les paramètres étudiés sont: âge, niveau d'instruction, connaissance de la maladie en langue locale et des signes, attitudes devant les personnes atteintes, perception de la maladie, utilisation des pratiques traditionnelles, association entre le niveau d'instruction et la connaissance de savoir si l'on peut suivre un traitement. Résultats La moyenne d’âge des répondants était de 38±14 ans et 67,54% des enquêtés étaient de niveau primaire. L’étude a montré que 99,53% des répondants connaissaient le terme onchocercose en langue locale (UBUMFUKU) et un niveau moyen de connaissance en ce qui concerne les lésions de la peau (66,9%) était noté. 1,9% des répondants craignaient les personnes atteintes et 42,2% des répondants percevaient l'onchocercose comme une maladie. Une proportion de 55% qui prenaient les plantes comme médicament. Il y avait association significative entre le niveau d'instruction et la connaissance de suivre un traitement contre l'onchocercose (p: 0,008). Conclusion Ces résultats interpellent en ce qui concerne la sensibilisation de la communauté sur l'onchocercose. Les stratégies de lutte contre l'onchocercose devraient prendre en compte ces différentes insuffisances de la communauté pour améliorer le traitement des masses par l'ivermectine tant au niveau du ménage que des

  1. Intracranial subdural hygroma after Le Fort I osteotomy.

    PubMed

    Thompson, William L; Lee, Michael; MacIntosh, Robert Bruce

    2015-04-01

    Various intra- and postoperative complications have been well-documented after Le Fort I osteotomies; however, an intracranial subdural hygroma has not yet been reported in oral and maxillofacial studies. We report a unique case of an intracranial subdural hygroma requiring neurosurgical intervention after Le Fort I advancement. PMID:25631863

  2. RNA Viruses Infecting Pest Insects

    Technology Transfer Automated Retrieval System (TEKTRAN)

    RNA viruses are viruses whose genetic material is ribonucleic acid (RNA). RNA viruses may be double or single-stranded based on the type of RNA they contain. Single-stranded RNA viruses can be further grouped into negative sense or positive-sense viruses according to the polarity of their RNA. Fur...

  3. Postmortem stability of Ebola virus.

    PubMed

    Prescott, Joseph; Bushmaker, Trenton; Fischer, Robert; Miazgowicz, Kerri; Judson, Seth; Munster, Vincent J

    2015-05-01

    The ongoing Ebola virus outbreak in West Africa has highlighted questions regarding stability of the virus and detection of RNA from corpses. We used Ebola virus-infected macaques to model humans who died of Ebola virus disease. Viable virus was isolated <7 days posteuthanasia; viral RNA was detectable for 10 weeks. PMID:25897646

  4. Lifestyles of plant viruses

    PubMed Central

    Roossinck, Marilyn J.

    2010-01-01

    The vast majority of well-characterized eukaryotic viruses are those that cause acute or chronic infections in humans and domestic plants and animals. However, asymptomatic persistent viruses have been described in animals, and are thought to be sources for emerging acute viruses. Although not previously described in these terms, there are also many viruses of plants that maintain a persistent lifestyle. They have been largely ignored because they do not generally cause disease. The persistent viruses in plants belong to the family Partitiviridae or the genus Endornavirus. These groups also have members that infect fungi. Phylogenetic analysis of the partitivirus RNA-dependent RNA polymerase genes suggests that these viruses have been transmitted between plants and fungi. Additional families of viruses traditionally thought to be fungal viruses are also found frequently in plants, and may represent a similar scenario of persistent lifestyles, and some acute or chronic viruses of crop plants may maintain a persistent lifestyle in wild plants. Persistent, chronic and acute lifestyles of plant viruses are contrasted from both a functional and evolutionary perspective, and the potential role of these lifestyles in host evolution is discussed. PMID:20478885

  5. Systeme microfluidique d'analyse sanguine en temps reel pour l'imagerie moleculaire chez le petit animal

    NASA Astrophysics Data System (ADS)

    Convert, Laurence

    îtrise pour leur optimisation. En parallèle, les travaux ont été poursuivis avec des détecteurs du commerce sous forme de gaufres non découpées. Un premier dispositif intégrant des canaux en KMPR sur ces gaufres a permis de valider le concept démontrant le grand potentiel de ces choix technologiques et incitant à poursuivre les développements dans cette voie, notamment en envisageant des expériences animales. L'utilisation prolongée des canaux avec du sang non dilué est cependant particulièrement exigeante pour les matériaux artificiels. Une passivation à l'albumine a permis d'augmenter considérablement la compatibilité sanguine de la résine KMPR. Le concept initial, incluant la passivation des canaux, a ensuite été optimisé et intégré dans un système de mesure complet avec toute l'électronique et l'informatique de contrôle. Le système final a été validé chez le petit animal avec un radiotraceur connu. Ces travaux ont donné lieu à la première démonstration d'un détecteur microfluidique de haute efficacité pour la TEP et la TEM. Cette première brique d'un projet plus global est déjà un outil innovant en soi qui permettra d'augmenter l'efficacité du développement d'outils diagnostiques plus spécifiques principalement pour l'oncologie, la cardiologie et la neurologie. Mots clefs : imagerie moléculaire, tomographie d'émission par positrons (TEP), tomographie d'émission monophotonique (TEM), microfluidique, détecteur de radioactivité, KMPR, diodes p-i-n, hémocompatibilité.

  6. The Use of Le by L1 Chinese Speakers and the Acquisition of Le by L2 Chinese Learners

    ERIC Educational Resources Information Center

    Bredeche, Chi Chen

    2011-01-01

    The perfective marker V-"le" is claimed to be one of the most problematic items in the acquisition of L2 Chinese, perhaps because no unified and comprehensive treatment of it exists in the literature. Although much has been written on this topic, the semantic and pragmatic functions of V-"le" have remained elusive. While linguists and grammarians…

  7. Energy levels, wavelengths, and radiative transition probabilities for the Na-like ions with 38 [le] Z [le] 45

    SciTech Connect

    Ying Zhang; Qiren Zhu; Shoufu Pan )

    1992-11-01

    The investigation by Z.-Q Zhang et al. (Acta Optica Sinica 11, 193, 1991) shows that it is possible to realize soft X-ray lasing in the water window 23.3-43.8 [Angstrom] with the Na-like recombination scheme, which requires a lower pumping power at a high-power laser facility than that with other schemes. The fine-structure levels with n [le] 15 and l [le] 6 in Na-like ions with 38 [le] Z [le] 45 and the probabilities for radiative transitions between these levels are calculated using the multiconfiguration Dirac-Fock approach. The calculations show that the wavelengths of the anticipated laser transitions 6 f-4d and 6g-4f in the Na-like ions with 38 [le] Z [le] 43 and 5f-4d and 5g-4f in the Na-like ions with 40 [le] Z [le] 45 lie in the region of the water window.

  8. Viruses of lower vertebrates.

    PubMed

    Essbauer, S; Ahne, W

    2001-08-01

    Viruses of lower vertebrates recently became a field of interest to the public due to increasing epizootics and economic losses of poikilothermic animals. These were reported worldwide from both wildlife and collections of aquatic poikilothermic animals. Several RNA and DNA viruses infecting fish, amphibians and reptiles have been studied intensively during the last 20 years. Many of these viruses induce diseases resulting in important economic losses of lower vertebrates, especially in fish aquaculture. In addition, some of the DNA viruses seem to be emerging pathogens involved in the worldwide decline in wildlife. Irido-, herpes- and polyomavirus infections may be involved in the reduction in the numbers of endangered amphibian and reptile species. In this context the knowledge of several important RNA viruses such as orthomyxo-, paramyxo-, rhabdo-, retro-, corona-, calici-, toga-, picorna-, noda-, reo- and birnaviruses, and DNA viruses such as parvo-, irido-, herpes-, adeno-, polyoma- and poxviruses, is described in this review. PMID:11550762

  9. Vaccinia virus transcription.

    PubMed

    Broyles, Steven S

    2003-09-01

    Vaccinia virus replication takes place in the cytoplasm of the host cell. The nearly 200 kbp genome owes part of its complexity to encoding most of the proteins involved in genome and mRNA synthesis. The multisubunit vaccinia virus RNA polymerase requires a separate set of virus-encoded proteins for the transcription of the early, intermediate and late classes of genes. Cell fractionation studies have provided evidence for a role for host cell proteins in the initiation and termination of vaccinia virus intermediate and late gene transcription. Vaccinia virus resembles nuclear DNA viruses in the integration of viral and host proteins for viral mRNA synthesis, yet is markedly less reliant on host proteins than its nuclear counterparts. PMID:12917449

  10. Viruses in Antarctic lakes

    NASA Technical Reports Server (NTRS)

    Kepner, R. L. Jr; Wharton, R. A. Jr; Suttle, C. A.; Wharton RA, J. r. (Principal Investigator)

    1998-01-01

    Water samples collected from four perennially ice-covered Antarctic lakes during the austral summer of 1996-1997 contained high densities of extracellular viruses. Many of these viruses were found to be morphologically similar to double-stranded DNA viruses that are known to infect algae and protozoa. These constitute the first observations of viruses in perennially ice-covered polar lakes. The abundance of planktonic viruses and data suggesting substantial production potential (relative to bacteria] secondary and photosynthetic primary production) indicate that viral lysis may be a major factor in the regulation of microbial populations in these extreme environments. Furthermore, we suggest that Antarctic lakes may be a reservoir of previously undescribed viruses that possess novel biological and biochemical characteristics.

  11. Constructing computer virus phylogenies

    SciTech Connect

    Goldberg, L.A.; Goldberg, P.W.; Phillips, C.A.; Sorkin, G.B.

    1996-03-01

    There has been much recent algorithmic work on the problem of reconstructing the evolutionary history of biological species. Computer virus specialists are interested in finding the evolutionary history of computer viruses--a virus is often written using code fragments from one or more other viruses, which are its immediate ancestors. A phylogeny for a collection of computer viruses is a directed acyclic graph whose nodes are the viruses and whose edges map ancestors to descendants and satisfy the property that each code fragment is ``invented`` only once. To provide a simple explanation for the data, we consider the problem of constructing such a phylogeny with a minimal number of edges. In general, this optimization problem cannot be solved in quasi-polynomial time unless NQP=QP; we present positive and negative results for associated approximated problems. When tree solutions exist, they can be constructed and randomly sampled in polynomial time.

  12. Water system virus detection

    NASA Technical Reports Server (NTRS)

    Fraser, A. S.; Wells, A. F.; Tenoso, H. J. (Inventor)

    1978-01-01

    The performance of a waste water reclamation system is monitored by introducing a non-pathogenic marker virus, bacteriophage F2, into the waste-water prior to treatment and, thereafter, testing the reclaimed water for the presence of the marker virus. A test sample is first concentrated by absorbing any marker virus onto a cellulose acetate filter in the presence of a trivalent cation at low pH and then flushing the filter with a limited quantity of a glycine buffer solution to desorb any marker virus present on the filter. Photo-optical detection of indirect passive immune agglutination by polystyrene beads indicates the performance of the water reclamation system in removing the marker virus. A closed system provides for concentrating any marker virus, initiating and monitoring the passive immune agglutination reaction, and then flushing the system to prepare for another sample.

  13. The human oncogenic viruses

    SciTech Connect

    Luderer, A.A.; Weetall, H.H

    1986-01-01

    This book contains eight selections. The titles are: Cytogenetics of the Leukemias and Lymphomas; Cytogenetics of Solid Tumors: Renal Cell Carcinoma, Malignant Melanoma, Retinoblastoma, and Wilms' Tumor; Elucidation of a Normal Function for a Human Proto-Oncogene; Detection of HSV-2 Genes and Gene Products in Cervical Neoplasia; Papillomaviruses in Anogennital Neoplasms; Human Epstein-Barr Virus and Cancer; Hepatitis B Virus and Hepatocellular Carcinoma; and Kaposi's Sarcoma: Acquired Immunodeficiency Syndrome (AIDS) and Associated Viruses.

  14. Water system virus detection

    NASA Technical Reports Server (NTRS)

    Fraser, A. S.; Wells, A. F.; Tenoso, H. J.

    1975-01-01

    A monitoring system developed to test the capability of a water recovery system to reject the passage of viruses into the recovered water is described. A nonpathogenic marker virus, bacteriophage F2, is fed into the process stream before the recovery unit and the reclaimed water is assayed for its presence. Detection of the marker virus consists of two major components, concentration and isolation of the marker virus, and detection of the marker virus. The concentration system involves adsorption of virus to cellulose acetate filters in the presence of trivalent cations and low pH with subsequent desorption of the virus using volumes of high pH buffer. The detection of the virus is performed by a passive immune agglutination test utilizing specially prepared polystyrene particles. An engineering preliminary design was performed as a parallel effort to the laboratory development of the marker virus test system. Engineering schematics and drawings of a fully functional laboratory prototype capable of zero-G operation are presented. The instrument consists of reagent pump/metering system, reagent storage containers, a filter concentrator, an incubation/detector system, and an electronic readout and control system.

  15. Residual viruses in pork products.

    PubMed

    McKercher, P D; Hess, W R; Hamdy, F

    1978-01-01

    Partly cooked canned hams and dried pepperoni and salami sausages were prepared from the carcasses of pigs infected with African swine fever virus and pigs infected with hog cholera virus. Virus was not recovered from the partly cooked canned hams; however, virus was recovered in the hams before heating in both instances. Both African swine fever virus and hog cholera virus were recovered from the dried salami and pepperoni sausages, but not after the required curing period. PMID:564162

  16. Ebola Virus and Severe Acute Respiratory Syndrome Coronavirus Display Late Cell Entry Kinetics: Evidence that Transport to NPC1+ Endolysosomes Is a Rate-Defining Step

    PubMed Central

    Mingo, Rebecca M.; Simmons, James A.; Shoemaker, Charles J.; Nelson, Elizabeth A.; Schornberg, Kathryn L.; D'Souza, Ryan S.; Casanova, James E.

    2014-01-01

    ABSTRACT Ebola virus (EBOV) causes hemorrhagic fevers with high mortality rates. During cellular entry, the virus is internalized by macropinocytosis and trafficked through endosomes until fusion between the viral and an endosomal membrane is triggered, releasing the RNA genome into the cytoplasm. We found that while macropinocytotic uptake of filamentous EBOV viruslike particles (VLPs) expressing the EBOV glycoprotein (GP) occurs relatively quickly, VLPs only begin to enter the cytoplasm after a 30-min lag, considerably later than particles bearing the influenza hemagglutinin or GP from lymphocytic choriomeningitis virus, which enter through late endosomes (LE). For EBOV, the long lag is not due to the large size or unusual shape of EBOV filaments, the need to prime EBOV GP to the 19-kDa receptor-binding species, or a need for unusually low endosomal pH. In contrast, since we observed that EBOV entry occurs upon arrival in Niemann-Pick C1 (NPC1)-positive endolysosomes (LE/Lys), we propose that trafficking to LE/Lys is a key rate-defining step. Additional experiments revealed, unexpectedly, that severe acute respiratory syndrome (SARS) S-mediated entry also begins only after a 30-min lag. Furthermore, although SARS does not require NPC1 for entry, SARS entry also begins after colocalization with NPC1. Since the only endosomal requirement for SARS entry is cathepsin L activity, we tested and provide evidence that NPC1+ LE/Lys have higher cathepsin L activity than LE, with no detectable activity in earlier endosomes. Our findings suggest that both EBOV and SARS traffic deep into the endocytic pathway for entry and that they do so to access higher cathepsin activity. IMPORTANCE Ebola virus is a hemorrhagic fever virus that causes high fatality rates when it spreads from zoonotic vectors into the human population. Infection by severe acute respiratory syndrome coronavirus (SARS-CoV) causes severe respiratory distress in infected patients. A devastating outbreak of EBOV

  17. Les Hemorragies Gastroduodenales de Stress Chez le Brule Grave

    PubMed Central

    Siah, S.; Fouadi, F.E.; Ababou, K.; Nassim Sabah, T.; Ihrai, I.

    2008-01-01

    Summary Les Auteurs rapportent trois observations d'hémorragies gastroduodénales de stress chez le brûlé grave. Ils rappellent l'importance des mesures thérapeutiques qui doivent être prises chez le brûlé grave, comme le traitement du choc, du sepsis, des plaies et de la douleur, la nutrition entérale précoce et l'oxygénothérapie. Tout cela permet de réduire les facteurs de risque de survenue d'une hémorragie gastroduodénale de stress. PMID:21991137

  18. Automated Verification of Design Patterns with LePUS3

    NASA Technical Reports Server (NTRS)

    Nicholson, Jonathan; Gasparis, Epameinondas; Eden, Ammon H.; Kazman, Rick

    2009-01-01

    Specification and [visual] modelling languages are expected to combine strong abstraction mechanisms with rigour, scalability, and parsimony. LePUS3 is a visual, object-oriented design description language axiomatized in a decidable subset of the first-order predicate logic. We demonstrate how LePUS3 is used to formally specify a structural design pattern and prove ( verify ) whether any JavaTM 1.4 program satisfies that specification. We also show how LePUS3 specifications (charts) are composed and how they are verified fully automatically in the Two-Tier Programming Toolkit.

  19. INFLUENZA VIRUS IN POULTRY

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Avian influenza virus (AIV) is normally found in wild birds, particularly in ducks and shorebirds, where it does not cause any perceptible clinical disease. However, poultry, including chickens and turkeys, are not normal hosts for avian influenza, but if the virus is introduced it can result in mi...

  20. Zika Virus Disease.

    PubMed

    Slenczka, Werner

    2016-06-01

    The history of Zika virus disease serves as a paradigm of a typical emerging viral infection. Zika virus disease, a mosquito-borne flavivirus, was first isolated in 1947 in the Zika forest of Uganda. The same virus was also isolated from jungle-dwelling mosquitoes (Aedes [Stegomyia] africanus). In many areas of Africa and South Asia human infections with Zika virus were detected by both serology and virus isolation. About 80% of infections are asymptomatic, and in 20% a mostly mild disease with fever, rash, arthralgia, and conjunctivitis may occur. Fetal infections with malformations were not recorded in Africa or Asia. Zika virus was imported to northern Brazil possibly during the world soccer championship that was hosted by Brazil in June through July 2014. A cluster of severe fetal malformations with microcephaly and ocular defects was noted in 2015 in the northeast of Brazil, and intrauterine infections with Zika virus were confirmed. The dramatic change in Zika virus pathogenicity upon its introduction to Brazil has remained an enigma. PMID:27337468

  1. Human Papilloma Virus Infections

    PubMed Central

    Wright, V. Cecil

    1989-01-01

    Genital warts are believed to be caused by human papilloma viruses and to be sexually transmitted. The viruses are classified by DNA types, which appear to cause different types of disease. The choice of treatment, and usually its success rate, vary according to the type of disease and its location. PMID:21248973

  2. Barley Yellow Dwarf Virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Barley yellow dwarf (BYD) is the most widespread and economically important virus disease of cereals. The viruses causing BYD were initially grouped based on common biological properties, including persistent and often strain-specific transmission by aphids and induction of yellowing symptoms. The...

  3. Influenza A virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Influenza A viruses are important veterinary and human health pathogens around the world. Avian influenza (AI) virus in poultry is unusual in that it can cause a range of disease symptoms from a subclinical infection to being highly virulent with 100% mortality. The difference between low pathogen...

  4. Zika Virus and Pregnancy.

    PubMed

    Stagg, Denise; Hurst, Helen M

    2016-01-01

    Recent outbreaks of Zika virus and reports linking infection in pregnant women with microcephaly in newborns have caused concern worldwide. Information has been evolving rapidly. Nurses and other clinicians, especially those who work with women of childbearing age, play a pivotal role in disseminating accurate information and identifying potential cases of Zika virus infection. PMID:27287356

  5. Papaya ringspot virus (Potyviridae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Papaya ringspot virus, a member of the family Potyviridae, is single stranded RNA plant virus with a monocistronic genome of about 10,326 nucleotides that is expressed via a large polyprotein subsequently cleaved into functional proteins. It causes severe damage on cucurbit crops such as squash and...

  6. Virus separation using membranes.

    PubMed

    Grein, Tanja A; Michalsky, Ronald; Czermak, Peter

    2014-01-01

    Industrial manufacturing of cell culture-derived viruses or virus-like particles for gene therapy or vaccine production are complex multistep processes. In addition to the bioreactor, such processes require a multitude of downstream unit operations for product separation, concentration, or purification. Similarly, before a biopharmaceutical product can enter the market, removal or inactivation of potential viral contamination has to be demonstrated. Given the complexity of biological solutions and the high standards on composition and purity of biopharmaceuticals, downstream processing is the bottleneck in many biotechnological production trains. Membrane-based filtration can be an economically attractive and efficient technology for virus separation. Viral clearance, for instance, of up to seven orders of magnitude has been reported for state of the art polymeric membranes under best conditions.This chapter summarizes the fundamentals of virus ultrafiltration, diafiltration, or purification with adsorptive membranes. In lieu of an impractical universally applicable protocol for virus filtration, application of these principles is demonstrated with two examples. The chapter provides detailed methods for production, concentration, purification, and removal of a rod-shaped baculovirus (Autographa californica M nucleopolyhedrovirus, about 40 × 300 nm in size, a potential vector for gene therapy, and an industrially important protein expression system) or a spherical parvovirus (minute virus of mice, 22-26 nm in size, a model virus for virus clearance validation studies). PMID:24297430

  7. Papaya Ringspot Virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The term papaya ringspot virus (PRSV) was coined by Jensen in 1949, to describe a papaya disease in Hawaii. Later work showed that diseases such as papaya mosaic and watermelon mosaic virus-1 were caused by PRSV. The primary host range of PRSV is papaya and cucurbits, with Chenopium amaranticolor ...

  8. Bovine viral diarrhea viruses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Infections with bovine viral diarrhea viruses (BVDV) result in significant economic losses for beef and dairy producers worldwide. BVDV is actually an umbrella term for two species of viruses, BVDV1 and BVDV2, within the Pestivirus genus of the Flavivirus family. While denoted as a bovine pathogen...

  9. Equine Arteritis Virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    03. Nidovirales : 03.004. Arteriviridae : 03.004.0. {03.004.0. unknown} : 03.004.0.01. Arterivirus : 03.004.0.01.001. Equine arteritis virus will be published online. The article details the phenotypic and genotypic makeup of equine arteritis virus (EAV), and summarizes its biological properties....

  10. Rift Valley Fever Virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rift Valley fever virus (RVFV) is a mosquito-transmitted virus or arbovirus that is endemic in sub-Saharan Africa. In the last decade, Rift Valley fever (RVF) outbreaks have resulted in loss of human and animal life, as well as had significant economic impact. The disease in livestock is primarily a...

  11. The LeATL6-associated ubiquitin/proteasome system may contribute to fungal elicitor-activated defense response via the jasmonic acid-dependent signaling pathway in tomato.

    PubMed

    Hondo, Daisuke; Hase, Shu; Kanayama, Yoshinori; Yoshikawa, Nobuyuki; Takenaka, Shigehito; Takahashi, Hideki

    2007-01-01

    The expression of LeATL6, an ortholog of Arabidopsis ATL6 that encodes a RING-H2 finger protein, was induced in tomato roots treated with a cell wall protein fraction (CWP) elicitor of the biocontrol agent Pythium oligandrum. The LeATL6 protein was expressed as a fusion protein with a maltose-binding protein (MBP) in Escherichia coli, and it catalyzed the transfer of ubiquitin to the MBP moiety on incubation with ubiquitin, the ubiquitin-activating enzyme E1, and the ubiquitin-conjugating enzyme E2; this indicated that LeATL6 represents ubiquitin ligase E3. LeATL6 expression also was induced by elicitor treatment of jail-1 mutant tomato cells in which the jasmonic acid (JA)-mediated signaling pathway was impaired; however, JA-dependent expression of the basic PR-6 and TPI-1 genes that encode proteinase inhibitor II and I, respectively, was not induced in elicitor-treated jail-1 mutants. Furthermore, transient overexpression of LeATL6 under the control of the Cauliflower mosaic virus 35S promoter induced the basic PR6 and TPI-1 expression in wild tomato but not in the jail-1 mutant. In contrast, LeATL6 overexpression did not activate salicylic acid-responsive acidic PR-1 and PR-2 promoters in wild tomato. These results indicated that elicitor-responsive LeATL6 probably regulates JA-dependent basic PR6 and TPI-1 gene expression in tomato. The LeATL6-associated ubiquitin/proteasome system may contribute to elicitor-activated defense responses via a JA-dependent signaling pathway in plants. PMID:17249424

  12. Impact de la varicocèle sur le volume testiculaire et les paramètres spermatiques

    PubMed Central

    Benazzouz, Mohamed Hicham; Essatara, Younes; El Sayegh, Hachem; Iken, Ali; Benslimane, Lounis; Nouini, Yassine

    2014-01-01

    Introduction La varicocèle est une pathologie masculine fréquente dont l'incidence est encore plus importante dans dans la population des hommes infertiles. Si ses mécanismes sont à ce jour incomplètement expliqués il semble acquis que la varicocèle peut être associée a une dysfonction testiculaire avec diminution du volume testiculaire et de la concentration en spermatozoïde de l’éjaculat. Méthodes Dans un premier temps nous exposons les résultats d'une étude rétrospective sur 5 ans (de Mars 2009 à Mars 2014), réalisée au service d'urologie A de l'hôpital Ibn Sina de Rabat et ayant comme objectif d’évaluer l'impact de la varicocèle palpable sur le volume testiculaire et les paramètres spermatiques. Tous les patients inclus dans notre étude avaient une varicocèle palpable. Dans un deuxième temps, et à travers une revue de la littérature nous discutons l'impact du traitement de la varicocèle sur la fertilité. Résultats 39 patients ont été inclus dans notre étude. L’âge moyen était de 29,71 ans et la varicocèle siégeait dans 89,74% des cas du coté gauche. Une atrophie testiculaire homolatérale à la varicocèle était retrouvée dans 7% des cas alors que des anomalies du spermogramme se voyaient dans 69,23% des cas. Conclusion L'impact de la varicocèle sur l'altération des paramètres spermatiques a été clairement établi bien que sa physio pathogénie ne soit pas bien élucidée. Le traitement chirurgical de la varicocèle semble indiqué chez les hommes infertiles présentant une varicocèle clinique et une altération significative du sperme. PMID:25918574

  13. Respiratory viruses and children.

    PubMed

    Heikkinen, Terho

    2016-07-01

    Respiratory viruses place a great disease burden especially on the youngest children in terms of high rates of infection, bacterial complications and hospitalizations. In developing countries, some viral infections are even associated with substantial mortality in children. The interaction between viruses and bacteria is probably much more common and clinically significant than previously understood. Respiratory viruses frequently initiate the cascade of events that ultimately leads to bacterial infection. Effective antiviral agents can substantially shorten the duration of the viral illness and prevent the development of bacterial complications. Viral vaccines have the potential to not only prevent the viral infection but also decrease the incidence of bacterial complications. At present, antivirals and vaccines are only available against influenza viruses, but new vaccines and antivirals against other viruses, especially for RSV, are being developed. PMID:27177731

  14. Infectious Viral Quantification of Chikungunya Virus-Virus Plaque Assay.

    PubMed

    Kaur, Parveen; Lee, Regina Ching Hua; Chu, Justin Jang Hann

    2016-01-01

    The plaque assay is an essential method for quantification of infectious virus titer. Cells infected with virus particles are overlaid with a viscous substrate. A suitable incubation period results in the formation of plaques, which can be fixed and stained for visualization. Here, we describe a method for measuring Chikungunya virus (CHIKV) titers via virus plaque assays. PMID:27233264

  15. Development status of LE-7 fuel turbopump

    NASA Astrophysics Data System (ADS)

    Nakano, T.; Nagao, R.; Ohta, T.; Warashina, S.; Watanabe, H.; Oguchi, H.

    The liquid hydrogen turbopump (LH2 T/P) for the LE-7 engine has been developed since 1984. The component PDR was held in June 1988 and the basic troubles occurred at the development test were solved. Next, the component CDR-1 was held in December 1989 in order to feed back the test results of prototype LH2 T/P model to the design of qualification phase T/P. So, the production of these turbopumps was admitted. Recently, the component CDR-2 was held in February 1992 to reflect the counterparts adopted for some troubles (impeller and turbine blade cracks and so on) in long-time engine tests to the design of qualification phase T/P. In the qualification phase, the hydraulic characteristics and strength in the engine operating range were examined at the LH2 T/P component test, and its endurance confirmed at the engine tests. The LH2 turbopump component test was held at NASDA Kakuda and the engine test at Tashiro and Tanegashima. This paper describes the development status of LH2 T/P, containing the design description and the content of some troubles and its counterplans.

  16. L'astronomie dans le monde

    NASA Astrophysics Data System (ADS)

    Manfroid, J.

    2007-09-01

    Anions interstellaires; S Orionis; Altaîr; Courants stellaires; Etoiles jeunes; 2MASSW J1207334-393254; Alpha Andromède; Etoiles à neutrons (1); LH54-425; AGNs invisibles; Deux supernovae; Les GRBs seon Swift; Peser les trous noirs; Formation de trous noirs; Trou noir; ondes gravitationnelles : Virgo entre dans sa phase d'exploitation scientifique; Amas de galaxies actifs; Amas de galaxies; Galaxies actives d'amas; L'univers statique: le retour; Macho; Exoplanètes; Exoplanètes habitables?; Exoplanètes habitables? (suite); Une année d'un an; Une année de 31 heures; Valse des Jupiters; Disque de HD 15115; Impact majeur; Planètes isolées; Super-Jupiter; Impact et mini-extinction; L'effet Pioneer; Toungouska; Spéléo martienne; Autres lunes dactives; Encelade; Hypérion; Pluton dépassé; Satellites d'Uranus; Titan

  17. Transmaxillary Sinus Approach for Le Fort II Osteotomy

    PubMed Central

    Fukawa, Toshihiko; Hirakawa, Takashi; Satake, Toshihiko; Maegawa, Jiro

    2016-01-01

    Summary: The Le Fort II osteotomy is a relatively rare operation. The posterior wall osteotomy of the maxillary sinus (MS) is often difficult for Le Fort III. We developed the transmaxillary sinus approach (TSA) for the Le Fort II osteotomy that cuts the posterior wall of the MS directly. This report illustrates this easy-to-use procedure for the Le Fort II osteotomy in syndromic craniosynostosis. This procedure was performed in an 18-year-old patient with Apert syndrome and a 15-year-old patient with Pfeiffer syndrome. The thin anterior walls of the MS were removed through an intraoral approach to look inside the MS. Then, the posterior walls were cut by chisel under direct vision using light. The other osteotomy was performed as usual. Distraction osteogenesis with internal and external devices was used in combination. The advantages of TSA are the direct posterior wall osteotomy of the MS with no down fracture and minimal invasiveness to the mucosa of the MS under direct vision. However, the disadvantage is that TSA becomes a blind procedure in a case with no MS or hypoplasia. We developed the TSA for the Le Fort II osteotomy, which could provide direct observation and perform the posterior wall osteotomy of the MS without down fracture. We believe that TSA is an effective surgical procedure for the Le Fort II osteotomy. PMID:27014548

  18. Transmaxillary Sinus Approach for Le Fort II Osteotomy.

    PubMed

    Kobayashi, Shinji; Fukawa, Toshihiko; Hirakawa, Takashi; Satake, Toshihiko; Maegawa, Jiro

    2016-02-01

    The Le Fort II osteotomy is a relatively rare operation. The posterior wall osteotomy of the maxillary sinus (MS) is often difficult for Le Fort III. We developed the transmaxillary sinus approach (TSA) for the Le Fort II osteotomy that cuts the posterior wall of the MS directly. This report illustrates this easy-to-use procedure for the Le Fort II osteotomy in syndromic craniosynostosis. This procedure was performed in an 18-year-old patient with Apert syndrome and a 15-year-old patient with Pfeiffer syndrome. The thin anterior walls of the MS were removed through an intraoral approach to look inside the MS. Then, the posterior walls were cut by chisel under direct vision using light. The other osteotomy was performed as usual. Distraction osteogenesis with internal and external devices was used in combination. The advantages of TSA are the direct posterior wall osteotomy of the MS with no down fracture and minimal invasiveness to the mucosa of the MS under direct vision. However, the disadvantage is that TSA becomes a blind procedure in a case with no MS or hypoplasia. We developed the TSA for the Le Fort II osteotomy, which could provide direct observation and perform the posterior wall osteotomy of the MS without down fracture. We believe that TSA is an effective surgical procedure for the Le Fort II osteotomy. PMID:27014548

  19. Three-dimensional Nasolabial Morphologic Alterations Following Le Fort I

    PubMed Central

    DeSesa, Christopher R.; Metzler, Philip; Sawh-Martinez, Rajendra

    2016-01-01

    Background: Le Fort I osteotomy imparts significant changes to the nasolabial region. Past studies have relied on 2-dimensional data and have not delineated differences among various Le Fort I subtypes. The purpose of this study is to 3-dimensionally analyze Le Fort I–induced nasal and lip changes comparing advancement alone versus widening alone [surgically assisted maxillary expansion (SAME)] versus advancement and widening. We hypothesize that the combination of maxillary advancement with widening will result in the most profound changes. Methods: A retrospective cohort study was performed. Included Le Fort I patients were grouped as: (1) nonsegmental straight advancement, (2) widening without advancement, and (3) segmental advancement and widening. Pre- and postoperative 3-dimensional photogrammetry (Canfield) were analyzed. Anthropometric landmarks were placed and measured by 2 independent observers. Statistics involved both paired and unpaired t tests (significance = P < 0.05). Results: One hundred eight photogrammetric data sets were analyzed, including 46 single-piece, 26 SAME, and 36 segmental. Significant postoperative nasal changes were observed within each intragroup analysis. The most dramatic changes were seen after segmental Le Fort I with advancement and widening, which included alar base width, alar width, nostril width, and soft triangle angle, all P < 0.05. Conclusions: Le Fort I osteotomy results in significant alteration of the nasolabial morphology. This is the first study to 3-dimensionally analyze nasal changes that occur comparing maxillary advancement alone versus widening alone (SAME) versus advancement with widening. These objective data permit improved patient counseling and surgical planning. PMID:27622116

  20. Lactobacillus equigenerosi Strain Le1 Invades Equine Epithelial Cells

    PubMed Central

    Botha, Marlie; Botes, Marelize; Loos, Ben; Smith, Carine

    2012-01-01

    Lactobacillus equigenerosi strain Le1, a natural inhabitant of the equine gastrointestinal tract, survived pH 3.0 and incubation in the presence of 1.5% (wt/vol) bile salts for at least 2 h. Strain Le1 showed 8% cell surface hydrophobicity, 60% auto-aggregation, and 47% coaggregation with Clostridium difficile C6. Only 1% of the cells adhered to viable buccal epithelial cells and invaded the cells within 20 min after contact. Preincubation of strain Le1 in a buffer containing pronase prevented adhesion to viable epithelial cells. Preincubation in a pepsin buffer delayed invasion from 20 min to 1 h. Strain Le1 did not adhere to nonviable epithelial cells. Administration of L. equigenerosi Le1 (1 × 109 CFU per 50 kg body weight) to healthy horses did not increase white blood cell numbers. Differential white blood cell counts and aspartate aminotransferase levels remained constant. Glucose, lactate, cholesterol, and urea levels remained constant during administration with L. equigenerosi Le1 but decreased during the week after administration. PMID:22504808

  1. Searching the animal psyche with Charles Le Brun.

    PubMed

    Cohen, Sarah R

    2010-07-01

    Around 1670 the French court painter and Academician Charles Le Brun produced a series of drawings featuring naturalistic animal heads, as well as imaginary heads in which he refashioned various nonhuman animal species to make humanoid physiognomies. What were the purpose and significance of these unusual works? I argue that they show Le Brun's interest in what we today would call animal psychology: focusing upon the sensory organs and their connections with the animal's brain, Le Brun studied his animals as conscious protagonists of the natural realm. One source that may have served him in this project was Marin Cureau de La Chambre's De la Connoissance des bestes of 1645, in which the physician argued that animals possess a conscious soul grounded in the senses. However, Le Brun's animal-humans have no clear place in the artist's taxonomy--nor, indeed, in any seventeenth-century understandings of species. It is rather John Locke, at his most skeptical, who offers the best parallel in the realm of natural philosophy to Le Brun's unsettling animal-humans. Probably without meaning to, Le Brun demonstrated through his eerie, boundary-crossing creatures the limits of visual classification. PMID:20853815

  2. Antiviral effects of liposome-encapsulated PolyICLC against Dengue virus in a mouse model.

    PubMed

    Hu, Yongxin; Hu, Yanxin; Sun, Lunquan; Wong, Jonathan; Wang, Ming

    2016-09-16

    This study presents the first investigation of the antiviral effects of the liposome-encapsulated PolyICLC (LE-PolyICLC) on Dengue virus (DENV) in a mouse model. In vivo efficacy studies showed that LE-PolyICLC acted to increase antiviral mechanisms mainly through promoting cytokine expression associated with innate immunity, such as IFN-γ. In addition, the pro-inflammatory cytokine TNF-α was also increased, while IL-6 level was decreased in serum. The titers of total antibodies against DENV2 in mice were also elevated. Administration of LE-PolyICLC not only alleviated the loss of body weight, degree of morbidity, and pathological damage in brains, but also reduced the viral titers and expression of viral E protein in the brain. Notably, the effectiveness of LE-PolyICLC was better than PolyICLC on the basis of the data presented in this study. These results, therefore, set a foundation for further development of LE-PolyICLC as an attractive candidate of antiviral agents to be used in both prophylactic and therapeutic settings in DENV diseases. PMID:27524246

  3. Postmortem Stability of Ebola Virus

    PubMed Central

    Prescott, Joseph; Bushmaker, Trenton; Fischer, Robert; Miazgowicz, Kerri; Judson, Seth

    2015-01-01

    The ongoing Ebola virus outbreak in West Africa has highlighted questions regarding stability of the virus and detection of RNA from corpses. We used Ebola virus–infected macaques to model humans who died of Ebola virus disease. Viable virus was isolated <7 days posteuthanasia; viral RNA was detectable for 10 weeks. PMID:25897646

  4. Tembusu Virus in Ducks, China

    PubMed Central

    Cao, Zhenzhen; Zhang, Cun; Liu, Yuehuan; Ye, Weicheng; Han, Jingwen; Ma, Guoming; Zhang, Dongdong; Xu, Feng; Gao, Xuhui; Tang, Yi; Shi, Shaohua; Wan, Chunhe; Zhang, Chen; He, Bin; Yang, Mengjie; Lu, Xinhao; Huang, Yu; Diao, Youxiang; Ma, Xuejun

    2011-01-01

    In China in 2010, a disease outbreak in egg-laying ducks was associated with a flavivirus. The virus was isolated and partially sequenced. The isolate exhibited 87%–91% identity with strains of Tembusu virus, a mosquito-borne flavivirus of the Ntaya virus group. These findings demonstrate emergence of Tembusu virus in ducks. PMID:22000358

  5. Computer Viruses: Pathology and Detection.

    ERIC Educational Resources Information Center

    Maxwell, John R.; Lamon, William E.

    1992-01-01

    Explains how computer viruses were originally created, how a computer can become infected by a virus, how viruses operate, symptoms that indicate a computer is infected, how to detect and remove viruses, and how to prevent a reinfection. A sidebar lists eight antivirus resources. (four references) (LRW)

  6. A Virus in Turbo Pascal.

    ERIC Educational Resources Information Center

    Teleky, Heidi Ann; And Others

    1993-01-01

    Addresses why the authors feel it is not inappropriate to teach about viruses in the how-to, hands-on fashion. Identifies the special features of Turbo Pascal that have to be used for the creation of an effective virus. Defines virus, derives its structure, and from this structure is derived the implemented virus. (PR)

  7. Realms of the Viruses Online

    ERIC Educational Resources Information Center

    Liu, Dennis

    2007-01-01

    Viruses have evolved strategies for infecting all taxa, but most viruses are highly specific about their cellular host. In humans, viruses cause diverse diseases, from chronic but benign warts, to acute and deadly hemorrhagic fever. Viruses have entertaining names like Zucchini Yellow Mosaic, Semliki Forest, Coxsackie, and the original terminator,…

  8. Le graben de l'Anti-Atlas occidental (Maroc) : contrôle tectonique de la paléogéographie et des séquences au Cambrien inférieurThe Lower-Cambrian western Anti-Atlasic graben: tectonic control of palaeogeography and sequential organisation

    NASA Astrophysics Data System (ADS)

    Benssaou, Mohammed; Hamoumi, Naı̈ma

    2003-03-01

    In the Moroccan western Anti-Atlas, the combined extensive tectonic events with a long-term sea-level rise is the main factor on building vertical stacking transgressive-regressive sequences. In the Ait Abdallah-Boussafene axis, the subsidence processes, relayed by a brutal platform tilting generated an elongated NE-SW graben. This is an evidence of the persistence of the Anti-Atlasic rifting process during the last part of the Lower-Cambrian succession.

  9. Ocular Tropism of Respiratory Viruses

    PubMed Central

    Rota, Paul A.; Tumpey, Terrence M.

    2013-01-01

    SUMMARY Respiratory viruses (including adenovirus, influenza virus, respiratory syncytial virus, coronavirus, and rhinovirus) cause a broad spectrum of disease in humans, ranging from mild influenza-like symptoms to acute respiratory failure. While species D adenoviruses and subtype H7 influenza viruses are known to possess an ocular tropism, documented human ocular disease has been reported following infection with all principal respiratory viruses. In this review, we describe the anatomical proximity and cellular receptor distribution between ocular and respiratory tissues. All major respiratory viruses and their association with human ocular disease are discussed. Research utilizing in vitro and in vivo models to study the ability of respiratory viruses to use the eye as a portal of entry as well as a primary site of virus replication is highlighted. Identification of shared receptor-binding preferences, host responses, and laboratory modeling protocols among these viruses provides a needed bridge between clinical and laboratory studies of virus tropism. PMID:23471620

  10. Viruses of Chelonia.

    PubMed

    Ahne, W

    1993-02-01

    Viruses occurring in turtles and tortoises are hetergeneous but according to ecologic characteristics and pathogenic properties they can be divided in two major groups: 1. Arboviruses (toga-, flavi-, rhabdo- and bunyaviruses) transmitted by arthropods cause severe diseases in homoiothermic vertebrates. The viruses are of great epidemiological interest in human and veterinary medicine. Chelonia and other reptiles infected by bites of vectors e.g. Aedes, Anopheles, Culex develop cyclic viremia without injury. The ectothermic animals maintain inapparent arbovirus infections during hibernation and they play role as reservoirs for these viruses. 2. Viruses of Chelonia origin (papova-, herpes-, irido- and paramyxoviruses) associated with diseases of infected turtles and tortoises have been described frequently during the last 20 years. Several viruses or virus-like particles could be demonstrated in affected reptiles mainly by electron microscopy. Especially herpesviruses seem to attack Chelonia and epizootics due to infections with these viruses were reported in several reptiles in collections. However, the etiological role of the agents detected is not well documented yet. PMID:8456570

  11. Le Point sur la Pharmacologie des Agents Anesthesiques Chez le Brule Grave

    PubMed Central

    Siah, S.; Ababou, K.; Benziane, H.; El Jaoudi; Bensghir, M.; Bakali, H.; El Wali, A.; Ihrai, I.; Drissi, N.K.

    2008-01-01

    Summary La pharmacologie des agents anesthésiques chez le brûlé est variable et imprévisible. Dans les premières 48 h, il y a une hypovolémie avec chute du débit cardiaque et des fuites plasmatiques. Après 48 h, il y a une hypervolémie avec augmentation du débit cardiaque, hypermétabolisme et la clearance des médicaments est augmentée. Parmi les facteurs de déséquilibre, on retrouve les variations des protéines plasmatiques. Deux protéines sont importantes chez le brûlé grave : l'albumine et l'alpha 1- glycoprotéine. Leur taux varie beaucoup au cours de l'évolution de la brûlure. Les agents anesthésiques dont la liaison avec ces deux protéines est prédominante verront leur pharmacocinétique modifiée. L'anesthésiste-réanimateur du service des brûlés va maîtriser ces notions pharmacologiques pour utiliser à bon escient les agents anesthésiques. PMID:21991108

  12. Synthesis of a BSA-Le(x) glycoconjugate and recognition of Le(x) analogues by the anti-Le(x) monoclonal antibody SH1: the identification of a non-cross reactive analogue.

    PubMed

    Wang, Jo-Wen; Asnani, Ari; Auzanneau, France-Isabelle

    2010-10-15

    A Le(x) trisaccharide functionalized with a cysteamine arm was prepared and this synthesis provided additional information on the reactivity of N-acetylglucosamine O-4 acceptors when they are glycosylated with trichloroacetimidate donors activated with excess BF(3)·OEt(2). In turn, this trisaccharide was conjugated to BSA lysine side chains through a squarate-mediated coupling. This BSA-Le(x) glycoconjugate displayed 35 Le(x) haptens per BSA molecule. The relative affinity of the anti-Le(x) monoclonal antibody SH1 for the Le(x) antigen and analogues of Le(x) in which the D-glucosamine, L-fucose or D-galactose residues were replaced with D-glucose, L-rhamnose and D-glucose, respectively, was measured by competitive ELISA experiments. While all analogues were weaker inhibitors than the Le(x) antigen, only the analogue of Le(x) in which the galactose residue was replaced by a glucose unit showed no binding to the SH1 mAb. To confirm that the reduced or loss of recognition of the Le(x) analogues by the anti-Le(x) mAb SH1 did not result from different conformations adopted by the analogues when compared to the native Le(x) antigen, we assessed the conformational behavior of all trisaccharides by a combination of stochastic searches and NMR experiments. Our results showed that, indeed, the analogues adopted the same stacked conformation as that identified for the Le(x) antigen. The identification of a trisaccharide analogue that does not cross-react with Le(x) but still retains the same conformation as Le(x) constitutes the first step to the design of a safe anti-cancer vaccine based on the dimeric Le(x) tumor associated carbohydrate antigen. PMID:20843695

  13. Un exemple de transfert de technologie dans le domaine des polymères conducteurs : le projet ``HYRA"

    NASA Astrophysics Data System (ADS)

    Parneix, J. P.; Miane, J. L.; Colin, T.; Ruffie, G.; Mege, J.

    1998-06-01

    The HYRA project is a response to the restructuration of local companies : these are purveyors of high technology military and spatial especially in the radars business. Furthermore, the development of mobile communications needs devices and materials in the millimeter range (from 20 to 100Ghz). The aim of the HYRA project is the development of materials with specific properties - particularly conducting materials - in the millimeter wave range. The results obtained on thermoplastic/conducting polymer composites are presented. Le projet HYRA répond à des préoccupations régionales liées à des restructurations industrielles : les industries régionales fournissant les marchés militaires et spatiaux disposent de techniques très performantes mais coûteuses, en particulier dans le domaine des radars. Par ailleurs le développement des communications mobiles a besoin de dispositifs et de matériaux dans tout le domaine millimétrique (de 20 à 100 Ghz). Le projet HYRA a pour but le développement de matériaux à propriétés spécifiques - en particulier conducteurs - dans ce domaine de fréquence. Les résultats obtenus sur des composites thermoplastiques/polymères conducteurs sont présentés.

  14. Foamy virus vectors.

    PubMed Central

    Russell, D W; Miller, A D

    1996-01-01

    Human foamy virus (HFV) is a retrovirus of the spumavirus family. We have constructed vectors based on HFV that encode neomycin phosphotransferase and alkaline phosphatase. These vectors are able to transduce a wide variety of vertebrate cells by integration of the vector genome. Unlike vectors based on murine leukemia virus, HFV vectors are not inactivated by human serum, and they transduce stationary-phase cultures more efficiently than murine leukemia virus vectors. These properties, as well as their large packaging capacity, make HFV vectors promising gene transfer vehicles. PMID:8523528

  15. Fighting cancer with viruses

    NASA Astrophysics Data System (ADS)

    Ferreira, S. C.; Martins, M. L.; Vilela, M. J.

    2005-01-01

    One of the most promising strategies to treat cancer is attacking it with viruses. Viruses can kill tumor cells specifically or act as carriers that deliver normal genes into cancer cells. A model for virotherapy of cancer is investigated and its predictions are in agreement with results obtained from experimental tumors. Furthermore, the model reveals an oscillatory (periodic or aperiodic) response of tumor cells and virus populations which may make clinical prognosis difficult. These results suggest the need for new in vivo and in vitro experiments aiming to detect this oscillatory response.

  16. Virus templated metallic nanoparticles.

    PubMed

    Aljabali, Alaa A A; Barclay, J Elaine; Lomonossoff, George P; Evans, David J

    2010-12-01

    Plant viruses are considered as nanobuilding blocks that can be used as synthons or templates for novel materials. Cowpea mosaic virus (CPMV) particles have been shown to template the fabrication of metallic nanoparticles by an electroless deposition metallization process. Palladium ions were electrostatically bound to the virus capsid and, when reduced, acted as nucleation sites for the subsequent metal deposition from solution. The method, although simple, produced highly monodisperse metallic nanoparticles with a diameter of ca. ≤35 nm. CPMV-templated particles were prepared with cobalt, nickel, iron, platinum, cobalt-platinum and nickel-iron. PMID:20877898

  17. Viruses in reptiles

    PubMed Central

    2011-01-01

    The etiology of reptilian viral diseases can be attributed to a wide range of viruses occurring across different genera and families. Thirty to forty years ago, studies of viruses in reptiles focused mainly on the zoonotic potential of arboviruses in reptiles and much effort went into surveys and challenge trials of a range of reptiles with eastern and western equine encephalitis as well as Japanese encephalitis viruses. In the past decade, outbreaks of infection with West Nile virus in human populations and in farmed alligators in the USA has seen the research emphasis placed on the issue of reptiles, particularly crocodiles and alligators, being susceptible to, and reservoirs for, this serious zoonotic disease. Although there are many recognised reptilian viruses, the evidence for those being primary pathogens is relatively limited. Transmission studies establishing pathogenicity and cofactors are likewise scarce, possibly due to the relatively low commercial importance of reptiles, difficulties with the availability of animals and permits for statistically sound experiments, difficulties with housing of reptiles in an experimental setting or the inability to propagate some viruses in cell culture to sufficient titres for transmission studies. Viruses as causes of direct loss of threatened species, such as the chelonid fibropapilloma associated herpesvirus and ranaviruses in farmed and wild tortoises and turtles, have re-focused attention back to the characterisation of the viruses as well as diagnosis and pathogenesis in the host itself. 1. Introduction 2. Methods for working with reptilian viruses 3. Reptilian viruses described by virus families 3.1. Herpesviridae 3.2. Iridoviridae 3.2.1 Ranavirus 3.2.2 Erythrocytic virus 3.2.3 Iridovirus 3.3. Poxviridae 3.4. Adenoviridae 3.5. Papillomaviridae 3.6. Parvoviridae 3.7. Reoviridae 3.8. Retroviridae and inclusion body disease of Boid snakes 3.9. Arboviruses 3.9.1. Flaviviridae 3.9.2. Togaviridae 3.10. Caliciviridae

  18. Transitions de phase dans le oxyde de yttrium vanadium

    NASA Astrophysics Data System (ADS)

    Roberge, Benoit

    Dans le mémoire qui suit, les ordres structural, magnétiques et orbital dans le YVO3 sont étudiés avec l'aide de la diffraction des rayons X,de la spectroscopie Raman et de la technique de la cavité résonnante hyperfréquence. L'objectif premier consiste à observer l'évolution de ces ordres en fonction de la température. Le mémoire met ensuite en évidence le couplage entre les différents ordres cohabitants dans le YVO3 . Les mesures effectuées par la diffraction des rayons X permettent de mesurer le caractère polycrystallin des échantillons du YVO 3. Une comparaison de nos mesures avec des mesures de diffraction des rayons X faites sur la poudre de YVO3 indique la faible présence de maclage. Les mesures effectuées avec la technique de résonnance hyperfréquence permettent de suivre l'évolution de la constante diélectrique en fonction de la température. Les changements impliquant l'ordre orbital se manifestent de manière évidente dans la constante diélectrique à 200 K et à 77 K. La transition diélectrique détectée à 77 K est une transition de premier ordre. Un couplage entre les propriétés diélectriques et magnétiques est observable à la température de Néel à 114 K. L'effet d'un champ magnétique fixe sur la température de transition de l'ordre orbital survenant à 77 K est également remarquable. Cela indique un couplage magnétodiélectrique démontrant ainsi le caractère multiferroïque du YVO 3. Finalement, l'observation d'un mécanisme de relaxation pouvant être modélisé par le modèle d'Havriliak-Negami est observé en dessous de 77 K. En utilisant le modèle d'Arrhénius et le modèle d'Havriliak-Negami, on peut caractériser le mécanisme avec son énergie d'activation et son temps de relaxation. Les mesures effectuées en spectroscopie Raman permettent de suivre l'évolution de la structure du YVO3 en fonction de la température. Les deux changements structuraux survenant à 200 K et 77 K sont observés. Le

  19. Bactériophages et phagothérapie: utilisation de virus naturels pour traiter les infections bactériennes

    PubMed Central

    Ravat, F.; Jault, P.; Gabard, J.

    2015-01-01

    Summary L’utilisation des bactériophages, prédateurs naturels des bactéries, est une technique pionnière efficace de lutte contre les infections bactériennes. Tombée dans l’oubli depuis un demi-siècle du coté occidental de l’ex-rideau de fer, elle fait toujours partie de l’arsenal thérapeutique des pays de l’ex-Europe de l’Est, au point de constituer une arme de choix dans la politique de santé publique de ces pays. l’émergence de bactéries multirésistantes et le risque de revenir à l’ère pré-antibiotique ont fait ressortir la phagothérapie de l’oubli injuste auquel elle avait été confinée. la biologie et la place du bactériophage dans la nature sont décrites ici. les tenants et les aboutissants de la phagothérapie et les conditions de son retour sur le devant de la scène sont explicitées. PMID:26668557

  20. How rigid are viruses

    NASA Astrophysics Data System (ADS)

    Hartschuh, R. D.; Wargacki, S. P.; Xiong, H.; Neiswinger, J.; Kisliuk, A.; Sihn, S.; Ward, V.; Vaia, R. A.; Sokolov, A. P.

    2008-08-01

    Viruses have traditionally been studied as pathogens, but in recent years they have been adapted for applications ranging from drug delivery and gene therapy to nanotechnology, photonics, and electronics. Although the structures of many viruses are known, most of their biophysical properties remain largely unexplored. Using Brillouin light scattering, we analyzed the mechanical rigidity, intervirion coupling, and vibrational eigenmodes of Wiseana iridovirus (WIV). We identified phonon modes propagating through the viral assemblies as well as the localized vibrational eigenmode of individual viruses. The measurements indicate a Young’s modulus of ˜7GPa for single virus particles and their assemblies, surprisingly high for “soft” materials. Mechanical modeling confirms that the DNA core dominates the WIV rigidity. The results also indicate a peculiar mechanical coupling during self-assembly of WIV particles.

  1. VIRUS instrument enclosures

    NASA Astrophysics Data System (ADS)

    Prochaska, T.; Allen, R.; Mondrik, N.; Rheault, J. P.; Sauseda, M.; Boster, E.; James, M.; Rodriguez-Patino, M.; Torres, G.; Ham, J.; Cook, E.; Baker, D.; DePoy, Darren L.; Marshall, Jennifer L.; Hill, G. J.; Perry, D.; Savage, R. D.; Good, J. M.; Vattiat, Brian L.

    2014-08-01

    The Visible Integral-Field Replicable Unit Spectrograph (VIRUS) instrument will be installed at the Hobby-Eberly Telescope† in the near future. The instrument will be housed in two enclosures that are mounted adjacent to the telescope, via the VIRUS Support Structure (VSS). We have designed the enclosures to support and protect the instrument, to enable servicing of the instrument, and to cool the instrument appropriately while not adversely affecting the dome environment. The system uses simple HVAC air handling techniques in conjunction with thermoelectric and standard glycol heat exchangers to provide efficient heat removal. The enclosures also provide power and data transfer to and from each VIRUS unit, liquid nitrogen cooling to the detectors, and environmental monitoring of the instrument and dome environments. In this paper, we describe the design and fabrication of the VIRUS enclosures and their subsystems.

  2. Virus Chapter: Iflaviridae

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The iflaviruses comprise viruses isolated from arthropod species of agricultural importance. All members of iflaviruses have a genome arrangement similar to the picornaviruses, ootyviruses, and secoviruses. However, phylogenetic analysis using the RNA-dependent RNA polymerase region showed that th...

  3. [Zika, a neurotropic virus?].

    PubMed

    Del Carpio-Orantes, Luis

    2016-01-01

    In this paper, the neurotropism potential Zika virus is discussed, by comparison with viruses both RNA and DNA are neurotropic known, also it is said that compared with the new viruses that have affected the Americas, as the chikungunya, Zika has shown great affinity by brain tissue, manifested by a high incidence of acute neurological conditions, such as Guillain-Barré syndrome, among others, as well as the reported incidence of microcephaly that is abnormally high compared with the previous incidence, which, in a stillborn subject necropsied significant alterations demonstrated in brain tissue, identifying viral material and live virus in the fetoplacental complex, and demonstrating the impact both white matter and gray matter as well as basal ganglia, corpus callosum, ventricles and spinal cord, which could explain the microcephaly that concerns him. Although not a direct cause-effect relationship is demonstrated, however current evidence supports that relationship, hoping to be supported scientifically. PMID:27197113

  4. Sexually transmitted viruses.

    PubMed Central

    Rapp, F.

    1989-01-01

    Human viruses known to be spread by sexual contact include herpes simplex viruses (HSV), papillomaviruses (HPV), human immunodeficiency virus (HIV), hepatitis B virus, and cytomegalovirus. Infections with the first three (HSV, HPV, and HIV) have reached epidemic proportions and pose global health concerns. Most of what we know about these human pathogens has been learned only recently, owing to the advent of DNA technologies and advances in culture techniques. In fact, our awareness of one virally transmitted venereal disease, acquired immunodeficiency syndrome, dates to the early 1980s. This paper touches on various aspects of the biology, pathogenesis, clinical manifestations, and, where applicable, oncogenicity of these agents, as well as current treatments and vaccine initiatives. PMID:2549736

  5. West Nile Virus

    MedlinePlus

    ... to human beings through their bites. Credit: CDC Biology, Genetics, & Clinical Research NIAID conducts and funds basic and clinical research on WNV biology and viral structure, ways the virus causes human ...

  6. Respiratory syncytial virus (RSV)

    MedlinePlus

    ... RSV often spreads quickly in crowded households and day care centers. The virus can live for a half ... The following increase the risk for RSV: Attending day care Being near tobacco smoke Having school-aged brothers ...

  7. Hepatitis B virus (image)

    MedlinePlus

    Hepatitis B is also known as serum hepatitis and is spread through blood and sexual contact. It is ... population. This photograph is an electronmicroscopic image of hepatitis B virus particles. (Image courtesy of the Centers for ...

  8. Avoiding Computer Viruses.

    ERIC Educational Resources Information Center

    Rowe, Joyce; And Others

    1989-01-01

    The threat of computer sabotage is a real concern to business teachers and others responsible for academic computer facilities. Teachers can minimize the possibility. Eight suggestions for avoiding computer viruses are given. (JOW)

  9. What's West Nile Virus?

    MedlinePlus

    ... is caused by a bite from an infected mosquito that's already carrying the virus, but it's important ... the risk of being bitten by an infected mosquito is greatest from July to early September. But ...

  10. Ebola virus disease

    MedlinePlus

    ... urine, saliva, sweat, feces, vomit, breast milk, and semen. The virus can enter the body through a ... use condoms for 12 months or until their semen has twice tested negative. Long-term complications can ...

  11. Simian hemorrhagic fever virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This book chapter describes the taxonomic classification of Simian hemorrhagic fever virus (SHFV). Included are: host, genome, classification, morphology, physicochemical and physical properties, nucleic acid, proteins, lipids, carbohydrates, geographic range, phylogenetic properties, biological pro...

  12. The dengue viruses.

    PubMed

    Henchal, E A; Putnak, J R

    1990-10-01

    Dengue, a major public health problem throughout subtropical and tropical regions, is an acute infectious disease characterized by biphasic fever, headache, pain in various parts of the body, prostration, rash, lymphadenopathy, and leukopenia. In more severe or complicated dengue, patients present with a severe febrile illness characterized by abnormalities of hemostasis and increased vascular permeability, which in some instances results in a hypovolemic shock. Four distinct serotypes of the dengue virus (dengue-1, dengue-2, dengue-3, and dengue-4) exist, with numerous virus strains found worldwide. Molecular cloning methods have led to a greater understanding of the structure of the RNA genome and definition of virus-specific structural and nonstructural proteins. Progress towards producing safe, effective dengue virus vaccines, a goal for over 45 years, has been made. PMID:2224837

  13. West Nile Virus

    MedlinePlus

    ... appeared in the United States in 1999. Infected mosquitoes spread the virus that causes it. People who ... barrels Stay indoors between dusk and dawn, when mosquitoes are most active Use screens on windows to ...

  14. The dengue viruses.

    PubMed Central

    Henchal, E A; Putnak, J R

    1990-01-01

    Dengue, a major public health problem throughout subtropical and tropical regions, is an acute infectious disease characterized by biphasic fever, headache, pain in various parts of the body, prostration, rash, lymphadenopathy, and leukopenia. In more severe or complicated dengue, patients present with a severe febrile illness characterized by abnormalities of hemostasis and increased vascular permeability, which in some instances results in a hypovolemic shock. Four distinct serotypes of the dengue virus (dengue-1, dengue-2, dengue-3, and dengue-4) exist, with numerous virus strains found worldwide. Molecular cloning methods have led to a greater understanding of the structure of the RNA genome and definition of virus-specific structural and nonstructural proteins. Progress towards producing safe, effective dengue virus vaccines, a goal for over 45 years, has been made. Images PMID:2224837

  15. Virus templated metallic nanoparticles

    NASA Astrophysics Data System (ADS)

    Aljabali, Alaa A. A.; Barclay, J. Elaine; Lomonossoff, George P.; Evans, David J.

    2010-12-01

    Plant viruses are considered as nanobuilding blocks that can be used as synthons or templates for novel materials. Cowpea mosaic virus (CPMV) particles have been shown to template the fabrication of metallic nanoparticles by an electroless deposition metallization process. Palladium ions were electrostatically bound to the virus capsid and, when reduced, acted as nucleation sites for the subsequent metal deposition from solution. The method, although simple, produced highly monodisperse metallic nanoparticles with a diameter of ca. <=35 nm. CPMV-templated particles were prepared with cobalt, nickel, iron, platinum, cobalt-platinum and nickel-iron.Plant viruses are considered as nanobuilding blocks that can be used as synthons or templates for novel materials. Cowpea mosaic virus (CPMV) particles have been shown to template the fabrication of metallic nanoparticles by an electroless deposition metallization process. Palladium ions were electrostatically bound to the virus capsid and, when reduced, acted as nucleation sites for the subsequent metal deposition from solution. The method, although simple, produced highly monodisperse metallic nanoparticles with a diameter of ca. <=35 nm. CPMV-templated particles were prepared with cobalt, nickel, iron, platinum, cobalt-platinum and nickel-iron. Electronic supplementary information (ESI) available: Additional experimental detail, agarose gel electrophoresis results, energy dispersive X-ray spectra, ζ-potential measurements, dynamic light scattering data, nanoparticle tracking analysis and an atomic force microscopy image of Ni-CPMV. See DOI: 10.1039/c0nr00525h

  16. Tick-borne viruses*

    PubMed Central

    Work, Telford H.

    1963-01-01

    More than 150 arthropod-borne viruses are now recognized, and over 50 of these are known to produce human infections and disease. Among these viruses are those of the tick-borne Russian spring-summer complex, which is etiologically involved in a wide variety of human diseases of varying severity. The eight antigenically different members of this complex so far known are Russian spring-summer encephalitis, louping-ill, Central European encephalitis, Omsk haemorrhagic fever, Kyasanur Forest disease, Langat, Negishi and Powassan viruses. In his review of the problems posed by these viruses and of research on them, the author points out that, while this complex is distributed around the globe in the temperate zone of the northern hemisphere, the only serious tick-borne virus disease known in the tropics is Kyasanur Forest disease. It is probable, however, that there are other, unrecognized tick-borne viruses in the tropical areas of Asia, Africa and America of importance to human health, and that these will be brought to light as virological studies of diseases of now obscure etiology are pursued. PMID:14043753

  17. Control of cucurbit viruses.

    PubMed

    Lecoq, Hervé; Katis, Nikolaos

    2014-01-01

    More than 70 well-characterized virus species transmitted by a diversity of vectors may infect cucurbit crops worldwide. Twenty of those cause severe epidemics in major production areas, occasionally leading to complete crop failures. Cucurbit viruses' control is based on three major axes: (i) planting healthy seeds or seedlings in a clean environment, (ii) interfering with vectors activity, and (iii) using resistant cultivars. Seed disinfection and seed or seedling quality controls guarantee growers on the sanitary status of their planting material. Removal of virus or vector sources in the crop environment can significantly delay the onset of viral epidemics. Insecticide or oil application may reduce virus spread in some situations. Diverse cultural practices interfere with or prevent vector reaching the crop. Resistance can be obtained by grafting for soil-borne viruses, by cross-protection, or generally by conventional breeding or genetic engineering. The diversity of the actions that may be taken to limit virus spread in cucurbit crops and their limits will be discussed. The ultimate goal is to provide farmers with technical packages that combine these methods within an integrated disease management program and are adapted to different countries and cropping systems. PMID:25410104

  18. Human Influenza Virus Infections.

    PubMed

    Peteranderl, Christin; Herold, Susanne; Schmoldt, Carole

    2016-08-01

    Seasonal and pandemic influenza are the two faces of respiratory infections caused by influenza viruses in humans. As seasonal influenza occurs on an annual basis, the circulating virus strains are closely monitored and a yearly updated vaccination is provided, especially to identified risk populations. Nonetheless, influenza virus infection may result in pneumonia and acute respiratory failure, frequently complicated by bacterial coinfection. Pandemics are, in contrary, unexpected rare events related to the emergence of a reassorted human-pathogenic influenza A virus (IAV) strains that often causes increased morbidity and spreads extremely rapidly in the immunologically naive human population, with huge clinical and economic impact. Accordingly, particular efforts are made to advance our knowledge on the disease biology and pathology and recent studies have brought new insights into IAV adaptation mechanisms to the human host, as well as into the key players in disease pathogenesis on the host side. Current antiviral strategies are only efficient at the early stages of the disease and are challenged by the genomic instability of the virus, highlighting the need for novel antiviral therapies targeting the pulmonary host response to improve viral clearance, reduce the risk of bacterial coinfection, and prevent or attenuate acute lung injury. This review article summarizes our current knowledge on the molecular basis of influenza infection and disease progression, the key players in pathogenesis driving severe disease and progression to lung failure, as well as available and envisioned prevention and treatment strategies against influenza virus infection. PMID:27486731

  19. Expression of blood group antigens H-2, Le(y), and sialylated-Le(a) in human colorectal carcinoma. An immunohistochemical study using double-labeling techniques.

    PubMed Central

    Cooper, H. S.; Malecha, M. J.; Bass, C.; Fagel, P. L.; Steplewski, Z.

    1991-01-01

    In this study, double-labeling immunohistochemistry was used to gain insight into the coexpression or interrelationship between blood group antigens (BGA) that are differentiation antigens in the normal colon, and BGA that are sequential moieties in the same synthetic pathway. Paired-wise Sialylated-Le(a)/Le(y) and H-2/Le(y) was studied. The Sialylated-Le(a) and Le(y) are synthesized from type 1 and type 2 backbones, respectively. In the normal colon, the Le(y) and Sialylated-Le(a) are expressed by cells at the base and surface of the crypt, respectively, representing undifferentiated and differentiated enterocytes. The H-2 is considered oncofetal in nature, and is considered to be the immediate precursor in the synthesis of Le(y). In individual cancers. Sialylated-Lea and Le(y) were detected in different cancer cells within the same malignant glands, separately in different glands, and in different subcellular compartments of the same cell. Both H-2 and Le(y) were coexpressed in the same individual cells in 92% of cancers expressing both these BGA. In 50% of the cancers, the H-2 and Le(y) also were expressed separately in different malignant glands within individual tumors. These findings indicate that, in colorectal cancers, differentiation antigens (Sialylated Le(a) and Le(y)) are expressed by different individual cells within the same malignant gland somewhat, recapitulating the normal colon crypt. Antigens of different backbones occasionally may be expressed in the same cells but within different subcellular compartments. Precursor accumulation is common in cancers, and antigens in the same synthetic pathway are coexpressed in the same cell. The expression of H-2 and Le(y) in different glands (lack of coexpression) may be explained possibly by aberrant synthesis of Le(y) by an alternate pathway. Images Figure 1 PMID:1987759

  20. Transmission of influenza A viruses.

    PubMed

    Neumann, Gabriele; Kawaoka, Yoshihiro

    2015-05-01

    Influenza A viruses cause respiratory infections that range from asymptomatic to deadly in humans. Widespread outbreaks (pandemics) are attributable to 'novel' viruses that possess a viral hemagglutinin (HA) gene to which humans lack immunity. After a pandemic, these novel viruses form stable virus lineages in humans and circulate until they are replaced by other novel viruses. The factors and mechanisms that facilitate virus transmission among hosts and the establishment of novel lineages are not completely understood, but the HA and basic polymerase 2 (PB2) proteins are thought to play essential roles in these processes by enabling avian influenza viruses to infect mammals and replicate efficiently in their new host. Here, we summarize our current knowledge of the contributions of HA, PB2, and other viral components to virus transmission and the formation of new virus lineages. PMID:25812763

  1. Transmission of Influenza A Viruses

    PubMed Central

    Neumann, Gabriele; Kawaoka, Yoshihiro

    2015-01-01

    Influenza A viruses cause respiratory infections that range from asymptomatic to deadly in humans. Widespread outbreaks (pandemics) are attributable to ‘novel’ viruses that possess a viral hemagglutinin (HA) gene to which humans lack immunity. After a pandemic, these novel viruses form stable virus lineages in humans and circulate until they are replaced by other novel viruses. The factors and mechanisms that facilitate virus transmission among hosts and the establishment of novel lineages are not completely understood, but the HA and basic polymerase 2 (PB2) proteins are thought to play essential roles in these processes by enabling avian influenza viruses to infect mammals and replicate efficiently in their new host. Here, we summarize our current knowledge of the contributions of HA, PB2, and other viral components to virus transmission and the formation of new virus lineages. PMID:25812763

  2. Smaller Fleas: Viruses of Microorganisms

    PubMed Central

    Hyman, Paul; Abedon, Stephen T.

    2012-01-01

    Life forms can be roughly differentiated into those that are microscopic versus those that are not as well as those that are multicellular and those that, instead, are unicellular. Cellular organisms seem generally able to host viruses, and this propensity carries over to those that are both microscopic and less than truly multicellular. These viruses of microorganisms, or VoMs, in fact exist as the world's most abundant somewhat autonomous genetic entities and include the viruses of domain Bacteria (bacteriophages), the viruses of domain Archaea (archaeal viruses), the viruses of protists, the viruses of microscopic fungi such as yeasts (mycoviruses), and even the viruses of other viruses (satellite viruses). In this paper we provide an introduction to the concept of viruses of microorganisms, a.k.a., viruses of microbes. We provide broad discussion particularly of VoM diversity. VoM diversity currently spans, in total, at least three-dozen virus families. This is roughly ten families per category—bacterial, archaeal, fungal, and protist—with some virus families infecting more than one of these microorganism major taxa. Such estimations, however, will vary with further discovery and taxon assignment and also are dependent upon what forms of life one includes among microorganisms. PMID:24278736

  3. Trigeminocardiac reflex and haemodynamic changes during Le Fort I osteotomy.

    PubMed

    Kiani, M T; Tajik, G; Ajami, M; Fazli, H; Kharazifard, M J; Mesgarzadeh, A

    2016-05-01

    The Le Fort I osteotomy is performed under general anaesthesia and specific haemodynamic conditions, i.e. hypotensive general anaesthesia. This study assessed the incidence of the trigeminocardiac reflex (TCR) during the different stages of the Le Fort I osteotomy. Forty-seven patients requiring a Le Fort I osteotomy were included. General anaesthesia was induced. In terms of haemodynamic changes, each patient's oxygen saturation (SpO2), mean arterial pressure (MAP), heart rate (HR), and electrocardiogram (ECG) were monitored by SADAAT Monitoring System and recorded during the different stages of osteotomy: before the induction of anaesthesia, before osteotomy cuts, after finishing the right pterygoid plate osteotomy, after finishing the left pterygoid plate osteotomy, and after performing down-fracture of the maxilla. No significant alteration in haemodynamic values was seen at the different stages of Le Fort I osteotomy. One patient showed arrhythmia with non-sinus junction rhythm after sinus bradycardia and two premature atrial contractions in the down-fracture stage, which led to the abrupt cessation of the procedure by the surgeon. This study showed no significant alterations in haemodynamic values during the different stages of Le Fort I osteotomy. Halting the procedure momentarily was sufficient to allow spontaneous normalization of the HR, blood pressure, and dysrhythmia. PMID:26794400

  4. Developpement et application d'un systeme mobile de laser terrestre pour quantifier le bilan sedimentaire des plages

    NASA Astrophysics Data System (ADS)

    Van-Wierts, Stefanie

    Au Québec maritime, l'érosion côtière est une problématique d'envergure, notamment sur les côtes de formations meubles. Les plages ont un rôle de zone tampon ayant comme fonction naturelle d'absorber l'énergie des vagues et donc d'assurer l'équilibre de certains écosystèmes et le maintien de l'écoumène en réduisant l'érosion de la côte. Les méthodes d'acquisition conventionnelles ne permettent pas de quantifier convenablement les changements morphosédimentaires d'une plage à l'échelle des cellules hydrosédimentaires. Le manque de méthode d'acquisition fiable et de données quantitatives mène à une surestimation ou à une sous-estimation de la disponibilité sédimentaire d'un système côtier. Pour contrer ces lacunes et afin de minimiser les coûts d'acquisition, un nouveau système mobile de LiDAR terrestre a été mis en place, permettant d'acquérir des données topographiques de l'estran, de la haute plage et des falaises. Le système multicapteurs comprend un LiDAR, un système de navigation à haute précision (IMU et D-GPS) et une caméra. L'ensemble des instruments et capteurs sont montés sur un véhicule de type tout-terrain. Le système a été évalué sur la zone côtière de la péninsule de Manicouagan. La comparaison des données LiDAR avec 1 050 points de référence géopositionnés au D-GPS montre une erreur verticale moyenne de 0,1 m sur les secteurs de plage. Les résultats montrent que le volume sédimentaire moyen des plages devant les zones où la ligne de rivage présente un ouvrage de protection en enrochement (12 m 3/m) est plus de trois fois plus faible que devant les secteurs à l'état naturel (35,5 m3/m). La moyenne des secteurs en transition, constituant les segments où une zone artificielle et une zone naturelle se chevauchent présentent un volume moyen de 28 m3/m. Aussi, les plages devant les secteurs anthropisés sont en moyenne près de 2 fois plus étroites (12,7 m) que devant les secteurs naturels (25

  5. [Zika virus infection during pregnancy].

    PubMed

    Picone, O; Vauloup-Fellous, C; D'Ortenzio, E; Huissoud, C; Carles, G; Benachi, A; Faye, A; Luton, D; Paty, M-C; Ayoubi, J-M; Yazdanpanah, Y; Mandelbrot, L; Matheron, S

    2016-05-01

    A Zika virus epidemic is currently ongoing in the Americas. This virus is linked to congenital infections with potential severe neurodevelopmental dysfunction. However, incidence of fetal infection and whether this virus is responsible of other fetal complications are still unknown. National and international public health authorities recommend caution and several prevention measures. Declaration of Zika virus infection is now mandatory in France. Given the available knowledge on Zika virus, we suggest here a review of the current recommendations for management of pregnancy in case of suspicious or infection by Zika virus in a pregnant woman. PMID:27079865

  6. Le lipome para testiculaire: à propos d'un cas rare

    PubMed Central

    Lasri, Abdelouahed; Lamchahab, Hamza; Lahyani, Mounir; Karmouni, Tarik; Elkhader, Khalid; Koutani, Abdellatif; Andaloussi, Ahmed Ibn Attya

    2015-01-01

    Les tumeurs para testiculaires sont des tumeurs rares et complexes qui ont une symptomatologie insidieuse et pauvre. Les formes bénignes représentent 70%. Le lipome para testiculaire étant le type le plus fréquent. L'examen clinique est peu spécifique. L'examen échographique est la pierre angulaire pour assoir le diagnostic. Le traitement chirurgical s'impose en cas de tumeur symptomatique, l'histologie étant habituellement typique permet la confirmation diagnostique. Le pronostic est bon malgré d’éventuelles récidives. PMID:26175802

  7. L’évaluation d'un programme d’éducation thérapeutique chez le patient diabétique dans un Centre Hospitalier Universitaire marocain: résultats préliminaires d'une enquête pilote

    PubMed Central

    Doubi, Sana; El Ouahabi, Hanan; Dakkar, Otmane; Ajdi, Farida

    2014-01-01

    L’éducation thérapeutique est fondamentale. Elle n'a pas uniquement pour effet la préservation du capital de santé par le meilleur contrôle métabolique, favorisé par la responsabilisation et l'autonomie. En effet, en se soignant mieux, le diabétique peut améliorer sa qualité de vie, et en retirer un bénéfice qui va au-delà de la satisfaction de préserver son avenir. L'objectif principal de cette étude était de déterminer le nombre des patients diabétiques ayant bénéficié d'une éducation thérapeutique, la relation entre cette éducation et les paramètres sociodémographiques de la population étudiée et clinico-biologiques liées à la maladie. Nous avions réalisé une étude transversale, étalée sur 3 mois, intéressant 100 patients diabétiques suivis au service d'Endocrinologie au CHU Hassan II Fès. L’âge moyen des patients était de 50,01 ans +/-16,44; 60% des patients étaient des femmes, la majorité des patients étaient des diabétiques de type2 (81 malades). La majorité des patients avaient un niveau d'instruction bas (41% non scolarisés), 69% appartenaient au milieu urbain. Alors que 62 malades n'avaient pas de couverture sociale. L’éducation thérapeutique avait compris différents thèmes: 91% des patients avaient bénéficié d'une éducation sur les mesures hygiéno-diététiques (néanmoins 34% ne les respectaient pas); 98% sur l'auto mesure glycémique (cependant 28% des patients ne surveillaient pas leurs glycémies régulièrement); 59% sur l'intérêt de HbA1c; 79% sur les complications du diabète et la majorité des patients avaient bénéficié d'une éducation sur le traitement antidiabétique (80%). L'analyse des données a mis en évidence une relation statiquement significative entre le niveau socioéconomique, le niveau d’éducation, le milieu de vie et l'application des différents volés de l’éducation thérapeutique: les mesures hygiéno-diététiques, le suivi médical et l'observance du

  8. Pterygoid Plate Fractures: Not Limited to Le Fort Fractures.

    PubMed

    Garg, Ravi K; Alsheik, Nila H; Afifi, Ahmed M; Gentry, Lindell R

    2015-09-01

    Pterygoid plate fractures are often described in the setting of Le Fort fractures. The goal of this study was to define other craniofacial fracture patterns causing injury to the pterygoid plates. A retrospective review of computed tomography (CT) scans obtained on craniofacial trauma patients over a 5-year period revealed 209 patients with pterygoid plate fractures. Pterygoid plate fractures in 78 patients (37.3%) were unrelated to Le Fort fractures. Common causes included sphenotemporal buttress fractures in 26 patients (33.3%), temporal bone fractures in 18 patients (23.1%), zygomaticomaxillary complex fractures in 17 patients (21.8%), and displaced mandible fractures in 14 patients (17.9%). These findings indicate that approximately one third of pterygoid plate fractures do not result from Le Fort pattern injuries and that the craniofacial surgeon should have a broad differential for causes of pterygoid plate fractures when reviewing trauma imaging. PMID:26147022

  9. [Serodiagnosis of toxoplasmosis: a comparative multicenter study of a standard scale through various actual tests and expression of the results in international units. Groupe de travail toxoplasmose du Contrôle national de qualité en parasotologie. Syndicat des fabricants de réactifs de laboratoire. Groupe de travail standardisation des tests sérologiques du Réseau européen de lutte contre la toxoplasmose congénitale].

    PubMed

    Petithory, J C; Ambroise-Thomas, P; De Loye, J; Pelloux, H; Goullier-Fleuret, A; Milgram, M; Buffard, C; Garin, J P

    1996-01-01

    Reported are the results of a multicentre study involving 40 laboratories that was carried out in France to assess all the currently available methods used for the serodiagnosis of toxoplasmosis. For this purpose 10 batches of control sera were prepared with titres in the range 0-260 IU per ml. These sera were tested in nine laboratories using immunofluorescence methods; in three laboratories using dye tests; in forty laboratories using enzyme-linked immunosorbent assay; in four laboratories using direct agglutination and haemagglutination; in seven laboratories using the high-sensitivity IgG agglutination test; and in three laboratories using the latex agglutination test. In this way, 70 series of titrations were carried out using seven procedures and the results were compared with those obtained using the WHO reference serum in 15 cases, with the French national E6 serum in 16 other cases, and in 39 cases using 15 reference sera supplied by the reagent manufacturers. Rigorous comparison of the tests was not possible in all cases because one aim of the study was to ensure that the tests were carried out under the usual working conditions that prevailed in the participating laboratories. The results obtained indicate that the serological tests currently available for toxoplasmosis are acceptable for its serodiagnosis. Presentation of the titres in IU has advantages; however, caution is required since the definition of IU varies according to the test and reagents used. It is therefore essential that the conditions and limits for a positive reaction be carefully defined in each case, especially for commercially available kits. PMID:8829878

  10. Recombinant Vaccinia Virus: Immunization against Multiple Pathogens

    NASA Astrophysics Data System (ADS)

    Perkus, Marion E.; Piccini, Antonia; Lipinskas, Bernard R.; Paoletti, Enzo

    1985-09-01

    The coding sequences for the hepatitis B virus surface antigen, the herpes simplex virus glycoprotein D, and the influenza virus hemagglutinin were inserted into a single vaccinia virus genome. Rabbits inoculated intravenously or intradermally with this polyvalent vaccinia virus recombinant produced antibodies reactive to all three authentic foreign antigens. In addition, the feasibility of multiple rounds of vaccination with recombinant vaccinia virus was demonstrated.

  11. Viruses and Multiple Sclerosis

    PubMed Central

    Owens, Gregory P.; Gilden, Don; Burgoon, Mark P.; Yu, Xiaoli; Bennett, Jeffrey L.

    2012-01-01

    Multiple sclerosis (MS) is a chronic demyelinating disorder of unknown etiology, possibly caused by a virus or virus-triggered immunopathology. The virus might reactivate after years of latency and lyse oligodendrocytes, as in progressive multifocal leukoencephalopathy, or initiate immunopathological demyelination, as in animals infected with Theiler’s murine encephalomyelitis virus or coronaviruses. The argument for a viral cause of MS is supported by epidemiological analyses and studies of MS in identical twins, indicating that disease is acquired. However, the most important evidence is the presence of bands of oligoclonal IgG (OCBs) in MS brain and CSF that persist throughout the lifetime of the patient. OCBs are found almost exclusively in infectious CNS disorders, and antigenic targets of OCBs represent the agent that causes disease. Here, the authors review past attempts to identify an infectious agent in MS brain cells and discuss the promise of using recombinant antibodies generated from clonally expanded plasma cells in brain and CSF to identify disease-relevant antigens. They show how this strategy has been used successfully to analyze antigen specificity in subacute sclerosing panencephalitis, a chronic encephalitis caused by measles virus, and in neuromyelitis optica, a chronic autoimmune demyelinating disease produced by antibodies directed against the aquaporin-4 water channel. PMID:22130640

  12. Nongenital herpes simplex virus.

    PubMed

    Usatine, Richard P; Tinitigan, Rochelle

    2010-11-01

    Nongenital herpes simplex virus type 1 is a common infection usually transmitted during childhood via nonsexual contact. Most of these infections involve the oral mucosa or lips (herpes labialis). The diagnosis of an infection with herpes simplex virus type 1 is usually made by the appearance of the lesions (grouped vesicles or ulcers on an erythematous base) and patient history. However, if uncertain, the diagnosis of herpes labialis can be made by viral culture, polymerase chain reaction, serology, direct fluorescent antibody testing, or Tzanck test. Other nonoral herpes simplex virus type 1 infections include herpetic keratitis, herpetic whitlow, herpes gladiatorum, and herpetic sycosis of the beard area. The differential diagnosis of nongenital herpes simplex virus infection includes aphthous ulcers, acute paronychia, varicella-zoster virus infection, herpangina, herpes gestationis (pemphigoid gestationis), pemphigus vulgaris, and Behçet syndrome. Oral acyclovir suspension is an effective treatment for children with primary herpetic gingivostomatitis. Oral acyclovir, valacyclovir, and famciclovir are effective in treating acute recurrence of herpes labialis (cold sores). Recurrences of herpes labialis may be diminished with daily oral acyclovir or valacyclovir. Topical acyclovir, penciclovir, and docosanol are optional treatments for recurrent herpes labialis, but they are less effective than oral treatment. PMID:21121552

  13. Respiratory syncytial virus bronchiolitis.

    PubMed Central

    Leung, Alexander K. C.; Kellner, James D.; Davies, H. Dele

    2005-01-01

    Respiratory syncytial virus, the most common cause of bronchiolitis, is the leading cause of infant hospitalization in developed countries and accounts for substantial mortality and morbidity in developing countries. Children at increased risk of developing severe bronchiolitis are those <6 weeks of age, those born prematurely and those with an underlying cardiopulmonary disorder or immunodeficiency. Approximately 80% of cases occur in the first year of life. By two years of age, virtually all children have been infected by at least one strain of the virus. Classically, respiratory syncytial virus bronchiolitis manifests as cough, wheezing and respiratory distress. The mainstay of treatment is supportive care, consisting of adequate fluid intake, antipyretics to control fever and use of supplemental oxygen if necessary. Frequent and meticulous hand-washing is the best measure to prevent secondary spread. Treatment of respiratory syncytial virus bronchiolitis beyond supportive care should be individualized. Palivizumab has been shown to be effective in preventing severe respiratory syncytial virus bronchiolitis in high-risk children when given prophylactically. In the majority of cases, the disease is usually self-limited. The mortality rate is <1% and occurs predominantly in children at high risk for severe disease. PMID:16396064

  14. Viruses and multiple sclerosis.

    PubMed

    Owens, Gregory P; Gilden, Don; Burgoon, Mark P; Yu, Xiaoli; Bennett, Jeffrey L

    2011-12-01

    Multiple sclerosis (MS) is a chronic demyelinating disorder of unknown etiology, possibly caused by a virus or virus-triggered immunopathology. The virus might reactivate after years of latency and lyse oligodendrocytes, as in progressive multifocal leukoencephalopathy, or initiate immunopathological demyelination, as in animals infected with Theiler's murine encephalomyelitis virus or coronaviruses. The argument for a viral cause of MS is supported by epidemiological analyses and studies of MS in identical twins, indicating that disease is acquired. However, the most important evidence is the presence of bands of oligoclonal IgG (OCBs) in MS brain and CSF that persist throughout the lifetime of the patient. OCBs are found almost exclusively in infectious CNS disorders, and antigenic targets of OCBs represent the agent that causes disease. Here, the authors review past attempts to identify an infectious agent in MS brain cells and discuss the promise of using recombinant antibodies generated from clonally expanded plasma cells in brain and CSF to identify disease-relevant antigens. They show how this strategy has been used successfully to analyze antigen specificity in subacute sclerosing panencephalitis, a chronic encephalitis caused by measles virus, and in neuromyelitis optica, a chronic autoimmune demyelinating disease produced by antibodies directed against the aquaporin-4 water channel. PMID:22130640

  15. Attenuation of Vaccinia Virus.

    PubMed

    Yakubitskiy, S N; Kolosova, I V; Maksyutov, R A; Shchelkunov, S N

    2015-01-01

    Since 1980, in the post-smallpox vaccination era the human population has become increasingly susceptible compared to a generation ago to not only the variola (smallpox) virus, but also other zoonotic orthopoxviruses. The need for safer vaccines against orthopoxviruses is even greater now. The Lister vaccine strain (LIVP) of vaccinia virus was used as a parental virus for generating a recombinant 1421ABJCN clone defective in five virulence genes encoding hemagglutinin (A56R), the IFN-γ-binding protein (B8R), thymidine kinase (J2R), the complement-binding protein (C3L), and the Bcl-2-like inhibitor of apoptosis (N1L). We found that disruption of these loci does not affect replication in mammalian cell cultures. The isogenic recombinant strain 1421ABJCN exhibits a reduced inflammatory response and attenuated neurovirulence relative to LIVP. Virus titers of 1421ABJCN were 3 lg lower versus the parent VACV LIVP when administered by the intracerebral route in new-born mice. In a subcutaneous mouse model, 1421ABJCN displayed levels of VACV-neutralizing antibodies comparable to those of LIVP and conferred protective immunity against lethal challenge by the ectromelia virus. The VACV mutant holds promise as a safe live vaccine strain for preventing smallpox and other orthopoxvirus infections. PMID:26798498

  16. The pathogenic role of virus-specific antibody-secreting cells in the central nervous system of rats with different susceptibility to coronavirus-induced demyelinating encephalitis.

    PubMed Central

    Schwender, S; Imrich, H; Dörries, R

    1991-01-01

    The humoral immune response in the central nervous system (CNS) of susceptible Lewis (LE) rats and resistant Brown Norway (BN) rats was analysed after intracerebral infection with the murine coronavirus JHM (MHV4). The subclinical course of the infection in BN rats was characterized by an early rise of neutralizing antibodies in the cerebrospinal fluid (CSF) 7 days post-infection. At this time in LE rats, neutralizing antibodies were not detectable in the CSF and the animals developed neurological signs of infection. Subsequently, LE rats recovered from disease. This process was accompanied by increasing titres of virus-neutralizing antibodies. Within the CNS parenchyma of both rat strains, equivalent numbers of IgM-secreting cells were detected. However, in BN rats, virus-specific IgG secreting cells appeared earlier and in higher numbers. Moreover, based on the size of zones of antibody secreted by single cells in the Spot-ELISA assay, it appeared that cells from BN rats secreted IgG antibody of higher affinity. These data suggest that early maturation of antiviral antibody responses in the resistant BN rat probably restricts the spread of viral infection to small foci within the CNS, resulting in a subclinical level of primary demyelination. In contrast, the absence of neutralizing antibodies in the susceptible LE rats favours spread of the virus throughout the CNS, resulting finally in severe neurological disease. Images Figure 1 Figure 2 Figure 3 PMID:1663078

  17. Production of virus resistant plants

    DOEpatents

    Dougherty, W.G.; Lindbo, J.A.

    1996-12-10

    A method of suppressing virus gene expression in plants using untranslatable plus sense RNA is disclosed. The method is useful for the production of plants that are resistant to virus infection. 9 figs.

  18. Testing for Human Immunodeficiency Virus

    MedlinePlus

    ... incisions made in the mother’s abdomen and uterus. Human Immunodeficiency Virus (HIV): A virus that attacks certain cells of the body’s immune system and causes acquired immunodeficiency syndrome (AIDS). Immune System: ...

  19. Special Issue: Honey Bee Viruses

    PubMed Central

    Gisder, Sebastian; Genersch, Elke

    2015-01-01

    Pollination of flowering plants is an important ecosystem service provided by wild insect pollinators and managed honey bees. Hence, losses and declines of pollinating insect species threaten human food security and are of major concern not only for apiculture or agriculture but for human society in general. Honey bee colony losses and bumblebee declines have attracted intensive research interest over the last decade and although the problem is far from being solved we now know that viruses are among the key players of many of these bee losses and bumblebee declines. With this special issue on bee viruses we, therefore, aimed to collect high quality original papers reflecting the current state of bee virus research. To this end, we focused on newly discovered viruses (Lake Sinai viruses, bee macula-like virus), or a so far neglected virus species (Apis mellifera filamentous virus), and cutting edge technologies (mass spectrometry, RNAi approach) applied in the field. PMID:26702462

  20. Chlorella viruses isolated in China

    SciTech Connect

    Zhang, Y.; Burbank, D.E.; Van Etten, J.L. )

    1988-09-01

    Plaque-forming viruses of the unicellular, eukaryotic, exsymbiotic, Chlorella-like green algae strain NC64A, which are common in the United States, were also present in fresh water collected in the People's Republic of China. Seven of the Chinese viruses were examined in detail and compared with the Chlorella viruses previously isolated in the United States. Like the American viruses, the Chinese viruses were large polyhedra and sensitive to chloroform. They contained numerous structural proteins and large double-stranded DNA genomes of at least 300 kilobase pairs. Each of the DNAs from the Chinese viruses contained 5-methyldeoxycytosine, which varied from 12.6 to 46.7% of the deoxycytosine, and N{sup 6}-methyldeoxyadenosine, which varied from 2.2 to 28.3% of the deoxyadenosine. Four of the Chinese virus DNAs hybridized extensively with {sup 32}P-labeled DNA from the American virus PBCV-1, and three hybridized poorly.

  1. Epstein-Barr virus test

    MedlinePlus

    ... medlineplus.gov/ency/article/003513.htm Epstein-Barr virus antibody test To use the sharing features on this page, please enable JavaScript. Epstein-Barr virus antibody test is a blood test to detect ...

  2. Ebola (Ebola Virus Disease): Prevention

    MedlinePlus

    ... Search The CDC Cancel Submit Search The CDC Ebola (Ebola Virus Disease) Note: Javascript is disabled or is ... message, please visit this page: About CDC.gov . Ebola (Ebola Virus Disease) About Ebola Questions & Answers 2014 ...

  3. Ebola (Ebola Virus Disease): Transmission

    MedlinePlus

    ... Search The CDC Cancel Submit Search The CDC Ebola (Ebola Virus Disease) Note: Javascript is disabled or is ... message, please visit this page: About CDC.gov . Ebola (Ebola Virus Disease) About Ebola Questions & Answers 2014 ...

  4. Ebola (Ebola Virus Disease): Treatment

    MedlinePlus

    ... Search The CDC Cancel Submit Search The CDC Ebola (Ebola Virus Disease) Note: Javascript is disabled or is ... message, please visit this page: About CDC.gov . Ebola (Ebola Virus Disease) About Ebola Questions & Answers 2014 ...

  5. Ebola (Ebola Virus Disease): Diagnosis

    MedlinePlus

    ... Search The CDC Cancel Submit Search The CDC Ebola (Ebola Virus Disease) Note: Javascript is disabled or is ... message, please visit this page: About CDC.gov . Ebola (Ebola Virus Disease) About Ebola Questions & Answers 2014 ...

  6. Oncolytic viruses: finally delivering

    PubMed Central

    Seymour, Leonard W; Fisher, Kerry D

    2016-01-01

    Oncolytic viruses can be found at the confluence of virology, genetic engineering and pharmacology where versatile platforms for molecularly targeted anticancer agents can be designed and optimised. Oncolytic viruses offer several important advantages over traditional approaches, including the following. (1) Amplification of the active agent (infectious virus particles) within the tumour. This avoids unnecessary exposure to normal tissues experienced during delivery of traditional stoichiometric chemotherapy and maximises the therapeutic index. (2) The active cell-killing mechanisms, often independent of programmed death mechanisms, should decrease the emergence of acquired drug resistance. (3) Lytic death of cancer cells provides a pro-inflammatory microenvironment and the potential for induction of an anticancer vaccine response. (4) Tumour-selective expression and secretion of encoded anticancer biologics, providing a new realm of potent and cost-effective-targeted therapeutics. PMID:26766734

  7. Oncolytic viruses: finally delivering.

    PubMed

    Seymour, Leonard W; Fisher, Kerry D

    2016-02-16

    Oncolytic viruses can be found at the confluence of virology, genetic engineering and pharmacology where versatile platforms for molecularly targeted anticancer agents can be designed and optimised. Oncolytic viruses offer several important advantages over traditional approaches, including the following. (1) Amplification of the active agent (infectious virus particles) within the tumour. This avoids unnecessary exposure to normal tissues experienced during delivery of traditional stoichiometric chemotherapy and maximises the therapeutic index. (2) The active cell-killing mechanisms, often independent of programmed death mechanisms, should decrease the emergence of acquired drug resistance. (3) Lytic death of cancer cells provides a pro-inflammatory microenvironment and the potential for induction of an anticancer vaccine response. (4) Tumour-selective expression and secretion of encoded anticancer biologics, providing a new realm of potent and cost-effective-targeted therapeutics. PMID:26766734

  8. Pathobiology of avian influenza viruses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Avian influenza virus causes serious disease in a wide variety of birds and mammals. Its natural hosts are wild aquatic birds, in which most infections are unapparent. Avian Influenza (AI) viruses are classified into 16 hemagglutinin (H1-16) and nine neuraminidase (N1-9) subtypes. Each virus has on...

  9. Detection of Lassa Virus, Mali

    PubMed Central

    Safronetz, David; Lopez, Job E.; Sogoba, Nafomon; Traore’, Sékou F.; Raffel, Sandra J.; Fischer, Elizabeth R.; Ebihara, Hideki; Branco, Luis; Garry, Robert F.; Schwan, Tom G.

    2010-01-01

    To determine whether Lassa virus was circulating in southern Mali, we tested samples from small mammals from 3 villages, including Soromba, where in 2009 a British citizen probably contracted a lethal Lassa virus infection. We report the isolation and genetic characterization of Lassa virus from an area previously unknown for Lassa fever. PMID:20587185

  10. Protecting Your Computer from Viruses

    ERIC Educational Resources Information Center

    Descy, Don E.

    2006-01-01

    A computer virus is defined as a software program capable of reproducing itself and usually capable of causing great harm to files or other programs on the same computer. The existence of computer viruses--or the necessity of avoiding viruses--is part of using a computer. With the advent of the Internet, the door was opened wide for these…

  11. Avian influenza virus RNA extraction

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The efficient extraction and purification of viral RNA is critical for down-stream molecular applications whether it is the sensitive and specific detection of virus in clinical samples, virus gene cloning and expression, or quantification of avian influenza (AI) virus by molecular methods from expe...

  12. Computer Bytes, Viruses and Vaccines.

    ERIC Educational Resources Information Center

    Palmore, Teddy B.

    1989-01-01

    Presents a history of computer viruses, explains various types of viruses and how they affect software or computer operating systems, and describes examples of specific viruses. Available vaccines are explained, and precautions for protecting programs and disks are given. (nine references) (LRW)

  13. Ipomoviruses: Squash vein yellowing virus, Cucumber vein yellowing virus, Cassava brown streak virus, and Ugandan cassava brown streak virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ipomoviruses including Squash vein yellowing virus, Cucumber vein yellowing virus and Cassava brown streak virus are currently causing significant economic impact on crop production in several regions of the world. Only recently have results of detailed characterization of their whitefly transmissi...

  14. An introduction to computer viruses

    SciTech Connect

    Brown, D.R.

    1992-03-01

    This report on computer viruses is based upon a thesis written for the Master of Science degree in Computer Science from the University of Tennessee in December 1989 by David R. Brown. This thesis is entitled An Analysis of Computer Virus Construction, Proliferation, and Control and is available through the University of Tennessee Library. This paper contains an overview of the computer virus arena that can help the reader to evaluate the threat that computer viruses pose. The extent of this threat can only be determined by evaluating many different factors. These factors include the relative ease with which a computer virus can be written, the motivation involved in writing a computer virus, the damage and overhead incurred by infected systems, and the legal implications of computer viruses, among others. Based upon the research, the development of a computer virus seems to require more persistence than technical expertise. This is a frightening proclamation to the computing community. The education of computer professionals to the dangers that viruses pose to the welfare of the computing industry as a whole is stressed as a means of inhibiting the current proliferation of computer virus programs. Recommendations are made to assist computer users in preventing infection by computer viruses. These recommendations support solid general computer security practices as a means of combating computer viruses.

  15. Hendra virus and Nipah virus animal vaccines.

    PubMed

    Broder, Christopher C; Weir, Dawn L; Reid, Peter A

    2016-06-24

    Hendra virus (HeV) and Nipah virus (NiV) are zoonotic viruses that emerged in the mid to late 1990s causing disease outbreaks in livestock and people. HeV appeared in Queensland, Australia in 1994 causing a severe respiratory disease in horses along with a human case fatality. NiV emerged a few years later in Malaysia and Singapore in 1998-1999 causing a large outbreak of encephalitis with high mortality in people and also respiratory disease in pigs which served as amplifying hosts. The key pathological elements of HeV and NiV infection in several species of mammals, and also in people, are a severe systemic and often fatal neurologic and/or respiratory disease. In people, both HeV and NiV are also capable of causing relapsed encephalitis following recovery from an acute infection. The known reservoir hosts of HeV and NiV are several species of pteropid fruit bats. Spillovers of HeV into horses continue to occur in Australia and NiV has caused outbreaks in people in Bangladesh and India nearly annually since 2001, making HeV and NiV important transboundary biological threats. NiV in particular possesses several features that underscore its potential as a pandemic threat, including its ability to infect humans directly from natural reservoirs or indirectly from other susceptible animals, along with a capacity of limited human-to-human transmission. Several HeV and NiV animal challenge models have been developed which have facilitated an understanding of pathogenesis and allowed for the successful development of both active and passive immunization countermeasures. PMID:27154393

  16. Ecology of prokaryotic viruses.

    PubMed

    Weinbauer, Markus G

    2004-05-01

    The finding that total viral abundance is higher than total prokaryotic abundance and that a significant fraction of the prokaryotic community is infected with phages in aquatic systems has stimulated research on the ecology of prokaryotic viruses and their role in ecosystems. This review treats the ecology of prokaryotic viruses ('phages') in marine, freshwater and soil systems from a 'virus point of view'. The abundance of viruses varies strongly in different environments and is related to bacterial abundance or activity suggesting that the majority of the viruses found in the environment are typically phages. Data on phage diversity are sparse but indicate that phages are extremely diverse in natural systems. Lytic phages are predators of prokaryotes, whereas lysogenic and chronic infections represent a parasitic interaction. Some forms of lysogeny might be described best as mutualism. The little existing ecological data on phage populations indicate a large variety of environmental niches and survival strategies. The host cell is the main resource for phages and the resource quality, i.e., the metabolic state of the host cell, is a critical factor in all steps of the phage life cycle. Virus-induced mortality of prokaryotes varies strongly on a temporal and spatial scale and shows that phages can be important predators of bacterioplankton. This mortality and the release of cell lysis products into the environment can strongly influence microbial food web processes and biogeochemical cycles. Phages can also affect host diversity, e.g., by 'killing the winner' and keeping in check competitively dominant species or populations. Moreover, they mediate gene transfer between prokaryotes, but this remains largely unknown in the environment. Genomics or proteomics are providing us now with powerful tools in phage ecology, but final testing will have to be performed in the environment. PMID:15109783

  17. Relationship of lychnis ringspot virus to barley stripe mosaic virus and poa semilatent virus.

    PubMed

    Hunter, B G; Smith, J; Fattouh, F; Jackson, A O

    1989-01-01

    Barley stripe mosaic virus (BSMV), poa semilatent virus (PSLV), and lychnis ringspot virus (LRSV) have previously been assigned to the hordeivirus group because of similarities in their particle morphology, physicochemical properties and serological analyses. However, the serological relationships of the three viruses have not been determined by direct comparison. The present study evaluated the relatedness of these viruses by Western and dot immunoblotting and by nucleic acid hybridizations. Serological analyses of the coat proteins separated by gel electrophoresis and of intact virus particles bound to nitrocellulose membranes revealed that BSMV and PSLV are distantly related, but that they are more closely related to each other than to LRSV. The genomic RNAs of the viruses failed to cross-hybridize in northern hybridization tests conducted at different temperatures. These comparisons showed that BSMV, PSLV and LRSV are distinct viruses with little nucleotide sequence relatedness. Thus our data provide additional support for their inclusion as separate members of the hordeivirus group. PMID:2722469

  18. Research on computer virus database management system

    NASA Astrophysics Data System (ADS)

    Qi, Guoquan

    2011-12-01

    The growing proliferation of computer viruses becomes the lethal threat and research focus of the security of network information. While new virus is emerging, the number of viruses is growing, virus classification increasing complex. Virus naming because of agencies' capture time differences can not be unified. Although each agency has its own virus database, the communication between each other lacks, or virus information is incomplete, or a small number of sample information. This paper introduces the current construction status of the virus database at home and abroad, analyzes how to standardize and complete description of virus characteristics, and then gives the information integrity, storage security and manageable computer virus database design scheme.

  19. Zika Virus Outside Africa

    PubMed Central

    2009-01-01

    Zika virus (ZIKV) is a flavivirus related to yellow fever, dengue, West Nile, and Japanese encephalitis viruses. In 2007 ZIKV caused an outbreak of relatively mild disease characterized by rash, arthralgia, and conjunctivitis on Yap Island in the southwestern Pacific Ocean. This was the first time that ZIKV was detected outside of Africa and Asia. The history, transmission dynamics, virology, and clinical manifestations of ZIKV disease are discussed, along with the possibility for diagnostic confusion between ZIKV illness and dengue.The emergence of ZIKV outside of its previously known geographic range should prompt awareness of the potential for ZIKV to spread to other Pacific islands and the Americas. PMID:19788800

  20. Schmallenberg virus infection.

    PubMed

    Wernike, K; Elbers, A; Beer, M

    2015-08-01

    Since Schmallenberg virus, an orthobunyavirus of the Simbu serogroup, was identified near the German-Dutch border for the first time in late 2011 it has spread extremely quickly and caused a large epidemic in European livestock. The virus, which is transmitted by Culicoides biting midges, infects domestic and wild ruminants. Adult animals show only mild clinical symptoms or none at all, whereas an infection during a critical period of gestation can lead to abortion, stillbirth or the birth of severely malformed offspring. The impact of the disease is usually greater in sheep than in cattle. Vaccination could be an important aspect of disease control. PMID:26601441

  1. Human Immunodeficiency Virus Prevention.

    PubMed

    Davis, Teaniese Latham; DiClemente, Ralph

    2016-04-01

    Human immunodeficiency virus (HIV) is the virus that causes AIDS. Surveillance data from 2012 indicate an estimated 1.2 million people aged 13 years and older were living with HIV infection in the United States, and 12.8% do not know their status. There are approximately 50,000 new HIV infections annually. With no available cure for HIV, primary prevention to reduce incident cases of HIV is essential. Strategies to prevent HIV transmission include reducing sexual risk behavior and needle sharing. The Centers for Disease Control and Prevention has multiple resources available for primary and secondary prevention to reduce disease transmission and severity. PMID:26980130

  2. [ZIKA--VIRUS INFECTION].

    PubMed

    Velev, V

    2016-01-01

    This review summarizes the knowledge of the scientific community for Zika-virus infection. It became popular because of severe congenital damage causes of CNS in newborns whose mothers are infected during pregnancy, as well as the risk of pandemic distribution. Discusses the peculiarities of the biology and ecology of vectors--blood-sucking mosquitoes Aedes; stages in the spread of infection and practical problems which caused during pregnancy. Attention is paid to the recommendations that allow leading national and international medical organizations to deal with the threat Zika-virus infection. PMID:27509655

  3. Barley yellow dwarf viruses.

    PubMed

    Miller, W A; Rasochová, L

    1997-01-01

    Barley yellow dwarf viruses represent one of the most economically important and ubiquitous groups of plant viruses. This review focuses primarily on four research areas in which progress has been most rapid. These include (a) evidence supporting reclassification of BYDVs into two genera; (b) elucidation of gene function and novel mechanisms controlling gene expression; (c) initial forays into understanding the complex interactions between BYDV virions and their aphid vectors; and (d) replication of a BYDV satellite RNA. Economic losses, symptomatology, and means of control of BYD are also discussed. PMID:15012520

  4. Zika virus: Indian perspectives

    PubMed Central

    Mourya, Devendra T.; Shil, Pratip; Sapkal, Gajanan N.; Yadav, Pragya D.

    2016-01-01

    The emergence of Zika virus (ZiV), a mosquito borne Flavivirus like dengue (DEN) and chikungunya (CHIK), in Brazil in 2014 and its spread to various countries have led to a global health emergency. Aedes aegypti is the major vector for ZiV. Fast dissemination of this virus in different geographical areas posses a major threat especially to regions where the population lacks herd immunity against the ZiV and there is abundance of Aedes mosquitoes. In this review, we focus on current global scenario, epidemiology, biology, diagnostic challenges and remedial measures for ZiVconsidering the Indian perspective. PMID:27487998

  5. Zika virus: Indian perspectives.

    PubMed

    Mourya, Devendra T; Shil, Pratip; Sapkal, Gajanan N; Yadav, Pragya D

    2016-05-01

    The emergence of Zika virus (ZiV), a mosquito borne Flavivirus like dengue (DEN) and chikungunya (CHIK), in Brazil in 2014 and its spread to various countries have led to a global health emergency. Aedes aegypti is the major vector for ZiV. Fast dissemination of this virus in different geographical areas posses a major threat especially to regions where the population lacks herd immunity against the ZiV and there is abundance of Aedes mosquitoes. In this review, we focus on current global scenario, epidemiology, biology, diagnostic challenges and remedial measures for ZiVconsidering the Indian perspective. PMID:27487998

  6. Viruses and viral proteins

    PubMed Central

    Verdaguer, Nuria; Ferrero, Diego; Murthy, Mathur R. N.

    2014-01-01

    For more than 30 years X-ray crystallography has been by far the most powerful approach for determining the structures of viruses and viral proteins at atomic resolution. The information provided by these structures, which covers many important aspects of the viral life cycle such as cell-receptor recognition, viral entry, nucleic acid transfer and genome replication, has extensively enriched our vision of the virus world. Many of the structures available correspond to potential targets for antiviral drugs against important human pathogens. This article provides an overview of the current knowledge of different structural aspects of the above-mentioned processes. PMID:25485129

  7. Mapping quantitative trait loci conferring resistance to Tomato spotted wilt virus and leaf spots in a recombinant inbred line population derived from SunOleic 97R and NC94022 in peanut (Arachis hypogaea L.)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Peanut is vulnerable to a range of diseases, such as Tomato spotted wilt virus (TSWV) and leaf spots. The most sustainable and economical solution for managing peanut diseases is development of resistance cultivars. The new breeding line NC94022, high resistance to TSWV and moderate resistance to le...

  8. Restorative Justice Scripts in Ursula K. Le Guin's "Voices"

    ERIC Educational Resources Information Center

    Oziewicz, Marek C.

    2011-01-01

    This essay examines restorative justice scripting in "Voices", the second volume of Ursula K. Le Guin's "Annals of the Western Shore." Narrated by a rape-child, "Voices" is the story of an occupied city-state and of how the conquered and the conquerors negotiate a formula for peaceful coexistence. They are able to do so by enacting a restorative…

  9. Decolonizing the Choctaws: Teaching LeAnne Howe's "Shell Shaker"

    ERIC Educational Resources Information Center

    Hollrah, Patrice

    2004-01-01

    "Shell Shaker" (2001) by LeAnne Howe (Choctaw) is a novel that gives students an opportunity to learn that the history and culture of the Choctaw Nation of Oklahoma are alive today. Winner of the Before Columbus Foundation American Book Award in 2002, the novel deals with two parallel stories that converge in the present, one about the eighteenth…

  10. Le Dernier Cartoucherie: Refuge and the Performance of Care

    ERIC Educational Resources Information Center

    Fisek, Emine

    2008-01-01

    In 2003, the Paris-based theatre company Theatre du Soleil launched "Le Dernier Caravanserail: Odyssees", a collaborative creation based on stories that company members had collected from refugees at the Sangatte refugee camp outside Calais, among other locations. Scenes of moral reasoning dotted the six-hour spectacle, calling to mind the…

  11. LeRC in-house experimental research

    NASA Technical Reports Server (NTRS)

    Lyons, Valerie J.

    1992-01-01

    The topics covered include the following: LeRC in-house experimental research; combustion concepts; schedule for in-house experiments; lean premixed prevaporized combustion; comparisons of low NO(x) lean premixed/prevaporized data; rich burn/quick quench/lean burn (RQL); RQL combustion; fuel rich catalytic combustion; advanced diagnostics; and ceramic matrix liner test rig.

  12. Ursula LeGuin's Magical World of Earthsea.

    ERIC Educational Resources Information Center

    Griffin, Jan M.

    1996-01-01

    Discusses how Ursula LeGuin's Earthsea Trilogy reflects her belief in Taoist philosophy as well as her skill in telling stories of magic and adventure. Notes that the three books can be described as coming-of-age novels in which three separate individuals struggle to become mature, responsible, whole adults. (RS)

  13. MoLeNET Mobile Learning Conference 2009: Research Papers

    ERIC Educational Resources Information Center

    Guy Parker, Ed.

    2010-01-01

    The Mobile Learning Network (MoLeNET) is a unique collaborative approach to encouraging, supporting, expanding and promoting mobile learning, primarily in English post-14 education and training, via supported shared cost mobile learning projects. Collaboration at national level involves participating institutions and the Learning and Skills…

  14. LHC, le Big Bang en éprouvette

    ScienceCinema

    None

    2011-10-06

    Notre compréhension de l?Univers est en train de changer? Bar des Sciences - Tout public Débat modéré par Marie-Odile Montchicourt, journaliste de France Info. Evenement en vidéoconférence entre le Globe de la science et de l?innovation, le bar le Baloard de Montpellier et la Maison des Métallos à Paris. Intervenants au CERN : Philippe Charpentier et Daniel Froideveaux, physiciens au CERN. Intervenants à Paris : Vincent Bontemps, philosophe et chercheur au CEA ; Jacques Arnould, philosophe, historien des sciences et théologien, Jean-Jacques Beineix, réalisateur, producteur, scénariste de cinéma. Intervenants à Montpellier (LPTA) : André Neveu, physicien théoricien et directeur de recherche au CNRS ; Gilbert Moultaka, physicien théoricien et chargé de recherche au CNRS. Partenariat : CERN, CEA, IN2P3, Université MPL2 (LPTA) Dans le cadre de la Fête de la science 2008

  15. Junín Virus Pathogenesis and Virus Replication

    PubMed Central

    Grant, Ashley; Seregin, Alexey; Huang, Cheng; Kolokoltsova, Olga; Brasier, Allan; Peters, Clarence; Paessler, Slobodan

    2012-01-01

    Junín virus, the etiological agent of Argentine hemorrhagic fever, causes significant morbidity and mortality. The virus is spread through the aerosolization of host rodent excreta and endemic to the humid pampas of Argentina. Recently, significant progress has been achieved with the development of new technologies (e.g. reverse genetics) that have expanded knowledge about the pathogenesis and viral replication of Junín virus. We will review the pathogenesis of Junín virus in various animal models and the role of innate and adaptive immunity during infection. We will highlight current research regarding the role of molecular biology of Junín virus in elucidating virus attenuation. We will also summarize current knowledge on Junín virus pathogenesis focusing on the recent development of vaccines and potential therapeutics. PMID:23202466

  16. Le syndrome d'embolie graisseuse post traumatique

    PubMed Central

    Berdai, Adnane Mohamed; Shimi, Abdelkarim; Khatouf, Mohammed

    2014-01-01

    Le syndrome d'embolie graisseuse est une complication grave des fractures des os longs, il est la conséquence de la dissémination des particules graisseuses dans la microcirculation. L'objectif de ce travail est de déterminer le profil épidémiologique, la présentation clinique et paraclinique de ce syndrome et sa prise en charge thérapeutique. Notre étude porte sur 11 cas de syndrome d'embolie graisseuse colligés au service de réanimation A1 au centre hospitalier universitaire Hassan II de Fès, de Janvier 2009 à Juin 2012. Le diagnostic positif est basé sur les critères de Gurd. Les cas collectés se caractérisent par la prédominance du sexe masculin, d'un âge inférieur à 40 ans, présentant une fracture fémorale. Ce syndrome survient souvent dans les 72 heures après le traumatisme. La présentation clinique est dominée par l'hypoxémie et les troubles de conscience. Sur le plan biologique: l'anémie et la thrombopénie sont les manifestations les plus fréquentes. La prise en charge est symptomatique, 63% des patients ont nécessité l'intubation et la ventilation. L’évolution n'est pas toujours bénigne. Nos résultats confirme le polymorphisme de la présentation clinique et paraclinique du syndrome d'embolie graisseuse. Le diagnostic de ce syndrome se base sur des critères cliniques, mais reste essentiellement un diagnostic d’élimination. La prise en charge est symptomatique. La prévention de ce syndrome est essentielle et se base sur une fixation précoce des fractures des os longs. PMID:25452829

  17. Connecting Instructional and Cognitive Aspects of an LE: A Study of the Global Seminar Project

    ERIC Educational Resources Information Center

    Savelyeva, Tamara

    2012-01-01

    My research problem is based on the lack of unifying conceptual cohesion between the discourses concerning cognitive and instructional aspects of learning environments (LE). I contrast that lack with practical developments of LE studies connected at the level of practical implementation and evaluation. Next, I briefly review the LE boundaries,…

  18. Les aspects des frottis cervico-vaginaux chez les femmes vivants avec le VIH suivies à Thiès/Sénégal et association avec le degré d'immunodépression

    PubMed Central

    Bammo, Mariama; Dioussé, Pauline; Thiam, Marietou; Diop, Madoky Maguatte; Berthe, Adama; Faye, Flugence Abdou; Diallo, Thierno Abdoul Aziz; Sarr, Fatou Seck; Dione, Haby; Toure, Papa Souleymane; Diop, Bernard Marcel; Ka, Mamadou Mortalla

    2015-01-01

    De nombreuses études ont démontré que les femmes infectées par le VIH ont un risque accru de survenue de néoplasies cervicales intra épithéliales. L'association entre les deux affections étant bidirectionnelle, l'objectif était de décrire les anomalies cervicales chez les femmes séropositives au virus de l'immunodéficience humaine (VIH), de rechercher des facteurs associés et de proposer des recommandations en termes de suivi de ces femmes. Il s'agissait d'une étude transversale, multicentrique recensant l'ensemble des frottis cervico-vaginaux (FCV) et des colposcopies des patientes infectées par le VIH entre 2012 et 2014 dans les services de dermatologie de Thiès et de Mbour. Les données étaient recueillies et analysées par le logiciel EPI Info 2012 version 3.5.4. Les tests statistiques ont été effectués avec un seuil de significativité p <0,05. Etaient inclus 125 patientes. L’âge moyen était de 38,98 ± 10.2 ans [20-77]. Il n'y avait aucun signe d'appels dans 82.4%. Le FCV était normal dans 32.8%, inflammatoire dans 44.8%. Les anomalies cytologiques concernaient 22,4% dont, ASC-H (suspicion de lésions de haut grade: 2.4%), LSIL (lésions de bas grade: 8.8%), HSIL (lésions de haut grade: 4%). Leur majorité (60.7%) avaient un taux de CD4 < 500 et étaient au stade 3 de l'OMS dans 64.3%; la biopsie montrait une dysplasie sévère chez 37.5% des patientes ayant pu réaliser cet examen. Deux patientes ont bénéficié d'un traitement curatif notamment l'exérèse chirurgicale. La survenue de dysplasies cervicales même précoces semble être associée à un stade avancé de l'infection VIH. Un dépistage et un traitement précoces sont absolument nécessaires. PMID:26834915

  19. Le traitement familial des enfants et des adolescents anorexiques : Des lignes directrices pour le médecin communautaire

    PubMed Central

    Findlay, S; Pinzon, J; Taddeo, D; Katzman, DK

    2010-01-01

    L’anorexie mentale (AM) est une maladie grave qui met la vie en danger et qui fait généralement son apparition pendant l’adolescence. Les données probantes au sujet du traitement optimal de l’AM chez les enfants et les adolescents sont en croissance, mais il reste beaucoup à apprendre. Même si les démarches thérapeutiques actuelles varient au Canada et ailleurs, les données jusqu’à présent indiquent que le traitement familial (TF) est le plus efficace pour les enfants et les adolescents anorexiques. Un élément essentiel du modèle de TF, c’est que les parents sont investis de la responsabilité de rétablir la santé physique de leur enfant et de s’assurer de la reprise complète de son poids. Le médecin qui comprend les principes fondamentaux et la philosophie du TF peut mettre en place les éléments de cette intervention fondée sur des faits probants auprès des jeunes patients anorexiques et de leur famille.

  20. Séroprévalence du virus de l'herpès humain-8 chez des patients VIH positif à l'hôpital général de Yaoundé – Cameroun

    PubMed Central

    Jacky, Njiki Bikoï; Paul, Ndom; Lilian, Mupang; Sylvie, Agokeng Demanou

    2015-01-01

    L'épidémiologie de l'infection par le virus herpès humain de type 8 (HHV8) associée à celle à VIH, reste encore méconnue au Cameroun, bien que le pays soit considéré comme une zone endémique pour ces deux virus. L'objectif de ce travail était de ressortir le profil de la séroprévalence du HHV8 au sein de notre population d'étude. 57 personnes ont été recrutées à l'Hôpital Général de Yaoundé et suivies sur une durée 12 mois. Des anticorps IgG anti-HHV8 ont été déterminés par ELISA. Des paramètres autres, tels que l'âge, le sexe, le stade des maladies (SK et VIH/SIDA), le protocole ARV, ainsi que les taux de CD4 ont été utilisés pour déterminer les variables associées à la séropositivité au HHV8. Cette association a été évaluée par le test khi carré. La séroprévalence du HHV8 était de 90% dans notre population en début d'étude et de 74% douze mois plus tard, une séroprévalence qui restait élevée quelque soit le profil clinique, la tranche d'âge, le sexe ou le taux de CD4+ de l'individu. Aucune variable de l'étude n'était significativement associée à la séropositivité du HHV8. Le virus HHV8 semblait circuler au sein de notre population d'étude. Cependant l'on constate, douze mois plus tard, l'absence de manifestations cliniques du SK chez les patients VIH+ positifs, malgré des titres très élevés en IgG anti-HHV8. PMID:26090027

  1. Bat flight and zoonotic viruses

    USGS Publications Warehouse

    O'Shea, Thomas; Cryan, Paul M.; Cunningham, Andrew A.; Fooks, Anthony R.; Hayman, David T.S.; Luis, Angela D.; Peel, Alison J.; Plowright, Raina K.; Wood, James L.N.

    2014-01-01

    Bats are sources of high viral diversity and high-profile zoonotic viruses worldwide. Although apparently not pathogenic in their reservoir hosts, some viruses from bats severely affect other mammals, including humans. Examples include severe acute respiratory syndrome coronaviruses, Ebola and Marburg viruses, and Nipah and Hendra viruses. Factors underlying high viral diversity in bats are the subject of speculation. We hypothesize that flight, a factor common to all bats but to no other mammals, provides an intensive selective force for coexistence with viral parasites through a daily cycle that elevates metabolism and body temperature analogous to the febrile response in other mammals. On an evolutionary scale, this host–virus interaction might have resulted in the large diversity of zoonotic viruses in bats, possibly through bat viruses adapting to be more tolerant of the fever response and less virulent to their natural hosts.

  2. Bat Flight and Zoonotic Viruses

    PubMed Central

    Cryan, Paul M.; Cunningham, Andrew A.; Fooks, Anthony R.; Hayman, David T.S.; Luis, Angela D.; Peel, Alison J.; Plowright, Raina K.; Wood, James L.N.

    2014-01-01

    Bats are sources of high viral diversity and high-profile zoonotic viruses worldwide. Although apparently not pathogenic in their reservoir hosts, some viruses from bats severely affect other mammals, including humans. Examples include severe acute respiratory syndrome coronaviruses, Ebola and Marburg viruses, and Nipah and Hendra viruses. Factors underlying high viral diversity in bats are the subject of speculation. We hypothesize that flight, a factor common to all bats but to no other mammals, provides an intensive selective force for coexistence with viral parasites through a daily cycle that elevates metabolism and body temperature analogous to the febrile response in other mammals. On an evolutionary scale, this host–virus interaction might have resulted in the large diversity of zoonotic viruses in bats, possibly through bat viruses adapting to be more tolerant of the fever response and less virulent to their natural hosts. PMID:24750692

  3. Satellite RNAs and Satellite Viruses.

    PubMed

    Palukaitis, Peter

    2016-03-01

    Satellite RNAs and satellite viruses are extraviral components that can affect either the pathogenicity, the accumulation, or both of their associated viruses while themselves being dependent on the associated viruses as helper viruses for their infection. Most of these satellite RNAs are noncoding RNAs, and in many cases, have been shown to alter the interaction of their helper viruses with their hosts. In only a few cases have the functions of these satellite RNAs in such interactions been studied in detail. In particular, work on the satellite RNAs of Cucumber mosaic virus and Turnip crinkle virus have provided novel insights into RNAs functioning as noncoding RNAs. These effects are described and potential roles for satellite RNAs in the processes involved in symptom intensification or attenuation are discussed. In most cases, models describing these roles involve some aspect of RNA silencing or its suppression, either directly or indirectly involving the particular satellite RNA. PMID:26551994

  4. Bat flight and zoonotic viruses.

    PubMed

    O'Shea, Thomas J; Cryan, Paul M; Cunningham, Andrew A; Fooks, Anthony R; Hayman, David T S; Luis, Angela D; Peel, Alison J; Plowright, Raina K; Wood, James L N

    2014-05-01

    Bats are sources of high viral diversity and high-profile zoonotic viruses worldwide. Although apparently not pathogenic in their reservoir hosts, some viruses from bats severely affect other mammals, including humans. Examples include severe acute respiratory syndrome coronaviruses, Ebola and Marburg viruses, and Nipah and Hendra viruses. Factors underlying high viral diversity in bats are the subject of speculation. We hypothesize that flight, a factor common to all bats but to no other mammals, provides an intensive selective force for coexistence with viral parasites through a daily cycle that elevates metabolism and body temperature analogous to the febrile response in other mammals. On an evolutionary scale, this host-virus interaction might have resulted in the large diversity of zoonotic viruses in bats, possibly through bat viruses adapting to be more tolerant of the fever response and less virulent to their natural hosts. PMID:24750692

  5. From Shakespeare to Viruses

    ScienceCinema

    Sung-Hou Kim

    2010-01-08

    Berkeley Lab scientists have created a unique new tool for analyzing and comparing long sets of data, be it the genomes of mammals or viruses, or the works of Shakespeare. The results of the Shakespeare analysis surprised scholars with their accuracy

  6. Raspberry leaf curl virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Raspberry leaf curl virus (RLCV) is limited to hosts in the genus Rubus and is transmitted persistently by the small raspberry aphid, Aphis rubicola Oestlund. It is found only in North America, principally in the northeastern United States and southeastern Canada and in the Rocky Mountain regions of...

  7. From Shakespeare to Viruses

    ScienceCinema

    Kim, Sung-Hou

    2013-05-29

    Berkeley Lab scientists have created a unique new tool for analyzing and comparing long sets of data, be it the genomes of mammals or viruses, or the works of Shakespeare. The results of the Shakespeare analysis surprised scholars with their accuracy.

  8. Turnip Yellow Mosaic Virus

    NASA Technical Reports Server (NTRS)

    2000-01-01

    The bumpy exterior of the turnip yellow mosaic virus (TYMV) protein coat, or capsid, was defined in detail by Dr. Alexander McPherson of the University of California, Irvin using proteins crystallized in space for analysis on Earth. TYMV is an icosahedral virus constructed from 180 copies of the same protein arranged into 12 clusters of five proteins (pentamers), and 20 clusters of six proteins (hexamers). The final TYMV structure led to the unexpected hypothesis that the virus releases its RNA by essentially chemical-mechanical means. Most viruses have fairly flat coats, but in TYNV, the fold in each protein, called the jellyroll, is clustered at the points where the protein pentamers and hexamers join. The jellyrolls are almost standing on end, producing a bumpy surface with knobs at all of the pentamers and hexamers. At the inside surface of the pentamers is a void that is not present at the hexamers. The coating had been seen in early stuties of TYMV, but McPherson's atomic structure shows much more detail. The inside surface is strikingly, and unexpectedly, different than the outside. While the pentamers contain a central void on the inside, the hexameric units contain peptides linked to each other, forming a ring or, more accurately, rings to fill the void. Credit: Dr. Alexander McPherson, University of California, Irvine

  9. Viruses of Haloarchaea

    PubMed Central

    Luk, Alison W. S.; Williams, Timothy J.; Erdmann, Susanne; Papke, R. Thane; Cavicchioli, Ricardo

    2014-01-01

    In hypersaline environments, haloarchaea (halophilic members of the Archaea) are the dominant organisms, and the viruses that infect them, haloarchaeoviruses are at least ten times more abundant. Since their discovery in 1974, described haloarchaeoviruses include head-tailed, pleomorphic, spherical and spindle-shaped morphologies, representing Myoviridae, Siphoviridae, Podoviridae, Pleolipoviridae, Sphaerolipoviridae and Fuselloviridae families. This review overviews current knowledge of haloarchaeoviruses, providing information about classification, morphotypes, macromolecules, life cycles, genetic manipulation and gene regulation, and host-virus responses. In so doing, the review incorporates knowledge from laboratory studies of isolated viruses, field-based studies of environmental samples, and both genomic and metagenomic analyses of haloarchaeoviruses. What emerges is that some haloarchaeoviruses possess unique morphological and life cycle properties, while others share features with other viruses (e.g., bacteriophages). Their interactions with hosts influence community structure and evolution of populations that exist in hypersaline environments as diverse as seawater evaporation ponds, to hot desert or Antarctic lakes. The discoveries of their wide-ranging and important roles in the ecology and evolution of hypersaline communities serves as a strong motivator for future investigations of both laboratory-model and environmental systems. PMID:25402735

  10. Cold Facts about Viruses.

    ERIC Educational Resources Information Center

    Pea, Celeste; Sterling, Donna R.

    2002-01-01

    Provides ways for students to demonstrate their understanding of scientific concepts and skills. Describes a mini-unit around the cold in which students can relate humans to viruses. Includes activities and a modified simulation that provides questions to guide students. Discusses ways that allows students to apply prior knowledge, take ownership…

  11. From Shakespeare to Viruses

    SciTech Connect

    Sung-Hou Kim

    2009-02-09

    Berkeley Lab scientists have created a unique new tool for analyzing and comparing long sets of data, be it the genomes of mammals or viruses, or the works of Shakespeare. The results of the Shakespeare analysis surprised scholars with their accuracy

  12. From Shakespeare to Viruses

    SciTech Connect

    Kim, Sung-Hou

    2009-01-01

    Berkeley Lab scientists have created a unique new tool for analyzing and comparing long sets of data, be it the genomes of mammals or viruses, or the works of Shakespeare. The results of the Shakespeare analysis surprised scholars with their accuracy.

  13. VIRUSES IN GROUNDWATER

    EPA Science Inventory

    The microbial contamination of ground water is a serious problem that can result in large outbreaks of waterborne disease. The purpose of this article is to review the literature available on viruses in ground water in order to evaluate the present state-of-knowledge, assess the ...

  14. Newcastle disease virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Newcastle disease virus (NDV), a member of the Avulavirus genus in the Paramyxoviridae family, has a ribonucleic acid (RNA) genome that is negative sense, non-segmented, and single-stranded. The genome codes for six structural proteins: nucleocapsid, phosphoprotein, matrix, fusion, hemagglutinin-neu...

  15. Varicella zoster virus latency

    PubMed Central

    Eshleman, Emily; Shahzad, Aamir; Cohrs, Randall J

    2011-01-01

    Primary infection by varicella zoster virus (VZV) typically results in childhood chickenpox, at which time latency is established in the neurons of the cranial nerve, dorsal root and autonomic ganglia along the entire neuraxis. During latency, the histone-associated virus genome assumes a circular episomal configuration from which transcription is epigenetically regulated. The lack of an animal model in which VZV latency and reactivation can be studied, along with the difficulty in obtaining high-titer cell-free virus, has limited much of our understanding of VZV latency to descriptive studies of ganglia removed at autopsy and analogy to HSV-1, the prototype alphaherpesvirus. However, the lack of miRNA, detectable latency-associated transcript and T-cell surveillance during VZV latency highlight basic differences between the two neurotropic herpesviruses. This article focuses on VZV latency: establishment, maintenance and reactivation. Comparisons are made with HSV-1, with specific attention to differences that make these viruses unique human pathogens. PMID:21695042

  16. The FEFM Virus.

    ERIC Educational Resources Information Center

    Cjelli, Dirk

    1994-01-01

    Discussion of human performance technology (HPT) interventions focuses on requests for solutions to problems that involve conflict between the FEFM ("Fix 'em for me") Virus and the WIIFM ("What's in it for me?") Requirement. Building a relationship of mutual trust and confidence with the client and demonstrating responsiveness are advocated. (LRW)

  17. Cell injury with viruses.

    PubMed Central

    Tamm, I.

    1975-01-01

    The inhibitions of cellular protein and RNA synthesis in picornavirus-infected cells are early events which require only limited synthesis of virus-specific proteins. The inhibition of cellular protein synthesis appears to be due to blocking of the association of ribosomes with host messenger RNA. Inhibition of cellular RNA synthesis involves inactivation of the template-enzyme complex and affects ribosomal RNA synthesis before messenger RNA synthesis. Inhibition of cellular DNA synthesis also occurs early and may be secondary to inhibition of cellular protein synthesis. Early chromatid breaks may be related to inhibitions of cellular protein and nucleic acid synthesis. Stimulation of phospholipid synthesis in picornavirus-infected cells also requires only limited synthesis of virus-specific proteins. In contrast, release of lysosomal enzymes, proliferation of smooth cytoplasmic membranes, cellular vacuolization, retraction, and rounding, and diffuse chromosomal changes related to karyorrhexis and pyknosis are all dependent on considerable synthesis of virus-specific proteins during the middle part of the picornavirus growth cycle. The early virus-induced alterations in cellular biosynthetic processes are not the direct or sole cause of the subsequent marked pathologic changes in the membranes and chromosomes of the cell. Images Figure 1 PMID:1180330

  18. Yellow Fever Virus Infection

    PubMed Central

    David-West, Tam. S.; Smith, J. A.

    1971-01-01

    A sequential and quantitative survey of brain and liver of suckling mice for infective virus and complement-fixing antigen, after infection with yellow fever virus, showed that while there was progressive increase of infective virus content in both organs, only the brain showed a corresponding rise in CF antigen. Histopathological examination revealed that the liver was not significantly involved. The target organ was the brain, where the progressive pathological changes culminated in an acute encephalitis by the 3rd day of experiment. Organ destruction began with the molecular layer of the grey matter. But by the 4th day after infection the entire cerebral cortex was involved. At the initial stages the hippocampus was particularly affected. Tissue damage did not appear to be entirely due to the differential quantitative localization of infective virus. It was hypothesized that the CF antigen acting singly or in conjunction with some hypothetical proteins may be principally involved in the pathological outcome of the disease. ImagesFigs. 7-9Figs. 3-6 PMID:5582071

  19. Virus Chapter: Dicistrovidae

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Dicistroviridae family comprises viruses infecting both beneficial arthropods such as honey bees and shrimp and insect pests of medical and agricultural importance. During the last five years, advances in sequencing and phylogenetic analysis have led to the discovery and identification of sever...

  20. Viruses of haloarchaea.

    PubMed

    Luk, Alison W S; Williams, Timothy J; Erdmann, Susanne; Papke, R Thane; Cavicchioli, Ricardo

    2014-01-01

    In hypersaline environments, haloarchaea (halophilic members of the Archaea) are the dominant organisms, and the viruses that infect them, haloarchaeoviruses are at least ten times more abundant. Since their discovery in 1974, described haloarchaeoviruses include head-tailed, pleomorphic, spherical and spindle-shaped morphologies, representing Myoviridae, Siphoviridae, Podoviridae, Pleolipoviridae, Sphaerolipoviridae and Fuselloviridae families. This review overviews current knowledge of haloarchaeoviruses, providing information about classification, morphotypes, macromolecules, life cycles, genetic manipulation and gene regulation, and host-virus responses. In so doing, the review incorporates knowledge from laboratory studies of isolated viruses, field-based studies of environmental samples, and both genomic and metagenomic analyses of haloarchaeoviruses. What emerges is that some haloarchaeoviruses possess unique morphological and life cycle properties, while others share features with other viruses (e.g., bacteriophages). Their interactions with hosts influence community structure and evolution of populations that exist in hypersaline environments as diverse as seawater evaporation ponds, to hot desert or Antarctic lakes. The discoveries of their wide-ranging and important roles in the ecology and evolution of hypersaline communities serves as a strong motivator for future investigations of both laboratory-model and environmental systems. PMID:25402735

  1. Varicella zoster virus infection.

    PubMed

    Gershon, Anne A; Breuer, Judith; Cohen, Jeffrey I; Cohrs, Randall J; Gershon, Michael D; Gilden, Don; Grose, Charles; Hambleton, Sophie; Kennedy, Peter G E; Oxman, Michael N; Seward, Jane F; Yamanishi, Koichi

    2015-01-01

    Infection with varicella zoster virus (VZV) causes varicella (chickenpox), which can be severe in immunocompromised individuals, infants and adults. Primary infection is followed by latency in ganglionic neurons. During this period, no virus particles are produced and no obvious neuronal damage occurs. Reactivation of the virus leads to virus replication, which causes zoster (shingles) in tissues innervated by the involved neurons, inflammation and cell death - a process that can lead to persistent radicular pain (postherpetic neuralgia). The pathogenesis of postherpetic neuralgia is unknown and it is difficult to treat. Furthermore, other zoster complications can develop, including myelitis, cranial nerve palsies, meningitis, stroke (vasculopathy), retinitis, and gastroenterological infections such as ulcers, pancreatitis and hepatitis. VZV is the only human herpesvirus for which highly effective vaccines are available. After varicella or vaccination, both wild-type and vaccine-type VZV establish latency, and long-term immunity to varicella develops. However, immunity does not protect against reactivation. Thus, two vaccines are used: one to prevent varicella and one to prevent zoster. In this Primer we discuss the pathogenesis, diagnosis, treatment, and prevention of VZV infections, with an emphasis on the molecular events that regulate these diseases. For an illustrated summary of this Primer, visit: http://go.nature.com/14xVI1. PMID:27188665

  2. Honey Bee Viruses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Viruses are significant threats to the health and well-being of the honey bee, Apis mellifera. To alleviate the threats posed by these invasive organisms, a better understanding of bee viral infections will be of crucial importance in developing effective and environmentally-benign disease control ...

  3. GENOME OF HORSEPOX VIRUS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Here we present the genomic sequence of horsepox virus (HSPV) isolate MNR-76, an orthopoxvirus (OPV) isolated in 1976 from diseased Mongolian horses. The 212 kbp genome contained 7.5 kbp inverted terminal repeats (ITR) and lacked extensive terminal tandem repetition. HSPV contained 236 ORFs with sim...

  4. A vaccinia virus renaissance

    PubMed Central

    Verardi, Paulo H.; Titong, Allison; Hagen, Caitlin J.

    2012-01-01

    In 1796, Edward Jenner introduced the concept of vaccination with cowpox virus, an Orthopoxvirus within the family Poxviridae that elicits cross protective immunity against related orthopoxviruses, including smallpox virus (variola virus). Over time, vaccinia virus (VACV) replaced cowpox virus as the smallpox vaccine, and vaccination efforts eventually led to the successful global eradication of smallpox in 1979. VACV has many characteristics that make it an excellent vaccine and that were crucial for the successful eradication of smallpox, including (1) its exceptional thermal stability (a very important but uncommon characteristic in live vaccines), (2) its ability to elicit strong humoral and cell-mediated immune responses, (3) the fact that it is easy to propagate, and (4) that it is not oncogenic, given that VACV replication occurs exclusively within the host cell cytoplasm and there is no evidence that the viral genome integrates into the host genome. Since the eradication of smallpox, VACV has experienced a renaissance of interest as a viral vector for the development of recombinant vaccines, immunotherapies, and oncolytic therapies, as well as the development of next-generation smallpox vaccines. This revival is mainly due to the successful use and extensive characterization of VACV as a vaccine during the smallpox eradication campaign, along with the ability to genetically manipulate its large dsDNA genome while retaining infectivity and immunogenicity, its wide mammalian host range, and its natural tropism for tumor cells that allows its use as an oncolytic vector. This review provides an overview of new uses of VACV that are currently being explored for the development of vaccines, immunotherapeutics, and oncolytic virotherapies. PMID:22777090

  5. Viruses and neurodegeneration

    PubMed Central

    2013-01-01

    Neurodegenerative diseases (NDs) are chronic degenerative diseases of the central nervous system (CNS), which affect 37 million people worldwide. As the lifespan increases, the NDs are the fourth leading cause of death in the developed countries and becoming increasingly prevalent in developing countries. Despite considerable research, the underlying mechanisms remain poorly understood. Although the large majority of studies do not show support for the involvement of pathogenic aetiology in classical NDs, a number of emerging studies show support for possible association of viruses with classical neurodegenerative diseases in humans. Space does not permit for extensive details to be discussed here on non-viral-induced neurodegenerative diseases in humans, as they are well described in literature. Viruses induce alterations and degenerations of neurons both directly and indirectly. Their ability to attack the host immune system, regions of nervous tissue implies that they can interfere with the same pathways involved in classical NDs in humans. Supporting this, many similarities between classical NDs and virus-mediated neurodegeneration (non-classical) have been shown at the anatomic, sub-cellular, genomic and proteomic levels suggesting that viruses can explain neurodegenerative disorders mechanistically. The main objective of this review is to provide readers a detailed snapshot of similarities viral and non-viral neurodegenerative diseases share, so that mechanistic pathways of neurodegeneration in human NDs can be clearly understood. Viruses can guide us to unveil these pathways in human NDs. This will further stimulate the birth of new concepts in the biological research, which is needed for gaining deeper insights into the treatment of human NDs and delineate mechanisms underlying neurodegeneration. PMID:23724961

  6. Western equine encephalitis virus is a recombinant virus.

    PubMed Central

    Hahn, C S; Lustig, S; Strauss, E G; Strauss, J H

    1988-01-01

    The alphaviruses are a group of 26 mosquito-borne viruses that cause a variety of human diseases. Many of the New World alphaviruses cause encephalitis, whereas the Old World viruses more typically cause fever, rash, and arthralgia. The genome is a single-stranded nonsegmented RNA molecule of + polarity; it is about 11,700 nucleotides in length. Several alphavirus genomes have been sequenced in whole or in part, and these sequences demonstrate that alpha-viruses have descended from a common ancestor by divergent evolution. We have now obtained the sequence of the 3'-terminal 4288 nucleotides of the RNA of the New World Alphavirus western equine encephalitis virus (WEEV). Comparisons of the nucleotide and amino acid sequences of WEEV with those of other alphaviruses clearly show that WEEV is recombinant. The sequences of the capsid protein and of the (untranslated) 3'-terminal 80 nucleotides of WEEV are closely related to the corresponding sequences of the New World Alphavirus eastern equine encephalitis virus (EEEV), whereas the sequences of glycoproteins E2 and E1 of WEEV are more closely related to those of an Old World virus, Sindbis virus. Thus, WEEV appears to have arisen by recombination between an EEEV-like virus and a Sindbis-like virus to give rise to a new virus with the encephalogenic properties of EEEV but the antigenic specificity of Sindbis virus. There has been speculation that recombination might play an important role in the evolution of RNA viruses. The current finding that a widespread and successful RNA virus is recombinant provides support for such an hypothesis. Images PMID:3413072

  7. The scope of the LeChatelier Principle

    NASA Astrophysics Data System (ADS)

    George M., Lady; Quirk, James P.

    2007-07-01

    LeChatelier [Comptes Rendus 99 (1884) 786; Ann. Mines 13 (2) (1888) 157] showed that a physical system's “adjustment” to a disturbance to its equilibrium tended to be smaller as constraints were added to the adjustment process. Samuelson [Foundations of Economic Analysis, Harvard University Press, Cambridge, 1947] applied this result to economics in the context of the comparative statics of the actions of individual agents characterized as the solutions to optimization problems; and later (1960), extended the application of the Principle to a stable, multi-market equilibrium and the case of all commodities gross substitutes [e.g., L. Metzler, Stability of multiple markets: the hicks conditions. Econometrica 13 (1945) 277-292]. Refinements and alternative routes of derivation have appeared in the literature since then, e.g., Silberberg [The LeChatelier Principle as a corollary to a generalized envelope theorem, J. Econ. Theory 3 (1971) 146-155; A revision of comparative statics methodology in economics, or, how to do comparative statics on the back of an envelope, J. Econ. Theory 7 (1974) 159-172], Milgrom and Roberts [The LeChatelier Principle, Am. Econ. Rev. 86 (1996) 173-179], W. Suen, E. Silberberg, P. Tseng [The LeChatelier Principle: the long and the short of it, Econ. Theory 16 (2000) 471-476], and Chavas [A global analysis of constrained behavior: the LeChatelier Principle ‘in the large’, South. Econ. J. 72 (3) (2006) 627-644]. In this paper, we expand the scope of the Principle in various ways keyed to Samuelson's proposed means of testing comparative statics results (optimization, stability, and qualitative analysis). In the optimization framework, we show that the converse LeChatelier Principle also can be found in constrained optimization problems and for not initially “conjugate” sensitivities. We then show how the Principle and its converse can be found through the qualitative analysis of any linear system. In these terms, the Principle and

  8. Virus movement within grafted watermelon plants

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Watermelon production in Florida is impacted by several viruses including whitefly-transmitted Squash vein yellowing virus (SqVYV), Cucurbit yellow stunting disorder virus and Cucurbit leaf crumple virus, and aphid-transmitted Papaya ringspot virus type W (PRSV-W). While germplasm resistant to some...

  9. Single Virus Genomics: A New Tool for Virus Discovery

    PubMed Central

    Allen, Lisa Zeigler; Ishoey, Thomas; Novotny, Mark A.; McLean, Jeffrey S.; Lasken, Roger S.; Williamson, Shannon J.

    2011-01-01

    Whole genome amplification and sequencing of single microbial cells has significantly influenced genomics and microbial ecology by facilitating direct recovery of reference genome data. However, viral genomics continues to suffer due to difficulties related to the isolation and characterization of uncultivated viruses. We report here on a new approach called ‘Single Virus Genomics’, which enabled the isolation and complete genome sequencing of the first single virus particle. A mixed assemblage comprised of two known viruses; E. coli bacteriophages lambda and T4, were sorted using flow cytometric methods and subsequently immobilized in an agarose matrix. Genome amplification was then achieved in situ via multiple displacement amplification (MDA). The complete lambda phage genome was recovered with an average depth of coverage of approximately 437X. The isolation and genome sequencing of uncultivated viruses using Single Virus Genomics approaches will enable researchers to address questions about viral diversity, evolution, adaptation and ecology that were previously unattainable. PMID:21436882

  10. Neuroteratogenic Viruses and Lessons for Zika Virus Models.

    PubMed

    Kim, Kenneth; Shresta, Sujan

    2016-08-01

    The Centers for Disease Control and Prevention has confirmed that Zika virus (ZIKV) causes congenital microcephaly. ZIKV now joins five other neuroteratogenic (NT) viruses in humans and ZIKV research is in its infancy. In addition, there is only one other NT human arbovirus (Venezuelan equine encephalitis virus), which is also poorly understood. But further insight into ZIKV can be found by evaluating arboviruses in domestic animals, of which there are at least seven NT viruses, three of which have been well studied. Here we review two key anatomical structures involved in modeling transplacental NT virus transmission: the placenta and the fetal blood-brain barrier. We then survey major research findings regarding transmission of NT viruses for guidance in establishing a mouse model of Zika disease that is crucial for a better understanding of ZIKV transmission and pathogenesis. PMID:27387029

  11. Ultrafast intramolecular charge transfer with N-(4-cyanophenyl)carbazole. Evidence for a LE precursor and dual LE + ICT fluorescence.

    PubMed

    Galievsky, Victor A; Druzhinin, Sergey I; Demeter, Attila; Mayer, Peter; Kovalenko, Sergey A; Senyushkina, Tamara A; Zachariasse, Klaas A

    2010-12-01

    The photophysics of N-(4-cyanophenyl)carbazole (NP4CN) was investigated by using absorption and fluorescence spectra, picosecond fluorescence decays, and femtosecond transient absorption. In the nonpolar n-hexane as well as in the polar solvent acetonitrile (MeCN), a locally excited (LE) state is detected, as a precursor for the intramolecular charge transfer (ICT) state. A LE → ICT reaction time τ(2) at 22 °C of 0.95 ps in ethyl cyanide (EtCN) and 0.32 ps in MeCN is determined from the decay of the LE excited state absorption (ESA) maximum around 620 nm. In the ESA spectrum of NP4CN in n-hexane at a pump-probe delay time of 100 ps, an important contribution of the LE band remains alongside the ICT band, in contrast to what is observed in EtCN and MeCN. This shows that a LE ⇄ ICT equilibrium is established in this solvent and the ICT reaction time of 0.5 ps is equal to the reciprocal of the sum of the forward and backward ICT rate constants 1/(k(a) + k(d)). In the photostationary S(0) → S(n) absorption spectrum of NP4CN in n-hexane and MeCN, an additional CT absorption band appears, absent in the sum of the spectra of its electron donor (D) and acceptor (A) subgroups carbazole and benzonitrile. This CT band is located at an energy of ∼4000 cm(-1) lower than for N-phenylcarbazole (NPC), due to the larger electron affinity of the benzonitrile moiety of NP4CN than the phenyl subunit of NPC. The fluorescence spectrum of NP4CN in n-hexane at 25 °C mainly consists of a structured LE emission, with a small ICT admixture, indicating that a LE → ICT reaction just starts to occur under these conditions. In di-n-pentyl ether (DPeE) and di-n-butyl ether (DBE), a LE emission is found upon cooling at the high-energy edge of the ICT fluorescence band, caused by the onset of dielectric solvent relaxation. This is not the case in more polar solvents, such as diethyl ether (DEE) and MeCN, in which a structureless ICT emission band fully overlaps the strongly quenched LE

  12. Detection of sweet potato viruses in Yunnan and genetic diversity analysis of the common viruses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Two hundred seventy-nine samples with virus-like symptoms collected from 16 regions in Yunnan Province were tested by RT-PCR/PCR using virus-specific primers for 8 sweet potato viruses. Six viruses, Sweet potato chlorotic fleck virus (SPCFV), Sweet Potato feathery mottle virus (SPFMV), Sweet potato ...

  13. LeCroy MQT300A - charge to time converter

    SciTech Connect

    Yamrone, B.; Roberts, K.; Kelly, J.

    1997-12-31

    The MQT300A was developed to offer high resolution (12 bit) and wide dynamic range (18 bit) with reasonable cost, high density and fast conversion time (< 10 {mu}s). The reduced conversion time has allowed its first users the option to choose whether or not to develop a fast clear strategy as part of their trigger system. It can also be used for chamber-mounted applications allowing compact digital data cabling to the remote TDC. The MQT300A is a custom development produced in collaboration with the BELLE collaboration at KEK and the CLEO group at Cornell. In this collaboration Cornell and KEK were partners with LeCroy in both the specification and evaluation of the first prototypes. LeCroy has been responsible for the remainder of the project. The MQT300A is available in LeCroy modules and also as a separate monolithic. The MQT300A was designed to take advantage of the latest generation of multi-hit TDCs, for example the LeCroy 1877S FASTBUS ADC. The 1877S was specifically optimized to improve conversion time and to intelligently minimize the data record size for the MQT300A application. A prototype part was designed and fabricated using a custom bipolar process. Though fully functional it did not meet several important performance specifications. A reiteration with significant redesign of two sections resulted in a part that meets all specifications. The unique encoding algorithm used to provide auto-ranging has had a U.S. patent allowed. The part is now commercially available in production volumes.

  14. Mechanisms of Virus Assembly

    PubMed Central

    Perlmutter, Jason D.; Hagan, Michael F.

    2015-01-01

    Viruses are nanoscale entities containing a nucleic acid genome encased in a protein shell called a capsid, and in some cases surrounded by a lipid bilayer membrane. This review summarizes the physics that govern the processes by which capsids assembles within their host cells and in vitro. We describe the thermodynamics and kinetics for assembly of protein subunits into icosahedral capsid shells, and how these are modified in cases where the capsid assembles around a nucleic acid or on a lipid bilayer. We present experimental and theoretical techniques that have been used to characterize capsid assembly, and we highlight aspects of virus assembly which are likely to receive significant attention in the near future. PMID:25532951

  15. [Ebola virus disease: Update].

    PubMed

    de la Calle-Prieto, Fernando; Arsuaga-Vicente, Marta; Mora-Rillo, Marta; Arnalich-Fernandez, Francisco; Arribas, Jose Ramon

    2016-01-01

    The first known Ebola outbreak occurred in 1976. Since then, 24 limited outbreaks had been reported in Central Africa, but never affecting more than 425 persons. The current outbreak in Western Africa is the largest in history with 28,220 reported cases and 11,291 deaths. The magnitude of the epidemic has caused worldwide alarm. For the first time, evacuated patients were treated outside Africa, and secondary cases have occurred in Spain and the United States. Since the start of the current epidemic, our knowledge about the epidemiology, clinical picture, laboratory findings, and virology of Ebola virus disease has considerably expanded. For the first time, experimental treatment has been tried, and there have been spectacular advances in vaccine development. A review is presented of these advances in the knowledge of Ebola virus disease. PMID:26774254

  16. Phage Displayed Peptides to Avian H5N1 Virus Distinguished the Virus from Other Viruses

    PubMed Central

    Qin, Chengfeng; Ren, Xiaofeng

    2011-01-01

    The purpose of the current study was to identify potential ligands and develop a novel diagnostic test to highly pathogenic avian influenza A virus (HPAI), subtype H5N1 viruses using phage display technology. The H5N1 viruses were used as an immobilized target in a biopanning process using a 12-mer phage display random peptide library. After five rounds of panning, three phages expressing peptides HAWDPIPARDPF, AAWHLIVALAPN or ATSHLHVRLPSK had a specific binding activity to H5N1 viruses were isolated. Putative binding motifs to H5N1 viruses were identified by DNA sequencing. In terms of the minimum quantity of viruses, the phage-based ELISA was better than antiserum-based ELISA and a manual, semi-quantitative endpoint RT-PCR for detecting H5N1 viruses. More importantly, the selected phages bearing the specific peptides to H5N1 viruses were capable of differentiating this virus from other avian viruses in enzyme-linked immunosorbent assays. PMID:21887228

  17. Geographic distribution of Bhanja virus.

    PubMed

    Hubálek, Z

    1987-01-01

    A review on the geographic distribution, vectors and hosts of Bhanja virus (Bunyaviridae) is based on reports about: isolations of the virus; antibody surveys. Bhanja virus has been isolated in 15 countries of Asia, Africa and Europe, and antibodies against it have been detected in 15 additional countries. Vector range includes ticks of the family Ixodidae (subfam. Amblyomminae; not subfam. Ixodinae): 13 species of 6 genera (Haemaphysalis, Dermacentor, Hyalomma, Amblyomma, Rhipicephalus and Boophilus) yielded the virus. Bhanja virus has only rarely been isolated from vertebrates (Atelerix, Xerus, Ovis, Bos; possibly bats), though antibodies have been detected frequently in a wide range of mammals (Ruminantia being the major hosts), in several species of birds (Passeriformes, Galliformes) and even reptiles (Ophisaurus apodus). Natural foci of the Bhanja virus infections are of the boskematic type (sensu Rosický), associated closely with pastures of domestic ruminants infested by ticks in the regions of tropical, subtropical and partly temperate climatic zones. PMID:3108117

  18. Principles of Virus Structural Organization

    PubMed Central

    Prasad, B.V. Venkataram; Schmid, Michael F

    2013-01-01

    Viruses, the molecular nanomachines infecting hosts ranging from prokaryotes to eukaryotes, come in different sizes, shapes and symmetries. Questions such as what principles govern their structural organization, what factors guide their assembly, how these viruses integrate multifarious functions into one unique structure have enamored researchers for years. In the last five decades, following Caspar and Klug's elegant conceptualization of how viruses are constructed, high resolution structural studies using X-ray crystallography and more recently cryo-EM techniques have provided a wealth of information on structures of variety of viruses. These studies have significantly furthered our understanding of the principles that underlie structural organization in viruses. Such an understanding has practical impact in providing a rational basis for the design and development of antiviral strategies. In this chapter, we review principles underlying capsid formation in a variety of viruses, emphasizing the recent developments along with some historical perspective. PMID:22297509

  19. Proteorhodopsin genes in giant viruses

    PubMed Central

    2012-01-01

    Viruses with large genomes encode numerous proteins that do not directly participate in virus biogenesis but rather modify key functional systems of infected cells. We report that a distinct group of giant viruses infecting unicellular eukaryotes that includes Organic Lake Phycodnaviruses and Phaeocystis globosa virus encode predicted proteorhodopsins that have not been previously detected in viruses. Search of metagenomic sequence data shows that putative viral proteorhodopsins are extremely abundant in marine environments. Phylogenetic analysis suggests that giant viruses acquired proteorhodopsins via horizontal gene transfer from proteorhodopsin-encoding protists although the actual donor(s) could not be presently identified. The pattern of conservation of the predicted functionally important amino acid residues suggests that viral proteorhodopsin homologs function as sensory rhodopsins. We hypothesize that viral rhodopsins modulate light-dependent signaling, in particular phototaxis, in infected protists. This article was reviewed by Igor B. Zhulin and Laksminarayan M. Iyer. For the full reviews, see the Reviewers’ reports section. PMID:23036091

  20. Le sumatriptan intranasal pour la migraine chez les enfants

    PubMed Central

    Goldman, Ran D.; Meckler, Garth D.

    2015-01-01

    Résumé Question Je vois de plus en plus d’enfants et d’adolescents qui souffrent de céphalées pouvant se classer dans la catégorie des migraines. J’ai fait des lectures sur le sumatriptan par voie intranasale comme thérapie abortive. Est-ce un traitement efficace? Réponse La migraine aiguë chez les enfants et les adolescents est fréquente et difficile à traiter. Le sumatriptan intranasal est une option sûre et généralement efficace pour les enfants et les adolescents. La dose actuellement recommandée est de 20 mg pour les enfants qui pèsent plus de 40 kg et de 10 mg pour ceux dont le poids se situe entre 20 et 39 kg. Il faudrait faire des études de plus grande envergure pour contrecarrer les limitations des échantillons de petite taille et mieux comprendre la faible concentration plasmique et les effets placebo observés dans les études jusqu’à présent.

  1. Le kyste hydatique du cordon spermatique: une localisation exceptionnelle

    PubMed Central

    Hamdane, Mohamed Moncef; Bougrine, Fethi; Msakni, Issam; Dhaoui-Ghozzi, Amen; Bouziani, Ammar

    2011-01-01

    L’ hydatidose est une anthropo-zoonose due au développement chez l'homme de la forme larvaire du taenia Echinococcus granulosis. La plupart des kystes hydatiques se localisent dans le foie et les poumons. Le kyste hydatique du cordon spermatique est extrêmement rare avec seulement 4 cas rapportés dans la littérature. Les auteurs rapportent dans cet article un nouveau cas d'hydatidose du cordon spermatique. Il s'agissait d'un homme de 40 ans qui consultait pour des douleurs scrotales évoluant depuis huit mois. L'examen clinique a mis en évidence une tuméfaction mobile, inguino-scrotale, droite. L’échographie testiculaire a objectivé une hernie inguinale droite associée à deux kystes épididymaires bilatéraux. Le patient a été opéré pour cure de son hernie avec découverte en per-opératoire d'un kyste du cordon spermatique qui a été réséqué. L'examen anatomopathologique a conclu à une hydatidose du cordon spermatique. PMID:22384304

  2. Airborne pollen and spores of León (Spain)

    NASA Astrophysics Data System (ADS)

    Fernández-González, Delia; Suarez-Cervera, María; Díaz-González, Tomás; Valencia-Barrera, Rosa María

    1993-06-01

    A qualitative and quantitative analysis of airborne pollen and spores was carried out over 2 years (from September 1987 to August 1989) in the city of León. Slides were prepared daily using a volumetric pollen trap, which was placed on the Faculty of Veterinary Science building (University of León) 12m above ground-level. Fifty-one pollen types were observed; the most important of these were: Cupressaceae during the winter, Pinus and Quercus in spring, and Poaceae, Leguminosae and Chenopodiaceae in the summer. The results also showed the existence of a rich mould spore assemblage in the atmosphere. The group of Amerospores ( Penicillium, Aspergillus and Cladosporium) as well as Dictyospores ( Alternaria) were the most abundant; Puccinia was common in the air in August. Fluctuations in the total pollen and spores m3 of air were compared with meteorological parameters (temperature, relative humidity and rainfall). From the daily sampling of the atmosphere of León, considering the maximum and minimum temperature and duration of rainfall, the start of the pollen grain season was observed generally to coincide with a rise in temperature in the absence of rain.

  3. Cytomegalovirus: the stealth virus.

    PubMed

    Robinson, Sharon

    2016-05-01

    Cytomegalovirus (CMV) is an infection, part of the herpes family of viruses which, if contracted during pregnancy, cancause devastating effects on the newborn baby. This article is written by the trustee of a volunteer-based charity, mostly run by mothers of CMV children, who are striving to raise awareness of this infection, which is more common than Down's syndrome, listeria and toxoplasmosis, and is theprimary preventable cause of childhood hearing loss. PMID:27295757

  4. Hepatitis C Virus.

    PubMed

    Kim, Arthur

    2016-09-01

    This issue provides a clinical overview of hepatitis C virus, focusing on transmission, prevention, screening, diagnosis, evaluation, and treatment. The content of In the Clinic is drawn from the clinical information and education resources of the American College of Physicians (ACP), including MKSAP (Medical Knowledge and Self-Assessment Program). Annals of Internal Medicine editors develop In the Clinic in collaboration with the ACP's Medical Education and Publishing divisions and with the assistance of additional science writers and physician writers. PMID:27595226

  5. Reemergence of Chikungunya Virus

    PubMed Central

    2014-01-01

    Chikungunya virus (CHIKV) is a mosquito-transmitted alphavirus that causes acute fever and acute and chronic musculoskeletal pain in humans. Since 2004, CHIKV has caused millions of cases of disease in the Indian Ocean region and has emerged in new areas, including Europe, the Middle East, and the Pacific region. The mosquito vectors for this virus are globally distributed in tropical and temperate zones, providing the opportunity for CHIKV to continue to expand into new geographic regions. In October 2013, locally acquired cases of CHIKV infection were identified on the Caribbean island of Saint Martin, signaling the arrival of the virus in the Western Hemisphere. In just 9 months, CHIKV has spread to 22 countries in the Caribbean and Central and South America, resulting in hundreds of thousands of cases. CHIKV disease can be highly debilitating, and large epidemics have severe economic consequences. Thus, there is an urgent need for continued research into the epidemiology, pathogenesis, prevention, and treatment of these infections. PMID:25078691

  6. Parainfluenza Virus Infection.

    PubMed

    Branche, Angela R; Falsey, Ann R

    2016-08-01

    Human parainfluenza viruses (HPIVs) are single-stranded, enveloped RNA viruses of the Paramyoviridaie family. There are four serotypes which cause respiratory illnesses in children and adults. HPIVs bind and replicate in the ciliated epithelial cells of the upper and lower respiratory tract and the extent of the infection correlates with the location involved. Seasonal HPIV epidemics result in a significant burden of disease in children and account for 40% of pediatric hospitalizations for lower respiratory tract illnesses (LRTIs) and 75% of croup cases. Parainfluenza viruses are associated with a wide spectrum of illnesses which include otitis media, pharyngitis, conjunctivitis, croup, tracheobronchitis, and pneumonia. Uncommon respiratory manifestations include apnea, bradycardia, parotitis, and respiratory distress syndrome and rarely disseminated infection. Immunity resulting from disease in childhood is incomplete and reinfection with HPIV accounts for 15% of respiratory illnesses in adults. Severe disease and fatal pneumonia may occur in elderly and immunocompromised adults. HPIV pneumonia in recipients of hematopoietic stem cell transplant (HSCT) is associated with 50% acute mortality and 75% mortality at 6 months. Though sensitive molecular diagnostics are available to rapidly diagnose HPIV infection, effective antiviral therapies are not available. Currently, treatment for HPIV infection is supportive with the exception of croup where the use of corticosteroids has been found to be beneficial. Several novel drugs including DAS181 appear promising in efforts to treat severe disease in immunocompromised patients, and vaccines to decrease the burden of disease in young children are in development. PMID:27486735

  7. [Ebola virus disease].

    PubMed

    Karwowska, Kornelia

    2015-01-01

    Ebola virus disease is a zoonosis causing high mortality epidemics in both human and animal populations. The virus belongs to the Filoviride family. It is composed of a single-strand of RNA. Morbidity foci appear in sub-Saharan Africa. The most probable reservoir are fruit bats, which are local delicacy. The most common route of infection is via mucosa or damaged skin. The spread of disease is rapid due to dietary habits, funeral rites and the insufficient supply of disposable equipment in hospitals. The incubation period of the disease ranges from 2 to 21 days. The beginning is abrupt, dominated by influenza-like symptoms. The disease is staggering with the predominant multi-organ failure and shock. Present-day epidemic symptoms from digestive system in the form of vomiting and diarrhoea are dominant. Currently, the research on vaccine and experimental drug is in progress. The virus is damaged by standard disinfectants used in health care units. Epidemic, which broke out in February 2014, caused by the most dangerous type Zaire, is the greatest of the existing. Morbidity and mortality is underestimated due to numerous unreported cases. PMID:25763588

  8. Marek's disease virus morphogenesis.

    PubMed

    Denesvre, Caroline

    2013-06-01

    Marek's disease virus (MDV) is a highly contagious virus that induces T-lymphoma in chicken. This viral infection still circulates in poultry flocks despite the use of vaccines. With the emergence of new virulent strains in the field over time, MDV remains a serious threat to the poultry industry. More than 40 yr after MDV identification as a herpesvirus, the visualization and purification of fully enveloped infectious particles remain a challenge for biologists. The various strategies used to detect such hidden particles by electron microscopy are reviewed herein. It is now generally accepted that the production of cell-free virions only occurs in the feather follicle epithelium and is associated with viral, cellular, or both molecular determinants expressed in this tissue. This tissue is considered the only source of efficient virus shedding into the environment and therefore the origin of successful transmission in birds. In other avian tissues or permissive cell cultures, MDV replication only leads to a very low number of intracellular enveloped virions. In the absence of detectable extracellular enveloped virions in cell culture, the nature of the transmitted infectious material and its mechanisms of spread from cell to cell remain to be deciphered. An attempt is made to bring together the current knowledge on MDV morphogenesis and spread, and new approaches that could help understand MDV morphogenesis are discussed. PMID:23901745

  9. Introducing Virological Concepts Using an Insect Virus.

    ERIC Educational Resources Information Center

    Sheppard, Roger F.

    1980-01-01

    A technique is presented which utilizes wax moth larvae in a laboratory investigation of an insect virus. Describes how an insect virus can be used to introduce undergraduate biology students to laboratory work on viruses and several virological concepts. (SA)

  10. NATIONAL RESPIRATORY AND ENTERIC VIRUS SURVEILLANCE SYSTEM

    EPA Science Inventory

    The National Respiratory and Enteric Virus Surveillance System is a lab based system which monitors temporal and geographic patterns associated with the detection of respiratory syncytial virus (RSV), human parainfluenza viruses (HPIV), respiratory and enteric adenoviruses, and r...

  11. Variant (Swine Origin) Influenza Viruses in Humans

    MedlinePlus

    ... What's this? Submit Button Past Newsletters Variant Influenza Viruses: Background and CDC Risk Assessment and Reporting Language: ... Background CDC Assessment Reporting Background On Variant Influenza Viruses Swine flu viruses do not normally infect humans. ...

  12. Dengue Virus May Bolster Zika's Attack

    MedlinePlus

    ... news/fullstory_159534.html Dengue Virus May Bolster Zika's Attack Prior exposure to this other mosquito-borne ... dengue fever virus may increase the severity of Zika virus, a new study says. Early stage laboratory ...

  13. Selecting Viruses for the Seasonal Influenza Vaccine

    MedlinePlus

    ... which viruses are selected for use in vaccine production? The influenza viruses in the seasonal flu vaccine ... to get a good vaccine virus for vaccine production? There are a number of factors that can ...

  14. Human Immunodeficiency Virus (HIV) Primary Infection

    MedlinePlus

    ... rashes clinical tools newsletter | contact Share | Human Immunodeficiency Virus (HIV) Primary Infection Information for adults A A ... weeks following exposure to HIV (the human immunodeficiency virus). Chronic infection with this virus can cause AIDS ( ...

  15. Epstein-Barr virus antibody test

    MedlinePlus

    Epstein-Barr virus antibody test is a blood test to detect antibodies to the Epstein-Barr virus ( EBV ). ... specialist looks for antibodies to the Epstein-Barr virus. In the first stages of an illness, little ...

  16. Dengue virus growth, purification, and fluorescent labeling.

    PubMed

    Zhang, Summer; Chan, Kuan Rong; Tan, Hwee Cheng; Ooi, Eng Eong

    2014-01-01

    The early events of the dengue virus life cycle involve virus binding, internalization, trafficking, and fusion. Fluorescently labeled viruses can be used to visualize these early processes. As dengue virus has 180 identical copies of the envelope protein attached to the membrane surface and is surrounded by a lipid membrane, amine-reactive (Alexa Fluor) or lipophilic (DiD) dyes can be used for virus labeling. These dyes are highly photostable and are ideal for studies involving cellular uptake and endosomal transport. To improve virus labeling efficiency and minimize the nonspecific labeling of nonviral proteins, virus concentration and purification precede fluorescent labeling of dengue viruses. Besides using these viruses for single-particle tracking, DiD-labeled viruses can also be used to distinguish serotype-specific from cross-neutralizing antibodies. Here the details of virus concentration, purification, virus labeling, applications, and hints of troubleshooting are described. PMID:24696327

  17. Le tetanos chez le grand enfant dans un hôpital pédiatrique à Yaoundé, Cameroun

    PubMed Central

    Ntoto Njiki Kinkela, Mina; Nguefack, Félicitée; Mbassi Awa, Hubert; Chelo, David; Enyama, Dominique; Mbollo Kobela, Marie; Koki Ndombo, Paul Olivier

    2012-01-01

    Le tétanos est évitable par la vaccination, mais peut survenir en cas d'une immunisation incomplète. Nous avons mené une étude sur les dossiers médicaux des enfants admis pour tétanos entre 2008-2009 au Centre Mère et Enfant de la Fondation Chantal BIYA à Yaoundé. Le but était d'analyser les circonstances de survenue et les manifestations cliniques du tétanos chez le grand enfant, afin de proposer des stratégies de prévention adaptées au contexte camerounais. Le statut vaccinal était inconnu chez un patient, les autres (80%) n'avaient pas reçu de rappel vaccinal. Les portes d'entrée étaient les plaies aux membres, l'une était secondaire à une injection médicamenteuse. Tous ont présenté le tétanos généralisé. Le décès était survenu chez un patient. Le tétanos n'est pas rare chez le grand enfant au Cameroun. Il se dégage ainsi la problématique des rappels vaccinaux. PMID:22514771

  18. Nuclear entry of DNA viruses

    PubMed Central

    Fay, Nikta; Panté, Nelly

    2015-01-01

    DNA viruses undertake their replication within the cell nucleus, and therefore they must first deliver their genome into the nucleus of their host cells. Thus, trafficking across the nuclear envelope is at the basis of DNA virus infections. Nuclear transport of molecules with diameters up to 39 nm is a tightly regulated process that occurs through the nuclear pore complex (NPC). Due to the enormous diversity of virus size and structure, each virus has developed its own strategy for entering the nucleus of their host cells, with no two strategies alike. For example, baculoviruses target their DNA-containing capsid to the NPC and subsequently enter the nucleus intact, while the hepatitis B virus capsid crosses the NPC but disassembles at the nuclear side of the NPC. For other viruses such as herpes simplex virus and adenovirus, although both dock at the NPC, they have each developed a distinct mechanism for the subsequent delivery of their genome into the nucleus. Remarkably, other DNA viruses, such as parvoviruses and human papillomaviruses, access the nucleus through an NPC-independent mechanism. This review discusses our current understanding of the mechanisms used by DNA viruses to deliver their genome into the nucleus, and further presents the experimental evidence for such mechanisms. PMID:26029198

  19. [Bovine immunodeficiency virus: short review].

    PubMed

    Bouillant, A M; Archambault, D

    1990-01-01

    A bovine visna-like virus was isolated by Van Der Maaten et al (1972) but it did not draw attention since, at that time, most efforts were directed towards research on bovine leukemia virus. However, new interest was shown on the bovine visna-like virus after the isolation of the human immunodeficiency virus (HIV), because of the urgent need for developing animal models for the acquired immunodeficiency syndrome (AIDS). The purpose of this paper is to describe the different stages of the identification of the bovine virus and to up-date knowledge about it. The bovine visna-like virus has recently been named the bovine immuno-deficiency-like virus (BIV) and is the sole bovine lentivirus known to-date. BIV shares morphologic, antigenic and genomic characteristics with other lentiviruses. It grows and induces large syncytia in vitro and generates virus-productive and latent infections in cell culture. It causes persistent infection and slow progressive disease in cattle and probably in sheep. As target cells of the virus are leukocytes, the type of which is unknown, perturbations of the immune system are expected. Consequently, BIV may potentiate the occurrence of secondary infections and play a role in retroviral, multiple infections. It is not oncogenic. Transmission appears to occur in cattle by contact, but evidence of transmission in human beings has not been shown. Finally, BIV may be a potential model in vitro and in vivo for HIV and AIDS. PMID:1963056

  20. Emergence of influenza A viruses.

    PubMed Central

    Webby, R J; Webster, R G

    2001-01-01

    Pandemic influenza in humans is a zoonotic disease caused by the transfer of influenza A viruses or virus gene segments from animal reservoirs. Influenza A viruses have been isolated from avian and mammalian hosts, although the primary reservoirs are the aquatic bird populations of the world. In the aquatic birds, influenza is asymptomatic, and the viruses are in evolutionary stasis. The aquatic bird viruses do not replicate well in humans, and these viruses need to reassort or adapt in an intermediate host before they emerge in human populations. Pigs can serve as a host for avian and human viruses and are logical candidates for the role of intermediate host. The transmission of avian H5N1 and H9N2 viruses directly to humans during the late 1990s showed that land-based poultry also can serve between aquatic birds and humans as intermediate hosts of influenza viruses. That these transmission events took place in Hong Kong and China adds further support to the hypothesis that Asia is an epicentre for influenza and stresses the importance of surveillance of pigs and live-bird markets in this area. PMID:11779380

  1. RECOVIR Software for Identifying Viruses

    NASA Technical Reports Server (NTRS)

    Chakravarty, Sugoto; Fox, George E.; Zhu, Dianhui

    2013-01-01

    Most single-stranded RNA (ssRNA) viruses mutate rapidly to generate a large number of strains with highly divergent capsid sequences. Determining the capsid residues or nucleotides that uniquely characterize these strains is critical in understanding the strain diversity of these viruses. RECOVIR (an acronym for "recognize viruses") software predicts the strains of some ssRNA viruses from their limited sequence data. Novel phylogenetic-tree-based databases of protein or nucleic acid residues that uniquely characterize these virus strains are created. Strains of input virus sequences (partial or complete) are predicted through residue-wise comparisons with the databases. RECOVIR uses unique characterizing residues to identify automatically strains of partial or complete capsid sequences of picorna and caliciviruses, two of the most highly diverse ssRNA virus families. Partition-wise comparisons of the database residues with the corresponding residues of more than 300 complete and partial sequences of these viruses resulted in correct strain identification for all of these sequences. This study shows the feasibility of creating databases of hitherto unknown residues uniquely characterizing the capsid sequences of two of the most highly divergent ssRNA virus families. These databases enable automated strain identification from partial or complete capsid sequences of these human and animal pathogens.

  2. Genome of Crocodilepox Virus

    PubMed Central

    Afonso, C. L.; Tulman, E. R.; Delhon, G.; Lu, Z.; Viljoen, G. J.; Wallace, D. B.; Kutish, G. F.; Rock, D. L.

    2006-01-01

    Here, we present the genome sequence, with analysis, of a poxvirus infecting Nile crocodiles (Crocodylus niloticus) (crocodilepox virus; CRV). The genome is 190,054 bp (62% G+C) and predicted to contain 173 genes encoding proteins of 53 to 1,941 amino acids. The central genomic region contains genes conserved and generally colinear with those of other chordopoxviruses (ChPVs). CRV is distinct, as the terminal 33-kbp (left) and 13-kbp (right) genomic regions are largely CRV specific, containing 48 unique genes which lack similarity to other poxvirus genes. Notably, CRV also contains 14 unique genes which disrupt ChPV gene colinearity within the central genomic region, including 7 genes encoding GyrB-like ATPase domains similar to those in cellular type IIA DNA topoisomerases, suggestive of novel ATP-dependent functions. The presence of 10 CRV proteins with similarity to components of cellular multisubunit E3 ubiquitin-protein ligase complexes, including 9 proteins containing F-box motifs and F-box-associated regions and a homologue of cellular anaphase-promoting complex subunit 11 (Apc11), suggests that modification of host ubiquitination pathways may be significant for CRV-host cell interaction. CRV encodes a novel complement of proteins potentially involved in DNA replication, including a NAD+-dependent DNA ligase and a protein with similarity to both vaccinia virus F16L and prokaryotic serine site-specific resolvase-invertases. CRV lacks genes encoding proteins for nucleotide metabolism. CRV shares notable genomic similarities with molluscum contagiosum virus, including genes found only in these two viruses. Phylogenetic analysis indicates that CRV is quite distinct from other ChPVs, representing a new genus within the subfamily Chordopoxvirinae, and it lacks recognizable homologues of most ChPV genes involved in virulence and host range, including those involving interferon response, intracellular signaling, and host immune response modulation. These data reveal

  3. Genome of crocodilepox virus.

    PubMed

    Afonso, C L; Tulman, E R; Delhon, G; Lu, Z; Viljoen, G J; Wallace, D B; Kutish, G F; Rock, D L

    2006-05-01

    Here, we present the genome sequence, with analysis, of a poxvirus infecting Nile crocodiles (Crocodylus niloticus) (crocodilepox virus; CRV). The genome is 190,054 bp (62% G+C) and predicted to contain 173 genes encoding proteins of 53 to 1,941 amino acids. The central genomic region contains genes conserved and generally colinear with those of other chordopoxviruses (ChPVs). CRV is distinct, as the terminal 33-kbp (left) and 13-kbp (right) genomic regions are largely CRV specific, containing 48 unique genes which lack similarity to other poxvirus genes. Notably, CRV also contains 14 unique genes which disrupt ChPV gene colinearity within the central genomic region, including 7 genes encoding GyrB-like ATPase domains similar to those in cellular type IIA DNA topoisomerases, suggestive of novel ATP-dependent functions. The presence of 10 CRV proteins with similarity to components of cellular multisubunit E3 ubiquitin-protein ligase complexes, including 9 proteins containing F-box motifs and F-box-associated regions and a homologue of cellular anaphase-promoting complex subunit 11 (Apc11), suggests that modification of host ubiquitination pathways may be significant for CRV-host cell interaction. CRV encodes a novel complement of proteins potentially involved in DNA replication, including a NAD(+)-dependent DNA ligase and a protein with similarity to both vaccinia virus F16L and prokaryotic serine site-specific resolvase-invertases. CRV lacks genes encoding proteins for nucleotide metabolism. CRV shares notable genomic similarities with molluscum contagiosum virus, including genes found only in these two viruses. Phylogenetic analysis indicates that CRV is quite distinct from other ChPVs, representing a new genus within the subfamily Chordopoxvirinae, and it lacks recognizable homologues of most ChPV genes involved in virulence and host range, including those involving interferon response, intracellular signaling, and host immune response modulation. These data

  4. Structure of Flexible Filamentous Plant Viruses

    SciTech Connect

    Kendall, Amy; McDonald, Michele; Bian, Wen; Bowles, Timothy; Baumgarten, Sarah C.; Shi, Jian; Stewart, Phoebe L.; Bullitt, Esther; Gore, David; Irving, Thomas C.; Havens, Wendy M.; Ghabrial, Said A.; Wall, Joseph S.; Stubbs, Gerald

    2008-10-23

    Flexible filamentous viruses make up a large fraction of the known plant viruses, but in comparison with those of other viruses, very little is known about their structures. We have used fiber diffraction, cryo-electron microscopy, and scanning transmission electron microscopy to determine the symmetry of a potyvirus, soybean mosaic virus; to confirm the symmetry of a potexvirus, potato virus X; and to determine the low-resolution structures of both viruses. We conclude that these viruses and, by implication, most or all flexible filamentous plant viruses share a common coat protein fold and helical symmetry, with slightly less than 9 subunits per helical turn.

  5. Computer virus information update CIAC-2301

    SciTech Connect

    Orvis, W.J.

    1994-01-15

    While CIAC periodically issues bulletins about specific computer viruses, these bulletins do not cover all the computer viruses that affect desktop computers. The purpose of this document is to identify most of the known viruses for the MS-DOS and Macintosh platforms and give an overview of the effects of each virus. The authors also include information on some windows, Atari, and Amiga viruses. This document is revised periodically as new virus information becomes available. This document replaces all earlier versions of the CIAC Computer virus Information Update. The date on the front cover indicates date on which the information in this document was extracted from CIAC`s Virus database.

  6. Geographical and Genetic Divergence Among Papaya ringspot virus Populations Within Hainan Province, China.

    PubMed

    Zhao, Hui; Jia, Rui Zong; Zhang, Yu-Liang; Zhu, Yun Judy; Zeng, Hui-Cai; Kong, Hua; McCafferty, Heather; Guo, An-Ping; Peng, Ming

    2016-08-01

    Papaya ringspot virus (PRSV) severely affects the global papaya industry. Transgenic papaya has been proven to have effective resistance to PRSV isolates from Hawaii, Thailand, Taiwan, and other countries. However, those transgenic cultivars failed to show resistance to Hainan Island isolates. Some 76 PRSV samples, representative of all traditional papaya planting areas across five cities (Wen Chang, n = 13; Cheng Mai, n = 14; Chang Jiang, n = 11; Le Dong, n = 25; and San Ya, n = 13) within Hainan Province, were investigated. Results revealed three genetic diversity groups (Hainan I, II, and III) that correlated with geographical distribution. Frequent mutations among PRSV isolates from Hainan were also observed. The high genetic divergence in PRSV isolates from Hainan is likely to be the cause of the failure of genetically modified papaya that targets sequence-specific virus. PMID:27070425

  7. Zika virus: epidemiology, clinical features and host-virus interactions.

    PubMed

    Hamel, Rodolphe; Liégeois, Florian; Wichit, Sineewanlaya; Pompon, Julien; Diop, Fodé; Talignani, Loïc; Thomas, Frédéric; Desprès, Philippe; Yssel, Hans; Missé, Dorothée

    2016-01-01

    Very recently, Zika virus (ZIKV) has gained a medical importance following the large-scale epidemics in South Pacific and Latin America. This paper reviews information on the epidemiology and clinical features of Zika disease with a particular emphasis on the host-virus interactions that contribute to the pathogenicity of ZIKV in humans. PMID:27012221

  8. Parainfluenza Virus 5 Expressing the G Protein of Rabies Virus Protects Mice after Rabies Virus Infection

    PubMed Central

    Huang, Ying; Chen, Zhenhai; Huang, Junhua

    2014-01-01

    Rabies remains a major public health threat around the world. Once symptoms appear, there is no effective treatment to prevent death. In this work, we tested a recombinant parainfluenza virus 5 (PIV5) strain expressing the glycoprotein (G) of rabies (PIV5-G) as a therapy for rabies virus infection: we have found that PIV5-G protected mice as late as 6 days after rabies virus infection. PIV5-G is a promising vaccine for prevention and treatment of rabies virus infection. PMID:25552723

  9. Uukuniemi Virus as a Tick-Borne Virus Model

    PubMed Central

    Mazelier, Magalie; Rouxel, Ronan Nicolas; Zumstein, Michael; Mancini, Roberta; Bell-Sakyi, Lesley

    2016-01-01

    ABSTRACT In the last decade, novel tick-borne pathogenic phleboviruses in the family Bunyaviridae, all closely related to Uukuniemi virus (UUKV), have emerged on different continents. To reproduce the tick-mammal switch in vitro, we first established a reverse genetics system to rescue UUKV with a genome close to that of the authentic virus isolated from the Ixodes ricinus tick reservoir. The IRE/CTVM19 and IRE/CTVM20 cell lines, both derived from I. ricinus, were susceptible to the virus rescued from plasmid DNAs and supported production of the virus over many weeks, indicating that infection was persistent. The glycoprotein GC was mainly highly mannosylated on tick cell-derived viral progeny. The second envelope viral protein, GN, carried mostly N-glycans not recognized by the classical glycosidases peptide-N-glycosidase F (PNGase F) and endoglycosidase H (Endo H). Treatment with β-mercaptoethanol did not impact the apparent molecular weight of GN. On viruses originating from mammalian BHK-21 cells, GN glycosylations were exclusively sensitive to PNGase F, and the electrophoretic mobility of the protein was substantially slower after the reduction of disulfide bonds. Furthermore, the amount of viral nucleoprotein per focus forming unit differed markedly whether viruses were produced in tick or BHK-21 cells, suggesting a higher infectivity for tick cell-derived viruses. Together, our results indicate that UUKV particles derived from vector tick cells have glycosylation and structural specificities that may influence the initial infection in mammalian hosts. This study also highlights the importance of working with viruses originating from arthropod vector cells in investigations of the cell biology of arbovirus transmission and entry into mammalian hosts. IMPORTANCE Tick-borne phleboviruses represent a growing threat to humans globally. Although ticks are important vectors of infectious emerging diseases, previous studies have mainly involved virus stocks

  10. Le médicament générique au Maroc: le point de vue du consommateur

    PubMed Central

    Zaoui, Sanaa; Hakkou, Farid; Filali, Houda; Khabal, Youssef; Tazi, Illias; Mahmal, Lahoucine

    2013-01-01

    Introduction Le médicament générique est souvent une origine de préjugés négatifs et de méfiance chez les professionnels de santé et les patients. Ceci pourrait être dû à plusieurs facteurs entre autre le manque des connaissances du patient sur ces médicaments. Le but de notre étude était d’évaluer l'information du consommateur sur les médicaments génériques et apprécier leur utilisation de ces médicaments. Méthodes Il s'agit d'une étude transversale réalisée de Janvier à Mars 2010 auprès de 251 sujets. Un questionnaire comprenant dix questions fermées a été utilisé. Les questions concernaient l’évaluation des connaissances sur les médicaments génériques, les sources d'information, le degré de confiance et d'information des patients sur ces médicaments. Une analyse descriptive simple des différentes variables a été réalisée. Résultats Dans notre étude, 126 sujets (50,2%) ont répondu connaître les médicaments génériques. Parmi eux, 52,3% les utilisaient et 67,4% estimaient qu'ils étaient insuffisamment informés sur ces médicaments. Les cadres supérieurs et les étudiants ont représenté la catégorie qui utilisait le plus les médicaments génériques (respectivement dans 40,9% et 25,7%) et qui était la mieux informée (respectivement dans 61,9% et 23,81%). Le faible coût a été la principale motivation d'utilisation du médicament générique (93,9%). Les médias ont représenté la première source d'information (59,5%). Après sensibilisation, 88,8% des sujets qui ne connaissaient pas le médicament générique ont été favorable à son utilisation. Conclusion Une promotion efficace par une politique d'information soutenue auprès des consommateurs et par des mesures incitatrices à la prescription et à la délivrance du générique par les médecins et les pharmaciens, pourront améliorer l'utilisation de ces médicaments dans notre pays. PMID:24009794

  11. Virioplankton: Viruses in Aquatic Ecosystems†

    PubMed Central

    Wommack, K. Eric; Colwell, Rita R.

    2000-01-01

    The discovery that viruses may be the most abundant organisms in natural waters, surpassing the number of bacteria by an order of magnitude, has inspired a resurgence of interest in viruses in the aquatic environment. Surprisingly little was known of the interaction of viruses and their hosts in nature. In the decade since the reports of extraordinarily large virus populations were published, enumeration of viruses in aquatic environments has demonstrated that the virioplankton are dynamic components of the plankton, changing dramatically in number with geographical location and season. The evidence to date suggests that virioplankton communities are composed principally of bacteriophages and, to a lesser extent, eukaryotic algal viruses. The influence of viral infection and lysis on bacterial and phytoplankton host communities was measurable after new methods were developed and prior knowledge of bacteriophage biology was incorporated into concepts of parasite and host community interactions. The new methods have yielded data showing that viral infection can have a significant impact on bacteria and unicellular algae populations and supporting the hypothesis that viruses play a significant role in microbial food webs. Besides predation limiting bacteria and phytoplankton populations, the specific nature of virus-host interaction raises the intriguing possibility that viral infection influences the structure and diversity of aquatic microbial communities. Novel applications of molecular genetic techniques have provided good evidence that viral infection can significantly influence the composition and diversity of aquatic microbial communities. PMID:10704475

  12. Pathogenic Pseudorabies Virus, China, 2012

    PubMed Central

    Yu, Xiuling; Zhou, Zhi; Hu, Dongmei; Zhang, Qian; Han, Tao; Li, Xiaoxia; Gu, Xiaoxue; Yuan, Lin; Zhang, Shuo; Wang, Baoyue; Qu, Ping; Liu, Jinhua; Zhai, Xinyan

    2014-01-01

    In 2012, an unprecedented large-scale outbreak of disease in pigs in China caused great economic losses to the swine industry. Isolates from pseudorabies virus epidemics in swine herds were characterized. Evidence confirmed that the pathogenic pseudorabies virus was the etiologic agent of this epidemic. PMID:24377462

  13. Groundnut Ringspot Virus in Florida

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Tospoviruses in vegetable crops are difficult to manage due to a shortage of basic information about the viruses and their vectors. This is especially true for the recently detected Groundnut ringspot virus (GRSV). This publication presents all current knowledge of GRSV in Florida....

  14. TOTAL CULTURABLE VIRUS QUANTAL ASSAY

    EPA Science Inventory

    This chapter describes a quantal method for assaying culturable human enteric viruses from water matrices. The assay differs from the plaque assay described in Chapter 10 (December 1987 Revision) in that it is based upon the direct microscopic viewing of cells for virus-induced ...

  15. Paper Models Illustrating Virus Symmetry.

    ERIC Educational Resources Information Center

    McCarthy, D. A.

    1990-01-01

    Instructions are given for constructing two models, one to illustrate the general principles of symmetry in T=1, T=3, and T=4 viruses, and the other to illustrate the disposition of protein subunits in the T=3 plant viruses and the picornaviruses. (Author/CW)

  16. Tobacco ringspot virus in Rubus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Tobacco ringspot virus (TRSV) has a broad host range among woody and perennial plants and has been reported from blackberry but not from red or black raspberry. The virus has been detected in blackberry in the southeastern United States with a single report from blackberry in British Columbia, Cana...

  17. Oncolytic virus therapy for cancer

    PubMed Central

    Goldufsky, Joe; Sivendran, Shanthi; Harcharik, Sara; Pan, Michael; Bernardo, Sebastian; Stern, Richard H; Friedlander, Philip; Ruby, Carl E; Saenger, Yvonne; Kaufman, Howard L

    2013-01-01

    The use of oncolytic viruses to treat cancer is based on the selection of tropic tumor viruses or the generation of replication selective vectors that can either directly kill infected tumor cells or increase their susceptibility to cell death and apoptosis through additional exposure to radiation or chemotherapy. In addition, viral vectors can be modified to promote more potent tumor cell death, improve the toxicity profile, and/or generate host antitumor immunity. A variety of viruses have been developed as oncolytic therapeutics, including adenovirus, vaccinia virus, herpesvirus, coxsackie A virus, Newcastle disease virus, and reovirus. The clinical development of oncolytic viral therapy has accelerated in the last few years, with several vectors entering clinical trials for a variety of cancers. In this review, current strategies to optimize the therapeutic effectiveness and safety of the major oncolytic viruses are discussed, and a summary of current clinical trials is provided. Further investigation is needed to characterize better the clinical impact of oncolytic viruses, but there are increasing data demonstrating the potential promise of this approach for the treatment of human and animal cancers. PMID:27512656

  18. Unraveling hepatitis C virus structure.

    PubMed

    Fauvelle, Catherine; Felmlee, Daniel J; Baumert, Thomas F

    2014-04-01

    The high variability and the limited knowledge of the structure of the hepatitis C virus (HCV) envelope glycoproteins (GP) are challenging hurdles for vaccine design. Recently, Kong et al. published a new model of HCV E2 GP structure in Science, revealing a globular structure, starkly contrasting from the extended model of class II fusion proteins from other Flaviviridae viruses. PMID:24626133

  19. Genetic Diversity of Toscana Virus

    PubMed Central

    Collao, Ximena; Palacios, Gustavo; Sanbonmatsu-Gámez, Sara; Pérez-Ruiz, Mercedes; Negredo, Ana I.; Navarro-Marí, José-María; Grandadam, Marc; Aransay, Ana Maria; Lipkin, W. Ian; Tenorio, Antonio

    2009-01-01

    Distribution of Toscana virus (TOSV) is evolving with climate change, and pathogenicity may be higher in nonexposed populations outside areas of current prevalence (Mediterranean Basin). To characterize genetic diversity of TOSV, we determined the coding sequences of isolates from Spain and France. TOSV is more diverse than other well-studied phleboviruses (e.g.,Rift Valley fever virus). PMID:19331735

  20. Virus Detection and Field Management

    Technology Transfer Automated Retrieval System (TEKTRAN)

    There are two primary pathogens of Oat – Crown Rust and the Luteoviruses Barley and Cereal Yellow Dwarf Virus (BYDV and CYDV). These viruses can only be transmitted by aphids, are limited to the vascular system in infected plants and can lead to severe stunting and a concomitant yield loss. In 200...

  1. Swine Influenza Virus: Emerging Understandings

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Introduction: In March-April 2009, a novel pandemic H1N1 emerged in the human population in North America [1]. The gene constellation of the emerging virus was demonstrated to be a combination of genes from swine influenza A viruses (SIV) of North American and Eurasian lineages that had never before...

  2. Virology of hepatitis C virus.

    PubMed

    Fang, J W; Chow, V; Lau, J Y

    1997-11-01

    Advances in molecular biology techniques have allowed the cloning of HCV and the characterization of this virus. This article provides a short summary of our current knowledge on the genomic organization of HCV, the implications of its genetic heterogeneous nature, and the probable replication strategy of this virus. PMID:15560054

  3. Zika Virus Infection and Microcephaly.

    PubMed

    Millichap, J Gordon

    2016-01-01

    A Task Force established by the Brazil Ministry of Health investigated the possible association of microcephaly with Zika virus infection during pregnancy and a registry for microcephaly cases among women suspected to have had Zika virus infection during pregnancy. PMID:27004142

  4. Antiviral immunity and virus vaccines

    Technology Transfer Automated Retrieval System (TEKTRAN)

    As obligate intracellular organisms, viruses have co-evolved with their respective host species, which in turn have evolved diverse and sophisticated capabilities to protect themselves against viral infections and their associated diseases. Viruses have also evolved a remarkable variety of strategie...

  5. Neonatal herpes simplex virus.

    PubMed

    Berardi, Alberto; Lugli, Licia; Rossi, Cecilia; Maria, Chiara Laguardia; Guidotti, Isotta; Gallo, Claudio; Ferrari, Fabrizio

    2011-10-01

    Herpes simplex virus is an important cause of neonatal infection, which can lead to death or long-term disabilities. Rarely in utero, the transmission frequently occurs during delivery. The disease may be disseminated, localized to the central nervous system, or involving skin, eye and/or mouth. Mortality rates markedly decreased with high-dose antiviral treatment. Diagnosis of neonatal infection is based on viral isolation from ulcerated vesicles or by scarifying mucocutaneous lesions. Recently polymerase chain reaction plays a central role for both viral detection (skin, mucosal, cerebrospinal fluid samples) and response to therapy. Vertical transmission may be decreased by prophylactic antiviral treatment. PMID:21942600

  6. Feline immunodeficiency virus infection.

    PubMed

    Pedersen, N C; Yamamoto, J K; Ishida, T; Hansen, H

    1989-05-01

    Feline immunodeficiency virus (FIV) (formerly feline T-lymphotropic lentivirus or FTLV) was first isolated from a group of cats in Petaluma, California in 1986. The virus is a typical lentivirus in gross and structural morphology. It replicates preferentially but not exclusively in feline T-lymphoblastoid cells, where it causes a characteristic cytopathic effect. The major structural proteins are 10, 17 (small gag), 28 (major core), 31 (endonuclease?), 41 (transmembrane?), 52 (core precursor polyprotein), 54/62 (reverse transcriptase?), and 110/130 (major envelope) kilodaltons in size. The various proteins are antigenically distinguishable from those of other lentiviruses, although serum from EIAV-infected horses will cross-react with some FIV antigens. Kittens experimentally infected with FIV manifest a transient (several days to 2 weeks) fever and neutropenia beginning 4 to 8 weeks after inoculation. This is associated with a generalized lymphadenopathy that persists for up to 9 months. Most cats recover from this initial phase of the disease and become lifelong carriers of the virus. Complete recovery does not occur to any extent in nature or in the laboratory setting. One experimentally infected cat died from a myeloproliferative disorder several months after infection. The terminal AIDS-like phase of the illness has been seen mainly in naturally infected cats. It appears a year or more following the initial infection in an unknown proportion of infected animals. FIV has been identified in cats from all parts of the world. It is most prevalent in high density populations of free roaming cats (feral and pet), and is very uncommon in closed purebred catteries. Male cats are twice as likely to become infected as females. Older male cats adopted as feral or stray animals are at the highest risk of infection, therefore. The infection rate among freely roaming cats rises throughout life, and reaches levels ranging from less than 1% to 12% or more depending on the

  7. Sunshine virus in Australian pythons.

    PubMed

    Hyndman, Timothy H; Shilton, Cathy M; Doneley, Robert J T; Nicholls, Philip K

    2012-12-28

    Sunshine virus is a recently discovered novel paramyxovirus that is associated with illness in snakes. It does not phylogenetically cluster within either of the two currently accepted paramyxoviral subfamilies. It is therefore only distantly related to the only other known genus of reptilian paramyxoviruses, Ferlavirus, which clusters within the Paramyxovirinae subfamily. Clinical and diagnostic aspects associated with Sunshine virus are as yet undescribed. The objective of this paper was to report the clinical presentation, virus isolation, PCR testing and pathology associated with Sunshine virus infection. Clinical records and samples from naturally occurring cases were obtained from two captive snake collections and the archives of a veterinary diagnostic laboratory. The clinical signs that are associated with Sunshine virus infection are localised to the neurorespiratory systems or are non-specific (e.g. lethargy, inappetence). Out of 15 snakes that were infected with Sunshine virus (detected in any organ by either virus isolation or PCR), the virus was isolated from four out of ten (4/10) sampled brains, 3/10 sampled lungs and 2/7 pooled samples of kidney and liver. In these same 15 snakes, PCR was able to successfully detect Sunshine virus in fresh-frozen brain (11/11), kidney (7/8), lung (8/11) and liver (5/8); and various formalin-fixed paraffin-embedded tissues (7/8). During a natural outbreak of Sunshine virus in a collection of 32 snakes, the virus could be detected in five out of 39 combined oral-cloacal swabs that were collected from 23 of these snakes over a 105 day period. All snakes that were infected with Sunshine virus were negative for reovirus and ferlavirus by PCR. Snakes infected with Sunshine virus reliably exhibited hindbrain white matter spongiosis and gliosis with extension to the surrounding grey matter and neuronal necrosis evident in severe cases. Five out of eight infected snakes also exhibited mild bronchointerstitial pneumonia

  8. New aspects of influenza viruses.

    PubMed Central

    Shaw, M W; Arden, N H; Maassab, H F

    1992-01-01

    Influenza virus infections continue to cause substantial morbidity and mortality with a worldwide social and economic impact. The past five years have seen dramatic advances in our understanding of viral replication, evolution, and antigenic variation. Genetic analyses have clarified relationships between human and animal influenza virus strains, demonstrating the potential for the appearance of new pandemic reassortants as hemagglutinin and neuraminidase genes are exchanged in an intermediate host. Clinical trials of candidate live attenuated influenza virus vaccines have shown the cold-adapted reassortants to be a promising alternative to the currently available inactivated virus preparations. Modern molecular techniques have allowed serious consideration of new approaches to the development of antiviral agents and vaccines as the functions of the viral genes and proteins are further elucidated. The development of techniques whereby the genes of influenza viruses can be specifically altered to investigate those functions will undoubtedly accelerate the pace at which our knowledge expands. PMID:1310439

  9. Virus assembly, allostery, and antivirals

    PubMed Central

    Zlotnick, Adam; Mukhopadhyay, Suchetana

    2010-01-01

    Assembly of virus capsids and surface proteins must be regulated to ensure that the resulting complex is an infectious virion. Here we examine assembly of virus capsids, focusing on hepatitis B virus and bacteriophage MS2, and formation of glycoproteins in the alphaviruses. These systems are structurally and biochemically well-characterized and are simplest-case paradigms of self-assembly. Published data suggest that capsid and glycoprotein assembly is subject to allosteric regulation, that is, regulation at the level of conformational change. The hypothesis that allostery is a common theme in viruses suggests that deregulation of capsid and glycoprotein assembly by small molecule effectors will be an attractive antiviral strategy, as has been demonstrated with hepatitis B virus. PMID:21163649

  10. Marine Viruses: Truth or Dare

    NASA Astrophysics Data System (ADS)

    Breitbart, Mya

    2012-01-01

    Over the past two decades, marine virology has progressed from a curiosity to an intensely studied topic of critical importance to oceanography. At concentrations of approximately 10 million viruses per milliliter of surface seawater, viruses are the most abundant biological entities in the oceans. The majority of these viruses are phages (viruses that infect bacteria). Through lysing their bacterial hosts, marine phages control bacterial abundance, affect community composition, and impact global biogeochemical cycles. In addition, phages influence their hosts through selection for resistance, horizontal gene transfer, and manipulation of bacterial metabolism. Recent work has also demonstrated that marine phages are extremely diverse and can carry a variety of auxiliary metabolic genes encoding critical ecological functions. This review is structured as a scientific "truth or dare," revealing several well-established "truths" about marine viruses and presenting a few "dares" for the research community to undertake in future studies.

  11. Giant viruses come of age.

    PubMed

    Fischer, Matthias G

    2016-06-01

    Viruses with genomes up to a few megabases in length are a common occurrence in nature, even though they have escaped our notice until recently. These giant viruses infect mainly single-celled eukaryotes and isolation efforts concentrating on amoebal hosts alone have spawned hundreds of viral isolates, featuring viruses with previously unseen virion morphologies and the largest known viral genomes and particles. One of the challenges that lie ahead is to analyze and categorize the available data and to establish an approved classification system that reflects the evolutionary relationships and biological properties of these viruses. Extensive sampling of Acanthamoeba-infecting mimiviruses and initial characterization of their virophage parasites have provided a first blueprint of the genetic diversity and composition of a giant virus clade that will facilitate the taxonomic grouping of these fascinating microorganisms. PMID:26999382

  12. Le consentement libre et éclairé aux soins en psychiatrie

    PubMed Central

    Neilson, Grainne; Chaimowitz, Gary

    2015-01-01

    Résumé Le patient a le droit d’être informé sur les soins de santé qui lui sont proposés et de participer activement à la prise de décisions relativement à ces soins. Le respect de la dignité et de l’autonomie de la personne passe par le respect de son droit de prendre des décisions à propos de ses soins psychiatriques, notamment de refuser un traitement, pour autant qu’elle soit apte à prendre des décisions. Il importe que le psychiatre connaisse les fondements éthiques du consentement libre et éclairé et les exigences prévues par le droit en cette matière, y compris la jurisprudence. Le consentement n’est pas immuable, pouvant changer avec le temps, au fil de l’évolution des conditions et des circonstances. Par conséquent, le consentement doit être un processus continu.

  13. 4. Historic American Buildings Survey, Arthur W. LeBoeuf, Photographer, 1937 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. Historic American Buildings Survey, Arthur W. LeBoeuf, Photographer, 1937 DETAIL OF WINDOW BREAKING INTO PEDIMENT. - First Congregational Church, 301 Benefit Street, Providence, Providence County, RI

  14. The JPL 'long ephemeris', DE102/LE51

    NASA Technical Reports Server (NTRS)

    Standish, E. M., Jr.

    1983-01-01

    A number of applications exist in astronomical research for planetary and lunar ephemerides covering an extended length of time. This paper discusses such a set of ephemerides, DE102/LE51, produced at JPL, covering the time 1411 B.C. to 3001 A.D. The ephemerides are dynamically self-consistent, in that the equations of motion were integrated simultaneously. They also represent the most accurately known positions covering such a time span. They have already been used by a number of different users in a variety of different applications.

  15. Snow in Castile-León: trends and variability

    NASA Astrophysics Data System (ADS)

    Merino, A.; Campos, L.; López, L.; García-Ortega, E.; Sánchez, J. L.; Marcos, J. L.; Guerrero-Higueras, A. M.

    2012-04-01

    The location of Castile and León, inside the Iberian Peninsula, in the Northwestern quadrant, determines, in large measure, the climatic conditions of its territory, granting it very characteristic traits, mostly in the mountainous areas. It is important to note that during a large part of the year, the region is under the influence of Jet Stream, and thus, gives way to very diverse dynamic situations, which turn into different and heterogeneous types of weather. So, in many areas of the region, especially in the most elevated areas, these synoptic and mesoscale situations generate snow precipitation. We should point out that snowfall is one of the principal meteorological risks of Castile and León. Thus, on average, in some mountainous areas there are more than 40 events of snowfall registered annually, with the month of January being the month in which the highest frequency of snowfall appears. The social repercussions of this snowfall are represented in the isolation of places, essentially mountainous, highways being blocked, increase in traffic accidents, etc. As proof of this, it is this type of episode that receives ample coverage by the media, which has a linear relationship with the social perception of risk. As such, the objective of the current work is to analyze the annual trend of days with snow in the different meteorological stations pertaining to AEMET placed in the Community. The period of study is from 1960-2010. Additionally, we have also evaluated trends in annual days of freezing temperature and annual absolute minimum temperature, with the objective of facilitating a meteorological interpretation of the trends obtained on days with snowfall. Finally, the results show that in the majority of stations, a significant negative trend in days with snowfall and annual days with freezing temperatures, and a positive trend in annual absolute minimum temperatures. However, we observed variability in the different regions in the area of study

  16. Sequence heterogeneity of murine acquired immunodeficiency syndrome virus: the role of endogenous virus.

    PubMed

    Gayama, S; Vaupel, B A; Kanagawa, O

    1995-05-01

    A defective murine leukemia virus is the causative agent of murine acquired immunodeficiency syndrome (MAIDS). We have cloned cDNAs from both virus infected and non-infected cells using the PCR methods with primers corresponding to the franking sequence of the unique p12 gag gene. Sequence analysis of these cDNA clones revealed: (i) the presence of endogenous virus related to MAIDS virus in C57BL/6 mice, (ii) B cell lineage specific expression of endogenous virus and (iii) extensive heterogeneity of MAIDS virus recovered from virus infected cells due to the recombination of the related viruses (defective pathogenic virus, ecotropic virus and endogenous virus). These findings suggest that the creation of virus variants in infected cells may play an important role in virus pathogenesis and escape from immune attack during the development of MAIDS. PMID:7547712

  17. Collaborative evaluation of a method for the detection of Norwalk virus in shellfish tissues by PCR.

    PubMed Central

    Atmar, R L; Neill, F H; Woodley, C M; Manger, R; Fout, G S; Burkhardt, W; Leja, L; McGovern, E R; Le Guyader, F; Metcalf, T G; Estes, M K

    1996-01-01

    A multicenter, collaborative trial was performed to evaluate the reliability and reproducibility of a previously described method for the detection of Norwalk virus in shellfish tissues with the PCR (R.L. Atmar, F. H. Neill, J. L. Romalde, F. Le Guyader, C. M. Woodley, T. G. Metcalf, and M. K. Estes, Appl. Environ. Microbiol. 61:3014-3018, 1995). Virus was added to the stomachs and hepatopancreatic tissues of oysters or hard-shell clams in the control laboratory, the samples were shipped to the participating laboratories, and viral nucleic acids were extracted and then detected by reverse transcription-PCR. The sensitivity and specificity of the assay were 85 and 91%, respectively, when results were determined by visual inspection of ethidium bromide-stained agarose gels; the test sensitivity and specificity improved to 87 and 100%, respectively, after confirmation by hybridization with a digoxigenin-labeled, virus-specific probe. We have demonstrated that this method can be implemented successfully by several laboratories to detect Norwalk virus in shellfish tissues. PMID:8572702

  18. Dengue virus vaccine development.

    PubMed

    Yauch, Lauren E; Shresta, Sujan

    2014-01-01

    Dengue virus (DENV) is a significant cause of morbidity and mortality in tropical and subtropical regions, causing hundreds of millions of infections each year. Infections range from asymptomatic to a self-limited febrile illness, dengue fever (DF), to the life-threatening dengue hemorrhagic fever/dengue shock syndrome (DHF/DSS). The expanding of the habitat of DENV-transmitting mosquitoes has resulted in dramatic increases in the number of cases over the past 50 years, and recent outbreaks have occurred in the United States. Developing a dengue vaccine is a global health priority. DENV vaccine development is challenging due to the existence of four serotypes of the virus (DENV1-4), which a vaccine must protect against. Additionally, the adaptive immune response to DENV may be both protective and pathogenic upon subsequent infection, and the precise features of protective versus pathogenic immune responses to DENV are unknown, complicating vaccine development. Numerous vaccine candidates, including live attenuated, inactivated, recombinant subunit, DNA, and viral vectored vaccines, are in various stages of clinical development, from preclinical to phase 3. This review will discuss the adaptive immune response to DENV, dengue vaccine challenges, animal models used to test dengue vaccine candidates, and historical and current dengue vaccine approaches. PMID:24373316

  19. Hepatitis E Virus Infection

    PubMed Central

    Dalton, Harry R.; Abravanel, Florence; Izopet, Jacques

    2014-01-01

    SUMMARY Hepatitis E virus (HEV) infection is a worldwide disease. An improved understanding of the natural history of HEV infection has been achieved within the last decade. Several reservoirs and transmission modes have been identified. Hepatitis E is an underdiagnosed disease, in part due to the use of serological assays with low sensitivity. However, diagnostic tools, including nucleic acid-based tests, have been improved. The epidemiology and clinical features of hepatitis E differ between developing and developed countries. HEV infection is usually an acute self-limiting disease, but in developed countries it causes chronic infection with rapidly progressive cirrhosis in organ transplant recipients, patients with hematological malignancy requiring chemotherapy, and individuals with HIV. HEV also causes extrahepatic manifestations, including a number of neurological syndromes and renal injury. Acute infection usually requires no treatment, but chronic infection should be treated by reducing immunosuppression in transplant patients and/or the use of antiviral therapy. In this comprehensive review, we summarize the current knowledge about the virus itself, as well as the epidemiology, diagnostics, natural history, and management of HEV infection in developing and developed countries. PMID:24396139

  20. APOBECs and Virus Restriction

    PubMed Central

    Harris, Reuben S.; Dudley, Jaquelin P.

    2015-01-01

    The APOBEC family of single-stranded DNA cytosine deaminases comprises a formidable arm of the vertebrate innate immune system. Pre-vertebrates express a single APOBEC, whereas some mammals produce as many as eleven enzymes. The APOBEC3 subfamily displays both copy number variation and polymorphisms, consistent with ongoing pathogenic pressures. These enzymes restrict the replication of many DNA-based parasites, such as exogenous viruses and endogenous transposable elements. APOBEC1 and activation-induced cytosine deaminase (AID) have specialized functions in RNA editing and antibody gene diversification, respectively, whereas APOBEC2 and APOBEC4 appear to have different functions. Nevertheless, the APOBEC family protects against both periodic viral zoonoses as well as exogenous and endogenous parasite replication. This review highlights viral pathogens that are restricted by APOBEC enzymes, but manage to escape through unique mechanisms. The sensitivity of viruses that lack counterdefense measures highlights the need to develop APOBEC-enabling small molecules as a new class of anti-viral drugs. PMID:25818029

  1. Comparison of Immunohistochemistry and Virus Isolation for Diagnosis of West Nile Virus

    PubMed Central

    Ellis, Angela E.; Mead, Daniel G.; Allison, Andrew B.; Gibbs, Samantha E. J.; Gottdenker, Nicole L.; Stallknecht, David E.; Howerth, Elizabeth W.

    2005-01-01

    Immunohistochemistry and virus isolation were performed on 1,057 birds. Immunohistochemistry, virus isolation, or both found 325 birds to be West Nile virus positive. Of these, 271 were positive by both methods. These results indicate that virus isolation and immunohistochemistry are approximately equal in their ability to detect West Nile virus. PMID:15956415

  2. A single vertebrate DNA virus protein disarms invertebrate immunity to RNA virus infection

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Virus-host interactions drive a remarkable diversity of immune responses and countermeasures. While investigating virus-invertebrate host interactions we found that two RNA viruses with broad host ranges, vesicular stomatitis virus (VSV) and Sindbis virus (SINV), were unable to infect certain Lepido...

  3. Infectious vaccinia virus recombinants that express hepatitis B virus surface antigen

    NASA Astrophysics Data System (ADS)

    Smith, Geoffrey L.; Mackett, Michael; Moss, Bernard

    1983-04-01

    Potential live vaccines against hepatitis B virus have been produced. The coding sequence for hepatitis B virus surface antigen (HBsAg) has been inserted into the vaccinia virus genome under control of vaccinia virus early promoters. Cells infected with these vaccinia virus recombinants synthesize and excrete HBsAg and vaccinated rabbits rapidly produce antibodies to HBsAg.

  4. Live-attenuated influenza A virus vaccines using a B virus backbone

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The currently FDA-licensed live attenuated influenza virus vaccine contains a trivalent mixture of types A (H1N1 and H3N2) and B vaccine viruses. The two A virus vaccines have the backbone of a cold-adapted influenza A virus and the B virus vaccine has the six backbone segments derived from a cold-...

  5. Le genre Tunga Jarocki, 1838 (Siphonaptera : Tungidae). I – Taxonomie, phylogénie, écologie, rôle pathogène

    PubMed Central

    Beaucournu, J.-C.; Degeilh, B.; Mergey, T.; Muñoz-Leal, S.; González-Acuña, D.

    2012-01-01

    Pour la première fois, les 12 espèces actuellement décrites dans le genre Tunga sont étudiées sur le plan de la taxonomie et de la répartition. Divers aspects de leur biologie et leur rôle pathogène sont également envisagés, et en particulier leur phylogénie, leur chorologie, leur phénologie, leur sexe-ratio et leurs dermecos. PMID:23193514

  6. Safe Computing: An Overview of Viruses.

    ERIC Educational Resources Information Center

    Wodarz, Nan

    2001-01-01

    A computer virus is a program that replicates itself, in conjunction with an additional program that can harm a computer system. Common viruses include boot-sector, macro, companion, overwriting, and multipartite. Viruses can be fast, slow, stealthy, and polymorphic. Anti-virus products are described. (MLH)

  7. Dissecting the mode of maize chlorotic mottle virus transmission (Tombusviridae: Machlomovirus) by Frankliniella williamsi (Thysanoptera: Thripidae).

    PubMed

    Cabanas, D; Watanabe, S; Higashi, C H V; Bressan, A

    2013-02-01

    Maize chlorotic mottle virus (MCMV) (Tombusviridae: Machlomovirus) has been recorded in Hawaii (Kauai Island) since the early 1990s and has since become one of the most widespread corn viruses in the Hawaiian Islands. In the United States Mainland, MCMV has been reported to be transmitted by six different species of chrysomelid beetles, including the western corn rootworm, Diabrotica virgifera virgifera LeConte. However, none of these beetle species have been reported in Hawaii where the corn thrips, Frankliniella williamsi Hood (Thysanoptera: Thripidae) has been identified to be the main vector. In this study, we developed leaf disk transmission assays and real time reverse transcription-polymerase chain reaction to examine the mode of MCMV transmission by the corn thrips. We showed that thrips transmitted the virus with no evidence for latent periods. Both larvae and adults transmitted the virus for up to 6 d after acquisition, with decreasing rates of transmission as time progressed. There was no evidence that adult thrips that acquired the virus as larvae were competent vectors. Real time reverse-transcription polomerase chain reaction assays showed that viral load was depleted from the vector's body after thrips had access to healthy plant tissue. Depletion of viral load was also observed when thrips matured from larvae to adults. Thrips were able to transmit MCMV after acquisition and inoculation access periods of 3 h. However, transmission efficiency increased with longer acquisition and inoculation access periods. Taken altogether our data suggests that corn thrips transmit MCMV in a semipersistent manner. To our knowledge, this is the first work reporting evidence of a plant virus transmitted semipersistently by thrips. PMID:23448010

  8. The IFITMs Inhibit Zika Virus Replication.

    PubMed

    Savidis, George; Perreira, Jill M; Portmann, Jocelyn M; Meraner, Paul; Guo, Zhiru; Green, Sharone; Brass, Abraham L

    2016-06-14

    Zika virus has emerged as a severe health threat with a rapidly expanding range. The IFITM family of restriction factors inhibits the replication of a broad range of viruses, including the closely related flaviruses West Nile virus and dengue virus. Here, we show that IFITM1 and IFITM3 inhibit Zika virus infection early in the viral life cycle. Moreover, IFITM3 can prevent Zika-virus-induced cell death. These results suggest that strategies to boost the actions and/or levels of the IFITMs might be useful for inhibiting a broad range of emerging viruses. PMID:27268505

  9. Defining Life: The Virus Viewpoint

    NASA Astrophysics Data System (ADS)

    Forterre, Patrick

    2010-04-01

    Are viruses alive? Until very recently, answering this question was often negative and viruses were not considered in discussions on the origin and definition of life. This situation is rapidly changing, following several discoveries that have modified our vision of viruses. It has been recognized that viruses have played (and still play) a major innovative role in the evolution of cellular organisms. New definitions of viruses have been proposed and their position in the universal tree of life is actively discussed. Viruses are no more confused with their virions, but can be viewed as complex living entities that transform the infected cell into a novel organism—the virus—producing virions. I suggest here to define life (an historical process) as the mode of existence of ribosome encoding organisms (cells) and capsid encoding organisms (viruses) and their ancestors. I propose to define an organism as an ensemble of integrated organs (molecular or cellular) producing individuals evolving through natural selection. The origin of life on our planet would correspond to the establishment of the first organism corresponding to this definition.

  10. Marburg Virus Reverse Genetics Systems

    PubMed Central

    Schmidt, Kristina Maria; Mühlberger, Elke

    2016-01-01

    The highly pathogenic Marburg virus (MARV) is a member of the Filoviridae family and belongs to the group of nonsegmented negative-strand RNA viruses. Reverse genetics systems established for MARV have been used to study various aspects of the viral replication cycle, analyze host responses, image viral infection, and screen for antivirals. This article provides an overview of the currently established MARV reverse genetic systems based on minigenomes, infectious virus-like particles and full-length clones, and the research that has been conducted using these systems. PMID:27338448

  11. Hepatitis C virus. A review.

    PubMed Central

    Tang, E.

    1991-01-01

    Hepatitis C virus has been shown to be responsible for most cases of posttransfusion hepatitis, as well as for sporadic non-A, non-B viral hepatitis. Hepatitis C virus has also been implicated in the development of primary hepatocellular carcinoma, autoimmune hepatitis, and fulminant viral hepatitis. Although the role of the parenteral transmission of hepatitis C virus is well established, its route of transmission in cases of sporadic infection remains unclear. Sexual transmission is suspected but not confirmed. Recent work regarding treatment has shown interferon alfa to be effective, but the discontinuation of therapy is associated with a 50% relapse rate. PMID:1656611

  12. Marburg Virus Reverse Genetics Systems.

    PubMed

    Schmidt, Kristina Maria; Mühlberger, Elke

    2016-01-01

    The highly pathogenic Marburg virus (MARV) is a member of the Filoviridae family and belongs to the group of nonsegmented negative-strand RNA viruses. Reverse genetics systems established for MARV have been used to study various aspects of the viral replication cycle, analyze host responses, image viral infection, and screen for antivirals. This article provides an overview of the currently established MARV reverse genetic systems based on minigenomes, infectious virus-like particles and full-length clones, and the research that has been conducted using these systems. PMID:27338448

  13. Polymerase Activity of Pichinde Virus

    PubMed Central

    Carter, Michael F.; Biswal, Nilambar; Rawls, William E.

    1974-01-01

    Pichinde virus, a member of the arenavirus group, was examined for polymerase activity. Purified virus was found to contain RNA-dependent RNA polymerase but not RNA-dependent DNA polymerase activity. Since RNase but neither DNase nor actinomycin D inhibited the endogenous polymerase reaction, RNA of the virus appeared to be used as the template. The divalent cations Mg2+ and Mn2+ were required for optimal reactivity. The RNA product was partially resistant to RNase and the resistant portion had a sedimentation coefficient of 22 to 26S in sucrose gradients. PMID:4132669

  14. Xenotropic Murine Leukemia Virus-related Virus (XMRV) Backgrounder

    Cancer.gov

    Researchers have not found evidence that XMRV causes any diseases in humans or in animals. The presence of an infectious agent, such as a virus, in diseased tissue does not mean that the agent causes the disease.

  15. Respiratory Viruses Other than Influenza Virus: Impact and Therapeutic Advances

    PubMed Central

    Nichols, W. Garrett; Peck Campbell, Angela J.; Boeckh, Michael

    2008-01-01

    Summary: Though several antivirals have been developed and marketed to treat influenza virus infections, the development of antiviral agents with clinical activity against other respiratory viruses has been more problematic. Here we review the epidemiology of respiratory viral infections in immunocompetent and immunocompromised hosts, examine the evidence surrounding the currently available antivirals for respiratory viral infections other than influenza, highlight those that are in the pipeline, and discuss the hurdles for development of such agents. PMID:18400797

  16. Génotypes du virus de l'hépatite B et marqueurs évolutifs des patients porteurs chroniques de l'AgHBs à Bujumbura

    PubMed Central

    Ntagirabiri, Rénovat; Munezero, Belyse; Nahimana, Caritas; Ndabaneze, Evariste

    2016-01-01

    Introduction L'infection par le virus de l'hépatite B (VHB) est une affection grave suite à ses complications notamment la cirrhose et le carcinome hépatocellulaire (CHC). Les génotypes du VHB influent beaucoup sur son évolution et sur l'efficacité du traitement. Le but était d’évaluer les génotypes du VHB et les profils évolutifs des patients porteurs chroniques de l'AgHBs. Méthodes Étude transversale, menée au Centre hospitalo-universitaire de Kamenge et au Centre des maladies du tube digestif et du foie « CEMADIF » entre Juin 2013 et Mai 2014. Le génotypage, les dosages quantitatifs de l'AgHBe et de l'ADN virale B ont été réalisés au Laboratoire Cerba, Cergy Pontoise, France. L’évaluation de la fibrose était faite par le Fibrotest ou le FibroScan. Résultats Au total, 143 patients, 52,4% de sexe masculin, âge moyen 38,1 ans ont été inclus. Selon les marqueurs évolutifs, 112 patients (78,3%) avaient un AgHBe négatif. Quant à la charge virale, 106 patients (74,2%) avaient une virémie inférieure à 2000UI/ml et une fibrose minime inférieure à 7kpa selon le FibroScan. Parmi eux, 13 malades avaient un ADN du VHB indétectable (<20UI/ml). Les autres 37 patients (26,8%) avaient une charge virale supérieure à 2000UI/ml et parmi eux, 31 avaient un AgHBe positif (>0,8UI/ml). Il a été possible de déterminer le génotype chez 51 patients qui avaient une virémie assez élevée pour permettre techniquement ce dosage. Ces patients avaient tous un génotype A. Conclusion Le génotype A du VHB est le plus fréquent à Bujumbura. Il est associé à un portage inactif élevé. PMID:27222687

  17. Human immunodeficiency virus endocrinopathy

    PubMed Central

    Sinha, Uma; Sengupta, Nilanjan; Mukhopadhyay, Prasanta; Roy, Keshab Sinha

    2011-01-01

    Human immunodeficiency virus (HIV) endocrinopathy encompasses a broad spectrum of disorders. Almost all the endocrine organs are virtually affected by HIV infection. HIV can directly alter glandular function. More commonly secondary endocrine dysfunction occurs due to opportunistic infections and neoplasms in immunocompromised state. The complex interaction between HIV infection and endocrine system may be manifested as subtle biochemical and hormonal perturbation to overt glandular failure. Antiretroviral therapy as well as other essential medications often result in adverse endocrinal consequences. Apart from adrenal insufficiency, hypogonadism, diabetes and bone loss, AIDS wasting syndrome and HIV lipodystrophy need special reference. Endocrinal evaluation should proceed as in other patients with suspected endocrine dysfunction. Available treatment options have been shown to improve quality of life and long-term mortality in AIDS patients. PMID:22028995

  18. Zika virus infections.

    PubMed

    de Laval, F; Leparc-Goffart, I; Meynard, J-B; Daubigny, H; Simon, F; Briolant, S

    2016-05-01

    Since its discovery in 1947 in Uganda, the Zika virus (ZIKV) remained in the shadows emerging in 2007 in Micronesia, where hundreds of dengue-like syndromes were reported. Then, in 2013-2014, it was rife in French Polynesia, where the first neurological effects were observed. More recently, its arrival in Brazil was accompanied by an unusually high number of children with microcephaly born to mothers infected with ZIKV during the first trimester of pregnancy. In 2016, the World Health Organization declared ZIKV infection to be a public health emergency and now talks about a ZIKV pandemic. This review aims to summarize the current knowledge about ZIKV infection, successively addressing its transmission, epidemiology, clinical aspects, diagnosis, treatment, and prevention before discussing some perspectives. PMID:27412976

  19. Varicella-zoster virus.

    PubMed Central

    Arvin, A M

    1996-01-01

    Varicella-zoster virus (VZV) is a ubiquitous human alphaherpesvirus that causes varicella (chicken pox) and herpes zoster (shingles). Varicella is a common childhood illness, characterized by fever, viremia, and scattered vesicular lesions of the skin. As is characteristic of the alphaherpesviruses, VZV establishes latency in cells of the dorsal root ganglia. Herpes zoster, caused by VZV reactivation, is a localized, painful, vesicular rash involving one or adjacent dermatomes. The incidence of herpes zoster increases with age or immunosuppression. The VZV virion consists of a nucleocapsid surrounding a core that contains the linear, double-stranded DNA genome; a protein tegument separates the capsid from the lipid envelope, which incorporates the major viral glycoproteins. VZV is found in a worldwide geographic distribution but is more prevalent in temperate climates. Primary VZV infection elicits immunoglobulin G (IgG), IgM, and IgA antibodies, which bind to many classes of viral proteins. Virus-specific cellular immunity is critical for controlling viral replication in healthy and immunocompromised patients with primary or recurrent VZV infections. Rapid laboratory confirmation of the diagnosis of varicella or herpes zoster, which can be accomplished by detecting viral proteins or DNA, is important to determine the need for antiviral therapy. Acyclovir is licensed for treatment of varicella and herpes zoster, and acyclovir, valacyclovir, and famciclovir are approved for herpes zoster. Passive antibody prophylaxis with varicella-zoster immune globulin is indicated for susceptible high-risk patients exposed to varicella. A live attenuated varicella vaccine (Oka/Merck strain) is now recommended for routine childhood immunization. PMID:8809466

  20. Characterization of a new bacteriocin from Lactobacillus plantarum LE5 and LE27 isolated from ensiled corn.

    PubMed

    Amortegui, Jairo; Rodríguez-López, Alexander; Rodríguez, Deicy; Carrascal, Ana K; Alméciga-Díaz, Carlos J; Melendez, Adelina del P; Sánchez, Oscar F

    2014-04-01

    Bacteriocins are low molecular peptides with antimicrobial activity, which are of great interest as food bio-preservatives and for treating diseases caused by pathogenic bacteria. In this study, we present the characterization of bacteriocins produced by Lactobacillus plantarum LE5 and LE27 isolated from ensiled corn. Bacteriocins were purified through ammonium sulfate precipitation and double dialysis by using 12- and 1-kDa membranes. Bacteriocins showed activity against Listeria innocua, Listeria monocytogenes, and Enteroccocus faecalis. Molecular weight was estimated through Tricine-SDS-PAGE and overloading the gel onto Mueller-Hinton agar seeded with L. monocytogenes, showing an inhibition zone between 5 and 10 kDa. NanoLC-MS/MS analysis allowed the identification of UPF0291 protein (UniProtKB/Swiss-Prot Q88VI7), which is also presented in other lactic acid bacteria without assigned function. Ab initio modeling showed it has an α-helix-rich structure and a large positive-charged region. Bacteriocins were stable between 4 and 121 °C and pH 2 and 12, and the activity was inhibited by SDS and proteases. Mode of action assay suggests that the bacteriocin causes of target microorganism. Taken together, these results describe a possible new class IIa bacteriocin produced by L. plantarum, which has a wide stability to physicochemical conditions, and that could be used as an alternative for the control of foodborne diseases. PMID:24532444

  1. Use of Mobile Testing System PeLe for Developing Language Skills

    ERIC Educational Resources Information Center

    Titova, Svetlana

    2015-01-01

    One of the objectives of this paper is to investigate the pedagogical impact of both the mobile testing system PeLe (Norway, HiST) and the enquiry-based learning approach on language skills development in the context of mobile-assisted learning. The research aims to work out a methodological framework of PeLe implementation into the language…

  2. CoLeMo: A Collaborative Learning Environment for UML Modelling

    ERIC Educational Resources Information Center

    Chen, Weiqin; Pedersen, Roger Heggernes; Pettersen, Oystein

    2006-01-01

    This paper presents the design, implementation, and evaluation of a distributed collaborative UML modelling environment, CoLeMo. CoLeMo is designed for students studying UML modelling. It can also be used as a platform for collaborative design of software. We conducted formative evaluations and a summative evaluation to improve the environment and…

  3. MODeLeR: A Virtual Constructivist Learning Environment and Methodology for Object-Oriented Design

    ERIC Educational Resources Information Center

    Coffey, John W.; Koonce, Robert

    2008-01-01

    This article contains a description of the organization and method of use of an active learning environment named MODeLeR, (Multimedia Object Design Learning Resource), a tool designed to facilitate the learning of concepts pertaining to object modeling with the Unified Modeling Language (UML). MODeLeR was created to provide an authentic,…

  4. Understanding the recognition of Lewis X by anti-Le(x) monoclonal antibodies.

    PubMed

    Moore, Christopher J; Auzanneau, France-Isabelle

    2013-10-24

    The recognition of the Le(x) antigen by the anti-Le(x) monoclonal antibody (mAb) SH1 was studied by ELISA using a panel of 4″-modified Le(x) analogues. We confirmed that these analogues maintained the stacked conformation adopted by natural Le(x) antigen using 1D ROESY experiments and measuring intramolecular distances. Our binding studies show that the 4-OH″ of galactose behaves as an H-bond donor to an electronegative amino acid side chain in the SH1 binding site. While removal of this H-bond leads to reduced inhibition, disturbing the hydrophobic α face of the β-galactosyl residue leads to complete loss of binding to SH1. We compared our results to the crystal structure of the Fab fragment of anti-Le(x) mAb 291-2G3-A complexed with Le(x) (PDB entry 1UZ8 ). While no H-bond involving the 4-OH″ was described, hydrophobic interactions between a tryptophan residue and the β-galactoside α face are observed. We conclude that the hydrophobic α face that is uniquely displayed by β-galactosyl residues is essential to the recognition of the Le(x) antigen by anti-Le(x) antibodies. PMID:24059473

  5. Novel vaccines against influenza viruses

    PubMed Central

    Kang, Sang-Moo; Song, Jae-Min; Compans, Richard W.

    2011-01-01

    Killed and live attenuated influenza virus vaccines are effective in preventing and curbing the spread of influenza epidemics when the strains present in the vaccines are closely matched with the predicted epidemic strains. These vaccines are primarily targeted to induce immunity to the variable major target antigen, hemagglutinin (HA) of influenza virus. However, current vaccines are not effective in preventing the emergence of new pandemic or highly virulent viruses. New approaches are being investigated to develop universal influenza virus vaccines as well as to apply more effective vaccine delivery methods. Conserved vaccine targets including the influenza M2 ion channel protein and HA stalk domains are being developed using recombinant technologies to improve the level of cross protection. In addition, recent studies provide evidence that vaccine supplements can provide avenues to further improve current vaccination. PMID:21968298

  6. About Human Parainfluenza Viruses (HPIVs)

    MedlinePlus

    ... Overview Laboratory Diagnosis HPIV Seasons Resources & References About Human Parainfluenza Viruses (HPIVs) Recommend on Facebook Tweet Share ... 6348 Email CDC-INFO U.S. Department of Health & Human Services HHS/Open USA.gov Top

  7. Herpes Simplex Virus (Cold Sores)

    MedlinePlus

    ... the skin, eyes, and mouth. This is a life-threatening infection that can lead to permanent brain damage or even death. Herpes simplex viruses also cause encephalitis, an infection of the brain. ...

  8. Peste des Petits Ruminants Virus.

    PubMed

    Baron, M D; Diallo, A; Lancelot, R; Libeau, G

    2016-01-01

    Peste des petits ruminants virus (PPRV) causes a severe contagious disease of sheep and goats and has spread extensively through the developing world. Because of its disproportionately large impact on the livelihoods of low-income livestock keepers, and the availability of effective vaccines and good diagnostics, the virus is being targeted for global control and eventual eradication. In this review we examine the origin of the virus and its current distribution, and the factors that have led international organizations to conclude that it is eradicable. We also review recent progress in the molecular and cellular biology of the virus and consider areas where further research is required to support the efforts being made by national, regional, and international bodies to tackle this growing threat. PMID:27112279

  9. Viruses of eukaryotice green algae

    SciTech Connect

    Van Etten, J.L.

    1989-01-01

    The primary objective of our research was to develop the Chlorella-PBCV-1 virus system so that it can be used as a model system for studying gene expression in a photosynthetic eukaryote. We have made considerable progress and have learned much about PBCV-1 and its replication cycle. In addition, several significant discoveries were made in the last 3 to 4 years. These discoveries include: (i) the finding that morphologically similar, plaque forming, dsDNA containing viruses are common in nature and can be isolated readily from fresh water, (ii) the finding that all of these Chlorella viruses contain methylated bases which range in concentration from 0.1% to 47.5% m{sup 5}dC and 0 to 37% m{sup 6}dA and (iii) the discovery that infection with at least some of these viruses induces the appearance of DNA modification/restriction systems. 26 refs.

  10. Lactate dehydrogenase-elevating virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This book chapter describes the taxonomic classification of Lactate dehydrogenase-elevating virus (LDV). Included are: host, genome, classification, morphology, physicochemical and physical properties, nucleic acid, proteins, lipids, carbohydrates, geographic range, phylogenetic properties, biologic...

  11. Live viruses to treat cancer

    PubMed Central

    Donnelly, Oliver; Harrington, Kevin; Melcher, Alan; Pandha, Hardev

    2013-01-01

    Viruses that selectively replicate in cancer cells, leading to the death of the cell, are being studied for their potential as cancer therapies. Some of these viruses are naturally occurring but cause little if any illness in humans; others have been engineered to make them specifically able to kill cancer cells while sparing normal cells. These oncolytic viruses may be selective for cancer cells because viral receptors are over-expressed on the surface of cancer cells or because antiviral pathways are distorted in cancer cells. Additionally, when oncolytic viruses kill cancer cells, it can stimulate an antitumour immune response from the host that can enhance efficacy. Numerous early phase trials of at least six oncolytic viruses have been reported with no evidence of concerning toxicity either as single agents or in combination with chemotherapies and radiotherapy. Three oncolytic viruses have reached randomized testing in cancer patients; reolysin in head and neck cancer and JX594 in hepatocellular cancers, while results from the first-phase III trial of T-vec in metastatic melanoma are expected shortly. PMID:23824333

  12. A DNA Virus of Drosophila

    PubMed Central

    Unckless, Robert L.

    2011-01-01

    Little is known about the viruses infecting most species. Even in groups as well-studied as Drosophila, only a handful of viruses have been well-characterized. A viral metagenomic approach was used to explore viral diversity in 83 wild-caught Drosophila innubila, a mushroom feeding member of the quinaria group. A single fly that was injected with, and died from, Drosophila C Virus (DCV) was added to the sample as a control. Two-thirds of reads in the infected sample had DCV as the best BLAST hit, suggesting that the protocol developed is highly sensitive. In addition to the DCV hits, several sequences had Oryctes rhinoceros Nudivirus, a double-stranded DNA virus, as a best BLAST hit. The virus associated with these sequences was termed Drosophila innubila Nudivirus (DiNV). PCR screens of natural populations showed that DiNV was both common and widespread taxonomically and geographically. Electron microscopy confirms the presence of virions in fly fecal material similar in structure to other described Nudiviruses. In 2 species, D. innubila and D. falleni, the virus is associated with a severe (∼80–90%) loss of fecundity and significantly decreased lifespan. PMID:22053195

  13. The NASA-LeRC wind turbine sound prediction code

    NASA Technical Reports Server (NTRS)

    Viterna, L. A.

    1981-01-01

    Since regular operation of the DOE/NASA MOD-1 wind turbine began in October 1979 about 10 nearby households have complained of noise from the machine. Development of the NASA-LeRC with turbine sound prediction code began in May 1980 as part of an effort to understand and reduce the noise generated by MOD-1. Tone sound levels predicted with this code are in generally good agreement with measured data taken in the vicinity MOD-1 wind turbine (less than 2 rotor diameters). Comparison in the far field indicates that propagation effects due to terrain and atmospheric conditions may be amplifying the actual sound levels by about 6 dB. Parametric analysis using the code has shown that the predominant contributions to MOD-1 rotor noise are: (1) the velocity deficit in the wake of the support tower; (2) the high rotor speed; and (3) off column operation.

  14. Design of Multidimensional Shinnar-Le Roux RF Pulses

    PubMed Central

    Ma, Chao; Liang, Zhi-Pei

    2014-01-01

    Purpose To generalize the conventional Shinnar-Le Roux (SLR) method for the design of multidimensional RF pulses. Methods Using echo-planar gradients, the multidimensional RF pulse design problem was converted into a series of 1D polynomial design problems. Each of the 1D polynomial design problems was solved efficiently. B0 inhomogeneity compensation and design of spatial-spectral pulses were also considered. Results The proposed method was used to design 2D excitation and refocusing pulses. The results were validated through Bloch equation simulation and experiments on a 3.0 T scanner. Large-tip-angle, equiripple-error, multidimensional excitation was achieved with ripple levels closely matching the design specifications. Conclusion The conventional SLR method can be extended to design multidimensional RF pulses. The proposed method achieves almost equiripple excitation errors, allows easy control of the tradeoff among design parameters, and is computationally efficient. PMID:24578212

  15. The ERDA/LeRC Photovoltaic Systems Test Facility

    NASA Technical Reports Server (NTRS)

    Forestieri, A. F.

    1978-01-01

    The ERDA/LeRC Photovoltaic Systems Test Facility (STF) provides a vital support function to the overall ERDA National Solar Photovoltaic Program. It allows preliminary investigation and checkout of components, subsystems, and complete photovoltaic systems before installation in actual service. The STF can also be used to determine optimum system configurations and operating modes. A facility description is presented, taking into account the solar cell array, the energy storage equipment, the power conditioning equipment, electric utility distribution network and loads, and instrumentation and data acquisition systems. Safety procedures which have been set up for maintenance and inspection of the solar array are discussed. Attention is also given to a number of investigations regarding the effect of environmental factors on solar cell array operation.

  16. An Overview-NASA LeRC Structures Program

    NASA Technical Reports Server (NTRS)

    Zaretsky, Erwin V.

    1997-01-01

    The Structures and Acoustics Division of the NASA Lewis Research Center has its genesis dating back to 1943. It has been an independent Division at Lewis since 1979. Its two primary capabilities are performance and life analysis of static and dynamic systems such as those found in aircraft and spacecraft propulsion systems and experimental verification of these analyses. Research is conducted in-house, through university grants and contracts, and through cooperative programs with industry. Our work directly supports NASA's Advanced Subsonic Technology (AST), Smart Green Engine, Fast Quiet Engine, High-Temperature Materials and Processing (HiTEMP), Hybrid Hyperspeed Propulsion, Rotorcraft, High-Speed Research (HSR), and Aviation Safety Program (AvSP). A general overview is given discussing these programs and other technologies that are being developed at NASA LeRC.

  17. PC viruses: How do they do that

    SciTech Connect

    Pichnarczyk, K.

    1992-07-01

    The topic of PC Viruses has been an issue for a number of years now. They've been reported in every major newspaper, tabloids, television and radio. People from all fields get viruses: government, private sector businesses, home computers, schools, computer software suppliers. A definition is proposed to introduce the virus phenomenon. Virus authors come from a variety of communities. Motives and ideologies of authors are discussed, and examples of viruses are offered. Also mentioned is the growing number of viruses developed, isolated, and never distributed to the public at large, but kept within the antivirus research community. Virus examples are offered as well. Viruses are distributed not only through bulletin boards and shareware, but also from areas previously assumed to be safe, including the threat of receiving a virus through a standard in-house function, such as an in-house hardware maintenance shop. Three categories of viruses are presented: File Infecter viruses, Boot Sector Infecters, and the new category of Directory Entry Infecter virus. Also discussed are crossover viruses, that is, viruses which utilize a variety of techniques to ensure survival. An explanation of what is occurring within every stage of various viruses is given. Replication strategies common to all three types is noted, mainly the two different replication strategies of memory resident infecters and active selection infecters. A detailed definition, description and application of a stealth virus is presented. Detection strategies are discussed as each topic in this section is completed; a high level schemata of the operation of various virus detection programs ispresented. Since most eradication today is done using virus detection/eradication software, this paper attempts to reveal the techniques used by these packages.Included in the paper is the topic of manual eradication.

  18. PC viruses: How do they do that?

    SciTech Connect

    Pichnarczyk, K.

    1992-07-01

    The topic of PC Viruses has been an issue for a number of years now. They`ve been reported in every major newspaper, tabloids, television and radio. People from all fields get viruses: government, private sector businesses, home computers, schools, computer software suppliers. A definition is proposed to introduce the virus phenomenon. Virus authors come from a variety of communities. Motives and ideologies of authors are discussed, and examples of viruses are offered. Also mentioned is the growing number of viruses developed, isolated, and never distributed to the public at large, but kept within the antivirus research community. Virus examples are offered as well. Viruses are distributed not only through bulletin boards and shareware, but also from areas previously assumed to be safe, including the threat of receiving a virus through a standard in-house function, such as an in-house hardware maintenance shop. Three categories of viruses are presented: File Infecter viruses, Boot Sector Infecters, and the new category of Directory Entry Infecter virus. Also discussed are crossover viruses, that is, viruses which utilize a variety of techniques to ensure survival. An explanation of what is occurring within every stage of various viruses is given. Replication strategies common to all three types is noted, mainly the two different replication strategies of memory resident infecters and active selection infecters. A detailed definition, description and application of a stealth virus is presented. Detection strategies are discussed as each topic in this section is completed; a high level schemata of the operation of various virus detection programs ispresented. Since most eradication today is done using virus detection/eradication software, this paper attempts to reveal the techniques used by these packages.Included in the paper is the topic of manual eradication.

  19. Dysfonctionnements radio-induits du transport colique chez le rat

    NASA Astrophysics Data System (ADS)

    François, A.; Lebrun, F.; Ksas, B.; Aigueperse, J.; Gourmelon, P.; MacNaughton, W. K.; Griffiths, N. M.

    1998-04-01

    The symptom commonly associated with whole body irradiation is diarrhoea, a still quite obscure phenomenon, which leads to decreased chance of cure of irradiated people. The aim of this study was to provide evidence for dysfunction of intestinal water and electrolyte transport regulation by the enteric nervous system after exposure to ionising radiation. This study shows decreased capacity of enteric nervous system to influence colonic transport 3days after irradiation, correlated to a diminished response to a neurotransmitter: serotonin. Radio-induced diarrhea may result from epithelial structural injury but also from impaired regulatory processes of intestinal transport. L'un des symptômes majeurs d'une irradiation corporelle totale ou abdominale est l'apparition de diarrhées, dont les causes sont encore mal connues, et qui mettent en jeu le pronostique vital de l'individu irradié. Cette étude vise à mettre en évidence l'atteinte de la régulation du transport intestinal d'eau et d'électrolytes par les rayonnements ionisants. On observe une diminution de la capacité du système nerveux entérique à influencer le transport colique 3jours après irradiation, corrélée à une diminution de la réponse épithéliale à un neurotransmetteur : la sérotonine. Les diarrhées radio-induites résulteraient d'une atteinte structurelle de l'épithélium mais également des processus de régulation du transport intestinal.

  20. Neptune's Discovery: Le Verrier, Adams, and the Assignment of Credit

    NASA Astrophysics Data System (ADS)

    Sheehan, William

    2011-01-01

    As one of the most significant achievements of 19th century astronomy, the discovery of Neptune has been the subject of a vast literature. A large part of this literature--beginning with the period immediately after the optical discovery in Berlin--has been the obsession with assigning credit to the two men who attempted to calculate the planet's position (and initially this played out against the international rivalry between France and England). Le Verrier and Adams occupied much different positions in the Scientific Establishments of their respective countries; had markedly different personalities; and approached the investigation using different methods. A psychiatrist and historian of astronomy tries to provide some new contexts to the familiar story of the discovery of Neptune, and argues that the personalities of these two men played crucial roles in their approaches to the problem they set themselves and the way others reacted to their stimuli. Adams had features of high-functioning autism, while Le Verrier's domineering, obsessive, orderly personality--though it allowed him to be immensely productive--eventually led to serious difficulties with his peers (and an outright revolt). Though it took extraordinary smarts to calculate the position of Neptune, the discovery required social skills that these men lacked--and thus the process to discovery was more bumbling and adventitious than it might have been. The discovery of Neptune occurred at a moment when astronomy was changing from that of heroic individuals to team collaborations involving multiple experts, and remains an object lesson in the sociological aspects of scientific endeavor.

  1. Endosomal Maturation, Rab7 GTPase and Phosphoinositides in African Swine Fever Virus Entry

    PubMed Central

    Cuesta-Geijo, Miguel A.; Galindo, Inmaculada; Hernáez, Bruno; Quetglas, Jose Ignacio; Dalmau-Mena, Inmaculada; Alonso, Covadonga

    2012-01-01

    Here we analyzed the dependence of African swine fever virus (ASFV) infection on the integrity of the endosomal pathway. Using confocal immunofluorescence with antibodies against viral capsid proteins, we found colocalization of incoming viral particles with early endosomes (EE) during the first minutes of infection. Conversely, viral capsid protein was not detected in acidic late endosomal compartments, multivesicular bodies (MVBs), late endosomes (LEs) or lysosomes (LY). Using an antibody against a viral inner core protein, we found colocalization of viral cores with late compartments from 30 to 60 minutes postinfection. The absence of capsid protein staining in LEs and LYs suggested that virus desencapsidation would take place at the acid pH of these organelles. In fact, inhibitors of intraluminal acidification of endosomes caused retention of viral capsid staining virions in Rab7 expressing endosomes and more importantly, severely impaired subsequent viral protein production. Endosomal acidification in the first hour after virus entry was essential for successful infection but not thereafter. In addition, altering the balance of phosphoinositides (PIs) which are responsible of the maintenance of the endocytic pathway impaired ASFV infection. Early infection steps were dependent on the production of phosphatidylinositol 3-phosphate (PtdIns3P) which is involved in EE maturation and multivesicular body (MVB) biogenesis and on the interconversion of PtdIns3P to phosphatidylinositol 3, 5-biphosphate (PtdIns(3,5)P2). Likewise, GTPase Rab7 activity should remain intact, as well as processes related to LE compartment physiology, which are crucial during early infection. Our data demonstrate that the EE and LE compartments and the integrity of the endosomal maturation pathway orchestrated by Rab proteins and PIs play a central role during early stages of ASFV infection. PMID:23133661

  2. Zika Virus Infection and Zika Fever: Frequently Asked Questions

    MedlinePlus

    ... Updated: 25 March 2016 ABOUT ZIKA What is Zika virus infection? Zika virus infection is caused by the ... possible to characterize the disease better. How is Zika virus transmitted? Zika virus is transmitted to people through ...

  3. Overexpression of the tomato pollen receptor kinase LePRK1 rewires pollen tube growth to a blebbling mode

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The tubular growth of a pollen tube cell is crucial for the sexual reproduction of flowering plants. LePRK1 is a pollen-specific and plasma membrane–localized receptor-like kinase from tomato (Solanum lycopersicum). LePRK1 interacts with another receptor, LePRK2, and with KINASE PARTNER PROTEIN (KPP...

  4. Quantitative nanoscale electrostatics of viruses

    NASA Astrophysics Data System (ADS)

    Hernando-Pérez, M.; Cartagena-Rivera, A. X.; Lošdorfer Božič, A.; Carrillo, P. J. P.; San Martín, C.; Mateu, M. G.; Raman, A.; Podgornik, R.; de Pablo, P. J.

    2015-10-01

    Electrostatics is one of the fundamental driving forces of the interaction between biomolecules in solution. In particular, the recognition events between viruses and host cells are dominated by both specific and non-specific interactions and the electric charge of viral particles determines the electrostatic force component of the latter. Here we probe the charge of individual viruses in liquid milieu by measuring the electrostatic force between a viral particle and the Atomic Force Microscope tip. The force spectroscopy data of co-adsorbed φ29 bacteriophage proheads and mature virions, adenovirus and minute virus of mice capsids is utilized for obtaining the corresponding density of charge for each virus. The systematic differences of the density of charge between the viral particles are consistent with the theoretical predictions obtained from X-ray structural data. Our results show that the density of charge is a distinguishing characteristic of each virus, depending crucially on the nature of the viral capsid and the presence/absence of the genetic material.Electrostatics is one of the fundamental driving forces of the interaction between biomolecules in solution. In particular, the recognition events between viruses and host cells are dominated by both specific and non-specific interactions and the electric charge of viral particles determines the electrostatic force component of the latter. Here we probe the charge of individual viruses in liquid milieu by measuring the electrostatic force between a viral particle and the Atomic Force Microscope tip. The force spectroscopy data of co-adsorbed φ29 bacteriophage proheads and mature virions, adenovirus and minute virus of mice capsids is utilized for obtaining the corresponding density of charge for each virus. The systematic differences of the density of charge between the viral particles are consistent with the theoretical predictions obtained from X-ray structural data. Our results show that the density of

  5. Structure of viruses: a short history.

    PubMed

    Rossmann, Michael G

    2013-05-01

    This review is a partially personal account of the discovery of virus structure and its implication for virus function. Although I have endeavored to cover all aspects of structural virology and to acknowledge relevant individuals, I know that I have favored taking examples from my own experience in telling this story. I am anxious to apologize to all those who I might have unintentionally offended by omitting their work. The first knowledge of virus structure was a result of Stanley's studies of tobacco mosaic virus (TMV) and the subsequent X-ray fiber diffraction analysis by Bernal and Fankuchen in the 1930s. At about the same time it became apparent that crystals of small RNA plant and animal viruses could diffract X-rays, demonstrating that viruses must have distinct and unique structures. More advances were made in the 1950s with the realization by Watson and Crick that viruses might have icosahedral symmetry. With the improvement of experimental and computational techniques in the 1970s, it became possible to determine the three-dimensional, near-atomic resolution structures of some small icosahedral plant and animal RNA viruses. It was a great surprise that the protecting capsids of the first virus structures to be determined had the same architecture. The capsid proteins of these viruses all had a 'jelly-roll' fold and, furthermore, the organization of the capsid protein in the virus were similar, suggesting a common ancestral virus from which many of today's viruses have evolved. By this time a more detailed structure of TMV had also been established, but both the architecture and capsid protein fold were quite different to that of the icosahedral viruses. The small icosahedral RNA virus structures were also informative of how and where cellular receptors, anti-viral compounds, and neutralizing antibodies bound to these viruses. However, larger lipid membrane enveloped viruses did not form sufficiently ordered crystals to obtain good X-ray diffraction

  6. Recombinant infectious bursal disease virus carrying hepatitis C virus epitopes.

    PubMed

    Upadhyay, Chitra; Ammayappan, Arun; Patel, Deendayal; Kovesdi, Imre; Vakharia, Vikram N

    2011-02-01

    The delivery of foreign epitopes by a replicating nonpathogenic avian infectious bursal disease virus (IBDV) was explored. The aim of the study was to identify regions in the IBDV genome that are amenable to the introduction of a sequence encoding a foreign peptide. By using a cDNA-based reverse genetics system, insertions or substitutions of sequences encoding epitope tags (FLAG, c-Myc, or hepatitis C virus epitopes) were engineered in the open reading frames of a nonstructural protein (VP5) and the capsid protein (VP2). Attempts were also made to generate recombinant IBDV that displayed foreign epitopes in the exposed loops (P(BC) and P(HI)) of the VP2 trimer. We successfully recovered recombinant IBDVs expressing c-Myc and two different virus-neutralizing epitopes of human hepatitis C virus (HCV) envelope glycoprotein E in the VP5 region. Western blot analyses with anti-c-Myc and anti-HCV antibodies provided positive identification of both the c-Myc and HCV epitopes that were fused to the N terminus of VP5. Genetic analysis showed that the recombinants carrying the c-Myc/HCV epitopes maintained the foreign gene sequences and were stable after several passages in Vero and 293T cells. This is the first report describing efficient expression of foreign peptides from a replication-competent IBDV and demonstrates the potential of this virus as a vector. PMID:21106739

  7. Marek's disease virus latency.

    PubMed

    Morgan, R W; Xie, Q; Cantello, J L; Miles, A M; Bernberg, E L; Kent, J; Anderson, A

    2001-01-01

    MDV latency is defined as the persistence of the viral genome in the absence of production of infectious virus except during reactivation. A number of systems for studying MDV latency exist, and most involve the use of lymphoblastoid cells or tumors. It has been difficult to divorce latency and transformation. Understanding the relationship between these two states remains a major challenge for the MDV system. Based on their patterns of expression, the MDV LATs are apt to be important in the balance between latent and lytic infections. The LATs are a complex group of transcripts. The profile of gene expression that characterizes latency differs among all herpesviruses, and MDV is no exception. MDV LATs bear little resemblance to LATs of other alphaherpesviruses or to the LATs of other lymphotropic herpesviruses. LAT splicing patterns are complex and the relationships among various spliced species or between these species and the large 10-kb transcript are unknown. In addition, the existence of any protein gene products of significance is unknown at this time. More work is needed to further investigate the significance and function of these RNAs. Better technology to construct mutants in the MDV system is badly needed, since the analysis of mutants in the chicken is a powerful and unique advantage of the MDV system. PMID:11217424

  8. Usutu virus in Africa.

    PubMed

    Nikolay, Birgit; Diallo, Mawlouth; Boye, Cheikh Saad Bouh; Sall, Amadou Alpha

    2011-11-01

    Usutu virus (USUV) was discovered in South Africa in 1959. Since then, it has been reported in several African countries including Senegal, Central African Republic, Nigeria, Uganda, Burkina Faso, Cote d'Ivoire, and Morocco. In 2001, USUV has been identified for the first time outside of Africa, namely in Europe, where it caused a significant mortality among blackbirds in Vienna, Austria. In 2009, the first two human cases of USUV infection in Europe have been reported in Italy, causing encephalitis in immunocompromised patients. The host range in Africa includes mainly Culex mosquitoes, birds, and also humans with one benign and one severe case. Given its role as a potential human pathogen and the similar appearance compared with other emerging arboviruses, it is essential to investigate the natural history and ecology of USUV in Africa. In this regard, we review the emergence of USUV in Africa, summarizing data about isolations, host range, and potential vectors, which should help to improve our understanding of the factors underlying the circulation of USUV in Europe and Africa. PMID:21767160

  9. West Nile Virus Infection.

    PubMed

    Sejvar, James J

    2016-06-01

    Although long recognized as a human pathogen, West Nile virus (WNV) emerged as a significant public health problem following its introduction and spread across North America. Subsequent years have seen a greater understanding of all aspects of this viral infection. The North American epidemic resulted in a further understanding of the virology, pathogenesis, clinical features, and epidemiology of WNV infection. Approximately 80% of human WNV infections are asymptomatic. Most symptomatic people experience an acute systemic febrile illness; less than 1% of infected people develop neuroinvasive disease, which typically manifests as meningitis, encephalitis, or anterior myelitis resulting in acute flaccid paralysis. Older age is associated with more severe illness and higher mortality; other risk factors for poor outcome have been challenging to identify. In addition to natural infection through mosquito bites, transfusion- and organ transplant-associated infections have occurred. Since there is no definitive treatment for WNV infection, protection from mosquito bites and other preventative measures are critical. WNV has reached an endemic pattern in North America, but the future epidemiologic pattern is uncertain. PMID:27337465

  10. Ebola, the killer virus.

    PubMed

    Ghazanfar, Haider; Orooj, Fizza; Abdullah, Muhammad Ahmed; Ghazanfar, Ali

    2015-01-01

    Ebola virus disease (EVD) has mostly affected economically deprived countries as limited resources adversely affect a country's infrastructure and administration. Probing into the factors that led to the widespread outbreak, setting forth plans to counter EVD cases in developing countries, and devising definitive measures to limit the spread of the disease are essential steps that must be immediately taken. In this review we summarize the pathogenesis of EVD and the factors that led to its spread. We also highlight interventions employed by certain countries that have successfully limited the epidemic, and add a few preventive measures after studying the current data. According to the available data, barriers to prevent and control the disease in affected countries include irresolute and disorganized health systems, substandard sanitary conditions, poor personal hygiene practices, and false beliefs and stigma related to EVD. The public health sector along with the respective chief authorities in developing countries must devise strategies, keeping the available resources in mind, to deal with the outbreak before it occurs. As a first step, communities should be educated on EVD's symptoms, history, mode of transmission, and methods of protection, including the importance of personal hygiene practices, via seminars, newspapers, and other social media. A popular opinion leader (POL) giving this information would further help to remove the misconception about the nature of the disease and indirectly improve the quality of life of affected patients and their families. PMID:25866626

  11. Oncolytic virus therapies.

    PubMed

    Buonaguro, Franco Maria; Tornesello, Maria Lina; Izzo, Francesco; Buonaguro, Luigi

    2012-11-01

    Oncolytic virus (OV) therapy currently represents one of the most promising approaches to cancer treatment for their dual anticancer mechanisms: direct lysis of cancer cells (oncolytic feature) and activation of the immunosystem (cancer vaccine aspect). The latter demonstrates the advantage of a multi-target approach against multiple tumor-associated antigens. Since the 2005 SFDA (the Chinese FDA) approval for the clinical use of Oncorine™, the first human OV-based cancer treatment, more than 200 patents have been filed worldwide and several Phase I/II studies have been conducted. This patent review analyzes patents and clinical studies of the most promising OV products to highlight the pros and cons of this innovative anticancer approach, which is currently being tested in several cancers (i.e., hepatocellular carcinoma, melanoma and glioblastoma) by systemic as well as intratumoral injection. Clinical results, although effective only for a limited period of time, are encouraging. Combined treatments with radio or chemotherapeutic protocols are also in progress. PMID:24236929

  12. Hepatitis B virus morphogenesis

    PubMed Central

    Bruss, Volker

    2007-01-01

    The hepatitis B virus (HBV) particle consists of an envelope containing three related surface proteins and probably lipid and an icosahedral nucleocapsid of approximately 30 nm diameter enclosing the viral DNA genome and DNA polymerase. The capsid is formed in the cytosol of the infected cell during packaging of an RNA pregenome replication complex by multiple copies of a 21-kDa C protein. The capsid gains the ability to bud during synthesis of the viral DNA genome by reverse transcription of the pregenome in the lumen of the particle. The three envelope proteins S, M, and L shape a complex transmembrane fold at the endoplasmic reticulum, and form disulfide-linked homo- and heterodimers. The transmembrane topology of a fraction of the large envelope protein L changes post-translationally, therefore, the N terminal domain of L (preS) finally appears on both sides of the membrane. During budding at an intracellular membrane, a short linear domain in the cytosolic preS region interacts with binding sites on the capsid surface. The virions are subsequently secreted into the blood. In addition, the surface proteins can bud in the absence of capsids and form subviral lipoprotein particles of 20 nm diameter which are also secreted. PMID:17206755

  13. Stochastic analysis of virus transport in aquifers

    USGS Publications Warehouse

    Campbell, Rehmann L.L.; Welty, C.; Harvey, R.W.

    1999-01-01

    A large-scale model of virus transport in aquifers is derived using spectral perturbation analysis. The effects of spatial variability in aquifer hydraulic conductivity and virus transport (attachment, detachment, and inactivation) parameters on large-scale virus transport are evaluated. A stochastic mean model of virus transport is developed by linking a simple system of local-scale free-virus transport and attached-virus conservation equations from the current literature with a random-field representation of aquifer and virus transport properties. The resultant mean equations for free and attached viruses are found to differ considerably from the local-scale equations on which they are based and include effects such as a free-virus effective velocity that is a function of aquifer heterogeneity as well as virus transport parameters. Stochastic mean free-virus breakthrough curves are compared with local model output in order to observe the effects of spatial variability on mean one-dimensional virus transport in three-dimensionally heterogeneous porous media. Significant findings from this theoretical analysis include the following: (1) Stochastic model breakthrough occurs earlier than local model breakthrough, and this effect is most pronounced for the least conductive aquifers studied. (2) A high degree of aquifer heterogeneity can lead to virus breakthrough actually preceding that of a conservative tracer. (3) As the mean hydraulic conductivity is increased, the mean model shows less sensitivity to the variance of the natural-logarithm hydraulic conductivity and mean virus diameter. (4) Incorporation of a heterogeneous colloid filtration term results in higher predicted concentrations than a simple first-order adsorption term for a given mean attachment rate. (5) Incorporation of aquifer heterogeneity leads to a greater range of virus diameters for which significant breakthrough occurs. (6) The mean model is more sensitive to the inactivation rate of viruses

  14. Viruses and viruslike particles of eukaryotic algae.

    PubMed Central

    Van Etten, J L; Lane, L C; Meints, R H

    1991-01-01

    Until recently there was little interest or information on viruses and viruslike particles of eukaryotic algae. However, this situation is changing. In the past decade many large double-stranded DNA-containing viruses that infect two culturable, unicellular, eukaryotic green algae have been discovered. These viruses can be produced in large quantities, assayed by plaque formation, and analyzed by standard bacteriophage techniques. The viruses are structurally similar to animal iridoviruses, their genomes are similar to but larger (greater than 300 kbp) than that of poxviruses, and their infection process resembles that of bacteriophages. Some of the viruses have DNAs with low levels of methylated bases, whereas others have DNAs with high concentrations of 5-methylcytosine and N6-methyladenine. Virus-encoded DNA methyltransferases are associated with the methylation and are accompanied by virus-encoded DNA site-specific (restriction) endonucleases. Some of these enzymes have sequence specificities identical to those of known bacterial enzymes, and others have previously unrecognized specificities. A separate rod-shaped RNA-containing algal virus has structural and nucleotide sequence affinities to higher plant viruses. Quite recently, viruses have been associated with rapid changes in marine algal populations. In the next decade we envision the discovery of new algal viruses, clarification of their role in various ecosystems, discovery of commercially useful genes in these viruses, and exploitation of algal virus genetic elements in plant and algal biotechnology. Images PMID:1779928

  15. Approximation auto-coherente a deux particules, pseudogap et supraconductivite dans le modele de Hubbard attractif

    NASA Astrophysics Data System (ADS)

    Allen, Steve

    2000-10-01

    Dans cette these nous presentons une nouvelle methode non perturbative pour le calcul des proprietes d'un systeme de fermions. Notre methode generalise l'approximation auto-coherente a deux particules proposee par Vilk et Tremblay pour le modele de Hubbard repulsif. Notre methode peut s'appliquer a l'etude du comportement pre-critique lorsque la symetrie du parametre d'ordre est suffisamment elevee. Nous appliquons la methode au probleme du pseudogap dans le modele de Hubbard attractif. Nos resultats montrent un excellent accord avec les donnees Monte Carlo pour de petits systemes. Nous observons que le regime ou apparait le pseudogap dans le poids spectral a une particule est un regime classique renormalise caracterise par une frequence caracteristique des fluctuations supraconductrices inferieure a la temperature. Une autre caracteristique est la faible densite de superfluide de cette phase demontrant que nous ne sommes pas en presence de paires preformees. Les resultats obtenus semblent montrer que la haute symetrie du parametre d'ordre et la bidimensionalite du systeme etudie elargissent le domaine de temperature pour lequel le regime pseudogap est observe. Nous argumentons que ce resultat est transposable aux supraconducteurs a haute temperature critique ou le pseudogap apparait a des' temperatures beaucoup plus grandes que la temperature critique. La forte symetrie dans ces systemes pourraient etre reliee a la theorie SO(5) de Zhang. En annexe, nous demontrons un resultat tout recent qui permettrait d'assurer l'auto-coherence entre les proprietes a une et a deux particules par l'ajout d'une dynamique au vertex irreductible. Cet ajout laisse entrevoir la possibilite d'etendre la methode au cas d'une forte interaction.

  16. LE135, a retinoid acid receptor antagonist, produces pain through direct activation of TRP channels

    PubMed Central

    Yin, Shijin; Luo, Jialie; Qian, Aihua; Yu, Weihua; Hu, Hongzhen

    2014-01-01

    Background and PurposeRetinoids, through their activation of retinoic acid receptors (RARs) and retinoid X receptors, regulate diverse cellular processes, and pharmacological intervention in their actions has been successful in the treatment of skin disorders and cancers. Despite the many beneficial effects, administration of retinoids causes irritating side effects with unknown mechanisms. Here, we demonstrate that LE135 [4-(7,8,9,10-tetrahydro-5,7,7,10,10-pentamethyl-5H-benzo[e]naphtho[2,3-b][1,4]diazepin-13-yl)benzoic acid], a selective antagonist of RARβ, is a potent activator of the capsaicin (TRPV1) and wasabi (TRPA1) receptors, two critical pain-initiating cation channels. Experimental ApproachWe performed to investigate the excitatory effects of LE135 on TRPV1 and TRPA1 channels expressed in HEK293T cells and in dorsal root ganglia neurons with calcium imaging and patch-clamp recordings. We also used site-directed mutagenesis of the channels to determine the structural basis of LE135-induced activation of TRPV1 and TRPA1 channels and behavioural testing to examine if pharmacological inhibition and genetic deletion of the channels affected LE135-evoked pain-related behaviours. Key ResultsLE135 activated both the capsaicin receptor (TRPV1) and the allyl isothiocyanate receptor (TRPA1) heterologously expressed in HEK293T cells and endogenously expressed by sensory nociceptors. Mutations disrupting the capsaicin-binding site attenuated LE135 activation of TRPV1 channels and a single mutation (K170R) eliminated TRPA1 activity evoked by LE135. Intraplantar injection of LE135 evoked pain-related behaviours. Both TRPV1 and TRPA1 channels were involved in LE135-elicited pain-related responses, as shown by pharmacological and genetic ablation studies. Conclusions and ImplicationsThis blocker of retinoid acid signalling also exerted non-genomic effects through activating the pain-initiating TRPV1 and TRPA1 channels. PMID:24308840

  17. Autophagic machinery activated by dengue virus enhances virus replication

    SciTech Connect

    Lee, Y.-R.; Lei, H.-Y.; Liu, M.-T.; Wang, J.-R.; Chen, S.-H.; Jiang-Shieh, Y.-F.; Lin, Y.-S.; Yeh, T.-M.; Liu, C.-C.; Liu, H.-S.

    2008-05-10

    Autophagy is a cellular response against stresses which include the infection of viruses and bacteria. We unravel that Dengue virus-2 (DV2) can trigger autophagic process in various infected cell lines demonstrated by GFP-LC3 dot formation and increased LC3-II formation. Autophagosome formation was also observed under the transmission electron microscope. DV2-induced autophagy further enhances the titers of extracellular and intracellular viruses indicating that autophagy can promote viral replication in the infected cells. Moreover, our data show that ATG5 protein is required to execute DV2-induced autophagy. All together, we are the first to demonstrate that DV can activate autophagic machinery that is favorable for viral replication.

  18. [Bats and Viruses: complex relationships].

    PubMed

    Rodhain, E

    2015-10-01

    With more than 1 200 species, bats and flying foxes (Order Chiroptera) constitute the most important and diverse order of Mammals after Rodents. Many species of bats are insectivorous while others are frugivorous and few of them are hematophagous. Some of these animals fly during the night, others are crepuscular or diurnal. Some fly long distances during seasonal migrations. Many species are colonial cave-dwelling, living in a rather small home range while others are relatively solitary. However, in spite of the importance of bats for terrestrial biotic communities and ecosystem ecology, the diversity in their biology and lifestyles remain poorly known and underappreciated. More than sixty viruses have been detected or isolated in bats; these animals are therefore involved in the natural cycles of many of them. This is the case, for instance, of rabies virus and other Lyssavirus (Family Rhabdoviridae), Nipah and Hendra viruses (Paramyxoviridae), Ebola and Marburg viruses (Filoviridae), SARS-CoV and MERS-CoV (Coronaviridae). For these zoonotic viruses, a number of bat species are considered as important reservoir hosts, efficient disseminators or even directly responsible of the transmission. Some of these bat-borne viruses cause highly pathogenic diseases while others are of potential significance for humans and domestic or wild animals; so, bats are an important risk in human and animal public health. Moreover, some groups of viruses developed through different phylogenetic mechanisms of coevolution between viruses and bats. The fact that most of these viral infections are asymptomatic in bats has been observed since a long time but the mechanisms of the viral persistence are not clearly understood. The various bioecology of the different bat populations allows exchange of virus between migrating and non-migrating conspecific species. For a better understanding of the role of bats in the circulation of these viral zoonoses, epidemiologists must pay attention to

  19. Circulative, “Nonpropagative” Virus Transmission: An orchestra of virus, insect and plant derived instruments

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The many species of plant viruses within the Luteoviridae, Geminiviridae and Nanoviridae are all transmitted by phloem feeding insects in a circulative, nonpropagative manner. The precise route of virus movement through the vector can differ across and within virus families, but these viruses all sh...

  20. Coping with Computer Viruses: General Discussion and Review of Symantec Anti-Virus for the Macintosh.

    ERIC Educational Resources Information Center

    Primich, Tracy

    1992-01-01

    Discusses computer viruses that attack the Macintosh and describes Symantec AntiVirus for Macintosh (SAM), a commercial program designed to detect and eliminate viruses; sample screen displays are included. SAM is recommended for use in library settings as well as two public domain virus protection programs. (four references) (MES)

  1. Strains of Citrus tristeza virus do not exclude superinfection by other strains of the virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Superinfection exclusion or homologous interference, a phenomenon in which a primary viral infection prevents a secondary infection with the same or closely-related virus, has been observed commonly for viruses in various systems, including viruses of bacteria, plants, and animals. With plant viruse...

  2. Generation of virus like particles for epizootic hemorrhagic disease virus.

    PubMed

    Forzan, Mario; Maan, Sushila; Mazzei, Maurizio; Belaganahalli, Manjunatha N; Bonuccelli, Lucia; Calamari, Monica; Carrozza, Maria Luisa; Cappello, Valentina; Di Luca, Mariagrazia; Bandecchi, Patrizia; Mertens, Peter P C; Tolari, Francesco

    2016-08-01

    Epizootic hemorrhagic disease virus (EHDV) is a distinct species within the genus Orbivirus, within the family Reoviridae. The epizootic hemorrhagic disease virus genome comprises ten segments of linear, double stranded (ds) RNA, which are packaged within each virus particle. The EHDV virion has a three layered capsid-structure, generated by four major viral proteins: VP2 and VP5 (outer capsid layer); VP7 (intermediate, core-surface layer) and VP3 (innermost, sub-core layer). Although EHDV infects cattle sporadically, several outbreaks have recently occurred in this species in five Mediterranean countries, indicating a potential threat to the European cattle industry. EHDV is transmitted by biting midges of the genus Culicoides, which can travel long distances through wind-born movements (particularly over water), increasing the potential for viral spread in new areas/countries. Expression systems to generate self-assembled virus like particles (VLPs) by simultaneous expression of the major capsid-proteins, have been established for several viruses (including bluetongue virus). This study has developed expression systems for production of EHDV VLPs, for use as non-infectious antigens in both vaccinology and serology studies, avoiding the risk of genetic reassortment between vaccine and field strains and facilitating large scale antigen production. Genes encoding the four major-capsid proteins of a field strain of EHDV-6, were isolated and cloned into transfer vectors, to generate two recombinant baculoviruses. The expression of these viral genes was assessed in insect cells by monitoring the presence of specific viral mRNAs and by western blotting. Electron microscopy studies confirmed the formation and purification of assembled VLPs. PMID:27473984

  3. Quantitative nanoscale electrostatics of viruses.

    PubMed

    Hernando-Pérez, M; Cartagena-Rivera, A X; Lošdorfer Božič, A; Carrillo, P J P; San Martín, C; Mateu, M G; Raman, A; Podgornik, R; de Pablo, P J

    2015-11-01

    Electrostatics is one of the fundamental driving forces of the interaction between biomolecules in solution. In particular, the recognition events between viruses and host cells are dominated by both specific and non-specific interactions and the electric charge of viral particles determines the electrostatic force component of the latter. Here we probe the charge of individual viruses in liquid milieu by measuring the electrostatic force between a viral particle and the Atomic Force Microscope tip. The force spectroscopy data of co-adsorbed ϕ29 bacteriophage proheads and mature virions, adenovirus and minute virus of mice capsids is utilized for obtaining the corresponding density of charge for each virus. The systematic differences of the density of charge between the viral particles are consistent with the theoretical predictions obtained from X-ray structural data. Our results show that the density of charge is a distinguishing characteristic of each virus, depending crucially on the nature of the viral capsid and the presence/absence of the genetic material. PMID:26228582

  4. Designing herpes viruses as oncolytics

    PubMed Central

    Peters, Cole; Rabkin, Samuel D

    2015-01-01

    Oncolytic herpes simplex virus (oHSV) was one of the first genetically-engineered oncolytic viruses. Because HSV is a natural human pathogen that can cause serious disease, it is incumbent that it can be genetically-engineered or significantly attenuated for safety. Here, we present a detailed explanation of the functions of HSV-1 genes frequently mutated to endow oncolytic activity. These genes are nonessential for growth in tissue culture cells but are important for growth in postmitotic cells, interfering with intrinsic antiviral and innate immune responses or causing pathology, functions dispensable for replication in cancer cells. Understanding the function of these genes leads to informed creation of new oHSVs with better therapeutic efficacy. Virus infection and replication can also be directed to cancer cells through tumor-selective receptor binding and transcriptional- or post-transcriptional miRNA-targeting, respectively. In addition to the direct effects of oHSV on infected cancer cells and tumors, oHSV can be “armed” with transgenes that are: reporters, to track virus replication and spread; cytotoxic, to kill uninfected tumor cells; immune modulatory, to stimulate antitumor immunity; or tumor microenvironment altering, to enhance virus spread or to inhibit tumor growth. In addition to HSV-1, other alphaherpesviruses are also discussed for their oncolytic activity. PMID:26462293

  5. Optical tweezers to study viruses.

    PubMed

    Arias-Gonzalez, J Ricardo

    2013-01-01

    A virus is a complex molecular machine that propagates by channeling its genetic information from cell to cell. Unlike macroscopic engines, it operates in a nanoscopic world under continuous thermal agitation. Viruses have developed efficient passive and active strategies to pack and release nucleic acids. Some aspects of the dynamic behavior of viruses and their substrates can be studied using structural and biochemical techniques. Recently, physical techniques have been applied to dynamic studies of viruses in which their intrinsic mechanical activity can be measured directly. Optical tweezers are a technology that can be used to measure the force, torque and strain produced by molecular motors, as a function of time and at the single-molecule level. Thanks to this technique, some bacteriophages are now known to be powerful nanomachines; they exert force in the piconewton range and their motors work in a highly coordinated fashion for packaging the viral nucleic acid genome. Nucleic acids, whose elasticity and condensation behavior are inherently coupled to the viral packaging mechanisms, are also amenable to examination with optical tweezers. In this chapter, we provide a comprehensive analysis of this laser-based tool, its combination with imaging methods and its application to the study of viruses and viral molecules. PMID:23737055

  6. Droplet Microfluidics for Virus Discovery

    NASA Astrophysics Data System (ADS)

    Rotem, Assaf; Cockrell, Shelley; Guo, Mira; Pipas, James; Weitz, David

    2012-02-01

    The ability to detect, isolate, and characterize an infectious agent is important for diagnosing and curing infectious diseases. Detecting new viral diseases is a challenge because the number of virus particles is often low and/or localized to a small subset of cells. Even if a new virus is detected, it is difficult to isolate it from clinical or environmental samples where multiple viruses are present each with very different properties. Isolation is crucial for whole genome sequencing because reconstructing a genome from fragments of many different genomes is practically impossible. We present a Droplet Microfluidics platform that can detect, isolate and sequence single viral genomes from complex samples containing mixtures of many viruses. We use metagenomic information about the sample of mixed viruses to select a short genomic sequence whose genome we are interested in characterizing. We then encapsulate single virions from the same sample in picoliter volume droplets and screen for successful PCR amplification of the sequence of interest. The selected drops are pooled and their contents sequenced to reconstruct the genome of interest. This method provides a general tool for detecting, isolating and sequencing genetic elements in clinical and environmental samples.

  7. Control of viruses infecting grapevine.

    PubMed

    Maliogka, Varvara I; Martelli, Giovanni P; Fuchs, Marc; Katis, Nikolaos I

    2015-01-01

    Grapevine is a high value vegetatively propagated fruit crop that suffers from numerous viruses, including some that seriously affect the profitability of vineyards. Nowadays, 64 viruses belonging to different genera and families have been reported in grapevines and new virus species will likely be described in the future. Three viral diseases namely leafroll, rugose wood, and infectious degeneration are of major economic importance worldwide. The viruses associated with these diseases are transmitted by mealybugs, scale and soft scale insects, or dagger nematodes. Here, we review control measures of the major grapevine viral diseases. More specifically, emphasis is laid on (i) approaches for the production of clean stocks and propagative material through effective sanitation, robust diagnosis, as well as local and regional certification efforts, (ii) the management of vectors of viruses using cultural, biological, and chemical methods, and (iii) the production of resistant grapevines mainly through the application of genetic engineering. The benefits and limitations of the different control measures are discussed with regard to accomplishments and future research directions. PMID:25591880

  8. Viruses and thyroiditis: an update

    PubMed Central

    Desailloud, Rachel; Hober, Didier

    2009-01-01

    Viral infections are frequently cited as a major environmental factor involved in subacute thyroiditis and autoimmune thyroid diseases This review examines the data related to the role of viruses in the development of thyroiditis. Our research has been focused on human data. We have reviewed virological data for each type of thyroiditis at different levels of evidence; epidemiological data, serological data or research on circulating viruses, direct evidence of thyroid tissue infection. Interpretation of epidemiological and serological data must be cautious as they don't prove that this pathogen is responsible for the disease. However, direct evidence of the presence of viruses or their components in the organ are available for retroviruses (HFV) and mumps in subacute thyroiditis, for retroviruses (HTLV-1, HFV, HIV and SV40) in Graves's disease and for HTLV-1, enterovirus, rubella, mumps virus, HSV, EBV and parvovirus in Hashimoto's thyroiditis. However, it remains to determine whether they are responsible for thyroid diseases or whether they are just innocent bystanders. Further studies are needed to clarify the relationship between viruses and thyroid diseases, in order to develop new strategies for prevention and/or treatment. PMID:19138419

  9. Role of Lipids in Virus Replication

    PubMed Central

    Lorizate, Maier; Kräusslich, Hans-Georg

    2011-01-01

    Viruses intricately interact with and modulate cellular membranes at several stages of their replication, but much less is known about the role of viral lipids compared to proteins and nucleic acids. All animal viruses have to cross membranes for cell entry and exit, which occurs by membrane fusion (in enveloped viruses), by transient local disruption of membrane integrity, or by cell lysis. Furthermore, many viruses interact with cellular membrane compartments during their replication and often induce cytoplasmic membrane structures, in which genome replication and assembly occurs. Recent studies revealed details of membrane interaction, membrane bending, fission, and fusion for a number of viruses and unraveled the lipid composition of raft-dependent and -independent viruses. Alterations of membrane lipid composition can block viral release and entry, and certain lipids act as fusion inhibitors, suggesting a potential as antiviral drugs. Here, we review viral interactions with cellular membranes important for virus entry, cytoplasmic genome replication, and virus egress. PMID:21628428

  10. Many Americans Misinformed about Zika Virus

    MedlinePlus

    ... news/fullstory_158016.html Many Americans Misinformed About Zika Virus Harvard poll shows they don't know how ... when it comes to understanding the risks of Zika virus, a new Harvard poll has found. The mosquito- ...

  11. FAQ: West Nile Virus and Dead Birds

    MedlinePlus

    ... Education Public Service Videos West Nile Virus & Dead Birds Recommend on Facebook Tweet Share Compartir On this ... dead bird sightings to local authorities. How do birds get infected with West Nile virus? West Nile ...

  12. A "virus" disease of chinook salmon

    USGS Publications Warehouse

    Ross, A.J.; Rucker, R.R.

    1960-01-01

    Epizootics among chinook salmon fingerlings at the Coleman National Fish Hatchery have occurred periodically since 1941. A virus or virus-like filterable agent has been demonstrated to be the causative agent of this disease.

  13. Influenza Virus Infection of Marine Mammals.

    PubMed

    Fereidouni, Sasan; Munoz, Olga; Von Dobschuetz, Sophie; De Nardi, Marco

    2016-03-01

    Interspecies transmission may play a key role in the evolution and ecology of influenza A viruses. The importance of marine mammals as hosts or carriers of potential zoonotic pathogens such as highly pathogenic H5 and H7 influenza viruses is not well understood. The fact that influenza viruses are some of the few zoonotic pathogens known to have caused infection in marine mammals, evidence for direct transmission of influenza A virus H7N7 subtype from seals to man, transmission of pandemic H1N1 influenza viruses to seals and also limited evidence for long-term persistence of influenza B viruses in seal populations without significant genetic change, makes monitoring of influenza viruses in marine mammal populations worth being performed. In addition, such monitoring studies could be a great tool to better understand the ecology of influenza viruses in nature. PMID:25231137

  14. Swine Influenza/Variant Influenza Viruses

    MedlinePlus

    ... Humans Key Facts about Human Infections with Variant Viruses Interim Guidance for Clinicians on Human Infections Background, Risk Assessment & Reporting Reported Infections with Variant Influenza Viruses in the United States since 2005 Prevention Treatment ...

  15. Control of virus diseases of berry crops.

    PubMed

    Martin, Robert R; Tzanetakis, Ioannis E

    2015-01-01

    Virus control in berry crops starts with the development of plants free of targeted pathogens, usually viruses, viroids, phytoplasmas, and systemic bacteria, through a combination of testing and therapy. These then become the top-tier plants in certification programs and are the source from which all certified plants are produced, usually after multiple cycles of propagation. In certification schemes, efforts are made to produce plants free of the targeted pathogens to provide plants of high health status to berry growers. This is achieved using a systems approach to manage virus vectors. Once planted in fruit production fields, virus control shifts to disease control where efforts are focused on controlling viruses or virus complexes that result in disease. In fruiting fields, infection with a virus that does not cause disease is of little concern to growers. Virus control is based on the use of resistance and tolerance, vector management, and isolation. PMID:25591882

  16. Avian Influenza A Virus Infections in Humans

    MedlinePlus

    ... Research Making a Candidate Vaccine Virus Related Links Influenza Types Seasonal Avian Swine Variant Pandemic Other Get ... Submit What's this? Submit Button Past Newsletters Avian Influenza A Virus Infections in Humans Language: English Españ ...

  17. About Epstein-Barr Virus (EBV)

    MedlinePlus

    ... Providers Laboratory Testing References & Resources About Epstein-Barr Virus (EBV) Recommend on Facebook Tweet Share Compartir On ... Page Symptoms Transmission Diagnosis Prevention & Treatment Epstein-Barr virus (EBV), also known as human herpesvirus 4, is ...

  18. A Literature Review of Zika Virus.

    PubMed

    Plourde, Anna R; Bloch, Evan M

    2016-07-01

    Zika virus is a mosquitoborne flavivirus that is the focus of an ongoing pandemic and public health emergency. Previously limited to sporadic cases in Africa and Asia, the emergence of Zika virus in Brazil in 2015 heralded rapid spread throughout the Americas. Although most Zika virus infections are characterized by subclinical or mild influenza-like illness, severe manifestations have been described, including Guillain-Barre syndrome in adults and microcephaly in babies born to infected mothers. Neither an effective treatment nor a vaccine is available for Zika virus; therefore, the public health response primarily focuses on preventing infection, particularly in pregnant women. Despite growing knowledge about this virus, questions remain regarding the virus's vectors and reservoirs, pathogenesis, genetic diversity, and potential synergistic effects of co-infection with other circulating viruses. These questions highlight the need for research to optimize surveillance, patient management, and public health intervention in the current Zika virus epidemic. PMID:27070380

  19. Uveitis Associated with Zika Virus Infection.

    PubMed

    Furtado, João M; Espósito, Danillo L; Klein, Taline M; Teixeira-Pinto, Tomás; da Fonseca, Benedito A

    2016-07-28

    An adult patient recovered from acute Zika virus infection, but ocular symptoms subsequently developed. Anterior uveitis was diagnosed, and Zika virus was identified in the aqueous humor. PMID:27332784

  20. Scientists Try to Stop Another Deadly Virus

    MedlinePlus

    ... Try to Stop Another Deadly Virus Junin, an Ebola-like disease in Argentina, has a death rate ... companies that developed a similar treatment against the Ebola virus during the 2014-2015 outbreak. That drug, ...

  1. Historical review: viruses, crystals and geodesic domes.

    PubMed

    Morgan, Gregory J

    2003-02-01

    In the mid 1950s, Francis Crick and James Watson attempted to explain the structure of spherical viruses. They hypothesized that spherical viruses consist of 60 identical equivalently situated subunits. Such an arrangement has icosahedral symmetry. Subsequent biophysical and electron micrographic data suggested that many viruses had >60 subunits. Drawing inspiration from architecture, Donald Caspar and Aaron Klug discovered a solution to the problem - they proposed that spherical viruses were structured like miniature geodesic domes. PMID:12575996

  2. Characteristics of Filoviridae: Marburg and Ebola Viruses

    NASA Astrophysics Data System (ADS)

    Beer, Brigitte; Kurth, Reinhard; Bukreyev, Alexander

    Filoviruses are enveloped, nonsegmented negative-stranded RNA viruses. The two species, Marburg and Ebola virus, are serologically, biochemically, and genetically distinct. Marburg virus was first isolated during an outbreak in Europe in 1967, and Ebola virus emerged in 1976 as the causative agent of two simultaneous outbreaks in southern Sudan and northern Zaire. Although the main route of infection is known to be person-to-person transmission by intimate contact, the natural reservoir for filoviruses still remains a mystery.

  3. Reverse Genetics of Respiratory Syncytial Virus.

    PubMed

    Stobart, Christopher C; Hotard, Anne L; Meng, Jia; Moore, Martin L

    2016-01-01

    Respiratory syncytial virus (RSV) is a negative-strand RNA virus that is associated with severe lower respiratory tract infections in young infants and the elderly. RSV remains a leading cause worldwide of infant mortality, and despite the high clinical and economic burden of the virus there are currently no available vaccines. Here, we describe the methods for recovery of recombinant RSV viruses using a bacterial artificial chromosome and methods related to procurement and expansion of stocks of RSV mutants. PMID:27464692

  4. [Zika virus, an emerging threat].

    PubMed

    Salinas, Sara; Foulongne, Vincent; Loustalot, Fabien; Fournier-Wirth, Chantal; Molès, Jean-Pierre; Briant, Laurence; Nagot, Nicolas; Van de Perre, Philippe; Simonin, Yannick

    2016-04-01

    Zika virus, discovered in 1947, is particularly publicized because of its involvement in a major epidemic that began in 2015 and which epicenter is located in Latin America, mainly in Brazil. In the majority of cases (70-80 %) the infection is asymptomatic, however in some patients, moderate fever, skin rash, conjunctivitis and myalgia may occur. More alarming, neurological complications are reported, in particular cases of microcephaly probably resulting from the infection of women in the first or second trimester of pregnancy. Moreover, Guillain-Barré syndromes have also been identified in patients whose infection was confirmed. The extent of the current outbreak reveals the very primitive state of knowledge about the pathophysiology of this virus. Thus, a global effort is being undertaken in order to quickly characterize the molecular interaction of the virus with human cells, but also to develop specific diagnostic assays and vaccinal approaches. PMID:27137695

  5. Hepatitis Virus Infections in Poultry.

    PubMed

    Yugo, Danielle M; Hauck, Ruediger; Shivaprasad, H L; Meng, Xiang-Jin

    2016-09-01

    Viral hepatitis in poultry is a complex disease syndrome caused by several viruses belonging to different families including avian hepatitis E virus (HEV), duck hepatitis B virus (DHBV), duck hepatitis A virus (DHAV-1, -2, -3), duck hepatitis virus Types 2 and 3, fowl adenoviruses (FAdV), and turkey hepatitis virus (THV). While these hepatitis viruses share the same target organ, the liver, they each possess unique clinical and biological features. In this article, we aim to review the common and unique features of major poultry hepatitis viruses in an effort to identify the knowledge gaps and aid the prevention and control of poultry viral hepatitis. Avian HEV is an Orthohepevirus B in the family Hepeviridae that naturally infects chickens and consists of three distinct genotypes worldwide. Avian HEV is associated with hepatitis-splenomegaly syndrome or big liver and spleen disease in chickens, although the majority of the infected birds are subclinical. Avihepadnaviruses in the family of Hepadnaviridae have been isolated from ducks, snow geese, white storks, grey herons, cranes, and parrots. DHBV evolved with the host as a noncytopathic form without clinical signs and rarely progressed to chronicity. The outcome for DHBV infection varies by the host's ability to elicit an immune response and is dose and age dependent in ducks, thus mimicking the pathogenesis of human hepatitis B virus (HBV) infections and providing an excellent animal model for human HBV. DHAV is a picornavirus that causes a highly contagious virus infection in ducks with up to 100% flock mortality in ducklings under 6 wk of age, while older birds remain unaffected. The high morbidity and mortality has an economic impact on intensive duck production farming. Duck hepatitis virus Types 2 and 3 are astroviruses in the family of Astroviridae with similarity phylogenetically to turkey astroviruses, implicating the potential for cross-species infections between strains. Duck astrovirus (DAstV) causes

  6. [Capping strategies in RNA viruses].

    PubMed

    Bouvet, Mickaël; Ferron, François; Imbert, Isabelle; Gluais, Laure; Selisko, Barbara; Coutard, Bruno; Canard, Bruno; Decroly, Etienne

    2012-04-01

    Most viruses use the mRNA-cap dependent cellular translation machinery to translate their mRNAs into proteins. The addition of a cap structure at the 5' end of mRNA is therefore an essential step for the replication of many virus families. Additionally, the cap protects the viral RNA from degradation by cellular nucleases and prevents viral RNA recognition by innate immunity mechanisms. Viral RNAs acquire their cap structure either by using cellular capping enzymes, by stealing the cap of cellular mRNA in a process named "cap snatching", or using virus-encoded capping enzymes. Many viral enzymes involved in this process have recently been structurally and functionally characterized. These studies have revealed original cap synthesis mechanisms and pave the way towards the development of specific inhibitors bearing antiviral drug potential. PMID:22549871

  7. Synthesis, characterization, phase diagrams and superconducting and normal state magnetic properties of La{sub 2{minus}x}Sr{sub x}CuO{sub 4} (0 {le} x {le} 0.08) and electrochemically oxidized La{sub 2{minus}x}Sr{sub x}CuO{sub 4+{delta}} (0 {le} x {le} 0.33, 0 {le} {delta} {le} 0.12)

    SciTech Connect

    Chou, F.

    1993-08-01

    La{sub 2{minus}x}Sr{sub x}CuO{sub 4} (0 {le} x {le} 0.15) can all be intercalated with oxygen by a novel electrochemical oxidation method. Bulk superconductivity is found with an onset {Tc} {approx} 40 K for the whole range 0.01 {le} x {le} 0.15; for x = 0.25 and 0.33, the electrochemical oxidation did not improve the superconducting properties. The magnetic susceptibility {chi}(T = 50--320 K) data for La{sub 2}CuO{sub 4.11} and La{sub 1.92}Sr{sub 0.08}CuO{sub 4.07} are nearly identical with those of conventionally prepared La{sub 1.85}Sr{sub 0.15}CuO{sub 4}, indicating that the hole doping level (p) in the CuO{sub 2} planes of the three compounds is nearly the same. Combined thermogravimetric analysis and iodometric titration experiments indicate that part of the intercalated oxygen has a formal valence close to {minus}1. The maximum doped-hole concentration in the CuO{sub 2} planes that can be achieved from combined Sr-doping and electrochemical oxygen doping for 0 {le} x {le} 0.15 is p {approx} 0.16 holes/formula unit. Oxygen can also intercalate into single crystal La{sub 2}CuO{sub 4} through a slow electrochemical oxidation process. The required low current and long time for the charging process reflects that the oxygen intercalation for a single crystal is limited by its small specific surface area and long diffusion distance. The anisotropic superconducting, magnetic and transport properties are summarized and compared with those of polycrystalline La{sub 2}CuO{sub 4+{delta}} as well as of YBa{sub 2}Cu{sub 3}O{sub 7{minus}{delta}} and La{sub 2{minus}x}Sr{sub x}CuO{sub 4} single crystals. The single crystal La{sub 2}CuO{sub 4+{delta}} has a maximum {Tc} {approx} 40 K, which is lower than that ({Tc} {approx} 42--45) of the corresponding polycrystalline samples. The magnetic phase diagram of La{sub 2{minus}x}Sr{sub x}CuO{sub 4} in the antiferromagnetic (AF) regime (0 {le} x {le} 0.02) has been derived from {sup 139}La NQR studies from 4 to 250 K.

  8. Neutralizing antibodies to different proteins of African swine fever virus inhibit both virus attachment and internalization.

    PubMed Central

    Gómez-Puertas, P; Rodríguez, F; Oviedo, J M; Ramiro-Ibáñez, F; Ruiz-Gonzalvo, F; Alonso, C; Escribano, J M

    1996-01-01

    African swine fever virus induces in convalescent pigs antibodies that neutralized the virus before and after binding to susceptible cells, inhibiting both virus attachment and internalization. A further analysis of the neutralization mechanisms mediated by the different viral proteins showed that antibodies to proteins p72 and p54 are involved in the inhibition of a first step of the replication cycle related to virus attachment, while antibodies to protein p30 are implicated in the inhibition of virus internalization. PMID:8764090

  9. Ecological dynamics of emerging bat virus spillover.

    PubMed

    Plowright, Raina K; Eby, Peggy; Hudson, Peter J; Smith, Ina L; Westcott, David; Bryden, Wayne L; Middleton, Deborah; Reid, Peter A; McFarlane, Rosemary A; Martin, Gerardo; Tabor, Gary M; Skerratt, Lee F; Anderson, Dale L; Crameri, Gary; Quammen, David; Jordan, David; Freeman, Paul; Wang, Lin-Fa; Epstein, Jonathan H; Marsh, Glenn A; Kung, Nina Y; McCallum, Hamish

    2015-01-01

    Viruses that originate in bats may be the most notorious emerging zoonoses that spill over from wildlife into domestic animals and humans. Understanding how these infections filter through ecological systems to cause disease in humans is of profound importance to public health. Transmission of viruses from bats to humans requires a hierarchy of enabling conditions that connect the distribution of reservoir hosts, viral infection within these hosts, and exposure and susceptibility of recipient hosts. For many emerging bat viruses, spillover also requires viral shedding from bats, and survival of the virus in the environment. Focusing on Hendra virus, but also addressing Nipah virus, Ebola virus, Marburg virus and coronaviruses, we delineate this cross-species spillover dynamic from the within-host processes that drive virus excretion to land-use changes that increase interaction among species. We describe how land-use changes may affect co-occurrence and contact between bats and recipient hosts. Two hypotheses may explain temporal and spatial pulses of virus shedding in bat populations: episodic shedding from persistently infected bats or transient epidemics that occur as virus is transmitted among bat populations. Management of livestock also may affect the probability of exposure and disease. Interventions to decrease the probability of virus spillover can be implemented at multiple levels from targeting the reservoir host to managing recipient host exposure and susceptibility. PMID:25392474

  10. Citrus tristeza virus-host interactions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Citrus tristeza virus (CTV) is a phloem-limited virus whose natural host range is restricted to citrus and related species. Although the virus has killed millions of trees, almost destroying whole industries, and continually limits production in many citrus growing areas, most isolates are mild or s...

  11. Detection and Diagnosis of Plant Viruses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Diseases caused by viruses are a constant and major problem for crop production worldwide. Human interest in plant genetic resources and globalization of human activities has inadvertently contributed to the spread of viruses throughout the world, increasing the frequency of plant virus outbreaks. C...

  12. Virus detection and quantification using electrical parameters

    PubMed Central

    Ahmad, Mahmoud Al; Mustafa, Farah; Ali, Lizna M.; Rizvi, Tahir A.

    2014-01-01

    Here we identify and quantitate two similar viruses, human and feline immunodeficiency viruses (HIV and FIV), suspended in a liquid medium without labeling, using a semiconductor technique. The virus count was estimated by calculating the impurities inside a defined volume by observing the change in electrical parameters. Empirically, the virus count was similar to the absolute value of the ratio of the change of the virus suspension dopant concentration relative to the mock dopant over the change in virus suspension Debye volume relative to mock Debye volume. The virus type was identified by constructing a concentration-mobility relationship which is unique for each kind of virus, allowing for a fast (within minutes) and label-free virus quantification and identification. For validation, the HIV and FIV virus preparations were further quantified by a biochemical technique and the results obtained by both approaches corroborated well. We further demonstrate that the electrical technique could be applied to accurately measure and characterize silica nanoparticles that resemble the virus particles in size. Based on these results, we anticipate our present approach to be a starting point towards establishing the foundation for label-free electrical-based identification and quantification of an unlimited number of viruses and other nano-sized particles. PMID:25355078

  13. The greasy response to virus infections

    PubMed Central

    Tanner, Lukas Bahati; Lee, Benhur

    2013-01-01

    Previews Virus replication requires lipid metabolism, but how lipids mediate virus infection remains obscure. In this issue, Amini-Bavil-Olyaee et al. (2013) reveal that IFITM proteins disturb cholesterol homeostasis to block virus entry. Previously in Cell, Morita and colleagues (2013) showed the antiviral potency of the lipid mediator protectin D1. PMID:23601099

  14. Computer Viruses and Safe Educational Practices.

    ERIC Educational Resources Information Center

    Azarmsa, Reza

    1991-01-01

    This discussion of computer viruses explains how these viruses may be transmitted, describes their effects on data and/or computer application programs, and identifies three groups that propagate them. Ten major viruses are listed and described, and measures to deal with them are discussed. Nineteen antiviral programs are also listed and…

  15. MODEL OF VIRUS TRANSPORT IN UNSATURATED SOIL

    EPA Science Inventory

    As a result of the recently-proposed mandatory ground-water disinfection requirements to inactivate viruses in potable water supplies, there has been increasing interest in virus fate and transport in the subsurface. everal models have been developed to predict the fate of viruse...

  16. The receptor preference of influenza viruses

    PubMed Central

    Meng, Bo; Marriott, Anthony C.; Dimmock, Nigel J.

    2010-01-01

    Please cite this paper as: Meng et al. (2010) The receptor preference of influenza viruses. Influenza and Other Respiratory Viruses 4(3), 147–153. Objectives  The cell surface receptor used by an influenza virus to infect that cell is an N‐acetyl neuraminic acid (NANA) residue terminally linked by an alpha2,3 or alpha2,6 bond to a carbohydrate moiety of a glycoprotein or glycolipid. Our aim was to determine a quick and technically simple method to determine cell receptor usage by whole influenza A virus particles. Methods  We employed surface plasmon resonance to detect the binding of viruses to fetuin, a naturally occurring glycoprotein that has both alpha2,3‐ and alpha2,6‐linked NANA, and free 3′‐sialyllactose or 6′‐sialyllactose to compete virus binding. All virus stocks were produced in embryonated chicken’s eggs. Results  The influenza viruses tested bound preferentially to NANAalpha2,3Gal or to NANAalpha2,6Gal, or showed no preference. Two PR8 viruses had different binding preferences. Binding preferences of viruses correlated well with their known biological properties. Conclusions  Our data suggest that it is not easy to predict receptor usage by influenza viruses. However, direct experimental determination as described here can inform experiments concerned with viral pathogenesis, biology and structure. In principle, the methodology can be used for any virus that binds to a terminal NANA residue. PMID:20409211

  17. CLASSIFICATION AND NOMENCLATURE OF VIRUSES OF CYANOBACTERIA

    EPA Science Inventory

    The Study Group finds it appropriate that viruses which have as their host cyanobacteria (blue-green algae) should be grouped within the well-categorized families of the bacterial viruses. Thus, the term cyanophage is adopted as a synonym for the vernacular name BGA virus (BGAV) ...

  18. Focus on: Hendra virus in Australia.

    PubMed

    Hughes, Kristopher

    2014-11-29

    Cases of Hendra virus infection in horses in Australia have been seen regularly since the virus was first isolated in 1994. Kristopher Hughes, associate professor of equine medicine at Charles Sturt University in Australia, gives an overview of how knowledge of the virus has developed in the past 20 years. PMID:25431383

  19. Blackberry (Rubus spp.)-Virus Diseases

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Many viruses have been found in blackberries in the Pacific Northwest. Blackberry calico virus (a carlavirus) is universally present in older commercial 'Thornless Loganberry' fields. Similar calico diseases occur in field-run 'Marion', 'Chehalem', 'Olallie', and 'Waldo' blackberries. Other virus di...

  20. Ebola Virus Persistence in Semen Ex Vivo

    PubMed Central

    Fischer, Robert J.; Judson, Seth; Miazgowicz, Kerri; Bushmaker, Trent

    2016-01-01

    On March 20, 2015, a case of Ebola virus disease was identified in Liberia that most likely was transmitted through sexual contact. We assessed the efficiency of detecting Ebola virus in semen samples by molecular diagnostics and the stability of Ebola virus in ex vivo semen under simulated tropical conditions. PMID:26811984