Academic literature on the topic 'VIH (Virus)'
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Journal articles on the topic "VIH (Virus)"
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Schwartz, Olivier. "VIH-1 : un virus très Vif !" médecine/sciences 20, no. 2 (2004): 139–41. http://dx.doi.org/10.1051/medsci/2004202139.
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Cabrera Dutan, Karen Michelle, Wilson Andrés Cabrera Dutan, Andrea Nicole Ordóñez Ortiz, and Darwin Rolando Pinchao Obando. "Infección por virus de inmunodeficiencia humana." RECIAMUC 5, no. 4 (2021): 118–28. http://dx.doi.org/10.26820/reciamuc/5.(4).noviembre.2021.118-128.
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La epidemia del Virus de Inmunodeficiencia Humana (VIH) no es un fenómeno actual, sino que viene desde hace ya varios años, específicamente desde la década de los 80, cuando se detectaron los primeros casos en seres humanos. Desde entonces se calcula que 79.3 millones de personas contrajeron el virus desde que comenzó la epidemia. El VIH es el virus que causa el Síndrome de Inmunodeficiencia Adquirida (SIDA). Cuando una persona se infecta con VIH, el virus ataca y debilita al sistema inmunitario. A medida que el sistema inmunitario se debilita, la persona está en riesgo de contraer infecciones y cánceres que pueden ser mortales. El tratamiento del VIH implica tomar medicamentos que reducen la cantidad de virus que hay en el cuerpo. Estos medicamentos se llaman terapia antirretroviral (TAR). No hay ninguna cura eficaz para la infección por el VIH, pero con la atención médica adecuada, puede ser controlada. Una persona puede reducir el riesgo de infección limitando su exposición a los factores de riesgo y tomando medidas preventivas como el uso de preservativos masculinos y femeninos, pruebas de detección y asesoramiento en relación con el VIH y las ITS, uso de antirretrovíricos a modo de prevención, reducción de daños en los consumidores de drogas inyectables, eliminación de la transmisión del VIH de la madre al niño, entre otras. El enfoque general del presente trabajo es abordar los aspectos más relevantes de la Infección por Virus de Inmunodeficiencia Humana (VIH). Los resultados se obtuvieron mediante el desarrollo de una investigación de tipo bibliográfica, delimitada a una metodología de revisión, que permite concluir que la infección por VIH continúa siendo un problema de salud pública de primer orden en el mundo, tanto por su magnitud y evolución temporal como por sus consecuencias sanitarias, sociales y económicas. Por ello es tan importante el diagnóstico y tratamiento precoces, que son la estrategia preventiva más eficiente.
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Figueroa-Montes, Luis E. "Una revisión científica, histórica y reflexiva, sobre los 40 años del descubrimiento del virus de inmunodeficiencia humana." Revista Peruana de Investigación en Salud 8, no. 1 (2024): e2041. http://dx.doi.org/10.35839/repis.8.1.2041.
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El VIH (virus de la inmunodeficiencia humana) es un virus que ataca el sistema inmunitario del cuerpo. Si el VIH no se trata puede causar SIDA (síndrome de inmunodeficiencia adquirida). Hasta la actualidad no existe una cura eficaz. Una vez que se contrae el VIH, se lo tiene de por vida. Sin embargo, con la atención médica adecuada, se puede controlar. Las personas con infección por el VIH que reciben el tratamiento eficaz pueden tener una vida larga y saludable. La presente revisión científica, histórica y reflexiva, tiene como objetivo conocer los principales acontecimientos en estos 40 años del descubrimiento del virus de inmunodeficiencia humana. En la primera parte conoceremos algunos de estos hitos de forma detallada, como ¿Quiénes iniciaron los estudios y publicaciones sobre el VIH? ¿Quiénes obtuvieron el premio nobel por descubrir el VIH? impacto mediático, entre otros. En la discusión conocerás detalles del avance en la vacunación y porque hasta la actualidad no tenemos una vacuna eficaz, algunas alternativas de prevención con antiretrovirales en personas con riesgo de infección y los retos que aún persisten a pesar de tantos años. Conocer los principales eventos alrededor del VIH es fundamental para seguir luchando contra este virus.
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Rodríguez Arrieta, Luis Antonio, Gener Mahaht Rada, Luis Antonio Salazar, and Rita Magola Sierra. "Sarcoma de Kaposi y enfermedad de Castleman multicéntrica VHH-8 positivo - VIH Negativo." Acta Médica Colombiana 43, no. 1S (2019): 30–32. http://dx.doi.org/10.36104/amc.2018.1357.
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El sarcoma de Kaposi y la enfermedad de Castleman multicéntrica/virus herpes humano-8 positivo/virus de la inmunodeficiencia humana negativo representan un subgrupo etiológico dentro del espectro clínico de las enfermedades asociadas al virus herpes humano-8 positivo, inicialmente fueron consideradas dos entidades aisladas. El virus tiene un papel protagónico por su tropismo por el tejido linfoide y su potencial oncogénico. La presencia de sarcoma de Kaposi y enfermedad de Castleman multicéntrica/virus herpes humano-8 (VHH-8) positivo/virus de la inmunodeficiencia humana (VIH) negativo sugiere la posibilidad de una deficiencia inmunológica subyacente. Se presenta un caso de una mujer de 67 años de edad con dermatosis en extremidades de curso indolente y aparición posterior de múltiples adenomegalias, esplenomegalia además síntomas sistémicos. Se destaca el abordaje diagnóstico, la coexistencia de dos enfermedades etiológicamente ligadas al virus herpes humano-8, sin asociación de inmunosupresión
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Boza-Cordero, Ricardo. "VIH/sida y epigenética." Acta Médica Costarricense 65, no. 1 (2023): 1–9. http://dx.doi.org/10.51481/amc.v65i1.1247.
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Desde 1981, el virus de la inmunodeficiencia humana ha afectado a más de 75 millones de personas en el mundo. La prevención, el diagnóstico temprano y, ante todo el empleo de la terapia antirretroviral, ha disminuido su morbimortalidad. Sin embargo, su cura y el desarrollo de una vacuna efectiva aún son objetivos no alcanzables a corto plazo. Una de las barreras para obtener su control es la persistencia crónica de los virus o sus subproductos en los denominados reservorios celulares, lo que induce un proceso inflamatorio crónico complejo que se manifiesta clínicamente como enfermedad cardiovascular, diversos tipos de cáncer, envejecimiento precoz, entre otras patologías. Los procesos intrínsecos que llevan a estos trastornos han estado siendo investigados a profundidad en los últimos años y la epigenética, definida como el estudio de las modificaciones que afectan de manera directa la expresión de los genes, pero sin cambios en la secuencia del ácido desoxirribonuncleico, puede ayudar a desentrañar estos retos. En esta revisión se analizan los mecanismos epigenéticos, como la metilación del ácido desoxirribonuncleico, las modificaciones en histonas y el ácido ribonucleico no codificante, como posibles blancos en el diagnóstico y tratamiento de la inflamación crónica y sus consecuencias clínicas asociadas al virus de inmunodeficiencia humana/sida.
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Castañeda-Sabogal, Alex N., and Lorenzo A. Ruiz-Rodríguez. "Espirometría en pacientes infectados con virus de la inmunodeficiencia humana." REVISTA MÉDICA VALLEJIANA/ Vallejian Medical Journal 11, no. 2 (2022): 32–47. http://dx.doi.org/10.18050/revistamedicavallejiana.v11i2.03.
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Objetivo: Determinar si la evaluación espirométrica en pacientes infectados con VIH es diferente que la de aquellos no infectados por VIH. Material y Métodos: Se llevo a cabo un estudio analítico de doble cohorte retrospectivo. La muestra de estudio estuvo constituida por 22 pacientes que cumplieron los criterios de selección divididos en igual proporción en dos grupos: VIH(+) y VIH(–) a los cuales se les realizó una espirometría. Se uso la prueba de regresión lineal con un modelo considerando solo a la edad, sexo y condición VIH como intervinientes considerando una significancia (valor p) < 0,05. El estudio se realizó en el Hospital Víctor Lazarte Echegaray de Trujillo. Resultados: En el grupo VIH(+) se encontró un patrón espirométrico normal en el 36.36% de los participantes y un patrón espirométrico alterado en el 63,64%. En el grupo VIH(-) se encontró un patrón espirométrico normal en el 72,72% y un patrón espirométrico alterado en el 27,27. En la regresión lineal no se encontró significancia estadística al compararlo con la edad, sexo ni condición VIH. Conclusión: Las espirometrías son similares independientemente de la condición VIH, pero esta, se ve afectada por el tamaño muestral.
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Villagra-Carrón, Verónica, Maria Liz Bobadilla, Gladys Beatriz Olmedo, et al. "Distribución de virus de papiloma humano de alto riesgo oncogénico y otras infecciones de transmisión sexual en mujeres paraguayas con y sin virus de la inmunodeficiencia humana." Memorias del Instituto de Investigaciones en Ciencias de la Salud 20, no. 3 (2022): 134–41. http://dx.doi.org/10.18004/mem.iics/1812-9528/2022.020.03.134.
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El virus de papiloma humano de alto riesgo oncogénico (VPH-AR) es causa necesaria pero no suficiente para la ocurrencia de cáncer de cuello uterino (CCU). Mujeres portadoras del virus de inmunodeficiencia humana (VIH) presentan mayor riesgo de desarrollar lesiones precursoras del cáncer de cuello de útero, por ello, el objetivo del presente trabajo prospectivo de corte transversal fue determinar la frecuencia de VPH-AR y otras infecciones de transmisión sexual-ITS (condilomas, sífilis, virus del herpes simple, gonorrea, citomegalovirus, hepatitis B) en 218 mujeres con y sin VIH que acudieron al Programa Nacional de Lucha contra el SIDA (PRONASIDA) desde julio 2017 hasta marzo 2021. Se encontró que 16/54 (29,6%) mujeres VIH-positivas presentaron infección por VPH-AR en comparación a 41/164 (25%) mujeres VIH-negativas (p>0,05). En relación a la edad, mujeres VIH positivas presentaron una frecuencia comparable de infección por VPH-AR (<30 años: 27,3% vs >30 años 30,2%), a diferencia de mujeres VIH negativas donde hubo una disminución significativa de la infección por VPH-AR luego de los 30 años (<30 años: 33,8% vs >30 años 18,8%, p= 0,028). Esto podría explicarse por la inmunosupresión observada en mujeres VIH positivas que podría favorecer infecciones persistentes, sugiriendo que deben ser controladas más cercanamente. Además, se observó mayor frecuencia de otras ITS en mujeres VIH positivas (29,6% vs 15,8%, p=0,026), lo cual sugiere que aparte del monitoreo más cercano, es fundamental fortalecer la educación sobre factores de riesgo para la ITS sobre todo VPH y VIH, así como la realización de prevención primaria por vacunación contra el VPH
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Robles Pallares, N. E., A. P. Morales Ocaranza, and M. Valles Guereca. "Rescatando Oportunidades Perdidas en el Servicio de Urgencias, en Personas Con VIH." Ciencia Latina Revista Científica Multidisciplinar 8, no. 6 (2024): 3205–12. https://doi.org/10.37811/cl_rcm.v8i6.15081.
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El virus de inmunodeficiencia humana fue identificado en el año 1980, secundario a una neumonía difícil, dicha neumonía la presentaban poblaciones con inmunodeficiencia, la cual se creía que estaba restringida a un pequeño grupo de riesgo, en 1984 se identifica el agente causal de este virus y en 1985 ya se contaba con la primer prueba ELISA para su detección, secundaria al estudio de esta enfermedad se demostró su mecanismo de trasmisión a través del contacto sexual, sangre y vía perinatal. Existen dos tipos de virus, en el continente americano predomina el VIH tipo 1 (VIH-1) en el continente africano es autóctono el VIH tipo 2 (VIH-2). Este virus se ha convertido en uno de los virus más estudiados y con ello se ha modificado favorablemente le esperanza de vida para las personas con VIH, secundario a la suma de éxito en el control de la enfermedad se propone que el seguimiento se en primer nivel de atención. La incidencia global de VIH ha disminuido lentamente pese a los grandes avances en las estrategias de prevención en la transmisión del VIH. Las nuevas infecciones se han reducido en un 54% desde el pico máximo en 1996 y un 32% desde 2010. Las infecciones oportunistas se han identificado como infecciones graves o mayormente frecuentes secundario a la inmunosupresión por el HIV. El reconocimiento de las manifestaciones clínicas es fundamental para determinar el diagnóstico del síndrome de inmunodeficiencia adquirida (SIDA), estas manifestaciones clínicas ocurren en promedio de 7 a 10 años posterior a la exposición al virus. La mortalidad en personas con VIH ha mejorado en las últimas décadas esta mejora se relaciona con amplia disponibilidad y a la mejora de la eficacia y la seguridad del TAR, a la optimización del tiempo para conseguir la supresión virológica y la recuperación inmunológica, y al seguimiento específico de comorbilidades en las personas con VIH.
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Du, Xuejie, Xinqiao Zhan, Xueting Gu, Xinyi Liu, and Bizeng Mao. "Evaluation of Virus-Free Chrysanthemum ‘Hangju’ Productivity and Response to Virus Reinfection in the Field: Molecular Insights into Virus–Host Interactions." Plants 13, no. 5 (2024): 732. http://dx.doi.org/10.3390/plants13050732.
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The shoot apical meristem culture has been used widely to produce virus-free plantlets which have the advantages of strong disease resistance, high yield, and prosperous growth potential. However, this virus-free plant will be naturally reinfected in the field. The physiological and metabolic responses in the reinfected plant are still unknown. The flower of chrysanthemum ‘Hangju’ is a traditional medicine which is unique to China. In this study, we found that the virus-free ‘Hangju’ (VFH) was reinfected with chrysanthemum virus B/R in the field. However, the reinfected VFH (RVFH) exhibited an increased yield and medicinal components compared with virus-infected ‘Hangju’ (VIH). Comparative analysis of transcriptomes was performed to explore the molecular response mechanisms of the RVFH to CVB infection. A total of 6223 differentially expressed genes (DEGs) were identified in the RVFH vs. the VIH. KEGG enrichment and physiological analyses indicated that treatment with the virus-free technology significantly mitigated the plants’ lipid and galactose metabolic stress responses in the RVFH. Furthermore, GO enrichment showed that plant viral diseases affected salicylic acid (SA)-related processes in the RVFH. Specifically, we found that phenylalanine ammonia-lyase (PAL) genes played a major role in defense-related SA biosynthesis in ‘Hangju’. These findings provided new insights into the molecular mechanisms underlying plant virus–host interactions and have implications for developing strategies to improve plant resistance against viruses.
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Artières, Philippe. "La France face au sida." L'Histoire N° 492, no. 2 (2022): 72–76. http://dx.doi.org/10.3917/histo.492.0072.
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VIH/Sida Le terme sida (syndrome immunodéficitaire acquis), version francisée du nom anglo-saxon aids , correspond à un stade de la maladie médicalement défini associé à la présence du virus, d’où l’ajout du sigle VIH (virus de l’immuno-déficience humaine acquise).
Dissertations / Theses on the topic "VIH (Virus)"
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Gaston, Fabrice. "Développement d'inhibiteurs d'entrée du virus VIH-1." Phd thesis, Université de Provence - Aix-Marseille I, 2008. http://tel.archives-ouvertes.fr/tel-00417674.
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La première étape du cycle viral du virus de l'immunodéficience humaine se déroule grâce à l'interaction entre les glycoprotéines d'enveloppe gp120/gp41 et les récepteurs CD4 et CCR5/CXCR4. Les différentes fonctions activées par cette étape, incluant l'attachement, la pénétration et la signalisation cellulaire représentent des cibles potentielles pour le développement d'antirétroviraux. Dans ce travail, nous avons développé des approches permettant d'agir sur chacune de ces étapes à l'aide de peptides synthétiques, d'anticorps anti-peptide et d'inhibiteurs des voies de signalisation. Dans la première approche, nous nous sommes intéressé au développement d'analogues peptidiques de la région HRII en évitant les limitations, incluant courte demi-vie et émergence d'isolats de résistance, rencontrées lors de l'utilisation du peptide T-20 (Fuzeon). Nous avons synthétisé un peptide de 34 acides aminés modélisant la région HRII en incluant des acides aminés non naturels de série D uniquement au niveau de certains sites sensibles à la protéolyse ou dans la totalité de la séquence.Les résultats obtenus montrent que les modifications ponctuelles permettent de : i) maintenir la structure en hélice a du peptide, ii) maintenir sa capacité à interagir avec la région HRI, iii) d'augmenter sa demie-vie et iv) de conserver son activité antivirale. Dans la deuxième approche, nous avons testé la capacité des peptides analogues de la région HRII de VIH-1 et de la boucle V3 de SIV à induire la production d'anticorps neutralisants. Cette étude nous a permis d'aboutir à deux conclusions principales : i) les anticorps anti-HRII peuvent interférer avec l'activité antivirale du peptide administré lors du traitement antiviral, ii) contrairement aux anticorps anti-V3 du VIH-1, les anticorps anti-V3 de SIV sont incapables de neutraliser le virus SIV suggérant des fonctions différentes pour cette région chez HIV-1 et SIV. Dans la troisième partie, nous avons montré que l'attachement du virus VIH sur son récepteur s'accompagne de l'activation de la voie PKC dont l'isoforme PKC-d. L'inhibition de cet isoforme bloque totalement la réplication virale. Ce blocage semble s'opérer en interférant avec les étapes post-entrée du virus en inhibant la formation des pseudopodes et des filaments d'actine, structure nécessaire pour l'étape de la transcription inverse.
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AOUIZERAT, JACK. "Chimisme gastrique et infection liee au virus vih : etude prospective de patients infectes par le virus vih." Nice, 1991. http://www.theses.fr/1991NICE6549.
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Gaston, Fabrice. "Développement d’inhibiteurs d’entrée du virus VIH [Virus de l’Immunodéficience Humaine]-1." Aix-Marseille 1, 2008. http://theses.univ-amu.fr.lama.univ-amu.fr/2008AIX11021.pdf.
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La première étape du cycle viral du virus de l’immunodéficience humaine se déroule grâce à l’interaction entre les glycoprotéines d’enveloppe gp120/gp41 et les récepteurs CD4 et CCR5/CXCR4. Les différentes fonctions activées par cette étape, incluant l’attachement, la pénétration et la signalisation cellulaire représentent des cibles potentielles pour le développement d’antirétroviraux. Dans ce travail, nous avons développé des approches permettant d’agir sur chacune de ces étapes à l’aide de peptides synthétiques, d’anticorps anti-peptide et d’inhibiteurs des voies de signalisation. Dans la première approche, nous nous sommes intéressé au développement d’analogues peptidiques de la région HRII en évitant les limitations, incluant courte demi-vie et émergence d’isolats de résistance, rencontrées lors de l’utilisation du peptide T-20 (Fuzeon). Nous avons synthétisé un peptide de 34 acides aminés modélisant la région HRII en incluant des acides aminés non naturels de série D uniquement au niveau de certains sites sensibles à la protéolyse ou dans la totalité de la séquence. Les résultats obtenus montrent que les modifications ponctuelles permettent de : i) maintenir la structure en hélice a du peptide, ii) maintenir sa capacité à interagir avec la région HRI, iii) d’augmenter sa demie-vie et iv) de conserver son activité antivirale. Dans la deuxième approche, nous avons testé la capacité des peptides analogues de la région HRII de VIH-1 et de la boucle V3 de SIV à induire la production d’anticorps neutralisants. Cette étude nous a permis d’aboutir à deux conclusions principales : i) les anticorps anti-HRII peuvent interférer avec l’activité antivirale du peptide administré lors du traitement antiviral, ii) contrairement aux anticorps anti-V3 du VIH-1, les anticorps anti-V3 de SIV sont incapables de neutraliser le virus SIV suggérant des fonctions différentes pour cette région chez HIV-1 et SIV. Dans la troisième partie, nous avons montré que l’attachement du virus VIH sur son récepteur s’accompagne de l’activation de la voie PKC dont l’isoforme PKC-d. L’inhibition de cet isoforme bloque totalement la réplication virale. Ce blocage semble s’opérer en interférant avec les étapes post-entrée du virus en inhibant la formation des pseudopodes et des filaments d’actine, structure nécessaire pour l’étape de la transcription inverse.
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Alfonso-Candela, Géma. "Etude de l'observance thérapeutique chez les patients infectés par le VIH sous traitement antiretroviral au centre Hospitalier de la Basse-Terre." Antilles-Guyane, 2010. http://www.theses.fr/2009AGUY0313.
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Introduction: Nous avons élaboré une étude observationnelle de cohortes, dans laquelle nous évaluons les différents facteurs influençant l'observance chez les patients VIH sous traitement antirétroviral, ainsi que le pourcentage de non-observance et d'échec thérapeutique des patients suivis au Centre Hospitalier de la Basse-Terre, en Guadeloupe. Méthodes: L'enquête a porté sur 138 patients sous traitement antirétroviral depuis au moins 6 mois, qui ont répondu à un questionnaire d'auto-évaluation des facteurs facilitateurs et des barrières à l'observance. Résultats: Le pourcentage de non-observance a été estimé à 29,71 % et l'échec thérapeutique retrouvé était de 45,65%. Différents facteurs démographiques, culturels et sociaux que nous évaluons expliquent cet échec. Conclusion: La compréhension des facteurs associés à l'observance afin de pouvoir l'augmenter est devenue un enjeu majeur de la recherche tout comme la promotion des interventions d'éducation thérapeutique pour faire connaître aux patients leur maladie et leur traitement, non seulement au moment de l'initiation de celui-ci mais aussi pendant toute la durée du traitement<br>Introduction: We prepared a study observational troops, in whom we evaluate the various factors that influence the observance within the framework of the patients HIV and their antiretroviral treatment. As weil as the percentage of nonobservance and therapeutic failure of the patients followed to the Hospital of Basse-Terre, Guadeloupe. Methods: the investigation related to 138 patients under antiretroviral treatment at least for 6 months, which answered a questionnaire of self-evaluation of the factors facilitators and barriers the observance. Results : The percentage of not-observance was estimated at 29,71 % and the found therapeutic failure was 45,65%. Various demographic factors, cultural and social that we evaluate explain this failure. Conclusion: To understand the factors associated with the observance in order to be able to increase it became a major stake of research like promoting the interventions of therapeutic education to make known with the patients their disease and their treatment, not only at the moment of initiation of the treatment but also throughout all treatment
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Escaich, Sonia. "Étude quantitative et qualitative de la réplication du VIH-1 au cours des différents stades de l'infection : applications au pronostic et au suivi de traitement antiviral." Lyon 1, 1992. http://www.theses.fr/1992LYO1T023.
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Appourchaux, Romain. "Caractérisation et conservation des mécanismes antiviraux des protéines IFITMs." Thesis, Lyon, 2017. http://www.theses.fr/2017LYSEN046.
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IFITM1, 2 et 3 sont des protéines transmembranaires qui sont régulées à la hausse après stimulation interféron. Ces protéines sont capables d’inhiber un large spectre de virus. Le mécanisme d’action admis indique que la présence des IFITMs dans la membrane lipidique des cellules cibles diminue l’entrée des virus en bloquant la fusion de la membrane virale avec la membrane cellulaire.J’ai pris part en début de thèse à un travail qui a permis à notre équipe de mettre en évidence une deuxième configuration antivirale des protéines IFITMs contre le VIH-1 (Virus de l’Immunodéficience Humaine). En effet la présence des IFITMs dans les cellules productrices de virus et non seulement dans les cellules cibles permet deux choses: l’incorporation des IFITMs dans les particules virales et la baisse d’infectivité des virus produits. Suite à cette première étude, nous nous sommes posés deux problématiques: 1) comprendre le mécanisme d’inhibition du VIH-1 par les IFITMs et 2) déterminer le niveau de conservation de cette nouvelle configuration. Mon travail de thèse s’est concentré sur la première et l’utilisation d’un panel de mutants d’IFITM3 a permis: de dissocier l’activité anti VIH-1 et l’incorporation virale et d’identifier des domaines protéiques régulant l’habilité d’IFITM3 à interférer avec la production de particules virales infectieuses. J’ai également participé à travail collaboratif mis en place par notre équipe qui nous a permis de montrer que le mécanisme d’inhibition que nous avons mis en évidence pour le VIH-1 était un mécanisme conservé qui permettait de réduire l’infectivité de nombreux autres virus<br>IFITM1, -2 and -3 are transmembrane proteins, upregulated after type I interferon response and have been shown to inhibit a broad spectrum of viruses. The commonly admitted restriction in the field denotes that the presence of IFITM proteins in the lipidic membranes of target cells decreases viral entry by impeding the viral to cell membrane fusion, essential for the liberation of the core viral into the cytoplasm.I took part at the beginning of my thesis to a teamwork that allowed us to discover a new antiviral mechanisms for these proteins, at least for HIV-1. According to this mechanism, the presence of IFITMs in virus producing cells results in the production of viral particles that incorporate IFITMs and display decreased infectivity.Since then, my PhD work has consisted in: 1) understanding the molecular mechanism by which IFITMs inhibit HIV virion particles and 2) determine the conservation of this novel mechanism of inhibition against other viruses.First, I focused on IFITM3 and tested a large panel of mutants to identify the protein domain(s) required for either incorporation into virions and/or for the antiviral activity. This work allowed me to identify unknown domains in IFITM3 important for the antiviral effect of IFITM3 in virus-producing cells. Second, I have participated to a large collaboration initiated by our team to analyze the antiviral effects that IFITMs exerted on several viruses. Our results indicate that the novel mechanism of inhibition by IFITMs that we have described for HIV is conserved among different classes of viruses
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GOMMY, FLORENCE. "Lymphomes et vih." Aix-Marseille 2, 1994. http://www.theses.fr/1994AIX20017.
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Palcidi, Laurent. "Etude pharmacologique des analogues nucléosidiques à activité anti-VIH et anti-VHB." Aix-Marseille 2, 2000. http://www.theses.fr/2000AIX22060.
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Beniguel, Lydie. "Etude et modélisation de la production d'anticorps anti-VIH chez des personnes infectées par le virus de l'immunodéficience humaine de type 1." Saint-Etienne, 2003. http://www.theses.fr/2003STET005T.
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L'infection par le VIH induit de nombreux dysfonctionnements du compartiment lymphocytaire B. Ainsi, les organes lymphoïdes secondaires, sites de développement des réponses immunitaires spécifiques, sont des réservoirs de virus inaccessibles aux traitements antirétroviraux. La persistance du virus induit une stimulation chronique des cellules immunitaires qui aboutie à une hyperactivation cellulaire. Nous nous sommes interessés à la caractérisation des réponses humorales chez des sujets infectés par le VIH, évoluant dans un environnement tropical. Ces patients ont des charges virales élevées, non-contrôlées par des traitements anti-rétroviraux. L'étude des phénotypes des lymphocytes B circulants à mis en évidence la présence de lymphocytes B centrogerminatifs suggérant une destruction ganglionnaire. Les sujets vivants en zone tropicale présentent également une diminution des lymphocytes B naïfs et des lymphocytes B mémoires et une augmentation des lymphocytes B différenciés. Elle serait due à la présence d'infections parasitaires chroniques stimulant la différenciation cellulaire. Cependant, malgré les dysfonctionnements ganglionnaires et les modifications cellulaires, nous avons montré, dans un système de culture de lymphocytes B issus de PBMC, que les patients sont capables de produire spontanément des AC anti-VIH in vitro contre divers Ag du VIH. Les Ac sont produits en présence de cytokines sans restimulation des Ag exogènes. Ces Ac semblent refléter l'hyperactivation in-vivo mais ils démontrent que l'établissement d'une réponse humorale spécifique contre le VIH a lieu même chez des patients présentants des dysfonctionnement centrogerminatifs. De plus, les patients ont conservé la capacité de produire des Ac anti-VIH de divers isotypes en particulier des IgG1, IgG3 et IgA. Ces données sont intéressantes car certains isotypes, comme les IgA et les IgG3, ont des capacités de neutralisation importante. Cependant, les conditions de stimulation nécessaires pour produire ces Ac restent à déterminer. Les réponses humorales anti-VIH semblent fonctionnelles et pourraient être ciblées afin d'obtenir un bénéfice immunitaire dans le cadre d'un vaccin thérapeutique.
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Tagnouokam, Ngoupo Paul Alain. "Fréquence et profil génétique des doubles infections VIH-1/M+O et formes recombinantes VIH-1/MO au Cameroun." Rouen, 2016. http://www.theses.fr/2016ROUENR11.
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Longtemps considérée comme impossible du fait de leur divergence génétique, la recombinaison entre le VIH-11M pandémique et le VIII-1/0* endémique au Cameroun, a été rapportée à quatre reprises entre 1999 et 2010. Pour être générées, ces formes nécessitent au préalable des doubles infections M+0. De part son épidémiologie moléculaire, le Cameroun est caractérisé par la co-circulation de ces deux variants, ce qui peut donc favoriser les doubles infections VIH-1/M+0 et l'émergence des recombinants VIH-11MO. Une précédente étude de notre équipe a permis de détecter de nouvelles doubles infections et six formes recombinantes putatives, associées ou non à des doubles infections ; mais ces résultats présentaient certaines limites, en particulier épidémiologiques et techniques. Notre travail avait donc pour objectif de mieux caractériser ces doubles infections VIH-1/M+0 et recombinants VIH-1/M0 présentes au Cameroun, en estimant leur fréquence et en analysant leur profil génétique. De mars 2013 à juin 2015, 275 patients dépistés VIH-1 positifs au Centre Pasteur du Cameroun ont été inclus sur la base d'un test de sérotypage, permettant la discrimination des sérotypes M, O et M+0. Des analyses moléculaires spécifiques de groupe ont été ensuite réalisées dans les gènes pol et env, pour confirmer les réactivités sérologiques et rechercher des discordances pollenv, en faveur d'une forme recombinante. Devant un résultat évoquant une double infection M+0 et/ou la présence d'un recombinant MO, une forme recombinante putative a été recherchée par amplification d'une région couvrant le gène vpr, considéré comme possible point chaud de recombinaison. Les génomes complets de ces formes putatives ont ensuite été caractérisés, et les liens génétiques avec les recombinants déjà décrits, recherchés par analyses phylogénétiques. Parmi les 275 patients, 199 (72,4%) étaient mono-réactifs M, 47 (17,1%) mono-réactifs O, et 29 (10,5%) doublement réactifs M+0. Des doubles infections ont été confirmées moléculairement chez 4 patients (1,4%) et la présence de recombinants chez 3 patients (1,1%). Le premier recombinant, « isolé », a été identifié au sein d'un couple ; le second était associé à une forme parentale VIH-1/M. La caractérisation des génomes complets a permis de mettre en évidence des points de cassure au niveau du gène vpr et la région LTR pour le premier, et au niveau du gène vpu et la région LTR pour le second. Aucun lien n'a été identifié entre ces recombinants et les autres recombinants actuellement caractérisés. Les sous-types VIE1-1/M et les sous-groupes VIH-1/0 impliqués étant cohérents avec l'épidémiologie moléculaire au Cameroun, à savoir une majorité de VIH-1/M CRF02_AG et de VIII-1/0 sous-groupe H. L'origine géographique de ces sept patients était différente, et correspondait à cinq des régions administratives du Cameroun. Nos résultats ont permis d'identifier sept nouveaux cas de doubles infections VIH-l/M+0 et. /ou de formes recombinantes vill-umo. Bien qu'elles semblent persister à bas bruit, elles sont toutefois retrouvées dans différentes régions du Cameroun démontrant leur potentiel de diffusion. Ce travail a également permis de caractériser deux nouveaux génomes complets mettant en évidence des points de cassure dans vpr, vpu et les LTR. Ces nouvelles formes ne sont pas liées à celles précédemment décrites, soulignant ainsi la circulation de nombreuses URFs et la dynamique importante d'évolution par recombinaison entre les deux groupes. Il apparaît donc nécessaire de poursuivre la surveillance de diffusion des formes recombinantes MO, pour identifier l'éventuelle émergence d'une CRF_MO, pouvant présenter de meilleures propriétés virologiques et phénotypiques<br>Frequency and genetic profile of HIV-1/M+0 dual infections and HIV-1/1V10 recombinant forms circulating in Cameroon Despite the great genetic divergence between the pandemic HIV-1/M and non pandemic HIV-1/0, four HIV-1/MO intergroup recombinants have been reported in 1999 and 2010. In Cameroon, the co-circulation of two groups (M and 0) provides an ideal environment for HIV-1/MO recombination to occur. In a previous work, we reported new dual infections and six HIV-LIMO putative recombinant forms, associated to or not to dual infections. However, this study had some epidemiological and technical limitations. In the present study, we aimed to estimate the frequency and to characterize genetic profiles of HIV-1/M+0 dual infections, as well as HIV-11M0 recombinant forms in Cameroon. From March 2013 to June 2015, 275 HIV infected patients from Centre Pasteur of Cameroon were included in the study, based on serotyping test, enabling to distinguish HIV serotypes M, 0 and M+0. HIV-1/M and HIV-1/0 specific PCR were further performed in the pol and env genes, in order to confirm serological reactivities, and to detect pollenv discordance, characteristic of putative recombinants. In the likelihood of M+0 dual infections and/or presence of MO recombinant, a breakpoint in the vpr gene, considered a hotspot of recombination was investigated. Finally, full length genomes of recombinants were characterized and genetic link with previous recombinants was investigated by phylogenetic analyses. Among the 275 patients, 199 (72. 4%) were HIV-1/M mono-reactive, 47(17. 1%) HIV-1/0 mono-reactive, and 29 (10. 5%) were M+0 dual reactive. HIV-1/M+0 dual infections were identified in 4 patients (1. 4%), and the presence of recombinants forms in 3 patients (1. 1%). The first recombinant form was detected in a husband and his wife, and was not associated to dual infection, and the second recombinant form was associated to a parental HIV-1/M virus. Full length genomes characterization identified recombinant breakpoints in the vpr gene and the LTR region for the first recombinant form, and in the vpu gene and the LTR region for the second form. No link between these recombinants and previous recombinants was found. HIV-1/M subtypes and HIV-1/0 sub-groups were concordant with the present molecular epidemiology of HIV infection in Cameroon, that is, the predominance of CRF02_AG and HIV-1/0 sub-group H. Geographical origins of patients with HIV-1/M+0 dual infections and HIV-1/M0 recombinants showed that they were from five administrative regions of Cameroon. In this study, we described seven new cases of HIV-1/M+0 dual infections and HIV-1/MO recombinants, thus confirming the co-circulation of these forms in Cameroon. Even though their frequency remains low, these forms are found in different geographical regions of Cameroon, pointing out their diffusion potential. We also characterized full length genomes of two new HIV-1/MO recombinants, and identified breakpoints in vpr and vpu genes as well as LTR regions. No link between these recombinants and previous recombinants was found, showing the circulation of multiple URFs, and the great dynamic evolution between HIV-1/M and HIV-1/0. It is therefore, necessary to improve the surveillance of HIV-11M0 recombinant forms in Cameroon, in order to detect potential emergence of a CRF_MO, and to further study their virological and phenotypic properties
Books on the topic "VIH (Virus)"
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Bignand, Thierry. RÉFLEXIONS SUR L'INFECTION À VIRUS VIH - Etre soi. Editions L'Harmattan, 1998.
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-M, Girard P., Katlama Ch, and Pialoux G, eds. Infection VIH/SIDA: Mémento diagnostique. Doin, 2005.
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prisons, Canada Comité d'experts sur le SIDA et les. Le VIH/SIDA en milieu carcéral: Documentation. Service correctionnel du Canada, 1994.
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Levy, Jay A. El VIH y la patogenesis del SIDA. Fondo De Cultura Economica USA, 2008.
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A, Emini Emilio, ed. The Human immunodeficiency virus: Biology, immunology, and therapy. Princeton University Press, 2002.
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Cedillos, Rolando A. La epidemia invisible: Historias del SIDA en El Salvador. Asociación Institución Salesiana, 2003.
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prisons, Canada Comité d'experts sur le SIDA et les. Le VIH/SIDA en milieu carcéral: Rapport final du Comité d'experts sur le SIDA et les prisons. Service correctionnel du Canada, 1994.
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Gerry, Bally, Gilmore Norbert, and Canadian Medical Association, eds. Counselling guidelines for human immunodeficiency virus serologic testing. Canadian Medical Association, 1993.
Find full textBook chapters on the topic "VIH (Virus)"
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Grumet, Rebecca. "Development of Virus Resistant Plants via Genetic Engineering." In Plant Breeding Reviews. John Wiley & Sons, Inc., 2010. http://dx.doi.org/10.1002/9780470650493.ch3.
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Seleši, Dora. "Virus Diffusion Modeling via Fractional Stochastic Differential Equations." In Trends in Mathematics. Springer Nature Switzerland, 2024. http://dx.doi.org/10.1007/978-3-031-57005-6_34.
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Pavelka, Margit, and Jürgen Roth. "Receptor-Mediated Endocytosis Via Clathrin-Coated Vesicles and Virus Endocytosis." In Functional Ultrastructure. Springer Vienna, 2010. http://dx.doi.org/10.1007/978-3-211-99390-3_48.
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Mulkens, P. S. J. Z., and F. P. Schröder. "Virus Isolation Study of the Human Ganglion Geniculi (Nerve VII)." In The Facial Nerve. Springer Berlin Heidelberg, 1994. http://dx.doi.org/10.1007/978-3-642-85090-5_190.
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Chu, Victor C., Lisa J. McElroy, A. Damon Ferguson, Beverley E. Bauman, and Gary R. Whittaker. "Avian Infectious Bronchitis Virus Enters Cells Via the Endocytic Pathway." In Advances in Experimental Medicine and Biology. Springer US, 2006. http://dx.doi.org/10.1007/978-0-387-33012-9_54.
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Zinkernagel, Rolf M. "Immunosuppression by a Noncytolytic Virus Via T Cell Mediated Immunopathology." In Advances in Experimental Medicine and Biology. Springer US, 1995. http://dx.doi.org/10.1007/978-1-4615-1995-9_14.
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Smail, D. A., and A. L. S. Munro. "Infectious Pancreatic Necrosis Virus in Atlantic Salmon: Transmission via the Sexual Products?" In Viruses of Lower Vertebrates. Springer Berlin Heidelberg, 1989. http://dx.doi.org/10.1007/978-3-642-83727-2_27.
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Caquet, René. "VIH (Virus de l'Immunodéficience Humaine)." In 250 examens de laboratoire. Elsevier, 2010. http://dx.doi.org/10.1016/b978-2-294-71033-9.50205-3.
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Caquet, René. "VIH (virus de l'immunodéficience humaine)." In 250 examens de laboratoire. Elsevier, 2010. http://dx.doi.org/10.1016/b978-2-294-71033-9.50206-5.
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"Reconstituer l’histoire du VIH." In Science et développement durable. IRD Éditions, 2019. http://dx.doi.org/10.4000/12278.
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Le sida, la maladie émergente de la fin du xxe siècle, est principalement dû à un virus, le VIH-1, dont il existe 4 variants. Depuis le début de l’épidémie, plus de 80 millions de personnes ont été contaminées dans le monde. Où et comment un tel virus a-t-il pu émerger ?
Conference papers on the topic "VIH (Virus)"
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Tabarov, A. T., O. V. Andreeva, A. F. Gazizulin, et al. "Influenza A Virus Detection via Ag@c-Si SERS and Machine Learning." In 2024 International Conference Laser Optics (ICLO). IEEE, 2024. http://dx.doi.org/10.1109/iclo59702.2024.10624285.
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Saindis, Dimitrios, George Arvanitakis, and Charalampos Kontoes. "A Chained Approach to Predict West Nile Virus Outbreaks in Fine Temporal Granularity via Satellite Data." In IGARSS 2024 - 2024 IEEE International Geoscience and Remote Sensing Symposium. IEEE, 2024. http://dx.doi.org/10.1109/igarss53475.2024.10641623.
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"SECRETOS DE OFICIO DEL DULCERX." In 23° Congreso de la Sociedad Española de Patología Dual (SEPD) 2021. SEPD, 2021. http://dx.doi.org/10.17579/sepd2021o039.
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A partir del incremento de uso de metanfetamina (denominada localmente como “cristal”) por vía fumada, inyectada, esnifada y/o rectal en la Ciudad de México, y cuyos usuarios se autodenominan coloquialmente como “dulceros”, se presenta el reporte de resultados del programa de Reducción de Riesgos y Daños en Clínica Especializada Condesa. En un primer momento se describe el proceso de elaboración de la guía “Secretos de oficio del dulcerx” que tiene por objetivo captar población de hombres que tienen sexo con hombres que mantienen relaciones sexuales bajo el efecto de metanfetamina, ácido gamma-hidroxibutírico (GHB), ketamina, poppers, estimulantes para la erección, entre otras, la cual está sustentada en una postura enfocada en la reducción de riesgos y daños y ha sido distribuída tanto de manera digital como en sitios de encuentro. En un segundo momento se describe el trabajo colaborativo de pares y organizaciones de la sociedad civil en la difusión e implementación de estrategias descritas en la guía adaptadas para la población mexicana encaminadas a la reducción de riesgos y daños ante el uso de sustancias, así como la reducción de la transmisión de Virus de Inmunodeficiencia Humana (VIH), Virus de Hepatitis B (VHB), Virus de Hepatitis C (VHC), Sífilis y otras Infecciones de Transmisión Sexual (ITS). Por último, se describe el funcionamiento del programa de Reducción de Riesgos y Daños en Clínica Especializada Condesa de la Ciudad de México, en el que se contemplan nueve intervenciones diferentes: a) capacitación para el consumo, b) psicoeducación, c) vacunación, d) pruebas de detección y tratamiento para VIH, VHB, VHC, ITS, e) profilaxis pre y post-exposición, f) deshabituación y sustitución de sustancias, g) recolección segura de parafernalia y, h) entrega de kits de reducción de riesgos y daños, i) intervención psicológica.
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"PS-040 - RELEVANCIA DE LA PATOLOGÍA DUAL EN LA INFECCIÓN DEL VHC EN PACIENTES INGRESADOS EN LA UNIDAD DE HOSPITALIZACIÓN BREVE DE PSIQUIATRÍA DE SALAMANCA." In 24 CONGRESO DE LA SOCIEDAD ESPAÑOLA DE PATOLOGÍA DUAL. SEPD, 2022. http://dx.doi.org/10.17579/abstractbooksepd2022.ps040.
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La prevalencia de hepatitis C es claramente superior en pacientes con adicciones y se ha demostrado la relevancia de la presencia de patología dual en unidades de subagudos de Psiquiatría. Existen pocos datos de su prevalencia y relevancia en Unidades de Hospitalización Breve. Se estudia una muestra de 1841 ingresos realizados entre el enero del 2017 y octubre del 2021. Un 40% eran reingresos de pacientes por lo que se incluyen 1096 pacientes distintos (52,1% eran mujeres), edad media de edad 49,62 (DT=16,27). 340 sujetos (31,3%) padecían Trastornos psicóticos, 180 depresivos (17%), 105 Trastornos de Ansiedad (10,1%), 46 Trastornos de la conducta alimentaria (4,4%), 72 T. Personalidad (6,9%), 34 tenían CI bajo (3,3%). Hasta 112 pacientes tenían diagnóstico principal de T. por consumo de sustancias (10.2%). 15 pacientes fueron positivos en el análisis de Sífilis (1,5%), 47 sujetos para Hepatitis B (4,7%), 28 pacientes para Hepatitis C (2,8%) y 15 fueron positivos para VIH (1,5%). Los pacientes con T. por consumo de sustancias se asociaron a la presencia de hepatitis C p-valor=0,054 y VIH p-valor=0,044. La presencia de pacientes con serología positiva para la hepatitis C en Unidades de Hospitalización Breve Psiquiátrica es muy superior a la esperable para población general y parece estar vinculada a pacientes duales. Roncero, C., Buch-Vicente, B., Martín-Sánchez, Á. M., Álvarez-Navares, A. I., Andrés-Olivera, P., Gamonal-Limcaoco, S., Lozano-López, M. T., Aguilar, L., Sánchez-Casado, F., & García-Ullán, L. (2022). Prevalence of hepatitis C virus infection in patients with chronic mental disorders: The relevance of dual disorders. Gastroenterologia y hepatologia, S0210-5705(22)00172-8. Braude, M. R., Phan, T., Dev, A., & Sievert, W. (2021). Determinants of Hepatitis C Virus Prevalence in People With Serious Mental Illness: A Systematic Review and Meta-Analysis. The Journal of clinical psychiatry, 83(1), 21r14079.
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Cordero Monferrer, Celia Yamila. "Intervención comunitaria en la incidencia del embarazo y de las ITS/VIH/SIDA en adolescentes de “Koskuna”, Veracruz, Panamá. 2021-2022." In VI CONGRESO INVESTIGACIÓN, DESARROLLO E INNOVACIÓN DE LA UNIVERSIDAD INTERNACIONAL DE CIENCIA Y TECNOLOGÍA. Universidad Internacional de Ciencia y Tecnología, 2022. http://dx.doi.org/10.47300/978-9962-738-04-6-34.
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El presente estudio tiene como objetivo elaborar y validar una intervención comunitaria intersectorial en la Incidencia del embarazo y de las infecciones de trasmisión sexual (ITS)/Virus de Inmunodeficiencia Humana (VIH)/Síndrome de Inmunodeficiencia Adquirido (SIDA) en adolescentes de la comunidad indígena de “Koskuna”, corregimiento de Veracruz, Panamá. El diseño de investigación será cuasiexperimental, investigación acción, con mediciones antes y después de la intervención. Se van a medir los conocimientos y actitudes de los adolescentes ante sobre sexualidad y reproducción, con el objetivo de analizar si las diferentes acciones de promoción de salud y medidas preventivas de una intervención comunitaria funcionan para mejorar las prácticas sexuales y lograr un fortalecimiento de una salud sexual y repoductiva responsable, actuando directamente sobre los posibles factores de riesgo que conlleven al aumento de la incidencia del embarazo y las ITS/VIH/SIDA los adolescentes de pueblos originarios. Utilizando un tipo de estudio descriptivo, porque detallara los cambios de los adolescentes durante la intervención, así como explicativo pues nos aportará datos de la eficiencia de la intervención comunitaria intersectorial para la promoción de prácticas sexuales sanas en los adolescentes, incentivando en ellos una sexualidad responsable, y correlacional, porque se analizarán cuáles son los factores de riesgo e infecciones más frecuentes.
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Taborda Vanegas, Natalia A., Gustavo Andrés Castro, Juan C. Hernández López, and María T. Rúgeles López. "Evaluación de marcadores moleculares de inflamación y riesgo cardiovascular en pacientes con el virus de la inmunodeficiencia humana (VIH-1), controladores y progresores." In III Simposio de Investigación Uniremington 2017. Fondo Editorial Remington, 2018. http://dx.doi.org/10.22209/msiu.n3a30.
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"TL 692 ¿ES UN BROTE EPIDÉMICO LA HEPATITIS AGUDA POR VIRUS C EN PERSONAS QUE VIVEN CON VIH (PLHIV)?: REPORTE DE UN CENTRO DE REFERENCIA." In XLIX Congreso Chileno de Gastroenterología. Editorial Iku Limitada, 2022. http://dx.doi.org/10.46613/congastro2022-13.
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Garcia-Guix, Alexandra, Lina Oviedo, Rosa Sauras-Quetcuti, et al. "Modelo de microeliminación de la Hepatitis C. Cascada de cuidados para la hepatitis C del CAS Santa Coloma - Barcelona." In 22° Congreso de la Sociedad Española de Patología Dual (SEPD) 2020. SEPD, 2020. http://dx.doi.org/10.17579/sepd2020o024.
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Objetivo: La transmisión del virus hepatitis C (VHC) en nuestro país es más frecuente en personas que se inyectan drogas y en hombres que tienen sexo con hombres (HSH). Además el policonsumo y la patología dual (PD), implican mayor riesgo de contagio. Los antivirales de acción directa (AAD) han revolucionado el tratamiento del VHC, y suponen una oportunidad para eliminar el virus. El objetivo es describir la implementación del circuito para facilitar el acceso al tratamiento del VHC en el CAS Santa Coloma (desde el diagnóstico en un único paso, el enlace con atención especializada, hasta finalización del tratamiento). Material y métodos: Estudio descriptivo de la trayectoria de los pacientes con VHC admitidos en el centro entre diciembre de 2016 y enero de 2020. Datos recogidos de la revisión de las historias clínicas. Resultados: Del total de pacientes, 122 (20%) presentaban anticuerpos anti-VHC (85 % hombres). En 39 (32%) la viremia fue positiva. De estos, 34 (87, 2%) consumían opiáceos como droga principal y 5 (12, 8 %) otras sustancias. Del total, 39 (32%) presentaban coinfección con VIH. Se detectó presencia de patología dual en 49 (40%) pacientes. La valoración médica fue realizada por Medicina Interna en 24 (61,5%) y por Digestología en 22 (54%). A final de enero/2020, 23 de los pacientes con viremia positiva (60 %) habían iniciado tratamiento con AAD. De ellos 12 (30%) habían conseguido remisión viral sostenida (RVS), 11 (28%) estaban realizando el tratamiento y 16 (41%) estaban pendientes de completar diagnóstico e iniciar tratamiento. Conclusiones: Un 60 % de los pacientes con viremia positiva han iniciado tratamiento con AAD y la totalidad de los que lo han finalizado presenta una RVS. Es necesario simplificar la trayectoria desde la detección hasta el inicio del tratamiento para conseguir la eliminación del VHC en usuarios de drogas.
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Taborda Vanegas, Natalia A., Wbeimar Aguilar, Jorge A. Luján Tangarife, Juan C. Hernández López, and María T. Rúgeles López. "Impacto de la microbiota intestinal en la activación y regulación inmune en sangre periférica de individuos infectados por el virus de la inmunodeficiencia humana (VIH-1)." In III Simposio de Investigación Uniremington 2017. Fondo Editorial Remington, 2018. http://dx.doi.org/10.22209/msiu.n3a32.
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MARTINEZ GARCIA, MIGUEL ANGEL. "Una cuestión de amor. Bios, biopolítica, bioseguridad." In IV Congreso Internacional Estética y Política: Poéticas del desacuerdo para una democracia plural. Editorial Universitat Politècnica de València, 2019. http://dx.doi.org/10.4995/cep4.2019.10261.
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A partir de una experiencia personal (la muerte de un ser querido relacionada con el sida) y de un corpus de producciones artísticas que abordan la experiencia de vivir con VIH (de "vivir con virus", como marca un texto de Marta Dillon), en mi exposición plantearé una pregunta básica: ¿cómo pensamos hoy la vida? ¿Cuál es nuestra relación con lo vivo, con la bios? Esta exposición tendrá la forma de una galería de imágenes, una especie de álbum familiar extendido. El comentario de dichas imágenes (que incluyen los fotogramas de un documental, el registro de distintas piezas artísiticas, algunas fotografías de mi propio álbum familiar o los retratos de Michel Foucault, Luc Montagnier o Donna Haraway) articula y produce el discurso con el que me aproximaré a las respuestas que puede suscitar la pregunta de inicio: ¿cómo entendemos la vida hoy? ¿Qué efectos producen nuestras concepciones de lo vivo? ¿Qué formas de vida resultan o se ajustan a ellas? Más allá de la inercia que nos lleva a considerar al otro como a un extraño, un peligro, un objeto de consumo o un competidor, en mi presentación apuesto por nuestra capacidad para elegir una relación de riesgo, de confianza y de amor hacia las otras. Para ello, en cualquier caso, tendremos que pensar en los dispositivos (biopolíticos, biomédicos, securitarios) que dificultan o inhiben esta elección.
Reports on the topic "VIH (Virus)"
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Hrynick, Tabitha, Godefroid Muzalia, and Myfanwy James. Considérations clés : Communication des risques et engagement communautaire pour la vaccination contre la mpox dans l’est de la République démocratique du Congo. Institute of Development Studies, 2024. http://dx.doi.org/10.19088/sshap.2024.032.
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Cette note stratégique présente des considérations sociales et politiques pour la conception et la mise en œuvre de stratégies de communication des risques et d’engagement communautaire (CREC) liées à la vaccination contre la mpox en République démocratique du Congo (RDC). Une flambée épidémique de mpox (clade I) à l’échelle nationale a été déclarée fin 2022 et touche désormais 23 de ses 26 provinces. En particulier, la flambée épidémique est caractérisée par une transmission interhumaine généralisée, contrairement aux précédentes, qui impliquaient principalement un contact animal-humain. Tandis que des foyers de mpox émergent dans tout le pays, cette note stratégique se concentre sur l’est de la RDC. Cette région est caractérisée par des défis importants, tels que des antécédents politiques complexes et un conflit armé en cours, – ainsi que par un manque d’infrastructures et par l’isolement rural de nombreuses communautés. Ces défis exigent des stratégies conçues et adaptées avec précaution. En outre, une souche du virus de la mpox mutée et plus virulente est également apparue dans la province orientale du Sud-Kivu. Bien que de manière générale, il reste peu de choses à savoir sur la dynamique de transmission de l’épidémie, la transmission par voie sexuelle de la nouvelle souche est préoccupante, et fait courir un risque aux populations stigmatisées telles que les travailleurs du sexe, ainsi qu’à d’autres groupes. Toutefois, dans l’ensemble, les enfants sont la population la plus touchée, la transmission étant associée à un contact physique étroit. Au même titre que les femmes enceintes et les personnes immunodéprimées (p. ex., les personnes atteintes du VIH/SIDA), les enfants sont également exposés à un risque accru de complications et de décès. L’Organisation mondiale de la Santé (OMS) recommande des approches de vaccination ciblées dans le contexte des flambées épidémiques de mpox, y compris en tant que prophylaxie post-exposition pour ces populations. Le ministère de la Santé publique de la RDC a annoncé son intention de vacciner les enfants et les adultes avec les vaccins contre la mpox LC16 et MVA-BN, respectivement, par le biais d’une autorisation d’utilisation d’urgence temporaire, étant donné que ces vaccins ne sont pas encore approuvés dans le pays. Actuellement, les efforts se mobilisent pour concevoir des vaccins et des interventions de CREC connexes. Cette note stratégique s’appuie sur une Table ronde de la SSHAP sur la mpox en RDC (mai 2024), une consultation avec des spécialistes des sciences sociales, des professionnels de la santé et des intervenants de l’aide humanitaire actifs au sein de la région, ou bien informés sur la région et la flambée épidémique, ainsi que sur des publications universitaires et la littérature grise.
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Wang, X. F., and M. Schuldiner. Systems biology approaches to dissect virus-host interactions to develop crops with broad-spectrum virus resistance. United States-Israel Binational Agricultural Research and Development Fund, 2020. http://dx.doi.org/10.32747/2020.8134163.bard.
Full textAbstract:
More than 60% of plant viruses are positive-strand RNA viruses that cause billion-dollar losses annually and pose a major threat to stable agricultural production, including cucumber mosaic virus (CMV) that infects numerous vegetables and ornamental trees. A highly conserved feature among these viruses is that they form viral replication complexes (VRCs) to multiply their genomes by hijacking host proteins and remodeling host intracellular membranes. As a conserved and indispensable process, VRC assembly also represents an excellent target for the development of antiviral strategies that can be used to control a wide-range of viruses. Using CMV and a model virus, brome mosaic virus (BMV), and relying on genomic tools and tailor-made large-scale resources specific for the project, our original objectives were to: 1) Identify host proteins that are required for viral replication complex assembly. 2) Dissect host requirements that determine viral host range. 3) Provide proof-of-concept evidence of a viral control strategy by blocking the viral replication complex-localized phospholipid synthesis. We expect to provide new ways and new concepts to control multiple viruses by targeting a conserved feature among positive-strand RNA viruses based on our results. Our work is going according to the expected timeline and we are progressing well on all aims. For Objective 1, among ~6,000 yeast genes, we have identified 96 hits that were possibly play critical roles in viral replication. These hits are involved in cellular pathways of 1) Phospholipid synthesis; 2) Membrane-shaping; 3) Sterol synthesis and transport; 4) Protein transport; 5) Protein modification, among many others. We are pursuing several genes involved in lipid metabolism and transport because cellular membranes are primarily composed of lipids and lipid compositional changes affect VRC formation and functions. For Objective 2, we have found that CPR5 proteins from monocotyledon plants promoted BMV replication while those from dicotyledon plants inhibited it, providing direct evidence that CPR5 protein determines the host range of BMV. We are currently examining the mechanisms by which dicot CPR5 genes inhibit BMV replication and expressing the dicot CPR5 genes in monocot plants to control BMV infection. For Objective 3, we have demonstrated that substitutions in a host gene involved in lipid synthesis, CHO2, prevented the VRC formation by directing BMV replication protein 1a (BMV 1a), which remodels the nuclear membrane to form VRCs, away from the nuclear membrane, and thus, no VRCs were formed. This has been reported in Journal of Biological Chemistry. Based on the results from Objective 3, we have extended our plan to demonstrate that an amphipathic alpha-helix in BMV 1a is necessary and sufficient to target BMV 1a to the nuclear membrane. We further found that the counterparts of the BMV 1a helix from a group of viruses in the alphavirus-like superfamily, such as CMV, hepatitis E virus, and Rubella virus, are sufficient to target VRCs to the designated membranes, revealing a conserved feature among the superfamily. A joint manuscript describing these exciting results and authored by the two labs will be submitted shortly. We have also successfully set up systems in tomato plants: 1) to efficiently knock down gene expression via virus-induced gene silencing so we could test effects of lacking a host gene(s) on CMV replication; 2) to overexpress any gene transiently from a mild virus (potato virus X) so we could test effects of the overexpressed gene(s) on CMV replication. In summary, we have made promising progress in all three Objectives. We have identified multiple new host proteins that are involved in VRC formation and may serve as good targets to develop antiviral strategies; have confirmed that CPR5 from dicot plants inhibited viral infection and are generating BMV-resistance rice and wheat crops by overexpressing dicot CPR5 genes; have demonstrated to block viral replication by preventing viral replication protein from targeting to the designated organelle membranes for the VRC formation and this concept can be further employed for virus control. We are grateful to BARD funding and are excited to carry on this project in collaboration.
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Gal-On, Amit, Shou-Wei Ding, Victor P. Gaba, and Harry S. Paris. role of RNA-dependent RNA polymerase 1 in plant virus defense. United States Department of Agriculture, 2012. http://dx.doi.org/10.32747/2012.7597919.bard.
Full textAbstract:
Objectives: Our BARD proposal on the impact of RNA-dependent RNA polymerase 1 (RDR1) in plant defense against viruses was divided into four original objectives. 1. To examine whether a high level of dsRNA expression can stimulate RDR1 transcription independent of salicylic acid (SA) concentration. 2. To determine whether the high or low level of RDR1 transcript accumulation observed in virus resistant and susceptible cultivars is associated with viral resistance and susceptibility. 3. To define the biogenesis and function of RDR1-dependent endogenous siRNAs. 4. To understand why Cucumber mosaic virus (CMV) can overcome RDR1-dependent resistance. The objectives were slightly changed due to the unique finding that cucumber has four different RDR1 genes. Background to the topic: RDR1 is a key plant defense against viruses. RDR1 is induced by virus infection and produces viral and plant dsRNAs which are processed by DICERs to siRNAs. siRNAs guide specific viral and plant RNA cleavage or serve as primers for secondary amplification of viral-dsRNA by RDR. The proposal is based on our preliminary results that a. the association of siRNA and RDR1 accumulation with multiple virus resistance, and b. that virus infection induced the RDR1-dependent production of a new class of endogenous siRNAs. However, the precise mechanisms underlying RDR1 induction and siRNA biogenesis due to virus infection remain to be discovered in plants. Major conclusions, solutions and achievements: We found that in the cucurbit family (cucumber, melon, squash, watermelon) there are 3-4 RDR1 genes not documented in other plant families. This important finding required a change in the emphasis of our objectives. We characterized 4 RDR1s in cucumber and 3 in melon. We demonstrated that in cucumber RDR1b is apparently a new broad spectrum virus resistance gene, independent of SA. In melon RDR1b is truncated, and therefore is assumed to be the reason that melon is highly susceptible to many viruses. RDR1c is dramatically induced due to DNA and RNA virus infection, and inhibition of RDR1c expression led to increased virus accumulation which suggested its important on gene silencing/defense mechanism. We show that induction of antiviral RNAi in Arabidopsis is associated with production of a genetically distinct class of virus-activated siRNAs (vasiRNAs) by RNA dependent RNA polymerase-1 targeting hundreds of host genes for RNA silencing by Argonaute-2. Production of vasiRNAs is induced by viruses from two different super groups of RNA virus families, targeted for inhibition by CMV, and correlated with virus resistance independently of viral siRNAs. We propose that antiviral RNAi activate broad-spectrum antiviral activity via widespread silencing of host genes directed by vasiRNAs, in addition to specific antiviral defense Implications both scientific and agricultural: The RDR1b (resistance) gene can now be used as a transcription marker for broad virus resistance. The discovery of vasiRNAs expands the repertoire of siRNAs and suggests that the siRNA-processing activity of Dicer proteins may play a more important role in the regulation of plant and animal gene expression than is currently known. We assume that precise screening of the vasiRNA host targets will lead in the near future for identification of plant genes associate with virus diseases and perhaps other pathogens.
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Bryant, C. A., S. A. Wilks, and C. W. Keevil. Survival of SARS-CoV-2 on the surfaces of food and food packaging materials. Food Standards Agency, 2022. http://dx.doi.org/10.46756/sci.fsa.kww583.
Full textAbstract:
COVID-19, caused by the SARS-CoV-2 virus, was first reported in China in December 2019. The virus has spread rapidly around the world and is currently responsible for 500 million reported cases and over 6.4 million deaths. A risk assessment published by the Foods Standards Agency (FSA) in 2020 (Opens in a new window) concluded that it was very unlikely that you could catch coronavirus via food. This assessment included the worst-case assumption that, if food became contaminated during production, no significant inactivation of virus would occur before consumption. However, the rate of inactivation of virus on products sold at various temperatures was identified as a key uncertainty, because if inactivation does occur more rapidly in some situations, then a lower risk may be more appropriate. This project was commissioned to measure the rate of inactivation of virus on the surface of various types of food and food packaging, reducing that uncertainty. The results will be used to consider whether the assumption currently made in the risk assessment remains appropriate for food kept at a range of temperatures, or whether a lower risk is more appropriate for some. We conducted a laboratory-based study, artificially contaminating infectious SARS-CoV-2 virus onto the surfaces of foods and food packaging. We measured how the amount of infectious virus present on those surfaces declined over time, at a range of temperatures and relative humidity levels, reflecting typical storage conditions. We tested broccoli, peppers, apple, raspberry, cheddar cheese, sliced ham, olives, brine from the olives, white and brown bread crusts, croissants and pain au chocolat. The foods tested were selected as they are commonly sold loose on supermarket shelves or uncovered at deli counters or market stalls, they may be difficult to wash, and they are often consumed without any further processing i.e. cooking. The food packaging materials tested were polyethylene terephthalate (PET1) trays and bottles; aluminium cans and composite drinks cartons. These were selected as they are the most commonly used food packaging materials or consumption of the product may involve direct mouth contact with the packaging. Results showed that virus survival varied depending on the foods and food packaging examined. In several cases, infectious virus was detected for several hours and in some cases for several days, under some conditions tested. For a highly infectious agent such as SARS-CoV-2, which is thought to be transmissible by touching contaminated surfaces and then the face, this confirmation is significant. For most foods tested there was a significant drop in levels of virus contamination over the first 24 hours. However, for cheddar cheese and sliced ham, stored in refrigerated conditions and a range of relative humidity, the virus levels remained high up to a week later, when the testing period was stopped. Both cheddar cheese and sliced ham have high moisture, protein and saturated fat content, possibly offering protection to the virus. When apples and olives were tested, the virus was inactivated to the limit of detection very quickly, within an hour, when the first time point was measured. We suggest that chemicals, such as flavonoids, present in the skin of apples and olives inactivate the virus. The rate of viral decrease was rapid, within a few hours, for croissants and pain au chocolat. These pastries are both coated with a liquid egg wash, which may have an inhibitory effect on the virus. Food packaging materials tested had variable virus survival. For all food packaging, there was a significant drop in levels of virus contamination over the first 24 hours, in all relative humidity conditions and at both 6°C and 21°C; these included PET1 bottles and trays, aluminium cans and composite drinks cartons.
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Tawfik, Aly, Deify Law, Juris Grasis, Joseph Oldham, and Moe Salem. COVID-19 Public Transportation Air Circulation and Virus Mitigation Study. Mineta Transportation Institute, 2022. http://dx.doi.org/10.31979/mti.2021.2036.
Full textAbstract:
COVID-19 may have forever changed our world. Given the limited space and air circulation, potential infections on public transportation could be concerningly high. Accordingly, this study has two objectives: (1) to understand air circulation patterns inside the cabins of buses; and (2) to test the impact of different technologies in mitigating viruses from the air and on surfaces inside bus cabins. For the first objective, different devices, metrics and experiments (including colored smoke; videotaping; anemometers; pressure differentials; particle counts; and 3D numerical simulation models) were utilized and implemented to understand and quantify air circulation inside different buses, with different characteristics, and under different operating conditions (e.g. with windows open and shut). For the second objective, three different live prokaryotic viruses were utilized: Phi6, MS2 and T7. Various technologies (including positive pressure environment inside the cabin, HEPA filters with different MERV ratings, concentrated UV exposure with charged carbon filters in the HVAC systems, center point photocatalytic oxidation technology, ionization, and surface antiviral agents) were tested to evaluate the potential of mitigating COVID-19 infections via air and surfaces in public transportation. The effectiveness of these technologies on the three live viruses was tested in both the lab and in buses in the field. The results of the first objective experiments indicated the efficiency of HVAC system designs, where the speed of air spread was consistently much faster than the speed of air clearing. Hence, indicating the need for additional virus mitigation from the cabin. Results of the second objective experiments indicated that photocatalytic oxidation inserts and UVC lights were the most efficient in mitigating viruses from the air. On the other hand, positive pressure mitigated all viruses from surfaces; however, copper foil tape and fabrics with a high percentage of copper mitigated only the Phi6 virus from surfaces. High-temperature heating was also found to be highly effective in mitigating the different viruses from the vehicle cabin. Finally, limited exploratory experiments to test possible toxic by-products of photocatalytic oxidation and UVC lights inside the bus cabin did not detect any increase in levels of formaldehyde, ozone, or volatile organic compounds. Implementation of these findings in transit buses, in addition to the use of personal protective equipment, could be significantly valuable for protection of passengers and drivers on public transportation modes, possibly against all forms of air-borne viruses.
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Tawfik, Aly, Deify Law, Juris Grasis, Joseph Oldham, and Moe Salem. COVID-19 Public Transportation Air Circulation and Virus Mitigation Study. Mineta Transportation Institute, 2022. http://dx.doi.org/10.31979/mti.2022.2036.
Full textAbstract:
COVID-19 may have forever changed our world. Given the limited space and air circulation, potential infections on public transportation could be concerningly high. Accordingly, this study has two objectives: (1) to understand air circulation patterns inside the cabins of buses; and (2) to test the impact of different technologies in mitigating viruses from the air and on surfaces inside bus cabins. For the first objective, different devices, metrics and experiments (including colored smoke; videotaping; anemometers; pressure differentials; particle counts; and 3D numerical simulation models) were utilized and implemented to understand and quantify air circulation inside different buses, with different characteristics, and under different operating conditions (e.g. with windows open and shut). For the second objective, three different live prokaryotic viruses were utilized: Phi6, MS2 and T7. Various technologies (including positive pressure environment inside the cabin, HEPA filters with different MERV ratings, concentrated UV exposure with charged carbon filters in the HVAC systems, center point photocatalytic oxidation technology, ionization, and surface antiviral agents) were tested to evaluate the potential of mitigating COVID-19 infections via air and surfaces in public transportation. The effectiveness of these technologies on the three live viruses was tested in both the lab and in buses in the field. The results of the first objective experiments indicated the efficiency of HVAC system designs, where the speed of air spread was consistently much faster than the speed of air clearing. Hence, indicating the need for additional virus mitigation from the cabin. Results of the second objective experiments indicated that photocatalytic oxidation inserts and UVC lights were the most efficient in mitigating viruses from the air. On the other hand, positive pressure mitigated all viruses from surfaces; however, copper foil tape and fabrics with a high percentage of copper mitigated only the Phi6 virus from surfaces. High-temperature heating was also found to be highly effective in mitigating the different viruses from the vehicle cabin. Finally, limited exploratory experiments to test possible toxic by-products of photocatalytic oxidation and UVC lights inside the bus cabin did not detect any increase in levels of formaldehyde, ozone, or volatile organic compounds. Implementation of these findings in transit buses, in addition to the use of personal protective equipment, could be significantly valuable for protection of passengers and drivers on public transportation modes, possibly against all forms of air-borne viruses.
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Osburn, Bennie, Marius Ianconescu, Geoffrey Akita, and Rozalia Kaufman. Rapid, Sensitive Bluetongue Virus Serogroup and Serotype Detection Using Polymerase Chain Reaction. United States Department of Agriculture, 1995. http://dx.doi.org/10.32747/1995.7612836.bard.
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The objectives of this proposal were to enhance animal health by 1) development of a BTV serogroup diagnostic assay using polymerase chain reaction (PCR) and 2) development of a BTV serotype specific diagnostic PCR assay. A PCR assay for diagnosis of bluetongue virus (BTV) serogroup from clinical samples meeting the criteria of objective 1 was developed. This PCR assay is more sensitive than virus isolation and has been adopted by both the U.S. and Israeli collaborating laboratories of this project, as well as at least one other U.S. laboratory for routine diagnosis of BTV infection in ruminants. The basic BTV PCR protocol has also become an essential tool in BTV molecular research in both collaborating laboratories. During development of the BTV serotype specific PCR we had the opportunity to investigate a nationwide outbreak of abortions and fatal disease in dogs in the U.S. purportedly due to BTV infection via a BTV contaminated canine vaccine. The BTV serogroup PCR was integral in confirming BTV in tissues from affected dogs and in lots of the suspect vaccine. This led to the first published report of BTV infection in dogs. We discovered that BTV can produce silent persistent infection in canine cell culture. This indicated a need for more stringent screening of biologics for occult BTV infection. A novel mixed cell culture method was developed to identify occult BTV and other occult viral infection cell cultures. Serotype specific primers for PCR detection of all U.S. BTV serotypes and two Israel serotypes (BTV-2 and 10) have been evaluated and are available. A subsequent collaboration would logically include sequencing of the L2 genes of Israel BTV-4, 6 and 16, allowing incorporation of these Israel BTV serotypes into a multiplex PCR assay.
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Epel, Bernard, and Roger Beachy. Mechanisms of intra- and intercellular targeting and movement of tobacco mosaic virus. United States Department of Agriculture, 2005. http://dx.doi.org/10.32747/2005.7695874.bard.
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To cause disease, plant viruses must replicate and spread locally and systemically within the host. Cell-to-cell virus spread is mediated by virus-encoded movement proteins (MPs), which modify the structure and function of plasmodesmata (Pd), trans-wall co-axial membranous tunnels that interconnect the cytoplasm of neighboring cells. Tobacco mosaic virus (TMV) employ a single MP for cell- cell spread and for which CP is not required. The PIs, Beachy (USA) and Epel (Israel) and co-workers, developed new tools and approaches for study of the mechanism of spread of TMV that lead to a partial identification and molecular characterization of the cellular machinery involved in the trafficking process. Original research objectives: Based on our data and those of others, we proposed a working model of plant viral spread. Our model stated that MPᵀᴹⱽ, an integral ER membrane protein with its C-terminus exposed to the cytoplasm (Reichel and Beachy, 1998), alters the Pd SEL, causes the Pd cytoplasmic annulus to dilate (Wolf et al., 1989), allowing ER to glide through Pd and that this gliding is cytoskeleton mediated. The model claimed that in absence of MP, the ER in Pd (the desmotubule) is stationary, i.e. does not move through the Pd. Based on this model we designed a series of experiments to test the following questions: -Does MP potentiate ER movement through the Pd? - In the presence of MP, is there communication between adjacent cells via ER lumen? -Does MP potentiate the movement of cytoskeletal elements cell to cell? -Is MP required for cell-to-cell movement of ER membranes between cells in sink tissue? -Is the binding in situ of MP to RNA specific to vRNA sequences or is it nonspecific as measured in vitro? And if specific: -What sequences of RNA are involved in binding to MP? And finally, what host proteins are associated with MP during intracellular targeting to various subcellular targets and what if any post-translational modifications occur to MP, other than phosphorylation (Kawakami et al., 1999)? Major conclusions, solutions and achievements. A new quantitative tool was developed to measure the "coefficient of conductivity" of Pd to cytoplasmic soluble proteins. Employing this tool, we measured changes in Pd conductivity in epidermal cells of sink and source leaves of wild-type and transgenic Nicotiana benthamiana (N. benthamiana) plants expressing MPᵀᴹⱽ incubated both in dark and light and at 16 and 25 ᵒC (Liarzi and Epel, 2005 (appendix 1). To test our model we measured the effect of the presence of MP on cell-to-cell spread of a cytoplasmic fluorescent probe, of two ER intrinsic membrane protein-probes and two ER lumen protein-probes fused to GFP. The effect of a mutant virus that is incapable of cell-to-cell spread on the spread of these probes was also determined. Our data shows that MP reduces SEL for cytoplasmic molecules, dilates the desmotubule allowing cell-cell diffusion of proteins via the desmotubule lumen and reduces the rate of spread of the ER membrane probes. Replicase was shown to enhance cell-cell spread. The data are not in support of the proposed model and have led us to propose a new model for virus cell-cell spread: this model proposes that MP, an integral ER membrane protein, forms a MP:vRNAER complex and that this ER-membrane complex diffuses in the lipid milieu of the ER into the desmotubule (the ER within the Pd), and spreads cell to cell by simple diffusion in the ER/desmotubule membrane; the driving force for spread is the chemical potential gradient between an infected cell and contingent non-infected neighbors. Our data also suggests that the virus replicase has a function in altering the Pd conductivity. Transgenic plant lines that express the MP gene of the Cg tobamovirus fused to YFP under the control the ecdysone receptor and methoxyfenocide ligand were generated by the Beachy group and the expression pattern and the timing and targeting patterns were determined. A vector expressing this MPs was also developed for use by the Epel lab . The transgenic lines are being used to identify and isolate host genes that are required for cell-to-cell movement of TMV/tobamoviruses. This line is now being grown and to be employed in proteomic studies which will commence November 2005. T-DNA insertion mutagenesis is being developed to identify and isolate host genes required for cell-to-cell movement of TMV.
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Mawassi, Munir, Baozhong Meng, and Lorne Stobbs. Development of Virus Induced Gene Silencing Tools for Functional Genomics in Grapevine. United States Department of Agriculture, 2013. http://dx.doi.org/10.32747/2013.7613887.bard.
Full textAbstract:
Grapevine is perhaps the most widely grown fruit crop. To understand the genetic make-up so as to improve the yield and quality of grapes and grape products, researchers in Europe have recently sequenced the genomes of Pinot noir and its inbred. As expected, function of many grape genes is unknown. Functional genomics studies have become the major focus of grape researchers and breeders. Current genetic approaches for gene function studies include mutagenesis, crossing and genetic transformation. However, these approaches are difficult to apply to grapes and takes long periods of time to accomplish. It is thus imperative to seek new ways for grape functional genomics studies. Virus-induced gene silencing (VIGS) offers an attractive alternative for this purpose and has proven highly effective in several herbaceous plant species including tomato, tobacco and barley. VIGS offers several advantages over existing functional genomics approaches. First, it does not require transformation to silence a plant gene target. Instead, it induces silencing of a plant gene through infection with a virus that contains the target gene sequence, which can be accomplished within a few weeks. Second, different plant genes can be readily inserted into the viral genome via molecular cloning and functions of a large number of genes can be identified within a short period of time. Our long-term goal of this research is to develop VIGS-based tools for grapevine functional genomics, made of the genomes of Grapevine virus A (GVA) from Israel and Grapevine rupestris stem pitting-associated virus (GRSPaV) from Canada. GVA and GRSPaV are members of the Flexiviridae. Both viruses have single-stranded, positive sense RNA genomes, which makes them easy to manipulate genetically and excellent candidates as VIGS vectors. In our three years research, several major breakthroughs have been made by the research groups involved in this project. We have engineered a cDNA clone of GVA into a binary vector that is infectious upon delivery into plantlets of micropropagated Vitis viniferacv. Prime. We further developed the GVA into an expression vector that successfully capable to silence endogenous genes. We also were able to assemble an infectious full-length cDNA clones of GRSPaV. In the following sections Achievements and Detailed description of the research activities, we are presenting the outcome and results of this research in details.
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Mawassi, Munir, and Valerian V. Dolja. Role of the viral AlkB homologs in RNA repair. United States Department of Agriculture, 2014. http://dx.doi.org/10.32747/2014.7594396.bard.
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AlkB proteins that repair DNA via reversing methylation damage are conserved in a broad range of prokaryotes and eukaryotes including plants. Surprisingly, AlkB-domains were discovered in the genomes of numerous plant positive-strand RNA viruses, majority of which belong to the family Flexiviridae. The major goal of this research was to reveal the AlkB functions in the viral infection cycle using a range of complementary genetic and biochemical approaches. Our hypotheses was that AlkB is required for efficient replication and genetic stability of viral RNA genomes The major objectives of the research were to identify the functions of GVA AlkB domain throughout the virus infection cycle in N. benthamiana and grapevine, to investigate possible RNA silencing suppression activity of the viral AlkBs, and to characterize the RNA demethylation activity of the mutated GVA AlkBs in vitro and in vivo to determine methylation status of the viral RNA. Over the duration of project, we have made a very substantial progress with the first two objectives. Because of the extreme low titer of the virus particles in plants infected with the AlkB mutant viruses, we were unable to analyze RNA demethylation activity and therefore had to abandon third objective. The major achievements with our objectives were demonstration of the AlkB function in virus spread and accumulation in both experimental and natural hosts of GVA, discovery of the functional cooperation and physical interaction between AlkB and p10 AlkB in suppression of plant RNA silencing response, developing a powerful virus vector technology for grapevine using GLRaV-2-derived vectors for functional genomics and pathogen control in grapevine, and in addition we used massive parallel sequencing of siRNAs to conduct comparative analysis of the siRNA populations in grape plants infected with AlkB-containing GLRaV-3 versus GLRaV-2 that does not encode AlkB. This analysis revealed dramatically reduced levels of virus-specific siRNAs in plants infected with GLRaV-3 compared to that in GLRaV-2 infection implicating AlkB in suppression of siRNA formation. We are pleased to report that BARD funding resulted in 5 publications directly supported by BARD, one US patent, and 9 more publications also relevant to project. Moreover, two joint manuscripts that summarize work on GVA AlkB (led by Israeli PI) and on viral siRNAs in grapevine (led by US PI in collaboration with University of Basel) are in preparation.