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1.
Plant Dis ; 107(7): 2061-2069, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36510429

RESUMEN

Sweet potato virus disease (SPVD) is a global constraint to sweetpotato (Ipomoea batatas) production, especially under intensive cultivation in the humid tropics such as East Africa. The objectives of this study were to develop a precision SPVD phenotyping protocol, to find new SPVD-resistant genotypes, and to standardize the first stages of screening for SPVD resistance. The first part of the protocol was based on enzyme-linked immunosorbent assay results for sweet potato chlorotic stunt virus (SPCSV) and sweet potato virus C (SPVC) with adjustments to a negative control (uninfected clone Tanzania) and was performed on a prebreeding population (VZ08) comprising 455 clones and 27 check clones graft inoculated under screenhouse conditions. The second part included field studies with 52 selected clones for SPCSV resistance from VZ08 and 8 checks. In screenhouse conditions, the resistant and susceptible check clones performed as expected; 63 clones from VZ08 exhibited lower relative absorbance values for SPCSV and SPVC than inoculated check Tanzania. Field experiments confirmed SPVD resistance of several clones selected by relative absorbance values (nine resistant clones in two locations; that is, 17.3% of the screenhouse selection), supporting the reliability of our method for SPVD-resistance selection. Two clones were promising, exhibiting high storage root yields of 28.7 to 34.9 t ha-1 and SPVD resistance, based on the proposed selection procedure. This modified serological analysis for SPVD-resistance phenotyping might lead to more efficient development of resistant varieties by reducing costs and time at early stages, and provide solid data for marker-assisted selection with a quantitative tool for classifying resistance.[Formula: see text] Copyright © 2023 The Author(s). This is an open access article distributed under the CC BY 4.0 International license.


Asunto(s)
Ipomoea batatas , Potyvirus , Virosis , Virosis/clasificación , Ipomoea batatas/virología , Potyvirus/clasificación , Potyvirus/genética , Tanzanía , Resistencia a la Enfermedad
2.
Viruses ; 13(4)2021 04 13.
Artículo en Inglés | MEDLINE | ID: mdl-33924398

RESUMEN

The emergence of the Zika virus (ZIKV) mirrors its evolutionary nature and, thus, its ability to grow in diversity or complexity (i.e., related to genome, host response, environment changes, tropism, and pathogenicity), leading to it recently joining the circle of closed congenital pathogens. The causal relation of ZIKV to microcephaly is still a much-debated issue. The identification of outbreak foci being in certain endemic urban areas characterized by a high-density population emphasizes that mixed infections might spearhead the recent appearance of a wide range of diseases that were initially attributed to ZIKV. Globally, such coinfections may have both positive and negative effects on viral replication, tropism, host response, and the viral genome. In other words, the possibility of coinfection may necessitate revisiting what is considered to be known regarding the pathogenesis and epidemiology of ZIKV diseases. ZIKV viral coinfections are already being reported with other arboviruses (e.g., chikungunya virus (CHIKV) and dengue virus (DENV)) as well as congenital pathogens (e.g., human immunodeficiency virus (HIV) and cytomegalovirus (HCMV)). However, descriptions of human latent viruses and their impacts on ZIKV disease outcomes in hosts are currently lacking. This review proposes to select some interesting human latent viruses (i.e., herpes simplex virus 2 (HSV-2), Epstein-Barr virus (EBV), human herpesvirus 6 (HHV-6), human parvovirus B19 (B19V), and human papillomavirus (HPV)), whose virological features and co-exposition with ZIKV may provide evidence of the syndemism process, shedding some light on the emergence of the ZIKV-induced global congenital syndrome in South America.


Asunto(s)
Coinfección/complicaciones , Coinfección/virología , Microcefalia/etiología , Virosis/complicaciones , Infección por el Virus Zika/etiología , Coevolución Biológica , Reservorios de Enfermedades/virología , Humanos , Microcefalia/virología , América del Sur , Tropismo Viral , Virosis/clasificación , Latencia del Virus , Replicación Viral , Virus Zika/patogenicidad , Infección por el Virus Zika/congénito
4.
Medicina (B Aires) ; 79(Spec 6/1): 552-558, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31864225

RESUMEN

The proportion of adult population has increased globally and the current projections indicate that, by 2050, the group of 60 years and older will represent 21.1%. There are now vaccines exclusively designed for adults and others that are applied in early life but need to be updated later in life. Vaccines for adults are not only based on their respective age group but are also linked to risk factors like occupation, life style, health situation, among others. At the same time, longevity brings with it a weakening of the immune response to vaccines, a process known as immunosenescence representing an increasing challenge to adequately protect this age group. For some time, WHO has been promoting the term "Vaccination through the life course" allowing for an extension of the vaccination vision and taking adults as an integral part into the national vaccination programs and calendars. There are several vaccine preventable diseases affecting adults, but those associated with influenza virus and pneumococcus are the ones that affect the largest age group. Several recommendations include, additionally, others to prevent diphtheria, tetanus, whooping cough, hepatitis A and B, meningococcus, chickenpox, measles, rubella, mumps, herpes zoster, human papilloma virus and others. There are still many challenges to overcome in order to fully include adults, particularly health personnel, and to make vaccines extensively valued as a prevention tool in order to achieve a healthy life.


La proporción de población de adultos se ha incrementado globalmente y las proyecciones muestran que para el año 2050 los mayores de 60 años representarán el 21.1%. Actualmente se dispone de vacunas dirigidas exclusivamente a adultos y otras que se aplican en niños pero que se deben actualizar a lo largo de la vida. Las vacunas en adultos se administran, no solo por el grupo de edad al que pertenecen, sino también por factores como ocupación, estilos de vida o estado de salud. Al mismo tiempo, la longevidad disminuye la respuesta inmune a las vacunas por el fenómeno de inmunosenescencia, lo cual representa un desafío para proteger adecuadamente a este grupo. Desde hace varios años la OMS, ha propiciado la utilización del término "Vacunación en el curso de la vida" lo cual permite extender la visión de la vacunación y considerar al adulto como una parte integral de los planes y calendarios de inmunización. Existen varias enfermedades prevenibles por vacunas en adultos, pero aquellas asociadas al virus de influenza y al neumococo, son las que comprenden el grupo más extenso. Diversas recomendaciones incluyen, además de estas vacunas, otras dirigidas a prevenir difteria, tétanos, tos convulsa, hepatitis A y B, meningococo, varicela, sarampión, rubéola, parotiditis, herpes zóster, virus del papiloma humano y otras enfermedades. Se reconocen muchos desafíos a superar para poder incorporar plenamente al adulto, incluyendo al personal de salud, y lograr que la vacunación sea una herramienta de prevención valorada ampliamente para el desarrollo de una vida saludable.


Asunto(s)
Infecciones Bacterianas/prevención & control , Vacunas Bacterianas/administración & dosificación , Control de Enfermedades Transmisibles , Programas de Inmunización , Vacunas Virales/administración & dosificación , Virosis/prevención & control , Adolescente , Adulto , Infecciones Bacterianas/clasificación , Humanos , Persona de Mediana Edad , Virosis/clasificación , Adulto Joven
7.
Braz. j. pharm. sci ; 49(4): 821-829, Oct.-Dec. 2013. ilus, tab
Artículo en Inglés | LILACS | ID: lil-704114

RESUMEN

Dengue represents an important health problem in Brazil and therefore there is a great need to develop a vaccine or treatment. The neutralization of the dengue virus by a specific antibody can potentially be applied to therapy. The present paper describes, for the first time, the preparation of Immunoglobulin specific for the dengue virus (anti-DENV IgG), collected from screened Brazilian blood-donations. Production was performed using the classic Cohn-Oncley process with minor modifications. The anti-DENV IgG was biochemically and biophysically characterized and fulfilled the requirements defined by the European Pharmacopoeia. The finished product was able to neutralize different virus serotypes (DENV-1, DENV-2, and DENV-3), while a commercial IgG collected from American blood donations was found to have low anti-dengue antibody titers. Overall, this anti-DENV IgG represents an important step in the study of the therapeutic potential and safety of a specific antibody that neutralizes the dengue virus in humans.


A dengue representa um importante problema de saúde no Brasil, portanto, a identificação de vacina ou tratamento eficaz é uma necessidade urgente. A neutralização do vírus da dengue, por anticorpo específico, tem potencial aplicação terapêutica. Descrevemos aqui, pela primeira vez, a preparação de imunoglobulina específica para o vírus da dengue (IgG anti-DENV), produzida a partir do plasma selecionado de doadores brasileiros. A produção foi realizada utilizando o método clássico de Cohn-Oncley com pequenas modificações. A IgG anti-DENV foi bioquimicamente e biofisicamente caracterizada e cumpriu os requisitos definidos pela Farmacopeia Europeia. O produto final foi capaz de neutralizar diferentes sorotipos do vírus (DENV-1, DENV-2 e DENV-3), enquanto que a IgG comercial, produzida a partir do plasma de doadores americanos, apresentou baixos títulos de anticorpos anti-dengue. No geral, esta IgG anti-DENV representa uma importante etapa para o estudo do potencial terapêutico e segurança da neutralização, por anticorpos específicos, do vírus da dengue em humanos.


Asunto(s)
Donantes de Sangre/clasificación , Inmunoglobulinas Intravenosas/clasificación , Dengue , Virosis/clasificación , Neutralización de Efluentes/clasificación , Virus del Dengue/clasificación
8.
Braz. J. Microbiol. ; 43(4): 1641-1645, Oct.-Dec. 2012. tab
Artículo en Inglés | VETINDEX | ID: vti-2112

RESUMEN

The role of rhinovirus asymptomatic infections in the transmission among close contacts subjects is unknown. We tested health care workers, a pair of one child and a family member and immunocompromised patients (n =191). HRV were detected on 22.9% symptomatic and 3.6% asymptomatic cases suggesting lower transmission among contacts.(AU)


Asunto(s)
Humanos , Virosis/clasificación , Enfermedades Transmisibles , Signos y Síntomas/tendencias
9.
J Oral Pathol Med ; 38(8): 613-22, 2009 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19614862

RESUMEN

OBJECTIVE: Conducted a literature review to identify studies that reported on the oral manifestations in human immunodeficiency virus (HIV) infected children in highly active antiretrovial therapy (HAART) era. METHODS: A search electronic data base were used and the terms used were 'oral lesions' and 'oral manifestations'. The studies of prevalence of oral manifestation in children with HIV worldwide, descriptive studies, case reports, studies on the association of oral lesions and levels of immune suppression, use of HAART and transmission of HIV were included. RESULTS: There have been substantial changes in the management of HIV disease, especially in the past decade because of the use of HAART. However, children are still being infected and present some peculiarities when compared with adults. Molecular epidemiology, transmission and therapy of the common opportunistic oral infections of HIV disease need to be better understood as a consequence of improved anti-HIV strategies. Treatment with HAART improves the immune function and decreases mortality, morbidity, and opportunistic infections in HIV-infected persons. CONCLUSION: The frequency and severity of oral disease associated with HIV infection have reduced considerably, although the use of HAART may be associated with an increased appearance of oral lesions associated with human papillomavirus and potentially increase the risk of later oral squamous cell carcinoma.


Asunto(s)
Atención Dental para Niños , Atención Dental para Enfermos Crónicos , Infecciones por VIH/complicaciones , Estado de Salud , Enfermedades de la Boca/complicaciones , Salud Bucal , Adolescente , Terapia Antirretroviral Altamente Activa , Candidiasis/complicaciones , Candidiasis/virología , Niño , Preescolar , Caries Dental/complicaciones , Caries Dental/virología , Infecciones por VIH/tratamiento farmacológico , Humanos , Lactante , Recién Nacido , Enfermedades de la Boca/clasificación , Enfermedades de la Boca/microbiología , Enfermedades de la Boca/virología , Infecciones Oportunistas/clasificación , Infecciones Oportunistas/complicaciones , Infecciones Oportunistas/microbiología , Infecciones Oportunistas/virología , Enfermedades de las Glándulas Salivales/complicaciones , Enfermedades de las Glándulas Salivales/virología , Virosis/clasificación , Virosis/complicaciones
12.
J Pediatr ; 124(5 Pt 2): S13-6, 1994 May.
Artículo en Inglés | MEDLINE | ID: mdl-8169752

RESUMEN

The epidemiology, molecular structure, cell tropism, and pathophysiology of many human disease-causing viruses have been painstakingly and elegantly characterized during the past 50 years. Vaccines and antiviral drugs of varying efficacy were developed and tested. Despite the relegation of smallpox to a freezer chest and the progress in the control of measles and hepatitis B, the viruses that cause respiratory tract infections remain significant causes of illness and death in pediatric populations worldwide. This discussion surveys the virus groups that contain nearly 200 distinct viruses that cause sporadic and epidemic respiratory infections in children. The epidemiology of infection with the influenza A and B, parainfluenza, and respiratory syncytial viruses and adenoviruses and their impact on infants and children and the groups at highest risk for morbid outcomes are discussed.


Asunto(s)
Infecciones del Sistema Respiratorio , Virosis , Enfermedad Aguda , Niño , Humanos , Lactante , Infecciones del Sistema Respiratorio/clasificación , Infecciones del Sistema Respiratorio/epidemiología , Infecciones del Sistema Respiratorio/microbiología , Factores de Riesgo , Virosis/clasificación , Virosis/epidemiología
14.
Bol Med Hosp Infant Mex ; 35(2): 217-22, 1978.
Artículo en Español | MEDLINE | ID: mdl-203294

RESUMEN

Rotaviruses found in the stools of different infants, hospitalized in the Hospital del Niño del DIF, may be grouped into at least two types according to their RNA composition. The viral RNA composition was analyzed by electrophoresis in agarose gels. The different types can be distinguished by the mobility of the second larger of the 11 segments that make up the viral RNA.


Asunto(s)
Heces/microbiología , Gastroenteritis/microbiología , Virus ARN/aislamiento & purificación , Rotavirus/aislamiento & purificación , Enfermedad Aguda , Preescolar , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Rotavirus/clasificación , Virosis/clasificación
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