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2.
Plant Physiol ; 187(3): 1221-1234, 2021 11 03.
Artículo en Inglés | MEDLINE | ID: mdl-34618090

RESUMEN

Plant architecture is defined by fates and positions of meristematic tissues and has direct consequences on yield potential and environmental adaptation of the plant. In strawberries (Fragaria vesca L. and F. × ananassa Duch.), shoot apical meristems can remain vegetative or differentiate into a terminal inflorescence meristem. Strawberry axillary buds (AXBs) are located in leaf axils and can either remain dormant or follow one of the two possible developmental fates. AXBs can either develop into stolons needed for clonal reproduction or into branch crowns (BCs) that can bear their own terminal inflorescences under favorable conditions. Although AXB fate has direct consequences on yield potential and vegetative propagation of strawberries, the regulation of AXB fate has so far remained obscure. We subjected a number of woodland strawberry (F. vesca L.) natural accessions and transgenic genotypes to different environmental conditions and growth regulator treatments to demonstrate that strawberry AXB fate is regulated either by environmental or endogenous factors, depending on the AXB position on the plant. We confirm that the F. vesca GIBBERELLIN20-oxidase4 (FvGA20ox4) gene is indispensable for stolon development and under tight environmental regulation. Moreover, our data show that apical dominance inhibits the outgrowth of the youngest AXB as BCs, although the effect of apical dominance can be overrun by the activity of FvGA20ox4. Finally, we demonstrate that the FvGA20ox4 is photoperiodically regulated via FvSOC1 (F. vesca SUPPRESSOR OF OVEREXPRESSION OF CONSTANS1) at 18°C, but at higher temperature of 22°C an unidentified FvSOC1-independent pathway promotes stolon development.


Asunto(s)
Fragaria/fisiología , Interacción Gen-Ambiente , Proteínas de Plantas/metabolismo , Ambiente , Fragaria/anatomía & histología , Fragaria/genética , Fragaria/efectos de la radiación , Meristema/anatomía & histología , Meristema/genética , Meristema/fisiología , Meristema/efectos de la radiación , Fotoperiodo , Proteínas de Plantas/genética
3.
Hum Vaccin Immunother ; 14(9): 2222-2238, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29932850

RESUMEN

In late September 2016, the Americas became the first region in the world to have eliminated endemic transmission of measles virus. Several other countries have also verified measles elimination, and countries in all six World Health Organization regions have adopted measles elimination goals. The public health strategies used to respond to measles outbreaks in elimination settings are thus becoming relevant to more countries. This review highlights the strategies used to limit measles spread in elimination settings: (1) assembly of an outbreak control committee; (2) isolation of measles cases while infectious; (3) exclusion and quarantining of individuals without evidence of immunity; (4) vaccination of susceptible individuals; (5) use of immunoglobulin to prevent measles in exposed susceptible high-risk persons; (6) and maintaining laboratory proficiency for confirmation of measles. Deciding on the extent of containment efforts should be based on the expected benefit of reactive interventions, balanced against the logistical challenges in implementing them.


Asunto(s)
Control de Enfermedades Transmisibles/métodos , Control de Enfermedades Transmisibles/organización & administración , Erradicación de la Enfermedad , Brotes de Enfermedades , Transmisión de Enfermedad Infecciosa/prevención & control , Sarampión/epidemiología , Sarampión/prevención & control , Américas/epidemiología , Humanos
4.
J Exp Bot ; 68(17): 4839-4850, 2017 10 13.
Artículo en Inglés | MEDLINE | ID: mdl-29048562

RESUMEN

According to the external coincidence model, photoperiodic flowering occurs when CONSTANS (CO) mRNA expression coincides with light in the afternoon of long days (LDs), leading to the activation of FLOWERING LOCUS T (FT). CO has evolved in Brassicaceae from other Group Ia CO-like (COL) proteins which do not control photoperiodic flowering in Arabidopsis. COLs in other species have evolved different functions as floral activators or even as repressors. To understand photoperiodic development in the perennial rosaceous model species woodland strawberry, we functionally characterized FvCO, the only Group Ia COL in its genome. We demonstrate that FvCO has a major role in the photoperiodic control of flowering and vegetative reproduction through runners. FvCO is needed to generate a bimodal rhythm of FvFT1 which encodes a floral activator in the LD accession Hawaii-4: a sharp FvCO expression peak at dawn is followed by the FvFT1 morning peak in LDs indicating possible direct regulation, but additional factors that may include FvGI and FvFKF1 are probably needed to schedule the second FvFT1 peak around dusk. These results demonstrate that although FvCO and FvFT1 play major roles in photoperiodic development, the CO-based external coincidence around dusk is not fully applicable to the woodland strawberry.


Asunto(s)
Flores/crecimiento & desarrollo , Fragaria/genética , Hojas de la Planta/crecimiento & desarrollo , Proteínas de Plantas/genética , Flores/genética , Fragaria/crecimiento & desarrollo , Fragaria/metabolismo , Fotoperiodo , Filogenia , Hojas de la Planta/genética , Proteínas de Plantas/metabolismo , Análisis de Secuencia de ADN
5.
Hortic Res ; 4: 17020, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28580150

RESUMEN

Flowering time is an important trait that affects survival, reproduction and yield in both wild and cultivated plants. Therefore, many studies have focused on the identification of flowering time quantitative trait locus (QTLs) in different crops, and molecular control of this trait has been extensively investigated in model species. Here we report the mapping of QTLs for flowering time and vegetative traits in a large woodland strawberry mapping population that was phenotyped both under field conditions and in a greenhouse after flower induction in the field. The greenhouse experiment revealed additive QTLs in three linkage groups (LG), two on both LG4 and LG7, and one on LG6 that explain about half of the flowering time variance in the population. Three of the QTLs were newly identified in this study, and one co-localized with the previously characterized FvTFL1 gene. An additional strong QTL corresponding to previously mapped PFRU was detected in both field and greenhouse experiments indicating that gene(s) in this locus can control the timing of flowering in different environments in addition to the duration of flowering and axillary bud differentiation to runners and branch crowns. Several putative flowering time genes were identified in these QTL regions that await functional validation. Our results indicate that a few major QTLs may control flowering time and axillary bud differentiation in strawberries. We suggest that the identification of causal genes in the diploid strawberry may enable fine tuning of flowering time and vegetative growth in the closely related octoploid cultivated strawberry.

6.
Vaccine ; 31(11): 1523-8, 2013 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-23313652

RESUMEN

INTRODUCTION: In March, 2006, oral rotavirus vaccine was added to Brazil's infant immunization schedule with recommended upper age limits for initiating (by age 14 weeks) and completing (by age 24 weeks) the two-dose series to minimize age-specific risk of intussusception following rotavirus vaccination. Several years after introduction, estimated coverage with rotavirus vaccine (83%) was lower compared to coverage for other recommended childhood immunizations (≥94%). METHODS: We analyzed data from Brazil's national immunization program on uptake of oral rotavirus vaccine by geographic region and compared administrative coverage estimates for first and second doses of oral rotavirus vaccine (Rota1 and Rota2) with first and second doses of diphtheria-tetanus-pertussis-Haemophilus influenzae type b vaccine (DTP-Hib1 and DTP-Hib2). For 27 Brazilian cities, we compared differences between estimated rotavirus and DTP-Hib coverage in 2010 with delayed receipt of DTP-Hib vaccine among a cohort of children surveyed before rotavirus introduction. RESULTS: In 2010, infant vaccination coverage was 99.0% for DTP-Hib1 versus 95.2% for Rota1 (3.8% difference), and 98.4% for DTP-Hib2 versus 83.0% for Rota2 (15.4% difference), with substantial regional variation. Differences between DTP-Hib and rotavirus vaccination coverage in Brazilian cities correlated with delay in DTP-Hib vaccination among children surveyed. Age restrictions for initiating and completing the rotavirus vaccination series likely contributed to lower coverage with rotavirus vaccine in Brazil. CONCLUSION: To maximize benefits of rotavirus vaccination, strategies are needed to improve timeliness of routine immunizations; monitoring rotavirus vaccine uptake and intussusception risk is needed to guide further recommendations for rotavirus vaccination.


Asunto(s)
Programas de Inmunización , Esquemas de Inmunización , Vacunas contra Rotavirus/administración & dosificación , Vacunación/estadística & datos numéricos , Brasil , Preescolar , Vacuna contra Difteria, Tétanos y Tos Ferina/administración & dosificación , Vacunas contra Haemophilus/administración & dosificación , Haemophilus influenzae , Humanos , Lactante , Masculino , Glicoproteínas de Membrana , Rotavirus
7.
Rev Panam Salud Publica ; 30(1): 7-14, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22159645

RESUMEN

OBJECTIVE: To describe an adapted version of the Pan American Health Organization (PAHO) methodology for rapid monitoring of vaccination coverage and its use as a supervisory tool to guide decision-making and strategies for end-stage vaccination activities ("mop-up" operations) following a six-week national rubella elimination campaign in Brazil. METHODS: Vaccination coverage assessments modeled on a variation of PAHO's rapid house-to-house coverage monitoring methodology were conducted by Brazilian municipalities following mass immunization of adults and adolescents from August to December 2008. Results of monitoring assessments conducted in 3 658 (65.7%) of 5 564 municipalities were reported to Brazil's National Immunization Program. RESULTS: Information on vaccination against rubella was obtained from more than 1.5 million Brazilians (2.1% of the 70.1 million people targeted for immunization) during vaccination coverage monitoring. According to the assessment data, vaccination targets of 95% coverage were reached in 2 175 (59.5%) of the 3 658 municipalities that reported results. The percentage of municipalities that reached coverage targets was lower than administrative coverage estimates (number of vaccine doses administered divided by the immunization target population). These results informed targeted "mop-up" campaigns to reach unvaccinated populations. CONCLUSIONS: Rapid coverage monitoring implemented at the local level proved useful for deciding when to conclude vaccination activities and where to focus additional efforts to achieve desired coverage.


Asunto(s)
Programas de Inmunización/estadística & datos numéricos , Vacuna contra el Sarampión-Parotiditis-Rubéola , Vigilancia de la Población/métodos , Rubéola (Sarampión Alemán)/prevención & control , Vacunación/estadística & datos numéricos , Adolescente , Adulto , Brasil/epidemiología , Niño , Femenino , Humanos , Programas de Inmunización/organización & administración , Masculino , Organización Panamericana de la Salud , Salud Urbana , Adulto Joven
8.
J Infect Dis ; 204 Suppl 2: S608-15, 2011 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-21954255

RESUMEN

BACKGROUND: Brazil conducted mass rubella vaccination campaigns to meet disease elimination goals by 2010. An analysis of rubella vaccination opportunities was conducted to target population groups with concentrations of unvaccinated individuals. METHODS: Rubella vaccination strategies for all 27 states were reviewed between 1992 and 2006. Yearly vaccination coverage was calculated by dividing number of doses of measles-rubella or measles-mumps-rubella vaccines administered by census estimates of target populations. For annual birth cohorts (1967-2005), percentages of persons not vaccinated prior to 2007 were estimated by subtracting the highest coverage obtained in any vaccination strategy (routine or campaign) from 100%. Cohort analysis results were compared with rubella incidence by population group. RESULTS: An estimated 28.9 million males and 7.7 million females aged 2-40 years in 2007 remained unvaccinated against rubella, corresponding to 43.0% of males and 11.5% of females of these ages in Brazil. The highest percentages of unvaccinated birth cohorts (93.6%-98.1%) were identified among males aged 26-40 years. In rubella outbreaks reported during 2007, the highest disease incidence (22 cases per 100000 population) occurred among males aged 20-29 years. CONCLUSIONS: Analysis of rubella vaccination opportunities identified concentrations of unvaccinated adults and adolescents for targeting mass vaccination to eliminate rubella and congenital rubella syndrome in Brazil.


Asunto(s)
Vacuna contra la Rubéola/administración & dosificación , Vacuna contra la Rubéola/inmunología , Rubéola (Sarampión Alemán)/epidemiología , Rubéola (Sarampión Alemán)/prevención & control , Adolescente , Adulto , Brasil/epidemiología , Niño , Preescolar , Estudios de Cohortes , Control de Enfermedades Transmisibles , Femenino , Política de Salud , Humanos , Lactante , Masculino , Adulto Joven
9.
Rev. panam. salud pública ; 30(1): 7-14, jul. 2011. ilus, tab
Artículo en Inglés | LILACS | ID: lil-608282

RESUMEN

OBJECTIVE: To describe an adapted version of the Pan American Health Organization (PAHO) methodology for rapid monitoring of vaccination coverage and its use as a supervisory tool to guide decision-making and strategies for end-stage vaccination activities ("mopup" operations) following a six-week national rubella elimination campaign in Brazil. METHODS: Vaccination coverage assessments modeled on a variation of PAHO's rapid house-to-house coverage monitoring methodology were conducted by Brazilian municipalities following mass immunization of adults and adolescents from August to December 2008. Results of monitoring assessments conducted in 3 658 (65.7 percent) of 5 564 municipalities were reported to Brazil's National Immunization Program. RESULTS: Information on vaccination against rubella was obtained from more than 1.5 million Brazilians (2.1 percent of the 70.1 million people targeted for immunization) during vaccination coverage monitoring. According to the assessment data, vaccination targets of 95 percent coverage were reached in 2 175 (59.5 percent) of the 3 658 municipalities that reported results. The percentage of municipalities that reached coverage targets was lower than administrative coverage estimates (number of vaccine doses administered divided by the immunization target population). These results informed targeted "mop-up" campaigns to reach unvaccinated populations. CONCLUSIONS: Rapid coverage monitoring implemented at the local level proved useful for deciding when to conclude vaccination activities and where to focus additional efforts to achieve desired coverage.


Describir una versión adaptada de la metodología de la Organización Panamericana de la Salud (OPS) para el monitoreo rápido de la cobertura de vacunación. Exponer su uso como herramienta de supervisión para guiar la toma de decisiones y las estrategias para las actividades de vacunación finales (campañas "de barrido") después de una campaña nacional de eliminación de la rubéola de 6 semanas de duración en el Brasil. MÉTODOS: Los municipios brasileños llevaron a cabo una evaluación de la cobertura de vacunación basada en una variante de la metodología de monitoreo rápido "casa por casa" de la OPS, después de una campaña masiva de vacunación de adultos y adolescentes efectuada entre agosto y diciembre del 2008. Los resultados de las evaluaciones de seguimiento realizadas en 3 658 (65,7 por ciento) de 5 564 municipios se comunicaron al Programa Nacional de Vacunación del Brasil. RESULTADOS: Mediante el monitoreo de la cobertura de vacunación se obtuvo información sobre la vacunación antirrubeólica de más de 1,5 millones de brasileños (2,1 por ciento de los 70,1 millones de destinatarios de la inmunización). Según estos datos, se alcanzó la meta de vacunación (cobertura del 95 por ciento) en 2 175 (59,5 por ciento) de los 3 658 municipios que presentaron resultados. El porcentaje de municipios que alcanzaron la meta de cobertura fue menor que las estimaciones de cobertura administrativa (cantidad de dosis de vacuna administradas dividida por la población destinataria de la inmunización). Estos resultados se usaron para las campañas de vacunación "de barrido" a fin de alcanzar a las poblaciones no vacunadas. CONCLUSIONES: El monitoreo rápido de la cobertura de vacunación en el nivel local resultó útil para decidir cuándo concluir las actividades de vacunación y en qué aspectos se debían concentrar los esfuerzos posteriores para lograr la cobertura deseada.


Asunto(s)
Humanos , Masculino , Femenino , Niño , Adolescente , Adulto , Adulto Joven , Programas de Inmunización/estadística & datos numéricos , Vacuna contra el Sarampión-Parotiditis-Rubéola , Vigilancia de la Población/métodos , Rubéola (Sarampión Alemán)/prevención & control , Vacunación , Brasil/epidemiología , Programas de Inmunización/organización & administración , Organización Panamericana de la Salud , Salud Urbana
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