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1.
Bol Med Hosp Infant Mex ; 80(1): 3-14, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36867568

RESUMEN

In February 2016, the World Health Organization declared Zika virus (ZIKV) infection a public health emergency of international concern because it caused congenital Zika syndrome (CZS). The CZS is considered a specific pattern of birth defects caused by ZIKV infection, which is transmitted by the bite of the Aedes aegypti mosquito. The CZS clinical manifestations are broad and nonspecific, including microcephaly, subcortical calcifications, ocular alterations, congenital contractures, early hypertonia, and pyramidal as well as extrapyramidal symptoms. The ZIKV has gained great importance because it has affected a large percentage of the population worldwide during the last few years, despite the measures implemented by international organizations. The pathophysiology and non-vectorial transmission routes of the virus are still under study. The diagnosis is made upon suspicion of ZIKV infection, the patient's clinical manifestations, and it is confirmed by molecular laboratory tests demonstrating the presence of viral particles. Unfortunately, there is no specific treatment or vaccine for this condition; however, patients receive multidisciplinary care and constant monitoring. Therefore, the strategies that have been implemented are directed toward preventive measures and vector control.


En febrero de 2016, la Organización Mundial de la Salud declaró a la infección por virus Zika una emergencia de salud pública de importancia internacional por ser la causa del síndrome congénito por virus Zika. Este síndrome es considerado un patrón específico de defectos al nacimiento causados por la infección por virus Zika, que se transmite por la picadura del mosquito vector Aedes aegypti y cuyas manifestaciones clínicas son amplias e inespecíficas, entre las que destacan microcefalia, calcificaciones subcorticales, alteraciones oculares, contracturas congénitas, hipertonía temprana y síntomas de afectación piramidal y extrapiramidal. Este virus ha tomado gran importancia debido a que durante los últimos años ha afectado a un gran porcentaje de la población en todo el mundo, a pesar de las medidas implementadas por organizaciones internacionales. La fisiopatología y las vías de transmisión no vectorial de la infección aún siguen en estudio. El diagnóstico se realiza ante la sospecha por las manifestaciones clínicas del paciente, y se confirma mediante pruebas moleculares de laboratorio en las que se demuestre la presencia de partículas virales. Desafortunadamente, no existe aún un tratamiento ni una vacuna específica para este padecimiento; sin embargo, los pacientes reciben cuidados multidisciplinarios y monitorización constante. Las estrategias que se han implementado se dirigen hacia medidas preventivas de la infección y el control de los vectores.


Asunto(s)
Microcefalia , Infección por el Virus Zika , Virus Zika , Animales , Humanos
2.
Bol. méd. Hosp. Infant. Méx ; 80(1): 3-14, Jan.-Feb. 2023. tab, graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1429935

RESUMEN

Abstract In February 2016, the World Health Organization declared Zika virus (ZIKV) infection a public health emergency of international concern because it caused congenital Zika syndrome (CZS). The CZS is considered a specific pattern of birth defects caused by ZIKV infection, which is transmitted by the bite of the Aedes aegypti mosquito. The CZS clinical manifestations are broad and nonspecific, including microcephaly, subcortical calcifications, ocular alterations, congenital contractures, early hypertonia, and pyramidal as well as extrapyramidal symptoms. The ZIKV has gained great importance because it has affected a large percentage of the population worldwide during the last few years, despite the measures implemented by international organizations. The pathophysiology and non-vectorial transmission routes of the virus are still under study. The diagnosis is made upon suspicion of ZIKV infection, the patient's clinical manifestations, and it is confirmed by molecular laboratory tests demonstrating the presence of viral particles. Unfortunately, there is no specific treatment or vaccine for this condition; however, patients receive multidisciplinary care and constant monitoring. Therefore, the strategies that have been implemented are directed toward preventive measures and vector control.


Resumen En febrero de 2016, la Organización Mundial de la Salud declaró a la infección por virus Zika una emergencia de salud pública de importancia internacional por ser la causa del síndrome congénito por virus Zika. Este síndrome es considerado un patrón específico de defectos al nacimiento causados por la infección por virus Zika, que se transmite por la picadura del mosquito vector Aedes aegypti y cuyas manifestaciones clínicas son amplias e inespecíficas, entre las que destacan microcefalia, calcificaciones subcorticales, alteraciones oculares, contracturas congénitas, hipertonía temprana y síntomas de afectación piramidal y extrapiramidal. Este virus ha tomado gran importancia debido a que durante los últimos años ha afectado a un gran porcentaje de la población en todo el mundo, a pesar de las medidas implementadas por organizaciones internacionales. La fisiopatología y las vías de transmisión no vectorial de la infección aún siguen en estudio. El diagnóstico se realiza ante la sospecha por las manifestaciones clínicas del paciente, y se confirma mediante pruebas moleculares de laboratorio en las que se demuestre la presencia de partículas virales. Desafortunadamente, no existe aún un tratamiento ni una vacuna específica para este padecimiento; sin embargo, los pacientes reciben cuidados multidisciplinarios y monitorización constante. Las estrategias que se han implementado se dirigen hacia medidas preventivas de la infección y el control de los vectores.

4.
Appl Microbiol Biotechnol ; 105(8): 3075-3086, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33818671

RESUMEN

Hyaluronic acid (HA) is a high value glycosaminoglycan mostly used in health and cosmetic applications. Commercial HA is produced from animal tissues or in toxigenic bacteria of the genus Streptococcus grown in complex media, which are expensive and raise environmental concerns due to the disposal of large amounts of broth with high organic loads. Other microorganisms were proposed as hosts for the heterologous production of HA, but the methods are still costly. The extraordinary capacity of this biopolymer to bind and retain water attracts interest for large-scale applications where biodegradable materials are needed, but its high cost and safety concerns are barriers for its adoption. Bacillus subtilis 3NA strain is prototrophic, amenable for genetic manipulation, GRAS, and can rapidly reach high cell densities in salt-based media. These phenotypic traits were exploited to create a platform for biomolecule production using HA as a proof of concept. First, the 3NA strain was engineered to produce HA; second, a chemically defined medium was formulated using commodity-priced inorganic salts combined at the stoichiometric ratios needed to build the necessary quantities of biomass and HA; and third, a scalable fermentation process, where HA can be produced at the maximum volumetric productivity (VP), was designed. A comparative economic analysis against other methods indicates that the new process may increase the operating profit of a manufacturing plant by more than 100%. The host, the culture medium, and the rationale employed to develop the fermentation process described here, introduce an IP-free platform that could be adaptable for production of other biomolecules. KEY POINTS: • A biomolecule production platform based on B. subtilis 3NA strain and a synthetic medium was tested for hyaluronic acid biosynthesis • A fermentation process with the maximum volumetric productivity was designed • A techno-economic analysis forecasts a significant reduction in the manufacturing cost compared to the current methods.


Asunto(s)
Bacillus subtilis , Ácido Hialurónico , Animales , Bacillus subtilis/genética , Medios de Cultivo , Fermentación , Streptococcus
5.
Educ Psychol Rev ; 33(4): 1379-1407, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33716467

RESUMEN

Researchers of cognitive load theory and the cognitive theory of multimedia learning have identified several strategies to optimize instructional materials. In this review article we focus on five of these strategies or solutions to problematic instructional designs in multimedia learning: (a) the multimedia principle (use visualizations and drawings to complement texts); (b) the split-attention effect or spatial contiguity principle (show texts contiguously or integrated with visualizations); (c) the redundancy effect, alike the coherence principle (remove nonessential learning information); (d) the signaling principle (cue or signal essential learning information); and (e) the transient information effect or segmenting principle (segment or control the pace of animations and videos). Usually, both cognitive theories have investigated solutions that instructors, teachers, and designers should pursue to optimize students' learning. Here, in a novel approach, we show that these strategies can also be used by learners who want to self-manage their cognitive load and learning process. We provide several examples of both instructor- and learner-managed solutions aligned with these strategies. When assessing which agent, either the instructor or the learner, was most effective, we observed mixed results in the literature. However, the expertise reversal effect may help predict the direction of these effects: novice students may learn better under instructor-managed conditions, whereas more expert students may learn more under learner-managed conditions.

6.
Neotrop. ichthyol ; 16(1): [e170130], mar. 2018. tab, graf
Artículo en Inglés | VETINDEX | ID: vti-18604

RESUMEN

The goliath catfish Brachyplatystoma rousseauxii has crucial economical and ecological functions in the Amazon basin. Although its life history characteristics have been studied in the Amazon, there is little information in the Madeira River basin, which holds genetically distinct populations and where dams were recently built. Using fish collected in Bolivia, Brazil and Peru, this study provides a validation of growth rings deposition and details the growth patterns of B. rousseauxii in the Madeira before the dams' construction. Age structure and growth parameters were determined from 497 otolith readings. The species exhibits two growth rings per year and sampled fish were between 0 and 16 years old. In the Brazilian portion of the basin, mainly young individuals below 5 years old were found, whereas older fish (> 5 years) were caught only in the Bolivian and Peruvian stretches, indicating that after migrating upstream to reproduce, adults remain in the headwaters of the Madeira River. Comparing with previous publications, B. rousseauxii had a slower growth and 20 cm lower maximum standard length in the Madeira River than in the Amazon River. This study provides a baseline for future evaluation of changes in population dynamics of the species following dams closure.(AU)


Brachyplatystoma rousseauxii é um bagre de importante papel econômico e ecológico na bacia amazônica. Embora existam estudos acerca de sua história de vida na Amazônia, há pouca informação para a bacia do rio Madeira, onde existem populações geneticamente distintas e recentemente foram construídas duas usinas hidrelétricas. Este estudo validou a deposição das marcas de crescimento e detalhou os padrões de desenvolvimento dessa espécie no rio Madeira, antes da construção das barragens. As coletas abrangeram os territórios brasileiro, boliviano e peruano, com estrutura etária e parâmetros de crescimento determinados a partir de 497 otólitos. Foram observadas duas marcas de crescimento por ano e indivíduos entre 0 e 16 anos. Na porção brasileira foram encontrados principalmente jovens menores de 5 anos, enquanto que os peixes mais velhos (> 5 anos) foram capturados apenas na Bolívia e Peru, indicando que após a migração reprodutiva, os adultos permanecem nas cabeceiras do rio Madeira. Comparando com estudos prévios realizados na calha principal do rio Amazonas, B. rousseauxii apresentou crescimento mais lento e comprimento padrão máximo inferior de 20 cm no rio Madeira. Este estudo fornece uma base para a avaliação futura das mudanças na dinâmica populacional desse espécie após o implementação das barragens.(AU)


Asunto(s)
Animales , Bagres/crecimiento & desarrollo , Estadios del Ciclo de Vida , Bagres/genética , Membrana Otolítica/anatomía & histología
7.
Neotrop. ichthyol ; 16(1): e170130, 2018. tab, graf
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-895132

RESUMEN

The goliath catfish Brachyplatystoma rousseauxii has crucial economical and ecological functions in the Amazon basin. Although its life history characteristics have been studied in the Amazon, there is little information in the Madeira River basin, which holds genetically distinct populations and where dams were recently built. Using fish collected in Bolivia, Brazil and Peru, this study provides a validation of growth rings deposition and details the growth patterns of B. rousseauxii in the Madeira before the dams' construction. Age structure and growth parameters were determined from 497 otolith readings. The species exhibits two growth rings per year and sampled fish were between 0 and 16 years old. In the Brazilian portion of the basin, mainly young individuals below 5 years old were found, whereas older fish (> 5 years) were caught only in the Bolivian and Peruvian stretches, indicating that after migrating upstream to reproduce, adults remain in the headwaters of the Madeira River. Comparing with previous publications, B. rousseauxii had a slower growth and 20 cm lower maximum standard length in the Madeira River than in the Amazon River. This study provides a baseline for future evaluation of changes in population dynamics of the species following dams closure.(AU)


Brachyplatystoma rousseauxii é um bagre de importante papel econômico e ecológico na bacia amazônica. Embora existam estudos acerca de sua história de vida na Amazônia, há pouca informação para a bacia do rio Madeira, onde existem populações geneticamente distintas e recentemente foram construídas duas usinas hidrelétricas. Este estudo validou a deposição das marcas de crescimento e detalhou os padrões de desenvolvimento dessa espécie no rio Madeira, antes da construção das barragens. As coletas abrangeram os territórios brasileiro, boliviano e peruano, com estrutura etária e parâmetros de crescimento determinados a partir de 497 otólitos. Foram observadas duas marcas de crescimento por ano e indivíduos entre 0 e 16 anos. Na porção brasileira foram encontrados principalmente jovens menores de 5 anos, enquanto que os peixes mais velhos (> 5 anos) foram capturados apenas na Bolívia e Peru, indicando que após a migração reprodutiva, os adultos permanecem nas cabeceiras do rio Madeira. Comparando com estudos prévios realizados na calha principal do rio Amazonas, B. rousseauxii apresentou crescimento mais lento e comprimento padrão máximo inferior de 20 cm no rio Madeira. Este estudo fornece uma base para a avaliação futura das mudanças na dinâmica populacional desse espécie após o implementação das barragens.(AU)


Asunto(s)
Animales , Bagres/genética , Bagres/crecimiento & desarrollo , Estadios del Ciclo de Vida , Membrana Otolítica/anatomía & histología
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