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1.
Brain Behav ; 14(5): e3517, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38702896

RESUMEN

INTRODUCTION: Attention and working memory are key cognitive functions that allow us to select and maintain information in our mind for a short time, being essential for our daily life and, in particular, for learning and academic performance. It has been shown that musical training can improve working memory performance, but it is still unclear if and how the neural mechanisms of working memory and particularly attention are implicated in this process. In this work, we aimed to identify the oscillatory signature of bimodal attention and working memory that contributes to improved working memory in musically trained children. MATERIALS AND METHODS: We recruited children with and without musical training and asked them to complete a bimodal (auditory/visual) attention and working memory task, whereas their brain activity was measured using electroencephalography. Behavioral, time-frequency, and source reconstruction analyses were made. RESULTS: Results showed that, overall, musically trained children performed better on the task than children without musical training. When comparing musically trained children with children without musical training, we found modulations in the alpha band pre-stimuli onset and the beginning of stimuli onset in the frontal and parietal regions. These correlated with correct responses to the attended modality. Moreover, during the end phase of stimuli presentation, we found modulations correlating with correct responses independent of attention condition in the theta and alpha bands, in the left frontal and right parietal regions. CONCLUSIONS: These results suggest that musically trained children have improved neuronal mechanisms for both attention allocation and memory encoding. Our results can be important for developing interventions for people with attention and working memory difficulties.


Asunto(s)
Ritmo alfa , Atención , Memoria a Corto Plazo , Música , Ritmo Teta , Humanos , Memoria a Corto Plazo/fisiología , Atención/fisiología , Masculino , Femenino , Niño , Ritmo Teta/fisiología , Ritmo alfa/fisiología , Percepción Auditiva/fisiología , Electroencefalografía , Percepción Visual/fisiología , Encéfalo/fisiología
2.
J Biotechnol ; 164(3): 409-22, 2013 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-22698821

RESUMEN

The concept of Elementary Flux Modes (EFMs) has been of central importance in a number of studies involving the analysis of metabolism. In Provost and Bastin (2007) this concept is used to translate the metabolic networks of the different phases of CHO cell cultures into macroscopic bioreactions linking extracellular substrates to products. However, a critical issue concerns the calculation of these elementary flux vectors, as their number combinatorially increases with the size of the metabolic network. In this study, a detailed metabolic network of CHO cells is considered, where the above-mentioned combinatorial explosion makes the computation of the elementary flux modes impossible. To alleviate this problem, a methodology proposed in Jungers et al. (2011) is used to compute a decomposition of admissible flux vectors in a minimal number of elementary flux modes without explicitly enumerating all of them. As a result, a set of macroscopic bioreactions linking the extracellular measured species is obtained at a very low computational expense. The procedure is repeated for the several cell culture phases and a global model is built using a multi-model approach, which is able to successfully predict the evolution of experimental data.


Asunto(s)
Células CHO/metabolismo , Modelos Biológicos , Aminoácidos/metabolismo , Animales , Cricetinae , Cricetulus
3.
J Biotechnol ; 150(4): 497-508, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20869402

RESUMEN

In this article the metabolic flux analysis of growing CHO-320 cells is performed for a detailed metabolic network which involves 100 reactions and embraces all the significant pathways describing the metabolism of CHO cells. The purpose is to investigate the efficiency of the flux analysis when it is based on a relatively small set of extracellular measurements that can be easily achieved in most laboratories. In this case the flux analysis problem leads to a generally underdetermined mass balance system, as data are not sufficient to uniquely define the metabolic fluxes. Our main contribution is to show that, provided the system of mass balance equations is well-posed, although it is underdetermined, very narrow intervals may be found for most fluxes. The importance of checking the well-posedness of the problem is emphasized and the influence of the number of available measurements on the accuracy of the metabolic flux intervals is systematically investigated. In all cases the computed flux intervals are bounded and a single well defined value is obtained for the formation rates of the cellular macromolecules (proteins, DNA, RNA, lipids) that are not measured. The potential gain of a simple theoretical assumption regarding the metabolism of Threonine is also discussed and compared with an optimal solution calculated by maximizing the biomass formation rate. Alternative network structures obtained by inverting the direction of reversible reactions are also considered. Finally, the results of the metabolic flux analysis are exploited to estimate the total energy production resulting from the metabolism of growing CHO-320 cells.


Asunto(s)
Redes y Vías Metabólicas/fisiología , Modelos Biológicos , Treonina/metabolismo , Aminoácidos/metabolismo , Animales , Células CHO , Cricetinae , Cricetulus , Metabolismo de los Lípidos , Nucleótidos/metabolismo , Biosíntesis de Proteínas
4.
Rev. chil. nutr ; 37(3): 309-320, Sept. 2010. ilus, tab
Artículo en Español | LILACS | ID: lil-577397

RESUMEN

In 2008, under the National Plan for Health Promotion and Community Plan for the Promotion of Health, actions to address school obesity by intervening with the Global Strategy Against Obesity schools with the highest obesity prevalence focusing on kindergarten levels (school children between 5-6years) and first grade (students between 6-7 years). The actions of the Community Plan for the Promotion of Health in selected schools of Valparaiso were evaluated. The objectives of this intervention were: 1) assess the nutritional status of children from the participating levels, 2) gather background information on knowledge and behaviors related to food, nutrition and lifestyle in school and 3) identify strengths and difficulties facing the implementation of health policies at local level. We performed a descriptive, non-experimental, non-random convenience sample, which included 267 schools. Results: It was detected 18.8 percent obesity in the transition level (kindergarten and 27 percent in the first grade evaluated according to Technical Standards of the Ministry of Health of Chile based on 2006 WHO reference tables. In order to assess knowledge and behavior, we developed and applied the tools "Caritas" and "Healthier Snacks" observing 77 percent and 87 percent and 90 percent and 64 percent of correct associations for knowledge and behaviors, respectively. Facilitators: cooperative work and valuation from education. Barriers: outdated actions altering school curriculum planning. Figures of malnutrition by excess and the difficulty to reverse this reality require programs to in identify nutritional knowledge and eating behaviors of the population.


En el 2008, en el marco del Plan Nacional de Promoción de la Salud y del Plan Comunal de Promoción de la Salud se priorizan acciones para abordar la obesidad escolar interviniendo con la Estrategia Global contra la Obesidad las escuelas con los más altos índices de obesidad a nivel comunal, focalizando en escolares de kinder (escolares entre 5-6 años de edad) y primer año básico (escolares entre 6-7 años de edad). En Valparaíso, se evaluaron las acciones del Plan Comunal de Promoción de la Salud en 3 de las 4 Escuelas seleccionadas. Los objetivos de esta intervención fueron; 1) evaluar el estado nutricional de los niños/niñas de los niveles participantes; 2) recopilar antecedentes sobre conocimientos y conductas asociadas a la alimentación y nutrición y estilos de vida en los escolares de kinder y primer año básico y 3) identificar dificultades y fortalezas que enfrentan la implementación de las políticas sanitarias a nivel local. Se realizó un estudio descriptivo, diseño no experimental, muestra intencionada no aleatoria. La muestra incluyó a 267 escolares. Resultados; se detectó 18,8 por ciento obesidad en el nivel de transición mayor y 27 por ciento en el primer año básico evaluados según Normas Técnicas del Ministerio de Salud de Chile (MTNSAL) en base a la referencia de la OMS 2006; para evaluar conocimientos y conductas los autores elaboraron y aplicáronlos instrumentos "Caritas" y "Colaciones más saludables". Se observó un 77 por ciento y 87 por ciento; y 90 por ciento y 64 por ciento de asociaciones correctas para conocimientos y conductas, respectivamente. Facilitadores; trabajo intersectorial y valoración desde educación; obstaculizadores; acciones desfasadas que alteran la planificación curricular de las escuelas. Las cifras de malnutrición por exceso y la dificultad para revertir esta realidad, requiere avanzar en identificar conocimientos y conductas alimentarias nutricionales en la población.


Asunto(s)
Humanos , Masculino , Femenino , Niño , Conducta Infantil , Conducta Alimentaria , Conocimientos, Actitudes y Práctica en Salud , Chile , Promoción de la Salud , Estado Nutricional , Obesidad/epidemiología , Obesidad/prevención & control , Servicios de Salud Escolar , Alimentos Integrales
6.
Enfermedades respir. cir. torac ; 2(4): 132-8, oct.-dic. 1986. tab
Artículo en Español | LILACS | ID: lil-65902

RESUMEN

Se analizan diversos parámetros antropométicos, físicos y la C.V. de 131 trabajadores varones residentes en altura (2.400-2.800 m.s.n.m.),encontrándose una C.V. significativamente mayor que la de grupos comparables obtenidas por investigadores extranjeros y la de un estudio nacional realizado en trabajadores que residen en Santiago (450 m.s.n.m.) se infiere que las normas actualmente en uso no son confiables para la evaluación de la normalidad o anormalidad de la función pulmonar de la población trabajadora chilena. Mediante análisis computacional se determinó la ecuación de regresión múltiple para la C.V., en relación con las variables independientes edad y estatura, para población masculina, trabajadora, sana y que reside a una altitud calificada como moderada. Esta fórmula es: C.V.(1)=0,0848 por talla (cm)- 0,016 por edad (años)- 8,51; que es diferente a la encontrada por Kory y cols. que es la norma de referencia en la evaluación médico-legal de las enfermedades respiratorias ocupacionales. La aplicación de esta norma puede originar considerables errores, especialmente en sujetos residentes de altura. Se postula que dentro de los factores que pueden incidir en el valor de la C.V. de trabajadores, debe considerarse la altura a la cual residen y su correspondiente presión barométrica. Esto se desprende de cuatro estudios nacionales realizados a diferentes altitudes y en los cuales la C.V. de los sujetos aumenta a medida que la presión barométrica disminuye. La C.V.F. fue mayor en los sujetos que realizaban actividad física habitual, al igual que lo que ocurre a nivel del mar, donde los deportistas tienen valores significativamente superiores a grupos comparables de la población general


Asunto(s)
Adulto , Persona de Mediana Edad , Humanos , Masculino , Altitud , Capacidad Vital , Antropometría , Espirometría
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