Lower ΔFosB expression in the dopaminergic system after stevia consumption in rats housed under environmental enrichment conditions.

Environmental enrichment (EE) has been proven to reduce drug seeking and the development of addiction-related behaviors in rodent models, but the effects of EE on natural reward acquisition in the form of sweet beverages are poorly understood. Accumulating evidence shows that the intake of sugar, the main ingredient of sweet beverages, alters the dopaminergic system, leading to addiction-related physiological and molecular changes. Sugar in sweet beverages has been replaced with natural sweeteners, such as stevia extract, which has greater sweetener potential but no energy content. Our research group found that sucralose consumption increased the expression of ΔFosB in reward-related nuclei, suggesting activation of the dopaminergic system. The present study assessed the effects of EE on stevia consumption and the expression of ΔFosB in the nucleus accumbens, caudate putamen, and prefrontal cortex. Sixteen male Wistar rats, 21 days old, were randomly assigned to an EE group (n = 8) or standard environment (SE) group (n = 8) and reared for 30 days. On postnatal day 52 (PND52), the brains of four animals in each housing condition were extracted to determine basal ΔFosB levels. Stevia consumption with intermittent access and ΔFosB immunoreactivity were measured for 21 days in the remainder of the rats. Compared with SE animals, EE animals exhibited a reduction of stevia consumption and alterations of ΔFosB immunoreactivity in the reward system. These results indicate that EE reduces stevia consumption and the stevia-induced ΔFosB expression, suggesting addiction-related changes in dopaminergic nuclei, which may be interpreted as a neuroprotective effect.

Concordancia interobservador en la evaluación de la escala de desarrollo infantil Bayley II / Matching interobserver assessment scale of child development Bayley II

Un elemento importante en la realización de proyectos de investigación en niños es disminuir el sesgo interobservador al realizar mediciones del desarrollo. Cuando se asegura la validez de un instrumento de evaluación, la magnitud del error se puede determinar a través de estudios de concordancia, que tienen como propósito estimar hasta qué punto dos observadores coinciden en su evaluación. La Escala de Desarrollo Infantil Bayley II (BSID-II) evalúa el desarrollo de los niños de 1 a 42 meses de edad, la prueba consta de tres subescalas diferenciadas: cognoscitiva, psicomotora y de comportamiento. El objetivo del presente estudio fue determinar la concordancia interobservador en la evaluación de la Escala de Desarrollo Infantil Bayley II en niños de 1 a 42 meses de edad. Se realizó un estudio descriptivo de corte transversal con 30 niños nacidos a término sin diagnóstico de enfermedad neurológica, genética o metabólica que acudieron a consulta externa al Laboratorio de Psicobiología durante el periodo comprendido de agosto de 2013 a mayo de 2014. Se documentó la historia clínica y se evaluó con la escala BSID-II a cada participante. Se evaluó la concordancia mediante el test de Kappa media de Cohen con el software Epi dat 4. La prevalencia de retraso global en el desarrollo de los niños fue de 67%, a partir de ello se observó concordancia tanto en las comparaciones del Índice de desarrollo mental k=0.9528, como en el Índice de desarrollo psicomotor k=.9023. El análisis demostró concordancia entre dos profesionistas, lo cual implica que de acuerdo a las categorías no hubo sesgo en el diagnóstico. Este dato es un indicador positivo respecto al nivel de coordinación y la coincidencia en el diagnóstico, además facilita la implementación de tratamientos adecuados para cada uno de los casos evaluados.

An important element when conducting research projects in children is decreasing interobserver bias when making measurements. When the validity of an instrument of evaluation is ensured, the magnitude of error can be determined through studies of concordance, whose purpose is to estimate how much two observers agree in their assessment. The Scale of Infant Development Bayley II evaluates the development of children 1-42 months of age. The test consists of three distinct subscales: cognitive, motor and behavioural. The aim of the present study was to determine interobserver agreement on the implementation of the Bayley Scale of Infant Development (BSID-II, 1993) in children 1-42 months of age. A descriptive cross-sectional study was conducted with 30 children born at term without a diagnosis of neurological, genetic or metabolic diseases that attended external consultation in the lab of Psychobiology during the period august 2013 to May 2014. A clinical history was documented, and the BSDI-II scale was applied, the agreement was assessed by Cohen´s Kappa test mean with Epi dat 4 software. The prevalence of developmental delay in children was 67% concordance was observed in the mental development index k = 0.9528 as well as in the psychomotor development index k = 0.9023. The analysis demonstrated concordance between the two professionals, which means that according to the categories no bias in occurred. This data is a positive indicator with respect to the level of coordination and the agreement in the diagnosis and also facilitates the implementation of an appropriate treatment for each of the cases evaluated.