Coping with unpredictability: Dopaminergic and neurotrophic responses to omission of expected reward in Atlantic salmon (Salmo salar L.).

Comparative studies are imperative for understanding the evolution of adaptive neurobiological processes such as neural plasticity, cognition, and emotion. Previously we have reported that prolonged omission of expected rewards (OER, or 'frustrative nonreward') causes increased aggression in Atlantic salmon (Salmo salar). Here we report changes in brain monoaminergic activity and relative abundance of brain derived neurotrophic factor (BDNF) and dopamine receptor mRNA transcripts in the same paradigm. Groups of fish were initially conditioned to associate a flashing light with feeding. Subsequently, the expected food reward was delayed for 30 minutes during two out of three meals per day in the OER treatment, while the previously established routine was maintained in control groups. After 8 days there was no effect of OER on baseline brain stem serotonin (5-HT) or dopamine (DA) activity. Subsequent exposure to acute confinement stress led to increased plasma cortisol and elevated turnover of brain stem DA and 5-HT in all animals. The DA response was potentiated and DA receptor 1 (D1) mRNA abundance was reduced in the OER-exposed fish, indicating a sensitization of the DA system. In addition OER suppressed abundance of BDNF in the telencephalon of non-stressed fish. Regardless of OER treatment, a strong positive correlation between BDNF and D1 mRNA abundance was seen in non-stressed fish. This correlation was disrupted by acute stress, and replaced by a negative correlation between BDNF abundance and plasma cortisol concentration. These observations indicate a conserved link between DA, neurotrophin regulation, and corticosteroid-signaling pathways. The results also emphasize how fish models can be important tools in the study of neural plasticity and responsiveness to environmental unpredictability

Retinyl palmitate flexible polymeric nanocapsules: Characterization and permeation studies

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Polymeric nanocapsules with elastic characteristics were prepared by the pre-formed polymer interfacial deposition method. The system consists of an oily core of retinyl paimitate with Span 60 and a polymeric wall of poly(D,L-lactide) (PLA). A narrow size distribution (215 nm, P.D.I. 0.10) was showed by dynamic light scattering (DLS) analyses. Particle deformability was observed by transmission electron microscopy (TEM) images and permeation of the particles through two superposed membranes of smaller pore diameters. Permeation studies were achieved using plastic surgery abdominal human skin by Franz diffusion cell. Retinyl palmitate permeates into deep skin layers. Besides, a PLA fluorescent derivative conjugated with Nile blue dye by an amide covalent bound was additionally obtained. Permeation profile of the nanocapsules with the fluorescent polymer was evaluated by confocal laser scanning microscopy (CLSM). The CLSM showed that nanocapsules were distributed uniformly, suggesting that the permeation mechanism through skin is intercellular. Thus, the use of these nanocapsules may be a feasible strategy to enhance the permeation of actives into the skin when delivery to deep layers is aimed. (C) 2010 Elsevier B.V. All rights reserved.811374380Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

A vivência de mães de recém-nascidos prematuros no processo de lactação e amamentação La vivencia de las madres de recién nacidos prematuros en el proceso de la lactación y de amamentación The living of preterm newborn's mother in the process of lactation and breastfeeding

Este estudo qualitativo teve como objetivo geral compreender a vivência da amamentação de mães de recém-nascidos prematuros durante a internação de seus filhos e como objetivo específico descrever a performance de amamentação e condições de suas mamas e lactação, por ocasião da alta dos filhos. Adotaram-se o modelo Pesando Riscos e Benefícios como referencial de análise e o método do Discurso do Sujeito Coletivo para organização dos dados. Participaram do estudo 11 mulheres, mães de bebês prematuros internados na Unidade Neonatal do HU-USP. A entrevista semiestruturada possibilitou a elaboração de oito Discursos do Sujeito Coletivo listados em dois blocos com os seguintes temas: "Lactação e amamentação" e "Contexto hospitalar e doméstico", que possibilitaram de compreensão de que as mães deste estudo vivenciam um processo de avaliação contínua das condições de saúde, crescimento e desenvolvimento da criança, que contribui para sua motivação para amamentar e direciona suas ações no prosseguimento da amamentação.<br>Este estudio cualitativo ha tenido como objetivo general, comprender la vivencia de amamentación de madres de recién nacidos prematuros, durante la internación de sus hijos y como objetivos específicos describir el desempeño de la amamantación y condiciones de sus mamas y lactación, en el momento del alta de sus hijos. Se ha adoptado el modelo: Pesando riesgos y beneficios, como referencial de análisis y el método del Discurso del Sujeto Colectivo para organización de los datos. Han participado del estudio 11 mujeres, madres de bebes prematuros, internados en La Unidad Neonatal del HU-USP. La entrevista semi estructurada ha posibilitado la elaboración de ocho Discursos del Sujeto Colectivo listados en dos bloques con los siguientes temas: Lactación y Amamantación y Contexto de hospital y doméstico, que han posibilitado comprender, que las madres de este estudio han vivenciado un proceso de avaluación continuado de las condiciones de salud, crecimiento y desarrollo del niño que ha contribuido para su motivación en amamantar y que ha diseccionado sus acciones en el proseguimiento de la amamantación.<br>This qualitative study aimed on the whole to understand the breastfeeding living experience of preterm newborn's mothers, throughout the admission of their children and as specific objectives to describe the breastfeeding performance, and their lactation and breasts' conditions during their children's hospital discharge. It was adopted the model Weighing Risks and Benefits, as analysis referential and the method of Collective Subject for organizing data. Eleven women attended the study, in which they were mothers of preterm infants admitted at the Neonatal Unit of HU-USP. The semi-structured interview made it possible the creation of eight Collective Subject Discourses, listed in two groups with the following themes: Lactation and breastfeeding and Hospital and home contexts, which made it possible to understand that the mothers of this study lived a process of ongoing evaluation of the child's health, growth and development conditions, which contributes to their motivation to breastfeed and guides their actions in keeping breastfeeding