Dopamine-Induced Ascorbate Release From Retinal Neurons Involves Glutamate Release, Activation of AMPA/Kainate Receptors and Downstream Signaling Pathways

Ascorbate, the reduced form of Vitamin C, is one of the most abundant and important low-molecular weight antioxidants in living tissues. Most animals synthesize vitamin C, but some primates, including humans, have lost this capacity due to disruption in L-gulono-gamma-lactone oxidase gene. Because of this incapacity, those animals must obtain Vitamin C from the diet. Ascorbate is highly concentrated in the central nervous system (CNS), including the retina, and plays essential roles in neuronal physiology. Ascorbate transport into cells is controlled by Sodium Vitamin C Co-Transporters (SVCTs). There are four SVCT isoforms and SVCT2 is the major isoform controlling ascorbate transport in the CNS. Regarding ascorbate release from retinal neurons, Glutamate, by activating its ionotropic receptors leads to ascorbate release via the reversion of SVCT2. Moreover, dopamine, via activation of D1 receptor/cyclic AMP/EPAC2 pathway, also induces ascorbate release via SVCT2 reversion. Because the dopaminergic and glutamatergic systems are interconnected in the CNS, we hypothesized that dopamine could regulate ascorbate release indirectly, via the glutamatergic system. Here we reveal that dopamine increases the release of D-Aspartate from retinal neurons in a way independent on calcium ions and dependent on excitatory amino acid transporters. In addition, dopamine-dependent SVCT2 reversion leading to ascorbate release occurs by activation of AMPA/Kainate receptors and downstream ERK/AKT pathways. Overall, our data reveal a dopamine-to-glutamate signaling that regulates the bioavailability of ascorbate in neuronal cells

Influência da expressão e educação físico motora no desenvolvimento da criança do 1º ciclo do ensino básico : contextos, perspetivas e participantes

A formação global da criança, na qual se integra a formação motora, deve ocupar um lugar de relevância na escola atual. Neste espaço, os alunos constroem o seu próprio conhecimento, e ao vivenciarem as aprendizagens de forma lúdica, potenciam o desenvolvimento de outras competências. O presente Relatório Final de Estágio encontra-se dividido em duas partes distintas: as reflexões críticas das práticas em contexto e o trabalho de investigação. Na primeira parte é apresentada uma apreciação crítica das práticas em contexto prático, nomeadamente na educação pré-escolar e do ensino do 1.º CEB. Na segunda parte damos a conhecer o trabalho de investigação, baseado num estudo de natureza quantitativa realizado no contexto de 1.º CEB de um Agrupamento de Escolas de Aveiro e de um Agrupamento de Escolas de Viseu que visa compreender a influência da Expressão e Educação Físico-Motora no desenvolvimento global da criança. Para o efeito, recorremos a autores de referência e à legislação em vigor, assim como, em termos empíricos, as respostas aos questionários dirigidos aos professoras do 1.º CEB. Os resultados encontrados apontam para o seguinte conjunto de principais conclusões: 1.º os professores atribuem muita importância às práticas motoras, constituindo-se como um fator fundamental para o desenvolvimento integral e harmonioso da criança; 2.º a Expressão e Educação Físico-Motora não têm sido uma realidade nas escolas do estudo, os professores apresentam como principais causas: a falta de condições de materiais, espaciais e de equipamentos como também a necessidade de formação, quer a nível da formação inicial quer a nível da formação contínua; 3.º os agrupamentos, as escolas e os professores devem estar implicados nos diferentes contextos nos quais circula a criança e que são promotores de formação e desenvolvimento, tanto ao nível dos quadros letivos e curriculares como também nos de enriquecimento curricular e nos projetos mais lúdicos e de recreação; 4.º a Expressão e Educação Físico-Motora deve assumir claramente o seu carácter formativo, onde a iniciativa e responsabilidade na organização deve ir ao encontro das aspirações das crianças e de toda a comunidade educativa.The overall formation of the child, in which the motor formation is integrated, must occupy a place of relevance in the present school. In this space, students construct their own knowledge, and when they experience learning in a playful way, they foster the development of other skills. This Final Internship Report is divided into two distinct parts: the critical reflections of the practices and the research work. The first part presents a critical appraisal of practices in a practical context, namely in pre-school education and 1st cycle education (1st CEB). In the second part it is presented the research work, based on a quantitative study carried out in the context of 1st CEB in two schools from Aveiro and Viseu Portuguese Grouping of Schools that aims to understand the influence of physical-motor expression in the overall development of the child. To this end, authors of reference and legislation in force, as well as, in empirical terms, the answers to the questionnaires addressed to the teachers of the 1st CEB were used as methodology to reach the desirable goal. The results lead to the following set of main conclusions: 1) teachers attach great importance to motor practices, constituting as a fundamental factor for the integral and harmonious development of the child; 2) physical-motor expression have not been a reality in the schools of the study, the main causes of teachers are: the lack of material, space and equipment conditions as well as the need for training, both in training Initial or continuing training; 3) groups, schools and teachers must be involved in the different contexts in which the child circulates and are promoters of training and development, both in terms of school and curricular frameworks as well as curriculum enrichment and more playful projects and recreation; 4) expression and physical-motor education must clearly assume its formative character, where the initiative and responsibility in the organization must meet the aspirations of the children and the entire educational community

Diagnosis, Prognosis and Treatment of Canine Cutaneous and Subcutaneous Mast Cell Tumors

Mast cell tumors (MCTs) are hematopoietic neoplasms composed of mast cells. It is highly common in dogs and is extremely important in the veterinary oncology field. It represents the third most common tumor subtype, and is the most common malignant skin tumor in dogs, corresponding to 11% of skin cancer cases. The objective of this critical review was to present the report of the 2nd Consensus meeting on the Diagnosis, Prognosis, and Treatment of Canine Cutaneous and Subcutaneous Mast Cell Tumors, which was organized by the Brazilian Association of Veterinary Oncology (ABROVET) in August 2021. The most recent information on cutaneous and subcutaneous mast cell tumors in dogs is presented and discussed