Ex situ collection of Limonium spp.: cytogenetic and reproductive characterization for the conservation of rare species

Dissertação mestrado em Biologia Molecular, Biotecnologia e Bioempreendedorismo em Plantas

O filme “A Gaiola Dourada”: reflexões sobre o regresso em força da emigração portuguesa e a ‘portugalidade’ de uma gaiola (cada vez menos) dourada

A história de um casal de emigrantes portugueses em França bateu, no verão de 2013, recordes de audiência nas salas de cinema. O filme “A Gaiola Dourada”, de Ruben Alves, recuperou a temática da emigração portuguesa, numa altura em que esta atingiu o boom registado nos anos 1960. Recorrendo ao seu percurso, o realizador refere-se à ‘portugalidade’ como alegada ‘pertença a Portugal’, que assume como um cliché, e utiliza de forma humorística vários estereótipos associados aos emigrantes portugueses, através dos quais é mostrada alguma vergonha que os filhos dos emigrantes sentem em relação ao comportamento dos pais, trazendo ao de cima os contrastes com a sociedade onde vivem. A grande ficção reside no regresso ao país de origem, concretizando o sonho da grande maioria dos emigrantes, mas subvertendo a lógica: no filme, não são os pais que voltam a Portugal, mas os filhos, que aparentemente pouco se identificam com o país dos progenitores. “A Gaiola Dourada” reintroduziu o debate sobre a emigração em Portugal, aproveitando a crise económica para refletir sobre o seu regresso em força, bem como traçar o perfil dos novos emigrantes. Será que os portugueses na ‘diáspora’ ainda reavivam a chama ‘lusitana’ (Gonçalves, 2009)? E será que a partilha do nome ‘Portugal’ basta para sublinhar uma alegada identidade nacional (Sobral, 2012)?

Mesenchymal stem cells secretome as a modulator of the neurogenic niche: Basic insights and therapeutic opportunities

Neural stem cells (NSCs) and mesenchymal stem cells (MSCs) share few characteristics apart from self-renewal and multipotency. In fact, the neurogenic and osteogenic stem cell niches derive from two distinct embryonary structures; while the later originates from the mesoderm, as all the connective tissues do, the first derives from the ectoderm. Therefore, it is highly unlikely that stem cells isolated from one niche could form terminally differentiated cells from the other. Additionally, these two niches are associated to tissues/systems (e.g., bone and central nervous system) that have markedly different needs and display diverse functions within the human body. Nevertheless they do share common features. For instance, the differentiation of both NSCs and MSCs is intimately associated with the bone morphogenetic protein family. Moreover, both NSCs and MSCs secrete a panel of common growth factors, such as nerve growth factor (NGF), glial derived neurotrophic factor (GDNF), and brain derived neurotrophic factor (BDNF), among others. But it is not the features they share but the interaction between them that seem most important, and worth exploring; namely, it has already been shown that there are mutually beneficially effects when these cell types are co-cultured in vitro. In fact the use of MSCs, and their secretome, become a strong candidate to be used as a therapeutic tool for CNS applications, namely by triggering the endogenous proliferation and differentiation of neural progenitors, among other mechanisms. Quite interestingly it was recently revealed that MSCs could be found in the human brain, in the vicinity of capillaries. In the present review we highlight how MSCs and NSCs in the neurogenic niches interact. Furthermore, we propose directions on this field and explore the future therapeutic possibilities that may arise from the combination/interaction of MSCs and NSCs.