The manipulation of endogenous stem cell populations from the subventricular zone (SVZ), a neurogenic niche, creates an opportunity to induce neurogenesis and influence brain regenerative capacities in the adult brain. Herein, we demonstrate the ability of polyelectrolyte nanoparticles to induce neurogenesis exclusively after being internalized by SVZ stem cells. The nanoparticles are not cytotoxic for concentrations equal or below 10 μg/mL. The internalization process is rapid, and nanoparticles escape endosomal fate in a few hours. Retinoic acid-loaded nanoparticles increase the number of neuronal nuclear protein (NeuN)-positive neurons and functional neurons responding to depolarization with KCl and expressing NMDA receptor subunit type 1 (NR1). These nanoparticles offer an opportunity for in vivo delivery of proneurogenic factors and neurodegenerative disease treatment.

Extracellular matrix (ECM) proteins play a key role during oligodendrogenesis. While fibronectin (FN) is involved in the maintenance and proliferation of oligodendrocyte progenitor cells (OPCs), merosin (MN) promotes differentiation into oligodendrocytes (OLs). Mechanical properties of the ECM also seem to affect OL differentiation, hence this study aimed to clarify the impact of combined biophysical and biochemical elements during oligodendrocyte differentiation and maturation using synthetic elastic polymeric ECM-like substrates. CG-4 cells presented OPC- or OL-like morphology in response to brain-compliant substrates functionalised with FN or MN, respectively. The expression of the differentiation and maturation markers myelin basic protein — MBP — and proteolipid protein — PLP — (respectively) by primary rat oligodendrocytes was enhanced in presence of MN, but only on brain-compliant conditions, considering the distribution (MBP) or amount (PLP) of the protein. It was also observed that maturation of OLs was attained earlier (by assessing PLP expression) by cells differentiated on MN-functionalised brain-compliant substrates than on standard culture conditions. Moreover, the combination of MN and substrate compliance enhanced the maturation and morphological complexity of OLs. Considering the distinct degrees of stiffness tested ranging within those of the central nervous system, our results indicate that 6.5 kPa is the most suitable rigidity for oligodendrocyte differentiation.

The subventricular zone (SVZ) and the hippocampal subgranular zone (SGZ) comprise two main germinal niches in the adult mammalian brain. Within these regions there are self-renewing and multipotent neural stem cells (NSCs) which can ultimately give rise to new neurons, astrocytes and oligodendrocytes. Understanding how to efficiently trigger NSCs differentiation is crucial to devise new cellular therapies aimed to repair the damaged brain. A large amount of data ranging from epigenetic alterations, chromatin remodelling and signalling pathways involved in NSCs differentiation are now within reach. Furthermore, a vast array of proteins and molecules have been described to modulate NSCs fate and tested in innovative therapeutic applications, however with little success so far. Nowadays, the main focus is on how to manipulate these factors to our full advantage. Unfortunately, concerns related to solubility, stability, concentration or spatial and temporal positioning can hinder their desirable effects. Biomaterials emerge as the ideal support to overcome these limitations and consequently boost NSCs differentiation towards desired phenotypes. However, the balance between biomaterials and differentiating factors must be well established, since the bioaccumulation and concomitant toxicity can be an undesired side-effect. Currently, innovative materials and formulations including more degradable carriers allow a controlled and efficient release of bioactive factors with minimal side-effects. Recently, micro- and nanoparticles have been successfully used to deliver molecules able to induce neurogenesis. This review presents recent research that highlights the role of both extracellular environmental factors as well as molecular remodelling mechanisms in the control of NSCs differentiation processes. Appropriate biomaterials that may trigger an efficient delivery of therapeutic molecules will be also discussed. Therefore, the interface between NSCs biology and tissue engineering may offer great potential in future therapeutics for treatment or amelioration of neurodegenerative diseases or brain injury.

Este artigo tem como objetivo fazer uma revisitação do franchising He-man and the Masters of the Universe, um universo recreativo que se estendeu a várias áreas de negócio. Tratando-se de um universo concebido no contexto da tecnocultura dos anos 80, recebeu a influência de vários elementos culturais e ideológicos que justificam a sua classificação como representação do pós-humano. Inclusivamente, as representações de He-man em décadas posteriores não deixaram de revelar elementos interessantes para o estudo académico das recriações do pós-humano face aos desenvolvimentos ocorridos na cultura popular e na cultura de massas através dos média. No entanto, trata-se de um produto de entretenimento que continua a ser essencialmente dirigido ao público de fãs dos anos 80, daí verificar-se determinadas particularidades na evolução das suas estórias.

A economia global da saúde reflete o forte investimento em investigação e desenvolvimento (I&D) que tem sido realizado nos países desenvolvidos. No entanto, trata‑se de uma realidade que não se reflete nos países em desenvolvimento, os países do Sul sociológico. Estes países inclusivamente debatem‑se com outro tipo de problemáticas na área da saúde. Este artigo mostra uma panorâmica das lógicas dominantes na economia da saúde, à escala global, evidenciando as discrepâncias que se estão a originar em indicadores de referência. As considerações finais apontam como determinantes, para a correção das assimetrias, o nível de exequibilidade e de efetividade que os movimentos sociais que atuam neste campo possam vir a obter para o desenvolvimento de uma biopolítica democrática que corresponda às necessidades de todos.

Este artigo procura estabelecer os fundamentos filosóficos e epistemológicos que permitam suportar a educação para a cidadania, tendo em vista um novo conceito de cidadania que responda às necessidades da sociedade contemporânea. Neste âmbito, o artigo confronta autores clássicos com o intuito de indagar acerca dos limites e da natureza do conhecimento e da ação humana. A obra destes autores será relacionada com o trabalho de investigadores recentes, na área da epistemologia experimental e da psicologia. Isto permitirá tirar as conclusões desejadas, não perdendo de vista as caraterísticas e os desafios da sociedade contemporânea.

O objetivo deste estudo foi descrever as condições sanitárias relacionadas à moradia em uma comunidade rural do Vale do Jiquiriçá (BA). Trata-se de um estudo descritivo, quantitativo e de corte transversal. Os dados empíricos foram oriundos do sistema de informação em saúde e-SUS, referentes ao ano de 2017, sendo analisados de acordo com a epidemiologia descritiva com o auxílio do Microsoft Excel. Os resultados destacaram disparidades sanitárias da população rural estudada, deficiência na forma de esgotamento sanitário, destino do lixo e acesso aos domicílios. São necessários o planejamento e a elaboração da agenda de saúde local, de modo a contribuir para a qualidade de vida e de saúde da população do campo.

We present the performance of a Micro-Hole and Strip Plate (MHSP) electron multiplier in argon-xenon mixtures, at pressures of 1-7 bar. This microstructure can operate at high pressures without significant reduction of the maximum achievable gain. Absolute gains of 1-4 Â 10 3 were reached in Ar/50 mbar Xe over this pressure range; the maximum gain is imposed by the discharge limit, dropping at higher pressures. Energy resolutions between 14% and 16% were reached for 6 keV X-rays; they do not degrade significantly with increasing pressure. Better performances are expected by improved manufacturing of the MHSP. r 2004 Published by Elsevier B.V.