RESUMEN
Neuronal loss is the ultimate pathophysiologic event in central nervous system (CNS) diseases and replacing these neurons is one of the most significant challenges in regenerative medicine. Providing a suitable microenvironment for new neuron engraftment, proliferation, and synapse formation is a primary goal for 3D bioprinting. Among the various biomaterials, gelatin methacrylate (GelMA) stands out due to its Arg-Gly-Asp (RGD) domains, which assure its biocompatibility and degradation under physiological conditions. This work aimed to produce different GelMA-based bioink compositions, verify their mechanical and biological properties, and evaluate their ability to support neurogenesis. We evaluated four different GelMA-based bioink compositions; however, when it came to their biological properties, incorporating extracellular matrix components, such as GeltrexTM, was essential to ensure human neuroprogenitor cell viability. Finally, GeltrexTM: 8% GelMA (1:1) bioink efficiently maintained human neuroprogenitor cell stemness and supported neuronal differentiation. Interestingly, this bioink composition provides a suitable environment for murine astrocytes to de-differentiate into neural stem cells and give rise to MAP2-positive cells.
RESUMEN
Legality in the Global South suffers from problems of application by convenience. Some rules are applied, and some are not, depending on certain actors, such as the State, the stakeholders, or others. This undermines legitimation as constructed by legality and due process. These problems are connected to a wider complex formed by coloniality, internal colonialism, and a form of functional differentiation that limits autonomy of the different social systems. This complex of structural properties allows States and other actors to systematically use one system against the other or-within a given system-one level of rules against the other. This was the case in Ecuador: in the initial months of quarantine due to Covid-19, the government took decisions about external state bonds following international legislation-and quite contrary ones related to local work contracts. Once again, legality followed different paths in diverse cases. Ecuadorian economic authorities accept and respect conditions on external public bonds which are protected by some complex and specific clauses to secure the payment. The same authorities have different practices towards international and national legislation that were organized in the sense of legal subsidiarity. This text will explore reasons and effects of legal de-differentiation in the Global South in times of crisis. The Ecuadorian case in time of Covid-19 helps to understand how structural problems related to the lack of autonomy of the legal system are perpetuated and lead to effects of convenient political action.
RESUMEN
Este artículo presenta evidencias empíricas y elementos conceptuales para construir la noción de "gaycidad", entendida como una experiencia social distinguible de la experiencia social homosexual. La hipótesis principal sostiene que la gaycidad es heredera de procesos de des-diferenciación social que posibilitan procesos diferenciadores al interior del mundo gay. Si bien está referida a la ciudad argentina de Buenos Aires, aporta reflexiones tendientes a la comparación con otros grandes centros metropolitanos de la región latinoamericana.
Este artigo apresenta evidências empíricas e elementos conceituais para construir a noção de "gaycidade", entendida como uma experiência social distinta da experiência social homossexual. A hipótese principal sustenta que a "gaycidade" é herdeira de processos de desdiferenciação social que possibilitam processos diferenciadores no interior do mundo gay. Embora esteja referida à cidade argentina de Buenos Aires, contribui com reflexões que tendem à comparação com outros grandes centros metropolitanos da região latino-americana.
This article presents empirical evidence and conceptual elements to develop a notion of 'gayness,' understood as a social experience distinct from the 'homosexual' one. The main hypothesis holds that gayness is heir to de-differentiation processes that, in turn, enable differentiating processes within the gay world. Although referred to the city of Buenos Aires, in Argentina, this reflection is aimed at comparing the case to other large metropolitan centers in Latin America.