Sonic hedgehog signaling regulates mode of cell division of early cerebral cortex progenitors and increases

The morphogen Sonic Hedgehog (SHH) plays a critical role in the development of different tissues. In the central nervous system, SHH is well known to contribute to the patterning of the spinal cord and separation of the brain hemispheres. In addition, it has recently been shown that SHH signaling also contributes to the patterning of the telencephalon and establishment of adult neurogenic niches. In this work, we investigated whether SHH signaling influences the behavior of neural progenitors isolated from the dorsal telencephalon, which generate excitatory neurons and macroglial cells in vitro. We observed that SHH increases proliferation of cortical progenitors and generation of astrocytes, whereas blocking SHH signaling with cyclopamine has opposite effects. In both cases, generation of neurons did not seem to be affected. However, cell survival was broadly affected by blockade of SHH signaling. SHH effects were related to three different cell phenomena: mode of cell division, cell cycle length and cell growth. Together, our data in vitro demonstrate that SHH signaling controls cell behaviors that are important for proliferation of cerebral cortex progenitors, as well as differentiation and survival of neurons and astroglial cells.

O circuito espacial da produção petrolífera no rio Grande do Norte

Our study refers to the state of Rio Grande do Norte against the deployment of oil activity in their territory. In this sense the aim of this work was to analyze the presence of the loop space of the oil production system linked to objects and actions on the Rio Grande do Norte territory. From the so-called "oil shock", an event that caused global developments in several countries, Petróleo Brasileiro S/A (PETROBRAS) increased investments in drilling geological basins in Brazil. In the year 1973 was drilled in the sea area well which led to commercial production of oil and gas in Rio Grande do Norte. From that point on were added in some parts of the Potiguar territory, large systems of coupled objects to actions caused by several agents. In this context, geographic situations have been reorganized due to an unprecedented space circuit production accompanied by a new circle of cooperation. In the state happen all instances of the circuit: the production, distribution and consumption. In light of the theory of the geographical area seek to direct our thoughts to the operation of these bodies, and they are linked to material and immaterial flows multiscales. This perspective allows us to think the territory of Rio Grande do Norte entered into a new territorial division of labor characterized by specialization regional production. Oil activity was implemented in the territory of Rio Grande do Norte at a time marked by productive restructuring of various economic sectors. The oil sector has been acting increasingly linked the scientific and informational, with a view to increasing productivity. The presence of this circuit demanded the territory, specifically the Mossoró, an organizational structure that is different from the vast system nationally integrated private commercial corporations to small corporations, all of them relating directly or indirectly to PETROBRAS. The flows between companies whose headquarters are located in distant states and even countries have generated a continuous movement of goods, people, information and ideas, which is also causing new materialities in the territory