RESUMEN
The widely used plasticizer bisphenol-A (BPA) is well-known for producing neurodegeneration and cognitive disorders, following acute and long-term exposure. Although some of the BPA actions involved in these effects have been unraveled, they are still incompletely known. Basal forebrain cholinergic neurons (BFCN) regulate memory and learning processes and their selective loss, as observed in Alzheimer's disease and other neurodegenerative diseases, leads to cognitive decline. In order to study the BPA neurotoxic effects on BFCN and the mechanisms through which they are induced, 60-day old Wistar rats were used, and a neuroblastoma cholinergic cell line from the basal forebrain (SN56) was used as a basal forebrain cholinergic neuron model. Acute treatment of rats with BPA (40 µg/kg) induced a more pronounced basal forebrain cholinergic neuronal loss. Exposure to BPA, following 1- or 14-days, produced postsynaptic-density-protein-95 (PSD95), synaptophysin, spinophilin, and N-methyl-D-aspartate-receptor-subunit-1 (NMDAR1) synaptic proteins downregulation, an increase in glutamate content through an increase in glutaminase activity, a downregulation in the vesicular-glutamate-transporter-2 (VGLUT2) and in the WNT/ß-Catenin pathway, and cell death in SN56 cells. These toxic effects observed in SN56 cells were mediated by overexpression of histone-deacetylase-2 (HDAC2). These results may help to explain the synaptic plasticity, cognitive dysfunction, and neurodegeneration induced by the plasticizer BPA, which could contribute to their prevention.
RESUMEN
It is a fact that in recent years requests have greatly increased to obtain estimates of the legal age of undocumented individuals alleged to be minors who have been forced to enter different European Community countries for socioeconomic reasons or due to war. Spain is one of the countries most affected by this illegal immigration because of its proximity to North Africa. Therefore, it has become necessary to develop new standards which help provide a response to the demands of the justice administration. In recent years, the Superior Justice Court has rejected several pieces of expert evidence on the grounds that the age intervals therein were not sufficiently reliable and that the radiographic techniques used to determine age were invasive, potentially causing harm to the alleged minor. These sentences have caused interest in this field of work to increase within the scientific community. As a result, in order to improve age predictions and, above all, reduce minors' exposure to radiation, this study was created for completion on the Spanish population, using the ultrasound scan as a diagnostic technique. Used as a study sample were the ultrasound images of the proximal sternal epiphysis of the clavicle among 221 individuals of both sexes, of ages ranging from 5 to 30 years. All of the images were classified into 4 stages of fusion, in accordance with the development of metaphyseal closure proposed by Schulz et al. in 2008. The results show differences among the 4 proposed groups for each of the stages of fusion, with the results found in Stage II being especially important because, for both sexes, they would imply that the patient studied has reached an age of over 18 years, which is the legal age of adulthood in Spain, as established by the Spanish Constitution of 1978. Though further research is still recommended, these results, coupled with the use of ultrasound as a non-invasive diagnostic technique, could help solve some of the problems currently arising in justice courts.
