A process-specific approach in the study of normal aging deficits in cognitive control: What deteriorates with age?

Bearing in mind that cognitive control is a complex function that includes several processes, it is not clear exactly which ones deteriorate with age. In fact, controversial results have been found. For example, some studies indicate that age-related deficits are observed in proactive and not in reactive control, others show that it is reactive control that is impaired and not proactive control, and some studies find no deficits at all (e.g., Kopp, Lange, Howe, & Wessel, 2014; Xiang et al., 2016). One possible reason is that the contribution of different processes to the deterioration of cognitive control was investigated separately, i.e., without testing all processes within the same paradigm. Therefore, the main goal of the present experiment was to study the impact of normal aging on several processes related to cognitive control within the same task, which included both Simon and Spatial Stroop trials. The study focused on the following processes: generation of conflict measured by automatic response capture (i.e., stronger task-irrelevant information processing compared to task-relevant information processing); conflict detection; and control implementation (which can be reactive control, both within trials and across trials, and proactive control, as a task-set strategy). The results showed larger automatic response capture for older adults when facing a stimulus-response conflict (Simon) but not a stimulus-stimulus conflict (Spatial Stroop). Similarly, older adults also showed larger detection effects for both conflicts. However, regarding control implementation, they only showed difficulties in inhibiting the early automatic response capture (within-trial reactive control) but not reactive control across trials or proactive control. In conclusion, it seems that older adults are more affected by the presence of task-irrelevant information, especially when it comes to resolving stimulus-response conflict. However, they showed no impairments in their ability to implement cognitive control both across trials and as a task-set strategy

Maslinic Acid, a Natural Triterpene, Induces a Death Receptor-Mediated Apoptotic Mechanism in Caco-2 p53-Deficient Colon Adenocarcinoma Cells

Maslinic acid (MA) is a natural triterpene present in high concentrations in the waxy skin of olives. We have previously reported that MA induces apoptotic cell death via the mitochondrial apoptotic pathway in HT29 colon cancer cells. Here, we show that MA induces apoptosis in Caco-2 colon cancer cells via the extrinsic apoptotic pathway in a dose-dependent manner. MA triggered a series of effects associated with apoptosis, including the cleavage of caspases -8 and -3, and increased the levels of t-Bid within a few hours of its addition to the culture medium. MA had no effect on the expression of the Bax protein, release of cytochrome-c or on the mitochondrial membrane potential. This suggests that MA triggered the extrinsic apoptotic pathway in this cell type, as opposed to the intrinsic pathway found in the HT29 colon-cancer cell line. Our results suggest that the apoptotic mechanism induced in Caco-2 may be different from that found in HT29 colon-cancer cells, and that in Caco-2 cells MA seems to work independently of p53. Natural antitumoral agents capable of activating both the extrinsic and intrinsic apoptotic pathways could be of great use in treating colon-cancer of whatever origin.This study was supported by grants Group BIO 157 from the Technology and Innovation Council of the Andalucian regional government and AGL2006-12210-C03-02/ALI, SAF2005-01627, ISCIII-RTICC (RD06/0020/0046) from the Spanish government and European Union FEDER funds

High glycine concentration increases collagen synthesis by articular chondrocytes in vitro: acute glycine deficiency could be an important cause of osteoarthritis

Collagen synthesis is severely diminished in osteoarthritis; thus, enhancing it may help the regeneration of cartilage. This requires large amounts of glycine, proline and lysine. Previous works of our group have shown that glycine is an essential amino acid, which must be present in the diet in large amounts to satisfy the demands for collagen synthesis. Other authors have shown that proline is conditionally essential. In this work we studied the effect of these amino acids on type II collagen synthesis. Bovine articular chondrocytes were cultured under a wide range of different concentrations of glycine, proline and lysine. Chondrocytes were characterized by type II collagen immunocytochemistry of confluence monolayer cultures. Cell growth and viability were assayed by trypan blue dye exclusion method. Type II collagen was measured in the monolayer, every 48 h for 15 days by ELISA. Increase in concentrations of proline and lysine in the culture medium enhances the synthesis of type II collagen at low concentrations, but these effects decay before 1.0 mM. Increase of glycine as of 1.0 mM exceeds these effects and this increase continues more persistently by 60–75%. Since the large effects produced by proline and lysine are within the physiological range, while the effect of glycine corresponds to a much higher range, these results demonstrated a severe glycine deficiency for collagen synthesis. Thus, increasing glycine in the diet may well be a strategy for helping cartilage regeneration by enhancing collagen synthesis, which could contribute to the treatment and prevention of osteoarthriti

Mobilidade, acidentes de trânsito e fatores associados entre estudantes universitários da Guatemala

El objetivo fue identificar y cuantificar la asociación entre la intensidad de exposición (km/año recorridos), la accidentalidad y sus factores asociados en universitarios de Guatemala. Se realizó un estudio trasversal durante el curso 2010-2011, sobre una muestra de 1.016 conductores, quienes cumplimentaron un cuestionario autoadministrado que valoraba: patrones de movilidad, uso de dispositivos de seguridad, estilos de conducción y accidentalidad. Se obtuvieron asociaciones positivas entre la intensidad de exposición y la mayor implicación en circunstancias de riesgo al volante (coeficiente de regresión ajustado de 3,25, IC95%: 2,23-4,27, para las mayores exposiciones). Tanto una mayor implicación en tales circunstancias, como una mayor edad, fueron las variables más fuertemente asociadas con la mayor accidentalidad. Pese a que la intensidad de exposición se asocia positivamente con una mayor accidentalidad, se constató que la mayor parte de dicha asociación está mediada por una mayor implicación en circunstancias de riesgo al volante.The aim of this study was to identify and quantify the association between the amount of driving (km/year), traffic accidents, and other factors among university students in Guatemala. A cross-sectional study was performed during the 2010-2011 school year in a sample of 1,016 drivers who completed a self-administered questionnaire that assessed mobility patterns, use of safety accessories, driving style, and automobile crashes. The results showed a positive association between amount of driving and greater involvement in risky driving (adjusted regression coefficient 3.25, 95%CI: 2.23-4.27, for the highest level of exposure). More frequent involvement in risky driving and older age showed the strongest associations with traffic accidents. Although the amount of driving was positively associated with a higher accident rate, most of this association was found to be mediated by involvement in risky driving practices.O objetivo foi identificar e quantificar a associação entre a intensidade de exposição (km/anos percorridos), a acidentalidade e os seus fatores em universitários da Guatemala. Realizou-se um estudo transversal durante o curso 2010-2011 sobre uma amostra de 1.016 condutores de veículos, que responderam a um questionário autoadministrado que valorizava: padrões de mobilidade, uso de dispositivos de segurança, maneira de condução e acidentalidade. Obtiveram-se associações positivas entre intensidade de exposição e maior implicância em circunstâncias de risco ao conduzir (coeficiente de regressão ajustado a 3,25; IC95%: 2,23-4,27, para as maiores exposições). Tanto a maior implicância em ditas circunstâncias como uma maioridade foram as variáveis mais fortemente associadas com a maior acidentalidade. Apesar de a intensidade de exposição ser associada positivamente com uma maior acidentalidade, estabelecemos que a maior parte da dita associação está mediada pela maior implicância em circunstâncias de risco ao conduzir

Estética y educación matemática

Al igual que los aspectos cognitivos y afectivos, los factores estéticos, entendidos estos como aquellas características de las Matemáticas escolares que de alguna manera atraen a los alumnos, influyen en la enseñanza y el aprendizaje de las Matemáticas. Este trabajo presenta los resultados de un cuestionario exploratorio circunscrito en un trabajo de investigación que tiene como objetivo conocer los aspectos de las Matemáticas escolares que resultan estéticos para los escolares de Secundaria Obligatoria. Los resultados obtenidos ponen de manifiesto que algunos alumnos son capaces de percibir cualidades estéticas en diversos aspectos de las Matemáticas

Are Ancestral Medical Practices the Future Solution to Today’s Medical Problems?

Our cells and organs are threatened and, in most cases, constantly subjected to the aggression of numerous situations, both endogenous, characterized by unfavorable genetics, and exogenous, by deficient or inadequate nutrition, and even by a hostile environment; in most cases, they ultimately cause a cascade of degenerative and cardiovascular diseases, cancer, and infections, as well as those related to the metabolic syndrome, all of which eventually generate irreversible damage to the organism and, consequently, a significant deterioration in its survival [...

Data for Social and non-social categorisation in investment decisions and learning

Data for Social and non-social categorisation in investment decisions and learnin