http://hdl.handle.net/11336/116633 Eventos de INSTITUTO DE INV. MEDICAS MERCEDES Y MARTIN FERREYRA 2024-06-14T03:05:36Z http://hdl.handle.net/11336/237833 Catalytic activity of beta–galactosidase entrapped in a silicate matrix: Effect of the substrate type, porous structure and aging time Burgos, Martha Ines; Carrer, Dolores Catalina; Perillo, Maria Angelica Protein encapsulation in solid matrixes is of interest for biotechnological purposes and it also serves as a model of molecular crowding. We have successfully entrapped the enzyme β-galactosidase (β-gal) in silicate gels via a sol-gel reaction. The catalytic activity of encapsulated β-gal (Eβ-gal) was compared with the activity of the soluble form (Sβ-gal) with two different substrates (ONPG and PNPG) and at different aging times. Data were analyzed with a Michaellis-Menten model. With the substrate ONPG, we found a Vmax value higher for Eβ-gal than for Sβ-gal and this difference increased at longer aging times. On the contrary, with PNPG, Vmax was not affected neither by the enzyme condition (Sβ-gal and Eβ-gal) nor by the aging time. The porous structure of the silicate matrix was also studied as a function of aging time of the gels. Thus, fluorescence correlation spectroscopy (FCS) was applied through the analysis of diffusional properties of fluorescent probes of different sizes, entrapped in the gel matrix. We observed an anomalous diffusion in some conditions, suggesting a self-similar pore structure, and aging time dependent changes in diffusion coefficients. Taken together our result supports the hypothesis that there is a relationship between the catalytic mechanism proposed for β-gal and water availability in the silicate gel since the ratio between bulk and structured water depends on the pore size. 2013-01-01T00:00:00Z http://hdl.handle.net/11336/234448 Brain Awareness Week Córdoba: Brain and Perception Cotella, Evelin Mariel; Garcia Keller, Constanza; Langer, Federico; Laurino, Lisandro; Marcotti, Aída; Mestres, Iván; Mir, Franco Rafael; Montroull, Laura Ester; Pisano, María Victoria; Zamponi, Emiliano; Cambiasso, Maria Julia In March 2013 the Brain Awareness Week (BAW) was celebrated for the first time in Argentina. Three cities participated in the event. Our group of Young Neuroscience Researchers was in charge of hosting the BAW in Córdoba. Throughout the week we carried out an urban intervention under the title of "Brain and Perception". The activities were addressed to the general public and they were related to perception, attention and emotions. The format of the exhibition consisted of audiovisual stands where we exposed images and interactive games. The audience (estimated at approximately 2,500 people) played several games related with sensory illusions, and were guided through some of the main questions of contemporary neuroscience. Also, we handed out brochures with curiosities about the brain. After the official “Brain Awareness Week”, the exhibition continued over a month, associated with Cuatrociencia, the Science and Technology Fair from the National University of Cordoba. During this period, the BAW stand received approximately 120,000 visitors. In addition, we offered lectures about diverse neuroscience topics, as well as a photographic exhibition on neurons and the brain (“micro&Macro: Tu Mirada sobre las Neurociencias”). It was really gratifying for our group to interact with the people and to see how interested and amazed they were about the brain functions. We consider the activity a major success and we hope we can collaborate more often in this kind of initiatives. 2013-01-01T00:00:00Z http://hdl.handle.net/11336/215276 Impulsividad, normas sociales y expectativas hacia el alcohol: Su contribución en el consumo de alcohol en niños y adolescentes Caneto, Florencia; Pautassi, Ricardo Marcos; Pilatti, Angelina Introducción: El inicio temprano del consumo de alcohol se relaciona con una mayor probabilidad de presentar consumo excesivo de alcohol y mayor número de consecuencias negativas. Pocos estudios locales, sin embargo, estudian las conductas de consumo a edades tempranas. Conocer la ocurrencia de consumo de alcohol a estas edades y qué factores incrementan la vulnerabilidad a iniciar y escalar este consumo es de relevancia sanitaria para generar estrategias de prevención eficaces. Objetivo: Analizar el efecto de la edad, impulsividad, percepción del consumo de pares y padres y de las expectativas hacia el alcohol sobre el consumo de alcohol de niños y adolescentes de 10 a 15 años.Método: Muestra: 676 niños (10-12 años, M edad= 11.25±0.83; 52.7% mujeres; M gramos por ocasión de consumo= 7.5±14.89; M días consumo/año= 3.11±5.81) y 917 adolescentes (13-15 años, M edad= 13.55±0.65; 54.4% mujeres; M gramos por ocasión de consumo= 37.8±47.94; M días con consumo/año= 9.49±12.92) asistentes a escuelas públicas y privadas de Córdoba Capital. Procedimiento: Los alumnos completaron una encuesta para medir: -impulsividad (escala UPPS-P: Urgencia Negativa [UN] y Positiva [UP]; Falta de Premeditación [F-PREM]); Falta de Perseverancia [F-PERS] y Búsqueda de Sensaciones [BS]); -normas descriptivas del consumo (percepción de la frecuencia del consumo de padres [BS] y de la cantidad de alcohol que consumen los amigos y amigas [P-PARES]); -expectativas hacia el alcohol (EA). Se realizaron regresiones jerárquicas, separando la muestra en niños y adolescentes y mujeres y varones, para determinar la influencia de distintos factores en la cantidad de alcohol consumida por ocasión (CAC) y frecuencia usual de consumo (FREC). En el primer paso se incluyó la edad, en el segundo impulsividad, luego las normas descriptivas y, finalmente, las EA.Resultados: Niños/as: las variables explicaron el 53% y el 39% de la varianza de la CAC y el 29% y 25% de la FREC (niñas y niños, respectivamente). Entre las niñas, la edad, UP y P-PARES, especialmente de las amigas, se asociaron de manera positiva a una mayor CAC; mientras que F-PERS y P-PARES, especialmente de los amigos, explicaron una mayor FREC. Entre los niños, la percepción de un mayor consumo de alcohol de la madre y del grupo de pares, especialmente de las amigas, se asociaron a una mayor CAC; mientras que sólo la percepción de un mayor consumo de los amigos varones tuvo un efecto significativo sobre la FREC. Adolescentes: las variables incluidas en el modelo explicaron el 49% y el 50% de la varianza de la cantidad de consumo de alcohol y el 41% y 36% de la frecuencia de consumo de alcohol (mujeres y varones, respectivamente). Entre las mujeres, la edad, F-PREM, las EA positivas y negativas y P-PARES explicaron una mayor CAC; mientras que la edad, las EA negativas y P-PARES, especialmente de los amigos varones, explicaron una mayor FREC. Entre los varones, la percepción de un mayor consumo entre amigos varones, pero no de las amigas mujeres, y las EA positivas y negativas, explicaron una mayor CAC; mientras que la percepción de un mayor consumo de la madre y de los amigos varones, junto a un menor nivel de EA negativas, explicaron la mayor FREC.Discusión:Estos resultados muestran que los factores que incrementan la vulnerabilidad a consumir alcohol de manera temprana difieren en función del periodo del desarrollo y, además, son específicos de cada sexo. Más allá de la especificidad de cada modelo, un factor determinante en todos los casos refiere a la influencia del grupo de pares. Se enfatiza la utilidad de pensar estrategias preventivas generales que focalicen en esta variable y, además, que atiendan a las particulares de cada edad y sexo. 2018-01-01T00:00:00Z http://hdl.handle.net/11336/212740 Coping motives for drinking as a mediator between anxiety and depression, and alcohol outcomes in community Spanish young adults González Ponce, Bella; Vera, Belén del Valle; Pilatti, Angelina; Pautassi, Ricardo Marcos; Parrado González, Alberto; Dacosta Sánchez, Daniel; Fernández Calderón, Fermín Consistent with the medication hypothesis, drinking to cope with negative affect appears to mediate the relationship between mental health and alcohol-related problems, which has been shown in college students. However, there is a lack of evidence in non-university samples that limits the generalization of results. The present study examines the mediating role of coping motives in the relationship between depression and anxiety and alcohol outcomes (frequency and quantity of alcohol use, binge drinking, and alcohol-related consequences). Prospective design with a baseline assessment and a 2-month follow-up. We recruited 334 young adults in the community (mean = 21.1; SD = 2.21) who completed a questionnaire to measure coping motives for drinking and depression and anxiety (Brief Symptom Inventory) at baseline. Eight mediation models were tested, one for each alcohol outcome (at follow-up) for depression and another four for anxiety. The coping motives for drinking mediated the positive relationships between depression and alcohol outcomes, such that higher levels of depression were associated with higher coping motives, which in turn, were associated with higher alcohol-related outcomes. The same results were found for anxiety, except for the relationship between anxiety and binge drinking, which was not mediated by coping motives. Our findings are consistent with the medication hypothesis that "drinking to cope with negative affect" is a critical mediator of associations between mental health and alcohol-related problems in young adults in the community. Training in healthy coping strategies against negative affect should be useful for interventions aimed at reducing alcohol use and their harms. 2023-01-01T00:00:00Z