Measurement of glycogen synthase activity in crude extracts by CE

Glycogen synthase catalyzes the incorporation of UDP-glucose into glycogen. The activity of the enzyme is usually measured either by a spectrophotometric method or by a radioassay. The first one is not suitable because of the difficulties regarding the use of coupled enzymes in crude extracts, while the second is a time-consuming method involving glycogen isolation and manipulation of radioactivity. We have used a CZE technique as a novel approach to measure glycogen synthase activity. The separations were performed at 22 kV (36 mA) in uncoated capillaries (53 cm650 mm). Sample injection time was 30 s and nucleotides were monitored at 254 nm. Best resolution was achieved in 20 mM tetraborate buffer, pH 9.2. Curves of absorbance as a function of UDP and UDP-glucose concentration were linear. Enzyme activity in oocyte extracts was linear with respect to time (up to15 min) and enzyme concentration. The Km app. for UDP-glucose was 0.87 mM, a value identical to the one reported using the radioassay. CZE enables easy quantitation of compounds, high sensitivity, and automation of the process. Small sample sizes are required, interferences by auxiliary enzymes and manipulation of radioactivity are avoided, and analysis time is significantly diminished.This work was supported by the Fondo Nacional de Ciencia y Tecnología (Fondecyt), Chile, Project 1040886. We thank Dr. Lorena García and Ariel Díaz for valuable technical assistance, and Dr. Eduardo Kessi for helpful discussions

INTIMA-MEDIA THICKNESS IN OBESE ADOLESCENTS AND THEIR RELATION WITH METABOLIC SYNDROME

Artículo de publicación ISIIntroduction: Obese adolescents have higher cardiovascular risk (CVR). Intima-media thickness (IMT) detects early arterial vascular compromise. Objective: To evaluate whether obese adolescents have higher vascular compromise measured by IMT than non-obese adolescents, and if this is greater in those with metabolic syndrome (MS). Method: The study group (SG), obese children (BMI/age > p95), with and without MS and control group (CG), non-obese (BMI/age p10-85) and non nutritional or endocrine disease. We measured serum lipids, oral glucose tolerance test with insulin and carotid artery ultrasound. To evaluate the differences between test groups we used parametric and nonparametric statistics. Results: We evaluated 45 obese adolescents (20 women), 19 with MS, age 13 (9-16) years and 18 controls (14 women), aged 13(11-16) years. IMT of carotid bulb and internal carotid artery (ICA) were significantly higher in SG than CG (0.54 vs. 0.34, 0.34 vs. 0.25, p < 0.05). There was no difference between obese groups. IMT of ICA and bulb correlated positively with BMIz (r = 0.3 and 0.6, p < 0.05) and with waist circumference (CC) (r = 0.3 and 0.55, p < 0, 05). IMT of ICA was positively correlated with fasting insulin, HOMA and systolic blood pressure. In multivariate analysis only BMI and CC were associated independently to IMT. Conclusion: Obesity is an early risk factor for cardiovascular damage measured by IMT and IMT of ICA demonstrated a higher correlation with cardiovascular risk factors

Evaluación de los procesos cognitivos y afectivos en trabajadores de la construcción que nivelan sus estudios

Tesis (Psicopedagogo, Licenciado en Educación)Este Seminario de Grado nace con el objeto de poder optar al título de Psicopedagogo y Licenciado en Educación, para lo cual fue necesario buscar un tema interesante para investigar y que fuera un aporte tanto para la psicopedagogía como para la sociedad. La psicopedagogía permite estudiar al individuo y su entorno en las distintas etapas de aprendizaje que abarca su vida. A través de sus métodos propios se estudiarán las potencialidades cognoscitivas, afectivas y sociales para un mejor y sano desenvolvimiento en las actividades que desempeña un sujeto determinado. La presente investigación se basa en la evaluación de los procesos cognitivos y afectivos, en trabajadores de la construcción que no terminaron su escolaridad obligatoria y que hoy tienen la oportunidad de finalizar sus estudios a través del Programa de Nivelación de Estudios de la Corporación Educacional de la Construcción (COREDUC). La evaluación anteriormente señalada se llevará acabo en uno de los establecimientos educacionales de la COREDUC, donde los trabajadores se encuentran actualmente nivelando sus estudios

The Lost Community?

Chile has achieved a dramatic reduction in material poverty since 1990, in part through a massive programme of state-subsidized housing that has almost eliminated slums, especially in Santiago. Sceptics assert that the improvement in material conditions has been accompanied by a decline in the cohesion and quality of 'community' in poor neighbourhoods. This article challenges this assertion, using data from a 1985 survey conducted in "poblaciones" (i.e. public housing dating from the 1960s) and a 2001 survey conducted in newly built public housing or "villa"s. In contrast to popular wisdom, these surveys suggest that "villas" score higher than "poblaciones" in most indicators of social capital analyzed. Finally, this article contends that in order to comprehend the relation between poverty, space and community, more networked and decentred analytical approaches are needed. Copyright (c) 2009 The Author. Journal Compilation (c) 2009 Joint Editors and Blackwell Publishing Ltd.