Chronic consumption of sweeteners increases carbonylated protein production in lymphocytes from mouse lymphoid organs

Artículo derivado de un proyecto de investigación para evaluar el efecto del consumo de edulcorantes sobre el sistema inmunitarioBackground: The prevalence of overweight, obesity and diabetes mellitus has increased in Mexico, therefore, sucralose and stevia are being used as alternative non-caloric sweeteners to reduce energy intake. Moreover, poorly balanced diets can lead to the formation of carbonyl groups, a marker used to determine oxidative damage to proteins. Increased presence of carbonylated proteins in CD1 mice chronically consuming sweeteners, may point them as causing oxidative damage. Aims: To determine whether the continued use of natural and artificial sweeteners increases the presence of carbonylated proteins in lymphocytes of lymphoid tissues in CD1 male mice. Methods: The present study was conducted with 72 CD1 newly weaned (21-day old) male mice, fed with standard lab diet and water ad libitum; mice were hosted in cages in groups of 4 under controlled temperature conditions (19-21°C), and light/dark cycles of 12/12 h. Weight and food intake was quantified weekly. Three groups of mice were randomly conformed: a) Baseline (21-day old, newly weaned, n=8); b) 6-week of treatment (63-day old, n=32); c) 12-week of treatment (105-day old, n=32). Groups b and c were divided into 4 subgroups each (n=8): i) Control (CL) without sweeteners; ii) Sucrose (SUC); iii) Sucralose (SUCL), and iv) Stevia (ST). Body weight, food, and water consumption were measured, and BMI was calculated from those values. Lymphocytes from Peyer's patches, peripheral blood and spleen were isolated, and from these cells carbonylated protein concentration was quantified. Blood glucose was also assessed. Results: Mice in SUCL and ST groups had lower weight gain and BMI compared to those that consumed SUC. The SUCL group consumed more food and the ST group decreased food intake, as compared with SUC and control groups. ST group drank more sweetened water, compared to the other groups. The percentage of blood lymphocytes and the carbonylated proteins concentrations were higher in the SUCL group. Conclusions: The chronic consumption of sucralose, caused an increase in food intake. In addition, the percentage of lymphocytes circulating in blood was elevated, as well as the concentration of carbonylated proteins in these cells

Implementación del sistema de gestión de seguridad y salud en el trabajo en la ciudad de Cartagena

En la ciudad de Cartagena de indias todas las empresas que realicen alguna actividad económica tienen la obligación de ejecutar acciones para garantizar la seguridad y la salud de sus trabajadores en los lugares de trabajo. Algunas empresas hacen caso omiso al evento de que sus colaboradores están expuestos a muchos tipos de riesgos sin importar la labor que desempeñen y en el momento en el que los riesgos intrínsecos en las actividades que se llevan a cabo a diario se materializan y afectan de una forma u otra a los trabajadores, sus efectos no solo perjudican al trabajador, sino también a la organización y a su entorno social y familiar. En este ensayo se realizo una revisión de los principales resultados y cambios más relevantes que ha tenido la salud ocupacional en Cartagena, para identificar cuáles son las causas de la inadecuada implementación del sistema de gestión de seguridad y salud en el trabajo (SGSST)In the city of Cartagena de Indias, all companies that carry out any economic activity have the obligation to carry out actions to guarantee the safety and health of their workers in the workplace. Some companies ignore the event that their collaborators are affected by many types of risks regardless of the workforce they perform and at the moment when the risks inherent in the activities carried out in a newspaper materialize and affect in one way or another to workers, its effects not only harm the worker, but also the organization and its social and family environment. In this essay, a review of the main results and most relevant changes that occupational health has had in Cartagena was made, to identify the problems that are the causes of the inadequate implementation of the occupational health and safety management system (SGSST)

The whole-brain pattern of magnetic susceptibility perturbations in Parkinson's disease

Although iron-mediated oxidative stress has been proposed as a potential pathomechanism in Parkinson's disease, the global distribution of iron accumulation in Parkinson's disease has not yet been elucidated. This study used a new magnetic resonance imaging contrast, quantitative susceptibility mapping, and state-of-the-art methods to map for the first time the whole-brain landscape of magnetostatic alterations as a surrogate for iron level changes in n = 25 patients with idiopathic Parkinson's disease versus n = 50 matched controls. In addition to whole-brain analysis, a regional study including sub-segmentation of the substantia nigra into dorsal and ventral regions and qualitative assessment of susceptibility maps in single subjects were also performed. The most remarkable basal ganglia effect was an apparent magnetic susceptibility increase-consistent with iron deposition-in the dorsal substantia nigra, though an effect was also observed in ventral regions. Increased bulk susceptibility, additionally, was detected in rostral pontine areas and in a cortical pattern tightly concordant with known Parkinson's disease distributions of α-synuclein pathology. In contrast, the normally iron-rich cerebellar dentate nucleus returned a susceptibility reduction suggesting decreased iron content. These results are in agreement with previous post-mortem studies in which iron content was evaluated in specific regions of interest; however, extensive neocortical and cerebellar changes constitute a far more complex pattern of iron dysregulation than was anticipated. Such findings also stand in stark contrast to the lack of statistically significant group change using conventional magnetic resonance imaging methods namely voxel-based morphometry, cortical thickness analysis, subcortical volumetry and tract-based diffusion tensor analysis; confirming the potential of whole-brain quantitative susceptibility mapping as an in vivo biomarker in Parkinson's disease

Relationship between prolonged sweetener consumption and chronic stress in the production of carbonylated proteins in blood lymphocytes

Artículo derivado de un proyecto de investigación para la identificación del efecto del consumo de edulcorantes sobre el sistema inmunitario.Introduction: Modern lifestyles have changed eating habits, encouraged physical inactivity, and increased stress in daily life. These living conditions cause elevated concentrations of carbonylated proteins like biomarker of oxidative stress. The expression of this proteins represent irreversible damage to structural intracellular proteins in cells and extracellular matrix. It is not clear whether a rise in the concentration of these proteins is the origin or consequence of diseases. Objective: To determine in a healthy young mice model the possible correlation between prolonged sweetener consumption and the presence of chronic physiological stress, evidenced by the production of carbonylated proteins in peripheral blood lymphocytes. Methods: Sixty-four 21-day-old CD1 male mice were divided into two groups, stressed (with immobilization) and unstressed. Each group was divided into four subgroups: Control or experimental with a 6-week administration of sucrose, sucralose or stevia. Body mass index, food intake, number and concentration of carbonylated proteins, levels of glucose and peripheral lymphocytes in blood were evaluated. Data were analyzed with ANOVA. Results: Compared to the unstressed control, the glucose concentration was elevated in all stressed subgroups (F = 13.41, p < 0.01), with greater weight found in the stressed sucralose supplemented subgroup (F = 77.58, p < 0.001). The blood level of peripheral lymphocytes was above the control in all subgroups (F = 19.97, p < 0.01), except the decrease observed in unstressed sucrose supplemented subgroup. Carbonylated protein concentration in peripheral blood lymphocytes was high in all subgroups (versus the control) except in unstressed animals suppelemented with stevia (F = 51.16, p <0.01). Conclusions: Stress plus sucralose increased number of lymphocytes and carbonylated proteins concentration. The physiological stress with or without sweetener consumption generated increase in carbonylated proteins concentration. Stevia did not modify lymphocytes and carbonylated proteins

Methane fluxes from tropical coastal lagoons surrounded by mangroves, Yucatán, Mexico

Methane concentrations in the water column and emissions to the atmosphere were determined for three tropical coastal lagoons surrounded by mangrove forests on the Yucatán Peninsula, Mexico. Surface water dissolved methane was sampled at different seasons over a period of 2 years in areas representing a wide range of salinities and anthropogenic impacts. The highest surface water methane concentrations (up to 8378 nM) were measured in a polluted canal associated with Terminos Lagoon. In Chelem Lagoon, methane concentrations were typically lower, except in the polluted harbor area (1796 nM). In the relatively pristine Celestún Lagoon, surface water methane concentrations ranged from 41 to 2551 nM. Methane concentrations were negatively correlated with salinity in Celestún, while in Chelem and Terminos high methane concentrations were associated with areas of known pollution inputs, irrespective of salinity. The diffusive methane flux from surface lagoon water to the atmosphere ranged from 0.0023 to 15 mmol CH4 m-2 d-1. Flux chamber measurements revealed that direct methane release as ebullition was up to 3 orders of magnitude greater than measured diffusive flux. Coastal mangrove lagoons may therefore be an important natural source of methane to the atmosphere despite their relatively high salinity. Pollution inputs are likely to substantially enhance this flux. Additional statistically rigorous data collected globally are needed to better consider methane fluxes from mangrove-surrounded coastal areas in response to sea level changes and anthropogenic pollution in order to refine projections of future atmospheric methane budgets

Estrategias disposicionales y aprendizajes significativos en el aula virtual

Este estudio identificó las estrategias disposicionales empleadas por tutores en el diseño y la implementación de clases a nivel universitario, para promover aprendizajes significativos en un entorno virtual de aprendizaje en ocho diseños instruccionales analizados. Metodológicamente, se siguió el enfoque cualitativo-fenomenológico utilizando como instrumentos el análisis de contenido en cuatro aulas virtuales y entrevistas semiestructuradas efectuadas a una docente y a cinco estudiantes de Psicología en modalidad a distancia con apoyo del aula virtual de una institución universitaria. Se aplicaron cuatro tipos de matrices para el análisis de contenido, con las cuales se identificaron los aspectos motivacionales y los tipos de aprendizaje significativo que se presentan en los diseños instruccionales de los cursos analizados. Para validar el estudio se recurrió a un análisis de datos mediante el proceso de triangulación por instrumentos. Los resultados demostraron que (a) en algunos casos, se hace uso de estrategias disposicionales que promueven aprendizajes significativos con los contenidos discursivos de las actividades y de las retroalimentaciones mediante la comunicación sincrónica y asincrónica; (b) las estrategias que utiliza el cuerpo docente para motivar a sus estudiantes, no son el resultado de un diseño previo e intencionado sino de un proceso intuitivo; (c) las estrategias motivacionales que el profesorado emplea implican el uso de frases o imágenes que motivan a trabajar en los contenidos temáticos. Teniendo en cuenta los resultados del estudio, se recomienda para futuras investigaciones en el ámbito educativo sobre la modalidad a distancia, desarrollar e implementar procesos instruccionales previamente diseñados, donde el personal docente potencie tanto la comunicación efectiva como el proceso de aprendizaje, utilizando estrategias de enseñanza que promuevan la motivación al aprendizaje de modo intencional y pertinente para las dinámicas propias de las aulas virtuales, mostrando flexibilidad y adaptación a las necesidades del estudiantado

Predictors of hyperlipidemia during the first half of pregnancy in Mexican women

Objective: To determine the predictors of hypercholesterolemia and of hypertriglyceridemia during the first half of pregnancy in Mexican women. Methods: Cross-sectional comparative study of pregnant women with less than 21 weeks of gestational age. Measurements: Demographic information, obstetric history, prepregnancy body mass index, cholesterol and triglycerides. Cross tabulations and multiple logistic regression were used for statistical analysis. Results: 230 participants; 61 women with normal prepregnancy body mass index, 108 with overweight, and 61 with obesity. Dyslipidemia was defined as elevated cholesterol (>180 mg/dL) or triglycerides (>170 mg/dL). After adjusting by potential confounders, independent predictors of hypercholesterolemia included being overweight (OR=2.8, 95% CI 1.4-5.9), being obese (OR=3.7 95% CI 1.6-8.4) or being on the second trimester of pregnancy. The same predictors were found for hypertriglyceridemia, respectively OR=2.8, 95% CI 1.4-5.6, OR=2.9, 95% CI 1.3-6.5, OR=2.6, 95% CI 1.4-4.7. Conclusion: Mexican women with prepregnancy overweight or obesity have greater risk of suffering hypercholesterolemia and hypertriglyceridemia during pregnancy. Women in the second trimester had higher levels of both lipids as compared to the first one. This is the first Mexican study that confirms the increase of lipids as gestational age progresses

Complete IRAC mapping of the CFHTLS-DEEP, MUSYC AND NMBS-II FIELDS

The IRAC mapping of the NMBS-II fields program is an imaging survey at 3.6 and 4.5$\mu$m with the Spitzer Infrared Array Camera (IRAC). The observations cover three Canada-France-Hawaii Telescope Legacy Survey Deep (CFHTLS-D) fields, including one also imaged by AEGIS, and two MUSYC fields. These are then combined with archival data from all previous programs into deep mosaics. The resulting imaging covers a combined area of about 3 $deg^2$, with at least $\sim$2 hr integration time for each field. In this work, we present our data reduction techniques and document the resulting coverage maps at 3.6 and 4.5$\mu$m. All of the images are W-registered to the reference image, which is either the z-band stack image of the 25\% best seeing images from the CFHTLS-D for CFHTLS-D1, CFHTLS-D3, and CFHTLS-D4, or the K-band images obtained at the Blanco 4-m telescope at CTIO for MUSYC1030 and MUSYC1255. We make all images and coverage maps described herein publicly available via the Spitzer Science Center.Comment: Accepted in PASP; released IRAC mosaics available upon publication of the pape

Evaluación productiva y económica de regímenes de intermitencia en el sistema de solución nutritiva recirculante en el cultivo de lechuga (Lactuca sativa L. var. capitata).

Resumen (Spanish, English)78 p.Durante los meses de Octubre y Noviembre de 1995, se realizó un ensayo en la Estación Experimental de Panguilemo, de la Universidad de Talca, ubicada en la región del Maule, comuna de Talca (35º26´LS; 71º41´, 90 m.s.n.m.), destinado a evaluar económica y productivamente los efectos de cuatro regímenes de circulación de solución nutritiva, con un tratamiento control de circulación continua, con un tiempo de funcionamiento de 24 horas y tres tratamientos con regímenes de intermitencia con tiempos de circulación de 15,5; 12 y 10 horas, en el sistema de solución nutritiva recirculante (NFT) en el cultivo de Lactuca sativa var. Capitata cv. Queen Crown de primavera - verano bajo invernadero. En relación a la productividad se obtuvo que el tratamiento con circulación continua presentó el mayor rendimiento en materia fresca (432 g/planta). La calidad de las cabezas de lechuga fue afectada por la incidencia de tipburn en todos los tratamientos. Sin embargo el tratamiento control y el tratamiento de 15,5 horas de funcionamiento, obtuvieron la mayor aceptación general evaluada a través de un panel sensorial. Respecto a la evaluación económica, los tratamientos intermitentes mejoraron la rentabilidad del sistema al disminuir los costos directos de producción, debido al menor consumo de energía eléctrica, agua y de solución nutritiva