Utilización de un método in vitro para evaluar la toxicidad de chaya, una planta nutritiva utilizada en medicina tradicional para la disminución del colesterol.

La “chaya” (Cnidoscolus chayamansa y Cnidoscolus aconitifolius) pertenece a la familia de las Euphorbiacea, es conocida como árbol de espinaca y ha sido cultivada desde la época prehispánica, se usaba como hasta hoy como planta comestible, medicinal y ornamental por más de 10 grupos Mayas y también por otros grupos Mexicanos y Mesoamericanos. Normalmente se encuentra cultivada en huertos familiares o jardines, la hoja algunas veces el pecíolo y los brotes son cosechadas y cocidas para varios tipos de guisados siendo una fuente importante de proteínas, beta caroteno, vitaminas, ácido ascórbico, calcio y hierro o son utilizadas con fines medicinales destacando su propiedad como hipocolesterolémico. El propósito del presente trabajo fue la evaluación preliminar de la toxicidad de tres extractos obtenidos de las hojas de C. chayamansa en un modelo in vitro, utilizando Artemia salina

Índice de saponificación de cinco mantecas determinado mendiante un micrométodo

Las mantecas son triglicéridos sólidos a temperatura ambiente con un notable valor nutritivo por su alto valor calórico y son ampliamente usadas en el procesado de los alimentos. Su calidad puede sufrir deterioros durante el proceso de preparación o en el almacenamiento, por lo que se han establecido parámetros analíticos como el Índice de saponificación para el monitoreo de la calidad. En esta investigación se determinó el Índice de saponificación (IS) de cinco mantecas mediante el empleo de un micrométodo, basado en la Norma Mexicana NMX-F-174-S-1981, para indagar si cumplen con este parámetro de calidad. Las muestras analizadas exhibieron valores que se ubicaron dentro de los rangos de normatividad establecidos en la legislación. La técnica aplicada es una adaptación a nivel microescala y presenta diferencias con la técnica oficial, que le proporcionan una mayor exactitud. Este estudio resalta la importancia de incorporar micrométodos en el diseño de las normas oficiales de análisis dado sus ventajas como rapidez, precisión, exactitud, bajo costo y ser amigable con el medio ambiente

Cardiovascular disease, chronic kidney disease, and diabetes mortality burden of cardiometabolic risk factors from 1980 to 2010: a comparative risk assessment

Background High blood pressure, blood glucose, serum cholesterol, and BMI are risk factors for cardiovascular diseases and some of these factors also increase the risk of chronic kidney disease and diabetes. We estimated mortality from cardiovascular diseases, chronic kidney disease, and diabetes that was attributable to these four cardiometabolic risk factors for all countries and regions from 1980 to 2010. Methods We used data for exposure to risk factors by country, age group, and sex from pooled analyses of populationbased health surveys. We obtained relative risks for the eff ects of risk factors on cause-specifi c mortality from metaanalyses of large prospective studies. We calculated the population attributable fractions for- each risk factor alone, and for the combination of all risk factors, accounting for multicausality and for mediation of the eff ects of BMI by the other three risks. We calculated attributable deaths by multiplying the cause-specifi c population attributable fractions by the number of disease-specifi c deaths. We obtained cause-specifi c mortality from the Global Burden of Diseases, Injuries, and Risk Factors 2010 Study. We propagated the uncertainties of all the inputs to the fi nal estimates. Findings In 2010, high blood pressure was the leading risk factor for deaths due to cardiovascular diseases, chronic kidney disease, and diabetes in every region, causing more than 40% of worldwide deaths from these diseases; high BMI and glucose were each responsible for about 15% of deaths, and high cholesterol for more than 10%. After accounting for multicausality, 63% (10\ub78 million deaths, 95% CI 10\ub71\u201311\ub75) of deaths from these diseases in 2010 were attributable to the combined eff ect of these four metabolic risk factors, compared with 67% (7\ub71 million deaths, 6\ub76\u20137\ub76) in 1980. The mortality burden of high BMI and glucose nearly doubled from 1980 to 2010. At the country level, age-standardised death rates from these diseases attributable to the combined eff ects of these four risk factors surpassed 925 deaths per 100 000 for men in Belarus, Kazakhstan, and Mongolia, but were less than 130 deaths per 100 000 for women and less than 200 for men in some high-income countries including Australia, Canada, France, Japan, the Netherlands, Singapore, South Korea, and Spain. Interpretation The salient features of the cardiometabolic disease and risk factor epidemic at the beginning of the 21st century are high blood pressure and an increasing eff ect of obesity and diabetes. The mortality burden of cardiometabolic risk factors has shifted from high-income to low-income and middle-income countries. Lowering cardiometabolic risks through dietary, behavioural, and pharmacological interventions should be a part of the globalresponse to non-communicable diseases

Mapping soil fractal dimension in agricultural fields with GPR

We documented that the mapping of the fractal dimension of the backscattered Ground Penetrating Radar traces (Fractal Dimension Mapping, FDM) accomplished over heterogeneous agricultural fields gives statistically sound combined information about the spatial distribution of Andosol' dielectric permittivity, volumetric and gravimetric water content, bulk density, and mechanical resistance under seven different management systems. The roughness of the recorded traces was measured in terms of a single number <i>H</i>, the Hurst exponent, which integrates the competitive effects of volumetric water content, pore topology and mechanical resistance in space and time. We showed the suitability to combine the GPR traces fractal analysis with routine geostatistics (kriging) in order to map the spatial variation of soil properties by nondestructive techniques and to quantify precisely the differences under contrasting tillage systems. Three experimental plots with zero tillage and 33, 66 and 100% of crop residues imprinted the highest roughness to GPR wiggle traces (mean <i>H<sub>R/S</sub></i>=0.15), significantly different to Andosol under conventional tillage (<i>H<sub>R/S</sub></i>=0.47)

How does diet influence the reproductive seasonality of tropical freshwater fish?: A case study of a characin in a tropical mountain river

Seasonal breeding of tropical freshwater fish may be synchronized with periods of high food consumption. We explored this hypothesis by studying the relationship between diet and reproductive activity of Creagrutus guanes (Teleostei, Characidae). Our results showed that C. guanes had a generalist and omnivorous diet dominated by aquatic insects (mainly Diptera larvae) and seeds. Creagrutus guanes did not show intersexual or ontogenetic variation in diet. Peaks of feeding activity during rainy months were not synchronized with breeding in dry months. Our results do not support the hypothesis that the reproductive season has to be synchronized with high food consumption. We discussed the hypothesis fat reserves may be an important factor for the desynchronization of peaks of feeding and reproduction as explanation of seasonal breeding of this species

National, regional, and global trends in adult overweight and obesity prevalences.

BACKGROUND: Overweight and obesity prevalence are commonly used for public and policy communication of the extent of the obesity epidemic, yet comparable estimates of trends in overweight and obesity prevalence by country are not available. METHODS: We estimated trends between 1980 and 2008 in overweight and obesity prevalence and their uncertainty for adults 20 years of age and older in 199 countries and territories. Data were from a previous study, which used a Bayesian hierarchical model to estimate mean body mass index (BMI) based on published and unpublished health examination surveys and epidemiologic studies. Here, we used the estimated mean BMIs in a regression model to predict overweight and obesity prevalence by age, country, year, and sex. The uncertainty of the estimates included both those of the Bayesian hierarchical model and the uncertainty due to cross-walking from mean BMI to overweight and obesity prevalence. RESULTS: The global age-standardized prevalence of obesity nearly doubled from 6.4% (95% uncertainty interval 5.7-7.2%) in 1980 to 12.0% (11.5-12.5%) in 2008. Half of this rise occurred in the 20 years between 1980 and 2000, and half occurred in the 8 years between 2000 and 2008. The age-standardized prevalence of overweight increased from 24.6% (22.7-26.7%) to 34.4% (33.2-35.5%) during the same 28-year period. In 2008, female obesity prevalence ranged from 1.4% (0.7-2.2%) in Bangladesh and 1.5% (0.9-2.4%) in Madagascar to 70.4% (61.9-78.9%) in Tonga and 74.8% (66.7-82.1%) in Nauru. Male obesity was below 1% in Bangladesh, Democratic Republic of the Congo, and Ethiopia, and was highest in Cook Islands (60.1%, 52.6-67.6%) and Nauru (67.9%, 60.5-75.0%). CONCLUSIONS: Globally, the prevalence of overweight and obesity has increased since 1980, and the increase has accelerated. Although obesity increased in most countries, levels and trends varied substantially. These data on trends in overweight and obesity may be used to set targets for obesity prevalence as requested at the United Nations high-level meeting on Prevention and Control of NCDs