Maria Daniela Defagó

Potent Limonoid Insect Antifeedant from Melia azedarach

Systematic fractionation of a fruit extract from Argentine Melia azedarach L., which was monitored by an insect antifeedant bioassay, led to the isolation of meliartenin, a limonoid antifeedant, which existed as a mixture of two interchangeable isomers. At 4 μg/cm2 and 1 μg/cm2, the isomeric mixture was as active as azadirachtin in strongly inhibiting the larval feeding of Epilachna paenulata Germ. (Coleoptera: Coccinellidae) and the polyphagous pest, Spodoptera eridania (Lepidoptera: Noctuidae), respectively.

Influence of Food Patterns on Endothelial Biomarkers: A Systematic Review

The purpose of this study was to conduct a systematic review on the association of food patterns (FPs) and endothelial biomarkers. An electronic literature search from 1990 to 2012 was conducted and reference lists and experts were consulted. Studies without dietary intervention and without language restrictions were considered. Preferred Reporting Items for Systematic Reviews and Meta‐Analyses guidelines were employed. Methodological quality was assessed by Strengthening the Reporting of Observational Studies in Epidemiology guidelines. A total of 546 references were identified, of which 8 were finally included. Several FPs were identified. Healthy FPs (abundant in fruits and vegetables) had a beneficial impact on endothelial function as estimated by circulating levels of biomarkers such as C‐reactive protein, soluble intercellular adhesion molecule 1, soluble vascular adhesion molecule 1, and E‐selectin molecules. Westernized patterns (higher intakes of processed meats, sweets, fried foods, and refined grains) were positively associated with inflammation molecules and atherogenic promoters. The study of FPs in relation to endothelial function contributes to the development of dietary recommendations for improved cardiovascular health and therefore a better lifestyle.

Common Genetic Variants in the Endothelial System Predict Blood Pressure Response to Sodium Intake: The GenSalt Study

BACKGROUND We examined the association between 14 endothelial system genes and salt-sensitivity of blood pressure (BP). METHODS After a 3-day baseline examination, during which time the usual diet was consumed, 1,906 Chinese participants received a 7-day low-sodium diet (51.3 mmol of sodium/day) followed by a 7-day high-sodium diet (307.8 mmol of sodium/day). BP measurements were obtained at baseline and at the end of each intervention using a random-zero sphygmomanometer. RESULTS The DDAH1 rs11161637 variant was associated with reduced BP salt sensitivity, conferring attenuated systolic BP (SBP) and mean arterial pressure (MAP) decreases from baseline to the low-sodium intervention (both P = 2×10(-4)). Examination of genotype-sex interactions revealed that this relation was driven by the strong associations observed in men (P for interactions = 1.10×10(-4) and 0.008, respectively). When switching from the low- to high-sodium intervention, increases in diastolic BP (DBP) and MAP were attenuated by the COL18A1 rs2838944 minor A allele (P = 1.41×10(-4) and 1.55×10(-4), respectively). Conversely, the VWF rs2239153 C variant was associated with increased salt sensitivity, conferring larger DBP and MAP reductions during low-sodium intervention (P = 1.22×10(-4) and 4.44×10(-5), respectively). Ten variants from 3 independent SELE loci displayed significant genotype-sex interactions on DBP and MAP responses to low-sodium (P for interaction = 1.56×10(-3) to 1.00×10(-4)). Among men, minor alleles of 4 correlated markers attenuated BP responses to low-sodium intake, whereas minor alleles of another 4 correlated markers increased BP responses. No associations were observed in women for these variants. Further, qualitative interactions were shown for 2 correlated SELE markers. CONCLUSIONS These data support a role for the endothelial system genes in salt sensitivity.

Validation of a self-administered FFQ in adults in Argentina, Chile and Uruguay.

OBJECTIVE To assess the reproducibility and validity among adults in the Southern Cone of Latin America (Argentina, Chile and Uruguay) of a self-administered FFQ to be used in the CESCAS I Study, an ongoing observational prospective cohort study to detect and follow up CVD and their risk factors, as well as in other epidemiological studies. DESIGN Relative validity of the FFQ was evaluated by comparing nutrient and selected food group intakes with those from three 24 h recalls (24HR) administered over 6 months. The FFQ was administered at baseline (FFQ1) and again after 3 months (FFQ2). SETTING Primary-care centres in Argentina, Chile and Uruguay. SUBJECTS Adults (n 147) aged 21-74 years. RESULTS Reproducibility (FFQ1 v. FFQ2): the intra-class correlation coefficients for nutrients ranged from 0·52 (potassium) to 0·74 (fat). Validity (FFQ1 v. the average of three 24HR): the Pearson correlations for energy-adjusted nutrients ranged from 0·39 (thiamin and cholesterol) to 0·59 (carbohydrate). Joint classification: overall, 66 % of participants in the lowest 24HR quintile were in the lowest one or two FFQ1 quintiles, and 62 % of those in the highest 24HR quintile were in the highest one or two FFQ1 quintiles. On average, only 4 % were misclassified into extreme quintiles. CONCLUSIONS The FFQ version for the Southern Cone seems to present moderate to acceptable relative validity and reliability for its use in the CESCAS I Study to measure dietary exposure.

Desarrollo de un programa informático para estudios nutricionales

Se desarrollo el programa informatico Interfood v. 1.3 para procesar la informacion alimentaria y generar datos sobre el consumo dietetico -en terminos de alimentos, nutrientes y sustancias fitoquimicas- validos para realizar estudios nutricionales y epidemiologicos. El programa se basa en tres componentes fundamentales: el cuestionario de frecuencia de consumo alimentario (CFCA); una base de datos de alimentos frecuentes y su contenido en 131 compuestos (macro y micronutrientes y sustancias fitoquimicas); y una base de datos relacional que asocia la informacion del CFCA con la base de datos de alimentos. De esta forma, el programa informatico Interfood calcula la cantidad de cada uno de los alimentos y los nutrientes y las sustancias fitoquimicas que una persona consume por dia, semana y mes. Interfood es un programa de codigo abierto, por lo que sus bases de datos se pueden modificar y actualizar de acuerdo con las necesidades de la investigacion. Este programa ya ha demostrado su utilidad en diversas investigaciones nutricionales y epidemiologicas.

Nutritional Epidemiological Tools for Sodium Intake

Dietary sodium is a determinant of blood pressure. Modern diets provide excessive amounts of salt, and in developed and developing countries the intake of processed foods with high salt levels is increasing. In order to establish effective nutrition policy, it is necessary to know the quantity of consumed salt as well as identify the main dietary sources of salt. Different methods are currently in use for estimating dietary sodium intake. The use of 24-hour urinary collection to assess sodium intake is considered the most accurate method but involves considerable burden for participants. The use of the spot urine method has been proposed as an alternative however in not recommended without calibration methodology. Sodium estimates based on dietary surveys include several methods such the 24-hour dietary recall, the food frequency questionnaire, and the diet record, with often under-estimates intake due to under-reporting and difficulties quantifying sodium in concentration discretionary salt and recipes. Food compositions databases and nutritional softwares can be used to assess sodium consumption. More research is necessary to improve nutritional epidemiological tools for sodium intake