Why are mineralocorticoid receptor antagonists cardioprotective?

Two clinical trials, the Randomized ALdosterone Evaluation Study (RALES) and the EPlerenone HEart failure and SUrvival Study (EPHESUS), have recently shown that mineralocorticoid receptor (MR) antagonists reduce mortality in patients with heart failure on top of ACE inhibition. This effect could not be attributed solely to blockade of the renal MR-mediated effects on blood pressure, and it has therefore been proposed that aldosterone, the endogenous MR agonist, also acts extrarenally, in particular in the heart. Indeed, MR are present in cardiac tissue, and possibly aldosterone synthesis occurs in the heart. This review critically addresses the following questions: (1) is aldosterone synthesized at cardiac tissue sites, (2) what agonist stimulates cardiac MR normally, and (3) what effects are mediated by aldosterone/MR in the heart that could explain the beneficial effects of MR blockade in heart failure? Conclusions are that most, if not all, of cardiac aldosterone originates in the circulation (i.e., is of adrenal origin), and that glucocorticoids, in addition to aldosterone, may serve as the endogenous agonist of cardiac MR. MR-mediated effects in the heart include effects on endothelial function, cardiac fibrosis and hypertrophy, oxidative stress, cardiac inotropy, coronary flow, and arrhythmias. Some of these effects occur via or in synergy with angiotensin II, and involve a non-MR-mediated mechanism. This raises the possibility that aldosterone synthase inhibitors might exert beneficial effects on top of MR blockade

Oxidative discolouration in whole-head and cut lettuce: biochemical and environmental influences on a complex phenotype and potential breeding strategies to improve shelf-life

Lettuce discolouration is a key post-harvest trait. The major enzyme controlling oxidative discolouration has long been considered to be polyphenol oxidase (PPO) however, levels of PPO and subsequent development of discolouration symptoms have not always correlated. The predominance of a latent state of the enzyme in plant tissues combined with substrate activation and contemporaneous suicide inactivation mechanisms are considered as potential explanations for this phenomenon. Leaf tissue physical properties have been associated with subsequent discolouration and these may be influenced by variation in nutrient availability, especially excess nitrogen and head maturity at harvest. Mild calcium and irrigation stress has also been associated with a reduction in subsequent discolouration, although excess irrigation has been linked to increased discolouration potentially through leaf physical properties. These environmental factors, including high temperature and UV light intensities, often have impacts on levels of phenolic compounds linking the environmental responses to the biochemistry of the PPO pathway. Breeding strategies targeting the PALand PPOpathway biochemistry and environmental response genes are discussed as a more cost-effective method of mitigating oxidative discolouration then either modified atmosphere packaging or post-harvest treatments, although current understanding of the biochemistry means that such programs are likely to be limited in nature and it is likely that they will need to be deployed alongside other methods for the foreseeable future

Modeling the drying of a deep bed of Ilex paraguariensis in an industrial belt conveyor dryer

The evolution of temperature and moisture content of leaves and twigs of yerba maté on different levels of a through-flow dryer was investigated by modeling heat and mass transfer using the finite difference method. To validate the model, the temperature and moisture profiles were used to estimate chlorophyll losses. Great variations were obtained in moisture, temperature, and chlorophyll content at different levels of the bed. Leaf temperature quickly increased in the former nodes, and it then increased slowly until it reached air temperature. In the twigs, the temperature increase was slow and the air temperature was never reached.Fil: Schmalko, M. E.. Universidad Nacional de Misiones; ArgentinaFil: Peralta, Juan Manuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; ArgentinaFil: Alzamora, Stella Maris. Universidad de Buenos Aires; Argentin

Minimally processed foods

One of the major growth segments in the food retail industry is minimally processed (MP) foods. This relatively new market trend has strived to develop new technologies or new applications of traditional technologies to preserve the characteristics of excellence in the products, extend shelf-life and improve their microbiological safety. Most of these technologies for gentle preservation are based on the hurdle concept. Additives, modified-atmosphere packaging, the use of essential oils as antioxidants and antimicrobials, the application of edible films, high hydrostatic pressure, high intensity pulsed electric field, high-intensity light pulses, ultraviolet radiation, high-power ultrasound, pulsed light and ozone are some of the leading preservation factors in recent years. The aim of this chapter is to revise the minimal process concept and to give an overview of mild technologies developed to extend the shelf-life of these products.Fil: Alzamora, Stella Maris. Universidad de Buenos Aires; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Lopez Malo, A.. Universidad de las Américas Puebla; MéxicoFil: Tapia, M. S.. Universidad Central de Venezuela; VenezuelaFil: Welti Chanes, J.. Tecnológico de Monterrey; Méxic

Multi-Level approach for the analysis of water effects in corn flakes

The purpose of this work was to analyze the effect of water on thermal transitions, mechanical properties, and molecular mobility in corn flakes (CF), and their relationships. Commercial common (CCF) and sugar-frosted (SCF) corn flakes were studied in a water content (wc) range from 5 to 20 (% dry basis). The slope of 1H NMR spin−spin relaxation time T2* (determined by FID) versus temperature plot changed close to Tg. Compression force showed a maximum at wc of ca. 12 and 16% (db) for SCF and CCF, respectively. 1H NMR complemented DSC data in determining the temperature dependence of water and solid mobility, in order to assess quality of laminated corn products. The results of the present work indicate that while the compression force showed a maximum value as a function of water content, Tg values determined by DSC or by spin−spin relaxation decreased progressively with increasing water content.EEA PergaminoFil: Farroni, Abel Eduardo. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Pergamino. Laboratorio Calidad de Alimento, Suelo y Agua; ArgentinaFil: Matiacevich, Silvia B. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Industrias; ArgentinaFil: Guerrero, Sandra. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Industrias; ArgentinaFil: Alzamora, Stella. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Industrias; Argentina.Fil: Buera, María del Pilar. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Industrias; Argentin

Effect of the high-pressure assisted-infusion processing on nutritional and antioxidantproperties of mango cubes

The aim of this work was to evaluate the effect of the high-pressure assisted-infusion processing on the nutritional and functional properties of mango cubes immersed in a solution of sorbitol and calcium lactate. Three factors were studied: sorbitol concentration (20°Brix-40°Brix-60°Brix), calcium lactate concentration (0% w/w − 1% w/w − 2% w/w) and the pressure level (0.1 MPa–300 MPa-600 MPa). Sugar (sorbitol, glucose and sucrose), calcium and total phenols content and antioxidant capacity were determined. Results showed that the increase of sorbitol concentration from 20°Brix to 40°Brix caused higher sorbitol uptake and lixiviation of the natural compo in mango cubes. However, the increase of sorbitol concentration from 40°Brix to 60°Brix, had no significant effect on the diffusion of solutes. The high-pressure processing (HPP) favored the diffusion of solutes from solution to fruit, while the addition of the calcium counteracted this effect in most cases. Based on these results, the combined effect of 300 MPa and 60°Brix-2% calcium lactate was the most effective at preserving natural compounds of mango and conferred distinctive properties giving an added value to the final product due to its important nutritional implications. Therefore, high-pressure assisted-infusion processing could be considered as an effective method to preserve mango cubes with an acceptable nutritional value. Industrial relevance The present work showed that high-pressure assisted-infusion processing could be considered an alternative to develop mango-based products. Results showed that this process would allow preserving most of the natural compounds of the mango pieces, in addition to achieving distinctive characteristics, as a source of calcium. Therefore, the application of high-pressure assisted-infusion processing could open new opportunities for food industries to develop fresh and value-added products with characteristics similar to fresh fruit.Instituto de Investigación de Tecnología de AlimentosFil: Perdomo Lamilla, Carolina. Universidad de Buenos Aires. Facultad de Ciencias Naturales y Exactas; Argentina.Fil: Vaudagna Sergio Ramon. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Investigación Tecnología de Alimentos; Argentina.Fil: Vaudagna Sergio Ramon. Instituto de Ciencia y Tecnología de Sistemas Alimentarios Sustentables (UEDD INTA CONICET); Argentina.Fil: Alzamora, Stella M. Universidad de Buenos Aires. Facultad de Ciencias Naturales y Exactas; Argentina.Fil: Alzamora, Stella M. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina.Fil: Mozgovoj, Marina Valeria. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Investigación Tecnología de Alimentos; Argentina.Fil: Mozgovoj, Marina Valeria. Instituto de Ciencia y Tecnología de Sistemas Alimentarios Sustentables (UEDD INTA CONICET); Argentina.Fil: Rodriguez, Anabel. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Investigación Tecnología de Alimentos; Argentina.Fil: Rodriguez, Anabel. Instituto de Ciencia y Tecnología de Sistemas Alimentarios Sustentables (UEDD INTA CONICET); Argentina

Study of UV-C treatments on postharvest life of blueberries ‘O'Neal’ and correlation between structure and quality parameters

The effect of different doses of UV-C light (5.3, 8.3 and 11.4 kJ/m2) on native mycobiota and Botrytis cinerea incidence, micro and ultrastructure, biomechanical properties and weight loss of blueberry fruit cv. O'Neal during 20 days of storage at 8 ± 1 °C was evaluated. Decay incidence was significantly reduced by all UV-C light doses for both, native mycobiota and inoculated B. cinerea. The highest UV-C dose studied (11.4 kJ/m2) was the most effective indelaying the onset of fungal and B. cinerea infection (6 and 4 days, respectively). UV-C irradiation caused some distinctive changes in fruit structure characterized by redistribution, alteration and partial removal of epicuticular waxes, reinforcement of epicarp cell walls, and modifications in the cuticle. Biomechanical parameters were not affected by UV-C treatments excepting at day 15 where irradiated samples showed higher values of rupture force (FR) and deformation (D). Structure changes partially explained the significant increase in weight loss, FR and D values in irradiated fruit after 15 days of storage. UV-C irradiation could be an alternative for delaying and reducing fungal infection. However, postharvest shelf-life of irradiated blueberries could be limited by the negative effect on weight loss

Determination of Dicofol in Tea Using Surface-Enhanced Raman Spectroscopy Coupled Chemometrics

Dicofol is a highly toxic residual pesticide in tea, which seriously endangers human health. A method for detecting dicofol in tea by combining stoichiometry with surface-enhanced Raman spectroscopy (SERS) technology was proposed in this study. AuNPs were prepared, and silver shells were grown on the surface of AuNPs to obtain core-shell Au@AgNPs. Then, the core-shell Au@AgNPs were attached to the surface of a PDMS membrane by physical deposition to obtain a Au@AgNPs/PDMS substrate. The limit of detection (LOD) of this substrate for 4-ATP is as low as 0.28 x 10(-11) mol/L, and the LOD of dicofol in tea is 0.32 ng/kg, showing high sensitivity. By comparing the modeling effects of preprocessing and variable selection algorithms, it is concluded that the modeling effect of Savitzky-Golay combined with competitive adaptive reweighted sampling-partial least squares regression is the best (Rp = 0.9964, RPD = 10.6145). SERS technology combined with stoichiometry is expected to rapidly detect dicofol in tea without labels