Evaluación del contenido de selenio en hojas de hierbas nativas de uso tradicional en la alimentación del guatemalteco / Evaluation of selenium content in leaves of native herbs of traditional food use in Guatemala

El selenio (Se) es un elemento esencial para el ser humano que se encuentra en pequeñas cantidades en los suelos, pero se acumula en ciertas plantas, proporcionando beneficios como antioxidante, antiinflamatorio y quemopreventivo por la presencia de unas 25 selenoproteínas que participan en diversas acciones de bienestar, lactancia, desarrollo, reproducción y salud de la progenie. El objetivo de este estudio fue evaluar el contenido de Se en hojas de vegetales utilizados tradicionalmente en la alimentación guatemalteca. Se colectaron hojas de materiales cultivados para los mercados locales de nueve hierbas nativas (Amaranthus hybridus, Cnidoscolus aconitifolius, Crotalaria longirostrata, Dysphania ambrosioides, Lycianthes synanthera, Sechium edule, Solanum americanum, Solanum nigrescens y Solanum wendlandii) y dos introducidas de reconocido uso alimenticio (Moringa oleifera y Spinacia oleracea), se secaron en un horno de convección forzada para lograr una humedad < 10% y se digirieron 0.25 ± 0.02 g de hojas en una mezcla de ácido nítrico y ácido perclórico que se calentó hasta la digestión total de la materia. El Se fue determinado por el método de reflexión total de rayos X, utilizando un estándar interno de itrio (Y) el que se midió utilizando reflectores de cuarzo en un espectrómetro de reflexión total de rayos X. De todas las especies evaluadas, únicamente A. hybridus demostró cantidades cuantificables de Se. Se determinó que 100 g de materia vegetal seca de A. hybridus proporciona 0.355 mg de Se, por lo que su consumo semanal puede contribuir con el requerimiento de este micronutriente para un adulto.

Selenium (Se) is an essential element for the human being; it is in small amounts in the soil but it accumulates in certain plants, providing benefits as antioxidant, anti-inflammatory and chemopreventive, due to the presence of about 25 selenoproteins that participate in different welfare and development actions, lactation, reproduction and health of the progeny. This study aimed to assess Se content in leaves of nine native plants traditionally used in Guatemalan food (Amaranthus hybridus, Cnidoscolus aconitifolius, Crotalaria longirostrata, Dysphania ambrosioides, Lycianthes synanthera, Sechium edule, Solanum americanum, Solanum nigrescens and Solanum wendlandii) and two internationally uses herbs (Moringa oleifera, Spinacia oleracea). Se was determined by total reflection X-ray method. Plants were dried in a forced convection oven to constant weight, then were digested by weighing 0.25 ± 0.02 g of dry plant material with a mixture of nitric and perchloric acid, and warmed to achieve complete digestion. Using a yttrium (Y) internal standard were measured using quartz reflectors Spectrometer Total reflection X-ray. Of all native plant species tested, only A. hybridus there were measurable amounts of Se. It was determined that 100 g of dry plant material of A. hybridus provides 0.355 mg of Se, so its weekly consumption by an adult might contribute to satisfied the requirement of this microelement.

Is otolith microchemistry (Sr: Ca and Ba:Ca ratios) useful to identify Mugil curema populations in the southeastern Caribbean Sea? / A microquímica do otólito é um indicador do habitat de Mugil curema no sudeste do Mar Caribenho?

Abstract The aim of the present study was to evaluate the potential use of otolith microchemistry (Sr:Ca and Ba:Ca ratios) to identify silver mullet, Mugil curema, populations in Southeastern Caribbean Sea. Fish samples were collected in 7 areas of Nueva Esparta State (Venezuela). The otolith Sr:Ca and Ba:Ca ratios and water Sr:Ca were determined (by ICP-OES and EDTA volumetric method). Otoliths Sr:Ca and Ba:Ca ratios and Sr:Ca partition coefficient of mullets in Cubagua island (south of the State) were significantly different from ratios in La Guardia (north of the State). A discriminant analysis of otolith Sr:Ca and Ba:Ca ratios separated Cubagua Island from La Guardia values. These results suggest the existence of different mullet groups in the Southeastern Caribbean Sea. For this, the simultaneous use of Sr:Ca and Ba:Ca ratios could be a potential tool to identify populations in the study area.

Resumo O objetivo do presente estudo foi avaliar o potencial uso da microquímica do otólito (razões Sr:Ca e Ba:Ca) para identificar distintas populações de tainha, Mugil curema, no sudeste do mar caribenho. Os peixes foram coletados em 7 áreas do estado de Nueva Esparta (Venezuela). As razões Sr:Ca e Ba:Ca do otólito e a razão Sr:Ca da água foram determinadas (pelo ICP-OES e EDTA método volumétrico). As razões de Sr:Ca e Ba:Ca dos otólitos e o coeficiente de partição das tainhas da Ilha Cubagua (sul do estado) foram significativamente diferentes das razões de La Guardia (norte do estado). A análise discriminante das razões de Sr:Ca e Ba:Ca dos otólitos separa os valores da Ilha Cubagua e de La Guardia. Estes resultados sugerem a existência de diferentes grupos de Mugil curema no sudeste do mar Caribenho e que o uso simultâneo das razões Sr:Ca e Ba:Ca poderiam ser uma potencial ferramenta para identificar as populações da área de estudo.

Estimation of trace elements in sound and carious enamel of primary and permanent teeth by atomic absorption spectrophotometry: an in vitro study.

The influence of trace elements on the prevalence of caries is a complex subject. However, the demonstration of an inverse relationship between caries prevalence and fluoride (F) intake indicates the potential effect of trace elements on caries. AIMS AND OBJECTIVES: This in vitro study sought to estimate and compare the trace element concentrations in sound and carious enamel of primary and permanent teeth. MATERIALS AND METHODS: Forty sound and carious primary and permanent teeth, extracted from children and adolescents of Davangere city, were collected. The teeth were divided into four groups (of ten each) and enamel samples were prepared by mechanical grinding. The trace elements were estimated using atomic absorption spectrophotometer. RESULTS AND CONCLUSIONS: The results of our study showed the presence of 18 trace elements (F, Sr, K, Al, Si, Ni, B, Fe, Cu, Mn, Co, Cr, Zn, Mg, Se, Pb, Mo, and V) in the enamel of sound and carious primary and permanent teeth. The mean, standard deviation, and range (at 95% confidence level) were calculated for each element. The concentrations of F, Sr, and K were significantly ( P <0.05) higher in sound enamel of permanent teeth than in sound enamel of primary teeth. The concentrations of F, Sr, K, Al, and Fe were significantly ( P <0.05) higher in sound enamel of permanent teeth than in carious enamel of permanent teeth. The concentrations of F, K, and Si were significantly ( P <0.05) higher in sound enamel of primary teeth than in carious enamel of primary teeth.

Estrôncio e osteodistrofia de origem renal: breve revisão da literatura / Strontium and renal osteodystrophy: brief review of literature

Strontium is the more abundant element in the earth representing almost 0.34 per cent of the whole earth eruptive igneous rocks. Is is naturally presnt in food, water, air and soil and also used in many industrial activities. It is absorbed in the intestinal mucosa, stored in bone tisue and excreted by the kidney. Some metals such as aluminium and strontium are found in dialysis solutions and medications used as a phosphate binder. Several studies have shown the multifactorial etiology of renal osteodystrophy associated with dialysis as well as the important role of metals, such as aluminium and strontium, on the disease development. This study is a brief review of the literature focusing on the toxic action of strontium in bone and its role in the renal osteodystrophy development...

Diet and nutrition of prehistoric populations at the alluvial banks of the Paraná river

This study attempts to characterize the health status and diet of prehistotic populations (1000-2000 years BP), dwelling at both banks of Parana River, between 29ºS and 32ºS. The data obtained suggest that these prehistoric populations had an adequate nutritional status, with complete proteins in the diet, as suggested by the ratio strontium/calcium in their bone mineral (0.71 + 0.04 mug Srx1000/mg Ca). The overall frequency of dental caries (4.9 percent) coincides with that reported for hunters-gatherers. The average mineral densities of the tibiae of adult subjects exhumed at two sites (males: 1.51 + 0.07 gr/cm2; females: 1.24 + 0.06 gr/cm2) suggested that they had significant bone mass, an asset compatible with adequate nutrition. In metacarpals, the amount of cortical tissue also suggests bone mass comparable to contemporaneous controls. The growth and development of the prehistoric populations studied are deemed normal as shown by the clear sexual dimorphism of their estimated heights at adult age (males: 177-183 cm; females 152-166 cm) and their bone mass.

The comparative evaluation of release profiles of aluminium, fluoride, sodium and strontium by resin modified and conventional glass polyalkenoate cements in neutral and acidic medium--an in vitro study.

The present study was carried out to evaluate the Al, F, Na and Sr release profiles of conventional and resin modified glass polyalkenoate cements in neutral (deionized water) and acidic medium (lactic acid). Twelve pellets of each material were prepared under standardised conditions and were immersed in their respective solutions for a study period of 90 days. Fluoride analysis was carried out by Orion Electrode and the other elemental analysis were done by Atomic Absorption Spectrophotometer. Statistical analysis revealed no significant difference in the Al, F and Na release profiles between the two materials in both neutral and acidic media.