Phenotypic and genotypic characterization of lactic acid bacteria isolated from cow, ewe and goat dairy artisanal farmhouses

Lactic acid bacteria collected from artisanal farmhouses were characterized using a polyphasic approach. Phenotypic methods including biochemical assays, ribosomal DNA restriction analysis and 16S rDNA sequence analysis were performed. This approach provides accuracy for identification, and helps to avoid the loss of natural biodiversity including potentially valuable strains

La piramide del estilo de vida saludable para niños y adolescentes

Introduction: Increasing evidence demonstrates that risk factors for chronic diseases are established during childhood and adolescence. Consensus about the need to increase prevention efforts makes the adoption of a healthy lifestyle seem desirable from early childhood onwards. After reviewing educational tools for children and adolescents aimed at promoting a healthy lifestyle, it was recognized that there was a need to develop a simple educational tool specifically designed for these age groups. Methods: Development of the healthy lifestyle pyramid for children and adolescents. Results: We propose a three-dimensional, truncated and staggered pyramid with 4 faces and a base, which introduces a completely new concept that goes beyond other published pyramids. Each of the faces is oriented towards achieving a different goal. Two faces (faces 1 and 2) are formulated around achieving a goal on a daily basis (daily food intake, face 1, and daily activities, face 2). Face 3 is an adaptation of the traditional food guide pyramid, adapted to children’s energy, nutritional and hydration needs. Face 4 deals with both daily and life-long habits. On the base of the pyramid, there is advice about adequate nutrition alternating with advice about physical activity and sports. Conclusion: The Healthy Lifestyle Pyramid© is specifically developed for children and adolescents according to current scientific knowledge and evidence-based data and includes easy-to-follow advice and full colour pictures. Following these guidelines should improve health and reduce risk factors, promoting enjoyable and appropriate development towards adulthood.Introducción: En la actualidad, existe evidencia científica de que los factores de riesgo de enfermedades crónicas se establecen durante la infancia y la adolescencia. La adopción de un estilo de vida saludable parece deseable desde edades tempranas existiendo un consenso cada vez mayor hacia la prevención. Al revisar las herramientas educativas existentes para niños y adolescentes dirigidas a la mejora de la adquisición de un estilo de vida saludable, se advirtió de la necesidad de desarrollar un instrumento educativo desarrollado específicamente para estos grupos de edad. Métodos: Desarrollo de la pirámide de estilo de vida saludable para los niños y adolescentes. Resultados: Nuestra propuesta trata de una pirámide tridimensional con 4 caras y una base, truncada y escalonada, introduciendo un nuevo concepto que va más allá de lo publicado en otras pirámides. Cada una de las caras se orienta hacia la consecución de un objetivo. Las dos primeras caras (caras 1 y 2) se han formulado con el fin de lograr un objetivo sobre una base diaria (alimentación diaria, la cara 1, frente a las actividades diarias la cara 2). La Cara 3 es una adaptación de la tradicional pirámide de alimentos, adecuada a las necesidades de energía, nutrientes e hidratación de los niños. La Cara 4 muestra los hábitos de higiene y salud que se deben mantener durante toda la vida. En la base de la pirámide, se alternan mensajes sobre la nutrición adecuada con mensajes relacionados con la actividad física y el deporte. Conclusión: La Pirámide del Estilo de Vida Saludable© se ha desarrollado específicamente para niños y adolescentes, teniendo en cuenta los actuales conocimientos científicos. Incluye mensajes fáciles de entender e imágenes a todo color. El seguimiento de estas directrices debería contribuir a mejorar la salud y a la reducción de los factores de riesgo en la edad adulta, al tiempo que se divierten y crecen de una manera aconsejable.The pyramid has been edited with the support of Coca-Cola España. The pyramid can be downloaded at EXERNET (www.spanishexernet.com), supported by the Spanish Ministry of Education. Reproduction permitted with the citation of this article

DETECCION MEDIANTE PCR-RFLP DE Fusarium oxysporum f.sp. fragariae AGENTE CAUSAL DE FUSARIOSIS EN FRUTILLA

La frutilla es una de las frutas de importante crecimiento económico tanto en Chile como a nivel Mundial. Desde hace varios años su producción haexperimentado pérdidas económicas, principalmente a causa de las enfermedades producidas por Fusarium oxysporum f.sp. fragariae (Fof). Este patógeno, se ha propagado rápidamente por casi todo el mundo debido a su difícil diagnóstico y actualmente la única manera dedetectarlo es mediante test de patogenicidad, técnica laboriosa que requiere de bastante tiempo y material, lo que dificulta su detección oportuna. Debido a que el diagnóstico genético y las técnicas moleculares son metodologías rápidas y altamente eficaces, el objetivo deeste trabajo fue diseñar un método para detectar a Fof, con el fin de controlar y certificar el ingreso o salida del país de este patógeno.Para esto se amplificó el gen «Factor de Elongación 1-α» (EF1-α), en 25 cepas de F. oxysporum aisladas desde diversas localidades de la VIII región y R. Metropolitana, 4 cepas otorgadas por el laboratorioNacional del Servicio Agrícola y Ganadero (SAG), y 4 cepas patogénicas controles importadas desde ATCC, EE.UU. Posteriormente por digestión con endonucleasas MseI y MspI se logró diferenciar las cepas de Fusarium oxysporum f.sp. fragariae de las respectivas cepas nopatogénicas de este hongo. Estos resultados fueron confirmados mediante electroforesis en geles de poliacrilamida denaturante, RFLP con dos endonucleasas y parcialmente mediante secuenciación delproducto amplificado de Fof, revelándose de esta manera la eficacia de esta metodología.

Is maize B chromosome preferential fertilization controlled by a single gene?

In previous work, genotypes for high and low B chromosome transmission rate were selected from a native race of maize. It was demonstrated that the B transmission is genetically controlled. The present work reports the fourth and fifth generations of selection and the F1 hybrids between the lines. The native B is characterized by a constant behaviour, with normal meiosis and nondisjunction in 100% of postmeiotic mitosis. It is concluded that genetic variation for B transmission between the selected lines is due to the preferential fertilization process. The F1 hybrids show intermediate B transmission rate between the lines. They are uniform, the variance of the selected character being one order of magnitude lower than that of the native population. In addition, 0B×2B and 2B×2B crosses were made to study the effect of the presence of B chromosomes in the female parent, resulting in non-significant differences. Several crosses were made both in Buenos Aires and in Madrid to compare the possible environmental effect, but significant differences were not found. Our results are consistent with the hypothesis of a single major gene controlling B transmission rate in maize, which acts in the egg cell at the haploid level during fertilization. It is also hypothesized that maize Bs use the normal maize fertilization process to promote their own transmission.Facultad de Ciencias Agrarias y Forestale

Is maize B chromosome preferential fertilization controlled by a single gene?

In previous work, genotypes for high and low B chromosome transmission rate were selected from a native race of maize. It was demonstrated that the B transmission is genetically controlled. The present work reports the fourth and fifth generations of selection and the F1 hybrids between the lines. The native B is characterized by a constant behaviour, with normal meiosis and nondisjunction in 100% of postmeiotic mitosis. It is concluded that genetic variation for B transmission between the selected lines is due to the preferential fertilization process. The F1 hybrids show intermediate B transmission rate between the lines. They are uniform, the variance of the selected character being one order of magnitude lower than that of the native population. In addition, 0B×2B and 2B×2B crosses were made to study the effect of the presence of B chromosomes in the female parent, resulting in non-significant differences. Several crosses were made both in Buenos Aires and in Madrid to compare the possible environmental effect, but significant differences were not found. Our results are consistent with the hypothesis of a single major gene controlling B transmission rate in maize, which acts in the egg cell at the haploid level during fertilization. It is also hypothesized that maize Bs use the normal maize fertilization process to promote their own transmission.Facultad de Ciencias Agrarias y Forestale

Algoritmo para el diagnóstico precoz de la deficiencia de vitamina B12 en ancianos

Background: The elderly population is particularly at risk for developing vitamin B12-deficiency. Serum cobalamin does not necessarily reflect a normal B12 status. The determination of methylmalonic acid is not available in all laboratories. Issues of sensitivity for holotranscobalamin and the low specificity of total homocysteine limit their utility. The aim of the present study is to establish a diagnostic algorithm by using a combination of these markers in place of a single measurement. Methods: We compared the diagnostic efficiency of these markers for detection of vitamin B12 deficiency in a population (n = 218) of institutionalized elderly (median age 80 years). Biochemical, haematological and morphological data were used to categorize people with or without vitamin B12 deficiency. Results: In receiver operating curves characteristics for detection on vitamin B12 deficiency using single measurements, serum folate has the greatest area under the curve (0.87) and homocysteine the lowest (0.67). The best specificity was observed for erythrocyte folate and methylmalonic acid (100% for both) but their sensitivity was very low (17% and 53%, respectively). The highest sensitivity was observed for homocysteine (81%) and serum folate (74%). When we combined these markers, starting with serum and erythrocyte folate, followed by holotranscobalamin and ending by methylmalonic acid measurements, the overall sensitivity and specificity of the algorithm were 100% and 90%, respectively. Conclusion: The proposed algorithm, which combines erythrocyte folate, serum folate, holotranscobalamin and methylmalonic acid, but eliminate B12 and tHcy measurements, is a useful alternative for vitamin B12 deficiency screening in an elderly institutionalized cohort.Introducción: Los mayores son una población que presenta un riesgo importante de desarrollar una deficiencia de vitamina B12, pero las concentraciones de cobalamina en suero no reflejan necesariamente un estado abnormal en el estado de B12 . Existen biomarcadores asociados a la vitamina B12: el ácido metilmalónico no está disponible en todos los laboratorios, la holotranscobalamina es poco sensible y la homocisteína presenta una baja especificidad. El objetivo del presente estudio es establecer un algoritmo de diagnóstico mediante el uso de una combinación de estos biomarcadores en lugar de la medición de uno sólo de ellos. Métodos: Se comparó la eficacia diagnóstica de estos marcadores para la detección de deficiencia de vitamina B12 en una población (n = 218) de ancianos institucionalizados (edad media 80 años). Los parámetros bioquímicos, hematológicos y morfológicos fueron utilizados para clasificar a los sujetos con o sin deficiencia de vitamina B12. Resultados: Se establecieron las curvas ROC (Receiver Operating Curves) para determinar la eficacia diagnóstica de cada parámetro, tomado individualmente. El folato sérico tenía la mayor área bajo la curva (0,87) y la homocisteína la más baja (0,67). Se observó que la mejor especificidad la presentaba el folato eritrocitario y el ácido metilmalónico (100% para ambos), pero sus sensibilidades eran muy bajas (17% y 53%, respectivamente). Y se observó que la sensibilidad más alta la presentaba la homocisteína (81%) y el folato sérico (74%), pero en contrapartida una especificidad baja. Cuando se combinaron estos marcadores, iniciando las determinaciones con el folato sérco y eritrocitario, seguido por holotranscobalamina y terminando por las mediciones de ácido metilmalónico, la sensibilidad y especificidad global del algoritmo fueron 100% y 90%, respectivamente. Conclusión: El algoritmo propuesto, que combina la determinación de folato sérico y eritrocitario, holotranscobalamina y ácido metilmalónico, sin necesidad de evaluar la vitamina B12 y la homocisteína, es una alternativa útil para la detección de un estado abnormal del estado de vitamina B12 en una población de ancianos institucionalizados

Palm Oil on the Edge

Internationally recognized Spanish experts in the food industry, nutrition, toxicology, sustainability, and veterinary science met in Madrid on July 2018 to develop a consensus about palm oil (PO) as a food ingredient. Their aim was to provide a useful, evidence-based point of reference about PO. Scientific evidence about the role of PO in food safety, nutrition and sustainability was analyzed. Main conclusions were: (1) RSPO foundation responded to the environmental impact of palm crops. The Amsterdam Declaration pursues the use of 100% sustainable PO in Europe by 2020. Awareness about choosing sustainable products will help to maintain local economies and environments in the producing countries; (2) evidence shows that a moderate intake of PO within a healthy diet presents no risks for health. No evidence justifies any change fat intake recommendations; (3) food industry is interested in assuring safe, sustainable and high-quality products. The use of certified sustainable PO is increasing; and (4) there is no evidence associating PO consumption and higher cancer risk, incidence or mortality in humans. Tolerable daily intake (TDI) for toxic contaminants (2-and 3-monochloropropanediols (MCPDs), glycidyl esters (GEs)) have been established by JECFA and EFSA. Consequently, the European Commission has modified the Contaminants Regulation for GEs and it is still working on 3-MCPDs’

Extrusion of Ingot and Powder Metallurgy Aluminum Matrix Composites Profiles

Several profiles with the same extrusion ratio were extruded from three monolithic alloys and five aluminum matrix composites (AMCs) prepared by ingot and powder metallurgy (PM). Specifically, AA6061 and AA6063 were reinforced by 10 and 25 vol.% of Al2O3 and MoSi2 intermetallic particles. To study the wear of the dies, high temperature pin-on-disk tests were performed. The results show that the composite profiles present high surface and dimensional quality and that the die steel wears slightly more against the cast composite. Maximum extrusion pressure (Pmax) depends on profile shape and increases in the following order: bar, T, L and U, and tube. It also increases as volume fraction of reinforcement increases. In general, cast materials are easier to extrude than PM ones, and MoSi2 reinforced AMCs are easier to extrude than Al2O3 ones. AMCs processed by PM have significantly higher hardness than the cast AMC and the monolithic alloys. The PM composites do not need any heat treatment to acquire maximum hardness. By adding reinforcing particles to aluminum, a significant increase in tensile strength and stiffness occur. The high tensile strength and modulus of the present PM composites, without a decrease in specific properties, makes these AMCs interesting for structural applications.Spanish project TRACE2009_0251 from MICINN, Spain, and EXTRUGASA, Galicia, Spain, are gratefully acknowledged. Thanks are also due to Amalia San Román and Miguel Acedo for their help with the experimental work.Peer reviewe

Predicción de fractura en alambres trefilados en una pasada

Un problema recurrente en el proceso de trefilado de alambres es la aparición de una microcavidad interna conocida como “estallido central” la que puede crecer hasta cortar el alambre, obligando a detener el proceso. En este trabajo se presenta un estudio numérico del proceso de trefilado de alambres de una aleación de aluminio Al-2011, con la intención de evaluar la evolución de las variables internas (deformación plástica efectiva y triaxialidad) y su incidencia en el desarrollo de la fractura de los alambres trefilados en una pasada. La caracterización del material y del criterio de fractura usado en el presente trabajo se realiza mediante un ensayo de tracción uniaxial y los parámetros obtenidos se utilizan en simulaciones numéricas de 6 configuraciones geométricas distintas: el ángulo de la hilera se mantiene constante y el diámetro inicial del alambre aumenta gradualmente para tener 6 niveles de reducción distintos. La validación se realiza mediante el análisis de la fuerza de tiro de estas mismas mediciones experimentales reportadas en la literatura. Al final de este trabajo se presenta un mapa de zonas seguras e inseguras, según los resultados obtenidos del criterio de fractura para las configuraciones geométricas estudiadas.Publicado en: Mecánica Computacional vol. XXXV no.35Facultad de Ingenierí

Palm Oil on the Edge

Internationally recognized Spanish experts in the food industry, nutrition, toxicology, sustainability, and veterinary science met in Madrid on July 2018 to develop a consensus about palm oil (PO) as a food ingredient. Their aim was to provide a useful, evidence-based point of reference about PO. Scientific evidence about the role of PO in food safety, nutrition and sustainability was analyzed. Main conclusions were: (1) RSPO foundation responded to the environmental impact of palm crops. The Amsterdam Declaration pursues the use of 100% sustainable PO in Europe by 2020. Awareness about choosing sustainable products will help to maintain local economies and environments in the producing countries; (2) evidence shows that a moderate intake of PO within a healthy diet presents no risks for health. No evidence justifies any change fat intake recommendations; (3) food industry is interested in assuring safe, sustainable and high-quality products. The use of certified sustainable PO is increasing; and (4) there is no evidence associating PO consumption and higher cancer risk, incidence or mortality in humans. Tolerable daily intake (TDI) for toxic contaminants (2-and 3-monochloropropanediols (MCPDs), glycidyl esters (GEs)) have been established by JECFA and EFSA. Consequently, the European Commission has modified the Contaminants Regulation for GEs and it is still working on 3-MCPD