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This study optimizes the pyrodextrinization of yam (Dioscorea sp.) starch isolated from tubers grown in Brazil to produce a yellow pyrodextrin with the lowest enzymatically available starch (AS) content and color difference (ΔE) index. At 140 °C (fixed heating temperature), the effects of acid concentration (0.65 - 2.99 g of HCl/kg of starch) and incubation time (53 - 307 min) on the response variables were evaluated using a response surface methodology. Some physicochemical characteristics were also determined on pyrodextrins. Both factors negatively affected the AS content, although positively influenced the ΔE (P < 0.05). The yellow pyrodextrin produced with 1.82 g/kg and heating for 307 min, presented physicochemical properties similar to the commercial pyrodextrins from potato starch, with 46.6 % of AS, 24.5 of ΔE, high solubility and very low viscosity. The pyrodextrinization caused a decrease of 30 - 54 % in AS content (P < 0.05), making these yam pyrodextrins a promising material for water-soluble and very low viscous dietary fiber.

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El Instituto Nacional de Higiene "Rafael Rangel" (INHRR) inició las actividades académicas de la Especialización en Vigilancia Sanitaria de Medicamentos en septiembre de 2007. En los primeros ocho años de actividad, el Instituto ha concluido tres cohortes de especialistas. El objetivo del presente trabajo fue presentar una descripción de los especialistas graduados en el INHRR, los tutores y los trabajos especiales de grado (TEG) en el área de vigilancia sanitaria de medicamentos durante el periodo 2007 ­ 2014. Para ello, se realizó una investigación documental y de tipo descriptiva, revisando los expedientes resguardados en los archivos de la Coordinación de Postgrado de la Gerencia de Docencia e Investigación del INHRR. Con este programa de postgrado, el Instituto graduó a 27 especialistas en vigilancia sanitaria de medicamentos con un elevado índice académico (17,1 puntos). La mayoría de los egresados de la especialización fueron mujeres farmacéuticas egresadas de la Universidad Central de Venezuela, quienes laboraban en entes públicos al momento de iniciar el programa. El 70% de los TEG defendidos se realizaron dentro de dos de las líneas de investigación que lleva adelante la Gerencia Sectorial de Registro y Control del INHRR, a saber: las buenas prácticas regulatorias y la farmacovigilancia. Catorce profesionales fueron los encargados de dirigir los TEG, bajo la figura de tutor: dos se destacaron por haber dirigido el 44% de los TEG y otros dos por ser egresados de la especialización. Solo el 29% de los tutores fueron externos al Instituto

The National Institute of Hygiene "Rafael Rangel" (INHRR) began the academic activities of the Drug Sanitary Vigilance Specialization in September 2007. In the first eight years, the Institute has graduated three cohorts of specialists. The aim of this work was to present a description of the specialists graduated in the INHRR, their advisors and degree theses (DT) in the field of drug sanitary vigilance, during the period 2007 ­ 2014. Documentary and descriptive research were carried out; reviewing the records kept in the Postgraduate Coordination archives of the Management for Teaching and Research, INHRR. With this program, the Institute graduated 27 specialists in drug sanitary vigilance with a high academic score (17.1 points). Most of the specialists were female pharmacists graduated from the Central University of Venezuela, who worked in public entities when the program began. Seventy percent of the PT was conducted in two of the research lines carried out by the Management of Control and Registry, INHRR, namely: good regulatory practices and pharmacovigilance. Fourteen professionals supervised the PT, under the figure of tutor. Two tutors excelled for supervising 44% of the PT and another two tutors for being graduates of the specialization. Only 29% of the tutors were external to the Institute

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El Instituto Nacional de Higiene "Rafael Rangel" (INHRR) inició las actividades académicas de la Especialización en Micología Médica en septiembre de 2007. En los primeros ocho años de actividad, el Instituto ha concluido cuatro cohortes de especialistas. El objetivo del presente trabajo fue presentar una descripción de los especialistas graduados en el INHRR, los tutores y los trabajos especiales de grado (TEG) en el área de micología médica durante el periodo 2007 ­ 2014. Para ello, se realizó una investigación documental y de tipo descriptiva, revisando los expedientes resguardados en los archivos de la Coordinación de Postgrado de la Gerencia de Docencia e Investigación del INHRR. Con este programa de postgrado, el Instituto graduó a 23 especialistas en micología médica con un elevado índice académico (17,5 puntos). La mayoría de los egresados de la especialización fueron mujeres bioanalistas egresadas de la Universidad Central de Venezuela, quienes laboraban en entes públicos al momento de iniciar el programa. El 61% de los TEG defendidos se realizaron dentro de dos de las líneas de investigación que lleva adelante el Departamento de Micología Médica del INHRR, a saber: las micosis en pacientes inmunocompetentes e inmunocomprometidos utilizando el diagnóstico convencional y la resistencia antifúngica de hongos levaduriformes. Ocho profesionales fueron los encargados de dirigir los TEG, bajo la figura de tutor: dos se destacaron por haber dirigido el 52% de los TEG y tres por ser egresados de la especialización. Solo el 38% de los tutores fueron externos al Instituto

The National Institute of Hygiene "Rafael Rangel" (INHRR) began the academic activities of the Medical Mycology Specialization in September 2007. In the first eight years, the Institute has graduated four cohorts of specialists. The aim of this work was to present a description of the specialists graduated in the INHRR, their advisors and degree theses (DT) in the field of medical mycology, during the period 2007 ­ 2014. Documentary and descriptive research were carried out; reviewing the records kept in the Postgraduate Coordination archives of the Management for Teaching and Research, INHRR. With this program, the Institute graduated 23 specialists in medical mycology with a high academic score (17.5 points). Most of the specialists were bioanalyst women graduated from the Central University of Venezuela, who worked in public entities at the beginning of the program. Sixty-one percent of the DT was conducted in two of the research lines carried out by the Department of Medical Mycology, INHRR, namely: mycoses in immunocompetent and immunocompromised patients using conventional diagnosis and antifungal resistance of yeast infections. Eight professionals supervised the DT, under the figure of tutor. Two tutors excelled for supervising 52% of the DT and three tutors for being graduates of the specialization. Only 38% of the tutors were external to the Institute

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Digestibility of arracacha, cassava, cush-cush yam, potato and taro starches was evaluated. In vitro (potentially-available starch and total resistant starch) and in vivo digestibility in the rice weevil (Sitophilus oryzae) bioassay (survival, weight variation, α-amylase like activity [ALA], and uric acid excretion [UAE] as biomarkers) were estimated. In in vitro assays, all starches presented high resistant starch content (14-56%, dry basis), except for cassava starch. In in vivo assays, cush-cush yam and potato starches promoted higher ALA (>3 times) and UAE (>4 times) compare to a reference diet (cornstarch), in agreement to their low digestibility. These two biomarkers were related with resistant starch (r>0.81) and could be used to predict the starch bioavailability. This study demonstrates that the use of both in vitro and in vivo assays allows a better evaluation of starch digestibility, and may help to elucidate the final metabolic fate of starch digestion products.

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“La seguridad alimentaria en Venezuela” fue el tema central de la tercera edición del simposio organizado por el Grupo de Trabajo sobre Transición Alimentaria y Nutricional de la Fundación Bengoa para la alimentación y nutrición. En esta ocasión realizado dentro de las VI Jornadas de Investigación del Instituto de Biología Experimental (UCV) y la LXIV Convención Anual de la AsoVAC en Caracas, y enmarcado en las celebraciones del 2014 como Año Internacional de la Agricultura Familiar y el centenario del germano-venezolano Werner G. Jaffé, uno de los pioneros de la nutrición en Venezuela con talla internacional. Seis expertos se dieron cita para disertar sobre igual número de temas: la contribución de este ilustre bioquímico a la ciencia venezolana; los abordajes emergentes en la comprensión de la seguridad alimentaria; las voces de la inseguridad alimentaria y el hambre en el país; la importancia de la fortificación con ácido fólico en Venezuela; los programas de subsidio de alimentos, ¿dependencia o alimentación?; y los alimentos, la memoria y la convivencia desde un punto de vista socioantropológico. Tres aportes destacaron de la dilatada trayectoria de este insigne maestro y catedrático de varias generaciones: la vigencia del tema de la complementación proteica, la necesidad de rescatar el “Lactovisoy” para uso en programas alimentarios dirigidos a la población infantil y la impostergable tarea de buscar un alimento de consumo masivo que sirva de vehículo para la fortificación con ácido fólico, dirigido a la mujer venezolana, en especial, a las adolescentes(AU)

Food security in Venezuela” was the central theme of the third symposium on nutrition organized by the Working Group on Nutrition Transition of the Bengoa Foundation for Food and Nutrition. It was held in the Sixth Research Conference of the Institute of Experimental Biology (UCV) and the 64th AsoVAC Annual Convention, and framed in the celebrations of the 2014 International Year of Family Farming and the centenary of the German-Venezuelan Werner G. Jaffe, one of the pioneers of nutritional biochemistry in Venezuela with international stature. Six experts gathered to speak on equal number of themes: the important contribution of this famous biochemist to the Venezuelan science; emerging approaches in understanding food security; the voices of food insecurity and hunger in the country; the importance of folic acid fortification in Venezuela; subsidy programs of foods - nourishment or dependency?; and food, memory and co-existence from a socio-anthropological point of view. Three issues were highlighted from the legacy of Dr Jaffe: the issue of protein complementation, the use of the instant drink “Lactovisoy” in food programs for the children, and the urgent task of searching for a well consumed food to be fortified with folic acid, to target Venezuelan women, especially adolescents(AU)

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En marzo del año 2005, la Fundación Bengoa comprometió a diversos profesionales para asumir los retos de la alimentación y nutrición del país. Así, el 11 de julio de 2005, se realizó la reunión fundacional del grupo de trabajo sobre Transición Alimentaria y Nutricional (grupo TAN) con la presencia de Mercedes López de Blanco, Melania Izquierdo y Alexander Laurentin. El Grupo TAN es un espacio de encuentro interdisciplinario e interinstitucional, que sirve para la reflexión y la discusión de ideas, con la finalidad de identificar e instrumentar estrategias relacionadas con la transición alimentaria y nutricional. En Venezuela esta transición ha ocasionado una doble carga, debido a la superposición del sobrepeso con la desnutrición. Se decidió enfrentar la carga del sobrepeso. La primera actividad fue un foro realizado en noviembre de 2005, donde se detectó que grupos de investigación del país, usan diferentes criterios y valores límite para identificar los factores de riesgo y diagnosticar las enfermedades relacionadas con la nutrición, particularmente en niños, niñas y adolescentes. El grupo, con el enfoque investigación acción, enfrentó este problema: una encuesta electrónica detectó variabilidad en la utilización de las referencias, inconsistencia entre la referencia y las variables utilizadas, y un déficit en la evaluación de los hábitos de vida; por lo que se diseñó un taller de actualización (que incluye un caso clínico). Esta actividad ha beneficiado a más de un centenar de pediatras venezolanos y ha formado una decena de facilitadores en varias regiones del país(AU)

In March 2005, the Bengoa Foundation committed a number of professionals to the challenge of food and nutritional issues in Venezuela. On July 11th 2005, the founding meeting of the TAN group (short for “Nutrition Transition Task Group”) took place with the presence of Mercedes López de Blanco, Melania Izquierdo and Alexander Laurentin. The TAN group is an interdisciplinary and inter institutional group that debates and discusses ideas, in order to identify and develop strategies on nutrition transition. In Venezuela, this transition has resulted in the double burden of malnutrition, as overweight coexists with under nutrition. The task group decided to address the overweight problem. The first activity was a forum held on November 2005, where it was detected that various research groups in Venezuela use different criteria and cut-off limits to identify risk factors and diagnose diseases related to nutrition, particularly in children and adolescents. The TAN group, with an action research approach, addressed this problem: An electronic survey detected variability in the use of the references, inconsistencies between a particular reference and the variables used, and a deficit on lifestyle evaluation; therefore, a workshop was designed (using a clinical case). This activity has benefited a hundred of Venezuelan pediatricians and trained ten facilitators across the country(AU)

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El análisis de componentes principales (PCA), escalamiento multidimensional no-métrico (MDS) y el análisis de similaridad (ANOSIM) son técnicas estadísticas multivariadas, las dos primeras representan gráficamente de manera simultánea las unidades estadísticas y las variables que las caracterizan, evaluando similaridades entre las unidades y correlaciones entre las variables, la última técnica dota de un test estadístico no paramétrico para comparar agrupaciones de las unidades. Este trabajo evaluó la aplicabilidad de estas técnicas para valorar la calidad nutricional de la dieta, utilizando el bioensayo del gorgojo de arroz. Las dietas ensayadas fueron: almidón de maíz; almidón de papa; 5% glucosa; arvejas; ayuno y ayuno con agua. Se estudiaron las variables supervivencia, variación de peso y composición corporal. El PCA y MDS mostraron relaciones positivas de la supervivencia y variación de peso con los parámetros corporales grasa y carbohidratos, siendo mayor para dietas de almidón, similares al control positivo. En el PCA se observaron diferencias en las poblaciones mantenidas con las diferentes dietas; el MDS no distingue claramente entre ellas, aún cuando logra diferenciar la dieta definida por el ayuno de las restantes. Ambos estudios definieron un gradiente del valor nutritivo de las dietas, en el eje de las abscisas. El ANOSIM indicó diferencias significativas (p<0,05) entre grupos de insectos sustentados con estas dietas. Esta prueba refuerza los resultados obtenidos en el PCA y MDS. La aplicación de estas herramientas estadísticas son promisorias para analizar procesos complejos, como la interacción de distintas variables que midan la calidad nutricional de diferentes dietas.

The principal component analysis (PCA), non-metric multidimensional scaling (MDS) and analysis of similarity (ANOSIM) are multivariate statistical techniques that graphically represent numerical measures of several factors and display multiple relationships that may exist between them. In this study, we evaluated the applicability of these techniques to analyze the nutritional quality of diet, using as model, the bioassay rice weevil. The diets tested were: corn starch, potato starch, 5% glucose, peas, starved and starved with water supply. The variables studied were: survival, weight change and body composition. The PCA and MDS showed positive relationships of survival and weight change with body fat and carbohydrate parameters. Fat and carbohydrates were greater in starches diets, similar to the positive control. The PCA showed differences between populations fed with different diets, whereas the MDS showed similarity between diets. Both studies defined a gradient of the nutritive value of diets in the x-axis. The ANOSIM indicate significant (p<0, 05) differences between groups. This test is necessary to support the results obtained in the PCA and MDS. The application of these statistical tools is promising to analyze complex processes such as interaction of differents variables to measure the nutritional quality of diets.

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The principal component analysis (PCA), non-metric multidimensional scaling (MDS) and analysis of similarity (ANOSIM) are multivariate statistical techniques that graphically represent numerical measures of several factors and display multiple relationships that may exist between them. In this study, we evaluated the applicability of these techniques to analyze the nutritional quality of diet, using as model, the bioassay rice weevil. The diets tested were: corn starch, potato starch, 5% glucose, peas, starved and starved with water supply. The variables studied were: survival, weight change and body composition. The PCA and MDS showed positive relationships of survival and weight change with body fat and carbohydrate parameters. Fat and carbohydrates were greater in starches diets, similar to the positive control. The PCA showed differences between populations fed with different diets, whereas the MDS showed similarity between diets. Both studies defined a gradient of the nutritive value of diets in the x-axis. The ANOSIM indicate significant (p < 0.05) differences between groups. This test is necessary to support the results obtained in the PCA and MDS. The application of these statistical tools is promising to analyze complex processes such as interaction of differents variables to measure the nutritional quality of diets.

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BACKGROUND: Pyrodextrins, modified starches produced by heat/acid treatment, have been used extensively in the paper industry. Recently, pyrodextrinisation has been recognised as a way of producing a "resistant starch" that is water-soluble and has non-starch linkages. However, a full characterisation of the fermentation properties of pyrodextrins has not been reported. AIM OF THE STUDY: To evaluate the effect of pyrodextrinisation on the fermentation characteristics of starches, prepared from Venezuelan crops, in a simple in vitro model of the human colon. METHODS: Potato, lentil and cocoyam pyrodextrins were produced using heat (140 degrees C for 3 h) and hydrochloric acid as catalyst (1.82 g/kg starch). Then, both native and modified starches were pre-digested with pepsin and pancreatic enzymes and their resistant components fermented anaerobically using human faeces as inocula for 24 h. Short-chain fatty acids (SCFA), pH, residual starch and carbohydrate in the cultures were measured. RESULTS: More than 69% of initial carbohydrate disappeared from both pre-digested native and pyroconverted starch cultures. More than 6.8 and 10.0 mmol net SCFA per gram carbohydrate were produced from pre-digested native and pyrodextrinised starches, respectively. In cultures of predigested pyrodextrins, the molar ratio for propionate doubled, whereas the ratio of acetate decreased by 25% when compared with pre-digested native starches. The ratio of butyrate did not change. CONCLUSIONS: The mechanism for the change in SCFA profile is unclear, but may be related to solubility and/or presence of nonstarch linkages. The presence of these bonds may modify the accessibility/affinity of bacterial enzymes to the modified starch structure.

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Starch-modifying processes, such as pyrodextrinization, are potential ways to alter the nutritional features of this polysaccharide. A widely used method for pyrodextrinizing maize starch was also applied to lentil, sorghum, cocoyam, sagu, and cassava starches, and the in vitro digestibility of the products was evaluated. Pyrodextrins were produced by heating starch at 140 degrees C for 3 h, with catalytic amounts of HCl. The enzymatically available starch content of all preparations decreased by 55-65% after modification. Thus, pyrodextrinization seems to be an effective way to produce indigestible glucans from different starches. Pyrodextrins obtained were complex mixtures of starch derivatives with a wide range of molecular weight as estimated by gel filtration chromatography. Both their molecular weight profiles and contents of indigestible fractions varied with starch source. Experiments with lentil and cassava starches showed that changing dextrinization conditions also affects the susceptibility to enzymatic hydrolysis of the product.

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The intracellular Ca2+ concentration in different trypanosomatids is about 50 nanomolar, which concentration in different trypanosomatids is about 50 nanomolar, which is 4 orders of magnitude lower than in the extracellular milieu. This fact implies the existence of well developed mechanisms for the maintenance of such a high calcium gradient. In higher eukaryotics a number of different structures have been implicated in this function. Some of them are located in intracellular organelles, and others in the plasma membrane. Since intracellular organelles are limited by their storage capacity, long-term Ca2+ homeostasis resides solely in the plasma membrane. In higher eukaryotics, a calcium pump or Ca(2+)-ATPase located in the plasma membrane, because of its high Ca2+ affinity, has been proposed as the structure responsible for the maintenance of the cytoplasmic Ca2+ concentration at the submicromolar level. The presence of a Ca(2+)-ATPase in trypanosomatids has been debated. While some groups have reported its absence, others have reported the existence of an enzyme which is Mg(2+)-independent or even inhibited by Mg2+. On the other hand, in none of these reports any correlation was shown between the Ca(2+)-ATPase activity observed and the Ca2+ transport function attributed to this enzyme. We have previously shown that a calmodulin-stimulated Mg(2+)-dependent Ca(2+)-ATPase is present in the plasma membrane of Leishmania braziliensis and of Trypanosoma cruzi. Plasma membrane vesicles from these parasites are able to accumulate Ca2+ in the presence of the ATP-Mg complex. The similarities found between the kinetics parameters and other properties of the Ca(2+)-ATPase and the Ca2+ transport activity strongly suggest a common molecular entity. The stoichiometry calculated from these parameters approaches the 1:1 stoichiometry for Ca2+ and ATP, as reported for the Ca2+ pump from higher eukaryotic cells. In this report we show that plasma membrane vesicles from Leishmania mexicana possess a Ca(2+)-ATPase with characteristics which are similar to that reported by us for other trypanosomatids. Thus, the enzyme has a high Ca2+ affinity which is further increased upon addition of calmodulin. The maximal velocity is also increased by calmodulin...

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