Evaluation and monitoring of the water quality of an Argentinian urban river applying multivariate statistics.

In this work, we present the water quality assessment of an urban river, the San Luis River, located in San Luis Province, Argentina. The San Luis River flows through two developing cities; hence, urban anthropic activities affect its water quality. The river was sampled spatially and temporally, evaluating ten physicochemical variables on each water sample. These data were used to calculate a Simplified Index of Water Quality in order to estimate river water quality and infer possible contamination sources. Data were statistically analyzed with the opensource software R, 4.1.0 version. Principal component analysis, cluster analysis, correlation matrices, and heatmap analysis were performed. Results indicated that water quality decreases in areas where anthropogenic activities take place. Robust inferential statistical analysis was performed, employing an alternative of multivariate analysis of variance (MANOVA), MANOVA.wide function. The most statistically relevant physicochemical variables associated with water quality decrease were used to develop a multiple linear regression model to estimate organic matter, reducing the variables necessary for continuous monitoring of the river and, hence, reducing costs. Given the limited information available in the region about the characteristics and recovery of this specific river category, the model developed is of vital importance since it can quickly detect anthropic alterations and contribute to the environmental management of the rivers. This model was also used to estimate organic matter at sites located in other similar rivers, obtaining satisfactory results.

Testosterone is closely related to Leydig cell activity, environmental factors, and androgen receptor distribution in adult male lizards of Liolaemus cuyanus (Reptilia: Liolaemidae) during the reproductive cycle.

Testosterone, the primary sex hormone in male lizards, is closely linked to Leydig cell activity (the cells where steroidogenesis occurs) throughout the reproductive cycle, but testosterone action is related to androgen receptors (ARs) distribution in the seminiferous epithelium. In temperate zones, environmental factors detected through the hypothalamic-pituitary-gonadal axis, downregulate plasma testosterone, resulting in a seasonal reproductive cycle. The aim of this work is to study plasma testosterone in adult male lizards of Liolaemus cuyanus, an oviparous species, throughout its reproductive cycle and its relationship with Leydig cell histology, TotalLeydigCell/ActiveLeydigCell (TLC/ALC) ratio, environmental factors (temperature, relative humidity and solar irradiation) and ARs distribution in seminiferous epithelium. Specimens (N = 27) were captured (October to March) in a semi-arid zone (Valle de Matagusanos, San Juan, Argentina) and grouped into three relevant reproductive periods: pre-reproductive (PrR), reproductive (R), and post-reproductive (PsR). Significant differences in plasma testosterone were found among these periods, highest during R than in PsR. A significant positive correlation between plasma testosterone and TLC/ALC ratio was also observed. Plasma testosterone has a significant positive correlation only with solar irradiation, but not with the other variables. In PrR and R, ARs distribution was cytoplasmic and nuclear, shifting to only cytoplasmic in PsR. These results highlight the close correspondence between plasma testosterone, Leydig cell histology and activity, environmental factors, and ARs distribution, resulting in a synchronization that allows males of L. cuyanus to coordinate their reproductive cycle with the most favorable environmental conditions, probably for mating and birth of offspring.

Evaluación preliminar de la callogénesis y organogénesis in vitro Leptochloa crinita (lag.) p. m. peterson & n. snow / Preliminary evaluation of in vitro callogenesis and organogenesis Leptochloa crinita (Lag.) P. M. Peterson & N. Snow

RESUMEN El cambio de uso de la tierra por diversos factores socio-económicos, climáticos, tecnológicos y culturales han tenido como consecuencia en la provincia de San Luis (Argentina) la pérdida de diversidad biológica, fragmentación y destrucción de hábitat, comprometiendo la existencia de la flora nativa, como es el caso de Leptochloa crinita (Lag.) P.M. Peterson & N. Snow, una especie con buena aptitud forrajera del monte chaqueño. Bajo este contexto, el presente trabajo tuvo como objetivo aplicar biotécnicas como alternativas para una propagación apropiada de este acervo genético. Se evaluó la organogénesis y callogénesis in vitro de diferentes explantos con distintos reguladores de crecimiento en un medio nutritivo Murashige y Skoog. El tratamiento con 6 mg l-1 de 2,4-D estimuló la callogénesis, mientras que los tratamientos combinados de auxinas y citocininas presentaron las mayores tasas de morfogénesis. El desarrollo de esta biotécnica permite disponer de metodologías adecuadas para iniciar ensayos de conservación in vitro, análisis de la variabilidad genética e inicio de programas de domesticación y mejoramiento genético.

ABSTRACT In San Luis (Argentina), land-use change due to a variety of socioeconomic, climatic, technological and cultural factors has caused the loss of biological diversity, fragmentation and habitat destruction, compromising the existence of native flora, such as in the case of Leptochloa crinita (Lag.) PM Peterson & N. Snow, a species with good forage aptitude from the Chaco forest. In this context, the present work aimed to apply biotechniques as an alternative for an appropriate propagation of this gene pool. In vitro organogenesis and callogenesis of several explants were evaluated with different growth regulators on a Murashige and Skoog nutrient medium. Treatment with 6 mg l-1 of 2,4-D stimulated callogenesis, while combined auxin and cytokinin treatments presented the highest rates of morphogenesis. The development of this biotechnique makes it possible to have adequate methodologies to initiate in vitro conservation trials, analysis of genetic variability and the initiation of domestication and breeding programs.

Niveles de hierro en sangre según adherencia a la dieta libre de gluten en niños celiacos de edad escolar / Blood iron levels in accordance with adherence to a gluten-free diet in celiac school aged children

Introducción: la enfermedad celiaca (EC) provoca atrofia intestinal, trastornos en la absorción de nutrientes y desnutrición progresiva. La deficiencia de hierro es una carencia nutricional muy prevalente. Una alimentación estricta libre de gluten (LG) permite calidad de vida. Objetivo: evaluar la situación nutricional del hierro de niños celiacos escolares mediante la determinación de parámetros bioquímicos, su relación con el consumo del mineral y la adherencia a la dieta LG en San Luis. Métodos: estudio observacional, analítico y transversal. Fueron incluidos 44 niños con EC, de seis a diez años de edad, con diagnóstico de celiaquía y registrados en entidades públicas y privadas de San Luis (Argentina) durante 2011-2012. Mediante una encuesta cuali-cuantitativa se determinaron hábitos alimentarios y características sociodemográficas. Se evaluaron niveles de hierro y adherencia a una dieta LG. Se construyeron modelos de regresión lineal generalizados para verificar la asociación de ferritina con el consumo de hierro y adherencia a la dieta. Resultados: la mayoría de las familias tenían nivel socioeconómico bajo y eran numerosas. La alimentación no previno la anemia ferropénica según biodisponibilidad. La mayoría de los niños presentaron un estado inmunológico, anticuerpos antiendomisio y antitransglutaminas normales. El 7% presentó bajos niveles de hierro. La ferritina en condiciones de consumo adecuado de hierro se relacionó con los anticuerpos predictores y la presencia de ambos padres en el hogar. Conclusión: en condiciones de consumo adecuado de hierro, sus niveles en sangre se relacionan con adherencia al tratamiento libre de gluten (AU)

Introduction: Celiac disease (CD) causes intestinal damage, inability to absorb nutrients, and progressive malnutrition. Iron deficiency is one of the predominant nutritional problems. A strict gluten-free diet (GF) allows for an optimal quality of life. Objective: To assess the nutritional situation of iron in school-aged celiac children by determining biochemical parameters, their relation to the consumption of the mineral and adherence to gluten-free diets in San Luis. Methods: Observational, analytical and cross-sectional study. We included 44 children with CD, from 6-10 years of age, with diagnosis of celiac disease and registered in public and private entities of San Luis (Argentina) during 2011-2012. A qualitative-quantitative survey was used to determine dietary habits and sociodemographic characteristics. Iron levels and adherence to a GF diet were evaluated. Generalized linear regression models were constructed to verify the association of ferritin with iron consumption and adherence to diet. Results: Most families had low socioeconomic status and were large families. Current feeding did not prevent iron deficiency anemia. Most children had normal immune system, and normal antiendomysial and antitransglutaminase antibodies; 7% of the children showed low levels of iron. Under adequate iron consumption conditions, ferritin was associated to predictor antibodies and the presence of both parents in the home. Conclusion: Under adequate conditions of iron consumption, the levels of iron in blood were related to adherence to gluten-free diets (AU)

Blood iron levels in accordance with adherence to a gluten-free diet in celiac school aged children.

INTRODUCTION: Celiac disease (CD) causes intestinal damage, inability to absorb nutrients, and progressive malnutrition. Iron deficiency is one of the predominant nutritional problems. A strict gluten-free diet (GF) allows for an optimal quality of life. OBJECTIVE: To assess the nutritional situation of iron in school-aged celiac children by determining biochemical parameters, their relation to the consumption of the mineral and adherence to gluten-free diets in San Luis. METHODS: Observational, analytical and cross-sectional study. We included 44 children with CD, from 6-10 years of age, with diagnosis of celiac disease and registered in public and private entities of San Luis (Argentina) during 2011-2012. A qualitative-quantitative survey was used to determine dietary habits and sociodemographic characteristics. Iron levels and adherence to a GF diet were evaluated. Generalized linear regression models were constructed to verify the association of ferritin with iron consumption and adherence to diet. RESULTS: Most families had low socioeconomic status and were large families. Current feeding did not prevent iron deficiency anemia. Most children had normal immune system, and normal antiendomysial and antitransglutaminase antibodies; 7% of the children showed low levels of iron. Under adequate iron consumption conditions, ferritin was associated to predictor antibodies and the presence of both parents in the home. CONCLUSION: Under adequate conditions of iron consumption, the levels of iron in blood were related to adherence to gluten-free diets.

INTRODUCCIÓN: la enfermedad celiaca (EC) provoca atrofia intestinal, trastornos en la absorción de nutrientes y desnutrición progresiva. La deficiencia de hierro es una carencia nutricional muy prevalente. Una alimentación estricta libre de gluten (LG) permite calidad de vida. OBJETIVO: evaluar la situación nutricional del hierro de niños celiacos escolares mediante la determinación de parámetros bioquímicos, su relación con el consumo del mineral y la adherencia a la dieta LG en San Luis. MÉTODOS: estudio observacional, analítico y transversal. Fueron incluidos 44 niños con EC, de seis a diez años de edad, con diagnóstico de celiaquía y registrados en entidades públicas y privadas de San Luis (Argentina) durante 2011-2012. Mediante una encuesta cuali-cuantitativa se determinaron hábitos alimentarios y características sociodemográficas. Se evaluaron niveles de hierro y adherencia a una dieta LG. Se construyeron modelos de regresión lineal generalizados para verificar la asociación de ferritina con el consumo de hierro y adherencia a la dieta. RESULTADOS: la mayoría de las familias tenían nivel socioeconómico bajo y eran numerosas. La alimentación no previno la anemia ferropénica según biodisponibilidad. La mayoría de los niños presentaron un estado inmunológico, anticuerpos antiendomisio y antitransglutaminas normales. El 7% presentó bajos niveles de hierro. La ferritina en condiciones de consumo adecuado de hierro se relacionó con los anticuerpos predictores y la presencia de ambos padres en el hogar. CONCLUSIÓN: en condiciones de consumo adecuado de hierro, sus niveles en sangre se relacionan con adherencia al tratamiento libre de gluten.