Towards an ethical and legal framework in archeogenomics: A local case in the Atlantic coast of central Patagonia.

Ethical discussions around ancient DNA (aDNA) research predate the technological breakthroughs that led to the accelerated generation of ancient genomic data, revealing a long-due need to address these aspects in the field. Given the diverse conflicts that genomics has raised towards the communities associated with the Non-living Human Ancestors under study, it has been suggested that the ethical and legal implications of genetically studying present-day and ancient human populations should be considered case-by-case. Nevertheless, the discussions have focused on US and European perspectives. To contribute from a local and Latin American position to the problem, we present the history of consensus and disagreement of the relationships between scientists and Indigenous communities of the Atlantic coast of the central Argentinian Patagonia. We describe how these relationships resulted in the approval of a groundbreaking provincial law that acknowledges the Indigenous community's right to be involved in decision-making concerning their Ancestors. In addition, we emphasize how these established relationships allowed the development of aDNA studies. With this background, we address the main ethical concerns of genomic studies of Ancestors identified in the reference literature and commit to applying some of the recommendations suggested in those ethical guidelines. Then, we reflect on possible negative consequences of ongoing research and propose some suggestions based on personal experiences that will contribute to moving the ethical field towards a more contextualized science with a local perspective.

Comparison of frame index reference percentiles in Argentine and European boys and girls.

INTRODUCTION: The frame index (FI), based on measurements of elbow breadth and height, is the body frame size parameter most frequently used in child and adolescent populations to assess skeletal robustness. In 2018, the first FI reference percentiles were elaborated with data of boys and girls aged 0-18 years from different European populations. In Argentina, the FI reference values were published in 2022. OBJECTIVE: The present study aims to compare the Argentine (AR) and European (EU) FI reference percentiles to evaluate possible variation in bone robustness between populations. METHODS: The values of the 3rd, 50th and 97th percentiles of the AR and EU FI references for boys and girls aged 4-14 years were compared using the Wilcoxon test (p < .05). Percentage differences between means (PDM) were calculated to analyze the magnitude of the differences between both references. The R 3.2.0 program was used to plot the percentile curves. RESULTS: The FI reference values were lower in AR than in EU in both the 3rd and the 50th percentiles, regardless of sex and age. Conversely, the AR reference values of the 97th percentile were higher than the EU values at most ages. CONCLUSIONS: The comparison of the AR and EU FI references showed similar age and sex growth patterns. However, differences in percentile values between populations were observed, highlighting the importance of having local references for the evaluation of skeletal robustness.

Referencias de índice de masa corporal. Precisión diagnóstica con área grasa braquial en escolares argentinos / Body mass index references. Diagnostic accuracy with the upper-arm fat area in Argentine schoolchildren

El índice de masa corporal (IMC) es una eficaz herramienta para detectar la sobrecarga ponderal en niños y adolescentes, asociado a la adiposidad corporal. Objetivo. Analizar la concordancia, sensibilidad y especificidad de tres referencias internacionales de IMC/edad (OMS, IOTF y CDC) para diagnosticar el exceso ponderal y conocer su precisión diagnóstica para identificar el exceso de adiposidad con relación al área grasa braquial (AGB) en población infanto juvenil de Argentina. Materiales y métodos. Se realizó un estudio multicéntrico, descriptivo-comparativo y transversal entre 2003 y 2008, en 22.658 niños y adolescentes argentinos de 4 a 13 años de edad. A partir del peso, talla, circunferencia del brazo y pliegue tricipital, se calcularon IMC y AGB. Se analizó la concordancia, sensibilidad y especificidad de referencias de IMC/edad (OMS, CDC, IOTF) y la precisión diagnóstica (curvas ROC) para identificar exceso de adiposidad, a partir del AGB, así como el punto de corte óptimo (PCO). Resultados. Las tres referencias tuvieron buena concordancia. La mayor sensibilidad correspondió a OMS y la mayor especificidad a IOTF. El área bajo la curva (ABC) fue mayor en Z-IMC/IOTF en varones y en Z-IMC/OMS en mujeres. Los PCO mostraron discrepancias, siendo mayores con OMS. Conclusión. Las tres referencias muestran similar precisión diagnóstica para detectar alta reserva calórica, con puntos de corte óptimo para las puntuaciones Z-IMC menores a 2 Z scores. Esto resulta relevante para la identificación de exceso de adiposidad en poblaciones, en relación con la implementación de políticas públicas de prevención de enfermedades crónicas no transmisibles(AU)

The body mass index (BMI) is an effective tool to detect weight overload in children and adolescents, associated with body adiposity. Objective. To analyze the concordance, sensitivity and specificity of three international BMI/age references (WHO, IOTF and CDC) to diagnose excess weight and to know their diagnostic accuracy to identify excess adiposity in relation to the brachial fat area (BFA) in Argentine child-youth population. Materials and methods. A multicenter, descriptive- comparative and cross-sectional study was carried out between 2003 and 2008 in 22.658 Argentine children and adolescents between aged 4 to 13 years. From the weight, height, arm circumference and tricipital fold, BMI and BFA were calculated. The concordance, sensitivity, and specificity of BMI / age references (WHO, IOTF, CDC,) were analyzed and the diagnostic precision (ROC curves) to identify excess adiposity, from the BFA, as well as the optimal cut-off point (OCP). Results. The three references had good agreement, the highest sensitivity corresponded to WHO and the highest specificity to IOTF. The area under the curve (AUC) was greater in Z-BMI/IOTF in men and in Z-BMI/WHO in women. The OCPs showed discrepancies, being higher with WHO. Conclusion. The three references show similar diagnostic accuracy to detect high caloric reserve, but with cut-off points for Z-BMI scores less than 2 Z scores. This is relevant for the identification of excess adiposity in populations in relation to the implementation of public policies for the prevention of chronic non-communicable diseases(AU)

Dimorfismo sexual del crecimiento y de la composición corporal en la población infanto-juvenil de Puerto Madryn (Chubut, Argentina) / Sexual dimorphism of growth and body composition in the child-youth population of Puerto Madryn (Chubut, Argentina)

Introducción: Analizar la composición corporal es fundamental en la valoración del estado nutricional del individuo. Consiste en cuantificar los componentes corporales y su variabilidad durante el crecimiento y entre sexos. Considerando el vacío de información en esta temática, el objetivo del presente trabajo fue analizar el dimorfismo sexual de la composición corporal durante el crecimiento en función del estado nutricional evaluado a través del índice de masa corporal en una muestra de escolares argentinos. Material y métodos: Se realizó un estudio antropométrico transversal, con varones y mujeres, de entre 6-14 años, asistentes a escuelas de Puerto Madryn. El estado nutricional se determinó según la IOTF, diferenciando delgadez, sobrepeso, obesidad y normonutrición. En cuanto a la composición corporal, se analizó la distribución adiposa, las masas grasa y libre de grasa y del índice de robustez esquelética. Se realizaron comparaciones gráficas empleando diferencias porcentuales entre medias (DPM%).para analizar variaciones en el crecimiento y la composición corporal de los malnutridos. Resultados: La muestra incluyó 2732 escolares (56,5%presentaba normonutrición, 2,9% delgadez, 26,0% sobrepeso y 14,6% obesidad). En base a la edad decimal cada participante fue asignado al grupo etario de prepúberes (48,4%) y púberes (51,6%). El análisis del dimorfismo sexual mostró diferencias significativas entre sexos en prepúberes normonutridos, con sobrepeso y obesos, mientras que entre los púberes éstas se hallaron en todos los casos. Las DPM% fueron positivas para normonutridos-delgados; en tanto que para normonutridos-sobrepeso y normonutridos-obesos fueron negativas. (AU)

Introduction: Analysis of body composition is essential in assessing nutritional status of the individual. It consists of quantifying the body components and their variability during growth and between sexes. Considering the lack information on this topic, the objective of this work was to analyzed the sexual dimorphism of body composition during growth as a function of the nutritional sta-tus evaluated through the body mass index in a sample of Argentinean school children. Material and methods: A cross-sectional anthropometric study was carried out, with males and females, aged 6-14 years, attending schools in Puerto Madryn. Nutritional status was determined according to the IOTF, differentiating thinness, overweight, obesity and normonutrition. Regarding body composition, adipose distribution, fat and fat-free masses and Frame Index were analyzed. Graphical comparisons were made using percentage differences between means (PDM%) to analyze variations in growth and body composition of the malnourished. Results: The sample included 2732 schoolchildren (56.5% presented normal nutrition, 2.9% thinness, 26.0% overweight and 14.6% obesity). Based on decimal age, each participant was assigned to prepubertal (48.4%) and pubertal (51.6%) age group. Analysis of sexual dimorphism showed significant differences between sexes in normalnourished, overweight and obese prepubescent, while these were found in all cases among pubertal subjects. PDM% were positive for normalnourished-thin; while for normalnourished-overweight and normalnourished-obese they were negative. (AU)

Parásitos intestinales en poblaciones infantojuveniles; ambiente y comportamiento social / Prevalence of intestinal parasites in child and youth populations; environment and social behavior

Introduction: The decreasing prevalence of parasitosis from north to south in Argentina has led the scientific community to focus the epidemiological studies on the most vulnerable areas and, consequently, neglect the populations of Patagonia (South Argentina). The objectives of the present study were (i) to determine the prevalence of intestinal parasites in children and youth of Puerto Madryn (Chubut province, Patagonia), and (ii) to evaluate the parasitic infections found concerning socio-environmental factors and hygiene practices of the population. Materials and methods: Serial stool samples were processed using modified Ritchie and FLOTAC dual pellet techniques, and samples of anal swabs were examined by sedimentation. Socio-environmental variables and hygiene practices of the participants were surveyed using a semi-structured questionnaire. Results: Of all examined participants, 39.1% (68/174) were parasitized. A total of 6 parasite species were found and the most prevalent were Blastocystis sp (19.0%), Enterobius vermicularis (17.8%), and Giardia lamblia (6.3%). The risk of parasitosis and infection for Blastocystis sp was greater in participants who lived in houses without piped water (OR = 2.9 and OR = 3.2, respectively). The risk of infection for G. lamblia was positively associated with the lack of public waste collection service (OR = 5.6). Infection for E. vermicularis was higher in participants whose parents had a basic level of education (OR = 5.0). Conclusion: The parasitic infections observed reflect the environmental conditions of Patagonia and the need to focus studies on populations from peripheral areas to urban centers that are exposed to greater socio-economic vulnerability.

Introducción: La prevalencia de parasitosis decreciente de norte a sur en la Argentina, ha llevado a la comunidad científica a enfocar sus estudios epidemiológicos hacia las zonas más vulnerables y desatender a las poblaciones de la Patagonia (sur de Argentina). Los objetivos del presente estudio fueron: determinar la prevalencia de parásitos intestinales en niños y jóvenes de Puerto Madryn (Chubut, Patagonia), y evaluar las infecciones parasitarias en relación con los factores socioambientales y las prácticas de higiene de la población. Materiales y métodos: Se procesaron muestras seriadas de materia fecal mediante las técnicas Ritchie modificada y FLOTAC dual pellet, y muestras de escobillado anal por sedimentación. Se relevaron las variables socioambientales y las prácticas de higiene de los participantes mediante cuestionarios semiestructurados. Resultados: El 39.1% (68/174) de la población analizada estuvo parasitado. Se halló un total de 6 especies parásitas, las más prevalentes de las cuales fueron Blastocystis sp (19.0%), Enterobius vermicularis (17.8%) y Giardia lamblia (6.3%). El riesgo de parasitosis y de infección por Blastocystis sp fue mayor en los participantes que no poseían agua de red (odds ratio [OR] = 2.9 y OR = 3.2, respectivamente). La infección por G. lamblia se asoció de manera positiva con la falta de recolección pública de residuos (OR = 5.6). La infección por E. vermicularis fue superior en los participantes con padres que tenían un nivel de estudios primario (OR = 5.0). Conclusión: Las infecciones parasitarias observadas reflejan las condiciones ambientales de la Patagonia y la necesidad de orientar los estudios a poblaciones periféricas de los centros urbanos, las cuales están expuestas a mayor vulnerabilidad socioeconómica

Decrease of external skeletal robustness (Frame Index) between two cohorts of school children living in Puerto Madryn, Argentina at the beginning of the 21st century.

Background: It has been shown that modern life style with reduced physical activity can lead to lower bone accumulation. Also a decline trend in external skeletal robustness in children and young adolescents, measured by the Frame Index (FI), seems to have a parallel trend with the increase in overweight and obesity. Based on these findings we estimate that likely, the FI should be changed after a decade in the Argentinean population as well as in others population of the world. Thereby, the aim of the present study was to describe, using the FI, the pattern of external skeletal robustness in school children aged 6-14 years from two cohorts of Argentina (Puerto Madryn, Chubut) and to compare them with the European reference (Czech Republic, Germany, Poland and Russia). Methods: Elbow breadth and height of Puerto Madryn school children were collected in two cross-sectional studies conducted between 2001-2006 (cohort 1 = C1) and 2014-2016 (cohort 2 = C2). Percentiles (P) values, for males and females, from C1 and C2 were calculated combining the LMS-method and its extension. A t-test has been used to compare, by age and sex, the FI values between the Argentinean cohorts and the European reference (ER). Then, in order to know the percentage of the variation of the percentiles values between cohorts, as well as with ER, percent differences between means (PDM%) were employed. Results: FI from Argentinean cohorts differed significantly from ER. Even more, C2 was not only smaller than ER, but also than C1. In males, C1-C2 showed significant differences at 6-8, 11 and 12 years and in females at all ages. Then, respect to ER each Argentinean cohort showed significant differences in males of C1 at 6, 12-14 years and in females at 6 and 11-14 years; and of C2, in both sexes, from 6 to 14 years. The PDM% values for elbow breadth of male were negative in ER-C1 in all percentiles analyzed; in ER-C2 positive (P3 and P50) and negative (P97) and C1-C2 recorded positive values. In females, elbow breadth showed negative values for ER-C1 (P50 and P97), and positive for the remaining values. Finally, height registered, in both sexes, negative values in ER-C1 (except P97 in females), ER-C2 and C1-C2. Conclusions: After ten years of the first study carried on in Puerto Madryn, school children show a negative trend in the external skeletal robustness. Additionally, the children of both Argentinean cohorts have lower values compared to the European reference, and mainly the actual cohort. This situation would be explained, in part, by the progressive increase over time of overweight and obesity as consequence, among others, of the change in the quantity and/or quality of the food that children have access to and with the physical activity they do at school and outside.

Percentilos de referencia de la circunferencia y de las áreas muscular y grasa del brazo para la población infantojuvenil argentina (4-14 años) / Reference percentiles for mid-upper arm circumference, upper arm muscle and fat areas in the Argentine child and adolescent population (4-14 years old)

Introducción: La circunferencia del brazo (CB) se reconoce como buen indicador del estado nutricional. Objetivo: Estimar los percentilos de referencia para la CB y las áreas muscular (AM) y grasa (AG) del brazo en la población infantojuvenil argentina mediante el empleo del método LMS (lambda, mu, sigma, en inglés). Materiales y métodos: La muestra estuvo constituida por escolares de 4,0 a 13,9 años residentes en Jujuy, Catamarca, Misiones, Buenos Aires, Mendoza y Chubut. Las mediciones antropométricas de la CB y del pliegue tricipital se realizaron entre 2003 y 2008 siguiendo protocolos estandarizados. Se estimaron las AM, AG, se calcularon los percentilos por edad y sexo, y se compararon mediante el análisis de la varianza. Resultados: Se incluyeron 22 736 escolares (11 397 varones y 11 339 mujeres). Los valores correspondientes al percentilo 50 fueron superiores, en las mujeres, para CB y AG, y, en los varones, para AM. Las curvas de CB presentaron incrementos más marcados a partir de los 7 años en todos los percentilos, para ambos sexos. Un patrón similar se observó para AM, con valores superiores en los varones. Por último, el AG mostró aumento constante en las mujeres y estabilización en los varones a partir de los 11 años. Se observaron diferencias para la edad. Conclusiones: Los valores de percentilos, tabulados y graficados, de la CB y de las AM y AG del brazo pueden constituir una referencia local para estudios epidemiológicos y antropológicos.

Introduction: Mid-upper arm circumference (MUAC) is widely recognized as an adequate indicator of nutritional status. Objective: To estimate the reference percentiles for MUAC, upper arm muscle area (UAMA), and upper arm fat area (UAFA) in the Argentine child and adolescent population using the LMS method (lambda, mu, sigma) Materials and methods: The sample was made up of schoolchildren aged 4.0-13.9 years living in Jujuy, Catamarca, Misiones, Buenos Aires, Mendoza, and Chubut. MUAC and tricipital skinfold anthropometric measurements were obtained between 2003 and 2008 as per standardized protocols. UAMA and UAFA were calculated, and percentiles by age and sex were estimated and compared using an analysis of variance. Results: A total of 22 736 schoolchildren (11 397 boys and 11 339 girls) were included. The 50th percentile was higher for the MUAC and UAFA among girls and for the UAMA among boys. The MUAC curves showed sharper increases as of 7 years old in all percentiles among both boys and girls. A similar pattern was observed for the UAMA, with higher values among boys. Lastly, the UAFA showed a constant increase among girls and a stabilization among boys as of 11 years old. Differences for age were observed. Conclusions: The tabulated and plotted percentiles and the MUAC, UAMA, and UAFA may be used as local references for epidemiological and anthropological studies.

Reference percentiles for mid-upper arm circumference, upper arm muscle and fat areas in the Argentine child and adolescent population (4-14 years old). / Percentilos de referencia de la circunferencia y de las áreas muscular y grasa del brazo para la población infantojuvenil argentina (4-14 años).

INTRODUCTION: Mid-upper arm circumference (MUAC) is widely recognized as an adequate indicator of nutritional status. OBJECTIVE: To estimate the reference percentiles for MUAC, upper arm muscle area (UAMA), and upper arm fat area (UAFA) in the Argentine child and adolescent population using the LMS method (lambda, mu, sigma). MATERIALS AND METHODS: The sample was made up of schoolchildren aged 4.0-13.9 years living in Jujuy, Catamarca, Misiones, Buenos Aires, Mendoza, and Chubut. MUAC and tricipital skinfold anthropometric measurements were obtained between 2003 and 2008 as per standardized protocols. UAMA and UAFA were calculated, and percentiles by age and sex were estimated and compared using an analysis of variance. RESULTS: A total of 22 736 schoolchildren (11 397 boys and 11 339 girls) were included. The 50th percentile was higher for the MUAC and UAFA among girls and for the UAMA among boys. The MUAC curves showed sharper increases as of 7 years old in all percentiles among both boys and girls. A similar pattern was observed for the UAMA, with higher values among boys. Lastly, the UAFA showed a constant increase among girls and a stabilization among boys as of 11 years old. Differences for age were observed. CONCLUSIONS: The tabulated and plotted percentiles and the MUAC, UAMA, and UAFA may be used as local references for epidemiological and anthropological studies.

Introducción: La circunferencia del brazo (CB) se reconoce como buen indicador del estado nutricional. Objetivo: Estimar los percentilos de referencia para la CB y las áreas muscular (AM) y grasa (AG) del brazo en la población infantojuvenil argentina mediante el empleo del método LMS (lambda, mu, sigma, en inglés). Materiales y métodos: La muestra estuvo constituida por escolares de 4,0 a 13,9 años residentes en Jujuy, Catamarca, Misiones, Buenos Aires, Mendoza y Chubut. Las mediciones antropométricas de la CB y del pliegue tricipital se realizaron entre 2003 y 2008 siguiendo protocolos estandarizados. Se estimaron las AM, AG, se calcularon los percentilos por edad y sexo, y se compararon mediante el análisis de la varianza. Resultados: Se incluyeron 22 736 escolares (11 397 varones y 11 339 mujeres). Los valores correspondientes al percentilo 50 fueron superiores, en las mujeres, para CB y AG, y, en los varones, para AM. Las curvas de CB presentaron incrementos más marcados a partir de los 7 años en todos los percentilos, para ambos sexos. Un patrón similar se observó para AM, con valores superiores en los varones. Por último, el AG mostró aumento constante en las mujeres y estabilización en los varones a partir de los 11 años. Se observaron diferencias para la edad. Conclusiones: Los valores de percentilos, tabulados y graficados, de la CB y de las AM y AG del brazo pueden constituir una referencia local para estudios epidemiológicos y antropológicos.

Comparative study of mid-upper arm circumference, arm muscle area and arm fat area percentiles in Argentinean and US children aged 4-14 years / Estudio comparativo de los percentiles de circunferencia, área muscular y área grasa del brazo en niños argentinos y estadounidenses de 4-14 años

Background: mid-upper arm circumference (MUAC), subcutaneous fat and muscle measurements are an alternative method to diagnose overweight and evaluate growth as well as protein and energy reserves. Aim: to compare MUAC, arm muscle area (AMA) and arm fat area (AFA) measurements of Argentinean boys and girls (Sa) with reference curves for US boys and girls (R). Subjects and methods: data from 22,736 school-children aged 4-14 years from six Argentinean provinces were collected. MUAC and triceps skinfold thickness were measured and the derived AMA and AFA measures were calculated. Analyses were performed with GAMLß using the R software. Differences in mean values of Sa and R were compared in percentiles 3, 50 and 97. Results: mean values of MUAC and AMA in boys and girls were higher in R than in Sa at all ages; conversely, AFA values were lower. Conclusions: our results confirm differences in upper arm anthropometry of Argentinean school-children with respect to the US reference. The higher adipose tissue and lower skeletal muscle mass observed in Argentinean children could be partly associated with the different ethnic origin of both populations. However, differences should be interpreted in the context of an obesogenic environment, which has favored a calorie-protein imbalance

Antecedentes: la medición de la circunferencia del brazo (MUAC), así como la estimación de la grasa subcutánea y muscular constituyen un método alternativo para diagnosticar el sobrepeso y evaluar el crecimiento y las reservas proteicas y energéticas. Objetivo: comparar las mediciones de MUAC, área muscular (AMA) y área grasa (AFA) del brazo de niños y niñas argentinos (Sa) con curvas de referencia para niños y niñas de Estados Unidos (R). Sujetos y métodos: se recopilaron datos de 22,736 escolares de 4 a 14 años de edad de seis provincias argentinas. Se obtuvieron medidas de MUAC y pliegue subcutáneo tricipital y se calcularon AMA y AFA. Los análisis se realizaron con GAMLß utilizando el software R. Las diferencias en los valores medios de Sa y R se compararon para los percentiles 3, 50 y 97. Resultados: a todas las edades los valores medios de MUAC y AMA en niños y niñas fueron más altos en R que en Sa; por el contrario, los valores de AFA fueron más bajos. Conclusiones: nuestros resultados confirman la existencia de diferencias en la antropometría mesobraquial de los niños argentinos con respecto a los de la referencia. La mayor cantidad de tejido adiposo y menor de tejido muscular observada en los niños argentinos de ambos sexos puede ser parcialmente asociada con el diferente origen étnico de ambas poblaciones. Sin embargo, las diferencias podrían interpretarse en el contexto de un ambiente obesogénico, el cual habría favorecido el desbalance proteico-calórico

Comparative study of mid-upper arm circumference, arm muscle area and arm fat area percentiles in Argentinean and US children aged 4-14 years.

INTRODUCTION: Background: mid-upper arm circumference (MUAC), subcutaneous fat and muscle measurements are an alternative method to diagnose overweight and evaluate growth as well as protein and energy reserves. Aim: to compare MUAC, arm muscle area (AMA) and arm fat area (AFA) measurements of Argentinean boys and girls (Sa) with reference curves for US boys and girls (R). Subjects and methods: data from 22,736 school-children aged 4-14 years from six Argentinean provinces were collected. MUAC and triceps skinfold thickness were measured and the derived AMA and AFA measures were calculated. Analyses were performed with GAMLSS using the R software. Differences in mean values of Sa and R were compared in percentiles 3, 50 and 97. Results: mean values of MUAC and AMA in boys and girls were higher in R than in Sa at all ages; conversely, AFA values were lower. Conclusions: our results confirm differences in upper arm anthropometry of Argentinean school-children with respect to the US reference. The higher adipose tissue and lower skeletal muscle mass observed in Argentinean children could be partly associated with the different ethnic origin of both populations. However, differences should be interpreted in the context of an obesogenic environment, which has favored a calorie-protein imbalance.

INTRODUCCIÓN: Antecedentes: la medición de la circunferencia del brazo (MUAC), así como la estimación de la grasa subcutánea y muscular constituyen un método alternativo para diagnosticar el sobrepeso y evaluar el crecimiento y las reservas proteicas y energéticas. Objetivo: comparar las mediciones de MUAC, área muscular (AMA) y área grasa (AFA) del brazo de niños y niñas argentinos (Sa) con curvas de referencia para niños y niñas de Estados Unidos (R). Sujetos y métodos: se recopilaron datos de 22,736 escolares de 4 a 14 años de edad de seis provincias argentinas. Se obtuvieron medidas de MUAC y pliegue subcutáneo tricipital y se calcularon AMA y AFA. Los análisis se realizaron con GAMLSS utilizando el software R. Las diferencias en los valores medios de Sa y R se compararon para los percentiles 3, 50 y 97. Resultados: a todas las edades los valores medios de MUAC y AMA en niños y niñas fueron más altos en R que en Sa; por el contrario, los valores de AFA fueron más bajos. Conclusiones: nuestros resultados confirman la existencia de diferencias en la antropometría mesobraquial de los niños argentinos con respecto a los de la referencia. La mayor cantidad de tejido adiposo y menor de tejido muscular observada en los niños argentinos de ambos sexos puede ser parcialmente asociada con el diferente origen étnico de ambas poblaciones. Sin embargo, las diferencias podrían interpretarse en el contexto de un ambiente obesogénico, el cual habría favorecido el desbalance proteico-calórico.

Doble carga de malnutrición y nivel de bienestar socio-ambiental de escolares de la Patagonia argentina(Puerto Madryn, Chubut) / Double burden of malnutrition and socio-environmental well-being in schoolchildren from Argentinian Patagonia (Puerto Madryn, Chubut)

INTRODUCCIÓN: La doble carga de la malnutrición constituye un desafío para la salud pública y una problemática creciente en Latinoamérica y el Caribe. El análisis poblacional de Puerto Madryn resulta interesante visto que esta ciudad registró desde 1970 el mayor crecimiento demográfico de Argentina. No obstante, la reducción en el nivel de industrialización podría haber repercutido en el bienestar de los habitantes. OBJETIVO: Evaluar la asociación entre el estado nutricional y el nivel de bienestar socio-ambiental de escolares, de 6 a 14 años de edad, residentes en Puerto Madryn (Chubut, Argentina). MÉTODOS: Se relevaron peso y talla en 2799 escolares y se empleó la referencia de la Organización Mundial de la Salud para determinar: desnutrición, sobrepeso y obesidad. Las prevalencias entre grupos y sexos fueron comparadas por Chi2. El nivel de bienestar de las familias se indagó mediante encuestas que fueron procesadas por Análisis de Compo nentes Principales categórico (ACP-cat). RESULTADOS: El ACP-cat diferenció dos grupos: uno con mayor (MaB) y otro menor (MeB) bienestar socio-ambiental. El MaB se caracterizó por presentar viviendas con paredes de ladrillos y pisos revestidos, acceso a servicios públicos, cobertura de salud por obra social o prepaga y padres con trabajo formal. El MeB en cambio, presentó viviendas con paredes de chapa y/o madera, pisos de cemento o tierra, hacinamiento, asistencia a hospitales públicos y padres con trabajo informal. Se observó presencia de desnutrición (2,6%) y exceso de peso (46,9%). La prevalencia de sobrepeso fue mayor que la de obesidad (25.7% vs.21.3%). La desnutrición crónica y el sobrepeso fueron 2,1% y 3,6% superiores en los escolares con MeB. CONCLUSIÓN: La población escolar de Puerto Madryn presenta doble carga de malnutrición, característica de un estadio avanzado de transición nutricional. Las mayores prevalencias de desnutrición crónica y sobrepeso se asocian a menores condiciones socio-ambientales. La obesidad en cambio, se presenta independientemente del nivel de bienestar socio-ambiental

INTRODUCTION: The double burden of malnutrition constitutes a challenge for public health and an increasing problem in Latin America and the Caribbean. The population analysis of Puerto Madryn is interesting given that this city recorded since 1970 the highest demographic growth in Argentina. However, the reduction in the level of industrialization could have had an impact on the well-being of the inhabitants. OBJECTIVE: To determine the association between nutritional status and socio-environmental well-being in 6-14 year-old schoolchildren from Puerto Madryn, Chubut, Argentina. METHODS: Weight and height were assessed in 2799 schoolchildren and the World Health Organization reference was used to determine: malnutrition, overweight and obesity. Prevalence between groups and sexes were compared with Chi-square. Family well-being was surveyed with questionnaires and analyzed with categorical Principal Component Analysis (cat-PCA). RESULTS: The cat-PCA differentiated two groups of well-being: major (MA) and minor (MI). The MA group was characterized by the presence of houses with brick walls and coated floors, accessibility to public services, health insurance (medical insurance at the expense of the employer or paid by the person) and parents with formal employment. In the MI group, houses had zinc-metal or wood walls, concrete or earthen floors, households were overcrowded, health care was provided by the assistance public hospitals and parents had informal employment. The prevalence of malnutrition was 2.6% and that of excess weight was 46.9%. The prevalence of overweight was higher than that of obesity (25.7% vs.21.3%). Stunting and overweight were 2.1% and 3.6% higher in schoolchildren from the MI group. CONCLUSION: The schoolchildren population from Puerto Madryn presents double burden of malnutrition, characteristic of an advanced stage of nutritional transition. The higher prevalence of stunting and overweight are associated with lower socio-environmental conditions. Nevertheless, obesity occurs independently of these conditions socio-environmental well-being

[Malnutrition and structural poverty. Comparison of two schoolchildren cohorts from Puerto Madryn, Argentina]. / Malnutrición y pobreza estructural. Comparación de dos cohortes de escolares de Puerto Madryn, Argentina.

OBJECTIVE: To assess nutritional condition in two cohorts (C) of children from households with different Unsatisfied Basic Needs (UBN) attending neighborhood schools in Puerto Madryn, Argentina. METHODS: A cross-sectional study on six to 11 year-old children attending seven neighborhood schools surveyed in the periods 2001-2006 (C1, n=2 040) and 2014-2016 (C2, n=1 696) was performed. Weight, height and body mass index were measured using the World Health Organization cut-off values for nutritional condition. Neighborhood structural poverty was determined with percent UBN from the 2001 and 2010 census. Chi2 was used to compare the prevalence of nutritional condition between C and UBN categories. RESULTS: In the seven neighborhoods analyzed, percent UBN was 0%-10% (n=3), 10%-25% (n=2) and 25%-50% (n=1), without changes in the period 2001-2010. In the remaining neighborhood, UBN increased from 25%-50% to >50%. The nutritional evaluation of children showed significant differences in the prevalence of obesity in most schools, while low height-for-age and overweight prevalence was significant only in one school. Comparison of C1 and C2 only showed significant differences in the prevalence of obesity. CONCLUSIONS: Structural poverty rates in Puerto Madryn neighborhoods were mostly unchanged; however, the nutritional condition of children was different: while the prevalence of chronic malnutrition did not change or decreased, the prevalence of obesity increased in all neighborhoods. Our findings could help to determine changes in the context of resident population and identify vulnerable groups.

OBJETIVO: Estimar el estado nutricional de dos cohortes (C) de niños concurrentes a escuelas de barrios con diferentes Necesidades Básicas Insatisfechas (NBI) de Puerto Madryn, Argentina. MÉTODOS: Investigación transversal. Se midieron peso y talla de niños de seis a 11 años asistentes a escuelas ubicadas en siete barrios. La C1 (n=2 040) fue relevada entre 2001-2006 y C2 (n=1 696) entre 2014-2016. Se calculó el Índice de Masa Corporal y se emplearon los puntos de corte de la OMS para determinar el estado nutricional. Para estimar la pobreza estructural se extrajeron, para 2001 y 2010, los porcentajes de NBI censales de cada barrio. Las prevalencias de estado nutricional entre cohortes y categorías de NBI se compararon mediante Chi2. RESULTADOS: En los siete barrios analizados, las NBI fueron: 0%-10% (n=3), 10%-25% (n=2) y 25%-50% (n=1), sin variación entre 2001-2010. En otro barrio, las NBI aumentaron de 25%-50% a >50%. Al evaluar el estado nutricional de los niños de cada escuela hubo diferencias para obesidad en la mayoría de ellas y para baja talla/edad y sobrepeso solo en una. La comparación C1-C2 indicó diferencias para obesidad. CONCLUSIONES: Los barrios de Puerto Madryn conservan, en gran parte, sus niveles de pobreza estructural. No ocurre lo mismo con el estado nutricional de los niños: mientras las prevalencias de desnutrición crónica se mantienen o descienden, las de obesidad aumentan en todos los barrios. El análisis efectuado permite evaluar transformaciones del contexto de residencia de la población e identificar grupos vulnerables.

Malnutrición y pobreza estructural. Comparación de dos cohortes de escolares de Puerto Madryn, Argentina / Malnutrition and structural poverty. Comparison of two schoolchildren cohorts from Puerto Madryn, Argentina

RESUMEN Objetivo Estimar el estado nutricional de dos cohortes (C) de niños concurrentes a escuelas de barrios con diferentes Necesidades Básicas Insatisfechas (NBI) de Puerto Madryn, Argentina. Métodos Investigación transversal. Se midieron peso y talla de niños de seis a 11 años asistentes a escuelas ubicadas en siete barrios. La C1 (n=2 040) fue relevada entre 2001-2006 y C2 (n=1 696) entre 2014-2016. Se calculó el Índice de Masa Corporal y se emplearon los puntos de corte de la OMS para determinar el estado nutricional. Para estimar la pobreza estructural se extrajeron, para 2001 y 2010, los porcentajes de NBI censales de cada barrio. Las prevalencias de estado nutricional entre cohortes y categorías de NBI se compararon mediante Chi2. Resultados En los siete barrios analizados, las NBI fueron: 0%-10% (n=3), 10%-25% (n=2) y 25%-50% (n=1), sin variación entre 2001-2010. En otro barrio, las NBI aumentaron de 25%-50% a >50%. Al evaluar el estado nutricional de los niños de cada escuela hubo diferencias para obesidad en la mayoría de ellas y para baja talla/edad y sobrepeso solo en una. La comparación C1-C2 indicó diferencias para obesidad. Conclusiones Los barrios de Puerto Madryn conservan, en gran parte, sus niveles de pobreza estructural. No ocurre lo mismo con el estado nutricional de los niños: mientras las prevalencias de desnutrición crónica se mantienen o descienden, las de obesidad aumentan en todos los barrios. El análisis efectuado permite evaluar transformaciones del contexto de residencia de la población e identificar grupos vulnerables.(AU)

ABSTRACT Objective To assess nutritional condition in two cohorts (C) of children from households with different Unsatisfied Basic Needs (UBN) attending neighborhood schools in Puerto Madryn, Argentina. Methods A cross-sectional study on six to 11 year-old children attending seven neighborhood schools surveyed in the periods 2001-2006 (C1, n=2 040) and 2014-2016 (C2, n=1 696) was performed. Weight, height and body mass index were measured using the World Health Organization cut-off values for nutritional condition. Neighborhood structural poverty was determined with percent UBN from the 2001 and 2010 census. Chi2 was used to compare the prevalence of nutritional condition between C and UBN categories. Results In the seven neighborhoods analyzed, percent UBN was 0%-10% (n=3), 10%-25% (n=2) and 25%-50% (n=1), without changes in the period 2001-2010. In the remaining neighborhood, UBN increased from 25%-50% to >50%. The nutritional evaluation of children showed significant differences in the prevalence of obesity in most schools, while low height-for-age and overweight prevalence was significant only in one school. Comparison of C1 and C2 only showed significant differences in the prevalence of obesity. Conclusions Structural poverty rates in Puerto Madryn neighborhoods were mostly unchanged; however, the nutritional condition of children was different: while the prevalence of chronic malnutrition did not change or decreased, the prevalence of obesity increased in all neighborhoods. Our findings could help to determine changes in the context of resident population and identify vulnerable groups.(AU)

[Cross-sectional study of intestinal parasitosis in child populations in Argentina]. / Estudio transversal de las parasitosis intestinales en poblaciones infantiles de Argentina.

OBJECTIVE: Determine the distribution of intestinal parasitosis in children in nine provinces representative of Argentina's mosaic of contrasting environments. METHODS: Descriptive, observational, cross-sectional study of preschool children (5 years old or under) and school-age children (6-14 years) in the provinces of Buenos Aires (sample taken between 2005 and 2013), Chubut (2010-2013), Corrientes (2012), Entre Ríos (2010-2012), Formosa (2014), La Pampa (2006), Mendoza (2008-2011), Misiones (2005-2008 and 2013), and Salta (2012-2013). Serial samples, fecal samples, and anal swabs were processed using concentration techniques. The results were analyzed by sex, age interval, and province. Frequency of parasitosis (monoparasitosis and multiple parasitoses), wealth of species, and Sørensen similarity coefficient were calculated. RESULTS: Misiones presented the highest frequency of parasitized children and Chubut the lowest (82.0% vs 38.4%; p < 0.01). The number of species was greatest in Misiones and Buenos Aires and lowest in Chubut and La Pampa. Men were parasitized more than women only in Buenos Aires. The highest frequencies were found in preschool children in Buenos Aires and schoolchildren in Mendoza and Misiones (p < 0.05). Monoparasitosis was most frequent in Chubut (67.9%) and multiple parasitosis in Formosa (69.2%). The most frequent species in the majority of provinces were Blastocystis sp. and Enterobius vermicularis. Misiones presented the highest frequency of soil-transmitted helminthes (23.3%) and Mendoza the lowest (0.6%); none were found in Chubut, La Pampa, or Salta. Buenos Aires, Formosa, and Misiones presented a similar species composition, as did Chubut and La Pampa. CONCLUSIONS: The frequency of parasitosis in Argentina corresponds to the country's complex mosaic of climatic and socioeconomic variability and shows a declining trend from north to south and from east to west.

Estudio transversal de las parasitosis intestinales en poblaciones infantiles de Argentina / Cross-sectional study of intestinal parasitosis in child populations in Argentina

Objetivo. Determinar la distribución de las enteroparasitosis en niños de nueve provincias representativas del mosaico de ambientes contrastantes de Argentina. Métodos. Estudio descriptivo, observacional y transversal en niños preescolares (de 5 años o menos) y escolares (de 6 a 14 años) de las provincias de Buenos Aires (muestra tomada entre 2005 y 2013), Chubut (2010-2013), Corrientes (2012), Entre Ríos (2010-2012), Formosa (2014), La Pampa (2006), Mendoza (2008-2011), Misiones (2005-2008 y 2013) y Salta (2012-2013). Se procesaron muestras seriadas, fecales y de escobillado anal, mediante técnicas de concentración. Los resultados se analizaron por sexo, intervalo de edad y provincia. Se calcularon la frecuencia de parasitosis (monoparasitosis y parasitosis múltiple), la riqueza de especies y el coeficiente de similitud de Sørensen. Resultados. Misiones presentó la mayor frecuencia de niños parasitados y Chubut la menor (82,0% vs. 38,4%; p ˂ 0,01). El número de especies fue mayor en Misiones y Buenos Aires y menor en Chubut y La Pampa. Los varones estuvieron más parasitados que las mujeres solo en Buenos Aires. Las mayores frecuencias se encontraron en los preescolares de Buenos Aires y los escolares de Mendoza y Misiones (p < 0,05). La monoparasitosis fue más frecuente en Chubut (67,9%) y las parasitosis múltiples en Formosa (69,2%). Las especies más frecuentes en la mayoría de las provincias fueron Blastocystis sp. y Enterobius vermicularis. De los geohelmintos, Misiones presentó la mayor frecuencia (23,3%) y Mendoza la menor (0,6%); no se hallaron en Chubut, La Pampa y Salta. Buenos Aires, Formosa y Misiones presentaron una composición de especies similar, al igual que Chubut y La Pampa. Conclusiones. Las frecuencias de parasitosis en Argentina responden al complejo mosaico de variabilidad climática y socioeconómica del país y revelan una tendencia descendente de norte a sur y de este a oeste.

Objective. Determine the distribution of intestinal parasitosis in children in nine provinces representative of Argentina’s mosaic of contrasting environments. Methods. Descriptive, observational, cross-sectional study of preschool children (5 years old or under) and school-age children (6-14 years) in the provinces of Buenos Aires (sample taken between 2005 and 2013), Chubut (2010-2013), Corrientes (2012), Entre Ríos (2010-2012), Formosa (2014), La Pampa (2006), Mendoza (2008-2011), Misiones (2005-2008 and 2013), and Salta (2012-2013). Serial samples, fecal samples, and anal swabs were processed using concentration techniques. The results were analyzed by sex, age interval, and province. Frequency of parasitosis (monoparasitosis and multiple parasitoses), wealth of species, and Sørensen similarity coefficient were calculated. Results. Misiones presented the highest frequency of parasitized children and Chubut the lowest (82.0% vs 38.4%; p < 0.01). The number of species was greatest in Misiones and Buenos Aires and lowest in Chubut and La Pampa. Men were parasitized more than women only in Buenos Aires. The highest frequencies were found in preschool children in Buenos Aires and schoolchildren in Mendoza and Misiones (p < 0.05). Monoparasitosis was most frequent in Chubut (67.9%) and multiple parasitosis in Formosa (69.2%). The most frequent species in the majority of provinces were Blastocystis sp. and Enterobius vermicularis. Misiones presented the highest frequency of soil-transmitted helminthes (23.3%) and Mendoza the lowest (0.6%); none were found in Chubut, La Pampa, or Salta. Buenos Aires, Formosa, and Misiones presented a similar species composition, as did Chubut and La Pampa. Conclusions. The frequency of parasitosis in Argentina corresponds to the country’s complex mosaic of climatic and socioeconomic variability and shows a declining trend from north to south and from east to west.

Suprascapular ligament ossification and nerve entrapment in a modern skeleton from the central coast of Patagonia, Southern South America

Modification of the suprascapular notch into a foramen as a consequence of the ossification of the suprascapular transverse ligament is a well-known anatomical change. However, it was rarely considered by research in skeletal and cadaveric remains as a possible cause of Suprascapular Nerve Entrapment, a neuropathy that usually produces pain and weakness of the affected shoulder. This paper has the aim to present and to discuss a case of ossification of the suprascapular transverse ligament in a modern-era, possible archaeological male skeleton of 30-45 years old from the central coast of Patagonia, and a possible development of suprascapular nerve entrapment. Complete bilateral ossification of the superior transverse scapular ligament was identified. As no other morphological, traumatic or neoplastic lesions were found in the scapulae, physical activity is suggested as the cause of the ligament ossification in the skeleton, although epigenetic origin cannot be completely rejected

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Composición corporal en relación al sobrepeso y a la obesidad. Un estudio en niños residentes en diferentes áreas geográficas de Argentina / Relationship between body composition and overweight/obesity. A study in children living in different geographic areas from Argentina

Introducción: En las últimas décadas se ha observado un rápido incremento del exceso de peso. Las dificultades para acceder a una alimentación adecuada, predisponen a los niños a presentar sobrepeso u obesidad y muchos de ellos resultan además anémicos o con déficit de tejido muscular. Objetivo: Analizar la composición corporal de niños con sobrepeso u obesidad, residentes en dos ciudades argentinas con diferente localización geográfica: General Alvear (Mendoza) y Puerto Madryn (Chubut). Métodos: Se realizó un estudio transversal en 5828 escolares (3048 varones y 2780 mujeres) desde los 5,0 a los 14,9 años de edad residentes en las ciudades de General Alvear (GA) y Puerto Madryn (PM). Se relevaron: peso, talla, perí- metro braquial y pliegues tricipital y subescapular y se calcularon las áreas muscular y adiposa del brazo y el Índice Subescapular/Tricipital (IST). Las prevalencias de sobrepeso (S) y obesidad (O) se estimaron utilizando NHANES III (S>P85 y ≤P95 y O>P95). El análisis de la composición corporal mesobraquial se realizó estimando déficit y exceso de tejidos adiposo (DTA, ETA) y muscular (DTM, ETM). Resultados: Las prevalencias de S y O fueron mayores en PM respecto a GA (S=13,1% vs 7,0%) y (O= 9,0% vs 4,8%). En GA se registraron los mayores porcentajes de niños con DTM y ETA mientras que en PM aquellos con ETM. En niños y niñas de ambas ciudades se encontraron valores de IST>1. No obstante, estos se manifestaron a edades más tempranas principalmente en niñas obesas. Discusión y Conclusiones: El ambiente urbano de PM y su estilo de vida, conducen a que la población infanto-juvenil presente mayor exceso de peso, como consecuencia del aumento en los tejidos adiposo y muscular. La mayor centralización adiposa en niñas puede conducir al desarrollo de enfermedades no trasmisibles. Por otra parte, aun cuando el exceso de peso es menor en GA, la condición de estos niños es también preocupante, puesto que el exceso de tejido adiposo se acompaña de déficit de tejido muscular, posiblemente como consecuencia de ingestas altamente calóricas pero proteicamente deficientes (AU)

Introduction: In the recent decades a rapid increase of excess weight has been observed. Difficulties in having access to adequate food predispose children to being overweight or obese and many of them are also anemic or have a deficit in the muscle tissue. Objective: To analyze the body composition of overweight or obese children living in two Argentinean cities with different geographical locations: General Alvear (Mendoza) and Puerto Madryn (Chubut). Methods: A cross-sectional study was carried out on 5828 schoolchildren (3048 males and 2780 females) aged from 5,0 to 14,9 living in the cities of General Alvear (GA) and Puerto Madryn (PM). Weight, height, upper arm circumference and tricipital and subscapular skinfolds were measured. Also, muscle and adipose areas of the arm and Subscapular/Tricipital Index (STI) were calculated. The prevalence of overweight (O) and obesity (Ob) were estimated using NHANES III (O> P85 and ≤P95 and Ob> P95). The analysis of body composition was performed in the arm estimating deficit and excess of adipose (DAT, EAT) and muscular tissues (DMT, EMT). Results: The O and Ob prevalence was higher in PM than in GA (O= 13.1% vs 7.0%) and (Ob= 9.0% vs 4.8%). The highest percentages of children with DMT and EAT were recorded in GA, whereas those with EMT were recorded in PM. The STI values >1 were found in boys and girls from both cities. Nevertheless, they appear at early ages mainly in obese girls. Discussion and Conclusions: The urban environment of PM and its lifestyle result in a child-juvenile population whit greater excess of weight, as a consequence of the increase in adipose and muscular tissues. The centralization of adipose tissue in girls could lead to the development of non-communicable diseases. On the other hand, even when excess of weight is lower in GA the condition of these children is as worrying, since excess of adipose tissue is accompanied by muscle tissue deficit, possibly as a consequence of highly caloric but poorly protein intakes (AU)

Estudio transversal de las parasitosis intestinales en poblaciones infantiles de Argentina / Cross-sectional study of intestinal parasitosis in child populations in Argentina

RESUMEN Objetivo Determinar la distribución de las enteroparasitosis en niños de nueve provincias representativas del mosaico de ambientes contrastantes de Argentina. Métodos Estudio descriptivo, observacional y transversal en niños preescolares (de 5 años o menos) y escolares (de 6 a 14 años) de las provincias de Buenos Aires (muestra tomada entre 2005 y 2013), Chubut (2010-2013), Corrientes (2012), Entre Ríos (2010-2012), Formosa (2014), La Pampa (2006), Mendoza (2008-2011), Misiones (2005-2008 y 2013) y Salta (2012-2013). Se procesaron muestras seriadas, fecales y de escobillado anal, mediante técnicas de concentración. Los resultados se analizaron por sexo, intervalo de edad y provincia. Se calcularon la frecuencia de parasitosis (monoparasitosis y parasitosis múltiple), la riqueza de especies y el coeficiente de similitud de Sørensen. Resultados Misiones presentó la mayor frecuencia de niños parasitados y Chubut la menor (82,0% vs. 38,4%; p ˂ 0,01). El número de especies fue mayor en Misiones y Buenos Aires y menor en Chubut y La Pampa. Los varones estuvieron más parasitados que las mujeres solo en Buenos Aires. Las mayores frecuencias se encontraron en los preescolares de Buenos Aires y los escolares de Mendoza y Misiones (p < 0,05). La monoparasitosis fue más frecuente en Chubut (67,9%) y las parasitosis múltiples en Formosa (69,2%). Las especies más frecuentes en la mayoría de las provincias fueron Blastocystis sp. y Enterobius vermicularis. De los geohelmintos, Misiones presentó la mayor frecuencia (23,3%) y Mendoza la menor (0,6%); no se hallaron en Chubut, La Pampa y Salta. Buenos Aires, Formosa y Misiones presentaron una composición de especies similar, al igual que Chubut y La Pampa. Conclusiones Las frecuencias de parasitosis en Argentina responden al complejo mosaico de variabilidad climática y socioeconómica del país y revelan una tendencia descendente de norte a sur y de este a oeste.

ABSTRACT Objective Determine the distribution of intestinal parasitosis in children in nine provinces representative of Argentina’s mosaic of contrasting environments. Methods Descriptive, observational, cross-sectional study of preschool children (5 years old or under) and school-age children (6-14 years) in the provinces of Buenos Aires (sample taken between 2005 and 2013), Chubut (2010-2013), Corrientes (2012), Entre Ríos (2010-2012), Formosa (2014), La Pampa (2006), Mendoza (2008-2011), Misiones (2005-2008 and 2013), and Salta (2012-2013). Serial samples, fecal samples, and anal swabs were processed using concentration techniques. The results were analyzed by sex, age interval, and province. Frequency of parasitosis (monoparasitosis and multiple parasitoses), wealth of species, and Sørensen similarity coefficient were calculated. Results Misiones presented the highest frequency of parasitized children and Chubut the lowest (82.0% vs 38.4%; p < 0.01). The number of species was greatest in Misiones and Buenos Aires and lowest in Chubut and La Pampa. Men were parasitized more than women only in Buenos Aires. The highest frequencies were found in preschool children in Buenos Aires and schoolchildren in Mendoza and Misiones (p < 0.05). Monoparasitosis was most frequent in Chubut (67.9%) and multiple parasitosis in Formosa (69.2%). The most frequent species in the majority of provinces were Blastocystis sp. and Enterobius vermicularis. Misiones presented the highest frequency of soil-transmitted helminthes (23.3%) and Mendoza the lowest (0.6%); none were found in Chubut, La Pampa, or Salta. Buenos Aires, Formosa, and Misiones presented a similar species composition, as did Chubut and La Pampa. Conclusions The frequency of parasitosis in Argentina corresponds to the country’s complex mosaic of climatic and socioeconomic variability and shows a declining trend from north to south and from east to west.

Weight and height percentiles calculated by the LMS method in Argentinean schoolchildren. A comparative references study.

BACKGROUND: The Argentinean population is characterized by ethnic, cultural and socio-economic diversity. AIM: To calculate the percentiles of weight-for-age (W/A) and height-for-age (H/A) of schoolchildren from Argentina employing the LMS method; and to compare the obtained percentiles with those of the international and national references. SUBJECTS AND METHODS: Anthropometric data of 18 698 students (8672 girls and 10 026 boys) of 3-13 years old were collected (2003-2008) from Buenos Aires, Catamarca, Chubut, Jujuy, La Pampa and Mendoza. Percentiles of W/A and H/A were obtained with the LMS method. Statistical and graphical comparisons were established with the WHO (international reference) and with that published by the Argentinean Paediatric Society (national reference). RESULTS: Differences in W/A and H/A, regarding the references, were negative and greater at the highest percentiles and in most of the age groups. On average, the differences were greater for boys than girls and for national than international references. CONCLUSION: The distribution of weight and height of schoolchildren, coming from most regions of the country, differs from those of national and international references. It should be advisable to establish a new national reference based on internationally recognized methodological criteria that adequately reflect the biological and cultural diversity of the Argentinean populations.

Origin of Fueguian-Patagonians: an approach to population history and structure using R matrix and matrix permutation methods.

A complicated history of isolation between Fueguian and Patagonian groups (originated by the appearance of the Straits of Magellan) as much as differences in population structure and life strategies constitute important factors in the clustering pattern of those groups. The aim of this work was to test several hypotheses about population structure and history of Fueguian-Patagonians to propose a model that incorporates predictions for future studies. R matrix methods and matrix permutation analyses were performed upon a data matrix of craniofacial measurements of 441 skulls divided into nine samples pertaining to six Patagonian and three Fueguian populations. Association of biological distances with three matrices representing several settlement patterns was tested using matrix permutation tests. Results of R matrix study show that the minimum genetic distance obtained confirms separation between Fueguians and Patagonians. Moreover, an analysis of residual variances from the expected regression line confirms admixture between Andean and Pampean populations and Araucanian groups, consistent with ethnohistorical observations. A model representing a long history of isolation between Fueguian and Patagonians, rather than a model emphasizing differences in life-strategies, presented the best correlation with the biological distance matrix. Because similar results were already obtained in archaeological, molecular, and morphological studies, a model for the settlement of Tierra del Fuego is proposed. It is summarized by four main hypotheses that can be tested independently by different disciplines in the future.