Blood Lead Levels and Their Association with Iron Deficiency and Anemia in Children.

Lead is a ubiquitous and neurotoxic heavy metal particularly harmful to children, who are more susceptible than adults to its toxic effects. The prevalence of lead poisoning and iron deficiency (ID) is high in socioeconomically vulnerable child populations, negatively affecting neurocognitive development in children. Although numerous studies have shown the association between blood lead levels (BLL) and ID, the issue remains controversial. Here, we aimed to identify the association between BLL and iron nutritional status in children. We conducted an analytical cross-sectional study of healthy children aged 1-6 y attending periodic health checks in primary healthcare units from La Plata and its surroundings, Buenos Aires, Argentina, between 2012 and 2017. We performed anthropometric evaluations and determined BLL, hemoglobin (Hb) and serum ferritin levels. Blood lead levels ≥ 5 µg/dL were defined as elevated BLL; ferritin levels < 12 ng/ml were considered ID; Hb levels < 11 g/dL (< 11.5 g/dL for children ≥ 5 y) were defined as anemia. Data were analysed using Mann Whitney test, Student´s t-test, chi-square test and logistic regression. The R package (v. 4.2.2.) was used for the statistical analysis of data. The sample included 392 children (mean age, 2.4 ± 1.4 y; 44.6% females). The prevalence of elevated BLL, ID and anemia was 8.7%, 26.3% and 31.8%, respectively. We found a significant association between elevated BLL and ID (odds ratio [OR], 95% confidence interval [CI]: 3.16 (1.50, 6.63)). The prevalence of elevated BLL was 16.2% and 5.8% in children with and without ID, respectively (p = 0.003). We also found association between elevated BLL and anemia (OR 95% CI: 3.03 (1.49, 6.29)). In conclusion, blood lead levels ≥ 5 µg/dL were significantly associated with ID and anemia in children aged 1-6 years.

A function of spalt major as a sequence-specific DNA binding transcription factor mediates repression of knirps in the Drosophila wing imaginal disc.

The Spalt transcriptional regulators participate in a variety of cell fate decisions during multicellular development. Vertebrate Spalt proteins have been mostly associated to the organization of heterochromatic regions, but they also contribute regulatory functions through binding to A/T rich motives present in their target genes. The developmental processes in which the Drosophila spalt genes participate are well known through genetic analysis, but the mechanism by which the Spalt proteins regulate transcription are still unknown. Furthermore, despite the prominent changes in gene expression associated to mutations in the spalt genes, the specific DNA sequences they bind are unknow. Here, we analyze a DNA fragment present in the regulatory region of the knirps gene. Spalt proteins are candidate repressors of knirps expression during the formation of the venation pattern in the wing disc, and we identified a minimal conserved 30bp sequence that binds to Spalt major both in vivo and in vitro. This sequence mediates transcriptional repression in the central region of the wing blade, constituting the first confirmed case of a direct regulatory interaction between Spalt major and its target DNA in Drosophila. Interestingly, we also find similar sequences in a set of eight novel candidate Spalt target genes, pointing to a common mechanism of transcriptional repression mediated by Spalt proteins.

Leptin receptor expression in blood mononuclear cells of lactating women is associated with infant body weight: Potential role as a molecular biomarker.

BACKGROUND: Molecular biomarkers of maternal leptin resistance associated with infant weight are needed. OBJECTIVES: To evaluate gene expression of leptin receptor (LEPR), suppressor of cytokine signalling 3 (SOCS3) and insulin receptor in peripheral blood mononuclear cells (PBMCs) of lactating women and their relationship with infant body weight and adiposity. METHODS: At day 10 postpartum, maternal gene expression in PBMCs as well as leptin and insulin concentrations in plasma and milk were assessed (n = 68). Infant weight and BMI z-scores, skinfolds and arm circumference were obtained at 10 days and/or at 3 months old. RESULTS: In mothers with pre-pregnancy overweight or obesity (OW/OB), LEPR expression was reduced (p = 0.013) whereas plasma and milk leptin and milk insulin concentrations were elevated. LEPR expression was positively related with infant weight z-score (Beta (95% CI): 0.40 (0.17, 0.63), p = 0.001) but not with leptin concentrations. SOCS3 expression was positively related with infant weight z-score (Beta (95% CI): 0.28 (0.04, 0.51), p = 0.024) and arm circumference (Beta (95% CI): 0.57 (0.32, 0.82), p < 0.001). Relationships remained significant after adjusting for maternal and infant confounders. CONCLUSIONS: LEPR and SOCS3 gene expression in PBMCs are novel maternal molecular biomarkers that reflect leptin resistance and are associated with infant body weight and adiposity.

Efectividad de la administración de hierro en forma semanal y diaria para la prevención de anemia por deficiencia de hierro en lactantes / Effectiveness of weekly and daily iron administration for the prevention of iron deficiency anemia in infants

Introducción. La deficiencia de hierro (DH) es la carencia nutricional más prevalente y la principal causa de anemia en lactantes. Existe consenso en la suplementación diaria con hierro como estrategia de prevención; también se demostró que la suplementación semanal es eficaz, pero la evidencia en lactantes es escasa. El objetivo fue comparar la efectividad de la administración diaria de hierro frente a la semanal para la prevención de la anemia por DH del lactante. Población y métodos. Ensayo clínico controlado y aleatorizado. Lactantes atendidos en un centro de salud público, sin anemia a los 3 meses de edad, aleatorizados en tres grupos: suplementación diaria (1 mg/kg/día), semanal (4 mg/kg/semana) o sin suplementación (grupo control con lactancia materna exclusiva [LME]). Se evaluó anemia y DH a los 3 y 6 meses. Se registró grado de adherencia y efectos adversos. Los datos se analizaron con el software R versión 4.0.3. Resultados. Participaron 227 lactantes. A los 6 meses el grupo de lactantes con LME sin suplementación (control) presentó prevalencias de DH y anemia por DH (ADH) mayores que los grupos intervenidos (diario y semanal). DH: 40,5 % vs. 13,5 % y 16,7 % (p = 0,002); ADH: 33,3 % vs. 7,8 % y 10 % (p < 0,001). No hubo diferencias entre los grupos diario y semanal. Tampoco hubo diferencias en el porcentaje de alta adherencia a la suplementación (50,6 % diaria vs. 57,1 % semanal), ni en los efectos adversos. Conclusiones. No se hallaron diferencias significativas en la efectividad entre la administración diaria y semanal para la prevención de ADH del lactante.

Introduction. Iron deficiency (ID) is the most prevalent nutritional deficiency and the main cause of anemia in infants. There is consensus on daily iron supplementation as a preventive strategy; and weekly iron supplementation has also been shown to be effective, but evidence in infants is scarce. The objective of this study was to compare the effectiveness of daily versus weekly iron administration for the prevention of ID anemia (IDA) in infants. Population and methods. Randomized, controlled clinical trial. Infants seen at a public health center, without anemia at 3 months of age, were randomized into 3 groups: daily supplementation (1 mg/kg/ day), weekly supplementation (4 mg/kg/week), or no supplementation (control group with exclusive breastfeeding [EB]). Anemia and ID were assessed at 3 and 6 months old. Adherence and adverse events were recorded. Data were analyzed using the R software, version 4.0.3. Results. A total of 227 infants participated. At 6 months, the group of infants with EB without supplementation(control) had a higher prevalence of ID and IDA than the intervention groups (daily and weekly). ID: 40.5% versus 13.5% and 16.7% (p = 0.002); IDA: 33.3% versus 7.8% and 10% (p < 0.001). There were no differences between the daily and weekly supplementation groups. There were also no differences in the percentage of high adherence to supplementation (50.6% daily versus 57.1% weekly) or adverse events. Conclusions. No significant differences in effectiveness were observed between daily and weekly administration for the prevention of infant IDA.

RNAi screen in the Drosophila wing of genes encoding proteins related to cytoskeleton organization and cell division.

Cell division and cytoskeleton organization are fundamental processes participating in the development of Drosophila imaginal discs. In this manuscript we describe the phenotypes in the adult fly wing generated by knockdowns of 85% of Drosophila genes encoding proteins likely related to the regulation of cell division and cytoskeleton organization. We also compile a molecular classification of these proteins into classes that describe their expected or known main biochemical characteristics, as well as mRNA expression in the wing disc and likely protein subcellular localization for a subset of these genes. Finally, we analyze in more detail one protein family of cytoskeleton genes (Arp2/3 complex), and define the consequences of interfering with cell division for wing growth and patterning.

Effectiveness of weekly and daily iron administration for the prevention of iron deficiency anemia in infants. / Efectividad de la administración de hierro en forma semanal y diaria para la prevención de anemia por deficiencia de hierro en lactantes.

Introduction. Iron deficiency (ID) is the most prevalent nutritional deficiency and the main cause of anemia in infants. There is consensus on daily iron supplementation as a preventive strategy; and weekly iron supplementation has also been shown to be effective, but evidence in infants is scarce. The objective of this study was to compare the effectiveness of daily versus weekly iron administration for the prevention of ID anemia (IDA) in infants. Population and methods. Randomized, controlled clinical trial. Infants seen at a public health center, without anemia at 3 months of age, were randomized into 3 groups: daily supplementation (1 mg/kg/day), weekly supplementation (4 mg/kg/week), or no supplementation (control group with exclusive breastfeeding [EB]). Anemia and ID were assessed at 3 and 6 months old. Adherence and adverse events were recorded. Data were analyzed using the R software, version 4.0.3. Results. A total of 227 infants participated. At 6 months, the group of infants with EB without supplementation (control) had a higher prevalence of ID and IDA than the intervention groups (daily and weekly). ID: 40.5% versus 13.5% and 16.7% (p = 0.002); IDA: 33.3% versus 7.8% and 10% (p < 0.001). There were no differences between the daily and weekly supplementation groups. There were also no differences in the percentage of high adherence to supplementation (50.6% daily versus 57.1% weekly) or adverse events. Conclusions. No significant differences in effectiveness were observed between daily and weekly administration for the prevention of infant IDA.

Introducción. La deficiencia de hierro (DH) es la carencia nutricional más prevalente y la principal causa de anemia en lactantes. Existe consenso en la suplementación diaria con hierro como estrategia de prevención; también se demostró que la suplementación semanal es eficaz, pero la evidencia en lactantes es escasa. El objetivo fue comparar la efectividad de la administración diaria de hierro frente a la semanal para la prevención de la anemia por DH del lactante. Población y métodos. Ensayo clínico controlado y aleatorizado. Lactantes atendidos en un centro de salud público, sin anemia a los 3 meses de edad, aleatorizados en tres grupos: suplementación diaria (1 mg/kg/día), semanal (4 mg/kg/semana) o sin suplementación (grupo control con lactancia materna exclusiva [LME]). Se evaluó anemia y DH a los 3 y 6 meses. Se registró grado de adherencia y efectos adversos. Los datos se analizaron con el software R versión 4.0.3. Resultados. Participaron 227 lactantes. A los 6 meses el grupo de lactantes con LME sin suplementación (control) presentó prevalencias de DH y anemia por DH (ADH) mayores que los grupos intervenidos (diario y semanal). DH: 40,5 % vs. 13,5 % y 16,7 % (p = 0,002); ADH: 33,3 % vs. 7,8 % y 10 % (p < 0,001). No hubo diferencias entre los grupos diario y semanal. Tampoco hubo diferencias en el porcentaje de alta adherencia a la suplementación (50,6 % diaria vs. 57,1 % semanal), ni en los efectos adversos. Conclusiones. No se hallaron diferencias significativas en la efectividad entre la administración diaria y semanal para la prevención de ADH del lactante.

Exposición ambiental a plomo y biomarcadores de estrés oxidativo en niños sanos de La Plata, Argentina / Environmental exposure to lead and oxidative stress biomarkers among healthy children in La Plata, Argentina

Introducción. La exposición ambiental a plomo (Pb) aún constituye un problema de salud pública, particularmente para los niños. El estrés oxidativo podría representar un mecanismo primario asociado a su toxicidad. El objetivo del presente estudio fue determinar los niveles de Pb en sangre (Pb-S) en niños de 1 a 6 años de La Plata y alrededores con exposición ambiental, y su relación con biomarcadores de estrés oxidativo. Población y métodos. Estudio analítico de corte transversal. Se evaluaron niños clínicamente sanos de 1 a 6 años. Se determinaron los niveles de Pb-S, las actividades de enzimas antioxidantes y el grado de peroxidación lipídica. Se utilizó el paquete estadístico R versión 3.5.1. Resultados. Participaron 131 niños, mediana de edad 2,33 años. La media geométrica de los niveles de Pb-S fue 1,90 µg/dL; el 32 % presentó plombemias cuantificables y el 3 %, niveles ≥5 µg/dL (referencia internacional). Al comparar los biomarcadores de estrés oxidativo según los niveles de Pb-S, solo se observó diferencia significativa entre las medianas de las sustancias reactivas al ácido tiobarbitúrico (TBARS): 12,0 versus 10,0 nmol MDA/mL plasma; p = 0,02. Asimismo, la correlación entre las plombemias y las TBARS fue positiva (r = 0,24; p = 0,012). Conclusiones. La mayoría de los niños mostraron niveles de Pb-S menores a los límites recomendados por agencias internacionales, que si bien, no producen alteraciones en la actividad de enzimas antioxidantes, sí inducen peroxidación lipídica. Estos resultados reflejan la utilidad de este biomarcador como una herramienta diagnóstica temprana para evaluar los efectos subtóxicos del Pb.

Introduction. Environmental exposure to lead is still a major public health problem, especially in children. Oxidative stress may be a primary mechanism associated with toxicity. Theobjective of this study was to measure blood lead levels (BLLs) in children aged 1 to 6 years expos to lead in La Plata and suburban areas and their relation to oxidative stress biomarkers. Population and methods. Cross-sectional,analytical study. Clinically healthy children aged1 to 6 years were analyzed. BLLs, antioxidant enzyme activity, and extent of lipid peroxidation were measured. The statistical softwarepackage R, version 3.5.1, was used. Results. A total of 131 children participated; their median age was 2.33 years. The geometric mean of BLLs was 1.90 µg/dL; 32% showed a measurable BLL and 3%, BLLs ≥ 5 µg/dL (international reference). The comparison ofoxidative stress biomarkers based on BLshowed a significant difference in median thiobarbituric acid reactive substances (TBARS):12.0 versus 10.0 nmol MDA/mL of plasma;p = 0.02. In addition, the correlation between BLLs and TBARS was positive (r = 0.24; p = 0.012 Conclusions. Most children had a BLL below the limit recommended by international agencies; although such BLLs do not affantioxidant enzyme activity, they can induce lipid peroxidation. These results demonstrate theusefulness of this biomarker as an early diagnosistool to assess subtoxic lead effects.

Environmental exposure to lead and oxidative stress biomarkers among healthy children in La Plata, Argentina. / Exposición ambiental a plomo y biomarcadores de estrés oxidativo en niños sanos de La Plata, Argentina.

INTRODUCTION: Environmental exposure to lead is still a major public health problem, especially in children. Oxidative stress may be a primary mechanism associated with toxicity. The objective of this study was to measure blood lead levels (BLLs) in children aged 1 to 6 years exposed to lead in La Plata and suburban areas and their relation to oxidative stress biomarkers. POPULATION AND METHODS: Cross-sectional, analytical study. Clinically healthy children aged 1 to 6 years were analyzed. BLLs, antioxidant enzyme activity, and extent of lipid peroxidation were measured. The statistical software package R, version 3.5.1, was used. RESULTS: A total of 131 children participated; their median age was 2.33 years. The geometric mean of BLLs was 1.90 µg/dL; 32% showed a measurable BLL and 3%, BLLs ≥ 5 µg/dL (international reference). The comparison of oxidative stress biomarkers based on BLLs showed a significant difference in median thiobarbituric acid reactive substances (TBARS): 12.0 versus 10.0 nmol MDA/mL of plasma; p = 0.02. In addition, the correlation between BLLs and TBARS was positive (r = 0.24; p = 0.012). CONCLUSIONS: Most children had a BLL below the limit recommended by international agencies; although such BLLs do not affect antioxidant enzyme activity, they can induce lipid peroxidation. These results demonstrate the usefulness of this biomarker as an early diagnosis tool to assess subtoxic lead effects.

Introducción. La exposición ambiental a plomo (Pb) aún constituye un problema de salud pública, particularmente para los niños. El estrés oxidativo podría representar un mecanismo primario asociado a su toxicidad. El objetivo del presente estudio fue determinar los niveles de Pb en sangre (Pb-S) en niños de 1 a 6 años de La Plata y alrededores con exposición ambiental, y su relación con biomarcadores de estrés oxidativo. Población y métodos. Estudio analítico de corte transversal. Se evaluaron niños clínicamente sanos de 1 a 6 años. Se determinaron los niveles de Pb-S, las actividades de enzimas antioxidantes y el grado de peroxidación lipídica. Se utilizó el paquete estadístico R versión 3.5.1. Resultados. Participaron 131 niños, mediana de edad 2,33 años. La media geométrica de los niveles de Pb-S fue 1,90 µg/dL; el 32 % presentó plombemias cuantificables y el 3 %, niveles ≥5 µg/dL (referencia internacional). Al comparar los biomarcadores de estrés oxidativo según los niveles de Pb-S, solo se observó diferencia significativa entre las medianas de las sustancias reactivas al ácido tiobarbitúrico (TBARS): 12,0 versus 10,0 nmol MDA/mL plasma; p = 0,02. Asimismo, la correlación entre las plombemias y las TBARS fue positiva (r = 0,24; p = 0,012). Conclusiones. La mayoría de los niños mostraron niveles de Pb-S menores a los límites recomendados por agencias internacionales, que si bien, no producen alteraciones en la actividad de enzimas antioxidantes, sí inducen peroxidación lipídica. Estos resultados reflejan la utilidad de este biomarcador como una herramienta diagnóstica temprana para evaluar los efectos subtóxicos del Pb.

Neurodevelopmental assessment of infants born to mothers with hypertensive disorder of pregnancy at six months of age.

Infant neurodevelopment is a complex process which may be affected by different events during pregnancy, such as hypertensive disorders of pregnancy (HDP). We conducted a prospective cohort study to compare the prevalence of neurodevelopmental disorders in infants born to mothers with and without HDP at six months of age. Participants attended the Health Observatory of Instituto de Desarrollo e Investigaciones Pediátricas "Prof. Dr. Fernando E. Viteri" during 2018 and 2019. Infant neurodevelopment was assessed with the Bayley Scales of Infant and Toddler Development-Third Edition (Bayley-III). Data were analyzed using Chi-square, Student's t-test and Mann-Whitney test. Of the 132 participating infants, 68 and 64 were born to mothers with and without HDP, respectively. At six months, the prevalence of risk of neurodevelopmental delay was significantly higher in infants born to mothers with than without HDP (27.9% vs. 9.4%; p = 0.008) (odds ratio, 3.71; 95% confidence interval, 1.30; 12.28). In conclusion, infants born to mothers with HDP had three times increased risk of neurodevelopmental delay at six months of age.

Functional requirements of protein kinases and phosphatases in the development of the Drosophila melanogaster wing.

Protein kinases and phosphatases constitute a large family of conserved enzymes that control a variety of biological processes by regulating the phosphorylation state of target proteins. They play fundamental regulatory roles during cell cycle progression and signaling, among other key aspects of multicellular development. The complement of protein kinases and phosphatases includes approximately 326 members in Drosophila, and they have been the subject of several functional screens searching for novel components of signaling pathways and regulators of cell division and survival. These approaches have been carried out mostly in cell cultures using RNA interference to evaluate the contribution of each protein in different functional assays and have contributed significantly to assign specific roles to the corresponding genes. In this work, we describe the results of an evaluation of the Drosophila complement of kinases and phosphatases using the wing as a system to identify their functional requirements in vivo. We also describe the results of several modifying screens aiming to identify among the set of protein kinases and phosphatases additional components or regulators of the activities of the epidermal growth factor and insulin receptors signaling pathways.

Genome-wide phenotypic RNAi screen in the Drosophila wing: phenotypic description of functional classes.

The Drosophila genome contains approximately 14,000 protein-coding genes encoding all the necessary information to sustain cellular physiology, tissue organization, organism development, and behavior. In this manuscript, we describe in some detail the phenotypes in the adult fly wing generated after knockdown of approximately 80% of Drosophila genes. We combined this phenotypic description with a comprehensive molecular classification of the Drosophila proteins into classes that summarize the main expected or known biochemical/functional aspect of each protein. This information, combined with mRNA expression levels and in situ expression patterns, provides a simplified atlas of the Drosophila genome, from housekeeping proteins to the components of the signaling pathways directing wing development, that might help to further understand the contribution of each gene group to wing formation.

Genome-wide phenotypic RNAi screen in the Drosophila wing: global parameters.

We have screened a collection of UAS-RNAi lines targeting 10,920 Drosophila protein-coding genes for phenotypes in the adult wing. We identified 3653 genes (33%) whose knockdown causes either larval/pupal lethality or a mutant phenotype affecting the formation of a normal wing. The most frequent phenotypes consist of changes in wing size, vein differentiation, and patterning, defects in the wing margin and in the apposition of the dorsal and ventral wing surfaces. We also defined 16 functional categories encompassing the most relevant aspect of each protein function and assigned each Drosophila gene to one of these functional groups. This allowed us to identify which mutant phenotypes are enriched within each functional group. Finally, we used previously published gene expression datasets to determine which genes are or are not expressed in the wing disc. Integrating expression, phenotypic and molecular information offers considerable precision to identify the relevant genes affecting wing formation and the biological processes regulated by them.

Contribution of enriched wheat flour and flour products to iron requirements in children aged 6 months to 7 years. / Contribución de la harina de trigo enriquecida y derivados a los requerimientos de hierro en niños de 6 meses a 7 años.

INTRODUCTION: Wheat flour enrichment is a public health strategy recommended to prevent micronutrient deficiencies, including iron deficiency. The objective of this study was to determine iron content in enriched wheat flour and flour products and their contribution to nutritional recommendations for children. POPULATION AND METHODS: Observational, analytical, cross-sectional study based on the total diet study method. Enriched wheat flour (as per Law no. 25630) and the most frequently consumed flour products were analyzed. Products were selected using a questionnaire on the frequency of food intake and a 24-hour recall interview with the parents of children aged 6 months to 7 years. Food iron levels were determined based on atomic absorption spectrometry and their contribution to the estimated average requirement was assessed. RESULTS: Enriched flour and flour products showed the expected iron amount, except for French bread and breadcrumbs. The contribution of studied products to iron requirements was 7 % in children aged 6 months to 1 year, 81 % in those aged 1-3 years, and 45 % in those older than 4 years. CONCLUSIONS: Except for French bread and breadcrumbs, studied flour and flour products showed the expected enrichment level. The consumption of this type of food does not provide significant amounts of iron to infants, but it does to children older than 1 year.

Introducción. El enriquecimiento de la harina de trigo es una de las estrategias de salud pública recomendadas para prevenir las deficiencias de micronutrientes, entre ellos el hierro. El objetivo de este trabajo fue determinar el contenido de hierro en harina de trigo enriquecida y sus derivados, y la contribución de estos a las recomendaciones nutricionales en niños. Población y métodos. Estudio observacional, analítico, de corte transversal, basado en la metodología de estudio de dieta total. Se analizaron la harina de trigo enriquecida (según la ley 25630) y sus derivados más consumidos. Para seleccionar los alimentos, se realizó un cuestionario de frecuencia de consumo y recordatorio de 24 horas a los padres de niños con edades entre 6 meses y 7 años. Se determinó la concentración de hierro en los alimentos mediante absorción atómica y se evaluó su contribución al requerimiento promedio estimado. Resultados. La harina enriquecida y sus derivados tuvieron la cantidad de hierro esperada, excepto el pan francés y el pan rallado. La contribución a los requerimientos de hierro de los alimentos evaluados fue el 7 % en niños de 6 meses a 1 año, el 81 % en el grupo de 1 a 3 años y el 45 % en los mayores de 4 años. Conclusiones. Excepto el pan francés y el pan rallado, las harinas y sus derivados analizados presentaron el nivel de enriquecimiento esperado. El consumo de estos alimentos no aporta cantidades significativas de hierro en los lactantes, pero sí en los niños mayores de 1 año.

Contribución de la harina de trigo enriquecida y derivados a los requerimientos de hierro en niños de 6 meses a 7 años / Contribution of enriched wheat flour and flour products to iron requirements in children aged 6 months to 7 year

Introducción. El enriquecimiento de la harina de trigo es una de las estrategias de salud pública recomendadas para prevenir las deficiencias de micronutrientes, entre ellos el hierro. El objetivo de este trabajo fue determinar el contenido de hierro en harina de trigo enriquecida y sus derivados, y la contribución de estos a las recomendaciones nutricionales en niños. Población y métodos. Estudio observacional, analítico, de corte transversal, basado en la metodología de estudio de dieta total. Se analizaron la harina de trigo enriquecida (según la ley 25630) y sus derivados más consumidos. Para seleccionar los alimentos, se realizó un cuestionario de frecuencia de consumo y recordatorio de 24 horas a los padres de niños con edades entre 6 meses y 7 años. Se determinó la concentración de hierro en los alimentos mediante absorción atómica y se evaluó su contribución al requerimiento promedio estimado. Resultados. La harina enriquecida y sus derivados tuvieron la cantidad de hierro esperada, excepto el pan francés y el pan rallado. La contribución a los requerimientos de hierro de los alimentos evaluados fue el 7 % en niños de 6 meses a 1 año, el 81 % en el grupo de 1 a 3 años y el 45 % en los mayores de 4 años. Conclusiones. Excepto el pan francés y el pan rallado, las harinas y sus derivados analizados presentaron el nivel de enriquecimiento esperado. El consumo de estos alimentos no aporta cantidades significativas de hierro en los lactantes, pero sí en los niños mayores de 1 año.

Introduction. Wheat flour enrichment is a public health strategy recommended to prevent micronutrient deficiencies, including iron deficiency. The objective of this study was to determine iron content in enriched wheat flour and flour products and their contribution to nutritional recommendations for children. Population and methods. Observational, analytical, cross-sectional study based on the total diet study method. Enriched wheat flour (as per Law no. 25630) and the most frequently consumed flour products were analyzed. Products were selected using a questionnaire on the frequency of food intake and a 24-hour recall interview with the parents of children aged 6 months to 7 years. Food iron levels were determined based on atomic absorption spectrometry and their contribution to the estimated average requirement was assessed. Results. Enriched flour and flour products showed the expected iron amount, except for French bread and breadcrumbs. The contribution of studied products to iron requirements was 7 % in children aged 6 months to 1 year, 81 % in those aged 1-3 years, and 45 % in those older than 4 years. Conclusions. Except for French bread and breadcrumbs, studied flour and flour products showed the expected enrichment level. The consumption of this type of food does not provide significant amounts of iron to infants, but it does to children older than 1 year.

Multitemporal optical and radar metrics for wetland mapping at national level in Albania.

Wetlands are highly dynamic, with many natural and anthropogenic drivers causing seasonal, periodic or permanent changes in their structure and composition. Thus, it is necessary to use time series of images for accurate classifications and monitoring. We used all available Sentinel-1 and Sentinel-2 images to produce a national wetlands map for Albania. We derived different indices and temporal metrics and investigated their impacts and synergies in terms of mapping accuracy. Best results were achieved when combining Sentinel-1 with Sentinel-2 and its derived indices. We reduced systematic errors and increased the thematic resolution using morphometric characteristics and knowledge-based rules, achieving an overall accuracy of 82%. Results were also validated against field inventories. This methodology can be reproducible to other countries and can be made operational for an integrated planning that considers the food, water, and energy nexus.

Ras2, the TC21/R-Ras2 Drosophila homologue, contributes to insulin signalling but is not required for organism viability.

Ras1 (Ras85D) and Ras2 (Ras64B) are the Drosophila orthologs of human H-Ras/N-Ras/K-Ras and R-Ras1-3 genes, respectively. The function of Ras1 has been thoroughly characterised during Drosophila embryonic and imaginal development, and it is associated with coupling activated trans-membrane receptors with tyrosine kinase activity to their downstream effectors. In this capacity, Ras1 binds and is required for the activation of Raf. Ras1 can also interact with PI3K, and it is needed to achieve maximal levels of PI3K signalling in specific cellular settings. In contrast, the function of the unique Drosophila R-Ras member (Ras2/Ras64B), which is more closely related to vertebrate R-Ras2/TC21, has been only studied through the use of constitutively activated forms of the protein. This pioneering work identified a variety of phenotypes that were related to those displayed by Ras1, suggesting that Ras1 and Ras2 might have overlapping activities. Here we find that Ras2 can interact with PI3K and Raf and activate their downstream effectors Akt and Erk. However, and in contrast to mutants in Ras1, which are lethal, null alleles of Ras2 are viable in homozygosis and only show a phenotype of reduced wing size and extended life span that might be related to reduced Insulin receptor signalling.

Deficiencia de vitamina A y factores asociados en niños preescolares de la periferia de la ciudad de La Plata, Buenos Aires / Vitamin A deficiency and associated factors in preschoolers from the outskirts of La Plata, Buenos Aires

Introducción. La deficiencia de vitamina A (DVA) ha sido reconocida como un importante problema de salud pública en países en vías de desarrollo. Los niños en edad preescolar son grupos de riesgo en poblaciones vulnerables. El objetivo fue determinar la prevalencia de DVA y los factores asociados en una muestra de niños de edad preescolar. Material y métodos. Estudio de corte transversal que incluyó a niños de 1 a 6 años beneficiarios de planes sociales, atendidos en centros de atención primaria de la periferia de la ciudad de la Plata, Buenos Aires. Se determinó el contenido de vitamina A midiendo retinol sérico, por cromatografía líquida, y se registraron parámetros antropométricos e ingesta alimentaria. Se utilizó un modelo de regresión logística multinomial para evaluar la asociación entre las variables. Resultados. Se analizaron datos de 624 niños. La media geométrica de retinol fue 23,8 pg/dl (IC 95 %: 23,3-24,3). Las prevalencias de DVA y riesgo de DVA fueron 24,3 % y 57,4 %, respectivamente. Los niveles de retinol fueron significativamente menores en niños varones, con bajo peso y aquellos con bajo consumo (menor del primer tercilo de distribución). El análisis multivariable mostró asociación significativa entre DVA y el sexo masculino (OR: 1,93; IC 95 %: 1,15-3,24) y con el bajo consumo (OR: 1,48; IC 95 %: 1,15-2,62). Conclusión. La prevalencia de DVA hallada (24,3 %) constituye un importante problema de salud pública en esta población. Los factores asociados a dicha deficiencia fueron el sexo masculino y el bajo consumo.

Introduction. Vitamin A deficiency (VAD) has been recognized as an important public health problem in developing countries. Preschoolers account for risk groups within vulnerable populations. The objective of this study was to determine the prevalence of VAD and associated factors in a sample of preschoolers. Material and methods. Cross-sectional study with children aged 1-6 years receiving social assistance and seen at primary health care centers in the outskirts of the city of La Plata, Buenos Aires. Vitamin A levels were determined by measuring serum retinol with a liquid chromatography; anthropometric parameters and dietary intake were recorded. A multinomial logistic regression model was used to assess the association among outcome measures. Results. Data from 624 children were analyzed. The geometric mean of retinol was 23.8 pg/dL (95 % CI: 23.3-24.3). The prevalence of VAD and the risk for VAD were 24.3 % and 57.4 %, respectively. Retinol levels were significantly lower among boys, low-weight children, and those with low intake (below the first tertile of distribution). The multivariate analysis showed a significant association between VAD and male sex (odds ratio: 1.93; 95 % CI: 1.15-3.24) and between VAD and low intake (odds ratio: 1.48; 95 % CI: 1.15-2.62). Conclusion. The prevalence of VAD (24.3 %) is a major public health problem in this population. VAD-associated factors were male sex and low vitamin A intake.

Vitamin A deficiency and associated factors in preschoolers from the outskirts of La Plata, Buenos Aires. / Deficiencia de vitamina A y factores asociados en niños preescolares de la periferia de la ciudad de La Plata, Buenos Aires.

INTRODUCTION: Vitamin A deficiency (VAD) has been recognized as an important public health problem in developing countries. Preschoolers account for risk groups within vulnerable populations. The objective of this study was to determine the prevalence of VAD and associated factors in a sample of preschoolers. MATERIALS AND METHODS: Cross-sectional study with children aged 1-6 years receiving social assistance and seen at primary health care centers in the outskirts of the city of La Plata, Buenos Aires. Vitamin A levels were determined by measuring serum retinol with a liquid chromatography; anthropometric parameters and dietary intake were recorded. A multinomial logistic regression model was used to assess the association among outcome measures. RESULTS: Data from 624 children were analyzed. The geometric mean of retinol was 23.8 pg/dL (95 % CI: 23.3-24.3). The prevalence of VAD and the risk for VAD were 24.3 % and 57.4 %, respectively. Retinol levels were significantly lower among boys, low-weight children, and those with low intake (below the first tertile of distribution). The multivariate analysis showed a significant association between VAD and male sex (odds ratio: 1.93; 95 % CI: 1.15-3.24) and between VAD and low intake (odds ratio: 1.48; 95 % CI: 1.15-2.62). CONCLUSION: The prevalence of VAD (24.3 %) is a major public health problem in this population. VAD-associated factors were male sex and low vitamin A intake.

Introducción. La deficiencia de vitamina A (DVA) ha sido reconocida como un importante problema de salud pública en países en vías de desarrollo. Los niños en edad preescolar son grupos de riesgo en poblaciones vulnerables. El objetivo fue determinar la prevalencia de DVA y los factores asociados en una muestra de niños de edad preescolar. Material y métodos. Estudio de corte transversal que incluyó a niños de 1 a 6 años beneficiarios de planes sociales, atendidos en centros de atención primaria de la periferia de la ciudad de la Plata, Buenos Aires. Se determinó el contenido de vitamina A midiendo retinol sérico, por cromatografía líquida, y se registraron parámetros antropométricos e ingesta alimentaria. Se utilizó un modelo de regresión logística multinomial para evaluar la asociación entre las variables. Resultados. Se analizaron datos de 624 niños. La media geométrica de retinol fue 23,8 pg/dl (IC 95 %: 23,3-24,3). Las prevalencias de DVA y riesgo de DVA fueron 24,3 % y 57,4 %, respectivamente. Los niveles de retinol fueron significativamente menores en niños varones, con bajo peso y aquellos con bajo consumo (menor del primer tercilo de distribución). El análisis multivariable mostró asociación significativa entre DVA y el sexo masculino (OR: 1,93; IC 95 %: 1,15-3,24) y con el bajo consumo (OR: 1,48; IC 95 %: 1,15-2,62). Conclusión. La prevalencia de DVA hallada (24,3 %) constituye un importante problema de salud pública en esta población. Los factores asociados a dicha deficiencia fueron el sexo masculino y el bajo consumo.