ABSTRACT
We performed a histological and quantitative study of iron in archaeological maize seeds from prehispanic times recovered from Tarapacá, Atacama Desert. Also, we examined iron distribution changes at the cell level in embryos from ancient versus new varieties of maize. Our results show a progressive decrease in iron concentration from the oldest maize to modern specimens. We interpret the results as an effect of prehispanic agriculture over the micronutrient composition of maize.
ABSTRACT
RESUMEN Introducción: Hasta la fecha no se ha podido establecer un consenso para definir de forma universal el Síndrome Metabólico (SM) en niños y adolescentes. En Paraguay, no ha sido documentada la variación de la frecuencia de SM en niños y adolescentes de acuerdo a las diferentes definiciones propuestas en la literatura. Objetivo: Determinar la frecuencia de Síndrome Metabólico en niños y adolescentes de una escuela de la ciudad de Asunción utilizando 3 diferentes definiciones. Materiales y Métodos: Se realizó un estudio de corte transversal en niños y adolescentes (9-13 años). Se recolectaron datos demográficos y mediciones antropométricas. Se extrajeron muestras de sangre en ayunas. Se analizó el colesterol total, triglicéridos, HDL-colesterol, LDL-colesterol y se midió la presión arterial. La frecuencia de SM se estimó a partir de las definiciones modificadas de la Federación Internacional de Diabetes (IDFmod), Programa Nacional de Educación sobre Colesterol (NCEPmod) y De Ferranti. El protocolo de estudio fue aprobado por el comité de ética de la FCQ-UNA Cod 340/17. Resultados: Se analizaron datos de 76 niños y adolescentes (el 56% de sexo masculino), cuya edad promedio fue de 10,5 ±1,1 años. El 54% presentó sobrepeso y obesidad. La frecuencia de SM fue 5,26% según IDFmod, 7,89% según NCEPmod y 22,37% de según De Ferranti. Conclusión: La frecuencia de SM fue mayor al emplear la definición propuesta por De Ferranti. Utilizar definiciones cuyos puntos de corte son más estrictos podría tener un efecto en términos preventivos al detectar precozmente a los niños y adolescentes en riesgo.
ABSTRACT Introduction: To date it has not been possible to establish a consensus to universally define the Metabolic Syndrome (MS) in children and adolescents. In Paraguay, the variation in the frequency of MS in children and adolescents has not been documented according to the different definitions proposed in the literature. Objective: To determine the frequency of Metabolic Syndrome in children and adolescents of a school in the city of Asunción using 3 different definitions. Materials and Methods: This was a cross-sectional study that was carried out in children and adolescents (9-13 years). Demographic data and anthropometric measurements were collected. Fasting blood samples were drawn. Total cholesterol, triglycerides, HDL-cholesterol, LDL-cholesterol were analyzed and blood pressure was measured. The frequency of MS was estimated from the modified definitions of the International Diabetes Federation (IDFmod), National Cholesterol Education Program (NCEPmod) and De Ferranti. The study protocol was approved by the ethics committee of the FCQ-UNA Cod 340/17. Results: Data from 76 children and adolescents (56% male), whose average age was 10.5 ± 1.1 years, were analyzed. 54% were overweight and obese. The frequency of MS was 5.26% according to IDFmod, 7.89% according to NCEPmod and 22.37% according to De Ferranti. Conclusion: The frequency of MS was higher when using the definition proposed by De Ferranti. Using definitions whose cut-off points are stricter could have a preventive effect by early detection of at-risk children and adolescents.
ABSTRACT
Iron (Fe) is an essential micronutrient for plant growth and development. Any defects in the maintenance of Fe homeostasis will alter plant productivity and the quality of their derived products. In Arabidopsis (Arabidopsis thaliana), the transcription factor ILR3 plays a central role in controlling Fe homeostasis. In this study, we identified bHLH121 as an ILR3-interacting transcription factor. Interaction studies showed that bHLH121 also interacts with the three closest homologs of ILR3 (i.e., basic-helix-loop-helix 34 [bHLH34], bHLH104, and bHLH115). bhlh121 loss-of-function mutants displayed severe defects in Fe homeostasis that could be reverted by exogenous Fe supply. bHLH121 acts as a direct transcriptional activator of key genes involved in the Fe regulatory network, including bHLH38, bHLH39, bHLH100, bHLH101, POPEYE, BRUTUS, and BRUTUS LIKE1, as well as IRONMAN1 and IRONMAN2 In addition, bHLH121 is necessary for activating the expression of transcription factor gene FIT in response to Fe deficiency via an indirect mechanism. bHLH121 is expressed throughout the plant body, and its expression is not affected by Fe availability. By contrast, Fe availability affects the cellular localization of bHLH121 protein in roots. Altogether, these data show that bHLH121 is a regulator of Fe homeostasis that acts upstream of FIT in concert with ILR3 and its closest homologs.
Subject(s)
Arabidopsis Proteins/metabolism , Arabidopsis/metabolism , Basic Helix-Loop-Helix Transcription Factors/metabolism , Homeostasis/physiology , Iron/metabolism , Transcription Factors/metabolism , Arabidopsis/genetics , Arabidopsis Proteins/genetics , Basic Helix-Loop-Helix Leucine Zipper Transcription Factors , Basic Helix-Loop-Helix Transcription Factors/genetics , Gene Expression Regulation, Plant , Gene Knockout Techniques , Gene Regulatory Networks , Homeostasis/genetics , Hydroponics , Nuclear Proteins , Plant Roots/genetics , Plant Roots/metabolism , Plants, Genetically Modified , Transcription Factors/genetics , Transcriptome , Ubiquitin-Protein LigasesABSTRACT
Como parte del ciclo biogeoquímico, el fluoruro del suelo puede disolverse e ingresar al agua. La Organización Mundial de la Salud y la Norma Paraguaya NP 24 001 80 establecen una concentración máxima de 1,5 mg.L-1 de fluoruro en agua de consumo, pudiendo producir fluorosis cuando es elevada, tal como se encontró en niños residentes de Loreto. Estudios indican que la exposición al fluoruro concomitante al déficit de calcio puede agravar la pérdida de masa ósea, causando fragilidad y fluorosis esquelética. Además, se demostró mediante bioensayos en ratones que el exceso de fluoruro reduce la concentración de calcio sérico, por lo que el objetivo del estudio descriptivo con componente analítico fue elaborar un mapa de distribución espacial de fluoruro del agua subterránea de Loreto y relacionar con la calcemia en niños. Se determinó la concentración de fluoruro en muestras de veintitrés pozos de agua subterránea y el calcio sérico de dieciocho niños en edad escolar, ambos por método normalizado. Se identificaron dos pozos con concentraciones superiores al máximo permitido y en 61% de los niños el calcio sérico fue inferior al valor de referencia. Se encontró una correlación débil entre las variables (r = 0,212). El estudio proporciona información relevante sobre sitios con elevadas concentraciones de fluoruro lo que representa un riesgo para la salud pues aun con ingesta adecuada de calcio, los niños presentaron hipocalcemia. Sería importante incluir en estudios posteriores factores no abordados en esta investigación para una evaluación más completa del riesgo de la población expuesta(AU)
As part of the biogeochemical cycle, soil fluoride can dissolve and accumulate in groundwater. World Health Organization and the Paraguayan Standard NP 24 001 80 establishes of 1.5 mg.L-1 of fluoride in drinking water, which can produce fluorosis when it is higher, as it has been found in children of Loreto. Studies indicate that exposure to fluoride concomitant with calcium deficit may aggravate bone loss, causing frailty and skeletal fluorosis. In addition, it was demonstrated through bioassays in mice that excess fluoride reduces serum calcium concentration, the objective of the descriptive study with the analytical component has become a spatial distribution map of Loreto groundwater and related to calcemia in children. The fluoride concentration was determined in samples from twenty-three groundwater wells and serum calcium from eighteen school-age children, both by standard method. Two points were identified with levels above the maximum allowed and in 61% of the children the serum calcium was lower than the reference value. We found a weak correlation between the variables (r = 0.212). It would be important to include in later studies factors not addressed in this research for a more complete risk assessment of the exposed population(AU)
Subject(s)
Humans , Child , Groundwater/chemistry , Calcium/blood , Fluorides/analysis , Residence Characteristics , Water WellsABSTRACT
Seeds accumulate iron during embryo maturation stages of embryogenesis. Using Arabidopsis thaliana as model plant, it has been described that mature embryos accumulate iron within a specific cell layer, the endodermis. This distribution pattern was conserved in most of the analyzed members from Brassicales, with the exception of the basal Vasconcellea pubescens that also showed elevated amounts of iron in cortex cells. To determine whether the V. pubescens iron distribution was indicative of a wider pattern in non-Brassicales Eudicotyledoneae, we studied iron distribution pattern in different embryos belonging to plant species from different Orders from Eudicotyledoneae and one basal from Magnoliidae. The results obtained indicate that iron distribution in A. thaliana embryo is an extreme case of apomorphic character found in Brassicales, not-extensive to the rest of Eudicotyledoneae.
ABSTRACT
Iron is an essential micronutrient for plants. Little is know about how iron is loaded in embryo during seed development. In this article we used Perls/DAB staining in order to reveal iron localization at the cellular and subcellular levels in different Brassicaceae seed species. In dry seeds of Brassica napus, Nasturtium officinale, Lepidium sativum, Camelina sativa, and Brassica oleracea iron localizes in vacuoles of cells surrounding provasculature in cotyledons and hypocotyl. Using B. napus and N. officinale as model plants we determined where iron localizes during seed development. Our results indicate that iron is not detectable by Perls/DAB staining in heart stage embryo cells. Interestingly, at torpedo development stage iron localizes in nuclei of different cells type, including integument, free cell endosperm and almost all embryo cells. Later, iron is detected in cytoplasmic structures in different embryo cell types. Our results indicate that iron accumulates in nuclei in specific stages of embryo maturation before to be localized in vacuoles of cells surrounding provasculature in mature seeds.