RESUMEN
OBJECTIVES: To prospectively evaluate the associations of early and current life factors, including gestational age and fetal growth restriction in preterm-born subjects, on cardiovascular health including measures of central and peripheral blood pressure and arterial stiffness and assess cardiovascular changes before and after acute exercise in preterm- and term-born school-aged children. STUDY DESIGN: From 240 children, aged 7-12 years, 204 (141 preterm-born and 63 term-born) had satisfactory data. An oscillometric device recorded cardiovascular measures before and after cycle ergometer exercise testing. Data were analyzed with multivariable linear regression and mediation. RESULTS: Central systolic blood pressure (SBP) was 6.4 mmHg (95% CI, 1.2, 11.6) higher in preterm-born children with fetal growth restriction and 3.4 mmHg (0.02, 6.8) higher in those without fetal growth restriction when compared with term controls. Augmentation index was 4.1% (0.7, 7.4) higher in the preterm fetal growth restriction group when compared with those without fetal growth restriction but was similar between the latter group and term controls. Regression modelling showed gestational age, female sex, and antenatal smoking, but not fetal growth restriction, were significantly associated with SBP. In contrast, fetal growth restriction and fat mass index, but not gestation, were significantly associated with augmentation index. Cardiovascular exercise responses were similar between all 3 groups studied. CONCLUSIONS: Our data show the differential associations of prematurity and fetal growth restriction on central SBP and augmentation index. Cardiovascular responses to exercise were similar in all 3 groups. Preterm-born children with and without fetal growth restriction are at an increased risk of cardiovascular disease in adult life. TRIAL REGISTRATION: URL: https://www.clinicaltrialsregister.eu/ctr-search/trial/2015-003712-20/GB: RHiNO, EudraCT: 2015-003712-20.
Asunto(s)
Retardo del Crecimiento Fetal , Recien Nacido Prematuro , Recién Nacido , Adulto , Humanos , Femenino , Niño , Embarazo , Factores de Riesgo , Edad Gestacional , Presión Sanguínea/fisiologíaRESUMEN
OBJECTIVE: To evaluate how birth weight affects lung function measurements in childhood and adolescence in term-born children. STUDY DESIGN: We used data for white, term-born, singletons, from the Avon Longitudinal Study of Parents and Children to determine the association between birth weight and lung function at age 8-9 (n=4086) and 14-17 (n=2582) years. z-scores for lung function measures, adjusted for sex, height, and age, were modeled in terms of birth weight z-score adjusted for sex. In addition, gestation and head circumference then confounders (maternal smoking during pregnancy and social class) were added to the model. RESULTS: At age 8-9 years, birth weight z-scores were significantly associated with lung function z-scores (forced expiratory volume in 1 second, forced vital capacity [FVC], and forced mid-expiratory flow between 25% and 75% of FVC). These relationships essentially were unchanged when birth weight z-scores were further adjusted for gestation, head circumference, and confounders, except for forced mid-expiratory flow between 25% and 75% of FVC, which was no longer significant after we adjusted for head circumference and confounders. At age 14-17 years, the associations between adjusted birth-weight z-scores and spirometry z-scores were in general not significant. Estimated differences for forced expiratory volume in 1 second were 30 mL at ages 8-9 years and 33 mL at 14-17 years for 1 kg change in birth-weight standardized for gestation and sex. CONCLUSIONS: Birth weight is associated with lung function in term-born children at 8-9 years, but less so at 14-17 years, suggesting that birth weight influences lung function in early childhood but has lesser effect later in life.
Asunto(s)
Peso al Nacer , Pulmón/patología , Espirometría/métodos , Adolescente , Niño , Femenino , Volumen Espiratorio Forzado , Humanos , Estudios Longitudinales , Masculino , Pruebas de Función Respiratoria , Fumar , Clase Social , Nacimiento a Término , Población BlancaRESUMEN
OBJECTIVES: To compare objectively measured physical activity in 11- and 15-year-old children who were born preterm with term-born controls and related physical activity measures to lung function measures. STUDY DESIGN: We used data from the Avon Longitudinal Study of Parents and Children. We compared total physical activity, moderate-to-vigorous physical activity, and sedentary behavior between children born at 25-32, 33-34, 35-36, and 37-43 weeks' gestation at ages 11 and 15 years. At age 11 years, physical activity measures were correlated with lung spirometry recorded at age 7-9 years. RESULTS: Valid physical activity data at age 11 years were available for 5025, 197, 57, and 48 children born at 37-43, 35-36, 33-34, and 25-32 weeks' gestation, respectively. At age 15 years, valid physical activity data were available for 1829, 62, 32, and 24 children born at 37-43, 35-36, 33-34, and 25-32 weeks' gestation. Boys were more physically active than girls at both ages. There were no differences in total physical activity, moderate-to-vigorous physical activity, or sedentary behavior in children between the different gestation groups. Physical activity at age 11 years did not correlate with spirometry measures at age 7-9 years. CONCLUSIONS: Physical activity was similar for the different gestational groups and did not correlate with lung spirometry. Physical activity does not appear to be limited in preterm-born children despite lung function deficits noted in childhood.
Asunto(s)
Recien Nacido Prematuro/fisiología , Actividad Motora/fisiología , Acelerometría/métodos , Adolescente , Niño , Femenino , Estudios de Seguimiento , Edad Gestacional , Humanos , Masculino , Estudios Retrospectivos , EspirometríaRESUMEN
BACKGROUND: Populations of the Americas were founded by early migrants from Asia, and some have experienced recent genetic admixture. To better characterize the native and non-native ancestry components in populations from the Americas, we analyzed 815,377 autosomal SNPs, mitochondrial hypervariable segments I and II, and 36 Y-chromosome STRs from 24 Mesoamerican Totonacs and 23 South American Bolivians. RESULTS AND CONCLUSIONS: We analyzed common genomic regions from native Bolivian and Totonac populations to identify 324 highly predictive Native American ancestry informative markers (AIMs). As few as 40-50 of these AIMs perform nearly as well as large panels of random genome-wide SNPs for predicting and estimating Native American ancestry and admixture levels. These AIMs have greater New World vs. Old World specificity than previous AIMs sets. We identify highly-divergent New World SNPs that coincide with high-frequency haplotypes found at similar frequencies in all populations examined, including the HGDP Pima, Maya, Colombian, Karitiana, and Surui American populations. Some of these regions are potential candidates for positive selection. European admixture in the Bolivian sample is approximately 12%, though individual estimates range from 0-48%. We estimate that the admixture occurred ~360-384 years ago. Little evidence of European or African admixture was found in Totonac individuals. Bolivians with pre-Columbian mtDNA and Y-chromosome haplogroups had 5-30% autosomal European ancestry, demonstrating the limitations of Y-chromosome and mtDNA haplogroups and the need for autosomal ancestry informative markers for assessing ancestry in admixed populations.
Asunto(s)
Indio Americano o Nativo de Alaska/genética , Bolivia/etnología , ADN Mitocondrial , Emigración e Inmigración , Genética de Población , Humanos , México/etnología , Filogeografía , Polimorfismo de Nucleótido Simple , Selección GenéticaRESUMEN
To assess the relationship between mutations in Plasmodium falciparum dihydrofolate reductase (DHFR) and dihydropteroate synthase (DHPS) and clinical pyrimethamine-sulfadoxine resistance, polymerase chain reaction surveys and analyses for new mutations were conducted in four countries with increasing levels of pyrimethamine-sulfadoxine resistance: Mali, Kenya, Malawi, and Bolivia. Prevalence of mutations at DHFR codon 108 and a new mutation at DHPS 540 correlated with increased pyrimethamine-sulfadoxine resistance (P < .05). Mutations at DHFR 51, DHFR 59, and DHPS 437 correlated with resistance without achieving statistical significance. Mutations at DHFR 164 and DHPS 581 were common in Bolivia, where pyrimethamine-sulfadoxine resistance is widespread, but absent in African sites. Two new DHFR mutations, a point mutation at codon 50 and an insert at codon 30, were found only in Bolivia. DHFR and DHPS mutations occur in a progressive, stepwise fashion. Identification of specific sets of mutations causing in vivo drug failure may lead to the development of molecular surveillance methods for pyrimethamine-sulfadoxine resistance.
Asunto(s)
Antimaláricos/uso terapéutico , Dihidropteroato Sintasa/genética , Malaria Falciparum/parasitología , Plasmodium falciparum/genética , Pirimetamina/uso terapéutico , Sulfadoxina/uso terapéutico , Tetrahidrofolato Deshidrogenasa/genética , África/epidemiología , Secuencia de Aminoácidos , Animales , Antimaláricos/farmacología , Secuencia de Bases , Bolivia/epidemiología , Clonación Molecular , ADN Protozoario/análisis , ADN Protozoario/genética , Dihidropteroato Sintasa/metabolismo , Combinación de Medicamentos , Resistencia a Medicamentos , Humanos , Malaria Falciparum/tratamiento farmacológico , Malaria Falciparum/epidemiología , Malaria Falciparum/genética , Epidemiología Molecular , Datos de Secuencia Molecular , Estructura Molecular , Mutagénesis Insercional , Plasmodium falciparum/efectos de los fármacos , Plasmodium falciparum/enzimología , Mutación Puntual , Reacción en Cadena de la Polimerasa , Prevalencia , Pirimetamina/farmacología , Sulfadoxina/farmacología , Tetrahidrofolato Deshidrogenasa/química , Tetrahidrofolato Deshidrogenasa/metabolismoRESUMEN
OBJECTIVE: To determine whether successful deworming for 6 months in children with high levels of Ascaris improves physical growth. SUBJECTS: Two hundred twenty-eight children (mean age, 9.7 years) in a highland Indian town in Guatemala. DESIGN: Children were randomly assigned to receive albendazole or placebo at baseline and 12 weeks. Children and field workers were both blind to the group assignment. OUTCOME MEASURES: Children's heights, weights, and mid-upper-arm circumferences were measured at baseline and 12 and 24 weeks. Fecal egg counts were taken at 0, 2, 12, 14, and 24 weeks to estimate the helminth burden (eggs per gram of feces [epg]). RESULTS: Baseline helminth prevalences were Ascaris, 91%, and Trichuris, 82%. Ascaris intensities were high: half of the children had moderate burdens (10 000 to 50 000 epg), and 25% had heavy burdens ( > 50 000 epg). Trichuris burdens were light (72% < 1000 epg). The albendazole and placebo groups did not differ at baseline in epg, age, anthropometry, or socioeconomic status. The two rounds of treatment successfully reduced the Ascaris burdens but had less effect on Trichuris. At 6 months the treatment group showed a small gain in weight (0.18 kg) compared with the placebo group but no improvement in height or mid-upper-arm circumference. CONCLUSIONS: The successful removal of ascaris in a population of school-aged children with relatively high loads may have modest effects on weight gain. Ascaris is one of the most common infections in school-aged children, but its effect on the host may be less than that of other helminths.
Asunto(s)
Albendazol/uso terapéutico , Antihelmínticos/uso terapéutico , Ascariasis/complicaciones , Ascariasis/tratamiento farmacológico , Trastornos del Crecimiento/parasitología , Ascariasis/diagnóstico , Peso Corporal , Niño , Método Doble Ciego , Femenino , Estudios de Seguimiento , Trastornos del Crecimiento/diagnóstico , Guatemala , Humanos , Masculino , Prevalencia , EstudiantesRESUMEN
Intestinal helminths are among the most common infections in school-age children. Of 246 children, aged 7-12 years, attending school in rural Guatemala, 91% carried Ascaris lumbricoides and 82% carried Trichuris trichiura. These children were randomly assigned to receive either albendazole or placebo at 0 and 12 weeks in a 'double-blind' study of the effects of deworming on indicators of school performance. Albendazole successfully rid the children of Ascaris but it was less effective against Trichuris. The children's performance in tests of reading and vocabulary were measured at 0 and 24 weeks, the Peabody picture vocabulary test was given at 24 weeks, and attendance was measured throughout the school year. Comparison of the treated and placebo groups showed no positive effect of deworming. The treated children were largely free of Ascaris for at least 6 months, but during that period we could not detect any improvement in reading, vocabulary, or attendance. The effects of being Trichuris-free were not examined because of the limited effectiveness of albendazole against this worm at the dosage used.