RESUMO
The long-term health outcome of prenatal exposure to arsenic has been associated with increased mortality in human populations. In this study, the extent to which maternal arsenic exposure impacts gene expression in the newborn was addressed. We monitored gene expression profiles in a population of newborns whose mothers experienced varying levels of arsenic exposure during pregnancy. Through the application of machine learning-based two-class prediction algorithms, we identified expression signatures from babies born to arsenic-unexposed and -exposed mothers that were highly predictive of prenatal arsenic exposure in a subsequent test population. Furthermore, 11 transcripts were identified that captured the maximal predictive capacity to classify prenatal arsenic exposure. Network analysis of the arsenic-modulated transcripts identified the activation of extensive molecular networks that are indicative of stress, inflammation, metal exposure, and apoptosis in the newborn. Exposure to arsenic is an important health hazard both in the United States and around the world, and is associated with increased risk for several types of cancer and other chronic diseases. These studies clearly demonstrate the robust impact of a mother's arsenic consumption on fetal gene expression as evidenced by transcript levels in newborn cord blood.
Assuntos
Intoxicação por Arsênico/genética , Inflamação/genética , Exposição Materna , NF-kappa B/genética , Efeitos Tardios da Exposição Pré-Natal/genética , Transdução de Sinais , Adulto , Animais , Sítios de Ligação , Feminino , Perfilação da Expressão Gênica , Redes Reguladoras de Genes , Marcadores Genéticos , Genoma Humano/genética , Humanos , Recém-Nascido , Camundongos , Gravidez , Especificidade da Espécie , Tailândia , Fatores de Transcrição/metabolismo , Transcrição GênicaRESUMO
A theoretical analysis was developed to predict molecular hybridization rates for microarrays where samples flow through microfluidic channels and for conventional microarrays where samples remain stationary during hybridization. The theory was validated by using a multiplexed microfluidic microarray where eight samples were hybridized simultaneously against eight probes using 60-mer DNA strands. Mass transfer coefficients ranged over three orders of magnitude where either kinetic reaction rates or molecular diffusion rates controlled overall hybridization rates. Probes were printed using microfluidic channels and also conventional spotting techniques. Consistent with the theoretical model, the microfluidic microarray demonstrated the ability to print DNA probes in less than 1 min and to detect 10-pM target concentrations with hybridization times in less than 5 min.
