RESUMO
The intronic SNP rs7903146 in the T-cell factor 7-like 2 gene (TCF7L2) is the common genetic variant most highly associated with Type 2 diabetes known to date. The risk T-allele is located in an open chromatin region specific to human pancreatic islets of Langerhans, thereby accessible for binding of regulatory proteins. The risk T-allele locus exhibits stronger enhancer activity compared to the non-risk C-allele. The aim of this study was to identify transcriptional regulators that bind the open chromatin region in the rs7903146 locus and thereby potentially regulate TCF7L2 expression and activity. Using affinity chromatography followed by Edman sequencing, we identified one candidate regulatory protein, i.e. high-mobility group protein B1 (HMGB1). The binding of HMGB1 to the rs7903146 locus was confirmed in pancreatic islets from human deceased donors, in HCT116 and in HEK293 cell lines using: (i) protein purification on affinity columns followed by Western blot, (ii) chromatin immunoprecipitation followed by qPCR and (iii) electrophoretic mobility shift assay. The results also suggested that HMGB1 might have higher binding affinity to the C-allele of rs7903146 compared to the T-allele, which was supported in vitro using Dynamic Light Scattering, possibly in a tissue-specific manner. The functional consequence of HMGB1 depletion in HCT116 and INS1 cells was reduced insulin and TCF7L2 mRNA expression, TCF7L2 transcriptional activity and glucose stimulated insulin secretion. These findings suggest that the rs7903146 locus might exert its enhancer function by interacting with HMGB1 in an allele dependent manner.
Assuntos
Loci Gênicos , Proteína HMGB1/metabolismo , Ilhotas Pancreáticas/metabolismo , Polimorfismo de Nucleotídeo Único/genética , Proteína 2 Semelhante ao Fator 7 de Transcrição/genética , Animais , Simulação por Computador , DNA/metabolismo , Difusão Dinâmica da Luz , Células HCT116 , Células HEK293 , Humanos , Hidrodinâmica , Ligação Proteica , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Reprodutibilidade dos TestesRESUMO
Algunas veces es necesario el transporte aéreo internacional de recién nacidos críticamente enfermos con necesidades especiales que amerita su traslado a centros regionales en el extranjero. Describimos nuestra experiencia con el transporte de neonatos críticamente enfermos desde Guatemala a San Petersburgo, Florida, EE.UU. Este artículo revisa lo relacionado con el transporte aéreo de recién nacidos enfermos incluyendo personal, equipo médico, administración de transporte e implementación de políticas. Los traslados fueron analizados por el tipo de avión, equipo médico y personal a bordo, duración del transporte, condición clínica durante el vuelo y a la llegada, complicaciones durante el transporte y los resultados al egreso de la unidad de cuidados intensivos neonatales . Los resultados indican que el uso de un enfoque multidisciplinario y una planificación cuidados permite un transporte aéreo óptimo y seguro.
