RESUMO
Currently, information about airway assessment and tracheal intubation is communicated verbally or in writing. Google Glass can record this information in real time with minimal disruption to work flow, using standard operating room lighting.
Assuntos
Computadores de Mão , Intubação Intratraqueal , Gravação em Vídeo/instrumentação , Adulto , Humanos , Laringoscopia , Masculino , Adulto JovemRESUMO
In mammals, X-chromosome inactivation (XCI) equalizes X-linked gene expression between XY males and XX females and is controlled by a specialized region known as the X-inactivation center (Xic). The Xic harbors two chromatin interaction domains, one centered around the noncoding Xist gene and the other around the antisense Tsix counterpart. Previous work demonstrated the existence of a chromatin transitional zone between the two domains. Here, we investigate the region and discover a conserved element, RS14, that presents a strong binding site for Ctcf protein. RS14 possesses an insulatory function suggestive of a boundary element and is crucial for cell differentiation and growth. Knocking out RS14 results in compromised Xist induction and aberrant XCI in female cells. These data demonstrate that a junction element between Tsix and Xist contributes to the initiation of XCI.
Assuntos
Cromatina/genética , Elementos Isolantes/genética , RNA não Traduzido/genética , Proteínas Repressoras/genética , Inativação do Cromossomo X , Animais , Sequência de Bases , Sítios de Ligação , Fator de Ligação a CCCTC , Linhagem Celular , Cromatina/metabolismo , Imunoprecipitação da Cromatina , Ensaio de Desvio de Mobilidade Eletroforética , Feminino , Expressão Gênica , Hibridização in Situ Fluorescente , Masculino , Camundongos , Camundongos da Linhagem 129 , Dados de Sequência Molecular , Mutação , Ligação Proteica , RNA Longo não Codificante , RNA não Traduzido/metabolismo , Proteínas Repressoras/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Homologia de Sequência do Ácido NucleicoRESUMO
In mammals, X-inactivation silences one of two female X chromosomes. Silencing depends on the noncoding gene, Xist (inactive X-specific transcript), and is blocked by the antisense gene, Tsix. Deleting the choice/imprinting center in Tsix affects X-chromosome selection. Here, we identify the insulator and transcription factor, CTCF, as a candidate trans-acting factor for X-chromosome selection. The choice/imprinting center contains tandem CTCF binding sites that function in an enhancer-blocking assay. In vitro binding is reduced by CpG methylation and abolished by including non-CpG methylation. We postulate that Tsix and CTCF together establish a regulatable epigenetic switch for X-inactivation.
