RESUMEN
El trasplante renal de órganos provenientes de donantes adultos implantados en una cavidad anatómica estrecha en pacientes pediátricos de bajo peso, ofrece importantes desafíos médicos y quirúrgicos a ser considerados. En esta publicación reportamos el primer caso en el Paraguay de un riñón con dos arterias renales injertado a la aorta y vena cava inferior, dentro de la cavidad abdominal de un paciente pediátrico de 12 kilogramos de peso, evaluando las dificultades médicas, anatómicas y quirúrgicas enfrentadas, así como las opciones de tratamiento instituidas para llevar a cabo este procedimiento de manera exitosa
Kidney transplantation of organs from adult donors implanted into a narrow anatomical cavity in underweight pediatric patients offers significant medical and surgical challenges to be considered. In this publication we report the first case in Paraguay of a kidney with two renal arteries, grafted to the aorta and inferior vena cava within the abdominal cavity, on a 12 kilogram pediatric patient, evaluating the medical, anatomical and surgical conditions faced, as well as the treatment options instituted to successfully carry out this procedure
Asunto(s)
Trasplante de Riñón , Riñón , ArteriasRESUMEN
Nucleic acids can fold into G-quadruplex (G4) structures that can fine-tune biological processes. Proteins are required to recognize G4 structures and coordinate their function. Here we identify Zuo1 as a novel G4-binding protein in vitro and in vivo. In vivo in the absence of Zuo1 fewer G4 structures form, cell growth slows and cells become UV sensitive. Subsequent experiments reveal that these cellular changes are due to reduced levels of G4 structures. Zuo1 function at G4 structures results in the recruitment of nucleotide excision repair (NER) factors, which has a positive effect on genome stability. Cells lacking functional NER, as well as Zuo1, accumulate G4 structures, which become accessible to translesion synthesis. Our results suggest a model in which Zuo1 supports NER function and regulates the choice of the DNA repair pathway nearby G4 structures.
Asunto(s)
Reparación del ADN/fisiología , G-Cuádruplex , Chaperonas Moleculares/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Sitios de Unión/genética , Daño del ADN , Reparación del ADN/genética , ADN de Hongos/química , ADN de Hongos/genética , ADN de Hongos/metabolismo , Eliminación de Gen , Aptitud Genética , Genoma Fúngico , Inestabilidad Genómica , Modelos Biológicos , Chaperonas Moleculares/genética , Nucleotidiltransferasas/genética , Nucleotidiltransferasas/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genéticaRESUMEN
G-quadruplex (G4) structures are highly stable four-stranded DNA and RNA secondary structures held together by non-canonical guanine base pairs. G4 sequence motifs are enriched at specific sites in eukaryotic genomes, suggesting regulatory functions of G4 structures during different biological processes. Considering the high thermodynamic stability of G4 structures, various proteins are necessary for G4 structure formation and unwinding. In a yeast one-hybrid screen, we identified Slx9 as a novel G4-binding protein. We confirmed that Slx9 binds to G4 DNA structures in vitro. Despite these findings, Slx9 binds only insignificantly to G-rich/G4 regions in Saccharomyces cerevisiae as demonstrated by genome-wide ChIP-seq analysis. However, Slx9 binding to G4s is significantly increased in the absence of Sgs1, a RecQ helicase that regulates G4 structures. Different genetic and molecular analyses allowed us to propose a model in which Slx9 recognizes and protects stabilized G4 structures in vivo.