Infecciones y alteraciones epigenéticas en cáncer

ResumenLa participación de mecanismos epigenéticos, junto con infecciones en etapas tempranas de la vida, moldean lesiones premalignas del cáncer, en particular el cáncer gástrico, uno de los tumores más frecuentes en Chile, Latinoamérica y el mundo. El principal objetivo de este artículo, como parte de la serie de revisiones en torno a mecanismos epigenéticos en el desarrollo de enfermedades crónicas, es actualizar el rol de alteraciones epigenéticas (i.e. metilación del ADN) en el contexto de la infección crónica por H. pylori en las etapas precursoras del cáncer gástrico. Las investigaciones desarrolladas en esta área permiten delinear desafíos e interrogantes, en los cuales la pediatría tiene un papel preponderante en el desarrollo de estrategias de prevención y detección temprana de esta enfermedad.AbstractThe role of epigenetics and infectious diseases at early stages of life influence pre-malignant lesions of cancer, in particular, gastric cancer, one of the most frequent tumours in Chile, Latin America, and worldwide. This article examines the role of H.pylori and epigenetic alterations (i.e. DNA methylation) at early stages of gastric cancer and proposes, from the paediatric point of view, strategies for prevention and early detection

The Alhambra: Transformation and Change through Architectural Ceramics

In the following paper, we look at the Alhambra from a perspective of architectural ceramics, an essential element in the understanding of the monument. From the Nasrid era onward, glazed ceramic tile mosaics were used to adorn the walls, a style that extended into the Christian conquest, when the palace complex was used as a royal residence. Since then, restoration work has continued to be carried out on the alicatados that cover the Alhambra’s walls, especially during an intense period in the 19th century, when it was the subject of much interest from Romantic travellers to Granada. A detailed, documented analysis of this work shows the complexity of the palace and fortress complex, helping us to better understand a part of its history. In the following pages, we specifically focus on one room in the Alhambra, the so-called Cuarto Dorado (Golden Room), outlining the preliminary findings of a research project that we are undertaking in association with the University of Granada and the Patronato de la Alhambra y el Generalife (Council of the Alhambra and the Generalife).This research was funded by Universidad de Granada and the Patronato de la Alhambra y Generalife, grant number “The Alhambra’s Architectural Ceramics, addenda 4/2016”

The secreted autotransporter toxin (Sat) does not act as a virulence factor in the probiotic Escherichia coli strain Nissle 1917

BACKGROUND: Escherichia coli Nissle 1917 (EcN) is a probiotic used in the treatment of intestinal diseases. Although it is considered safe, EcN is closely related to the uropathogenic E. coli strain CFT073 and contains many of its predicted virulence elements. Thus, it is relevant to assess whether virulence-associated genes are functional in EcN. One of these genes encodes the secreted autotransporter toxin (Sat), a member of the serine protease autotransporters of Enterobacteriaceae (SPATEs) that are secreted following the type V autotransporter pathway. Sat is highly prevalent in certain E. coli pathogenic groups responsible for urinary and intestinal infections. In these pathogens Sat promotes cytotoxic effects in several lines of undifferentiated epithelial cells, but not in differentiated Caco-2 cells. RESULTS: Here we provide evidence that sat is expressed by EcN during the colonization of mouse intestine. The EcN protein is secreted as an active serine protease, with its 107 kDa-passenger domain released into the medium as a soluble protein. Expression of recombinant EcN Sat protein in strain HB101 increases paracellular permeability to mannitol in polarized Caco-2 monolayers. This effect, also reported for the Sat protein of diffusely adherent E. coli, is not observed when this protein is expressed in the EcN background. In addition, we show that EcN supernatants confer protection against Sat-mediated effects on paracellular permeability, thus indicating that other secreted EcN factors are able to prevent barrier disruption caused by pathogen-related factors. Sat is not required for intestinal colonization, but the EcNsat::cat mutant outcompetes wild-type EcN in the streptomycin-treated mouse model. Analysis of the presence of sat in 29 strains of the ECOR collection isolated from stools of healthy humans shows 34.8 % positives, with high prevalence of strains of the phylogenetic groups D and B2, related with extra-intestinal infections. CONCLUSIONS: Sat does not act as a virulence factor in EcN. The role of Sat in intestinal pathogenesis relies on other genetic determinants responsible for the bacterial pathotype

De puertas para adentro: Patrimonio y género en la Universidad de Granada

La serie editorial de Cuadernos Técnicos del Patrimonio surge debido a la necesidad de dotar al Vicerrectorado de Extensión Universitaria de publicaciones que aborden aspectos patrimoniales en relación con cuestiones de carácter transversal y que sirvan de vehículo de difusión y diálogo de las distintas colecciones que conforman el rico acervo universitario. El objetivo es convertir estos Cuadernos en un espacio de reflexión y debate sobre temas relacionados con la conservación, la restauración, la gestión, la difusión y la puesta en valor de los bienes muebles e inmuebles de la Universidad de Granada en toda su amplitud. No se plantean con un enfoque exclusivamente local pues su intención es abrirse a distintas problemáticas patrimoniales y convertirse en un instrumento que integre estudios de carácter nacional e internacional. Asimismo, entendemos que al Patrimonio hay que afrontarlo desde una perspectiva histórica pero también actual y en diálogo con la compleja realidad social

Outer membrane vesicles from the probiotic Escherichia coli Nissle 1917 and the commensal ECOR12 enter intestinal epithelial cells via clathrin-dependent endocytosis and elicit differential effects on DNA damage.

Interactions between intestinal microbiota and the human host are complex. The gut mucosal surface is covered by a mucin layer that prevents bacteria from accessing the epithelial cells. Thus, the crosstalk between microbiota and the host mainly rely on secreted factors that can go through the mucus layer and reach the epithelium. In this context, vesicles released by commensal strains are seen as key players in signaling processes in the intestinal mucosa. Studies with Gram-negative pathogens showed that outer membrane vesicles (OMVs) are internalized into the host cell by endocytosis, but the entry mechanism for microbiota-derived vesicles is unknown. Escherichia coli strains are found as part of normal human gut microbiota. In this work, we elucidate the pathway that mediate internalization of OMVs from the probiotic E.coli Nissle 1917 (EcN) and the commensal ECOR12 strains in several human intestinal epithelial cell lines. Time course measurement of fluorescence and microscopy analysis performed with rhodamine B-R18-labeled OMVs in the presence of endocytosis inhibitors showed that OMVs from these strains enter epithelial cells via clathrin-mediated endocytosis. Vesicles use the same endocytosis pathway in polarized epithelial monolayers. Internalized OMVs are sorted to lysosomal compartments as shown by their colocalization with clathrin and specific markers of endosomes and lysosomes. OMVs from both strains did not affect cell viability, but reduce proliferation of HT-29 cells. Labeling of 8-oxo-dG adducts in DNA revealed that neither OMVs from EcN nor from ECOR12 promoted oxidative DNA damage. In contrast, flow cytometry analysis of phosphorylated γH2AX evidenced that OMVs from the probiotic EcN significantly produced more double strand breaks in DNA than ECOR12 OMVs. The EcN genotoxic effects have been attributed to the synthesis of colibactin. However, it is not known how colibactin is exported and delivered into host cells. Whether colibactin is secreted via OMVs is an open question that needs further study

Optimization of injection parameters to obtain selected properties on foamed PP with hollow glass microspheres and thermally expandable microspheres using Taguchi method

Se utilizó un sistema de espumación compuesto por microesferas de vidrio huecas (HGM) y microesferas térmicamente expandibles (EM) para lograr un equilibrio entre las propiedades seleccionadas de polipropileno (PP) espumado mediante moldeo por inyección, combinando las mayores propiedades de flexión y menor densidad requeridas en las piezas interiores de los automóviles. El L16 de Taguchi (44.23) se empleó para el plan experimental y la relación señal/ruido (S/N) para la optimización del sistema planteado. Los dos parámetros importantes de moldeo por inyección que afectan a las propiedades seleccionadas fueron la temperatura de la masa fundida y del molde. El efecto más importante efecto sobre el módulo de flexión fue la cantidad de HGM, y para la densidad la cantidad de EM.Ministerio de Economía, Industria y Competitividad (project MAT2017-85101-C2-1-R

Un modelo de aprendizaje colaborativo para la Edad Moderna: el recurso a las TICS y su aplicación a un entorno de docencia virtual II

Depto. de Historia Moderna y ContemporáneaFac. de Geografía e HistoriaFALSEsubmitte