7 research outputs found

    the melas mutation m 3243a g promotes reactivation of fetal cardiac genes and an epithelial mesenchymal transition like program via dysregulation of mirnas

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    Abstract The pathomechanisms underlying oxidative phosphorylation (OXPHOS) diseases are not well-understood, but they involve maladaptive changes in mitochondria-nucleus communication. Many studies on the mitochondria-nucleus cross-talk triggered by mitochondrial dysfunction have focused on the role played by regulatory proteins, while the participation of miRNAs remains poorly explored. MELAS (mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes) is mostly caused by mutation m.3243A>G in mitochondrial tRNALeu(UUR) gene. Adverse cardiac and neurological events are the commonest causes of early death in m.3243A>G patients. Notably, the incidence of major clinical features associated with this mutation has been correlated to the level of m.3243A>G mutant mitochondrial DNA (heteroplasmy) in skeletal muscle. In this work, we used a transmitochondrial cybrid model of MELAS (100% m.3243A>G mutant mitochondrial DNA) to investigate the participation of miRNAs in the mitochondria-nucleus cross-talk associated with OXPHOS dysfunction. High-throughput analysis of small-RNA-Seq data indicated that expression of 246 miRNAs was significantly altered in MELAS cybrids. Validation of selected miRNAs, including miR-4775 and miR-218-5p, in patient muscle samples revealed miRNAs whose expression declined with high levels of mutant heteroplasmy. We show that miR-218-5p and miR-4775 are direct regulators of fetal cardiac genes such as NODAL, RHOA, ISL1 and RXRB, which are up-regulated in MELAS cybrids and in patient muscle samples with heteroplasmy above 60%. Our data clearly indicate that TGF-β superfamily signaling and an epithelial-mesenchymal transition-like program are activated in MELAS cybrids, and suggest that down-regulation of miRNAs regulating fetal cardiac genes is a risk marker of heart failure in patients with OXPHOS diseases

    Intratumoral immunosuppression profiles in 11q-deleted neuroblastomas provide new potential therapeutic targets

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    High‐risk neuroblastoma (NB) patients with 11q deletion frequently undergo late but consecutive relapse cycles with fatal outcome. To date, no actionable targets to improve current multi‐modal treatment have been identified. We analyzed immune microenvironment and genetic profiles of high‐risk NB correlating with 11q immune status. We show in two independent cohorts that 11q‐deleted NB exhibit various immune‐inhibitory mechanisms, including increased CD4+ resting T cells and M2 macrophages, higher expression of programmed death‐ligand 1, interleukin‐10, transforming growth factor‐beta‐1 and indoleamine 2,3‐dioxygenase 1 (P<0.05), and also higher chromosomal breakages (P≤0.02) and hemizygosity of immunosuppressive miRNAs than MYCN‐amplified and other 11q‐non‐deleted high‐risk NB. We also analyzed benefits of maintenance treatment in 83 high‐risk stage M NB patients focusing on 11q status, either with standard anti‐GD2 immunotherapy (n=50) or previous retinoic acid‐based therapy alone (n=33). Immunotherapy associated with higher EFS (50 vs. 30, P=0.028) and OS (72 vs. 52, P=0.047) at 3 years in the overall population. Despite benefits from standard anti‐GD2 immunotherapy in high‐risk NB patients, those with 11q deletion still face poor outcome. This NB subgroup displays intratumoral immune suppression profiles, revealing a potential therapeutic strategy with combination immunotherapy to circumvent this immune checkpoint blockade

    Unraveling a novel transcription factor code determining the human arterial-specific endothelial cell signature

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    Endothelial cells (ECs) lining arteries and veins have distinct molecular/functional signatures. The underlying regulatory mechanisms are incompletely understood. Here, we established a specific fingerprint of freshly isolated arterial and venous ECs from human umbilical cord comprising 64 arterial and 12 venous genes, representing distinct functions/pathways. Among the arterial genes were 8 transcription factors (TFs), including Notch target HEY2, the current "gold standard" determinant for arterial EC (aEC) specification. Culture abrogated differential gene expression in part due to gradual loss of canonical Notch activity and HEY2 expression. Notably, restoring HEY2 expression or Delta-like4-induced Notch signaling in cultured ECs only partially reinstated the aEC gene signature, whereas combined overexpression of the 8 TFs restored this fingerprint more robustly. Whereas some TFs stimulated few genes, others boosted a large proportion of arterial genes. Although there was some overlap and cross-regulation, the TFs largely complemented each other in regulating the aEC gene profile. Finally, overexpression of the 8 TFs in human umbilical vein ECs conveyed an arterial-like behavior upon their implantation in a Matrigel plug in vivo. Thus, our study shows that Notch signaling determines only part of the aEC signature and identifies additional novel and complementary transcriptional players in the complex regulation of human arteriovenous EC identity.status: publishe

    Las nuevas tecnologías en Educación Infantil, Primaria y EGB

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    Memoria del proyecto de utilización de las nuevas tecnologías en el centro como recurso pedagógico y elemento de refuerzo a los conocimientos adquiridos en el aula. La experiencia consiste en el montaje de un aula de informática para todos los alumnos del centro, que se organiza en sesiones semanales para los niveles superiores y quincenales para los más bajos. En ella los alumnos trabajan en red a través de fichas de trabajo sobre las distintas áreas curriculares que se resuelven con los programas informáticos instalados. La evaluación señala que la aparición de un virus informático al instalar la red y las obras realizadas en la instalación eléctrica del aula han impedido prácticamente el desarrollo de la experiencia. No hay proyecto..Madrid (Comunidad Autónoma). Consejería de Educación y CulturaMadridMadrid (Comunidad Autónoma). Subdirección General de Formación del Profesorado. CRIF Las Acacias; General Ricardos 179 - 28025 Madrid; Tel. + 34915250893ES

    Confirmation of the topology of the Wendelstein 7-X magnetic field to better than 1:100,000

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    Fusion energy research has in the past 40 years focused primarily on the tokamak concept, but recent advances in plasma theory and computational power have led to renewed interest in stellarators. The largest and most sophisticated stellarator in the world, Wendelstein 7-X (W7-X), has just started operation, with the aim to show that the earlier weaknesses of this concept have been addressed successfully, and that the intrinsic advantages of the concept persist, also at plasma parameters approaching those of a future fusion power plant. Here we show the first physics results, obtained before plasma operation: that the carefully tailored topology of nested magnetic surfaces needed for good confinement is realized, and that the measured deviations are smaller than one part in 100,000. This is a significant step forward in stellarator research, since it shows that the complicated and delicate magnetic topology can be created and verified with the required accuracy
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