82 research outputs found
EL PROCESO DE MANEJO DEL AGUA EN LOS SUBSISTEMAS SOCIO-CULTURAL Y ECONÓMICO EN LA MICRO CUENCA EL PERICÓN, TECOANAPA, GUERRERO
El problema de suministro de agua en las viviendas es común en el ámbito rural de México y creciente en el país, pero el de su contaminación por usarla es general y poco atendido con eficiencia, por ello en esta investigación inicial se planteó el objetivo de analizar la microcuenca “El Pericón”, desde la perspectiva de su dimensión socio-cultural y económica, para su posterior integración con las dimensiones: biofísica, tecnológica y político-administrativa, como medio para el estudio y la gestión integral de la microcuenca en municipio de Tecoanapa, Guerrero, lo que implica un importante esfuerzo de integración interdisciplinaria para el equipo participante. El marco teórico se centra en las relaciones naturaleza-sociedad y en el proceso de manejo del agua, como una modalidad de dichas relaciones, en el ámbito de este recurso vital. El procedimiento seguido es el análisis de dos dimensiones para identificar puntos relevantes de la problemática y posteriormente conjuntarlos con las tres dimensiones restantes, para su modelación con fines a comprender las variables trascendentes y modificables de la problemática para su atención. Dentro de los resultados destaca la baja percepción en cuanto a las formas de actuación de la población y los productores para contaminar el agua y su posible reutilización, así como para reducir el desperdicio, sobre todo en fugas. También es relevante la alta marginación que sintetiza una serie de indicadores de la comunidad, que son relativamente bajos en los contextos estatal y nacional. Con ello una recomendación preliminar es la formación de conciencia ambiental en la población en general y en los productores agrícolas, en términos específicos sobre el papel que juegan en esta problemática
NSMCE2 suppresses cancer and aging in mice independently of its SUMO ligase activity.
The SMC5/6 complex is the least understood of SMC complexes. In yeast, smc5/6 mutants phenocopy mutations in sgs1, the BLM ortholog that is deficient in Bloom's syndrome (BS). We here show that NSMCE2 (Mms21, in Saccharomyces cerevisiae), an essential SUMO ligase of the SMC5/6 complex, suppresses cancer and aging in mice. Surprisingly, a mutation that compromises NSMCE2-dependent SUMOylation does not have a detectable impact on murine lifespan. In contrast, NSMCE2 deletion in adult mice leads to pathologies resembling those found in patients of BS. Moreover, and whereas NSMCE2 deletion does not have a detectable impact on DNA replication, NSMCE2-deficient cells also present the cellular hallmarks of BS such as increased recombination rates and an accumulation of micronuclei. Despite the similarities, NSMCE2 and BLM foci do not colocalize and concomitant deletion of Blm and Nsmce2 in B lymphocytes further increases recombination rates and is synthetic lethal due to severe chromosome mis-segregation. Our work reveals that SUMO- and BLM-independent activities of NSMCE2 limit recombination and facilitate segregation; functions of the SMC5/6 complex that are necessary to prevent cancer and aging in mice.The authors want to thank Jordi Torres and Mark O'Driscoll for comments on the manuscript. Work in OF laboratory related to this project was supported by Fundacion Botin, by Banco Santander through its Santander Universities Global Division and by grants from MINECO (SAF2011-23753 and SAF2014-57791-REDC), Howard Hughes Medical Institute, and the European Research Council (ERC-617840). Work in JM laboratory was funded by a grant from MINECO (BFU2013-49153P).S
Testbeds for Transition Metal Dichalcogenide Photonics: Efficacy of Light Emission Enhancement in Monomer vs. Dimer Nanoscale Antennae
Monolayer transition metal dichalcogenides are uniquely-qualified materials
for photonics because they combine well defined tunable direct band gaps and
selfpassivated surfaces without dangling bonds. However, the atomic thickness
of these 2D materials results in low photo absorption limiting the achievable
photo luminescence intensity. Such emission can, in principle, be enhanced via
nanoscale antennae resulting in; a. an increased absorption cross-section
enhancing pump efficiency, b. an acceleration of the internal emission rate via
the Purcell factor mainly by reducing the antennas optical mode volume beyond
the diffraction limit, and c. improved impedance matching of the emitter dipole
to the freespace wavelength. Plasmonic dimer antennae show orders of magnitude
hot-spot field enhancements when an emitter is positioned exactly at the
midgap. However, a 2D material cannot be grown, or easily transferred, to
reside in mid-gap of the metallic dimer cavity. In addition, a spacer layer
between the cavity and the emissive material is required to avoid non-radiative
recombination channels. Using both computational and experimental methods, in
this work we show that the emission enhancement from a 2D emitter- monomer
antenna cavity system rivals that of dimers at much reduced lithographic
effort. We rationalize this finding by showing that the emission enhancement in
dimer antennae does not specifically originate from the gap of the dimer
cavity, but is an average effect originating from the effective cavity
crosssection taken below each optical cavity where the emitting 2D film is
located. In particular, we test an array of different dimer and monomer antenna
geometries and observe a representative 3x higher emission for both monomer and
dimer cavities as compared to intrinsic emission of Chemical Vapor Deposition
synthesized WS2 flakes.Comment: 31 pages, 5 figure
Avaliação do apoio social e da auto-estima por indivíduos coronariopatas, segundo o sexo
Diagnostic Accuracy of HPV16 Early Antigen Serology For HPV-Driven Oropharyngeal Cancer is Independent of Age and Sex
Funding information: This project was funded in part by NIH/NIDCR R01 DE025712 (Paul Brennan, Brenda Diergaarde and Neil Hayes). The Alcohol-Related Cancers and Genetic Susceptibility Study in Europe (ARCAGE) was funded by the European Commission’s fifth framework program (QLK1-2001-00182), the Italian Association for Cancer Research, Compagnia di San Paolo/FIRMS, Region Piemonte and Padova University (CPDA057222). We thank Dr. Wolfgang Ahrens, PhD (Universität Bremen, Germany) for his support in ARCAGE study. The Carolina Head and Neck Cancer Epidemiology (CHANCE) study was supported in part by the National Cancer Institute (R01-CA90731). The Head and Neck 5000 study was a component of independent research funded by the National Institute for Health Research (NIHR) under its Programme Grants for Applied Research scheme (RP-PG-0707-10034). The views expressed in this publication are those of the author(s) and not necessarily those of the NHS, the NIHR or the Department of Health. Core funding was also provided through awards from Above and Beyond, University Hospitals Bristol and Weston Research Capability Funding and the NIHR Senior Investigator award to Professor Andy Ness. Human papillomavirus (HPV) serology was supported by a Cancer Research UK Programme Grant, the Integrative Cancer Epidemiology Programme (grant number: C18281/A19169). The University of Pittsburgh head and neck cancer case-control study is supported by US National Institutes of Health grants P50CA097190 and P30CA047904. The MSH-PMH study was supported by Canadian Cancer Society Research Institute and Lusi Wong Programs at the Princess Margaret Hospital Foundation.Peer reviewedPublisher PD
Bcr/Abl Interferes with the Fanconi Anemia/BRCA Pathway: Implications in the Chromosomal Instability of Chronic Myeloid Leukemia Cells
Chronic myeloid leukemia (CML) is a malignant clonal disorder of the hematopoietic system caused by the expression of the BCR/ABL fusion oncogene. Although it is well known that CML cells are genetically unstable, the mechanisms accounting for this genomic instability are still poorly understood. Because the Fanconi anemia (FA) pathway is believed to control several mechanisms of DNA repair, we investigated whether this pathway was disrupted in CML cells. Our data show that CML cells have a defective capacity to generate FANCD2 nuclear foci, either in dividing cells or after DNA damage. Similarly, human cord blood CD34+ cells transduced with BCR/ABL retroviral vectors showed impaired FANCD2 foci formation, whereas FANCD2 monoubiquitination in these cells was unaffected. Soon after the transduction of CD34+ cells with BCR/ABL retroviral vectors a high proportion of cells with supernumerary centrosomes was observed. Similarly, BCR/ABL induced a high proportion of chromosomal abnormalities, while mediated a cell survival advantage after exposure to DNA cross-linking agents. Significantly, both the impaired formation of FANCD2 nuclear foci, and also the predisposition of BCR/ABL cells to develop centrosomal and chromosomal aberrations were reverted by the ectopic expression of BRCA1. Taken together, our data show for the first time a disruption of the FA/BRCA pathway in BCR/ABL cells, suggesting that this defective pathway should play an important role in the genomic instability of CML by the co-occurrence of centrosomal amplification and DNA repair deficiencies
Frequency of potential interactions between drugs in medical prescriptions in a city in southern Brazil
Understanding the axonal response to injury by in vivo imaging in the mouse spinal cord: A tale of two branches.
Understanding the basic properties of how axons respond to injury in the mammalian central nervous system (CNS) is of fundamental value for developing strategies to promote neural repair. Axons possess complex morphologies with stereotypical branching patterns. However, current knowledge of the axonal response to injury gives little consideration to axonal branches, nor do strategies to promote axon regeneration. This article reviews evidence from in vivo spinal cord imaging that axonal branches markedly impact the degenerative and regenerative responses to injury. At a major bifurcation point, depending on whether one or both axonal branches are injured, neurons may choose either a more self-preservative response or a more dynamic response. The stabilizing effect of the spared branch may underlie a well-known divergence in neuronal responses to injury, and illustrates an example where in vivo spinal cord imaging reveals insights that are difficult to elucidate with conventional histological methods
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