2,496 research outputs found

    A potential immune escape mechanism by melanoma cells through the activation of chemokine-induced T cell death

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    AbstractThe immune system attempts to prevent or limit tumor growth, yet efforts to induce responses to tumors yield minimal results, rendering tumors virtually invisible to the immune system [1]. Several mechanisms may account for this subversion, including the triggering of tolerance to tumor antigens [2, 3], TGF-α or IL-10 production, downregulation of MHC molecules, or upregulation of FasL expression [4, 5]. Melanoma cells may in some instances use FasL expression to protect themselves against tumor-infiltrating lymphocytes (TIL) [4, 5]. Here, we show another, chemokine-dependent mechanism by which melanoma tumor cells shield themselves from immune reactions. Melanoma-inducible CCL5 (RANTES) production by infiltrating CD8 cells activates an apoptotic pathway in TIL involving cytochrome c release into the cytosol and activation of caspase-9 and -3. This process, triggered by CCL5 binding to CCR5, is not mediated by TNFα, Fas, or caspase-8. The effect is not unique to CCL5, as other CCR5 ligands such as CCL3 (MIP-1α) and CCL4 (MIP-1β) also trigger TIL cell death, nor is it limited to melanoma cells, as it also operates in activated primary T lymphocytes. The model assigns a role to the CXC chemokine CXCL12 (SDF-1α) in this process, as this melanoma cell-produced chemokine upregulates CCL5 production by TIL, initiating TIL cell death

    Perspectivas sobre o processo de ensinoaprendizagem-avaliação numa universidade portuguesa e outra espanhola

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    This article is the result of an investigation in higher education to identify factors of convergence and divergence of pedagogical practices for the understanding of the students' learning evaluation process at the University of Évora (Portugal) and the University of Castilla-La Mancha (Spain). The research methodology was framed on an interpretative paradigm through a mixed approach whose participants were the students and teachers of the teacher education courses. Data were collected through interviews with teachers, a questionnaire to students, and the analysis of institutional documents. The results reveal a strong relationship between the two universities, but with some relevant differences in the assessment dimension. The results reveal a strong relationship between pedagogical practices, in both universities, but with some relevant differences in the evaluative dimensionEl artículo que se presenta es un estudio para identificar los factores de convergencia y de divergencia en la práctica pedagógica con el fin de comprender el proceso de evaluación de los aprendizajes en la Universidad de Évora (Portugal) y en la Universidad de Castilla-La Mancha (España). Se empleó una metodología mixta desde un paradigma interpretativo con la participación de estudiantes y docentes de los grados de Educación Primaria. Los datos fueron recogidos mediate entrevistas a los docentes, un cuestionario a los estudiantes y el análisis de documentos institucionales. Los resultados indican una fuerte relación entre las prácticas pedagógicas, en ambas universidades, detectándose algunas diferencias relevantes en la dimensión evaluativa

    Isolation and phenotyping of potential stem cells from the umbilical cord of the bottlenose dolphin(Tursiops truncatus)

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    We have successfully isolated cells with stem-like properties from bottlenose dolphin (Tursiops truncatus) umbilical cord. Our results show that this cetacean species has embryonic fetal and adult stem cells as do humans and other studied mammals. This accomplishment allows to eventually investigate whether dolphins, due to their unique adaptations to aquatic environments, have special stem cell lineages or distinctive mechanisms of cell programming. Further characterization of their potency to differentiate into multiple cell lineages would fulfill numerous applicative purposes. We characterized, developed and refined a new protocol for obtaining potential stem cells from umbilical cord tissues of the bottlenose dolphin. Tissue samples were taken from umbilical cords of successful deliveries immediately after placenta ejection and collection from the water. Umbilical cord samples (2-3 cm3) were excised and subjected to enzymatic digestion and mechanical dissociation. Viable cells from specimens resident in the Oceanografic Valencia were cultured and subsequently isolated and tested for pluripotent characteristics (cell morphology, phenotype and expression of surface markers). Cell viability was confirmed also after freezing/thawing. The established protocol is suitable for collection/isolation/culture of dolphin potential mesenchymal stem cells from dolphin umbilical cord, which can be deposited in cell banks for future research needs

    Sociodemographic changes and trends in the rates of new perinatal HIV diagnoses and transmission in Spain from 1997 to 2015

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    Background There are not enough nationwide studies on perinatal HIV transmission in connection with a combination of antiretroviral treatments in Spain. Our objectives were to study sociodemographic changes and trends in the rates of HIV diagnoses and perinatal transmission in Spain from 1997 to 2015. Methods A retrospective study using data from Spanish Paediatric HIV Network (CoRISpe) and Spanish Minimum Basic Data Set (MDBS) was performed. HIV- diagnosed children between 1997 and 2015 were selected. Sociodemographic, clinical and immunovirological data of HIV-infected children and their mothers were studied in four calendar periods (P1: 1997-2000; P2: 2001-2005; P3: 2006-2010; P4: 2011-2015). Rates of perinatal HIV diagnoses and transmission from 1997 to 2015 were calculated. Results A total of 532 HIV-infected children were included in this study. Of these children, 406 were Spanish (76.3%) and 126 immigrants (23.7%). A decrease in the number of HIV diagnoses, 203 (38.2%) children in the first (P1), 149 (28%) in the second (P2), 130 (24.4%) in the third (P3) and 50 (9.4%) in the fourth (P4) calendar periods was studied. The same decrease in the Spanish HIV-infected children (P1, 174 (46.6%), P2, 115 (30.8%), P3, 65 (17.4%) and P4, 19 (5.1%)) was monitored. However, an increase in the number of HIV diagnoses by sexual contact (P1: 0%; P2: 1.3%; P3: 4.6%; P4: 16%) was observed. The rates of new perinatal HIV diagnoses and perinatal transmission in Spanish children decreased from 0.167 to 0.005 per 100,000 inhabitants and 11.4% to 0.4% between 1997 and 2015, respectively. Conclusions A decline of perinatal HIV diagnoses and transmission was observed. However, an increase of teen-agers HIV diagnoses with sexual infection was studied. Public awareness campaigns directed to teen-agers are advisable to prevent HIV infection by sexual contact

    Revista de Vertebrados de la Estación Biológica de Doñaña

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    Comportamiento reproductor del camaleón común (Chamaeleo chamaeleon L.) en el sur de EspañaDistribución de los reptiles en la provincia de Granada (SE. Península Ibérica)Datos sobre la reproducción y el crecimientode Psammodromus hispanicus Fitzinger, 1826 en un medio adehesado de la España CentralVariación en la colocación y orientación del nido del Alzacola (Cercotrichas galactotes) en dos especies de árbolesOrganización de la comunidad de aves reproductora en las landas montanas del País Vasco AtlánticoEcología de una población ibérica de lobos (Canis Lupus)Etude biométrique des Crosidures (Soricidae, Insectivora) de la región de Massa (Souss, Maroe).Variación geográfica del género Eliomys en la Península IbéricaTendencias gregarias del Ciervo (Cervus elaphus) en Doñana.Data on the autumn diet of the red deer (Cervus elaphus L. 1758) in the Montes de Toledo (Central Spain)Nota sobre la coexistencia de Hyla arborea (L. 1758E Hyla meridionalis (Boettger 1874) rn rl Valle del TiétarCalendario reproductivo y tamaño de las puesta en el galápago leproso, Mauremys leprosa (Shweigger, 1812), en Doñana, HuelvaPelícola (Felicola) inaqualis Piager, 1880 (MALLOPHAGA:TRICHODECTIDAE) parásito deE Herpestes ichneumon L (CARNIVORA: HERPESTIDAE)Abundancia y amplitud de los desplazamientos de Apodemus sylvaticus en cuatro biotopos de Doñana que difieren en cobertura vegetalPeer reviewe

    Revista de Vertebrados de la Estación Biológica de Doñaña

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    Alimentación de la boga del Guadiana (Chondrostoma polylepis wi/lkommi, Stein. 1866) en la interfase río-embalse de Sierra Boyera (Córdoba. España)Predación del búho real (Bubo bubo) sobre la perdiz roja (Alectoris rufa): selección de edad y sexoAlimentación de la nutria (Lutra lufra L, 1758)en el Nordeste de la Península IbéricaDatos sobre la distribución espacialde micromamíferos en el Parque Nacionalde DoñanaGuía para el reconocimiento microscópico de los pelos de los mamíferos de la Patagonia.Sobre la distribución geográfica de Anaecypris hispanica (STEINDACHNER, 1866) (OSTEICHTHYES, CYPRINIDAE)Cronología del periodo reproductor de Rana temporaria L. en La Coruña (NW de España).Un nuevo caso de melanismo en Natrix natrix (LINNAEUS 1758) procedente de Fuente Dé (Santander)Nuevas citas de anfibios y reptiles para el SE de la Península Ibérica.Datos sobre la dieta invernal del Búho chico (Asia atus) en la provinvia de LeónLa Distribucióndel Mara (Dolichotis patagonum) según criterios ecológicos e históricosSolapamiento entre la dieta de la cabra montés (Capra pyrenaica) y la del muflón (Ovis musimon)Nota sobre dietas de carnívoros e índices de abundancia en una Reserva de caza del norte de España.Discriminación osteométrica en el géneroTalpa (LINNEO, 1758), en el norte IbéricoObservaciones sobre el comportamiento depredativo de algunos colúbridos Ibéricos en estado salvajePeer reviewe

    Measurement of the cross-section and charge asymmetry of WW bosons produced in proton-proton collisions at s=8\sqrt{s}=8 TeV with the ATLAS detector

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    This paper presents measurements of the W+μ+νW^+ \rightarrow \mu^+\nu and WμνW^- \rightarrow \mu^-\nu cross-sections and the associated charge asymmetry as a function of the absolute pseudorapidity of the decay muon. The data were collected in proton--proton collisions at a centre-of-mass energy of 8 TeV with the ATLAS experiment at the LHC and correspond to a total integrated luminosity of 20.2~\mbox{fb^{-1}}. The precision of the cross-section measurements varies between 0.8% to 1.5% as a function of the pseudorapidity, excluding the 1.9% uncertainty on the integrated luminosity. The charge asymmetry is measured with an uncertainty between 0.002 and 0.003. The results are compared with predictions based on next-to-next-to-leading-order calculations with various parton distribution functions and have the sensitivity to discriminate between them.Comment: 38 pages in total, author list starting page 22, 5 figures, 4 tables, submitted to EPJC. All figures including auxiliary figures are available at https://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/STDM-2017-13

    Search for chargino-neutralino production with mass splittings near the electroweak scale in three-lepton final states in √s=13 TeV pp collisions with the ATLAS detector

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    A search for supersymmetry through the pair production of electroweakinos with mass splittings near the electroweak scale and decaying via on-shell W and Z bosons is presented for a three-lepton final state. The analyzed proton-proton collision data taken at a center-of-mass energy of √s=13  TeV were collected between 2015 and 2018 by the ATLAS experiment at the Large Hadron Collider, corresponding to an integrated luminosity of 139  fb−1. A search, emulating the recursive jigsaw reconstruction technique with easily reproducible laboratory-frame variables, is performed. The two excesses observed in the 2015–2016 data recursive jigsaw analysis in the low-mass three-lepton phase space are reproduced. Results with the full data set are in agreement with the Standard Model expectations. They are interpreted to set exclusion limits at the 95% confidence level on simplified models of chargino-neutralino pair production for masses up to 345 GeV

    Height and timing of growth spurt during puberty in young people living with vertically acquired HIV in Europe and Thailand.

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    OBJECTIVE: The aim of this study was to describe growth during puberty in young people with vertically acquired HIV. DESIGN: Pooled data from 12 paediatric HIV cohorts in Europe and Thailand. METHODS: One thousand and ninety-four children initiating a nonnucleoside reverse transcriptase inhibitor or boosted protease inhibitor based regimen aged 1-10 years were included. Super Imposition by Translation And Rotation (SITAR) models described growth from age 8 years using three parameters (average height, timing and shape of the growth spurt), dependent on age and height-for-age z-score (HAZ) (WHO references) at antiretroviral therapy (ART) initiation. Multivariate regression explored characteristics associated with these three parameters. RESULTS: At ART initiation, median age and HAZ was 6.4 [interquartile range (IQR): 2.8, 9.0] years and -1.2 (IQR: -2.3 to -0.2), respectively. Median follow-up was 9.1 (IQR: 6.9, 11.4) years. In girls, older age and lower HAZ at ART initiation were independently associated with a growth spurt which occurred 0.41 (95% confidence interval 0.20-0.62) years later in children starting ART age 6 to 10 years compared with 1 to 2 years and 1.50 (1.21-1.78) years later in those starting with HAZ less than -3 compared with HAZ at least -1. Later growth spurts in girls resulted in continued height growth into later adolescence. In boys starting ART with HAZ less than -1, growth spurts were later in children starting ART in the oldest age group, but for HAZ at least -1, there was no association with age. Girls and boys who initiated ART with HAZ at least -1 maintained a similar height to the WHO reference mean. CONCLUSION: Stunting at ART initiation was associated with later growth spurts in girls. Children with HAZ at least -1 at ART initiation grew in height at the level expected in HIV negative children of a comparable age

    Search for squarks and gluinos in events with isolated leptons, jets and missing transverse momentum at s√=8 TeV with the ATLAS detector

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    The results of a search for supersymmetry in final states containing at least one isolated lepton (electron or muon), jets and large missing transverse momentum with the ATLAS detector at the Large Hadron Collider are reported. The search is based on proton-proton collision data at a centre-of-mass energy s√=8 TeV collected in 2012, corresponding to an integrated luminosity of 20 fb−1. No significant excess above the Standard Model expectation is observed. Limits are set on supersymmetric particle masses for various supersymmetric models. Depending on the model, the search excludes gluino masses up to 1.32 TeV and squark masses up to 840 GeV. Limits are also set on the parameters of a minimal universal extra dimension model, excluding a compactification radius of 1/R c = 950 GeV for a cut-off scale times radius (ΛR c) of approximately 30
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