181 research outputs found

    Acanthamoeba activates macrophages predominantly through toll-like receptor 4 and MyD88-dependent mechanisms to induce Interleukin IL-12 and IL-6

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    Acanthamoeba castellanii is a free-living ubiquitous amoeba, with a worldwide distribution, that can occasionally infect humans, causing particularly severe infections in immune compromised individuals. Dissecting the immunology of Acanthamoeba infections has been considered problematic due to the very low incidence of disease despite the high exposure rates. Whilst macrophages are acknowledged as playing a significant role in Acanthamoeba infections little is known about how this facultative parasite influences macrophage activity. Therefore, in this study we investigate the effects of Acanthamoeba on the activation of resting macrophages. Consequently, murine bone marrow derived macrophages were co-cultured with trophozoites of either the laboratory Neff strain, or a clinical isolate of A. castellanii. In vitro real-time imaging demonstrated that trophozoites of both strains often established evanescent contact with macrophages. Both Acanthamoeba strains induced a pro-inflammatory macrophage phenotype characterized by significant production of IL-12 and IL-6. However, macrophages co-cultured with the clinical isolate of Acanthamoeba produced significantly less IL-12 and IL-6 in comparison to the Neff strain. The utilization of macrophages derived from MyD88, TRIF, TLR2, TLR4, TLR2/4 deficient mice indicated that Acanthamoeba-induced pro-inflammatory cytokine production was through MyD88-dependent, TRIF independent, TLR4-induced events. This study shows for the first time the involvement of TLRs, expressed on macrophages in the recognition and response to Acanthamoeba trophozoites

    Acanthamoeba castellanii (genotype T4) stimulates the production of interleukin-10 as well as pro-inflammatory cytokines in THP-1 cells, human peripheral blood mononuclear cells and human monocyte-derived macrophages

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    Free-living amoebae of the genus Acanthamoeba can cause severe and chronic infections in humans, mainly localized in immune privileged sites, as the brain and the eye. Monocytes/macrophages are thought to be involved in Acanthamoeba infections, but little is known about how these facultative parasites influence their functions. The aim of this work was to investigate the effects of Acanthamoeba on human monocytes/macrophages, during the early phase of infection. Herein, THP-1 cells, primary human monocytes isolated from peripheral blood and human monocyte-derived macrophages were either co-incubated with trophozoites of a clinical isolate of Acanthamoeba (genotype T4) or stimulated with amoeba-derived cell free conditioned medium. Production of pro-inflammatory cytokines (TNF-α, IL-6, IL-12), anti-inflammatory cytokine (IL-10) and chemokine (IL-8) was evaluated at specific hours post-stimulation (ranging from 1.30 h to 23 h). We showed that both Acanthamoeba trophozoites and soluble amoebic products induce an early anti-inflammatory monocyte-macrophage phenotype, characterized by a significant production of IL-10; furthermore, challenge with either trophozoites or their soluble metabolites stimulate both pro-inflammatory cytokines and chemokine production, suggesting that this protozoan infection may result from the early induction of coexisting, opposed immune responses. Results reported in this paper confirm that the production of pro-inflammatory cytokines and chemokines by monocytes and macrophages can play a role in the development of the inflammatory response during Acanthamoeba infections. Furthermore, we demonstrate for the first time that Acanthamoeba stimulates IL-10 production in human innate immune cells, which might both promote the immune evasion of Acanthamoeba and limit the induced inflammatory response

    The acanthamoeba shikimate pathway has a unique molecular arrangement and is essential for aromatic amino acid biosynthesis

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    The shikimate pathway is the only known biosynthetic route for de novo synthesis of aromatic compounds. It is described as an ancient eukaryotic innovation that has been retained in a subset of eukaryotes, replaced in plants through the acquisition of the chloroplast, but lost in many including humans. Herein, we demonstrate that Acanthamoeba castellanii possesses the shikimate pathway by biochemical and a combination of bioinformatics and molecular biological methods. The growth of A. castellanii (Neff strain and a recently isolated clinical specimen, both T4 genotypes) is inhibited by glyphosate [N-(phosphonomethyl) glycine], an inhibitor of EPSP synthase and the addition of phenylalanine and tryptophan, which are dependent on the shikimate pathway, rescued A. castellanii from glyphosate indicating that glyphosate was specific in action. A. castellanii has a novel complement of shikimate pathway enzymes including unique gene fusions, two Type I and one Type II DAHP synthases (for which their likely sensitivities to feedback inhibition by phenylalanine, tyrosine and tryptophan has been modelled) and a canonical chorismate synthase. The shikimate pathway in A. castellanii therefore has a novel molecular arrangement, is required for amino acid biosynthesis and represents an attractive target for antimicrobials

    Realización, exhibición y reflexión teórica del proyecto. Las flores de la abuela

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    Este proyecto cinematográfico del cortometraje Las flores de la abuela tiene dos componentes: la carpeta de producción y los ensayos individuales por área. La carpeta de producción contiene todos los aspectos relacionados a la parte creativa técnica del proyecto audiovisual. El ensayo Dirección: relaciones interpersonales y desempeño creativo para el proyecto Las flores de la abuela, se centra en la importancia del ambiente laboral en la preproducción y la producción de un cortometraje. Por otra parte, la Dirección de Arte con su ensayo Uso de paletas de colores en el proyecto cinematográfico Las flores de la abuela optó por realizar un estudio teórico sobre la utilización de paletas de colores de escenarios sombríos. También la Dirección de fotografía con el ensayo Identidad de planos y suspenso para el proyecto Las flores de la abuela, se centra en la investigación de la identidad de planos en un género cinematográfico, específicamente el género de suspenso, obteniendo como resultado que los planos cinematográficos tienen sus propio lenguaje audiovisual para narrar una historia, en este caso el plano subjetivo es uno de los más distintivos para el género suspenso-terror, debido a la tensión Psicológica que el espectador siente al verlo, ya que, es el único momento en que este se siente parte de la películaThis film project for the short film "Las Flores de la Abuela" has two components: the production folder and the individual essays by area. The production folder contains all aspects related to the technical and creative part of the audiovisual project. On the one hand, the essay Direction: Interpersonal Relationships and Performance for the project "Las Flores de la Abuela" focuses on the importance of the work environment in the preproduction and production of a short film. On the other hand, Art Direction's essay " Use of color palettes " in the film project "Las Flores de la Abuela" conducted a theoretical study on the use of color palettes in gloomy scenarios. Furthermore, the Direction of Photography's essay "Identity of shots and suspense" for the project "Las Flores de la Abuela" focuses on the investigation of the identity of shots in a film genre. The film genre, in this case, is the suspense genre, obtaining as a result that the cinematographic shots have their audiovisual language to tell a story. In this case, the subjective shot/picture is one of the most distinctive for the suspense-terror genre due to the psychological tension that the viewer feels when watching it since it is the only moment in which he feels part of the filmLicenciado en CineCuenc

    Intelektualna ometenost u visokom obrazovanju - samoprocena potreba za obukom univerzitetskih nastavnika

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    Introduction. The inclusion of students with disabilities in higher education is a fundamental right recognised by the legal system since its recognition in the United Nations Convention on the Rights of Persons with Disabilities. However, the measures adopted by European countries to promote their incorporation are not always accompanied by parallel training actions that provide university professors with the necessary knowledge to incorporate people with intellectual disabilities into the classroom with the same guarantees and opportunities as people without intellectual disabilities. Objective. This paper aims to provide specific data on the self-perceived training needs of university teaching staff and thus lay the foundations for a specific training programme. Methods. A cross-sectional study was carried out by means of a survey designed to collect the teachers' perceptions of their own competences and the effectiveness of their knowledge, as well as the importance they attached to some aspects of intellectual disability. The survey was administered to teachers in Serbia, the Netherlands, Portugal, Italy and Spain, with a total sample of 1009 teachers. Results. The results obtained showed that the perception of self-perceived competence in educational skills is dependent on three main factors: previous specific training, teaching experience with people with intellectual disabilities and own personal experiences. Conclusion. The present study demonstrated the concern and need of the teaching staff to obtain specific training on people with intellectual disabilities in higher education.Uvod: Inkluzija studenata sa ometenošću u visokom obrazovanju je fundamentalno pravo koje prepoznaje pravni sistem od usvajanja Konvencije Ujedinjenih nacija o pravima osoba sa ometenošću. Međutim, mere koje su preduzele evropske zemlje u promovisanju tih prava nisu uvek praćene obukama koje bi univerzitetskim nastavnicima obezbedile neophodna znanja za uključivanje osoba sa intelektualnom ometenošću u nastavu sa istim garancijama i mogućnostima koje se nude osobama tipičnog razvoja. Cilj: Cilj ovog istraživanja je da utvrdi potrebe za obukom na osnovu vlastite percepcije univerzitetskog nastavnog osoblja i da na taj način postavi temelje specifčnog programa obuke. Metode: Sprovedeno je transferzalno istraživanje pomoću upitnika kojim su prikupljeni podaci o vlastitoj proceni nastavnika u pogledu kompetencija i efektivnosti njihovog znanja, kao i o značaju koji oni pridaju pojedinim aspektima intelektualne ometenosti. Ispitivanje je izvršeno na uzorku od 1009 nastavnika iz Srbije, Holandije, Portugalije, Italije i Španije. Rezultati: Dobijeni rezultati pokazuju da je samoprocena kompetencija u edukativnim veštinama zavisna od tri glavna činioca: specifčnog treninga u prošlosti, iskustva u podučavanju osoba sa intelektualnom ometenošću i ličnih iskustava, Zaključak: Dobijeni rezultati ukazuju na potrebu za specifčnom obukom nastavnog osoblja u oblasti rada sa osobama sa intelektualnom ometenošću u visokom obrazovanju

    Library Newsletter

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    Volume 9, Number 1 August/September 2004Newsletter sent out to the campus in August 2004 with information about library services and resource

    Project overview and update on WEAVE: the next generation wide-field spectroscopy facility for the William Herschel Telescope

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    We present an overview of and status report on the WEAVE next-generation spectroscopy facility for the William Herschel Telescope (WHT). WEAVE principally targets optical ground-based follow up of upcoming ground-based (LOFAR) and space-based (Gaia) surveys. WEAVE is a multi-object and multi-IFU facility utilizing a new 2-degree prime focus field of view at the WHT, with a buffered pick-and-place positioner system hosting 1000 multi-object (MOS) fibres, 20 integral field units, or a single large IFU for each observation. The fibres are fed to a single spectrograph, with a pair of 8k(spectral) x 6k (spatial) pixel cameras, located within the WHT GHRIL enclosure on the telescope Nasmyth platform, supporting observations at R~5000 over the full 370-1000nm wavelength range in a single exposure, or a high resolution mode with limited coverage in each arm at R~20000. The project is now in the final design and early procurement phase, with commissioning at the telescope expected in 2017.Comment: 11 pages, 11 Figures, Summary of a presentation to Astronomical Telescopes and Instrumentation 201

    Report on the STECF Expert Working Group 17-12 Fisheries Dependent Information: ‘New-FDI’

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    The STECF expert working group (EWG) on Fisheries Dependant Information (FDI) took place in JRC, Ispra from 23 to 27 October 2017 to review the data transmitted by Member States under a new data call (‘New-FDI’). The new data call specification was designed with three broad aims in mind i) Compatibility between the New-FDI data and the data held in the Fleet Economic database. ii) Ability to encompass all EU registered vessels including those from the Mediterranean, Black Sea and external waters fleets. iii) Ability to assess effects of management measures. The main purpose of the EWG was to judge if the call specification was appropriate to accomplish the above aims and to consider any difficulties encountered by member states in fulfilling the data call. Two terms of reference also allowed trial analyses to be conducted of a type relevant to the third broad aim. The EWG addressed all Terms of Reference during the meeting and drew conclusions on the modifications required for the New-FDI data call going forwards. Prior to the EWG it had been agreed by STECF Bureau that the report of the meeting would not be presented to STECF for approval as an STECF report but published separately (as a JRC technical report). This report therefore presents the data, methods observations and findings of an EWG of the STECF but the findings presented in this report do not necessarily constitute the opinion of the STECF or reflect the views of the European Commission and in no way anticipate the Commission’s future policy in this area.JRC.D.2-Water and Marine Resource

    STECF Fisheries Dependent Information – FDI (STECF-19-11)

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    Commission Decision of 25 February 2016 setting up a Scientific, Technical and Economic Committee for Fisheries, C(2016) 1084, OJ C 74, 26.2.2016, p. 4–10. The Commission may consult the group on any matter relating to marine and fisheries biology, fishing gear technology, fisheries economics, fisheries governance, ecosystem effects of fisheries, aquaculture or similar disciplines. The STECF reviewed the report of the EWG on Fisheries-dependent Information during its winter 2019 plenary meeting

    Energy Estimation of Cosmic Rays with the Engineering Radio Array of the Pierre Auger Observatory

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    The Auger Engineering Radio Array (AERA) is part of the Pierre Auger Observatory and is used to detect the radio emission of cosmic-ray air showers. These observations are compared to the data of the surface detector stations of the Observatory, which provide well-calibrated information on the cosmic-ray energies and arrival directions. The response of the radio stations in the 30 to 80 MHz regime has been thoroughly calibrated to enable the reconstruction of the incoming electric field. For the latter, the energy deposit per area is determined from the radio pulses at each observer position and is interpolated using a two-dimensional function that takes into account signal asymmetries due to interference between the geomagnetic and charge-excess emission components. The spatial integral over the signal distribution gives a direct measurement of the energy transferred from the primary cosmic ray into radio emission in the AERA frequency range. We measure 15.8 MeV of radiation energy for a 1 EeV air shower arriving perpendicularly to the geomagnetic field. This radiation energy -- corrected for geometrical effects -- is used as a cosmic-ray energy estimator. Performing an absolute energy calibration against the surface-detector information, we observe that this radio-energy estimator scales quadratically with the cosmic-ray energy as expected for coherent emission. We find an energy resolution of the radio reconstruction of 22% for the data set and 17% for a high-quality subset containing only events with at least five radio stations with signal.Comment: Replaced with published version. Added journal reference and DO
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