139 research outputs found

    Loss of glutathione redox homeostasis impairs proteostasis by inhibiting autophagy-dependent protein degradation

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    In the presence of aggregation-prone proteins, the cytosol and endoplasmic reticulum (ER) undergo a dramatic shift in their respective redox status, with the cytosol becoming more oxidized and the ER more reducing. However, whether and how changes in the cellular redox status may affect protein aggregation is unknown. Here, we show that C. elegans loss-of-function mutants for the glutathione reductase gsr-1 gene enhance the deleterious phenotypes of heterologous human, as well as endogenous worm aggregation-prone proteins. These effects are phenocopied by the GSH-depleting agent diethyl maleate. Additionally, gsr-1 mutants abolish the nuclear translocation of HLH-30/TFEB transcription factor, a key inducer of autophagy, and strongly impair the degradation of the autophagy substrate p62/SQST-1::GFP, revealing glutathione reductase may have a role in the clearance of protein aggregates by autophagy. Blocking autophagy in gsr-1 worms expressing aggregation-prone proteins results in strong synthetic developmental phenotypes and lethality, supporting the physiological importance of glutathione reductase in the regulation of misfolded protein clearance. Furthermore, impairing redox homeostasis in both yeast and mammalian cells induces toxicity phenotypes associated with protein aggregation. Together, our data reveal that glutathione redox homeostasis may be central to proteostasis maintenance through autophagy regulation.. The Spanish Ministry of Economy and Competitiveness supported EF-S and VG (BFU2016–78265-P), PA (BFU2016– 79313-P and MDM-2016–0687), and AM-V (BFU2015–64408-P). AM-V was also supported by the Instituto de Salud Carlos III (PI11/ 00072) and RPV-M (CPII16/00004, PI14/00949 and PI17/00011). All projects were cofinanced by the Fondo Social Europeo (FEDER). AM-V is a member of the GENIE and EU-ROS Cost Actions of the European Union and RPV-M is a Marie Curie Fellow (CIG322034, EU)

    β-Cyclodextrins as affordable antivirals to treat coronavirus infection

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    The SARS-CoV-2 pandemic made evident that there are only a few drugs against coronavirus. Here we aimed to identify a cost-effective antiviral with broad spectrum activity and high safety profile. Starting from a list of 116 drug candidates, we used molecular modelling tools to rank the 44 most promising inhibitors. Next, we tested their efficacy as antivirals against α and β coronaviruses, such as the HCoV-229E and SARS-CoV-2 variants. Four drugs, OSW-1, U18666A, hydroxypropyl-β-cyclodextrin (HβCD) and phytol, showed in vitro antiviral activity against HCoV-229E and SARS-CoV-2. The mechanism of action of these compounds was studied by transmission electron microscopy and by fusion assays measuring SARS-CoV-2 pseudoviral entry into target cells. Entry was inhibited by HβCD and U18666A, yet only HβCD inhibited SARS-CoV-2 replication in the pulmonary Calu-3 cells. Compared to the other cyclodextrins, β-cyclodextrins were the most potent inhibitors, which interfered with viral fusion via cholesterol depletion. β-cyclodextrins also prevented infection in a human nasal epithelium model ex vivo and had a prophylactic effect in the nasal epithelium of hamsters in vivo. All accumulated data point to β-cyclodextrins as promising broad-spectrum antivirals against different SARS-CoV-2 variants and distant alphacoronaviruses. Given the wide use of β-cyclodextrins for drug encapsulation and their high safety profile in humans, our results support their clinical testing as prophylactic antivirals

    β-Cyclodextrins as affordable antivirals to treat coronavirus infection

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    The SARS-CoV-2 pandemic made evident that there are only a few drugs against coronavirus. Here we aimed to identify a cost-effective antiviral with broad spectrum activity and high safety profile. Starting from a list of 116 drug candidates, we used molecular modelling tools to rank the 44 most promising inhibitors. Next, we tested their efficacy as antivirals against α and β coronaviruses, such as the HCoV-229E and SARS-CoV-2 variants. Four drugs, OSW-1, U18666A, hydroxypropyl-β-cyclodextrin (HβCD) and phytol, showed in vitro antiviral activity against HCoV-229E and SARS-CoV-2. The mechanism of action of these compounds was studied by transmission electron microscopy and by fusion assays measuring SARS-CoV-2 pseudoviral entry into target cells. Entry was inhibited by HβCD and U18666A, yet only HβCD inhibited SARS-CoV-2 replication in the pulmonary Calu-3 cells. Compared to the other cyclodextrins, β-cyclodextrins were the most potent inhibitors, which interfered with viral fusion via cholesterol depletion. β-cyclodextrins also prevented infection in a human nasal epithelium model ex vivo and had a prophylactic effect in the nasal epithelium of hamsters in vivo. All accumulated data point to β-cyclodextrins as promising broad-spectrum antivirals against different SARS-CoV-2 variants and distant alphacoronaviruses. Given the wide use of β-cyclodextrins for drug encapsulation and their high safety profile in humans, our results support their clinical testing as prophylactic antivirals.This work has been funded by grant RTI2018-094445-B100 (MCIU/AEI/FEDER, UE) from the Ministry of Science and Innovation of Spain (C.R.), by Palex Medical S.A., Sika S.A.U. and 7 more companies, and by Ms. Raquel Casaus Alvarez, Mr. Miguel Pardo Gil, Mr. Jacques Noguès and a total of 2916 citizens through the Precipita crowdfunding platform of Fecyt (Fundación Española para la Ciencia y la Tecnología). NI-U is supported by the Spanish Ministry of Science and Innovation (grant PID2020-117145RB-I00), EU HORIZON-HLTH-2021-CORONA-01 (grant 101046118) and by institutional funding of Grifols, Pharma Mar, HIPRA, Amassence and Palobiofarma. This work used the computational resources of the Centro de Supercomputación de Galicia (CESGA) supported by the Partnership for Advanced Computing in Europe (PRACE) COVID-19 Fast Track Call for Proposals – Allocation Decision – Proposal COVID19-85.info:eu-repo/semantics/publishedVersio

    Radon and material radiopurity assessment for the NEXT double beta decay experiment

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    The Neutrino Experiment with a Xenon TPC (NEXT), intended to investigate the neutrinoless double beta decay using a high-pressure xenon gas TPC filled with Xe enriched in 136Xe at the Canfranc Underground Laboratory in Spain, requires ultra-low background conditions demanding an exhaustive control of material radiopurity and environmental radon levels. An extensive material screening process is underway for several years based mainly on gamma-ray spectroscopy using ultra-low background germanium detectors in Canfranc but also on mass spectrometry techniques like GDMS and ICPMS. Components from shielding, pressure vessel, electroluminescence and high voltage elements and energy and tracking readout planes have been analyzed, helping in the final design of the experiment and in the construction of the background model. The latest measurements carried out will be presented and the implication on NEXT of their results will be discussed. The commissioning of the NEW detector, as a first step towards NEXT, has started in Canfranc; in-situ measurements of airborne radon levels were taken there to optimize the system for radon mitigation and will be shown too.Comment: Proceedings of the Low Radioactivity Techniques 2015 workshop (LRT2015), Seattle, March 201

    Protection of Spanish Ibex (Capra pyrenaica) against Bluetongue Virus Serotypes 1 and 8 in a Subclinical Experimental Infection

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    Many wild ruminants such as Spanish ibex (Capra pyrenaica) are susceptible to Bluetongue virus (BTV) infection, which causes disease mainly in domestic sheep and cattle. Outbreaks involving either BTV serotypes 1 (BTV-1) and 8 (BTV-8) are currently challenging Europe. Inclusion of wildlife vaccination among BTV control measures should be considered in certain species. In the present study, four out of fifteen seronegative Spanish ibexes were immunized with a single dose of inactivated vaccine against BTV-1, four against BTV-8 and seven ibexes were non vaccinated controls. Seven ibexes (four vaccinated and three controls) were inoculated with each BTV serotype. Antibody and IFN-gamma responses were evaluated until 28 days after inoculation (dpi). The vaccinated ibexes showed significant (P<0.05) neutralizing antibody levels after vaccination compared to non vaccinated ibexes. The non vaccinated ibexes remained seronegative until challenge and showed neutralizing antibodies from 7 dpi. BTV RNA was detected in the blood of non vaccinated ibexes from 2 to the end of the study (28 dpi) and in target tissue samples obtained at necropsy (8 and 28 dpi). BTV-1 was successfully isolated on cell culture from blood and target tissues of non vaccinated ibexes. Clinical signs were unapparent and no gross lesions were found at necropsy. Our results show for the first time that Spanish ibex is susceptible and asymptomatic to BTV infection and also that a single dose of vaccine prevents viraemia against BTV-1 and BTV-8 replication

    FUMEPOC: Early detection of chronic obstructive pulmonary disease in smokers

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    <p>Abstract</p> <p>Background</p> <p>Currently is not feasible using conventional spirometry as a screening method in Primary Care especially among smoking population to detect chronic obstructive pulmonary disease in early stages. Therefore, the FUMEPOC study protocol intends to analyze the validity and reliability of Vitalograph COPD-6 spirometer as simpler tool to aid screening and diagnosis of this disease in early stages in primary care surgery.</p> <p>Methods / Design</p> <p>Study design: An observational, descriptive study of diagnostic tests, undertaken in Primary Care and Pneumology Outpatient Care Centre at San Juan Hospital and Elda Hospital. All smokers attending the primary care surgery and consent to participate in the study will undergo a test with Vitalograph COPD-6 spirometer. Subsequently, a conventional spirometry will be performed in the hospital and the results will be compared with those of the Vitalograph COPD-6 test.</p> <p>Discussion</p> <p>It is difficult to use the spirometry as screening for early diagnose test in real conditions of primary care clinical practice. The use of a simpler tool, Vitalograph COPD-6 spirometer, can help in the early diagnose and therefore, it could improve the clinical management of the disease.</p

    Toxoplasma gondii infection in seagull chicks is related to the consumption of freshwater food resources

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    Understanding the spread of Toxoplasma gondii ( T . gondii ) in wild birds, particularly in those with opportunistic feeding behavior, is of interest for elucidating the epidemiological involvement of these birds in the maintenance and dissemination of the parasite. Overall, from 2009 to 2011, we collected sera from 525 seagull chicks (Yellow-legged gull ( Larus michahellis ) and Audouin ' s gull ( L . audouinii )) from 6 breeding colonies in Spain and tested them using the modified agglutination test (MAT) for the presence of antibodies against T . gondii . Chick age was estimated from bill length. Main food source of seagull chicks was evaluated using stable isotope analyses from growing scapular feathers. Overall T . gondii seroprevalence was 21.0% (IC 95% 17.5 - 24.4). A generalized linear mixed-effects model indicated that year (2009) and food source (freshwater) were risk factors associated to the individual risk of infection by T. gondii, while age (days) was close to significance. Freshwa- ter food origin was related to the highest seroprevalence levels, followed by marine origin, supporting freshwater and sewages as important routes of dispersion of T . gondii . Year dif- ferences could indicate fluctuating rates of exposure of seagull chicks to T . gondii . Age ran- ged from 4 to 30 days and seropositivity tended to increase with age (P = 0.07), supporting that seropositivity is related to T. gondii infection rather than to maternal transfer of antibod- ies, which in gulls is known to sharply decrease with chick age. This study is the first to report T . gondii antibodies in Yellow-legged and Audouin ' s gulls, thereby extending the range of intermediate hosts for this parasite and underscoring the complexity of its epidemiolog

    Plio-Pleistocene climatic change had a major impact on the assembly and disassembly processes of Iberian rodent communities

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    Comprehension of changes in community composition through multiple spatio-temporal scales is a prime challenge in ecology and palaeobiology. However, assembly, structuring and disassembly of biotic metacommunities in deep-time is insufficiently known. To address this, we used the extensively sampled Iberian Plio-Pleistocene fossil record of rodent faunas as our model system to explore how global climatic events may alter metacommunity structure. Through factor analysis, we found five sets of genera, called faunal components, which co-vary in proportional diversity over time. These faunal components had different spatio-temporal distributions throughout the Plio-Pleistocene, resulting in non-random changes in species assemblages, particularly in response to the development of the Pleistocene glaciations. Three successive metacommunities with distinctive taxonomic structures were identified as a consequence of the differential responses of their members to global climatic change: (1) Ruscinian subtropical faunas (5.3–3.4 Ma) dominated by a faunal component that can be considered as a Miocene legacy; (2) transition faunas during the Villafranchian–Biharian (3.4–0.8 Ma) with a mixture of different faunal components; and (3) final dominance of the temperate Toringian faunas (0.8–0.01 Ma) that would lead to the modern Iberian assemblage. The influence of the cooling global temperature drove the reorganisation of these rodent metacommunities. Selective extinction processes due to this large-scale environmental disturbance progressively eliminated the subtropical specialist species from the early Pliocene metacommunity. This disassembly process was accompanied by the organisation of a diversified metacommunity with an increased importance of biome generalist species, and finally followed by the assembly during the middle–late Pleistocene of a new set of species specialised in the novel environments developed as a consequence of the glaciations

    Results of the material screening program of the NEXT experiment

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    [EN] The Neutrino Experiment with a Xenon TPC (NEXT), intended to investigate neutrinoless double beta decay, requires extremely low background levels. An extensive material screening and selection process to assess the radioactivity of components is underway combining several techniques, including germanium &#947;-ray spectrometry performed at the Canfranc Underground Laboratory; recent results of this material screening program are presented here.Dafni, T.; Álvarez-Puerta, V.; Bandac, I.; Bettini, A.; Borges, FIGM.; Camargo, M.; Carcel, S.... (2016). Results of the material screening program of the NEXT experiment. Nuclear and Particle Physics Proceedings. 273-275:2666-2668. https://doi.org/10.1016/j.nuclphysbps.2015.10.024S26662668273-27
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