75 research outputs found

    Evaluation of European Deposit Insurance Scheme Funding based on risk analysis

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    We carry out a quantitative analysis of the financing measures proposed for the European Deposit Insurance Scheme (EDIS) regarding the target level of the fund and the contribution scheme of member entities. We estimate the loss distribution of the EDIS considering different sources of systemic risk associated with the correlations between bank assets and we analyse the sensitivity of the results to bank portfolio risk. Our findings show how the interconnection between banks of different countries has an important influence on accumulated losses in the tail of the distribution. Likewise deterioration in the quality of bank portfolios produces a significant reduction in the fund’s loss-absorbing capacity, which calls into question its soundness in times of economic recession. Finally, the contribution scheme provides more equitable risk measures and may be an appropriate incentive to reduce moral hazard in the Banking Union

    Electro-responsive films containing voltage responsive gated mesoporous silica nanoparticles grafted onto PEDOT-based conducting polymer

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    [EN] The characteristics and electromechanical properties of conductive polymers together to their biocompatibility have boosted their application as a suitable tool in regenerative medicine and tissue engineering. However, conducting polymers as drug release materials are far from being ideal. A possibility to overcome this drawback is to combine conducting polymers with on-command delivery particles with inherent high-loading capacity. In this scenario, we report here the preparation of conduction polymers containing gated mesoporous silica nanoparticles (MSN) loaded with a cargo that is delivered on command by electro-chemical stimuli increasing the potential use of conducting polymers as controlled delivery systems. MSNs are loaded with Rhodamine B (Rh B), anchored to the conductive polymer poly(3,4-ethylenedioxythiophene) (PEDOT) doped with poly[(4-styrenesulfonic acid)-co-(maleic acid)], functionalized with a bipyridinium derivative and pores are capped with heparin (P3) by electrostatic interactions. P3 releases the entrapped cargo after the application of ¿640 mV voltage versus the saturated calomel electrode (SCE). Pore opening in the nanoparticles and dye delivery is ascribed to both (i) the reduction of the grafted bipyridinium derivative and (ii) the polarization of the conducting polymer electrode to negative potentials that induce detachment of positively charged heparin from the surface of the nanoparticles. Biocompatibility and cargo release studies were carried out in HeLa cells cultures.Alba Garcia-Fernandez, Beatriz Lozano-Torres contributed equally to this work. A. Garcia-Fernandez and B. Lozano-Torres are grateful to the "Ministerio de Economia y Competitividad" of the Spanish Government for her PhD fellowships. J. F. Blandez thanks the "Universitat Politecnica de Valencia" for his postdoctoral fellowship (PAID-10-17). The authors thank to the Spanish Government (Projects RTI2018-100910-B-C41 and RTI2018-101599-B-C22 (MCUI/AEI/FEDER, EU)) and the Generalitat Valencia (Project PROMETEO2018-024) for support.García-Fernández, A.; Lozano-Torres, B.; Blandez, JF.; Monreal-Trigo, J.; Soto Camino, J.; Collazos-Castro, JE.; Alcañiz Fillol, M.... (2020). Electro-responsive films containing voltage responsive gated mesoporous silica nanoparticles grafted onto PEDOT-based conducting polymer. Journal of Controlled Release. 323:421-430. https://doi.org/10.1016/j.jconrel.2020.04.048S421430323Aznar, E., Oroval, M., Pascual, L., Murguía, J. R., Martínez-Máñez, R., & Sancenón, F. (2016). Gated Materials for On-Command Release of Guest Molecules. Chemical Reviews, 116(2), 561-718. doi:10.1021/acs.chemrev.5b00456Mura, S., Nicolas, J., & Couvreur, P. (2013). Stimuli-responsive nanocarriers for drug delivery. Nature Materials, 12(11), 991-1003. doi:10.1038/nmat3776Llopis-Lorente, A., Lozano-Torres, B., Bernardos, A., Martínez-Máñez, R., & Sancenón, F. (2017). Mesoporous silica materials for controlled delivery based on enzymes. Journal of Materials Chemistry B, 5(17), 3069-3083. doi:10.1039/c7tb00348jTarn, D., Ashley, C. E., Xue, M., Carnes, E. C., Zink, J. I., & Brinker, C. J. (2013). Mesoporous Silica Nanoparticle Nanocarriers: Biofunctionality and Biocompatibility. Accounts of Chemical Research, 46(3), 792-801. doi:10.1021/ar3000986Mauriello Jimenez, C., Aggad, D., Croissant, J. G., Tresfield, K., Laurencin, D., Berthomieu, D., … Durand, J.-O. (2018). Porous Porphyrin-Based Organosilica Nanoparticles for NIR Two-Photon Photodynamic Therapy and Gene Delivery in Zebrafish. Advanced Functional Materials, 28(21), 1800235. doi:10.1002/adfm.201800235Alberti, S., Soler-Illia, G. J. A. A., & Azzaroni, O. (2015). Gated supramolecular chemistry in hybrid mesoporous silica nanoarchitectures: controlled delivery and molecular transport in response to chemical, physical and biological stimuli. Chemical Communications, 51(28), 6050-6075. doi:10.1039/c4cc10414eLlopis-Lorente, A., de Luis, B., García-Fernández, A., Jimenez-Falcao, S., Orzáez, M., Sancenón, F., … Martínez-Máñez, R. (2018). Hybrid Mesoporous Nanocarriers Act by Processing Logic Tasks: Toward the Design of Nanobots Capable of Reading Information from the Environment. ACS Applied Materials & Interfaces, 10(31), 26494-26500. doi:10.1021/acsami.8b05920Yang, P., Gai, S., & Lin, J. (2012). Functionalized mesoporous silica materials for controlled drug delivery. Chemical Society Reviews, 41(9), 3679. doi:10.1039/c2cs15308dSong, N., & Yang, Y.-W. (2015). Molecular and supramolecular switches on mesoporous silica nanoparticles. Chemical Society Reviews, 44(11), 3474-3504. doi:10.1039/c5cs00243eOroval, M., Díez, P., Aznar, E., Coll, C., Marcos, M. D., Sancenón, F., … Martínez-Máñez, R. (2016). Self-Regulated Glucose-Sensitive Neoglycoenzyme-Capped Mesoporous Silica Nanoparticles for Insulin Delivery. Chemistry - A European Journal, 23(6), 1353-1360. doi:10.1002/chem.201604104De la Torre, C., Domínguez-Berrocal, L., Murguía, J. R., Marcos, M. D., Martínez-Máñez, R., Bravo, J., & Sancenón, F. (2018). ϵ -Polylysine-Capped Mesoporous Silica Nanoparticles as Carrier of the C 9h Peptide to Induce Apoptosis in Cancer Cells. Chemistry - A European Journal, 24(8), 1890-1897. doi:10.1002/chem.201704161Llopis-Lorente, A., Díez, P., Sánchez, A., Marcos, M. D., Sancenón, F., Martínez-Ruiz, P., … Martínez-Máñez, R. (2017). Interactive models of communication at the nanoscale using nanoparticles that talk to one another. Nature Communications, 8(1). doi:10.1038/ncomms15511Pascual, L., Baroja, I., Aznar, E., Sancenón, F., Marcos, M. D., Murguía, J. R., … Martínez-Máñez, R. (2015). Oligonucleotide-capped mesoporous silica nanoparticles as DNA-responsive dye delivery systems for genomic DNA detection. Chemical Communications, 51(8), 1414-1416. doi:10.1039/c4cc08306gArgyo, C., Weiss, V., Bräuchle, C., & Bein, T. (2013). Multifunctional Mesoporous Silica Nanoparticles as a Universal Platform for Drug Delivery. Chemistry of Materials, 26(1), 435-451. doi:10.1021/cm402592tLi, Z., Barnes, J. C., Bosoy, A., Stoddart, J. F., & Zink, J. I. (2012). Mesoporous silica nanoparticles in biomedical applications. Chemical Society Reviews, 41(7), 2590. doi:10.1039/c1cs15246gKumar, P., Tambe, P., Paknikar, K. M., & Gajbhiye, V. (2018). Mesoporous silica nanoparticles as cutting-edge theranostics: Advancement from merely a carrier to tailor-made smart delivery platform. Journal of Controlled Release, 287, 35-57. doi:10.1016/j.jconrel.2018.08.024Lai, C.-Y., Trewyn, B. G., Jeftinija, D. M., Jeftinija, K., Xu, S., Jeftinija, S., & Lin, V. S.-Y. (2003). A Mesoporous Silica Nanosphere-Based Carrier System with Chemically Removable CdS Nanoparticle Caps for Stimuli-Responsive Controlled Release of Neurotransmitters and Drug Molecules. Journal of the American Chemical Society, 125(15), 4451-4459. doi:10.1021/ja028650lLiu, R., Zhao, X., Wu, T., & Feng, P. (2008). Tunable Redox-Responsive Hybrid Nanogated Ensembles. Journal of the American Chemical Society, 130(44), 14418-14419. doi:10.1021/ja8060886Qu, H., Yang, L., Yu, J., Dong, T., Rong, M., Zhang, J., … Liu, H. (2017). A redox responsive controlled release system using mesoporous silica nanoparticles capped with Au nanoparticles. RSC Advances, 7(57), 35704-35710. doi:10.1039/c7ra04444eGiménez, C., de la Torre, C., Gorbe, M., Aznar, E., Sancenón, F., Murguía, J. R., … Amorós, P. (2015). Gated Mesoporous Silica Nanoparticles for the Controlled Delivery of Drugs in Cancer Cells. Langmuir, 31(12), 3753-3762. doi:10.1021/acs.langmuir.5b00139Luo, Z., Hu, Y., Cai, K., Ding, X., Zhang, Q., Li, M., … Zhao, Y. (2014). Intracellular redox-activated anticancer drug delivery by functionalized hollow mesoporous silica nanoreservoirs with tumor specificity. Biomaterials, 35(27), 7951-7962. doi:10.1016/j.biomaterials.2014.05.058Du, X., Xiong, L., Dai, S., Kleitz, F., & Qiao, S. Z. (2014). Intracellular Microenvironment-Responsive Dendrimer-Like Mesoporous Nanohybrids for Traceable, Effective, and Safe Gene Delivery. Advanced Functional Materials, 24(48), 7627-7637. doi:10.1002/adfm.201402408Raza, A., Hayat, U., Rasheed, T., Bilal, M., & Iqbal, H. M. N. (2018). Redox-responsive nano-carriers as tumor-targeted drug delivery systems. European Journal of Medicinal Chemistry, 157, 705-715. doi:10.1016/j.ejmech.2018.08.034Xiao, Y., Wang, T., Cao, Y., Wang, X., Zhang, Y., Liu, Y., & Huo, Q. (2015). Enzyme and voltage stimuli-responsive controlled release system based on β-cyclodextrin-capped mesoporous silica nanoparticles. Dalton Transactions, 44(9), 4355-4361. doi:10.1039/c4dt03758hWang, T., Sun, G., Wang, M., Zhou, B., & Fu, J. (2015). Voltage/pH-Driven Mechanized Silica Nanoparticles for the Multimodal Controlled Release of Drugs. ACS Applied Materials & Interfaces, 7(38), 21295-21304. doi:10.1021/acsami.5b05619Jiao, X., Sun, R., Cheng, Y., Li, F., Du, X., Wen, Y., … Zhang, X. (2017). A Voltage-Responsive Free-Blockage Controlled-Release System Based on Hydrophobicity Switching. ChemPhysChem, 18(10), 1317-1323. doi:10.1002/cphc.201700117Khashab, N. M., Trabolsi, A., Lau, Y. A., Ambrogio, M. W., Friedman, D. C., Khatib, H. A., … Stoddart, J. F. (2009). Redox- and pH-Controlled Mechanized Nanoparticles. European Journal of Organic Chemistry, 2009(11), 1669-1673. doi:10.1002/ejoc.200801300Guimard, N. K., Gomez, N., & Schmidt, C. E. (2007). Conducting polymers in biomedical engineering. Progress in Polymer Science, 32(8-9), 876-921. doi:10.1016/j.progpolymsci.2007.05.012Wang, X., Zhi, L., & Müllen, K. (2007). Transparent, Conductive Graphene Electrodes for Dye-Sensitized Solar Cells. Nano Letters, 8(1), 323-327. doi:10.1021/nl072838rLeigh, S. J., Bradley, R. J., Purssell, C. P., Billson, D. R., & Hutchins, D. A. (2012). A Simple, Low-Cost Conductive Composite Material for 3D Printing of Electronic Sensors. PLoS ONE, 7(11), e49365. doi:10.1371/journal.pone.0049365Zhang, D., Ryu, K., Liu, X., Polikarpov, E., Ly, J., Tompson, M. E., & Zhou, C. (2006). Transparent, Conductive, and Flexible Carbon Nanotube Films and Their Application in Organic Light-Emitting Diodes. Nano Letters, 6(9), 1880-1886. doi:10.1021/nl0608543Kenry, & Liu, B. (2018). Recent Advances in Biodegradable Conducting Polymers and Their Biomedical Applications. Biomacromolecules, 19(6), 1783-1803. doi:10.1021/acs.biomac.8b00275Palza, H., Zapata, P., & Angulo-Pineda, C. (2019). Electroactive Smart Polymers for Biomedical Applications. Materials, 12(2), 277. doi:10.3390/ma12020277Naseri, M., Fotouhi, L., & Ehsani, A. (2018). Recent Progress in the Development of Conducting Polymer-Based Nanocomposites for Electrochemical Biosensors Applications: A Mini-Review. The Chemical Record, 18(6), 599-618. doi:10.1002/tcr.201700101Inal, S., Rivnay, J., Suiu, A.-O., Malliaras, G. G., & McCulloch, I. (2018). Conjugated Polymers in Bioelectronics. Accounts of Chemical Research, 51(6), 1368-1376. doi:10.1021/acs.accounts.7b00624Aqrawe, Z., Montgomery, J., Travas-Sejdic, J., & Svirskis, D. (2017). Conducting Polymers as Electrode Coatings for Neuronal Multi-electrode Arrays. 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(2016). Biofunctionalized PEDOT-coated microfibers for the treatment of spinal cord injury. Biomaterials, 89, 98-113. doi:10.1016/j.biomaterials.2016.02.037Guo, B., & Ma, P. X. (2018). Conducting Polymers for Tissue Engineering. Biomacromolecules, 19(6), 1764-1782. doi:10.1021/acs.biomac.8b00276Wadhwa, R., Lagenaur, C. F., & Cui, X. T. (2006). Electrochemically controlled release of dexamethasone from conducting polymer polypyrrole coated electrode. Journal of Controlled Release, 110(3), 531-541. doi:10.1016/j.jconrel.2005.10.027Shamaeli, E., & Alizadeh, N. (2014). Nanostructured biocompatible thermal/electrical stimuli-responsive biopolymer-doped polypyrrole for controlled release of chlorpromazine: Kinetics studies. International Journal of Pharmaceutics, 472(1-2), 327-338. doi:10.1016/j.ijpharm.2014.06.036Esrafilzadeh, D., Razal, J. M., Moulton, S. E., Stewart, E. M., & Wallace, G. G. (2013). Multifunctional conducting fibres with electrically controlled release of ciprofloxacin. 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    Petrographic and geochemical evidence for multiphase formation of carbonates in the Martian orthopyroxenite Allan Hills 84001

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    This research has been funded by the Spanish Ministry of Science and Innovation (projects: AYA2011‐26,522, AYA 2015‐67175‐P, CTQ2015‐62,635‐ERC, and CTQ2014‐60,119‐P to which J.M. Trigo‐Rodríguez and C.E. Moyano‐Cambero acknowledge financial support). The UK Science and Technology Facilities Council is also thanked for funding through grants ST/H002960/1, ST/K000942/1, and ST/L002167/1. ICN2 and ICMAB acknowledge support of the Spanish MINECO through the Severo Ochoa Centers of Excellence Program under Grants SEV‐2013‐0295 and SEV‐2015‐0496, respectively. We acknowledge B. Ballesteros and M. Rosado from the ICN2 Electron Microscopy Division, and A. Fernández from the ICTS (National Center of Electronic Microscopy) for the SEM, EDS, and microprobe measurements. We also thank the NASA Meteorite Working Group, and the Johnson Space Center for providing the ALH 84001,82 section. This study was done in the frame of a PhD on Physics at the Autonomous University of Barcelona (UAB) under the direction of J. M. Trigo‐Rodríguez.Peer reviewedPublisher PD

    The granite and glacial landscapes of the Peneda-Gerês National Park

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    Granite and glacial landforms are presented as the main geomorphological landscape features of the Peneda-Gerês National Park. The park was established in 1971 and it is the only national park and most important protected area in Portugal. The aesthetic attractiveness is supported mainly by the distinct granite landscape of the Gerês and Peneda Mountains, where the post-orogenic Variscan Gerês gran- ite facies occurs. The rugged relief is poorly covered by vegetation, differentiating it from the surrounding moun- tainous areas and the most distinctive landforms are bornhardts, locally named as “medas”. Typical glacial landforms, such as U-shaped valleys, cirques and moraines, express the sheltered character of a low-altitude glaciation, which is of great significance in the context of the Pleistocene glaciation in Southern Europe.This work is co-funded by the European Union through the European Regional Development Fund, based on COMPETE 2020 (Programa Operacional da Competitividade e Inter nacionalização), project ICT (UID/GEO/04683/2013) with reference POCI-01-0145- FEDER-007690 and Portuguese national funds pro vided by Fundação para a Ciência e Tecnologi

    Revealing the last 13,500 years of environmental history from the multiproxy record of a mountain lake (Lago Enol, northern Iberian Peninsula)

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    This is the author's accepted manuscript. The final publication is available at Springer via http://dx.doi.org/10.1007/s10933-009-9387-7.We present the Holocene sequence from Lago Enol (43°16′N, 4°59′W, 1,070 m a.s.l.), Cantabrian Mountains, northern Spain. A multiproxy analysis provided comprehensive information about regional humidity and temperature changes. The analysis included sedimentological descriptions, physical properties, organic carbon and carbonate content, mineralogy and geochemical composition together with biological proxies including diatom and ostracod assemblages. A detailed pollen study enabled reconstruction of variations in vegetation cover, which were interpreted in the context of climate changes and human impact. Four distinct stages were recognized for the last 13,500 years: (1) a cold and dry episode that includes the Younger Dryas event (13,500–11,600 cal. year BP); (2) a humid and warmer period characterizing the onset of the Holocene (11,600–8,700 cal. year BP); (3) a tendency toward a drier climate during the middle Holocene (8,700–4,650 cal. year BP); and (4) a return to humid conditions following landscape modification by human activity (pastoral activities, deforestation) in the late Holocene (4,650–2,200 cal. year BP). Superimposed on relatively stable landscape conditions (e.g. maintenance of well established forests), the typical environmental variability of the southern European region is observed at this site.The Spanish Inter-Ministry Commission of Science and Technology (CICYT), the Spanish National Parks agency, the European Commission, the Spanish Ministry of Science, and the European Social Fund

    Revealing the last 13,500 years of environmental history from the multiproxy record of a mountain lake (Lago Enol, northern Iberian Peninsula)

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    This is the author's accepted manuscript. The final publication is available at Springer via http://dx.doi.org/10.1007/s10933-009-9387-7.We present the Holocene sequence from Lago Enol (43°16′N, 4°59′W, 1,070 m a.s.l.), Cantabrian Mountains, northern Spain. A multiproxy analysis provided comprehensive information about regional humidity and temperature changes. The analysis included sedimentological descriptions, physical properties, organic carbon and carbonate content, mineralogy and geochemical composition together with biological proxies including diatom and ostracod assemblages. A detailed pollen study enabled reconstruction of variations in vegetation cover, which were interpreted in the context of climate changes and human impact. Four distinct stages were recognized for the last 13,500 years: (1) a cold and dry episode that includes the Younger Dryas event (13,500–11,600 cal. year BP); (2) a humid and warmer period characterizing the onset of the Holocene (11,600–8,700 cal. year BP); (3) a tendency toward a drier climate during the middle Holocene (8,700–4,650 cal. year BP); and (4) a return to humid conditions following landscape modification by human activity (pastoral activities, deforestation) in the late Holocene (4,650–2,200 cal. year BP). Superimposed on relatively stable landscape conditions (e.g. maintenance of well established forests), the typical environmental variability of the southern European region is observed at this site.The Spanish Inter-Ministry Commission of Science and Technology (CICYT), the Spanish National Parks agency, the European Commission, the Spanish Ministry of Science, and the European Social Fund

    Nanoindenting the Chelyabinsk meteorite to learn about impact deflection effects in asteroids

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    The Chelyabinsk meteorite is a highly shocked, low porosity, ordinary chondrite, probably similar to S- or Q-type asteroids. Therefore, nanoindentation experiments on this meteorite allow us to obtain key data to understand the physical properties of near-Earth asteroids (NEAs). Tests at different length scales provide information about the local mechanical properties of the minerals forming this meteorite: reduced Young's modulus, hardness, elastic recovery, and fracture toughness. Those tests are also useful to understand the potential to deflect threatening asteroids using a kinetic projectile. We found that the differences in mechanical properties between regions of the meteorite, which increase or reduce the efficiency of impacts, are not a result of compositional differences. A low mean particle size, attributed to repetitive shock, can increase hardness, while low porosity promotes a higher momentum multiplication. Momentum multiplication is the ratio between the change in momentum of a target due to an impact, and the momentum of the projectile, and therefore higher values imply more efficient impacts. In the Chelyabinsk meteorite the properties of the light-colored lithology materials facilitate obtaining higher momentum multiplication values, compared to the other regions described for this meteorite. Also, we found a low value of fracture toughness in the shock-melt veins of Chelyabinsk, which would promote the ejection of material after an impact and therefore increase the momentum multiplication. These results are relevant in the context of a future mission to test asteroid deflection, currently being studied by ESA and NASA: the Asteroid Impact and Deflection Assessment (AIDA) mission

    Polarimetry of binary systems: polars, magnetic CVs, XRBs

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    Polarimetry provides key physical information on the properties of interacting binary systems, sometimes difficult to obtain by any other type of observation. Indeed, radiation processes such as scattering by free electrons in the hot plasma above accretion discs, cyclotron emission by mildly relativistic electrons in the accretion shocks on the surface of highly magnetic white dwarfs and the optically thin synchrotron emission from jets can be observed. In this review, I will illustrate how optical/near-infrared polarimetry allows one to estimate magnetic field strengths and map the accretion zones in magnetic Cataclysmic Variables as well as determine the location and nature of jets and ejection events in X-ray binaries.Comment: 26 pages, 16 figures; to be published in Astrophysics and Space Science Library 460, Astronomical Polarisation from the Infrared to Gamma Rays, Editors: Mignani, R., Shearer, A., S{\l}owikowska, A., Zane,

    Deep-sequencing reveals broad subtype-specific HCV resistance mutations associated with treatment failure

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    A percentage of hepatitis C virus (HCV)-infected patients fail direct acting antiviral (DAA)-based treatment regimens, often because of drug resistance-associated substitutions (RAS). The aim of this study was to characterize the resistance profile of a large cohort of patients failing DAA-based treatments, and investigate the relationship between HCV subtype and failure, as an aid to optimizing management of these patients. A new, standardized HCV-RAS testing protocol based on deep sequencing was designed and applied to 220 previously subtyped samples from patients failing DAA treatment, collected in 39 Spanish hospitals. The majority had received DAA-based interferon (IFN) a-free regimens; 79% had failed sofosbuvir-containing therapy. Genomic regions encoding the nonstructural protein (NS) 3, NS5A, and NS5B (DAA target regions) were analyzed using subtype-specific primers. Viral subtype distribution was as follows: genotype (G) 1, 62.7%; G3a, 21.4%; G4d, 12.3%; G2, 1.8%; and mixed infections 1.8%. Overall, 88.6% of patients carried at least 1 RAS, and 19% carried RAS at frequencies below 20% in the mutant spectrum. There were no differences in RAS selection between treatments with and without ribavirin. Regardless of the treatment received, each HCV subtype showed specific types of RAS. Of note, no RAS were detected in the target proteins of 18.6% of patients failing treatment, and 30.4% of patients had RAS in proteins that were not targets of the inhibitors they received. HCV patients failing DAA therapy showed a high diversity of RAS. Ribavirin use did not influence the type or number of RAS at failure. The subtype-specific pattern of RAS emergence underscores the importance of accurate HCV subtyping. The frequency of “extra-target” RAS suggests the need for RAS screening in all three DAA target regions

    HTLV-1 infection in solid organ transplant donors and recipients in Spain

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    HTLV-1 infection is a neglected disease, despite infecting 10-15 million people worldwide and severe illnesses develop in 10% of carriers lifelong. Acknowledging a greater risk for developing HTLV-1 associated illnesses due to immunosuppression, screening is being widely considered in the transplantation setting. Herein, we report the experience with universal HTLV testing of donors and recipients of solid organ transplants in a survey conducted in Spain. All hospitals belonging to the Spanish HTLV network were invited to participate in the study. Briefly, HTLV antibody screening was performed retrospectively in all specimens collected from solid organ donors and recipients attended since the year 2008. A total of 5751 individuals were tested for HTLV antibodies at 8 sites. Donors represented 2312 (42.2%), of whom 17 (0.3%) were living kidney donors. The remaining 3439 (59.8%) were recipients. Spaniards represented nearly 80%. Overall, 9 individuals (0.16%) were initially reactive for HTLV antibodies. Six were donors and 3 were recipients. Using confirmatory tests, HTLV-1 could be confirmed in only two donors, one Spaniard and another from Colombia. Both kidneys of the Spaniard were inadvertently transplanted. Subacute myelopathy developed within 1 year in one recipient. The second recipient seroconverted for HTLV-1 but the kidney had to be removed soon due to rejection. Immunosuppression was stopped and 3 years later the patient remains in dialysis but otherwise asymptomatic. The rate of HTLV-1 is low but not negligible in donors/recipients of solid organ transplants in Spain. Universal HTLV screening should be recommended in all donor and recipients of solid organ transplantation in Spain. Evidence is overwhelming for very high virus transmission and increased risk along with the rapid development of subacute myelopathy
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