143 research outputs found

    Life-history traits in an evergreen Mediterranean oak respond differentially to previous experimental environments

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    Living organisms respond both to current and previous environments, which can have important consequences on population dynamics. However, there is little experimental evidence based on long-term field studies of the effects of previous environments on the performance of individuals. We tested the hypothesis that trees that establish under different environmental conditions perform differently under similar post-establishment conditions. We used the slow-growing, evergreen Mediterranean oak <i>Quercus ilex</i> subsp. <i>rotundifolia</i> as target species. We analyzed the effects of previous environments, competition effects and tradeoffs among life-history traits (survival, growth, and reproduction). We enhanced seedling establishment for three years by reducing abiotic environmental harshness by means of summer irrigation and artificial shading in 12 experimental plots, while four plots remained as controls. Then these treatments were interrupted for ten years. Seedlings under ameliorated environmental conditions survived and grew faster during early establishment. During the post-management period, previous treatments 1) did not have any effect on survival, 2) experienced a slower above-ground growth, 3) decreased root biomass as indicated from reflectivity of Ground Penetration Radar, 4) increased acorn production mostly through a greater canopy volume and 5) increased acorn production effort. The trees exhibited a combination of effects related to acclimation for coping with abiotic stress and effects of intra-specific competition. In accordance with our hypothesis, tree performance overall depended on previous environmental conditions, and the response was different for different life-history traits. We recommend early management because it increased plot cover, shortened the time to attain sexual maturity and increased the amount of acorn production. Plots such as those assessed in this study may act as sources of propagules in deforested agricultural landscapes thus aiding natural establishment of new plants

    Facies generadoras de carbón en el Westfaliense superior de la Cuenca Carbonífera Central Asturiana

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    La Cuenca Carbonífera Central Asturiana constituye una cuenca de antepais individualizada en la Zona Cantábrica durante el Carbonifero Superior coincidiendo con la máxima actividad de la orogenia Hercinica. Durante el Westfaliense, se acumularon en ella importantes volúmenes de material clástico procedentes de los relieves en elevación situados al W. Los abanicos aluviales costeros constituyeron unos sistemas deposicionales muy eficientes en la dispersión de estos materiales, generaron extensas cuñas clásticas en relación con las cuales se originaron capas de carbón explotables. En este trabajo se estudian varios litosomas de edad Westfaliense Superior que representan episodios progradantes de estos sistemas sobre ambientes marinos someros v de transición. El análisis e interpretación de sus facies y geometrías permite la reconstrucción de las condiciones ambientales en que se generaron las capas de carbón asociadas a cada una de las unidades estudiadas. Estas se desarrollaron: 1) en zonas marginales a los lóbulos progradantes y zonas interlóbulos y 2) sobre los mismos una vez que éstos fueron abandonados y previamente a su enterramiento

    Specific Hsp100 chaperones determine the fate of the first enzyme of the plastidial isoprenoid pathway for either refolding or degradation by the stromal Clp protease in Arabidopsis

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    The lifespan and activity of proteins depend on protein quality control systems formed by chaperones and proteases that ensure correct protein folding and prevent the formation of toxic aggregates. We previously found that the Arabidopsis thaliana J-protein J20 delivers inactive (misfolded) forms of the plastidial enzyme deoxyxylulose 5-phosphate synthase (DXS) to the Hsp70 chaperone for either proper folding or degradation. Here we show that the fate of Hsp70-bound DXS depends on pathways involving specific Hsp100 chaperones. Analysis of individual mutants for the four Hsp100 chaperones present in Arabidopsis chloroplasts showed increased levels of DXS proteins (but not transcripts) only in those defec- tive in ClpC1 or ClpB3. However, the accumulated enzyme was active in the clpc1 mutant but inactive in clpb3 plants. Genetic evidence indicated that ClpC chaperones might be required for the unfolding of J20-delivered DXS protein coupled to degradation by the Clp protease. By contrast, biochemical and genetic approaches confirmed that Hsp70 and ClpB3 chaperones interact to collaborate in the refolding and activation of DXS. We conclude that specific J-proteins and Hsp100 chaperones act together with Hsp70 to recognize and deliver DXS to either reactivation (via ClpB3) or removal (via ClpC1) depending on the physiological status of the plastid

    Efficacy and safety assessment of different dosage of benznidazol for the treatment of Chagas disease in chronic phase in adults (MULTIBENZ study): Study protocol for a multicenter randomized Phase II non-inferiority clinical trial

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    Background: Chagas disease (CD) continues to be a neglected infectious disease with one of the largest burdens globally. Despite the modest cure rates in adult chronic patients and its safety profile, benznidazole (BNZ) is still the drug of choice. Its current recommended dose is based on nonrandomized studies, and efficacy and safety of the optimal dose of BNZ have been scarcely analyzed in clinical trials.Methods/design: MULTIBENZ is a phase II, randomized, noninferiority, double-blind, multicenter international clinical trial. A total of 240 patients with Trypanosoma CD in the chronic phase will be recruited in four different countries (Argentina, Brazil, Colombia, and Spain). Patients will be randomized to receive BNZ 150 mg/day for 60 days, 400 mg/day for 15 days, or 300 mg/day for 60 days (comparator arm). The primary outcome is the efficacy of three different BNZ therapeutic schemes in terms of dose and duration. Efficacy will be assessed according to the proportion of patients with sustained parasitic load suppression in peripheral blood measured by polymerase chain reaction. The secondary outcomes are related to pharmacokinetics and drug tolerability. The follow-up will be 12 months from randomization to end of study participation. Recruitment was started in April 2018.Conclusion: This is a clinical trial conducted for the assessment of different dose schemes of BNZ compared with the standard treatment regimen for the treatment of CD in the chronic phase. MULTIBENZ may help to clarify which is the most adequate BNZ regimen in terms of efficacy and safety, predicated on sustained parasitic load suppression in peripheral blood.Fil: Molina Morant, D.. Universidad Autónoma de Barcelona. Hospital Vall D' Hebron; EspañaFil: Fernández, M. L.. Dirección Nacional de Instituto de Investigación. Administración Nacional de Laboratorio e Instituto de Salud “Dr. C. G. Malbrán”. Instituto Nacional de Parasitología "Dr. Mario Fatala Chaben”; ArgentinaFil: Bosch Nicolau, P.. Universidad Autónoma de Barcelona. Hospital Vall D' Hebron; EspañaFil: Sulleiro, E.. Universidad Autónoma de Barcelona. Hospital Vall D' Hebron; EspañaFil: Bangher, M.. Instituto de Cardiologia de Corrientes Juana Francisca Cabral.; ArgentinaFil: Salvador, F.. Universidad Autónoma de Barcelona. Hospital Vall D' Hebron; EspañaFil: Sanchez Montalva, A.. Universidad Autónoma de Barcelona. Hospital Vall D' Hebron; EspañaFil: Ribeiro, A.L.P.. Universidade Federal de Minas Gerais; BrasilFil: De Paula, A.M.B.. Universidad Federal de Montes Claros; BrasilFil: Eloi, S.. Universidade Federal de Minas Gerais; BrasilFil: Oliveira Correa, Ronaldo. Fundación Oswaldo Cruz; BrasilFil: Villar, J. C.. Instituto de Cardiología; ColombiaFil: Sosa-Estani, Sergio Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Centro de Investigaciones en Epidemiología y Salud Pública. Instituto de Efectividad Clínica y Sanitaria. Centro de Investigaciones en Epidemiología y Salud Pública; ArgentinaFil: Molina, I.. Universidad Autónoma de Barcelona. Hospital Vall D' Hebron; Españ

    Gas exchange at whole plant level shows that a less conservative water use is linked to a higher performance in three ecologically distinct pine species

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    Increasing temperatures and decreasing precipitation in large areas of the planet as a consequence of global warming will affect plant growth and survival. However, the impact of climatic conditions will differ across species depending on their stomatal response to increasing aridity, as this will ultimately affect the balance between carbon assimilation and water loss. In this study, we monitored gas exchange, growth and survival in saplings of three widely distributed European pine species (Pinus halepensis, P. nigra and P. sylvestris) with contrasting distribution and ecological requirements in order to ascertain the relationship between stomatal control and plant performance. The experiment was conducted in a common garden environment resembling rainfall and temperature conditions that two of the three species are expected to encounter in the near future. In addition, gas exchange was monitored both at the leaf and at the whole-plant level using a transient-state closed chamber, which allowed us to model the response of the whole plant to increased air evaporative demand (AED). P. sylvestris was the species with lowest survival and performance. By contrast, P. halepensis showed no mortality, much higher growth (two orders of magnitude), carbon assimilation (ca. 14 fold higher) and stomatal conductance and water transpiration (ca. 4 fold higher) than the other two species. As a consequence, P. halepensis exhibited higher values of water-use efficiency than the rest of the species even at the highest values of AED. Overall, the results strongly support that the weaker stomatal control of P. halepensis, which is linked to lower stem water potential, enabled this species to maximize carbon uptake under drought stress and ultimately outperform the more water conservative P. nigra and P. sylvestris. These results suggest that under a hotter drought scenario P. nigra and P. sylvestris would very likely suffer increased mortality, whereas P. halepensis could maintain gas exchange and avoid water-induced growth limitation. This might ultimately foster an expansion of P. halepensis to higher latitudes and elevations.This work was supported by the projects ECOLPIN (AGL2011–24296) and Remedinal 3 (S2013/ MAE- 2719) of the Madrid Government, by a FPU fellowship from the Spanish Ministry of Education, Culture and Sport (FPU13/03410) to DS and by EU Marie Curie (FP7–2013-IOF-625988) fellowship to EPSC

    The plant traits that drive ecosystems: Evidence from three continents.

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    Question: A set of easily‐measured (‘soft’) plant traits has been identified as potentially useful predictors of ecosystem functioning in previous studies. Here we aimed to discover whether the screening techniques remain operational in widely contrasted circumstances, to test for the existence of axes of variation in the particular sets of traits, and to test for their links with ‘harder’ traits of proven importance to ecosystem functioning. Location: central‐western Argentina, central England, northern upland Iran, and north‐eastern Spain. Recurrent patterns of ecological specialization: Through ordination of a matrix of 640 vascular plant taxa by 12 standardized traits, we detected similar patterns of specialization in the four floras. The first PCA axis was identified as an axis of resource capture, usage and release. PCA axis 2 appeared to be a size‐related axis. Individual PCA for each country showed that the same traits remained valuable as predictors of resource capture and utilization in all of them, despite their major differences in climate, biogeography and land‐use. The results were not significantly driven by particular taxa: the main traits determining PCA axis 1 were very similar in eudicotyledons and monocotyledons and Asteraceae, Fabaceae and Poaceae. Links between recurrent suites of ‘soft’ traits and ‘hard’ traits: The validity of PCA axis 1 as a key predictor of resource capture and utilization was tested by comparisons between this axis and values of more rigorously established predictors (‘hard’ traits) for the floras of Argentina and England. PCA axis 1 was correlated with variation in relative growth rate, leaf nitrogen content, and litter decomposition rate. It also coincided with palatability to model generalist herbivores. Therefore, location on PCA axis 1 can be linked to major ecosystem processes in those habitats where the plants are dominant. Conclusion: We confirm the existence at the global scale of a major axis of evolutionary specialization, previously recognised in several local floras. This axis reflects a fundamental trade‐off between rapid acquisition of resources and conservation of resources within well‐protected tissues. These major trends of specialization were maintained across different environmental situations (including differences in the proximate causes of low productivity, i.e. drought or mineral nutrient deficiency). The trends were also consistent across floras and major phylogenetic groups, and were linked with traits directly relevant to ecosystem processes.Fil: Díaz, Sandra Myrna. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Hodgson, J.G.. The University. Department of Animal and Plant Sciences. Unit of Comparative Plant Ecology; Reino UnidoFil: Thompson, K.. The University. Department of Animal and Plant Sciences. Unit of Comparative Plant Ecology; Reino UnidoFil: Cabido, Marcelo Ruben. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Cornelissen, Johannes H. C.. Free University. Faculty Earth and Life Sciences. Department of Systems Ecology; Países BajosFil: Funes, Guillermo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Pérez Harguindeguy, Natalia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Vendramini, Fernanda. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Falczuk, Valeria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Zak, Marcelo Román. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Khoshnevi, M.. Research Institute of Forests and Rangelands; IránFil: Pérez Rontomé, M. C.. Instituto Pirenaico de Ecología; EspañaFil: Shirvani, F. A.. Research Institute of Forests and Rangelands; IránFil: Yazdani, S.. Research Institute of Forests and Rangelands; IránFil: Abbas Azimi, R. Research Institute of Forests and Rangelands; IránFil: Bogaard, A. The University. Department of Archaeology and Prehistory; Reino UnidoFil: Boustani, S.. Research Institute of Forests and Rangelands; IránFil: Charles, M.. The University. Department of Archaeology and Prehistory; Reino UnidoFil: Dehghan, M.. Research Institute of Forests and Rangelands; IránFil: de Torres Espuny, L.. Instituto Pirenaico de Ecología; EspañaFil: Guerrero Campo, J.. Instituto Pirenaico de Ecología; EspañaFil: Hynd, A.. The University. Department of Archaeology and Prehistory; Reino UnidoFil: Jones, G.. The University. Department of Archaeology and Prehistory; Reino UnidoFil: Kowsary, E.. Research Institute of Forests and Rangelands; Irán. Instituto Pirenaico de Ecología; EspañaFil: Kazemi Saeed, F.. Research Institute of Forests and Rangelands; IránFil: Maestro Martínez, M.. Instituto Pirenaico de Ecología; EspañaFil: Romo Diez, A.. Instituto Botanico de Barcelona; EspañaFil: Shaw, S.. Research Institute of Forests and Rangelands; Irán. The University. Department of Animal and Plant Sciences; Reino UnidoFil: Siavash, B.. Research Institute of Forests and Rangelands; IránFil: Villar Salvador, P.. Instituto Pirenaico de Ecología; Españ

    A Novel Circulating MicroRNA for the Detection of Acute Myocarditis.

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    The diagnosis of acute myocarditis typically requires either endomyocardial biopsy (which is invasive) or cardiovascular magnetic resonance imaging (which is not universally available). Additional approaches to diagnosis are desirable. We sought to identify a novel microRNA for the diagnosis of acute myocarditis. To identify a microRNA specific for myocarditis, we performed microRNA microarray analyses and quantitative polymerase-chain-reaction (qPCR) assays in sorted CD4+ T cells and type 17 helper T (Th17) cells after inducing experimental autoimmune myocarditis or myocardial infarction in mice. We also performed qPCR in samples from coxsackievirus-induced myocarditis in mice. We then identified the human homologue for this microRNA and compared its expression in plasma obtained from patients with acute myocarditis with the expression in various controls. We confirmed that Th17 cells, which are characterized by the production of interleukin-17, are a characteristic feature of myocardial injury in the acute phase of myocarditis. The microRNA mmu-miR-721 was synthesized by Th17 cells and was present in the plasma of mice with acute autoimmune or viral myocarditis but not in those with acute myocardial infarction. The human homologue, designated hsa-miR-Chr8:96, was identified in four independent cohorts of patients with myocarditis. The area under the receiver-operating-characteristic curve for this novel microRNA for distinguishing patients with acute myocarditis from those with myocardial infarction was 0.927 (95% confidence interval, 0.879 to 0.975). The microRNA retained its diagnostic value in models after adjustment for age, sex, ejection fraction, and serum troponin level. After identifying a novel microRNA in mice and humans with myocarditis, we found that the human homologue (hsa-miR-Chr8:96) could be used to distinguish patients with myocarditis from those with myocardial infarction. (Funded by the Spanish Ministry of Science and Innovation and others.).Supported by a grant (PI19/00545, to Dr. Martín) from the Ministry of Science and Innovation through the Carlos III Institute of Health–Fondo de Investigación Sanitaria; by a grant from the Biomedical Research Networking Center on Cardiovascular Diseases (to Drs. Martín, Sánchez-Madrid, and Ibáñez); by grants (S2017/BMD-3671-INFLAMUNE-CM, to Drs. Martín and Sánchez-Madrid; and S2017/BMD-3867-RENIM-CM, to Dr. Ibáñez) from Comunidad de Madrid; by a grant (20152330 31, to Drs. Martín, Sánchez-Madrid, and Alfonso) from Fundació La Marató de TV3; by grants (ERC-2011-AdG 294340-GENTRIS, to Dr. Sánchez-Madrid; and ERC-2018-CoG 819775-MATRIX, to Dr. Ibáñez) from the European Research Council; by grants (SAF2017-82886R, to Dr. Sánchez-Madrid; RETOS2019-107332RB-I00, to Dr. Ibáñez; and SAF2017-90604-REDT-NurCaMeIn and RTI2018-095928-BI00, to Dr. Ricote) from the Ministry of Science and Innovation; by Fondo Europeo de Desarrollo Regional (FEDER); and by a 2016 Leonardo Grant for Researchers and Cultural Creators from the BBVA Foundation to Dr. Martín. The National Center for Cardiovascular Research (CNIC) is supported by the Carlos III Institute of Health, the Ministry of Science and Innovation, the Pro CNIC Foundation, and by a Severo Ochoa Center of Excellence grant (SEV-2015-0505). Mr. Blanco-Domínguez is supported by a grant (FPU16/02780) from the Formación de Profesorado Universitario program of the Spanish Ministry of Education, Culture, and Sports. Ms. Linillos-Pradillo is supported by a fellowship (PEJD-2016/BMD-2789) from Fondo de Garantía de Empleo Juvenil de Comunidad de Madrid. Dr. Relaño is supported by a grant (BES-2015-072625) from Contratos Predoctorales Severo Ochoa para la Formación de Doctores of the Ministry of Economy and Competitiveness. Dr. Alonso-Herranz is supported by a fellowship from La Caixa–CNIC. Dr. Caforio is supported by Budget Integrato per la Ricerca dei Dipartimenti BIRD-2019 from Università di Padova. Dr. Das is supported by grants (UG3 TR002878 and R35 HL150807) from the National Institutes of Health and the American Heart Association through its Strategically Focused Research Networks.S
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