1,713 research outputs found

    Photoinduced energy transfer in ZnCdSeS quantum dot-phthalocyanines hybrids

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    In this article, interaction between ZnCdSeS quantum dot (QD) and phthalocyanines with variable linker has been reported. Steady-state and time-resolved spectroscopic investigation reveals that only photoinduced energy transfer occurs from QD to phthalocyanines. To evaluate quantitatively the energy transfer, the Poisson statistics of QD-dye complex formation was used in the analysis of steady-state and time-resolved emission quenching, which allows to estimate the energy transfer rate constant for an ideal one-to-one complex. The measured rate constants are compared to the rates evaluated based on the classic Förster theory, which shows roughly 1 nm discrepancy in the energy transfer distance estimation, or one order in magnitude discrepancy in the transfer rate constants.S.M. is grateful to the TUT postdoctoral programme. T.T. is grateful for the financial support of the MINECO, Spain (CTQ2017-85393-P), the Comunidad de Madrid (FOTOCARBON, S2013/MIT-2841). IMDEA Nanociencia acknowledges support from the ‘Severo Ochoa’ Programme for Centres of Excellence in R&D (MINECO, Grant SEV-2016-0686)

    An insight into transfer hydrogenation reactions catalysed by iridium(iii) bis-n-heterocyclic carbenes

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    A variety of [M(L)2(L')2{kC,C'-bis(NHC)}]BF4 complexes (M = Rh or Ir; L = CH3CN or wingtip group; L' = I– or CF3COO–; NHC=N-heterocyclic carbene) have been tested as pre-catalysts for the transfer hydrogenation of ketones and imines. The conversions and TOF's obtained are closely related to the nature of the ligand system and metal centre, more strongly coordinating wingtip groups yielding more active and recyclable catalysts. Theoretical calculations at the DFT level support a classic stepwise metal-hydride pathway against the concerted Meerwein–Ponndorf–Verley (MPV) mechanism. The calculated catalytic cycle involves a series of ligand rearrangements due to the high trans effect of the carbene and hydrido ligands, which are more stable when situated in mutual cis positions. The reaction profiles obtained for the complexes featuring an iodide or a trifluoroacetate in one of the apical positions agree well with the relative activity observed for both catalysts

    Including coronary ostia in patient-specific 3D models of the whole aortic valve apparatus, derived from TEE, for biomechanical simulations

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    There is an increasing interest in the numerical modeling and simulation of the aortic valve behavior and functioning, on the different stages involved as healthy, stenotic or replacement procedure. As echocardiography is a ubiquitous and economic modality, the geometric model construction based on such images is therefore of major interest. In this paper, a new patient-specific approach for modeling the complete aortic valve apparatus - derived from parameters extracted from 3D transesophageal echocardiographs -that includes for the first time the left ventricle outflow tract and the coronary ostia, both crucial for proper assessment of valve biomechanical behavior, is presented. An innovative method for characterizing coronary pressures from patient-specific clinical data, to be used as boundary conditions for the numerical simulation is also described. Results from experiments were presented to evaluate the novel aspects of the model, that permits to compare the existing models (non-coronary model NCM) and the proposed new coronary model (CM). Variations of displacement and stress on each leaflet prove the need of considering leaflet asymmetry. Computed quantities in the results sections are within the range of physiological data. This permits to conclude that the proposed aortic valve apparatus model of the aortic valve apparatus improves on previous ones by considering this extremely complex structure in greater detail.Xunta de Galicia | Ref. IN606A-2017/02

    Dengue virus targets RBM10 deregulating host cell splicing and innate immune response

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    © The Author(s) 2020. Published by Oxford University Press on behalf of Nucleic Acids Research. This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/4.0/), which permits non-commercial re-use, distribution, and reproduction in any medium, provided the original work is properly cited. For commercial re-use, please contact [email protected] experiments previously performed by our laboratories showed enrichment in intronic sequences and alterations in alternative splicing in dengue-infected human cells. The transcript of the SAT1 gene, of well-known antiviral action, displayed higher inclusion of exon 4 in infected cells, leading to an mRNA isoform that is degraded by non-sense mediated decay. SAT1 is a spermidine/spermine acetyl-transferase enzyme that decreases the reservoir of cellular polyamines, limiting viral replication. Delving into the molecular mechanism underlying SAT1 pre-mRNA splicing changes upon viral infection, we observed lower protein levels of RBM10, a splicing factor responsible for SAT1 exon 4 skipping. We found that the dengue polymerase NS5 interacts with RBM10 and its sole expression triggers RBM10 proteasome-mediated degradation. RBM10 over-expression in infected cells prevents SAT1 splicing changes and limits viral replication, while its knock-down enhances the splicing switch and also benefits viral replication, revealing an anti-viral role for RBM10. Consistently, RBM10 depletion attenuates expression of interferon and pro-inflammatory cytokines. In particular, we found that RBM10 interacts with viral RNA and RIG-I, and even promotes the ubiquitination of the latter, a crucial step for its activation. We propose RBM10 fulfills diverse pro-inflammatory, anti-viral tasks, besides its well-documented role in splicing regulation of apoptotic genes.Agencia Nacional de Promoción Científica y Tecnológica de Argentina (ANPCyT) [2014-2888, 2015-1731, 2017-0111 to A.S. and 2015-2555, 2017-1717 to A.V.G.]; Universidad de Buenos Aires, Argentina (UBACyT) [20020170100045BA to A.S.]; NIH (NIAID) [R01.AI095175 to A.V.G.]; Consejo Nacional de Investigaciones Científicas y Técnicas de Argentina (CONICET) [PIP 11220170100171CO to C.C.G]; B.P. has been a postdoctoral fellow from CONICET from 2017 to 2019 and is currently a postdoctoral fellow at the Institute of Cell Biology in the University of Bern, Switzerland; L.B. and M.E.G.S. are recipients of doctoral fellowships from CONICET; M.F.T. is a doctoral fellowship recipient from ANPCyT; N.G. has been an undergraduate fellowship recipient from the University of Buenos Aires (2018–2020); P.M. has been a doctoral fellow from CONICET (2015–2019) and is currently a postdoctoral fellow supported by H2020-Marie Sklodowska-Curie Research and Innovation Staff Exchanges [734825-LysoMod]; R.V.D. has been a visiting post-doctoral fellow at the Srebrow lab from IMM (Lisbon, Portugal) supported by the same program. A.S., A.V.G., C.C.G., N.G.I. and L.G.G. are career investigators from CONICET.info:eu-repo/semantics/publishedVersio

    Falls rate increase and foot dorsal flexion limitations are exhibited in patients who suffer from asthma: A novel case-control study

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    [Abstract] Purpose: Based on the possible association between reduced foot dorsiflexion and high risk of falls, the main objective was to determine the ankle and 1º metatarsophalangeal joint (1stMTTP) dorsiflexion range of motion and falls rate in patients with asthma compared to healthy matched-paired controls. Methods: A case-control study was carried out. Eighty participants were recruited and divided into patients with asthma (case group; n=40) and matched-paired healthy participants (control group; n=40). Foot dorsal flexion range of motion (assessed by the Weight-Bearing Lunge Test [WBLT]) and falls rate (evaluated as falls number during the prior year) were considered as the primary outcomes. Indeed, ankle dorsiflexion was measured by a mobile app (º) and a tape measure (cm) as well as 1stMTTP dorsiflexion was determined by and universal goniometer (º). Results: Statistically significant differences (P.05). Conclusions: These study findings showed that a falls rate increase and bilateral foot dorsal flexion limitations of the ankle and 1stMTTP joints are exhibited in patients who suffer from asthma

    Panoramic Endocardial Optical Mapping Demonstrates Serial Rotors Acceleration and Increasing Complexity of Activity During Onset of Cholinergic Atrial Fibrillation.

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    BACKGROUND: Activation during onset of atrial fibrillation is poorly understood. We aimed at developing a panoramic optical mapping system for the atria and test the hypothesis that sequential rotors underlie acceleration of atrial fibrillation during onset. METHODS AND RESULTS: Five sheep hearts were Langendorff perfused in the presence of 0.25 μmol/L carbachol. Novel optical system recorded activations simultaneously from the entire left and right atrial endocardial surfaces. Twenty sustained (>40 s) atrial fibrillation episodes were induced by a train and premature stimuli protocol. Movies obtained immediately (Initiation stage) and 30 s (Early Stabilization stage) after premature stimulus were analyzed. Serial rotor formation was observed in all sustained inductions and none in nonsustained inductions. In sustained episodes maximal dominant frequency increased from (mean±SD) 11.5±1.74 Hz during Initiation to 14.79±1.30 Hz at Early Stabilization (P<0.0001) and stabilized thereafter. At rotor sites, mean cycle length (CL) during 10 prerotor activations increased every cycle by 0.53% (P=0.0303) during Initiation and 0.34% (P=0.0003) during Early Stabilization. In contrast, CLs at rotor sites showed abrupt decreases after the rotors appearances by a mean of 9.65% (P<0.0001) during both stages. At Initiation, atria-wide accelerations and decelerations during rotors showed a net acceleration result whereby post-rotors atria-wide minimal CL (CLmin) were 95.5±6.8% of the prerotor CLmin (P=0.0042). In contrast, during Early Stabilization, there was no net acceleration in CLmin during accelerating rotors (prerotor=84.9±11.0% versus postrotor=85.8±10.8% of Initiation, P=0.4029). Levels of rotor drift distance and velocity correlated with atria-wide acceleration. Nonrotor phase singularity points did not accelerate atria-wide activation but multiplied during Initiation until Early Stabilization. Increasing number of singularity points, indicating increased complexity, correlated with atria-wide CLmin reduction (P<0.0001). CONCLUSIONS: Novel panoramic optical mapping of the atria demonstrates shortening CL at rotor sites during cholinergic atrial fibrillation onset. Atrial fibrillation acceleration toward Early Stabilization correlates with the net result of atria-wide accelerations during drifting rotors activity.post-print3906 K

    Evidence of galaxy interaction in the Narrow-line Seyfert 1 galaxy IRAS17020+4544 seen by NOEMA

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    The narrow-line Seyfert 1 galaxy IRAS17020+4544 is one of the few sources where both an X-ray ultra-fast outflow and a molecular outflow were observed to be consistent with energy conservation. However, IRAS17020+4544 is less massive and has a much more modest active galactic nucleus (AGN) luminosity than the other examples. Using recent CO(1-0) observations with the NOrthern Extended Millimeter Array (NOEMA), we characterised the molecular gas content of the host galaxy for the first time. We found that the molecular gas is distributed into an apparent central disc of 1.1x10^9 Msun, and a northern extension located up to 8 kpc from the centre with a molecular gas mass M_H2~10^8 Msun. The molecular gas mass and the CO dynamics in the northern extension reveal that IRAS 17020+4544 is not a standard spiral galaxy, instead it is interacting with a dwarf object corresponding to the northern extension. This interaction possibly triggers the high accretion rate onto the super massive black hole. Within the main galaxy, which hosts the AGN, a simple analytical model predicts that the molecular gas may lie in a ring, with less molecular gas in the nuclear region. Such distribution may be the result of the AGN activity which removes or photodissociates the molecular gas in the nuclear region (AGN feedback). Finally, we have detected a molecular outflow of mass M_H2=(0.7-1.2)x10^7 Msun in projection at the location of the northern galaxy, with a similar velocity to that of the massive outflow reported in previous millimeter data obtained by the Large Millimeter Telescope.Comment: Published in MNRAS, Volume 501, Issue 1, Pages 219-22

    Informe sobre la situación actual de los titulados superiores y técnicos especialistas de grado medio de los OPIs adscritos al Consejo Superior de Investigaciones Científicas

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    28 páginas. Este informe no se encuentra clasificado en ninguna colección. Se presentó ante el Secretario de Estado de Universidades e Investigación del Ministerio de Educación y Ciencia y ante el Presidente del C.S.I.C. El grupo de trabajo que ha elaborado el presente documento está formado, en su totalidad, por funcionarios adscritos al CSIC pertenecientes a las escalas de Titulados Superiores Especializados y Técnicos Especialistas de Grado Medio de los OPIs, con titulaciones universitarias (Licenciados, Ingenieros, Ingenieros Técnicos) e incluso grado de Doctor.Tras la reunión mantenida en Madrid el día 18 de enero de 2005 por un grupo de 9 personas pertenecientes a las Escalas de Técnicos Especialistas de Grado Medio (antes denominados Titulados Técnicos Especializados) y Titulados Superiores del Consejo Superior de Investigaciones Científicas (CSIC), con el Excmo. Sr. Secretario de Estado de Universidades e Investigación del Ministerio de Educación y Ciencia, D. Salvador Ordóñez Delgado, se ha elaborado el presente informe sobre la situación actual, propuestas de modificación sobre la promoción profesional y retribución económica de las Escalas Técnicas del CSIC, por petición expresa del Excmo. Sr. Secretario de Estado. En este informe se detalla la problemática que nos llevo a solicitar dicha reunión, y se presenta una propuesta de modificación de la actual RPT junto con una vía de promoción profesional y económica, con el debido reconocimiento del trabajo desarrollado por las Escalas Técnicas, tan poco reconocido dentro del máximo organismo de investigación en España, como es el Consejo Superior de Investigaciones Científicas.Peer reviewe

    Supporting data for the MS identification of distinct transferrin glycopeptide glycoforms and citrullinated peptides associated with inflammation or autoimmunity

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    This data article presents the results of all the statistical analyses applied to the relative intensities of the detected 2D-DiGE protein spots for each of the 3 performed DiGE experiments. The data reveals specific subsets of protein spots with significant differences between WT and CD38-deficient mice with either Collagen-induced arthritis (CIA), or with chronic inflammation induced by CFA, or under steady-state conditions. This article also shows the MS data analyses that allowed the identification of the protein species which serve to discriminate the different experimental groups used in this study. Moreover, the article presents MS data on the citrullinated peptides linked to specific protein species that were generated in CIA(+) or CFA-treated mice. Lastly, this data article provides MS data on the efficiency of the analyses of the transferrin (Tf) glycopeptide glycosylation pattern in spleen and serum from CIA(+) mice and normal controls. The data supplied in this work is related to the research article entitled "identification of multiple transferrin species in spleen and serum from mice with collagen-induced arthritis which may reflect changes in transferrin glycosylation associated with disease activity: the role of CD38" [1]. All mass spectrometry data have been deposited to the ProteomeXchange Consortium via the PRIDE partner repository with identifiers PRIDE: PXD002644, PRIDE: PXD002643, PRIDE: PXD003183 and PRIDE: PXD003163
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