8 research outputs found

    Sistemas supramoleculares dador-aceptor basados en nanoestructuras de carbono

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    Uno de los objetivos de la ciencia es la búsqueda de fuentes de energía alternativas para solucionar la demanda cada vez más creciente de energía. Una fuente de enrgía inagotable a tener en cuenta es el sol. De ahí que el diseño de sistemas fotosintétivos artificiales capaces de absorber la energía solar para su conversión en energía eléctrica, sea una de las aproximaciones más desarrolladas en las últimas décadas.Objetivos. Capítulo 1: estudiar los procesos de transferencia electrónica fotoinducida en una nueva serie de díadas y tríadas supramoleculares, basadas en fullereno y SWCNTs, como unidades aceptoras de electrones, y porfirina y tetratiafulvaleno pi extendido como unidades dadoras de electrones.Capítulo 2: Síntesis de nuevos agregados helicoidales basadoso en moléculas discóticas con simetría c3 funcionalizados con unidades de porfirinas, para su aplicación en dispositivos optoelectrónicos.Resultados y discusiónCapítulo 1Tríadas supramoleculares dsa basadas en oligo p fenileno de diferente longitud como espaciador.En la primera parte de la presente memoria, se diseñó y sintetizó como unidad aceptora de electrones, una serie de derivados de fullereno covalentemente unido a un espaciador de tipo oligo p fenileno de diferente longitud con un grupo ácido en posición terminal. También se llevó a cabo la síntesis de la unidad complementaria dadora de electrones basada en porfirina o tetratiafulvaleno pi extendido funcionalizada con un grupo amidina. El estudio de la formación del complejo supramolecular dsa se desarrollo a través de diferentes técnicas espectroscópicas tales como UV vis y fluorescencia. Estos estudios revelaron la formación del complejo supramolecular con constantes de asociación en el orden de 10 10 m. Estos valores tan altos de la constante de asociación están asociados al fuerte carácter electrostático del enlace carboxilato-amidina. Además, los estudios fotofísicos mostraron que existía un proceso de transferencia electrónica fotoinducida entre las unidades elctroactivas, con tiempos de vida del estado con separación de cargas en el orden de nanosegundos. También se evaluó el comportamiento como cable molecular del sistema oligo p fenileno obteniéndose valores para el factor de atenuación..

    Modifying the catalytic activity of lipopeptide assemblies with nucleobases

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    Biohybrid catalysts that operate in aqueous media are intriguing for systems chemistry. In this paper, we investigate whether control over the self-assembly of biohybrid catalysts can tune their properties. As a model, we use the catalytic activity of functional hybrid molecules consisting of a catalytic H-dPro-Pro-Glu tripeptide, derivatized with fatty acid and nucleobase moieties. This combination of simple biological components merged the catalytic properties of the peptide with the self-assembly of the lipid, and the structural ordering of the nucleobases. The biomolecule hybrids self-assemble in aqueous media into fibrillar assemblies and catalyze the reaction between butanal and nitrostyrene. The interactions between the nucleobases enhanced the order of the supramolecular structures and affected their catalytic activity and stereoselectivity. The results point to the significant control and ordering that nucleobases can provide in the self-assembly of biologically inspired supramolecular catalystsPID2020-119306GB-I00, S2018/NMT-4291 TEC2SPACE, CSIC13-4E-179

    Programmed Recognition between Complementary Dinucleolipids To Control the Self-Assembly of Lipidic Amphiphiles

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    This is the peer reviewed version of the following article: Morales‐Reina, S., Giri, C., Leclercq, M., Vela‐Gallego, S., de la Torre, I., Caston, J. R., ... & de la Escosura, A. (2020). Programmed Recognition between Complementary Dinucleolipids To Control the Self‐Assembly of Lipidic Amphiphiles. Chemistry–A European Journal, 26(5), 1082-1090, which has been published in final form at https://doi.org/10.1002/chem.201904217. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions.One of the major goals in systems chemistry is to create molecular assemblies with emergent properties that are characteristic of life. An interesting approach toward this goal is based on merging different biological building blocks into synthetic systems with properties arising from the combination of their molecular components. The covalent linkage of nucleic acids (or their constituents: nucleotides, nucleosides and nucleobases) with lipids in the same hybrid molecule leads, for example, to the so-called nucleolipids. Herein, we describe nucleolipids with a very short sequence of two nucleobases per lipid, which, in combination with hydrophobic effects promoted by the lipophilic chain, allow control of the self-assembly of lipidic amphiphiles to be achieved. The present work describes a spectroscopic and microscopy study of the structural features and dynamic self-assembly of dinucleolipids that contain adenine or thymine moieties, either pure or in mixtures. This approach leads to different self-assembled nanostructures, which include spherical, rectangular and fibrillar assemblies, as a function of the sequence of nucleobases and chiral effects of the nucleolipids involved. We also show evidence that the resulting architectures can encapsulate hydrophobic molecules, revealing their potential as drug delivery vehicles or as compartments to host interesting chemistries in their interior.Research in Madrid received support from the Spanish Ministry of Economy and Competitivity (MINECO: CTQ‐2014‐53673‐P, CTQ‐2017‐89539‐P, and EUIN2017‐87022). This work was also supported in part by grants to JRC from MINECO (BFU2017‐88736‐R), and Comunidad Autónoma de Madrid (P2018/NMT‐4389). A.d.l.E. and M.S. thank the interdisciplinary framework provided by the European COST Action CM1304 (“Emergence and evolution of complex chemical systems”). A.d.l.E. and C.G. acknowledge the “Programme for Post‐Doctoral Talent Attraction to CEI UAM+CSIC—Intertalentum” (GA 713366). Research in Mons was supported by the Wallonia Region and the Fund for Scientific Research (FNRS, Belgium) under the grants MIS No. F.4532.16 (SHERPA) and EOS No. 30650939 (PRECISION). Confocal fluorescence microscopy was performed with the help of Sylvia Gutierrez Erlandsson, from the Advanced Light Microscopy Service of Centro Nacional de Biotecnologia (CNB). The professional editing service NB Revisions was used for technical preparation of the text prior to submission

    Colombian consensus recommendations for diagnosis, management and treatment of the infection by SARS-COV-2/ COVID-19 in health care facilities - Recommendations from expert´s group based and informed on evidence

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    La Asociación Colombiana de Infectología (ACIN) y el Instituto de Evaluación de Nuevas Tecnologías de la Salud (IETS) conformó un grupo de trabajo para desarrollar recomendaciones informadas y basadas en evidencia, por consenso de expertos para la atención, diagnóstico y manejo de casos de Covid 19. Estas guías son dirigidas al personal de salud y buscar dar recomendaciones en los ámbitos de la atención en salud de los casos de Covid-19, en el contexto nacional de Colombia

    Collective adaptability in a replication network of minimal nucleobase sequences

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    A major challenge for understanding the origins of life is to explore how replication networks can engage in an evolutionary process. Herein, we shed light on this problem by implementing a network constituted by two different types of extremely simple biological components: the amino acid cysteine and the canonical nucleobases adenine and thymine, connected through amide bonds to the cysteine amino group and oxidation of its thiol into three possible disulfides. Supramolecular and kinetic analyses revealed that both self- and mutual interactions between such dinucleobase compounds drive their assembly and replication pathways. Those pathways involving sequence complementarity led to enhanced replication rates, suggesting a potential bias for selection. The interplay of synergistic dynamics and competition between replicators was then simulated, under conditions that are not easily accessible with experiments, in an open reactor parametrized and constrained with the unprecedentedly complete experimental kinetic data obtained for our replicative network. Interestingly, the simulations show bistability, as a selective amplification of different species depending on the initial mixture composition. Overall, this network configuration can favor a collective adaptability to changes in the availability of feedstock molecules, with disulfide exchange reactions serving as 'wires' that connect the different individual auto- and cross-catalytic pathway

    The protometabolic nature of prebiotic chemistry

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    The field of prebiotic chemistry has been dedicated over decades to finding abiotic routes towards the molecular components of life. There is nowadays a handful of prebiotically plausible scenarios that enable the laboratory synthesis of most amino acids, fatty acids, simple sugars, nucleotides and core metabolites of extant living organisms. The major bottleneck then seems to be the self-organization of those building blocks into systems that can self-sustain. The purpose of this tutorial review is having a close look, guided by experimental research, into the main synthetic pathways of prebiotic chemistry, suggesting how they could be wired through common intermediates and catalytic cycles, as well as how recursively changing conditions could help them engage in self-organized and dissipative networks/assemblies (i.e., systems that consume chemical or physical energy from their environment to maintain their internal organization in a dynamic steady state out of equilibrium). In the article we also pay attention to the implications of this view for the emergence of homochirality. The revealed connectivity between those prebiotic routes should constitute the basis for a robust research program towards the bottom-up implementation of protometabolic systems, taken as a central part of the origins-of-life problem. In addition, this approach should foster further exploration of control mechanisms to tame the combinatorial explosion that typically occurs in mixtures of various reactive precursors, thus regulating the functional integration of their respective chemistries into self-sustaining protocellular assemblies.This work was funded by the Spanish Agencia Estatal de Investigación (PID2020-119306GB-100 (AdlE); PID2019-104576GB-100 (KRM)) and the European Union (CLASSY project, Horizon 2020 research and innovation programme, Grant Agreement No. 862081 (AdlE); CORENET project, supported by the Swiss State Secretariat for Education, Research and Innovation (SERI), Grant Agreement No. 101046294 (AdlE); and ProtoMet project, Grant Agreement No. 813873 (KRM). Views and opinions expressed are however those of the authors only and do not necessarily reflect those of the European Union or the European Innovation Council and SME’s Executive Agency (EISMEA). Neither the European Union nor the granting authority can be held responsible for them. KRM also acknowledges support from the Basque Government (IT1668-22) and the John Templeton Foundation (grant 62220).Peer reviewe

    Characteristics, complications and outcomes among 1549 patients hospitalised with COVID-19 in a secondary hospital in Madrid, Spain: a retrospective case series study

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    Objectives To describe demographic, clinical, radiological and laboratory characteristics, as well as outcomes, of patients admitted for COVID-19 in a secondary hospital.Design and setting Retrospective case series of sequentially hospitalised patients with confirmed SARS-CoV-2, at Infanta Leonor University Hospital (ILUH) in Madrid, Spain.Participants All patients attended at ILUH testing positive to reverse transcriptase-PCR on nasopharyngeal swabs and diagnosed with COVID-19 between 1 March 2020 and 28 May 2020.Results A total of 1549 COVID-19 cases were included (median age 69 years (IQR 55.0–81.0), 57.5% men). 78.2% had at least one underlying comorbidity, the most frequent was hypertension (55.8%). Most frequent symptoms at presentation were fever (75.3%), cough (65.7%) and dyspnoea (58.1%). 81 (5.8%) patients were admitted to the intensive care unit (ICU) (median age 62 years (IQR 51–71); 74.1% men; median length of stay 9 days (IQR 5–19)) 82.7% of them needed invasive ventilation support. 1393 patients had an outcome at the end of the study period (case fatality ratio: 21.2% (296/1393)). The independent factors associated with fatality (OR; 95% CI): age (1.07; 1.06 to 1.09), male sex (2.86; 1.85 to 4.50), neurological disease (1.93; 1.19 to 3.13), chronic kidney disease (2.83; 1.40 to 5.71) and neoplasia (4.29; 2.40 to 7.67). The percentage of hospital beds occupied with COVID-19 almost doubled (702/361), with the number of patients in ICU quadrupling its capacity (32/8). Median length of stay was 9 days (IQR 6–14).Conclusions This study provides clinical characteristics, complications and outcomes of patients with COVID-19 admitted to a European secondary hospital. Fatal outcomes were similar to those reported by hospitals with a higher level of complexity

    Non-motor symptoms burden, mood, and gait problems are the most significant factors contributing to a poor quality of life in non-demented Parkinson's disease patients: Results from the COPPADIS Study Cohort

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    [Objective] To identify factors related to a poor health-related and global quality of life (QoL) in a cohort of non-demented Parkinson's disease (PD) patients and compare to a control group.[Methods] The data correspond to the baseline evaluation of the COPPADIS-2015 Study, an observational, 5-year follow-up, multicenter, evaluation study. Three instruments were used to assess QoL: (1) the 39-item Parkinson's disease Questionnaire (PDQ-39), (2) a subjective rating of global QoL (PQ-10), and (3) the EUROHIS-QOL 8-item index (EUROHIS-QOL8). Multiple linear regression methods were used to evaluate the direct impact of different variables on these QoL measures.[Results] QoL was worse in PD patients (n = 692; 62.6 ± 8.9 years old, 60.3% males) than controls (n = 206; 61 ± 8.3 years old, 49.5% males): PDQ-39, 17.1 ± 13.5 vs 4.4 ± 6.3 (p < 0.0001); PQ-10, 7.3 ± 1.6 vs 8.1 ± 1.2 (p < 0.0001); EUROHIS-QOL8, 3.8 ± 0.6 vs 4.2 ± 0.5 (p < 0.0001). A high correlation was observed between PDQ-39 and Non-Motor Symptoms Scale (NMSS) (r = 0.72; p < 0.0001), and PDQ-39 and Beck Depression Inventory-II (BDI-II) (r = 0.65; p < 0.0001). For health-related QoL (PDQ-39), non-motor symptoms burden (NMSS), mood (BDI-II), and gait problems (Freezing Of Gait Questionnaire [FOGQ]) provided the highest contribution to the model (β = 0.32, 0.28, and 0.27, respectively; p < 0.0001); whereas mood and gait problems contributed the most to global QoL (PQ-10, β = -0.46 and −0.21, respectively; EUROHIS-QOL8, β = -0.44 and −0.23, respectively).[Conclusions] QoL is worse in PD patients than in controls. Mood, non-motor symptoms burden, and gait problems seem to be the most relevant factors affecting health-related and global perceived QoL in non-demented PD patients.Peer reviewe
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