92 research outputs found

    From Induced-Fit Assemblies to Ternary Inclusion Complexes with Fullerenes in Corannulene-Based Molecular Tweezers

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    Producción CientíficaThe participation of the tether moiety in fullerene recognition of corannulene-based molecular tweezers is known to be an important factor. In the present work, we describe the synthesis of a set of fullerene receptors bearing two corannulene units located at a suitable distance to effectively interact with C60 and C70. The tether comprises a fluorene-like scaffold where an assortment of different groups with variable electronic properties has been grafted. The photophysical and electrochemical properties of all final compounds have been unveiled and correlated to the donor/acceptor (DA) nature of the tether. Despite these strong variations, their affinity toward fullerenes cannot be correlated in any way to simple DA behavior as the main contribution to the interaction correspond to London dispersion forces. We found, however, that the sulfur-derived subfamily is able to adapt better to the fullerene outer surface slightly increasing the charge transfer and electrostatic attractive interactions being the most outstanding example the case of thiophene 4-S with C70 as it is capable of forming a ternary 2:1 inclusion complex in solution with an electronic binding energy that offsets entropy and desolvation penalties typically associated with higher-order inclusion complexes.Ministerio de Ciencia, Innovación y Universidades (project (projects numbers PGC2018-096880-A-I00, MCIU/AEI/FEDER, UE, PGC2018-099470-B-I00, and MCIU/AEI/FEDER, UE

    Remagnetización alpina en la Serra del Cadí (Pirineo Oriental)

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    The eastern Pyrenees, particularly the Cadi Range, displays the less density and quality of paleomagnetic data of the chain. This paper revisited one of the central sections (Pobla de Lillet) where we have resampled Permian, Maastrichtian and Paleocene rocks. Best results were attained in the Permian red sandstones and in the Cretaceous limestones. In the Permian, two components with paleomagnetic meaning were identified. The high temperature component (up to 670 ° C) is similar to that defined in pioneering works, it appears to be primary and does not show significant rotations. The intermediate temperature component (up to 500 ° C), not identified in previous works, seems to be a syntectonic remagnetization with Alpine age. The characterization of rotations and the extension of this remagnetization (as an additional source of kinematics information) should be addressed in Permian rocks in future works since the paleomagnetic signal of Cenozoic rocks is of lower qualityTrabajo financiado con los Proyectos Pmag3Drest-CGL2009-14214 y DR3AM- CGL2014-55118 del MINECO y del 3DR3- PI165/09 del Gobierno de Aragón.Peer Reviewe

    Copper Complexes in the Promotion of Aldol Addition to Pyridine-2-carboxaldehyde: Synthesis of Homo- and Heteroleptic Complexes and Stereoselective Double Aldol Addition

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    Producción CientíficaCuCl2·2H2O and Cu(ClO4)2·6H2O are able to promote aldol addition of pyridine-2-carboxaldehyde (pyca) with acetone, acetophenone, or cyclohexenone under neutral and mild conditions. The general and simple one-pot procedure for the aldol addition to Cu(II) complexes accesses novel Cu complexes with a large variety of different structural motifs, from which the aldol-addition ligand can be liberated by treatment with NH3. Neutral heteroleptic complexes in which the ligand acts as bidentate, or homoleptic cationic complexes in which the ligand acts as tridentate can be obtained depending on the copper salt used. The key step in these reactions is the coordination of pyca to copper, which increases the electrophilic character of the aldehyde, with Cu(ClO4)2 leading to a higher degree of activation than CuCl2, as predicted by DFT calculations. A regio- and stereoselective double aldol addition of pyca in the reaction of Cu(ClO4)2·6H2O with acetone leads to the formation of a dimer copper complex in which the novel double aldol addition product acts as a pentadentate ligand. A possible mechanism is discussed. The work is supported by extensive crystallographic studies.2019-12-312019-12-31Ministerio de Economía, Industria y Competitividad (Project CTQ 2013-41067-P

    “Bajo Pluma de Mujer”: análisis de la correspondencia femenina a Miguel de Unamuno en el primer tercio del siglo xx

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    The figure and work of Miguel de Unamuno has been an object of investigative interest from different academic areas and perspectives. Of particular importance is the study of the correspon- dence that the Spanish thinker had with prominent personalities of his era. In this regard, one cannot overlook the rich legacy that exists in the Unamuno House-Museum, property of the University of Salamanca, which makes up the writer’s archive of correspondence, with over 25,000 letters. In this investigation, we have explored a field that had remained largely unknown: the correspondence that the former Rector of Salamanca received from the pen of relevant women in the first third of the 20th century. Through a content analysis of a selection of 40 women, we have studied the exchange of ideas that they expressed in their letters and which they wanted to share with the writer. The results elucidate clear connections between certain historical events linked to the figure of Unamuno and the sociological problems these women experienced.La figura y obra de Miguel de Unamuno han sido objeto de interés investigador desde diferentes áreas académicas y perspectivas. Entre ellas cabe destacar el estudio de la correspondencia que mantuvo el pensador español con personalidades importantes de su época. A este respecto, no se puede obviar el rico legado que existe en la Casa-Museo Unamuno, perteneciente a la Universidad de Salamanca, que compone el fondo epistolar del escritor, con más de 25.000 cartas. En esta investigación se realiza una aproximación a un campo en parte desconocido, como es la correspon- dencia que el antiguo rector salmantino recibió de la pluma de mujeres relevantes del primer tercio del siglo xx. A través de un análisis de contenido sobre una selección de 40 mujeres, se estudia el intercambio de ideas que plasmaron en sus epístolas y que querían compartir con el escritor. Los resultados visibilizan las conexiones con ciertos acontecimientos históricos ligados a la figura de Unamuno y con la problemática sociológica que vivieron esas mujeres

    Reversible adhesion by type IV pili leads to formation of permanent localized clusters

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    The formation of long-lived, multicellular clusters is a fundamental step in the physiopathology of many disease-causing bacteria. Experiments on abiotic surfaces suggest that bacterial colonization, including initial cluster formation, requires (1) irreversible adhesion, (2) cell proliferation, and (3) a phenotypic transition. However, here we show that on infection of a polarized MDCK epithelium, Pseudomonas aeruginosa (PA) forms long-lived – i.e., permanent – bacterial clusters without requiring irreversible adhesion, cell proliferation, or a phenotypic transition. By combining experiments and a mathematical model, we reveal that the cluster formation process is mediated by type IV pili (T4P). Furthermore, we unveil how T4P quantitatively operate during adhesion, finding that it is a stochastic process that involves an activation time, requires the retraction of pili, and results in reversible attachment. We explain how such reversible attachment process leads to the formation of permanent bacterial clusters and quantify the cluster growth dynamics.Fil: Pepe, María Victoria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Biotecnológicas. Universidad Nacional de San Martín. Instituto de Investigaciones Biotecnológicas; ArgentinaFil: Dea, Maria Celeste. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Biotecnológicas. Universidad Nacional de San Martín. Instituto de Investigaciones Biotecnológicas; ArgentinaFil: Genskowsky Vargas, Camila Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Biotecnológicas. Universidad Nacional de San Martín. Instituto de Investigaciones Biotecnológicas; ArgentinaFil: Capasso, Dario Nicolás. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Biotecnológicas. Universidad Nacional de San Martín. Instituto de Investigaciones Biotecnológicas; ArgentinaFil: Roset, Mara Sabrina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Biotecnológicas. Universidad Nacional de San Martín. Instituto de Investigaciones Biotecnológicas; ArgentinaFil: Jager, Adriana Valeria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Biotecnológicas. Universidad Nacional de San Martín. Instituto de Investigaciones Biotecnológicas; ArgentinaFil: Peruani San Román, Fernando Miguel. Cergy-paris Universite (cergy-paris Universite); FranciaFil: Kierbel, Arlinet Verónica. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Biotecnológicas. Universidad Nacional de San Martín. Instituto de Investigaciones Biotecnológicas; Argentin

    COVID-19 in Latin America: A Bibliometric Analysis of Scientific Publications in Health

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    The coronavirus disease (COVID-19) has become a global health crisis. The scientific community has responded with a sizable level of research and publications, many of which are beginning to be identified and analyzed in systematic reviews of the literature and bibliometric studies. No readily identifiable, comparable study focused on Latin American scientific literature has been undertaken thus far. Therefore, this article analyzes such literature, focused on COVID-19, and one that has been published in the scientific journals of the region. A search with the keyword “COVID-19” in the Scientific Electronic Library Online (SciELO) database resulted in the identification of 261 documents. Following PRISMA guidelines, the total number was reduced to 117 for the purpose of the bibliometric analysis (i.e., elimination of preprint duplicates). Such analysis resulted in the following findings: 69 publications were editorial or individual commentaries, and 48 were original articles. The male authors totaled 280, contrasted with 169 female authors. Two Brazilian journals led in the number of publications: Cadernos de Saúde Pública and Clinics. Even though the Latin American scientific productivity regarding COVID-19 is not well represented in the different databases of the region, it is expected that these scientific publications will achieve increased visibility in the coming months. The article emphasizes the importance of systematic and bibliographic reviews ofthe scientific literature in Latin America in orderto evaluate the public health achievements of the region.Fil: Gallegos de San Vicente, Miguel Omar. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto Rosario de Investigaciones en Ciencias de la Educación. Universidad Nacional de Rosario. Instituto Rosario de Investigaciones en Ciencias de la Educación; Argentina. Universidad Catolica de Maule; ChileFil: Cervigni, Mauricio Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto Rosario de Investigaciones en Ciencias de la Educación. Universidad Nacional de Rosario. Instituto Rosario de Investigaciones en Ciencias de la Educación; ArgentinaFil: Consoli, Andrés J.. University of California; Estados UnidosFil: Caicho Rodriguez, Tomás. Pontificia Universidad Católica de Perú; PerúFil: Polanco, Fernando Andrés. Universidad Nacional de San Luis. Facultad de Psicología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Martino, Pablo Luis. Universidad Nacional de Rosario. Facultad de Psicología. Secretaria de Ciencia y Tecnología. Centro de Investigación En Neurociencias de Rosario; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Castro Pecanha, Viviane. University of Chicago; Estados UnidosFil: Buergos Videla, Carmen. Universidad de Atacama.; ChileFil: Polanco Carrasco, Roberto. No especifíca;Fil: Cussinato, Adriana Marie. Universidad de Palermo; Argentina. Universidad Nacional de Rosario; Argentin

    Design of the nutritional therapy for overweight and obese Spanish adolescents conducted by registered dieticians: the EVASYON study

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    Background: Dietary treatment for obese adolescents should aim to ensure adequate growth and development, by reducing excessive fat mass accumulation, avoiding loss of lean body mass, improving well-being and selfesteem and preventing cyclical weight regain. The aim of this article is to describe the dietary intervention design and the methods used to evaluate nutritional knowledge and behavior in the EVASYON study (Development, implementation and evaluation of the efficacy of a therapeutic programme for overweight/obese adolescents). Methods/design: EVASYON is a multi-centre study conducted in 5 Spanish hospital settings (Granada, Madrid, Pamplona, Santander and Zaragoza), where 204 overweight/obese Spanish adolescents were treated in groups of 9 to 11 subjects over 20 visits. The study was implemented in two stages: an intensive, calorie-restricted period for the first 9 weeks, and an extensive body-weight follow-up period for the last 11 months. A moderate energy intake restriction was applied in the intensive period according to the degree of obesity, on the basis of a balanced diet supplying 50-55% of daily energy as carbohydrates; 30-35% as fats and 10-15% as proteins. In the intensive period, adolescents were prescribed both a fixed full-day meal plan for the first three weeks and a full day meal plan with different food-choices for 6 weeks. Later, adolescents received a flexible meal plan based on food exchanges for the follow-up period until the end of the trial. Data on food intake, dietary and meal-related habits and behavior were collected by means of dietary questionnaires. To analyse nutritional knowledge, adolescents were examined regarding nutrient concepts and food items for a healthy diet with the appropriate tools. Participants were given nutritional information with complementary teaching material, which was available on the EVASYON website (www.estudioevasyon.com). Discussion: The dietary intervention of the EVASYON programme with a moderate calorie restriction for a limi - ted period of time could be a good strategy in treating overweight and obese adolescents and that will be tested further. Moreover, combining fixed plan with free-choice menus may help adolescents and their families to make right decisions for every day meals

    Unmasking a new prognostic marker and therapeutic target from the GDNF-RET/PIT1/p14ARF/p53 pathway in acromegaly

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    Most of acromegaly is caused by a sporadic somatotropinoma and a couple of novel gene mutations responsible for somatotropinoma have recently been reported. To determine the cause of sporadic somatotropinoma in Japanese patients, we analyzed 61 consecutive Japanese patients with somatotropinoma without apparent family history. Comprehensive genetic analysis revealed that 31 patients harbored guanine nucleotide-binding protein, alpha stimulating (GNAS) mutations (50.8%) and three patients harbored aryl hydrocarbon receptor interacting protein (AIP) mutations (4.9%). No patients had G protein-coupled receptor 101 (GPR101) mutations. The patients in this cohort study were categorized into three groups of AIP, GNAS, and others and compared the clinical characteristics. The AIP group exhibited significantly younger age at diagnosis, larger tumor, and higher nadir GH during oral glucose tolerance test. In all patients with AIP mutation, macro- and invasive tumor was detected and repetitive surgery or postoperative medical therapy was needed. One case showed a refractory response to postoperative somatostatin analogue (SSA) but after the addition of cabergoline as combined therapy, serum IGF-I levels were controlled. The other case showed a modest response to SSA and the switching to cabergoline monotherapy was also effective. These data suggest that although resistance to SSA has been reported in patients with AIP mutations, the response to dopamine agonist (DA) may be retained. In conclusion, the cause of sporadic somatotropinoma in Japanese patients was comparable with the previous reports in Caucasians, patients with AIP mutations showed unique clinical characteristics, and DA may be a therapeutic option for patients with AIP mutations

    The Mutational Landscape of Circulating Tumor Cells in Multiple Myeloma

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    The development of sensitive and non-invasive ‘‘liquid biopsies’’ presents new opportunities for longitudinal monitoring of tumor dissemination and clonal evolution. The number of circulating tumor cells (CTCs) is prognostic in multiple myeloma (MM), but there is little information on their genetic features. Here, we have analyzed the genomic landscape of CTCs from 29 MM patients, including eight cases with matched/paired bone marrow (BM) tumor cells. Our results show that 100% of clonal mutations in patient BM were detected in CTCs and that 99% of clonal mutations in CTCs were present in BM MM. These include typical driver mutations in MM such as in KRAS, NRAS, or BRAF. These data suggest that BM and CTC samples have similar clonal structures, as discordances between the two were restricted to subclonal mutations. Accordingly, our results pave the way for potentially less invasive mutation screening of MM patients through characterization of CTCs
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