61 research outputs found

    Supramolecular Assembly of Edge Functionalized Top‐Down Chiral Graphene Quantum Dots

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    The construction of supramolecular assemblies of heterogeneous materials at the nanoscale is an open challenge in science. Herein, new chiral graphene quantum dots (GQDs) prepared by amidation reaction introducing chiral amide groups and pyrene moieties into the periphery of GQDs are described. The analytical and spectroscopic data show an efficient chemical functionalization and the morphological study of the supramolecular ensembles using SEM and AFM microscopies reveals the presence of highly ordered fibers of several micrometers length. Fluorescence studies, using emission spectroscopy and confocal microscopy, reveal that the fibers stem from the π-π stacking of both pyrenes and GQDs, together with the hydrogen bonding interactions of the amide groups. Circular dichroism analysis supports the chiral nature of the supramolecular aggregates

    Association of maternal body composition and diet on breast milk hormones and neonatal growth during the first month of lactation

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    Introduction: Preterm birth is associated with altered growth patterns and an increased risk of cardiometabolic diseases, with breast milk (BM) being a counteracting factor. Preterm infants also show alterations in adipokines and gut hormones influencing appetite and metabolism. Since these hormones are present in BM, it is possible that their levels may equilibrate deficiencies improving infant growth. We aimed to assess 1) the BM levels of ghrelin, resistin, leptin, insulin, peptide YY, and the gastrointestinal peptide in women with preterm and term labor; 2) the relationship between BM hormones and neonatal growth; and 3) the influence of maternal body composition and diet on these BM hormones. Methods: BM from 48 women (30 term and 18 preterm labor) was collected at days 7, 14, and 28 of lactation. Maternal body composition was evaluated by bioimpedance, and neonate anthropometric parameters were collected from medical records. The maternal dietary pattern was assessed by a 72-h dietary recall at days 7 and 28 of lactation. BM hormones were analyzed by the U-Plex Ultra-sensitive method. Data were analyzed using linear regression models. BM from women with preterm labor had lower ghrelin levels, with the other hormones being significantly higher compared to women with term delivery. Results: In premature infants, growth was positively associated with BM ghrelin, while, in term infants, it was positively associated with insulin and negatively with peptide YY. In the first week of lactation, women with preterm labor had higher body fat compared to women with term labor. In this group, ghrelin levels were positively associated with maternal body fat and with fiber and protein intake. In women with term labor, no associations between anthropometric parameters and BM hormones were found, and fiber intake was negatively associated with peptide YY. Discussion: Preterm labor is a factor influencing the levels of BM adipokines and gut hormones, with BM ghrelin being a relevant hormone for premature infant growth. Since ghrelin is lower in BM from women with preterm labor and the levels are associated with maternal fat storage and some dietary components, our data support the importance to monitor diet and body composition in women who gave birth prematurely to improve the BM hormonal statusThis research was funded by Promotion of Knowledge Transfer program (PTC-2020) from Universidad Autónoma de Madrid in collaboration with Alter Farmacia, SA, Spanish Ministry of Science, and Innovation (RTI2018-097504-B-I00

    Highly functionalized 2-oxopiperazine-based peptidomimetics: An approach to PAR1 antagonists

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    A series of pseudodipeptide-based chiral 1,3,4,5-tetrasubstituted-2- oxopiperazines has been designed and synthesized as potential PAR1 antagonists. These highly functionalized piperazines were synthesized from aromatic and basic amino acid derived Ψ[CH(CN)NH]pseudodipeptides through a four step pathway that involves reduction of the cyano group to build the 2-oxopiperazine ring, followed by selective functionalization at the N4-, N 1-positions, and at the exocyclic moiety at position C5. This regioselective functionalization required the fine tuning of reaction conditions. All new compounds were screened as inhibitors of human platelet aggregation induced by the PAR1 agonist SFLLRN and as cytotoxic agents in human cancer cell lines. Some of the compounds displayed moderate PAR1 antagonist activity, while, others were cytotoxic at μM concentration. No correlation was observed between both types of activities.Peer Reviewe

    Síndrome de Eagle. Consideraciones en Anestesiología y para el tratamiento de la vía aérea

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    El síndrome de Eagle consiste en una osificación del ligamento estilohioideo que en ocasiones se manifiesta por dolor en el cuello, disfagia o molestias inespecíficas en dicha región. En algunos casos se precisa el tratamiento quirúrgico de dicha lesión. Debido a su localización y a la osificación, cuando se realiza anestesia general con intubación traqueal pueden presentarse dificultades en el tratamiento de la vía aérea, especialmente en la intubación traqueal. Presentamos el caso de una paciente con síndrome de Eagle que iba a ser intervenida para resección de la osificación. Se discute la valoración y el tratamiento de la vía aérea.Eagle syndrome consists in a ossification of the stylohioid ligament. Sometimes clinical symptoms due to this ossification develops, consisting in neck pain, dysphagia and other. In some instances surgical treatment is needed. In this cases, if general anaesthesia should be induced, difficulties in the management of the airway including tracheal intubation should be expected. We present a female patient scheduled for surgical resection of the ossified ligament. Evaluation and clinical management of the airway is discused.Medicin

    Charge transfer-assisted self-limited decyanation reaction of TCNQ-type electron acceptors on Cu(100)

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    TCNQ derivatives adsorbed on a metal surface undergo a self-limited decyanation reaction that only affects two out of the four cyano groups in the molecule. Combined Scanning Tunneling Microscopy/X-ray Photoelectron Spectroscopy experiments and Density Functional Theory calculations relate the self-limiting behavior to the transfer of electrons from the metal to the moleculeWe thank the CCC-UAM and the RES for allocation of computer time. Our work has been supported by the MINECO of Spain (MAT2009-13488, FIS2010-18847, FIS2010-15127, FIS2012-33011, CTQ2010-17006, CTQ2011-24652/BTQ), Comunidad de Madrid (Nanobiomagnet S2009/MAT-1726, Madrisolar-2 S2009/PPQ-1533), CONSOLIDER-INGENIO on Molecular Nanoscience (CSD2007- 00010) and European Union (SMALL PITN-GA-2009-23884

    Association of maternal body composition and diet on breast milk hormones and neonatal growth during the first month of lactation

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    Preterm birth is associated with altered growth patterns and an increased risk of cardiometabolic diseases, with breast milk (BM) being a counteracting factor. Preterm infants also show alterations in adipokines and gut hormones influencing appetite and metabolism. Since these hormones are present in BM, it is possible that their levels may equilibrate deficiencies improving infant growth. We aimed to assess 1) the BM levels of ghrelin, resistin, leptin, insulin, peptide YY, and the gastrointestinal peptide in women with preterm and term labor; 2) the relationship between BM hormones and neonatal growth; and 3) the influence of maternal body composition and diet on these BM hormone

    Clinical experience with the integrase inhibitors Dolutegravir and Elvitegravir in HIV-infected patients: efficacy, safety and tolerance

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    [Abstract] Two integrase inhibitors (INSTIs), dolutegravir (DTG) and elvitegravir/cobicistat (EVG/COBI), have joined recently the pharmacotherapy arsenal against HIV. This study evaluated the efficacy and tolerability of these INSTIs in the last two years. A retrospective observational study in patients who started DTG or EVG/COBI from January 2015 to January 2017 at a reference hospital in north-western Spain was done. Epidemiological, clinical and immunovirological data were recorded. A statistical analysis was performed with SPSS software. A total of 542 DTG (n = 275)- or EVG/COBI (n = 267)-based therapies were initiated during the study period. Overall, more than 90% of naïve and pre-treated patients had virological suppression in both groups after 48 weeks of initiation of treatment per-protocol snapshot analysis. During follow-up, 10.2% of patients were treated with DTG and 4.5% of those treated with EVG discontinued due to adverse events (AE). In the case of DTG mainly related to neuropsychiatric disturbances (70.4%) and for EVG/COBI with gastrointestinal discomfort (50%). Female sex [HR 2.255 (95%CI 1.121–4.535), p = 0.023] and DTG treatment [HR 2.453 (95%CI 1.221–4.931), p = 0.012] were associated with AE discontinuations. Specifically for neuropsychiatric events, DTG treatment [HR 5.906 (95%CI 1.954–17.846), p = 0.002] and receiving abacavir/lamivudine/DTG [HR 4.380 (95%CI 1.348–14.233), p = 0.014] were identified as predictive risk factors for treatment discontinuations in two different multivariate analyses. A high percentage of AE discontinuations not previously described in clinical trials has been observed, especially with DTG. Female gender and DTG treatment were identified as risk factors for AE discontinuation. DTG-based therapies, especially in combination with abacavir/lamivudine, were associated with an increased risk of treatment discontinuation due to neuropsychiatric AE.Instituto de Salud Carlos III; CPII14/00014Instituto de Salud Carlos III; PI10/02166Instituto de Salud Carlos III; PI13/02266Instituto de Salud Carlos III; CM13/00328Instituto de Salud Carlos III; CM15/00233Instituto de Salud Carlos III; PI16/0215

    Single-molecule conductance of a chemically modified, {\pi}-extended tetrathiafulvalene and its charge-transfer complex with F4TCNQ

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    We describe the synthesis and single molecule electrical transport properties of a molecular wire containing a π{\pi}-extended tetrathiafulvalene (exTTF) group and its charge-transfer complex with F4TCNQ. We form single molecule junctions using the in-situ break junction technique using a home-built scanning tunneling microscope with a range of conductance between 10 G0_{0} down to 107^{-7} G0_{0}. Within this range we do not observe a clear conductance signature of the neutral parent molecule, suggesting either that its conductance is too low or that it does not form stable junctions. Conversely, we do find a clear conductance signature in the experiments carried out on the charge-transfer complex. Due to the fact we expected this species to have a higher conductance than the neutral molecule, we believe this supports the idea that the conductance of the neutral molecule is very low, below our measurement sensitivity. This is further supported by our theoretical calculations. To the best of our knowledge, these are the first reported single molecule conductance measurements on a molecular charge-transfer species

    Metabolic clustering analysis as a strategy for compound selection in the drug discovery pipeline for leishmaniasis

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    A lack of viable hits, increasing resistance, and limited knowledge on mode of action is hindering drug discovery for many diseases. To optimize prioritization and accelerate the discovery process, a strategy to cluster compounds based on more than chemical structure is required. We show the power of metabolomics in comparing effects on metabolism of 28 different candidate treatments for Leishmaniasis (25 from the GSK Leishmania box, two analogues of Leishmania box series, and amphotericin B as a gold standard treatment), tested in the axenic amastigote form of Leishmania donovani. Capillary electrophoresis–mass spectrometry was applied to identify the metabolic profile of Leishmania donovani, and principal components analysis was used to cluster compounds on potential mode of action, offering a medium throughput screening approach in drug selection/prioritization. The comprehensive and sensitive nature of the data has also made detailed effects of each compound obtainable, providing a resource to assist in further mechanistic studies and prioritization of these compounds for the development of new antileishmanial drugs
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