Osteogenic effects of simvastatin-loaded mesoporous titania thin films

The use of statins in the field of bone regeneration is under current investigation due to the existing demand for non-toxic anabolic agents capable of enhancing bone formation in cases of substantial loss. Simvastatin, a coenzyme currently prescribed in clinics to inhibit cholesterol biosynthesis, has been proven to promote osteogenic differentiation by stimulating bone formation and inhibiting osteoclasts activity. We present the loading of simvastatin in mesoporous TiO2 thin films toward combining the pro-osteogenic properties of this molecule with the demonstrated bioactivity of titania. TiO2 thin films processing and characterization were carried out, as well as evaluation of MC3T3-E1 pre-osteoblasts viability when directly incubated with different concentrations of simvastatin, followed by the analysis of osteogenic activity promoted by simvastatin upon loading in the thin films. The accessible porosity of 36% quantified on the 95 ± 5 nm thick mesoporous thin films, together with pore diameters of 5.5 nm, necks between pores of 2.8 nm and interpore distances of 12 ± 2 nm allow the loading of the simvastatin molecule, as confirmed by FTIR spectroscopy. Simvastatin was found to promote MC3T3-E1 pre-osteoblasts viability at concentrations ≤0.01 g l−1, with a cytotoxicity threshold of 0.05 g l−1. We additionally found that film loadings with 0.001 g l−1 simvastatin promotes statistically higher MC3T3-E1 pre-osteoblast proliferation whereas a higher concentration of 0.01 g l−1 leads to statistically higher osteogenic activity (ALP synthesis), after 21 days of incubation, as compared to unloaded films. These results demonstrate the potential of simvastatin local administration based on bioactive mesoporous thin films to promote pro-osteogenic properties. By focusing this strategy on the coating of metallic prostheses, the supply of simvastatin to the target tissue can be favored and risks of systemic side effects will be reduced while enhancing the osteointegration of the implants.Fil: Lopez Alvarez, Miriam. Universidad de Vigo; EspañaFil: López Puente, Vanesa. Universidad de Vigo; EspañaFil: Rodriguez Valencia, Cosme. Universidad de Vigo; EspañaFil: Angelome, Paula Cecilia. Comisión Nacional de Energía Atómica. Centro Atómico Constituyentes; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Liz Marzan, Luis M. Ikerbasque; EspañaFil: Serra, Julia. Universidad de Vigo; EspañaFil: Pastoriza Santos, Isabel. Universidad de Vigo; EspañaFil: Gonzalez, Pio. Universidad de Vigo; Españ

Using Surface Enhanced Raman Scattering to Analyze the Interactions of Protein Receptors with Bacterial Quorum Sensing Modulators

Many members of the LuxR family of quorum sensing (QS) transcriptional activators, including LasR of Pseudomonas aeruginosa, are believed to require appropriate acyl-homoserine lactone (acyl-HSL) ligands to fold into an active conformation. The failure to purify ligand-free LuxR homologues in nonaggregated form at the high concentrations required for their structural characterization has limited the understanding of the mechanisms by which QS receptors are activated. Surface-enhanced Raman scattering (SERS) is a vibrational spectroscopy technique that can be applied to study proteins at extremely low concentrations in their active state. The high sensitivity of SERS has allowed us to detect molecular interactions between the ligand-binding domain of LasR (LasRLBD) as a soluble apoprotein and modulators of P. aeruginosa QS. We found that QS activators and inhibitors produce differential SERS fingerprints in LasRLBD, and in combination with molecular docking analysis provide insight into the relevant interaction mechanism. This study reveals signal-specific structural changes in LasR upon ligand binding, thereby confirming the applicability of SERS to analyze ligand-induced conformational changes in proteinsS

Silver clusters of five atoms as highly selective antitumoral agents through irreversible oxidation of thiols

Low atomicity clusters present properties dependent on the size, due to the quantum confinement, with well-defined electronic structures and high stability. Here it is shown that Ag5 clusters catalyze the complete oxidation of sulfur to S+6. Ag5 catalytic activity increases with different oxidant species in the order O2 ≪ H2O2 < OH•. Selective oxidation of thiols on the cysteine residues of glutathione and thioredoxin is the primary mechanism human cells have to maintain redox homeostasis. Contingent upon oxidant concentration, Ag5 catalyzes the irreversible oxidation of glutathione and thioredoxin, triggering apoptosis. Modification of the intracellular environment to a more oxidized state to mimic conditions within cancer cells through the expression of an activated oncogene (HRASG12V) or through ARID1A mutation, sensitizes cells to Ag5 mediated apoptosis. While cancers evolve to evade treatments designed to target pathways or genetic mutations that drive them, they cannot evade a treatment that takes advantage of aberrant redox homeostasis, which is essential for tumor progression and metastasis. Ag5 has antitumor activity in mice with orthotopic lung tumors reducing primary tumor size, and the burden of affected lymphatic nodes. The findings suggest the unique intracellular redox chemistry of Ag5 may lead to new redox-based approaches to cancer therapyThis research was partially supported by 1) “la Caixa” Foundation, Ref. LCF/PR/PR12/11070003 to F.D. and M.A.L.Q.; 2) Ministerio de Ciencia, Innovación y Universidades (MAT2017-89678-R, AEI/FEDER, UE) to F.D. and A.V.; 3) the Consellería de Educación (Xunta de Galicia), Grants No. Grupos Ref. Comp. ED431C 2017/22, ED431C 2019/13 and AEMAT-ED431E2018/08 to M.A.L.Q.; and ED431C 2019/13 to A.V. This project has received funding from the European Union's Horizon 2020 Research and Innovation Programme (Bac-To-Fuel) under Grant Agreement No. 825999 (M.A.L.Q.). J.C.H. acknowledge financial support from European Union's Horizon 2020 research and innovation programme under grant agreement no. 823717-ESTEEM3, and the MICIIN (projects PID2019-107578GA-100 and PID-110018GA-100). J.M.D, L.J.G., and F.G.R. thank to the ANPCyT (PICT 2015-2285 and 2017-3944), UNLP (Project 11/X790) and the partial support by the Laboratório Nacional de Luz Síncrotron (LNLS, Brazil) under proposal SXS-20180280. G.B. acknowledges the CINECA Award N. IsC51, year 2017, under the ISCRA initiative, for the availability of high-performance computing resources and support. D.B. expresses gratitude for a postdoctoral grant from Xunta de Galicia, Spain (POS-A/2013/018). B.D. expresses gratitude for a predoctoral grant from MICINN, Spain (BES-2016-076765). F.D. and A.V. also acknowledged Xunta de Galicia (Centro singular de investigación de Galicia accreditation 2019-2022 ref ED431G 2019/02) and the European Union (European Regional Development Fund – ERDF). Work in M.P.M.'s lab was supported by the Medical Research Council UK (MC_U105663142). T.G.C. gratefully acknowledges the technical assistance of María José Otero-Fraga (FIDIS)S

Plasmonic Mesoporous Composites as Molecular Sieves for SERS Detection

Application of surface-enhanced Raman scattering (SERS) spectroscopy to the ultrasensitive analysis of small molecules in biological samples is complicated by signal contamination by ubiquitous macromolecules such as proteins, nucleic acids, or lipids. We present a proof-of-concept study of the application of composite films comprising branched gold nanoparticles embedded in mesoporous thin films, which act as molecular sieves. The inorganic mesoporous layer only allows the diffusion of small molecules toward the plasmonic particles while preventing the contact of macromolecules in solution with the optical sensor.Fil: López-Puente, Vanesa. Universidad de Vigo; EspañaFil: Abalde-Cela, Sara. Universidad de Vigo; EspañaFil: Angelome, Paula Cecilia. Comisión Nacional de Energía Atómica. Gerencia del Área de Seguridad Nuclear y Ambiente. Gerencia de Química (CAC); ArgentinaFil: Álvarez Puebla, Ramón. Universitat Rovira I Virgili; España. Centro de Tecnología Química de Cataluña; España. Institució Catalana de Recerca i Estudis Avancats (ICREA); EspañaFil: Liz-Marzán, Luis M.. Universidad de Vigo; España. Bionanoplasmonics Laboratory; Españ

Selective SERS Sensing Modulated by Functionalized Mesoporous Films

A hybrid material comprising metal nanoparticles embedded in functionalized mesoporous thin films was constructed, and its use as a selective SERS-based sensor was demonstrated. The presence of specific functional groups in the pore network allows control over the surface chemistry of the pores, tuning the selectivity for specific molecules. Amino-functionalized hybrid mesoporous thin films were used in a proof of concept experiment, to discern the presence of methylene blue (MB) in mixtures with acid blue (AB), with no need for any sample pretreatment step. Selective detection of MB was possible through entrapment of AB in the mesoporous matrix, based on its high affinity for amino groups. The sensor selectivity can be tuned by varying the solution pH, rendering a pH responsive surface and thus, selective SERS-based sensing. The developed sensors allow specific detection of molecules in complex matrixes.Fil: López Puente, Vanesa. Universidad de Vigo; EspañaFil: Angelome, Paula Cecilia. Universidad de Vigo; España. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Comisión Nacional de Energía Atómica. Centro Atómico Constituyentes; ArgentinaFil: Soler Illia, Galo Juan de Avila Arturo. Comisión Nacional de Energía Atómica. Centro Atómico Constituyentes; Argentina. Universidad Nacional de San Martin. Instituto de Nanosistemas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Liz-Marzán, Luis M.. Cic Biomagune; España. Universidad de Vigo; España. Basque Foundation For Science; España. Comisión Nacional de Energía Atómica. Centro Atómico Constituyentes; Argentin

Enhanced electrochemical sensing of polyphenols by oxygen-mediated surface

We report a straightforward heat treatment in air of commercial screen-printed carbon electrodes (SPCE) at different temperatures and times (ht-SPCE) that produces considerable electrocatalytic effects. The active area and the presence of oxygen groups on the ht-SPCE surface increased upon thermal treatment, more than doubling and by 20%, respectively. The increase of oxygen-containing carbon surface groups results in strong interactions and substantial improvement in Faradaic currents, up to a 10 fold increase in the voltammetric response of relevant polyphenols (hydroquinone, catechol, pyrogallol and dopamine). Moreover, ht-SPCE displayed higher selectivity towards the oxidation of polyphenol mixtures than the untreated SPCE. Finally, good linear ranges were obtained by voltammetric determination of dopamine with detection and quantification limits 5 times lower than the values obtained for the untreated SPCE. The versatility of oxidation by air makes this activation procedure very attractive and easy to implement, which can be further used for numerous applications in the (bio)sensor field.Xunta de Galicia/FEDER (GPC2013-006 and R2014/030), MINECO (CTQ 2010-16390, MAT2013-45168-R, CTQ2011-28157 and PRIAIBPT- 2011-1096) and by FCT/CRUP (Est-C/QUI/UI0686/2011; FCOMP-01-0124-FEDER-022716 and E-136/2012

New archaeological investigations in the ravines of Antofagasta de la Sierra (Catamarca): the case of Paicuqui

En este trabajo presentamos los primeros resultados de las tareas de investigación iniciadas recientemente en la localidad de Paicuqui (Antofagasta de la Sierra, Catamarca, Puna Meridional), con el objetivo de establecer de manera preliminar la secuencia histórica relativa de ocupación de esta localidad, a la vez que comparar la misma con la información que se tiene de otras quebradas de la microrregión. Si bien la mayor parte de los trabajos fueron prospectivos, el registro obtenido resultó significativo en cuanto al volumen y variedad de datos que reflejan diversas situaciones contextuales y una perspectiva temporal amplia desde aproximadamente 5.000 años atrás hasta tiempos históricos (coloniales y, posiblemente, republicanos). Mostramos, entonces, un análisis preliminar de las evidencias recuperadas en Paicuqui, sus contextos y su articulación con la arqueología de otros sectores de Antofagasta de la Sierra, con el fin de realizar nuevos aportes sobre diversas problemáticas vinculadas con la interacción social, la producción y circulación de bienes, cosmovisión, espacios ritualizados y prácticas asociadas.In this paper we present the first results obtained from the research tasks recently initiated in Paicuqui (Antofagasta de la Sierra, province of Catamarca, Southern Puna), with the objective of establishing, at least preliminarily, the relative historic occupational se - quence of this locality, comparing it with the information registered in other ravines of this micro-region. While the activities where mainly focused in surface surveys, the obtained register is significant regarding the volume and variety of data reflecting diverse contextual situa - tions and a wide temporal perspective encompassing from 5.000 years ago until historical moments (colonial and, possibly, republican). Thus, we expose a prelimi - nary analysis of the evidences recovered in Paicuqui, their contexts, and its articulation with the archaeology of other sectors in Antofagasta de la Sierra, with the purpose of generating new contributions regarding issues related with social interaction, production and circulation of goods, worldview, ritualized spaces, and associated practicesFil: Cohen, Maria Lorena. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Estudios Sociales. Universidad Nacional de Tucumán. Instituto Superior de Estudios Sociales; ArgentinaFil: Martel, Alvaro Rodrigo. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo. Instituto de Arqueología y Museo; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Estudios Sociales. Universidad Nacional de Tucumán. Instituto Superior de Estudios Sociales; ArgentinaFil: Ponce, Natalia Agustina. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo. Instituto de Arqueología y Museo; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Estudios Sociales. Universidad Nacional de Tucumán. Instituto Superior de Estudios Sociales; ArgentinaFil: Martinez, Maria Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Estudios Sociales. Universidad Nacional de Tucumán. Instituto Superior de Estudios Sociales; ArgentinaFil: Lepori, Matiías. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Estudios Sociales. Universidad Nacional de Tucumán. Instituto Superior de Estudios Sociales; ArgentinaFil: Zamora, Diego. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo. Instituto de Arqueología y Museo; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Estudios Sociales. Universidad Nacional de Tucumán. Instituto Superior de Estudios Sociales; ArgentinaFil: Urquiza, Silvana Valeria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Estudios Sociales. Universidad Nacional de Tucumán. Instituto Superior de Estudios Sociales; ArgentinaFil: Juarez, Vanesa Beatriz. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo. Instituto de Arqueología y Museo; Argentina. Universidad Nacional de Jujuy. Instituto de Ecorregiones Andinas. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Ecorregiones Andinas; ArgentinaFil: Elías, Alejandra. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo. Instituto de Arqueología y Museo; ArgentinaFil: González Baroni, Lucia Guadalupe. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Estudios Sociales. Universidad Nacional de Tucumán. Instituto Superior de Estudios Sociales; ArgentinaFil: Desimone, Paula Mariela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Estudios Sociales. Universidad Nacional de Tucumán. Instituto Superior de Estudios Sociales; ArgentinaFil: Puente, Verónica. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo. Instituto de Arqueología y Museo; ArgentinaFil: Porto López, José Manuel. Universidad de Buenos Aires; ArgentinaFil: Marcos, Maria Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Estudios Sociales. Universidad Nacional de Tucumán. Instituto Superior de Estudios Sociales; Argentin

El libro xilográfico

El grabado xilográfico es el elemento común de los 27 libros de artista realizados por estudiantes de la Facultad de Bellas Artes. Nos presentan libros únicos, de los que existe un solo ejemplar, encuadernados por los propios creadores y estampados en su totalidad con técnicas de impresión en madera y linóleo