182 research outputs found
Effects of 3D nanocomposite bioceramic scaffolds on the immune response
The interaction of new nanocomposite mesoporous glass/hydroxyapatite (MGHA) scaffolds with immune cells involved in both innate and acquired immunity has been studied in vitro as an essential aspect of their biocompatibility assessment. Since the immune response can be affected by the degradation products of bioresorbable scaffolds and scaffold surface changes, both processes have been evaluated. No alterations in proliferation and viability of RAW-264.7 macrophage-like cells were detected after culture on MGHA scaffolds which did not induce cell apoptosis. However, a slight cell size decrease and an intracellular calcium content increase were observed after contact of this cell line with MGHA scaffolds or their extracts. Although no changes in the percentages of RAW cells with low and high contents of reactive oxygen species (ROS) are observed by the treatment with 7 day extracts, this study has revealed modifications of these percentages after direct contact with scaffolds and by the treatment with 24 h extracts, related to the high reactivity/bioactivity of this MGHA nanocomposite at initial times. Furthermore, when normal fresh murine spleen cells were used as an experimental model closer to physiological conditions, no significant alterations in the activation of different immune cell subpopulations were detected in the presence of 24 h MGHA extract. MGHA scaffolds did not affect either the spontaneous apoptosis or intracellular cytokine expression (IL-2, IL-10, IFN-gamma, and TNF-alpha.) after 24 h treatment. The results obtained in the present study with murine immune cell subpopulations (macrophages, lymphocytes B, lymphocytes T and natural killer cells) support the biocompatibility of the MGHA material and suggest an adequate host tissue response to their scaffolds upon their implantation
Identification of a homolog of Arabidopsis DSP4 (SEX4) in chestnut: its induction and accumulation in stem amyloplasts during winter or in response to the cold_
Oligosaccharide synthesis is an important cryoprotection strategy used by woody plants during winter dormancy. At the onset of autumn, starch stored in the stem and buds is broken down in response to the shorter days and lower temperatures resulting in the buildup of oligosaccharides. Given that the enzyme DSP4 is necessary for diurnal starch degradation in Arabidopsis leaves, this study was designed to address the role of DSP4 in this seasonal process in Castanea sativa Mill. The expression pattern of the CsDSP4 gene in cells of the chestnut stem was found to parallel starch catabolism. In this organ, DSP4 protein levels started to rise at the start of autumn and elevated levels persisted until the onset of spring. In addition, exposure of chestnut plantlets to 4 °C induced the expression of the CsDSP4 gene. In dormant trees or cold-stressed plantlets, the CsDSP4 protein was immunolocalized both in the amyloplast stroma and nucleus of stem cells, whereas in the conditions of vegetative growth, immunofluorescence was only detected in the nucleus. The studies indicate a potential role for DSP4 in starch degradation and cold acclimation following low temperature exposure during activity–dormancy transition
Synthesis of titanium and zirconium complexes with 2-pyridonate and 2, 6-pyridinedithiolate ligands
Special Issue: Dedicated to Professor F. Ekkehardt Hahn on the Occasion of His 60th Birthday with our most Sincere Congratulations for his Outstanding Contributions to Chemistry and Best Wishes.Treatment of complex [Cp2TiCl2] with the lithium salt of 2-hydroxypyridine afforded complex [Cp2Ti(Opy)2] (1), whereas the same synthetic strategy applied to the analogous zirconium compound [Cp2ZrCl2] did not worked. However, the use of the metallocene [Cptt 2ZrMe2] with protic ligands allowed directing the reactivity towards protonation of the methyl groups attached to zirconium. To check this approach we reacted [Cptt 2ZrMe2] with methanol affording complex [Cptt 2ZrMe(OMe)] (2), which was characterized in situ by NMR techniques. In the same line, the reaction of [Cptt 2ZrMe2] with 2-hydroxypyridine gave complex [Cptt 2Zr(Me)(Opy)] (3); forcing the conditions of this reaction did not lead to the expected complex [Cptt 2Zr(Opy)2], most probably due to the steric hindrance exerted by the bulky cyclopentadienyl ligands. Further reactions of complex 3 with ligands having acidic protons also led to the recovery of the starting complex. However, when shifting to the bifunctional ligand 2, 6-dimercaptopyridine [py(SH)2] a double protonation of the methyl ligands in [Cptt 2ZrMe2] occurred, allowing the isolation of mononuclear complex [Cptt 2Zr(κS,κS,κN-pyS2)] (4), upon evolution of methane. The molecular structure of complex 4 was determined by X-ray methods, showing the zirconium atom in a highly distorted trigonal bipyramidal arrangement; structural parameters indicate a conventional Zr-N bond, but rather weak Zr-S interactions.Financial support from the Spanish Ministry of Economy and Competitiveness (MINECO/FEDER, Projects CTQ2012-35665 and CTQ2013-42532-P), MICINN (Project Consolider Ingenio 2010, CSD2009-00050) and Diputación General de Aragón (DGA/ FSE-E07 and E70) is gratefully acknowledged.Peer Reviewe
Translations into English of several chapters from the book "Interpretación en contextos de violencia de género" published by the Speak Out for Support (SOS-VICS) project and supervised by Prof. Jim Hlavac from Monash University, Melbourne, Australia
Predictive Value of Serum Antibodies and Point Mutations of AQP4, AQP1 and MOG in A Cohort of Spanish Patients with Neuromyelitis Optica Spectrum Disorders
The detection of IgG aquaporin-4 antibodies in the serum of patients with Neuromyelitis optica (NMO) has dramatically improved the diagnosis of this disease and its distinction from multiple sclerosis. Recently, a group of patients have been described who have an NMO spectrum disorder (NMOsd) and who are seronegative for AQP4 antibodies but positive for IgG aquaporin-1 (AQP1) or myelin oligodendrocyte glycoprotein (MOG) antibodies. The purpose of this study was to determine whether AQP1 and MOG could be considered new biomarkers of this disease; and if point mutations in the gDNA of AQP4, AQP1 and MOG genes could be associated with the etiology of NMOsd. We evaluated the diagnostic capability of ELISA and cell-based assays (CBA), and analyzed their reliability, specificity, and sensitivity in detecting antibodies against these three proteins. The results showed that both assays can recognize these antigen proteins under appropriate conditions, but only anti-AQP4 antibodies, and not AQP1 or MOG, appears to be a clear biomarker for NMOsd. CBA is the best method for detecting these antibodies; and serum levels of AQP4 antibodies do not correlate with the progression of this disease. So far, the sequencing analysis has not revealed a genetic basis for the etiology of NMOsd, but a more extensive analysis is required before definitive conclusions can be drawn.Ministerio de Economía y CompetitividadFEDER (Grants PI16/01249 y PI16/00493
Mixed Ionic and Electronic Conducting Eutectogels for 3D-Printable Wearable Sensors and Bioelectrodes
Eutectogels are a new class of soft ion conductive materials that are attracting attention as an alternative to conventional hydrogels and costly ionic liquid gels to build wearable sensors and bioelectrodes. Herein, the first example of mixed ionic and electronic conductive eutectogels showing high adhesion, flexibility, nonvolatility, and reversible low-temperature gel transition for 3D printing manufacturing is reporting. The eutectogels consist of choline chloride/glycerol deep eutectic solvent, poly(3,4-ethylenedioxythiophene): lignin sulfonate, and gelatin as the biocompatible polymer matrix. These soft materials are flexible and stretchable, show high ionic and electronic conductivities of 7.3 and 8.7 mS cm−1, respectively, and have high adhesion energy. Due to this unique combination of properties, they could be applied as strain sensors to precisely detect physical movements. Furthermore, these soft mixed ionic electronic conductors possess excellent capacity as conformal electrodes to record epidermal physiological signals, such as electrocardiograms and electromyograms, over a long time.M.L.P. and A.G. contributed equally to this work. This work was supported by Marie Sklodowska-Curie Research and Innovation Staff Exchanges (RISE) under the grant agreement No 823989 “IONBIKE.” The financial support received from CONICET and ANPCyT (Argentina) is also gratefully acknowledged. Thanks to the Flexible Electronic Department (FEL) of Ecole des Mines de Saint-Etienne (EMSE) for the combined mechanical/electrical characterization
Contribution of the non-effector members of the HrpL regulon, iaaL and matE, to the virulence of Pseudomonas syringae pv. tomato DC3000 in tomato plants
Incluye 4 ficheros de datosBackground: The phytohormone indole-3-acetic acid (IAA) is widely distributed among plant-associated bacteria. Certain strains of the Pseudomonas syringae complex can further metabolize IAA into a less biologically active amino acid conjugate, 3-indole-acetyl-ε-L-lysine, through the action of the iaaL gene. In P. syringae and Pseudomonas savastanoi strains, the iaaL gene is found in synteny with an upstream gene, here called matE, encoding a putative MATE family transporter. In P. syringae pv. tomato (Pto) DC3000, a pathogen of tomato and Arabidopsis plants, the HrpL sigma factor controls the expression of a suite of virulence-associated genes via binding to hrp box promoters, including that of the iaaL gene. However, the significance of HrpL activation of the iaaL gene in the virulence of Pto DC3000 is still unclear.
Results: A conserved hrp box motif is found upstream of the iaaL gene in the genomes of P. syringae strains. However, although the promoter region of matE is only conserved in genomospecies 3 of this bacterial group, we showed that this gene also belongs to the Pto DC3000 HrpL regulon. We also demonstrated that the iaaL gene is transcribed both independently and as part of an operon with matE in this pathogen. Deletion of either the iaaL or the matE gene resulted in reduced fitness and virulence of Pto DC3000 in tomato plants. In addition, we used multicolor fluorescence imaging to visualize the responses of tomato plants to wild-type Pto DC3000 and to its ΔmatE and ΔiaaL mutants. Activation of secondary metabolism prior to the development of visual symptoms was observed in tomato leaves after bacterial challenges with all strains. However, the observed changes were strongest in plants challenged by the wild-type strain, indicating lower activation of secondary metabolism in plants infected with the ΔmatE or ΔiaaL mutants.
Conclusions: Our results provide new evidence for the roles of non-type III effector genes belonging to the Pto DC3000 HrpL regulon in virulence.This research was supported by the Spanish Plan Nacional I+D+i grants AGL2011-30343-CO2-01, AGL2014-53242-C2-1-R and BIO2007-67874-C02-02 as well as by grants ref. P08-CVI-03475 and P12-AGR-0370 from the Junta de Andalucía (Spain)
Aprendizaje Basado en Retos en el campo de la geotecnia: reparación de un deslizamiento de ladera
Para mejorar las competencias en el área de geotecnia de los alumnos de la ETSI de Caminos de la UPM se ha llevado a cabo un Proyecto de Innovación Educativa basado en la metodología del Aprendizaje Basado en Retos. El objetivo principal fue proporcionar a los alumnos una experiencia profesional en el campo de la ingeniería geotécnica, de tal forma que aumentase su confianza en los conocimientos adquiridos de cara a su incorporación al mundo laboral. El reto planteado fue la reparación de una rotura de talud, y el proceso seguido asemejó al que se realizaría en una empresa de ingeniería. Para facilitar la labor del alumno y mejorar la calidad de la experiencia, se organizaron, a lo largo del trabajo, reuniones con especialistas del sector. En este artículo se describe la metodología planteada, así como los resultados obtenidos. Aunque los alumnos valoraron positivamente la propuesta, no se pudo completar la actividad debido al abandono generalizado aproximadamente a la mitad de la misma. En el documento se analizan las causas de este abandono, siendo la principal de ellas la elevada carga de trabajo de los alumnos en la época final del curso
Marcas de alfareros en terra sigillata en los yacimientos en torno a Martos (Jaén). Nuevos aportes al conocimiento del territorio de la Colonia Augusta Gemella Tuccitana en época alto imperial
El área de procedencia de los materiales de nuestro estudio no forma un conjunto homogéneo, ni tiene unos límites bien definidos, ya que existen yacimientos muy distantes entre si de los que revisaremos material. A pesar de ello, es en la comarca en torno a Martas donde se ubican la mayoría de los yacimientos tratados, siendo la zona sobre la que vamos a centrar nuestra atención. Al analizar algunos yacimientos, alejados de Martos, no hemos pretendido entrar en su problemática concreta, ni en la de su territorio, sino tan sólo facilitar una serie de información y apreciaciones sobre aspectos de su cultura material, que aportan nuevos datos a la hora de hacer valoraciones más definitivas y globales sobre ellos.The analysis of terra sigillata potters' stamps found on the surface of sites surrounding Martos (Jaén) enables us to devise an assignrnent chart of the pottery with regard to its corresponding production centres, as well as to make some assesrnents on borh chronological and commercial grounds. Conclusions thereof should shed some fresh light on the domain ruled by the Colonia Augusta Gemella Tuccitana at different stages of the Early Rornan Empire
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