109 research outputs found
Effect of the electrode potential on the surface composition and crystal structure of LiMn2O4 in aqueous solutions
Cubic spinel LiMn2O4 has been studied for the reversible extraction of Li+ from natural brine after the application of suitable electrode potentials. In this work we report on the insertion/extraction of Li+ from natural brine of Olaroz salt flat (Jujuy, Argentina) and aqueous LiCl solutions into/from Li1-xMn2O4 (0 < x ≤ 1) to determine changes in the crystal structure and surface composition upon electrochemical polarization. In agreement with the behavior in organic electrolytes, we found that the insertion and extraction of Li+ proceeds via a two stage process and that the crystal structure undergoes two cubic phase transitions as the lattice is expanded or contracted. Contrary to the behavior in organic solvents, no decomposition layer is formed on the electrode surface and the surface composition can be controlled with the electrode potential. We also found that sodium cations present in natural brine are not inserted into the crystal lattice in the potential window explored, however they are adsorbed on the oxide surface blocking Li+ adsorption sites and decreasing the rate of Li+ exchange.Fil: Marchini, Florencia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química, Física de los Materiales, Medioambiente y Energía. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química, Física de los Materiales, Medioambiente y Energía; ArgentinaFil: Calvo, Ernesto Julio. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química, Física de los Materiales, Medioambiente y Energía. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química, Física de los Materiales, Medioambiente y Energía; ArgentinaFil: Williams, Federico José. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química, Física de los Materiales, Medioambiente y Energía. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química, Física de los Materiales, Medioambiente y Energía; Argentin
Comparative analysis of objective and subjective outcomes of two different intraocular lenses: trifocal and extended range of vision
Objective: To evaluate objective and subjective outcomes after bilateral implantation of two different multifocal intraocular lenses, which correct pseudophakic presbyopia in an adequate and homogeneous population court. Methods and analysis: Fifty patients were evaluated at 3 months after bilateral implantation, at the Eye Clinic of University of Verona and at the Carones Ophthalmology Center Milano, as follows: Tecnis Symfony (25 patients), Alcon PanOptix (25 patients). Main outcomes were uncorrected and best-corrected distance visual acuity (UDVA and BCVA) at 4 m, 60 cm (best distance corrected intermediate visual acuity (BDCIVA) and uncorrected intermediate visual acuity), 40 cm (best distance corrected near visual acuity (BDCNVA) and uncorrected near visual acuity (UNVA)), objective refractive outcome, defocus curve, contrast sensitivity (Modulation Transfer Function (MTF) cut-off), optical quality (Strehl ratio), aberrometry (root mean square RMS 4 mm), subjective quality of life (National Eye Institute Refractive Error Quality of Life score (NEI-RQL-42 score) test). Results: Symfony and PanOptix showed BCVA and UDVA comparable results. Symfony presented significant better outcomes at BDCIVA (p=0.001), while PanOptix showed better performances at BDCNVA and UNVA (p=0.01). Symfony achieved better results in RMS 4 mm (p=0.024) and in MTF cut-off (p=0.041). In the questionnaire NEI-RQL-42, PanOptix presented better scores in 'near vision' and 'spectacles independence', whereas Symfony in 'symptoms' and 'clarity of vision'. Conclusion: Both intraocular lenses are valid options to avoid pseudophakic presbyopia, even though they present different features which make them unique. Symfony allows patients to achieve a better objective and subjective quality of vision and contrast sensitivity; PanOptix provides better outcomes in near vision and spectacles independence requirements
HER2-Driven Carcinogenesis: New Mouse Models for Novel Immunotherapies
HER2 overexpression is a hallmark of aggressive breast cancer subtypes, and HER2-targeted therapies, such as passive immunotherapy with the humanized monoclonal antibody Trastuzumab, have become standard treatments for these tumor subtypes. However, increasing evidence points to a major role for the Δ16HER2 splice variant, which is commonly coexpressed with the wild-type protein, in cancer progression, metastatic potential and resistance to Trastuzumab treatment. Using our recently derived mouse strain transgenically expressing human Δ16HER2 under the transcriptional control of the MMTV promoter, we showed that this HER2 isoform per se can transform mammary epithelium in vivo. Thus, Δ16HER2 mice provide a new preclinical model in which to study mammary carcinogenesis and the metastatic process, as well as new therapies, including immune-based DNA vaccines. Such vaccines, by virtue of the polyclonal response they induce, might synergize with standard treatments and might ensure targeting of HER2 variants no longer recognized by monoclonal antibodies. In addition, immunological memory might provide long-term anticancer immune protection without side effects associated with many conventional therapies. The efficacy of DNA vaccination against the HER2 oncoantigen has been widely demonstrated in BALB-neuT mice transgenically expressing the activated rat neu oncogene and recapitulating several features of human breast cancers; however, HER2 is a self-tolerated molecule and an effective response to it must circumvent tolerance mechanisms.
Here, we retrace the findings that have led to our most promising DNA vaccines encoding human/rat chimeric forms of the HER2 molecule bearing both xenogeneic and syngeneic portions of the protein and able to overcome peripheral tolerance. Preclinical data obtained with our DNA vaccines have provided the rationale for their use in an ongoing phase I clinical trial
Diseño de experiencia en la cadena del turismo
El trabajo realizado por el Centro de Diseño Industrial en la región está detallado en un informe que se dio en llamar “Diseño de experiencia en la cadena del turismo”, el cual presenta las acciones y la metodología empleada. El documento se centra en las necesidades del turista como usuario de servicios y en las experiencias por ellos vividas. Además busca capitalizar el potencial del diseño para observar las diferentes realidades (mediante técnicas etnográficas) y detectar oportunidades, en este caso ligadas al desarrollo productivo industrial de la región. Otro aspecto relevante tiene que ver con visualizar capacidades y la posibilidad de motorizar acciones que las potencien a partir del trabajo colaborativo.
La metodología utilizada, conjuga acciones de indagación y relevamiento por diferentes medios, análisis crítico de la información tanto cuantitativa como cualitativa y la síntesis para poder sacar conclusiones y realizar propuestas que sean factibles de implementar en el territorio. Para ello se realizaron una serie de aproximaciones de manera de obtener información de diversas fuentes, de primera mano y poder procesarla de manera gráfica. En este sentido se realizaron charlas, se tomaron registros fotográficos y fílmicos, se realizaron entrevistas y reuniones con actores clave, visita a empresas o emprendimientos relacionados con la temática, se relevó la información disponible sobre el turismo y la región (en internet y en diferentes soportes), y se analizaron los diferentes tipos de usuarios o turistas. Toda esta información se encuentra procesada y reordenada en la publicación «Diseño de experiencia en la cadena del turismo».
A partir del relevamiento territorial se realizó un documento gráfico de oportunidades detectadas (que es la mencionada publicación), se elaboró una base de datos con los actores locales y experiencias, y se diseñó un mapa de recursos regional (actores, capacidades y experiencias). Por último y con la idea de dar continuidad y poder desarrollar las oportunidades detectadas se presentaron una serie de propuesta para llevar adelante en el territorio.Eje temático: Turismo cultural: experiencia y desarrollo comunitari
Tuning the electronic properties at the surface of BaBiO3 thin films
The presence of 2D electron gases at surfaces or interfaces in oxide thin films remains a hot topic in condensed matter physics. In particular, BaBiO3 appears as a very interesting system as it was theoretically proposed that its (001) surface should become metallic if a Bi-termination is achieved (Vildosola et al., PRL 110, 206805 (2013)). Here we report on the preparation by pulsed laser depositionand characterization of BaBiO3 thin films on silicon. We show that the texture of the films can be tuned by controlling the growth conditions, being possible to stabilize strongly (100)-textured films. We find significant differences on the spec- troscopic and transport properties between (100)-textured and non-textured films.We rationalize these experimental results by performing first principles calcula- tions, which indicate the existence of electron doping at the (100) surface. This stabilizes Bi ions in a 3+ state, shortens Bi-O bonds and reduces the electronic band gap, increasing the surface conductivity. Our results emphasize the importance of surface effects on the electronic properties of perovskites, and provide strategies to design novel oxide heterostructures with potential interface-related 2D electron gases. C 2016 Author(s). All article content, except where other- wise noted, is licensed under a Creative Commons Attribution (CC BY) licenseFil: Ferreyra, Cristian Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Comisión Nacional de Energía Atómica. Gerencia del Área de Investigaciones y Aplicaciones no Nucleares. Gerencia de Física (Centro Atómico Constituyentes); ArgentinaFil: Güller, Francisco. Comisión Nacional de Energía Atómica. Gerencia del Área de Investigaciones y Aplicaciones no Nucleares. Gerencia de Física (Centro Atómico Constituyentes); Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Marchini, Florencia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química, Física de los Materiales, Medioambiente y Energía. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química, Física de los Materiales, Medioambiente y Energía; ArgentinaFil: Lüders, U.. Centre National de la Recherche Scientifique; FranciaFil: Albornoz, C.. Comisión Nacional de Energía Atómica. Gerencia del Área de Investigaciones y Aplicaciones no Nucleares. Gerencia de Física (Centro Atómico Constituyentes); ArgentinaFil: Leyva, Adelma Graciela. Universidad Nacional de San Martín. Escuela de Ciencia y Tecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Comisión Nacional de Energía Atómica. Gerencia del Área de Investigaciones y Aplicaciones no Nucleares. Gerencia de Física (Centro Atómico Constituyentes); ArgentinaFil: Williams, Federico José. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química, Física de los Materiales, Medioambiente y Energía. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química, Física de los Materiales, Medioambiente y Energía; ArgentinaFil: Llois, Ana Maria. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Comisión Nacional de Energía Atómica. Gerencia del Área de Investigaciones y Aplicaciones no Nucleares. Gerencia de Física (Centro Atómico Constituyentes); ArgentinaFil: Vildosola, Veronica Laura. Comisión Nacional de Energía Atómica. Gerencia del Área de Investigaciones y Aplicaciones no Nucleares. Gerencia de Física (Centro Atómico Constituyentes); Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Rubi, Diego. Comisión Nacional de Energía Atómica. Gerencia del Área de Investigaciones y Aplicaciones no Nucleares. Gerencia de Física (Centro Atómico Constituyentes); Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de San Martín. Escuela de Ciencia y Tecnología; Argentin
Identification of Relevant Conformational Epitopes on the HER2 Oncoprotein by Using Large Fragment Phage Display (LFPD)
We developed a new phage-display based approach, the Large Fragment Phage Display (LFPD), that can be used for
mapping conformational epitopes on target molecules of immunological interest. LFPD uses a simplified and more effective
phage-display approach in which only a limited set of larger fragments (about 100 aa in length) are expressed on the phage
surface. Using the human HER2 oncoprotein as a target, we identified novel B-cell conformational epitopes. The same
homologous epitopes were also detected in rat HER2 and all corresponded to the epitopes predicted by computational
analysis (PEPITO software), showing that LFPD gives reproducible and accurate results. Interestingly, these newly identified
HER2 epitopes seem to be crucial for an effective immune response against HER2-overexpressing breast cancers and might
help discriminating between metastatic breast cancer and early breast cancer patients. Overall, the results obtained in this
study demonstrated the utility of LFPD and its potential application to the detection of conformational epitopes on many
other molecules of interest, as well as, the development of new and potentially more effective B-cell conformational
epitopes based vaccines
The Human Splice Variant Δ16HER2 Induces Rapid Tumor Onset in a Reporter Transgenic Mouse.
Several transgenic mice models solidly support the hypothesis that HER2 (ERBB2) overexpression or mutation promotes
tumorigenesis. Recently, a HER2 splice variant lacking exon-16 (D16HER2) has been detected in human breast carcinomas.
This alternative protein, a normal byproduct of HER2, has an increased transforming potency compared to wild-type (wt)
HER2 receptors. To examine the ability of D16HER2 to transform mammary epithelium in vivo and to monitor D16HER2-
driven tumorigenesis in live mice, we generated and characterized a mouse line that transgenically expresses both human
D16HER2 and firefly luciferase under the transcriptional control of the MMTV promoter. All the transgenic females
developed multifocal mammary tumors with a rapid onset and an average latency of 15.11 weeks. Immunohistochemical
analysis revealed the concurrent expression of luciferase and the human D16HER2 oncogene only in the mammary gland
and in strict correlation with tumor development. Transgenic D16HER2 expressed on the tumor cell plasma membrane from
spontaneous mammary adenocarcinomas formed constitutively active homodimers able to activate the oncogenic signal
transduction pathway mediated through Src kinase. These new transgenic animals demonstrate the ability of the human
D16HER2 isoform to transform ‘‘per se’’ mammary epithelium in vivo. The high tumor incidence as well as the short latency
strongly suggests that the D16HER2 splice variant represents the transforming form of the HER2 oncoprotein
Redox imbalance is associated to lung damage triggered by silver nanoparticles exposure
Along with the AgNP applications development, the concern about their possible toxicity has increasingly gained attention. As the respiratory system is one of the main exposure routes, the aim of this study was to evaluate the harmful effects developed in the lung after an acute AgNP exposure. In vivo studies using Balb/c mice intranasally instilled with 0.1 mg AgNP/kg b.w, were performed. 99mTc-AgNP showed the lung as the main organ of deposition, where, in turn, AgNP may exert barrier injury observed by increased protein content and total cell count in BAL samples. In vivo acute exposure showed altered lung tissue O2 consumption due to increased mitochondrial active respiration and NOX activity. Both O2 consumption processes release ROS triggering the antioxidant system as observed by the increased SOD, catalase and GPx activities and a decreased GSH/GSSG ratio. In addition, increased protein oxidation was observed after AgNP exposure. In A549 cells, exposure to 2.5 μg/mL AgNP during 1 h resulted in augment NOX activity, decreased mitochondrial ATP associated respiration and higher H2O2 production rate. Lung 3D tissue model showed AgNP-initiated barrier alterations as TEER values decreased and morphological alterations. Taken together, these results show that AgNP exposure alters O2 metabolism leading to alterations in oxygen metabolism lung toxicity. AgNP-triggered oxidative damage may be responsible for the impaired lung function observed due to alveolar epithelial injury.Fil: Garces, Mariana Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Bioquímica y Medicina Molecular. Universidad de Buenos Aires. Facultad Medicina. Instituto de Bioquímica y Medicina Molecular; ArgentinaFil: Magnani, Natalia Daniela. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Bioquímica y Medicina Molecular. Universidad de Buenos Aires. Facultad Medicina. Instituto de Bioquímica y Medicina Molecular; ArgentinaFil: Pecorelli, Alessandra. Università di Ferrara; ItaliaFil: Calabró López, María Valeria. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Bioquímica y Medicina Molecular. Universidad de Buenos Aires. Facultad Medicina. Instituto de Bioquímica y Medicina Molecular; ArgentinaFil: Marchini, Timoteo Oscar. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Bioquímica y Medicina Molecular. Universidad de Buenos Aires. Facultad Medicina. Instituto de Bioquímica y Medicina Molecular; ArgentinaFil: Caceres, Lourdes Catalina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Bioquímica y Medicina Molecular. Universidad de Buenos Aires. Facultad Medicina. Instituto de Bioquímica y Medicina Molecular; ArgentinaFil: Pambianchi, Erika. Università di Ferrara; ItaliaFil: Galdopórpora, Juan Manuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Química y Metabolismo del Fármaco. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Química y Metabolismo del Fármaco; ArgentinaFil: Vico, Tamara Antonela. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Bioquímica y Medicina Molecular. Universidad de Buenos Aires. Facultad Medicina. Instituto de Bioquímica y Medicina Molecular; ArgentinaFil: Salgueiro, María Jimena. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; ArgentinaFil: Zubillaga, Marcela Beatriz. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Moretton, Marcela Analía. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Desimone, Martín Federico. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Química y Metabolismo del Fármaco. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Química y Metabolismo del Fármaco; ArgentinaFil: Alvarez, Silvia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Bioquímica y Medicina Molecular. Universidad de Buenos Aires. Facultad Medicina. Instituto de Bioquímica y Medicina Molecular; ArgentinaFil: Valacchi, Giuseppe. Università di Ferrara; ItaliaFil: Evelson, Pablo Andrés. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Bioquímica y Medicina Molecular. Universidad de Buenos Aires. Facultad Medicina. Instituto de Bioquímica y Medicina Molecular; Argentin
Impact of trans-stent gradient on outcome after PCI: results from a HAWKEYE substudy
To test whether quantitative flow ratio (QFR)-based trans-stent gradient (TSG) is associated with adverse clinical events at follow-up. A post-hoc analysis of the multi-center HAWKEYE study was performed. Vessels post-PCI were divided into four groups (G) as follows: G1: QFR >= 0.90 TSG = 0 (n = 412, 54.8%); G2: QFR >= 0.90, TSG > 0 (n = 216, 28.7%); G3: QFR < 0.90, TSG = 0 (n = 37, 4.9%); G4: QFR < 0.90, TSG > 0 (n = 86, 11.4%). Cox proportional hazards regression model was used to analyze the effect of baseline and prognostic variables. The final reduced model was obtained by backward stepwise variable selection. Receiver operating characteristic (ROC) was plotted and area under the curve (AUC) was calculated and reported. Overall, 449 (59.8%) vessels had a TSG = 0 whereas (40.2%) had TSG > 0. Ten (2.2%) vessel-oriented composite endpoint (VOCE) occurred in vessels with TSG = 0, compared with 43 (14%) in vessels with TSG > 0 (p < 0.01). ROC analysis showed an AUC of 0.74 (95% CI: 0.67 to 0.80; p < 0.001). TSG > 0 was an independent predictor of the VOCE (HR 2.95 [95% CI 1.77-4.91]). The combination of higher TSG and lower final QFR (G4) showed the worst long-term outcome while low TSG and high QFR showed the best outcome (G1) while either high TSG or low QFR (G2, G3) showed intermediate and comparable outcomes. Higher trans-stent gradient was an independent predictor of adverse events and identified a subgroup of patients at higher risk for poor outcomes even when vessel QFR was optimal (> 0.90)
MultiPhen: Joint Model of Multiple Phenotypes Can Increase Discovery in GWAS
The genome-wide association study (GWAS) approach has discovered hundreds of genetic variants associated with diseases and quantitative traits. However, despite clinical overlap and statistical correlation between many phenotypes, GWAS are generally performed one-phenotype-at-a-time. Here we compare the performance of modelling multiple phenotypes jointly with that of the standard univariate approach. We introduce a new method and software, MultiPhen, that models multiple phenotypes simultaneously in a fast and interpretable way. By performing ordinal regression, MultiPhen tests the linear combination of phenotypes most associated with the genotypes at each SNP, and thus potentially captures effects hidden to single phenotype GWAS. We demonstrate via simulation that this approach provides a dramatic increase in power in many scenarios. There is a boost in power for variants that affect multiple phenotypes and for those that affect only one phenotype. While other multivariate methods have similar power gains, we describe several benefits of MultiPhen over these. In particular, we demonstrate that other multivariate methods that assume the genotypes are normally distributed, such as canonical correlation analysis (CCA) and MANOVA, can have highly inflated type-1 error rates when testing case-control or non-normal continuous phenotypes, while MultiPhen produces no such inflation. To test the performance of MultiPhen on real data we applied it to lipid traits in the Northern Finland Birth Cohort 1966 (NFBC1966). In these data MultiPhen discovers 21% more independent SNPs with known associations than the standard univariate GWAS approach, while applying MultiPhen in addition to the standard approach provides 37% increased discovery. The most associated linear combinations of the lipids estimated by MultiPhen at the leading SNPs accurately reflect the Friedewald Formula, suggesting that MultiPhen could be used to refine the definition of existing phenotypes or uncover novel heritable phenotypes
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