1,817 research outputs found

    Alternative method for the metrological characterization of spur gears in the sub-millimeter range using optical equipment

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    The aim of this work is to develop a software that allows the inspection of spur gear manufactured in the sub-millimeter range. The measurements are made using a digital optical machine and using an analysis proprietary software implemented in Matlab®, which is able to handle images, captured using the digital optical machine. The software allows to evaluate the profile and pitch deviations as establish in the ISO/TR 10064-1:1992 standar

    A proposal for the metrological characterization of circular features with digital optical machines

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    This paper aims to analyze the different adjustment methods commonly used to characterize indirect metrology circular features: least square circle, minimum zone circle, maximum inscribed circle and minimum circumscribed circle. The analysis was performed from images obtained by digital optical machines. The calculation algorithms, self-developed, have been implemented in Matlab® and take into consideration as study variables: the amplitude of angular sector of the circular feature, its nominal radio and the magnification used by the optical machine. Under different conditions, it was determined the radius and circularity error of different circular standards. The comparison of the results, obtained by the different methods of adjustments used, with certified values for the standards, has allowed us to determine the accuracy of each method and its scope

    Nuevas estrategias terapéuticas en diabetes mellitus tipo 1

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    El principal determinante del riesgo de complicaciones derivadas de la diabetes mellitus tipo 1 se debe a los altos niveles de glucosa en sangre mantenidos durante largo tiempo. Para conseguir un beneficio terapéutico en pacientes con diabetes mellitus es necesario desarrollar tratamientos que permitan de manera segura, efectiva y estable mantener la normoglucemia. Lamentablemente, el tratamiento de la diabetes mellitus tipo 1 mediante el aporte exógeno de insulina no es capaz de conseguir niveles estables de glucosa en sangre, de manera que con frecuencia se producen casos de severa hipoglucemia o hiperglucemia. Hasta la fecha la única solución para reestablecer de manera permanente la normoglucemia se consigue mediante el trasplante de páncreas o de islotes pancreáticos. Sin embargo, a medida que se incrementa el número de centros especializados en el trasplante de islotes, mayor es la necesidad de islotes para su trasplante. Así pues, el estudio de nuevas fuentes de células productoras de insulina así como de nuevos tratamientos que permitan preservar o incluso aumentar la masa de células beta en los pacientes con diabetes mellitus representa un objetivo de primera necesidad en este campo. En este sentido, en la última década ha habido un avance significativo en el campo de la biología de las células madre. Sin embargo, la identificación de células apropiadas para la generación de nuevas células beta, además del desarrollo de técnicas para la caracterización de estas células, así como de ensayos y modelos animales apropiados para probar su capacidad de diferenciación tanto in vitro como in vivo son de vital importancia para la puesta en marcha de nuevas estrategias terapéuticas basadas en la aplicación de las células madre para el tratamiento de la diabetes mellitus tipo 1

    Monitoring the phenolic ripening of red grapes using a multisensor system based on metal-oxide nanoparticles

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    Producción CientíficaThe maturity of grapes is usually monitored by means of the sugar concentration. However, the assessment of other parameters such as the phenolic content is also important because the phenolic maturity has an important impact on the organoleptic characteristics of wines. In this work, voltammetric sensors able to detect phenols in red grapes have been developed. They are based on metal oxide nanoparticles (CeO2, NiO, and TiO2,) whose excellent electrocatalytic properties toward phenols allows obtaining sensors with detection limits in the range of 10−8 M and coefficients of variation lower than 7%. An electronic tongue constructed using a combination of the nanoparticle-based sensors is capable to monitor the phenolic maturity of red grapes from véraison to maturity. Principal Component Analysis (PCA) can be successfully used to discriminate samples according to the ripeness. Regression models performed using Partial Least Squares (PLS-1) have established good correlations between voltammetric data obtained with the electrochemical sensors and the Total Polyphenolic Index, the Brix degree and the Total Acidity, with correlation coefficients close to 1 and low number of latent variables. An advantage of this system is that the electronic tongue can be used for the simultaneous assessment of these three parameters which are the main factors used to monitor the maturity of grapes. Thus the electronic tongue based on metal oxide nanoparticles can be a valuable tool to monitor ripeness. These results demonstrate the exciting possible applications of metal oxide nanoparticles in the field of electronic tongues.Ministerio de Economía, Industria y Competitividad - Fondo Europeo de Desarrollo Regional (project AGL2015-67482- R)Junta de Castilla y Leon - Fondo Europeo de Desarrollo Regional (project VA011U16)Junta de Castilla y León (grant BOCYL-D-24112015-9

    In vitro and in vivo comparative study of chimeric liver-specific promoters

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    Targeting therapeutic genes to the liver is essential to improve gene therapy protocols of hepatic diseases and of some hereditary disorders. Transcriptional targeting can be achieved using liver-specific promoters. In this study we have made chimeric constructs combining promoter and enhancer regions of the albumin, alpha 1-antitrypsin, hepatitis B virus core protein, and hemopexin genes. Tissue specificity, activity, and length of gene expression driven from these chimeric regulatory sequences have been analyzed in cultured cells from hepatic and nonhepatic origin as well as in mice livers and other organs. We have identified a collection of liver-specific promoters whose activities range from twofold to less than 1% of the CMV promoter in human hepatoma cells. We found that the best liver specificity was attained when both enhancer and promoter sequences of hepatic genes were combined. In vivo studies were performed to analyze promoter function during a period of 50 days after gene transfer to the mouse liver. We found that among the various chimeric constructs tested in this work, the alpha1-antitrypsin promoter alone or linked to the albumin or hepatitis B enhancers is the most potent in directing stable gene expression in liver cells

    Pancreatic cancer escape variants that evade immunogene therapy through loss of sensitivity to IFNgamma-induced apoptosis

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    Combined injections into experimental tumor nodules of adenovirus encoding IL-12 and certain chemokines are capable to induce immune-mediated complete regressions. In this study, we found that the combination of two adenoviruses, one encoding IL-12 and other MIP3alpha (AdCMVIL-12+AdCMVMIP3alpha) was very successful in treating CT-26-derived colon carcinomas. However, in experimental tumors generated from the pancreatic carcinoma cell line Panc02 such combined treatment induces 50% of macroscopic complete regressions, although local relapses within 1 week are almost constant. We derived cell lines from such relapsing tumors and found that experimental malignancies derived from their inoculum were not amenable to treatment in any case with AdCMVIL-12+AdCMVMIP-3alpha. Importantly, relapsing cell lines were insensitive to in vitro induction of apoptosis by IFNgamma, in clear contrast with the original Panc02 cells. Comparative analyses by cDNA arrays of relapsing cell lines versus wild-type Panc02 were performed revealing an important number of genes (383) whose expression levels were modified more than two-fold. These changes grouped in certain gene ontology categories should harbor the mechanistic explanations of the acquired selective resistance to IFNgamma

    Gene therapy of orthotopic hepatocellular carcinoma in rats using adenovirus coding for interleukin 12

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    The use of gene therapy to enhance antitumor immunity has emerged as a promising procedure to fight cancer. In this study we have tested the ability of an adenovirus carrying interleukin 12 (IL-12) gene (AdCMVIL-12) to eliminate tumoral lesions in 3 animal models of orthotopic hepatocellular carcinoma (HCC). Intratumoral injection of AdCMVIL-12 in animals with a single big tumor nodule implanted in the liver resulted in significant inhibition of tumor growth in a dose-dependent manner. Fifty percent of animals that received a dose of 5 x 10(9) plaque-forming units, showed complete regression of the tumor 2 weeks after treatment. In animals with 2 independent tumor nodules in the left liver lobe, injection in only one of them of 5 x 10(9) pfu AdCMVIL-12 induced, 15 days after therapy, complete regression of 50% of treated tumors and also of 50% of untreated lesions, with 60% long-term survival. Rats that were tumor free after therapy with AdCMVIL-12 showed protection against tumor rechallenge. A group of rats received the carcinogen diethylnitrosamine and developed multiple hepatic dysplasic nodules of 1 to 5 mm in diameter. These animals were treated by intrahepatic artery injection of either AdCMVIL-12 (5 x 10(9) pfu) or control vector. In this model AdCMVIL-12 induced complete tumor regression in 20% of treated rats and inhibited tumor growth in 60% of cases with an increase in rat survival. Activation of natural killer (NK) cells and inhibition of angiogenesis were found to be antitumor mechanisms set in motion by AdCMVIL-12. Our data indicate that experimental HCC can be efficiently treated by intratumoral or intravascular injection of adenovirus expressing IL-12

    Evaluation of a 30-gene paclitaxel, fluorouracil, doxorubicin and cyclophosphamide chemotherapy response predictor in a multicenter randomized trial in breast cancer

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    PurposeWe examined in a prospective, randomized, international clinical trial the performance of a previously defined 30-gene predictor (DLDA-30) of pathologic complete response (pCR) to preoperative weekly paclitaxel and fluorouracil, doxorubicin, cyclophosphamide (T/FAC) chemotherapy, and assessed if DLDA-30 also predicts increased sensitivity to FAC-only chemotherapy. We compared the pCR rates after T/FAC versus FAC×6 preoperative chemotherapy. We also performed an exploratory analysis to identify novel candidate genes that differentially predict response in the two treatment arms.Experimental Design273 patients were randomly assigned to receive either weekly paclitaxel × 12 followed by FAC × 4 (T/FAC, n=138), or FAC × 6 (n=135) neoadjuvant chemotherapy. All patients underwent a pretreatment FNA biopsy of the tumor for gene expression profiling and treatment response prediction.ResultsThe pCR rates were 19% and 9% in the T/FAC and FAC arms, respectively (p<0.05). In the T/FAC arm, the positive predictive value (PPV) of the genomic predictor was 38% (95%CI:21–56%), the negative predictive value (NPV) 88% (CI:77–95%) and the AUC 0.711. In the FAC arm, the PPV was 9% (CI:1–29%) and the AUC 0.584. This suggests that the genomic predictor may have regimen-specificity. Its performance was similar to a clinical variable-based predictor nomogram.ConclusionsGene expression profiling for prospective response prediction was feasible in this international trial. The 30-gene predictor can identify patients with greater than average sensitivity to T/FAC chemotherapy. However, it captured molecular equivalents of clinical phenotype. Next generation predictive markers will need to be developed separately for different molecular subsets of breast cancers

    Toshiba GCS

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    El presente trabajo es un recabado de la experiencia del alumno Miguel González cursando el proyecto de aplicación profesional dentro de la empresa de Toshiba, dentro de este documento se verán las tareas que realizó, el proyecto del cual formó parte y las responsabilidades que traía la participación de este. Se verá expresado como a lo largo del curso fueron necesarias llevar a cabo diferentes tareas de aprendizaje donde no solamente se vea beneficiado la experiencia profesional, sino también se verá un crecimiento personal dentro del ámbito personal, humano y estudiantil. Las tareas y actividades que fueron realizadas durante este lapso del tiempo serán registradas para poder tener una mejor visualización de la evolución del alumno durante la estadía de becario. Estas tareas y actividades incluyen las de autoaprendizaje, entrega de productos y comunicación integrantes del equipo. Dado que este es el segundo periodo de becario se verá en aumento la cantidad de responsabilidades y tareas relacionadas con el proyecto, dichas responsabilidades pueden requerir investigación previa. Será presentado dentro de un plan de actividades y estudios relacionado con todos los requisitos para el correcto desarrollo del plan becario, dicho plan será planteado y explicado dentro de este documento. Cada apartado dentro del plan contendrá explicado el área que se trabajará y como se trabajará, así como con que actividad y proyecto estén relacionados. Al mismo tiempo será presentado el plan de comunicación que se utilizará para mandar mensajes y mandar entregables con el resto de los integrantes del equipo, dicho equipo será presentados junto con su rol dentro del proyecto. Para la correcta documentación de este proyecto se explicará el proyecto asignado, así como las tareas que conllevó. Además de esto se hará mención del equipo y el personal con el cual se realizó cada una de las tareas.ITESO, A.C

    Toshiba GCS

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    El presente trabajo es un recabado de la experiencia del alumno Miguel González cursando el proyecto de aplicación profesional dentro de la empresa de Toshiba, dentro de este documento se verán las tareas que realizó, el proyecto del cual formó parte y las responsabilidades que traía la participación del mismo. Se verá expresado como a lo largo del curso fueron necesarias llevar a cabo tareas de aprendizaje donde no solamente se vea beneficiado la experiencia profesional, sino también se verá un crecimiento personal dentro del ámbito personal, humano y estudiantil. Las tareas y actividades que fueron realizadas durante este lapso del tiempo serán registradas para poder tener una mejor visualización de la evolución del alumno durante la estadía de becario. Estas tareas y actividades incluyen las de autoaprendizaje, entrega de productos y comunicación integrantes del equipo.ITESO, A.C
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