2,184 research outputs found

    Identificación de marcadores específicos de tumor en sangre para la detección precoz del cáncer de pulmón, esófago y cabeza y cuello

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    [ES] Los cánceres de pulmón, esófago y cabeza y cuello se encuentran entre aquellos que presentan una mayor incidencia mundial, siendo el cáncer de pulmón el más frecuentemente diagnosticado. En la mayoría de casos, la detección de estos tipos de cáncer ocurre en etapas avanzadas, cuando ya no es posible extirpar el tumor mediante cirugía. Al comparar tumores no diseminados con metastásicos, el gran descenso que se observa en la tasa de supervivencia a 5 años evidencia la importancia de la detección precoz para la reducción del número de muertes causadas por cáncer. En los últimos años, las numerosas ventajas que ofrece la biopsia líquida en comparación con la biopsia tisular (es mínimamente invasiva, conlleva un bajo riesgo, etc.) han despertado un gran interés por esta técnica en el diagnóstico de pacientes con cáncer. En esta línea se han desarrollado análisis de sangre multianalito que permiten determinar mutaciones driver en el ADN tumoral circulante (ctDNA) o marcadores de superficie específicos en células tumorales circulantes (CTCs). El objetivo principal del presente estudio es la elaboración y posterior validación bibliográfica de un panel de genes que se encuentren sobreexpresados en células tumorales de cuatro tipos de cáncer específico (adenocarcinoma de pulmón, cáncer de pulmón de célula escamosa, cáncer de cabeza y cuello de célula escamosa y cáncer de esófago), con el fin de desarrollar un test que permita la identificación precoz de CTCs en muestras de sangre de pacientes con cáncer, consiguiendo así un método de diagnóstico temprano y específico del tipo de cáncer en cuestión. Para la obtención del panel de genes se analizaron datos de expresión provenientes de distintas bases de datos genéticas, entre las que destaca GEPIA, aplicando como criterio prioritario para la selección de cada gen una alta expresión en células del cáncer de interés y una mínima expresión tanto en células de tejido sano como en células tumorales de un cáncer distinto al de interés. Después, se llevó a cabo una amplia búsqueda bibliográfica para recopilar información que avalara la idoneidad de los genes candidatos. Por último, se llevó a cabo el diseño de primers para la amplificación de los genes seleccionados, en vistas a realizar una validación futura de los mismos en diferentes líneas celulares tumorales. El panel de genes propuesto se dividió en 5 subgrupos. El primero contiene 12 genes y se basa en que la expresión combinada de los mismos en CTCs permita la detección de cualquiera de los cuatro tipos de cáncer evaluados. Siguiendo este mismo planteamiento, el objetivo del resto de subgrupos es la identificación temprana de un solo tipo específico de cáncer. Así, se seleccionaron 5 genes para la detección del adenocarcinoma de pulmón y 4 para la del cáncer de pulmón de célula escamosa. Por otro lado, para diagnosticar el cáncer de cabeza y cuello de célula escamosa la combinación de 6 genes demostró ser muy prometedora, mientras que solo 4 genes fueron seleccionados para el diagnóstico del cáncer de esófago. Los resultados presentados en este estudio confirman que la combinación de diferentes marcadores es esencial a la hora de obtener un test que permita la detección precoz de un tipo específico de cáncer a partir de muestras de sangre. Sin embargo, con el fin de corroborar de manera experimental la idoneidad del panel de genes propuesto sería necesario realizar futuros estudios que confirmen los datos de expresión de los genes seleccionados en muestras de tumor sólido y CTCs procedentes de pacientes.[EN] Lung, oesophageal and head and neck cancer are the first, seventh and sixth most frequently diagnosed cancers worldwide, respectively. In most cases, diagnosis of these cancers occurs at advanced stages, when surgical resection is no longer possible. The sharp decrease in the 5-year survival rate observed when comparing non-metastatic cases with widespread tumours highlights that early detection is a key factor in reducing the number of cancer-related deaths. In recent years, the numerous advantages of liquid biopsy compared to tissue biopsy (the former being minimally invasive and low risk) have generated a great level of interest regarding the use of this technique to diagnose cancer. As a result, the development of multi-analyte blood tests has made it possible to identify driver mutations in circulating tumour DNA (ctDNA) or specific surface markers in circulating tumour cells (CTCs), among others. According to this, the main objective of the present study is the development and subsequent bibliographic validation of a multigene panel comprised of genes that are overexpressed in tumour cells of four specific cancer types (lung adenocarcinoma, lung squamous cell carcinoma, head and neck squamous cell carcinoma and oesophageal carcinoma) in order to develop a test that allows early identification of CTCs in blood samples obtained from cancer patients, thereby facilitating an early diagnostic method specific for these cancers. To generate the aforementioned multigene panel, expression data obtained from different cancer genetic databases (among which GEPIA stands out) was analysed. The main criteria for gene selection were high expression of the candidate gene in specific cancer cells and minimum expression not only in normal cells, but also in tumour cells from different cancers. Then, an extensive bibliographic search was conducted to gather relevant information regarding the suitability of the candidate genes. Last of all, primers for amplification of the selected genes were designed, with a short-term goal to validate them in cancer cell lines. The proposed multigene panel was divided in 5 different subgroups. The first contains 12 genes whose combined expression in CTCs could allow for detection of any of the four cancer types assessed in this study. Following the same approach, the aim of the rest of subgroups is to allow identification of just one specific cancer type. In the case of lung cancer, 5 genes were chosen for lung adenocarcinoma and 4 genes for lung squamous cell carcinoma detection. For head and neck squamous cell carcinoma diagnosis, the combination of 6 different genes was found to be very promising, whilst only 4 genes were identified as promising candidates for diagnosis of oesophageal carcinoma. The results presented in this study confirm that a combination of different markers is essential in order to obtain a successful multiparameter blood test that allows early detection of a specific cancer type. Further studies confirming gene expression data in solid tumour samples and cancer patients¿ CTCs would be required so that the suitability of the developed multigene panel for early cancer diagnosis is experimentally corroborated.Mota Pino, J. (2020). Identificación de marcadores específicos de tumor en sangre para la detección precoz del cáncer de pulmón, esófago y cabeza y cuello. http://hdl.handle.net/10251/149514TFG

    Theoretical parameters of trailing vortices versus aspect ratio of wing models

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    We perform 2D-PIV measurements to characterize trailing vortices in NACA0012 wing models for aspect ratios ranging between 1 and 2.5, and for chord-based Reynolds numbers from 7000 to 40000. Firstly, and regarding the influence of the Reynolds number, the increase of this dimensionless parameter generates a more concentrated and intense vortex, presenting, therefore, an increase in all its characteristic magnitudes: maximum azimuthal velocity and vorticity. Secondly, the greater the aspect ratio, the greater the vortex strength is observed. Thirdly, the radial location of the peak of the azimuthal velocity has a strong decay as the aspect ratio increases for Re=7000, but it changes its trend for Re=40000.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech.. Ministerio de Economía y Competitividad (Spain) Grant No. DPI2013-40479-P and DPI2016-76151-C2-1-R and Junta de Andalucía Grant No. P11-TEP-7776

    Stability analysis of flow structures in hovering using robotic experiments and flow visualizations

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    We investigate the kinematics and stability of hovering flight making use of a robotic experimental device that simulate the movement of insects or birds. We carried out this analysis based on the characterization of this movement with flow visualizations and particle image velocimetry -PIV-. First, we characterized the kinematics of the robotic device inside water. Therefore, it has been verified that the robotic experiments follow the desired input signal precisely. Second, we give qualitative and quantitative information from the experimental tests as a function of frequency and angular amplitude. The kinematics of the hovering flight produces vortices that are stable or unstable around the rigid flat plate, as well as one transient regime that has been also found between these two latter states. Finally, dimensional velocity field plus associated vorticity have been characterized in these flow regimes through PIV measurements, and we also validated the reproducibility of experiment finding excellent agreement between different set of experiments.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tec

    PIV measurements of the effect of pulsed blowing jet on a NACA0012 wing model

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    Wingtip vortices are present in taking off, and landing operations and their presence in airport runways must be reduced. To that end, several strategies have been considered in the last decades, being the active control one possible technical solution. To compute the effectiveness of active control that corresponds to pulsed low-blowing-ratio transverse jet for the reduction of the wingtip vortex strength, we carry out 2D-PIV measurements in a towing tank for chord-based Reynolds numbers 15000 and 20000. We consider two cases: (i) no active control Rjet=0 and (ii) pulsating radial jet of blowing-ratio Rjet smaller than 1.7 (or momentum coefficient lower than 0.12) and different Strouhal numbers ranging from 0.27 to 0.94. Our observations show that the best reduction of wingtip vortex strength takes place at the lowest Strouhal number tested. We use the maximum azimuthal velocity and vorticity together with the circulation to quantify this decrease in the vortex strength. Besides, we define the spatial evolution of a disturbance parameter which allow us to detect again the optimal frequency that leads to vortex destruction.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

    Impact of the atmospheric contamination on the content of heavy metals of water leaf (Talinum triangulare) harvested in urban and peri-urban farmlands

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    The contents of cadmium, copper, manganese, nickel and lead were determined in water leaf (Talinum triangulare (Jacq.) Willd.) in different urban and peri-urban farmlands from Havana, which were previously classified according to the qualitative contamination of the air with the objective to evaluate the influence of air quality on the concentration of these metals in the plant. Determinations of these metals were made by atomic absorption spectrometry using sonication with 1 mol·L–1 nitric acid during 1 hour to take the sample to aqueous phase. Values obtained ranged from 0,1 to 0,13 ppm for cadmium; 0,89 – 1,39 ppm for copper; 18,25 – 30,41 ppm for manganese; 0,73 – 1,49 ppm for nickel and 0,52 – 0,7 ppm for lead. The Principal Component Analysis (PCA) of the results showed that the grouping of samples according to their heavy metals content followed a pattern similar to that of the classification of farmlands as to air pollution, used as criterion to conduct the study and thus PCAcan be considered as an estimator of the atmospheric ontamination by heavy metals of crops for further works

    Advances in the knowledge of vertebrate paleontology in Panama

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    J. Pino. 2012. Advances in the knowledge of vertebrate paleontology in Panama. Boletín electrónico del PCP-PIRE. Florida Museum of Natural History. https://www.floridamuseum.ufl.edu/panama-pire/voices/2012-issues/advances-in-the-knowledge-of-vertebrate-paleontology-in-panama/The first symposium on Panama’s paleontology “Advances in the understanding of vertebrate paleontology in Panama: Interchanges and Neotropical connections” was held August 16-18 at the Smithsonian Tropical Research Institute and the University of Panama. Several topics were discussed related to geology and the vertebrate fossil discoveries made in Panama, focusing on the ones made from the Panama Canal area. The knowledge produced in recent years by PCP-PIRE project researchers was also discussed. Students and faculty from the Biology department at the University of Panama and Marine Biology students at the International Maritime University of Panama attended the symposium.PIRE-PCP Project -Florida Museum of Natural History at University of Florid

    First report on the density of the small-earned shrew, cryptotis nigrescens (Eulipotypla: soricidae) from Western Panama.

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    The potential effects of climate change on the community assemblage of tropical montane species have increased the interest in understanding these species' current ecology from several perspectives. Nonetheless, the inconspicuousness of some species may have promoted that groups of small mammals, such as shrews, have escaped the general interest of local researchers in Mesoamerica. Here field-based approximations are presented for the density of the Small-eared shrew (Cryptotis nigrescens) in Panama. Shrews were collected in a grid system using Sherman live traps at the Parque Internacional La Amistad, a locality that offers a scenario for developing studies of interspecific interactions between C. nigrescens and other small mammals. A maximum density of 19 individuals per hectare was registered in a single day, and an average of 5.3 individuals per hectare based on the days with effective captures; suggesting that C. nigrescens is common in the study area. It is considered imperative to study the ecology of this shrew, which is restricted to the fragile montane environments, before they disappear

    Observaciones sobre la abundancia de los primates de La Llana Área de Conservación Alto Chagres, Panamá

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    Pino, J.L. 2007. Observaciones sobre la abundancia de los primates de La Llana: Área de Conservación Alto Chagres. Pp. 26-42 en: Informe de las actividades de censos de mamíferos en transectos con énfasis en el indicador disponibilidad de presas del jaguar en el Área de Conservación Alto Chagres, Panamá (J.L. Pino, editor). Sociedad Mastozoológica de Panamá. Documento Técnico 56p. DOI: 10.13140/RG.2.2.11821.1584
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