Microarrays de DNA en el cáncer oral

Uno de los principales objetivos en la investigación sobre el cáncer en la actualidad es el estudio de marcadores que puedan predecir el pronóstico o la respuesta al tratamiento de forma individual. El número de genes implicados en los distintos pasos de la carcinogénesis oral aumenta a medida que se investiga sobre el tema. Los microarrays de DNA permiten el análisis simultáneo de la expresión de cientos de genes de un tejido en un solo experimento. El formato paralelo del ensayo permite el estudio de diferencias en la expresión genética entre células normales y enfermas, puesto que la actividad de cada gen en el microarray puede ser comparada en dos poblaciones celulares distintas. El objetivo de este trabajo es hacer una breve revisión de los estudios realizados por diversos autores que han intentado identificar genes relacionados con el cáncer oral, así como clasificarlo en subgrupos según los patrones de expresión genética; lo que permitirá una precoz detección, mejor diagnóstico y pronóstico del cáncer oral.One of the principal aims of modern cancer research is to identify markers allowing individual prediction of prognosis or response to treatment. In this connection, the number of genes thought to be involved in the different stages of different types of oral cancer increases apace. DNA microarrays allow simultaneous evaluation of the expression of hundreds of genes in a single assay. The parallel format of microassay slides is designed to allow rapid comparison of gene expression between two samples, for example tumor cells and healthy cells. This article reviews studies that have aimed to identify genes related to oral cancer, and to classify these genes into groups that are commonly co-expressed. These studies suggest that DNA microarrays are set to become routine tools in the detection, diagnosis, characterization and treatment of oral cancers

Map-elites algorithm for features selection problem

In the High-dimensional data analysis there are several challenges in the fields of machine learning and data mining. Typically, feature selection is considered as a combinatorial optimization problem which seeks to remove irrelevant and redundant data by reducing computation time and improve learning measures. Given the complexity of this problem, we propose a novel Map-Elites based Algorithm that determines the minimum set of features maximizing learning accuracy simultaneously. Experimental results, on several data based from real scenarios, show the effectiveness of the proposed algorithm.CONACYT – Consejo Nacional de Ciencia y TecnologíaPROCIENCI

Peroxidase expression in a cereal cyst nematode (Heterodera avenae) resistant hexaploid wheat line.

The incompatible interaction between plant and pathogen is often determined by the hypersensitive reaction (HR). This response is associated with accumulation of reactive oxygen species (ROS), which results in adverse growth conditions for pathogens. Two major mechanisms involving either NADPH oxidases or peroxidases have been proposed for generation of ROS. Peroxidases (PER, EC 1.11.1.7), present in all land plants, are members of a large multigenic family with high number of isoforms involved in a broad range of physiological processes. PER genes, which are expressed in nematode feeding sites, have been identified in several plant species (Zacheo et al. 1997). A strong correlation between HR and PER activities at four and seven days post nematode infection, was detected in roots of wheat lines carrying Cre2, Cre5 (from Ae. ventricosa) or Cre7 (from Ae. triuncialis) Heterodera avenae resistance genes (Andrés et al. 2001; Montes et al. 2003, 2004). We have studied changes in root of peroxidase mRNAs levels after infection by H. avenae of a wheat/Ae. ven¬tricosa introgression line (H-93-8) carrying Cre2 (Delibes et al. 1993). We also report and classify the predicted protein sequences derived from complete peroxidase transcripts

Organic matter accumulation during the Holocene in the Guadalquivir marshlands (SW Spain)

The distribution of biomarker compounds and magnetic susceptibility observed in the sediment from a 20 m core drilled in the marshlands of the estuarine region of the Guadalquivir River (southwest coast of Spain) has allowed us to reconstruct the palaeoenvironmental evolution of this area during the Holocene. Several organic compounds (n-alkanes, ra-ketones, n-alkanols, n-alkanoic acids and organic sulphur), as well as different biomarker ratios, have been used to show changing environmental conditions through time. These geochemical proxies suggest good preservation of the organic matter, although some diagenesis has occurred to particular organic compounds, especially the n-alkanoic acids. Our data indicate a major allochthonous supply of terrestrial plants, with less influence from aquatic plants or algae through the core. There are markedly different palaeoenvironmental conditions between the uppermost 5 m (last 6ka cal. B.P.) and the rest of the core. From 5 m (ca 6ka cal. B.P.) to 19 m (ca 8ka cal. B.P.) depth the palaeoenvironmental conditions were almost constant. Based on organic sulphur content and n-alkane content logs, anoxic conditions prevailed from 8 to 6ka cal. B.P., while oxic conditions with enhanced convection of water (prevalence of fluvial input), and consequently a greater organic matter supply, predominated in the upper 5 m of the core. Similarly, little variation in the magnetic susceptibility profile below 5 m indicates stable environmental conditions, while in the upper 5 m conditions shifted to one with elevated water input and clastic sediment supply. This is linked to palaeofloral alterations in the Guadiamar/Guadalquivir drainage basins and/or anthropogenic effects. We propose that from ca 8 to 6 ka cal. B.P. a stable landscape physiognomy in the surroundings of the estuarine area of the Guadalquivir River, with a predominance of pines and grassland. However, over the last 6ka cal. B.P. a variation in the terrestrial plant biomarker compounds suggests an alternation of relatively dry and humid phases and/or the impact of human populations on altering the vegetation community have occurred

Issues related to the MEDITS reference list of species

The MEDITS survey programme started in 1994 and adopted the basic protocols by the four first partners, just before the first survey. These protocols included the design of the survey, the sampling gear, the information collected, and the management of the data as far as the production of common standardized analyses of the data (Bertrand et al., 2002). The last updating of protocols has been done in 2007 (MEDITS, 2007). According to it, for each species the total weight and number of individuals is recorded. For a reference list of 38 species of fish, crustaceans and cephalopods, the length frequency by sex must be reported, as well as the maturity stage of the gonads. However, two different things should be taken into account. On one hand, for most works performed using MEDITS data (including assessments), the length frequency distributions are used, without taking into account the sex. On the other hand, the period of the surveys is not always coincident with the spawning season for all the species in the MEDITS reference list. This document attempts to be a practical exercise in relation to these topics, using both surveys and commercial data, and gives some proposals to the reference list of specie

Longitudinally extensive transverse myelitis with AQP4 antibodies revealing ovarian teratoma.

Paraneoplastic myelitis is a rare inflammatory disorder most frequently associated with solid tumors or lymphoproliferative disorders. Patients often harbor onconeuronal antibodies and their prognosis is usually poor. Here we report a 42-year old woman with longitudinally extensive transverse myelitis and aquaporin-4 (AQP4) antibodies that led to the diagnosis of ovarian teratoma. After tumor removal and immune therapy (including corticosteroids, plasma exchange, intravenous immunoglobulins and rituximab) the patient progressively improved achieving complete recovery. Histological study of the teratoma demonstrated neural tissue containing AQP4 expressing cells and intense inflammatory infiltrates, providing evidence for a possible paraneoplastic link between both disorders

Spatial and temporal variability of discards indicators and fishery factors affecting otter-trawl fishery in the spanish Mediterranean sea

A set of diversity indices were studied from data of observers on board two Mediterranean trawlers from 2001 to 2009. These diversity indices comprise relationships between total catch, landing and discard fractions to explore the accuracy of the estimates and to analyse the series trends using different methods, such as ARIMA. The hypothesis tested was that diversity indicators give a good representation of the changes produced in impacted bottom‐trawl areas, providing a reasonable fit of the data. ARIMA models are useful because they handle time-correlated modelling and forecasting. These techniques can also reveal changes in total catch as well changes in catch composition, probably induced by changes in effort fishery, seasonal (time) fluctuations, and environmental or climatic processes. Contrasted trends were also compared with survey data by MEDITS Mediterranean trawl survey time‐series indicator

Representación paramétrica de la transformada de Fourier de tejidos textiles

The periodic nature of textile fabric images allows the use of fast Fourier transformation techniques for classification. Due to the repetition patterns within the images of the textile fabric, it is possible to find a relatively easy way of description for their spectral energy density. A previously published work allows to show the use of descriptors for the Fourier spectrum of the images, in particular their efficiency to the invariance to the rotation, translation and change of scale [1].La naturaleza periódica de las imágenes de tejido textil permite el uso de las técnicas de la transformación de Fourier rápida para su clasificación. Debido a los patrones de repetición dentro de las imágenes del tejido textil, es posible encontrar una forma relativamente fácil de descripción para su densidad espectral de energía. Un trabajo previamente publicado permite mostrar el uso de descriptores para el espectro de Fourier de las imágenes, en particular su eficiencia a la invarianza a la rotación, traslación y cambio de escala [1]

Representación paramétrica de la transformada de Fourier de tejidos téxtiles

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Representación paramétrica de la transformada de Fourier de tejidos textiles

The periodic nature of the fabric images allows using fast Fourier transform techniques in image processing for its characterization. Due to the repetition of patterns inside the images of textile, is possible to find a form relatively easy of description in their energy spectrum. A recent work outlines a group of geometric descriptors for the Fourier spectrum of the images; looking for this efficiency to rotation, translation and scale change invariance [1]. These descriptors showed to be very effective to represent a textile fabric and can be used to characterize the quasi periodic textures in real time and in situ non destructive techniques. Samples of textile textures are tested to this technique of parametric representation with the purpose of analyzing their robustness and reproducibility. Finally, a set of textile fabrics is subjected to this model with the aim of evaluating the possibilities to carry out classification, verification and pattern recognition.PACS: 42.30.KqLa naturaleza periódica de las imágenes de tejido textil permite el uso de las técnicas de la transformación de Fourier rápida para su clasificación. Debido a los patrones de repetición dentro de las imágenes del tejido textil, es posible encontrar una forma relativamente fácil de descripción para su densidad espectral de energía. Un trabajo previamente publicado permite mostrar el uso de descriptores para el espectro de Fourier de las imágenes, en particular su eficiencia a la invarianza a la rotación, traslación y cambio de escala [1].Dichos descriptores mostraron ser muy efectivos para representar un tejido textil y pueden ser utilizados para caracterizar texturas cuasi¿periódicas mediante técnicas no destructivas en tiempo real e in situ. Muestras de texturas textiles son evaluadas con esta técnica de representación paramétrica con el propósito de analizar su robustez y reproducibilidad. Finalmente, un conjunto de tejidos textiles es sometido a este modelo con el objetivo de evaluar la posibilidad de utilizarlo para la clasificación, verificación y reconocimiento de formas.PACS: 42.30.K