423 resultados para BIOTECNOLOGÍA


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Dung roller beetles of the genus Canthon (Coleoptera: Scarabaeinae) emit an odorous secretion from a pair of pygidial glands. To investigate the chemical composition of these secretions, we used stir bar sorptive extraction (SBSE), coupled with gas chromatography–mass spectrometry (GC–MS) for analysis of extracts of pygidial gland secretions secreted by the dung roller beetles Canthon femoralis femoralis and Canthon cyanellus cyanellus. Chemical analyses of volatiles collected from pygidial gland secretions comprise a great diversity of the functional groups. Chemical profile comparisons showed high intra- and interspecific variability. The pygidial gland secretion of Canthon f. femoralis was dominated by sesquiterpene hydrocarbons, whereas the profile of Canthon c. cyanellus was dominated by carboxylic acids. The different pygidial secretions have a high diversity of chemical compounds suggesting a multifunctional nature involving some key functions in the biology. We discuss the biological potential of these compounds found in the pygidial glands of each species with respect to their ecological and behavioral relevance.

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In some cases external morphology is not sufficient to discern between populations of a species, as occurs in the dung beetle Canthon humectus hidalgoensis Bates; and much less to determine phenotypic distances between them. FTIR-ATR spectroscopy show several advantages over other identification techniques (e.g. morphological, genetic, and cuticular hydrocarbons analysis) due to the non-invasive manner of the sample preparation, the relative speed of sample analysis and the low-cost of this technology. The infrared spectrum obtained is recognized to give a unique ‘fingerprint’ because vibrational spectra are specific and unique to the molecular nature of the sample. In our study, results showed that proteins, amino acids and aromatic ethers of insect exocuticle have promising discriminative power to discern between different populations of C. h. hidalgoensis. Furthermore, the correlation between geographic distances between populations and the chemical distances obtained by proteins + amino acids + aromatic ethers was statistically significant, showing that the spectral and spatial information available of the taxa together with appropriated chemometric methods may help to a better understanding of the identity, structure, dynamics and diversity of insect populations.

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The haloarchaeon Haloferax mediterranei is able to grow in the presence of different inorganic and organic nitrogen sources by means of the assimilatory pathway under aerobic conditions. In order to identify genes of potential importance in nitrogen metabolism and its regulation in the halophilic microorganism, we have analysed its global gene expression in three culture media with different nitrogen sources: (a) cells were grown stationary and exponentially in ammonium, (b) cells were grown exponentially in nitrate, and (c) cells were shifted to nitrogen starvation conditions. The main differences in the transcriptional profiles have been identified between the cultures with ammonium as nitrogen source and the cultures with nitrate or nitrogen starvation, supporting previous results which indicate the absence of ammonium as the factor responsible for the expression of genes involved in nitrate assimilation pathway. The results have also permitted the identification of transcriptional regulators and changes in metabolic pathways related to the catabolism and anabolism of amino acids or nucleotides. The microarray data was validated by real-time quantitative PCR on 4 selected genes involved in nitrogen metabolism. This work represents the first transcriptional profiles study related to nitrogen assimilation metabolism in extreme halophilic microorganisms using microarray technology.

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Background: Haloferax mediterranei is a denitrifying haloarchaeon using nitrate as a respiratory electron acceptor under anaerobic conditions in a reaction catalysed by pNarGH. Other ions such as bromate, perchlorate and chlorate can also be reduced. Methods: Hfx. mediterranei cells were grown anaerobically with nitrate as electron acceptor and chlorate reductase activity measured in whole cells and purified nitrate reductase. Results: No genes encoding (per)chlorate reductases have been detected either in the Hfx. mediterranei genome or in other haloarchaea. However, a gene encoding a chlorite dismutase that is predicted to be exported across the cytoplasmic membrane has been identified in Hfx. mediterranei genome. Cells did not grow anaerobically in presence of chlorate as the unique electron acceptor. However, cells anaerobically grown with nitrate and then transferred to chlorate-containing growth medium can grow a few generations. Chlorate reduction by the whole cells, as well as by pure pNarGH, has been characterised. No clear chlorite dismutase activity could be detected. Conclusions: Hfx. mediterranei pNarGH has its active site on the outer-face of the cytoplasmic membrane and reacts with chlorate and perchlorate. Biochemical characterisation of this enzymatic activity suggests that Hfx. mediterranei or its pure pNarGH could be of great interest for waste water treatments or to better understand biological chlorate reduction in early Earth or Martian environments. General significance: Some archaea species reduce (per)chlorate. However, results here presented as well as those recently reported by Liebensteiner and co-workers [1] suggest that complete perchlorate reduction in archaea follows different rules in terms of biological reactions.

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Chitosan permeabilizes plasma membrane and kills sensitive filamentous fungi and yeast. Membrane fluidity and cell energy determine chitosan sensitivity in fungi. A five-fold reduction of both glucose (main carbon (C) source) and nitrogen (N) increased 2-fold Neurospora crassa sensitivity to chitosan. We linked this increase with production of intracellular reactive oxygen species (ROS) and plasma membrane permeabilization. Releasing N. crassa from nutrient limitation reduced chitosan antifungal activity in spite of high ROS intracellular levels. With lactate instead of glucose, C and N limitation increased N. crassa sensitivity to chitosan further (4-fold) than what glucose did. Nutrient limitation also increased sensitivity of filamentous fungi and yeast human pathogens to chitosan. For Fusarium proliferatum, lowering 100-fold C and N content in the growth medium, increased 16-fold chitosan sensitivity. Similar results were found for Candida spp. (including fluconazole resistant strains) and Cryptococcus spp. Severe C and N limitation increased chitosan antifungal activity for all pathogens tested. Chitosan at 100 μg ml-1 was lethal for most fungal human pathogens tested but non-toxic to HEK293 and COS7 mammalian cell lines. Besides, chitosan increased 90% survival of Galleria mellonella larvae infected with C. albicans. These results are of paramount for developing chitosan as antifungal.

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Two new species of Anomala Samouelle from Costa Rica are described: Anomala moroni new species and A. parvaeucoma new species. Habitus, protibia, distribution map, and male genitalia (aedeagus and endophallus) of each species are illustrated. A key for the dorsally setose species from the Neotropical region is provided.

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The word technology refers to the knowledge of techniques, skills, methods or processes used to produce goods, services or to reach specific objectives (research, business, etc.). The concept technology can also be used to make reference to devices, computers and factories.

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Se presentan dos localidades para una especie de "Raïm de Pastor" de origen Chino-Japonés (Sedum sarmentosum Bunge), que no había sido citado expresamente en localidades valencianas. Se ha localizado exclusivamente en las localidades de Almudaina, Comarca de El Comtat (Alicante) y en el Portell de Morella, Comarca de Els Ports (Castellón). En la primera localidad se ha podido constatar la facilidad de esta planta para naturalizarse en tejados y repisas, próximos al punto de cultivo, por lo que aunque actualmente es una planta muy rara, habrá que vigilar su comportamiento futuro en las comarcas de montaña valencianas, dada su resistencia al frío y a la sequía. Por otra parte, es una especie con usos medicinales en la tradición china para problemas gástricos, renales y desórdenes hormonales, además, actualmente se está investigando activamente como antitumoral.

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Aims: To determine the prevalence of endometriosis in epithelial ovarian cancers (EOC) and the association among their histological subtypes and with endometrial carcinoma. Methods: An observational cohort study performed in 192 patients operated on for EOC, 30 women with atypical endometriosis and 17 with p53 positive endometriosis. Data on associated endometriosis and endometrial carcinomas, histological subtypes, tumor stage, clinical and pathological characteristics and survival were analyzed. Results: Twenty cases of EOC (10.4%) had also endometriosis (12.7 in borderline and 9.3% in invasive cases), being a synchronous finding in most cases. Endometriosis associated with serous or mucinous EOC was observed in 2.2 and 2.7% of cases, respectively. However, this association was observed in 50 of endometrioid and 23% of clear cell EOC. Age, parity and tumor stage were lower in endometriosis-associated EOC patients; and all associated cases were type I (Kurman and Shih's classification) and showed better results in survival rate. Endometrial carcinoma was more frequently associated with endometrioid EOC (25%). Conclusions: There is a significant association between endometriosis, including atypical forms, and endometrioid and clear cell carcinomas, but not with other EOC histotypes. The presence of endometriosis in EOC suggests a better prognosis and an intermediate stage within the progression endometriosis-carcinoma.

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INTRODUCCIÓN: La salud es un concepto básico para el mantenimiento de una población, que agrupa nociones e impresiones de un sujeto. Se trata de un conjunto de bienestar físico, social y mental condicionado por la influencia de los factores socioeconómicos y culturales. Muchas investigaciones se basaron en las mediciones subjetivas de la salud para enfocar el tema desde la perspectiva del paciente y no solo del profesional de salud. Las nociones estudiadas en la presente investigación son la calidad y estilo de vida de la población universitaria femenina, además de las impresiones que incluyen las vivencias del dolor crónico y de la imagen corporal de la misma población. También, se añadió la variable “etnia” al presente estudio por su importancia junto al género y al nivel educativo, a la hora de determinar y analizar cada uno de los conceptos mencionados. Además, se estudiaron el dolor crónico y la imagen corporal desde un punto de vista subjetivo-emocional basado en la semántica de algunas palabras que definen el significado de estos fenómenos según cada persona y población étnica. METODOLOGÍA: Se recurrió a la metodología de encuestas utilizando para ello cuatro cuestionarios para cada concepto estudiado. Las entrevistas se elaboraron en las Universidades UA y UMH de Alicante (España) y Universidad Abdelmalek Essaadi de Tetuán (Marruecos), agrupados en: 318 mujeres, entre ellas 127 mujeres españolas residentes en Alicante, 85 mujeres de nacionalidad marroquí que reside en Alicante también y 106 mujeres marroquíes residentes en Tetuán. La elección de la edad no fue una variable condicionante ya que la población universitaria se encontraba en el intervalo de 18 a 36 años que define una población generalmente joven. Esto es de interés por ser la etapa que más marca el estado de salud durante el resto de la vida. Dentro de la población universitaria, se eligió únicamente la femenina por ser la más vulnerable en las vivencias, percepciones y cambios en la imagen corporal, alimentación y dolor. Para la evaluación de la calidad de vida relacionada con la salud se empleó el cuestionario de salud SF-36 que agrupa las ocho dimensiones determinantes de la salud percibida. Los indicadores clásicos de morbilidad (presencia de procesos patológicos, consumo de medicamentos) y estilo de vida (tipo de alimentación, consumo de alcohol y tabaco, actividad física) se resumieron a partir de la Encuesta Nacional de Salud Española (ENS 2006). El estudio del dolor crónico y de la imagen corporal basándose en la semántica, se evaluó a través de un cuestionario genérico del Diferencial Semántico. Además se añadió otro aspecto para el estudio de la imagen corporal, basado en Figuras Anatómicas que determinan el Índice de Masa Corporal (IMC) percibido. RESULTADOS: Los resultados obtenidos muestran diferencias apreciables en la percepción de la calidad de vida de las mujeres marroquíes frente a las españolas, mostrando mejores puntuaciones en las españolas y peores en las marroquíes de Alicante. La prevalencia de algunas patologías fue generalmente alta en la población marroquí. Lo más destacado fueron los altos porcentajes de depresión u otros trastornos menores en las marroquíes de Alicante y la anemia en las españolas de Alicante. Los medicamentos se consumen por parte de toda la población universitaria, con altos porcentajes de analgésicos utilizados por la población marroquí residente en Alicante. Aparecen también los reconstituyentes sobre todo para la población marroquí de Alicante por ser la que peor estado de salud tiene. La alimentación seguida es inadecuada para toda la población, y necesita cambios según los coeficientes calculados del Índice de Alimentación Saludable. Las mujeres que llevan una dieta sana son escasas y pertenecen sobre todo al grupo de las universitarias españolas. En lo referido a la práctica de actividad física y consumo de tabaco, los altos porcentajes son hallados en las universitarias españolas, dos conceptos que normalmente deben aparecer en sentido inverso. Las marroquíes de Alicante practican menos actividad física comparadas con la población universitaria estudiada. El consumo de alcohol no fue un dato relevante, ya que se trata de una etnia religiosa que no consume alcohol. Los resultados obtenidos del cuestionario de dolor crónico, muestran puntuaciones bajas en toda la población universitaria con una percepción negativa, sobre todo en las marroquíes de Alicante. La imagen corporal evaluada con el Diferencial Semántico muestra una insatisfacción hacia el propio cuerpo en todas las mujeres, en especial las marroquíes residentes en Alicante. Los IMC ideales elegidos a partir de las figuras anatómicas facilitadas, muestran una diferencia marcada entre las dos etnias: las mujeres españolas eligen las figuras que presentan los IMC bajos, como figura Ideal, mientras que las marroquíes eligen modelos Ideales con más peso. CONCLUSIONES: Las universitarias españolas valoran mejor su calidad de vida en comparación a las marroquíes de Tetuán. Las marroquíes residentes en Alicante perciben una calidad de vida menor que las otras universitarias. Las mujeres participantes en este estudio muestran valores del IMC dentro de la normalidad aunque la prevalencia de sobrepeso y obesidad se encuentra alta únicamente en las universitarias marroquíes de Tetuán. En lo relativo a los estilos de vida, las diferencias observadas entre las mujeres no se basan tanto en las patologías ni en los medicamentos consumidos. Sin embargo, las universitarias españolas realizan más actividad física y llevan una alimentación generalmente saludable. El perfil nutricional es preocupante ya que todas las universitarias necesitan un cambio en el tipo de alimentación siendo las marroquíes de Alicante las que peor calidad de dieta tienen. Las vivencias del dolor crónico determinadas por el Diferencial Semántico mostraron una percepción negativa, para todas la universitarias. Basándonos en la etnia y el lugar de nacimiento, las españolas puntúan mejor este concepto frente a las marroquíes de Tetuán. Las marroquíes que viven en Alicante perciben el dolor de una manera negativa. El consumo de analgésicos no mostró rendimientos positivos sobre este último grupo, mientras que en los otros grupos de mujeres parece que el consumo de este tipo de medicina ayuda al afrontamiento del dolor. La percepción de la imagen corporal mostró una insatisfacción por la propia imagen en todas las mujeres universitarias sin mostrar grandes diferencias entre grupos. Esta insatisfacción corporal difiere en el modelo del cuerpo elegido, ya que las españolas prefieren ser más delgadas, mientras que las marroquíes eligen tener más peso para una Imagen Corporal Ideal. El ámbito universitario y la etnia y el lugar de nacimiento son condiciones, dentro de las variables sociodemográficas, que determinan el grado de variación del IMC, la calidad de vida percibida, algunos aspectos del estilo de vida, las vivencias del dolor crónico y la percepción de la imagen corporal.

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In the last two decades, the increase in the use of artificial fertilizers and the disposal of industrial wastes have been the main factors responsible for the progressive increase in nitrate and nitrite levels in groundwater and soil. A variety of analytical strategies have been developed for nitrate and nitrite detection but electrochemical biosensors, which are simple, cheap, easily miniaturized and suitability for real-time detection, are proved to be a powerful tool. Various types of biosensors based on the use of whole cells or on the immobilization of denitrification enzymes have been developed, but their use is limited in environmental analysis under extreme conditions such as brines, acidic or basic wastewaters, salted soils, etc. Extremophilic denitrifying microorganism are good candidates for the development of new nitrate and nitrite biosensors and, in particular, haloarchaeal based biosensors would have advantages over bacterial based biosensors since the microorganisms and the purified denitrifying enzymes tolerate a wide range of temperature and salinity. This work summarizes new highlights on the potential uses of denitrifying haloarchaeal enzymes to make enzyme-based biosensors.

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The knowledge of the distributional patterns of saproxylic beetles is essential for conservation biology due to the relevance of this fauna in the maintenance of ecological processes and the endangerment of species. The complex community of saproxylic beetles is shaped by different assemblages that are composed of species linked by the microhabitats they use. We evaluate how different the species distribution patterns that are obtained can be, depending on the analyzed assemblage and to what extent these can affect conservation decisions. Beetles were sampled using hollow emergence and window traps in three protected areas of the Iberian Peninsula. Species richness, composition, and diversity turnover were analyzed for each sampling method and showed high variation depending on the analyzed assemblage. Beta diversity was clearly higher among forests for the assemblage captured using window traps. This method collects flying insects from different tree microhabitats and its captures are influenced by the forest structuring. Within forests, the assemblages captured by hollow emergence traps, which collect the fauna linked to tree hollows, showed the largest turnover of species, as they are influenced by the characteristics of each cavity. Moreover, the selection of the forest showing the highest species richness strongly depended on the studied assemblage. This study demonstrates that differences in the studied assemblages (group of species co-occurring in the same habitat) can also lead to significant differences in the identified patterns of species distribution and diversity turnover. This fact will be necessary to take into consideration when making decisions about conservation and management.

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This review refers to the Silphium (Apiaceae), one of the most enigmatic plants in the history of the Mediterranean. In Greco-Roman world, it was a panacea and especially, a powerful aphrodisiac which left many written historical references, in addition to their image mosaics and coins. Silphium extinction, due to over-exploitation is certainly a good example for the conservation of biodiversity and for the defense of sustainable use of natural resources.

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The sex determination is an event of great relevance in the life cycle of those plants that reproduce sexually. In recent years we have obtained substantial advances in elucidating the mechanisms involved, and in particular the role of epigenetic factors, in plant sex determination. Taking into account the relevance of this topic especially for dioecious species threatened as Cycads studies have been underwent to determine the basis of epigenetics of sex and to test whether compounds such as the de-metilating agent 5-azacytidine may be involved in sexual expression. This paper reviews the main progress made within this context obtained in Z. furfuraceae as well as cases of reversal of sex in cycads and different plant species.