8 research outputs found

    Toxic effects of methoxychlor on the episodic prolactin secretory pattern: Possible mediated effects of nitric oxide production

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    BACKGROUND: This work addresses the issue of whether methoxychlor (MTX) exposure may modify the ultradian secretion of prolactin through changes in the synthesis of nitric oxide (NO) induced by N(ω)-nitro-L-arginine methyl ester (L-NAME) in the hypothalamic-pituitary axis. Associated changes in dopamine (DA) content in the anterior (AH), mediobasal (MBH) and posterior hypothalamus (PH) and median eminence (ME) were evaluated. METHODS: Two groups of animals (MTX and MTX+L-NAME treated) received subcutaneous (sc) injections of MTX at a dose of 25 mg/kg/day for one month. The other two groups of animals (control and L-NAME treated) received sc vehicle injections (0.5 mL/day of sesame oil), during the same period of time to be used as controls. Forty hours before the day of the experiment, animals were anaesthetized with intrapritoneal injections of 2.5% tribromoethanol in saline and atrial cannulas were implanted through the external jugular vein. Plasma was continuously extracted in Hamilton syringes coupled to a peristaltic bomb in tubes containing phosphate-gelatine buffer (to increase viscosity). The plasma was obtained by decantation and kept every 7 minutes for the measurement of plasma prolactin levels through a specific radioimmnunoassay and DA concentration by high-pressure liquid chromatography (HPLC). RESULTS: Prolactin release in animals from all experimental groups analyzed was episodic. Mean plasma prolactin levels during the bleeding period, and the absolute pulse amplitude were increased after MTX or N(ω)-nitro-L-arginine methyl ester (L-NAME) administration. However MTX and L-NAME did not modify any other parameter studied with the exception of relative pulse amplitude in MTX treated rats. L-NAME administration to rats treated with the pesticide reduced mean plasma prolactin levels and the absolute amplitude of prolactin peaks. Peak duration, frequency and relative amplitude of prolactin peaks were not changed in the group of rats treated with MTX plus L-NAME as compared to either control or MTX treated rats. Whereas MTX decreased DA content in the ME and increased it in the AH, its content did not change in the MBH or PH, as compared to the values found in controls. Also, L-NAME administration decreased DA content in the ME as compared to controls. However, L- NAME administration to MTX exposed rats, markedly increased DA content in the ME as compared to either MTX treated or control rats. L-NAME administration increased DA content in the AH as compared to the values found in non-treated rats. However L-NAME administration to MTX exposed rats did not modify DA content as compared to either MTX treated or control rats. L-NAME administration did not modify DA content at the MBH nor in saline treated nor in MTX treated rats. However, the values of DA in the MBH in MTX plus L-NAME treated animals were statistically decreased as compared to L-NAME treated rats. In the PH, L-NAME administration increased DA content as compared to the values found in non-treated animals. L-NAME administration to MTX exposed rats also increased DA content as compared to either MTX treated or control rats. CONCLUSION: The results suggest the existence of an interaction between MTX and L-NAME in the modulation of the ultradian prolactin secretion at the pituitary levels. The possibility of an indirect effect mediated by changes in DA content at the ME requires further examination

    Biomonitoring of Human Exposure to Prestige Oil: Effects on DNA and Endocrine Parameters

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    Since 1960, about 400 tankers spilled more than 377765 tons of oil, with the Prestige accident (Galician coast, NW Spain, November 2002) the most recent. Taking into account the consistent large number of individuals exposed to oil that exists all over the world, it seems surprising the absence in the literature of studies focused on the chronic effects of this exposure on human health. In this work we evaluated the level of DNA damage by means of comet assay, and the potential endocrine alterations (prolactin and cortisol) caused by Prestige oil exposure in a population of 180 individuals, classified in 3 groups according to the tasks performed, and 60 controls. Heavy metals in blood were determined as exposure biomarkers, obtaining significant increases of aluminum, nickel and lead in the exposed groups as compared to controls. Higher levels of genetic damage and endocrine alterations were also observed in the exposed population. DNA damage levels were influenced by age, sex, and the use of protective clothes, and prolactin concentrations by the last two factors. Surprisingly, the use of mask did not seem to protect individuals from genetic or endocrine alterations. Moreover, polymorphisms in genes encoding for the main enzymes involved in the metabolism of oil components were analyzed as susceptibility biomarkers. CYP1A1-3′UTR and EPHX1 codons 113 and 139 variant alleles were related to higher damage levels, while lower DNA damage was observed in GSTM1 and GSTT1 null individuals

    75 años como referente de la investigación agraria y medioambiental española en condiciones de clima mediterráneo [Sitio Web]

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    1 .pdf con imagen de acceso al “website”, su url y los créditos relacionados con su creación y diseño.-- Créditos: Organización, Estación Experimental de Aula Dei (EEAD-CSIC); Dirección, Jesús Val Falcón; Coordinación, Ana Álvarez-Fernandez, Jorge Álvaro-Fuentes, Ernesto Igartua; Contenido, Anunciación Abadía, Javier Abadía, Carlos Albiñana, Miguel Alfonso, Arancha Arbeloa, Raúl Arbués, Isabel Armillas, Manuel Becana, Santiago Beguería, Carmen Castañeda, Ana Castillo, José Cavero, Bruno Contreras, Azahara Díaz, Edgar García, Elena García, Juan Manuel Gascuñana, Leticia Gaspar, Yolanda Gogorcena, Juan Herrero, Victoria Lafuente, María Victoria López, Juan Antonio Marín, José Martínez, José Carlos Martínez-Giménez, Ana Pilar Mata, Manuel Matamoros, Pierre Mignard, María Ángeles Moreno, Paula Murillo, Ana Navas, Antonio Pérez, Rafael Picorel, María Pilar Vallés, Irene Villar, Inmaculada Yruela, Nery Zapata, Isabel Zarazaga; Diseño y programación: DigitalWorks (Juanjo Ascaso y Asun Dieste); Vídeo, Delegación del CSIC en Aragón (Sara Gutiérrez y Yolanda Hernáiz); Fotografía, Archivo EEAD-CSIC, Anunciación Abadía, Jorge Álvaro-Fuentes, Arancha Arbeloa, Juanjo Ascaso, Santiago Beguería, Elena García, Ernesto Igartua, Ignasi Iglesias, José Manuel Lasa, José Carlos Martínez-Giménez, Pierre Mignard, María Ángeles Moreno, Rubén Sancho, Kosana Suvocarev, María Pilar Vallés, Nery Zapata."Sitio web" de nueva creación y conmemorativo del 75 Aniversario de la EEAD-CSIC que contiene: 1) Foto esférica de su personal en activo; 2) Recopilación de sus hitos históricos más destacados, en orden cronológico; 3) Un vídeo con participación de su personal y muestra de algunas de sus instalaciones; 4) Un mapa con la distribución geográfica de los egresado del Instituto; 5) Algunas fotos, destacando las tomadas a su personal en las celebraciones del 25 y 50 Aniversarios de la EEAD-CSIC.Presentado durante la "Jornada. 75 Aniversario EEAD-CSIC (Zaragoza, Patio de la Infanta. 30 octubre 2019)".Financiación: CSIC, Vicepresidencia Adjunta de Organización y Cultura Científica.N

    Effect of cadmium on lymphocyte subsets distribution in thymus and spleen

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    This work was designed to analyze the possible dose dependent effects of cadmium on the distribution of lymphocyte subsets within the thymus and spleen. Cadmium accumulation was also evaluated in these tissues. For this purpose, adult male rats were exposed for one month to 0, 5, 10, 25, 50 or 100 ppm of cadmium chloride (CdCl2) in the drinking water. In both spleen and thymus, the B lymphocytes increased with the doses of 5 and 10 ppm of CdCl2, and decreased with the doses of 25-100 ppm. In spleen, the doses of 25 and 50 ppm decreased CD4+ cells and the doses of 5 and 10 ppm increased CD8+ cells, while the percentage of Thymus T, CD4+, CD8+ and CD4+-CD8+ cells was not modified by cadmium treatment at any dose used in this study. After cadmium exposure, the metal was accumulated in the spleen only from the dose of 50 ppm on, and in the thymus, from the dose of 10 ppm on. In conclusion, although the accumulation of the metal is higher in thymus than in spleen, the metal affected CD4+ and CD8+ lymphocytes at the spleen but not at the thymusEn este trabajo se analizan los posibles efectos inducidos por la exposición al cadmio sobre las subpoblaciones linfocitarias en bazo y timo y se evalúa la acumulación del metal en estos tejidos. Para ello, se tratan ratas macho adultas durante un mes con cloruro de cadmio (CdCl2) en el agua de bebida a dosis de 0, 5, 10, 25, 50 y 100 ppm. En las ratas tratadas con 5 y 10 ppm de CdCl2, el porcentaje de linfocitos B aumenta en bazo y timo, descendiendo a partir de la dosis de 25 ppm, en ambos tejidos. En bazo de ratas expuestas a las dosis de 25 y 50 ppm, el porcentaje de linfocitos CD4+ desciende, mientras que a las dosis de 5 y 10 ppm, aumenta el porcentaje de células CD8+. Tras la exposición al cadmio, el porcentaje de linfocitos T, CD4+, CD8+ y CD4+-CD8+ no varía en el timo con ninguna de las dosis administradas en este estudio. En las ratas tratadas, el cadmio se acumula en el bazo a partir de la dosis de 50 ppm, mientras que en el timo, lo hace a partir de la dosis de 10 ppm. Estos resultados indican, por tanto, que aunque la acumulación de cadmio es mayor en timo que en bazo, este metal afecta a la proporción de linfocitos CD4+ y CD8+ en el bazo pero no en el tim

    Causes of human impact to protected vertebrate wildlife parallel long-term socio-economical changes in Spain

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    Obtaining information on the way human activities impact protected wildlife is not an easy task. Here, we analyze the news published by knowledgeable naturalists in Spain's most prestigious and oldest magazine devoted to the study and conservation of nature, during a 28-year period (1982-2009). We studied the logarithm of the ratio of news published annually on direct (poaching, trapping and poisoning) versus indirect impacts (road casualties, electrocutions and collisions with infrastructure), and it turned out to be negative, strong (5% annual decrease) and statistically significant, suggesting an exponential decrease of the ratio. The decreasing trend was stronger (λ=9%) when considering only direct impacts excluding cases of poisoning that showed an increasing trend over time, showing a more realistic idea of the decreasing impact by hunters. Our modelling clearly showed that the decreasing trend in the ratio was explained by the decreasing number of hunting licences active on a yearly basis, controlled by the increase in indirect impacts. In order to validate our results, we compared our analysis with the trend shown by vertebrate admissions to a major rescue centre in eastern Spain from 1994 to 2011. The results of this second analysis showed a trend with a similar inversion of causes of impact but of a stronger magnitude (λ=15%). We discuss our findings within the context of a rapidly changing economy, evolving from a rural structure to an industrialized one, and provide some applied conservation recommendations. Indirect impacts caused by infrastructure should be approached, correcting technical problems, particularly black spots where mortality cases concentrate. Direct impacts, notably the rise in the rate of poisoning cases, need to be handled, managing the causes of increase of generalist predators, such as habitat structure, promoting the return of top predators and removing sources of subsidy, better than only fighting poaching by force. © 2012 The Zoological Society of London.A.M.A. was supported by project ref. CGL2009-08298 from the Spanish Ministry of Science and Innovation, and an Isidro Parga-Pondal postdoctoral contract from Xunta de Galicia. Funds were partially provided by the Regional Government of Balearic Islands and FEDER fundingPeer Reviewe

    Biodegradación de la lignocelulosa: aspectos microbiológicos, químicos y enzimáticos del ataque fúngico a la lignina

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    Wood is the main renewable material on Earth and is largely used as building material and in paper-pulp manufacturing. This review describes the composition of lignocellulosic materials, the different processes by which fungi are able to alter wood, including decay patterns caused by white, brown, and soft-rot fungi, and fungal staining of wood. The chemical, enzymatic, and molecular aspects of the fungal attack of lignin, which represents the key step in wood decay, are also discussed. Modern analytical techniques to investigate fungal degradation and modification of the lignin polymer are reviewed, as are the different oxidative enzymes (oxidoreductases) involved in lignin degradation. These include laccases, high redox potential ligninolytic peroxidases (lignin peroxidase, manganese peroxidase, and versatile peroxidase), and oxidases. Special emphasis is given to the reactions catalyzed, their synergistic action on lignin, and the structural bases for their unique catalytic properties. Broadening our knowledge of lignocellulose biodegradation processes should contribute to better control of wood-decaying fungi, as well as to the development of new biocatalysts of industrial interest based on these organisms and their enzymes.These studies have been partially supported by ENCE (Spain), by Spanish projects AGL2002-393 and BIO2002-1166, by EU projects QLK5-99-1357 and QLK3-99-590, and by an EUFORES(ENCE)-PDT/MEC(Uruguay) grant. Carmen Ascaso (CCMA, CSIC, Madrid) is acknowledged for low-temperature scanning-electron microscopy facilities. Klaus Piontek (ETH, Zurich) is acknowledged for solving the VP crystal structure. Lina Bettucci (Universidad de la República, Montevideo) is acknowledged for an Inocutis jamaicensis strain. M.S acknowledges MEC for a Postdoctoral Fellowship. F.J.R.-D. thanks CSIC for an I3P contract. A.G. and S.C. thank MEC for their “Ramón y Cajal” contracts.Peer reviewe
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