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1.
Laeonereis acuta was seasonally collected in an industrially polluted site (P) and in an unpolluted site (UP) at the Patos Lagoon estuary (southern Brazil). Glutathione S-transferase (GST), superoxide dismutase (SOD) and catalase (CAT) activity (U/mg protein) was determined in five groups of worms from each site. Metallothionein (MT - mol GSH/g ww) and lipid peroxides content (LPO - nmoles of cumene hydroperoxide/g ww) were also measured. Annual mean values for CAT (UP=3.7+/-0.3; P=5.7+/-0.6), GST (UP=0.034+/-0.003; P=0.045+/-0.004) and MT (UP=0.15+/-0.02; P=0.23+/-0.03) were higher (p<0.05) in worms from the P site. In autumn, CAT activity was higher (p<0.05) in worms from the P site (7.6 +/- 1.3) than in those from the UP site (3.6 +/- 0.4). In summer, MT concentration was higher in worms from the P site (0.37 +/- 0.03) than in those from the UP site (0.19 +/- 0.01). No significant difference (p>0.05) in the LPO content was observed in worms from the different sites or collected in different seasons. These results indicate that worms from the polluted site showed higher antioxidant responses than those from the unpolluted site, sufficient to prevent oxidative damage in terms of LPO. 相似文献
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Geracitano LA Bocchetti R Monserrat JM Regoli F Bianchini A 《Marine environmental research》2004,58(1):1-17
Acute (4 days) and chronic (14 days) effects of copper were evaluated on the antioxidant defenses of Laeonereis acuta (Polychaeta) collected in unpolluted (UP) and polluted (P) sites. In the acute assay (125 and 250 micro g Cu/l) superoxide dismutase (SOD) and glutathione S-transferase (GST) activities did not change, whereas catalase (CAT) increased in worms from both the sites. Lipid peroxidation was higher in copper exposed worms from the P site. In the chronic assay (62.5 micro g Cu/l) polychaetes from the P site showed enhanced activities of SOD, GST and CAT and higher contents of metallothionein-like proteins and sulfhydrils compared to worms from UP. Differences in responses between polychaetes from UP and P sites suggest that organisms from the polluted site, P, are more susceptible to oxidative stress conditions. 相似文献
3.
M. Galindo M. Vece M. Perondi M. Monserrat Aráoz G. García M. del V. Hidalgo M. Apella M. Blesa 《Environmental Geology》2001,40(7):847-852
Major ionic composition and other chemical parameters were determined at five sampling stations on the Salí River (Province of Tucumán, Argentina). The heavy human usage of the river causes increased levels of dissolved ions, from the dissolution of halite and gypsum, and from the weathering of basic sediments. Correlations demonstrate that sodium chloride and sulphate, and calcium carbonate are the main contributors to dissolved ions in the river. In the polluted region, south of the Celestino Gelsi dam, the main source of calcium and sulphate is the dissolution of gypsum. Large amounts of halite are also dissolved. Weathering of biotite, K-feldspar and albite are suggested by the data. Conductivity, dissolved oxygen and organic matter all indicate severe contamination by organic matter (mainly from sugar-cane processing) in the lower course. The data also demonstrate a substantial improvement in water quality before the discharge of the river at the Río Hondo dam. Data from the Colorado (a tributary of the Salí River) and Medina rivers are also analyzed and compared. 相似文献
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Human-induced coastal landslide reactivation. Monitoring by PSInSAR techniques and urban damage survey (SE Spain) 总被引：1，自引：1，他引：0
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Amado LL Robaldo RB Geracitano L Monserrat JM Bianchini A 《Marine pollution bulletin》2006,52(2):207-213
Biomarkers of exposure (liver metallothionein-like proteins content and catalase and glutathione S-transferase activities) and effect (liver lipoperoxidation and blood cell DNA damage) of contaminants were analyzed in the Brazilian flounder Paralichthys orbignyanus from the Patos Lagoon estuary (Southern Brazil). Flounders were collected for a year in two sites: "Coroa do Boi" (polluted site) and "Saco do Justino" (non-polluted site). Results indicated that micronucleated cells frequency was the best biomarker to distinguish flounders from the two sites. Taken together, data from DNA damage analyses (micronucleus test and comet assay) indicated that flounders from the non-polluted site efficiently repaired the DNA breaks, contrary to those from the polluted site, which probably had their DNA repair system inhibited or exhausted. Furthermore, data from enzyme activities (catalase and GST) and lipid peroxidation indicated that flounders from the polluted site were under oxidative stress in summer and autumn. 相似文献
6.
A. Baran R. Oreiro A. Pigulski F. Pérez Hernández A. Ulla M. D. Reed C. Rodríguez-López P. Moskalik S.-L. Kim W.-P. Chen R. Crowe M. Siwak L. Armendarez P. M. Binder K.-J. Choo A. Dye J. R. Eggen R. Garrido J. M. González Pérez S. L. Harms F.-Y. Huang D. Kozie&#; H.-T. Lee J. MacDonald L. Fox Machado T. Monserrat J. Stevick S. Stewart D. Terry A.-Y. Zhou S. Zo&#;a 《Monthly notices of the Royal Astronomical Society》2009,392(3):1092-1105
7.
Laeonereis acuta (Polychaeta, Nereididae) was collected in an unpolluted (UP) and an polluted (P) site at the Patos Lagoon estuary (Southern Brazil) and maintained under control conditions (UPC and PC, respectively) or exposed to waterborne copper (UPCu and PCu; 500 microg Cu/l), for 48 h. Four groups (aaUPC, aaPC, aaUPCu, and aaPCu) were also pre-exposed for 48 h to ascorbic acid (aa; 0.1 mM) before copper exposure. Histological and morphological alterations, as well as oxygen consumption changes were evaluated. Independently of the sampling site and the pre-exposure to the ascorbic acid, morphological abnormalities were evident in more than 80% of worms exposed to copper. Conspicuous histological changes (coeloma obliteration, cuticle separation from the epidermis, and absence of dorsal vessel) were also observed. In addition, PCu worms showed loss of the digestive epithelium and coiling behavior. Similar oxygen consumption values were observed in control and copper exposed worms. 相似文献
8.
Lithological control of land subsidence induced by groundwater withdrawal in new urban AREAS (Granada Basin,SE Spain). Multiband DInSAR monitoring 
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下载免费PDF全文 Davide Notti Rosa María Mateos Oriol Monserrat Nùria Devanthéry Tomás Peinado Francisco Javier Roldán Francisca Fernández‐Chacón Jorge Pedro Galve Francisco Lamas Jose Miguel Azañón 《水文研究》2016,30(13):2317-2331
Ground subsidence in the southeastern border of the Granada Basin (SE Spain) has been studied using remote sensing techniques. Over the last decades, the region has experienced a huge urban expansion, which has caused a substantial increase in water supply requirements. Water needs are exclusively met by groundwater by means of numerous pumping wells, which exploit a confined detrital aquifer of alluvial fan deposits with a heterogeneous facies distribution. A general piezometric level decline (up to 50 m) has been recorded in the aquifer during the past 30 years that has induced the generation of a subsiding area with oval shape oriented WNW‐ESE just where the new urban areas and pumping wells are located. Subsidence has been monitored by exploiting synthetic aperture radar (SAR) images from ENVISAT (2003–2009) and Cosmo‐SkyMed (2011–2014). A new approach, which combines A‐DInSAR and small‐area persistent scatterer interferometry (PSI) analysis, has been applied obtaining a good accuracy regarding temporal and spatial dimension of the subsidence. ENVISAT data (2003–2009) reveal subsidence rates up to 10–15 mm/year, and Cosmo‐SkyMed (2011–2014) values slightly lower; up to 10 mm/year. Temporal variations in the subsidence velocity are in accordance with the rainfall pattern and piezometric fluctuations in the aquifer. The sector with highest rates of subsidence does not correspond to the area with more intense groundwater exploitation but to the area with greater presence of clays in the confining layer of the aquifer. There is a clear lithological control in the spatial distribution of the ground subsidence. This work integrates detailed geological and hydrogeological data with differential SAR interferometry monitoring with the aim to better understand subsidence processes in detrital aquifers with small‐scale heterogeneity. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
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10.
da Rosa CE de Souza MS Yunes JS Proença LA Nery LE Monserrat JM 《Marine pollution bulletin》2005,50(9):956-964
In January of 2003, a cyanobacterial bloom in the Patos' Lagoon (Southern Brazil) (32 degrees 05'S-52 degrees 12'W) was observed. Water samples were taken to identify the composition and abundance of the bloom, as well as the occurrence of toxins. The effects of this occurrence on the estuarine worm Laeonereis acuta (Polychaeta, Nereididae) was also evaluated. Predominance of cyanobacteria, particularly Anabaena trichomes ( approximately 2.5.10(6) individuals per liter) was observed, and low concentrations of microcystins and anticholinesterasic toxins were detected. Augmented levels of lipid hydroperoxides (LPO) and glutathione-S-transferase activity, and lowering of total protein content were also observed in organisms collected during the bloom event. Although non-toxic, the cyanobacterial bloom could augment the cycle of hyper-oxygenation and hypoxia in the water. During hyperoxia, L. acuta, an oxyconformer, should consume more oxygen, thus augmenting the rate of reactive oxygen species generation. A repeated cycle of hyper-oxygenation and hypoxia would finally induce oxidative stress, as evidenced by the high levels of LPO and glutathione-S-transferase activity. 相似文献