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1.
Sci Total Environ ; 581-582: 289-296, 2017 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-28087073

RESUMO

Octopus vulgaris is a sedentary organism that inhabits coastal waters being exposed to anthropogenic compounds. Lead concentration in coastal environments reflects many processes and activities namely weathering, industrial and domestic discharges, and atmospheric deposition. Since lead isotopic composition is little affected by kinetic processes occurring between source and sink, its signature has been used to identify different Pb sources. After a short-term heavy rainfall, hundreds of octopus appeared dead in two Portuguese coastal areas. Histopathology and Pb levels and its stable isotopes were determined in tissues, such as digestive gland, of stranded octopus and compared to alive specimens, sediments and runoff material from the same areas. Histology results showed severe damage in stranded octopus tissues suggesting that death was probably associated to multiple organ failure linked to hypertrophy and exudates input. In addition, Pb in stranded specimens reach concentrations up to one order of magnitude above the levels reported for alive octopus. Pb isotopic signatures in stranded organisms were closer to runoff material pointing to a similar origin of Pb. In summary, the results in this study showed that a short-term runoff event might change abruptly the salinity leading to the disruption of the osmoregulation function of octopus and consequently leading to its death. The analyses of stable isotopic Pb signature in octopus tissues corroborate these results and points to a change in the Pb source due to runoff after the storm water event. Pb stable isotopes in octopus proved to be an adequate tool to confirm the cause of death and linking it to the environment conditions.


Assuntos
Monitoramento Ambiental , Chumbo/toxicidade , Octopodiformes , Poluentes Químicos da Água/toxicidade , Animais , Isótopos , Chuva , Água
2.
Mar Pollut Bull ; 84(1-2): 135-46, 2014 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-24933166

RESUMO

Upper sediments (0-5 cm) were sampled in 94 sites of water bodies of the fifteen Portuguese estuaries characterized by distinct settings of climate, topography and lithology, and marked by diverse anthropogenic pressures. Confined areas recognized as highly anthropogenic impacted, as well as areas dominated by erosion or frequently dredged were not sampled. Grain size, organic carbon (Corg), Al and trace elements (As, Cd, Co, Cr, Cu, Hg, Ni, Pb and Zn) were determined. Normalisation of trace element concentrations to Al and Corg, correlations between elements and Principal Component Analysis (PCA) allowed identifying elemental associations and the relevance of grain-size, lithology and anthropogenic inputs on sediment chemical composition. Whereas grain-size is the dominant effect for the majority of the studied estuaries, the southern estuaries Mira, Arade and Guadiana are dominated by specific lithologies of their river basins, and anthropogenic effects are identified in Ave, Leça, Tagus and Sado. This study emphasizes how baseline values of trace elements in sediments may vary within and among estuarine systems.


Assuntos
Estuários , Sedimentos Geológicos/química , Metais Pesados/química , Animais , Monitoramento Ambiental , Portugal , Análise de Componente Principal , Rios/química , Oligoelementos/análise
3.
Transplant Proc ; 45(3): 1073-5, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23622629

RESUMO

BACKGROUND: Randomized clinical trials have supported the use of interleukin-2 receptor (IL-2R) antagonists as induction therapy in renal transplantation. This strategy has reduced the incidence of acute rejection episodes (ARE) but not improved graft survival. Our objective was to investigate the impact of induction therapy using the IL-2R antagonist basiliximab, as compared with no induction therapy, on relevant clinical outcomes-initial length of stay, incidence of ARE, long-term graft function, and graft survival. METHODS: We retrospectively reviewed the medical records of patients transplanted in a tertiary care center between 1996 and 2011. We selected patients who received cyclosporine, mycophenolate mofetil, and prednisolone (n = 334) to classify as: no induction therapy (n = 131; group 1); induction therapy with basiliximab (n = 203; group 2). Estimated glomerular filtration rate (eGFR) was assessed with the 4-variable Modification of Diet in Renal Disease (MDRD) equation. RESULTS: Mean follow-up was 72.7 ± 35.4 months. Patients who received basiliximab had a shorter mean hospital stay (19.2 versus 22.5 days; P = .02), lower incidence of ARE (10.8% versus 23.7%; P = .02) and better graft function post transplantation at 12 months (mean eGFR 59.4 ± 18.4 versus 54.8 ± 18.7 mL/min/1.73 m(2); P = .015) and 5 years (mean eGFR 64.1 ± 21.5 versus 55.4 ± 19.6 mL/min/1.73 m(2); P = .009). On multivariate analysis, induction therapy with basiliximab was independently associated with a lower incidence of ARE and better graft function at 1 and 5 years after transplantation. There was no difference in 5-year graft survival between the two groups (log-rank: P = .54). CONCLUSIONS: Induction therapy with basiliximab was associated with a reduced incidence of ARE and better long-term graft function but no difference in 5-year graft survival.


Assuntos
Anticorpos Monoclonais/administração & dosagem , Transplante de Rim , Proteínas Recombinantes de Fusão/administração & dosagem , Adulto , Basiliximab , Feminino , Sobrevivência de Enxerto , Humanos , Masculino , Pessoa de Meia-Idade , Cuidados Pré-Operatórios , Estudos Retrospectivos
4.
Arch Environ Contam Toxicol ; 64(4): 617-31, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23299253

RESUMO

Surface sediments were collected in August 2009 from 49 sites along the Minho estuary (between Tui and Caminha) and analyzed for grain size, organic carbon (Corg) and total nitrogen (Ntot) contents, and major (silicon [Si], aluminum [Al], iron [Fe], calcium [Ca], magnesium [Mg], sodium [Na], potassium [K], titanium [Ti], and mangesese [Mn]) and trace element (arsenic [As], chromium [Cr], copper [Cu], mercury [Hg], lithium [Li], lead [Pb], rubidium [Rb], tin [Sn], and zinc [Zn]) concentrations. Factor analysis was used to decrease 22 selected variables into 4 factors accounting for 85.9 % of the total variance explained, suggesting distinct elemental sources or sediment components affecting their spatial distributions. Although factors 1 (detrital component; elements strongly associated with fine- [Na, Mg, Ti, Li, Cr, Cu, Fe, Al, Zn, Ca, and As] and coarse-grained sediments [Si, K, Rb; mean grain-size [MGS]) and 3 (Fe-Mn oxyhydroxide sediment component; Fe, Mn, As, fine fraction) are interpreted as reflecting predominance of natural contributions, factors 2 (urban and industrial contamination: sediment components [Pb, Hg, organic carbon [Corg], total nitrogen [Ntot] and 4 (components associated with contamination by nautical activities; the association of tin [Sn] and calcium [Ca]) seem to indicate anthropogenic contributions). Nevertheless, the influence of elemental contributions derived from tungsten (W)-Sn mineralizations and those resulting from mining activities can also contribute to the obtained geochemical associations and should be considered. Spatial distribution of dominant factor scores shows the dominance of factors 2 and 4 between Tui and Vila Nova de Cerveira, whereas samples dominated by factors 3 and 1 are found between Ilha da Boega and Seixas and in the Caminha areas, respectively. Despite the dominance of factor score 1 in the Caminha area, the distribution pattern of dominant factor scores shows samples dominated by other factor scores that can be explained by dredging activities in this river sector that restore ancient sedimentary characteristics or expose contaminated sediments. Through the identification of sample locations dominated by factors associated with contamination, it will be possible to select them as priority areas where new environmental (e.g., toxicity tests, organic Sn compounds, tracers of sewage contamination) studies should be implemented in the future.


Assuntos
Sedimentos Geológicos/química , Metais Pesados/análise , Rios/química , Poluentes Químicos da Água/análise , Estuários , Portugal
5.
Environ Monit Assess ; 185(7): 5937-50, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23179725

RESUMO

Forty-nine surface sediment samples from the Minho estuary sector between Tui and Caminha were analyzed for grain-size contents, Al, As, Cr, Cu, Hg, Li, Pb, Sn, and Zn concentrations. Selected heavy metal (Cu, Cr, Hg, and Zn) and metalloid (As and Sn) distributions were normalized against Al and Li with the main goal of compensating for natural grain-size variability and to separate natural from anthropogenic contributions, by using a combination of normalization techniques (definition of regional geochemical baselines (RGB) and determination of enrichment factors (EF)). Lead did not reveal a significant relationship with Al and Li. Aluminum explained more variance than Li for As, Cu, Hg, and Zn. Assuming the general non-impacted metal character of the Minho River estuary sediments, RGBs are defined for differentiating between natural and anthropogenic contributions. Based on RGB defined for each heavy metal/metalloid, the degree of enrichment is estimated through the determination of EF. Despite the relatively low total heavy metal and metalloid concentrations, the defined RGB identifies a set of samples characterized by presenting As, Cu, Cr, Hg, and Zn enrichments relatively to expected natural levels. Mercury is the element showing the highest level of enrichment relative to the baseline values being spread through all the study area. Tin present enrichments relatively to Al and or Li always lower than 1.5 suggesting natural contributions.


Assuntos
Monitoramento Ambiental , Estuários , Sedimentos Geológicos/química , Metaloides/análise , Metais Pesados/análise , Poluentes Químicos da Água/análise , Coleta de Dados , Metaloides/normas , Metais Pesados/normas , Portugal , Rios , Poluentes Químicos da Água/normas
6.
Environ Pollut ; 148(2): 418-27, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17280758

RESUMO

Metal concentrations (Al, Cr, Cu, Ni, Pb and Zn) from the DGM-INETI archive data set have been examined for sediments collected during the 1970s from 267 sites on the Portuguese shelf. Due to the differences in the oceanographic and sedimentological settings between western and Algarve coasts, the archive data set is split in two segments. For both shelf segments, regional geochemical baselines (RGB) are defined using aluminium as a reference element. Seabed samples recovered in 2002 from four distinct areas of the Portuguese shelf are superimposed on these models to identify and compare possible metal enrichments relative to the natural distribution. Metal enrichments associated with anthropogenic influences are identified in three samples collected nearby the Tejo River and are characterised by the highest enrichment factors (EF; EF(Pb)<3, EF(Zn)<4). EF values close to 1 suggest a largely natural origin for metal distributions in sediments from the other areas included in the study.


Assuntos
Poluentes Ambientais/análise , Sedimentos Geológicos/química , Metais Pesados/análise , Alumínio/análise , Cromo/análise , Cobre/análise , Monitoramento Ambiental/métodos , Chumbo/análise , Níquel/análise , Portugal , Fatores de Tempo , Zinco/análise
7.
Sci Total Environ ; 367(1): 466-80, 2006 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-16701790

RESUMO

Although high energy shelves are usually ignored in environmental studies, the fine fractions of sandy deposits and the restricted areas of silty clayey deposits record contaminant loading history and can represent important components for understanding processes and fluxes in a system perspective. The main aim of this work is identify trends in historical pollution in three accumulation areas of the western Portuguese shelf that are characterised by different oceanographic and sedimentologic conditions. The vertical distribution of major (Al, Ca, Fe, Mg, Mn and S) and trace elements (Cr, Cu, Li, Ni, Pb, Sc, Sr and Zn), (210)Pb and the fine fraction contents, are documented. The (210)Pb distributions with depth confirm recent accumulation in the study areas and provide a chronologic basis. Factor analysis is used to classify the number of variables into detrital, biogenic and anthropogenic factors that may reflect common metal sources or sedimentary processes. Related to both bioturbation and hydrodynamic processes occurring at water-depths greater than 100 m, the northern Ave-Douro area has a 5-7 cm mixed-layer at the surface affecting the deposition signal. In the Lis area, on the central shelf, heavy metal contents normalised to aluminium indicate slight anthropogenic enrichment in Pb and Zn contents since the beginning of the 20th century and higher levels from the 1950s until the present. These historical trends can reflect changes in the industrial activity and in the combustion of leaded gasoline. Down-core profiles from the southern Mira area reveal metal enrichments that may be caused by early diagenetic remobilisation and precipitation. The use of dated profiles extending across the record of industrial development allows both enrichment factors and excess (anthropogenic) metal fluxes to be compared with historical changes.


Assuntos
Monitoramento Ambiental/métodos , Sedimentos Geológicos/química , Radioisótopos de Chumbo/análise , Metais Pesados/análise , Poluentes Químicos da Água/análise , Portugal
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