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Pereira Serafim, Maria Angela

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  • Source and impact of lead contamination on δ-aminolevulinic acid dehydratase activity in several marine bivalve species along the Gulf of Cadiz
    Publication . Company, Rui; Serafim, M.A.; Lopes, Belisandra; Cravo, Alexandra; Kalman, J.; Riba, I.; DelValls, T. A.; Blasco, J.; Delgado, J.; Sarmiento, A . M.; Nieto, J. M.; Shepherd, T. J.; Nowell, G.; Bebianno, Maria João
    Coastal areas and estuaries are particularly sensitive to metal contamination from anthropogenic sources and in the last few decades the study of space-time distribution and variation of metals has been extensively researched. The Gulf of Cadiz is no exception, with several rivers draining one of the largest concentrations of sulphide deposits in the world, the Iberian Pyrite Belt (IPB). Of these rivers, the Guadiana, one of the most important in the Iberian Peninsula, together with smaller rivers like the Tinto and Odiel, delivers a very high metal load to the adjacent coastal areas. The purpose of this work was to study the source and impact of lead (Pb) drained from historical or active mining areas in the IPB on the activity of a Pb inhibited enzyme (δ-aminolevulinic acid dehydratase, ALAD) in several bivalve species along the Gulf of Cadiz. Seven marine species (Chamelea gallina, Mactra corallina, Donax trunculus, Cerastoderma edule, Mytilus galloprovincialis, Scrobicularia plana and Crassostrea angulata) were collected at 12 sites from Mazagón, near the mouth of the rivers Tinto and Odiel (Spain), to Cacela Velha (Ria Formosa lagoon system, Portugal). Lead concentrations, ALAD activity and lead isotope ratios ((206)Pb/(204)Pb, (207)Pb/(204)Pb and (208)Pb/(204)Pb) were determined in the whole soft tissues. The highest Pb concentrations were determined in S. plana (3.50±1.09 μg g(-1) Pb d.w.) and D. trunculus (1.95±0.10 μg g(-1) Pb d.w.), while M. galloprovincialis and C. angulata showed the lowest Pb levels (<0.38 μg g(-1) Pb d.w.). In general, ALAD activity is negatively correlated with total Pb concentration. However this relationship is species dependent (e.g. linear for C. gallina ALAD=-0.36[Pb]+0.79; r=0.837; or exponential for M. galloprovincialis ALAD=2.48e(-8.3[Pb]); r=0.911). This indicates that ALAD activity has considerable potential as a biomarker of Pb and moreover, in marine bivalve species with different feeding habits. Lead isotope data showed significant seasonal and spatial changes in bivalve isotopic composition reflecting seasonal and geographic differences in bioaccumulation. Within the study area, Pb can be modelled as a mixing between geogenic Pb and mine-related, discharges of Pb from the IPB. For some sites at the mouth of the Guadiana River, the bivalves show contamination from other anthropogenic sources, such as leaded boat/aviation fuel and/or leaded paint. Finally, the study demonstrates convincingly the need to consider species-specific variation when using bivalve ALAD activity as a biomarker for Pb.
  • Habitat quality of estuarine nursery grounds: Integrating non-biological indicators and multilevel biological responses in Solea senegalensis
    Publication . Fonseca, V. F.; Vasconcelos, R. P.; Tanner, S. E.; Franca, S.; Serafim, M.A.; Lopes, Belisandra; Company, Rui; Bebianno, Maria João; Costa, M. J.; Cabral, H. N.
    Estuaries are highly valuable ecosystems that provide various goods and services to society, such as food provision and supporting nursery habitats for various aquatic species. Estuarine habitat quality assessment is thus critical in managing both ecological and economic value. In this work, various biological and non-biological indicators of habitat quality in estuarine nursery areas were determined, encompassing local environmental conditions, chemical contamination, anthropogenic pressures, juvenile Solea senegalensis condition, biomarkers response to contamination and juvenile density. The various indicators provided an integrated view on habitat quality and their responses were broadly concordant. Nursery quality assessment based on anthropogenic pressure indicators and fish biomarker responses were very similar, signaling nursery areas with higher anthropogenic pressure in Tejo and Ria de Aveiro estuaries. Yet, favorable environmental conditions across all sites could have contributed to lessen the potential hazardous biological effects of exposure to anthropogenic stressors, resulting in soles' fairly good condition and generally high juvenile density. Nevertheless, a mismatch between high juvenile density and high estuarine contribution to adult coastal populations was observed in areas with higher anthropogenic pressures. Although a causal relationship cannot be established, the results emphasize the need to fully understand how the estuarine period spent in estuaries and local processes determine the quantity and quality of juveniles exported to marine adult populations, which is critical to achieve the full potential of the fish production service of estuaries and coastal stock replenishment. (C) 2015 Elsevier Ltd. All rights reserved.
  • A multibiomarker approach in the clam Ruditapes decussatus to assess the impact of pollution in the Ria Formosa lagoon, South Coast of Portugal
    Publication . Cravo, Alexandra; Pereira, C.; Gomes, Tânia; Cardoso, Cátia; Serafim, M.A.; Almeida, Cheila; Rocha, T.; Lopes, Belisandra; Company, Rui; Medeiros, A.; Norberto, R.; Pereira, R.; Araújo, O.; Bebianno, Maria João
    The Ria Formosa lagoon is an ecosystem whose water quality reflects the anthropogenic influence upon the surrounding areas. In this lagoon, the clam Ruditapes decussatus has a great economical importance and has been widely used as a biomonitor. A multibiomarker approach (d-aminolevulinic acid dehy- dratase, metallothionein, lipid peroxidation, acetylcholinesterase, alkali-labile phosphates, DNA damage) was applied to assess the environmental quality of this ecosystem and the accumulation of contaminants and their potential adverse effects on clams. Clams were sampled in different shellfish beds in the period between July 2007 and December 2008 and abiotic parameters (temperature, salinity, pH and dissolved oxygen of seawater and organic matter in the sediment), condition index, metals (Cd, Cu, Zn, Ni, Pb), TBTs and PAHs concentrations were measured in clam tissues. Data was integrated using Principal Component Analyses and biomarker indices: IBR (Integrated Biomarker Response) and HSI (Health Status Index). This multibiomarker approach enabled discrimination of a time and space trend between sites with different degrees of anthropogenic contamination, identifying one of them (site 2) as the most stressful and summer months as the most critical period for clams due to an increase of environmental stress (anthropogenic pressure along with extreme environmental conditions, e.g. temperature, dissolved oxygen, organic matter in the sediments, etc). The selected biomarkers provided an integrated response to assess the environmental quality of the system, proving to be a useful approach when complex mixtures of contaminants occur.
  • Short-term variability of multiple biomarker response in fish from estuaries: Influence of environmental dynamics
    Publication . Fonseca, V.F.; França, S.; Vasconcelos, R.P.; Serafim, M.A.; Company, Rui; Lopes, Belisandra; Bebianno, Maria João; Cabral, H.N.
    Short-term variability in biomarker responses and the effects of temperature and salinity variation were explored in three fish species (Dicentrarchus labrax, Solea senegalensis and Pomatoschistus microps) occurring in the Tejo estuary. Short-term variability in biomarkers was observed in all species although no pattern was discerned over time (days to weeks). Antioxidant enzymes activity (superoxide dismutase (SOD) and catalase (CAT)) showed low temporal variability, indicating some constancy or baseline level in antioxidant responses. Only CAT activity in S. senegalensis was correlated with temperature, suggesting that exposure to contaminants triggered antioxidant acclimation. Higher short-term variability was observed in xenobiotic biotransformation enzymes activity (phase I ethoxyresorufin O-deethylase (EROD) and phase II glutathione S-transferase (GST)). Yet a significant correlation between EROD and GST in D. labrax and S. senegalensis suggests a concomitant response to contaminants. Moreover the lack of correlation between xenobiotic biotransformation enzymes and abiotic variables on concordant time scales, suggest a high specificity of these biomarkers to chemical exposure, rather than high variability due to environmental dynamics.
  • Sub-lethal effects of cadmium on the antioxidant defence system of the hydrothermal vent mussel Bathymodiolus azoricus
    Publication . Company, Rui; Serafim, M.A.; Cosson, Richard P.; Fiala-Médioni, Aline; Camus, Lionel; Serrão-Santos, Ricardo; Bebianno, Maria João
    The mussel Bathymodiolus azoricus is one of the most abundant species in the Mid-Atlantic Ridge hydrothermal vents and is continually exposed to the high-temperature venting fluids containing high metal concentrations and enriched in sulphides and methane, which constitute a potential toxic environment for marine species. The aim of this study was to assess the effects of a sub-lethal Cd concentration on the antioxidant defence system of this mussel. B. azoricus were collected at Menez Gwen vent site (37 degrees 51'N, 32 degrees 31'W) and exposed to Cd (50 microg l(-1)) during 24 days, followed by a depuration period of six days. A battery of stress related biomarkers including antioxidant enzymes (superoxide dismutase-SOD, catalase-CAT; glutathione peroxidases-GPx), metallothioneins (MT), lipid peroxidation (LPO) and total oxyradical scavenging capacity (TOSC) were measured in the gills and mantle of B. azoricus. Cd was accumulated linearly during the exposure period in both tissues and no significant elimination occurred after the 6 days of depuration. Antioxidant enzymes activities were significantly higher in the gills. Cyt-SOD, T-GPx and Se-GPx were induced during the experiment but this was also observed in control organisms. Mit-SOD and CAT activities remained relatively unchanged. MT levels increased linearly in the gills of exposed mussels in the first 18 days of exposure. No significant differences were observed between LPO levels of control and exposed mussels. TOSC levels remained unchanged in control and exposed mussels. This suggests that although Cd is being accumulated in the tissues of exposed mussels, MT defence system is enough to detoxify the effect of Cd accumulated in the tissues. Furthermore, other factors besides the presence of Cd are influencing the antioxidant defence system in B. azoricus.
  • Hepatic metallothionein concentrations in the golden grey mullet (Liza aurata): relationship with environmental metal concentrations in a metal-contaminated coastal system in Portugal
    Publication . Oliveira, M.; Ahmad, I.; Maria, Vera L.; Serafim, A.; Bebianno, Maria João; Pacheco, M.; Santos, M.A.
    This field survey was designed to assess the environmental metal contamination status of Ria de Aveiro (Portugal). To achieve that goal, the concentrations of Cd, Hg, Cu and Zn in the sediments and water were assessed and Liza aurata hepatic metallothionein (MT) determined. The relationships between MT and environmental metal concentrations and hydrological factors were examined. Results revealed a wide distribution of metals both in water and sediments throughout the lagoon, mainly at Rio Novo do Principe (RIO) and Laranjo (LAR), at concentrations that may affect biota. MT concentrations were higher at the sites with high metal content (RIO and LAR). A significant positive correlation was found between MT and Cd in the sediments as well as with MT and Hg and Cu in the water. Moreover, a negative correlation between MT and salinity was found. Thus, the current data support MT use as a biomarker of metal exposure emphasizing the importance of hydrological parameters in its concentrations. Results suggest the continued monitoring of this lagoon system.
  • Multi-biomarker responses to estuarine habitat contamination in three fish species: Dicentrarchus labrax, Solea senegalensis and Pomatoschistus microps
    Publication . Fonseca, V. F.; França, S.; Serafim, M.A.; Company, Rui; Lopes, Belisandra; Bebianno, Maria João; Cabral, H. N.
    Several biomarker responses were determined in three fish species, Dicentrarchus labrax, Solea senegalensis and Pomatoschistus microps, from two estuaries of the Portuguese coast, Ria de Aveiro and Tejo. Both estuaries have significant anthropogenic influences from multiple sources (industrial, agricultural and shipping activities), which was evident from sediment chemical characterization concerning metal (copper, zinc, nickel, lead and chromium) and polycyclic aromatic hydrocarbon (PAH) concentrations. Spatial variability in fish responses was observed across species for most biomarkers of exposure [the activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), ethoxyresorufin O-deethylase (EROD) and glutathione S-transferase (GST), and metallothionein concentrations (MT)] and effect biomarkers [lipid peroxidation (LPO), RNA to DNA ratio (R:D), protein and lipid content]. In general, the interspecific differences in biomarker responses were greater than the spatial differences, due to differences in the behavior and habitat use of the species. Nevertheless, similarities were also observed considering both chemical load and biomarker responses. In highly polluted sites fish showed in general a significant antioxidant enzyme induction, associated with decreased R:D values, while fish from the least impacted site had little enzyme induction and better condition indices (high R:D and low LPO values). EROD activity was also higher for all species in the Tejo than Ria de Aveiro estuary, despite the generally higher total PAH measured in Ria de Aveiro, most likely due to a higher proportion of 4 and 6-ring PAHs, considered more toxic than low molecular weight PAHs, in the Tejo. In conclusion, this multi-biomarker approach considering multiple species provided improved understanding of the diverse responses and effects of exposure to contaminants and the effective risk it poses for different fish species.
  • Protein expression profiles in Bathymodiolus azoricus exposed to cadmium
    Publication . Company, Rui; Antúnez, Oreto; Cosson, Richard P.; Serafim, M. A.; Shillito, Bruce; Cajaraville, Miren; Bebianno, Maria João; Torreblanca, Amparo
    Proteomic changes in the "gill-bacteria complex" of the hydrothermal vent mussel B. azoricus exposed to cadmium in pressurized chambers ((Incubateurs Pressurises pour l'Observation en Culture d'Animaux Marins Profonds - IPOCAMP) were analyzed and compared with the non-exposed control group. 2-D Fluorescence Difference Gel Electrophoresis (2D-DIGE) showed that less than 1.5% of the proteome of mussels and symbiotic bacteria were affected by a short-term (24 h) Cd exposure. Twelve proteins of the more abundant differentially expressed proteins of which six were up-regulated and six were down-regulated were excised, digested and identified by mass spectrometry. The identified proteins included structural proteins (actin/actin like proteins), metabolic proteins (calreticulin/calnexin, peptidyl-prolyl cis-trans isomerase, aminotransferase class-III, electron transfer flavoprotein, proteasome, alpha-subunit and carbonic anhydrase) and stress response proteins (chaperone protein htpG, selenium-binding protein and glutathione transferases). All differently expressed proteins are tightly connected to Cd exposure and are affected by oxidative stress. It was also demonstrated that B. azoricus was well adapted to Cd contamination therefore B. azoricus from hydrothermal vent areas may be considered a good bioindicator.
  • Assessment of Iodine Deficiency in Sao Tome e Principe Children
    Publication . Serafim, Angela; Martins-Ferreira, Ana; Serafim, P.; Pedro, Paulo; Rodrigues, Celia; Coutinho, Miguel; Figueiredo, Teresa
    Introduction: Iodine deficiency still constitutes one of the major public health problems in the world, having a serious social and economic impact. This global problem involves about 130 countries, including Sao Tome and Principe (STP). The aim of the present study was to determine the prevalence and distribution of iodine deficiency in male children within different host institutions of STP. Material and Methods: A descriptive, cross-sectional observational study was conducted with a non-probabilistic sample (for convenience) of 116 children. Children were aged from 6 to 17 years, with an overall mean age of 11.1 +/- 3.2 years. Iodine intake was evaluated in 6 districts of STP, through two indirect indices: (i) urine iodine (UI) determinations (ii) prevalence of goiter evaluated by cervical ultrasound. Results: The global median UI value was 109 mu g/L (P20: 78.2 mu g/Land P80: 140.3 mu g/L), with 16.4% of children <50 mu g/L and 40.5% <100 mu g/L. Considering children aged 6 - 12 years, 15.6% showed U1 <50 mu g / L, while in group aged 13-17 years this percentage increased to 17.9%. These values fulfill WHO criteria of sufficient region in iodine. On the other hand, the goiter prevalence against age was 29.7% and against Body Surface Area (BSA) was 44.6%, which is much higher than the cut-off established by the WHO (5%). Conclusion: The iodine deficiency and endemic goiter in STP are currently a public health problem. Therefore, it will be necessary to ensure that the interventions carried out are efficiently monitored, in order to eradicate endemic goiter, without risks of hyperthyroidism.
  • Effect of a polymetallic mixture on metal accumulation and metallothionein response in the clam Ruditapes decussatus
    Publication . Serafim, Angela; Bebianno, Maria João
    The toxic effects of metals are related to changes in natural physiological and biochemical processes in organisms, which are not easily detected. Marine invertebrates developed strategies to survive in the presence of toxic metal levels, by the removal of these compounds from the soluble fraction of the cell through different processes, including the synthesis of metallothionein (MT). To better understand the effect of Cd, Cu and Zn in MT response it is important to consider that in their natural environment these metals are normally mixed. The exposure to a metal mixture result in toxicological interactions that produce different biological responses when compared to the effects of a single metal exposure. The aim of this study was to assess metal accumulation and MT response in different tissues of the clam Ruditapes decussatus exposed to a mixture of sublethal Cd, Cu and Zn concentrations. Kinetic models were applied to determine metal uptake and loss to better predict and understand the detoxification mechanisms in this species. The kinetic model showed that the effect of this polymetallic exposure compared to a single exposure to these metals caused different metal uptake and loss rates in several tissues. Moreover, the exposure of R. decussatus to a polymetallic mixture caused an increase in MT induction compared to a single metal exposure. This is probably related to the interaction between the different metals and their different affinity to this protein. Metal interactions within aquatic organisms are very important in MT synthesis and the effect of polymetallic mixtures in the environment must be taken into account in field studies.