Browsing by Author "Pinto, E."
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- Effects and bioaccumulation of gold nanoparticles in the gilthead seabream (Sparus aurata) – Single and combined exposures with gemfibrozilPublication . Barreto, A.; Luis, L.G.; Pinto, E.; Almeida, A.; Paíga, Paula; Santos, Lúcia H.M.L.M.; Delerue-Matos, Cristina; Trindade, T.; Soares, A.M.V.M.; Hylland, K.; Loureiro, S.; Oliveira, M.Gold nanoparticles (AuNPs) are found in a wide range of applications and therefore expected to present increasing levels in the environment. There is however limited knowledge concerning the potential toxicity of AuNPs as well as their combined effects with other pollutants. Hence, the present study aimed to investigate the effects of AuNPs alone and combined with the pharmaceutical gemfibrozil (GEM) on different biological responses (behaviour, neurotransmission, biotransformation and oxidative stress) in one of the most consumed fish in southern Europe, the seabream Sparus aurata. Fish were exposed for 96 h to waterborne 40 nm AuNPs with two coatings - citrate and polyvinylpyrrolidone (PVP), alone or combined with GEM. Antioxidant defences were induced in liver and gills upon both AuNPs exposure. Decreased swimming performance (1600 μg.L-1) and oxidative damage in gills (4 and 80 μg.L-1) were observed following exposure to polyvinylpyrrolidone coated gold nanoparticles (PVP-AuNPs). Generally, accumulation of gold in fish tissues and deleterious effects in S. aurata were higher for PVP-AuNPs than for cAuNPs exposures. Although AuNPs and GEM combined effects in gills were generally low, in liver, they were higher than the predicted. The accumulation and effects of AuNPs showed to be dependent on the size, coating, surface charge and aggregation/agglomeration state of nanoparticles. Additionally, it was tissue' specific and dependent on the presence of other contaminants. Although, gold intake by humans is expected to not exceed the estimated tolerable daily intake, it is highly recommended to keep it on track due to the increasing use of AuNPs.
- Effects of single and combined exposures of gold (nano versus ionic form) and gemfibrozil in a liver organ culture of Sparus aurataPublication . Barreto, A.; Carvalho, A.; Silva, D.; Pinto, E.; Almeida, A.; Paíga, P.; Correia-Sá, L.; Delerue-Matos, C.; Trindade, T.; Soares, A.M.V.M.; Hylland, K.; Loureiro, S.; Oliveira, M.In vitro methods have gained rising importance in ecotoxicology due to ethical concerns. The aim of this study was to assess the single and combined in vitro effects of gold, as nanoparticle (AuNPs) and ionic (Au+) form, and the pharmaceutical gemfibrozil (GEM). Sparus aurata liver organ culture was exposed to gold (4 to 7200 μg·L−1), GEM (1.5 to 15,000 μg·L−1) and combination 80 μg·L−1 gold +150 μg·L−1 GEM for 24 h. Endpoints related with antioxidant status, peroxidative/genetic damage were assessed. AuNPs caused more effects than Au+, increasing catalase and glutathione reductase activities and damaging DNA and cellular membranes.
- Genotoxicity of gold nanoparticles in the gilthead seabream (Sparus aurata) after single exposure and combined with the pharmaceutical gemfibrozilPublication . Barreto, A.; Luis, L.G.; Pinto, E.; Almeida, A.; Paíga, Paula; H.M.L.M. Santos, Lúcia; Delerue-Matos, Cristina; Trindade, T.; Soares, A.M.V.M.; Hylland, K.; Loureiro, S.; Oliveira, M.Due to their diverse applications, gold nanoparticles (AuNPs) are expected to increase of in the environment, although few studies are available on their mode of action in aquatic organisms. The genotoxicity of AuNPs, alone or combined with the human pharmaceutical gemfibrozil (GEM), an environmental contaminant frequently detected in aquatic systems, including in marine ecosystems, was examined using gilthead seabream erythrocytes as a model system. Fish were exposed for 96 h to 4, 80 and 1600 μg L-1 of 40 nm AuNPs with two coatings - citrate or polyvinylpyrrolidone; GEM (150 μg L-1); and a combination of AuNPs and GEM (80 μg L-1 AuNPs + 150 μg L-1 GEM). AuNPs induced DNA damage and increased nuclear abnormalities levels, with coating showing an important role in the toxicity of AuNPs to fish. The combined exposures of AuNPs and GEM produced an antagonistic response, with observed toxic effects in the mixtures being lower than the predicted. The results raise concern about the safety of AuNPs and demonstrate interactions between them and other contaminants.
- Noncompliance to iodine supplementation recommendation is a risk factor for iodine insufficiency in Portuguese pregnant women: results from the IoMum cohortPublication . Matta Coelho, C.; Guimarães, J.; Bracchi, I.; Xavier Moreira, N.; Pinheiro, C.; Ferreira, P.; Pestana, D.; Barreiros Mota, I.; Cortez, A.; Prucha, C.; Martins, C.; Pinto, E.; Almeida, A.; Delerue-Matos, Cristina; Dias, C. C.; Moreira-Rosário, A.; Ribeiro de Azevedo, L. F.; Fernandes, Virgínia; Ramalho, C.; Calhau, C.; Brantsæter, A.-L.; Costa Leite, J.; Keating, E.Purpose After a recommendation for iodine supplementation in pregnancy has been issued in 2013 in Portugal, there were no studies covering iodine status in pregnancy in the country. The aim of this study was to assess iodine status in pregnant women in Porto region and its association with iodine supplementation. Methods A cross-sectional study was conducted at Centro Hospitalar Universitário São João, Porto, from April 2018 to April 2019. Pregnant women attending the 1st trimester ultrasound scan were invited to participate. Exclusion criteria were levothyroxine use, gestational age < 10 and ≥ 14 weeks, non-evolutive pregnancy at recruitment and non-signing of informed consent. Urinary iodine concentration (UIC) was measured in random spot urine by inductively coupled plasma-mass spectrometry. Results Median UIC was 104 μg/L (IQR 62–189) in the overall population (n = 481) of which 19% had UIC < 50 µg/L. Forty three percent (n = 206) were not taking an iodine-containing supplement (ICS) and median UIC values were 146 µg/L (IQR 81–260) and 74 µg/L (IQR 42–113) in ICS users and non-users, respectively (p < 0.001). Not using an ICS was an independent risk factor for iodine insufficiency [adjusted OR (95% CI) = 6.00 (2.74, 13.16); p < 0.001]. Iodised salt use was associated with increased median iodine-to-creatinine ratio (p < 0.014). Conclusions A low compliance to iodine supplementation recommendation in pregnancy accounted for a mild-to-moderately iodine deficiency. Our results evidence the need to support iodine supplementation among pregnant women in countries with low household coverage of iodised salt.
- Noncompliance to iodine supplementation recommendation is a risk factor for iodine insufficiency in portuguese pregnant women: results from the IoMum cohortPublication . Matta Coelho, C.; Guimarães, J.; Bracchi, I.; Xavier Moreira, N.; Pinheiro, C.; Ferreira, P.; Pestana, D.; Barreiros Mota, I.; Cortez, A.; Prucha, C.; Martins, C.; Pinto, E.; Almeida, A.; Delerue‑Matos, C.; C. Dias, C.; Moreira‑Rosário, A.; F. Ribeiro de Azevedo, L.; Cruz Fernandes, V.; Ramalho, C.; Calhau, C.; ‑L. Brantsæter, A.; Costa Leite, J.; Keating, E.After a recommendation for iodine supplementation in pregnancy has been issued in 2013 in Portugal, there were no studies covering iodine status in pregnancy in the country. The aim of this study was to assess iodine status in pregnant women in Porto region and its association with iodine supplementation. A cross-sectional study was conducted at Centro Hospitalar Universitário São João, Porto, from April 2018 to April 2019. Pregnant women attending the 1st trimester ultrasound scan were invited to participate. Exclusion criteria were levothyroxine use, gestational age<10 and≥14 weeks, non-evolutive pregnancy at recruitment and non-signing of informed consent. Urinary iodine concentration (UIC) was measured in random spot urine by inductively coupled plasma-mass spectrometry. Median UIC was 104 μg/L (IQR 62–189) in the overall population (n=481) of which 19% had UIC<50 µg/L. Forty three percent (n=206) were not taking an iodine-containing supplement (ICS) and median UIC values were 146 µg/L (IQR 81–260) and 74 µg/L (IQR 42–113) in ICS users and non-users, respectively (p<0.001). Not using an ICS was an independent risk factor for iodine insufciency [adjusted OR (95% CI)=6.00 (2.74, 13.16); p<0.001]. Iodised salt use was associated with increased median iodine-to-creatinine ratio (p<0.014). A low compliance to iodine supplementation recommendation in pregnancy accounted for a mild-to-moderately iodine defciency. Our results evidence the need to support iodine supplementation among pregnant women in countries with low household coverage of iodised salt.