Browsing by Author "Costa, C."
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- Alterações fenotípicas e genéticas do metabolismo do ferro numa população portuguesa com doença de Alzheimer: potenciais implicações no conhecimento da fisiopatologia e no diagnóstico desta demênciaPublication . Crespo, A.C.; Silva, B.; Marques, L.; Marcelino, E.; Maruta, C.; Costa, S.; Timóteo, A.; Vilares, A.; Couto, F.S.; Faustino, Paula; Correia, A.P.; Verdelho, A.; Porto, G.; Guerreiro, M.; Herrero, A.; Costa, C.; Mendonça, A.; Martins, M.; Costa, L.
- Analysis of cellular damage induced by silica-coated iron oxide nanoparticles on neuronal cellsPublication . Laffon, Blanca; Kiliç, G.; Fernandez Bertólez, N.; Costa, C.; Costa, S.; Teixeira, J.P.; Pásaro, E.; Valdiglesias, V.The objective of this work was to evaluate toxicity induced by silica-coated ION on a human neuronal cell line (SHSY5Y).
- Avaliação do Estado Nutricional de crianças dos 0-3 anos da USF Cidadela, CascaisPublication . Leal, S.; Costa, C.; Arruda, N.; Vasco, Elsa; Alvito, Paula
- BiomonitoringPublication . Costa, C.; Teixeira, João PauloBiomonitoring concerns the systematic measurement of compounds and/or detection of cell or cell molecules alterations in living organisms with the purpose of identifying or assessing potential hazardous exposure and effects to chemicals. Biomonitoring presents a wide range of advantages over environmental monitoring and has been considered to be a valuable tool for both ecological and human health surveillance. Cautious interpretation of data is one of the most sensitive issues on this matter. Still, the development and application of biomonitoring lead to improved knowledge of the effects of chemicals on living organisms and at the same time to increased protection of public health and environment.
- Biomonitoring of several toxic metal(loid)s in different biological matrices from environmentally and occupationally exposed populations from Panasqueira mine area, PortugalPublication . Coelho, P.; Costa, S.; Costa, C.; Silva, S.; Walter, A.; Ranville, J.; Pastorinho, M.R.; Harrington, C.; Taylor, A.; Dall'Armi, V.; Zoffoli, R.; Candeias, C.; da Silva, E.F.; Bonassi, S.; Laffon, B.; Teixeira, João PauloIn the Panasqueira mine area of central Portugal, some environmental media show higher metal(loid) concentrations when compared with the local geochemical background and the values proposed in the literature for these environmental media. In order to evaluate the effect of the external contamination on selected indexes of internal dose, As, Cd, Cu, Cr, Fe, Hg, Mg, Mn, Mo, Ni, Pb, S, Se, Si, and Zn were quantified by inductively coupled plasma mass spectrometry and inductively coupled plasma optical emission spectrometry in blood, urine, hair and nail samples from individuals environmentally (N = 41) and occupationally exposed (N = 41). A matched control group (N = 40) was also studied, and data from the three groups were compared. Results obtained agreed with those reported by environmental studies performed in this area, pointing to populations living nearby and working in the mine being exposed to metal(loid)s originated from mining activities. Arsenic was the element with the highest increase in exposed populations. The concentration of other elements such as Cr, Mg, Mn, Mo, Ni, Pb, S, Se, and Zn was also increased, although at a lesser extent, specifically in the individuals environmentally exposed and in females. These findings confirm the need for competent authorities to act as soon as possible in this area and implement strategies aimed to protect exposed populations and the entire ecosystem.
- Comparative study on effects of two different types of titanium dioxide nanoparticles on human neuronal cellsPublication . Valdiglesias, V.; Costa, C.; Sharma, V.; Kiliç, G.; Pásaro, E.; Teixeira, João Paulo; Dhawan, A.; Laffon, B.Titanium dioxide (TiO2) are among most frequently used nanoparticles (NPs). They are present in a variety of consumer products, including food industry in which they are employed as an additive. The potential toxic effects of these NPs on mammal cells have been extensively studied. However, studies regarding neurotoxicity and specific effects on neuronal systems are very scarce and, to our knowledge, no studies on human neuronal cells have been reported so far. Therefore, the main objective of this work was to investigate the effects of two types of TiO₂ NPs, with different crystalline structure, on human SHSY5Y neuronal cells. After NPs characterization, a battery of assays was performed to evaluate the viability, cytotoxicity, genotoxicity and oxidative damage in TiO₂ NP-exposed SHSY5Y cells. Results obtained showed that the behaviour of both types of NPs resulted quite comparable. They did not reduce the viability of neuronal cells but were effectively internalized by the cells and induced dose-dependent cell cycle alterations, apoptosis by intrinsic pathway, and genotoxicity not related with double strand break production. Furthermore, all these effects were not associated with oxidative damage production and, consequently, further investigations on the specific mechanisms underlying the effects observed in this study are required.
- Cytogenetic and immunological effects of formaldehyde in a group of exposed workersPublication . Costa, S.; García-Lestón, J.; Coelho, M.; Coelho, P.; Costa, C.; Silva, S.; Porto, B.; Laffon, B.; Teixeira, João PauloFormaldehyde (FA) is a widely used industrial chemical for which exposure is associated with nasopharyngeal and sinonasal cancer. Based on sufficient evidence of carcinogenicity from human investigations, supporting studies on mechanisms underlying carcinogenesis, and experimental evidence in animals, FA status was recently revised and reclassified as a human carcinogen. The highest level of exposure to FA occurs in occupational settings. Although several studies reported FA ability to induce genotoxic responses in exposed workers, not all findings were conclusive. In addition, published studies on the immunological effects of FA indicate that this compound may be able to modulate immune responses, although data in exposed subjects are still preliminary. In this study a group of pathology anatomy workers exposed to FA was evaluated for cytogenetic and immunological parameters. A control group with similar sociodemographic characteristics and without known occupational exposure to FA was also included. Genotoxicity was evaluated by means of micronucleus (MN) test, sister chromatid exchanges (SCE), and T-cell receptor (TCR) mutation assay. Percentages of different lymphocyte subpopulations were selected as immunotoxic biomarkers. The mean level of FA environmental exposure was 0.36 ± 0.03 ppm. MN and SCE frequencies were significantly increased in the exposed group. A significant decrease of the percentage of B cells in the exposed group was also found. Data obtained in this study indicate that genotoxic and immunotoxic increased risk due to FA occupational exposure cannot be excluded. Implementation of effective control measures along with hazard prevention campaigns may be crucial to decrease the risk.
- Cytotoxic effects of hydro-ethanolic extracts from Coleostephus myconis (L.) rchb.f. flowers and green partsPublication . Bessada, Silvia; Barreira, J.C.M.; Costa, C.; Bessa, M.J.; Teixeira, J.P.; Oliveira, M.B.P.P.The species Coleostephus myconis (L.) Rchb.f. is considered as being a harmful and persistent weed, with constant presence in abandoned farmland. Prevailing in the Portuguese flora, C. myconis belongs to the Asteraceae family, which is recognized for its global medicinal value and high antioxidant power, as described in different research works. Nevertheless, before considering incorporating this species in food of pharmaceutical applications, it is imperative to evaluate their potential toxicity.
- Cytotoxicity and antibacterial activity of polar extracts obtained from saffron (Crocus sativus L.) Floral bio-residuesPublication . Barreira, João; Costa, C.; Branquinho, R.; Rebelo, J.M.; Bessa, M.J.; Peixe, L.; Teixeira, J.P.; Oliveira, M.B.P.P.Saffron (Crocus sativus L.) flower comprises six purple tepals, three yellow stamens and a white filiform style ending in a stigma with three threads, which represents less than 10% (w/w) of the flower weight. However, the stigma is the dominant reason to farm/harvest saffron, since it represents the most valued spice (after being dried). Interesting large amounts of floral bio-residues are produced and wasted from this action, considering that a single kg of saffron spice generates ~63 kg of floral bioresidues. This scenario creates opportunities for the extended use of this discarded material, particularly owing to its important bioactive compounds and related health promoting properties, such as antioxidant, antityrosinase, antidepressant, antifungal, antinociceptive, anti-inflammatory and arterial pressure reduction.
- DNA damage and oxidative DNA damage in Inflammatory Bowel DiseasePublication . Pereira, C.; Coelho, R.; Grácio, G.; Dias, C.; Silva, M.; Peixoto, A.; Lopes, P.; Costa, C.; Teixeira, J.P.; Macedo, G.; Magro, F.