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- Use of urban groundwater for public lakes supply: terrestrial ecotoxicologial evaluationPublication . Santos, Vera; Oliveira, Filipa; Nunes, Mafalda; Borges, Luísa; Santos, R.; Barros, Piedade; Pereira, AnaThe correct management of water resources needs to be based on solid environmental information collected by monitoring programs and properly analyzed by well established methodologies.
- Evaluation of valproic acid toxicity in duckweed, Lemna minorPublication . Machado, Beatriz; Prudêncio, Cristina; Ferraz, Ricardo; Barros, PiedadeIn the last years the contamination of water caused by drugs has increased significantly. The main cause is the increase of the number and quantities of drugs that is being used. Many of these compounds cannot be removed effectively by wastewater treatment plants. This problem affects the water cycle and, consequently, all the environment as well as the human health, so it is important to find new methods that can help the removal of drugs from the water. This research is aimed to understand the influence of different concentrations of valproic acid on the growth of the duckweed Lemna minor. After 7 days of exposure it was analysed the number of fronds, the length of the root and the chlorophylls content. The chlorophylls of the Lemna minor samples were analysed by spectrophotometry. The number of fronds was influenced by the concentration of valproic acid. The higher concentrations (0,1 mg/mL; 0,05 mg/mL; 0,025 mg/mL) showed an inhibitory effect while the lower concentrations (0,005 mg/mL; 0,0001 mg/mL) showed a stimulating effect. Relative to the control, the number of fronds was lower in the higher concentrations and higher in the lower concentrations. The root length was affected in all the concentrations. Comparative to the control the higher concentrations presented a diminution of the root’s length while the higher ones had an increase. Like the other parameters the concentration of chlorophylls was affected in all the samples. In the higher concentrations (0,1 mg/mL; 0,05 mg/mL; 0,025 mg/mL) the quantity was lower, comparatively to the control, and in the lower ones (0,01 mg/mL; 0,005 mg/mL; 0,0001 mg/mL) it was higher. In general, the valproic acid influenced all the parameters evaluated: number of fronds, length of the root and concentration of chlorophylls. In the higher concentrations it is notable an inhibitory effect while the lower concentrations have a stimulating one.
- Ecotoxicological evaluation of Pentachlorophenol in Avena sativa L. e Glycine max L.Publication . Pina, Ana; Nunes, Mafalda; Barros, PiedadePentachlorophenol (PCP) is the largest chlorinated compound from chlorophenols family and it is included in the list of priority pollutants from the US Environmental Protection Agency (EPA) and the European Union, due to its persistence and high toxicity. It was used mainly as a wood preservative; in fungicidal and insecticidal solutions and for incorporation into other pesticide products.
- New technologies in health education and researchPublication . Juanes, Juan A.; Ruisoto, Pablo; Barros, PiedadeThe studies in this track provided an updated overview of different technological innovation procedures in distinct health science fields. Thus, technological applications from medical imaging treatment and three-dimensional visualization to simulation systems useful in clinical practice training (simulations with mannequins, training with manual control devices, virtual reality techniques with stereo vision helmets, amongst others) are presented. The main objective of these procedures is to improve the quality of university teaching and continuing education, using the latest resources, which are starting to be implemented in different universities.
- Toxicity of formaldehyde alternative fixatives to ecological model organismsPublication . Barros, Piedade; Silva, ReginaFixation is a fundamental and critical step in the preparation of tissue specimens for histological study since, if it is carried out under non optimal conditions, irreversible damage can occur and subsequent information obtainable from the specimen is compromised. Formaldehyde is the most common fixative in histology but due to its occupational and environmental toxicity, formalin substitute’s fixatives have been developed. The toxic evaluations of these fixatives to environmental key species are still poorly studied.
- Effects of low doses of external radiation from 137Cs on Lactuca sativa seedling and Daphnia magna reproductionPublication . Teles, Luís; Henriques, Marta; Santos, Rubim; Barros, PiedadeNaturally occurring cesium exists as a stable isotope 133Cs in the earth crust in granites and in sedimentary rocks. Cesium has very low mobility in soil surfaces.
- Merging new technologies with health sciences education and practicePublication . Juanes, Juan A.; Ruisoto, Pablo; Barros, PiedadeThe aim of this track is to collect some of the most innovative computer based technological developments applied to both the contexts of biomedical training and clinical practice, as well as in other fields related to Health Sciences training, providing an excellent opportunity for the promotion and exchange of innovative teaching experiences in the health field, especially those based on the use of state-of-the-art technology.
- Elucidating the mechanisms Involved in the cytotoxicity induced by marine cyanobacteria strains against the RKO colon carcinoma cell linePublication . Freitas, S.; Urbatzka, R.; Osório, H.; Costa, M.; Barros, Piedade; Vasconcelos, V.; Martins, RosárioCyanobacteria are known to synthesize secondary metabolites that may have potential as drugs for the treatment of human diseases such as cancer. Previous studies on marine cyanobacteria isolated from the Portuguese coast revealed strains of the picoplanktonic genera Cyanobium and Synechocystis as potential sources of anticancer compounds. The ethyl acetate fraction of the strains Cyanobium sp. LEGE06113 and the Synechocystis salina LEGE06155 was found to reduce cell viability of cancer cell lines. This work aimed to elucidate the mechanisms involved in the cytotoxicity of this strains in the colon adenocarcinoma cell line RKO by employing real-time PCR (RT-PCR) for genes involved in cell cycle and apoptosis, by flow cytometry for cell cycle and by two-dimensional gel electrophoresis for protein expression. RT-PCR results revealed differences in mRNA expression of genes CCNB1 (cell cycle) and BCL-2 (apoptosis). Flow cytometry results revealed a decrease in the G0/G1 and S phase and increased its number in the G2/M phase, which is in accordance with the lower expression of CCNB1. The proteomic results demonstrated different protein patterns comparing treatment groups with control. Proteins differentially regulated in exposed RKO cells were involved in cell cycle regulation, apoptosis, cell structure, protein regulation and cell metabolism. Although several of these proteins were identified in cells exposed to both cyanobacterial extracts, the data provides an indication that the cytotoxicity is induced by different toxic mechanisms in LEGE06113 and LEGE06155 fractions.
- Toxicity of pentachlorophenol on the reproductive cycle of Eisenia fetidaPublication . Oliveira, Ana; Barros, Piedade; Nunes, MafaldaPentachlorophenol (PCP) in the environment can largely be attributed to contamination of sediments from historic usage, since nowadays the use of PCP is restricted. The soil accommodates a huge amount of organisms and is a very important resource because it is the basis for farming, which allows obtaining food. The organisms present in the soil are part of the basic trophic levels in the food chain and maintain the soil fertile. A very important organism for soil fertility is the earthworm because it’s responsible for the improvement of the soil structure, decomposition of organic matter, mineralization of nutrients and its diffusion to the plants. The earthworm Eisenia fetida is used on toxicity tests because of its susceptibility to chemicals and its short life cycle.
- Evaluating the effect of the Ionic liquid [C16Pyr] [Amp] in hormone-resistant tumors using an in vivo zebrafish assayPublication . Barros, Piedade; Martins, Rosário; Cruz, Agostinho; Silva, ReginaThe NASYTHOR project, aimes to study the potential of novel natural and synthetic compounds as anti-cancer drugs on hormone-resistant tumors. One of the objectives is the evaluation of the in vivo efficacy of the anticancer activity of the compounds using Danio rerio, zebrafish embryo as a model. In this work we describe the general methodology, advantages and disadvantages. Among a large range of advantages in the use of zebrafish in cancer research, the high level of genetic and physiologic homology with humans, including brain, digestive tract, musculature and vasculature can be highlighted. Also, the immature immune system of the embryos favors xenotransplantation of human cancer cells, and makes these animals a promising experimental model to tumorigenesis, angiogenesis, invasion and metastasis. The ionic liquid cetylpyridinium ampicillin [C16Pyr] [Amp] induces cytotoxicity in hormone-resistant breast and prostate cancer cell lines. To study the possible use of [C16Pyr] [Amp] as an anticancer, the toxicity towards zebrafish embryos should be evaluated first by an acute toxic assay that should be carried out following the OECD 236 Guideline.