Browsing by Issue Date, starting with "2016-09"
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- Ocorrência de micotoxinas em alimentos para crianças comercializados em PortugalPublication . Martins, Carla; Assunção, Ricardo; Pires, M.J.; Cunha, S.; Petta, T.; Jagger, A.; Oliveira, C..; Alvito, PaulaMicotoxinas - características gerais: - são metabolitos secundários produzidos por fungos, capazes de produzir efeitos tóxicos agudos e crónicos (carcinogénicos, mutagénicos, teratogénicos, imunotóxicos e estrogénicos), em animais e humanos; - Os alimentos são susceptíveis à contaminação nas diferentes fases da colheita, produção, armazenamento ou processamento.
- NANoREG Project (GA 310584). Progress reportPublication . Maria João Silva, Henriqueta LouroThe toxicity of NMs in submerged conditions with the alveolar cell line A549 was finalized, concerning the four selected nanomaterials (NMs): TiO2 (NM-100 and NM-1001), CeO2 (NM-2102) and BaSO4 (NM-220). Cytotoxicity was analysed using the MTT assay and the colony forming efficiency assay (CFE or clonogenic assay). The alkaline comet plus the FPG-modified assays and the cytokynesis-blocked micronucleus assay were used to address the genotoxic effects. The tests were performed with A549 cells cultured in conventional submerged cultures. Following the recommendation of the guidance document, the quality of the NM batch dispersion, as well as that of the NM dilution in the complete cells exposure medium, were analyzed using dynamic light scattering (DLS) performed shortly after dispersion and after incubation during 24h, 72h and 7 days. Most of the batch dispersions were in similar size range of the NANoREG benchmark data. In general, the dilution of the batch in cell culture medium showed no major impact on NM sizes and, after 24h incubation, sedimentation of the NMs probably contributed to the observation of lower size dispersed NMs when analyzing the suspension by DLS. The CFE assay with A549 cells was used to assess the cytotoxicity of a set of NMs that were agreed upon with NILU to allow data comparison between the two laboratories. Two alternative methods were used to perform the assay – exposure of cells at a high desnsity to the NM (24h) or exposure of a small number of adherent cells to the NM during 7 days – and the following NMs were tested: silver NMs (NM-300k and NM-302) as well as zinc oxide (NM-110), amorphous silicon dioxide (NM-2000 and NM-203), a multiwalled carbon nanotube (NM-401) and titanium dioxide (NM-103). Also, within a collaborative work with NILU aimed at characterizing the genotoxicity of three metallic NMs using regulatory tests (the hprt mutation assay, the comet assay and the micronucleus assay) results from the micronucleus assay in V79 cells were obtained for NM-100, NM-302 and NM-2102. All results were analyzed using adequate statistical tools. All data have been uploaded into the NanoReg Database entry tool with the exception of CFE for which no model database has been produced. The later data will be sent to the task leaders in order to be uploaded at CIRCABC.
- Salt content of processed foods available in the Portuguese marketPublication . Albuquerque, T.G.; Oliveira, M.B.; Silva, M.A.; Costa, H.S.Evidence suggests that current levels of salt consumption across Europe are linked with several chronic diseases. In recent decades, high blood pressure has increased, together with the consumption of processed foods. World Health Organization (WHO) recommends a salt intake of less than 5 g/day for the prevention of cardiovascular disease. The aim of this study was to evaluate the salt content of processed foods available in the Portuguese market and to compare the determined values with the recommended daily intake established by WHO. Categories of processed foods that contribute to a higher intake of salt were identified: pastry, bakery, fast-food, snacks, ready-to-eat meals, nuts, seeds, soups, cereals, sauces, patties, among others. Between 2013 and 2015, 267 processed food samples were acquired in food chains and restaurants from Lisbon region (Portugal) and the salt content was quantified using Charpentier-Volhard method. High amounts of salt were quantified in the analysed processed foods, namely snacks, fast-food, patties, meals and bakery products. If we consider one portion of a curd cheese pie (193 g), the intake of salt can reach 45% of the recommended value. For snacks, regular portion size is 35 g. One portion of a salty snack can contribute with 31% of the salt recommended daily intake. Up to now food industry has developed efforts to decrease the salt content of some food products, namely bread. However, there still exist foods with high salt content and from a nutritional point of view this should be a priority area of intervention. The obtained results are an effective assessment of current salt content in foods which will be important for further reformulation strategies and to monitor progress in the next years.
- Occurrence of Trihalomethanes in Chlorinated Waters from Different Sources Used for Urban SupplyPublication . Melo, Armindo; Mansilha, Catarina; Margarida, Teixeira; Ferreira, Isabel M.P.L.V.O.Trihalomethanes (THMs) are the most common disinfection by-products formed by the reaction of chlorine and/or bromide with organic matter. Total THMs in chlorinated treated water are defined as the sum of the concentrations of chloroform (TCM), bromodichloromethane (BDCM), dibromochloromethane (DBCM), and bromoform (TBM). The monitoring of trihalomethanes in distribution tap water collected in from five regions of Portugal, from North to South, in a total of 33 samples, during spring to summer season, is described. Solid phase microextraction coupled to gas chromatography and electron capture detector methodology was applied to determine whether THMs concentrations in urban water supply systems are is in agreement with European Regulations. It was found a great discrepancy in total THMs concentration values, with concentrations varying from 1.8-97.7 μg/L, although the results were below the European parametric value of 100 μg/L. Regarding the Environmental Protection Agency regulations, however, only 97% of samples fulfilled the established criterion of 80 μg/L. and investigate if the individual compounds trihalomethanes content in was also investigated in order to determine if there is observed distribution tap water follows a common or a different THMs pattern in close geographical areas. In the geographical areas under study, mean values of concentrations measured revealed two different clusters: one including the three groups from the North geographical areas, with samples revealing a similar pattern (TCM>BDCM>DBCM>TBM), and another including the two groups from South with a different THMs pattern (DBCM>BDCM>TCM>TBM). A great degree of variation in the concentrations of THMs in tap water was observed, although the results the total THMs concentrations were below the European parametric value (100 μg/L). Mean results of samples grouped by five geographical areas revealed a similar pattern in samples collected from North and Centre TCM>BDCM>DBCM>TBM, whereas samples from South presented a different pattern, DBCM>BDCM>TCM>TBM. The origin of raw water (surface or groundwater) seems to influence this different pattern formation of brominated compounds.
- Atividade antioxidante, fenólicos totais, flavonóides totais e vitaminas em subprodutos de anonaPublication . Albuquerque, T.G.; Oliveira, M.B.; Santos, F.; Costa, H.S.A anona é um fruto muito apreciado pelas suas características organoléticas distintas, nomeadamente textura e sabor. Desde 2000, a anona da Madeira foi registada com Denominação de Origem Protegida. Depois da banana, é o fruto mais exportado na Região Autónoma da Madeira. Hoje em dia, a valorização de resíduos e de subprodutos agroalimentares tornou-se uma necessidade, sobretudo quando é possível utilizar estes subprodutos para o desenvolvimento e conceção de novos produtos. O objetivo deste trabalho foi avaliar a atividade antioxidante, teor de fenólicos e de flavonóides totais e os teores das vitaminas C e E em subprodutos de três cultivares de anona (Madeira, Mateus II e Perry Vidal). As amostras de Annona cherimola Mill. foram colhidas em diversos locais da Região Autónoma da Madeira. Posteriormente, as amostras foram separadas em polpa, casca e semente e procedeu-se à determinação dos parâmetros analíticos. Os extratos da casca e da semente para avaliação da atividade antioxidante, fenólicos totais e flavonóides totais, foram preparados em etanol (90%, v/v). Para avaliação da atividade antioxidante, utilizou-se o método do DPPH•, e os resultados foram expressos em EC50. O teor de fenólicos totais foi determinado pelo método de Folin-Ciocalteu e os resultados foram expressos em equivalentes de ácido gálhico. Os resultados referentes aos flavonóides totais foram expressos em equivalentes de epicatequina. Para a determinação das vitaminas utilizou-se a cromatografia líquida com deteção por díodos. A maior atividade antioxidante foi determinada na casca da anona do cultivar Madeira e a menor nas sementes da anona do cultivar Perry Vidal. O teor de fenólicos totais e de flavonóides totais também foi superior na casca comparativamente à semente dos diferentes cultivares analisados. O teor de vitamina C total variou entre 1,54 ± 0,1 (semente) e 5,17 ± 0,1 mg/100 g (casca), para o cultivar Perry Vidal. O teor de vitamina E (α-tocoferol) mais elevado foi determinado para a semente do cultivar Mateus II (1,1 ± 0,07 mg/100 g). Os resultados obtidos demonstram o potencial antioxidante dos subprodutos da anona da Madeira, sobretudo a casca, podendo constituir desta forma uma fonte natural de extratos de valor acrescentado com aplicações em inúmeras indústrias, nomeadamente a alimentar, farmacêutica e/ou cosmética.
- Prevalence of Autism Spectrum Disorder in the central region of PortugalPublication . Vicente, Astrid
- Helicobacter pylori strains from ulcer and non-ulcer differ in binding ability to mucinsPublication . Quintana-Hayashi, M.P.; Rocha, R.; Roxo-Rosa, M.; Oleastro, M.; Linden, S.K.Background : Adhesion to mucins within the mucus layer and to membrane bound mucins present on the surface epithelial cells is a key step in the interacon of H. pylori and its host. Aim : To invesgate the level and mechanisms of binding of non- ulcer dyspepsia (NUD) strains versus pepc ulcer disease (PUD) strains to human gastric mucins.
- Pollution of alpine ponds and groundwater by de-icing chemicals (Serra da Estrela, Central Portugal)Publication . Mansilha, Catarina; Marques, Jorge; Paiva, MarinaThe ecological and socioeconomic importance of mountains is being increasingly recognised. Such regions provide key ecosystem services, namely, water supply which benefits local as well as lowland human populations. Besides mountain aqui fers and rivers, alpine lakes and ponds are crucial for water resources management but are also important in hydroecological and wildli fe conservation terms. This study aims at comparing the pollution of surface and underground water bodies by de -icing chemicals in a mountain environment. The influence of geological, geomorphological, pedological, climatic and anthropic conditions is taken into account. The study region is the highest part of the Serra da Estrela, a Mediterranean mountain located in Central Portugal. In this area there is a hydrological system which encompasses water-table aquifers and number of alpine ponds of glacial origin situated between 1500 m a.s.l. and the summit (1993 m a.s.l.). In the study area, the alpine ponds and springs were inventoried. Water sampling campaigns were carried out for hydrogeochemical characterisation of alpine ponds. These results were compared with hydrogeochemical data from water springs obtained in previous studies. Concentration of the following analytes were determined- total organic carbon (TOC), metals (Pb, Zn, Fe, Cu, Ni, Cd, Cr, As, Mn), cations (Na+, K+, Ca2+, Mg2+), anions (F-, CI-, NO3-, SO42-), silica (SiO2) and nutrients (N, P). Additionally, parameters such as pH, conductivity, turbidity and alkalinity were also measured. The hydrogeochemistry of ponds and water table aqui fers affected by de-icing chemicals is clearly different from the one showed by non-polluted water bodies, due to the influence of different physical settings as well as to the spatial distribution of the anthropic influence. The pond and aqui fer contamination affects water quality but may also disturb the local highly sensitive aquatic ecosystems.
- Zika virus infections imported to Portugal, the National Reference Laboratory experience: The importance of sample collection time lapse in diagnosisPublication . Zé-Zé, L.M.; Alves, M.J.Zika virus (ZIKV) belongs to the genus Flavivirus and was first isolated from the blood of a febrile sentinel rhesus monkey during a study of yellow fever in 1947, in Zika Forest, Uganda. ZIKV is transmitted by Aedes sp. Mosquitoes, as Dengue, Yellow fever and Chikungunya viruses, and was until recently considered a mild pathogenic mosquito-borne flavivirus with very few reported human cases of self-limiting acute febrile illnesses most often with maculopapular rash, headache, malaise and conjunctivitis, all followed by full recovery without sequel. During 60 years, cases of ZIKV infections were detected only sporadically in Africa, and South and Southeast Asia. (...)
- Evaluation of the antiviral activity of an aqueous extract from Solidago virgaurea against Herpes simplex virus type 2Publication . Mendes, Ana Rita; Lopo, Sílvia; Ascensão, Lia; Falé, Pedro; Serralheiro, Luisa; Caeiro, Maria FilomenaHerpes simplex virus type 2 (HSV-2) is widely distributed through the human population, infecting more than 500 million people globally [1]. Although typically causing mild diseases this virus may be responsible for severe infections, mainly in immunocompromised patients. Currently, there is a number of systemic antiviral agents against herpesvirus, the most commonly used being acyclovir and related drugs. However, long term treatments with these drugs may result in the development of resistance, especially in immunocompromised patients, which leads to a continuous search for new and better therapeutic alternatives [2]. According to the World Health Organization plants are the best sources for obtaining a wide variety of drugs [3]. So, in the last decades many pharmacological and chemical studies have focused on medicinal plants to the discovery of new natural antiviral compounds.