Browsing by Issue Date, starting with "2014-07"
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- Aspergillus flavus contamination in 2 Portuguese waste water treatment plants: an occupational threatPublication . Viegas, C.; Dias, R.; Gomes, A.Q.; Meneses, M.; Sabino, R.; Viegas, S.Filamentous fungi from genus Aspergillus were previously detected in wastewater treatment plants (WWTP) as being Aspergillus flavus (A. flavus), an important toxigenic fungus producing aflatoxins. This study aimed to determine occupational exposure adverse effects due to fungal contamination produced by A. flavus complex in two Portuguese WWTP using conventional and molecular methodologies. Air samples from two WWTP were collected at 1 m height through impaction method. Surface samples were collected by swabbing surfaces of the same indoor sites. After counting A. flavus and identification, detection of aflatoxin production was ensured through inoculation of seven inoculates in coconut-milk agar. Plates were examined under long-wave ultraviolet (UV; 365 nm) illumination to search for the presence of fluorescence in the growing colonies. To apply molecular methods, air samples were also collected using the impinger method. Samples were collected and collection liquid was subsequently used for DNA extraction. Molecular identification of A. flavus was achieved by real-time polymerase chain reaction (RT-PCR) using the Rotor-Gene 6000 qPCR detection system (Corbett). Among the Aspergillus genus, the species that were more abundant in air samples from both WWTP were Aspergillus versicolor (38%), Aspergillus candidus (29.1%), and Aspergillus sydowii (12.7%). However, the most commonly species found on surfaces were A. flavus (47.3%), Aspergillus fumigatus (34.4%), and Aspergillus sydowii (10.8%). Aspergillus flavus isolates that were inoculated in coconut agar medium were not identified as toxigenic strains and were not detected by RT-PCR in any of the analyzed samples from both plants. Data in this study indicate the need for monitoring fungal contamination in this setting. Although toxigenic strains were not detected from A. flavus complex, one cannot disregard the eventual presence and potential toxicity of aflatoxins.
- Guia orientativo para o estabelecimento de porções para a rotulagem nutricionalPublication . Brazão, Roberto; Dias, M. Graça; Oliveira, Luísa; Dias, CatarinaO “Guia Orientativo para o Estabelecimento de Porções para a Rotulagem Nutricional” tem por objetivo estabelecer um conjunto de orientações com vista a uniformizar a indicação da porção como unidade para a apresentação voluntária da informação nutricional nos rótulos dos géneros alimentícios. Este documento foi desenvolvido pelo Grupo de Trabalho Porções (GTP), no âmbito do Programa PortFIR - Plataforma Portuguesa de Informação Alimentar.
- Association between alcohol and cardiovascular disease: Mendelian randomisation analysis based on individual participant dataPublication . Holmes, M.V.; Dale, C.E.; Zuccolo, L.; et al.; InterAct ConsortiumTo use the rs1229984 variant in the alcohol dehydrogenase 1B gene (ADH1B) as an instrument to investigate the causal role of alcohol in cardiovascular disease. DESIGN: Mendelian randomisation meta-analysis of 56 epidemiological studies.
- Variation of DNA damage levels in peripheral blood mononuclear cells isolated in different laboratoriesPublication . Godschalk, R.W.; Ersson, C.; Stępnik, M.; Ferlińska, M.; Palus, J.; Teixeira, João Paulo; Costa, S.; Jones, G.D.; Higgins, J.A.; Kain, J.; Möller, L.; Forchhammer, L.; Loft, S.; Lorenzo, Y.; Collins, A.R.; van Schooten, F.J.; Laffon, B.; Valdiglesias, V.; Cooke, M.; Mistry, V.; Karbaschi, M.; Phillips, D.H.; Sozeri, O.; Routledge, M.N.; Nelson-Smith, K.; Riso, P.; Porrini, M.; López de Cerain, A.; Azqueta, A.; Matullo, G.; Allione, A.; Møller, P.This study investigated the levels of DNA strand breaks and formamidopyrimidine DNA glycosylase (FPG) sensitive sites, as assessed by the comet assay, in peripheral blood mononuclear cells (PBMC) from healthy women from five different countries in Europe. The laboratory in each country (referred to as 'centre') collected and cryopreserved PBMC samples from three donors, using a standardised cell isolation protocol. The samples were analysed in 13 different laboratories for DNA damage, which is measured by the comet assay. The study aim was to assess variation in DNA damage in PBMC samples that were collected in the same way and processed using the same blood isolation procedure. The inter-laboratory variation was the prominent contributor to the overall variation. The inter-laboratory coefficient of variation decreased for both DNA strand breaks (from 68 to 26%) and FPG sensitive sites (from 57 to 12%) by standardisation of the primary comet assay endpoint with calibration curve samples. The level of DNA strand breaks in the samples from two of the centres (0.56-0.61 lesions/10(6) bp) was significantly higher compared with the other three centres (0.41-0.45 lesions/10(6) bp). In contrast, there was no difference between the levels of FPG sensitive sites in PBMC samples from healthy donors in the different centres (0.41-0.52 lesion/10(6) bp).
- Integrated approach to the in vivo genotoxic effects of a titanium dioxide nanomaterial using LacZ plasmid-based transgenic micePublication . Louro, Henriqueta; Tavares, Ana; Vital, Nadia; Costa, Pedro M.; Alverca, Elsa; Zwart, Edwin; de Jong, Wim H.; Féssard, Valerie; Lavinha, João; Silva, Maria JoãoTitanium dioxide (TiO2 ) nanomaterials (NMs) are widely used in a diversity of products including cosmetics, pharmaceuticals, food, and inks, despite uncertainties surrounding the potential health risks that they pose to humans and the environment. Previous studies on the genotoxicity of TiO2 have reported discrepant or inconclusive findings in both in vitro and in vivo systems. This study explores the in vivo genotoxic potential of a well-characterized uncoated TiO2 NM with an average diameter of 22 nm (NM-102, from JRC repository) using several genotoxicity endpoints in the LacZ plasmid-based transgenic mouse model. Mice were exposed by intravenous injection to two daily doses of NM-102: 10 and 15 mg/kg of body weight/day. Micronuclei were analyzed in peripheral blood reticulocytes 42 hr after the last treatment. DNA strand breaks (comet assay) and gene mutations were determined in the spleens and livers of the same animals 28 days after the last treatment. Histopathological and cytological analyses were also performed in liver samples. Genotoxic effects were not detected in mice exposed to the nanosized TiO2 under the experimental conditions used, despite a moderate inflammatory response that was observed in the liver. Considering the biopersistence of TiO2 in mouse liver and the moderate inflammatory response, the possibility of a secondary genotoxic effect at higher doses and in conditions that result in a stronger inflammatory response, for example, within a longer time window, should be investigated further.
- Molecular screening of 246 Portuguese Aspergillus isolates among different clinical and environmental sourcesPublication . Sabino, R.; Veríssimo, C.; Parada, H.; Brandão, João; Viegas, C.; Carolino, E.; Clemons, K.V.; Stevens, D.A.Clinical and environmental samples from Portugal were screened for the presence of Aspergillus and the distribution of the different species-complexes determined to understand differences in their distribution from different sources. Fifty-seven Aspergillus isolates from clinical samples were collected from 10 health institutions. Six species-complexes were detected by ITS sequencing: Fumigati, Flavi, and Nigri were the most frequent (50.9%, 21.0% and 15.8%, respectively). β-tubulin and calmodulin sequencing resulted in seven cryptic species (A. awamorii, A. brasiliensis, A. fructus, A. lentulus, A. sydowii, A. tubigensis, and Emmericella echinulata) being identified among the 57 isolates. Thirty-nine isolates of Aspergillus were recovered from beach sand and poultries, 31 from swineries, and 80 from hospital environments, for a total 189 isolates. Eleven species-complexes were found in these 189 isolates, and those belonging to the Versicolores species-complex were found the most frequently (23.8%). There was a significant association between the different environmental sources and the distribution of the several species-complexes; the hospital environment had greater variability of species-complexes than other environmental locations. A high prevalence of cryptic species within Circumdati complex was detected in several environments and from the isolates analyzed, at least four cryptic species were identified, most of them growing at 37ºC. Because Aspergillus species-complexes have different susceptibilities to antifungals, knowing the species-complex epidemiology for each setting, as well as the identification of cryptic species among the collected clinical isolates is important. This may allow preventive or corrective measures to be taken, which may result in decreased exposure to those organisms and a better prognosis.
- Nowcasting daily mortality on real-time for public health surveillancePublication . Antunes, Liliana; Antunes, Marília; Nunes, BaltazarIt is well described in the literature that during health-related events, like influenza epidemics or occurrence of extreme weather events, such as heat waves or cold spells, the observed “all causes” mortality increases above the expected, presenting excess deaths of 20-40%.These facts have triggered the development of Public Health surveillance systems, with the objective of early detection of such events, so that public health measures can be taken in time, as well the estimation of its impact. Since the 2003 heat wave, the Department of Epidemiology of INSA has been developing a daily mortality monitoring system (VDM), which came fully operational in 2007. In this system INSA receives electronically, on a daily basis, all deaths registered in the previous day at the Conservatories of the Civil Registry. Previous studies have showed that 95% of the deaths that occurred in specific day are registered up to 6 days after, with an average and median delay of 8 and 2 days respectively. Given that the detection of the impact of the events are dependent on these delays, it would be very important to have, on a daily basis, the estimate of the number of deaths occurred but not yet registered in the system.
- Microarray em Diagnóstico Pré-NatalPublication . Correia, Hildeberto
- Development of an orange juice in-house reference material and its application to guarantee the quality of vitamin C determination in fruits, juices and fruit pulpsPublication . Valente, A.; Sanches-Silva, A.; Albuquerque, T.G.; Costa, H.S.Reference materials are useful for the quality control of analytical procedures and to evaluate the performance of laboratories. There are few and expensive certified reference materials commercially available for vitamin C or ascorbic acid analysis in food matrices. In this study, the preparation and the suitability assessment of an orange juice in-house reference material (RM) for vitamin C analysis in fruits, juices and in fruit pulps is described. This RM was used for the development and full validation of an HPLC method. The results showed excellent linearity (r2 = 0.9995), good accuracy (96.6–97.3%) and precision, as relative standard deviation, ranged from 0.70% to 3.67%. The in-house RM was homogenous and stable at storage conditions (−80 °C) during 12 months. According to our results, this in-house RM is an excellent tool to use in quality control and method verification purposes for vitamin C analysis of fruits, juices and fruit pulps matrices. Furthermore, a stabilization solution with perchloric and metaphosphoric acids was developed which prevents degradation of ascorbic acid for a period of 12 months at −80 °C.
- Amianto nos Edifícios - Avaliação da ExposiçãoPublication . Proença, Maria do CarmoTópicos: - Amianto: propriedades, aplicações e riscos para a saúde; - Localização nos edifícios; - Legislação aplicável – profissionais em riscos; - Avaliação do risco em função do tipo de aplicação, estado de conservação e acessibilidade do MCA; - Metodologia de análise: materiais e ar ambiente.