DEP - Apresentações orais em encontros internacionais
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- Occurrence and infant exposure assessment of chemical contaminants in baby foodsPublication . Alvito, Paula; Vasco, Elsa; Martins, Carla; Paixão, Eleonora; Calhau, Maria Antónia
- Genotoxicidade da MCLR em vários modelos biológicos: linhas celulares, eritrócitos de murganho e linfócitos humanosPublication . Dias, Elsa; Louro, Henriqueta; Pereira, Paulo; Silva, Maria JoãoO conhecimento sobre as propriedades toxicológicas das microcistinas é ainda bastante limitado, em particular no que respeita à sua actividade cancerígena. É globalmente aceite que as microcistinas são promotores tumorais, mas é ainda ambígua a sua eventual genotoxicidade. Alguns autores defendem que as microcistinas são genotóxicas e que induzem quebras no ADN, outros defendem que as microcistinas não são genotóxicas. Alguns destes resultados são dificilmente comparáveis porque foram obtidos através de metodologias distintas, nomeadamente no que respeita ao tipo de toxina usado, ao modelo celular testado e ao método para avaliação de efeito genotóxico aplicado. A nossa equipa tem vindo a estudar as propriedades genotóxicas da MCLR em diversos modelos biológicos: linha celular Vero-E6 (rim de macaco), linha celular HepG2 (hepatoma humano) e eritrócitos de murganho. Para tal temos usado dois tipos de abordagem metodológica: o Teste do Cometa, que avalia danos ao nível da cadeia de ADN, e o Ensaio do Micronúcleo, que avalia a actividade clastogénica (quebra cromossómica) ou aneugénica (perda de cromossomas). Naqueles modelos demonstrámos que a MCLR não induz danos no ADN pelo teste do Cometa mas induz o aumento da frequência de micronúcleos in vitro e in vivo. Nesta apresentação iremos discutir os nossos resultados mais recentes acerca do efeito da MCLR na indução de micronúcleos em linfócitos humanos e comparar com os resultados publicados por outros autores. Iremos também discutir o mecanismo de acção genotóxica da MCLR e a sua importância para a avaliação do risco de exposição humana a água contaminada com cianobactérias produtoras de microcistinas.
- Injury Surveillance in PortugalPublication . Contreiras, Teresa
- Risk assessment in an estuarine environment: a case-study in the Sado EstuaryPublication . Machado, Ausenda; Paixão, Eleonora; Caeiro, Sandra; Dias, Carlos MatiasIntroduction Previous studies found high heavy metal concentration on Sado estuary, its sediments and marine species, related with industrial and non-point anthropogenic sources. Heavy metal human exposure is associated with neoplasic, renal and neurological diseases, as well as teratogenic effects, but has never been assessed in populations living on this estuary. The HERA project (Environmental Risk Assessment of a contaminated estuarine environment: a case study) aimed to characterize human exposure pathways and potential health effects of estuarine contamination. Materials and Method The cross-sectional epidemiological study compared the population of a small fisherman community (Carrasqueira) on the southern shore of the Sado Estuary, with a non exposed population living in Vila Nova de Mil Fontes (VNMF). Face to face data collection took place between June and July 2011 using a structured questionnaire. Participants were selected by simple randomization of medical registration lists of local Health Centers. Written informed consent was obtained. Identification of potential confounders and adjusted OR were computed using Mantel-Haenszel and non-conditional logistic regression. Significance level was set at 5%. Results Results relate to 202 participants. Carrasqueira population showed a significantly higher risk of exposure from several sources (occupation, leisure habits, estuarine fish consumption, estuarine water for drinking, food preparation, irrigation, as well as own grown vegetable consumption). A higher proportion of chronic heavy metal related morbidity (OR= 1,913; IC95%: 1,007-3,635), and congenital anomalies (OR= 1,527; IC95%: 0,474- 4,918) were observed in Carrasqueira. Only age was retained as confounder in logistic regression, resulting in a 2,361 higher risk of having at least one of the diseases in Carrasqueira compared to VNMF (IC95%: 1,189-4,691). Conclusions These results support possible health effects of exposure to Sado estuary. However, small sample size and self-reported nature of exposure and outcomes advice caution in interpretation. Further studies should use bioindicators of exposure and outcome.
- Occupational exposure in a contaminated estuarine environment epidemiological studyPublication . Paixão, Eleonora; Machado, Ausenda; Caeiro, Sandra; Dias, Carlos MatiasIntroduction: Previous environmental studies on Sado estuary indicated high concentrations of heavy metals (such as Cu, Zn, Ni, As, Cr, e Pb) on its sediments due to industrial contamination along with non-point anthropogenic sources. Although considerable investigation has been done on environmental contamination assessment and its effects to ecological systems, in this particular geographical area no study relating the health effects due to exposure to heavy metals was ever conducted. Thus an epidemiological study, was implemented in a small fisherman community living in Carrasqueira Village at Sado Estuary (exposed population) and in Vila Nova de Mil Fontes- VNMF (non exposed).The results to be presented reflect the analysis of occupational exposure comparing both populations. Material and Methods: A cross-sectional study was designed and data was collected through an epidemiological questionnaire. Face to face interviews of selected individuals was done during June and July 2011. Participants, from all ages and sex, were selected by simple randomization, using the medical registrations lists of local Health Centers. Dimensions measured in the two groups included among others i) Exposure factors related to levels of contaminants, including socio-demographic, occupational, leisure habits and hobbies, ii) Route of contamination (with special attention to subsistence fishing and farming) and iii) Health effects. To each respondent was required to describe the tasks inherent to their actual or past job. From this description indicators of a potential route exposure to contaminants were created. It was considered direct exposure (fishing inherent tasks); indirect exposure (agriculture inherent tasks), other routes of contamination (tasks with other sources of contamination such as painting). The absence of the previous exposures indicates that no relevant exposure existed. Statistical analysis was performed using descriptive analysis and associations were tested using Chi-squared test. A 5% significance level was used in all the tests. Results: A total of 202 participants were included in the study (102 in Carrasqueira and 100 in VNMF) and no significant differences were observed in age distribution (p=0.267), but there were significant differences in the educational (p<0.001) level and occupation (p<0.001). Professions like fishers and agricultures are more likely to have higher risks of exposure to estuary river contaminants and were more common in Carrasqueira. The participants of Carrasqueira reported a significant higher proportion of tasks inherent to their actual job, promoting direct (48.8%) and/or indirect (30.0%) exposure to contaminants (p<0.001 and p=0.006 respectively). There were no differences in the other routes of contamination (p=0.511). On the opposite VNMF participants were not exposed to any contaminant route. Similar results were found in the analysis of tasks in previous professions. Also the period of time that was spent in the fishers and agricultures activities in Carrasqueira was higher than in VNMF (about 90% of individuals had more than 8 years of exposure, p<0.001). Conclusions: On exposure epidemiological studies the selection of non exposed population is critical to avoid bias. The results obtained showed that VNMF population was a good selection since they differ from Carrasqueira in the exposure indicators.
- Patterns and trends of tobacco consumption in the Portuguese population: National Health Survey data 1987 - 2005Publication . Leite, Andreia; Machado, Ausenda; Dias, Carlos MatiasBackground: Smoking is a significant risk factor for many diseases, particularly respiratory, cardiovascular and cancer. Describing smoking patterns in the Portuguese population is important for monitoring and planning preventative strategies for this public health problem. This study aims to contribute to the epidemiological survey of smoking in Portugal using data from the several National Health Surveys. Objectives: Estimate prevalence of smoking and its evolution from 1987 to 2005 according to socio-demographic characteristics. Methods: We used data collected in National Health Surveys 1987, 1995, 1998 and 2005. For each survey, gender specific smoking prevalences were computed for different age-groups. Also, age-standardized prevalences were estimated (direct method, standard European population), stratified by occupation, educational degree, professional category, marital status and region. Results: Smoking prevalences suggest cohort effects both in men and in women, with higher estimates moving from survey to survey to older age-groups. Removing the effect of the different age structures smoking prevalence in men is decreasing between periods, from 35.2% [95% Confidence Interval (95%CI): 34.2; 36.2] for 1987 to 28.8% (95%CI: 27.8; 29.9) in 2005/2006. Unemployed (from 40.6 in 2005 to 51.6 in 1995), divorced (range: 44.9% in 2005 to 58.4% in 1987), resident in Alentejo (range: 34.1% in 2005 to 46.8% in 1987), non-qualified workers (range: 35.8% in 1995 to 42.7% in 1987) had the highest smoking prevalences. No trends were observed by occupation, marital status, region and professional category. Similar analysis in women showed that smoking prevalence is increasing: 6.0% (95%CI: 5.6; 6.4) in 1987 to 11% (95%CI: 10.6; 11.9) in 2005/2006. Across the different surveys we observed that divorced (range: 19.3% in 1987 to 27.4% in 1995) and resident in Lisbon (range: 9.2 % in 1987 to 16.0% in 2005) women had the highest smoking prevalences. No trends were observed in marital status and region. In the educational level we observed a trend, where a higher prevalence was verified for the high education in 1987 (23.4%) and 1995 (18.2) switching for high school in more recent surveys (18.9% and 14.8% for 1998 and 2005, respectively). No patterns were identified for the remaining variables in either gender. Conclusions: Smoking trends have some differences in Portuguese men and women irrespective of age effects, with prevalence diminishing among men and rising among women. Smokers profiles also differ by gender, with highest tobacco consumption in men observed in more deprived socio-economical groups, while in women the pattern seems to affect more affluent groups.
- Nowcasting influenza epidemics using a sentinel network based influenza surveillance systemPublication . Nunes, Baltazar; Natário, Isabel; Carvalho, Maria LucíliaBackground: Timeliness of a public health surveillance system (SS) is one of its most important characteristics. In Europe the epidemiological surveillance of influenza is supported by general practitioners (GP) sentinel networks and, weekly, epidemiological bulletins are issued between Wednesday and Friday, reporting the previous week observed influenza values, representing a 2 to 4 days reporting delay. Some SS use web interfaces or computer routines that can provide up to date daily data streams accessing the current situation. The process of predicting the present week situation using the available incomplete information from the SS has received the term nowcasting and has high public health interest. Objective: Develop a statistical model to nowcast the influenza epidemic evolution in a weekly basis, by predicting two measures of interest: the current week influenza-like illness (ILI) rate (officially issued in the following week) and the probability that the influenza activity is epidemic. Methods: A two states (epidemic/non-epidemic) non-homogeneous hidden Markov model (HMM) is used, where the current week ILI rate is a function of an early observation of the ILI rate obtained by Friday of this week. The state-transition probabilities are modeled by a logistic function of the Friday ILI rate and of the number of ILI cases tested positive in the previous week. For comparison purposes a homogeneous HMM is also applied to the data. Bayesian inference is used to find estimates of the model parameters and of the nowcasted quantities. The models are applied to data provided by the Portuguese influenza SS for seasons 2008-09 up to 2010-11 to nowcast in real-time each week of the season 2010-11. Results: The non-homogenous HMM presents the best fit and is able to indentify four epidemic waves in the studied period, one in 2008-09 and 2010-11 and two in the pandemic season. Regarding the nowcast, the weekly ILI rates of season 2010-11 are predicted during the same week in a very satisfactory way, given that the estimates start to increase, reach the peak and decrease in synchrony with the observed rate (this reduces the reporting delay in 5 days). The non-homogenous model is able to detect the epidemic start two weeks before the homogeneous one. Conclusion: The present work shows the additional value of the non-homogeneous HMM to nowcast the ILI rate and the influenza activity state.
- Performance Comparison of the enzymatic parameters obtained by the participants of the PNCQ and the PNAEQ – “Study Collaboration” between Brazil and PortugalPublication . Valpassos, André; Menezes, Maria Elizabeth; Corrêa, José Abol; Correia, Helena; Silva, Rita; Brito, Cristina; Faria, Ana PaulaThe National External Quality Assessment Program (PNAEQ), inserted in the National Health Institute Dr. Ricardo Jorge (INSA, IP) and the National Program of Quality Control (PNCQ), supported by the Brazilian Society of Clinical Analysis, organizes and coordinates programs for the External Quality Assessment Laboratory. A comparative study was performed between Portugal and Brazil in order to detect similarities, and/or differences, of the results provided by the laboratories that participate in the program “External Quality Control” in both countries. Given the wide range and the variability in the determination of enzymes, a comparative test was performed between the two countries.
- Importância da fase pré-analítica nos exames moleculares - Interação entre Laboratórios de Apoio e Laboratórios ApoiadosPublication . Faria, Ana Paula1. Laboratório de apoio e laboratório apoiado:Interacção/Responsabilidades 2. Formas de Apoio: Normas, Guidelines e Boas Práticas 3. Fase Pré-Analítica e interacção das fases em Biologia molecular 4. Métricas de monitorização: Auditorias, AEQ, Indicadores, Inquéritos