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- Possible aflatoxin presence in Portuguese poultry unitsPublication . Viegas, Susana; Viegas, Carla; Raquel, Sabino; Veríssimo, CristinaIntroduction: Aflatoxins are known to be human carcinogens based on sufficient evidence of carcinogenicity in humans (hepatocellular carcinoma, or primary liver-cell cancer). Aflatoxin B1 is one of the most deeply studied mycotoxins, known for a long time as belonging to the group of toxins produced by the genus Aspergillus (A. flavus, A. parasiticus, A. nominus). The presence in food stuffs depends on their geographical origin and production methods. Occupational exposure to aflatoxins can occur by inhalation of dust generated during the handling and processing of contaminated crops and feeds. Therefore, farmers and other agricultural workers have one of the greatest risks of occupational exposure to these mycotoxins. Objective: To characterize A. flavus prevalence in seven poultry units, with emphasis to the possible presence of aflatoxin in the air. Methods: A descriptive study was developed to monitor air fungal contamination in seven poultry units. Nineteen interior air samples of 25 litres were collected through impaction method. Results: From the seven poultry units analyzed, A. flavus was found in three of them. From all fungal genus identified in the referred units, A. flavus was the third species most frequently found in air samples (7.23%). Moreover, in those units, and from the Aspergillus genus, A. flavus was the most frequently isolated species in air samples (74.5%). Conclusions: Regarding the observed results and considering the high number of units contaminated by fungi known as possible aflatoxin producers, we have to believe that exposition can occur by inhalation (workers) and ingestion (consumers). This situation might represent a public health problem considering that aflatoxin is a known cancer agent.
- Transcriptional regulation by antagonistic promoter binding of BCL-6 or Stat5 is modulated by Rac1 SignalingPublication . Barros, Patrícia; Jordan, Peter; Matos, Paulo
- Clinical, biochemical and molecular characterization of cystinuria in a cohort of 12 patients.Publication . Barbosa, M.; Lopes, A.; Mota, C.; Martins, E.; Oliveira, J.; Alves, S.; De Bonis, P.; Mota, M. do C.; Dias, Carlos Matias; Rodrigues-Santos, P.; Fortuna, A.M.; Quelhas, D.; Lacerda, L.; Bisceglia, L.; Cardoso, M.L.Cystinuria is a rare autosomal inherited disorder characterized by impaired transport of cystine and dibasic aminoacids in the proximal renal tubule. Classically, Cystinuria is classified as type I (silent heterozygotes) and non-type I (heterozygotes with urinary hyperexcretion of cystine). Molecularly, Cystinuria is classified as type A (mutations on SLC3A1 gene) and type B (mutations on SLC7A9 gene). The goal of this study is to provide a comprehensive clinical, biochemical and molecular characterization of a cohort of 12 Portuguese patients affected with Cystinuria in order to provide insight into genotype–phenotype correlations. We describe seven type I and five non-type I patients. Regarding the molecular classification, seven patients were type A and five were type B. In SLC3A1 gene, two large genomic rearrangements and 13 sequence variants, including four new variants c.611-2A>C; c.1136+44G>A; c.1597T (p.Y533N); c.*70A>G, were found. One large genomic rearrangement was found in SLC7A9 gene as well as 24 sequence variants including 3 novel variants: c.216C>T (p.C72C), c.1119G>A (p.S373S) and c.*82C>T. In our cohort the most frequent pathogenic mutations were: large rearrangements (33.3% of mutant alleles) and a missense mutation c.1400T>C ( p.M467T) (11.1%). This report expands the spectrum of SLC3A1 and SLC7A9 mutations and provides guidance in the clinical implementation of molecular assays in routine genetic counseling of Portuguese patients affected with Cystinuria.
- Optimization of Enzymatic Extraction for HPLC Quantification of Vitamin B2Publication . Flores, Cristina; Santos, MarianaThe purpose of this study was to optimize the enzymatic extraction for HPLC quantification of vitamin B2 in foodstuffs, by testing Takadistase to replace one of the enzymes (α-amylase) employed in the implemented method and, to change the extraction incubation temperature, in order to optimize equipment utilization. For the optimization of the enzymatic extraction we first tested the replacement of the previous enzymatic mixture; α-amylase (0,5g/sample) + β-amylase (0.05g/sample) for: A -Takadistase (2g / sample) and β-amylase (0.05g / sample) and B- Takadistase (1g / sample) and β-amylase (0.05g / sample). After proving the new mixture efficiency, we tested the reduction of Takadiastase quantity to 0.5 g and 0.25 g. Afterwards, we tested the incubation temperature change from 40º to 37ºC. Chromatographic separation was performed, at 37 ºC, by reverse phase high performance liquid chromatography with fluorometric detection (excitation and emission wavelengths 422 nm and 522 nm, respectively). A chromatographic column Phenomenex Luna 5 μm C18 1000A column (250 x 4.6 mm) was empolyed. The mobile phase consisted of 0.05 mol/l acetate buffer + Methanol (70+30) with a flow rate of 1 ml/min. Quantification was made by external calibration. To compare the enzyme replacement, breakfast cereals (FAPAS) were used as test samples. We used milk powder, spiked with riboflafin-5P, to test enzyme quantities and infant formula to test different incubation temperatures. Accuracy was verified by running proficiency test samples (FAPAS). ANOVA tests proved that there are no significant differences between vitamin B2 content obtained with the different enzyme treatments (Takadistase + β-amylase; α-amylase + β-amylase) or with the different incubation temperatures. The results obtained with the different enzyme quantities, also proved to be equivalent after tested trough ANOVA. In all cases we considered p=0.05. Enzymatic extraction performed with Takadistase (0.25 g/sample) and β-amylase (0.05 g/sample) at 37ºC, proved to be efficient and contributed to optimize the existing laboratory equipment utilization and test cost.
- Ocurrence and bioacessibility of nitrates in baby foodsPublication . Pina, Zeila; Alvito, Paula; Vasco, Elsa
- Arsenic speciation in rice and fish using HPLC-ICP-MSPublication . Coelho, Inês; Gueifão, Sandra; Castanheira, IsabelChemical speciation in foodstuffs is of uttermost importance since it is nowadays recognized that both toxicity and bioavailability of an element depend on the chemical form in which the element is present. Regarding arsenic, inorganic species are classified as carcinogenic while organic arsenic, such as arsenobetaine (AsB) or arsenocholine (AsC), is considered less toxic or even non-toxic. Coupling a High Performance Liquid Chromatographer (HPLC) with an Inductively Coupled Plasma Mass Spectrometer (ICP-MS) combines the power of separation of the first with the selectivity and sensitivity of the second. The present work aims at developing a method, using HPLC-ICP-MS technique, to identify and quantify the chemical species of arsenic present in two food matrices, rice and fish. Two extraction methods, ultrasound and microwave, and several conditions were studied. The best method was chosen based on recovery percentages. To ensure that no interconversion of species was occurring, individual spikes of each species of arsenic were made in both matrices and recovery rates were calculated. To guaranty accurate results reference material BCR-627 TUNA FISH, containing certified values for AsB and DMA, was analyzed. Chromatographic separation was achieved using an anion exchange column, HAMILTON-PRP X-100, which allowed to separate the four arsenic species for which standards were available (AsB, dimethylarsenic (DMA), arsenite (AsIII), arsenate (AsV). The mobile phase was chosen based on scientific literature and adjusted to laboratory conditions. Different gradients were studied. As a result we verified that the arsenic species present in both matrices were not the same. While in fish 90% of the arsenic present was in the form of arsenobetaine, in rice 80% of arsenic was present as DMA and 20% as inorganic arsenic. Our results demonstrate that HPLC coupled to ICP-MS is a crucial tool to identify arsenic chemical species that can be present in foodstuffs.
- Inquérito de Saúde com Exame FísicoPublication . Departamento de Epidemiologia; Departamento de Promoção da Saúde e Doenças CrónicasO Inquérito de Saúde com Exame Físico (INSEF - Componente nacional do Inquérito Europeu de Saúde com Exame físico -EHES) tem como objetivo construir conhecimento científico sobre a saúde da População residente em Portugal, disponibilizando informação que apoie as atividades de planeamento e avaliação em saúde e, assim, potenciar a adequação das políticas nacionais às necessidades de bem-estar da população. Constitui também um objetivo deste trabalho proceder a um diagnóstico de saúde da população de São Brás de Alportel, que possibilite caracterizar o estado de saúde da população residente, os seus fatores determinantes e a utilização de cuidados de saúde e caracterizar esta população a nível antropométrico, hematológico, bioquímico e genético.
- Prevalence and risk factors for Giardia duodenalis infection among children: A case study in PortugalPublication . Júlio, Cláudia; Vilares, Anabela; Oleastro, Mónica; Ferreira, Idalina; Gomes, Salomé; Monteiro, Lurdes; Nunes, Baltazar; Tenreiro, Rogério; Ângelo, HelenaBackground: Giardia duodenalis is a widespread parasite of mammalian species, including humans. The prevalence of this parasite in children residing in Portugal is currently unknown. This study intended to estimate G. duodenalis infection prevalence and identify possible associated risk factors in a healthy paediatric population living in the District of the Portuguese capital, Lisbon. Methods: Between February 2002 and October 2008, 844 children were randomly selected at healthcare centres while attending the national vaccination program. A stool sample and a questionnaire with socio-demographic data were collected from each child. Giardia infection was diagnosed by direct examination of stools and antigen detection by ELISA. Results: The population studied revealed a gender distribution of 52.8% male and 47.2% female. Age distribution was 47.4% between 0-5 years and 52.6% between 6-15 years. The prevalence of Giardia infection was 1.9% (16/844) when estimated by direct examination and increased to 6.8% (57/844) when ELISA results were added. The prevalence was higher among children aged 0-5 years (7.8%), than among older children (5.8%), and was similar among genders (6.9% in boys and 6.5% in girls). The following population-variables were shown to be associated risk factors for G. duodenalis infection: mother’s educational level (odds ratio (OR)= 4.49; confidence interval (CI): 1.20-16.84), father’s educational level (OR = 12.26; CI: 4.08-36.82), presence of Helicobacter pylori infection (OR = 1.82; CI: 1.05-3.15), living in houses with own drainage system (OR = 0.10; CI: 0.02-0.64) and reported household pet contact, especially with dogs (OR = 0.53; CI: 0.31-0.93). Conclusion: The prevalence of giardiasis in asymptomatic children residing in the region of Lisbon is high. Several risk factors were associated with Giardia prevalence and highlight the importance of parents’ education and sanitation conditions in the children’s well being. The association between G. duodenalis and H. pylori seems an important issue deserving further investigation in order to promote prevention or treatment strategies
- Relatório de Actividades da EP Solo e Sedimentos 2009-2011Publication . Moura, Isabel; Rodrigues, Fernanda; Moreira, Sandra; Santiago, Anabela; Reis, Luís; Frazão, Manuel; Pestanudo, Susana; Brandão, João; Aires, Cristina; Domingues, Hermínia; Branco, Maria Amélia; Serrão, Maria da Graça; Dias, Elisabete; Batista, Maria JoãoO Plano Nacional de Acção Ambiente e Saúde (PNAAS), aprovado pela Resolução do Conselho de Ministros n.º 91/2008, de 4 de Junho, visa melhorar a eficácia das políticas de prevenção, controlo e redução de riscos para a saúde com origem em factores ambientais, promovendo a integração do conhecimento e a inovação, e contribuir para o desenvolvimento económico e social do país. A implementação deste Plano reveste-se de particular importância, face à necessidade de uma abordagem nacional, integrada e global de «Ambiente e Saúde». O PNAAS é constituído por 36 Acções Programáticas relativas aos seguintes Domínios Prioritários: água, ar, solo e sedimentos, químicos, alimentos, ruído, espaços construídos, radiações e fenómenos meteorológicos. As Acções Programáticas encontram-se consubstanciadas em Fichas de Projecto, elaboradas por Equipas de Projecto (EPs) emanadas do Grupo de Trabalho Ambiente e Saúde (GTAS). Uma destas EPs é a EP Solo e Sedimentos, que tem como missão implementar duas Acções do Plano, as quais são seguidamente apresentadas: Acção I.6 “Levantamento de informação e/ou monitorização de poluentes no solo e materiais sedimentares”, que tem como objectivos: o Identificar, avaliar e monitorizar os locais do território nacional cujos solos e materiais sedimentares estão contaminados, ou são susceptíveis de o serem; o Identificar os respectivos contaminantes. Acção I.7 “Levantamento de efeitos na saúde humana associados a poluentes presentes em solos e materiais sedimentares e definição de estratégia de intervenção”, que tem como objectivos: o Sistematizar os efeitos na saúde humana associados a solos e materiais sedimentares contaminados; o Definir e implementar uma estratégia de intervenção. Integram a EP Solo e Sedimentos as seguintes Entidades: Agência Portuguesa do Ambiente (APA), Direcção-Geral da Saúde (DGS), Direcção-Geral de Agricultura e Desenvolvimento Rural (DGADR), Empresa de Desenvolvimento Mineiro, S.A. (EDM), Instituto Nacional de Saúde Dr. Ricardo Jorge (INSA), Instituto Nacional de Recursos Biológicos, I.P. (INRB), Instituto Portuário e de Transportes Marítimos, I.P. (IPTM) e Laboratório Nacional de Energia e Geologia, I.P. (LNEG). Embora as Entidades supra-referidas tenham sido formalmente nomeadas, nem todas têm participado nas actividades da EP Solo e Sedimentos. Identificam-se, em seguida, os elementos representativos desta EP que têm colaborado activamente nos trabalhos desenvolvidos e que participaram na elaboração do presente Relatório: Isabel Moura, Fernanda Rodrigues e Sandra Moreira da APA, Anabela Santiago da DGS, Luís Reis, Manuel Franco Frazão e Susana Pestanudo da DGADR, João Brandão do INSA, Cristina Sempiterno Aires, Hermínia Domingues, Maria Amélia Castelo Branco e Maria da Graça Serrão do INRB, Elisabete Dias do IPTM e Maria João Batista do LNEG. A EDM prestou uma colaboração pontual no esclarecimento de aspectos específicos, no âmbito das suas competências e atribuições. Não foi atribuída verba específica para a implementação do PNAAS na sequência da sua aprovação, pelo que este constrangimento condicionou a concretização das Acções Programáticas estabelecidas, bem como a normal execução do Plano. Dada a conjuntura económica nacional, mas tendo presente a importância da implementação do PNAAS no que respeita ao fortalecimento do conhecimento nacional em matéria de Ambiente e Saúde e no cumprimento dos compromissos internacionais assumidos, designadamente os resultantes da 5ª Conferência Ministerial de Ambiente e Saúde (realizada em Parma, no ano de 2010, sob os auspícios da Organização Mundial da Saúde), as Entidades Coordenadoras do PNAAS, APA e DGS, solicitaram às EPs, no decurso da reunião geral de 3 de Fevereiro de 2009, que identificassem as Acções, ou Fases, passíveis de serem desenvolvidas com os recursos disponíveis, sem qualquer financiamento complementar. A EP Solo e Sedimentos aferiu ser possível concretizar o início da Fase 1 da Acção Programática I.6. “Levantamento dos locais contaminados e/ou susceptíveis de poluição antropogénica e geogénica, com base em dados históricos disponíveis nas várias Instituições”. A EP Solo e Sedimentos acordou elaborar um documento técnico que compilasse o trabalho desenvolvido para a concretização da Fase 1 da referida Acção Programática. Em Maio de 2011, foi participado à EP que a APA estava a preparar um documento sobre solos contaminados que iria ser submetido à tutela para aprovação, o qual pretende vir a ser adoptado como uma estratégia nacional para os solos contaminados. Perante este facto e não tendo a EP Solo e Sedimentos conhecimento do conteúdo do referido documento, optou-se por substituir o documento técnico da EP por um Relatório de Actividades que sistematizasse o trabalho desenvolvido entre Fevereiro de 2009 e o presente. Dada a complexidade que as questões de Solo e Sedimentos versus Saúde Humana reúnem e a diversidade de abordagens possíveis para a implementação da referida Acção Programática, associada ao facto de a EP ser constituída por diferentes Entidades com atribuições e competências diversas na matéria, foi decidido: i) consubstanciar as actividades da EP em instrumentos político-legais internacionais e nacionais; ii) proceder à harmonização e concertação de terminologia e de conceitos entre os peritos da EP; iii) concretizar algumas reflexões temáticas, em sede das reuniões da EP. As consequentes determinações e considerações da EP encontram-se vertidas ao longo do Relatório, sendo ainda apresentadas algumas Recomendações que visam prestar um contributo para aqueles que trabalham nesta temática.
- Analysis and visualization of chromosome informationPublication . Tenreiro Machado, J.A.; C. Costa, António; Quelhas, Maria DulceThis paper analyzes the DNA code of several species in the perspective of information content. For that purpose several concepts and mathematical tools are selected towards establishing a quantitative method without a priori distorting the alphabet represented by the sequence of DNA bases. The synergies of associating Gray code, histogram characterization and multidimensional scaling visualization lead to a collection of plots with a categorical representation of species and chromosomes.