Browsing by Author "Viegas, Carla"
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- Accessing indoor fungal contamination using conventional and molecular methods in Portuguese poultriesPublication . Viegas, Carla; Malta-Vacas, Joana; Sabino, Raquel; Viegas, Susana; Veríssimo, CristinaEpidemiological studies showed increased prevalence of respiratory symptoms and adverse changes in pulmonary function parameters in poultry workers, corroborating the increased exposure to risk factors, such as fungal load and their metabolites. This study aimed to determine the occupational exposure threat due to fungal contamination caused by the toxigenic isolates belonging to the complex of the species of Aspergillus flavus and also isolates fromAspergillus fumigatus species complex. The study was carried out in seven Portuguese poultries, using cultural and molecularmethodologies. For conventional/cultural methods, air, surfaces, and litter samples were collected by impaction method using the Millipore Air Sampler. For the molecular analysis, air samples were collected by impinger method using the Coriolis μ air sampler. After DNA extraction, samples were analyzed by real-time PCR using specific primers and probes for toxigenic strains of the Aspergillus flavus complex and for detection of isolates from Aspergillus fumigatus complex. Through conventional methods, and among the Aspergillus genus, different prevalences were detected regarding the presence of Aspergillus flavus and Aspergillus fumigatus species complexes, namely: 74.5 versus 1.0% in the air samples, 24.0 versus 16.0% in the surfaces, 0 versus 32.6% in new litter, and 9.9 versus 15.9%in used litter. Through molecular biology, we were able to detect the presence of aflatoxigenic strains in pavilions in which Aspergillus flavus did not grow in culture. Aspergillus fumigatus was only found in one indoor air sample by conventional methods. Using molecular methodologies, however, Aspergillus fumigatus complex was detected in seven indoor samples from three different poultry units. The characterization of fungal contamination caused by Aspergillus flavus and Aspergillus fumigatus raises the concern of occupational threat not only due to the detected fungal load but also because of the toxigenic potential of these species.
- Accessing occupational exposure to fungi in a cork industryPublication . Viegas, Carla; Clérigo, Anália; Faria, Tiago; Sabino, Raquel; Gomes, Anita Quintal; Viegas, SusanaDifferent forms of fungal diseases affecting the nose and paranasal sinuses are recognized, including invasive and non-invasive fungal rhinosinusitis. Penicillium glabrum complex is associated with respiratory diseases such as suberosis, a typical disease of cork industry workers. In addition, Chrysonilia sitophila has been described as causing occupational asthma, associated to prolonged exposure to high counts of spores. In this study we aimed to access fungal exposure in workers from one cork industry through the mycological analysis of their nasal exudate and the environmental fungal contamination of their surroundings as well.
- Adaptação de um instrumento de avaliação qualitativa do risco químico em anatomia patológicaPublication . Ferro, Amadeu Borges; Ladeira, Carina; Viegas, Carla; Ribeiro, Cátia; Figueira, Edite; Albuquerque, Paula; Quintino, FernandaOs agentes químicos são frequentemente manipulados nos laboratórios de anatomia patológica. Existem diversos estudos que comprovam a existência de uma associação entre a exposição a produtos químicos e o desenvolvimento de determinadas patologias, demonstrando, assim, a importância da avaliação e monitorização deste tipo de agentes. Pretendeu-se, com este trabalho, caracterizar a exposição dos técnicos de anatomia patológica aos agentes químicos através de um instrumento baseado no International Chemical Control Toolkit, no serviço de histopatologia dos laboratórios de anatomia patológica da região de Lisboa e Vale do Tejo.
- Aflatoxin B1 can also be an occupational risk factor! How biomonitoring helped to evidence thisPublication . Viegas, Susana; Almeida, Ana; Veiga, Luísa; Viegas, CarlaExposure to mycotoxins is not usually identified as a risk factor present in occupational settings. This is probably due to the inexistence of limits regarding the concentration of airborne mycotoxins, and also due to the fact that these compounds are rarely monitored in occupational environments. Aflatoxin B1 (AFB1) is the most prevalent aflatoxin and is associated with carcinogenicity, teratogenicity, genotoxicity, and immunotoxicity. Although dietary exposure to AFB1 has been extensively documented, only a small number of studies examined exposure in occupational settings. The aim of study - A study was developed aiming to know exposure to AFB1 in four occupational settings: poultry and swine production, poultry slaughterhouse, and waste management.
- Air contaminants in animal production: the poultry casePublication . Viegas, Carla; Viegas, Susana; Monteiro, Ana; Carolino, Elisabete; Sabino, Raquel; Veríssimo, C.A descriptive study was developed in order to assess air contamination caused by fungi and particles in seven poultry units. Twenty seven air samples of 25 litters were collected through impaction method. Air sampling and particle concentration measurement were performed in the pavilions’ interior and also outside premises, since this was the place regarded as reference. Simultaneously, temperature and relative humidity were also registered. Regarding fungal load in the air from the seven poultry farms, the highest value obtained was 24040 CFU/m3 and the lowest was 320 CFU/m3. Twenty eight species/genera of fungi were identified, being Scopulariopsis brevicaulis (39.0%) the most commonly isolated species and Rhizopus sp. (30.0%) the most commonly isolated genus. From the Aspergillus genus, Aspergillus flavus (74.5%) was the most frequently detected species. There was a significant correlation (r=0.487; p=0.014) between temperature and the level of fungal contamination (CFU/m3). Considering contamination caused by particles, in this study, particles with larger dimensions (PM5.0 and PM10) have higher concentrations. There was also a significant correlation between relative humidity and concentration of smaller particles namely, PM0.5 (r=0.438; p=0.025) and PM1.0 (r=0.537; p=0.005). Characterizing typical exposure levels to these contaminants in this specific occupational setting is required to allow a more detailed risk assessment analysis and to set exposure limits to protect workers’ health.
- Air fungal contamination in ten hospitals’ food units from LisbonPublication . Viegas, Carla; Ramos, C.; Almeida-Silva, Marina; Sabino, Raquel; Veríssimo, Carlos; Rosado, LauraA descriptive study was developed to monitor air fungal contamination in ten food units from hospitals. Fifty air samples of 250 litres were collected through impaction method. Samples were collected in food storage facilities, kitchen, food plating, canteen and also, outside premises, since this is the place regarded as reference. Simultaneously, environmental parameters were also monitored, including temperature and relative humidity through the equipment Babouc, LSI Sistems and according to the International Standard ISO 7726.
- Air fungal contamination in two elementary schools in Lisbon, PortugalPublication . Viegas, Carla; Veríssimo, C.; Rosado, Laura; Santos, Carlos SilvaA descriptive study was developed to monitor air fungal contamination in two elementary schools in Lisbon, Portugal. Eight air samples of 250 litres through impaction method were collected in canteen, library, classrooms and also, outside premises as reference place. Simultaneously, were also monitored environmental parameters, including temperature, and humidity through the equipment Babouc, LSI Sistems and according to the International Standard ISO 7726 - 1998. Considering both schools, sixteen different species of fungi in air were identified, being the 2 most commonly isolated Cladosporium sp. (51,1%) and Penicillium sp. (27,5%). Besides these genera Trichoderma, Aspergillus, Alternaria, Chrysonilia, Botritys, Ulocladium, Athrium, Aureobasidium, Phoma, Scedosporium e Geotrichum were also isolated. Regarding yeasts, Candida sp., Cryptococcus sp. and Rhodotorula sp. were isolated. The youngest school, as well canteens in each school, presented the worst results concerning the air fungal contamination, maybe due to the higher number of occupants. There was no significant relationship (p>0,05) between fungal contamination and temperature and humidity.
- Airborne food allergen and aeroallergen levels in healthcare settings: an unaccounted but potentially relevant source of exposure?Publication . Leal, M.; Paciência, I.; Farraia, M.; Cavaleiro Rufo, J.; Castro Mendes, F.; Delgado, L.; Viegas, Carla; Moreira, A.Background: Exposure to airborne allergens of biological origin associates with the development and exacerbation of allergic asthma and rhinitis. Assessment of allergens' exposure in healthcare facilities may contribute to monitor hygiene and survey specific allergens which may cause symptoms in sensitized subjects. Objective: To assess the concentration of indoor and airborne food allergens across different healthcare settings. Methods: Dust was vacuumed from primary health care centers in Lisbon; and emergency unit, day hospital, internal medicine ward, operating room, and the outpatient clinic of a university central hospital in Porto. Samples were sieved, weighed, extracted and concentrations of Nbos d 5, Cor a 9, Gal d 2, Ara h 3, Ara h 6, Der p 1, Fel d 1, Can f 1, Bla g 2, Alt a 1, and Phl p 5 were determined using a multiplex array for allergens (MARIA™). Results: All airborne food and aeroallergens were found at least in one sampled area, except for Alt a 1. Levels of Der p 1 and Fel d 1 ranged from 13.0 µg/g to 971.0 µg/g and from 7.0 µg/g to 4618.8 µg/g, respectively. The emergency unit revealed the higher levels of food allergens, namely Nbos d 5 (16034.0 µg/g) and Cor a 9 (10649.5 µg/g). Conclusions: With the exception of the operating room, exposure levels of dust mite, cat and dog allergens in healthcare facilities were above the values associated with sensitization and occurrence of allergic asthma or rhinitis symptoms in sensitized subjects.
- Algorithm to assess the presence of Aspergillus fumigatus resistant strains: the case of Norwegian sawmillsPublication . Viegas, Carla; Almeida, Beatriz; Aranha Caetano, Liliana; Afanou, Anani; Straumfors, Anne; Veríssimo, Cristina; Gonçalves, Paulo; Sabino, RaquelAssociation between selection pressure caused by the use of azole fungicides in sawmills and the development of fungal resistance has been described. The aim of this study was to implement an algorithm to assess the presence of Aspergillus section Fumigati resistant strains in sawmills. Eighty-six full-shift inhalable dust samples were collected from eleven industrial sawmills in Norway. Different culture media were used and molecular identification to species level in Aspergillus section Fumigati was done by calmodulin sequencing and TR34/L98H and TR46/Y121F/T289A mutations were screened by real-time PCR assay and confirmed by cyp51A sequencing. Six Fumigati isolates were identified as A. fumigatus sensu stricto and two of these grew on azole-supplemented media and were further analyzed by real-time PCR. One was confirmed to be a TR34/L98H mutant. The obtained results reinforce the need to assess the presence of A. fumigatus sensu stricto resistant isolates at other workplaces with fungicide pressure.
- Alterações climáticas e impacto na qualidade da águaPublication . Viegas, CarlaA frase de Johan Rockstrom parece cada vez mais aplicável em Portugal. Para além das situações de seca (um problema de disponibilidade de água que decorre de um défice anormal de precipitação), Portugal é candidato a país de elevado risco para escassez ou ‘stress hídrico’ a médio prazo [segundo projecções do World Resources Institute para 2040], ou seja, de poder vir a ter uma procura que exceda a oferta de água acessível e com a qualidade necessária para a sua utilização. Apesar da situação no país não ser homogénea (a região abaixo do Tejo é a mais vulnerável), nos últimos anos as secas em Portugal tornaram-se mais frequentes, mais prolongadas e mais abrangentes. Devido ao aumento da frequência de fenómenos climáticos extremos, as alterações climáticas têm interferência não só na quantidade, como na qualidade dos recursos hídricos. Embora a água permaneça no seu ciclo, não está disponível na quantidade e qualidade necessárias.