Percorrer por autor "Barbosa, Rui"
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- Cianobactérias e cianotoxinas no contexto One Health: desafios regulatórios e de gestãoPublication . Barbosa, Rui; Freitas, Marisa; Ruivo, Manuela; Campos, AlexandreAs florescências de cianobactérias e as respetivas cianotoxinas representam um risco à saúde humana, animal e dos ecossistemas, enquadrando-se no “One Health”. Potenciadas pela eutrofização e pelas alterações climáticas, estas ocorrências comprometem a qualidade de água e perturbam processos ecológicos e biogeoquímicos. As principais cianotoxinas, icluem microcistinas, cilindrospermopsinas, anatoxina-a e saxitoxina, com efeitos hepáticos, imunotóxicos e neurológicos. Este estudo analisa os impactos das cianobactérias e cianotoxinas nas três dimensões One Health, identificando os principais desafios regulamentares. Realizou-se uma revisão bibliográfica sobre a integração deste tema no enquadramento One Health e uma análise crítica da legislação e orientações nacionais e internacionais. A pesquisa incluiu publicações científicas nas bases de dados Scopus, Web of Science e PubMed, abrangendo artigos publicados entre 2010 e 2024. Resultados: A exposição humana pode ocorrer através do consumo de água contaminada, contacto dérmico ou ingestão de alimentos provenientes dos ecossistemas afetados. Nos animais, a exposição ocorre sobretudo pela ingestão de água e alimentos contaminados, manifestando-se na mortalidade de gado, animais domésticos e selvagens. A nível ambiental, ocorrem variações na biomassa de fitoplâncton, promovendo a formação de zonas hipóxicas, comprometendo funções ecológicas dos ecossistemas. Estes fenómenos acarretam perdas económicas, incluindo custos acrescidos no tratamento de água, perdas na produção agropecuária e piscícola, no turismo e na recuperação dos ecossistemas. A nível Europeu, o limite para microcistina-LR na água de consumo é 1 µg/L, com gestão de risco ao longo do sistema de abastecimento, sem valores definidos para outras cianotoxinas. Em Portugal, este limite é adotado, sendo a monitorização intensificada quando densidade de cianobactérias potencialmente produtoras de toxinas excede 2.000 células/mL. Para águas recreativas, prevê-se que a presença de florescências seja sinal de alerta, cabendo aos serviços de saúde pública avaliar o risco e implementar medidas de gestão adequadas, mesmo na ausência de valores quantitativos regulamentares. No que concerne às águas de irrigação, tanto a nível nacional como Europeu, a legislação não define parâmetros específicos, evidenciando lacunas. Estas constatações evidenciam a necessidade de uma gestão integrada e multidisciplinar, combinando monitorização, avaliação e comunicação intersectorial, para mitigar os efeitos das cianobactérias e cianotoxinas, garantindo a proteção dos princípios One Health.
- Honey from natural park of Montesinho: insights from DNA extraction methodology for botanical identificationPublication . Soares, Sónia; Magalhães, Leandro; Barbosa, Rui; Delerue-Matos, CristinaHoney is a sweet natural substance produced by bees from the nectar of plants and/or secretions of living parts of plants. It consists essentially of simple sugars (68%) and water (18%) and smaller quantities of other components such as vitamins, minerals, proteins, organic acids, phenolic compounds, among others. Those are highly dependent of the botanical species visited by bees, conferring to each honey different and distinct organoleptic and biological properties. The botanical differences give rise to two types of honeys, monofloral, consisting essentially of the nectar of a single plant species, and multifloral, arising from several plant species. This strict relation of botanical origin and its biological and organoleptic properties lead to a quality distinction of honey types. There are honeys with high market values due to its particular flavour, taste and specific biological properties, such as monofloral honey and honeys with the denomination of Protected Designation of Origin, such as honey produced in Natural Park of Montesinho. With this, honey is produced and marketed based on its colour, flavour, density and biological properties, being extremely important to assess its quality and authenticity. DNA-based methods are simple, fast and precise promising tools for species identification. However, honey is a complex matrix with high amounts of sugars and other compounds that inhibit the PCR reaction. Thus, it is important to find the best DNA extraction method to achieve good yields and purities. In this work, different pre-treatments were performed and results were compared. For the DNA extraction, a commercial DNA extraction kit was used. The quality of DNA extracts was assessed by spectrophotometry and electrophoresis. Results revealed that the use of ultrasounds in honey pre-treatments achieved the best yields and purity. Additionally, a PCR amplification targeting the gene 18S rRNA was performed to evaluate amplifiability of the extracted DNA. As expected, all extract samples revealed to have amplifiable DNA. Combining a simple and easy honey pre-treatment with an effective DNA extraction method, allows us to get desired good extracts. Thus, this methodology is the first step for further studies involving botanical identification of honey and honey quality studies.
- Importance of climate change manifestations and urban green areas on the potential expansion of ixodid vectorsPublication . Barbosa, Rui; Monteiro, Ana; Freitas, MarisaUrban development combined with climate change can trigger negative effects in the ecosystems. Although the recognized environmental benefits, the implementation of urban green areas can increase the number of habitats favorable to the spread of ixodid vectors, as well as to increase its contact with humans and animals, which may constitute a public health problem. Nowadays, to increase the effectiveness of health services intervention, is necessary to create multidisciplinary teams. In this context, geography, through Geographic Information Systems (GIS), plays a crucial role. This software contributes to operate and export geographic alphanumeric information in a global, regional, or local scale. The aim of this study was to conjecture the potential vulnerabilities of climate change and the expansion of urban green areas on the occurrence of ixodid vectors in urban environments. Besides, it is intended to demonstrate the application of GIS methodology in delimiting higher risk zones and to propose new locations for ixodid vectors surveillance. The study area was composed by four municipalities of Porto metropolitan zone (Northern Portugal). The study was divided into three topics: characterization of local climate conditions, climate forecasts as well as green areas, surveillance data of ixodid vectors in the study area, identification of susceptible and risk areas of ixodid vectors expansion. The expansion of vectors in urban area was confirmed, evidencing that climate change combined with urban green areas can result in an increased dissemination of ixodid vectors in urban environments, consequently, may increase the incidence of diseases transmitted by them. This study shows that GIS constitute a profitable tool for a more fruitful site demarcation of ixodid vectors monitoring, increasing the success of its capture in the free-living phase. The more active identification of risk areas will allow health services to take more effective measures.