Browsing by Author "Pires, M.J."
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- An Antisense Oligonucletide based therapy for a rare disease: in vitro and in vivo studiesPublication . Gonçalves, M.; Matos, L.; Santos, J.I.; Coutinho, M.F.; Prata, M.J.; Pires, M.J.; Oliveira, P.A.; Alves, SandraMucolipidosis type II (ML II) is a Lysosomal Storage Disorder caused by the deficiency of the enzyme GlcNAc-1-phosphotransferase. This enzyme is responsible for the addition of the mannose-6-phosphate marker to lysosomal enzymes allowing their targeting to lysosomes. From the several ML II mutations, the deletion of two nucleotides from GNPTAB exon 19 (c.3503_3504del) is the most frequent, making it a good target for a mutation specific therapy. In this study, we explored an innovative therapeutic strategy based on the use of antisense oligonucleotides (ASOs) for ML II. In a previous study1 on fibroblasts from ML II patients, ASOs were used to skip exon 19 of the GNPTAB pre-mRNA, successfully resulting in the production of an in-frame mRNA. Currently, our objective is to evaluate the therapeutic potential of this approach, both in vitro in C57BL/6 fibroblasts and in vivo in C57BL/6 mice.
- Assessment of benzoquinones and mycotoxins in cereal flour samples from Portugal within SafeGrains projectPublication . Alvito, Paula; Hilário, C; Barros, G; Duarte, S; Pires, M.J.; Magro, A; Assunção, R.; Ferreira, RB; Carvalho, MOOne of the most relevant problems in stored grain is the contamination by insects and mycotoxin-producing fungi. The red flour beetle, Tribolium castaneum (Herbst) (Coleoptera, Tenebrionidae), one of the major key-pests of milled grain, is resistant to Beauveria bassiana infection, producing benzoquinone-containing defensive secretions, that reduce fungal germination and growth. It can be affirmed that the tenebrionid cuticular secretions have antifungal properties. For T. castaneum, p-benzoquinones such as methyl-1,4-benzoquinone (MBQ) and ethyl-1,4-benzoquinone (EBQ) are major components of defensive secretions used as repellents and irritants. SafeGrains project (PTDC/ASP‐PLA/28350/2017) intends to contribute to clarify the interaction among pest infestation and associated benzoquinones and fungus and produced mycotoxins. The present study aims to implement and validate two HPLC methodologies to determine benzoquinones and mycotoxins in cereal flour samples. In a first attempt, HPLC methods will be optimized and validated for cereal flour samples (linearity and working range, limits of detection (LOD) and quantification (LOQ) as well as recovery). Once attained the satisfactory analytical conditions for these determinations, the presence of both chemicals will be quantified in 5 flour samples from Portugal, contaminated with insects (T. castaneum) or fungi (mycotoxin producer as Aspergillus sp) or both. Results will be presented and discussed concerning its contents in benzoquinones and mycotoxins and possible interactive effects.
- Effects of Trihalomethanes on Liver MitochondriaPublication . Faustino-Rocha, A.I.; Rodrigues, D.; Gil da Costa, R.M.; Dinis, C.; Talhada, D.; Aragão, S.; Botelho, M.; Colaço, A; Pires, M.J.; Oliveira, M.M.; Peixoto, F; Oliveira, P.A.Introduction: Trihalomethanes (THMs), namely dibromochloromethane (DBCM) and bromodichloromethane (BDCM), are disinfection byproducts of chlorinated water. This experiment aimed to evaluate the mitochondrial dysfunction induced by THMs at low levels in a mouse model.
- Nutritional composition of ultra-processed plant-based foods in the out-of-home environment: a multi-country survey with plant-based burgersPublication . Vellinga, Reina E.; Rippin, H.L.; Gonzales, G.B.; Temme, E.H.M.; Farrand, C.; Halloran, A.; Clough, B.; Wickramasinghe, K.; Santos, M.; Fontes, T.; Pires, M.J.; Nascimento, A.C.; Santiago, S.; Burt, H.E.; Brown, M.K.; Jenner, H.K.; Alessandrini, R.; Marczak, A.M.; Flore, R.; Sun, Y.; Motta, C.Ultra-processed plant-based foods, such as plant-based burgers have gained in popularity. Particularly in the out-of-home (OOH) environment, evidence regarding their nutritional profile and environmental sustainability is still evolving. Plant-based burgers available at selected OOH sites were randomly sampled in cities of four WHO European Member States; Amsterdam, Copenhagen, Lisbon, and London. Plant-based burgers (patty, bread and condiment) (n=41) were lab-analysed for their energy, macronutrients, amino acids, and minerals content per 100g and serving, and were compared with reference values. For the plant-based burgers, the median values per 100g were: 234 kcal, 20.8g carbohydrates, 3.5g dietary fibre, and 12.0g fat, including 0.08g TFA and 2.2g SFA. Protein content was 8.9g/100g, with low protein quality according to amino acid composition. Median sodium content was 389mg/100g, equivalent to 1g salt. Compared with references, the median serving of plant-based burgers provided 31% of energy intake based on a 2,000 kcal per day, and contributed to carbohydrates(17-28%), dietary fibre(42%), protein(40%), total fat(48%), SFA(26%), and sodium(54%). One serving provided 15-23% of the reference values for calcium, potassium, and magnesium, while higher contributions were found for zinc(30%), manganese(38%), phosphorus(51%), and iron(67%). The ultra-processed plant-based burgers, provide protein, dietary fibre and essential minerals, but also contain relatively high levels of energy, sodium, and total fats. The amino acid composition of the plant-based burgers indicated low protein quality. The multifaceted nutritional profile of plant-based burgers highlights the need for manufacturers to implement improvements to better support healthy dietary habits. These improvements should include reducing energy, sodium and total fats.
- Ocorrência de micotoxinas em alimentos comercializados em PortugalPublication . Martins, Carla; Assunção, Ricardo; Pires, M.J.; Cunha, S.; Petta, T.; Jagger, A.; Oliveira, C.; Alvito, PaulaAs micotoxinas são metabolitos secundários produzidos por fungos e que causam efeitos tóxicos e cancerígenos no Homem e em animais. As micotoxinas podem contaminar vários géneros alimentícios, incluindo cereais e produtos derivados, fórmulas infantis, leite, fruta, entre outros; constituem assim, não só um problema de segurança alimentar, mas também um problema económico. O objetivo deste estudo foi determinar a incidência e os teores de 21 micotoxinas e metabolitos (AFB1, AFB2, AFG1, AFG2, AFM1, OTA, FB1, FB2, NIV, ZEA, NEO, DAS, FUS-X, DON, 15-ADON, 3-ADON, HT-2, T-2, VER, T-2 TETROL, T-2 TRIOL) em alimentos disponíveis no mercado português, e comparar os resultados com os limites máximos estabelecidos pela União Europeia. Para este estudo foram analisadas por HPLC-FLD, LC-MS/MS e GC-MS, amostras de cereais de pequeno-almoço (n=26), farinhas infantis (n=20), fórmulas infantis (n=10), bolachas (n=6) e leites UHT (n=21), num total de 83 amostras. Os resultados obtidos mostraram que 96% dos cereais de pequeno-almoço, 50% das farinhas infantis, 50% das bolachas, 40% das fórmulas infantis, e 19% dos leites UHT, estavam contaminados com micotoxinas (valores acima do limite de detecção), embora todas as amostras apresentassem níveis abaixo dos limites máximos estabelecidos no Regulamento 1881/2006 e na Recomendação 165/2013 da Comissão Europeia. A co-ocorrência de micotoxinas diferentes na mesma amostra foi também observada com elevada incidência nas amostras analisadas (92% em cereais pequeno-almoço, 70% em farinhas infantis, 50% em bolachas, 40% em fórmulas infantis, 19% em leites UHT). Estes resultados contribuem para o conhecimento sobre os teores de micotoxinas nos alimentos comercializados em Portugal e consumidos por crianças jovens, salientando assim a necessidade de uma revisão da legislação com vista à diminuição dos limites legais para micotoxinas nos cereais pequeno-almoço, à inclusão de novas combinações matriz alimentar-micotoxina, e ainda a consideração das misturas de micotoxinas nos alimentos. A última questão é particularmente importante considerando os possíveis efeitos sinérgicos que podem ocorrer entre as micotoxinas e seu potencial impacto na saúde humana e, principalmente, na saúde das crianças.
- Ocorrência de micotoxinas em alimentos para crianças comercializados em PortugalPublication . Martins, Carla; Assunção, Ricardo; Pires, M.J.; Cunha, S.; Petta, T.; Jagger, A.; Oliveira, C..; Alvito, PaulaMicotoxinas - características gerais: - são metabolitos secundários produzidos por fungos, capazes de produzir efeitos tóxicos agudos e crónicos (carcinogénicos, mutagénicos, teratogénicos, imunotóxicos e estrogénicos), em animais e humanos; - Os alimentos são susceptíveis à contaminação nas diferentes fases da colheita, produção, armazenamento ou processamento.
- Syndromes associated with children exposure to mycotoxins and health risk assessment to multiple mycotoxins in infant foodsPublication . Alvito, Paula; Martins, Carla; Assunção, Ricardo; Pires, M.J.; Calhau, Maria Antónia1. Children health and mycotoxins; 2. Routes of exposure; 3. Syndromes Syndromes associated associated with children children exposure exposure to mycotoxins: to mycotoxins: ingestion and inhalation; 4. Health risk assessment to multiple mycotoxins in infant foods -MYCOMIX project (PTDC/DTP-FTO/0417/2012); 5. Critical role of health professionals
- Trihalomethanes in liver pathology: Mitochondrial dysfunction and oxidative stress in the mousePublication . Faustino-Rocha, A.I.; Rodrigues, D.; da Costa, R.G.; Diniz, C.; Aragão, S.; Talhada, D.; Botelho, M.; Colaço, A.; Pires, M.J.; Peixoto, F.; Oliveira, P.A.Trihalomethanes (THMs) are disinfection byproducts found in chlorinated water, and are associated with several different kinds of cancer in human populations and experimental animal models. Metabolism of THMs proceeds through enzymes such as GSTT1 and CYP2E1 and gives rise to reactive intermediates, which form the basis for their toxic activities. The aim of this study was to assess the mitochondrial dysfunction caused by THMs at low levels, and the resulting hepatic histological and biochemical changes in the mouse. Male ICR mice were administered with two THMs: dibromochloromethane (DBCM) and bromodichloromethane (BDCM); once daily, by gavage, to a total of four administrations. Animals were sacrificed four weeks after DBCM and BDCM administrations. Blood biochemistry was performed for alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), total bilirubin (TB), albumin (Alb), total protein (TP), creatinine, and urea. Animals exposed to DBCM and BDCM showed elevated ALT and TB levels (p < 0.05) as compared with controls. Histological analysis confirmed the presence of vacuolar degenerescence and a multifocal necrotizing hepatitis in 33% of animals (n = 2). Mitochondrial analysis showed that THMs reduced mitochondrial bioenergetic activity (succinate dehydrogenase (SQR), cytochrome c oxidase (COX), and ATP synthase) and increased oxidative stress (glutathione S-transferase (GST)) in hepatic tissues (p < 0.05). These results add detail to the current understanding of the mechanisms underlying THM-induced toxicity, supporting the role of mitochondrial dysfunction and oxidative stress in liver toxicity caused by DBCM and BDCM. © 2015 Wiley Periodicals, Inc. Environ Toxicol, 2015.
- XIX Encontro Nacional de Ecologia 'Desafios para a Nova Década': Livro de resumosPublication . Pires, M.J.; Assunção, R.; Vasco, Elsa; Alvito, PaulaLivro de resumos do XIX Encontro Nacional de Ecologia 2020. Em 2020, as Nações Unidas nomearam este ano como início da Década do Restauro Ecológico, da Ciência para a Sustentabilidade dos Oceanos e do desenvolvimento de planos de acção para alcançar os Objectivos do Desenvolvimento Sustentável. E este início foi bem marcado por profundas alterações à nossa sustentabilidade, realçando as vulnerabilidades da actual sociedade. Há mais de 30 anos que os cientistas afirmam que o excesso de exploração de recursos, a fragmentação de habitats, o comércio ilegal de espécies, entre outros, estão a enfraquecer as barreiras naturais que protegem a nossa sobrevivência e bem-estar. Em menos de um ano, uma epidemia escalou a uma pandemia que vincará os seus efeitos durante anos. Mais do que nunca a Ecologia, enquanto ciência transversal, e os ecólogos, em particular, são chamados a intervir e a mostrar o seu papel como profissionais científicos relevantes numa sociedade em mudança. Fez por isso sentido que o XIX Encontro Nacional de Ecologia (ENE) tenha sido estruturado de forma a destacar três grandes temas: restauro e gestão ecológica, biodiversidade e ecossistemas e recursos marinhos e oceanos.