I. Componente Universitária
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- 1,1-Bis(Phenylseleno)-and 1,1-Bis(Methylseleno)- alkyllithiums as building-blocks in organic synthesisPublication . Vanende, D.; Cravador, A.; Krief, A.1,1 - Bis(phenylseleno)alkyllithiums are conveniently prepared from the corresponding selenoacetals and lithium tetramethylpiperidide in HMPT/THF.
- 1,2,4-Trioxolane and 1,2,4,5-Tetraoxane endoperoxides against old-world Leishmania parasites: in vitro activity and mode of actionPublication . Mendes, Andreia; Armada, Ana; Cabral, Lília; Amado, Patrícia; Campino, Lenea; Cristiano, Maria de Lurdes; Cortes, SofiaLeishmaniasis remains one of the ten Neglected Tropical Diseases with significant morbidity and mortality in humans. Current treatment of visceral leishmaniasis is difficult due to a lack of effective, non-toxic, and non-extensive medications. This study aimed to evaluate the selectivity of 12 synthetic endoperoxides (1,2,4-trioxolanes; 1,2,4,5-tetraoxanes) and uncover their biochemical effects on Leishmania parasites responsible for visceral leishmaniasis. The compounds were screened for in vitro activity against L. infantum and L. donovani and for cytotoxicity in two monocytic cell lines (J774A.1 and THP-1) using the methyl thiazol tetrazolium assay. Reactive oxygen species formation, apoptosis, and mitochondrial impairment were measured by flow cytometry. The compounds exhibited fair to moderate anti-proliferative activity against promastigotes of the 2 Leishmania species, with IC50 values ranging from 13.0 ± 1.7 µM to 793.0 ± 37.2 µM. Tetraoxanes LC132 and LC138 demonstrated good leishmanicidal activity on L. infantum amastigotes (IC50 13.2 ± 5.2 and 23.9 ± 2.7 µM) with low cytotoxicity in mammalian cells (SIs 22.1 and 118.6), indicating selectivity towards the parasite. Furthermore, LC138 was able to induce late apoptosis and dose-dependent oxidative stress without affecting mithocondria. Compounds LC132 and LC138 can be further explored as potential antileishmanial chemotypes.
- 1-Methylcyclopropene and lemongrass essential oil nanocoatings effect on the preservation of cold stored ‘Rocha’ pearPublication . Gago, Custódia; Guerreiro, Adriana; Cruz, Sandra; Martins, Nuno; Cabrita, Maria João; Miguel, Maria; Faleiro, Maria Leonor; Antunes, Maria DulceThe effects of coating 'Rocha' pear with alginate-based nanoemulsions enriched with lemongrass essential oil (LG) was evaluated and compared to the usual 1-MCP treatment. Fruit were treated with 1-MCP (312 nL L-1) or coated with nanoemulsions: sodium alginate 2 % (w/w) + lemongrass essential oil 1.25 % (w/w) (LG 1.25 %) or lemongrass essential oil 2.5 % (w/w) (LG 2.5 %). Then, fruit were stored at 0 degrees C and 90-95 % relative humidity (RH), for eight months. Fruit samples were collected at harvest and after two, four, six and eight months of cold storage, and then transferred to shelf-life at 22 degrees C. Upon removal and after 7 d shelf-life, fruit symptoms of superficial scald and internal browning, ethylene production, color CIE (L*, hue), firmness, soluble solids content (SSC), titratable acidity (TA), weight loss, electrolytic leakage (EL), antioxidant activity and fatty acids of pear peel, microbial growth and sensory analyses were evaluated. Coatings and 1-MCP reduced fruit color evolution and preserved better firmness than control. Coatings and 1-MCP did not affect SSC and TA. Treatments did not influence the sensory quality. Microbial growth was within the safety limits in all treatments. Treatments with 1-MCP and LG-nanoemulsions were similarly efficient to reduce superficial scald, nevertheless the LG-nanoemulsions showed higher internal disorders after 8 months of storage and LG 2.5 % had higher decay at the same period, similar to control. 1-MCP treated fruit had the lowest softening rate after shelf-life up to 4 months and LG 2.5 % showed higher weight loss. Also, ethylene production was higher in control and LG 1.25 % up to 6 months plus shelf-life, while after 8 months there was no difference among treatments. This study suggests that 1-MCP is the most efficient for preserving quality of 'Rocha' pear for 8 months, while up to 6 months the best effect is obtained with LG 1.25 % nanocoatings.
- 10 Anos da Medievalista: as revistas de ciências sociais e os seus desafiosPublication . Sousa, Bernardo Vasconcelos e; Oliveira, Luís FilipeNo dia 25 de Setembro de 2015, teve lugar na FCSH-UNL, o seminário Internacional "As Revistas de Ciências Sociais e os seus Desafios", para assinalar os dez anos de publicação ininterrupta da Medievalista OnLine. Tal como constava no desdobrável de divulgação, pretendia-se que a iniciativa fosse mais do que uma celebração e criasse a oportunidade para se fazer um balanço crítico, reflectindo “em conjunto com outras revistas, sobre os problemas e os desafios que hoje se colocam às publicações periódicas na área da História e das Ciências Sociais”.
- 100 anos da revista OrpheuPublication . Carmo, Carina Infante doNeste artigo revê-se dos aspectos mais significativos protagonizados pela revista Orpheu, no quadro da modernidade literária e política, e seus impactos mais relevantes na literatura portuguesa subsequente.
- 108P PICTuRE: Real-world treatment pathways in stage III non-small cell lung cancer in PortugalPublication . Teixeira, M.E.; Oliveira Fernandes, M.G.; Ferreira, M.L.S.; Estevinho, F.; Lopes, J.A.; Araújo, A.; Pacheco Figueiredo, M.M.; Barradas Lopes, M.L.; Lopes, M.; Brito, U.; Barroso, A.M.P.; Camacho, C.; Parente, B.; Felizardo, M.M.; Meleiro, A.; Bernardo, M.; Bernardo, F.; Figueiredo, S.Stage III NSCLC is a heterogeneous and complex setting that requires multimodal management. Recent advances in modern medicine led to the implementation of immuno-oncology (IO) into clinical practice. PICTuRE aims to assess the clinical management and the IO impact on clinical outcomes in stage III NSCLC patients (pts).
- 1867/8: a odisseia submarina de Jules VernePublication . Carvalho, Ana Alexandra Seabra deDe todos os escritores franceses, Jules Verne será talvez o mais conhecido e reconhecido fora do seu país. Pai – com H. G. Wells – da ficção científica, segundo uns; ou mero autor de livros para a juventude, segundo outros, ele revela-se, na verdade, um mestre da narrativa de aventuras, de divulgação científica e de antecipação. Neste estudo, começaremos por uma síntese dos aspetos principais da sua vastíssima obra; em seguida, recordaremos um dos seus mais afamados romances: Vinte Mil Léguas Submarinas.
- A 1ª. República na intervenção sonâmbula de José Gomes FerreiraPublication . Carmo, Carina Infante doReveladora de uma forte consciência histórica, a obra autobiográfica de José Gomes Ferreira (1900-1985) elege I República como matriz do século XX português, ciente, em todo o caso, que lhe cabe sobretudo escrever «para a eternidade efémera da História dos Momentos Ignorados». Em A Memória das Palavras (1965) e Revolução Necessária (1975), é particularmente notória a forma como situa a raiz do fascínio revolucionário no espaço nacional e lisboeta da sua aprendizagem infantil, em detrimento do exemplo mais previsível, a Revolução Russa de 1917. Dessa forma assume a filiação jacobina das barricadas, sedimentada nas leituras literárias do romantismo social e na admiração pelo pai, que foi político republicano e maçónico empenhado. Ao fazer da História matéria autobiográfica, José Gomes Ferreira não apenas recorta a formação pessoal dentro da história familiar e colectiva. Também alinha deliberadamente na valorização ideológica da I República e, por extensão, do liberalismo oitocentista levada a cabo, desde os anos 40, no campo da Historiografia e dos Estudos Literários, para responder ao anátema lançado pelo salazarismo sobre esses períodos históricos. Gomes Ferreira exerce, portanto, a resistência no campo cultural por meio do exercício de memória na primeira pessoa. Quando chega o 25 de Abril (a que chama II República), tempera o entusiasmo de o viver com a lucidez da sua já longa viagem pelo século, sempre à espera de voltar a presenciar a vibração livre da multidão nas ruas. Pressente o esquecimento progressivo da I República em benefício de um novo marco revolucionário, sabendo-se testemunha exaltada e melancólica de revoluções, da sua força construtiva e dos seus desfechos magoados.
- 1st METECH workshop – From deep-sea to coastal zones: Methods and Techniques for studying PalaeoenvironmentsPublication . Veiga-Pires, Cristina; Guillaume St-OngeReconstructing past climate and past ocean circulation demands the highest possible precision and accuracy which urges the scientific community to look at different sediment records such as the ones from coastal zones to deep-sea with a more complete set of technical and methodological tools. However, the information given by each tool varies in precision, accuracy and in significance according to their environmental settings. It is therefore essential to compare tools. With that in mind, and as part of the International year of Planet Earth, a workshop entitled `From deep-sea to coastal zones: Methods and Techniques for studying palaeoenvironments' took place in Faro (Portugal), from 25–29 February 2008.
- 2-D difference gel electrophoresis approach to assess protein expression profiles in Bathymodiolus azoricus from Mid-Atlantic Ridge hydrothermal ventsPublication . Company, Rui; Antúnez, Oreto; Bebianno, Maria João; Cajaraville, Miren P.; Torreblanca, AmparoHydrothermal vent mussels Bathymodiolus azoricus are naturally exposed to toxic chemical species originated directly from vent chimneys. The amount of toxic elements varies significantly among vent sites along the Mid-Atlantic Ridge and B. azoricus must be able to adapt to changes in hydrothermal fluid composition, temperature and pressure. The aim of this work was to study changes in the proteome in the "gill-bacteria complex" of mussels B. azoricus from three hydrothermal vent sites with distinct environmental characteristics using 2-D Fluorescence Difference Gel Electrophoresis (2-D DIGE). Results showed that 31 proteins had different expression profiles among vent sites and both cluster and principal component analysis confirm a clear separation of mussels between sites. This suggests the existence of specific parameters grouping individuals from the same hydrothermal site. Protein spots of the more abundant differentially expressed proteins were excised, digested with trypsin and identified by mass spectrometry. All identified proteins (actin, ubiquinone, S-adenosylhomocysteine hydrolase, cysteine peptidases, chaperonin and catalase) have been related previously with oxidative stress conditions and are known to be affected by ROS inducing stressors, including metals. Results point out to specific adaptations at the proteome level of B. azoricus depending on the level of toxicants present in their environment.