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- Usos populares de plantas medicinais da flora transmontanaPublication . Neves, José Manuel Gomes da Silva; Matos, Carla; Moutinho, Carla; Gomes, Lígia RebeloNeste trabalho é apresentado um estudo sobre o uso tradicional das plantas medicinais de dois concelhos da região de Trás-os-Montes. Durante o estudo, foram obtidos resultados relativos às plantas com maior uso medicinal e suas aplicações terapêuticas bem como as partes da planta mais usadas de 88 espécies pertencentes a 47 famílias de plantas indígenas. As propriedades terapêuticas mais referenciadas são os efeitos diurético, antiasténico e como vulnerário. Partindo de um relatório etnofarmacológico de várias plantas serão, posteriormente, seleccionadas aquelas que, tendo larga aplicação na medicina tradicional, não tenham sido estudadas do ponto de vista bioquímico e de actividade terapêutica. In this work a study of folk use of the medicinal plants of two councils bellowing to Trás-os-Montes region is presented. During the study, data for 88 species were obtained belonging to 47 families of vascular plants. The most report therapeutic properties are as diuretic, as anti-asthenia and as vulnerary. From an ethnopharmacological report done, will be subsequently selected those plants that, having, not only, a wide range of usage in traditional medicine but also, have not yet been studied in biochemical or therapeutic activity terms.
- The synthesis, crystal structure and Hirshfeld analysis of 4-(3,4-dimethylanilino)-N-(3,4-dimethylphenyl)quinoline-3-carboxamidePublication . Gomes, Lígia Rebelo; Low, John Nicolson; Borges, Fernanda; Gaspar, Alexandra; Mesiti, FrancescoThe structure of the title quinoline carboxamide derivative, C26H25N3O, is described. The quinoline moiety is not planar as a result of a slight puckering of the pyridine ring. The secondary amine has a slightly pyramidal geometry, certainly not planar. Both intra- and intermolecular hydrogen bonds are present. Hirshfeld surface analysis and lattice energies were used to investigate the intermolecular interactions.
- Structural and electronic effects of the C2’ substituent in 1,4–benzodiazepinesPublication . Gomes, Lígia Rebelo; Santos, Luís Manuel Neves Belchior Faia; Beleza, José; Low, John Nicolson; yesBenzodiazepines are drugs used for treatment of several central nervous system disorders, such as anxiety and sleep. In spite of their wide and popular usage in clinics, the mechanism explaining why a certain pharmacological activity is superimposed onto another for a given benzodiazepine remains unclear. The knowledge of the conformation of benzodiazepines and their electronic charge distribution at molecular surfaces may give new insights into the pharmaco‐benzodiazepine receptor interactions, contributing to the improvement of the existing models. In the present study, the solid state geometric and conformational parameters of the available X‐ray benzodiazepine structures were analyzed and reviewed. The electronic features of two groups of benzodiazepines with different substituents at C7 and C2’ positions were studied by DFT quantum chemical calculations. The conformations of the molecules with optimized geometry were also analyzed. The relative charge distribution around the benzodiazepinic rings and electrostatic potential mapped on electronic density surfaces were obtained. The ring geometric parameters for the diazepine moiety in 1,4‐ benzodiazepines, do not vary significantly except for a few compounds in which steric and/or intermolecular interactions play a part. The benzodiazepine ring assumes a pseudosymmetrical boat conformation and the torsion angle around the C5‐Ph bond varies depending on the nature of the substituent on C2’. Also, the presence of the nitro or chloride substituent on the C7 position and the presence of a fluorine atom on the C2’ position significantly alter the relative charge distributions at the attached carbon atoms and the topology of the surface electrostatic potential.
- 4,4′-(1,8-Naphthalene-1,8-diyl)dibenzonitrilePublication . Lima, Carlos F.; Gomes, Ligia R.; Santos, Luís M. N. B. F.; Low, John NicolsonIn the title mol-ecule, C(24)H(14)N(2), the exterior C-C-C angle of the naphthalene ring system involving the two phenyl-substituted C atoms is 126.06 (11)° and the dihedral angles between the mean plane of the naphthalene ring system and those of the benzene rings are 66.63 (5) and 67.89 (5)°. In the crystal, mol-ecules are linked into a ladders by four weak C-H⋯π inter-actions.
- Effect of extraction methodology on the phytochemical composition for camelia sinensis “Powdered tea extracts” from different provenancesPublication . Barreira, Sérgio; Silva, André M. N.; Moutinho, Carla; Seo, Ean-Jeong; Hegazy, Mohamed-Elamir F.; Efferth, Thomas; Gomes, Lígia RebeloBackground: beverages based on extracts from Camellia sinensis are popular worldwide. Due to an increasing number of processed teas on the market, there is a need to develop unified classification standards based on chemical analysis. Meanwhile, phytochemical characterizations are mainly performed on tea samples from China (~80%). Hence, data on teas of other provenances is recommended. (2) Methods: in the present investigation, we characterized lyophilised extracts obtained by infusion, maceration and methanolic extraction derived from tea samples from China, Japan, Sri Lanka and Portugal by phytochemistry (catechins, oxyaromatic acids, flavonols, alkaloids and theanine). The real benefits of drinking the tea were analysed based on the bioavailability of the determined phytochemicals. (3) Results: the infusions revealed the highest total phenolic contents (TPC) amounts, while methanolic extracts yielded the lowest. The correlation matrix indicated that the levels of phenolic compounds were similar in the infusions and methanolic samples, while extractions made by maceration were significantly different. The differences could be partially explained by the different amounts of (-)-epigallocatechin gallate (EGCG), (-)-epicatechin gallate (ECG) and gallic acids (GA). The catechin percentages were significantly lower in the macerations, especially the quantity of EGCG decreases by 4- to 5-fold after this process. (4) Conclusions: the results highlight the importance of the processing methodology to obtain “instant tea”; the composition of the extracts obtained with the same methodology is not significantly affected by the provenance of the tea. However, attention should be drawn to the specificities of the Japanese samples (the tea analysed in the present work was of Sencha quality). In contrast, the extraction methodology significantly affects the phytochemical composition, especially concerning the content of polyphenols. As such, our results indicate that instant tea classification based on chemical composition is sensible, but there is a need for a standard extraction methodology, namely concerning the temperature and time of contact of the tea leaves with the extraction solvent.
- Antispasmodic activity of aqueous extracts from Mentha x piperita native from Trás-os-Montes region (Portugal)Publication . Moutinho, Carla; Matos, Carla; José Manuel, Neves; Teixeira, Dora Martins; Cunha, Sílvia; Gomes, Lígia RebeloThe wild mint Mentha x piperita (Mentha rotundifolia Huds.), has been used by the local people in a northern region of Portugal to prepare infusions for treating digestive pain and spasms, as an appetite stimulant and for treating headache and migraine. This suggests that these aqueous extracts have analgesic; antispasmodic and stomachic properties. In the present study the antioxidant potential of aqueous extracts of Mentha x piperita is investigated since natural antioxidants can scavenge the reactive oxygen species, ROS, and thus might attenuate inflammation pathways. The antispasmodic activity was also checked. The antioxidant potential of the extract was evaluated by the DPPH• method, by the quantification of the total phenolic compounds and by characterization of the main phenolic compounds. The antispasmodic effects were investigated by performing pharmacological assays using the distal ileum of guinea pigs. The aqueous extract exhibits antioxidant properties that may be due to its phenolic content. The main phenolic compounds were quinic, caffeic, rosmarinic and chlorogenic acids. The antispasmodic affects are observed after electrical stimulation of segments of distal ileum of guinea pigs and may be attributed, at least, to a alfa-1 blockage.
- Actividade antioxidante e avaliação in vitro da citotoxicidade de extractos aquosos de folhas de mentha x piperitaPublication . Neves, José Manuel Gomes da Silva; Matos, Carla; Moutinho, Carla; Gomes, Lígia Rebelo; Teixeira, TâniaNeste estudo apresentam-se os resultados referentes à avaliação do potencial anti-oxidante de extractos aquosos de Menta x piperita recolhida da região de trás-os-montes. A capacidade anti-oxidante foi testada pelo método DppH•, tendo sido também feita a quantificação dos compostos fenólicos totais nos extractos pelo método de Folin-ciocalteu, apontados como os responsáveis pelas propriedades antioxidantes da planta. Adicionalmente, apresentam- se os resultados relativos à avaliação citotoxicidade dos mesmos extractos através de testes de citotoxicidade in vitro, utilizando como organismo modelo tetrahymena pyriformis (com viabilidade avaliada pelo ensaio colorimétrico mtt). The aim of the present study is to investigate the antioxidant potential of aqueous extracts of Menta x piperita from trás-os-montes by the DppH• method, as well as to quantify the total phenolic compounds in the extracts by the Folin-ciocalteu method, probably responsible for the plant antioxidant properties. Additionally, the research work presented herein seeks to assess the effects of Menta x piperita through a series of in vitro cytotoxicity tests, using tetrahymena pyriformis as model organism. Viability will be evaluated by the colorimetric mtt assay.
- Biofísica e meios complementares de diagnóstico: caderno de elementos para o estudo orientadoPublication . Gomes, Lígia Rebelo; Silva, Maria RaquelEste caderno pretende, tal como o nome indica, apoiar o estudo dos estudantes do 1º Ciclo de Estudos (Licenciatura) em Enfermagem, na Escola Superior de Saúde Fernando Pessoa. Encontra-se organizado, de forma a respeitar uma lógica metodológica na apresentação dos conteúdos, que vão desde as ferramentas matemáticas que suportam a Biofísica, passando pelos meios complementares de diagnóstico e imagiologia médica, os modelos das membranas biológicas e fenómenos de transporte, a regulação, controlo e homeotermia, e terminando, na dinâmica de fluidos e a circulação sanguínea. O motivo da escolha e da apresentação destes conteúdos baseou-se na necessidade de responder às exigências curriculares dos estudantes de Enfermagem, centrando o seu estudo da Biofísica na aplicação em meio clínico, com vista a sua operacionalização no doente, aquando do diagnóstico de eventuais doenças, e respetivo seguimento, durante o tratamento, e potencial pós-tratamento.
- Structural study of three heteroaryl oximes, heteroaryl-N=OH: Compounds forming strong C3 molecular chainsPublication . Low, John Nicolson; Wardell, James Lewis; Da Costa, Cristiane Franca; Souza, Marcus Vicinius Nora; Gomes, Lígia RebeloIn order to further investigate the structural chemistry of oximes and to further establish the main structural arrangements adopted, we have determined the crystal structure of and carried out Hirshfeld surface calculations on three heteroaryl oximes, namely (Z)-thiophene2-carbaldehyde oxime (1), (Z)-1H-pyrrole-2 carbaldehyde oxime (2) and (Z)-5-nitrofuran-2- carbaldehyde oxime (3). As confirmed by both techniques, the major intermolecular interactions in each compound are classical N—H···O hydrogen bonds, which link the molecules into C3 chains. Such an arrangement has been previous reported as an important aggregation mode for oximes. Secondary interactions, C—H···π and C—H···O interactions, in compounds 1 and 2, and interactions involving the nitro group oxygen atoms in compound 3 link the chains into three dimensional arrays.
- Perfluorocarbon compounds used as oxygen carriers: from liquid ventilation to blood substitutesPublication . Gomes, Lígia Rebelo; Gomes, Eva RebeloPerfluorocarbon compounds are fluorine substituted hydrocarbons. They exhibit unique properties due to the specificity of the carbon –fluorine linkage. Among these, the high gas solubility and the low surface tension are the most interesting characteristics for their use in clinic. There are several biological fields of potential applications of perfluorocarbons. Concerning the clinical applications for perfluorocarbons, they have been used as gas carriers and for liquid ventilation. Several clinical trials for commercial pharmaceutics of perfluorcarbon based on these compounds have been also already made.
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