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- Ionic Liquids Synthesis – MethodologiesPublication . Ferraz, Ricardo; Prudêncio, Cristina; Vieira, Mónica; Fernandes, Rúben; Noronha, João Paulo; Petrovski, ZeljkoIonic Liquids (IL) are salts with at least one organic cation. The term “Ionic Liquid” has been restricted to salts with melting point below 100° C [1]. In the recent years, (ILs) have gained popularity in science and technology. The large number of possible cation/ anion combinations allows a great variety of tunable interactions; also their unique properties and characteristics make it a promising and an attractive to work with in several fields. However, how ILs are produced? This editorial pretends to make a brief commentary of some of the main methodologies of ILs synthesis
- New ionic liquids and salts derived from β-Lactam antibioticsPublication . Ferraz, Ricardo; Branco, Luís; Marrucho, Isabel; Fernandes, Rúben; Prudêncio, Cristina; Noronha, João Paulo; Petrovski, ZeljkoIn recent years ionic liquids (ILs) have been increasing the popularity and the number of applications. Ionic liquids were used mainly as solvent in organic synthesis, but in recent years they are also used in analytical chemistry, separation chemistry and material science. Additional to significant developments in their chemical properties and applications, ionic liquids are now bringing unexpected opportunities at the interface of chemistry with the life sciences. Ionic liquids (ILs) are currently defined as salts that are composed solely of cations and anions which melt below 100ºC. Our goal in this work is to explore the dual activity of the ionic liquids, due to the presence of two different ions, an anion with bacterial activity as β-lactam antibiotics and different kinds of cations. In this work the anions of ILs and salts were derived from three different antibiotics: ampicillin, penicillin and amoxicillin. The cations were derived from substituted ammonium, phosphonium pyridinium and methylimidazolium salts, such as: tetraethyl ammonium, trihexiltetradecilphosphonium, cetylpyridinium, choline (an essential nutrient), 1-ethyl-3-methylimidazolium, and 1-ethanol-3-methyl imidazolium structures. Commercial ammonium and phosponium halogen salts were first transformed into hydroxides on ionic exchange column (Amberlite IRA-400) in methanol. The prepared hydroxides were then neutralized with β-lactam antibiotics. After crystallization we obtained pure ILs and salts containing β-lactam antibiotics. This work presents a novel method for preparation of new salts of antibiotics with low melting point and their chemistry and microbiological characterization.
- Distúrbios alimentares – anorexia: da auto-imagem às atitudes e comportamentosPublication . Fernandes, Rúben; Reis, AC.; Esteves-Pinto, A.; Fonte, R.; Coelho, Pedro; Prudêncio, CristinaSão ainda escassos os estudos sobre distúrbios alimentares em alunos do ensino universitário em Portugal. Estudos mais recentes indicam que poderá existir uma predisposição genética para a anorexia, no entanto, os fatores ambientais são os que apresentam um papel determinante, em particular factores sócio-económicos, psicológicos, biológicos entre outros. Entre esses diversos factores, sabe-se que a auto-imagem pode relacionar-se como múltiplos distúrbios alimentares como a anorexia e bulimia.
- Ensino e aprendizagem da Bioquímica em Ciências da Saúde: retenção de conhecimentos adquiridos e sucesso académico versus tipo de exame preferido, sua preparação e stress associadoPublication . Prudêncio, Cristina; Fernandes, Rúben; Ferraz, Ricardo; Vieira, Mónica; Fonte, RosáliaNum contexto de reestruturação da formação em Ciências da Saúde baseada em competências, torna-se necessário estudar as diferentes formas de avaliação e o stress que lhe está associado, observando de que forma estas poderão interferir no sucesso académico dos alunos e real aquisição de competências. O objectivo do trabalho foi avaliar estas questões no âmbito da Bioquímica de diferentes cursos de Tecnologias da Saúde. A metodologia foi adaptada de controlled pre-test-postest, e os resultados obtidos apontam para que os alunos que mais estudam, ao longo do ano e não no “sprint final”, parecem possuir menor stress e serem melhor sucedidos.
- Quinoxaline, its derivatives and applications: A state of the art reviewPublication . Almeida, Joana; Pessoa, Ana M.; Cordeiro, M. Natália D. S.; Fernandes, Rúben; Prudêncio, Cristina; Noronha, João Paulo; Vieira, MónicaQuinoxaline derivatives are an important class of heterocycle compounds, where N replaces some carbon atoms in the ring of naphthalene. Its molecular formula is C8H6N2, formed by the fusion of two aromatic rings, benzene and pyrazine. It is rare in natural state, but their synthesis is easy to perform. In this review the State of the Art will be presented, which includes a summary of the progress made over the past years in the knowledge of the structure and mechanism of the quinoxaline and quinoxaline derivatives, associated medical and biomedical value as well as industrial value. Modifying quinoxaline structure it is possible to obtain a wide variety of biomedical applications, namely antimicrobial activities and chronic and metabolic diseases treatment.
- Potentional radiosensitizer effect of TUDCA in a obesity model of brain tumor cellsPublication . Silva, Liliana; Almeida, Joana; Coelho, Pedro; Faria, Isabel; Monteiro, Armanda; Soares, Raquel; Vieira, Mónica; Prudêncio, Cristina; Fernandes, RúbenObesity may play an important role in the biology of seve ral types of cancer, but the correlation with glioma Is still not very well defined. Former studies indicated that obesity may be related with an decreased resistance to radiation and increased redox status in brain tumors. Since radiothetapy is the most commonly treatment modality used in this type of tumor, we creale a new model of experiments to determinate the influence of obesity in glioma cells [n the presence of radiation with an imbalance of redox status, BC3H1 glioma cells were treated with t-BOOH (150~M), TUDCA (25~M) and a mix of t-BOOH and TUOCA{150~M and 25~M respectively) in serum-free OMEM or conditioned media (CM) from differentiated 3T3-L 1 adj pocytes. Afterwards the cells were irradiated with a total dose of 2 Gy. Subsequently BC3H1 viability was evaluated, by MTT assay, after 4 and 12 hours. We observed an increase in viability In all cells treated solely with 3T3-L 1 eM. Interestingly, in the presence of CM plus TUDCA or t-BOOH, the viability of 6C3H1 was inferior of TUOCA or t~BOOH treatments alone, this effect was independent of irradia tion. After 12 hours the I/iability of the glioma cells was significantly higher on irradiated ceUs treated only with eM, this effect was not yet observed at the 4 hours time point But, in the presence of mix of t~BOOH and TUDCA, with eM and irradiation the cells viability decrea se significanUy. The 3T3-L 1 Me increase (he cell viabrlity in the presence of radiation or not, after 12 hours expose" But in the presence of oxidatIve inducer and, In specially, with the antioxidant TUDCA, the BC3Hi viability significantly decrease. So, we observed a potential radiosensitfzer effect of TUDCA in BC3H1 in the presence of 3T3-L1 adipocytes.
- Determination of antimicrobial residues in milk samplesPublication . Batista, Larissa; Pais, Patrick; Fernandes, Rúben; Prudêncio, Cristina; Vieira, MónicaIn farming activities, antimicrobials are widely used as a therapeutic measure in the treatment of bacterial infections, disease prophilaxys and as a growth promoter (food additives) (Marshall & Levy, 2011). The presence of antimicrobial residues in milk may represent risks for human health, namely allergic reactions on hypersensitive individuals, or even cause problems indirectly by development of resistant strains of bacteria (Tillotson, Doern, & Blondeau, 2006).
- A hiperglicemia e o secretoma de adipócitos alteram o padrão de crescimento de micobactérias in vitroPublication . Fernandes, Rúben; Bronze, M.; Pereira, C.; Coelho, Pedro; Prudêncio, Cristina
- Fungidal and bacterial activity of N,N-dimethyl-4-(2,2,2-trichloro-1-(phenylamino)ethyl)anilinePublication . Ferraz, Ricardo; Petrovski, Zeljko; Fernandes, Rúben; Noronha, João Paulo; Prudêncio, CristinaN,N-dimethyl-4-((phenylamino)methyl)aniline (1) was prepared by condensation of aniline and 4-(dimethylamino)benzaldehyde [1] N,N-dimethyl-4-(2,2,2-trichloro-1-(phenylamino)ethyl)aniline (2) was synthesized by trichloromethylation of the imine (N,N-dimethyl-4-((phenylimino)methyl)aniline (1)) with trichloroacetic anhydride under microwave irradiation [2] (Sheme 1). The present work reports the study of bacterial and yeast activity for the compound 2. The bacteria used in this study are Staphylococcus aureus, Escherichia coli and the yeast are Saccharomyces Cerevisiae Candida albican.The results that we will present are the determination of minimal inhibitory concentration (MIC), by means of microdilution by plate method and the specific growth constants for this microorganism. Further studies are being performed to determine viability and cellular injury with this drug.
- Development of a new method for the detection and quantification of 3-nitrotyrosinePublication . Teixeira, Dulce; Prudêncio, Cristina; Fernandes, Rúben; Vieira, MónicaThe nitration of Tyrosine residues in proteins is associated with nitrosative stress, resulting in the formation of 3-nitrotyrosine (3-NT). Different methods have been described for the quantification of this molecule. Regarding chromatographic methods, they seem to be very accurate, showing very good sensibility and specificity. Gas chromatography-based methods exhibit the highest sensibility, however a derivatization step prior analysis is required, which ends up being time-consuming for the analyst. Conversely, High Performance Liquid Chromatography (HPLC) may not require such derivatization.