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- Ionic Liquids Synthesis â MethodologiesPublication . Ferraz, Ricardo; PrudĂȘncio, Cristina; Vieira, MĂłnica; Fernandes, RĂșben; Noronha, JoĂŁo Paulo; Petrovski, ZeljkoIonic Liquids (IL) are salts with at least one organic cation. The term âIonic Liquidâ 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
- Antitumor Activity of Ionic Liquids Based on AmpicillinPublication . Ferraz, Ricardo; Costa-Rodrigues, Joao; Fernandes, Maria H.; Santos, Miguel M.; Marrucho, Isabel M.; Rebelo, LuĂs Paulo N.; PrudĂȘncio, Cristina; Noronha, JoĂŁo Paulo; Petrovski, Ćœeljko; Branco, LuĂs C.Significant antiproliferative effects against various tumor cell lines were observed with novel ampicillin salts as ionic liquids. The combination of anionic ampicillin with appropriate ammonium, imidazolium, phosphonium, and pyridinium cations yielded active pharmaceutical ingredient ionic liquids (API-ILs) that show potent antiproliferative activities against five different human cancer cell lines: T47D (breast), PC3 (prostate), HepG2 (liver), MG63 (osteosarcoma), and RKO (colon). Some API-ILs showed IC50 values between 5 and 42â nm, activities that stand in dramatic contrast to the negligible cytotoxic activity level shown by the ampicillin sodium salt. Moreover, very low cytotoxicity against two primary cell linesâskin (SF) and gingival fibroblasts (GF)âindicates that the majority of these API-ILs are nontoxic to normal human cell lines. The most promising combination of antitumor activity and low toxicity toward healthy cells was observed for the 1-hydroxyethyl-3-methylimidazoliumâampicillin pair ([C2OHMIM][Amp]), making this the most suitable lead API-IL for future studies.
- New ionic liquids and salts derived from ÎČ-Lactam antibioticsPublication . Ferraz, Ricardo; Branco, LuĂs; Marrucho, Isabel; Fernandes, RĂșben; PrudĂȘncio, Cristina; Noronha, JoĂŁo 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 100ÂșC. 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 ÎČ-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 ÎČ-lactam antibiotics. After crystallization we obtained pure ILs and salts containing ÎČ-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.
- Diabetic neuropathy and oxidative stress: a systematic review focused on oxidative stress biomarkers analysisPublication . Cunha, Sofia; Nascimento, Ana Paula; Vieira, MĂłnica; PrudĂȘncio, CristinaDiabetic neuropathy is a worldwide disease with great impact in modern society. Diabetes may lead to the overproduction of reactive oxygen species, resulting in an imbalance in bodyâs redox homeostasis. Oxidative stress is pointed as an important phenomenon associated with several disease states, including diabetic neuropathy.
- Childhood depression in a portuguese sample: towards an emerging prevention programPublication . Correia, Liliana; Gianformaggio, Rafael; Douglas, Kissungo; Teixeira, Ricardo J.; PrudĂȘncio, CristinaDepression can be defined as a constant shifting of oneâs humor. Childrenâs depression results from the interaction between environmental variables and genetic predisposition factors. Depression has increased notably in the past century in this population. In Portugal, data concerning depression in children are very scarce.
- Estudo de novos compostos sintĂ©ticos para o tratamento do cancro da mamaPublication . MagalhĂŁes, Ăngela; Vieira, Filipa Quintela; Vieira, MĂłnica; Ferraz, Ricardo; PrudĂȘncio, Cristina; JerĂłnimo, Carmen; Silva, ReginaO cancro da mama (CaM) apesar dos avanços no tratamento e deteção precoce desta neoplasia, permanece como uma das principais causas de morte por cancro nas mulheres devido Ă progressĂŁo e disseminação sistĂ©mica. Cerca de 80% dos CaM invasivos sĂŁo positivos para o recetor de estrogĂ©nios sendo candidatos Ă terapia de bloqueio. No entanto, 30- 40% das doentes desenvolvem recidiva, evoluindo para um fenĂłtipo hormono-resistente. Nestes estadios, as opçÔes terapĂȘuticas apresentam uma reduzida eficĂĄcia. Assim, Ă© importante a descoberta de novos agentes anti-neoplĂĄsicos. Os lĂquidos iĂłnicos e as quinoxalinas sĂŁo sais orgĂąnicos com potencial anti-tumoral que tĂȘm vindo a ser alvo de estudo na indĂșstria farmacĂȘutica devido Ă s suas propriedades medicinais e composição flexĂvel no caso dos lĂquidos iĂłnicos.
- DistĂșrbios alimentares â anorexia: da auto-imagem Ă s atitudes e comportamentosPublication . Fernandes, RĂșben; Reis, AC.; Esteves-Pinto, A.; Fonte, R.; Coelho, Pedro; PrudĂȘncio, CristinaSĂŁo ainda escassos os estudos sobre distĂșrbios alimentares em alunos do ensino universitĂĄrio em Portugal. Estudos mais recentes indicam que poderĂĄ existir uma predisposição genĂ©tica para a anorexia, no entanto, os fatores ambientais sĂŁo os que apresentam um papel determinante, em particular factores sĂłcio-econĂłmicos, psicolĂłgicos, biolĂłgicos entre outros. Entre esses diversos factores, sabe-se que a auto-imagem pode relacionar-se como mĂșltiplos distĂșrbios alimentares como a anorexia e bulimia.
- Ensino e aprendizagem da BioquĂmica em CiĂȘncias da SaĂșde: retenção de conhecimentos adquiridos e sucesso acadĂ©mico versus tipo de exame preferido, sua preparação e stress associadoPublication . PrudĂȘncio, Cristina; Fernandes, RĂșben; Ferraz, Ricardo; Vieira, MĂłnica; Fonte, RosĂĄliaNum contexto de reestruturação da formação em CiĂȘncias da SaĂșde baseada em competĂȘncias, torna-se necessĂĄrio estudar as diferentes formas de avaliação e o stress que lhe estĂĄ associado, observando de que forma estas poderĂŁo interferir no sucesso acadĂ©mico dos alunos e real aquisição de competĂȘncias. O objectivo do trabalho foi avaliar estas questĂ”es no Ăąmbito da BioquĂmica de diferentes cursos de Tecnologias da SaĂșde. 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 nĂŁo no âsprint finalâ, 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. NatĂĄlia D. S.; Fernandes, RĂșben; PrudĂȘncio, Cristina; Noronha, JoĂŁo Paulo; Vieira, MĂłnicaQuinoxaline 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.
- The effect of high concentrations of vitamin C on a H2O2 - oxidative stress induced yeast modelPublication . Costa, Ana Rita; Cunha, Sofia; Nascimento, Ana Paula; Vieira, MĂłnica; PrudĂȘncio, CristinaNowadays, the ageing of population is conducting to a rise in the number of individuals with age-related illnesses, in which neurodegenerative diseases (ND) are included. Regardless of many variations in etiology and diverse mechanisms of cell injury, most of ND share high levels of oxidative stress, which have been highly referred not only as an underlying factor, but also as a feature. Thus, an actual challenge is to evaluate the role of antioxidants on oxidative stress states and evaluate the magnitude of possible therapeutic effects of these agents. In the present study, the toxic effect of hydrogen peroxide (H2O2) and the antioxidative function of vitamin C were investigated using Saccharomyces cerevisiae as a model. Results were achieved by exposing the yeast model to different concentrations of H2O2 and vitamin C, itself or combined, and colony forming units counting after 48 h incubation at 30ÂșC in Yeast Extract Peptone Dextrose agar plates. The results demonstrated that H2O2 exposure decreased yeast cells viability in a dose-dependent manner and that, at an optimal concentration, vitamin C was able to revert its effects. These results improved the understanding of the reversal effect of antioxidant treatment and, therefore, may be helpful on providing insights on a natural antioxidant-based therapy for ND.