Browsing by Author "Dias, Ana Rita"
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- Antibacterial activity of ionic liquids based on betalactamantibiotics against resistant bacteriaPublication . Dias, Vitorino; Santos, Miguel; Prudêncio, Cristina; Noronha, João P.; Grilo, Inês R.; Sobral, Rita G.; Dias, Ana Rita; Branco, Luís C.; Ferraz, RicardoThe cases of antibiotic resistance are increasing and becoming more and more common, giving rise to a new problem for public health. Therefore, the discovery of new antibiotics is important and necessary.
- Bioactivity of ionic liquids based on valproate in SH-SY5Y human neuroblastoma cell linePublication . Dias, Ana Rita; Ferraz, Ricardo; Costa-Rodrigues, João; Santos, Andreia F. M.; Jacinto, Manuel L.; Prudêncio, Cristina; Noronha, João Paulo; Branco, Luís C.; Petrovsk, ŽeljkoThe search for alternative and effective therapies to fight cancer is one of the main goals of the pharmaceutical industry. Recently, ionic liquids (ILs) have emerged as potential therapeutic agents with antitumor properties. The goal of this study was to synthesize and evaluate the bioactivity of different ILs coupled with the active pharmaceutical ingredient (API) valproate (VPA) as an antitumor agent. The toxicity of the prepared ionic liquids was evaluated by the MTT cell metabolic assay in human neuroblastoma SH-SY5Y and human primary Gingival Fibroblast (GF) cell lines, in which they showed inhibitory effects during the study period. In addition, low cytotoxicity against GF cell lines was observed, suggesting that these compounds are not toxic to human cell lines. [C2OHDMiM][VPA] demonstrated an outstanding antitumor activity against SH-SY5Y and lower activity against the non-neoplastic GF line. The herein assessed compounds played an important role in the modulation of the signaling pathways involved in the cellular behavior. This work also highlights the potential of these ILs-API as possible antitumor agents.
- Book of abstracts 4th Meeting on Medicinal Biotechnology (4EBtM)Publication . Costa, Ana Rita; Dias, Ana Rita; Prudêncio, Cristina; Borges, Cristina; Teixeira, Dulce; Almeida, Joana; Vieira, Mónica; Coelho, Pedro; Ferraz, Ricardo; Cunha, SofiaThese meetings have been held once a year since 2015 and have played an important role as a point of contact among several professionals and students in Medicinal Biotechnology. Like the Medicinal Biotechnology field itself, these meetings have also been expanding, not only in the number of participants, but also in their geographical origin. Therefore, it is our goal to act as an interface between students and biotechnology companies/researchers, as well as to increasingly promote networking, projects and collaborations within this field for the upcoming years.
- Book of abstracts of the III Encontro de Biotecnologia Medicinal/ I Iberian Congress on Medicinal BiotechnologyPublication . Costa, Ana Rita; Prudêncio, Cristina; Teixeira, Dulce; Almeida, Joana; Vieira, Mónica; Coelho, Pedro; Ferraz, Ricardo; Cunha, Sofia; Dias, Ana RitaEstes encontros de Biotecnologia Medicinal iniciaram-se em 2015 e sentimos que estamos a crescer, tal como a Biotecnologia Medicinal. Esta área da Biotecnologia tem ganho relevância, quer em empresas, quer a nível académico, criando interfaces entre a biologia molecular, a microbiologia e a química medicinal.
- Ionic liquids for topical delivery in cancerPublication . Dias, Ana Rita; Costa-Rodrigues, João; Teixeira, Cátia; Gomes, Paula; Prudêncio, Cristina; Ferraz, RicardoThe unique properties of ionic liquids make them quite appealing for diverse applications, from "green" solvents (1st generation ionic liquids) to finely tuned materials (2nd generation ionic liquids). A decade ago, a 3rd generation of ionic liquids emerged which is focused on their prospective clinical applications, either as drugs per se or as adjuvants in drug formulations. In recent years, research focused on use of ionic liquids for topical drug delivery has been increasing and holds great promise towards clinical application against skin cancers. This article highlights the growing relevance of ionic liquids in medicinal chemistry and pharmaceutical technology, which is opening new windows of opportunity.
- Serine-based surfactants active against antibioticresistant bacteriaPublication . Dias, Ana Rita; Silva, Sandra G.; Prudêncio, Cristina; Gomes, Paula; Ferraz, Ricardo; Marques, Eduardo F.; Vale, M. Luísa C.Bacterial resistance to antibiotics has been a recognized reality almost since the dawn of the antibiotic era, but only within the past twenty years has the emergence of dangerous, resistant strains occurred with a disturbing regularity. As no new antibiotics have been developed in the last twenty years, existing drugs are quickly becoming ineffective.
- Serine-based surfactants as effective antimicrobial agents against multiresistant bacteriaPublication . Silva, Sandra G.; Pinheiro, Marina; Pereira, Rui; Dias, Ana Rita; Ferraz, Ricardo; Prudêncio, Cristina; Eaton, Peter J.; Reis, Salette; Vale, M. Luísa C. doThe antimicrobial activity of two serine derived gemini cationic surfactants, amide (12Ser)2CON12 and ester (12Ser)2COO12, was tested using sensitive, E. coli ATCC 25922 and S. aureus ATCC 6538, and resistant, E. coli CTX M2, E. coli TEM CTX M9 and S. aureus ATCC 6538 and S. aureus MRSA ATCC 43300 Gram-positive and Gram-negative bacteria strains. Very low MIC values (5 μM) were found for the two resistant strains E.coli TEM CTX M9 and S. aureus MRSA ATCC 43300, in the case of the amide derivative, and for S. aureus MRSA ATCC 43300, in the case of the ester derivative. The interaction of the serine amphiphiles with lipid-model membranes (DPPG and DPPC) was investigated using Langmuir monolayers. A more pronounced effect on the DPPG than on the DPPC monolayer was observed. The effect induced by the surfactants on bacteria membrane was explored by Atomic Force Microscopy. A clear disruption of the bacteria membrane was observed for E. coli TEM CTX M9 upon treatment with (12ser)2CON12, whereas for the S. aureus MRSA few observable changes in cell morphology were found after treatment with either of the two surfactants. The cytotoxicity of the two compounds was assessed by hemolysis assay on human red blood cells (RBC). The compounds were shown to be non-cytotoxic up to 10 μM. Overall, the results reveal a promising potential, in particular of the amide derivative, as antimicrobial agent for two strains of antibiotic resistant bacteria.
- Synthesis and Antibacterial Activity of Ionic Liquids and Organic Salts Based on Penicillin G and Amoxicillin hydrolysate Derivatives against Resistant BacteriaPublication . Ferraz, Ricardo; Silva, Dário; Dias, Ana Rita; Dias, Vitorino; Santos, Miguel M.; Pinheiro, Luís; Prudêncio, Cristina; Noronha, João Paulo; Petrovski, Željko; Branco, Luís C.The preparation and characterization of ionic liquids and organic salts (OSILs) that contain anionic penicillin G [secoPen] and amoxicillin [seco-Amx] hydrolysate derivatives and their in vitro antibacterial activity against sensitive and resistant Escherichiacoli and Staphylococcusaureus strains is reported. Eleven hydrolyzed β-lactam-OSILs were obtained after precipitation in moderate-to-high yields via the neutralization of the basic ammonia buffer of antibiotics with different cation hydroxide salts. The obtained minimum inhibitory concentration (MIC) data of the prepared compounds showed a relative decrease of the inhibitory concentrations (RDIC) in the order of 100 in the case of [C2OHMIM][seco-Pen] against sensitive S. aureus ATCC25923 and, most strikingly, higher than 1000 with [C16Pyr][seco-Amx] against methicillin-resistant Staphylococcus aureus (MRSA) ATCC 43300. These outstanding in vitro results showcase that a straightforward transformation of standard antibiotics into hydrolyzed organic salts can dramatically change the pharmaceutical activity of a drug, including giving rise to potent formulations of antibiotics against deadly bacteria strains.
- The Anticancer Potential of Ionic LiquidsPublication . Dias, Ana Rita; Rodrigues, João; Fernandes, Maria Helena; Ferraz, Ricardo; Prudêncio, CristinaAmong the many challenges that the pharmaceutical industry currently faces is the need to develop innovative and effective therapies. The investigation of alternative and effective therapies against cancer is a current goal of the pharmaceutical industry. Ionic liquids (ILs) have emerged recently as a topic of study by researchers in the pharmaceutical industry in their search for new therapeutic agents. By definition, ILs are organic salts with melting points below 100 °C that are composed only by ions. Their main advantage lies in the numerous possible combinations of cations and anions, which allow adjustments in their physicochemical properties. The combination between ILs and active pharmaceutical ingredients (APIs) may improve the properties of APIs. In addition, the antitumor properties of these compounds have been described. Several studies have reported the use of ILs in biomedical applications as therapeutic agents, namely as antitumor agents. This review describes the recent proposed applications of ILs as antitumor agents.