ESS - CQB - Comunicações em eventos científicos
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- Goji berries (Lycium barbarum) extract as new potential cosmetic ingredient – A first screeningPublication . Silva, Joana; Teixeira, Filipa; Silva, Ana M.; Vieira, Mónica; Amaral, M. Helena; Rodrigues, Francisca; Vieira, MónicaCurrently there is greater concern about appearance and skin care products. Although cosmetic products are not associated with serious health problems, there are concerns related to undesirable effects due to the presence of potentially carcinogenic and allergenic ingredients. Thus, consumers have been increasingly looking for products of natural and plant-based origin. The use of these products is expected to increase exponentially, and studies are urgently needed to introduce new products into the market. Goji berry is a fruit with increasing popularity due to its richness in phenolic compounds, carotenoids, organic acids, carbohydrates, and vitamins. Its antioxidant, antimicrobial and anticancer activities make this product promising for cosmetic applications. The aim of this study was to study an ecological extract obtained from goji berries through ultrasound-assisted extraction as a new ingredient incorporated into a cosmetic formulation. Goji berry extract was obtained by ultrasound-assisted extraction, according to Silva et al. . To assess safety, in vitro assays were carried out on skin cell lines. Subsequently, several cosmetic formulations incorporating the extract were developed and characterized. The results demonstrated that goji berries have no toxicity on skin cell lines. Cosmetic formulations containing the goji berries extract demonstrated to be suitable for application to the skin and maintained their characteristics during the storage period. Goji berries extract is safe and stable in cosmetic formulations, proving to be suitable for consumer needs.
- Phagetherapies for infections caused by P. aeruginosaPublication . Ferraz, Ricardo; Reis, Ana; Prudêncio, Cristina; Baylina, Pilar; Fernandes, Rúben; Ferraz, Ricardo; Prudêncio, Cristina; BAYLINA MACHADO, PILAR; Fernandes, RúbenThe hospital infections can be prevented by controlling some factors related with staff, material, and environment. At this moment the existing legislation regulates procedures that prevent the propagation of the infection and/or of the agents that causes it. The Pseudomonas aeruginosa is a gram-negative opportunistic responsible for most of the hospital infections. Because it is opportunistic it is more frequent in immunocompromised patients submitted to transplants and surgical interventions. In short, this thesis has contributed for the understanding of the biology of P. aeruginosa , antibacterial treatment and its resistance to this treatment by using efflux bombs, and so as establishing associations with others factors, such as biochemical. This study has the objective to understand the resistance factors used by the P. aeruginosa in order to develop alternative therapies for this agent. Initially, 72 hospitalar isolated were characterized and 91.67% have revealed more than 3 classes of Antimicrobians.
- In vivo activity of peptide-ionic liquid conjugates against diabetic woundsPublication . Gomes, A.; Ferraz, Ricardo; Ferreira, M.; Maciel, J.; Plácido, A.; Leal, E.; Gameiro, P.; Gonçalves, Teresa; Carvalho, E.; Gomes, P.Due to widespread multidrug-resistant (MDR) microbes, efficient treatments for infected wounds are being exhausted, which means that there is an alarming lack of effective antibiotics to treat diabetic foot ulcers (DFU). The increasing life expectancy of the population and the growing incidence of unhealthy lifestyles is leading to a concerning rise in the number of people affected with diabetes and related complications, being DFU amongst the most troublesome. In 2014, already about 11% of the Portuguese population had diabetes and this number is continuously growing every year. [1] Like other chronic wounds, DFU are difficult to heal, but their association with other diabetes complications, such as peripheral neuropathy and ischemia, underpin an exceedingly low healing rate and high propensity for persistent infections. In connection with the above, we have recently advanced peptide-ionic liquid conjugates (PILC) as potential active pharmaceutical ingredients for topical formulations to tackle DFU. PILC combine a short cosmeceutical peptide with collagenboosting action, with an ioni q b , k “ k” -catalyzed azide-alkyne cycloaddition reaction. This revealed one conjugate with an outstanding performance in vitro, namely, potent collagen-inducing effect, alongside microbicidal (bactericidal and fungicidal) action.[2] This conjugate was now tested for its wound healing ability in a mouse model of streptozotocin (STZ)-induced type 1 diabetes. The promising results obtained thus far in this animal model, alongside biophysical investigations on the potential antimicrobial mechanism of action of PILC, will be presented in this communication.
- Surface-active ionic liquids derived from antimalarial drugs and natural lipids that display multi-stage antiplasmodial activityPublication . Ferraz, Ricardo; Silva, Ana Teresa; Oliveira, Isabel S.; Duarte, Denise; Moita, Diana; Nogueira, Fátima; Prudêncio, Miguel; Gomes, Paula; Marques, Eduardo F.The use of Ionic Liquids (ILs) in Medicinal and Pharmaceutical Chemistry has been greatly evolving since they were first used as alternative solvents for the chemical synthesis of active pharmaceutical ingredients (APIs). ILs are now used with other purposes in this area, such as adjuvants in drug formulation and delivery, or even as bioactive compounds per se. New ionic structures with biologically relevant properties can be easily obtained through straightforward reactions, as nearly all APIs are ionizable and can be paired with counter-ions that could be either inert or offer additional beneficial biological effects. This efficient, cost-effective strategy for the rescuing and repurposing of drugs is particularly appealing for finding new options to combat "diseases of poverty" like malaria. We implemented this approach to “recycle” classical antimalarial aminoquinolines, namely, chloroquine (CQ) and primaquine (PQ), by pairing them with natural acidic lipids through acid-base reactions. Our goal was to create novel ILs capable of targeting multiple stages of the Plasmodium parasite’s life cycle. Additionally, we were interested in that such ILs could act as surface-active ionic liquids (SAILs), able to self-assemble into nanostructures displaying adequate bioavailability. For this purpose, we paired the antimalarial drugs with either fatty acids or bile acids, due to their biocompatibility and amphiphilic nature. The antiplasmodial activity and self-aggregation properties of the new SAILs were determined. PQ fatty acid salts preserved the liver-stage antiplasmodial activity of the original drug, while exhibiting significantly enhanced activity against blood-stage parasites. In the case of bile salts, those derived from PQ retained the efficacy of the parent drug, whereas the CQ-derived salts proved to be novel triple-stage antiplasmodial agents. The SAILs obtained from bile acids showed a remarkable ability to self-aggregate, with a notably lower critical micelle concentration compared to their respective sodium salts. Overall, these findings open a new strategy for drug repurposing, extending beyond antimalarials and other anti-infective therapies.
- Existe relação entre a infeção por SARS-COV-2 e diabetes MELLITUS em Portugal?Publication . Correia, C.; Fernandes, Rúben; Baylina, Pilar; Faria, B.Em 2019 assistiu-se ao aparecimento da doença causada pelo SARS-CoV-2 que é conhecida como COVID-19, na China. A pandemia do COVID-19 foi declarada em 2020, pela OMS e ainda hoje assola todo o mundo. A COVID-19 é altamente infeciosa e a maioria dos pacientes tem mais de 50 anos, sendo que estes apresentam pelo menos uma comorbilidade associada, entre as quais a Diabetes mellitus (Dm). A Dm é uma doença metabólica em que se verificam níveis elevados de glicose no sangue, durante um longo período. Neste trabalho pretende realizar um estudo bioestatístico da relação entre infeção por SARS-CoV-2 e Dm em Portugal. Neste estudo foram utilizados os dados estatísticos disponibilizados pela Direção Geral de Saúde, Ministério da Saúde, Instituto Nacional de Estatística e PORDATA, relativamente a 2020. O estudo bioestatístico e respetivas análises foram realizadas utilizando o software IBM SPSS Statistics. Os dados foram testados para verificar a sua normalidade usando teste de Shapiro-Wilk. Dado não se verificar a normalidade, calculou-se a correlação de Spearman. A correlação entre as variáveis foi investigada nas diferentes regiões. A correlação entre as variáveis total de casos e diabéticos, o valor p é de <0.001 o que indica que o coeficiente de correlação de 0.964 é estatisticamente significativo. O coeficiente de correlação positivo indica que quando a proporção de população com Diabetes aumenta, a proporção de população com COVID-19 também aumenta. Este estudo explorou a correlação entre COVID-19 e Dm e usando todos os dados disponíveis até 31 de dezembro de 2020, para Portugal. Os resultados deste trabalho mostram um coeficiente de correlação positivo bastante significativo entre as duas doenças (COVID-19 e Dm). Isto indica que se a prevalência de Dm aumenta, a prevalência de casos COVID-19 também aumenta.
- The role of MTHFR polymorphisms in breast cancer risk– A metaanalysisPublication . Costa, J.; Oliveira, S.; Oliveira, R.; Prudêncio, Cristina; Fernandes, RúbenBreast cancer incidence has been increasing by more than one million new cases every year and is a primary cause of cancer death among women worldwide. Methylenetetrahydrofolate reductase (MTHFR) plays an important role in folate metabolism and as a regulator of DNA methylation, synthesis, and repair. MTHFR gene is polymorphic at nucleotides 677 (C®T) and 1298 (A®C), resulting in allozymes with decreased activity. Several studies have pointed to association between the MTHFR C677T polymorphism and breast cancer risk.
- The synergic effect of antibiotics is dependent of oxidative stress genes in Pseudomonas aeruginosaPublication . Fernandes, Rúben; Coelho, Pedro Barata; Guedes, Carla; Gojon, Frantz; Oliveira, Marco; Veiga, Marlene; Sá, Sara; Silva, Carina; Baylina, PilarPseudomonas aeruginosa is a Gram-negative opportunistic pathogen commonly found in Cystic fibrosis, infected wound of the diabetic foot among others. Clinical management of such infection depends deeply on the antibiotic therapy. Antibiotic response is dependent, among several other factors, to the response to host stress conditions, such as low-grade inflammation, metabolic conditions and oxidative stress and to social bacteria response such as quorum sensing and biofilm formation. P. aeruginosa, in particular strain PAO1 is also a biological model for studying bacterial biofilm formation. The present study aims to understand the antibiotic synergic response (ampicillin, ceftazidime, ciprofloxacin) in biofilm formation / degradation of 10 PAO1 oxidative gene mutants. Viability was measured by means of Erythrosin B and biofilm formation was measured by Crystal Violet assay. PAO1 GRLX, SEPHS 1, Rub A1, where the strains with a most pronounced biofilm formation and combination of ceftazidme::ciprofloxacin were most efficient in this biological model. The results are interesting, and although they are encouraging, they should be taken with caution.
- Oxidative stress genes involved in the virulence-dependent susceptibility to antibiotics in Pseudomonas aeruginosaPublication . Coelho, Pedro Barata; Fernandes, Ruben; Silva, Carina; Oliveira, Marco; Veiga, Marlene; Sá, Sara; Vieira, André; Guedes, Carla; Baylina, PilarPseudomonas aeruginosa is a Gram-negative opportunistic pathogen which rarely causes disease in healthy people. P. aeruginosa, in particular strain PAO1 is also a biological model for studying virulence and bacterial social traits, such as quorum sensing, SOS response among other. Antibiotic response is dependent, among several other factors, to the response to environmental stress conditions. The present study aims to understand the role of 10 PAO1 oxidative gene mutants in the response to antibiotic stress in elastase, protease and pyocyanin-dependent virulence factors. PAO1 was stressed to several antibiotics (penicilins, cephalosporins, macrolides, and quinolones), and the virulence proteins were measured by means of spectroscopic methods. Viability was measured by means of Erythrosin B. PAO1 GGT, GLO1, RubA2, GSH A mutants were the most susceptible to the production of virulence-dependent factors.
- Phylogenetic Insights of β-lactam resistance of the CTX-M familyPublication . Coelho, Pedro Barata; Mendonça, Jacinta; Silva, Carina; Baylina, Pilar; Fernandes, Ruben; Guedes, CarlaBacterial resistance is a major public health concern, particularly against β-lactam antibiotics, one of the most widely used antibacterial drugs. The production of extended-spectrum β-lactamases (ESBLs) is the main defense mechanism found in Gram negative bacteria. Among all the ESBLs, the CTX-M enzymes appear as the most efficient in terms of diffusion in different epidemiological contexts, outnumbering the others. Originated in chromosomal genes of Klyvera spp., the blaCTX-M genes have become associated with mobile genetic elements, such as plasmids, that have mediated inter-replication and dissemination. CTX-M enzymes exhibit a striking plasticity, with a large number of allelic variants belonging to several sub-lineages, which can be associated with functional heterogeneity of clinical relevance. This observational analytical study provides an update of this family, currently with more than 200 variants described, from a phylogenetic, molecular and structural point of view through homology in amino acid sequences. There are currently 6 defined clusters (CTX-M-1, CTX-M-2, CTX-M-8, CTX-M-9, CTX-M-25 and CTX-M-151), with the domains CTX -M-1 and CTX-M-9 presenting subgroups, composed mainly of variants identified as hybrids between them (particularly between CTX-M-14 and CTX-M-15).
- 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).