Browsing by Author "Sousa, Ana Catarina"
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- Assessing exposure to environmental contaminants in portuguese mother-infant pairs: the project ARTEMISPublication . Namorado, Sónia; Pastorinho, M. Ramiro; Simões, Mariana; Coelho, Susana; Lamy, Elsa; Silva, Susana Pereira; Ogura, Joana; Nunes, Baltazar; Sousa, Ana CatarinaObjective: Today chemicals play a major role in our daily lives, being present in the air we breathe, in the food we eat and in the products we use. As such, it is essential to know the levels of chemicals present in our bodies and assess the risks associated. For that, Human Biomonitoring (HBM), the measurement of the concentrations of chemicals in human biological samples, is a very useful technique. Nevertheless, Portuguese HBM data is scarce and more knowledge on the exposure to chemicals of the Portuguese population is needed. It is then proposed to develop a study to assess the current environmental exposure of Portuguese children and women of childbearing age, vulnerable groups of the population, to selected chemicals, particularly metals and endocrine disruptors. Methods: The project ARTEMIS will evaluate exposure of children aged 6-11 years old and their mothers aged 45 years or less residing in four selected rural and urban areas in Portugal (LVT and Alentejo regions). Recruitment will be done through schools. Urine and hair samples will be collected for the analysis of exposure biomarkers, namely of metals (including mercury, cadmium and arsenic), bisphenols and cotinine. Additionally, saliva samples will be collected for the analysis of effect biomarkers (salivary proteome). Questionnaire data on socio-demographic characteristics, lifestyle, nutrition, health, and specific information on exposure to the selected chemicals will be collected using CATI (Computer-Assisted Telephone Interviewing). A biobank will also be established to allow further analysis of the samples. Expected results: ARTEMIS will be an innovative project that will not only produce much needed data on the current exposure of the Portuguese population to chemicals, but also allow to evaluate time trends of exposure to some chemicals by comparison with the results from previous projects and to study the association of exposure with biomarkers of effect.
- Chemical characterization and bioactive potential of Thymus × citriodorus (Pers.) Schreb. preparations for anti-acne applications: Antimicrobial, anti-biofilm, anti-inflammatory and safety profilesPublication . Oliveira, Ana S.; Rolo, Joana; Gaspar, Carlos; Cavaleiro, Carlos; Salgueiro, Lígia; Palmeira-de-Oliveira, Rita; Ferraz, Celso; Coelho, Susana; Pastorinho, M. Ramiro; Sousa, Ana Catarina; Teixeira, João Paulo; Martinez-de-Oliveira, José; Palmeira-de-Oliveira, AnaEthnopharmacological relevance: Thymus × citriodorus (Pers.) Schreb. is an interspecific hybrid between Thymus pulegioides and Thymus vulgaris, known for its pharmacological activities as diaphoretic, deodorant, antiseptic and disinfectant, the last mostly related with its antimicrobial activity. The folk use of other extracts, as hydrolates, have also been disseminated, as regulators of oily skin with anti-acne effect. Aim of the study: We aimed to evaluate the anti-acne potential of two Thymus x citriodorus (TC) preparations, the essential oil (EO) and the hydrolate, to be used as active ingredients for skin applications. Specifically, we intend to validate their anti-acne potential by describing their activity on acne related bacteria, bacterial virulence, anti-oxidant and anti-inflammatory potential, and biocompatibility on inflammatory cells. Additionally, we aimed to report their ecotoxicity under the Globally Harmonized System of Classification and Labelling of Chemicals (GHS), thus focusing not only on the consumer, but also on environmental safety assessment. Materials and methods: Minimum inhibitory concentration (MIC) against C. acnes, S. aureus and S. epidermidis was evaluated. Minimum lethal concentration (MLC) was also determined. The effect on C. acnes biofilm formation and disruption was evaluated with crystal violet staining. Anti-inflammatory activity was investigated on LPS-stimulated mouse macrophages (RAW 264.7), by studying nitric oxide (NO) production (Griess reagent) and cellular biocompatibility through MTT assay. In-vitro NO and 2,2-Diphenyl-1-picrylhydrazyl (DPPH) scavenging potential were also evaluated. The ecotoxicity was evaluated using Daphnia magna acute toxicity assays. Results: EO presented direct antimicrobial activity, with visual MICs ranging from 0.06% for S. epidermidis and C. acnes to 0.125% for S. aureus. MLCs were higher than the obtained MICs. Hydrolate revealed visual MIC only for C. acnes. TC essential oil was effective in preventing biofilm formation and disrupting preformed biofilms even at sub-inhibitory concentrations. Hydrolate showed a more modest anti-biofilm effect. Regarding anti-inflammatory activity, TC hydrolate has a higher cellular biocompatibility. Still, both plant preparations were able to inhibit at least 50% of NO production at non-cytotoxic concentrations. Both EO and hydrolate have poor anti-oxidant activities. Regarding the ecotoxicity, TC essential oil was classified under acute 3 category, while the hydrolate has proved to be nontoxic, in accordance to the GHS. Conclusions: These results support the anti-acne value of different TC preparations for different applications. TC hydrolate by presenting higher biocompatibility, anti-inflammatory potential and the ability to modulate C. acnes virulence, can be advantageous in a product for everyday application. On the other hand, EO by presenting a marked antimicrobial, anti-biofilm and anti-inflammatory activities, still with some cytotoxicity, may be better suited for application in acute flare-ups, for short treatment periods.
- Endocrine disrupting chemicals in indoor dust and the implications for human exposure: preliminary findingsPublication . Madureira, Joana; Sousa, Ana Catarina; Silva, Ana Inês; Aguiar, Lívia; Tanoue, Rumi; Kunisue, Tatsuya; Tanabe, Shinsuke; Teixeira, João Paulo; Costa, CarlaPersonal care products, including cosmetics and pharmaceuticals, are major sources of endocrine disrupting chemicals (EDC), such as parabens and triclosan (TCS) (Mitro et al. 2016). The use of these compounds has resulted in extensive environmental occurrence and human exposure. So far, levels of these chemicals in residences has not yet been fully explored, particularly in indoor dust (Chen et al. 2018; Geens et al. 2009). The objectives of the study were to determine the concentrations of four parabens and TCS in house dust samples and to estimate human exposure doses to these compounds through ingestion in different life stages (infants, toddlers, children, teenagers and adults).
- Frailty syndrome, biomarkers and environmental factors – A pilot studyPublication . Teixeira-Gomes, Armanda; Lage, Bruna; Esteves, Filipa; Sousa, Ana Catarina; Pastorinho, M. Ramiro; Valdiglesias, Vanessa; Costa, Solange; Laffon, Blanca; Teixeira, João PauloFrailty is an age-related syndrome expected to increase over the next decades. This syndrome has been identified to be the most common condition leading to disability, institutionalisation and death in the elderly. The aim of this pilot study is to investigate a possible link between frailty status, biomarkers and environmental exposures. A group of 71 older adults (≥65 years old) was engaged in this study. The study population was classified as 45.1% robust, 45.1% pre-frail and 9.8% frail. A significant higher prevalence of second-hand smokers was found in the pre-frail group when compared to robust. Furthermore, a higher prevalence of robust individuals was found among those consuming home-produced vegetables and water from well/springs. Significant differences were found between data collected in a lifetime exposure questionnaire (LTEQ) and the levels of genotoxicity endpoints and the mercury levels analysed regarding some exposure-related parameters, namely, smoking habits, intake of home-produced vegetables and the use of pesticides in agriculture. Understanding if the way we live(d) or worked can impact the way we age are important questions to be explored. Data obtained in this pilot study encourage further studies on this matter, exploring the role of exposures history and its impact on health.