Browsing by Author "Duarte, Ana Sofia"
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- #064 Caracterização biológica dos derivados do osso de choco para aplicação em endodontiaPublication . Fortuna, Teresa; Pinheiro, Suelen; Peixoto, Ana; Ferreira, José Maria; Noites, Rita; Duarte, Ana SofiaObjetivos: Avaliar as propriedades antimicrobianas e citotóxicas do osso de choco de forma a selecionar o material de medicação intra-canalar com maior potencial de aplicação em endodontia. Materiais e métodos: A citotoxicidade de osso de choco hidrotermalmente processado foi estudada numa linha celular proveniente de rim de macaco (células VERO) de acordo com a Norma ISO 10993? 5. A viabilidade celular das células VERO após incubação com o osso de choco foi avaliada através do método colorimétrico da redução da Resazurina. Foram testadas diferentes concentrações de pó de osso de choco (6,5, 25, 100 e 400 μg/ml) e todos os resultados foram comparados com hidróxido de cálcio. Para o estudo da capacidade de inibição do crescimento de Candida albicans promovido pelo osso de choco foi utilizado o método da sementeira por gota. Resultados: Os resultados da citotoxicidade mostram que o pó de osso de choco não promove uma redução significativa da viabilidade das células VERO, mostrando que este material não é citotóxico. Mesmo não sendo considerado citotóxico para as células VERO, o hidróxido de cálcio induziu maior toxicidade para esta linha celular, quando comparado com o osso de choco, particularmente nas concentrações 25 μg/mL e 100 μg/mL (p<0,001). Os ensaios da atividade antimicrobiana permitiram verificar uma redução do número de colónias de C. albicans na presença de 100 μg/mL de osso de choco, quando comparado com o controlo, mostrando que o osso de choco inibe o crescimento deste fungo. Conclusões: O pó de osso de choco processado hidrotermalmente não apresenta citotoxicidade para as células VERO, em todas as concentrações testadas, tendo promovido a inibição do crescimento de C. albicans. A aplicação deste tipo de material é promissora na área da endodontia, não só como medicação intra-canalar, mas também noutro tipo de aplicações como na apexificação, perfurações infra-ósseas, revascularização ou proteções pulpares.
- Antimicrobial properties and bioactivity potential of smart nanoparticles for dental applicationsPublication . Correia, Bruna L.; Malekshiri, Moslem; Bartolomeu, Maria; Silva, Virgília; Oliveira, Ana; Noites, Rita; Cardoso, Miguel; Mendes, Karina; Gomes, Ana T. P. C.; Duarte, Ana Sofia
- Degree of contamination of gutta-percha points by Staphylococcus aureus (MRSA/MSSA) strainsPublication . Teles, Ana Moura; Pina, Cristina; Cardoso, Inês Lopes; Tramontana, Antea; Cardoso, Miguel; Duarte, Ana Sofia; Bartolomeu, Maria; Noites, RitaMethicillin-resistant Staphylococcus aureus (MRSA) is considered one of the most harmful bacteria to human health. Dentistry, like all healthcare disciplines, places great emphasis on preventing scenarios that may result in cross-infection. Although various tested and already used materials are suitable for filling the root canal system, Gutta-Percha (GP) remains the preferred and widely accepted gold standard. Objective: We performed an in vitro analysis of the contamination of GP points, regarding the strains of Methicillin-resistant (MRSA) and Methicillin-sensitive (MSSA) Staphylococcus aureus, using classical microbiology methods and molecular biology techniques. Methods: Gutta-Percha points of two different brands from opened packages (already in use for 1 month) were collected for analysis. The assessment involved incubating the GP points in Brain Heart Infusion (BHI) medium to detect microbial growth. Growing microorganisms were plated on a selective and differential chromogenic medium for MRSA/MSSA strains, and the identification of isolates was confirmed by Polymerase Chain Reaction (PCR). In the case of microbial growth, the GP point was submitted to a disinfection protocol. Results: From the 315 collected GP points, only 6 (1.9%) resulted in being positive for microbial growth. After confirmation by PCR, only one sample of the six GP points was contaminated by MRSA, and the remaining five were MSSA-contaminated. The disinfection protocol was effective in all contaminated GP points. Conclusions: The Gutta-Percha points from opened pre-sterilized packages showed a very low degree of contamination by MRSA/MSSA. However, the detection of MSSA and MRSA strains raises concerns about potential contamination in dental clinic environments, and this risk cannot be considered negligible.
- Dique de borracha na diminuição de microrganismos nos aerossóisPublication . Cardoso, Miguel Agostinho; Milheiro, André; Cruz, Bárbara; Noites, Rita; Duarte, Ana SofiaObjetivos: Avaliar se o dique de borracha interfere na disseminação de microrganismos em aerossóis gerados durante o uso de instrumentos rotatórios no tratamento de cáries. Materiais e métodos: Foram realizados 20 tratamentos de cárie, sendo dez com dique de borracha (DB) e dez sem dique de borracha (SDB). Foram utilizados três pontos de recolha: operador (DB n=10; SDB n=10), assistente (DB n=10; SDB n=10) e bandeja (DB n=10; SDB n=10). Em cada local foram aplicadas duas placas de Petri: (Ágar Trypticase Soy fluconazol) para selecionar bactérias e (Ágar Sabouraud Dextrose ampicilina) para selecionar fungos. Houve um tempo de exposição de 15 min durante o uso dos instrumentos rotatórios. As placas foram incubadas durante 24h e as unidades formadoras de colónias (UFC) foram contadas e comparadas usando estatísticas de sobrevivência (p<0,05). Na fase final do estudo, os isolados clínicos foram identificados por sequenciação parcial de nucleotídeos da subunidade ribossomal. Resultados: Uma maior contagem de UFC foi obtida nos grupos em que não foi utilizado dique de borracha em comparação àqueles em que foi aplicado dique de borracha (p=0,022). Embora não tenham sido observadas diferenças estatisticamente significativas entre os pontos de recolha no operador e no assistente, na bandeja, o grupo onde foi utilizado dique apresentou menor número de UFC em relação ao grupo sem dique (p=0,004). A sequenciação nucleotídica permitiu identificar Staphylococcus, Pseudomonas, Micrococcus e Bacillus. Conclusões: Este estudo experimental enfatiza a importância do uso do dique de borracha durante os procedimentos clínicos que utilizam instrumentos rotatórios, reduzindo o risco de contaminação por aerossóis, além de promover a segurança do paciente durante o tratamento.
- Editorial: innovative biocontrol strategies to manage crop and pest diseasesPublication . Fontaine, Florence; Duarte, Ana Sofia; Fischer, Jochen
- Effect of γ-aminobutyric acid (GABA) on the metabolome of two strains of Lasiodiplodia theobromae isolated from grapevinePublication . Salvatore, Maria Michela; Félix, Carna; Lima, Fernanda; Ferreira, Vanessa; Duarte, Ana Sofia; Salvatore, Francesco; Alves, Artur; Esteves, Ana Cristina; Andolfi, AnnaThe effect of γ-aminobutyric acid (GABA) on the metabolome of two strains of Lasiodiplodia theobromae isolated from grapevine that hold a different degree of virulence to the host plant (LA-SOL3 (more virulent), LA-SV1 (less virulent)) was investigated. The culture filtrates and crude extracts from the two strains grown in the presence and absence of 10 mM of GABA were tested for phytotoxicity on tomato plant cuttings and leaves, respectively. Considering the opportunistic nature of this fungus for humans, crude extracts were also tested for cytotoxicity on mammalian cell lines. We found that culture filtrates and crude extracts have a decreased toxicity in the presence of GABA. Metabolomic analysis, conducted on both strains at both growth conditions, revealed the production of several compounds, such as indole-3-carboxylic acid (ICA, which is the main compound produced by L. theobromae), 3-indolecarboxyaldehyde, (3R,4S)-botryodiplodin, (R)-mellein. Finally, data demonstrate that GABA both induces a decrease in the amount of ICA, and a diversification of the metabolites produced by L. theobromae.
- Factors associated with the prevalence of apical periodontitis: an observational studyPublication . Noites, Rita; Bartolomeu, Maria; Duarte, Ana Sofia; Perez, Alejandro; Cardoso, MiguelObjectives: Apical periodontitis is a lesion of endodontic origin caused by an immune response to necrotic and infected dental pulp. Since apical periodontitis can persist after endodontic treatment, radiographic diagnosis is crucial. This study evaluates factors associated with the prevalence of apical periodontitis in a Portuguese population using the full-scale periapical index. Methods: A cross-sectional study analyzed 402 medical records and panoramic radiographs from January to May 2023. The periapical status, presence of apical periodontitis, quality of endodontic treatment, quality of coronal restoration, presence of caries lesions, and presence of retained root fragments were assessed. The correlation between these variables was examined. Results: Among 9056 teeth, 4.7% presented apical periodontitis (periapical index ≥3), and 53.3% of participants had fewer than one apical periodontitis lesion. Of 437 teeth with endodontic treatment, 300 (69.6%) did not have apical periodontitis, while 131 (30.4%) had apical periodontitis. A significant statistical relationship (p<0.05) was observed between apical periodontitis and other dental conditions, including the presence of retained root fragments, caries lesions, the quality of endodontic treatment, and the quality of restoration. The strongest correlation was found between apical periodontitis and the quality of endodontic treatment (Cramer’s V = 61%), while no consistent correlations were observed with other variables. Conclusions: The prevalence of apical periodontitis was higher in teeth with endodontic treatment, with a strong correlation with treatment quality. The presence of caries lesions, coronal restorations, and retained root fragments also influenced the occurrence of apical periodontitis, reinforcing the need for further studies.
- Identification and characterization of Candida spp. from denture stomatitis patientsPublication . Carvalho, Gonçalo; Lourenço, Juliana; Abrantes, Ana; Fernandes, Mónica; Correia, Maria José; Duarte, Ana Sofia; Silva, Raquel M.
- Molecular techniques and target selection for the identification of Candida spp. in oral samplesPublication . Magalhães, Joana; Correia, Maria José; Silva, Raquel M.; Esteves, Ana Cristina; Alves, Artur; Duarte, Ana SofiaCandida species are the causative agent of oral candidiasis, with medical devices being platforms for yeast anchoring and tissue colonization. Identifying the infectious agent involved in candidiasis avoids an empirical prescription of antifungal drugs. The application of high-throughput technologies to the diagnosis of yeast pathogens has clear advantages in sensitivity, accuracy, and speed. Yet, conventional techniques for the identification of Candida isolates are still routine in clinical and research settings. Molecular approaches are the focus of intensive research, but conversion into clinic settings requires overcoming important challenges. Several molecular approaches can accurately identify Candida spp.: Polymerase Chain Reaction, Microarray, High-Resolution Melting Analysis, Multi-Locus Sequence Typing, Restriction Fragment Length Polymorphism, Loop-mediated Isothermal Amplification, Matrix Assisted Laser Desorption Ionization-mass spectrometry, and Next Generation Sequencing. This review examines the advantages and disadvantages of the current molecular methods used for Candida spp. Identification, with a special focus on oral candidiasis. Discussion regarding their application for the diagnosis of oral infections aims to identify the most rapid, affordable, accurate, and easy-to-perform molecular techniques to be used as a point-of-care testing method. Special emphasis is given to the difficulties that health care professionals need to overcome to provide an accurate diagnosis.
- O4 - Exploring the biological properties and regenerative potential of biomaterials using cell culture modelsPublication . Duarte, Ana Sofia; Correia, Bruna L.; Bartolomeu, Maria; Mendes, Karina; Gomes, Ana T. P. C.Life expectancy has improved signifcantly and, along with the declining birthrate, has contributed to the aging of populations, especially in industrialized countries. Alas, aging is intrinsically associated with the incidence of health problems including bone and tooth loss that require suitable solutions to support the quality of life. To meet these demands, signifcant research eforts have been undertaken to develop novel biomaterials, both orthopedic and dental implants. The feld of biomaterials for bone tissue engineering is increasingly evolving. The most recent generations of biomaterials have increasingly more activity and interaction with the biological environment and stimulate the regeneration of functional tissue. Natural polymers and compounds have been combined with each other to improve workability and are strategically integrated with ceramics or bioactive glasses to reinforce the structure of the fnal system, thus producing composites with a better mechanical performance. Our research group has been focused on the biological characterization of diferent added-value materials and composites, namely by evaluating their antimicrobial, biocompatibility, and regenerative properties. Some of our recent work results allowed us to conclude that marine fungal extracts, as well as sol–gel-derived bioactive glass nanoparticles, have inhibitory efects on the growth of C. albicans and E. faecalis (main pathogens in persistent root canal infections). Additionally, we have characterized cuttlefsh bone powders for endodontic applications. We are also committed to developing strategies for monitoring cell response to these biomaterials at the molecular level that could be used to follow infammation and osteoconduction.