159 resultados para biological properties
Resumo:
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Resumo:
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Resumo:
Pós-graduação em Patologia - FMB
Resumo:
Pós-graduação em Odontologia - FOAR
Resumo:
Pós-graduação em Odontologia - FOAR
Resumo:
Natural products have been studied aiming to understand their biological properties. Thus, this study aimed to investigate the antimicrobial activity of twenty-seven essential oils (EOs) used in aromatherapy procedures, a natural therapy with great emphasis currently used against Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa strains. The agar dilution method was carried out and minimal inhibitory concentration against 50% and 90% of strains (MIC50% and MIC90% values) were reported. The S.aureus strains were highly susceptible with MIC90% from 0.21mg/mL to black pepper (Piper nigrum) and tea tree (Melaleuca alternifolia) to 26.52mg/mL with copaiba (Copaifera officinalis) EO. Cinnamon (Cinnamomum cassia) and clove (Syzygium aromaticum) EOs were effective against E.coli (2.0mg/mL) while the S.aromaticum EO was against P.aeruginosa (8.29mg/mL). Thus, the higher susceptibility of Gram-positive bacteria when compared with Gram-negative strains was found, and a large variability in the potential antibacterial has also been observed.
Resumo:
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Resumo:
Combining the characteristics of good adhesion and sealing of the AH Plus sealer the biological properties of the MTA, zinc oxide and calcium hydroxide, the purpose of this study was to evaluate the cytotoxicity of these associations. The specimens of the sealers and their associations were mixed and exposure to culture medium (82.4 mm2surface/mL) after the manipulation and incubated in a humidified incubator (37°C and 100% humidity) for 24 h. Chinese hamster lung fibroblasts (V79) were exposed to different dilutions of this extracts for 24 h and cell viability was measured by MTT test. The differences between the cell survival rates were statistically analyzed for Kruskal-Wallis and Dunn (p≤0.05). All sealers showed a significant difference with the group control, except the MTA. Cytotoxicity with the control group increased in the following order: AH Plus < AH Plus + Ca(OH) 2 < AH Plus + OxZn< AH Plus + MTA < MTA (p≤ 0,05). It was concluded that the addition of biological materials in order to improve the consistency of AH Plus for use in retro cavities its toxicity has not decreased significantly
Resumo:
Kaposi´s sarcoma associated herpesvirus (KSHV) or human herpesvirus 8 (HHV-8) is a gammaherpesvirus essential for the development of all forms of Kaposi´s sarcoma (KS). The KSHV’s life cycle is basically divided into latent and lytic phases, which have distinct viral gene expression profiles. Some important oncogenic products of KSHV are expressed during the lytic phase, including the viral K1 protein. As an effect of interfer-ence with intracellular signaling, K1 expression increases proliferation and survival of KSHV-infected cells. Due to its high level of genetic variability compared to other re-gions of the viral genome, the K1-encoding ORF (ORF-K1) is commonly evaluated for KSHV genotyping. It remains unclear whether different viral genotypes have particular biological effects that might modify the KSHV oncogenicity. The present study aimed to contribute to the establishment of an experimental in vitro model for evaluation of the K1 protein from common KSHV genotypes. Recombinant expression vectors with the ORF-K1 from KSHV genotypes A, B and C were prepared by genetic cloning. The recombi-nant vectors pKSHVOK1 obtained by cloning were sequenced for structural validation. After that, HEK293 cell line was transfected with the recombinant vectors, and proteins were extracted for expression analysis by Western blot technique, for K1 functional vali-dation. Results showed that ORF-K1 vectors containing KSHV ORF-K1 from the A, B and C genotypes were produced and structurally validated by DNA sequencing. The K1 expression at the protein level was also confirmed by immunoblots using an antibody for FLAG detection, an epitope from the vector that binds to K1. Based on presented re-sults, it´s possible to conclude that the recombinant vectors will be able to be used in future studies of K1 protein biological properties from distinct KSHV genotypes
Resumo:
Pós-graduação em Ciência dos Materiais - FEIS
Resumo:
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Resumo:
Unilateral or bilateral distal-extension removable partial dentures present complex biomechanics. The movements in different directions, associated with the alveolar ridge shape and soft tissue resilience can lead to damaging forces on the supporting structures. The association between implants / removable partial denture aims to provide better mechanical and biological properties to the stomatognathic system. OBJECTIVE: The aim of this paper was to review the articles about the effect of implant support on distal extension removable partial dentures. LITERATURE REVIEW AND CONCLUSION: Studies have shown that this combination provides greater support, retention and stability to the prosthesis, thus limiting their approach movement toward supporting tissues and providing functional and psychological comfort to patients.
Resumo:
Introduction: Unilateral or bilateral distal-extension removable partial dentures present complex biomechanics. The movements in different directions, associated with the alveolar ridge shape and soft tissue resilience can lead to damaging forces on the supporting structures. The association between implants / removable partial denture aims to provide better mechanical and biological properties to the stomatognathic system. Objective: The aim of this paper was to review the articles about the effect of implant support on distal extension removable partial dentures. Literature review and conclusion: Studies have shown that this combination provides greater support, retention and stability to the prosthesis, thus limiting their approach movement toward supporting tissues and providing functional and psychological comfort to patients.
Resumo:
The Portland cement has shown similar biological properties to calcium hydroxide, but its radiopacity is lower. Therefore, the addition of materials that minimize this deficiency should be considered. OBJECTIVE: To evaluate the apical sealing ability and pH of a white Portland cement added of several radiopacifying agents. MATERIAL AND METHODS: Forty bovine roots with incomplete apices were selected, and the foraminal openings were standardized to PM 720G bur. After the external root sealing, an apical intracanal barrier 10.0 mm thick was executed with the white Portland cement powder, pure or added of a radiopacifying agent (iodoform, zinc oxide or bismuth subnitrate), and distilled water (0.37 mL). The apical roots were immersed 24h in water in humid atmosphere, and after that they were immersed 24h in 2% Rhodamine B, under vacuum. In sequence, the roots were longitudinally sectioned, the root fragments were photographed, the images were digitalized and the apical infiltration was measured by the Image Tool program. The pH solutions were also evaluated, in 24h and 48h and 7 and 30 days. Data were submitted to Anova test. RESULTS: The zinc oxide solution has the lowest apical infiltration in relation to the other groups (p < 0.05). The pH behavior varied during the analysis, and in the period of 24h all groups showed the highest values (p < 0.05). CONCLUSION: The type of radiopacifying agent used interferes in the sealing ability of the apical barrier, and zinc oxide showed to be the most beneficial one. The pH varies according to the period of analysis, and the highest values were obtained in the first 24h (p < 0.05).
Resumo:
MTA is composed of various metal oxides, calcium oxide and bismuth. It has good biological properties and is indicated in cases of endodontic complications. Several commercial formulations are available and further studies are necessary to evaluate these materials. Objective: To evaluate pH and calcium releasing of MTA Fillapex® compared with gray and white MTA. Material and methods: Gray and white MTA (Angelus) and MTA Fillapex® (Angelus) were manipulated and placed into polyethylene tubes and immersed in distilled water. The pH of these solutions was measured at 24 hours, 7 days and 14 days. Simultaneously, at these same aforementioned periods, these materials' calcium releasing was quantified, through atomic absorption spectrophotometry. The results were submitted to ANOVA, with level of significance at 5%. Results: Concerning to pH, the materials present similar behaviors among each other at 24 hours (p > 0.05). At 7 and 14 days, MTA Fillapex® provided significantly lower pH values than the other materials (p < 0.05). Regarding to calcium releasing, at 24 hours and 7 days, MTA Fillapex® provided lower releasing than the other materials (p < 0.05). After 14 days, differences were found between MTA Fillapex® and gray MTA (p < 0.05). Conclusion: All materials showed alkaline pH and calcium releasing, with significantly lower values for MTA Fillapex® sealer.