The objective of this study was to investigate the osteogenic and antimicrobial effect of bioactive glass S53P4 incorporated into β-tricalcium phosphate (β-TCP) scaffolds in vitro and the bone neoformation in vivo. β-TCP and β-TCP/S53P4 scaffolds were prepared by the gel casting method. Samples were morphologically and physically characterized through X-ray diffraction (XRD) and scanning electron microscope (SEM). In vitro tests were performed using MG63 cells. American Type Culture Collection reference strains were used to determine the scaffold's antimicrobial potential. Defects were created in the tibia of New Zealand rabbits and filled with experimental scaffolds. The incorporation of S53P4 bioglass promotes significant changes in the crystalline phases formed and in the morphology of the surface of the scaffolds. The β-TCP/S53P4 scaffolds did not demonstrate an in vitro cytotoxic effect, presented similar alkaline phosphatase activity, and induced a significantly higher protein amount when compared to β-TCP. The expression of Itg β1 in the β-TCP scaffold was higher than in the β-TCP/S53P4, and there was higher expression of Col-1 in the β-TCP/S53P4 group. Higher bone formation and antimicrobial activity were observed in the β-TCP/S53P4 group. The results confirm the osteogenic capacity of β-TCP ceramics and suggest that, after bioactive glass S53P4 incorporation, it can prevent microbial infections, demonstrating to be an excellent biomaterial for application in bone tissue engineering.
Introducao: Os fungos tem apresentado um aumento nas taxas de infeccoes invasivas. As infeccoes fungicas estao relacionadas a 49% dos casos de mortalidade por infeccoes nasocomiais, principalmente nos casos de septicemia. As principais infeccoes fungicas sao causadas por patogenos oportunistas, umas vez que estes se aproveitam das condicoes imunitarias do hospedeiro para desenvolver uma doenca. Alem disso, apresentam grande resistencia aos farmacos disponiveis atualmente. Devido ao aumento de resistencia aos farmacos, que os microrganismos estao adquirindo, sao necessarios novos mecanismos de combate aos patogenos. Neste contexto, extratos naturais podem conter diversas funcoes biologicas, porem poucos possuem suas propriedades verificadas. Objetivo: Avaliar a acao antifungica dos extratos glicolicos de Pfaffia paniculata e Juglans regia nas cepas de Candida guilhermondii, Candida krusei e Candida tropicalis e a citotoxicidade sobre Fibroblastos gengivais humanos (FMM-1). Metodologia: Foi realizado o teste de Microdiluicao em caldo segundo Clinical and Laboratory Standards Institute (CLSI), utilizando o protocolo M27-A3. Apos obter os valores de CMM (concentracao microbicida minima) foram carreados os testes em biofilmes. Os biofilmes foram formados em placas de 96 pocos por 48h e foram tratados por 5 min com os extratos nas concentracoes de 200, 100 e 50 mg/ml. O grupo controle recebeu tratamento com solucao salina (NaCl 0,9%). A mensuracao foi feita atraves dos testes de MTT e cristal violeta. A citotoxicidade sobre FMM-1 foi avaliada seguindo os mesmos parâmetros. Os dados obtiveram distribuicao normal e foram analisados por Anova complementado pelo teste de Tukey (p<0.05%). Resultados e discussao: C. tropicalis obteve CMM com 50 mg/ml do extrato de P. paniculta, ja a C. krusei e C. guilhermondii obtiveram com 100 mg/ml. O extrato de J. regia promoveu CMM com 25 mg/ml do extrato, para todas as cepas. A biomassa de C. krusei, C. tropicalis e C. guilhermondii obtiveram reducoes de 37.5, 34.3 e 40.0% apos 200 mg do extrato de P. paniculata. As reducoes para J. regia (200 mg/ml) foram de20.4, 30.4 e 27.0%sobre C. krusei, C. tropicalis e C. guilhermondii. A atividade metabolica de C. krusei foi reduzida em 16.9% com 200 mg do extrato de P. paniculata. Para C. tropicalis e C. guilhermondii as reducoes foram de 61.6 e 14.5%. O extrato de J. regia promoveu reducoes na viabilidade de 20.5, 44.9 e 18.0%, para C. krusei, C. tropicalis e C. guilhermondii respectivamente. Os biofilmes de C. krusei obtiveram maior reducao na biomassa apos aplicacao do extrato, ja C. tropicalis e C. guilhermondi apresentaram maior reducao na atividade metabolica. O extrato de P. paniculata (200mg/ml) promoveu a reducao de 49.4% dos fibroblastos e J. regia (200mg) reduziu 14.9%. Conclusao: Os extratos promoveram importante acao antifungica sobre Candida spp e nao apresentaram citotoxicidade na linhagem FMM-1.
Objective: Evaluate the anti-biofilm activity of Gymnema sylvestre, Hamamelis virginiana, Juglans regia, Persea americana, Pfaffia paniculata, Rosmarinus officinalis, Stryphnodendron barbatiman and Thymus vulgaris extracts in 3 MDR strains and 1 ATCC (4352) of Klebsiella pneumoniae. Methods: First were made a screening with broth microdilution test, protocol M7-A9, according to CLSI. Extracts that presented values for Minimal Microbicidal Concentration (MMC) were selected for biofilms tests on 96 wells plates. Treatments used concentrations of 25 and 50 mg/mL, after biofilms were measured by biomass and MTT tests and statistically analyzed by ANOVA and Tukey test (p<0.05). Results: All extracts showed MIC for all K. pneumoniae strains studied, with values ranging from 12.5-100 mg/mL. Biomass of the strains ATCC and MDR strain (400381) of K. pneumoniae obtained reductions of 37.7 and 44.3% with P. paniculata and R. officinalis extracts. The isolate 386546 obtained a reduction of 29.7% (p<0.05) under R. officinalis action. Conclusion: Among the extracts studied, those that were most effective in the anti-biofilm action were J. regia, P. paniculata and R. officinalis. Therefore, these extracts could act as bactericidal agents against K. pneumoniae MDR.