Preparation and antimicrobial activity of gelatin microparticles containing propolis against oral pathogens

Gelatin microparticles containing propolis ethanolic extractive solution were prepared by spray-drying technique. Particle,, with regular morphology, mean diameter ranging of 2.27 mu m to 2.48 mu m, and good entrapment efficiency for propolis were obtained. The in vitro antimicrobial activity of microparticles was evaluated against microorganisms of oral importance (Enterococcus faecalis, Streptococcus salivarius, Streptococcus sanguinis, Streptococcus mitis, Streptococcus mutans, Streptococcus sobrinus, Candida albicans, and Lactobacillus casei). The utilized techniques were diffusion in agar and determination of minimum inhibitory concentration. The choice of the method to evaluate the antimicrobial activity of microparticles showed be very important. The microparticles displayed activity against all tested strains of similar way to the propolis, showing greater activity against the strains of E. salivarius, S. sanguinis, S. mitis, and C albicans.

Composition and Activity against Oral Pathogens of the Essential Oil of Melampodium divaricatum (Rich.) DC.

The chemical composition of the essential oil isolated from the aerial parts of Melampodium divaricatum (Rich.) DC. (Asteraceae) was characterized by GC-FID and GC/MS analyses. (E)-Caryophyllene (56.0%), germacrene D (12.7%), and bicyclogermacrene (9.2%) were identified as the major oil components. The antimicrobial activity of the oil against seven standard strains of oral pathogens from the American Type Culture Collection (ATCC) was evaluated by determining minimum inhibitory concentrations (MICs) using the microdilution method. MIC Values below 100 mu g/ml were obtained against Streptococcus sobrinus (90 mu g/ml), Lactobacillus casei (30 mu g/ml), S. mutans (20 mu g/ml), and S. mitis (18 mu g/ml). In contrast, the MIC values of the major oil compound (E)-caryophyllene were higher than 400 mu g/ml against all pathogens, suggesting that the activity of the oil might depend on minor oil components and/or on synergistic effects. The M. divaricatum essential oil is a promising agent to include in anticariogenic oral rinse formulations for the control of oral pathogens.

The Potential of p38 MAPK Inhibitors to Modulate Periodontal Infections

Periodontal disease initiation and progression occurs as a consequence of the host immune inflammatory response to oral pathogens. The innate and acquired immune systems are critical for the proper immune response. LPS, an outer membrane constituent of periodontal pathogenic bacteria, stimulates the production of inflammatory cytokines IL-1 beta TNF alpha IL-6 and RANKL either directly or indirectly. In LPS-stimulated cells, the induction of cytokine expression requires activation of several signaling pathways including the p38 MAPK pathway. This review will discuss the significance of the p38 MAPK pathway in periodontal disease progression and the potential therapeutic consequences of pharmacological antagonism of this pathway in the treatment of periodontal diseases.

Avaliação da microbiota bucal de mães e pares de crianças aos 6, 12, 18 e 24 meses de idade e sua relação com dieta alimentar, hábitos de higiene bucal, condição gengival, erupção dentária e prevalência de cárie dentária

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Antimicrobial activity of Uncaria tomentosa against oral human pathogens

Uncaria tomentosa is considered a medicinal plant used over centuries by the peruvian population as an alternative treatment for several diseases. Many microorganisms usually inhabit the human oral cavity and under certain conditions can become etiologic agents of diseases. The aim of the present study was to evaluate the antimicrobial activity of different concentrations of Uncaria tomentosa on different strains of microorganisms isolated from the human oral cavity. Micropulverized Uncaria tomentosa was tested in vitro to determine the minimum inhibitory concentration (MIC) on selected microbial strains. The tested strains were oral clinical isolates of Streptococcus mutans, Staphylococcus spp., Candida albicans, Enterobacteriaceae and Pseudomonas aeruginosa. The tested concentrations of Uncaria tomentosa ranged from 0.25-5% in Müeller-Hinton agat. Three percent Uncaria tomentosa inhibited 8% of Enterobacteriaceae isolates, 52% of S. mutans and 96% of Staphylococcus spp. The tested concentrations did not present inhibitory effect on P. aeruginosa and C. albicans. It could be concluded that micropulverized Uncaria tomentosa presented antimicrobial activity on Enterobacteriaceae, S. mutans and Staphylococcus spp. isolates.

Proteins, Pathogens, and Failure at the Composite-Tooth Interface

In the United States, composites accounted for nearly 70% of the 173.2 million composite and amalgam restorations placed in 2006 (Kingman et al., 2012), and it is likely that the use of composite will continue to increase as dentists phase out dental amalgam. This trend is not, however, without consequences. The failure rate of composite restorations is double that of amalgam (Ferracane, 2013). Composite restorations accumulate more biofilm, experience more secondary decay, and require more frequent replacement. In vivo biodegradation of the adhesive bond at the composite-tooth interface is a major contributor to the cascade of events leading to restoration failure. Binding by proteins, particularly gp340, from the salivary pellicle leads to biofilm attachment, which accelerates degradation of the interfacial bond and demineralization of the tooth by recruiting the pioneer bacterium Streptococcus mutans to the surface. Bacterial production of lactic acid lowers the pH of the oral microenvironment, erodes hydroxyapatite in enamel and dentin, and promotes hydrolysis of the adhesive. Secreted esterases further hydrolyze the adhesive polymer, exposing the soft underlying collagenous dentinal matrix and allowing further infiltration by the pathogenic biofilm. Manifold approaches are being pursued to increase the longevity of composite dental restorations based on the major contributing factors responsible for degradation. The key material and biological components and the interactions involved in the destructive processes, including recent advances in understanding the structural and molecular basis of biofilm recruitment, are described in this review. Innovative strategies to mitigate these pathogenic effects and slow deterioration are discussed.

Periodontal pathogens directly promote autoimmune experimental arthritis by inducing a TLR2- and IL-1-Driven Th17 response

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Occurrence of periodontal pathogens in ethnic groups from a native Brazilian reservation

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)