Bacterial leakage in root canals filled with conventional and MTA-based sealers

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

In vitro antibacterial action of Tetraclean, MTAD and five experimental irrigation solutions

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

TNF-alpha activates human monocytes for Paracoccidioides brasiliensis killing by an H2O2-dependent mechanism

Human monocytes activated by recombinant tumor necrosis factor alpha (TNF-alpha) exhibited significant fungicidal activity on the yeast cells of a highly virulent strain of Paracoccidioides brasiliensis. This process was significantly inhibited in the presence of catalase (CAT - a scavenger of H2O2), but not in the presence of superoxide-dismutase (SOD - a scavenger of superoxide anion) or N-G-monomethyl-L- arginine (N-G-MMLA - a nitric oxide inhibitor). Furthermore, there was a direct association between the intracellular killing of the fungus and the production of H2O2 by activated cells. These results strongly suggest a role for H2O2 in the killing of highly virulent strains of P. brasiliensis by TNF-alpha-activated human monocytes.

Effect of interleukin-10 on the Paracoccidioides brasiliensis killing by gamma-interferon activated human neutrophils

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

Bacterial biofilms with emphasis on coagulase-negative staphylococci

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

Interleukin-15 increases Paracoccidioides brasiliensis killing by human neutrophils

Interleukin-15 is a cytokine produced by a wide range of different cell types, including macrophages, in response to lipopolysaccharide or microbial infection. This cytokine may play a crucial role in the activation of phagocytic cells against pathogens, especially during innate immune response. The effects of IL-15 on human polymorphonuclear leukocyte fungicidal activity against a highly virulent Paracoccidioides brasiliensis strain were investigated. Pretreatment of human neutrophils from healthy individuals with IL-15 for IS h increased cell fungicidal activity in a dose-dependent manner. In addition, the exposure to IL-15 induced an increase in neutrophil oxidative burst as evaluated by superoxide anion and H(2)O(2) release. Catalase inhibited fungicidal activity supporting a role for H(2)O(2) in fungus killing. In contrast, IL-8 and TNF-alpha levels were not affected by IL-15 suggesting that its effects were not mediated by these cytokines. Together, these results show that IL-15 is a potent stimulant of antifungal activities in human neutrophils, at least in part by a mechanism dependent on oxidative metabolism. (c) 2007 Elsevier Ltd. All rights reserved.

Interleukin-10 but not Transforming Growth Factor beta inhibits murine activated macrophages Paracoccidioides brasiliensis killing: Effect on H2O2 and NO production

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

Evaluation of pyraclostrobin and acibenzolar-S-methyl on common bacterial blight of snap bean

Assays were done under greenhouse conditions in order to evaluate the effect of pyraclostrobin (0.0375, 0.0750 and 0.150 mL.L-1) and acibenzolar-S-methyl (ASM) (0.025 g.L-1) in common bacterial blight on leaves of snap beans cultivar Braganca. These chemicals were sprayed at three different times: five days before; five days before + five days after; and five days after leaf inoculation with an isolate of Xanthomonas axonopodis pv. phaseoli. They were determinate the levels of polyphenoloxidase, peroxidase and total soluble proteins on inoculated and non-inoculated leaves of snap beans sprayed with pyraclostrobin (0.075 g.L-1) and ASM (0.025 g.L-1). All concentration of pyraclostrobin and ASM reduced the area under the disease progress curve (AUDPC) on leaves of snap beans, and the least AUDPC value was observed when this products were sprayed five days before + five days after inoculation. Higher levels of polyphenoloxidase, peroxidase and the total soluble proteins were observed on leaves sprayed with pyraclostrobin or ASM.

Culture-dependent and culture-independent characterization of microorganisms associated with Aedes aegypti (Diptera: Culicidae) (L.) and dynamics of bacterial colonization in the midgut

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Screening of bacterial strains for pectinolytic activity: characterization of the polygalacturonase produced by Bacillus sp

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

Surface Roughness and Bacterial Adherence to Resin Composites and Ceramics

Purpose: The aim of this study was to evaluate the surface roughness and the in vitro adherence of Streptococcus mutans to indirect aesthetic restorative materials that are uncoated with saliva.Materials and Methods: Four groups of restorative materials were evaluated according to material type: (1) microparticulate feldspathic ceramic; (2) leucite-reinforced feldspathic ceramic; (3) microhybrid resin composite and (4) microfilled resin composite. Twenty standardised samples of each material were produced. Roughness analysis (Ra, n = 10) was performed using a roughness analyser. Adhesion tests (n = 10) were carried out in 24-well plates; colony-forming units (CFU/mL) were evaluated. The mean values of roughness (mu m) and adherence (CFU/mL) for each group were subjected to an analysis of variance and a Tukey test.Results: The leucite-reinforced feldspathic ceramic was rougher and presented higher bacterial adherence than the microparticulate feldspathic ceramic. The resin composites were similar with regard to surface roughness and bacterial adherence.Conclusions: The microhybrid and microfilled resin composites were similar and the leucite-reinforced feldspathic ceramic was rougher and presented higher bacterial adherence than the microparticulate feldspathic ceramic.