Nanocomposites based on bacterial cellulose in combination with osteogenic growth peptide for bone repair: cytotoxic, genotoxic and mutagenic evaluations

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

Function inferences from a molecular structural model of bacterial ParE toxin

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

Performance and composition of bacterial communiies in anaerobic fluidized bed reactors for hydrogen production: Effects of organic loading rate and alkalinity

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Bacterial cellulose-hydroxyapatite composites with osteogenic growth peptide (OGP) or pentapeptide OGP on bone regeneration in critical-size calvarial defect model

This study aimed to evaluate the potential of bacterial cellulose-hydroxyapatite (BC-HA) composites associated with osteogenic growth peptide (OGP) or pentapeptide OGP(10–14) in bone regeneration in critical-size calvarial defects in mice. In this study, the BC-HA, BC-HA-OGP, and BC-HA-OGP(10–14) membranes were analyzed at 3, 7, 15, 30, 60, and 90 days. In each period, the specimens were evaluated by micro-computed tomography (µCT), descriptive histology, gene expression of bone biomarkers by qPCR and VEGFR-2 (vascular endothelial growth factor) quantification by ELISA. Three days post-operative, Runx2, Tnfrsf11b and Bglap bone biomarkers were upregulated mainly by BC-HA OGP and BC-HA OGP(10–14) membranes, suggesting an acceleration of the osteoblast differentiation/activity with the use of these biomaterials. At 60 and 90 days, a high percentage of bone formation was observed by µCT for BC-HA and BC-HA OGP(10–14) membranes. High expression of some bone biomarkers, such as Alpl, Spp1, and Tnfrsf11b, was also observed for the same membranes on days 60 and 90. In conclusion, the BC-HA membrane promoted a better bone formation in critical-size mice calvarial defects. Nevertheless, incorporation of the peptides at the concentration of 10−9 mol L−1 did not improve bone regeneration potential in the long-term.

CLSM assessment of tubule penetration and bacterial leakage evaluation of two resin-based sealer

Aim: The aims of this study were to assess the penetration of two endodontic sealers (salicylate and epoxy resin-based sealers) into dentinal tubules using CLSM; and to evaluate the bacterial leakage of roots filled with the same sealers associated with gutta-percha. Material and Methods: For sealer penetrability assessment, thirty bovine roots were instrumented and divided into three groups: AHP: EDTA + filling with AH Plus and gutta-percha (n=10), MTAF: EDTA + filling with MTA Fillapex and gutta-percha (n=10), control group: canals were not irrigated with EDTA and were filled with gutta-percha and AH Plus (n=5) or MTA Fillapex (n=5). Rhodamine B was added to the sealers in order to provide adequate fluorescence. The roots were transversely sectioned 3mm from the apex to enable CLSM analysis. Leakage was evaluated for turbidity of the broth in a split chamber model system for 30 days, using Enterococcus faecalis as a microbial marker. Thirty roots were instrumented and divided in four grupos: AHP: filling with AH Plus and gutta-percha (n=10); MTAF: filling with MTA Fillapex and gutta-percha (n=10); positive control: filling with gutta-percha without sealer (n = 5); negative control: sealing with cyanoacrylate to test the seal of the system (n = 5). Results: The medians for dentinal tubule penetration were 6.8% (AHP) and 6.6% (MTAF) (P = 0.82). The average time for bacterial leakage was 8 days in both experimental groups (P = 0.79). Conclusion: MTA Fillapex and AH Plus presented similar behavior regarding dentinal tubule penetration and bacterial leakage.

Effects of probiotic fermented milk on biofilms, oral microbiota, and enamel

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Eficiência da terapia fotodinâmica em Staphylococcus aureus e Escherichia coli

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Green and brown propolis: efficient natural biocides for the control of bacterial contamination of alcoholic fermentation of distilled beverage

This study aimed to evaluate the efficiency of natural biocides, brown and green propolis, for the control of bacterial contamination in the production of sugarcane spirit. The treatments consisted of brown and green propolis extracts, ampicillin, and a control and were assessed at the beginning and end of harvest season in ten fermentation cycles. In the microbiological analyses, the lactic acid bacteria were quantified in the inoculum before and after the treatment with biocides, and the viability of yeast cells during fermentation was evaluated. The levels of acids, glycerol, total residual reducing sugars, and ethanol were analyzed for the wine resulting from each fermentation cycle. A reduction in the number of bacterial contaminants in the inoculum in the treatments with the natural biocides was observed, but it did not affect the viability of yeast cells. The control of the contaminants led to the production of higher levels of ethanol and reduced acidity in the wine produced. The results of the use of brown and green propolis to control the growth microorganisms in the fermentation of sugarcane spirit can be of great importance for using alternative strategies to synthetic antibacterials in fermentation processes including other distilled beverage or spirits.

Biofilmes multiespécies de Candida Albicans associados com streptococcus mitis e streptococcus sanguinis: estudo in vitro e in vivo

Pós-graduação em Odontologia Restauradora - ICT

Ação da histatina 5, uma proteína antimicrobiana, no desenvolvimento de biofilmes de Candida Albicans

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

Control Methods and Evaluation of Bacterial Growth on Fresh and Cooled Stallion Semen

The penis and prepuce of the stallion have a high bacterial load on its surface, forming a natural microbial flora that contaminates the semen during ejaculation. Bacterial growth in semen may cause a decline on sperm quality, viability, and fertility and predisposes the occurrence of endometritis in inseminated mares. Thus, the aim of this study was to evaluate the effect of penile wash before semen collection, the addition of different commercial skim milk-based extenders containing antibiotics (BotuSemen and INRA96), and the removal of seminal plasma by filtration on the quality, viability, and bacterial proliferation on fresh and cooled stallion semen. Animals that were never submitted to penile wash before semen collection tended to have lower bacterial contamination in the ejaculate. Semen samples extended in BotuSemen showed superiority in total motility, progressive motility, average path velocity, and rapid sperm and lower bacterial contamination in relation to semen samples extended in INRA96 after 24 hours of cooling. No difference was found in these parameters between the storage temperatures (5 degrees C and 15 degrees C). Furthermore, the removal of seminal plasma by filtration reduced the bacterial load in semen after cooling. In conclusion, the penile wash before semen collection tended to reduce the bacterial growth in fresh semen. The use of a semen extender with appropriate antibiotics and removal of seminal plasma by filtration were effective in reducing the bacterial contamination and preserved the quality of cooled stallion semen. (C) 2015 Elsevier Inc. All rights reserved.

Susceptibility of Candida albicans and Candida glabrata biofilms to silver nanoparticles in intermediate and mature development phases

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

Different bacterial models for in vitro induction of non-cavitated enamel caries-like lesions: microhardness and polarized light miscroscopy analyses

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