Search

Objective. To evaluate the effect of the combination of calcium hydroxide (Ca(OH)2) and a novel electrolyzed superoxidized solution at neutral pH, known as OxOral® on Enterococcus faecalis growth in root canals. Methods. Sixty human teeth were used, from which root canals were infected and randomly divided into the following treatment groups: saline solution, saline solution plus Ca(OH)2, OxOral®, and OxOral® plus Ca(OH)2. Results. A permanent reduction in bacterial growth was observed at days 1, 6, 12, and 18 after OxOral® plus Ca(OH)2 treatment from 4.4 ± 0.074 log 10 CFU / mL to 0.0 ± 0.001 log 10 CFU / mL. In addition, alkaline conditions maintenance was observed from application time (pH = 12.2 ± 0.033) to 18 d posttreatment (pH = 12.6 ± 0.083). Conclusion. The combination of OxOral® and Ca(OH)2 provides an alkaline pH and inhibits E. faecalis growth into the root canals. Our study opens the possibility for further research on the use of OxOral® in endodontic therapy. [ABSTRACT FROM AUTHOR]

The presence of Helicobacter pylori in the oral cavity has been associated to the failure of antimicrobial therapy in patients with gastrointestinal infection and the development of oral diseases. However, it has been reported that the maintenance of good oral hygiene can improve the therapeutic success rates, where the use of mouthwashes with anti-Helicobacter activity would help to achieve it. The aim was to evaluate the antimicrobial activity of OxOral® mouthwash against H. pylori and its effect on biofilm formation. The minimum inhibitory concentration (MIC) of OxOral® (pH = 6.4–7.5, ORP = 650–900 mV) against H. pylori was calculated testing serial dilutions 0.117–15 ppm against 1 × 108 CFU/mL of H. pylori (ATCC® 700824™) by broth microdilution method using 96‐well plates. The H. pylori biofilm formation was determined by the optical density measurement at 600 nm from coverslips stained with 0.1% crystal violet. The gene expression of ureA, luxS, flaA, omp18, and lpxD were analyzed by RT‐qPCR. OxOral® cytotoxicity was evaluated in a human gingival fibroblast cell line by MTT assay. MIC was of 3.75 ppm, with 99.7 ± 7.7% bacterial growth inhibition. In the negative control, the biofilm formation was observed, whereas when bacteria were treated with OxOral® at 0.234, 0.469, and 0.938 ppm, an inhibition of 35.5 ± 0.9%, 89.1 ± 1.2%, and 99.9 ± 5.5% were obtained, respectively. The gene expression analysis showed that flaA, omp18, and lpxD genes were down‐regulated with OxOral® compared with control (p < 0.05). Low cytotoxicity of 16.5 ± 7.6% was observed at the highest dose (15 ppm); no significant differences were observed from 15 to 0.469 ppm compared to the control of untreated cells (p > 0.05). Our results reveal an important anti-Helicobacter activity of OxOral® and open the possibility of its therapeutic use new studies, which would increase the success rate of conventional therapies against H. pylori. [ABSTRACT FROM AUTHOR]

Helicobacter pylori is a spiral Gram-negative bacterium associated with inflammation of the gastric mucosa, peptic ulcer, and gastric adenocarcinoma, whose treatment has failed due to antibiotic resistance and side effects. Furthermore, because there are no vaccines effective against H. pylori, an appropriate vaccine design targeting conserved/essential genes must be identified. In the present study, a H. pylori 50–52 kDa immunogen-derived peptide antigen with the sequence Met-Val-Thr-Leu-Ile-Asn-Asn-Glu (MVTLINNE) was used to immunize against H. pylori infection. For this, mice received an intraperitoneal injection of 100 μg of H. pylori peptide on the first week, followed by two weekly subcutaneous reinforcements and further 109 bacteria administration in the drinking water for 3 weeks. Thymic cells proliferative responses to concanavalin A, serum levels of IL-2, IL-4, IL-6, IL-10, IL-17, IFN-γ, and TNF-α cytokines, and IgG1, IgG2a, IgG2b, IgG3 IgM, and IgA immunoglobulins were evaluated. Significant (p<0.05) increases on lymphoproliferation and spleen weights after immunization were observed. In contrast, infection significantly (p<0.05) decreased lymphoproliferation, which was recovered in immunized mice. In addition, levels of serum TH1 and TH2 cytokines were not altered after immunization, except for the significant increase in IL-6 production in immunized and/or infected animals. Moreover, immunization correlated with plasma secretory IgA and IgG, whereas infection alone only elicited IgM antibodies. Peptide immunization protected 100% of mice against virulent H. pylori. MVTLINNE peptide deserves further research as an approach to the prophylaxis of H. pylori infection. [ABSTRACT FROM AUTHOR]

Helicobacter pylori is an infectious agent commonly associated with gastrointestinal diseases. The use of probiotics to treat this infection has been documented, however, their potential antimicrobial metabolites have not yet been investigated. In the present study, the effect of reuterin produced by Lactobacillus reuteri on H. pylori growth and virulence gene expression was evaluated. It was observed that reuterin caused significant (P < 0.05) H. pylori growth inhibition at concentrations from 0.08 to 20.48 mM, with minimal inhibitory concentrations (MICs) of 20.48 mM for H. pylori ATCC700824 and 10.24 mM for H. pylori ATCC43504. In a reuterin bacterial killing assay, it was observed that half of the MIC value for H. pylori (ATCC700824) significantly (P < 0.01) reduced colony numbers from 5.65 ± 0.35 to 3.78 ± 0.35 Log10 CFU/mL after 12 h of treatment and then increased them to 5.25 ± 0.23 Log10 CFU/mL at 24 h; at its MIC value (20.48 mM), reuterin abrogated (P < 0.01) H. pylori (ATCC700824) growth after 20 h of culture. In addition, reuterin significantly (P < 0.01) reduced H. pylori (ATCC 43504) colony numbers from 5.65 ± 0.35 to 4.1 ± 0.12 Log10 CFU/mL from 12 to 24 h of treatment and abrogated its growth at its MIC value (10.24 mM), after 20 h of treatment. Reuterin did not alter normal human gastric Hs738.St/Int cell viability at the concentrations tested for H. pylori strains. Furthermore, 10 μM reuterin was shown to significantly (P < 0.01) reduce mRNA relative expression levels of H. pylori virulence genes vacA and flaA at 3 h post-treatment, whose effect was higher at 6 h post-treatment, as measured by RT-qPCR. The observed direct antimicrobial effect and the downregulation of expression of virulence genes on H. pylori by reuterin may contribute to the understanding of the mechanisms of action of probiotics against H. pylori. [ABSTRACT FROM AUTHOR]

The variability in Helicobacter pylori vacA and cagA genes has been related to the progression of the gastrointestinal disease; also the presence of H. pylori in the oral cavity has been associated with periodontal disease in adults, but, in children without dyspeptic symptoms, little is known about this. We evaluated the prevalence of H. pylori and the presence of vacA/cagA genotypes in the oral cavity of Mexican children without dyspeptic symptoms. The gingival status was measured, and dental plaque samples (n=100) were taken. 38% of children were positive for H. pylori 16S rRNA gene by qPCR. A significant association between H. pylori oral infection and gingival status was observed (P<0.001). In 34.6% (9/26) of mild gingivitis cases, s1m2 genotype was found, while s1m1 was typed in 50% (3/6) of moderate gingivitis. The cagA prevalence among H. pylori-positive children was 80.8% (21/26), 83.3% (5/6), and 16.7% (1/6) of cases of mild gingivitis, moderate gingivitis, and nongingivitis, respectively (P<0.001). The s1m1/cagA+ combinational genotype was the most detected in children with gingivitis. Our results suggest that the prevalence of H. pylori and detection of vacA/cagA genotypes-associated gastrointestinal disease in the oral cavity could be related to the progression of gingivitis in asymptomatic children. [ABSTRACT FROM AUTHOR]

Αlpha-solanine (α-solanine) is a glycoalkaloid present in potato (Solanum tuberosum). It has been of particular interest because of its toxicity and potential teratogenic effects that include abnormalities of the central nervous system, such as exencephaly, encephalocele, and anophthalmia. Various types of cell culture have been used as experimental models to determine the effect of α-solanine on cell physiology. The morphological changes in the mesenchymal stem cell upon exposure to α-solanine have not been established. This study aimed to describe a reliable and reproducible model for assessing the structural changes induced by exposure of mouse bone marrow mesenchymal stem cells (MSCs) to different concentrations of α-solanine for 24 h. The results demonstrate that nonlethal concentrations of α-solanine (2–6 μM) changed the morphology of the cells, including an increase in the number of nucleoli, suggesting elevated protein synthesis, and the formation of spicules. In addition, treatment with α-solanine reduced the number of adherent cells and the formation of colonies in culture. Immunophenotypic characterization and staining of MSCs are proposed as a reproducible method that allows description of cells exposed to the glycoalkaloid, α-solanine. [ABSTRACT FROM AUTHOR]

Introduction: Epidermal growth factor (EGF) and basic fibroblast growth factor (bFGF) play an important role in extracellular matrix mineralization, a complex process required for proper bone regeneration, one of the biggest challenges in dentistry. The purpose of this study was to evaluate the osteogenic potential of EGF and bFGF on dental pulp stem cells (DPSCs). Material and methods: Human DPSCs were isolated using CD105 magnetic microbeads and characterized by flow cytometry. To induce osteoblast differentiation, the cells were cultured in osteogenic medium supplemented with EGF or bFGF at a low concentration. Cell morphology and expression of CD146 and CD10 surface markers were analyzed using fluorescence microscopy. To measure mineralization, an alizarin red S assay was performed and typical markers of osteoblastic phenotype were evaluated by RT-PCR. Results: EGF treatment induced morphological changes and suppression of CD146 and CD10 markers. Additionally, the cells were capable of producing calcium deposits and increasing the mRNA expression to alkaline phosphatase (ALP) and osteocalcin (OCN) in relation to control groups (p < 0.001). However, bFGF treatment showed an inhibitory effect. Conclusion: These data suggests that DPSCs in combination with EGF could be an effective stem cell-based therapy for bone tissue engineering applications in periodontics and oral implantology. [ABSTRACT FROM AUTHOR]