Akie Fujimoto

Effect of S-PRG Eluate on Biofilm Formation and Enzyme Activity of Oral Bacteria.

Recently, the antibacterial activity of a composite resin containing prereacted glass ionomer (S-PRG) filler was revealed. We examined the effect of an S-PRG eluate on various biologic activities of Streptococcus mutans and Porphyromonas gingivalis. Adherence ability of S. mutans was evaluated by microtiter plate assay; protease and gelatinase activities of P. gingivalis were examined by synthetic substrate hydrolysis and gelatin film spot assay, respectively. Coaggregation of P. gingivalis with Fusobacterium nucleatum was also examined. S-PRG eluate was found to suppress streptococcal adherence. S-PRG eluate inhibited the protease and gelatinase activities of P. gingivalis and the coaggregation between P. gingivalis and F. nucleatum. These results indicate that S-PRG eluate suppresses streptococcal adherence and inhibits the protease and coaggregation activities of P. gingivalis. These findings may prompt research into novel strategies for preventing caries and periodontitis.

Lactobacillus salivarius WB21–containing tablets for the treatment of oral malodor: a double-blind, randomized, placebo-controlled crossover trial

OBJECTIVE This study evaluated the effect of probiotic intervention using lactobacilli on oral malodor. STUDY DESIGN We conducted a 14-day, double-blind, placebo-controlled, randomized crossover trial of tablets containing Lactobacillus salivarius WB21 (2.0 × 10(9) colony-forming units per day) or placebo taken orally by patients with oral malodor. RESULTS Organoleptic test scores significantly decreased in both the probiotic and placebo periods compared with the respective baseline scores (P < .001 and P = .002), and no difference was detected between periods. In contrast, the concentration of volatile sulfur compounds (VSCs) (P = .019) and the average probing pocket depth (P = .001) decreased significantly in the probiotic period compared with the placebo period. Bacterial quantitative analysis found significantly lower levels of ubiquitous bacteria (P = .003) and Fusobacterium nucleatum (P = .020) in the probiotic period. CONCLUSIONS These results indicated that daily oral consumption of tablets containing probiotic lactobacilli could help to control oral malodor and malodor-related factors.

Effects of S-PRG eluate on oral biofilm and oral malodor

OBJECTIVES This study evaluated the effects of a surface pre-reacted glass-ionomer (S-PRG) eluate on oral microbiota and dental biofilms in vitro, and on oral malodor and tongue bacterial loads clinically. STUDY DESIGN The effect of S-PRG eluate on the growth and survival of salivary bacteria was examined under both aerobic and anaerobic conditions; its ability to inhibit new biofilm formation and disrupt mature biofilms was also evaluated. The concentration of volatile sulfur compounds (VSCs) was measured using a portable sulfide monitor before and after rinsing with S-PRG eluate or distilled water. The number of bacteria on the tongue surface was calculated using a portable bacterial counter before and after tongue scraping with S-PRG eluate or distilled water. RESULTS No zone of inhibition was seen for S-PRG eluate against salivary microbiota under either aerobic or anaerobic conditions; however, treatment with ≥20% S-PRG eluate was sufficient to suppress biofilm formation relative to untreated controls. Mature biofilms were significantly disrupted following treatment with ≥60% S-PRG eluate relative to controls. Rinsing with S-PRG eluate significantly reduced the level of VSCs relative to baseline; this effect was not seen with distilled water alone. Waste fluids collected after oral rinsing with S-PRG eluate contained more bacteria than rinsing with distilled water alone. Finally, tongue scraping using S-PRG eluate was shown to significantly reduce the number of bacteria on the tongue surface. CONCLUSIONS S-PRG eluate inhibits biofilm formation and disrupts mature biofilms, although its antibacterial activity is limited. Oral rinsing and tongue cleaning with S-PRG eluate may reduce oral malodor by effectively removing oral bacteria from the oral cavity.

Involvement of mTOR in globular adiponectin-induced generation of reactive oxygen species

Abstract Globular adiponectin (gAd) induces the generation of reactive oxygen species (ROS) and nitric oxide (NO) in the murine macrophage cell line RAW 264. This study investigated the role of the mammalian target of rapamycin (mTOR) in gAd-induced ROS and NO generation. gAd stimulation induced phosphorylation of mTOR, which peaked at 20 min and dissolved rapidly. Inhibition of phosphatidylinositol 3-kinase activity with wortmannin suppressed gAd-induced phosphorylation of Akt and mTOR. Administration of rapamycin partially reduced gAd-induced generation of intracellular and mitochondrial ROS, but not release of NO. To further confirm the role of mTOR in gAd stimulation, the effect of the activators of AMP-activated protein kinase (AMPK) on gAd-induced mTOR phosphorylation was examined. Pre-treatment with three kinds of AMPK activators, AICAR, 2-deoxy-D-glucose and A-769662, suppressed gAd-induced mTOR phosphorylation. Furthermore, these AMPK activators significantly reduced gAd-evoked intracellular and mitochondrial ROS generation and NO release.

Inhibitory Effect of Enterococcus faecium WB2000 on Volatile Sulfur Compound Production by Porphyromonas gingivalis

Volatile sulfur compounds (VSCs) produced by oral anaerobes are the major compounds responsible for oral malodor. Enterococcus faecium WB2000 is recognized as an antiplaque probiotic bacterium. In this study, the effect of E. faecium WB2000 on VSC production by Porphyromonas gingivalis was evaluated, and the mechanism of inhibition of oral malodor was investigated. P. gingivalis ATCC 33277 was cultured in the presence of four lactic acid bacteria, including E. faecium WB2000. Subsequently, P. gingivalis ATCC 33277, W50, W83, and two clinical isolates were cultured in the presence or absence of E. faecium WB2000, and the emission of VSCs from spent culture medium was measured by gas chromatography. The number of P. gingivalis ATCC 33277 in mixed culture with E. faecium WB2000 decreased at 6 h, and the rate of decrease was higher than that in mixed cultures with the other lactic acid bacteria. The numbers of five P. gingivalis strains decreased at similar rates in mixed culture with E. faecium WB2000. The concentration of methyl mercaptan was lower in spent culture medium from P. gingivalis and E. faecium WB2000 cultures compared with that from P. gingivalis alone. Therefore, E. faecium WB2000 may reduce oral malodor by inhibiting the growth of P. gingivalis and neutralizing methyl mercaptan.

A Case of Oral Malodor: Improving the Motivation of Patients by Use ofBacterial Examination

Here, we report a case of oral malodor that was diagnosed by bacterial examination. The patient (a 32-year-old female) visited our breath clinic because a family member advised her to do so. Strong oral malodor was detected by several tests including an organoleptic test, a portable sulfide monitor, and gas chromatography. She noticed her oral malodor, but her motivation toward treatment was low. Even after explaining the cause of halitosis and the importance of oral hygiene, her motivation did not improve. So we applied a bacterial examination, and explained the results in detail. She understood how oral bacteria had caused the oral malodor, and she tried to do tooth brushing better. After a basic periodontal treatment, her oral condition improved and the number of periodontopathic bacteria reduced. She continued with careful tooth brushing even after the periodontal treatment, and her breath odor remarkably decreased. This case report indicates the usefulness of bacterial examination for motivating patients to improve their oral hygiene.

Involvement of suppressor of cytokine signaling-1 in globular adiponectin-induced granulocyte colony-stimulating factor in RAW 264 cell.

We previously demonstrated that treatment with a globular type of adiponectin (gAd) induced expression of granulocyte colony-stimulating factor (G-CSF) via the MEK/ERK signaling pathway in a murine macrophage cell line, RAW 264. In the present study, we investigated whether suppressor of cytokine signaling-1 (SOCS1) has roles in the regulation of gAd-induced G-CSF generation. Intracellular G-CSF generation induced by gAd treatment peaked after 10h and then attenuated. SOCS1 mRNA and protein were expressed at 1h and 4h after gAd treatment, respectively. Overexpression of SOCS1 reduced G-CSF generation and phosphorylation of ERK, JNK, and p38 MAPK in gAd-treated cells. While gAd treatment induced the translocation of STAT3 to the nucleus under control conditions, STAT3 stayed in the cytosol when SOCS1 was overexpressed. Additionally, knockdown of SOCS1 by interfering RNA caused levels of G-CSF to continue to rise beyond 10h after gAd treatment. These results suggest that SOCS1 is involved in providing negative feedback for gAd-induced production of G-CSF.

Lactobacillus salivarius WB21–containing tablets for the treatment of oral malodor: a double-blind, randomized, placebo-controlled crossover trial—reply to letter

1. The enrollment period was from June 2010 to September 2011, and the intervention and observation period was from June 2010 to November 2011. 2. We intended to collect 100 registrants, but 82 patients were finally registered. We confirmed the power of the main outcome based on sample size (see the Discussion section). 3. The interquartile ranges (IQRs) for the data in the figures are provided in the text. 4. As described in the Methods section, the organoleptic test (OLT) scores were estimated by 2 evaluators, and the means of these scores were used in the analysis. Therefore, the x-axis is represented as 0, 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 4.5, and 5, and the yaxis is the number of participants. 5. As described in the Methods section, we confirmed that the degree of coincidence of the 3 evaluators always exceeded 75%. 6. As described in the Methods section, malodor was assessed at least 5 hours after eating, drinking, smoking, and brushing or rinsing of the mouth. 7. This was a crossover trial. Both periods contained 23 participants. Therefore, 26% (6 of 23) of the patients in the probiotic period and 13% (3 of 23) of the patients in the placebo period improved to an OLT score 1. 8. Thankyou foryour comments.However, oralmalodor is typically generated directly from the oral cavity. 9. As described in the Methods and Discussion sections, the period effect was present in the tongue coating score (TCS). Longer washout periods may be required to evaluate changes in the TCS. 10. See the Discussion section. 11. The statistical analysis for the study was performed by a statistician. The period effect was present only in the tongue coating score. The meaning of “mystify” is unclear. Do you mean that you want to see the raw data? 12. The data are shown as median and IQR of the average probing pocket depth (PPD) in Table II. The statistical analysis was performed using the Wilcoxon signed-rank test. 13. We have used the reference literature. Please see the details in our previous reports containing the reference literature.