Objective:To investigate the effect of Phyllanthus emblica(P.emblica) Linn,ethanolic extract on the adhesion of Candida albicans(C.albicans) to human buccal epithelial cells(BECs) and denture acrylic surfaces.Methods:...Objective:To investigate the effect of Phyllanthus emblica(P.emblica) Linn,ethanolic extract on the adhesion of Candida albicans(C.albicans) to human buccal epithelial cells(BECs) and denture acrylic surfaces.Methods:Human BECs and transparent acrylic strips were pretreated with ethanolic extract solution of P.emblica fruits at concentration ranged from 18.7 to 300 mg/mL.After washing BECs and the strips were inoculated with three strains of C.albicans (ATCC 10281 and two clinical isolates)(10~7 cells/mL).Normal saline solution(NSS) and 0.2% chlorhexidine gluconate were used as negative and positive controls,respectively.BECs were harvested on 12μm-polycarbonate filters(Millipore,USA).The membrane filters and the strips were stained with Gram stain.Adherent yeast cells on 100 randomly selected epithelial cells and 20 randomly selected fields on each strip were counted under microscope.The statistical significance was calculated by Kruskal-Wallis and Tukey tests at a significant level of P【0.05. Results:Significant lower numbers of all strains of yeasts adhering to BECs and acrylic strips were observed after exposure to 75-300 mg/mL of plant extract compared with NSS.Conclusions: The present study demonstrates that P.emblica ethanolic extract interferes with the adhesion of C. albicans to BECs and denture acrylic surfaces in vitro.展开更多
Objective: To investigate the effect of the roselle calyx extract(RCE)(Hibiscus sabdariffa L.) on the in vitro viability and biofilm formation ability of oral pathogenic bacteria. Methods:RCE was prepared by soaking r...Objective: To investigate the effect of the roselle calyx extract(RCE)(Hibiscus sabdariffa L.) on the in vitro viability and biofilm formation ability of oral pathogenic bacteria. Methods:RCE was prepared by soaking roselle calyx powder with ethyl alcohol for 24 h at room temperature. After centrifugation, the extract was lyophilized. Then, the extract was dissolved in phosphate-buffered saline, the p H was adjusted, and the extract was aseptically filtered. We used Streptococcus mutans, Streptococcus sanguinis, Lactobacillus casei, Actinomyces naeslundii, Aggregatibacter actinomycetemcomitans, Fusobacterium nucleatum, Porphyromonas gingivalis and Prevotella intermedia in this study. The antibacterial activity of the RCE was determined by treating the cells of these bacteria with the extract for 10 or 20 min at room temperature. The minimum inhibitory concentration(MIC) and minimum bactericidal concentration was determined using the micro dilution method, and the effect of the RCE on the ability to form biofilm was determined using a polystyrene micro plate assay. In addition, we used the WST-1 assay to determine the cytotoxicity of the RCE on HGF, Ca9-22 and KB cells. Results: The RCE had antibacterial activity against oral bacteria used in this study. In particular, most significant antibacterial activity was observed against Fusobacterium nucleatum, Prevotella intermedia and Porphyromonas gingivalis. The MIC and minimum bactericidal concentration were 7.2 mg/m L–28.8 mg/m L and 14.4 to >57.6 mg/m L. The RCE had an inhibitory effect on biofilm formation at the MIC and sub-MIC levels. In addition, the RCE had low cytotoxic effects on HGF, Ca9-22 and KB cells. Conclusions: Thus, our results indicate that the RCE may be used for preventing oral diseases.展开更多
The prevalence of periodontal disease among pregnant women increases with gestational age. Therefore, oral health education in the early stage of pregnancy should prevent periodontal disease and decrease the risk of a...The prevalence of periodontal disease among pregnant women increases with gestational age. Therefore, oral health education in the early stage of pregnancy should prevent periodontal disease and decrease the risk of an adverse pregnancy outcome such as preterm delivery and low birth weight. However, there has been no study on oral health care intervention for prevention of periodontal disease during pregnancy. The purpose of this study was to examine the efficiency of an oral health education program on periodontal disease among Japanese low-risk pregnant women. A total of 207 pregnant women before 20 weeks of gestation were recruited. The first 131 of them were assigned to the control group and the remaining 76 to the experimental group. The experiment participants received an oral health education program including the toothpick brushing method in their early stage of pregnancy. Improvement of the self-assessment score of periodontal symptoms was used as a binary outcome variable. A logistic regression analysis indicated that the intervention (OR = 3.83) and proficiency of the toothpick brushing method (OR = 24.93) were statistically significant predictors of the outcome in the late stage of pregnancy. The positive outcome appeared after practice of the toothpick method brushing for 20 or more weeks, and was associated with the decrease in the log-transformed proportion of the count of Candida species in salivary microbiota (p = 0.026).展开更多
A previous study demonstrated that alexidine has greater affinity for the major virulence factors of bacteria than chlorhexidine. The aim of this study was to compare the antimicrobial activity of 1% alexidine with th...A previous study demonstrated that alexidine has greater affinity for the major virulence factors of bacteria than chlorhexidine. The aim of this study was to compare the antimicrobial activity of 1% alexidine with that of 2% chlorhexidine using Enterococcus faecalis.infected dentin blocks. Sixty bovine dentin blocks were prepared and randomly divided into six groups of 10 each. E. faecalis was inoculated on 60 dentin blocks using the Luppens apparatus for 24 h and then the dentin blocks were soaked in 2% chlorhexidine or 1% alexidine solutions for 5 and 10 min, respectively. Sterile saline was used as a control. The antimicrobial efficacy was assessed by counting the number of bacteria adhering to the dentin surface and observing the degradation of bacterial shape or membrane rupture under a scanning electron microscope. Significantly fewer bacteria were observed in the 2% chlorhexidine- or 1% alexidine-soaked groups than in the control group （P^O.05）. However, there was no significant difference in the number of bacteria adhering to the dentinal surface between the two experimental groups or between the two soaking time groups （P＞0.05）. Ruptured or antiseptic-attached bacteria were more frequently observed in the lO-min-soaked chlorhexidine and alexidine groups than in the 5-min-soaked chlorhexidine and alexidine groups. In conclusion, lO-min soaking with 1% alexidine or 2% chlorhexidine can be effective against E. faecalis infection.展开更多
Objective:To determine the anticandidal activities of Salvia officinalis L.(S.officinalis)essential oil against Candida albicans(C.albicans)and the inhibitory effects on the adhesion of C.albicans to polymethyl methac...Objective:To determine the anticandidal activities of Salvia officinalis L.(S.officinalis)essential oil against Candida albicans(C.albicans)and the inhibitory effects on the adhesion of C.albicans to polymethyl methacrylate(PMMA)resin surface.Methods:Disc diffusion method was first used to test the anticandidal activities of the S.officinalis L.essential oil against the reference strain(ATCC 90028)and 2 clinical strains of C.albicans.Then the minimal inhibitory concentration(MIC)and minimal lethal concentration(MLX)were determined by modified membrane method.The adhesion of C.albicans to PMMA resin surface was assessed after immersion with S.officinalis L.essential oil at various concentrations of 1XMIC.0.5XMIC and 0.25XMIC at room temperature for30 min.One-way ANOVA was used to compare the Candida cell adhesion with the pretreatment agents and Tukey's test was used for multiple comparisons.Results:5.officinalis L.essential oil exhibited anticandidal activity against all strains of C.albicans with inhibition zone ranging from 40.5 mm to 19.5 mm.The MIC and MLC of the oil were determined as 2.780 g/L against all test strains.According to the effects on C.albicans adhesion to PMMA resin surface,it was found that immersion in the essential oil at concentrations of 1XMIC(2.780 g/L).0.5XMIC(1.390 g/L)and0.25XMIC(0.695 g/L)for 30 min significantly reduced the adhesion of all 3 test strains to PMMA resin surface in a dose dependent manner(P<0.05).Conclusions:S.officinalis L.essential oil exhibited anticandidal activities against C.albicans and had inhibitory effects on the adhesion of the cells to PMMA resin surface.With further testing and development,S.officinalis essential oil may be used as an antifungal denture cleanser to prevent candidal adhesion and thus reduce the risk of candida-associated denture stomatitis.展开更多
Objective:To determine the antimicrobial effects of grape seed on peri-implantitis microflora.Methods:The grape seed extract was tested against peri-implantitis microflora most commonly found in craniofacial implants ...Objective:To determine the antimicrobial effects of grape seed on peri-implantitis microflora.Methods:The grape seed extract was tested against peri-implantitis microflora most commonly found in craniofacial implants including reference strains of Staphylococcus aureus(S.aureus),Escherichia coli(E.coli),Candida albicans(C.albicans)and clinical strains of S.aureus,Klebsiella pneumonia(K.pneumonia)and Candida parapsilosis(C.parapsilosis)by disk diffusion test.Minimum inhibitory concentrations(MIC)and minimum cidal concentrations(MCC)were determined using modified agar dilution millpore method.The extract was further combined with polyethylene glycol and propylene glycol,and was tested for antimicrobial effects.Results:Grape seed extract showed positive inhibitory effects with S.aureus at MIC of 0.625 mg/mL and MCC of1.25 mg/mL respectively.However the extracts showed minimal or no reactivity against strains of E.coli,K.pneumonia,C.parapsilosis and C.albicans.The use of grape seed extract in combination with polyethylene glycol and propylene glycol also showed dose dependent inhibitory effect on S.aureus.Conclusions:The results of the study showed that grape seed has potential antimicrobial effects which can be further studied and developed to be used in the treatment of infected skinabutment interface of craniofacial implants.展开更多
Objective: To investigate the composition of the salivary microbiome of 50 healthy Thai children. Methods: A total 76 provinces in Thailand are grouped into 5 geographical clusters based on unique economics, foods and...Objective: To investigate the composition of the salivary microbiome of 50 healthy Thai children. Methods: A total 76 provinces in Thailand are grouped into 5 geographical clusters based on unique economics, foods and lifestyles. Geographical locations and the results of an oral assessment were also considered. Genomic DNA was extracted from stimulated saliva samples. Subsequently, amplicon libraries were prepared by 16 S Metagenomic Sequencing Library Preparation. The amplicons were sequenced using an Illumina Miseq platform followed by bioinformatics and statistical analyses.Results: The correlation between oral hygiene status and caries history varied from r^2=0.887 to r^2=0.999 in the geographical groups, suggesting oral hygiene status a strong association between caries history. Twenty taxonomic groups were found in all subjects and constituted 93.6%-96.5% of the microbiome. Of these, genus Veillonella and Prevotella showed significant differences in their proportions between the geographical groups(P<0.05). Furthermore, the proportion of Veillonella parvula, as well as Rothia aeria and Rothia dentocariosa tended to increase with worse oral hygiene status, which was also related to higher dental caries history.Conclusions: The differences in the salivary microbiome as related to geographic regions suggest that environmental factors, which may include dietary habits, could influence the predominant bacteria found in the mouth of Thai children, especially the genus Veillonella and Prevotella. The ratio of Veillonella parvula, Rothia aeria and Rothia dentocariosa may be indicators of worse oral hygiene status and future caries in this population.展开更多
Cryptotanshinone (CT), a major tanshinone of medicinal plant Salvia miltiorrhiza Bunge, demonstrated effective in vitro antibacterial activity against all oral bacteria tested in this experiment. The antibacterial act...Cryptotanshinone (CT), a major tanshinone of medicinal plant Salvia miltiorrhiza Bunge, demonstrated effective in vitro antibacterial activity against all oral bacteria tested in this experiment. The antibacterial activities of CT against oral bacteria were assessed using the checkerboard and time-kill methods to evaluate the synergistic effects of treatment with ampicillin or gentamicin. The CT was determined against oral pathogenic bacteria with MIC and MBC values ranging from 0.5 to 16 and 1 to 64 μg/mL;for am- picillin from 0.0313 to 16 and 0.125 to 32 μg/mL;for gentamicin from 2 to 256 and 4 to 512 μg/mL respectively. The range of MIC50 and MIC90 were 0.0625 - 8 μg/mL and 1 - 64 μg/mL, respectively. The combination effects of CT with antibiotics were synergistic (FIC index < 0.5) against tested oral bacteria except additive, Streptococcus sobrinus, S. criceti, and Actinobacillus actinomycetemcomitans (FIC index < 0.75 - 1.0). The MBCs were shown reducing ≥4 - 8-fold, indicating a synergistic effect as defined by a FBCI of ≤0.5. Furthermore, a time-kill study showed that the growth of the tested bacteria was completely attenuated after 3 - 6 h of treatment with the 1/2 MIC of CT, regardless of whether it was administered alone or with ampicillin or gentamicin. The results suggest that CT could be employed as a natural antibacterial agent against cariogenic and periodontopathogenic bac- teria.展开更多
Objective:To evaluate the level of salivary Mutatis streptococci(MS) after rinsing with xylitol, fluoride,and a combination of xylitol and fluoride solutions,compared with distilled water. Methods:Eighty healthy 8-9 y...Objective:To evaluate the level of salivary Mutatis streptococci(MS) after rinsing with xylitol, fluoride,and a combination of xylitol and fluoride solutions,compared with distilled water. Methods:Eighty healthy 8-9 years old subjects with high level of MS(】 10~5 CFU/mL) were equally divided into 4 groups.Subjects rinsed their moutlis for 1 min with 10 mL of 0.05%(w/v) sodium fluoride(NaF),12.5%(w/v) xylitol or 0.05%(w/v) NoF + 12.5%(w/v) xylitol 3 times daily over 10 weeks.Distilled water rinsed group served as a control.Paraffin-stimulated whole saliva samples were collected at baseline,5 weeks,and 10 weeks after rinsing to determine the level of salivary MS by culturing on Mitis Salivarius Bacitracin agar.The statistical significance was calculated by Kruskol Wallis,Mann Whitney U,and Wilcoxon signed-rank tests at a significant level of P【 0.05.Results:Significant reductions in MS count were observed in subjects using 0.05%NaF + 12.5%xylitol over other groups within 5 weeks and after 10 weeks and 12.5%xylitol alone after 10 weeks compared with baseline.Conclusions:The present study provides evidence for the inhibitory effect of xylitol,used in combination with fluoride,delivered in the form of mouthrinse, on salivary MS in the group of schoolchildren.展开更多
Streptococcus mutans(S. mutans), a major aetiologic agent of dental caries, is involved in systemic diseases, such as bacterial endocarditis, if it enters the bloodstream through temporary bacteraemia. Interleukin(IL...Streptococcus mutans(S. mutans), a major aetiologic agent of dental caries, is involved in systemic diseases, such as bacterial endocarditis, if it enters the bloodstream through temporary bacteraemia. Interleukin(IL)-1β, a proinflammatory cytokine, is related to the host defences against pathogens, and its synthesis, maturation, and secretion are tightly regulated by the activation of the inflammasome, an inflammatory signalling complex. This study examined the signalling mechanism of IL-1β secretion and the inflammasome pathway induced by S. mutans to explain the molecular mechanism through which systemic infection by oral streptococci can occur. After infection of THP-1 cells with S. mutans, the expression of inflammasome components was detected using various methods. S. mutans induced IL-1β secretion via caspase-1 activation, and S. mutans-induced IL-1β secretion required absent in melanoma(AIM2), NLR family pyrin domain-containing 3(NLRP3) and NLR family CARD domain-containing 4(NLRC4)inflammasome activation. In particular, the S. mutans-induced NLRP3 inflammasome was mediated by adenosine triphosphate(ATP) release, potassium depletion and lysosomal damage. Our study provides novel insight into the innate immune response against S. mutans infection.展开更多
Polyalkenoate cement(PAC)is a promising material for regenerative hard tissue therapy.The ionically rich glass component of PAC encourages bioactive interaction via.the release of essential ions.However,PAC bioactivit...Polyalkenoate cement(PAC)is a promising material for regenerative hard tissue therapy.The ionically rich glass component of PAC encourages bioactive interaction via.the release of essential ions.However,PAC bioactivity is restricted owing to(i)structurally inherent cationic network formers and(ii)surface bacterial biofilm formation.These two factors cause a deficiency in ion release,further complicated by secondary infections and premature therapeutic failure.Here,a multivalent zwitterionic network modifier(mZM)is presented for upregulation of ionic exchange and bioactivity enhancement.By introducing a non-zero charged mZM into PACs,an increase in the proportion of non-bridging oxygen occurs.The network modification promotes ion channel formation,causing a multiple-fold increase in ion release and surface deposition of hydroxy-carbonate apatite(ca.74%).Experiments ex vivo and animal models also demonstrate the efficient remineralization ability of the mZM.Furthermore,divalent cationic interaction results in bacterial biofilm reduction(ca.68%)while also influencing a shift in the biofilm species composition,which favors commensal growth.Therefore,PAC modification with mZM offers a promising solution for upregulation of bioactivity,even aiding in customization by targeting site-specific regenerative therapy in future applications.展开更多
Invasive infection caused by Streptococcus pyogenes emm89 strains has been increasing in several countries linked to a recently emergent clade of emm89 strains,designated clade 3.In Japan,the features of emm89 S.pyoge...Invasive infection caused by Streptococcus pyogenes emm89 strains has been increasing in several countries linked to a recently emergent clade of emm89 strains,designated clade 3.In Japan,the features of emm89 S.pyogenes strains,such as clade classification,remains unknown.In this study,we collected emm89 strains isolated from both streptococcal toxic shock syndrome(STSS)(89 STSS isolates)and noninvasive infections(72 non-STSS isolates)in Japan from 2011 to 2019,and conducted wholegenome sequencing and comparative analysis,which resulted in classification of a large majority into clade 3 regardless of disease severity.In addition,invasive disease-associated factors were found among emm89 strains,including mutations of control of virulence sensor,and absence of the hylP1 gene encoding hyaluronidase.These findings provide new insights into genetic features of emm89 strains.展开更多
文摘Objective:To investigate the effect of Phyllanthus emblica(P.emblica) Linn,ethanolic extract on the adhesion of Candida albicans(C.albicans) to human buccal epithelial cells(BECs) and denture acrylic surfaces.Methods:Human BECs and transparent acrylic strips were pretreated with ethanolic extract solution of P.emblica fruits at concentration ranged from 18.7 to 300 mg/mL.After washing BECs and the strips were inoculated with three strains of C.albicans (ATCC 10281 and two clinical isolates)(10~7 cells/mL).Normal saline solution(NSS) and 0.2% chlorhexidine gluconate were used as negative and positive controls,respectively.BECs were harvested on 12μm-polycarbonate filters(Millipore,USA).The membrane filters and the strips were stained with Gram stain.Adherent yeast cells on 100 randomly selected epithelial cells and 20 randomly selected fields on each strip were counted under microscope.The statistical significance was calculated by Kruskal-Wallis and Tukey tests at a significant level of P【0.05. Results:Significant lower numbers of all strains of yeasts adhering to BECs and acrylic strips were observed after exposure to 75-300 mg/mL of plant extract compared with NSS.Conclusions: The present study demonstrates that P.emblica ethanolic extract interferes with the adhesion of C. albicans to BECs and denture acrylic surfaces in vitro.
基金supported by scholarship from Futoku Foundation and Hokkaido Gas Co.Ltd
文摘Objective: To investigate the effect of the roselle calyx extract(RCE)(Hibiscus sabdariffa L.) on the in vitro viability and biofilm formation ability of oral pathogenic bacteria. Methods:RCE was prepared by soaking roselle calyx powder with ethyl alcohol for 24 h at room temperature. After centrifugation, the extract was lyophilized. Then, the extract was dissolved in phosphate-buffered saline, the p H was adjusted, and the extract was aseptically filtered. We used Streptococcus mutans, Streptococcus sanguinis, Lactobacillus casei, Actinomyces naeslundii, Aggregatibacter actinomycetemcomitans, Fusobacterium nucleatum, Porphyromonas gingivalis and Prevotella intermedia in this study. The antibacterial activity of the RCE was determined by treating the cells of these bacteria with the extract for 10 or 20 min at room temperature. The minimum inhibitory concentration(MIC) and minimum bactericidal concentration was determined using the micro dilution method, and the effect of the RCE on the ability to form biofilm was determined using a polystyrene micro plate assay. In addition, we used the WST-1 assay to determine the cytotoxicity of the RCE on HGF, Ca9-22 and KB cells. Results: The RCE had antibacterial activity against oral bacteria used in this study. In particular, most significant antibacterial activity was observed against Fusobacterium nucleatum, Prevotella intermedia and Porphyromonas gingivalis. The MIC and minimum bactericidal concentration were 7.2 mg/m L–28.8 mg/m L and 14.4 to >57.6 mg/m L. The RCE had an inhibitory effect on biofilm formation at the MIC and sub-MIC levels. In addition, the RCE had low cytotoxic effects on HGF, Ca9-22 and KB cells. Conclusions: Thus, our results indicate that the RCE may be used for preventing oral diseases.
文摘The prevalence of periodontal disease among pregnant women increases with gestational age. Therefore, oral health education in the early stage of pregnancy should prevent periodontal disease and decrease the risk of an adverse pregnancy outcome such as preterm delivery and low birth weight. However, there has been no study on oral health care intervention for prevention of periodontal disease during pregnancy. The purpose of this study was to examine the efficiency of an oral health education program on periodontal disease among Japanese low-risk pregnant women. A total of 207 pregnant women before 20 weeks of gestation were recruited. The first 131 of them were assigned to the control group and the remaining 76 to the experimental group. The experiment participants received an oral health education program including the toothpick brushing method in their early stage of pregnancy. Improvement of the self-assessment score of periodontal symptoms was used as a binary outcome variable. A logistic regression analysis indicated that the intervention (OR = 3.83) and proficiency of the toothpick brushing method (OR = 24.93) were statistically significant predictors of the outcome in the late stage of pregnancy. The positive outcome appeared after practice of the toothpick method brushing for 20 or more weeks, and was associated with the decrease in the log-transformed proportion of the count of Candida species in salivary microbiota (p = 0.026).
基金supported by the National Research Foundation(NRF) of Korea funded by the Ministry of Education,Science and Technology(MEST) (No.2009-0086835,2011-0014231,2012-0008693:Drs KY Kum,SH Han and SW Chang),South Korea
文摘A previous study demonstrated that alexidine has greater affinity for the major virulence factors of bacteria than chlorhexidine. The aim of this study was to compare the antimicrobial activity of 1% alexidine with that of 2% chlorhexidine using Enterococcus faecalis.infected dentin blocks. Sixty bovine dentin blocks were prepared and randomly divided into six groups of 10 each. E. faecalis was inoculated on 60 dentin blocks using the Luppens apparatus for 24 h and then the dentin blocks were soaked in 2% chlorhexidine or 1% alexidine solutions for 5 and 10 min, respectively. Sterile saline was used as a control. The antimicrobial efficacy was assessed by counting the number of bacteria adhering to the dentin surface and observing the degradation of bacterial shape or membrane rupture under a scanning electron microscope. Significantly fewer bacteria were observed in the 2% chlorhexidine- or 1% alexidine-soaked groups than in the control group （P^O.05）. However, there was no significant difference in the number of bacteria adhering to the dentinal surface between the two experimental groups or between the two soaking time groups （P＞0.05）. Ruptured or antiseptic-attached bacteria were more frequently observed in the lO-min-soaked chlorhexidine and alexidine groups than in the 5-min-soaked chlorhexidine and alexidine groups. In conclusion, lO-min soaking with 1% alexidine or 2% chlorhexidine can be effective against E. faecalis infection.
基金Supported by Maxillofacial Prosthetic Service Research Fund,Faculty of Dentistry,Mahidol University,Bangkok,Thailand(Grant No.496/2011)
文摘Objective:To determine the anticandidal activities of Salvia officinalis L.(S.officinalis)essential oil against Candida albicans(C.albicans)and the inhibitory effects on the adhesion of C.albicans to polymethyl methacrylate(PMMA)resin surface.Methods:Disc diffusion method was first used to test the anticandidal activities of the S.officinalis L.essential oil against the reference strain(ATCC 90028)and 2 clinical strains of C.albicans.Then the minimal inhibitory concentration(MIC)and minimal lethal concentration(MLX)were determined by modified membrane method.The adhesion of C.albicans to PMMA resin surface was assessed after immersion with S.officinalis L.essential oil at various concentrations of 1XMIC.0.5XMIC and 0.25XMIC at room temperature for30 min.One-way ANOVA was used to compare the Candida cell adhesion with the pretreatment agents and Tukey's test was used for multiple comparisons.Results:5.officinalis L.essential oil exhibited anticandidal activity against all strains of C.albicans with inhibition zone ranging from 40.5 mm to 19.5 mm.The MIC and MLC of the oil were determined as 2.780 g/L against all test strains.According to the effects on C.albicans adhesion to PMMA resin surface,it was found that immersion in the essential oil at concentrations of 1XMIC(2.780 g/L).0.5XMIC(1.390 g/L)and0.25XMIC(0.695 g/L)for 30 min significantly reduced the adhesion of all 3 test strains to PMMA resin surface in a dose dependent manner(P<0.05).Conclusions:S.officinalis L.essential oil exhibited anticandidal activities against C.albicans and had inhibitory effects on the adhesion of the cells to PMMA resin surface.With further testing and development,S.officinalis essential oil may be used as an antifungal denture cleanser to prevent candidal adhesion and thus reduce the risk of candida-associated denture stomatitis.
文摘Objective:To determine the antimicrobial effects of grape seed on peri-implantitis microflora.Methods:The grape seed extract was tested against peri-implantitis microflora most commonly found in craniofacial implants including reference strains of Staphylococcus aureus(S.aureus),Escherichia coli(E.coli),Candida albicans(C.albicans)and clinical strains of S.aureus,Klebsiella pneumonia(K.pneumonia)and Candida parapsilosis(C.parapsilosis)by disk diffusion test.Minimum inhibitory concentrations(MIC)and minimum cidal concentrations(MCC)were determined using modified agar dilution millpore method.The extract was further combined with polyethylene glycol and propylene glycol,and was tested for antimicrobial effects.Results:Grape seed extract showed positive inhibitory effects with S.aureus at MIC of 0.625 mg/mL and MCC of1.25 mg/mL respectively.However the extracts showed minimal or no reactivity against strains of E.coli,K.pneumonia,C.parapsilosis and C.albicans.The use of grape seed extract in combination with polyethylene glycol and propylene glycol also showed dose dependent inhibitory effect on S.aureus.Conclusions:The results of the study showed that grape seed has potential antimicrobial effects which can be further studied and developed to be used in the treatment of infected skinabutment interface of craniofacial implants.
基金supported by the Japan Society for the Promotion of Science(JSPS)Fellows(15J30007)Scientific Research from KAKENHI(Grant number:26462793)the 2014-2015 and 2016-2017 Research Project of the Research Institute of Personalized Health Sciences,Health Sciences University of Hokkaido,research grant 2016 and 2017 from the Institute for Fermentation,Osaka,and 2017 Mahidol University Faculty of Dentistry Grant(Grant number:0517.0321/00100)
文摘Objective: To investigate the composition of the salivary microbiome of 50 healthy Thai children. Methods: A total 76 provinces in Thailand are grouped into 5 geographical clusters based on unique economics, foods and lifestyles. Geographical locations and the results of an oral assessment were also considered. Genomic DNA was extracted from stimulated saliva samples. Subsequently, amplicon libraries were prepared by 16 S Metagenomic Sequencing Library Preparation. The amplicons were sequenced using an Illumina Miseq platform followed by bioinformatics and statistical analyses.Results: The correlation between oral hygiene status and caries history varied from r^2=0.887 to r^2=0.999 in the geographical groups, suggesting oral hygiene status a strong association between caries history. Twenty taxonomic groups were found in all subjects and constituted 93.6%-96.5% of the microbiome. Of these, genus Veillonella and Prevotella showed significant differences in their proportions between the geographical groups(P<0.05). Furthermore, the proportion of Veillonella parvula, as well as Rothia aeria and Rothia dentocariosa tended to increase with worse oral hygiene status, which was also related to higher dental caries history.Conclusions: The differences in the salivary microbiome as related to geographic regions suggest that environmental factors, which may include dietary habits, could influence the predominant bacteria found in the mouth of Thai children, especially the genus Veillonella and Prevotella. The ratio of Veillonella parvula, Rothia aeria and Rothia dentocariosa may be indicators of worse oral hygiene status and future caries in this population.
文摘Cryptotanshinone (CT), a major tanshinone of medicinal plant Salvia miltiorrhiza Bunge, demonstrated effective in vitro antibacterial activity against all oral bacteria tested in this experiment. The antibacterial activities of CT against oral bacteria were assessed using the checkerboard and time-kill methods to evaluate the synergistic effects of treatment with ampicillin or gentamicin. The CT was determined against oral pathogenic bacteria with MIC and MBC values ranging from 0.5 to 16 and 1 to 64 μg/mL;for am- picillin from 0.0313 to 16 and 0.125 to 32 μg/mL;for gentamicin from 2 to 256 and 4 to 512 μg/mL respectively. The range of MIC50 and MIC90 were 0.0625 - 8 μg/mL and 1 - 64 μg/mL, respectively. The combination effects of CT with antibiotics were synergistic (FIC index < 0.5) against tested oral bacteria except additive, Streptococcus sobrinus, S. criceti, and Actinobacillus actinomycetemcomitans (FIC index < 0.75 - 1.0). The MBCs were shown reducing ≥4 - 8-fold, indicating a synergistic effect as defined by a FBCI of ≤0.5. Furthermore, a time-kill study showed that the growth of the tested bacteria was completely attenuated after 3 - 6 h of treatment with the 1/2 MIC of CT, regardless of whether it was administered alone or with ampicillin or gentamicin. The results suggest that CT could be employed as a natural antibacterial agent against cariogenic and periodontopathogenic bac- teria.
基金Supported by Faculty of Dentistry,Mahidol University,2008
文摘Objective:To evaluate the level of salivary Mutatis streptococci(MS) after rinsing with xylitol, fluoride,and a combination of xylitol and fluoride solutions,compared with distilled water. Methods:Eighty healthy 8-9 years old subjects with high level of MS(】 10~5 CFU/mL) were equally divided into 4 groups.Subjects rinsed their moutlis for 1 min with 10 mL of 0.05%(w/v) sodium fluoride(NaF),12.5%(w/v) xylitol or 0.05%(w/v) NoF + 12.5%(w/v) xylitol 3 times daily over 10 weeks.Distilled water rinsed group served as a control.Paraffin-stimulated whole saliva samples were collected at baseline,5 weeks,and 10 weeks after rinsing to determine the level of salivary MS by culturing on Mitis Salivarius Bacitracin agar.The statistical significance was calculated by Kruskol Wallis,Mann Whitney U,and Wilcoxon signed-rank tests at a significant level of P【 0.05.Results:Significant reductions in MS count were observed in subjects using 0.05%NaF + 12.5%xylitol over other groups within 5 weeks and after 10 weeks and 12.5%xylitol alone after 10 weeks compared with baseline.Conclusions:The present study provides evidence for the inhibitory effect of xylitol,used in combination with fluoride,delivered in the form of mouthrinse, on salivary MS in the group of schoolchildren.
基金A National Research Foundation of Korea (NRF) grant funded by the government of South Korea (MEST no. 2012R1A2A2A01015470) supported this research
文摘Streptococcus mutans(S. mutans), a major aetiologic agent of dental caries, is involved in systemic diseases, such as bacterial endocarditis, if it enters the bloodstream through temporary bacteraemia. Interleukin(IL)-1β, a proinflammatory cytokine, is related to the host defences against pathogens, and its synthesis, maturation, and secretion are tightly regulated by the activation of the inflammasome, an inflammatory signalling complex. This study examined the signalling mechanism of IL-1β secretion and the inflammasome pathway induced by S. mutans to explain the molecular mechanism through which systemic infection by oral streptococci can occur. After infection of THP-1 cells with S. mutans, the expression of inflammasome components was detected using various methods. S. mutans induced IL-1β secretion via caspase-1 activation, and S. mutans-induced IL-1β secretion required absent in melanoma(AIM2), NLR family pyrin domain-containing 3(NLRP3) and NLR family CARD domain-containing 4(NLRC4)inflammasome activation. In particular, the S. mutans-induced NLRP3 inflammasome was mediated by adenosine triphosphate(ATP) release, potassium depletion and lysosomal damage. Our study provides novel insight into the innate immune response against S. mutans infection.
基金supported by the Korea Medical Device Development Fund grant funded by the Korea government(the Ministry of Science and ICT,the Ministry of Trade,Industry and Energy,the Ministry of Health and Welfare,the Ministry of Food and Drug Safety)(Project Number:KMDF_PR_20200901_0067-01)by the National Research Foundation of Korea(NRF)grant funded by the Korea government(MSIT)(No.2021R1A2C2091260)by faculty research grant of Yonsei University College of Dentistry(6-2021-0037).
文摘Polyalkenoate cement(PAC)is a promising material for regenerative hard tissue therapy.The ionically rich glass component of PAC encourages bioactive interaction via.the release of essential ions.However,PAC bioactivity is restricted owing to(i)structurally inherent cationic network formers and(ii)surface bacterial biofilm formation.These two factors cause a deficiency in ion release,further complicated by secondary infections and premature therapeutic failure.Here,a multivalent zwitterionic network modifier(mZM)is presented for upregulation of ionic exchange and bioactivity enhancement.By introducing a non-zero charged mZM into PACs,an increase in the proportion of non-bridging oxygen occurs.The network modification promotes ion channel formation,causing a multiple-fold increase in ion release and surface deposition of hydroxy-carbonate apatite(ca.74%).Experiments ex vivo and animal models also demonstrate the efficient remineralization ability of the mZM.Furthermore,divalent cationic interaction results in bacterial biofilm reduction(ca.68%)while also influencing a shift in the biofilm species composition,which favors commensal growth.Therefore,PAC modification with mZM offers a promising solution for upregulation of bioactivity,even aiding in customization by targeting site-specific regenerative therapy in future applications.
基金AMED(Grant numbers:JP19fk0108044,JP19fm0208007)Japanese Society for the Promotion of Science(JSPS)KAKENHI(Grant numbers:19H03825,20K18474)。
文摘Invasive infection caused by Streptococcus pyogenes emm89 strains has been increasing in several countries linked to a recently emergent clade of emm89 strains,designated clade 3.In Japan,the features of emm89 S.pyogenes strains,such as clade classification,remains unknown.In this study,we collected emm89 strains isolated from both streptococcal toxic shock syndrome(STSS)(89 STSS isolates)and noninvasive infections(72 non-STSS isolates)in Japan from 2011 to 2019,and conducted wholegenome sequencing and comparative analysis,which resulted in classification of a large majority into clade 3 regardless of disease severity.In addition,invasive disease-associated factors were found among emm89 strains,including mutations of control of virulence sensor,and absence of the hylP1 gene encoding hyaluronidase.These findings provide new insights into genetic features of emm89 strains.
