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1.
Arch Oral Biol ; 109: 104578, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31589997

RESUMO

OBJECTIVE: The aim of this study was to observe the effect of V. parvula on the physiological activity of S. mutans and elucidate the role of V. parvula on dental caries. DESIGN: We constructed dual-species biofilms formed by V. parvula and S. mutans, and measured the pH dynamics, biofilm growth, Extracellular Polysaccharide (EPS) synthesis, and expression of S. mutans EPS synthesis-associated genes affected by V. parvula. RESULTS: pH dynamics were not altered when V. parvula and S. mutans were co-cultured during a 120 -h test period. However, S. mutans cell number and EPS synthesis in dual-species biofilms were found to be significantly higher than in single-species biofilms. Moreover, expression levels of genes encoding glucosyltransferases (gtfs), gtfB and gtfC specifically, were up-regulated when S. mutans was co-cultured with V. parvula. CONCLUSIONS: Our findings indicate that V. parvula is not, as previously thought, protective and associated with caries health. On the contrary, V. parvula might participate in caries development through interactions with S. mutans. This study suggests that V. parvula may have an impact on the pathogenesis of dental caries.


Assuntos
Biofilmes , Streptococcus mutans/fisiologia , Veillonella/fisiologia , Proteínas de Bactérias/genética , Técnicas de Cocultura , Cárie Dentária/microbiologia , Matriz Extracelular de Substâncias Poliméricas , Regulação Bacteriana da Expressão Gênica , Glucosiltransferases/genética
2.
Lett Appl Microbiol ; 70(1): 2-12, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31518435

RESUMO

Dental caries, caused by Streptococcus mutans, is a common infection. Caries vaccine has been under investigation for the last 40 years. Many in vitro and in vivo studies and some human clinical trials have determined many pertinent aspects regarding vaccine development. The virulence determinants of Strep. mutans, such as Ag I/II, responsible for adherence to surfaces, glucosyltransferase, responsible for the production of glucan, and the glucan-binding protein, responsible for the attachment of glucan to surfaces, have been known to elicit an antigen-specific immune response. It is also known that more than one antigen or a functional part of the genome responsible for these virulence determinants provide a better host response compared with the monogenic vaccine or complete genome of a specific antigen. To enhance the host response, the use of adjuvants has been studied and the routes of antigen administration have been investigated. In recent years, some promising vaccines such as pGJA-P/VAX, LT derivative/Pi39-512 , KFD2-rPAc and SBR/GBR-CMV-nirB have been developed and tested in animals. New virulence targets need to be explored. Multicentre collaborative studies and human clinical trials are required and some interest from funders and public health experts should be generated to overcome this hurdle. SIGNIFICANCE AND IMPACT OF THE STUDY: Dental caries is an irreversible, multifactorial opportunistic infection. The treatment is costly, making it a public health problem. Despite many years of promising laboratory research, animal studies and clinical trials, there is no commercially available vaccine today. The research objectives have become more refined from lessons learnt over the years. Multigenic DNA/recombinant vaccines, using the best proved adjuvants with a delivery system for the nasal or sublingual route, should be developed and researched with multicentre collaborative efforts. In addition, new vaccine targets can be identified. To overcome the economic hurdle, funders and public health interest should be stimulated.


Assuntos
Vacinas Bacterianas/imunologia , Cárie Dentária/prevenção & controle , Streptococcus mutans/imunologia , Animais , Vacinas Bacterianas/administração & dosagem , Vacinas Bacterianas/genética , Cárie Dentária/microbiologia , Humanos , Streptococcus mutans/genética , Streptococcus mutans/fisiologia , Vacinas de DNA/administração & dosagem , Vacinas de DNA/genética , Vacinas de DNA/imunologia
3.
BMC Complement Altern Med ; 19(1): 308, 2019 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-31718633

RESUMO

BACKGROUND: Dental caries is a biofilm-diet-dependent worldwide public health problem, and approaches against microorganisms in cariogenic biofilms are necessary. METHODS: The antimicrobial and antibiofilm activities of 12 Casearia sylvestris extracts (0.50 mg/mL) from different Brazilian biomes (Atlantic Forest, Cerrado, Caatinga, Pampa, and Pantanal) and varieties (sylvestris, lingua, and intermediate) were tested against two species found in cariogenic biofilms (Streptococcus mutans and Candida albicans). The extracts effective against S. mutans were used to evaluate the "adhesion strength" of this bacterium to the salivary pellicle and initial glucan matrix and the S. mutans-GtfB activity. Also, the antimicrobial activity against S. mutans of three fractions (methanol, ethyl acetate, and hexane; 0.25 mg/mL) from the extracts was evaluated. RESULTS: Three extracts from the Atlantic Forest variety sylvestris (FLO/SC, GUA/CE, PRE/SP) reduced ≥50% (> 3 logs) S. mutans viable population (p < 0.0001 vs. vehicle), while two extracts from the same biome and variety (PAC/CE, PRE/SP) decreased ≥50% of the viable counts of C. albicans (p < 0.0001 vs. vehicle). For S. mutans biofilms, three extracts (GUA/CE, PAC/CE, PRE/SP) reduced the biomass by ≥91% (p > 0.0001 vs. vehicle) and 100% of the microbial population (p < 0.0001 vs. vehicle). However, for the fungal biofilm, two extracts (PAC/CE, PRE/SP) reduced the viable counts by ≥52% (p < 0.0001 vs. vehicle), but none reduced biomass. The extracts with higher antimicrobial and antibiofilm activities presented higher content of clerodane-type diterpenes and lower content of glycosylated flavonoids than the less active extracts. The extracts had no effect on the removal of cells adhered to the pellicle (p > 0.05 vs. vehicle) while promoted the detachment of a larger number of S. mutans cells from GtfB-glucan matrix (p < 0.0031 vs. vehicle), and FLO/SC, GUA/CE and PRE/SP reduced the quantity of glucans (p < 0.0136 vs. vehicle). Only the ethyl acetate fractions reduced the microbial population of S. mutans (p < 0.0001 vs. vehicle), except for one (PAC/CE). Among the ethyl acetate fractions, three from var. lingua (two from Cerrado, and one from Cerrado/Caatinga) reduced ≥83% of the microbial population. CONCLUSIONS: C. sylvestris extracts from Atlantic Forest var. sylvestris and ethyl acetate fractions from Cerrado and Cerrado/Caatinga var. lingua may be used as a strategy against cariogenic microorganisms.


Assuntos
Anti-Infecciosos/farmacologia , Candida albicans/efeitos dos fármacos , Casearia/química , Cárie Dentária/microbiologia , Extratos Vegetais/farmacologia , Streptococcus mutans/efeitos dos fármacos , Biofilmes/efeitos dos fármacos , Brasil , Candida albicans/fisiologia , Ecossistema , Humanos , Testes de Sensibilidade Microbiana , Streptococcus mutans/fisiologia
4.
Molecules ; 24(17)2019 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-31480443

RESUMO

The accumulation of biofilm by Streptococcus mutans bacteria on hard tooth tissues leads to dental caries, which remains one of the most prevalent oral diseases. Hence, the development of new antibiofilm agents is of critical importance. The current study reports the results from testing the effectiveness of octyl gallate (C8-OG) against: (1) S. mutans biofilm formation on solid surfaces (polystyrene, glass), (2) acidogenicity, (3) and the expression of biofilm-related genes. The amount of biofilm formed by S. mutans bacteria was evaluated using the colorimetric method and optical profilometry. The pH of the biofilm growth medium was measured with microelectrode. A quantitative reverse transcription-polymerase chain reaction (RT-qPCR) was used to assess the expression of genes encoding glucan binding protein B (gbpB), glucosyltransferases B, -C, -D (gtfB, -C, -D), and the F-ATPase ß subunit of the F1 protein (atpD). The results show that C8-OG significantly diminished biofilm formation by exposed S. mutans on solid surfaces and suppressed acidogenicity in a dose-dependent manner, compared to unexposed bacteria (p < 0.05). The C8-OG concentration of 100.24 µM inhibited S. mutans biofilm development on solid surfaces by 100% and prevented a decrease in pH levels by 99%. In addition, the RT-qPCR data demonstrate that the biofilm-producing bacteria treated with C8-OG underwent a significant reduction in gene expression in the case of the four genes under study (gbpB, gtfC, gtfD, and atpD), and there was a slight decrease in expression of the gtfB gene. However, C8-OG treatments did not produce significant expression change compared to the control for the planktonic cells, although there was a significant increase for the atpD gene. Therefore, C8-OG might be a potent antibiofilm and/or anticaries agent for oral formulations that aim to reduce the prevalence of dental caries.


Assuntos
Ácidos/metabolismo , Biofilmes/efeitos dos fármacos , Ácido Gálico/análogos & derivados , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Streptococcus mutans/genética , Streptococcus mutans/fisiologia , Antibacterianos/farmacologia , Biomassa , Ácido Gálico/química , Ácido Gálico/farmacologia , Genes Bacterianos , Vidro/química , Poliestirenos/química , Streptococcus mutans/efeitos dos fármacos , Propriedades de Superfície
5.
Microsc Res Tech ; 82(11): 1869-1877, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31373738

RESUMO

Laser irradiation has been proposed as a preventive method against dental caries since it is capable to inhibit enamel demineralization by reducing carbonate and modifying organic matter, yet it can produce significant morphological changes. The purpose of this study was to evaluate the influence of Er:YAG laser irradiation on superficial roughness of deciduous dental enamel and bacterial adhesion. Fifty-four samples of deciduous enamel were divided into three groups (n = 18 each). G1_control (nonirradiated); G2_100 (7.5 J/cm2 ) and G3_100 (12.7 J/cm2 ) were irradiated with Er:YAG laser at 7.5 and 12.7 J/cm2 , respectively, under water irrigation. Surface roughness was measured before and after irradiation using a profilometer. Afterwards, six samples per group were used to measure bacterial growth by XTT cell viability assay. Adhered bacteria were observed using confocal laser scanning microscopy (CLSM) and a scanning electron microscopy (SEM). Paired t-, one-way analysis of variance (ANOVA), Kruskal-Wallis and pairwise Mann-Whitney U tests were performed to analyze statistical differences (p < .05). Before treatment, samples showed homogenous surface roughness, and after Er:YAG laser irradiation, the surfaces showed a significant increase in roughness values (p < .05). G3_100 (12.7 J/cm2 ) showed the highest amount of Streptococcus mutans adhered (p < .05). The increase in the roughness of the tooth enamel surfaces was proportional to the energy density used; the increase in surface roughness caused by laser irradiation did not augment the adhesion of Streptococcus sanguinis; only the use of the energy density of 12.7 J/cm2 favored significantly the adhesion of S. mutans.


Assuntos
Aderência Bacteriana/efeitos da radiação , Cárie Dentária/prevenção & controle , Esmalte Dentário/efeitos da radiação , Lasers de Estado Sólido/uso terapêutico , Streptococcus mutans/fisiologia , Streptococcus/fisiologia , Aderência Bacteriana/fisiologia , Humanos , Microscopia Eletrônica de Varredura , Streptococcus/crescimento & desenvolvimento , Streptococcus/efeitos da radiação , Streptococcus mutans/crescimento & desenvolvimento , Streptococcus mutans/efeitos da radiação , Propriedades de Superfície/efeitos da radiação
6.
Molecules ; 24(17)2019 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-31466323

RESUMO

Streptococcus mutans is one of the principal pathogens for the development of dental caries. Oral biofilms formed by S. mutans are constructed of insoluble glucan formation induced by the principal enzymes, GTF-I and GTF-SI, in sucrose-containing conditions. However, as another means of biofilm formation, extracellular DNA (eDNA) and membrane vesicles (MVs) are also contributors. To explore the roles of eDNA and MVs for biofilm formation, short and whole size pure DNAs, two types of sub-purified DNAs and MVs were extracted from S. mutans by beads destruction, treatment of proteinase K, and ultracentrifugation of culture supernatant, and applied into the biofilm formation assay using the S. mutans UA159 gtfBC mutant, which lost GTF-I and GTF-SI, on a human saliva-coated 96 well microtiter plate in sucrose-containing conditions. Sub-purified DNAs after cell lysis by beads destruction for total 90 and 180 s showed a complex form of short-size DNA with various proteins and MVs associated with GTF-I and GTF-SI, and induced significantly higher biofilm formation of the S. mutans UA159.gtfBC mutant than no sample (p < 0.05). Short-size pure DNA without proteins induced biofilm formation but whole-size pure DNA did not. Moreover, the complex form of MV associated with GTFs and short-size DNA showed significantly higher biofilm formation of initial colonizers on the human tooth surface such as Streptococcus mitis than no sample (p < 0.05). The short-size DNAs associated with MVs and GTFs are important contributors to the biofilm formation and may be one of additional targets for the prevention of oral biofilm-associated diseases.


Assuntos
Biofilmes/crescimento & desenvolvimento , Vesículas Citoplasmáticas/metabolismo , DNA Bacteriano/genética , Streptococcus mutans/fisiologia , Adulto , Proteínas de Bactérias/genética , Linhagem Celular , Glucosiltransferases/genética , Voluntários Saudáveis , Humanos , Pessoa de Meia-Idade , Mutação , Saliva/microbiologia , Streptococcus mutans/genética
7.
Curr Microbiol ; 76(11): 1238-1246, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31377819

RESUMO

Streptococcus mutans (S. mutans) adheres to the tooth surface, metabolizes carbohydrates, and produces acid products, leading to enamel demineralization-the onset of dental caries. Rapid acidification by S. mutans has been observed in the presence of glucose. However, little is known about the role of small RNAs (sRNAs) in S. mutans in the presence of glucose and their relationship to tooth adherence. The objective of this study was to evaluate the role of sRNAs in S. mutans (18-50 nucleotides) regarding adherence capacity under 1% and 5% glucose concentrations. The pH drop and adherence capacity in the 1% glucose condition were similar to these parameters under conditions of 5% sucrose that were published in our previous study. A total of 2149 candidate sRNA with at least 100 average reads in the 5% and 1% glucose libraries were obtained. Between the two libraries, 581 sRNAs were differentially expressed and 43 sRNAs were verified. However, the expression levels of the predicted target genes gtfC and spaP were similar between the 1% and 5% glucose conditions. The bioinformatic analysis suggested that differentially expressed sRNAs may be involved in several pathways. These findings indicate that sRNAs were induced under these glucose concentrations and a series of sRNAs were specifically induced, respectively. sRNAs that are induced under glucose stress may be involved in regulating adherence of S. mutans.


Assuntos
Aderência Bacteriana , Glucose/análise , RNA Bacteriano/metabolismo , Streptococcus mutans/fisiologia , Cárie Dentária/microbiologia , Regulação Bacteriana da Expressão Gênica , Glucose/metabolismo , Humanos , RNA Bacteriano/genética , Streptococcus mutans/genética , Streptococcus mutans/crescimento & desenvolvimento , Sacarose/metabolismo
8.
Int J Mol Sci ; 20(14)2019 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-31315225

RESUMO

Cariogenic oral biofilms are strongly linked to dental caries around dental sealants. Quaternary ammonium monomers copolymerized with dental resin systems have been increasingly explored for modulation of biofilm growth. Here, we investigated the effect of dimethylaminohexadecyl methacrylate (DMAHDM) on the cariogenic pathogenicity of Streptococcus mutans (S. mutans) biofilms. DMAHDM at 5 mass% was incorporated into a parental formulation containing 20 mass% nanoparticles of amorphous calcium phosphate (NACP). S. mutans biofilms were grown on the formulations, and biofilm inhibition and virulence properties were assessed. The tolerances to acid stress and hydrogen peroxide stress were also evaluated. Our findings suggest that incorporating 5% DMAHDM into 20% NACP-containing sealants (1) imparts a detrimental biological effect on S. mutans by reducing colony-forming unit counts, metabolic activity and exopolysaccharide synthesis; and (2) reduces overall acid production and tolerance to oxygen stress, two major virulence factors of this microorganism. These results provide a perspective on the value of integrating bioactive restorative materials with traditional caries management approaches in clinical practice. Contact-killing strategies via dental materials aiming to prevent or at least reduce high numbers of cariogenic bacteria may be a promising approach to decrease caries in patients at high risk.


Assuntos
Antibacterianos/farmacologia , Biofilmes , Cimentos Dentários/química , Metacrilatos/farmacologia , Streptococcus mutans/efeitos dos fármacos , Ácidos/farmacologia , Antibacterianos/química , Fosfatos de Cálcio/química , Fosfatos de Cálcio/farmacologia , Peróxido de Hidrogênio/farmacologia , Metacrilatos/química , Streptococcus mutans/patogenicidade , Streptococcus mutans/fisiologia
9.
Biomed Res Int ; 2019: 9130806, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31309119

RESUMO

In the article has been presented an analysis of susceptibility of selected dental materials, made in the CAD/CAM technology. The morphology and structural properties of selected dental materials and their composites were determined by using XRPD (X-ray powder diffraction) techniques, as well as the IR (infrared) spectroscopy. Moreover, an adhesion as well as development of biofilm by oral microorganisms has been studied. It has been shown that a degree of the biofilm development on the tested dental materials depended on microorganism genus and species. Streptococcus mutans has demonstrated the best adhesion to the tested materials in comparison with Candida albicans and Lactobacillus rhamnosus. However, the sintered materials such as IPS e.max® and the polished IPS e.max® have showed the best "anti-adhesive properties" in relation to S. mutans and L. rhamnosus that have not formed the biofilm on the polished IPS e.max® sample. Furthermore, S. mutans have not formed the biofilm on both surfaces. On the contrary to S. mutans and L. rhamnosus, C. albicans has demonstrated the adhesive properties in relation to the above-mentioned surfaces. Moreover, in contrast to S. mutans and C. albicans, L. rhamnosus has not formed the biofilm on the polished IPS Empress material.


Assuntos
Biofilmes/crescimento & desenvolvimento , Candida albicans/fisiologia , Desenho Assistido por Computador , Porcelana Dentária/química , Lactobacillus rhamnosus/fisiologia , Teste de Materiais , Streptococcus mutans/fisiologia , Propriedades de Superfície
10.
BMC Res Notes ; 12(1): 383, 2019 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-31287001

RESUMO

OBJECTIVE: Chitosan nanoparticle (nanochitosan) has a broad antimicrobial spectrum against diverse pathogenic microorganisms. However, its effect on dental caries-associated microorganisms, such as Streptococcus mutans and Candida albicans is yet to be explored. These microorganisms are known for causing early childhood caries. Therefore, this study was aimed at investigating nanochitosan inhibition capacity against dual-species biofilms of S. mutans and C. albicans. In this study, nanochitosan antimicrobial activity is reported against mono and dual biofilm species of S. mutans and/or C. albicans at 3 and 18 h incubation time. Nanochitosan inhibition capacity was observed through biofilm mass quantity and cell viability. RESULTS: The present study successfully synthesized nanochitosan with average diameter of approximately 20-30 nm, and also established dual-species biofilms of S. mutans and C. albicans in vitro. With nanochitosan treatment, the cell viability of both microorganisms significantly decreased with the increasing concentration of nanochitosan. There was no significant decrease in biofilm mass both in the dual and single-species biofilms after 3 h of incubation. However, greater inhibition of biofilm was observed at 18 h incubation.


Assuntos
Anti-Infecciosos/farmacologia , Biofilmes/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Quitosana/química , Nanopartículas/química , Streptococcus mutans/efeitos dos fármacos , Anti-Infecciosos/química , Biofilmes/crescimento & desenvolvimento , Candida albicans/fisiologia , Criança , Cárie Dentária/tratamento farmacológico , Cárie Dentária/microbiologia , Placa Dentária/tratamento farmacológico , Placa Dentária/microbiologia , Humanos , Viabilidade Microbiana/efeitos dos fármacos , Microscopia Eletrônica de Transmissão , Nanopartículas/ultraestrutura , Tamanho da Partícula , Streptococcus mutans/fisiologia , Fatores de Tempo
11.
Artigo em Inglês | MEDLINE | ID: mdl-31245303

RESUMO

Streptococci, including the dental pathogen Streptococcus mutans, undergo cell-to-cell signaling that is mediated by small peptides to control critical physiological functions such as adaptation to the environment, control of subpopulation behaviors and regulation of virulence factors. One such model pathway is the regulation of genetic competence, controlled by the ComRS signaling system and the peptide XIP. However, recent research in the characterization of this pathway has uncovered novel operons and peptides that are intertwined into its regulation. These discoveries, such as cell lysis playing a critical role in XIP release and importance of bacterial self-sensing during the signaling process, have caused us to reevaluate previous paradigms and shift our views on the true purpose of these signaling systems. The finding of new peptides such as the ComRS inhibitor XrpA and the peptides of the RcrRPQ operon also suggests there may be more peptides hidden in the genomes of streptococci that could play critical roles in the physiology of these organisms. In this review, we summarize the recent findings in S. mutans regarding the integration of other circuits into the ComRS signaling pathway, the true mode of XIP export, and how the RcrRPQ operon controls competence activation. We also look at how new technologies can be used to re-annotate the genome to find new open reading frames that encode peptide signals. Together, this summary of research will allow us to reconsider how we perceive these systems to behave and lead us to expand our vocabulary of peptide signals within the genus Streptococcus.


Assuntos
Peptídeos/metabolismo , Transdução de Sinais , Streptococcus mutans/genética , Streptococcus mutans/fisiologia , Proteínas de Bactérias/genética , Regulação Bacteriana da Expressão Gênica , Genes Bacterianos/genética , Genoma Bacteriano , Óperon , Peptídeos/genética , Percepção de Quorum
12.
Biofouling ; 35(3): 340-349, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-31066298

RESUMO

This study evaluated the effect of antimicrobial photodynamic therapy (aPDT) on S. mutans using diacetylcurcumin (DAC) and verified DAC toxicity. In vitro, S. mutans biofilms were exposed to curcumin (CUR) and DAC and were light-irradiated. Biofilms were collected, plated and incubated for colony counts. DAC and CUR toxicity assays were conducted with Human Gingival Fibroblast cells (HGF). In vivo, G. mellonella larvae were injected with S. mutans and treated with DAC, CUR and aPDT. The hemolymph was plated and incubated for colony counts. Significant reductions were observed when DAC and CUR alone were used and when aPDT was applied. HGF assays demonstrated no differences in cell viability for most groups. DAC and CUR reduced the S. mutans load in G. mellonella larvae both alone and with aPDT. Systematic toxicity assays on G. mellonella demonstrated no effect of DAC and CUR or aPDT on the survival curve.


Assuntos
Antibacterianos/farmacologia , Curcumina/análogos & derivados , Fármacos Fotossensibilizantes/farmacologia , Streptococcus mutans/efeitos dos fármacos , Biofilmes/efeitos dos fármacos , Curcumina/farmacologia , Humanos , Viabilidade Microbiana/efeitos dos fármacos , Fotoquimioterapia , Streptococcus mutans/fisiologia
13.
J Med Food ; 22(6): 623-630, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31021282

RESUMO

This study was designed to determine whether the ethanol extract of Artemisia princeps could inhibit the cariogenic activity of Streptococcus mutans. The increase in acid production and biofilm formation by S. mutans were evaluated. The expression levels of virulence factor genes were determined by performing the real-time polymerase chain reaction (PCR). The bactericidal effect was tested by confocal laser scanning microscopy. The A. princeps extract was observed to inhibit the growth of S. mutans at concentrations >0.05 mg/mL (P < .05). After using the safranin staining method, we found that the A. princeps extract had an inhibitory effect against biofilm formation at a concentration of >0.05 mg/mL. These experimental results were similar to that observed with the scanning electron microscopy. The results of the confocal microscopy revealed that the A. princeps extract at high concentrations of 0.4-3.2 mg/mL showed a bactericidal effect in a concentration-dependent manner. According to the results of the real-time PCR analysis, it was observed that the A. princeps extract inhibited the expression of virulence factor genes. These results suggest that A. princeps may inhibit the cariogenic activity of S. mutans, and may be useful as an anticariogenic agent.


Assuntos
Antibacterianos/farmacologia , Artemisia/química , Proteínas de Bactérias/genética , Biofilmes/efeitos dos fármacos , Extratos Vegetais/farmacologia , Streptococcus mutans/efeitos dos fármacos , Streptococcus mutans/genética , Fatores de Virulência/genética , Proteínas de Bactérias/metabolismo , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Streptococcus mutans/crescimento & desenvolvimento , Streptococcus mutans/fisiologia , Fatores de Virulência/metabolismo
14.
Dent Med Probl ; 56(1): 33-38, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30875151

RESUMO

BACKGROUND: Dental caries is considered the most common infectious disease in humans worldwide. Cariogenesis is the outcome of a complex interaction between the host's oral flora and diet. The consumption of snacks such as cake, which have the potential to promote dental caries, has increased. OBJECTIVES: The aim of this study was to investigate the effect of including probiotic bacteria (Bacillus coagulans - B. coagulans) in consumed snack cake on the Streptococcus mutans (S. mutans) count and salivary pH. MATERIAL AND METHODS: We conducted a randomized, double-blind, cross-sectional cohort study on 40 healthy volunteers. The subjects were divided into 2 groups. In the 1st group, the subjects consumed probiotic cake as breakfast for 1 week and then, following a 4-week wash-out period, consumed regular cake as breakfast for 1 week. In the other group, the administration of probiotic and regular cake was reversed. For both groups, samples of at least 5 mL of non-stimulated saliva were collected using the spitting technique before and after the 1st and the 6th week. A colony counter was used to determine the number of S. mutans colonies. Salivary pH was measured before eating (8-9 a.m.). RESULTS: We detected no statistically significant difference in the S. mutans count before and after the consumption of probiotic cake, but noted a statistically significant difference in the count before and after the consumption of regular cake. We did not detect a significant difference in salivary pH with respect to the consumption of probiotic and regular cake, although the consumption of both foods caused a drop in salivary pH. CONCLUSIONS: The addition of probiotic bacteria to sweet snack cake caused a minimal increase in the salivary count of S. mutans, a bacterial species with a definite role in cariogenesis, but did not impact salivary pH. Since probiotic cake has a slight impact on the S. mutans count, it is preferred over regular cake as a snack food.


Assuntos
Bacillus coagulans , Probióticos , Saliva , Bacillus coagulans/fisiologia , Carga Bacteriana , Estudos de Coortes , Estudos Transversais , Cárie Dentária/microbiologia , Cárie Dentária/prevenção & controle , Método Duplo-Cego , Humanos , Concentração de Íons de Hidrogênio , Saliva/química , Saliva/microbiologia , Streptococcus mutans/fisiologia
15.
Methods Mol Biol ; 1922: 357-368, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30838590

RESUMO

Caries lesions result from the interaction between dental biofilm and sugars. Since the biofilm is an important component in the etiology of the disease, biofilm models have been developed to study the cariogenicity of dietary sugars, as well as the anticaries effect of substances. Two of such models, termed as "static" or "continuous flow," are described in details here together with their advantages, limitations, and applications.


Assuntos
Biofilmes , Cárie Dentária/microbiologia , Streptococcus mutans/fisiologia , Animais , Técnicas Bacteriológicas/instrumentação , Técnicas Bacteriológicas/métodos , Bovinos , Técnicas de Cultura de Células/instrumentação , Técnicas de Cultura de Células/métodos , Meios de Cultura/química , Meios de Cultura/metabolismo , Cárie Dentária/metabolismo , Esmalte Dentário/microbiologia , Desenho de Equipamento , Humanos , Boca/microbiologia , Açúcares/metabolismo
16.
Methods Mol Biol ; 1922: 369-377, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30838591

RESUMO

Due to the high failure rates of traditional dental restorations, there is an ongoing effort to develop modified and new restorative biomaterials in dentistry. Being the most commonly used restorative material, most of these efforts primarily aim to improve dental composite. Generally, the main objective of such modifications is to enhance the restorative physical and antimicrobial properties in order to limit micro-leakage and inhibit bacterial biofilm cultivation. Herein, we describe the process of designing a simple in vitro model to assess the physical and antimicrobial properties of novel restorative materials in addition to evaluating their effect on the fragile balance between enamel de- and remineralization.


Assuntos
Anti-Infecciosos/farmacologia , Cárie Dentária/microbiologia , Cárie Dentária/terapia , Materiais Dentários/farmacologia , Streptococcus mutans/efeitos dos fármacos , Animais , Biofilmes/efeitos dos fármacos , Bovinos , Resinas Compostas/farmacologia , Esmalte Dentário/microbiologia , Incisivo/microbiologia , Microscopia Confocal/métodos , Streptococcus mutans/fisiologia
17.
Methods Mol Biol ; 1922: 393-403, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30838593

RESUMO

Dental caries is an infectious oral disease caused primarily by complex interactions of cariogenic oral flora (biofilm) with dietary carbohydrates on the tooth surface over time. Streptococcus mutans and Streptococcus sobrinus (S. mutans and S. sobrinus) are the most prevalent cariogenic species within the oral biofilm and considered the main etiological agents of caries. Pulp exposure and infection can be caused by trauma, carious lesion, and mechanical reasons. Pulp response to these exposures depends on the state of the pulp as well as the potential bacterial contamination of pulp tissue. Herein, we describe the process of using two in vivo rodent models to study the progression of dental caries and pulp disease: a nutritional microbial model and a pulp disease induction model. The progression of the carious lesion and pulpal infections in both models was assessed by micro-CT imaging and histomorphometric analysis. Moreover, the pulp disease induction models can be used to compare and assess the antibacterial and reparative properties of the different pulp capping materials.


Assuntos
Cárie Dentária/microbiologia , Cárie Dentária/patologia , Streptococcus mutans/fisiologia , Streptococcus sobrinus/fisiologia , Animais , Biofilmes , Polpa Dentária/microbiologia , Polpa Dentária/patologia , Modelos Animais de Doenças , Progressão da Doença , Ratos Sprague-Dawley , Microtomografia por Raio-X/métodos
18.
ACS Appl Mater Interfaces ; 11(8): 7686-7694, 2019 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-30768237

RESUMO

Quorum sensing (QS) inhibitor-based therapy is an attractive strategy to inhibit bacterial biofilm formation without excessive induction of antibiotic resistance. Thus, we designed Ca2+-binding poly(lactide- co-glycolide) (PLGA) microparticles that can maintain a sufficient concentration of QS inhibitors around hydroxyapatite (HA) surfaces in order to prevent biofilm formation on HA-based dental or bone tissues or implants and, therefore, subsequent pathogenesis. Poly(butyl methacrylate- co-methacryloyloxyethyl phosphate) (PBMP) contains both Ca2+-binding phosphomonoester groups and PLGA-interacting butyl groups. The PBMP-coated PLGA (PLGA/PBMP) microparticles exhibited superior adhesion to HA surfaces without altering the sustained release properties of uncoated PLGA microparticles. PLGA/PBMP microparticle-encapsulating furanone C-30, a representative QS inhibitor, effectively inhibited the growth of Streptococcus mutans and its ability to form biofilms on HA surface for prolonged periods of up to 100 h, which was much longer than either furanone C-30 in its free form or when encapsulated in noncoated PLGA microparticles.


Assuntos
Biofilmes/efeitos dos fármacos , Cálcio/química , Durapatita/química , Furanos/farmacologia , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Polímeros/química , Percepção de Quorum/efeitos dos fármacos , Animais , Cálcio/metabolismo , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Portadores de Fármacos/química , Furanos/química , Metacrilatos/química , Camundongos , Polímeros/síntese química , Streptococcus mutans/fisiologia , Propriedades de Superfície
19.
Am J Orthod Dentofacial Orthop ; 155(2): 243-253, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30712696

RESUMO

INTRODUCTION: This study evaluated the efficacy of photodynamic inactivation (PDI) with hematoporphyrin IX (H) and modified hematoporphyrin IX (MH) at 10 µmol/L, using a blue light-emitting diode (LED), fluence of 75 J/cm,2 over planktonic cultures and biofilm of Streptococcus mutans (UA 159). METHODS: Suspensions containing 107 cells/mL were tested under different experimental conditions: a) H and LED (H+L+), b) MH and LED (MH+L+), c) only LED (P-L+), d) only H (H+L-), e) only MH (MH+L-), and f) control group, no LED or photosensitizer treatment (P-L-). The study also evaluated the effect of PDI on S mutans biofilm on metallic or ceramic brackets bonded on specimens of human teeth. The strains were seeded onto Mitis salivarius-bacitracin-sacarose agar to determine the number of colony-forming units. RESULTS: H and MH under LED irradiation were effective on planktonic cultures (P <0.0001). H and MH (H+L+ and MH+L+) caused a reduction of 3.80 and 6.78 log10 CFU/mL. PDI with the use of H or MH and LED exerted a strong antimicrobial effect over S mutans showing 54% and 100% reduction, respectively. PDI on S mutans biofilm on metallic and ceramic brackets with the use of H was not effective (P = 0.0162, P = 0.1669), however, MH caused a significant reduction of 44% and 53% of the cell count on metallic and ceramic brackets, respectively (P = 0.0020, P = 0.004). CONCLUSIONS: In vitro planktonic cultures with the use of H or MH and LED exerted significant antimicrobial activity. No effect was observed on S mutans biofilm on either bracket type with the use of H, MH showed better results, suggesting a promising use against dental caries and white spot lesions.


Assuntos
Biofilmes/efeitos dos fármacos , Biofilmes/efeitos da radiação , Cárie Dentária/etiologia , Cárie Dentária/prevenção & controle , Hematoporfirinas/farmacologia , Ortodontia Corretiva/efeitos adversos , Fotoquimioterapia , Fármacos Fotossensibilizantes/farmacologia , Plâncton/efeitos dos fármacos , Plâncton/efeitos da radiação , Streptococcus mutans/efeitos dos fármacos , Streptococcus mutans/efeitos da radiação , Humanos , Técnicas In Vitro , Streptococcus mutans/fisiologia
20.
Microbiol Spectr ; 7(1)2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30657107

RESUMO

As a major etiological agent of human dental caries, Streptococcus mutans resides primarily in biofilms that form on the tooth surfaces, also known as dental plaque. In addition to caries, S. mutans is responsible for cases of infective endocarditis with a subset of strains being indirectly implicated with the onset of additional extraoral pathologies. During the past 4 decades, functional studies of S. mutans have focused on understanding the molecular mechanisms the organism employs to form robust biofilms on tooth surfaces, to rapidly metabolize a wide variety of carbohydrates obtained from the host diet, and to survive numerous (and frequent) environmental challenges encountered in oral biofilms. In these areas of research, S. mutans has served as a model organism for ground-breaking new discoveries that have, at times, challenged long-standing dogmas based on bacterial paradigms such as Escherichia coli and Bacillus subtilis. In addition to sections dedicated to carbohydrate metabolism, biofilm formation, and stress responses, this article discusses newer developments in S. mutans biology research, namely, how S. mutans interspecies and cross-kingdom interactions dictate the development and pathogenic potential of oral biofilms and how next-generation sequencing technologies have led to a much better understanding of the physiology and diversity of S. mutans as a species.


Assuntos
Biofilmes/crescimento & desenvolvimento , Cárie Dentária/microbiologia , Placa Dentária/microbiologia , Streptococcus mutans/fisiologia , Streptococcus mutans/patogenicidade , Metabolismo dos Carboidratos/fisiologia , Cárie Dentária/patologia , Placa Dentária/patologia , Humanos , Transdução de Sinais/fisiologia , Streptococcus mutans/metabolismo
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