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1.
PLoS One ; 15(10): e0239775, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33036019

RESUMO

In this study, we evaluated the antibacterial activities of the essential oils (EOs) of Thymus serrulatus and Thymus schimperi collected from Ofla (Ofl), Alamata (Ala), Yilmana Densa (Yil), Tarmaer (Tar), Butajira (Buta), and Bale (Bal) in Ethiopia against cariogenic bacteria (Streptococcus mutans and Lactobacillus) isolated from human teeth. Inhibition zones (IZs), minimum inhibitory concentrations (MICs), and minimum bactericidal concentrations (MBCs) were measures of the antibacterial activity. Significant bacterial inhibitions resulted in a dose-and EO-dependent manner. At 128 µl/mL, IZs against S. mutans were 37.33 mm (Tar), 36.00 mm (Bal), 33.67 mm (Yil), 33.33 mm (Ofl), 30.00 (Ala), and 29.67 mm (Buta) and IZs against Lactobacillus were 31.00 mm (Tar), 30.67 mm (Yil), 27.67 (Bal), 27.00 (Buta), 26.67 (Ofl), and 21.33 (Ala). The respective inhibition zones due to 3% DMSO (negative control) and 3% H2O2 (positive control) were 0.00 mm/30.00 mm against S. mutans and 0.00 mm/29.00 mm against Lactobacillus. At 128 µl/mL dose, all the EOs resulted in significantly higher inhibition zones than that of 3% H2O2 against S. mutans and Lactobacillus.


Assuntos
Antibacterianos/farmacologia , Cárie Dentária/tratamento farmacológico , Cárie Dentária/microbiologia , Lactobacillus/efeitos dos fármacos , Óleos Voláteis/farmacologia , Streptococcus mutans/efeitos dos fármacos , Thymus (Planta)/química , Etiópia , Humanos , Testes de Sensibilidade Microbiana/métodos
2.
AAPS PharmSciTech ; 21(6): 227, 2020 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-32767025

RESUMO

Streptococcus mutans (S. mutans) is the principal etiologic agent in the occurrence of human dental caries and the formation of biofilms on the surface of teeth. Tea tree oil (TTO) has been demonstrated to exhibit a wide range of pharmacological actions that can effectively inhibit the activity of bacteria. In this context, we evaluated the in vitro antimicrobial effects of TTO on S. mutans both during planktonic growth and in biofilms compared with 0.2% CHX. We determined the minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) using the microdilution method, the bacteriostatic rate using an MTT assay, and the antimicrobial time using a time-kill assay. Then, we explored the effects of TTO on acid production and cell integrity. Furthermore, the effects of TTO on the biomass and bacterial activity of S. mutans biofilms were studied. Finally, scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM) were used to investigate the structure and activity of biofilms. The MIC and MBC values were 0.125% and 0.25%, and the bacterial inhibition rate was concentration dependent. TTO can effectively inhibit bacterial acid production and destroy the integrity of the cell membrane. Electron micrographs revealed a reduction in bacterial aggregation, inhibited biofilm formation, and reduced biofilm thickness. The effect of TTO was the same as that of 0.2% CHX at a specific concentration. In summary, we suggest that TTO is a potential anticariogenic agent that can be used against S. mutans.


Assuntos
Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Óleo de Melaleuca/farmacologia , Cárie Dentária/microbiologia , Humanos , Técnicas In Vitro , Testes de Sensibilidade Microbiana , Microscopia Confocal , Microscopia Eletrônica de Varredura , Streptococcus mutans/efeitos dos fármacos
3.
PLoS Pathog ; 16(7): e1008774, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32716974

RESUMO

S-glutathionylation is an important post-translational modification (PTM) process that targets protein cysteine thiols by the addition of glutathione (GSH). This modification can prevent proteolysis caused by the excessive oxidation of protein cysteine residues under oxidative or nitrosative stress conditions. Recent studies have suggested that protein S-glutathionylation plays an essential role in the control of cell-signaling pathways by affecting the protein function in bacteria and even humans. In this study, we investigated the effects of S-glutathionylation on physiological regulation within Streptococcus mutans, the primary etiological agent of human dental caries. To determine the S-glutathionylated proteins in bacteria, the Cys reactive isobaric reagent iodoacetyl Tandem Mass Tag (iodoTMT) was used to label the S-glutathionylated Cys site, and an anti-TMT antibody-conjugated resin was used to enrich the modified peptides. Proteome profiling identified a total of 357 glutathionylated cysteine residues on 239 proteins. Functional enrichment analysis indicated that these S-glutathionylated proteins were involved in diverse important biological processes, such as pyruvate metabolism and glycolysis. Furthermore, we studied a thioredoxin-like protein (Tlp) to explore the effect of S-glutathionylation on interspecies competition between oral streptococcal biofilms. Through site mutagenesis, it was proved that glutathionylation on Cys41 residue of Tlp is crucial to protect S. mutans from oxidative stress and compete with S. sanguinis and S. gordonii. An addition rat caries model showed that the loss of S-glutathionylation attenuated the cariogenicity of S. mutans. Taken together, our study provides an insight into the S-glutathionylation of bacterial proteins and the regulation of oxidative stress resistance and interspecies competition.


Assuntos
Cárie Dentária/microbiologia , Interações Microbianas/fisiologia , Streptococcus mutans/metabolismo , Streptococcus mutans/patogenicidade , Tiorredoxinas/metabolismo , Animais , Proteínas de Bactérias/metabolismo , Biofilmes , Cárie Dentária/metabolismo , Humanos , Processamento de Proteína Pós-Traducional , Proteoma/metabolismo , Ratos
4.
Niger J Clin Pract ; 23(6): 783-791, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32525112

RESUMO

Background: Microorganisms in the mouth are protected from negative environmental conditions by forming biofilms; however, the use of anti-plaque agents in children is not preferred due to toxic side effects. Green tea has been reported to have anti-microbial and anti-dental caries properties. Aims: The aim of this study was to assess the ability of green tea extract to prevent the formation of biofilm on the teeth of children using space maintainers. Methods: Bacteria were isolated from samples obtained from children aged between 8 and 10 years. The micro-titer plate method and Congo red agar were used to assay biofilm formation. Green tea leaves were obtained from Rize, Turkey. Methanol, hexane and distilled water were used for preparing the extracts. The effects of green tea extract and chlorhexidine on biofilm formation were examined using scanning electron microscopy. Results: Presence of S. mutans 3,3, S. anginosus 2.1.b, S. dysgalactie 6.1.4.1, and E. faecium 10.2. was measured in the biofilm samples. The extracts showed a bacteriostatic effect on the test bacteria, and among the green tea extracts, the methanol extract was found to exhibit the highest efficacy against biofilm formation by S. mutans 3.3. Conclusion: Green tea extract showed good efficacy in controlling bacterial growth, and is recommended as a better-tasting alternative for daily oral hygiene due to a lack of known side effects.


Assuntos
Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Clorexidina/farmacologia , Cárie Dentária/microbiologia , Braquetes Ortodônticos/microbiologia , Extratos Vegetais/farmacologia , Infecções Estreptocócicas/tratamento farmacológico , Streptococcus mutans/efeitos dos fármacos , Chá/química , Antioxidantes/farmacologia , Carga Bacteriana/efeitos dos fármacos , Criança , Cárie Dentária/tratamento farmacológico , Humanos , Metanol , Testes de Sensibilidade Microbiana , Boca , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Solventes/química , Streptococcus mutans/isolamento & purificação , Streptococcus mutans/fisiologia , Turquia
5.
BMC Oral Health ; 20(1): 160, 2020 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-32493272

RESUMO

BACKGROUND: The use of silver-formulation as microbicide to arrest dentinal caries is gaining popularity. The primary objective of the present appraisal was to systematically review the clinical (in vivo) applications and antimicrobial potential of silver-containing formulations in arresting dentinal caries. Our secondary aim was to sum up the available in vitro applications of silver-containing formulations against cariogenic microbes isolated from dentine lesions. METHODS: Ovid MEDLINE, EBSCO host, Web of Science, and Cochrane Library databases was searched between January 2009-May 2019. RESULTS: In vivo: We observed conflicting evidence of antimicrobial efficacy of SDF on a diverse array of microbial taxa present in carious dentine of primary and permanent teeth. Moreover, there is insufficient evidence on the application of AgNP-fluoride as an effective microbicidal against cariogens of dentine lesions. In vitro: We found a good evidence of microbicidal efficacy of silver diamine fluoride (SDF) on selective cariogenic microbes in human dentine model. Additionally, a good evidence was noted of in vitro application of silver nanoparticles (AgNPs) as a useful microbicidal against S. mutans adhesion, growth and subsequent biofilm formation in human dentine models. CONCLUSIONS: Taken together, in vitro evidence indicates the promising antimicrobial potential of silver-based formulations (SDF and nanosilver) against the predominant cariogenic flora, particularly from dentine lesions. Post-treatment clinical data of either the bactericidal and bacteriostatic effects of SDF or nanosilver are sparse. Furthermore, the current understanding of the specific size, concentration, antimicrobial mechanisms, and toxicological aspects of nano-silver compounds is inadequate to draw firm conclusions on their clinical utility.


Assuntos
Anti-Infecciosos/farmacologia , Cariostáticos/farmacologia , Cárie Dentária/microbiologia , Cárie Dentária/prevenção & controle , Compostos de Amônio Quaternário/farmacologia , Streptococcus mutans/efeitos dos fármacos , Biofilmes/efeitos dos fármacos , Cárie Dentária/tratamento farmacológico , Fluoretos Tópicos , Humanos , Nanopartículas Metálicas , Viabilidade Microbiana/efeitos dos fármacos , Prata , Compostos de Prata , Resultado do Tratamento
6.
Proc Natl Acad Sci U S A ; 117(22): 12375-12386, 2020 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-32424080

RESUMO

Tooth decay (dental caries) is a widespread human disease caused by microbial biofilms. Streptococcus mutans, a biofilm-former, has been consistently associated with severe childhood caries; however, how this bacterium is spatially organized with other microorganisms in the oral cavity to promote disease remains unknown. Using intact biofilms formed on teeth of toddlers affected by caries, we discovered a unique 3D rotund-shaped architecture composed of multiple species precisely arranged in a corona-like structure with an inner core of S. mutans encompassed by outer layers of other bacteria. This architecture creates localized regions of acidic pH and acute enamel demineralization (caries) in a mixed-species biofilm model on human teeth, suggesting this highly ordered community as the causative agent. Notably, the construction of this architecture was found to be an active process initiated by production of an extracellular scaffold by S. mutans that assembles the corona cell arrangement, encapsulating the pathogen core. In addition, this spatial patterning creates a protective barrier against antimicrobials while increasing bacterial acid fitness associated with the disease-causing state. Our data reveal a precise biogeography in a polymicrobial community associated with human caries that can modulate the pathogen positioning and virulence potential in situ, indicating that micron-scale spatial structure of the microbiome may mediate the function and outcome of host-pathogen interactions.


Assuntos
Cárie Dentária/microbiologia , Microbiota , Boca/microbiologia , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Fenômenos Fisiológicos Bacterianos , Biofilmes , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Streptococcus mutans/genética , Streptococcus mutans/isolamento & purificação , Streptococcus mutans/fisiologia
7.
Int J Nanomedicine ; 15: 3181-3191, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32440117

RESUMO

Objective: The aim of this concise review is to summarize the use of silver nanomaterials for caries prevention. Methods: Two researchers independently performed a literature search of publications in English using Embase, Medline, PubMed, and Scopus databases. The keywords used were (silver nanoparticles OR AgNPs OR nano silver OR nano-silver) AND (caries OR tooth decay OR remineralisation OR remineralization). They screened the title and abstract to identify potentially eligible publications. They then retrieved the full texts of the identified publications to select original research reporting silver nanomaterials for caries prevention. Results: The search identified 376 publications, and 66 articles were included in this study. The silver nanomaterials studied were categorized as resin with silver nanoparticles (n=31), silver nanoparticles (n=21), glass ionomer cement with silver nanoparticles (n=7), and nano silver fluoride (n=7). Most (59/66, 89%) studies investigated the antibacterial properties, and they all found that silver nanomaterials inhibited the adhesion and growth of cariogenic bacteria, mainly Streptococcus mutans. Although silver nanomaterials were used as anti-caries agents, only 11 (11/66, 17%) studies reported the effects of nanomaterials on the mineral content of teeth. Eight of them are laboratory studies, and they found that silver nanomaterials prevented the demineralization of enamel and dentin under an acid or cariogenic biofilm challenge. The remaining three are clinical trials that reported that silver nanomaterials prevented and arrested caries in children. Conclusion: Silver nanoparticles have been used alone or with resin, glass ionomer, or fluoride for caries prevention. Silver nanomaterials inhibit the adhesion and growth of cariogenic bacteria. They also impede the demineralization of enamel and dentin.


Assuntos
Cárie Dentária/tratamento farmacológico , Cárie Dentária/prevenção & controle , Nanoestruturas/uso terapêutico , Prata/uso terapêutico , Cariostáticos/farmacologia , Cariostáticos/uso terapêutico , Cárie Dentária/microbiologia , Esmalte Dentário/efeitos dos fármacos , Dentina/efeitos dos fármacos , Humanos , Prata/farmacologia
8.
Int J Nanomedicine ; 15: 3207-3215, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32440119

RESUMO

Objectives: The first objective of this study was to prepare sodium fluoride (NaF) solution with various concentrations of polyethylene glycol-coated silver nanoparticles (PEG-AgNPs). The second objective was to study the antibacterial activity against Streptococcus mutans and the tooth-staining effect of the solution. Methods: PEG-AgNPs were prepared via the one-step chemical reduction of silver acetate with thiolated polyethylene glycol. The PEG-AgNPs were characterized with ultraviolet-visible spectrometry and transmission electron microscopy. The half maximal inhibitory concentration (IC50) for the PEG-AgNPs against Streptococcus mutans and human gingival fibroblasts (HGF-1) were determined. The staining effect on dentin and enamel for the 2.5% NaF solutions with PEG-AgNPs at 12,800, 6400, 1600, and 400 ppm was investigated using digital spectrophotometry. The IC50 of the fluoridated silver nanoparticles against Streptococcus mutans were measured. Results: The PEG-AgNPs have an average diameter of 2.56±0.43 nm and showed excellent stability at high ionic strength (2.5% NaF) for 18 months. The IC50 of PEG-AgNPs against Streptococcus mutans was found to be 21.16±1.08 ppm silver, which was half of IC50 against HGF-1 cells (42.36±1.12 ppm), providing a working range to kill bacteria with no harm to human cells. The formulations with different concentrations of PEG-AgNPs showed no significant staining of teeth. Combining PEG-AgNPs with NaF significantly expanded the therapeutic window against Streptococcus mutans by reducing its IC50. Conclusion: A biocompatible solution of NaF with PEG-AgNPs was developed. Because it has antibacterial activity against Streptococcus mutans and no tooth-staining effect, it can be used as an anti-caries agent.


Assuntos
Cárie Dentária/tratamento farmacológico , Fluoretos/síntese química , Fluoretos/uso terapêutico , Nanopartículas Metálicas/química , Prata/uso terapêutico , Coloração e Rotulagem , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Cariostáticos/farmacologia , Cariostáticos/uso terapêutico , Cárie Dentária/microbiologia , Gengiva/efeitos dos fármacos , Humanos , Nanopartículas Metálicas/ultraestrutura , Testes de Sensibilidade Microbiana , Polietilenoglicóis/química , Prata/farmacologia , Espectrofotometria Ultravioleta , Streptococcus mutans/efeitos dos fármacos
9.
Int J Food Microbiol ; 325: 108645, 2020 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-32353648

RESUMO

In this study, we focus on the antimicrobial properties of tempeh, a soybean fermented food, against oral bacteria. Tempeh showed antimicrobial activity against dental caries pathogenic bacterium Streptococcus mutans at a final concentration of 1 mg/mL. An antimicrobial substance contained in tempeh was present in the 100 kDa or greater fraction generated by ultrafiltration, but it was found not to be proteinaceous by native-PAGE, SDS-PAGE and protein degradation tests. Next, when the fraction was purified with an ODS column, the 80% and 100% methanol eluates showed antimicrobial activity against S. mutans. The 100% methanol eluate was further subjected to a 2nd column purification, and isolation of the target was confirmed by HPLC. When the isolated material was analyzed by ESI-MS, the m/z was 279.234. Further analysis by Raman spectroscopy revealed a peak similar to linoleic acid. This substance also possessed antimicrobial properties equivalent to linoleic acid.


Assuntos
Anti-Infecciosos/isolamento & purificação , Extratos Vegetais/farmacologia , Rhizopus/metabolismo , Soja/metabolismo , Streptococcus mutans/efeitos dos fármacos , Anti-Infecciosos/análise , Cárie Dentária/microbiologia , Cárie Dentária/prevenção & controle , Fermentação , Alimentos e Bebidas Fermentados/análise , Alimentos de Soja/análise , Soja/microbiologia
10.
Acta Vet Scand ; 62(1): 21, 2020 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-32446309

RESUMO

BACKGROUND: The role of saliva composition and dietary sugar in development of infundibular caries in equine cheek teeth is not fully understood. This study analysed electrolyte and urea concentrations in saliva in relation to different forage and measured pH changes after sucrose application in vivo in sound and carious cheek teeth. RESULTS: Forage type had no effect on the equine saliva electrolyte concentrations, which varied considerably both intra- and inter-individually. Chewing resulted in increased values for all electrolytes except bicarbonate. Compared with stimulated human saliva, horse saliva after mastication, contained higher amounts of potassium, calcium and bicarbonate, and less phosphate. The in vivo pH measurements showed a lower resting pH and a more pronounced pH drop after sucrose application in carious teeth compared to sound teeth. CONCLUSIONS: No large differences were found between the composition of equine saliva and human saliva. A more pronounced acidogenicity was found for the carious than sound teeth. Thus, the caries process in equine cheek teeth seems to follow the same pattern as in human teeth, caused by acid production by oral microorganisms after sugar consumption.


Assuntos
Biofilmes/efeitos dos fármacos , Cárie Dentária/microbiologia , Cavalos/fisiologia , Mastigação/fisiologia , Saliva/química , Sacarose/farmacologia , Dente/microbiologia , Animais , Concentração de Íons de Hidrogênio , Microbiota/efeitos dos fármacos
11.
Georgian Med News ; (299): 131-137, 2020 Feb.
Artigo em Russo | MEDLINE | ID: mdl-32242860

RESUMO

The article indicates that the oral cavity is one of the complex and stable biotopes, very favorable for the growth and maintenance of the vital activity of microorganisms. However, the biocenoses of all human biotopes are inextricably linked and a change in one of them causes changes in the others. These changes can also lead to negative consequences for the macroorganism. It is known that such common human diseases as tooth decay and inflammatory periodontal diseases are caused by representatives of oral microbiocenosis. These pathologies have their own characteristics and are the result of intermicrobial and organismic relationships. The questions of intermicrobial relations were dealt with by the American ecologist Eugene Odum, who classified biotic relationships by the nature of their influence on interacting species, as well as the Italian mathematician Vito Volterra, considered the founder of the modern mathematical theory of populations. Ukrainian Medical Stomatological Academy employees pay great attention to the study of oral microbiocenosis in normal conditions and in various pathologies. We carried out the calculations of microflora studied in one of these researches according to the V. Volterra formulas and using the modified classification of Yu. Odum. They showed the possibility of determining the type of relationship between associates of the oral biotope. This position may be useful when planning hygienic and therapeutic procedures performed in the oral cavity.


Assuntos
Cárie Dentária/microbiologia , Mucosa Bucal/microbiologia , Boca/microbiologia , Doenças Periodontais/microbiologia , Humanos
12.
Biofouling ; 36(3): 245-255, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32326753

RESUMO

Dental plaque is a biofilm composed of a complex oral microbial community. The accumulation of plaque in the pit and fissures of dental elements often leads to the development of tooth decay (dental caries). Here, potent anti-biofilm materials were developed by incorporating zinc methacrylates or di-n-butyl-dimethacrylate-tin into the light-curable sealant and their physical, mechanical, and biological properties were evaluated. The data revealed that 5% di-n-butyl-dimethacrylate-tin (SnM 5%) incorporated sealant showed strong anti-biofilm efficacy against various single-species (Streptococcus mutans or Streptococcus oralis or Candida albicans) and S. mutans-C. albicans cross-kingdom dual-species biofilms without either impairing the mechanical properties of the sealant or causing cytotoxicities against mouse fibroblasts. The findings indicate that the incorporation of SnM 5% in the experimental pit and fissure self-adhesive sealant may have the potential to be part of current chemotherapeutic strategies to prevent the formation of cariogenic oral biofilms that cause dental caries.


Assuntos
Adesivos/farmacologia , Biofilmes/efeitos dos fármacos , Cárie Dentária/prevenção & controle , Selantes de Fossas e Fissuras/farmacologia , Zinco/química , Adesivos/química , Animais , Biofilmes/crescimento & desenvolvimento , Candida albicans/efeitos dos fármacos , Candida albicans/crescimento & desenvolvimento , Cárie Dentária/microbiologia , Humanos , Metacrilatos/química , Camundongos , Microbiota/efeitos dos fármacos , Selantes de Fossas e Fissuras/química , Streptococcus mutans/efeitos dos fármacos , Streptococcus mutans/crescimento & desenvolvimento , Streptococcus oralis/efeitos dos fármacos , Streptococcus oralis/crescimento & desenvolvimento
13.
Biocontrol Sci ; 25(1): 41-44, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32173666

RESUMO

Chlorhexidine digluconate inhibits oral bacteria and the formation of dental plaque. Protamine sulfate, a polycationic protein, exerts antibacterial activity by altering the cell wall of bacteria. Extracts of Laminaria japonica and Rosmarinus officinalis display antimicrobial effects against oral pathogens. The purpose of this study was to investigate the synergistic effect of chlorhexidine digluconate and protamine sulfate on the inhibitory activity of L. japonica and R. officinalis extracts against Streptococcus mutans, a major etiological agent for dental caries. Minimal inhibitory concentrations (MICs) of chlorhexidine digluconate, protamine sulfate, and L. japonica and R. officinalis extracts were determined by broth dilution method. Synergistic effect of chlorhexidine digluconate or protamine sulfate and extracts of L. japonica or R. officinalis was determined by fractional inhibitory concentration index (FIC). FIC demonstrated the synergistic effects of the different combinations of antibacterial agents. In this study, the use of sub-MIC of chlorhexidine digluconate or protamine sulfate with sub-MIC of L. japonica and R. officinalis extracts resulted in synergistic inhibitory effects of these antibacterial agents except for chlorhexidine digluconate and L. japonica combination.


Assuntos
Antibacterianos/farmacologia , Clorexidina/análogos & derivados , Laminaria/química , Extratos Vegetais/farmacologia , Protaminas/farmacologia , Rosmarinus/química , Streptococcus mutans/efeitos dos fármacos , Clorexidina/farmacologia , Cárie Dentária/microbiologia , Sinergismo Farmacológico , Humanos , Testes de Sensibilidade Microbiana
14.
Am J Orthod Dentofacial Orthop ; 157(3): 385-391, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32115117

RESUMO

INTRODUCTION: Orthodontic patients are at an increased risk for developing caries. Dental caries is a biofilm-mediated disease, with mutans streptococci (MS) as the primary etiologic bacterial group. It has been suggested that persister cells (PCs), a subset of cells within the biofilm, contribute to the chronic infectious nature of dental caries. PC formation can be induced by environmental stressors such as orthodontic treatment. The aim of this study was to quantify MS, aerobic and facultative anaerobe bacterial PC proportions from plaque samples during the initial stage of orthodontic treatment. This study is the first to analyze the role of PCs in a population of patients highly susceptible to caries, that is, patients undergoing orthodontic treatment. METHODS: Plaque samples were collected from 17 participants (11 males and 6 females; age range: 11-18 years) before and 1 month after insertion of fixed orthodontic appliances. Percentages of MS and PCs were determined with selective media and a classical persister microbial assay, respectively. RESULTS: There was a statistically significant decrease in %MS (P = 0.039) but no statistically significant difference in %PCs (P = 0.939) after 1 month of orthodontic appliance placement. CONCLUSION: Our study illustrated the technical feasibility of analysis of PCs in plaque samples of patients during orthodontic treatment and revealed that PC formation during orthodontic treatment is highly variable across individuals.


Assuntos
Cárie Dentária , Placa Dentária , Aparelhos Ortodônticos Fixos , Streptococcus mutans , Adolescente , Criança , Cárie Dentária/microbiologia , Feminino , Humanos , Masculino , Aparelhos Ortodônticos , Aparelhos Ortodônticos Fixos/microbiologia , Saliva , Streptococcus mutans/isolamento & purificação
15.
Sci Rep ; 10(1): 2133, 2020 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-32034250

RESUMO

Oral microbiome dysbiosis has been associated with various local and systemic human diseases such as dental caries, periodontal disease, obesity, and cardiovascular disease. Bacterial composition may be affected by age, oral health, diet, and geography, although information about the natural variation found in the general public is still lacking. In this study, citizen-scientists used a crowdsourcing model to obtain oral bacterial composition data from guests at the Denver Museum of Nature & Science to determine if previously suspected oral microbiome associations with an individual's demographics, lifestyle, and/or genetics are robust and generalizable enough to be detected within a general population. Consistent with past research, we found bacterial composition to be more diverse in youth microbiomes when compared to adults. Adult oral microbiomes were predominantly impacted by oral health habits, while youth microbiomes were impacted by biological sex and weight status. The oral pathogen Treponema was detected more commonly in adults without recent dentist visits and in obese youth. Additionally, oral microbiomes from participants of the same family were more similar to each other than to oral microbiomes from non-related individuals. These results suggest that previously reported oral microbiome associations are observable in a human population containing the natural variation commonly found in the general public. Furthermore, these results support the use of crowdsourced data as a valid methodology to obtain community-based microbiome data.


Assuntos
Microbiota/fisiologia , Boca/microbiologia , Adolescente , Adulto , Idoso , Bactérias/crescimento & desenvolvimento , Biodiversidade , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/microbiologia , Criança , Crowdsourcing/métodos , Cárie Dentária/etiologia , Cárie Dentária/microbiologia , Dieta/métodos , Disbiose/complicações , Disbiose/microbiologia , Feminino , Humanos , Estilo de Vida , Masculino , Pessoa de Meia-Idade , Obesidade/etiologia , Obesidade/microbiologia , Doenças Periodontais/etiologia , Doenças Periodontais/microbiologia , Adulto Jovem
16.
BMC Complement Med Ther ; 20(1): 45, 2020 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-32046702

RESUMO

BACKGROUND: Dental caries is one of the most prevalent chronic oral diseases worldwide. Dental caries is mainly associated with Streptococcus mutans and the Lactobacillus species. A specific relationship was found between nicotine and S. mutans growth as the presence of nicotine increased S. mutans biofilm formation. Nicotine is able to increase the number of S. mutans and extracellular polysaccharide (EPS) synthesis. Among the widely used herbs and spices is cinnamon which demonstrated a strong antibacterial activity against a wide variety of bacteria including S. mutans and showed the ability to inhibit S. mutans biofilm formation. Cinnamon essential oil, obtained from the leaves of C. zeylanicum, has been demonstrated to be effective against S. mutans and Lactobacillus acidophilus, which are partially responsible for dental plaque formation and caries development. The aim of this study was to identify the effects of nicotine exposure on the inhibitory effects of cinnamon water extract on S. mutans biofilm formation. MATERIALS AND METHODS: A 24-h culture of S. mutans UA159 in microtiter plates was treated with varying nicotine concentrations (0-32 mg/ml) in Tryptic Soy broth supplemented with 1% sucrose (TSBS) with or without a standardized concentration (2.5 mg/ml) of cinnamon water extract. A spectrophotometer was used to determine total growth absorbance and planktonic growth. The microtiter plate wells were washed, fixed and stained with crystal violet dye and the absorbance measured to determine biofilm formation. RESULTS: The presence of 2.5 mg/ml cinnamon water extract inhibits nicotine-induced S. mutans biofilm formation from 34 to 98% at different concentrations of nicotine (0-32 mg/ml). CONCLUSION: The results demonstrated nicotine-induced S. mutans biofilm formation is decreased from 34 to 98% in the presence of 2.5 mg/ml cinnamon water extract. This provides further evidence about the biofilm inhibitory properties of cinnamon water extract and reconfirms the harmful effects of nicotine.


Assuntos
Biofilmes/efeitos dos fármacos , Cariostáticos/farmacologia , Cinnamomum zeylanicum/química , Extratos Vegetais/farmacologia , Streptococcus mutans/efeitos dos fármacos , Antibacterianos/farmacologia , Cárie Dentária/tratamento farmacológico , Cárie Dentária/microbiologia , Testes de Sensibilidade Microbiana , Nicotina/efeitos adversos
17.
BMC Res Notes ; 13(1): 112, 2020 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-32103773

RESUMO

OBJECTIVE: This study aimed to determine the relative amounts of Streptococcus mutans (SM) and lactobacilli (LBs) and their relationship with dental caries among a Yemeni adult population. RESULTS: A positive correlation appeared between SM and LB counts from saliva and caries tissue samples and the decayed, missing and filled teeth (DMFT) score (p < 0.05). There was a significant correlation between SM and LBs in caries tissue (p < 0.05). However, there was no significant difference between SM and LBs isolated from saliva samples (p > 0.05). The number of SM and LBs in subjects with active caries was significantly higher than that in those without active caries (p < 0.05). There was no significant difference between the daily habits and SM and LB or DMFT scores (p > 0.05), except for a significant difference between brushing frequency and DMFT score (p < 0.05).


Assuntos
Cárie Dentária/diagnóstico , Lactobacillus/isolamento & purificação , Saliva/microbiologia , Streptococcus mutans/isolamento & purificação , Índice CPO , Cárie Dentária/microbiologia , Feminino , Humanos , Lactobacillus/fisiologia , Masculino , Streptococcus mutans/fisiologia , Escovação Dentária/métodos , Escovação Dentária/normas , Escovação Dentária/estatística & dados numéricos , Iêmen , Adulto Jovem
18.
Sci Rep ; 10(1): 2961, 2020 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-32076013

RESUMO

Sucrose has long been regarded as the most cariogenic carbohydrate. However, why sucrose causes severer dental caries than other sugars is largely unknown. Considering that caries is a polymicrobial infection resulting from dysbiosis of oral biofilms, we hypothesized that sucrose can introduce a microbiota imbalance favoring caries to a greater degree than other sugars. To test this hypothesis, an in vitro saliva-derived multispecies biofilm model was established, and by comparing caries lesions on enamel blocks cocultured with biofilms treated with sucrose, glucose and lactose, we confirmed that this model can reproduce the in vivo finding that sucrose has the strongest cariogenic potential. In parallel, compared to a control treatment, sucrose treatment led to significant changes within the microbial structure and assembly of oral microflora, while no significant difference was detected between the lactose/glucose treatment group and the control. Specifically, sucrose supplementation disrupted the homeostasis between acid-producing and alkali-producing bacteria. Consistent with microbial dysbiosis, we observed the most significant disequilibrium between acid and alkali metabolism in sucrose-treated biofilms. Taken together, our data indicate that the cariogenicity of sugars is closely related to their ability to regulate the oral microecology. These findings advance our understanding of caries etiology from an ecological perspective.


Assuntos
Biofilmes/efeitos dos fármacos , Cárie Dentária/microbiologia , Disbiose/induzido quimicamente , Microbiota/efeitos dos fármacos , Sacarose/efeitos adversos , Adulto , Contagem de Colônia Microbiana , Esmalte Dentário/microbiologia , Glucose/efeitos adversos , Humanos , Concentração de Íons de Hidrogênio , Lactose/efeitos adversos , Saliva/microbiologia
19.
Microbiology (Reading) ; 166(3): 306-317, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31935187

RESUMO

The MarR-like transcriptional regulator and two ABC transporters encoded by the rcrRPQ operon in the dental caries pathogen Streptococcus mutans have important regulatory roles related to oxidative stress tolerance, genetic competence and (p)ppGpp metabolism. A unique feature of the rcrRPQ operon, when compared to other bacteria, is the presence of two peptides, designated Pep1 and Pep2, encoded in alternative reading frames at the 3' end of rcrQ. Here, we show that the rcrRPQ operon, including Pep1 and 2, is essential for S. mutans to survive and maintain viability at elevated temperatures. No major changes in the levels of the heat shock proteins DnaK or GroEL that could account for the thermosensitivity of rcrRPQ mutants were observed. By introducing a single amino acid substitution into the comX gene that deletes an internally encoded peptide, XrpA, we found that XrpA is a contributing factor to the thermosensitive phenotype of a ΔrcrR strain. Overexpression of XrpA on a plasmid also caused a significant growth defect at 42 °C. Interestingly, loss of the gene for the RelA/SpoT homologue (RSH) enzyme, relA, restored growth of the ΔrcrR strain at 42 °C. During heat stress and when a stringent response was induced, levels of (p)ppGpp were elevated in the ΔrcrR strain. Deletion of relA in the ΔrcrR strain lowered the basal levels of (p)ppGpp to those observed in wild-type S. mutans. Thus, (p)ppGpp pools are dysregulated in ΔrcrR, which likely leads to aberrant control of transcriptional/translational processes and the thermosensitive phenotype. In summary, the genes and peptides encoded in the rcrRPQ operon are critical for thermotolerance, and in some strains these phenotypes are related to altered (p)ppGpp metabolism and increased production of the XrpA peptide.


Assuntos
Transportadores de Cassetes de Ligação de ATP/genética , Streptococcus mutans , Termotolerância/genética , Fatores de Transcrição/genética , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Biofilmes/crescimento & desenvolvimento , Cárie Dentária/microbiologia , Regulação Bacteriana da Expressão Gênica , Guanosina Pentafosfato/metabolismo , Guanosina Tetrafosfato/metabolismo , Óperon/genética , Peptídeos/genética , Peptídeos/metabolismo , Streptococcus mutans/genética , Streptococcus mutans/crescimento & desenvolvimento , Streptococcus mutans/metabolismo
20.
Biochem Biophys Res Commun ; 523(3): 561-566, 2020 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-31932035

RESUMO

In this study, we applied protamine, which is an antimicrobial peptide, to oral healthcare in combination with conventional antimicrobial agents. First, we explored the antimicrobial activity of protamine, with or without other antimicrobial agents, against Streptococcus mutans (S. mutans). Co-treatment with protamine and 3-methyl-4-isopropylphenol (IPMP) decreased the viability of S. mutans synergistically within 10 min. Interestingly, sodium fluoride (NaF) did not exhibit synergistic activity with protamine. Next, S. mutans and Streptococcus gordonii (S. gordonii) were co-treated with protamine and IPMP for 5 min to simulate tooth brushing. As a result, this co-treatment killed S. mutans faster than S. gordonii. Therefore, co-treatment with protamine and IPMP could be incorporated into oral healthcare products to prevent dental caries.


Assuntos
Antibacterianos/farmacologia , Protaminas/farmacologia , Streptococcus gordonii/efeitos dos fármacos , Streptococcus mutans/efeitos dos fármacos , Cárie Dentária/tratamento farmacológico , Cárie Dentária/microbiologia , Sinergismo Farmacológico , Humanos , Testes de Sensibilidade Microbiana , Fluoreto de Sódio/farmacologia , Infecções Estreptocócicas/prevenção & controle
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