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1.
PLoS One ; 16(3): e0248308, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33667279

RESUMO

Periodontitis can result in tooth loss and the associated chronic inflammation can provoke several severe systemic health risks. Adjunctive to mechanical treatment of periodontitis and as alternatives to antibiotics, the use of probiotic bacteria was suggested. In this study, the inhibitory effect of the probiotic Streptococcus salivarius subsp. salivarius strains M18 and K12, Streptococcus oralis subsp. dentisani 7746, and Lactobacillus reuteri ATCC PTA 5289 on anaerobic periodontal bacteria and Aggregatibacter actinomycetemcomitans was tested. Rarely included in other studies, we also quantified the inverse effect of pathogens on probiotic growth. Probiotics and periodontal pathogens were co-incubated anaerobically in a mixture of autoclaved saliva and brain heart infusion broth. The resulting genome numbers of the pathogens and of the probiotics were measured by quantitative real-time PCR. Mixtures of the streptococcal probiotics were also used to determine their synergistic, additive, or antagonistic effects. The overall best inhibitor of the periodontal pathogens was L. reuteri ATCC PTA 5289, but the effect is coenzyme B12-, anaerobiosis-, as well as glycerol-dependent, and further modulated by L. reuteri strain DSM 17938. Notably, in absence of glycerol, the pathogen-inhibitory effect could even turn into a growth spurt. Among the streptococci tested, S. salivarius M18 had the most constant inhibitory potential against all pathogens, followed by K12 and S. dentisani 7746, with the latter still having significant inhibitory effects on P. intermedia and A. actinomycetemcomitans. Overall, mixtures of the streptococcal probiotics did inhibit the growth of the pathogens equally or-in the case of A. actinomycetemcomitans- better than the individual strains. P. gingivalis and F. nucleatum were best inhibited by pure cultures of S. salivarius K12 or S. salivarius M18, respectively. Testing inverse effects, the growth of S. salivarius M18 was enhanced when incubated with the periodontal pathogens minus/plus other probiotics. In contrast, S. oralis subsp. dentisani 7746 was not much influenced by the pathogens. Instead, it was significantly inhibited by the presence of other streptococcal probiotics. In conclusion, despite some natural limits such as persistence, the full potential for probiotic treatment is by far not utilized yet. Especially, further exploring concerted activity by combining synergistic strains, together with the application of oral prebiotics and essential supplements and conditions, is mandatory.


Assuntos
Anaerobiose/efeitos dos fármacos , Periodontite/tratamento farmacológico , Porphyromonas gingivalis/efeitos dos fármacos , Probióticos/farmacologia , Aggregatibacter actinomycetemcomitans/química , Aggregatibacter actinomycetemcomitans/crescimento & desenvolvimento , Antibiose/efeitos dos fármacos , Humanos , Limosilactobacillus reuteri/química , Limosilactobacillus reuteri/crescimento & desenvolvimento , Periodontite/microbiologia , Periodontite/patologia , Porphyromonas gingivalis/patogenicidade , Probióticos/química , Saliva/efeitos dos fármacos , Saliva/microbiologia , Streptococcus/química , Streptococcus/crescimento & desenvolvimento , Streptococcus mutans/química , Streptococcus mutans/crescimento & desenvolvimento , Streptococcus salivarius/química , Streptococcus salivarius/crescimento & desenvolvimento
2.
Int J Biol Macromol ; 173: 99-108, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33460660

RESUMO

The present investigation reports an in-vitro study using combination of laccase and an enhancer capable of inhibiting the growth of pathogenic microorganisms, preventing biofilm formation, and whitening teeth. Laccase-cinnamic acid system remarkably inhibited the growth of Aggregatibacter actinomycetemcomitans, Candida albicans, S. aureus, and Streptococcus mutans whilst showed no significant effects on Gram-negative bacteria. Data presented that cinnamic acid (10 mM) with laccase (0.125 U ml-1) led to a maximum decrease of about 90%, in S. mutans biofilm formation. The confocal laser scanning microscopy showed considerable detachment of S. mutans cells from glass substratum. The combined laccase-cinnamic acid system could remove teeth discoloration caused by coffee. SEM of the teeth surface exhibited no damages such as surface cracking or fracture. Liquid chromatography-tandem mass spectrometry (LC-MS) and cyclic voltammetry (CV) studies showed that laccase can catalyze the one-electron oxidation of cinnamic acid to the respective radical. This radical can then undergo several fates, including recombination with another radical to form a dimeric species, dismutation of the radical back to cinnamic acid or decarboxylation to give various reduced oxygen species. Therefore, the redox potential values of phenolic monomers/oligomers are related with their biological activities.


Assuntos
Aggregatibacter actinomycetemcomitans/efeitos dos fármacos , Antibacterianos/farmacologia , Cinamatos/farmacologia , Proteínas Fúngicas/farmacologia , Hericium/química , Lacase/farmacologia , Aggregatibacter actinomycetemcomitans/crescimento & desenvolvimento , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Ácidos Cafeicos/farmacologia , Candida albicans/efeitos dos fármacos , Candida albicans/crescimento & desenvolvimento , Catecóis/farmacologia , Sinergismo Farmacológico , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Proteínas Fúngicas/isolamento & purificação , Ácido Gálico/farmacologia , Hericium/enzimologia , Hidroquinonas/farmacologia , Lacase/isolamento & purificação , Lactobacillus/efeitos dos fármacos , Lactobacillus/crescimento & desenvolvimento , Testes de Sensibilidade Microbiana , Oxirredução , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/crescimento & desenvolvimento , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/crescimento & desenvolvimento , Streptococcus mutans/efeitos dos fármacos , Streptococcus mutans/crescimento & desenvolvimento , Clareadores Dentários/farmacologia
3.
Arch Oral Biol ; 122: 104989, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33249361

RESUMO

OBJECTIVE: To determine the mechanism of growth inhibition of Aggregatibacter actinomycetemcomitans by Maillard reaction products (MRP). DESIGN: Growth and cell viabilities in the presence or absence of MRP were measured for both the rough and smooth variants of the bacteria. Effects of addition of ferrous and ferric ions on the inhibition of the bacteria by MRP were determined. RESULTS: MRPs decreased the extent of complex formation of Chrome Azurol S with iron suggesting that MRPs can chelate iron effectively. The chelation causes growth inhibition of both the rough and smooth strains. At low concentrations of the inhibitor, lag time was extended by approximately 12 h while at high concentrations, cells were killed, decreasing cell viability by up to 8 orders of magnitude. Growth of both the rough and smooth strains could be restored to original level by addition of iron. For the rough strain, both ferrous and ferric ions could relieve the inhibition by MRP while for the smooth strain only ferrous ion was effective. CONCLUSION: MRPs inhibit the growth of A. actinomycetemcomitans by chelating iron and the inhibition can be relieved by addition of iron.


Assuntos
Aggregatibacter actinomycetemcomitans/efeitos dos fármacos , Quelantes/farmacologia , Produtos Finais de Glicação Avançada , Ferro/farmacologia , Aggregatibacter actinomycetemcomitans/crescimento & desenvolvimento , Hidroxibenzoatos/farmacologia , Reação de Maillard
4.
São José dos Campos; s.n; 2021. 49 p. il., tab., graf..
Tese em Português | LILACS, BBO - Odontologia | ID: biblio-1281098

RESUMO

A etiopatogenia da doença periodontal é complexa e exige estudos constantes em alternativas terapêuticas que possibilitem seu controle. Aggregatibacter actinomycetemcomitans está associado fortemente à periodontite crônica e à periodontite agressiva. A tecnologia do plasma frio sob pressão atmosférica tem potencial para uso na odontologia, mas sua aplicação na periodontia ainda é pouco explorada. Este estudo teve como objetivo avaliar os efeitos do plasma de baixa temperatura sob pressão atmosférica (PBTPA) como adjuvante no controle da doença periodontal experimental induzida por ligadura, inoculada com A. actinomycetemcomitans, na região cervical do primeiro molar inferior em modelo murino. Inicialmente, foram determinados os parâmetros físicos efetivos para inibição de biofilmes de A. actinomycetemcomitans utilizando cepa padrão American Type Culture Collection ATCC 29523. Foram realizados testes de screening inicial com a verificação da inibição do crescimento por exposição ao PBTPA de A. actinomycetemcomitans semeados em placas de Petri. Posteriormente, foram formados biofilmes em placas de microtitulação e foram determinados os parâmetros físicos efetivos do PBTPA. Foram realizados experimentos in vivo de indução de doença periodontal por A. actinomycetemcomitans em modelo utilizando ligaduras em ratos. A tomografia computadorizada de feixe cônico foi utilizada para avaliar o nível de perda óssea após período experimental. Os resultados mostraram que o PBTPA foi efetivo na eliminação do micro-organismo observado através da formação de halos de inibição nos tempos de 5 e 7, 5 minutos e sobre biofilmes de A. actinomycetemcomitans expostos ao PBTPA no tempo de 5 minutos. Os resultados exibiram diferença estatística significativa (p <0,001) na distância entre a junção esmalte-cemento e a crista óssea alveolar, do grupo tratado com PBTPA em relação ao grupo raspagem e ao grupo controle. Os resultados do presente estudo sugerem o potencial do PBTPA no controle da periodontite induzida, contudo análises adicionais são necessárias(AU)


The etiopathogenesis of periodontal disease is complex requiring constant studies of therapeutic alternatives that enable its control. Aggregatibacter actinomycetemcomitans is strongly associated with chronic periodontitis and aggressive periodontitis. Cold plasma technology under atmospheric pressure has potential for use in dentistry, but its application in periodontics is still not well explored. This study aimed to evaluate the effects of low temperature atmospheric pressure plasma (PBTPA) as an adjuvant in the control of experimental periodontal disease induced by ligature inoculated with A. actinomycetemcomitans in the cervical region of the lower 1st molar in a murine model. Initially, effective physical parameters for inhibition of A. actinomycetemcomitans biofilms were determined using the standard strain American Type Culture Collection ATCC 29523. Initial screening tests were performed to verify growth inhibition after exposure of A. actinomycetemcomitans seeded in Petri dishes to the PBTPA. Subsequently, biofilms were formed on microtiter plates and the effective physical parameters of the PBTPA were determined. In vivo experiments were carried out to induce A. actinomycetemcomitans periodontal disease induced by ligature in a rat model. Cone beam computed tomography was used to assess the level of bone loss after the experimental period. The results showed that PBTPA was effective in eliminating the microorganism observed through the formation of halos inhibition during 5 and 7.5 minutes and in A. actinomycetemcomitans biofilms exposed to PBTPA at 5 minutes. The previous study using PBTPA in 5 minutes did not show cytotoxicity in Vero cells. The results showed a statistically significant difference (p <0.0001) in the distance between the enamel-cement joint and the alveolar bone crest, of the group treated with PBTPA in relation to the scalling group and the control group, confirming the potential of the technique in dentistry(AU)


Assuntos
Periodontite/complicações , Aggregatibacter actinomycetemcomitans/crescimento & desenvolvimento , Gases em Plasma/efeitos adversos
5.
Pathog Dis ; 78(8)2020 11 11.
Artigo em Inglês | MEDLINE | ID: mdl-32845308

RESUMO

Periodontitis is a multifactorial inflammatory disease, and the major cause of tooth loss in adults. New therapies have been proposed for its treatment, including the use of probiotics such as Lactobacillus reuteri. The objective of this study was to evaluate the antimicrobial effects of L. reuteri: live, heat-killed and culture filtrate (cell-free supernatant), on periodontopathogenic bacteria (Fusobacterium nucleatum and Aggregatibacter actinomycetemcomitans) in vitro, as well as the in vivo survival curve, hemocyte density and microbial recovery using Galleria mellonella. For in vitro assays, all preparations reduced colony forming units of F. nucleatum, while only live L. reuteri reduced the growth of A. actinomycetemcomitans. All treatments reduced periodontopathogenic bacteria growth in vivo. The treatment with the supernatant increased the survival of larvae infected with F. nucleatum more than the treatment with live L. reuteri, and none of the treatments altered the survival of A. actinomycetemcomitans-infected larvae. In addition, the treatment with L. reuteri preparations did not alter the hemocyte count of F. nucleatum- and A. actinomycetemcomitans-infected larvae. This study demonstrated that L. reuteri preparations exerted antimicrobial effects and increased the survival of G. mellonella infected by F. nucleatum, although only live L. reuteri was able to reduce the growth of A. actinomycetemcomitans in vitro.


Assuntos
Aggregatibacter actinomycetemcomitans/crescimento & desenvolvimento , Infecções por Fusobacterium/terapia , Fusobacterium nucleatum/crescimento & desenvolvimento , Limosilactobacillus reuteri/fisiologia , Infecções por Pasteurellaceae/terapia , Probióticos/uso terapêutico , Animais , Infecções por Fusobacterium/microbiologia , Hemócitos/microbiologia , Humanos , Larva/microbiologia , Interações Microbianas , Modelos Animais , Mariposas/microbiologia , Infecções por Pasteurellaceae/microbiologia , Periodontite/microbiologia , Periodontite/terapia , Análise de Sobrevida
6.
Sci Rep ; 10(1): 8553, 2020 05 22.
Artigo em Inglês | MEDLINE | ID: mdl-32444858

RESUMO

This study investigated the bactericidal effect, the underlying mechanisms of treatment, and recovery of biocompatibility of the infected titanium surface using a combination treatment of silver ion application and ultraviolet-A (UV-A) light irradiation. Streptococcus mutans and Aggregatibacter actinomycetemcomitans were used in suspension and as a biofilm on a titanium surface to test for the bactericidal effect. The bactericidal effect of the combination treatment was significantly higher than that of silver ion application or UV-A light irradiation alone. The bactericidal effect of the combination treatment was attributable to hydroxyl radicals, which generated from the bacterial cell wall and whose yield increased with the silver concentration. To assess the biocompatibility, proliferation and calcification of MC3T3E1 cells were evaluated on the treated titanium surface. The treated titanium screws were implanted into rat tibias and the removal torques were measured 28 days post-surgery. The titanium surface that underwent the combination treatment exhibited recovery of biocompatibility by allowing cellular proliferation or calcification at levels observed in the non-infected titanium surfaces. The removal torque 28 days after surgery was also comparable to the control values. This approach is a novel treatment option for peri-implantitis.


Assuntos
Aggregatibacter actinomycetemcomitans/crescimento & desenvolvimento , Antibacterianos/administração & dosagem , Biofilmes/crescimento & desenvolvimento , Radical Hidroxila/química , Infecções por Pasteurellaceae/prevenção & controle , Prata/administração & dosagem , Streptococcus mutans/crescimento & desenvolvimento , Titânio/química , Aggregatibacter actinomycetemcomitans/efeitos dos fármacos , Aggregatibacter actinomycetemcomitans/efeitos da radiação , Animais , Antibacterianos/química , Biofilmes/efeitos dos fármacos , Biofilmes/efeitos da radiação , Camundongos , Infecções por Pasteurellaceae/microbiologia , Peri-Implantite/microbiologia , Peri-Implantite/terapia , Ratos , Ratos Wistar , Prata/química , Streptococcus mutans/efeitos dos fármacos , Streptococcus mutans/efeitos da radiação , Tíbia/microbiologia , Tíbia/cirurgia , Raios Ultravioleta
7.
Artigo em Inglês | MEDLINE | ID: mdl-31605582

RESUMO

INTRODUCTION: The present study aimed to assess the presence of main types of microorganisms involved in the aetiopathogenesis of chronic periodontitis with PCR technique and determinates the presence of composite IL-1 genotype and their associations with founded bacteria. MATERIAL AND METHOD: The examined group was consisted from 20 subjects with diagnosed chronic periodontitis and 20 healthy control without periodontitis. Clinical parameters like gingival index (GI), plaque index (PI), bleeding on probing (BOP), periodontal pocket depth (PPD) and clinical attachment lost (CAL) were determinates. Subgingival dental plaque was collected using a sterilized paper point. We used Parodontose Plus test, reverse hybridization kit, for the detection of periodontal marker bacteria, as well as for the detection of composite Interleukin -1 Genotype Results: The most present bacterial species detected from subgingival dental plaque was Treponema denticola and Porfiromonas gingivalis which was present in 65% of examined patients. In relation to the presence of positive genotype in patients, there was no significant difference between the test and control group for p> 0.05 (p = 1.00). For χ2=8,17 (p=0,06, p<0,05) there is an association between Prevotella intermedia, and composite genotype. Between positive genotype and analyzed bacterial species A. actinomycetem comitans for p> 0.05 (p = 1.00), P. gingivalis for p> 0.05 (p = 0.16), T. Forsythia for p> 0.05 (p = 0.20), T. Denticola for p> 0.05 (p = 0.64) no association was found. CONCLUSION: This investigations confirmed the strong association of these five examined periopathogenes with periodontitis.


Assuntos
Periodontite Crônica/microbiologia , Placa Dentária/microbiologia , Interleucina-1/genética , Adulto , Aggregatibacter actinomycetemcomitans/genética , Aggregatibacter actinomycetemcomitans/crescimento & desenvolvimento , Aggregatibacter actinomycetemcomitans/isolamento & purificação , Periodontite Crônica/metabolismo , Placa Dentária/metabolismo , Índice de Placa Dentária , Genótipo , Humanos , Pessoa de Meia-Idade , Índice Periodontal , Bolsa Periodontal/microbiologia , Reação em Cadeia da Polimerase/métodos , Porphyromonas gingivalis/genética , Porphyromonas gingivalis/crescimento & desenvolvimento , Porphyromonas gingivalis/isolamento & purificação , Prevotella intermedia/genética , Prevotella intermedia/crescimento & desenvolvimento , Prevotella intermedia/isolamento & purificação , Treponema denticola/genética , Treponema denticola/crescimento & desenvolvimento , Treponema denticola/isolamento & purificação
8.
Oral Dis ; 25(2): 569-579, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30506613

RESUMO

OBJECTIVE: To evaluate the effect of the periodontal treatment on Aggregatibacter actinomycetemcomitans JP2 clone, and the IgG serum levels against its outer membrane protein (Omp29) and A. actinomycetemcomitans serotypes in aggressive periodontitis (AgP). SUBJECTS AND METHODS: Seventeen patients with generalized (GAgP), 10 with localized (LAgP), and 10 healthy controls were included. AgP participants were submitted to periodontal treatment-scaling and root planing plus antibiotics (SRP+A). Periodontal parameters, for example, probing depth (PD) and clinical attachment loss (CAL), were evaluated at baseline and at 1-year. Serum IgG against Omp29 and serotypes a, b, and c were determined by ELISA. The levels of A. actinomycetemcomitans JP2 clone were determined in subgingival biofilm samples by qPCR. RESULTS: Periodontal treatment resulted in significant reductions of PD, CAL, and IgG levels against Omp29, serotypes b, and c. After therapy, IgG levels against A. actinomycetemcomitans serotypes, as well as the levels of the JP2 clone in AgP, became similar to controls. The reduction in JP2 clone count was correlated with a reduction of PD and IgG response against Omp29. CONCLUSION: Scaling and root planing plus antibiotics decreased IgG levels response against Omp29 and A. actinomycetemcomitans serotypes involved in the disease (b and c), while the serum response increased against tne commensal serotype (a), similar to what occurs in periodontally healthy individuals.


Assuntos
Aggregatibacter actinomycetemcomitans/crescimento & desenvolvimento , Aggregatibacter actinomycetemcomitans/imunologia , Periodontite Agressiva/microbiologia , Periodontite Agressiva/terapia , Proteínas da Membrana Bacteriana Externa/imunologia , Imunoglobulina G/sangue , Adolescente , Adulto , Periodontite Agressiva/sangue , Periodontite Agressiva/complicações , Amoxicilina/uso terapêutico , Antibacterianos/uso terapêutico , Contagem de Colônia Microbiana , Feminino , Humanos , Masculino , Metronidazol/uso terapêutico , Perda da Inserção Periodontal/microbiologia , Índice Periodontal , Estudos Prospectivos , Aplainamento Radicular , Sorogrupo , Adulto Jovem
9.
Mol Cell Probes ; 43: 45-49, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30471338

RESUMO

Peptide nucleic acids (PNA) are DNA/RNA analogs in which the sugar-phosphate backbone is replaced by N-2-aminoethylglycine. PNA are widely used for experimental antisense therapy due to their strong affinity to mRNA. By targeting specific genes, protein synthesis and the growth of bacteria or cancer cells can be inhibited by PNA. Here, we report the design and evaluation of antisense PNA for selective growth inhibition of Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans, potent pathogens associated with periodontitis. Antisense PNA against groEL and acpP were prepared with carrier peptide (KFFKFFKFFK). Anti-groEL PNA for P. gingivalis specifically inhibited growth in a dose-dependent manner, and growth was inhibited for 5 h at a concentration of 3 µM. Anti-groEL PNA for A. actinomycetemcomitans inhibited growth for 2 h at a concentration of 3 µM with reduced GroEL protein expression. Anti-acpP PNA did not show a marked growth inhibitory effect on either species. Although further studies are needed to develop more effective antisense PNA for both species, anti-groEL PNA may be potentially useful species-specific antibacterial tools against oral pathogens.


Assuntos
Aggregatibacter actinomycetemcomitans/crescimento & desenvolvimento , Oligonucleotídeos Antissenso/farmacologia , Ácidos Nucleicos Peptídicos/farmacologia , Porphyromonas gingivalis/crescimento & desenvolvimento , Aggregatibacter actinomycetemcomitans/efeitos dos fármacos , Chaperonina 60/metabolismo , Porphyromonas gingivalis/efeitos dos fármacos
10.
Drug Deliv Transl Res ; 9(2): 434-443, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-29392681

RESUMO

The objectives of present research were to develop and characterize thermosensitive and mucoadhesive polymer-based sustained release moxifloxacin in situ gels for the treatment of periodontal diseases. Poloxamer- and chitosan-based in situ gels are in liquid form at room temperature and transform into gel once administered into periodontal pocket due to raise in temperature to 37 °C. Besides solution-to-gel characteristic of polymers, their mucoadhesive nature aids the gel to adhere to mucosa in periodontal pocket for prolonged time and releases the drug in sustained manner. These formulations were prepared using cold method and evaluated for pH, solution-gel temperature, syringeability and viscosity. In vitro drug release studies were conducted using dialysis membrane at 37 °C and 50 rpm. Antimicrobial studies carried out against Aggregatibacter actinomycetemcomitans (A.A.) and Streptococcus mutans (S. Mutans) using agar cup-plate method. The prepared formulations were clear and pH was at 7.01-7.40. The viscosity of formulations was found to be satisfactory. Among the all, formulations comprising of 21% poloxamer 407 and 2% poloxamer 188 (P5) and in combination with 0.5% HPMC (P6) as well as 2% chitosan and 70% ß-glycerophosphate (C6) demonstrated an ideal gelation temperature (33-37 °C) and sustained the drug release for 8 h. Formulations P6 and C6 showed promising antimicrobial efficacy with zone of inhibition of 27 mm for A.A. and 55 mm for S. Mutans. The developed sustained release in situ gel formulations could enhance patient's compliance by reducing the dosing frequency and also act as an alternative treatment to curb periodontitis.


Assuntos
Antibacterianos/administração & dosagem , Moxifloxacina/administração & dosagem , Polímeros/administração & dosagem , Adesividade , Aggregatibacter actinomycetemcomitans/efeitos dos fármacos , Aggregatibacter actinomycetemcomitans/crescimento & desenvolvimento , Antibacterianos/química , Preparações de Ação Retardada/administração & dosagem , Preparações de Ação Retardada/química , Liberação Controlada de Fármacos , Géis , Glicerofosfatos/administração & dosagem , Glicerofosfatos/química , Mucosa Bucal , Moxifloxacina/química , Periodonto , Polímeros/química , Soluções , Streptococcus mutans/efeitos dos fármacos , Streptococcus mutans/crescimento & desenvolvimento , Temperatura , Viscosidade
11.
Infect Immun ; 87(1)2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30297525

RESUMO

Periodontitis is an inflammatory disease caused by polymicrobial biofilms. The periodontal pathogen Aggregatibacter actinomycetemcomitans displays two proteinaceous surface structures, the fimbriae and the nonfimbrial extracellular matrix binding protein A (EmaA), as observed by electron microscopy. Fimbriae participate in biofilm biogenesis and the EmaA adhesins mediate collagen binding. However, in the absence of fimbriae, A. actinomycetemcomitans still retains the potential to form robust biofilms, suggesting that other surface macromolecules participate in biofilm development. Here, isogenic mutant strains lacking EmaA structures, but still expressing fimbriae, were observed to have reduced biofilm potential. In strains lacking both EmaA and fimbriae, biofilm mass was reduced by 80%. EmaA enhanced biofilm formation in different strains, independent of the fimbriation state or serotype. Confocal microscopy revealed differences in cell density within microcolonies between the EmaA positive and mutant strains. EmaA-mediated biofilm formation was found to be independent of the glycosylation state and the precise three-dimensional conformation of the protein, and thus this function is uncorrelated with collagen binding activity. The data suggest that EmaA is a multifunctional adhesin that utilizes different mechanisms to enhance bacterial binding to collagen and to enhance biofilm formation, both of which are important for A. actinomycetemcomitans colonization and subsequent infection.


Assuntos
Adesinas Bacterianas/metabolismo , Aggregatibacter actinomycetemcomitans/crescimento & desenvolvimento , Biofilmes/crescimento & desenvolvimento , Adesinas Bacterianas/genética , Aggregatibacter actinomycetemcomitans/metabolismo , Fímbrias Bacterianas/genética , Fímbrias Bacterianas/metabolismo , Deleção de Genes , Humanos
12.
PLoS One ; 13(10): e0205871, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30335797

RESUMO

The oral bacterium, Aggregatibacter actinomycetemcomitans, which is associated with localized aggressive periodontitis, as well as systemic infections including endocarditis, produces numerous virulence factors, including a repeats-in-toxin (RTX) protein called leukotoxin (LtxA), which kills human immune cells. The strains of A. actinomycetemcomitans most closely associated with disease have been shown to produce the most LtxA, suggesting that LtxA plays a significant role in the virulence of this organism. LtxA, like many of the RTX toxins, can be divided into four functional domains: an N-terminal hydrophobic domain, which contains a significant fraction of hydrophobic residues and has been proposed to play a role in the membrane interaction of the toxin; the central domain, which contains two lysine residues that are the sites of post-translational acylation; the repeat domain that is characteristic of the RTX toxins, and a C-terminal domain thought to be involved in secretion. In its initial interaction with the host cell, LtxA must bind to both cholesterol and an integrin receptor, lymphocyte function-associated antigen-1 (LFA-1). While both interactions are essential for toxicity, the domains of LtxA involved remain unknown. We therefore undertook a series of experiments, including tryptophan quenching and trypsin digestion, to characterize the structure of LtxA upon interaction with membranes of various lipid compositions. Our results demonstrate that LtxA adopts a U-shaped conformation in the membrane, with the N- and C-terminal domains residing outside of the membrane.


Assuntos
Aggregatibacter actinomycetemcomitans/química , Proteínas de Bactérias/química , Colesterol/química , Proteínas Hemolisinas/química , Antígeno-1 Associado à Função Linfocitária/química , Fatores de Virulência/química , Aggregatibacter actinomycetemcomitans/crescimento & desenvolvimento , Aggregatibacter actinomycetemcomitans/patogenicidade , Sequência de Aminoácidos , Proteínas de Bactérias/isolamento & purificação , Proteínas de Bactérias/metabolismo , Sítios de Ligação , Colesterol/metabolismo , Dimiristoilfosfatidilcolina/química , Dimiristoilfosfatidilcolina/metabolismo , Proteínas Hemolisinas/isolamento & purificação , Proteínas Hemolisinas/metabolismo , Humanos , Interações Hidrofóbicas e Hidrofílicas , Células Jurkat , Bicamadas Lipídicas/química , Bicamadas Lipídicas/metabolismo , Lipossomos/química , Lipossomos/metabolismo , Antígeno-1 Associado à Função Linfocitária/metabolismo , Fosfatidiletanolaminas/química , Fosfatidiletanolaminas/metabolismo , Ligação Proteica , Domínios e Motivos de Interação entre Proteínas , Estrutura Secundária de Proteína , Proteólise , Tripsina/química , Fatores de Virulência/isolamento & purificação , Fatores de Virulência/metabolismo
13.
Gen Dent ; 66(5): 39-44, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30188855

RESUMO

The characteristics of prosthetic implant components, such as the type, material, and surface roughness of abutments, can affect biofilm formation. Since an ideal abutment surface for the reduction of bacterial adhesion has yet to be found, this in vitro study aimed to quantify biofilm formation on laser-treated titanium, zirconia, and titanium surfaces. Sterile titanium, zirconia, and laser-treated titanium discs were placed in sterile 48-well plates. Biofilm formation was induced by adding sterilized, unstimulated human saliva and suspensions of Porphyromonas gingivalis (Pg), Aggregatibacter actinomycetemcomitans (Aa), and Prevotella intermedia (Pi) to the wells. Viable bacteria in the biofilm were quantified with real-time polymerase chain reaction in conjunction with propidium monoazide. The disc material, the type of bacteria, and their interactions had significant effects on the bacterial counts. On all surfaces, the Pg count was significantly higher than both the Pi and Aa counts (P = 0.0001). The highest count of periodontal pathogens was found on laser-treated surfaces. The second highest and the lowest counts were found on zirconia and titanium surfaces, respectively.


Assuntos
Biofilmes/crescimento & desenvolvimento , Dente Suporte/microbiologia , Aggregatibacter actinomycetemcomitans/crescimento & desenvolvimento , Azidas , Carga Bacteriana , Humanos , Porphyromonas gingivalis/crescimento & desenvolvimento , Prevotella intermedia/crescimento & desenvolvimento , Propídio/análogos & derivados , Reação em Cadeia da Polimerase em Tempo Real , Saliva/microbiologia , Propriedades de Superfície , Titânio , Zircônio
14.
J Microbiol Methods ; 148: 74-77, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29627600

RESUMO

Aggregatibacter (A.) actinomycetemcomitans is a periodontopathogenic bacterium causing aggressive periodontitis. Here we describe a single-step transconjugation system as novel and easily applicable protocol for site-specific genetic manipulation of A. actinomycetemcomitans. Deletion of PgaC, which is involved in the synthesis of biofilm matrix, led to a reduced biofilm formation.


Assuntos
Aggregatibacter actinomycetemcomitans/genética , Deleção de Genes , Técnicas de Inativação de Genes/métodos , Aggregatibacter actinomycetemcomitans/crescimento & desenvolvimento , Proteínas de Bactérias/genética , Biofilmes/crescimento & desenvolvimento
15.
Nutrients ; 10(4)2018 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-29649103

RESUMO

Poor oral health and related diseases, including caries, periodontal disease, and oral cancer, are highly prevalent across the world, particularly in the elderly. This study aimed to investigate the anti-periodontitis activity of fermented skim milk produced using the promising probiotic Lactobacillus paracasei subsp. paracasei NTU 101 (NTU101FM). An initial analysis found that an ethanol extract of NTU101FM displayed anti-oxidative activities. Further investigation of pathogen growth inhibition zones, minimum inhibitory concentrations (MICs), and minimum bactericidal concentrations (MBCs) revealed that the NTU101FM ethanol extract also had anti-periodontal pathogen activities. In addition, the NTU101FM ethanol extract significantly decreased the release of pro-inflammatory cytokines induced by lipopolysaccharide (LPS) in RAW 264.7 macrophage cells. Finally, the NTU101FM ethanol extract was found to inhibit receptor activator of nuclear factor-κB ligand (RANKL)-induced osteoclast differentiation by reducing tartrate-resistant acid phosphatase (TRAP) activity and the number of TRAP-positive multinucleated osteoclasts. In summary, our study demonstrated that ethanol extract prepared from NTU101FM has potential use as an anti-periodontitis agent.


Assuntos
Antibacterianos/farmacologia , Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Produtos Fermentados do Leite/microbiologia , Etanol/química , Lacticaseibacillus paracasei/fisiologia , Periodontite/prevenção & controle , Solventes/metabolismo , Aggregatibacter actinomycetemcomitans/efeitos dos fármacos , Aggregatibacter actinomycetemcomitans/crescimento & desenvolvimento , Animais , Antibacterianos/isolamento & purificação , Anti-Inflamatórios/isolamento & purificação , Antioxidantes/isolamento & purificação , Reabsorção Óssea/metabolismo , Reabsorção Óssea/prevenção & controle , Citocinas/metabolismo , Relação Dose-Resposta a Droga , Mediadores da Inflamação/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , Osteoclastos/efeitos dos fármacos , Osteoclastos/metabolismo , Osteogênese/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Periodontite/metabolismo , Periodontite/microbiologia , Porphyromonas gingivalis/efeitos dos fármacos , Porphyromonas gingivalis/crescimento & desenvolvimento , Ligante RANK/metabolismo , Células RAW 264.7 , Fosfatase Ácida Resistente a Tartarato/metabolismo
16.
Kaohsiung J Med Sci ; 34(4): 186-193, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29655406

RESUMO

Aggregatibacter (Actinobacillus) actimycetemcomitans (Aa) is a gram-negative bacterium that colonizes the human oral cavity and is causative agent for localized aggressive (juvenile) periodontitis (AgP). In the middle of 1990s, a specific JP2 clone of belonging to the cluster of serotype b strains of Aa with highly leukotoxicity (leukotoxin, LtxA) able to kill human immune cells was isolated. JP2 clone of Aa was strongly associated with in particularly in rapidly progressing forms of aggressive periodontitis. The JP2 clone of Aa is transmitted through close contacts. Therefore, AgP patients need intense monitoring of their periodontal status as the risk for developing severely progressing periodontitis lesions are relatively high. Furthermore, timely periodontal treatment, including periodontal surgery supplemented by the use of antibiotics, is warranted. More importantly, periodontal attachment loss should be prevented by early detection of the JP2 clone of Aa by microbial diagnosis testing and/or preventive means.


Assuntos
Aggregatibacter actinomycetemcomitans/patogenicidade , Periodontite Agressiva/história , Exotoxinas/história , Interações Hospedeiro-Patógeno , Leucócitos Mononucleares/efeitos dos fármacos , Infecções por Pasteurellaceae/história , Aggregatibacter actinomycetemcomitans/crescimento & desenvolvimento , Aggregatibacter actinomycetemcomitans/metabolismo , Periodontite Agressiva/genética , Periodontite Agressiva/imunologia , Periodontite Agressiva/microbiologia , Caspase 1/genética , Caspase 1/imunologia , Morte Celular/efeitos dos fármacos , Células Clonais , Exotoxinas/metabolismo , Exotoxinas/toxicidade , Regulação da Expressão Gênica , História do Século XX , Humanos , Interleucina-18/genética , Interleucina-18/imunologia , Interleucina-1beta/genética , Interleucina-1beta/imunologia , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/microbiologia , Antígeno-1 Associado à Função Linfocitária/genética , Antígeno-1 Associado à Função Linfocitária/imunologia , Boca/microbiologia , Boca/patologia , Infecções por Pasteurellaceae/genética , Infecções por Pasteurellaceae/imunologia , Infecções por Pasteurellaceae/microbiologia , Ligação Proteica , Transdução de Sinais
17.
Probiotics Antimicrob Proteins ; 10(3): 485-495, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-28631250

RESUMO

A specific strain of naturally occurring oral lactobacilli was isolated and identified based on morphological, biochemical, and 16S rRNA gene sequencing. The phylogenetic affiliation of the isolate confirmed that the NK02 strain had close association with the Lactobacillus salivarius. An effective mouthwash was developed for treatment of periodontitis and suppression of the indicator bacterium Aggregatibacter actinomycetemcomitans which is an obvious pathogen of periodontal disease. The mouthwash containing L. salivarius NK02 was tested at a dose level of 108 (colony forming units (CFU) ml-1), monitoring over a period of 4 weeks. The study was a randomized double-blind placebo control trial, and the patients were treated in two groups of control and test by using scaling and root planing (SRP) + placebo and scaling and root planing (SRP) + probiotic, respectively. It appeared that the probiotic mouthwash was able to inhibit the bacterial growth on both saliva and sub-gingival crevice and exhibited antibacterial activity against A. actinomycetemcomitans. The results also showed that SRP+ probiotic treatment led to a significant decrease of gingival index (GI) and bleeding on probing (BOP) compared with that of SRP + placebo for the probiotic group. The rate of decrease in pocket depth was displayed in the group with SRP + probiotic treatment equal to 1/2 mm, and probing pocket depth (PPD) value was decreased in the probiotic bacteria treatment group that can explain the decrease in inflammation in gingiva. Our findings suggest that probiotic mouthwash is healthy for daily use as an alternative for maintaining dental and periodontal health.


Assuntos
Ligilactobacillus salivarius/fisiologia , Antissépticos Bucais/administração & dosagem , Periodontite/tratamento farmacológico , Probióticos/administração & dosagem , Adulto , Aggregatibacter actinomycetemcomitans/crescimento & desenvolvimento , Antibiose , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Periodontite/microbiologia , Filogenia
18.
Molecules ; 22(12)2017 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-29206142

RESUMO

In this study, the essential oils of Orthosiphon stamineus Benth and Ficus deltoidea Jack were evaluated for their antibacterial activity against invasive oral pathogens, namely Enterococcus faecalis, Streptococcus mutans, Streptococcus mitis, Streptococcus salivarius, Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis and Fusobacterium nucleatum. Chemical composition of the oils was analyzed using gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS). The antibacterial activity of the oils and their major constituents were investigated using the broth microdilution method (minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC)). Susceptibility test, anti-adhesion, anti-biofilm, checkerboard and time-kill assays were also carried out. Physiological changes of the bacterial cells after exposure to the oils were observed under the field emission scanning electron microscope (FESEM). O. stamineus and F. deltoidea oils mainly consisted of sesquiterpenoids (44.6% and 60.9%, respectively), and ß-caryophyllene was the most abundant compound in both oils (26.3% and 36.3%, respectively). Other compounds present in O. stamineus were α-humulene (5.1%) and eugenol (8.1%), while α-humulene (5.5%) and germacrene D (7.7%) were dominant in F. deltoidea. The oils of both plants showed moderate to strong inhibition against all tested bacteria with MIC and MBC values ranging 0.63-2.5 mg/mL. However, none showed any inhibition on monospecies biofilms. The time-kill assay showed that combination of both oils with amoxicillin at concentrations of 1× and 2× MIC values demonstrated additive antibacterial effect. The FESEM study showed that both oils produced significant alterations on the cells of Gram-negative bacteria as they became pleomorphic and lysed. In conclusion, the study indicated that the oils of O. stamineus and F. deltoidea possessed moderate to strong antibacterial properties against the seven strains pathogenic oral bacteria and may have caused disturbances of membrane structure or cell wall of the bacteria.


Assuntos
Antibacterianos/farmacologia , Ficus/química , Boca/microbiologia , Óleos Voláteis/farmacologia , Orthosiphon/química , Sesquiterpenos/farmacologia , Aggregatibacter actinomycetemcomitans/efeitos dos fármacos , Aggregatibacter actinomycetemcomitans/crescimento & desenvolvimento , Aggregatibacter actinomycetemcomitans/isolamento & purificação , Amoxicilina/farmacologia , Antibacterianos/química , Antibacterianos/isolamento & purificação , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Sinergismo Farmacológico , Enterococcus faecalis/efeitos dos fármacos , Enterococcus faecalis/crescimento & desenvolvimento , Enterococcus faecalis/isolamento & purificação , Fusobacterium nucleatum/efeitos dos fármacos , Fusobacterium nucleatum/crescimento & desenvolvimento , Fusobacterium nucleatum/isolamento & purificação , Humanos , Testes de Sensibilidade Microbiana , Boca/patologia , Óleos Voláteis/química , Óleos Voláteis/isolamento & purificação , Sesquiterpenos Policíclicos , Porphyromonas gingivalis/efeitos dos fármacos , Porphyromonas gingivalis/crescimento & desenvolvimento , Porphyromonas gingivalis/isolamento & purificação , Sesquiterpenos/química , Sesquiterpenos/isolamento & purificação , Streptococcus mitis/efeitos dos fármacos , Streptococcus mitis/crescimento & desenvolvimento , Streptococcus mitis/isolamento & purificação , Streptococcus mutans/efeitos dos fármacos , Streptococcus mutans/crescimento & desenvolvimento , Streptococcus mutans/isolamento & purificação , Streptococcus salivarius/efeitos dos fármacos , Streptococcus salivarius/crescimento & desenvolvimento , Streptococcus salivarius/isolamento & purificação
19.
Nanotechnology ; 28(50): 505103, 2017 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-29058684

RESUMO

The main limitation of conventional antibiotic therapies concerns the low efficacy to fight bacteria attacks during long treatment times. In this context, the integrated use of electrofluidodynamics (EFDs)-basically electrospinning and electrospraying-may represent an interesting route for designing nanostructured platforms with controlled release to prevent the formation of bacterial biofilms in oral implant sites. They allow for the deposition of nanofibres and nanoparticles by different modes-i.e. sequential, simultaneous-for the fabrication of more efficacious systems in terms of degradation protection, pharmacokinetic control and drug distribution to the surrounding tissues. Herein, we will investigate EFDs processing modes and conditions to decorate polycaprolactone nanofibres surfaces by chitosan nano-reservoirs for the administration of Amoxicillin Trihydrate as an innovative antibacterial treatment of the periodontal pocket.


Assuntos
Amoxicilina/farmacologia , Antibacterianos/farmacologia , Quitosana/química , Portadores de Fármacos , Poliésteres/química , Aggregatibacter actinomycetemcomitans/efeitos dos fármacos , Aggregatibacter actinomycetemcomitans/crescimento & desenvolvimento , Amoxicilina/metabolismo , Antibacterianos/metabolismo , Preparações de Ação Retardada/síntese química , Composição de Medicamentos/métodos , Liberação Controlada de Fármacos , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Cinética , Testes de Sensibilidade Microbiana , Nanofibras/química , Nanofibras/ultraestrutura , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/crescimento & desenvolvimento
20.
Pathog Dis ; 75(7)2017 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-28859277

RESUMO

This study aimed to evaluate the association between haplotypes in the interleukin 8 (IL8) and IL4 genes previously associated to chronic periodontitis (CP) and the levels of Aggregatibacter actinomycetemcomitans (A.a.) in subgingival sites of patients with and without CP. Moreover, multifaceted evaluations were made to search associations among patients' genetic background with the A.a. levels and previous clinical/immunological/microbiological findings. Subgingival sites (n = 596) of 104 patients were divided into susceptible to CP by the IL8 haplotype ATC/TTC (IL8+); non-susceptible to CP by the IL8 AGT/TTC (IL8-); susceptible to CP by the IL4 TCI/CCI (IL4+); protection against CP by the IL4 TTD/CTI (IL4-). Subgingival biofilm samples from diseased and healthy sites of CP patients and from control sites of health patients were obtained for absolute quantification of A.a. by quantitative real-time polymerase chain reaction. For diseased sites, samples were collected before and 45 days after periodontal treatment. The IL4 but not the IL8 haplotypes were associated with levels of A.a. (in both periods). After periodontal treatment, higher levels of A.a. were found in subgingival sites of (IL4-) patients, and higher levels of IL-4 were associated with deeper probing pockets in these same patients. Significant correlations were found among genetic (patients carrying IL8 or IL4 haplotypes), microbiological and immunological data showing the interrelationship of different factors in the CP.


Assuntos
Aggregatibacter actinomycetemcomitans/genética , Biofilmes/crescimento & desenvolvimento , Periodontite Crônica/genética , Predisposição Genética para Doença , Interleucina-4/genética , Interleucina-8/genética , Polimorfismo Genético , Adulto , Aggregatibacter actinomycetemcomitans/crescimento & desenvolvimento , Aggregatibacter actinomycetemcomitans/isolamento & purificação , Aggregatibacter actinomycetemcomitans/patogenicidade , Carga Bacteriana , Periodontite Crônica/imunologia , Periodontite Crônica/microbiologia , Periodontite Crônica/terapia , Feminino , Expressão Gênica , Haplótipos , Humanos , Interleucina-4/imunologia , Interleucina-8/imunologia , Masculino , Pessoa de Meia-Idade , Análise Multivariada , RNA Ribossômico 16S/genética , Curetagem Subgengival
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