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1.
Rev. Odontol. Araçatuba (Impr.) ; 41(2): 52-57, maio-ago.2020. tab, ilus
Artigo em Português | LILACS (Américas), BBO | ID: biblio-1102702

RESUMO

Objetivo: avaliar a adesão bacteriana do Streptococcus mutans na superfície de uma resina composta do tipo incremento único submetida a diferentes protocolos de polimento. Materiais e métodos: foram realizadas 60 amostras nas quais foram divididas aleatoriamente em 6 grupos (n=10) de diferentes tratamentos de superfície. Cinco amostras de cada grupo foram separadas e submetidas ao estudo de adesão bacteriana, das quais duas foram analisadas pela microscopia eletrônica de varredura. Foram contabilizadas as unidades formadoras de colônias UFC/ml de modo manual e realizada a média e desvio padrão de cada grupo. De acordo com os resultados analisados através do teste de One Way ANOVA e comparações múltiplas de Tukey observou-se uma diferença estatisticamente significativa entre os grupos. Resultados: os valores de UFC/ mL variaram de 0 para o grupo American Burrs a 8,64 para o grupo Dhpro. Os grupos Jota e Dhpro não diferiram estatisticamente entre si (p=0,71), porém diferiram dos demais grupos avaliados (p=0,45). Os grupos American Burrs e o controle negativo não diferiram estatisticamente entre si (p>0.999) e diferiram dos demais grupos testados (p=0,20). O grupo de controle positivo diferiu estatisticamente dos outros grupos (p=0,02) assim como o grupo KG (p=0,01). Conclusão: Diante dos resultados obtidos, pode-se concluir que, a superfície da resina Bulk Fill One submetida a diferentes protocolos de polimento e mesmo sem ter passado por nenhum tratamento de superfície é passível de adesão bacteriana seja por contagem manual ou microscopia eletrônica de varredura(AU)


Objective: To evaluate the bacterial adhesion of Streptococcus mutans on the surface of a single increment composite resin submitted to different polishing protocols. Materials and methods: 60 samples were randomly divided into 6 groups (n = 10) of different surface treatments. Five samples from each group were separated and submitted to the bacterial adhesion study, two of which were analyzed by scanning electron microscopy. The UFC/ml colony forming units were accounted for manually and the mean and standard deviation of each group were performed. According to the results analyzed by the One Way ANOVA test and Tukey's multiple comparisons, a statistically significant difference was observed between the groups. Results: The values ranged from 0 for the American Burrs group to 8.64 for the Dhpro group. The Jota and Dhpro groups did not differ statistically (p = 0.71), but differed from the other groups evaluated (p = 0.45). The American Burrs and negative control groups did not differ statistically (p> 0.999) and differed from the other groups tested (p = 0.20). The positive control group differed statistically from the other groups (p = 0.02) as did the KG group (p = 0.01). Conclusion: It can be concluded that the surface of the Bulk Fill One resin submitted to different polishing protocols and even without any surface treatment is susceptible to bacterial adhesion either by manual counting or scanning electron microscopy(AU)


Assuntos
Streptococcus mutans , Aderência Bacteriana , Resinas Compostas , Resinas Sintéticas , Microscopia Eletrônica de Varredura
2.
Autops. Case Rep ; 9(3): e2019093, July-Sept. 2019. ilus
Artigo em Inglês | LILACS (Américas) | ID: biblio-1016685
3.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-764041

RESUMO

Streptococcus mutans is one of the important bacteria that forms dental biofilm and cause dental caries. Virulence genes in S. mutans can be classified into the genes involved in bacterial adhesion, extracellular polysaccharide formation, biofilm formation, sugar uptake and metabolism, acid tolerance, and regulation. The genes involved in bacterial adhesion are gbps (gbpA, gbpB, and gbpC) and spaP. The gbp genes encode glucan-binding protein (GBP) A, GBP B, and GBP C. The spaP gene encodes cell surface antigen, SpaP. The genes involved in extracellular polysaccharide formation are gtfs (gtfB, gtfC, and gtfD) and ftf, which encode glycosyltransferase (GTF) B, GTF C, and GTF D and fructosyltransferase, respectively. The genes involved in biofilm formation are smu630, relA, and comDE. The smu630 gene is important for biofilm formation. The relA and comDE genes contribute to quorum-sensing and biofilm formation. The genes involved in sugar uptake and metabolism are eno, ldh, and relA. The eno gene encodes bacterial enolase, which catalyzes the formation of phosphoenolpyruvate. The ldh gene encodes lactic acid dehydrogenase. The relA gene contributes to the regulation of the glucose phosphotransferase system. The genes related to acid tolerance are atpD, aguD, brpA, and relA. The atpD gene encodes F1F0-ATPase, a proton pump that discharges H⁺ from within the bacterium to the outside. The aguD gene encodes agmatine deiminase system and produces alkali to overcome acid stress. The genes involved in regulation are vicR, brpA, and relA.


Assuntos
Agmatina , Álcalis , Antígenos de Superfície , Bactérias , Aderência Bacteriana , Biofilmes , Cárie Dentária , Glucose , Ácido Láctico , Metabolismo , Oxirredutases , Fosfoenolpiruvato , Fosfopiruvato Hidratase , Bombas de Próton , Streptococcus mutans , Streptococcus , Virulência
4.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-766086

RESUMO

This article has been retracted at the request of the Editor-in-Chief, because the authors plagiarized a previously published paper that had appeared in: Int J Oral Maxillofac Implants, 26 (2011) 101–107. This article presented the same table and figures as the original study, and changed 2 of the tables to figures. This article reflects severe abuse of the scientific publishing system, and has therefore been retracted.


Assuntos
Aderência Bacteriana , Colo , Humanos , Titânio
5.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-742083

RESUMO

PURPOSE: The purpose of this study was to evaluate the effects of various protocols and systems for finishing and polishing monolithic zirconia on surface topography, phase transformation, and bacterial adhesion. MATERIALS AND METHODS: Three hundred monolithic zirconia specimens were fabricated and then treated with three finishing and polishing systems (Jota [JO], Meisinger [ME], and Edenta [ED]) using four surface treatment protocols: coarse finishing alone (C); coarse finishing and medium polishing (CM); coarse finishing and fine polishing (CF); and coarse finishing, medium polishing, and fine polishing (CMF). Surface roughness, crystal phase transformation, and bacterial adhesion were evaluated using atomic force microscopy, X-ray diffraction, and streptococcal biofilm formation assay, respectively. One-way and two-way analysis of variance with Tukey post hoc tests were used to analyze the results (α=.05). RESULTS: In this study, the surface treatment protocols and systems had significant effects on the resulting roughness. The CMF protocol produced the lowest roughness values, followed by CM and CF. Use of the JO system produced the lowest roughness values and the smallest biofilm mass, while the ME system produced the smallest partial transformation ratio. The ED group exhibited the highest roughness values, biofilm mass, and partial transformation ratio. CONCLUSION: Stepwise surface treatment of monolithic zirconia, combined with careful polishing system selection, is essential to obtaining optimal microstructural and biological surface results.


Assuntos
Aderência Bacteriana , Biofilmes , Protocolos Clínicos , Polimento Dentário , Microscopia de Força Atômica , Difração de Raios X
6.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-742070

RESUMO

PURPOSE: Surface finishing of a zirconia restoration is essential after clinical adjustment. Herein, we investigated the effects of a surface finishing protocol for monolithic zirconia on final roughness and bacterial adherence. MATERIALS AND METHODS: Forty-eight disk-shaped monolithic zirconia specimens were fabricated and divided into four groups (n = 12) based on initial surface treatment, finishing, and polishing protocols: diamond bur+polishing bur (DP group), diamond bur+stone grinding bur+polishing bur (DSP group), no diamond bur+polishing bur (NP group), and no diamond bur+stone grinding bur+polishing bur (NSP group). Initial and final surface roughness was measured with a profilometer, and shown using scanning electron microscope. Bacterial adhesion was evaluated by quantifying Streptococcus mutans in the biofilm. Kruskal-Wallis and Mann-Whitney U tests were used to compare results among groups, and two-way analysis of variance was used to evaluate the effects of grinding burs on final roughness (α=.05). RESULTS: The DP group had the highest final Ra value, followed by the DSP, NP, and NSP groups. Use of the stone grinding bur as a coarse-finishing step significantly decreased final Ra values when a diamond bur was used (P < .001). Omission of the stone grinding bur increased biofilm formation on specimen surfaces. Combining a stone grinding bur with silicone polishing burs produced the smallest final biofilm values, regardless of the use of a diamond bur in initial surface treatment. CONCLUSION: Coarse finishing of monolithic zirconia with a stone grinding bur significantly decreased final Ra values and bacterial biofilm formation when surfaces had been roughened by a diamond bur.


Assuntos
Aderência Bacteriana , Biofilmes , Instrumentos Odontológicos , Polimento Dentário , Diamante , Silício , Silicones , Streptococcus mutans
7.
Chinese Medical Journal ; (24): 446-453, 2019.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-774833

RESUMO

BACKGROUND@#Adhesion, biofilm formation, yeast-hyphal transition, secretion of enzymes, and hemolytic activity are all considered important factors in Candida tropicalis infection. However, DNA sequence data for this pathogen are limited. In this study, the polymorphism and heterogeneity of genes agglutinin-like sequences (ALS)2, Lipase (LIP)1, LIP4, and secretory aspartyl proteinase tropicalis (SAPT)1-4 as well as the relationship between phenotype and genotype were analyzed.@*METHODS@#This study started in August 2013, and ended in July 2017. The complete length of ALS2, LIP1, LIP4, and SAPT1-4 of 68 clinical C. tropicalis isolates was sequenced. Single nucleotide polymorphisms (SNPs) as well as insertions and deletions (indels) were identified within these genes. In addition, phenotypic characteristics of the virulent factors, including adhesion and the secretion of aspartyl proteinases and phospholipases, were determined.@*RESULTS@#There were 73, 24, 17, 16, 13, and 180 SNPs in the genes LIP1, LIP4, SAPT1, SAPT2, SAPT3, and SAPT4, respectively. Furthermore, 209 SNPs were identified in total for the gene ALS2. Interestingly, large fragment deletions and insertions were also found in ALS2. Isolate FXCT 01 obtained from blood had deletions on all 4 sites and showed the lowest adhesion ability on the polymethylpentene surface. In addition, isolates with deletions in the regions 1697 to 1925 and 2073 to 2272 bp displayed relatively low abilities for adhesion and biofilm formation, and this phenotype correlated with the deletions found in ALS2. LIP1, SAPT4, and ALS2 displayed great heterogeneity among the isolates. Large deletions found in gene ALS2 appeared to be associated with the low ability of adhesion and biofilm formation of C. tropicalis.@*CONCLUSION@#This study might be useful for deeper explorations of gene function and studying the virulent mechanisms of C. tropicalis.


Assuntos
Aderência Bacteriana , Biofilmes , Candida tropicalis , Genética , Virulência , Lipase , Genética , Polimorfismo de Nucleotídeo Único , Virulência , Genética
8.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-774131

RESUMO

Despite the continuous improvement in perioperative use of antibiotics and aseptic techniques, the incidence of infection continues to rise as the need for surgery increasing and brings great challenges to orthopedic surgery. The rough or porous structure of the prosthesis provides an excellent place for bacterial adhesion, proliferation and biofilm formation, which is the main cause of infection. Traditional antibiotic therapy and surgical debridement are difficult to determine whether the infected focus have been removed completely and whether the infection will recur. In recent years, nanotechnology has shown obvious advantages in biomaterials and drug delivery. Nano drug carriers can effectively achieve local antimicrobial therapy, prevent surgical infection by local sustained drug release or intelligent controlled drug release under specific stimuli, and reduce the toxic side effects of drugs. The unique advantages of nanotechnology provide new ideas and options for the prevention and treatment of periprosthetic infection. At present, the application of nano-technology in the prevention and treatment of infection can be divided into the addition of nano-drug-loaded materials to prosthesis materials, the construction of drug-loaded nano-coatings on the surface of prosthesis, the perfusable nano-antimicrobial drug carriers, and the stimulation-responsive drug controlled release system. This article reviews the methods of infection prevention and treatment in orthopaedic surgery, especially the research status of nanotechnology in the prevention and treatment of periprosthetic infection.


Assuntos
Anti-Infecciosos , Aderência Bacteriana , Portadores de Fármacos , Humanos , Nanotecnologia , Ortopedia , Infecções Relacionadas à Prótese
9.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-772645

RESUMO

OBJECTIVE@#To evaluate the process characterization of graphene oxide loaded on pure titanium surface and effect on the biological properties of Staphylococcus aureus and osteoblasts.@*METHODS@#Graphene oxide at four concentrations (20, 50, 80, and 100 µg·mL⁻¹) was loaded on the pure titanium surface via electroplating, and the morphology, properties, and hydrophilic properties were measured with a field emission scanning electron microscope, micro Raman spectrometer, and contact angle tester, respectively. In addition, Staphylococcus aureus and osteoblasts were used as models and cultured with pure titanium-graphene oxide. Then, field-emission scanning electron microscopy and laser confocal microscopy were utilized to observe the changes in the amount of bacteria and osteoblast morphology and structure, respectively.@*RESULTS@#Graphene oxide at the four concentrations was successfully loaded on pure titanium surface via electroplating. It improved the hydrophilic properties of pure titanium surface, which benefitted the adhesion and growth of Staphylococcus aureus and changed the morphology and structure of the osteoblasts.@*CONCLUSIONS@#The pure titanium-graphene oxide composite has no antibacterial properties and has good biocompatibility.


Assuntos
Aderência Bacteriana , Adesão Celular , Grafite , Microscopia Eletrônica de Varredura , Osteoblastos , Óxidos , Propriedades de Superfície , Titânio
10.
Rev. odontol. UNESP (Online) ; 48: e20190029, 2019. graf, ilus
Artigo em Inglês | LILACS (Américas), BBO | ID: biblio-1020751

RESUMO

Abstract Introduction Streptococcus salivarius is a dominant oral species and the best suitable candidate for probiotic of the oral cavity. Since Streptococcus salivarius is able to produce bacteriocins against Streptococcus pyogenes interest has been focused on the use of it as a probiotic to avoid sore throats by Streptococcus pyogenes. Objective This study is for selecting Streptococcus salivarius strains for potential use as probiotics for the oral mucosa, that is, production of bacteriocin against Streptococcus pyogenes and the ability to bind to KB cells. Material and method Tongue material from 45 students was collected and seeded on Mitis Salivarius Agar plaques. The strains were tested by the production of bacteriocin-like substances (BLIS) against S. pyogenes, biochemically and PCR for identification of S. salivarius. The best strains were tested for adherence to KB cells. Briefly, S. salivarius strains were cultured in broth, washed and suspended at 108cells/ml. KB cells were inoculated into plaques, washed and incubated with the bacteria, for adhesion. These were washed for lysis of the KB cells and release bacteria for determination of CFU. Result The bacteriocin test showed that 133 strains presented inhibition of S. pyogenes. The samples tested for adhesion to KB cells, presented different profiles and only three strains presenting high adhesion capacity. Conclusion The selection of strains of Streptococcus salivarius with high inhibitory activity against Streptococcus pyogenes, as well as adherence to KB cells leads us to the next future step, that is, to use the best strains for in vivo colonization tests


Resumo Introdução Streptococcus salivarius é uma espécie dominante na cavidade bucal e tem sido indicada como um ótimo candidato para uso como probiótico. Visto que a espécie Streptococcus salivarius é capaz de produzir bacteriocinas contra Streptococcus pyogenes, desenvolveu-se interesse no uso desse microrganismo como probiótico, para evitar amigdalites causadas por Streptococcus pyogenes. Objetivo A pesquisa em questão tem o objetivo de selecionar cepas de Streptococcus salivarius para seu uso potencial como probióticos na cavidade bucal, ou seja, produção de bacteriocinas contra Streptococcus pyogenes e habilidade de aderência à células KB. Material e método Coletou-se material de língua de 45 estudantes e semeou-se em placas de ágar Mitis Salivarius. As amostras foram testadas para verificar a produção de substâncias semelhantes à bacteriocina (BLIS) contra S. pyogenes, bioquimicamente e através de PCR para identificação de S. salivarius. As melhores cepas foram testadas quanto aderência à células KB. Resumidamente, as cepas de S. salivarius foram cultivadas em caldo, lavadas e suspensas à correspondência de 108 cels/ml. As células KB foram inoculadas em placas, lavadas e incubadas com as bactérias, para adesão. Estas foram lavadas para lise das células KB e liberação das bactérias para determinação de UFC. Resultado O teste de bacteriocina, mostrou que 133 cepas apresentaram atividade inibitória contra Streptococcus pyogenes. As cepas testadas para aderência à células KB, apresentaram diferentes perfis e somente três com alta capacidade de adesão. Conclusão: A seleção de cepas de Streptococcus salivarius com alta atividade inibitória contra Streptococcus pyogenes, bem como aderência a células KB, pode nos levar ao próximo passo, ou seja, o uso das melhores cepas para o estudo de colonização in vivo.


Assuntos
Bacteriocinas , Aderência Bacteriana , Células KB , Probióticos/uso terapêutico , Streptococcus salivarius , Streptococcus pyogenes , Tonsilite/prevenção & controle , Antibiose
11.
São José dos Campos; s.n; 2019. 76 p. il., graf., tab..
Tese em Português | LILACS (Américas), BBO | ID: biblio-999012

RESUMO

O objetivo deste estudo foi avaliar se há alteração no comportamento mecânico e na aderência microbiológica da cerâmica à base de dissilicato de lítio com a técnica de pigmentação extrínseca aplicada, após ser submetida a diferentes condições experimentais. Foram confeccionadas 160 amostras, divididas em grupos com e sem pigmentação (n=80). Destes, cada grupo foi subdividido em Controle, Desgate, Biodegradação e Desgaste com Biodegradação (n=20).15 amostras de cada subgrupo foram submetidas ao teste de resistência à flexão e 5 para o teste de aderência microbiológica. As amostras passaram anteriormente por testes complementares para caracterização da superfície (rugosidade, perfilometria volumétrica e microscopia eletrônica de varredura (MEV)). Os resultados foram submetidos a análise estatística descritiva (média e desvio padrão) e inferencial, mediante o teste paramétrico de análise de variância (ANOVA) dois fatores e teste de Tukey ( = 0,05). O fator pigmentação extrínseca influenciou negativamente no comportamento mecânico da cerâmica, apresentando significância estatística (p = 0,000), assim como a interação entre o tipo de condição experimental e a pigmentação (p = 0,020). Entretanto, na aderência microbiológica, foi a condição experimental que influenciou negativamente no comportamento microbiológico (p = 0,000), assim como a interação entre a condição experimental e a pigmentação (p = 0,000). Nas análises complementares, observou-se que a interação entre os fatores aumentou a rugosidade superfial (p = 0,000) e aumentou o volume perdido pelo desgatse (p = 0,040). As microscopias da superficie mostram as características de cada grupo, mostrando as diferenças entre as condições experimentais com e sem pigmentação extrínseca. E as microscopias da aderência microbiológica ilustram e confirmam os resultados obtidos no teste estatístico. Concluiu-se que a pigmentação extrínseca altera as propriedades mecânicas da cerâmica de dissilicato de lítio, reduzindo a resistência à flexão e aumentando a rugosidade superficial e o desgaste. Porém, a aderência microbiológica foi aumentada pela condição experimental. Entretanto, a interação entre os fatores contribuiu para esse aumento e para agravar a alteração nas propriedades mecânicas(AU)


The objective of this study was to evaluate the mechanical and microbiological behavior of the ceramics based on lithium disilicate with extrinsic characterization. For this, 160 discs were made, divided into two large groups, with extrinsec characterization and without, after which each was divided into four groups (n = 20): Control, Wear, Biodegradation and Biodegradation with Wear. Fifteen samples from each group were submitted to the flexural strength test and 5 submitted to the microbiological adherence test. Prior to the destructive test of flexural strength, the representative samples of each group underwent complementary tests for surface characterization. The results were submitted to descriptive statistical analysis (mean and standard deviation) and inferential, using the parametric analysis of variance (ANOVA) two way and Tukey test ( = 0,05). The extrinsec characterization factor influenced the mechanical behavior of the ceramic, presenting statistical significance (p = 0.000), as well as the interaction between the type of experimental condition and the extrinsec characterization (p = 0.020). However, in the microbiological adherence, it was the experimental condition that influenced the microbiological behavior (p = 0.000), as well as the interaction between the experimental condition and the extrinsec characterization (p = 0.000). It was concluded that the makeup influenced the mechanical behavior of the ceramic, and the experimental condition influenced the microbiological adherence. The interaction between the factors influenced both the mechanical behavior and the microbiological adherence(AU)


Assuntos
Humanos , Cerâmicas Modificadas Organicamente/efeitos adversos , Aderência Bacteriana/imunologia , Pigmentação/imunologia
12.
J. appl. oral sci ; 27: e20180262, 2019. tab
Artigo em Inglês | LILACS (Américas), BBO | ID: biblio-1019969

RESUMO

Abstract The incorporation of antimicrobials in the composites as an attempt to reduce bacterial adhesion without jeopardizing mechanical properties is a challenge for Dentistry. Objective: To evaluate the bacterial adhesion and physical properties of a composite containing the methacrylate triclosan- derivative monomer (TM). Methodology: TM was synthesized and added to an experimental composite. Samples were divided into two groups: Control and TM (13.4 wt%). Antibacterial Activity: Three specimens of each material were prepared and placed on bacterial suspensions of Streptococcus mutans for 1, 5 and 10 days. After these periods the counting of the colonies (log10) was performed. Assays was performed in triplicate. Physical Properties: Three-body Abrasion (TBA): Ten specimens of each material were prepared and stored at 37°C/24 h. The surface roughness (Ra) and hardness (KHN) were analyzed. Next, the specimens were submitted to abrasive wear (30,000 cycles) and re-evaluated for Ra and KHN; Sorption/solubility (SS): cylindrical specimens (n=10) were prepared and weighted. The specimens were immersed in deionized water for 7 days at 37°C and then their weight was verified again. SS were calculated using accepted formulas; Diametral tensile strength (DTS): specimens (n=10) underwent test performed in an Instron universal testing machine at a crosshead speed of 1 mm/min. Data were submitted to appropriate statistical tests according to data distribution and assay (p<0.05). Results: Bacterial Adhesion: TM showed a significant reduction on biofilm accumulation in the evaluated periods: 1 day (1.537±0.146); 5 days (2.183±0.138) and 10 days (4.469±0.155) when compared with Control: 1 day (4.954±0.249); 5 days (5.498±0.257) and 10 days (6.306±0.287). Physical Properties: For TBA, SS and DTS no significant difference was found between groups Control and TM. The incorporation of methacrylate triclosan-based monomer in the experimental composite reduce bacterial adhesion of S. mutans and did not affect important polymer properties.


Assuntos
Triclosan/química , Resinas Compostas/química , Metacrilatos/química , Antibacterianos/química , Valores de Referência , Solubilidade , Streptococcus mutans/efeitos dos fármacos , Propriedades de Superfície , Resistência à Tração , Fatores de Tempo , Escovação Dentária , Triclosan/farmacologia , Aderência Bacteriana/efeitos dos fármacos , Teste de Materiais , Contagem de Colônia Microbiana , Reprodutibilidade dos Testes , Resinas Compostas/farmacologia , Testes de Dureza , Metacrilatos/farmacologia , Antibacterianos/farmacologia
13.
Braz. j. microbiol ; 49(2): 310-319, Apr.-June 2018. tab, graf
Artigo em Inglês | LILACS (Américas) | ID: biblio-889225

RESUMO

Abstract The aim of this study was evaluated the biofilm formation by Staphylococcus aureus 4E and Salmonella spp. under mono and dual-species biofilms, onto stainless steel 316 (SS) and polypropylene B (PP), and their sensitivity to cetrimonium bromide, peracetic acid and sodium hypochlorite. The biofilms were developed by immersion of the surfaces in TSB by 10 d at 37 °C. The results showed that in monospecies biofilms the type of surface not affected the cellular density (p > 0.05). However, in dual-species biofilms on PP the adhesion of Salmonella spp. was favored, 7.61 ± 0.13 Log10 CFU/cm2, compared with monospecies biofilms onto the same surface, 5.91 ± 0.44 Log10 CFU/cm2 (p < 0.05). The mono and dual-species biofilms were subjected to disinfection treatments; and the most effective disinfectant was peracetic acid (3500 ppm), reducing by more than 5 Log10 CFU/cm2, while the least effective was cetrimonium bromide. In addition, S. aureus 4E and Salmonella spp. were more resistant to the disinfectants in mono than in dual-species biofilms (p < 0.05). Therefore, the interspecies interactions between S. aureus 4E and Salmonella spp. had a negative effect on the antimicrobial resistance of each microorganism, compared with the monospecies biofilms.


Assuntos
Biofilmes/efeitos dos fármacos , Compostos de Cetrimônio/farmacologia , Desinfetantes/farmacologia , Ácido Peracético/farmacologia , Salmonella/efeitos dos fármacos , Hipoclorito de Sódio/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Aderência Bacteriana/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Contagem de Colônia Microbiana , Meios de Cultura/química , Microbiologia Ambiental , Interações Microbianas , Viabilidade Microbiana/efeitos dos fármacos , Polipropilenos , Salmonella/crescimento & desenvolvimento , Aço Inoxidável , Staphylococcus aureus/crescimento & desenvolvimento , Temperatura , Tempo
14.
An. acad. bras. ciênc ; 90(1): 73-84, Mar. 2018. tab
Artigo em Inglês | LILACS (Américas) | ID: biblio-886885

RESUMO

ABSTRACT The adhesion ability of bacteria to abiotic surfaces has important implications in food industries, because these organisms can survive for long periods through the biofilm formation. They can be transferred from one place to another in the industry causing contamination of the food processing environment. In this study, the antibacterial and antibiofilm activities of the antimicrobial peptide P34, characterized as a bacteriocin-like substance (BLS P34) were tested against planktonic and sessile cells of Staphylococcus aureus and Enterococcus faecalis isolated from foods. The BLS P34 showed inhibitory effect against all planktonic cells of E. faecalis. The inhibition of biofilm formation and the eradication of pre-formed biofilm were evaluated with the crystal violet assay and with the reduction of 3-bromide [4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium. The BLS P34 promoted a reduction of percentage of adhered microbial cells on the surface, not being able to perform the complete elimination of biofilm formation. The metabolic activity of S. aureus biofilms decreased considerably between 41-95%. However, E. faecalis cells showed up metabolically stimulated. The BLS P34 has the potential antibiofilm for the species S. aureus. Studies suggest more detailed approaches to a better understanding of the interactions between the antimicrobial and bacterial cells within the biofilm structure.


Assuntos
Animais , Oligopeptídeos/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Bacteriocinas/farmacologia , Enterococcus faecalis/efeitos dos fármacos , Biofilmes/efeitos dos fármacos , Antibacterianos/farmacologia , Bacillus/isolamento & purificação , Bacillus/metabolismo , Bacteriocinas/isolamento & purificação , Aderência Bacteriana/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Análise de Variância
15.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-766048

RESUMO

PURPOSE: The goal of this study was to develop and validate a standardized in vitro pathogenic biofilm attached onto saliva-coated surfaces. METHODS: Fusobacterium nucleatum (F. nucleatum) and Porphyromonas gingivalis (P. gingivalis) strains were grown under anaerobic conditions as single species and in dual-species cultures. Initially, the bacterial biomass was evaluated at 24 and 48 hours to determine the optimal timing for the adhesion phase onto saliva-coated polystyrene surfaces. Thereafter, biofilm development was assessed over time by crystal violet staining and scanning electron microscopy. RESULTS: The data showed no significant difference in the overall biomass after 48 hours for P. gingivalis in single- and dual-species conditions. After adhesion, P. gingivalis in single- and dual-species biofilms accumulated a substantially higher biomass after 7 days of incubation than after 3 days, but no significant difference was found between 5 and 7 days. Although the biomass of the F. nucleatum biofilm was higher at 3 days, no difference was found at 3, 5, or 7 days of incubation. CONCLUSIONS: Polystyrene substrates from well plates work as a standard surface and provide reproducible results for in vitro biofilm models. Our biofilm model could serve as a reference point for studies investigating biofilms on different surfaces.


Assuntos
Aderência Bacteriana , Biofilmes , Biomassa , Fusobacterium nucleatum , Fusobacterium , Violeta Genciana , Técnicas In Vitro , Microscopia Eletrônica de Varredura , Poliestirenos , Porphyromonas gingivalis , Porphyromonas
16.
Artigo em Coreano | WPRIM (Pacífico Ocidental) | ID: wpr-717287

RESUMO

Increasing demands for zirconia material in clinics, assessment of biocompatibility of zirconia is essential. In this article, a review of in vitro studies of zirconia compatibility was performed. Zirconia showed great biocompatibility at in vitro studies with various cell lines such as fibroblasts, osteoblasts, and lymphocytes. Many studies reported that zirconia caused no cytotoxicity or mutation. Zirconia also showed less bacterial adhesion. There were no adverse effects except for small reduced strength with in vitro study mimicking long-term exposure of body fluid. According to the study with ostoblast-like cells, zirconia could regulate genes of immunity, molecular transport, and cell cycle. Such gene regulating was considered as one of the reasons of zirconia biocompatibility. With biocompatibility of zirconia powders, in vitro studies had controversial conclusions. It seems that zirconia powders might have cytotoxicity


Assuntos
Aderência Bacteriana , Líquidos Corporais , Ciclo Celular , Linhagem Celular , Fibroblastos , Técnicas In Vitro , Linfócitos , Osteoblastos , Pós
17.
Artigo em Coreano | WPRIM (Pacífico Ocidental) | ID: wpr-714097

RESUMO

The purpose of our study is to compare the adhesion and biofilm formation abilities of isolates from water discharged from dental unit waterlines (DUWLs). Bacteria were isolated from a total of 15 DUWLs. Twelve isolates were selected for the experiment. To confirm the adhesion ability of the isolates, each isolate was attached to a glass coverslip using a 12-well plate. Plates were incubated at 26℃ for 7 days, and the degree of adhesion of each isolate was scored. To verify the biofilm formation ability of each isolate, biofilms were allowed to form on a 96-well polystyrene flat-bottom microtiter plate. The biofilm accumulations of all isolates formed at 26℃ for 7 days were identified and compared. A total of 56 strains were isolated from 15 water samples including 12 genera and 31 species. Of the 56 isolates, 12 isolates were selected according to the genus and used in the experiment. Sphingomonas echinoides, Methylobacterium aquaticum, and Cupriavidus pauculus had the highest adhesion ability scores of +3 among 12 isolates. Among these three isolates, the biofilm accumulation of C. pauculus was the highest and that of S. echinoides was the third-most abundant. The lowest biofilm accumulations were identified in Microbacterium testaceum and M. aquaticum. Most isolates with high adhesion ability also exhibited high biofilm formation ability. Analysis of adhesion and biofilm formation of the isolates from DUWLs can provide useful information to understand the mechanism of DUWL biofilm formation and development.


Assuntos
Bactérias , Aderência Bacteriana , Biofilmes , Cupriavidus , Vidro , Controle de Infecções Dentárias , Methylobacterium , Poliestirenos , Sphingomonas , Água , Microbiologia da Água
18.
Braz. j. oral sci ; 17: e18135, 2018. ilus
Artigo em Inglês | LILACS (Américas), BBO | ID: biblio-963974

RESUMO

Aim: This study evaluated the surface topography and bacterial adhesion of a hybrid ceramic and a nano ceramic resin composite after different surface finishes. Methods: Hybrid ceramic (Vita Enamic, VITA - EN) and nano ceramic resin composite (Lava Ultimate, 3M/ESPE - LV) blocks of 12 x 14 x 18 mm were cut into 1 mm slices. Each slice was divided into four specimens (6 x 7 mm) that were randomly allocated into 4 groups (n=8) according to the surface finishing: CTL - without surface finish (control); DB - wear with a diamond bur; VT - polishing system for hybrid ceramic (VITA); and DD - polishing system for ceramics (Dedeco). The specimens were analyzed regarding surface roughness parameters (Ra, Rz, Rq), sterilized and subjected to bacterial adhesion. Representative specimens from each group were observed by SEM and Confocal Laser Scanning Microscopy. Data were submitted to two-way ANOVA and Tukey's test (α=0.05). Results: EN had lower surface roughness and bacterial adhesion than LV (p<0.05), regardless of the surface finish. The highest values for all roughness parameters was observed in LVDB group, differing from the other groups, which were not significantly different. Smaller bacterial adhesion values (CFU/mL) were observed for ENDD and ENVT, which differed significantly from the other groups, except ENCTL. For LV groups there was no significant difference between the different surface finishes (p>0.05). The type of material and surface finish system significantly interfered with surface roughness parameters and bacterial adhesion. The hybrid ceramic performed better after polishing than the nano-ceramic resin. Conclusion: An adequate finishing/polishing technique should always be performed after any kind of adjustment to indirect restorations made with these materials tested


Assuntos
Aderência Bacteriana , Cerâmica , Desenho Assistido por Computador , Resinas Compostas , Polimento Dentário
19.
Braz. j. microbiol ; 48(4): 764-768, Oct.-Dec. 2017. graf
Artigo em Inglês | LILACS (Américas) | ID: biblio-889184

RESUMO

ABSTRACT Clostridium perfringens is the causative agent for necrotic enteritis. It secretes the major virulence factors, and α- and NetB-toxins that are responsible for intestinal lesions. The TpeL toxin affects cell morphology by producing myonecrosis, but its role in the pathogenesis of necrotic enteritis is unclear. In this study, the presence of netB and tpeL genes in C. perfringens type A strains isolated from chickens with necrotic enteritis, their cytotoxic effects and role in adhesion and invasion of epithelial cells were evaluated. Six (27.3%) of the 22 C. perfringens type A strains were harboring the tpeL gene and produced morphological alterations in Vero cells after 6 h of incubation. Strains tpeL (-) induced strong cell rounding after 6 h of incubation and produced cell enlargement. None of the 22 strains harbored netB gene. All the six tpeL (+) gene strains were able to adhere to HEp-2 cells; however, only four of them (66.6%) were invasive. Thus, these results suggest that the presence of tpeL gene or TpeL toxin might be required for the adherence of bacteria to HEp-2 cells; however, it could not have any role in the invasion process.


Assuntos
Humanos , Animais , Doenças das Aves Domésticas/microbiologia , Aderência Bacteriana , Infecções por Clostridium/microbiologia , Infecções por Clostridium/veterinária , Clostridium perfringens/fisiologia , Células Epiteliais/microbiologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Células Vero , Chlorocebus aethiops , Galinhas , Clostridium perfringens/isolamento & purificação , Clostridium perfringens/genética
20.
Electron. j. biotechnol ; 29: 13-21, sept. 2017. ilus, tab, graf
Artigo em Inglês | LILACS (Américas) | ID: biblio-1017057

RESUMO

Background: The past years have witnessed a growing number of researches in biofilm forming communities due to their environmental and maritime industrial implications. To gain a better understanding of the early bacterial biofilm community, microfiber nets were used as artificial substrates and incubated for a period of 24 h in Mauritian coastal waters. Next-generation sequencing technologies were employed as a tool for identification of early bacterial communities. Different genes associated with quorum sensing and cell motility were further investigated. Results: Proteobacteria were identified as the predominant bacterial microorganisms in the biofilm within the 24 h incubation, of which members affiliated to Gammaproteobacteria, Alphaproteobacteria and Betaproteobacteria were among the most abundant classes. The biofilm community patterns were also driven by phyla such as Firmicutes, Bacteroidetes, Chloroflexi, Actinobacteria and Verrucomicrobia. The functional analysis based on KEGG classification indicated high activities in carbohydrate, lipid and amino acids metabolism. Different genes encoding for luxI, lasI, agrC, flhA, cheA and cheB showed the involvement of microbial members in quorum sensing and cell motility. Conclusion: This study provides both an insight on the early bacterial biofilm forming community and the genes involved in quorum sensing and bacterial cell motility.


Assuntos
Água do Mar/microbiologia , Bactérias/crescimento & desenvolvimento , Bactérias/genética , Fenômenos Fisiológicos Bacterianos , Bactérias/isolamento & purificação , Bactérias/classificação , Aderência Bacteriana , Movimento Celular , Biofilmes , Biodiversidade , Percepção de Quorum , Incrustação Biológica , Metagenômica , Sequenciamento de Nucleotídeos em Larga Escala , Maurício
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