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1.
Rev. Odontol. Araçatuba (Impr.) ; 41(2): 52-57, maio-ago.2020. tab, ilus
Artigo em Português | LILACS, BBO - Odontologia | 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 | ID: biblio-1016685
3.
São José dos Campos; s.n; 2019. 76 p. il., graf., tab..
Tese em Português | LILACS, BBO - Odontologia | 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
4.
Braz. j. microbiol ; 49(2): 310-319, Apr.-June 2018. tab, graf
Artigo em Inglês | LILACS | 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
5.
An. acad. bras. ciênc ; 90(1): 73-84, Mar. 2018. tab
Artigo em Inglês | LILACS | 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
6.
Braz. j. oral sci ; 17: e18135, 2018. ilus
Artigo em Inglês | LILACS, BBO - Odontologia | 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
7.
Braz. j. microbiol ; 48(4): 764-768, Oct.-Dec. 2017. graf
Artigo em Inglês | LILACS | 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
8.
Electron. j. biotechnol ; 29: 13-21, sept. 2017. ilus, tab, graf
Artigo em Inglês | LILACS | 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
9.
J. appl. oral sci ; 25(4): 436-441, July-Aug. 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-893638

RESUMO

Abstract Bacterial endotoxin (LPS) adhesion to orthodontic brackets is a known contributing factor to inflammation of the adjacent gingival tissues. Objective The aim of this study was to assess whether LPS adheres to orthodontic adhesive systems, comparing two commercial brands. Material and Methods Forty specimens were fabricated from Transbond XT and Light Bond composite and bonding agent components (n=10/component), then contaminated by immersion in a bacterial endotoxin solution. Contaminated and non-contaminated acrylic resin samples were used as positive and negative control groups, respectively. LPS quantification was performed by the Limulus Amebocyte Lysate QCL-1000™ test. Data obtained were scored and subjected to the Chi-square test using a significance level of 5%. Results There was endotoxin adhesion to all materials (p<0.05). No statistically significant difference was found between composites/bonding agents and acrylic resin (p>0.05). There was no significant difference (p>0.05) among commercial brands. Affinity of endotoxin was significantly greater for the bonding agents (p=0.0025). Conclusions LPS adhered to both orthodontic adhesive systems. Regardless of the brand, the endotoxin had higher affinity for the bonding agents than for the composites. There is no previous study assessing the affinity of LPS for orthodontic adhesive systems. This study revealed that LPS adheres to orthodontic adhesive systems. Therefore, additional care is recommended to orthodontic applications of these materials.


Assuntos
Aderência Bacteriana/fisiologia , Lipopolissacarídeos/fisiologia , Resinas Compostas/química , Cimentos de Resina/química , Escherichia coli , Valores de Referência , Teste de Materiais , Ensaio de Imunoadsorção Enzimática , Lipopolissacarídeos/isolamento & purificação
10.
Braz. j. microbiol ; 48(3): 587-591, July-Sept. 2017. graf
Artigo em Inglês | LILACS | ID: biblio-889137

RESUMO

Abstract The pathogenic bacterium Listeria monocytogenes can persist in food processing plants for many years, even when appropriate hygienic measures are in place, with potential for contaminating ready-to-eat products and, its ability to form biofilms on abiotic surfaces certainly contributes for the environmental persistence. In this research, L. monocytogenes was grown in biofilms up 8 days attached to stainless steel and glass surfaces, contributing for advancing the knowledge on architecture of mature biofilms, since many literature studies carried out on this topic considered only early stages of cell adhesion. In this study, biofilm populations of two strains of L. monocytogenes (serotypes 1/2a and 4b) on stainless steel coupons and glass were examined using regular fluorescence microscopy, confocal laser scanning microscopy and classic culture method. The biofilms formed were not very dense and microscopic observations revealed uneven biofilm structures, with presence of exopolymeric matrix surrounding single cells, small aggregates and microcolonies, in a honeycomb-like arrangement. Moreover, planktonic population of L. monocytogenes (present in broth media covering the abiotic surface) remained stable throughout the incubation time, which indicates an efficient dispersal mechanism, since the culture medium was replaced daily. In conclusion, even if these strains of L. monocytogenes were not able to form thick multilayer biofilms, it was noticeable their high persistence on abiotic surfaces, reinforcing the need to focus on measures to avoid biofilm formation, instead of trying to eradicate mature biofilms.


Assuntos
Aço Inoxidável/química , Biofilmes , Manipulação de Alimentos/instrumentação , Vidro/química , Listeria monocytogenes/crescimento & desenvolvimento , Aderência Bacteriana , Listeria monocytogenes/isolamento & purificação , Listeria monocytogenes/fisiologia
11.
Braz. dent. j ; 28(3): 317-323, May-June 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-888643

RESUMO

Abstract The aim of this study was to evaluate the surface free energy (SFE), wetting and surface properties as well as antimicrobial, adhesion and biocompatibility properties of diamond-like carbon (DLC)-coated surfaces. In addition, the leakage of Escherichia coli through the abutment-dental implant interface was also calculated. SFE was calculated from contact angle values; R a was measured before and after DLC coating. Antimicrobial and adhesion properties against E. coli and cytotoxicity of DLC with human keratinocytes (HaCaT) were evaluated. Further, the ability of DLC-coated surfaces to prevent the migration of E. coli into the external hexagonal implant interface was also evaluated. A sterile technique was used for the semi-quantitative polymerase chain reaction (semi-quantitative PCR). The surfaces showed slight decreases in cell viability (p<0.05), while the SFE, R a, bacterial adhesion, antimicrobial, and bacterial infiltration tests showed no statistically significant differences (p>0.05). It was concluded that DLC was shown to be a biocompatible material with mild cytotoxicity that did not show changes in R a, SFE, bacterial adhesion or antimicrobial properties and did not inhibit the infiltration of E. coli into the abutment-dental implant interface.


Resumo O objetivo deste trabalho foi avaliar a energia livre de superfície (ELS), molhabilidade e propriedades de superfície assim como propriedades antimicrobianas, de adesão e biocompatibilidade de superfícies recobertas com Diamond-Like Carbon (DLC). Além disso, investigou-se a infiltração de Escherichia coli por meio da interface abutment-implante dentário. ELS foi calculada a partir dos valores de ângulo de contato; Ra foi medida antes e depois do revestimento com DLC. Foram avaliadas propriedades antimicrobianas e de adesão contra E. coli e citotoxicidade do DLC utilizando queratinócitos humanos (HaCaT). Além disso, também avaliamos a capacidade para impedir a migração de E. coli na interface do implante hexágono externo. Uma técnica estéril foi utilizada para a reação em cadeia da polimerase semi-quantitativa (PCR semi-quantitativo). As superfícies mostraram uma ligeira diminuição da viabilidade celular (p<0,05), enquanto a ELS, R a , adesão bacteriana, testes antimicrobianos e de infiltração não apresentaram diferenças estatisticamente significativas (p>0,05). Concluiu-se que o DLC demonstrou ser um material biocompatível levemente citotóxico que não mostra alterações na Ra , ELS, adesão bacteriana ou propriedades antimicrobianas e não inibiu a infiltração de E. coli na interface abutment-implante dentário.


Assuntos
Humanos , Biofilmes , Carbono , Materiais Revestidos Biocompatíveis , Dente Suporte , Implantes Dentários , Diamante , Antibacterianos , Aderência Bacteriana , Linhagem Celular , Escherichia coli/isolamento & purificação , Escherichia coli/fisiologia , Queratinócitos/citologia , Reação em Cadeia da Polimerase , Propriedades de Superfície
12.
NOVA publ. cient ; 15(27): 67-75, ene.-jun. 2017. graf
Artigo em Espanhol | LILACS, COLNAL | ID: biblio-895071

RESUMO

Resumen Los factores de adhesión son determinantes de virulencia que se expresan en microorganismos que tienen la capacidad de formar biopelícula, contribuyendo a la gravedad de infecciones intrahospitalarias. Dentro de estos componentes de la superficie microbiana que reconocen moléculas de adhesión de matriz conocidas como MSCRAMMs, se incluyen el factor de unión a fibronectina A y B, (FnbA y B) factor de aglutinación A y B (ClfA y B) y factor de unión a fibrinógeno (Fib), que se han descrito en Staphylococcus aureus y reaccionan con proteínas de la matriz extracelular humana. El objetivo de este estudio fue determinar la presencia de estos factores de adhesión relacionados con la formación de biopelicula en Staphylococcus. Método. Se caracterizaron fenotípica y genotípicamente 30 aislamientos clínicos de Staphylococcus aureus y Staphylococcus epidermidis, provenientes de pacientes inmunocomprometidos en tres instituciones hospitalarias de Bogotá. La producción de Biopelícula se determinó mediante Rojo Congo y Cristal violeta y mediante PCR convencional y múltiplex se amplificaron los genes FnbA y B, ClfA y B y Fib, así como los genes del operón ica ADBC. Resultados. Todos los aislamientos clínicos fueron positivos genotípica y fenotípicamente para la producción de Biopelícula, encontrándose la presencia del operón completo en el 88.9%, los factores ClfA y ClfB en un 70%; Fib en un 60%, FnbB en un 23% y FnbA en el 17%. Conclusiones. En este estudio se evidenció la presencia de estos factores de virulencia en S. epidermidis, los cuáles hasta el momento se han reportado únicamente en S.aureus. Este hallazgo es importante ya que se sugiere la relación con transferencia horizontal de genes entre estas especies, siendo el S. epidermidis un importante reservorio genético, y un importante patobionte causal de infecciones nosocomiales, asociado con dispositivos médicos.


Abstract Adhesion factors are virulence determinants that are expressed in microorganisms with the ability to form biofilms, contributing to the severity of nosocomial infections. Among these microbial surface components recognizing adhesive matrix molecules (MSCRAMMs), are fibronectin binding A and B (fnbA and B) clumping A and B (ClfA and B) and fibrinogen binding (Fib) factors. All of these have been described in Staphylococcus aureus and react with human extracellular matrix proteins. The goal of this study was to determine adhesion factors related to the biofilm formation in Staphylococcus. Method. For these purpose, 30 clinical isolates of Staphylococcus aureus and Staphylococcus epidermidis, from immunocompromised patients in three hospitals in Bogotá were characterized both, genotypically and phenotypically. The biofilm formation was determined through Congo Red and Violet Crystal and the genes FnbA, B, ClfA, B, Fib and operon ica ADBC were amplified through conventional and multiplex PCR. Results. Every clinical isolate were genotypically and phenotypically positive for the biofilm formation, being found the presence of the whole ica ADBC operon in 88,9%. The ClfA and ClfB were found by 70%; Fib 60%, fnbB 23% and 17% offnbA. Conclusions. This study proved the presence of these virulence factors in S. epidermidis, which so far have only been reported in S. aureus. This finding is important because it suggestes the relationship with horizontal gene transfer between these species, being the S. epidermidis an important genetic reservoir and a causal patobiont of nosocomial infections associated with medical devices.


Assuntos
Humanos , Staphylococcus aureus , Staphylococcus epidermidis , Vírus , Aderência Bacteriana
13.
Braz. j. microbiol ; 48(2): 225-231, April.-June 2017. graf
Artigo em Inglês | LILACS | ID: biblio-839393

RESUMO

Abstract Streptococcus pneumoniae is one of the most frequent opportunistic pathogens worldwide. DNA processing protein A (DprA) is an important factor involved in bacterial uptake and DNA integration into bacterial genome, but its role in S. pneumoniae virulence remains unclear. The aim of this study was to characterize the effects of the pneumococcal dprA gene on the pathogenesis of S. pneumoniae. To construct a dprA-deficient pneumococcal strain, the dprA gene of the S. pneumoniae strain D39 was inactivated. The virulence of this dprA-deficient strain, designated ΔD39, was compared with that of the wild-type strain by evaluating their respective capabilities to adhere to human pulmonary epithelial cells (PEC-A549) and by analyzing their choline-binding protein expression levels. In addition, the expression profiles of genes associated with virulence and host survival assays were also conducted with the mutant and the wild-type strain. Our results indicate that the capability of ΔD39 to adhere to the PEC-A549 airway cells was significantly lower (p < 0.01) compared with D39. Additionally, the 100-KD choline-binding protein was not detected in ΔD39. The addition of competence-stimulating peptide (CSP) lead to a significantly reduction of psaA mRNA expression in the dprA-deficient mutant and an increased level of psaA transcripts in the wild-type strain (p < 0.01). The median survival time of mice intraperitoneally infected with ΔD39 was significantly higher (p < 0.01) than that of mice infected with D39. The results of this study suggest that DprA has a significant effect on virulence characteristics of S. pneumoniae by influencing the expression of choline-binding protein and PsaA.


Assuntos
Humanos , Animais , Infecções Pneumocócicas/patologia , Streptococcus pneumoniae/patogenicidade , Proteínas de Bactérias/metabolismo , Aderência Bacteriana , Fatores de Virulência/análise , Proteínas de Membrana/metabolismo , Infecções Pneumocócicas/microbiologia , Streptococcus pneumoniae/genética , Proteínas de Bactérias/análise , Proteínas de Bactérias/genética , Análise de Sobrevida , Linhagem Celular , Fatores de Virulência/genética , Modelos Animais de Doenças , Células Epiteliais/microbiologia , Técnicas de Inativação de Genes , Proteínas de Membrana/genética , Camundongos
14.
Braz. dent. j ; 28(1): 24-29, Jan.-Feb. 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-839123

RESUMO

Abstract The aim was to evaluate the surface roughness and bacterial adhesion on enamel irradiated with high intensity lasers, associated or not to a fluoride varnish. Eighty fragments of bovine enamel were equally divided in 8 groups (n=10). Group 1 was not treated and Group 2 received only a 5% fluoride varnish application. The other groups were irradiated with an Er:Cr:YSGG (8.92 J/cm2), an Nd:YAG (84.9 J/cm2) and a diode laser (199.04 J/cm2), associated or not to a 5% fluoride varnish. The surface roughness was measured before and after treatments. Afterward, all samples were incubated in a suspension of S. mutans at 37 °C for 24 h. The colony-forming units (CFU) were counted by a stereoscope and the results were expressed in CFU/mm2. One-way ANOVA and the Tukey´s test compared the roughness data and the Student´s test compared the results obtained in the bacterial adhesion test (a=5%). The results showed that the irradiated samples without varnish presented the same roughness and the same bacterial adhesion that the non-irradiated samples. However, samples irradiated in the presence of fluoride varnish showed higher surface roughness and higher bacterial adhesion than the non-irradiated samples and those irradiated without varnish. Presence of pigments in the varnish increased the lasers’ action on the enamel surface, which produced ablation in this hard tissue and significantly increased its surface roughness. For this reason, the enamel’s susceptibility to bacterial adhesion was higher when the irradiation of the samples was made in presence of fluoride varnish.


Resumo O objetivo foi avaliar a rugosidade superficial e adesão bacteriana no esmalte dental irradiado com lasers de alta intensidade, associados ou não a um verniz fluoretado. Oitenta fragmentos de esmalte foram igualmente divididos em 8 grupos (n= 10). O grupo 1 não recebeu tratamento e o grupo 2 recebeu aplicação de verniz fluoretado a 5%. Os outros grupos foram irradiados com os lasers Er,Cr:YSGG (8,92 J/cm2), Nd:YAG (84,9 J/cm2) e um laser de diodo (199,04 J/cm2), associados ou não ao verniz fluoretado. A rugosidade superficial foi medida antes e após os tratamentos. Depois, todas as amostras foram imersas em suspensão de S. mutans a 37 °C durante 24 h. As unidades formadoras de colônia (UFC) foram contadas utilizando uma lupa estereoscópica, e os resultados foram expressos em UFC/mm2. Os resultados de rugosidade foram analisados por ANOVA e pelo teste de Tukey, e a adesão bacteriana foi analisada pelo teste de Student (a=5%). As amostras irradiadas sem verniz apresentaram a mesma rugosidade superficial e a mesma adesão bacteriana que as amostras não irradiadas. No entanto, as amostras irradiadas na presença do verniz fluoretado apresentaram maior rugosidade superficial e aderência bacteriana do que as amostras não irradiadas e daquelas irradiadas sem o verniz. A presença de pigmentos no verniz aumentou a ação dos lasers na superfície do esmalte, promovendo a ablação do tecido duro e aumentando significativamente a sua rugosidade superficial. Por isso, a adesão bacteriana no esmalte foi maior quando a irradiação foi realizada na presença do verniz fluoretado.


Assuntos
Animais , Bovinos , Streptococcus mutans/efeitos da radiação , Aderência Bacteriana/efeitos da radiação , Lasers de Estado Sólido , Streptococcus mutans/isolamento & purificação , Streptococcus mutans/fisiologia , Propriedades de Superfície , Técnicas In Vitro , Contagem de Colônia Microbiana , Esmalte Dentário/efeitos da radiação
15.
Rev. ADM ; 74(1): 40-45, ene.-feb. 2017. tab, graf
Artigo em Espanhol | LILACS | ID: biblio-869351

RESUMO

Introducción: el material usado para fabricar aparatos protésicos parciales o totales es el polimetilmetacrilato, el cual forma una superficie sólida que se encuentra en íntimo contacto con la mucosa bucal del paciente, esta superfi cie puede presentar defectos (poros, grietas e irregularidades), que se producen al momento de su elaboracióny varían según la técnica de procesado, actuando como reservorios que contribuyen a la adherencia y proliferación de microorganismos,dentro de los cuales, el más frecuentemente aislado en pacientesportadores de prótesis es Candida albicans. Objetivo: Identifi car lasbacterias presentes en la superfi cie de una resina acrílica para base dedentadura (ProBase Hot®, Ivoclar, Vivadent). Material y métodos: Se seleccionaron 10 pacientes de ambos sexos, entre 25 y 30 años de edad que acudían a la clínica de prótesis. Las impresiones de alginato de los pacientes se utilizaron para crear modelos de yeso, que luegoconfeccionaron paladares de acrílico termocurado que los pacientes llevaban por un periodo de 24 horas. Una muestra del acrílico se tomóposteriormente para fi nes de identifi cación bacteriológica. El análisisestadístico consistió en estadística descriptiva con la distribución defrecuencia y porcentajes, realizando tablas de contingencia y respuestamúltiple (Programa IBM SPSS STATISTICS 21.0). Resultados: Labacteria identifi cada mayor número de veces fue Klebsiella pneumoniae,mientras que de las aisladas en menor frecuencia correspondió tanto a Escherichia coli como a Enterobacter cloacae, Pseudomonas aeruginosa en tres oportunidades, seguido de Enterococcus faecalis, Streptococcus alfa hemolítico y Streptococcus hyicus solo un par de veces. Conclusiones: La resina acrílica usada en este estudio diopositivo a diferentes especies bacterianas y las más frecuentementeaisladas pertenecen a la familia de las enterobacterias.


Introduction: the material most commonly used to make full orpartial prosthetic dental appliances is polymethyl methacrylate, whichprovides a solid surface that is in close contact with the patient’s oralmucosa. During the production of the dental prosthetic, defects suchas holes, cracks, and other irregularities can appear on this surface(depending on the method used), which act as reservoirs that stimulatethe proliferation of microorganisms and make it easier for these toadhere to the surface. The most frequently isolated microorganism indenture wearers is Candida albicans. Objective: To identify the bacteriapresent on the acrylic resin surface of dentures bases (ProBase Hot®,Ivoclar, Vivadent). Material and methods: 10 subjects of both sexesaged between 25 and 30 years were selected from among patientsattending a prosthodontics clinic. Alginate impressions of the patientswere used to create plaster molds, which were then used to constructheat-cured acrylic resin palatal plates that the patients wore for aperiod of 24 hours. A sample of the acrylic was subsequently takenfor bacteriological identifi cation purposes. Statistical analysis wasperformed based on a descriptive analysis of frequency distributionand percentages, and crossover and multiple response tables created(IBM SPSS STATISTICS 21.0 software). Results: The most frequentlyidentifi ed bacterium in this study was Klebsiella pneumoniae, whilethe least frequently isolated were Escherichia coli and Enterobactercloacae (once each), Pseudomonas aeruginosa (in three cases),and Enterococcus faecalis, Streptococcus alpha hemolytic andStreptococcus hyicus (two each). Conclusions: The acrylic resin usedin this study tested positive for various bacterial species, the mostfrequently isolated of these belonging to the family Enterobacteriaceae.


Assuntos
Humanos , Masculino , Adulto , Feminino , Adulto Jovem , Aderência Bacteriana , Estomatite sob Prótese/microbiologia , Resinas Acrílicas/efeitos adversos , Contagem de Colônia Microbiana , Meios de Cultura , Enterobacter/classificação , Enterobacter/crescimento & desenvolvimento , México , Análise Estatística
16.
Int. j. morphol ; 34(4): 1419-1423, Dec. 2016. ilus
Artigo em Inglês | LILACS | ID: biblio-840903

RESUMO

Campylobacter fetus is extracellular bacteria of the genital tract of cattle. They cause infertility and abortion, but there is no documented information on the susceptibility of bovine sperm cells to this bacteria. The aim of this present work was to study the effects provoked by Campylobacter fetus subsp. venerealis when in interaction with bovine sperm cells. The bovine spermatozoa were obtained frozen bovine semen pooled from uninfected bulls, and were exposed to living campylobacter over different periods of time. Light microscopy and scanning electron microscopy first revealed a tropism, then a close proximity followed by tight adhesion between these two different cells. A decrease in the spermatozoa motility was observed. Motile bacteria were observed during the next 3 h, this process began with a tight membrane­membrane adhesion. The adhesion between Campylobacter fetus to the sperm cell occurred either by the flagella or by sperm head. Results from this study demonstrated with light microscopy scanning electron microscopy allowed us to characterize some aspects of the interaction of Campylobacter fetus subsp. venerealis and bovine sperm while preserving the cellular and bacterial structure. This ex vivo model might be useful for studies on adhesion and cytopathogenicity of different field strains of Campylobacter fetus.


Campylobacter fetus subsp. venerealis es un patógeno extracelular del tracto genital de bovinos. En las hembras causa subfertilidad y aborto, mientras que los toros son portadores en el esmegma prepucial y se desconoce si provoca daño en los espermatozoides. El objetivo del presente trabajo fue estudiar los efectos de Campylobacter fetus subsp. venerealis sobre espermatozoides bovinos. Los espermatozoides obtenidos a partir de pajuelas de semen pertenecientes a toros no infectados, se coincubaron con una cepa de Campylobacter fetus subsp. venerealis por diferentes períodos de tiempo. Por microscopía óptica y electrónica de barrido se observó el tropismo inicial de la bacteria hacia los espermatozoides y la adhesión bacteriana, de forma colateral se observó su efecto en el espermograma. Post incubación los espermatozoides presentaron menor motilidad progresiva y mayor porcentaje de muertos con respecto al control. Se comprobó la viabilidad de la bacteria a las 3 h. Se registró la adhesión de Campylobacter fetus subsp. venerealis a la membrana celular de distintas porciones del espermatozoide: cabeza, pieza media, cuello y cola. Los resultados de este estudio permitieron caracterizar la interacción entre Campylobacter fetus subsp. venerealis y espermatozoides bovinos por microscopía óptica y electrónica de barrido. La aplicación de este modelo ex vivo permitirá profundizar los conocimientos referentes a los procesos de adhesión y citopatogenicidad de Campylobacter fetus.


Assuntos
Animais , Masculino , Bovinos , Campylobacter fetus/fisiologia , Espermatozoides/microbiologia , Aderência Bacteriana , Microscopia Eletrônica de Varredura , Espermatozoides/ultraestrutura
17.
Rev. otorrinolaringol. cir. cabeza cuello ; 76(3): 255-264, dic. 2016. ilus, graf
Artigo em Espanhol | LILACS | ID: biblio-845624

RESUMO

Introducción: La otitis externa infecciosa es una consulta otorrinolaringológica frecuente en usuarios de audífonos. Las propiedades antibacterianas descritas del cobre, han motivado el desarrollo de aplicaciones clínicas de este metal. Objetivo: Evaluar la capacidad antibacteriana de moldes de audífonos manufacturados con polímeros sensible a luz UV, silicona y acrílico que incorporan cobre metálico, en un sistema experimental in vitro. Material y método: Se diseñaron moldes de audífonos con y sin cobre, que fueron inoculados con distintas concentraciones de microorganismos (S aureus y P aeruginosa), para luego determinar el porcentaje de adherencia bacteriana a distintos tiempos de contacto (4, 8 y12 horas). Resultados: Existió reducción significativa en la adhesión bacteriana a los moldes con cobre respecto a aquellos sin cobre, independiente del material, del tipo de microorganismo y del inóculo bacteriano. Discusión: La disminución en la adherencia bacteriana en los prototipos con cobre, puede atribuirse a su actividad inhibitoria sobre los microorganismos en función de su concentración y el tiempo de contacto, ejerciendo su efecto por difusión a través de los distintos materiales. Conclusión: Con estos resultados, se hace necesario el desarrollo de estudios clínicos enfocados en comprobar si el uso de audífonos con cobre disminuyen las otitis externas de origen infeccioso.


Introduction: External otitis of infectious etiology among hearing aid users is a common motive of otolaryngology consultation. Antibacterial properties described copper, they have motivated the development of clinical applications of this metal. Aim: Evaluate the antibacterial capacity of copper-based ear molds manufactured with different materials such UV sensitive polymers, silicone and acrylic incorporating metallic copper, in an experimental system in vitro. Material and method: Ear molds with and without copper, were inoculated with different concentrations of microorganisms (S aureus and P aeruginosa) and determine the percentage of bacterial adherence to different contact times (4-8 and 12 hours). Results: There was significant reduction in bacterial adhesion to copper molds than those without copper, independent of the material, the type of microorganism and the bacterial inoculum. Discussion: The decrease in bacterial adherence on prototypes with copper, can be attributed to inhibitory activity on microorganisms depending on their concentration and contact time, exerting its effect by diffusion through the various materials. Conclusion: With these results, is necessary the development of clinical studies focused on checking whether the use of hearing aids with copper decreases external otitis of infectious origin.


Assuntos
Humanos , Antibacterianos/farmacologia , Cobre/química , Auxiliares de Audição/microbiologia , Pseudomonas aeruginosa/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Aderência Bacteriana/efeitos dos fármacos , Otite Externa/prevenção & controle
18.
ImplantNewsPerio ; 1(8): 1501-1507, nov.-dez. 2016. ilus, tab
Artigo em Português | LILACS, BBO - Odontologia | ID: biblio-848533

RESUMO

Objetivo: o presente estudo avaliou in situ a adesão bacteriana em função da rugosidade superficial das superfícies de titânio. Material e métodos: 24 discos de titânio (titânio grau 4; 4 mm de diâmetro x 3 mm de altura) foram divididos em quatro grupos: A) controle (liso/sem polimento); B) lixa 320; C) lixa 600; e D) lixa 1.200. Após tratamento, os discos foram fixados na região palatina de aparelhos ortodônticos, utilizados por três voluntários durante quatro horas para formação de biofilme. A adesão bacteriana foi avaliada quantitativamente por meio de imagens obtidas em microscopia eletrônica de varredura. Resultado: a rugosidade superficial foi alterada pelos tratamentos com as lixas, variando entre 0,084 µm e 0,324 µm (p < 0,05). A adesão bacteriana foi significativamente maior no grupo B (p=0,0082), apresentando uma área do titânio recoberta com biofilme de 67,68 pixels/µm2, enquanto o grupo A apresentou uma adesão 3,7 x menor. Conclusão: o aumento da rugosidade superficial aumentou significativamente a adesão bacteriana do biofilme dental in situ, após quatro horas. Futuros estudos são necessários para avaliar a maturação e futura colonização bacteriana por outras espécies que sucedem a colonização inicial.


Objective: the present study evaluated, in situ, the bacterial adhesion based on the titanium roughness surface. Material and methods: 24 titanium disks (titanium grade IV, 4 mm diameter and 3 mm high) were divided in 4 groups: A) control (smooth/without treatment); B) 320 grit sandpaper; C) 600 grit sandpaper, and D) 1.200 grit sandpaper. After treatment, all the disks were fixed at palatal area of orthodontic appliances on 3 volunteers during 4 hours after biofilm formation. The bacterial adhesion was quantitatively evaluated during the first hours using scanning electron microscopy images. Results: the superficial roughness was altered by the sandpaper treatment between 0.084 and 0.324 µm (p < 0.05). The bacterial adhesion was statistically higher for the group B (p=0.0082), depicting titanium area cover by biofilm of 67.68 pixels/µm2, while in group A the adhesion was a 3-fold lower. Conclusion: the superficial roughness increases significantly in situ bacterial adhesion four hours later. Further studies are need to evaluate the maturation and future succession bacterial colonization by other species in the succession after the early events.


Assuntos
Humanos , Masculino , Feminino , Adulto , Aderência Bacteriana , Implantes Dentários , Microscopia Eletrônica de Varredura , Estudos de Avaliação como Assunto , Titânio/análise
19.
Braz. dent. j ; 27(3): 255-260, May-June 2016. tab, graf
Artigo em Inglês | LILACS | ID: lil-782824

RESUMO

Abstract The periodontopathogen Aggregatibacter actinomycetemcomitans colonizes oral cavity by binding to and invading epithelial cells as well as by participating in biofilms formed on hard surfaces. Aae, an autotransporter protein, is implicated in bacterial adhesion to epithelial cells. Due to the multiple functions of bacterial autotransporter proteins, this study aimed to evaluate the role of aae in A. actinomycetemcomitans ability to adhere to both saliva-coated hydroxyapatite (SHA) and biofilm. An aae null mutant was constructed. Its hydrophobic properties as well as its ability to adhere to epithelial cells, SHA and to form biofilm were evaluated and compared with the parental strain, A. actinomycetemcomitans VT1169. The aae null mutant showed reduced hydrophobicity, as well as decreased binding to SHA and biofilm formation compared to the parental strain. These data suggest that aae mediates A. actinomycetemcomitans adhesion to epithelial cells and may be involved in biofilm formation and interaction with adsorbed salivary proteins.


Resumo O peridontopatógeno Aggregatibacter actinomycetemcomitans coloniza a cavidade oral aderindo e invadindo as células epiteliais e participando da formação de biofilme em superfícies duras. Aae, uma proteína autotransportadora está relacionada com a adesão bacteriana às células epiteliais. Devido às múltiplas funções desempenhadas por proteínas bacterianas autotransportadoras, este estudo teve como objetivo avaliar o papel de aae de A. actinomycetemcomitans tanto na capacidade de aderir à hidroxiapatita recoberta por saliva (SHA), quanto a de formar biofilme. Um mutante nulo aae foi construído. Suas propriedades hidrofóbicas, bem como a sia capacidade para aderir às células epiteliais, à SHA e para formar biofilme foram avaliadas e comparadas com a cepa -mãe, A. Actinomycetemcomitans VT1169. O mutante nulo aae apresentou redução de hidrofobicidade, assim como diminuição da adesão à SHA e na formação de biofilme, quando comparado à cepa parental. Estes dados sugerem que aae media a adesão de A. Actinomycetemcomitans às células epiteliais e pode também estar envolvida na formação de biofilme e na interação com proteínas salivares adsorvidas.


Assuntos
Aggregatibacter actinomycetemcomitans/fisiologia , Aderência Bacteriana/fisiologia , Proteínas de Bactérias/fisiologia , Proteínas de Membrana Transportadoras/fisiologia , Aggregatibacter actinomycetemcomitans/genética , Proteínas de Bactérias/genética , Biofilmes , Técnicas de Silenciamento de Genes , Interações Hidrofóbicas e Hidrofílicas , Proteínas de Membrana Transportadoras/genética
20.
Braz. j. microbiol ; 47(2): 414-416, Apr.-June 2016. graf
Artigo em Inglês | LILACS | ID: lil-780834

RESUMO

Abstract Escherichia coli is the major causative agent of human cystitis. In this study, a preliminary molecular analysis carried out by PCR (polymerase chain reaction) demonstrated that 100% of 31 E. coli strains isolated from patients with recurrent UTIs (urinary tract infections) showed the presence of the curli fimbria gene (csgA). Curli fimbria is known to be associated with bacterial biofilm formation but not with the adhesion of human cystitis-associated E. coli. Therefore, this work aimed to study how curli fimbria is associated with uropathogenic E. coli (UPEC) as an adhesion factor. For this purpose, the csgA gene was deleted from strain UPEC-4, which carries three adhesion factor genes (csgA, fimH and ompA). The wild-type UPEC-4 strain and its mutant (ΔcsgA) were analyzed for their adhesion ability over HTB-9 (human bladder carcinoma), Vero (kidney cells of African green monkey) and HUVEC (human umbilical vein) cells in the presence of α-D-mannose. All the wild-type UPEC strains tested (100%) were able to adhere to all three cell types, while the UPEC-4 ΔcsgA mutant lost its adherence to HTB-9 but continued to adhere to the HUVEC and Vero cells. The results suggest that curli fimbria has an important role in the adhesion processes associated with human UPEC-induced cystitis.


Assuntos
Humanos , Adesinas de Escherichia coli/metabolismo , Cistite/microbiologia , Proteínas de Escherichia coli/metabolismo , Infecções por Escherichia coli/microbiologia , Escherichia coli Uropatogênica/metabolismo , Aderência Bacteriana , Regulação Bacteriana da Expressão Gênica , Deleção de Sequência , Adesinas de Escherichia coli/genética , Proteínas de Escherichia coli/genética , Escherichia coli Uropatogênica/genética
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