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Adhesion and biofilm formation by Staphylococcus aureus from food processing plants as affected by growth medium, surface type and incubation temperature

Jerônimo,Heloísa Maria Ângelo; Queiroga,Rita de Cássia Ramos do Egypto; Costa,Ana Caroliny Vieira da; Barbosa,Isabella de Medeiros; Conceição,Maria Lúcia da; Souza,Evandro Leite de
Fonte: Universidade de São Paulo, Faculdade de Ciências Farmacêuticas Publicador: Universidade de São Paulo, Faculdade de Ciências Farmacêuticas
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2012 EN
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This study assessed the effect of different growth media [BHI broth, BHI broth plus glucose (10 g/100 mL) and BHI broth plus NaCl (5 g/100 mL)] and incubation temperatures (28 or 37 ºC) on the adherence, detachment and biofilm formation on polypropylene and stainless steel surfaces (2 x 2 cm coupons) for a prolonged period (24-72 h) by some strains of Staphylococcus aureus (S3, S28 and S54) from food processing plants. The efficacy of the sanitizers sodium hypochlorite (250 mg/mL) and peracetic acid (30 mg/mL) in reducing the number of viable bacterial cells in a preformed biofilm was also evaluated. S. aureus strains adhered in highest numbers in BHI broth, regardless of the type of surface or incubation temperature. Cell detachment from surfaces revealed high persistence over the incubation period. The number of cells needed for biofilm formation was noted in all experimental systems after 3 days. Peracetic acid and sodium hypochlorite were not efficient in completely removing the cells of S. aureus adhered onto polypropylene and stainless steel surfaces. From these results, the assayed strains revealed high capacities to adhere and form biofilms on polypropylene and stainless steel surfaces under the different growth conditions...

Nursery of the pink shrimp Farfantepenaeus paulensis in cages with artificial substrates: Biofilm composition and shrimp performance

Ballester, Eduardo Luis Cupertino; Wasielesky Junior, Wilson; Cavalli, Ronaldo Oliveira; Abreu, Paulo Cesar Oliveira Vergne de
Fonte: Universidade Federal do Rio Grande Publicador: Universidade Federal do Rio Grande
Tipo: Artigo de Revista Científica
ENG
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The use of artificial substrate (polyethylene screens) was investigated during the nursery rearing of the pink shrimp Farfantepenaeus paulensis cultured in fixed cages installed in a shallow estuarine inlet of the Patos Lagoon, southern Brazil. High water renewal rates during the experimental period kept water quality in the suitable range for penaeid shrimp culture. Although shrimp were fed a high quality artificial diet (40% protein) throughout the experiment, they were observed to occupy the substrates and actively graze on the biofilm. The bulk of the biofilm was composed of diatoms, filamentous cyanobacteria, protozoa and nematodes. Biofilm chlorophyll a concentration was significantly affected by shrimp grazing pressure and the composition of the diatom community suffered significant changes after shrimp introduction to the cages. At the end of the trial shrimp reared in the presence of artificial substrates achieved significant higher survival, growth and total biomass (pb0.05). Biofilm was likely an additional source of food for the reared animals.

Importance of biofilm for water quality and nourishment in intensive shrimp culture

Thompson, Fabiano Lopes; Abreu, Paulo Cesar Oliveira Vergne de; Wasielesky, Wilson
Fonte: Universidade Federal do Rio Grande Publicador: Universidade Federal do Rio Grande
Tipo: Artigo de Revista Científica
ENG
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Experiments were conducted to test the usefulness of biofilms???a microbial consortium associated with extracellular polymeric substances attached to submersed surfaces???in reducing the levels of ammonium and phosphate of rearing system water, and as a food source for the shrimp Farfantepenaeus paulensis. A mature biofilm, which is able to keep ammonium and phosphate at low levels, occurred 10???15 days after tank cleanup, and was characterized by chlorophyll-a concentration around 5 mgrcm2. It was mainly composed of pennate diatoms ?? Amphora, Campylopyxis, Na??icula, Sinedra, Hantschia and Cylindrotheca; ca. 9=104 cellsrmg of biofilm.and filamentous cyanobacteria??Oscillatoria and Spirulina; ca. 2=105 cellsrmg., though bacteria ??max. 1.48=107rmg., flagellates??max. 1.08=103rmg.and ciliates??max.3.51=102rmg. were also present. Pennate diatoms and filamentous cyanobacteria were responsible for the largest uptake of ammonium from the water, but nitrifying bacteria also played an important role. The presence of a biofilm lead to reduced exportation of phosphorus ??33% less phosphate. and to a higher output of nitrateqnitrite, instead of ammonium. Biofilm was also an important complementary food source for the shrimp, increasing their growth. q2002 Elsevier Science B.V. All rights reserved.

Inhibitory effects of 7-epiclusianone on glucan synthesis, acidogenicity and biofilm formation by Streptococcus mutans

Murata, Ramiro Mendon?a; Almeida, Luciana Salles Branco de; Yatsuda, Regiane; Santos, Marcelo Henrique dos; Nagem, Tanus Jorge; Rosalen, Pedro Luiz; Koo, Hyuin
Fonte: Universidade Federal de Ouro Preto Publicador: Universidade Federal de Ouro Preto
Tipo: Artigo publicado em periodico
EN_US
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Inhibitory effects of 7-epiclusianone on glucan synthesis, acidogenicity and biofilm formation by Streptococcus mutans The aim of this study was to examine the effects of 7-epiclusianone, a new prenylated benzophenone isolated from the plant Rheedia gardneriana, on some of the virulence properties of Streptococcus mutans associated with biofilm develop-ment and acidogenicity. The synthesis of glucans by glucosyltransferases B (GTF B) and C (GTF C) was markedly reduced by 7-epiclusianone showing more than 80% inhibition of enzymatic activity at a concentration of 100 mgmL1 . Double-reciprocal analysis (Lineweaver?Burk plots) revealed that the inhibition of GTF B activity was noncompetitive (mixed) while GTF C was inhibited uncompetitively. The glycolytic pH drop by S. mutans cells was also disrupted by 7-epiclusianone without affecting the bacterial viability, an effect that can be attributed, in part, to inhibition of F-ATPase activity (61.1 3.0% inhibition at 100mgmL 1 ). Further-more, topical applications (1-min exposure, twice daily) of 7-epiclusianone (at 250 mgmL 1 ) disrupted biofilm formation and physiology. The biomass (dry-weight), extracellular insoluble polysaccharide concentration and acidogenicity of the biofilms were significantly reduced by the test agent ( P o 0.05). The data show that 7-epiclusianone disrupts the extracellular and intracellular sugar metabolism of S. mutans...

The inability of Streptococcus mutans and Lactobacillus acidophilus to form a biofilm in vitro on dentine pretreated with ozone

Knight, G.; McIntyre, J.; Craig, G.; Mulyani, I.; Zilm, P.
Fonte: Australian Dental Assn Inc Publicador: Australian Dental Assn Inc
Tipo: Artigo de Revista Científica
Publicado em //2008 EN
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BACKGROUND: The use of ozone therapy in the treatment of dental caries is equivocal. The aim of this study was to use an in vitro model to determine the effects of prior ozone application to dentine on biofilm formation and to measure any associated reduction in bacteria viability. METHODS: Twenty dentine discs were bonded to the bases of 5 mL polycarbonate screw top vials. Ten dentine discs were infused with ozone for 40 seconds, 10 samples remained untreated as a control. The vials were filled with nutrient medium, sterilized and placed into the outflow from a continuous chemostat culture of Streptococcus mutans and Lactobacillus acidophilus for four weeks. At the conclusion of the experiment bacterial growth was monitored by taking optical density readings of the growth medium in each vial and the outer surface of the dentine specimens were examined by scanning electron microscopy as shown by SEM analysis. RESULTS: Ozone infusion prevented biofilm formation on all the treated samples while there was substantial biofilm present on the control specimens. While the average optical density of the control specimens was almost twice that of the ozone infused dentine (0.710 for the control with a SD of 0.288 and 0.446 for the ozonated samples with a SD of 0.371)...

Noninvasive Staphylococcus aureus biofilm determination in chronic rhinosinusitis by detecting the exopolysaccharide matrix component poly-N-acetylglucosamine

Foreman, A.; Jervis-Bardy, J.; Boase, S.; Tan, L.W.; Wormald, P.J.
Fonte: American Rhinologic Society Publicador: American Rhinologic Society
Tipo: Artigo de Revista Científica
Publicado em //2013 EN
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BACKGROUND The role that bacterial biofilms might play in recalcitrant forms of chronic rhinosinusitis (CRS) is increasingly being recognized. However, the detection of bacteria existing in this form, using standard culture, is limited by their unique metabolically inactive properties. All current biofilm diagnostic modalities require invasive mucosal biopsies, which limit their use to the operating theatre. METHODS Twenty CRS patients and 5 controls were enrolled in a prospective study to assess the feasibility of noninvasively diagnosing S. aureus biofilms by detecting the biofilm matrix polysaccharide poly-N-acetylglucosamine (PNAG). An immunofluorescence protocol was developed for PNAG detection and compared with both standard microbiological cultures and fluorescence in situ hybridization (FISH). RESULTS Thirteen of 20 CRS patients had evidence of S. aureus biofilm formation using FISH. Of these, 12 had detectable PNAG. Interestingly none of the S. aureus FISH-negative patients were PNAG-positive despite the presence of coagulase-negative Staphylococci biofilms, some of which may exhibit PNAG in their pathogenic forms. The development of a noninvasive S. aureus biofilm diagnostic test provides a reliable means to identify a high-risk group of CRS patients who harbor S. aureus biofilms. The ability to be used outside of the perioperative period to assess surgical efficacy...

Wild mushroom extracts as inhibitors of bacterial biofilm formation

Alves, Maria José; Ferreira, Isabel C.F.R.; Lourenço, Inês; Costa, Eduardo; Martins, Anabela; Pintado, Manuela
Fonte: Instituto Politécnico de Bragança Publicador: Instituto Politécnico de Bragança
Tipo: Conferência ou Objeto de Conferência
ENG
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Introduction: Microorganisms can colonize a wide variety of medical devices, putting patients in risk for local and systemic infectious complications. These microorganisms are able to grow adhered to almost every surface, forming biofilms. The use of natural products has been successful in the discovery of new medicine, and mushrooms could be a source of natural antimicrobials. Objectives: The present study reports the capacity of wild mushroom extracts to inhibit in vitro biofilm formation by multi-resistant bacteria. Methods: Four Gram-negative bacteria biofilm producers (Escherichia coli, Proteus mirabilis, Pseudomonas aeruginosa and Acinetobacter baumannii) isolated from urine were used to verify the activity of Russula delica, Fistulina hepatica, Mycena rosea, Leucopaxilus giganteus and Lepista nuda extracts. Results: The results obtained showed that all tested mushroom extracts presented some extent of inhibition of biofilm production. Pseudomonas aeruginosa was the microorganism with the highest capacity of biofilm production, being also the most susceptible to the extracts inhibition capacity (≥ 50%). Among the five tested extracts against E. coli, Leucopaxillus giganteus (47.8%) and Mycenas rosea (44.8%) presented the highest inhibition of bio

Lactobacillus acidophilus ATCC 4356 inhibits biofilm formation by C. albicans and attenuates the experimental candidiasis in Galleria mellonella

Vilela, Simone F. G.; Barbosa, Junia O.; Rossoni, Rodnei D.; Santos, Jessica D.; Prata, Marcia C. A.; Anbinder, Ana Lia; Jorge, Antonio O. C.; Junqueira, Juliana C.
Fonte: Taylor &francis Inc Publicador: Taylor &francis Inc
Tipo: Artigo de Revista Científica Formato: 29-39
ENG
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Processo FAPESP: 2012/02184-9; Processo FAPESP: 2012/19915-6; Processo FAPESP: process 2011/15194-0; Probiotic strains of Lactobacillus have been studied for their inhibitory effects on Candida albicans. However, few studies have investigated the effect of these strains on biofilm formation, filamentation and C. albicans infection. The objective of this study was to evaluate the influence of Lactobacillus acidophilus ATCC 4356 on C. albicans ATCC 18804 using in vitro and in vivo models. In vitro analysis evaluated the effects of L. acidophilus on the biofilm formation and on the capacity of C. albicans filamentation. For in vivo study, Galleria mellonella was used as an infection model to evaluate the effects of L. acidophilus on candidiasis by survival analysis, quantification of C. albicans CFU/mL, and histological analysis. The direct effects of L. acidophilus cells on C. albicans, as well as the indirect effects using only a Lactobacillus culture filtrate, were evaluated in both tests. The in vitro results showed that both L. acidophilus cells and filtrate were able to inhibit C. albicans biofilm formation and filamentation. In the in vivo study, injection of L. acidophilus into G. mellonella larvae infected with C. albicans increased the survival of these animals. Furthermore...

Antibacterial, anti-swarming and anti-biofilm formation activities of Chamaemelum nobile against Pseudomonas aeruginosa

Kazemian,Hossein; Ghafourian,Sobhan; Heidari,Hamid; Amiri,Pouya; Yamchi,Jalil Kardan; Shavalipour,Aref; Houri,Hamidreza; Maleki,Abbas; Sadeghifard,Nourkhoda
Fonte: Sociedade Brasileira de Medicina Tropical - SBMT Publicador: Sociedade Brasileira de Medicina Tropical - SBMT
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/08/2015 EN
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AbstractINTRODUCTION:Chamomile ( Chamaemelum nobile ) is widely used throughout the world, and has anti-inflammatory, deodorant, bacteriostatic, antimicrobial, carminative, sedative, antiseptic, anti-catarrhal, and spasmolytic properties. Because of the increasing incidence of drug-resistant bacteria, the development of natural antibacterial sources such as medical herbs for the treatment of infectious diseases is necessary. Extracts from different plant parts such as the leaves, flowers, fruit, and bark of Combretum albiflorum, Laurus nobilis , and Sonchus oleraceus were found to possess anti-quorum sensing (QS) activities. In this study, we evaluated the effect of C. nobile against Pseudomonas aeruginosa biofilm formationMETHODS:The P. aeruginosa samples were isolated from patients with different types of infection, including wound infection, septicemia, and urinary tract infection. The flowers of C. nobile were dried and the extract was removed using a rotary device and then dissolved in dimethyl sulfoxide at pH 7.4. The microdilution method was used to evaluate the minimum inhibitory concentration (MIC) of this extract on P. aeruginosa , and biofilm inhibition was assayed.RESULTS:Eighty percent of the isolated samples (16/20) could form a biofilm...

Influence of microleakage surface roughness and biofilm control on secondary caries formation around composite resin restorations an in situ evaluation

Lima, Fábio Garcia; Romano, Ana Regina; Correa, Marcos Britto; Demarco, Flávio Fernando
Fonte: University of São Paulo Publicador: University of São Paulo
Tipo: Artigo de Revista Científica
EN_US
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This study carried oud to evaluate in situ the influence of microlrakage, surface roughnen and biofilm control on caries formation aroud composite resin restorations. During 28 days, 12 voluters wore palatal devices containing bovine enamel slabs restored withe composite resin.Restorations werw made without leakege,when the adhesive system was applied, or with leakage, when adhesive system was omitted. Half of the remaining whe finished and polished. In one sid of the palatal device, biofilm was left to accumulate ove the slabs, and in the other side dental slabs whe brushed, to allow biofilm removal. There was an extraoral application of 20% sucrose solution (8x/ day) over the enamel slabs the formation of caries lesions ( withe spots)was evaluated by visual inspection under stereomicroscopy. Additionally, the dental slabs were sectioned and observed under polarized light microscopy.Data were submitted to kruskal-wallis test and spearman's correlation test at 5% significance level. Polishing and londing wew not significanct factors regorging with spot formation close to the restoration (p<0.01).Polarized light microcopy confirmed the visual inspection findings.These results suggest reat while microleakege and surface roughness did not influence caries lesion formation...

The global anaerobic regulator Anr, is involved in cell attachment and aggregation influencing the first stages of biofilm development in Pseudomonas extremaustralis

Tribelli, Paula Maria; Hay, Anthony; Lopez, Nancy Irene
Fonte: Public Library Science Publicador: Public Library Science
Tipo: info:eu-repo/semantics/article; info:ar-repo/semantics/artículo; info:eu-repo/semantics/publishedVersion Formato: application/pdf
ENG
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Pseudomonas extremaustralis is a versatile Antarctic bacterium, able to grow under microaerobic and anaerobic conditions and is related to several non-pathogenic Pseudomonads. Here we report on the role of the global anaerobic regulator Anr, in the early steps of P. extremaustralis biofilm development. We found that the anr mutant was reduced in its ability to attach, to form aggregates and to display twitching motility but presented higher swimming motility than the wild type. In addition, microscopy revealed that the wild type biofilm contained more biomass and was thicker, but were less rough than that of the anr mutant. In silico analysis of the P. extremaustralis genome for Anr-like binding sites led to the identification of two biofilm-related genes as potential targets of this regulator. When measured using Quantitative Real Time PCR, we found that the anr mutant expressed lower levels of pilG , which encodes a component of Type IV pili and has been previously implicated in cellular adhesion. Levels of morA, involved in signal transduction and flagella development, were also lower in the mutant. Our data suggest that under low oxygen conditions, such as those encountered in biofilms, Anr differentially regulates aggregation and motility thus affecting the first stages of biofilm formation.; Fil: Tribelli...

Regulación de factores de virulencia y biofilm en Xanthomonas spp; Regulation of virulence factors and biofilm in Xanthomonas spp.

Torres, Pablo Sebastián
Fonte: Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires Publicador: Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires
Tipo: info:eu-repo/semantics/doctoralThesis; tesis doctoral; info:eu-repo/semantics/publishedVersion Formato: application/pdf
Publicado em //2009 SPA
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Xanthomonas campestris pv. campestris (Xcc) y Xanthomonas axonopodis pv. citri (Xac) son los agentes causales de la pudrición negra en crucíferas y de la cancrosis de los cítricos, respectivamente. En ambas bacterias la producción de diversos factores de virulencia está regulada por un grupo de genes denominados rpf (por regulation of pathogenicity factors) a través de la síntesis y percepción de moléculas difusibles que ellas mismas producen y que se denominan DSF (diffusible signal factor). RpfF y RpfB son responsables de la biosíntesis de DSF y RpfC y RpfG están involucrados en su detección y posterior transducción de la señal al interior de la bacteria. Mutaciones en los genes rpfF y rpfC producen una reducción en la producción de enzimas y polisacáridos extracelulares, formación de biofilm y patogenicidad cuando son comparadas con las respectivas cepas silvestres, lo que involucra a estos genes en la regulación de factores involucrados en todos éstos procesos. Entre éstos, hemos detectado un nuevo factor que es secretado por Xcc, que tiene la propiedad de revertir el cierre de estomas inducido por ácido Absísico (ABA), Lipopolisacárido (LPS) o bacterias. Las mutantes rprF y rpfC no pueden revertir el cierre de estomas...

Bacteriophage reduces biofilm of Staphylococcus aureus ex vivo isolates from chronic rhinosinusitis patients

Drilling, A.; Morales, S.; Jardeleza, C.; Vreugde, S.; Speck, P.; Wormald, P.J.
Fonte: OceanSide Publications Publicador: OceanSide Publications
Tipo: Artigo de Revista Científica
Publicado em //2014 EN
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Background: Staphylococcus aureus is the most common organism in recalcitrant chronic rhinosinusitis (CRS) and is often resistant to traditional antibiotic therapy. Bacteriophages (“phages”) are a potential candidate for a new, effective therapy. For phages to be useful in the setting of CRS, two minimum requirements must be presented: (1) phages must be effective against S. aureus biofilms and (2) phages must have a broad spectrum of activity. This study aimed to assess the in vitro activity of a phage cocktail (CockTail of Staphylococcus aureus specific bacteriophage [CT-SA]) against S. aureus biofilms and a broad panel of strains isolated from patients with CRS. Methods: The study examined 66 clinical isolates (CIs) of S. aureus. All isolates were tested for the susceptibility to phage lysis by spotting CT-SA onto bacterial lawns. To measure its effect on S. aureus biofilms, a minimum biofilm eradication concentration assay was used, using five S. aureus isolates. Biofilms of these isolates were grown, treated with CT-SA for 48 hours, fluorescently stained, and viewed using confocal scanning laser microscopy. Results: CT-SA lysed 62 of 66 (94%) CIs of S. aureus. CT-SA treatment yielded significant reductions in biofilm mass for 4/5 CIs tested and for ATCC 25923. Challenge of S. aureus with a single phage resulted in the emergence of bacteriophage-insensitive mutants (BIM) with a frequency of 10−7...

Biofilmes monoespécie e multiespécies de patógenos gram-positivos de origem láctea em diferentes substratos; Mono-specie and multi-species biofilm of gram-positives pathogens isolated from dairy products in different substrates

Vanessa Pereira Perez Alonso
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 04/09/2015 PT
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Patógenos causadores de Doenças transmitidas por alimentos (DTAs), frequentemente são encontrados em produtos lácteos e preocupam a indústria de alimentos por sua capacidade de formação de biofilme em superfícies de aço inoxidável. Bacillus cereus, Enterococcus faecalis, Listeria monocytogenes e Staphylococcus aureus são patógenos Gram positivos encontrados em produtos lácteos e, neste estudo, a capacidade de formação de biofilme monoespécie e multiespécies em superfície de aço inoxidável a 25ºC em diferentes substratos foram avaliadas. A formação de biofilmes foi verificada pela técnica da contagem em placas nos tempos 6h, 24h, 48h, 96h, 168h e 220h. Os cupons de aço inoxidável (AISI 304) foram colocados em diferentes substratos, caldo infusão de cerebro e coração (BHI), soro de leite e leite desnatado, inoculados com aproximadamente 103 UFC/ml de patógenos de origem láctea. Os micro-organismos avaliados foram capazes de formar biofilmes monoespécie e multiespécies, com contagens de até 7 log UFC/cm2. Foi observado maior esporulação do B. cereus em caldo BHI e leite desnatado, quando comparado com soro de leite. E. faecalis apresentou maior crescimento quando em biofilme multiespécies e quando em monoespécie maior equilíbrio entre os diferentes substratos. Por outro lado...

Antibacterial efficacy of intracanal medicaments on bacterial biofilm: a critical review

Estrela, Carlos; Sydney, Gilson Blitzkow; Figueiredo, José Antonio Poli; Estrela, Cyntia Rodrigues de Araújo
Fonte: Universidade de São Paulo. Faculdade de Odontologia de Bauru Publicador: Universidade de São Paulo. Faculdade de Odontologia de Bauru
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; ; ; Formato: application/pdf
Publicado em 01/02/2009 ENG
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The purpose of this paper is to discuss critically the antibacterial efficacy of intracanal medicaments on bacterial biofilm. Longitudinal studies were evaluated by a systematic review of English-language articles retrieved from electronic biomedical journal databases (MEDLINE, EMBASE, CENTRAL) and handsearching records, using different matches of keywords for root canal biofilm, between 1966 and August 1st, 2007. The selected articles were identified from titles, abstracts and full-text articles by two independent reviewers, considering the tabulated inclusion and exclusion criteria. Disagreements were resolved by consensus. The search retrieved 91 related articles, of which 8.8% referred to in vivo studies demonstrating the lack of efficacy of endodontic therapy on bacterial biofilm. Intracanal medicaments were found to have a limited action against bacterial biofilm.

Influence of microleakage, surface roughness and biofilm control on secondary caries formation around composite resin restorations: an in situ evaluation

Lima, Fábio Garcia; Romano, Ana Regina; Correa, Marcos Britto; Demarco, Flávio Fernando
Fonte: Universidade de São Paulo. Faculdade de Odontologia de Bauru Publicador: Universidade de São Paulo. Faculdade de Odontologia de Bauru
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; ; Formato: application/pdf
Publicado em 01/02/2009 ENG
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This study was carried out to evaluate in situ the influence of microleakage, surface roughness and biofilm control on caries formation around composite resin restorations. During 28 days, 12 volunteers wore palatal devices containing bovine enamel slabs restored with composite resin. Restorations were made without leakage, when the adhesive system was applied, or with leakage, when adhesive system was omitted. Half of the restorations in each group were finished and the remaining were finished and polished. In one side of the palatal device, biofilm was left to accumulate over the restored slabs, and in the other side dental slabs were brushed, to allow biofilm removal. There was an extraoral application of 20% sucrose solution (8x/day) over the enamel slabs. The formation of caries lesions (white spots) was evaluated by visual inspection under stereomicroscopy. Additionally, the dental slabs were sectioned and observed under polarized light microscopy. Data were submitted to Kruskal-Wallis test and Spearman's correlation test at 5% significance level. Polishing and bonding were not significant factors regarding white spot formation (p>;0.05). Biofilm control (brushing) was associated with reduction of caries formation close to the restorations (p

Adhesion and biofilm formation by Staphylococcus aureus from food processing plants as affected by growth medium, surface type and incubation temperature

Jerônimo, Heloísa Maria Ângelo; Queiroga, Rita de Cássia Ramos do Egypto; Costa, Ana Caroliny Vieira da; Barbosa, Isabella de Medeiros; Conceição, Maria Lúcia da; Souza, Evandro Leite de
Fonte: Universidade de São Paulo. Faculdade de Ciências Farmacêuticas Publicador: Universidade de São Paulo. Faculdade de Ciências Farmacêuticas
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; ; ; Formato: application/pdf
Publicado em 01/12/2012 ENG
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Este estudo teve como objetivo avaliar o efeito de diferentes meios de crescimento [caldo BHI, caldo BHI adicionado de glucose (10 g/100 mL) e caldo BHI adicionado de NaCl (5 g/100 mL)] e temperaturas de incubação (28 e 37 ºC) sobre a adesão, separação e formação de biofilme sobre superfícies (2 x 2 cm) de polipropileno e aço inoxidável durante longo tempo de incubação (24-72 h) por parte de cepas de Staphylococcus aureus (S3, S58 e S54) isoladas de plantas de processamento de alimentos. Também foi avaliada a eficácia dos sanitizantes hipoclorito de sódio (250 mg/mL) e ácido peracético (30 mg/mL) na redução do número de células bacterianas viáveis presentes em um biofilme pré-formado. As cepas de S. aureus aderiram em número mais elevado quando incubadas em caldo BHI em ambos os tipos de superfícies e temperaturas de incubação testadas. A separação das células das superfícies revelou alta persistência ao longo do período de incubação. Número de células necessário para a formação do biofilme foi detectado depois de três dias de incubação em todos os sistemas experimentais. O ácido peracético e o hipoclorito de sódio não foram eficientes em remover completamente a células de S. aureus aderidas sobre as superfícies de polipropileno e aço inoxidável. Os resultados obtidos revelaram alta capacidade das cepas ensaiadas em aderir e formar biofilme sobre superfícies de polipropileno e aço inoxidável sobre diferentes condições de crescimento e que as células na matriz do biofilme apresentaram-se resistentes à total remoção quando expostas aos sanitizantes hipoclorito de sódio e ácido peracético.; This study assessed the effect of different growth media [BHI broth...

The effect of sodium hypochlorite on Enterococcus faecalis when grown on dentine as a single- and multi-species biofilm

Yap, B.; Zilm, P.S.; Briggs, N.; Rogers, A.H.; Cathro, P.C.
Fonte: Wiley Publicador: Wiley
Tipo: Artigo de Revista Científica
Publicado em //2014 EN
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Enterococcus faecalis is often involved in the aetiology of apical periodontitis after endodontic treatment. This project aimed to establish, on dentine in vitro, a multi-species biofilm containing E. faecalis, and to determine if the organism had an increased resistance to sodium hypochlorite compared with an axenic biofilm. Biofilms were established on dentine discs in flow cells with either E. faecalis alone (axenic) or together with Fusobacterium nucleatum and Streptococcus sanguinis. Following treatment with either 0.9% sodium hypochlorite or saline, the viability of E. faecalis was determined by serial plating and qualitative analysis was performed by scanning electron microscopy and confocal laser scanning microscopy. Viable counts indicated that 0.9% NaOCl is highly effective against E. faecalis grown alone and as part of a multi-species biofilm (P = 0.0005 and P = 0.001, respectively). No significant difference in its survival in the two biofilm types was found (P = 0.8276).; Benlee Yap, Peter S. Zilm, Nancy Briggs, Anthony H. Rogers and Peter C. Cathro

Non-invasive methods for monitoring biofilm growth in industrial water systems

Gómez de Saravia,S. G.; Fernández Lorenzo de Mele,M.
Fonte: Latin American applied research Publicador: Latin American applied research
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/07/2003 EN
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Microbiological control in industrial environments is frequently restricted to monitor the number of planktonic (suspended) cells. However, this number is not often related with the microorganisms attached to the surfaces (sessile bacteria). The aim of this research work was to develop a method for monitoring biofilm growth and the biocidal efficacy through simple non-invasive ways. With this purpose, biofilms were formed on stainless steel coupons and after preset periods were removed and immersed in sterile solutions with and without biocide. The number of sessile cells attached on the metal surface and of planktonic cells that were shed from the biofilmed coupons (pcb) and grow in the initially sterile solutions were determined. Sessile cells were scrapped from the metal surface to be enumerated. The relation between the degree of growth of pcb and the reactivation capacity of the biofilm was evaluated. It could be observed that pcb growing in a nutrient non aggressive medium was related to the number of sessile cells that remain alive after the biocidal treatment. The early stages of the biofilm growth, the thickness of the biofilms and their microstructural characteristics before and after the biocidal treatment could be followed through optical microscopy using a non-invasive technique recently developed in the laboratory. Microscopic observations showed that the biofilm thickness varied to obliterate the unevenness of rough surfaces.

La placa dental como biofilm: ¿Cómo eliminarla?

Serrano-Granger,Jorge; Herrera,David
Fonte: RCOE Publicador: RCOE
Tipo: info:eu-repo/semantics/article; journal article; info:eu-repo/semantics/publishedVersion Formato: text/html; application/pdf
Publicado em 01/08/2005 SPA
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La forma natural de crecimiento de las bacterias en la cavidad oral es el biofilm. Los biofilm son los responsables de la caries y de las enfermedades periodontales, y presentan gran resistencia frente a los antimicrobianos. Por lo tanto, es necesario realizar estudios que analicen la eficacia de los colutorios en las acciones de penetrar el biofilm y producir una acción bactericida suficiente, o de evitar el desarrollo de los mismos. Actualmente, en este campo sólo se dispone de estudios (acordes con las normas ADA) que atestiguan la eficacia de los colutorios de clorhexidina y de los colutorios de aceites esenciales. Para que los antimicrobianos optimicen su efectividad debe realizarse una desestructuración previa del biofilm por medios físicos (cepillado, uso de hilo dental, profilaxis, raspado y alisado radicular, etc.).