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Sample records for subgingival biofilm samples

  1. Sampling Modification Effects in the Subgingival Microbiome Profile of Healthy Children

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    Santigli, Elisabeth; Trajanoski, Slave; Eberhard, Katharina; Klug, Barbara

    2017-01-01

    Background: Oral microbiota are considered major players in the development of periodontal diseases. Thorough knowledge of intact subgingival microbiomes is required to elucidate microbial shifts from health to disease. Aims: This comparative study investigated the subgingival microbiome of healthy children, possible inter- and intra-individual effects of modified sampling, and basic comparability of subgingival microprints. Methods: In five 10-year-old children, biofilm was collected from th...

  2. Changes in the subgingival biofilm composition after coronally positioned flap

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    Jadson Almeida Lima

    2011-02-01

    Full Text Available OBJECTIVES: This study evaluated the effects of coronally positioned flap (CPF on the subgingival biofilm composition. MATERIAL AND METHODS: Twenty-two subjects with gingival recessions were treated with CPF. Clinical parameters were assessed before and at 6 months after surgery. Subgingival biofilms were analyzed by checkerboard DNA-DNA hybridization technique for 40 bacterial species. RESULTS: Recession height, clinical attachment level and bleeding on probing improved significantly (p<0.05 at 6 months post-CPF. The proportions of 10 periodontal pathogens and the proportions of red and orange complexes decreased at 6 months. CONCLUSION: In conclusion, CPF can induce beneficial effects on the composition of the subgingival microbiota after 6 months.

  3. Impact of early colonizers on in vitro subgingival biofilm formation.

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    Thomas W Ammann

    Full Text Available The aim of this study was to investigate the impact of early colonizing species on the structure and the composition of the bacterial community developing in a subgingival 10-species biofilm model system. The model included Streptococcus oralis, Streptococcus anginosus, Actinomycesoris, Fusobacterium nucleatum subsp. nucleatum, Veillonella dispar, Campylobacter rectus, Prevotella intermedia, Porphyromonas gingivalis, Tannerella forsythia, and Treponema denticola. Based on literature, we considered Streptococcus oralis, Streptococcus anginosus, and Actinomyces oris as early colonizers and examined their role in the biofilms by either a delayed addition to the consortium, or by not inoculating at all the biofilms with these species. We quantitatively evaluated the resulting biofilms by real-time quantitative PCR and further compared the structures using confocal laser scanning microscopy following fluorescence in situ hybridisation. The absence of the early colonizers did not hinder biofilm formation. The biofilms reached the same total counts and developed to normal thickness. However, quantitative shifts in the abundances of individual species were observed. In the absence of streptococci, the overall biofilm structure appeared looser and more dispersed. Moreover, besides a significant increase of P. intermedia and a decrease of P. gingivalis , P. intermedia appeared to form filamented long chains that resembled streptococci. A. oris, although growing to significantly higher abundance in absence of streptococci, did not have a visible impact on the biofilms. Hence, in the absence of the early colonizers, there is a pronounced effect on P. intermedia and P. gingivalis that may cause distinct shifts in the structure of the biofilm. Streptococci possibly facilitate the establishment of P. gingivalis into subgingival biofilms, while in their absence P. intermedia became more dominant and forms elongated chains.

  4. Microbiota in the oral subgingival biofilm is associated with obesity in adolescence.

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    Zeigler, Cecilia C; Persson, G Rutger; Wondimu, Biniyam; Marcus, Claude; Sobko, Tanja; Modéer, Thomas

    2012-01-01

    To test the hypothesis whether microbiota in oral biofilm is linked with obesity in adolescents we designed this cross-sectional study. Obese adolescents (n = 29) with a mean age of 14.7 years and normal weight subjects (n = 58) matched by age and gender were examined with respect to visible plaque index (VPI%) and gingival inflammation (bleeding on probing (BOP%)). Stimulated saliva was collected. They answered a questionnaire concerning medical history, medication, oral hygiene habits, smoking habits, and sociodemographic background. Microbiological samples taken from the gingival crevice was analyzed by checkerboard DNA-DNA hybridization technique. The sum of bacterial cells in subgingival biofilm was significantly associated with obesity (P obesity was not confounded by any of the studied variables (chronic disease, medication, VPI%, BOP%, flow rate of whole saliva, or meal frequency). Totally 23 bacterial species were present in approximately threefold higher amounts, on average, in obese subjects compared with normal weight controls. Of the Proteobacteria phylum, Campylobacter rectus and Neisseria mucosa were present in sixfold higher amounts among obese subjects. The association between obesity and sum of bacterial cells in oral subgingival biofilm indicates a possible link between oral microbiota and obesity in adolescents.

  5. Microbial diversity of supra- and subgingival biofilms on freshly colonized titanium implant abutments in the human mouth.

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    Heuer, W; Stiesch, M; Abraham, W R

    2011-02-01

    Supra- and subgingival biofilm formation is considered to be mainly responsible for early implant failure caused by inflammations of periimplant tissues. Nevertheless, little is known about the complex microbial diversity and interindividual similarities around dental implants. An atraumatic assessment was made of the diversity of microbial communities around titanium implants by single strand conformation polymorphism (SSCP) analysis of the 16S rRNA gene amplicons as well as subsequent sequence analysis. Samples of adherent supra- and subgingival periimplant biofilms were collected from ten patients. Additionally, samples of sulcusfluid were taken at titanium implant abutments and remaining teeth. The bacteria in the samples were characterized by SSCP and sequence analysis. A high diversity of bacteria varying between patients and within one patient at different locations was found. Bacteria characteristic for sulcusfluid and supra- and subgingival biofilm communities were identified. Sulcusfluid of the abutments showed higher abundance of Streptococcus species than from residual teeth. Prevotella and Rothia species frequently reported from the oral cavity were not detected at the abutments suggesting a role as late colonizers. Different niches in the human mouth are characterized by specific groups of bacteria. Implant abutments are a very valuable approach to study dental biofilm development in vivo.

  6. Long-term evaluation of the antimicrobial susceptibility and microbial profile of subgingival biofilms in individuals with aggressive periodontitis

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    Lourenço, Talita Gomes Baêta; Heller, Débora; do Souto, Renata Martins; Silva-Senem, Mayra Xavier e; Varela, Victor Macedo; Torres, Maria Cynesia Barros; Feres-Filho, Eduardo Jorge; Colombo, Ana Paula Vieira

    2015-01-01

    This study evaluates the antimicrobial susceptibility and composition of subgingival biofilms in generalized aggressive periodontitis (GAP) patients treated using mechanical/antimicrobial therapies, including chlorhexidine (CHX), amoxicillin (AMX) and metronidazole (MET). GAP patients allocated to the placebo (C, n = 15) or test group (T, n = 16) received full-mouth disinfection with CHX, scaling and root planning, and systemic AMX (500 mg)/MET (250 mg) or placebos. Subgingival plaque samples were obtained at baseline, 3, 6, 9 and 12 months post-therapy from 3–4 periodontal pockets, and the samples were pooled and cultivated under anaerobic conditions. The minimum inhibitory concentrations (MICs) of AMX, MET and CHX were assessed using the microdilution method. Bacterial species present in the cultivated biofilm were identified by checkerboard DNA-DNA hybridization. At baseline, no differences in the MICs between groups were observed for the 3 antimicrobials. In the T group, significant increases in the MICs of CHX (p < 0.05) and AMX (p < 0.01) were detected during the first 3 months; however, the MIC of MET decreased at 12 months (p < 0.05). For several species, the MICs significantly changed over time in both groups, i.e., Streptococci MICs tended to increase, while for several periodontal pathogens, the MICs diminished. A transitory increase in the MIC of the subgingival biofilm to AMX and CHX was observed in GAP patients treated using enhanced mechanical therapy with topical CHX and systemic AMX/MET. Both protocols presented limited effects on the cultivable subgingival microbiota. PMID:26273264

  7. Prevalence of Pseudomonas aeruginosa and Acinetobacter spp. in subgingival biofilm and saliva of subjects with chronic periodontal infection

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    Souto, Renata; Silva-Boghossian, Carina M.; Colombo, Ana Paula Vieira

    2014-01-01

    P. aeruginosa and Acinetobacter spp. are important pathogens associated with late nosocomial pneumonia in hospitalized and institutionalized individuals. The oral cavity may be a major source of these respiratory pathogens, particularly in the presence of poor oral hygiene and periodontal infection. This study investigated the prevalence of P. aeruginosa and Acinetobacter spp. in subgingival biofilm and saliva of subjects with periodontal disease or health. Samples were obtained from 55 periodontally healthy (PH) and 169 chronic periodontitis (CP) patients. DNA was obtained from the samples and detection of P. aeruginosa and Acinetobacter spp. was carried out by multiplex and nested PCR. P. aeruginosa and Acinetobacter spp. were detected in 40% and 45% of all samples, respectively. No significant differences in the distribution of these microorganisms between men and women, subgingival biofilm and saliva samples, patients ≤ 35 and > 35 years of age, and smokers and non-smokers were observed regardless periodontal status (p > 0.05). In contrast, the frequencies of P. aeruginosa and Acinetobacter spp. in saliva and biofilm samples were significantly greater in CP than PH patients (p oral microbiota of CP. Poor oral hygiene, smoking and the presence of P. aeruginosa are strongly associated with periodontitis. PMID:25242933

  8. Prevalence of Pseudomonas aeruginosa and Acinetobacter spp. in subgingival biofilm and saliva of subjects with chronic periodontal infection.

    Science.gov (United States)

    Souto, Renata; Silva-Boghossian, Carina M; Colombo, Ana Paula Vieira

    2014-01-01

    P. aeruginosa and Acinetobacter spp. are important pathogens associated with late nosocomial pneumonia in hospitalized and institutionalized individuals. The oral cavity may be a major source of these respiratory pathogens, particularly in the presence of poor oral hygiene and periodontal infection. This study investigated the prevalence of P. aeruginosa and Acinetobacter spp. in subgingival biofilm and saliva of subjects with periodontal disease or health. Samples were obtained from 55 periodontally healthy (PH) and 169 chronic periodontitis (CP) patients. DNA was obtained from the samples and detection of P. aeruginosa and Acinetobacter spp. was carried out by multiplex and nested PCR. P. aeruginosa and Acinetobacter spp. were detected in 40% and 45% of all samples, respectively. No significant differences in the distribution of these microorganisms between men and women, subgingival biofilm and saliva samples, patients ≤ 35 and > 35 years of age, and smokers and non-smokers were observed regardless periodontal status (p > 0.05). In contrast, the frequencies of P. aeruginosa and Acinetobacter spp. in saliva and biofilm samples were significantly greater in CP than PH patients (p Acinetobacter spp. are frequently detected in the oral microbiota of CP. Poor oral hygiene, smoking and the presence of P. aeruginosa are strongly associated with periodontitis.

  9. Microbial profile comparisons of saliva, pooled and site-specific subgingival samples in periodontitis patients

    DEFF Research Database (Denmark)

    Belstrøm, Daniel; Sembler-Møller, Maria Lynn; Grande, Maria Anastasia

    2017-01-01

    OBJECTIVES: The purpose of this study was to compare microbial profiles of saliva, pooled and site-specific subgingival samples in patients with periodontitis. We tested the hypotheses that saliva can be an alternative to pooled subgingival samples, when screening for presence of periopathogens....... DESIGN: Site specific subgingival plaque samples (n = 54), pooled subgingival plaque samples (n = 18) and stimulated saliva samples (n = 18) were collected from 18 patients with generalized chronic periodontitis. Subgingival and salivary microbiotas were characterized by means of HOMINGS (Human Oral...... to an AUC of 0.76 (sensitivity: 0.56, specificity: 0.94) in pooled subgingival samples. CONCLUSIONS: Site-specific presence of periodontal pathogens was detected with comparable accuracy in stimulated saliva samples and pooled subgingival plaque samples. Consequently, saliva may be a reasonable surrogate...

  10. Microbial profile comparisons of saliva, pooled and site-specific subgingival samples in periodontitis patients

    DEFF Research Database (Denmark)

    Belstrøm, Daniel; Sembler-Møller, Maria Lynn; Grande, Maria Anastasia

    2017-01-01

    . DESIGN: Site specific subgingival plaque samples (n = 54), pooled subgingival plaque samples (n = 18) and stimulated saliva samples (n = 18) were collected from 18 patients with generalized chronic periodontitis. Subgingival and salivary microbiotas were characterized by means of HOMINGS (Human Oral......OBJECTIVES: The purpose of this study was to compare microbial profiles of saliva, pooled and site-specific subgingival samples in patients with periodontitis. We tested the hypotheses that saliva can be an alternative to pooled subgingival samples, when screening for presence of periopathogens...... by pooled subgingival samples. Presence of Porphyromonas gingivalis, Treponema denticola, Prevotella intermedia, Filifactor alocis, Tannerella forsythia and Parvimona micra in site-specific subgingival samples were detected in saliva with an AUC of 0.79 (sensitivity: 0.61, specificity: 0.94), compared...

  11. Levels of Candidate Periodontal Pathogens in Subgingival Biofilm

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    Oliveira, R.R.D.S.; Fermiano, D.; Feres, M.; Figueiredo, L.C.; Teles, F.R.F.; Soares, G.M.S.; Faveri, M.

    2016-01-01

    In recent years, several new periodontal taxa have been associated with the etiology of periodontitis. A recent systematic review provides further support for the pathogenic role of 17 species/phylotypes. Thus, the aim of this study was to assess the prevalence and levels of these species in subjects with generalized chronic periodontitis (GChP; n = 30), generalized aggressive periodontitis (GAgP; n = 30), and periodontal health (PH; n = 30). All subjects underwent clinical and microbiological assessment. Nine subgingival plaque samples were collected from each subject and analyzed for their content of 20 bacterial species/phylotypes through the RNA-oligonucleotide quantification technique. Subjects from the GChP and GAgP groups presented the highest mean values for all clinical parameters in comparison with the PH group (P < 0.05). Subjects with GChP and GAgP showed significantly higher mean levels of Bacteroidetes sp. human oral taxon (HOT) 274, Fretibacterium sp. HOT 360, and TM7 sp. HOT 356 phylotypes, as well as higher mean levels of Filifactor alocis, Fretibacterium fastidiosum, Porphyromonas gingivalis, Tannerella forsythia, and Selenomonas sputigena species than PH subjects (P < 0.05). GAgP subjects presented higher mean levels of TM7 sp. HOT 356 and F. alocis than GChP subjects (P < 0.05). A significantly higher mean prevalence of Bacteroidales sp. HOT 274, Desulfobulbus sp. HOT 041, Fretibacterium sp. HOT 360, and Fretibacterium sp. HOT 362 was found in subjects with GChP and GAgP than in PH subjects. Mean levels of P. gingivalis (r = 0.68), T. forsythia (r = 0.62), F. alocis (r = 0.51, P = 0.001), and Fretibacterium sp. HOT 360 (r = 0.41) were correlated with pocket depth (P < 0.001). In conclusion, Bacteroidales sp. HOT 274, Desulfobulbus sp. HOT 041, Fretibacterium sp. HOT 360, Fretibacterium sp. HOT 362, and TM7 sp. HOT 356 phylotypes, in addition to F. alocis, F. fastidiosum, and S. sputigena, seem to be associated with periodontitis, and their role

  12. Sampling Modification Effects in the Subgingival Microbiome Profile of Healthy Children.

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    Santigli, Elisabeth; Trajanoski, Slave; Eberhard, Katharina; Klug, Barbara

    2016-01-01

    Background: Oral microbiota are considered major players in the development of periodontal diseases. Thorough knowledge of intact subgingival microbiomes is required to elucidate microbial shifts from health to disease. Aims: This comparative study investigated the subgingival microbiome of healthy children, possible inter- and intra-individual effects of modified sampling, and basic comparability of subgingival microprints. Methods: In five 10-year-old children, biofilm was collected from the upper first premolars and first molars using sterilized, UV-treated paper-points inserted into the subgingival sulcus at eight sites. After supragingival cleaning using an electric toothbrush and water, sampling was performed, firstly, excluding (Mode A) and, secondly, including (Mode B) cleansing with sterile cotton pellets. DNA was extracted from the pooled samples, and primers targeting 16S rRNA hypervariable regions V5 and V6 were used for 454-pyrosequencing. Wilcoxon signed rank test and t -test were applied to compare sampling modes. Principal coordinate analysis (PCoA) and average agglomerative hierarchical clustering were calculated with unweighted UniFrac distance matrices. Sample grouping was tested with permutational MANOVA (Adonis). Results: Data filtering and quality control yielded 67,218 sequences with an average sequence length of 243bp (SD 6.52; range 231-255). Actinobacteria (2.8-24.6%), Bacteroidetes (9.2-25.1%), Proteobacteria (4.9-50.6%), Firmicutes (16.5-57.4%), and Fusobacteria (2.2-17.1%) were the five major phyla found in all samples. Differences in microbial abundances between sampling modes were not evident. High sampling numbers are needed to achieve significance for rare bacterial phyla. Samples taken from one individual using different sampling modes were more similar to each other than to other individuals' samples. PCoA and hierarchical clustering showed a grouping of the paired samples. Permutational MANOVA did not reveal sample grouping by

  13. Sampling Modification Effects in the Subgingival Microbiome Profile of Healthy Children

    Science.gov (United States)

    Santigli, Elisabeth; Trajanoski, Slave; Eberhard, Katharina; Klug, Barbara

    2017-01-01

    Background: Oral microbiota are considered major players in the development of periodontal diseases. Thorough knowledge of intact subgingival microbiomes is required to elucidate microbial shifts from health to disease. Aims: This comparative study investigated the subgingival microbiome of healthy children, possible inter- and intra-individual effects of modified sampling, and basic comparability of subgingival microprints. Methods: In five 10-year-old children, biofilm was collected from the upper first premolars and first molars using sterilized, UV-treated paper-points inserted into the subgingival sulcus at eight sites. After supragingival cleaning using an electric toothbrush and water, sampling was performed, firstly, excluding (Mode A) and, secondly, including (Mode B) cleansing with sterile cotton pellets. DNA was extracted from the pooled samples, and primers targeting 16S rRNA hypervariable regions V5 and V6 were used for 454-pyrosequencing. Wilcoxon signed rank test and t-test were applied to compare sampling modes. Principal coordinate analysis (PCoA) and average agglomerative hierarchical clustering were calculated with unweighted UniFrac distance matrices. Sample grouping was tested with permutational MANOVA (Adonis). Results: Data filtering and quality control yielded 67,218 sequences with an average sequence length of 243bp (SD 6.52; range 231–255). Actinobacteria (2.8–24.6%), Bacteroidetes (9.2–25.1%), Proteobacteria (4.9–50.6%), Firmicutes (16.5–57.4%), and Fusobacteria (2.2–17.1%) were the five major phyla found in all samples. Differences in microbial abundances between sampling modes were not evident. High sampling numbers are needed to achieve significance for rare bacterial phyla. Samples taken from one individual using different sampling modes were more similar to each other than to other individuals' samples. PCoA and hierarchical clustering showed a grouping of the paired samples. Permutational MANOVA did not reveal sample

  14. Oral Biofilm Sampling for Microbiome Analysis in Healthy Children.

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    Santigli, Elisabeth; Koller, Martin; Klug, Barbara

    2017-12-31

    Oral biofilm and its molecular analysis provide a basis for investigating various dental research and clinical questions. Knowledge of biofilm composition leads to a better understanding of cariogenic and periopathogenic mechanisms. Microbial changes taking place in the oral cavity during childhood are of interest for several reasons. The evolution of the child oral microbiota and shifts in its composition need to be analyzed further to understand and possibly prevent the onset of disease. At the same time, advanced knowledge of the natural composition of oral biofilm is needed. Early stages of caries-free permanent dentition with healthy gums provide a widely unaffected subgingival habitat that can serve as an in situ baseline for studying features of oral health and disease. Analysis of children's oral biofilm during different stages in life is thus an important theme in the field. Modern molecular analysis methods can provide comprehensive information about the bacterial diversity of such biofilms. To enable microbiota data comparison, it is important to standardize each step in the procedure for molecular data generation. This procedure spans from clinical sampling, Next Generation Sequencing (NGS), bioinformatic data processing, to taxonomic interpretation. One of the most critical factors here is biofilm sampling. Sampling in children is even more challenging in particular due to limited space in subgingival areas. We thus focus on the use of paper points for subgingival sampling. This article provides a detailed protocol for oral biofilm sampling of the subgingival sulcus, the mucosa, and saliva in children.

  15. Microbial dynamics during conversion from supragingival to subgingival biofilms in an in vitro model.

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    Thurnheer, T; Bostanci, N; Belibasakis, G N

    2016-04-01

    The development of dental caries and periodontal diseases result from distinct shifts in the microbiota of the tooth-associated biofilm. This in vitro study aimed to investigate changes in biofilm composition and structure, during the shift from a 'supragingival' aerobic profile to a 'subgingival' anaerobic profile. Biofilms consisting of Actinomyces oris, Candida albicans, Fusobacterium nucleatum, Streptococcus oralis, Streptococcus mutans and Veillonella dispar were aerobically grown in saliva-containing medium on hydroxyapatite disks. After 64 h, Campylobacter rectus, Prevotella intermedia and Streptococcus anginosus were further added along with human serum, while culture conditions were shifted to microaerophilic. After 96 h, Porphyromonas gingivalis, Tannerella forsythia and Treponema denticola were finally added and the biofilm was grown anaerobically for another 64 h. At the end of each phase, biofilms were harvested for species-specific quantification and localization. Apart from C. albicans, all other species gradually increased during aerobic and microaerophilic conditions, but remained steady during anaerobic conditions. Biofilm thickness was doubled during the microaerophilic phase, but remained steady throughout the anaerobic phase. Extracellular polysaccharide presence was gradually reduced throughout the growth period. Biofilm viability was reduced during the microaerophilic conversion, but was recovered during the anaerobic phase. This in vitro study has characterized the dynamic structural shifts occurring in an oral biofilm model during the switch from aerobic to anaerobic conditions, potentially modeling the conversion of supragingival to subgingival biofilms. Within the limitations of this experimental model, the findings may provide novel insights into the ecology of oral biofilms. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  16. Advancement of the 10-species subgingival Zurich biofilm model by examining different nutritional conditions and defining the structure of the in vitro biofilms.

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    Ammann, Thomas W; Gmür, Rudolf; Thurnheer, Thomas

    2012-10-05

    Periodontitis is caused by a highly complex consortium of bacteria that establishes as biofilms in subgingival pockets. It is a disease that occurs worldwide and its consequences are a major health concern. Investigations in situ are not possible and the bacterial community varies greatly between patients and even within different loci. Due to the high complexity of the consortium and the availability of samples, a clear definition of the pathogenic bacteria and their mechanisms of pathogenicity are still not available. In the current study we addressed the need of a defined model system by advancing our previously described subgingival biofilm model towards a bacterial composition that reflects the one observed in diseased sites of patients and analysed the structure of these biofilms. We further developed the growth media by systematic variation of key components resulting in improved stability and the firm establishment of spirochetes in the 10-species subgingival Zurich biofilm model. A high concentration of heat-inactivated human serum allowed the best proliferation of the used species. Therefore we further investigated these biofilms by analysing their structure by confocal laser scanning microscopy following fluorescence in situ hybridisation. The species showed mutual interactions as expected from other studies. The abundances of all organisms present in this model were determined by microscopic counting following species-specific identification by both fluorescence in situ hybridisation and immunofluorescence. The newly integrated treponemes were the most abundant organisms. The use of 50% of heat-inactivated human serum used in the improved growth medium resulted in significantly thicker and more stable biofilms, and the quantitative representation of the used species represents the in vivo community of periodontitis patients much closer than in biofilms grown in the two media with less or no human serum. The appearance of T. denticola, P. gingivalis, and

  17. Microbial diversity of the supra- and subgingival biofilm of healthy individuals after brushing with chlorhexidine- or silver-coated toothbrush bristles.

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    do Nascimento, Cássio; Paulo, Diana Ferreira; Pita, Murillo Sucena; Pedrazzi, Vinícius; de Albuquerque Junior, Rubens Ferreira

    2015-02-01

    Nanoparticulate silver has recently been reported as an effective antimicrobial agent. The aim of this clinical study was to investigate the potential changes on the oral microbiota of healthy individuals after controlled brushing with chlorhexidine- or silver-coated toothbrush bristles. Twenty-four healthy participants were enrolled in this investigation and randomly submitted to 3 interventions. All the participants received, in a crossover format, the following toothbrushing interventions: (i) chlorhexidine-coated bristles, (ii) silver-coated bristles, and (iii) conventional toothbrush (Control). All the interventions had a duration of 30 days. The DNA checkerboard hybridization method was used to identify and quantify up to 43 microbial species colonizing the supra- and subgingival biofilm. The supragingival samples presented higher genome counts than the subgingival samples (p < 0.0001). The total genome counts from the Control group showed the highest values, followed by the silver and chlorhexidine groups (p < 0.0001). After 4 weeks of brushing, the silver-coated and chlorhexidine-coated bristles were capable of reducing or maintaining lower levels of the bacterial counts of the putative periodontal pathogens Tanerella forsythia, Treponema denticola, and Porphyromonas gingivalis. Other major periodontal pathogens, such as Prevotella intermedia, Fusobacterium nucleatum, Prevotella nigrescens, and Parvimonas micra, were also detected at lower levels. The toothbrush bristles impregnated with silver nanoparticles reduced the total and individual genome count in the supra- and subgingival biofilm after 4 weeks of brushing. Chlorhexidine was not effective in reducing the total genome counts in both supra- or subgingival biofilm after 4 weeks of brushing. Chlorhexidine reduced the individual genome counts in the supragingival biofilm for most of the target species, including putative periodontal pathogens.

  18. Photoinactivation Using Visible Light Plus Water-Filtered Infrared-A (vis+wIRA and Chlorine e6 (Ce6 eradicates Planktonic Periodontal Pathogens and Subgingival Biofilms

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    Ali Al-Ahmad

    2016-11-01

    Full Text Available Alternative treatment methods for pathogens and microbial biofilms are required due to the widespread rise in antibiotic resistance. Antimicrobial photodynamic therapy (aPDT has recently gained attention as a novel method to eradicate pathogens. The aim of this study was to evaluate the antimicrobial effects of a novel aPDT method using visible light (vis and water infiltrated infrared A (wIRA in combination with chlorine e6 (Ce6 against different periodontal pathogens in planktonic form and within in situ subgingival oral biofilms. Eight different periodontal pathogens were exposed to aPDT using vis+wIRA and 100 µg/ml Ce6 in planktonic culture. Additionally, pooled subgingival dental biofilm was also treated by aPDT and the number of viable cells determined as colony forming units (CFU. Live/dead staining was used in combination with confocal laser scanning microscopy (CLSM to visualize and quantify antimicrobial effects within the biofilm samples. Untreated negative controls as well as 0.2 % chlorhexidine (CHX-treated positive controls were used. All eight tested periodontal pathogens including Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Eikenella corrodens, Actinomyces odontolyticus, Fusobacterium nucleatum, Parvimonas micra, Slackia exigua and Atopopium rimae and the aPDT-treated subgingival biofilm were eliminated over the ranges of 3.43 - 8.34 and 3.91 - 4.28 log10 CFU in the log10 scale, respectively. Thus, aPDT showed bactericidal effects on the representative pathogens as well as on the in situ subgingival biofilm. The live/dead staining also revealed a significant reduction (33.45 % of active cells within the aPDT-treated subgingival biofilm. Taking the favorable tissue healing effects of vis+wIRA into consideration, the significant antimicrobial effects revealed in this study highlight the potential of aPDT using this light source in combination with Ce6 as an adjunctive method to treat periodontitis as well as

  19. Efficacy of a triclosan formula in controlling early subgingival biofilm formation: a randomized trial

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    Ernesto ANDRADE

    2015-01-01

    Full Text Available The aim of this study was to determine the efficacy of rinses with slurries of a dentifrice containing triclosan (TCS, as compared with rinses with slurries from a control dentifrice, in controlling early subgingival biofilm formation. A double-blind, randomized and cross-over clinical trial was designed, and 26 dental students were included. In the first period, participants were randomized to rinse with a TCS slurry or a control slurry, in a 12 h interval, and to refrain from mechanical cleaning. A Plaque Free Zone Index was assessed at 24 h, 48 h, 72 h and 96 h. After a washout period of 10 days, the second experimental period was conducted, following the same protocol as the first period, except that the slurry groups were switched. Use of the TCS slurry resulted in a significantly higher percentage of plaque-free surfaces, both at 24 h and at 72 h (p < 0.01. In the of 48-72 h interval, the triclosan slurry showed a lower percentage of sites converted to a score of 2 (38.1% for the testversus 40% for the control product, p = 0.015. In conclusion, rinsing with slurries of dentifrice containing TCS retards the down growth of bacterial biofilms from the supra- to the subgingival environment.

  20. Detection of Mogibacterium timidum in subgingival biofilm of aggressive and non-diabetic and diabetic chronic periodontitis patients

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    Renato Corrêa Viana Casarin

    2012-09-01

    Full Text Available The aim of the present study was to evaluate the frequency of detection of Mogibacterium timidum in subgingival samples of subjects with generalized aggressive periodontitis (GAgP and uncontrolled diabetic and non-diabetic subjects with generalized chronic periodontitis (GChP. 48 patients with GAgP, 50 non-diabetic and 39 uncontrolled (glycated hemoglobin >7% type 2 diabetic subjects with GChP were enrolled in this study. Subgingival biofilm were collected from deep pockets (probing depth > 7 mm. After DNA extraction, M. timidum was detected by Nested Polymerase Chain Reaction and chi-square test was used to data analysis (p>0.05. There were no differences in the frequency of detection of M. timidum between subjects with GAgP (35% and non-diabetic subjects with GChP (40% (p>0.05. The frequency of detection of M. timidum was significantly higher in deep pockets of diabetic subjects with GChP (56% when compared to GAgP (p0.05. The frequency of detection of M. timidum was higher in subjects GChP presenting uncontrolled type 2 diabetes mellitus, when compared to GAgP subjects.

  1. Gingival changes during pregnancy: II. Influence of hormonal variations on the subgingival biofilm.

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    Carrillo-de-Albornoz, Ana; Figuero, Elena; Herrera, David; Bascones-Martínez, Antonio

    2010-03-01

    To determine whether the exacerbated gingival inflammation that develops in pregnant women is related to a change in the subgingival biofilm induced by the increase in hormone levels during pregnancy. This open cohort study included 48 pregnant and 28 non-pregnant women without periodontitis. Pregnant women were evaluated in the first, second and third trimester and at 3 months after delivery. Non-pregnant women were evaluated twice, with a 6-month interval, assessing microbiological, clinical and hormonal variables at each visit. Total anaerobic counts and frequency of detection and proportions were calculated. The Friedman test with the Bonferroni correction was used for intra-group comparisons and Mann-Whitney U-tests for inter-group assessment. Correlations were analysed by means of Spearman's rank correlation coefficient. Proportions of the subgingival periodontal pathogens did not differ throughout pregnancy, although significant differences were found for all the pathogens after delivery. Porphyromonas gingivalis-positive patients presented an increase in gingival inflammation (phormone levels and P. gingivalis and Prevotella intermedia. Qualitative differences in periodontal pathogens were found from pregnancy to post-partum. Patients harbouring P. gingivalis presented and increased gingival inflammatory status.

  2. Microbial diversity of supra- and subgingival biofilms on freshly colonized titanium implant abutments in the human mouth

    OpenAIRE

    2010-01-01

    Abstract Supra- and subgingival biofilm formation is considered to be mainly responsible for early implant failure caused by inflammations of periimplant tissues. Nevertheless, little is known about the complex microbial diversity and interindividual similarities around dental implants. An atraumatic assessment was made of the diversity of microbial communities around titanium implants by single strand conformation polymorphism (SSCP) analysis of the 16S rRNA gene amplicons as well...

  3. Detection and comparison of Selenomonas sputigena in subgingival biofilms in chronic and aggressive periodontitis patients

    Directory of Open Access Journals (Sweden)

    Disha Nagpal

    2016-01-01

    Full Text Available Background: With the advent of DNA-based culture-independent techniques, a constantly growing number of Selenomonas phylotypes have been detected in patients with destructive periodontal diseases. However, the prevalence levels that have been determined in different studies vary considerably. Aim: The present study was undertaken to detect and compare the presence of Selenomonas sputigena in the subgingival plaque samples from generalized aggressive periodontitis (GAP, chronic generalized periodontitis, and periodontally healthy patients using conventional polymerase chain reaction (PCR technique. Materials and Methods: A total of 90 patients were categorized as periodontally healthy individuals (Group I, n = 30, chronic generalized periodontitis (Group II, n = 30, and GAP (Group III, n = 30. The clinical parameters were recorded and subgingival plaque samples were collected. These were then subjected to conventional PCR analysis.Statistical Analysis Used: Kruskal–Wallis ANOVA test was used for multiple group comparisons followed by Mann–Whitney U-test for pairwise comparison. Results: On comparison between three groups, all the clinical parameters were found to be statistically highly significant. Comparing Groups I-II and I-III, the difference in detection was found to be statistically highly significant whereas in Groups II-III, it was statistically nonsignificant. On comparison of S. sputigena detected and undetected patients to clinical parameters in various study groups, the difference was found to be nonsignificant. Conclusion:S. sputigena was found to be significantly associated with chronic and aggressive periodontitis. Although the difference in its detection frequency in both groups was statistically nonsignificant when compared clinically, S. sputigena was more closely associated with the GAP.

  4. Co-localized or randomly distributed? Pair cross correlation of in vivo grown subgingival biofilm bacteria quantified by digital image analysis.

    Directory of Open Access Journals (Sweden)

    Claudia Schillinger

    Full Text Available The polymicrobial nature of periodontal diseases is reflected by the diversity of phylotypes detected in subgingival plaque and the finding that consortia of suspected pathogens rather than single species are associated with disease development. A number of these microorganisms have been demonstrated in vitro to interact and enhance biofilm integration, survival or even pathogenic features. To examine the in vivo relevance of these proposed interactions, we extended the spatial arrangement analysis tool of the software daime (digital image analysis in microbial ecology. This modification enabled the quantitative analysis of microbial co-localization in images of subgingival biofilm species, where the biomass was confined to fractions of the whole-image area, a situation common for medical samples. Selected representatives of the disease-associated red and orange complexes that were previously suggested to interact with each other in vitro (Tannerella forsythia with Fusobacterium nucleatum and Porphyromonas gingivalis with Prevotella intermedia were chosen for analysis and labeled with specific fluorescent probes via fluorescence in situ hybridization. Pair cross-correlation analysis of in vivo grown biofilms revealed tight clustering of F. nucleatum/periodonticum and T. forsythia at short distances (up to 6 µm with a pronounced peak at 1.5 µm. While these results confirmed previous in vitro observations for F. nucleatum and T. forsythia, random spatial distribution was detected between P. gingivalis and P. intermedia in the in vivo samples. In conclusion, we successfully employed spatial arrangement analysis on the single cell level in clinically relevant medical samples and demonstrated the utility of this approach for the in vivo validation of in vitro observations by analyzing statistically relevant numbers of different patients. More importantly, the culture-independent nature of this approach enables similar quantitative analyses for "as

  5. Co-localized or randomly distributed? Pair cross correlation of in vivo grown subgingival biofilm bacteria quantified by digital image analysis.

    Science.gov (United States)

    Schillinger, Claudia; Petrich, Annett; Lux, Renate; Riep, Birgit; Kikhney, Judith; Friedmann, Anton; Wolinsky, Lawrence E; Göbel, Ulf B; Daims, Holger; Moter, Annette

    2012-01-01

    The polymicrobial nature of periodontal diseases is reflected by the diversity of phylotypes detected in subgingival plaque and the finding that consortia of suspected pathogens rather than single species are associated with disease development. A number of these microorganisms have been demonstrated in vitro to interact and enhance biofilm integration, survival or even pathogenic features. To examine the in vivo relevance of these proposed interactions, we extended the spatial arrangement analysis tool of the software daime (digital image analysis in microbial ecology). This modification enabled the quantitative analysis of microbial co-localization in images of subgingival biofilm species, where the biomass was confined to fractions of the whole-image area, a situation common for medical samples. Selected representatives of the disease-associated red and orange complexes that were previously suggested to interact with each other in vitro (Tannerella forsythia with Fusobacterium nucleatum and Porphyromonas gingivalis with Prevotella intermedia) were chosen for analysis and labeled with specific fluorescent probes via fluorescence in situ hybridization. Pair cross-correlation analysis of in vivo grown biofilms revealed tight clustering of F. nucleatum/periodonticum and T. forsythia at short distances (up to 6 µm) with a pronounced peak at 1.5 µm. While these results confirmed previous in vitro observations for F. nucleatum and T. forsythia, random spatial distribution was detected between P. gingivalis and P. intermedia in the in vivo samples. In conclusion, we successfully employed spatial arrangement analysis on the single cell level in clinically relevant medical samples and demonstrated the utility of this approach for the in vivo validation of in vitro observations by analyzing statistically relevant numbers of different patients. More importantly, the culture-independent nature of this approach enables similar quantitative analyses for "as

  6. Rapid identification of oral Actinomyces species cultivated from subgingival biofilm by MALDI-TOF-MS

    Science.gov (United States)

    Stingu, Catalina S.; Borgmann, Toralf; Rodloff, Arne C.; Vielkind, Paul; Jentsch, Holger; Schellenberger, Wolfgang; Eschrich, Klaus

    2015-01-01

    Background Actinomyces are a common part of the residential flora of the human intestinal tract, genitourinary system and skin. Isolation and identification of Actinomyces by conventional methods is often difficult and time consuming. In recent years, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) has become a rapid and simple method to identify bacteria. Objective The present study evaluated a new in-house algorithm using MALDI-TOF-MS for rapid identification of different species of oral Actinomyces cultivated from subgingival biofilm. Design Eleven reference strains and 674 clinical strains were used in this study. All the strains were preliminarily identified using biochemical methods and then subjected to MALDI-TOF-MS analysis using both similarity-based analysis and classification methods (support vector machine [SVM]). The genotype of the reference strains and of 232 clinical strains was identified by sequence analysis of the 16S ribosomal RNA (rRNA). Results The sequence analysis of the 16S rRNA gene of all references strains confirmed their previous identification. The MALDI-TOF-MS spectra obtained from the reference strains and the other clinical strains undoubtedly identified as Actinomyces by 16S rRNA sequencing were used to create the mass spectra reference database. Already a visual inspection of the mass spectra of different species reveals both similarities and differences. However, the differences between them are not large enough to allow a reliable differentiation by similarity analysis. Therefore, classification methods were applied as an alternative approach for differentiation and identification of Actinomyces at the species level. A cross-validation of the reference database representing 14 Actinomyces species yielded correct results for all species which were represented by more than two strains in the database. Conclusions Our results suggest that a combination of MALDI-TOF-MS with powerful

  7. Rapid identification of oral Actinomyces species cultivated from subgingival biofilm by MALDI-TOF-MS

    Directory of Open Access Journals (Sweden)

    Catalina S. Stingu

    2015-01-01

    Full Text Available Background: Actinomyces are a common part of the residential flora of the human intestinal tract, genitourinary system and skin. Isolation and identification of Actinomyces by conventional methods is often difficult and time consuming. In recent years, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS has become a rapid and simple method to identify bacteria. Objective: The present study evaluated a new in-house algorithm using MALDI-TOF-MS for rapid identification of different species of oral Actinomyces cultivated from subgingival biofilm. Design: Eleven reference strains and 674 clinical strains were used in this study. All the strains were preliminarily identified using biochemical methods and then subjected to MALDI-TOF-MS analysis using both similarity-based analysis and classification methods (support vector machine [SVM]. The genotype of the reference strains and of 232 clinical strains was identified by sequence analysis of the 16S ribosomal RNA (rRNA. Results: The sequence analysis of the 16S rRNA gene of all references strains confirmed their previous identification. The MALDI-TOF-MS spectra obtained from the reference strains and the other clinical strains undoubtedly identified as Actinomyces by 16S rRNA sequencing were used to create the mass spectra reference database. Already a visual inspection of the mass spectra of different species reveals both similarities and differences. However, the differences between them are not large enough to allow a reliable differentiation by similarity analysis. Therefore, classification methods were applied as an alternative approach for differentiation and identification of Actinomyces at the species level. A cross-validation of the reference database representing 14 Actinomyces species yielded correct results for all species which were represented by more than two strains in the database. Conclusions: Our results suggest that a combination of MALDI

  8. Presencia de Porphyromonas gingivalis, Tannerella forsythia, Treponema denticola y Aggregatibacter actinomycetemcomitans en el biofilm subgingival de pacientes diabéticos tipo 2: estudio transversal Presence of Porphyromonas gingivalis, Tannerella forsythia, Treponema denticola and Aggregatibacter actinomycetemcomitans in the subgingival biofilm of diabetic mellitus 2 patients: a cross sectional study

    OpenAIRE

    AJ Quintero; P Prada; CM Inostroza; Chaparro,A; AF Sanz; VL Ramírez; HC Morales

    2011-01-01

    Antecedentes: La investigación de la microflora subgingival en pacientes diabéticos tipo 2 con periodontitis ha presentado resultados contradictorios. Objetivo: Determinar la presencia de Porphyromonas gingivalis, Tannerella forshytia, Treponema denticola y Aggregatibacter actinomycetemcomitans, en el biofilm subgingival de pacientes diabéticos tipo 2 y relacionarlo con el grado de control metabólico. Método: Estudio descriptivo transversal, en el cual se analizaron 23 pacientes diabéticos de...

  9. Comparison of real-time PCR and culture for detection of Porphyromonas gingivalis in subgingival plaque samples

    NARCIS (Netherlands)

    Boutaga, Khalil; van Winkelhoff, Arie Jan; Vandenbroucke-Grauls, Christina M. J. E.; Savelkoul, Paul H. M.

    2003-01-01

    Porphyromonas gingivalis is a major pathogen in destructive periodontal disease in humans. Detection and quantification of this microorganism are relevant for diagnosis and treatment planning. The prevalence and quantity of P. gingivalis in subgingival plaque samples of periodontitis patients were

  10. Prevalence of "non-oral" pathogenic bacteria in subgingival biofilm of subjects with chronic periodontitis Prevalência de bactérias patogênicas "não-orais" no biofilme dental subgengival de pacientes com periodontite crônica

    National Research Council Canada - National Science Library

    Renata Souto; Arnaldo Feitosa B. de Andrade; Milton Uzeda; Ana Paula Vieira Colombo

    2006-01-01

    .... Therefore, the purpose of this study was to determine the prevalence and levels of pathogenic bacteria in the subgingival biofilm of chronic periodontitis lesions and healthy periodontal sites using...

  11. The profile of Porphyromonas gingivalis kgp biotype and fimA genotype mosaic in subgingival plaque samples.

    Science.gov (United States)

    Nadkarni, Mangala A; Chhour, Kim-Ly; Chapple, Cheryl C; Nguyen, Ky-Anh; Hunter, Neil

    2014-12-01

    Combined analysis of allelic variation of the virulence-associated, strain-specific lys-gingipain gene (kgp) and major fimbrial gene (fimA) of Porphyromonas gingivalis was undertaken in 116 subgingival plaque samples to understand the kgp biotype and fimA genotype profile in a subject-specific manner. Allelic variation in the polyadhesin domain of kgp from P. gingivalis strains 381 (ATCC 33277), HG66 and W83 generated four isoforms corresponding to four biotypes of P. gingivalis. Similarly, variation in the fimA subunit of the fimA gene cluster of P. gingivalis resulted in six fimA genotypes. Strain-specific differential PCR was performed for kgp and fimA using DNA isolated from subgingival plaque samples. Our findings demonstrate that all of the P. gingivalis kgp biotypes detected in this study were predominantly associated with the fimA II genotype. Dominance of kgp biotypes 381 or HG66 combined with fimA II fimbriae could imply an adaptive strategy by P. gingivalis to generate the fittest strains for survival in the host environment. © 2014 Federation of European Microbiological Societies. Published by John Wiley & Sons Ltd. All rights reserved.

  12. Detection of EBV, CMV and HSV-1 in subgingival samples of HIV positive and negative patients with chronic periodontitis.

    Directory of Open Access Journals (Sweden)

    Laura Escalona

    2016-06-01

    Full Text Available Objective: To detect the presence of infection by EBV (Epstein-Barr Virus, CMV (Cytomegalovirus and HSV-1 (Herpes Simplex Virus type 1 in subgingival samples from HIV- positive patients under HAART (High Activity Antiretroviral Therapy, HIV- positive patients without HAART, HIV-negative patients with chronic periodontitis and healthy controls. Methodology: Crevicular fluid samples of 11 HIV+ patients on therapy were evaluated, 6 without antiretroviral therapy, 7 HIV- negative subjects with chronic periodontitis and 7 periodontally-healthy controls. PI (Plaque index, GI (Gingival Index, PD (probing depth and CAL (Clinical Attachment Loss were registered at six sites per each tooth in all teeth and subgingival plaque samples of a tooth were collected per quadrant. Nested PCR was used to detect EBV and endpoint PCR to detect infection by CMV and HSV-1. Results: Clinical parameters showed statistically significant differences between HIV-positive patients and subjects with chronic periodontitis compared with the control group (p<0.05. DNA of EBV was detected mainly in HIV-positive patients under HAART, 91% (10/11. DNA of CMV was detected mainly in patients without HAART, 67% (4/6, while HSV-1 was observed in 27% (3/11 of patients under HAART. In the control group no virus was detected. Coinfection was observed in 50% of HIV patients without HAART, 36% of HIV patients with HAART and 14% of HIV-negative with chronic periodontitis. Conclusion: Viral infection was prevalent in HIV patients under HAART and EBV was the primary viral infection detected in HIV-positive patients with chronic periodontitis.

  13. Presencia de Porphyromonas gingivalis, Tannerella forsythia, Treponema denticola y Aggregatibacter actinomycetemcomitans en el biofilm subgingival de pacientes diabéticos tipo 2: estudio transversal Presence of Porphyromonas gingivalis, Tannerella forsythia, Treponema denticola and Aggregatibacter actinomycetemcomitans in the subgingival biofilm of diabetic mellitus 2 patients: a cross sectional study

    Directory of Open Access Journals (Sweden)

    AJ Quintero

    2011-08-01

    Full Text Available Antecedentes: La investigación de la microflora subgingival en pacientes diabéticos tipo 2 con periodontitis ha presentado resultados contradictorios. Objetivo: Determinar la presencia de Porphyromonas gingivalis, Tannerella forshytia, Treponema denticola y Aggregatibacter actinomycetemcomitans, en el biofilm subgingival de pacientes diabéticos tipo 2 y relacionarlo con el grado de control metabólico. Método: Estudio descriptivo transversal, en el cual se analizaron 23 pacientes diabéticos derivados consecutivamente del Policlínico de Especialidades de la Universidad de los Andes. Previo consentimiento informado, se realizó un examen clínico periodontal que incluyó mediciones de profundidad al sondaje, nivel de inserción clínica y sangrado gingival. Fueron clasificados según severidad de periodontitis y control metabólico de la diabetes determinado por un promedio de 3 exámenes de hemoglobina glicosilada. La detección microbiológica se realizó mediante la técnica de reacción en cadena de la polimerasa. Resultados: En el grupo de pacientes estudiados, Treponema denticola y Tannerella forsythia fueron las bacterias más prevalentes (65.2%, seguida por Porphyromonas gingivalis (17.3% y Aggregatibacter actinomycetemcomitans (13%. Los pacientes con peor control glicémico tuvieron una mayor presencia de Treponema denticola, Tannerella forsythia, Porphyromonas gingivalis y Agreggatibacter actinomycetemcomitans y un aumento en el índice de sangrado al sondaje. Conclusiones: En el grupo de pacientes diabéticos estudiado, las bacterias más prevalentes fueron Treponema denticola y Tannerella forsythia. Los pacientes diabéticos tipo 2 con moderado y mal control glicémico presentaron mayor presencia de los microorganismos estudiados, comparado con los grupos con mejores niveles de control glicémico.Background: The investigation of subgingival microflora in type 2 diabetic patients with periodontitis presented conflicting results

  14. Effect of cigarette smoking on subgingival bacteria in healthy subjects and patients with chronic periodontitis.

    Science.gov (United States)

    Karasneh, Jumana A; Al Habashneh, Rola A; Marzouka, Nour Aldain S; Thornhill, Martin H

    2017-03-21

    Cigarette smoking is known to increase the risk of periodontal destruction and developing chronic periodontitis (CP). It is also reported to affect the subgingival bacterial profile among CP patients. However, studies on the effect of smoking on the bacterial profile among healthy subjects are still limited. Therefore, the aim of this study was to investigate the impact of smoking on the subgingival bacterial profile in both healthy adults and CP patients. Subgingival plaque samples were collected from CP patients (30 nonsmokers and 9 smokers) and healthy subjects (37 non-smokers and 18 smokers). Genomic DNA was extracted and 25 bacterial species were detected using PCR of 16S rRNA. Comparing smokers to non-smokers from each group was conducted using chi2 and binary logistic regression analysis. After correcting for confounding factors, the odds of having Slackia exigua, Selenomonas sputigena and Campylobacter rectus was higher among healthy smokers (ORadj = 10.1, 6.62 and 5.62 respectively). While for CP group, the highest odds were observed for Treponema amylovorum, Treponema medium, Slackia exigua and Treponema vincentii (ORadj = 20.7, 7.97, 6.37 and 5.37 respectively) and the increase in Treponema amylovorum was statistically significant (p = 0.05). Smoking affects the subgingival bacterial profile in healthy individuals and is responsible for the depletion of beneficial bacteria and the increase in periodontopathogenic bacteria. In the CP patient group, our study suggests that subgingival bacteria (particularly Treponema species) make a more substantial contribution in the etiology of CP among non-smokers. Further studies using a larger sample set and more sensitive and quantitative techniques (such as real -time PCR) are needed to enhance our understanding of the exact effect of smoking on subgingival biofilm.

  15. Comparison of subgingival bacterial sampling with oral lavage for detection and quantification of periodontal pathogens by real-time polymerase chain reaction

    NARCIS (Netherlands)

    Boutaga, Khalil; Savelkoul, Paul H. M.; Winkel, Edwin G.; van Winkelhoff, Arie J.

    Background: Saliva has been studied for the presence of subgingival pathogens in periodontitis patients. With the anaerobic culture technique, the discrepancy between salivary recovery and subgingival presence has been significant, which makes this approach not suitable for practical use in the

  16. Medición de cambios cuantitativos de la microbiota subgingival posterior a la remoción de placa bacteriana supragingival Measurement of quantitative changes of the microbiota subgingival after to removal of bacterial plaque supragingival

    Directory of Open Access Journals (Sweden)

    C Godoy

    2010-04-01

    possible that the microorganisms responsible for the origin and progression of the disease periodontal that live on the margin gingival (supragingival and under this (subgingival they have a direct relation that allows to support influential interactions in the growth and development of the different bacterial species that they live in the tissue periodontal.Therefore having removed the microorganisms that are located supragingivalmente would be possible to find changes in the way subgingival when an exchange not to exist between the aerobic environments (supragingival and anaerobic (subgingival once disorganized the bacterial plate supragingival. To demonstrate this relation 7 individuals selected with diagnosis of periodontitis chronicle moderate and severe to which they there was realized a destartraje supragingival of complete mouth to achieve supragingival to disorganize the bacterial plate. In turn microbiological samples of the sacks took periodontales deeper of every quadrant of these individuals, being the first taken sample before the destartraje supragingival considered as sample basal (the 0th, then they took at to 1, 7 and 21 days of removed the bacterial plate supragingival anaerobios (subgingival once disorganized the bacterial plate supragingival Of the results of the present study we could conclude that on having disorganized the biofilm supragingival a decrease is observed in the total quantity of microorganisms subgingivales, as well as also it diminishes in a considerable way the proportion of present Porphyoromona gingivalis in the way subgingival. Which would lead to thinking that there exists a direct and dependent relation between the microorganisms that live the way supragingival and subgingival.

  17. Prevalence of "non-oral" pathogenic bacteria in subgingival biofilm of subjects with chronic periodontitis Prevalência de bactérias patogênicas "não-orais" no biofilme dental subgengival de pacientes com periodontite crônica

    Directory of Open Access Journals (Sweden)

    Renata Souto

    2006-09-01

    Full Text Available The oral cavity may act as a reservoir for several pathogens related to systemic infections. Therefore, the purpose of this study was to determine the prevalence and levels of pathogenic bacteria in the subgingival biofilm of chronic periodontitis lesions and healthy periodontal sites using the checkerboard DNA-DNA hybridization technique. 200 samples of subgingival biofilm from sites with periodontitis (probing pocket depth > 4 mm and /or clinical attachment level > 4 mm and 200 samples from healthy sites of 14 patients with chronic periodontitis, as well as 200 samples from 3 periodontally healthy patients were obtained. The presence and levels of 11 pathogenic bacteria were determined using whole genomic DNA probes and the checkerboard method, computed for each site and then across sites within each subject group. Significance of differences in clinical and microbiological parameters among groups were examinated using the Mann-Whitney and Wilcoxon sign tests. The predominant species in all 600 samples included Corynebacterium diphtheriae, Enterococcus faecalis, Staphylococcus aureus,Acinetobacter baumannii and Escherichia coli. In general, most of the species were detected in greater prevalence and levels in sites with and without disease from patients with periodontitis in comparison to the periodontally healthy group. In particular, C. diphtheriae, E. coli, E. faecalis, P. aeruginosa and S. aureus were significantly more prevalent and detected in higher counts in diseased sites of patients with periodontal disease compared to healthy subjects (p Apesar da extensa literatura sobre a associação de bactérias orais e doenças sistêmicas, tem se dado pouca atenção à cavidade oral como um reservatório de bactérias patogênicas "não-orais". A microbiota oral é constituída de mais de 300 espécies bacterianas já caracterizadas, além de organismos não cultiváveis que vêm sendo descobertos através de técnicas moleculares. O

  18. Filifactor alocis--involvement in periodontal biofilms.

    Science.gov (United States)

    Schlafer, Sebastian; Riep, Birgit; Griffen, Ann L; Petrich, Annett; Hübner, Julia; Berning, Moritz; Friedmann, Anton; Göbel, Ulf B; Moter, Annette

    2010-03-01

    Bacteria in periodontal pockets develop complex sessile communities that attach to the tooth surface. These highly dynamic microfloral environments challenge both clinicians and researchers alike. The exploration of structural organisation and bacterial interactions within these biofilms is critically important for a thorough understanding of periodontal disease. In recent years, Filifactor alocis, a fastidious, Gram-positive, obligately anaerobic rod was repeatedly identified in periodontal lesions using DNA-based methods. It has been suggested to be a marker for periodontal deterioration. The present study investigated the epidemiology of F. alocis in periodontal pockets and analysed the spatial arrangement and architectural role of the organism in in vivo grown subgingival biofilms. A species-specific oligonucleotide probe, FIAL, was designed and evaluated. A total of 490 subgingival plaque samples were submitted to PCR and subsequent dot blot hybridization to compare the prevalence of F. alocis in patients suffering from generalized aggressive periodontitis (GAP), chronic periodontitis (CP), and control subjects resistant to periodontitis. Moreover, a specially designed carrier system was used to collect in vivo grown subgingival biofilms from GAP patients. Subsequent topographic analysis was performed using fluorescence in situ hybridization.While the majority of patients suffering from GAP or CP harboured F. alocis, it was rarely detected in the control group. In the examined carrier-borne biofilms the organism predominantly colonized apical parts of the pocket in close proximity to the soft tissues and was involved in numerous structures that constitute characteristic architectural features of subgingival periodontal biofilms. F. alocis is likely to make a relevant contribution to the pathogenetic structure of biofilms accounting for periodontal inflammation and can be considered an excellent marker organism for periodontal disease.

  19. Filifactor alocis - involvement in periodontal biofilms

    Directory of Open Access Journals (Sweden)

    Göbel Ulf B

    2010-03-01

    Full Text Available Abstract Background Bacteria in periodontal pockets develop complex sessile communities that attach to the tooth surface. These highly dynamic microfloral environments challenge both clinicians and researchers alike. The exploration of structural organisation and bacterial interactions within these biofilms is critically important for a thorough understanding of periodontal disease. In recent years, Filifactor alocis, a fastidious, Gram-positive, obligately anaerobic rod was repeatedly identified in periodontal lesions using DNA-based methods. It has been suggested to be a marker for periodontal deterioration. The present study investigated the epidemiology of F. alocis in periodontal pockets and analysed the spatial arrangement and architectural role of the organism in in vivo grown subgingival biofilms. Results A species-specific oligonucleotide probe, FIAL, was designed and evaluated. A total of 490 subgingival plaque samples were submitted to PCR and subsequent dot blot hybridization to compare the prevalence of F. alocis in patients suffering from generalized aggressive periodontitis (GAP, chronic periodontitis (CP, and control subjects resistant to periodontitis. Moreover, a specially designed carrier system was used to collect in vivo grown subgingival biofilms from GAP patients. Subsequent topographic analysis was performed using fluorescence in situ hybridization. While the majority of patients suffering from GAP or CP harboured F. alocis, it was rarely detected in the control group. In the examined carrier-borne biofilms the organism predominantly colonized apical parts of the pocket in close proximity to the soft tissues and was involved in numerous structures that constitute characteristic architectural features of subgingival periodontal biofilms. Conclusions F. alocis is likely to make a relevant contribution to the pathogenetic structure of biofilms accounting for periodontal inflammation and can be considered an excellent marker

  20. Bacterial diversity of biofilm samples from deep mines in South ...

    African Journals Online (AJOL)

    JTEkanem

    microbial diversity of mines in South Africa, biofilm samples were collected from Goldfield and diamond ... understand microbial biosynthetic processes and enhance remediation of contaminated environments3. The microbial diversity in these extreme environments has been the key to the ..... Biodiversity of acidophilic.

  1. [Using DGGE to analyze bacteria community structure changes in subgingival plaque after periodontal initial therapy].

    Science.gov (United States)

    Zhou, Yan-bin; Shu, Rong; Liu, Da-li

    2012-02-01

    To analyze bacteria community structure changes in subgingival plaque after initial therapy, and to provide experimental evidences for clinical decision. Six patients with chronic periodontitis were chosen. Subgingival plaque samples, as well as clinical indexes, were collected at baseline and six weeks after initial therapy. The generated two different 16S rDNA fragments of subgingival plaque samples were separated by denaturing gel, creating bands patterns representative of community structure. Subsequent cluster analysis was made. The clinical indexes were improved significantly. The diversity of population of clinical subgingival samples was not significantly different between baseline and 6 weeks after initial therapy. Through cluster analysis, it was confirmed that same patient got similar subgingival plaque between baseline and 6 weeks after treatment. Same patient tend to get similar subgingival plaque between baseline and after initial therapy. DGGE can detect the microbial composition of subgingival plaque.

  2. Phototrophic microorganisms in biofilm samples from Vernjika Cave, Serbia

    Science.gov (United States)

    Popović, Slađana; Jovanović, Jelena; Predojević, Dragana; Trbojević, Ivana; Blagojević, Ana; Subakov Simić, Gordana

    2016-04-01

    Caves represent specific natural monuments in terms of structure, complexity and beauty which can be found worldwide. Even though they are considered extreme environments, they are still a unique habitat for a large number of organisms that grow and proliferate here. Often can be seen that the cave walls are differently coloured as a consequence of the biofilm development. Biofilms represent complex communities of microorganisms that can develop on different kind of surfaces, including various rock surfaces. Each microbe species play a different role in a community, but their development on stone surfaces can cause substantial damage to the substrates through different mechanisms of biodeterioration and degradation. There is an increased interest in the phototrophic component of biofilms (aerophytic cyanobacteria and algae), especially cyanobacteria, an ancient microorganisms capable to survive the most diverse extreme conditions. These phototrophs can easily be found at cave entrances illuminated by direct or indirect sunlight and areas near artificial lights. Cyanobacteria and algae were investigated in biofilm samples taken from the entrance of Vernjika Cave in Eastern Serbia. Cyanobacteria, Chlorophyta and Bacillariophyta were documented, with Cyanobacteria as a group with the highest number of recorded taxa. Chroococcalean species were the most diverse with the most frequently encountered species from the genus Gloeocapsa. Phormidium and Nostoc species were commonly recorded Oscillatoriales and Nostocles, respectively. Among Oscillatoriales species, it was noticed that one Phormidium species precipitates CaCO3 on it's sheats. Trebouxia sp. and Desmococcus olivaceus were frequently documented Chlorophyta, and representatives of Bacillariophyta were exclusively aerophytic taxa, mostly belonging to the genera Luticola and Humidophila. Measured ecological parameters, temperature and relative humidity, were influenced by the external climatic changes, while light

  3. Activity of taurolidine gels on ex vivo periodontal biofilm.

    Science.gov (United States)

    Pirracchio, Luca; Joos, Aline; Luder, Nina; Sculean, Anton; Eick, Sigrun

    2017-12-14

    The purpose of this study is to evaluate the activity of two different taurolidine (TAU) gels in comparison with a 0.2% chlorhexidine (CHX) gel on an ex vivo subgingival biofilm. Subgingival including supragingival biofilm samples from periodontitis patients were cultured for 10 days, before TAU 1% and TAU 3% gels and CHX gel were applied for 10 min and thereafter diluted with nutrient media to 10% for 50 min. One third of the samples were analyzed for bacterial counts, biofilm quantity, and biofilm metabolic activity. In the two other thirds, 90% of the nutrient media were replaced and biofilms were incubated for 23 h. The second third was analyzed in the same way as before. In the third part, patients' microorganisms were added again and incubated for additional 24 h to allow reformation of biofilm before proceeding to analysis. Decrease of bacterial counts in biofilms was highest following application of TAU 3% after 60 min (0.87 log10 cfu, corresponding 86.5%), 24 and 48 h (reformation of biofilms), respectively. All antimicrobials reduced biofilm quantity after 24 h (each p activity in biofilms was decreased at 60 min (each p gels, while the activity of the reformed biofilm was lower after application of all evaluated antimicrobials (each p activity of taurolidine gels clearly depends on its taurolidine concentration. A high concentrated taurolidine gel is equally active or even superior to 0.2% chlorhexidine gel. However, the activity of antimicrobials is limited in a complex established biofilm and underlines the pivotal role of mechanical biofilm disruption. Within their limits, the data suggest that TAU 3% gel might represent a potential alternative to 0.2% chlorhexidine gel.

  4. Membrane biofouling characterization: effects of sample preparation procedures on biofilm structure and the microbial community

    KAUST Repository

    Xue, Zheng

    2014-07-15

    Ensuring the quality and reproducibility of results from biofilm structure and microbial community analysis is essential to membrane biofouling studies. This study evaluated the impacts of three sample preparation factors (ie number of buffer rinses, storage time at 4°C, and DNA extraction method) on the downstream analysis of nitrifying biofilms grown on ultrafiltration membranes. Both rinse and storage affected biofilm structure, as suggested by their strong correlation with total biovolume, biofilm thickness, roughness and the spatial distribution of EPS. Significant variations in DNA yields and microbial community diversity were also observed among samples treated by different rinses, storage and DNA extraction methods. For the tested biofilms, two rinses, no storage and DNA extraction with both mechanical and chemical cell lysis from attached biofilm were the optimal sample preparation procedures for obtaining accurate information about biofilm structure, EPS distribution and the microbial community. © 2014 © 2014 Taylor & Francis.

  5. The combined and individual impact of diabetes and smoking on key subgingival periodontal pathogens in patients with chronic periodontitis.

    Science.gov (United States)

    Joaquim, C R; Miranda, T S; Marins, L M; Silva, H D P; Feres, M; Figueiredo, L C; Duarte, P M

    2017-11-06

    Comprehension of the similarities and differences in the composition of the subgingival microbiota of patients with diabetes mellitus (DM), smokers or smokers with DM is an important step in developing therapies specific for these groups at risk for periodontitis. Therefore, the aim of this study was to compare the combined and individual effects of DM and smoking on the levels and prevalence of key subgingival periodontal pathogens in patients with chronic periodontitis. One hundred patients with generalized chronic periodontitis were allocated into one of the following groups: DM (n = 25, non-smokers with type 2 DM); S (n = 25, non-diabetic smokers); SDM (n = 25, smokers with type 2 DM); and control (n = 25, non-diabetic non-smokers). Two subgingival biofilm samples from healthy sites (probing depth and clinical attachment level ≤3 mm and no bleeding) and 2 from diseased sites (probing depth and clinical attachment level ≥5 mm and bleeding on probing) were analyzed by quantitative polymerase chain reaction for Porphyromonas gingivalis, Tannerella forsythia, Treponema denticola, Eubacterium nodatum, Parvimonas micra, Fusobacterium nucleatum ssp. and Prevotella intermedia. There were no differences among groups in the mean counts of the bacterial species studied, considering all sampled sites (healthy plus diseased sites). There were also no differences among groups regarding the prevalence of any bacteria species in healthy and diseased sites (P > .05). The mean P. micra count was significantly higher in the healthy sites of both smoking groups, than in those of the control group (P periodontitis presenting DM, smokers or smokers with DM. In addition, DM and smoking, jointly and individually, do not considerably affect the subgingival levels of target periodontal pathogens in patients with chronic periodontitis. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  6. The subgingival periodontal microbiota in the aging mouth

    Science.gov (United States)

    FERES, Magda; TELES, Flavia; TELES, Ricardo; FIGUEIREDO, Luciene Cristina; FAVERI, Marcelo

    2016-01-01

    Different mechanisms have been hypothesized to explain the increase in prevalence and severity of periodontitis in older adults, including shifts in the periodontal microbiota. However, the actual impact of aging in the composition of subgingival biofilms remains unclear. In the present article, we provide an overview of the composition of the subgingival biofilm in older adults and the potential effects of age on the oral microbiome. In particular, this review covers the following topics: (i) the oral microbiota of an aging mouth, (ii) the effects of age and time on the human oral microbiome, (iii) the potential impact of inflammaging and immunosenescence in the host-oral microbiota interactions, and (iv) the relationship of the aging oral microbiota and Alzheimer’s disease. Finally, in order to explore in greater breadth the potential effects of aging on the periodontal microbiota, we present analyses of data compiled from large clinical studies that evaluated the subgingival microbiota of periodontally healthy subjects and periodontitis patients from a wide age spectrum (20–83 years old). Those studies were conducted at Guarulhos University (São Paulo, SP, Brazil) and at The Forsyth Institute (Cambridge, USA), from 1999 to 2014. PMID:27501490

  7. The subgingival periodontal microbiota of the aging mouth.

    Science.gov (United States)

    Feres, Magda; Teles, Flavia; Teles, Ricardo; Figueiredo, Luciene Cristina; Faveri, Marcelo

    2016-10-01

    Different mechanisms have been hypothesized to explain the increase in prevalence and severity of periodontitis in older adults, including shifts in the periodontal microbiota. However, the actual impact of aging on the composition of subgingival biofilms remains unclear. In the present article, we provide an overview of the composition of the subgingival biofilm in older adults and the potential effects of age on the oral microbiome. In particular, this review covers the following topics: (i) the oral microbiota of an aging mouth; (ii) the effects of age and time on the human oral microbiome; (iii) the potential impact of inflammaging and immunosenescence in the host-oral microbiota interactions; and (iv) the relationship of the aging oral microbiota and Alzheimer's disease. Finally, we present analyses of data compiled from large clinical studies that evaluated the subgingival microbiota of periodontally healthy subjects and patients with periodontitis from a wide age spectrum (20-83 years of age). © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  8. Subgingival microbiota dysbiosis in systemic lupus erythematosus: association with periodontal status.

    Science.gov (United States)

    Corrêa, Jôice Dias; Calderaro, Débora Cerqueira; Ferreira, Gilda Aparecida; Mendonça, Santuza Maria Souza; Fernandes, Gabriel R; Xiao, E; Teixeira, Antônio Lúcio; Leys, Eugene J; Graves, Dana T; Silva, Tarcília Aparecida

    2017-03-20

    Periodontitis results from the interaction between a subgingival biofilm and host immune response. Changes in biofilm composition are thought to disrupt homeostasis between the host and subgingival bacteria resulting in periodontal damage. Chronic systemic inflammatory disorders have been shown to affect the subgingival microbiota and clinical periodontal status. However, this relationship has not been examined in subjects with systemic lupus erythematosus (SLE). The objective of our study was to investigate the influence of SLE on the subgingival microbiota and its connection with periodontal disease and SLE activity. We evaluated 52 patients with SLE compared to 52 subjects without SLE (control group). Subjects were classified as without periodontitis and with periodontitis. Oral microbiota composition was assessed by amplifying the V4 region of 16S rRNA gene from subgingival dental plaque DNA extracts. These amplicons were examined by Illumina MiSeq sequencing. SLE patients exhibited higher prevalence of periodontitis which occurred at a younger age compared to subjects of the control group. More severe forms of periodontitis were found in SLE subjects that had higher bacterial loads and decreased microbial diversity. Bacterial species frequently detected in periodontal disease were observed in higher proportions in SLE patients, even in periodontal healthy sites such as Fretibacterium, Prevotella nigrescens, and Selenomonas. Changes in the oral microbiota were linked to increased local inflammation, as demonstrated by higher concentrations of IL-6, IL-17, and IL-33 in SLE patients with periodontitis. SLE is associated with differences in the composition of the microbiota, independently of periodontal status.

  9. Antimicrobial effect of chlorhexidine on Aggregatibacter actinomycetemcomitans biofilms associated with peri-implantitis

    Science.gov (United States)

    Kadkhoda, Zeinab; Amarlu, Zeinab; Eshraghi, Saeed; Samiei, Nazanin

    2016-01-01

    Background. This study aimed to assessthe antimicrobial effect of chlorhexidine (CHX) on Aggregatibacter actinomycetemcomitans biofilms isolated from subgingival plaque of peri-implantitis lesions. Methods. Thirteen patients requiring peri-implantitis treatment were consecutively selected and their subgingival biofilm was collected by inserting fine sterile paper points into peri-implant pockets for 15 seconds. A. actinomycetemcomitans was isolated from the subgingival biofilm and cultured. In this study, the standard strain of A. actinomycetemcomitans served as the positive control group and a blank disc impregnated with water served as the negative control; 0.1 mL of the bacterial suspension was cultured on specific culture medium and blank discs (6 mm in diameter) impregnated with 0.2%CHX mouthrinse (Behsa Pharmaceutical Co.) and negative control discs were placed on two sides of the bacterial culture plate. The size of growth inhibition zone was measured by a blinded independent observer in millimetres. Results. According to the results of disc diffusion test, the mean diameter of growth inhibition zone of A. actinomycetemcomitans around discs impregnated with CHX was larger in both standard (positive control) and biofilm samples of A. actinomycetemcomitans compared to the negative control group (blank disc) (Pimplantitis sites. PMID:27651884

  10. Antimicrobial effect of chlorhexidine on Aggregatibacter actinomycetemcomitans biofilms associated with peri-implantitis

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    Zeinab Kadkhoda

    2016-08-01

    Full Text Available Background. This study aimed to assessthe antimicrobial effect of chlorhexidine (CHX on Aggregatibacter actinomyce-temcomitans biofilms isolated from subgingival plaque of peri-implantitis lesions. Methods. Thirteen patients requiring peri-implantitis treatment were consecutively selected and their subgingival biofilm was collected by inserting fine sterile paper points into peri-implant pockets for 15 seconds. A. actinomycetemcomitans was isolated from the subgingival biofilm and cultured. In this study, the standard strain of A. actinomycetemcomitans served as the positive control group and a blank disc impregnated with water served as the negative control; 0.1 mL of the bacterial suspension was cultured on specific culture medium and blank discs (6 mm in diameter impregnated with 0.2%CHX mouthrinse (Behsa Pharmaceutical Co. and negative control discs were placed on two sides of the bacterial culture plate. The size of growth inhibition zone was measured by a blinded independent observer in millimetres. Results. According to the results of disc diffusion test, the mean diameter of growth inhibition zone of A. actinomycetem-comitans around discs impregnated with CHX was larger in both standard (positive control and biofilm samples of A. acti-nomycetemcomitans compared to the negative control group (blank disc (P<0.001. Conclusion. Use of0.2% CHX mouthwash had antibacterial effects on A. actinomycetemcomitans species isolated from peri-implantitis sites.

  11. Microbial shifts during dental biofilm re-development in the absence of oral hygiene in periodontal health and disease.

    Science.gov (United States)

    Uzel, Naciye G; Teles, Flavia R; Teles, Ricardo P; Song, Xiaoging Q; Torresyap, Gay; Socransky, Sigmund S; Haffajee, Anne D

    2011-07-01

    To monitor microbial shifts during dental biofilm re-development. Supra- and subgingival plaque samples were taken separately from 28 teeth in 38 healthy and 17 periodontitis subjects at baseline and immediately after tooth cleaning. Samples were taken again from seven teeth in randomly selected quadrants during 1, 2, 4 and 7 days of no oral hygiene. Samples were analysed using checkerboard DNA-DNA hybridization. Species counts were averaged within subjects at each time point. Significant differences in the counts between healthy and periodontitis subjects were determined using the Mann-Whitney test. The total supra- and subgingival counts were significantly higher in periodontitis on entry and reached or exceeded the baseline values after day 2. Supragingival counts of Veillonella parvula, Fusobacterium nucleatum ss vincentii and Neisseria mucosa increased from 2 to 7 days. Subgingival counts were greater for Actinomyces, green and orange complex species. Significant differences between groups in supragingival counts occurred for 17 of 41 species at entry, 0 at day 7; for subgingival plaque, these values were 39/41 taxa at entry, 17/41 at day 7. Supragingival plaque re-development was similar in periodontitis and health, but subgingival species recolonization was more marked in periodontitis. © 2011 John Wiley & Sons A/S.

  12. PCR detection of four periodontopathogens from subgingival clinical samples Detecção por PCR de quatro periodontopatógenos de pacientes com doença periodontal e de indivíduos sadios

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    Mario Julio Avila-Campos

    2003-04-01

    Full Text Available In this study, A. actinomycetemcomitans, B. forsythus, P. gingivalis and F. nucleatum were identified from subgingival plaque from 50 periodontal patients and 50 healthy subjects. Subgingival clinical samples were collected with sterilized paper points and transported in VMGA III. From all the diluted clinical samples (1:10, DNA was obtained by boiling, and after centrifugation the supernatant was used as template. Specific primers for each bacterial species were used in PCR. PCR amplification was sensitive to identify these organisms. PCR products from each species showed a single band and can be used to identify periodontal organisms from clinical specimens. PCR detection odds ratio values for A. actinomycetemcomitans and B. forsythus were significantly associated with disease showing a higher OR values for B. forsythus (2.97, 95% CI 1.88 - 4.70. These results suggest a strong association among the studied species and the periodontal lesion.Em nosso estudo quatro periodontopatógenos foram isolados e identificados de placas subgengivais de 50 pacientes com doença periodontal e de 50 indivíduos sadios. As placas subgengivais foram coletadas com pontas de papel e transportadas em VMGA III. Foram realizadas diluições seriadas das amostras clínicas (1:10, e os DNA foram obtidos por fervura. Iniciadores específicos para cada bactéria foram usados no PCR. As amplificações mostraram-se sensíveis na identificação de A. actinomycetemcomitans, B. forsythus, P. gingivalis e F. nucleatum. As reações de PCR produziram bandas específicas para cada espécie e podem ser usadas na identificação desses organismos periodontais diretamente das amostras clínicas. Os valores de odds ratio para a detecção de A. actinomycetemcomitans e B. forsythus foram significativamente associados com a doença periodontal mostrando altos valores de OR para B. forsythus (2,97, 95% CI 1,88 - 4,70. Esses resultados sugerem uma forte associação entre os

  13. Comparison of RNA extraction methods from biofilm samples of Staphylococcus epidermidis

    Directory of Open Access Journals (Sweden)

    França Angela

    2011-12-01

    Full Text Available Abstract Background Microbial biofilms are communities of bacteria adhered to a surface and surrounded by an extracellular polymeric matrix. Biofilms have been associated with increased antibiotic resistance and tolerance to the immune system. Staphylococcus epidermidis is the major bacterial species found in biofilm-related infections on indwelling medical devices. Obtaining high quality mRNA from biofilms is crucial to validate the transcriptional measurements associated with the switching to the biofilm mode of growth. Therefore, we selected three commercially available RNA extraction kits with distinct characteristics, including those using silica membrane or organic extraction methods, and enzymatic or mechanical cell lysis, and evaluated the RNA quality obtained from two distinct S. epidermidis bacterial biofilms. Results RNA extracted using the different kits was evaluated for quantity, purity, integrity, and functionally. All kits were able to extract intact and functional total RNA from the biofilms generated from each S. epidermidis strain. The results demonstrated that the kit based on mechanical lysis and organic extraction (FastRNA® Pro Blue was the only one that was able to isolate pure and large quantities of RNA. Normalized expression of the icaA virulence gene showed that RNA extracted with PureLink™ had a significant lower concentration of icaA mRNA transcripts than the other kits tested. Conclusions When working with complex samples, such as biofilms, that contain a high content extracellular polysaccharide and proteins, special care should be taken when selecting the appropriate RNA extraction system, in order to obtain accurate, reproducible, and biologically significant results. Among the RNA extraction kits tested, FastRNA® Pro Blue was the best option for both S. epidermidis biofilms used.

  14. Comparative evaluation of two subgingival irrigating solutions in the management of periodontal disease: A clinicomicrobial study

    Directory of Open Access Journals (Sweden)

    Dhara Jayesh Pandya

    2016-01-01

    Full Text Available Context: Local administration of antimicrobial agents offer a “site-specific” approach to the periodontal therapy and it has several benefits. Aim: The present study was aimed to assess the clinical and microbial changes by subgingival irrigation using different subgingival irrigants in periodontitis patients and also to assess the mechanical effect of different local irrigation devices; if any. Settings and Design: Split-mouth design was employed on ten individuals. Materials and Methods: The study sample consisted of 10 individuals in whom full-mouth scaling and root planing was performed and subgingival irrigation therapy was instituted for an experimental period of 30 days. The clinical as well as microbiological parameters were evaluated. Statistical Analysis Used: To calculate baseline data with day thirty data,paired t-test was used. Intergroup comparison was carried out using one-way ANOVA. Multiple comparisons among groups were carried out using post hoc Tamhane's T2 test. Results: Among the different subgingival irrigants used, 0.2% chlorhexidine gluconate is most effective followed by ozonated water, whereas saline was found to be ineffective when compared to the other two subgingival irrigants. Subgingival irrigation using pulsated device may not have any additive effect in alteration of the subgingival microflora. Conclusion: Within the limits and scope of the study, it can be safely concluded that 0.2% chlorhexidine may be used as an adjunct to mechanical therapy for achieving a significant reduction in inflammatory periodontal changes and also reduction in periodontopathogenic microflora.

  15. Sampling natural biofilms: a new route to build efficient microbial anodes.

    Science.gov (United States)

    Erable, Benjamin; Roncato, Marie-Anne; Achouak, Wafa; Bergel, Alain

    2009-05-01

    Electrochemically active biofilms were constructed on graphite anodes under constant polarization at -0.1V vs saturated calomel reference (SCE) with 10 mM acetate as substrate. The reactors were inoculated with three different microbial samples that were drawn from exactly the same place in a French Atlantic coastal port (i) by scraping the biofilm that had formed naturally on the surface of a floating bridge, (ii) by taking marine sediments just under the floating bridge, and (iii) by taking nearby beach sand. Current densities of 2.0 A/m2 were reached using the biofilm sample as inoculum while only 0.4 A/m2 and 0.8 A/m2 were obtained using the underlying sediments and the beach sand, respectively. The structure of bacterial communities forming biofilms was characterized by denaturing gradient gel electrophoresis (DGGE) analysis, and revealed differences between samples with the increase in relative intensities of some bands and the appearance of others. Bacteria close related to Bacteroidetes, Halomonas, and Marinobacterium were retrieved only from the efficient EA-biofilms formed from natural biofilms, whereas, bacteria close related to Mesoflavibacter were predominant on biofilm formed from sediments. The marine biofilm was selected as the inoculum to further optimize the microbial anode. Epifluorescence microscopy and SEM confirmed that maintaining the electrode under constant polarization promoted rapid settlement of the electrode surface by a bacterial monolayer film. The microbial anode was progressively adapted to the consumption of acetate by three serial additions of substrate, thus improving the Coulombic efficiency of acetate consumption from 31 to 89%. The possible oxidation of sulfide played only a very small part in the current production and the biofilm was not able to oxidize hydrogen. Graphite proved to be more efficient than dimensionally stable anode (DSA) or stainless steel butthis result might be due to differences in the surface roughness

  16. Rapid detection of Naegleria fowleri in water distribution pipeline biofilms and drinking water samples.

    Science.gov (United States)

    Puzon, Geoffrey J; Lancaster, James A; Wylie, Jason T; Plumb, Iason J

    2009-09-01

    Rapid detection of pathogenic Naegleria fowler in water distribution networks is critical for water utilities. Current detection methods rely on sampling drinking water followed by culturing and molecular identification of purified strains. This culture-based method takes an extended amount of time (days), detects both nonpathogenic and pathogenic species, and does not account for N. fowleri cells associated with pipe wall biofilms. In this study, a total DNA extraction technique coupled with a real-time PCR method using primers specific for N. fowleri was developed and validated. The method readily detected N. fowleri without preculturing with the lowest detection limit for N. fowleri cells spiked in biofilm being one cell (66% detection rate) and five cells (100% detection rate). For drinking water, the detection limit was five cells (66% detection rate) and 10 cells (100% detection rate). By comparison, culture-based methods were less sensitive for detection of cells spiked into both biofilm (66% detection for pipe wall biofilm samples obtained from a distribution network enabled the detection of N. fowleri in under 6 h, versus 3+ daysforthe culture based method. Further, comparison of the real-time PCR data from the field samples and the standard curves enabled an approximation of N. fowleri cells in the biofilm and drinking water. The use of such a method will further aid water utilities in detecting and managing the persistence of N. fowleri in water distribution networks.

  17. Endoscopic vs. tactile evaluation of subgingival calculus.

    Science.gov (United States)

    Osborn, Joy B; Lenton, Patricia A; Lunos, Scott A; Blue, Christine M

    2014-08-01

    Endoscopic technology has been developed to facilitate imagery for use during diagnostic and therapeutic phases of periodontal care. The purpose of this study was to compare the level of subgingival calculus detection using a periodontal endoscope with that of conventional tactile explorer in periodontitis subjects. A convenience sample of 26 subjects with moderate periodontitis in at least 2 quadrants was recruited from the University of Minnesota School of Dentistry to undergo quadrant scaling and root planing. One quadrant from each subject was randomized for tactile calculus detection alone and the other quadrant for tactile detection plus the Perioscope ™ (Perioscopy Inc., Oakland, Cali). A calculus index on a 0 to 3 score was performed at baseline and at 2 post-scaling and root planing visits. Sites where calculus was detected at visit 1 were retreated. T-tests were used to determine within-subject differences between Perioscope™ and tactile measures, and changes in measures between visits. Significantly more calculus was detected using the Perioscope™ vs. tactile explorer for all 3 subject visits (pcalculus detection from baseline to visit 1 were statistically significant for both the Perioscope™ and tactile quadrants (pcalculus detection from visit 1 to visit 2 was only significant for the Perioscope™ quadrant (pcalculus at this visit. It was concluded that the addition of a visual component to calculus detection via the Perioscope™ was most helpful in the re-evaluation phase of periodontal therapy. Copyright © 2014 The American Dental Hygienists’ Association.

  18. Initial effect of controlled release chlorhexidine on subgingival microorganisms.

    Science.gov (United States)

    Daneshmand, Nazanin; Jorgensen, Michael G; Nowzari, Hessam; Morrison, John L; Slots, Jørgen

    2002-10-01

    Little or no data exist on the ability of subgingival application of PerioChip (2.5 mg chlorhexidine gluconate in a biodegradable chip; Astra Pharmaceuticals, Westborough, MA, USA) to suppress periodontopathic microorganisms. The present study compared the subgingival microbiota of periodontitis sites receiving the chlorhexidine chip plus scaling and root planing (Sc/Rp) or Sc/Rp alone. Seven males and six females, mean age 49 years, with moderate to advanced periodontitis participated in the study. In each patient, two bilateral pockets probing 6-7 mm were randomly assigned to treatment by chlorhexidine chip + Sc/Rp, or by Sc/Rp alone. Subgingival placement of chlorhexidine chips was carried out according to the manufacturer's instructions. Sc/Rp was performed with hand instruments for at least 10 min in each study tooth. Subgingival samples were collected by paper-points at baseline, at 2 weeks and at 4 weeks post-treatment. Anaerobic culture methods were used for microbial isolation and identification. The microbiologic examination was carried out blindly. Microbiological data were evaluated by a repeated measures analysis of variance. No statistical difference was found in total colony counts between subgingival sites treated with chlorhexidine chip + Sc/Rp and those treated with Sc/Rp alone. Also, the percentage of major periodontal pathogens (Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis and Bacteroides forsythus) and the percentage of total periodontal pathogens (A. actinomycetemcomitans, P. gingivalis, B. forsythus, Prevotella intermedia-group, Fusobacterium, Eubacterium, Campylobacter rectus, Peptostreptococcus micros, Eikenella corrodens, enteric rods) were not significantly different between the chlorhexidine chip + Sc/Rp group and the Sc/Rp group. At baseline, A. actinomycetemcomitans was recovered from 4 chlorhexidine chip + Sc/Rp sites and 2 Sc/Rp sites, P. gingivalis from 5 chlorhexidine chip + Sc/Rp sites and 4 Sc/Rp sites, and B

  19. Utilization of substrates by bacterial communities (biofilm) as they develop on stored chicken meat samples.

    Science.gov (United States)

    Boothe, D D; Arnold, J W; Chew, V

    1999-12-01

    Understanding and controlling the metabolic processes of microorganisms associated with chicken meat can lead to safer poultry products with a longer shelf life. The objective of the present study was threefold: 1) to determine the feasibility of using 96-well Biolog GN microtiter plates to assess substrate utilization profiles of bacterial communities (biofilm) as they develop on poultry products, 2) to identify substrates metabolized by microbial populations associated with stored chicken meat, and 3) to compare the substrate utilization profiles of biofilm communities as they develop on meat stored at 4 C (refrigeration temperature) for up to 5 d or at 13 C (a temperature common in poultry processing areas) for 2 d. The protocol used herein for preparing inocula for microplates was acceptable for the collection of optical density values (590 nm) in microplate wells as an indicator of microbial substrate utilization over time. Data from treatment of chicken meat samples using this protocol indicate that most of the 95 substrates tested were metabolized by microbial communities present as early as 1 d after storage at 4 or at 13 C. However, the rapidity (incubation time required for initial substrate utilization) and frequency (percentage of plates positive for transformation of an individual substrate) of metabolism of the substrates by the biofilm communities varied from 4 to 164 h of plate incubation and from 17 to 100% of microplates, respectively. At 13 C, polymers were the most rapidly metabolized substrate group, followed by carbohydrates, carboxylic acids, miscellaneous or amino acids, and amides or amines. Initial utilization of these substrate groups at 4 C occurred within a consistently shorter period (24 h of plate incubation). The frequency of metabolism of each individual substrate group varied only 3 to 16% between samples stored at 4 and 13 C. However, a greater difference in frequency of utilization of some individual substrates was noted. Such

  20. [Evaluation of clinical efficacy of casting pure titanium ring on reparation of subgingival residual root].

    Science.gov (United States)

    Huang, Lei; Wang, Peng

    2013-10-01

    To explore treatment regime and curative effect of the casting pure titanium ring on reparation of subgingival residual root. Thirty-two teeth were selected for reparation of subgingival residual root after root canal therapy in our department during 2008-2010. The teeth were restored with casting pure titanium ring, glass fiber post and all-ceramic crown. The patients were recalled 12 and 24 months after placement of the pure titanium ring. Gingival crevicular fluid(GCF) samples were collected by filter paper strips. Then the weight of GCF was detected and the gingival index was recorded. The data was analyzed for paired samples t test by SPSS17.0 software package. There was no significant difference in the weight of GCF and the gingival index before and after placement of pure titanium ring (P<0.05). By using pure titanium ring, most subgingival residual root after root canal therapy can be rehabilitated and function well for long time.

  1. Subgingival bacterial colonization profiles correlate with gingival tissue gene expression

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    Handfield Martin

    2009-10-01

    Full Text Available Abstract Background Periodontitis is a chronic inflammatory disease caused by the microbiota of the periodontal pocket. We investigated the association between subgingival bacterial profiles and gene expression patterns in gingival tissues of patients with periodontitis. A total of 120 patients undergoing periodontal surgery contributed with a minimum of two interproximal gingival papillae (range 2-4 from a maxillary posterior region. Prior to tissue harvesting, subgingival plaque samples were collected from the mesial and distal aspects of each tissue sample. Gingival tissue RNA was extracted, reverse-transcribed, labeled, and hybridized with whole-genome microarrays (310 in total. Plaque samples were analyzed using checkerboard DNA-DNA hybridizations with respect to 11 bacterial species. Random effects linear regression models considered bacterial levels as exposure and expression profiles as outcome variables. Gene Ontology analyses summarized the expression patterns into biologically relevant categories. Results Wide inter-species variation was noted in the number of differentially expressed gingival tissue genes according to subgingival bacterial levels: Using a Bonferroni correction (p -7, 9,392 probe sets were differentially associated with levels of Tannerella forsythia, 8,537 with Porphyromonas gingivalis, 6,460 with Aggregatibacter actinomycetemcomitans, 506 with Eikenella corrodens and only 8 with Actinomyces naeslundii. Cluster analysis identified commonalities and differences among tissue gene expression patterns differentially regulated according to bacterial levels. Conclusion Our findings suggest that the microbial content of the periodontal pocket is a determinant of gene expression in the gingival tissues and provide new insights into the differential ability of periodontal species to elicit a local host response.

  2. Occurrence of yeasts, enterococci and other enteric bacteria in subgingival biofilm of HIV-positive patients with chronic gingivitis and necrotizing periodontitis Ocorrência de leveduras, enterococos e outras bactérias entéricas no biofilme subgengival de pacientes HIV-positivos com gengivite crônica e periodontite necrosante

    Directory of Open Access Journals (Sweden)

    Elerson Gaetti-Jardim Júnior

    2008-06-01

    Full Text Available The purpose of this study was to determine the prevalence of enteric bacteria and yeasts in biofilm of 80 HIV-positive patients with plaque-associated gingivitis or necrotizing periodontitis. Patients were subjected to extra, intra oral and radiographic examinations. The oral hygiene, bleeding on probing, gingival conditions, and attachment loss were evaluated. Clinical specimens were collected from gingival crevices or periodontal pockets, transferred to VMGA III, diluted and transferred to Sabouraud Dextrose agar with 100 µg/ml of chloramphenicol, peptone water, EVA broth, EMB agar, SS agar, Bile esculin agar and Brilliant green agar. Isolation of yeasts was carried out at room temperature, for 3-7 days; and for the isolation of enteric microorganisms plates were incubated at 37ºC, for 24-48 h. The yeasts identification was performed according to the carbon and nitrogen assimilation, fermentation of carbohydrates and germ tube formation. Bacteria were identified according to their colonial and cellular morphologies and biochemical tests. Yeasts were identified as Candida albicans and its occurrence was more common in patients with CD4+ below 200/mm³ and was affected by the extension of periodontal involvement (P = 0.0345. Enteric bacteria recovered from clinical specimens were identified as Enterobacter sakazakii, Enterobacter cloacae, Serratia liquefaciens, Klebsiella oxytoca and Enterococcus sp. Enterobacteriaceae and enterococci were detected in 32.5% of clinical samples from patients with necrotizing periodontitis. In conclusion, non-oral pathogenic bacteria and C. albicans were more prevalent in periodontal sites of HIV-positive patients with necrotizing periodontitis and chronic gingivitis.O objetivo desse estudo foi avaliar a ocorrência de bactérias entéricas e leveduras no biofilme subgengival de pacientes HIV-positivos com gengivite crônica ou periodontite necrosante. Os pacientes foram submetidos a exame clínico e radiogr

  3. Smoking affects the subgingival microflora in periodontitis

    NARCIS (Netherlands)

    van Winkelhoff, AJ; Bosch-Tijhof, CJ; Winkel, EG; van der Reijden, WA

    Background: Tobacco smoking has been identified as one major risk factor for destructive periodontal disease. Scaling and root planing have been shown to be less effective in smokers with periodontitis. The aim of the present study was to compare the subgingival microbial flora of treated and

  4. Subgingival Human Cytomegalovirus and Epstein Barr Virus in Patients with Aggressive Periodontitis in Ahwaz, Iran

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    M. Jahangirnezhad

    2009-06-01

    Full Text Available Objective: Assessment of subgingival human cytomegalovirus (HCMV and Epstein Barr virus (EBV-1 in subjects with aggressive periodontitis.Materials and Methods: Samples were obtained from plaques formed in subgingival regions of 26 aggressive periodontitis patients. All specimens were submitted to polymerase chain reaction in order to detect HCMV and EBV-1.Results: HCMV and EBV-1 were observed in 27% and 25% of the participants respectively.Coinfection with both viruses was found in 52% of the patients.Conclusion: Within the limitations of the present study, it can be suggested that HCMV and EBV-1 in subgingival plaques may be associated with aggressive periodontitis. Additionally,concomitant occurrence of these viruses may negatively affect the wellbeing ofperiodontal tissues.

  5. Evaluation of Two Surface Sampling Methods for Microbiological and Chemical Analyses To Assess the Presence of Biofilms in Food Companies.

    Science.gov (United States)

    Maes, Sharon; Huu, Son Nguyen; Heyndrickx, Marc; Weyenberg, Stephanie van; Steenackers, Hans; Verplaetse, Alex; Vackier, Thijs; Sampers, Imca; Raes, Katleen; Reu, Koen De

    2017-12-01

    Biofilms are an important source of contamination in food companies, yet the composition of biofilms in practice is still mostly unknown. The chemical and microbiological characterization of surface samples taken after cleaning and disinfection is very important to distinguish free-living bacteria from the attached bacteria in biofilms. In this study, sampling methods that are potentially useful for both chemical and microbiological analyses of surface samples were evaluated. In the manufacturing facilities of eight Belgian food companies, surfaces were sampled after cleaning and disinfection using two sampling methods: the scraper-flocked swab method and the sponge stick method. Microbiological and chemical analyses were performed on these samples to evaluate the suitability of the sampling methods for the quantification of extracellular polymeric substance components and microorganisms originating from biofilms in these facilities. The scraper-flocked swab method was most suitable for chemical analyses of the samples because the material in these swabs did not interfere with determination of the chemical components. For microbiological enumerations, the sponge stick method was slightly but not significantly more effective than the scraper-flocked swab method. In all but one of the facilities, at least 20% of the sampled surfaces had more than 102 CFU/100 cm2. Proteins were found in 20% of the chemically analyzed surface samples, and carbohydrates and uronic acids were found in 15 and 8% of the samples, respectively. When chemical and microbiological results were combined, 17% of the sampled surfaces were contaminated with both microorganisms and at least one of the analyzed chemical components; thus, these surfaces were characterized as carrying biofilm. Overall, microbiological contamination in the food industry is highly variable by food sector and even within a facility at various sampling points and sampling times.

  6. Reducing allergic symptoms through eliminating subgingival plaque

    Directory of Open Access Journals (Sweden)

    Haryono Utomo

    2008-12-01

    Full Text Available Background: Elimination of subgingival plaque for prevention and treatment of periodontal diseases through scaling is a routine procedure. It is also well-known that periodontal disease is related to systemic diseases. Nevertheless, the idea how scaling procedures also able to reduce allergic symptoms i.e. eczema and asthma, is not easily accepted, because it is contradictory to the “hygiene hypothesis”. However, since allergic symptoms also depend on variable factors such as genetic, environmental and infection factors; every possible effort to eliminate or avoid from these factors had to be considered. Subgingival plaque is a source of infection, especially the Gram-negative bacteria that produced endotoxin (lipopolysaccharides, LPS, a potential stimulator of immunocompetent cells, which may also related to allergy, such as mast cells and basophils. In addition, it also triggers the “neurogenic switching” mechanism which may be initiated from chronic gingivitis. Objective: This case report may explain the possible connection between subgingival plaque and allergy based on evidence-based cases. Case: Two adult siblings who suffered from chronic gingivitis also showed different manifestations of allergy that were allergic dermatitis and asthma for years. They were also undergone unsuccessful medical treatment for years. Oral and topical corticosteroids were taken for dermatitis and inhalation for asthma. Case Management: Patients were conducted deep scaling procedures, allergic symptoms gradually diminished in days even though without usual medications. Conclusion: Concerning to the effectiveness of scaling procedures which concomitantly eliminate subgingival plaque in allergic patients, it concluded that this concept is logical. Nevertheless, further verification and collaborated study with allergic expert should be done.

  7. Reducing allergic symptoms through eliminating subgingival plaque

    OpenAIRE

    Utomo, Haryono; Prahasanti, Chiquita; Ruhadi, Iwan

    2008-01-01

    Background: Elimination of subgingival plaque for prevention and treatment of periodontal diseases through scaling is a routine procedure. It is also well-known that periodontal disease is related to systemic diseases. Nevertheless, the idea how scaling procedures also able to reduce allergic symptoms i.e. eczema and asthma, is not easily accepted, because it is contradictory to the “hygiene hypothesis”. However, since allergic symptoms also depend on variable factors such as genetic, environ...

  8. Characteristics of subgingival calculus detection by multiphoton fluorescence microscopy

    Science.gov (United States)

    Tung, Oi-Hong; Lee, Shyh-Yuan; Lai, Yu-Lin; Chen, How-Foo

    2011-06-01

    Subgingival calculus has been recognized as a major cause of periodontitis, which is one of the main chronic infectious diseases of oral cavities and a principal cause of tooth loss in humans. Bacteria deposited in subgingival calculus or plaque cause gingival inflammation, function deterioration, and then periodontitis. However, subgingival calculus within the periodontal pocket is a complicated and potentially delicate structure to be detected with current dental armamentaria, namely dental x-rays and dental probes. Consequently, complete removal of subgingival calculus remains a challenge to periodontal therapies. In this study, the detection of subgingival calculus employing a multiphoton autofluorescence imaging method was characterized in comparison with a one-photon confocal fluorescence imaging technique. Feasibility of such a system was studied based on fluorescence response of gingiva, healthy teeth, and calculus with and without gingiva covered. The multiphoton fluorescence technology perceived the tissue-covered subgingival calculus that cannot be observed by the one-photon confocal fluorescence method.

  9. Comparative evaluation of subgingival plaque microflora in pregnant and non-pregnant women: A clinical and microbiologic study

    Directory of Open Access Journals (Sweden)

    Rishi Emmatty

    2013-01-01

    Full Text Available Context: Gingival changes in pregnancy have been attributed to changes in the subgingival biofilm related to hormonal variations. Aims: To evaluate the subgingival plaque microflora in pregnant and nonpregnant women to determine if pregnancy induces any alterations in the subgingival plaque and to associate these changes with changes in periodontal status. Settings and Design: Thirty pregnant and 10 nonpregnant women within the age group of 20-35 years having a probing pocket depth (PPD of 3-4 mm were included in the study. The pregnant women were equally divided into 3 groups of 10, each belonging to I, II, and III trimester. Materials and Methods: Plaque index, gingival index, PPD, and microbiologic evaluation for specific bacterial counts for Prevotella intermedia, Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans, Parvimonas micra, and Fusobacterium nucleatum were carried out for all subjects. Statistical Analysis: Mann-Whitney U test. Results: Increase in gingival inflammation was observed in II and III trimester as compared with I trimester and control. Plaque scores did not show any significant difference between pregnant and nonpregnant women. Specific bacterial examination revealed an increase in proportion of P. intermedia in pregnant women of both II and III trimester as compared with I trimester and nonpregnant women. Conclusions: A definite increase in proportions of P. intermedia occurs in subgingival plaque microflora in pregnancy that may be responsible for the exaggerated gingival response.

  10. Detection of Escherichia coli in biofilms from pipe samples and coupons in drinking water distribution networks.

    Science.gov (United States)

    Juhna, T; Birzniece, D; Larsson, S; Zulenkovs, D; Sharipo, A; Azevedo, N F; Ménard-Szczebara, F; Castagnet, S; Féliers, C; Keevil, C W

    2007-11-01

    Fluorescence in situ hybridization (FISH) was used for direct detection of Escherichia coli on pipe surfaces and coupons in drinking water distribution networks. Old cast iron main pipes were removed from water distribution networks in France, England, Portugal, and Latvia, and E. coli was analyzed in the biofilm. In addition, 44 flat coupons made of cast iron, polyvinyl chloride, or stainless steel were placed into and continuously exposed to water on 15 locations of 6 distribution networks in France and Latvia and examined after 1 to 6 months exposure to the drinking water. In order to increase the signal intensity, a peptide nucleic acid (PNA) 15-mer probe was used in the FISH screening for the presence or absence of E. coli on the surface of pipes and coupons, thus reducing occasional problems of autofluorescence and low fluorescence of the labeled bacteria. For comparison, cells were removed from the surfaces and examined with culture-based or enzymatic (detection of beta-d-glucuronidase) methods. An additional verification was made by using PCR. Culture method indicated presence of E. coli in one of five pipes, whereas all pipes were positive with the FISH methods. E. coli was detected in 56% of the coupons using PNA FISH, but no E. coli was detected using culture or enzymatic methods. PCR analyses confirmed the presence of E. coli in samples that were negative according to culture-based and enzymatic methods. The viability of E. coli cells in the samples was demonstrated by the cell elongation after resuscitation in low-nutrient medium supplemented with pipemidic acid, suggesting that the cells were present in an active but nonculturable state, unable to grow on agar media. E. coli contributed to ca. 0.001 to 0.1% of the total bacterial number in the samples. The presence and number of E. coli did not correlate with any of physical and/or chemical characteristic of the drinking water (e.g., temperature, chlorine, or biodegradable organic matter concentration

  11. Limitations of Using Propidium Monoazide with qPCR to Discriminate between Live and Dead in Biofilm Samples

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    Michael J. Taylor

    2014-01-01

    Full Text Available Accurately quantifying Legionella for regulatory purposes to protect public health is essential. Real-time PCR (qPCR has been proposed as a better method for detecting and enumerating Legionella in samples than conventional culture method. However, since qPCR amplifies any target DNA in the sample, the technique's inability to discriminate between live and dead cells means that counts are generally significantly overestimated. Propidium monoazide (PMA has been used successfully in qPCR to aid live/dead discrimination. We tested PMA use as a method to count only live Legionella cells in samples collected from a modified chemostat that generates environmentally comparable samples. Counts from PMA-treated samples that were pretreated with either heat or three types of disinfectants (to kill the cells were highly variable, with the only consistent trend being the relationship between biofilm mass and numbers of Legionella cells. Two possibilities explain this result: 1. PMA treatment worked and the subsequent muted response of Legionella to disinfection treatment is a factor of biofilm/microbiological effects; although this does not account for the relationship between the amount of biofilm sampled and the viable Legionella count as determined by PMA-qPCR; or 2. PMA treatment did not work, and any measured decrease or increase in detectable Legionella is because of other factors affecting the method. This is the most likely explanation for our results, suggesting that higher concentrations of PMA might be needed to compensate for the presence of other compounds in an environmental sample or that lower amounts of biofilm need to be sampled. As PMA becomes increasingly toxic at higher concentrations and is very expensive, augmenting the method to include higher PMA concentrations is both counterproductive and cost prohibitive. Conversely, if smaller volumes of biofilm are used, the reproducibility of the method is reduced. Our results suggest that

  12. Subgingival debridement of periodontal pockets by air polishing in comparison with ultrasonic instrumentation during maintenance therapy.

    Science.gov (United States)

    Wennström, Jan L; Dahlén, Gunnar; Ramberg, Per

    2011-09-01

    The objective was to determine clinical and microbiological effects and perceived treatment discomfort of root debridement by subgingival air polishing compared with ultrasonic instrumentation during supportive periodontal therapy (SPT). The trial was conducted as a split-mouth designed study of 2-month duration including 20 recall patients previously treated for chronic periodontitis. Sites with probing pocket depth (PPD) of 5-8 mm and bleeding on probing (BoP+) in two quadrants were randomly assigned to subgingival debridement by (i) glycine powder/air polishing applied with a specially designed nozzle or (ii) ultrasonic instrumentation. Clinical variables were recorded at baseline, 14 and 60 days post-treatment. Primary clinical efficacy variable was PPD reduction. Microbiological analysis of subgingival samples was performed immediately before and after debridement, 2 and 14 days post-treatment. Both treatment procedures resulted in significant reductions of periodontitis-associated bacterial species immediately and 2 days after treatment, and in significant reduction in BoP, PPD and relative attachment level at 2 months. There were no statistically significant differences between the treatment procedures at any of the examinations intervals. Perceived treatment discomfort was lower for air polishing than ultrasonic debridement. This short-term study revealed no pertinent differences in clinical or microbiological outcomes between subgingival air polishing and ultrasonic debridement of moderate deep pockets in SPT patients. © 2011 John Wiley & Sons A/S.

  13. Near-ultraviolet removal rates for subgingival dental calculus at different irradiation angles

    Science.gov (United States)

    Schoenly, Joshua E.; Seka, Wolf D.; Rechmann, Peter

    2011-07-01

    The laser ablation rate of subgingival dental calculus irradiated at a 400-nm-wavelength, 7.4-mJ pulse energy, and 85- and 20-deg irradiation angles is measured using laser triangulation. Three-dimensional images taken before and after irradiation create a removal map with 6-μm axial resolution. Fifteen human teeth with subgingival calculus are irradiated in vitro under a cooling water spray with an ~300-μm-diam, tenth-order super-Gaussian beam. The average subgingival calculus removal rates for irradiation at 85 and 20 deg are 11.1+/-3.6 and 11.5+/-5.9 μm/pulse, respectively, for depth removal and 4.5+/-1.7×105 and 4.8+/-2.3×105 μm3/pulse, respectively, for volume removal. The ablation rate is constant at each irradiation site but varies between sites because of the large differences in the physical and optical properties of calculus. Comparison of the average depth- and volume-removal rates does not reveal any dependence on the irradiation angle and is likely due to the surface topology of subgingival calculus samples that overshadows any expected angular dependence.

  14. Subgingival microbiome in smokers and non-smokers in Korean chronic periodontitis patients.

    Science.gov (United States)

    Moon, J-H; Lee, J-H; Lee, J-Y

    2015-06-01

    Smoking is a major environmental factor associated with periodontal diseases. However, we still have a very limited understanding of the relationship between smoking and subgingival microflora in the global population. Here, we investigated the composition of subgingival bacterial communities from the pooled plaque samples of smokers and non-smokers, 134 samples in each group, in Korean patients with moderate chronic periodontitis using 16S rRNA gene-based pyrosequencing. A total of 17,927 reads were analyzed and classified into 12 phyla, 126 genera, and 394 species. Differences in bacterial communities between smokers and non-smokers were examined at all phylogenetic levels. The genera Fusobacterium, Fretibacterium, Streptococcus, Veillonella, Corynebacterium, TM7, and Filifactor were abundant in smokers. On the other hand, Prevotella, Campylobacter, Aggregatibacter, Veillonellaceae GQ422718, Haemophilus, and Prevotellaceae were less abundant in smokers. Among species-level taxa occupying > 1% of whole subgingival microbiome of smokers, higher abundance (≥ 2.0-fold compared to non-smokers) of seven species or operational taxonomic units (OTUs) was found: Fusobacterium nucleatum, Neisseria sicca, Neisseria oralis, Corynebacterium matruchotii, Veillonella dispar, Filifactor alocis, and Fretibacterium AY349371. On the other hand, lower abundance of 11 species or OTUs was found in smokers: Neisseria elongata, six Prevotella species or OTUs, Fusobacterium canifelinum, Aggregatibacter AM420165, Selenomonas OTU, and Veillonellaceae GU470897. Species richness and evenness were similar between the groups whereas diversity was greater in smokers than non-smokers. Collectively, the results of the present study indicate that differences exist in the subgingival bacterial community between smoker and non-smoker patients with chronic moderate periodontitis in Korea, suggesting that cigarette smoking considerably affects subgingival bacterial ecology. © 2014 John Wiley & Sons

  15. Autofluorescence in samples obtained from chronic biofilm infections – “all that glitters is not gold”

    DEFF Research Database (Denmark)

    Eickhardt-Dalbøge, Steffen Robert; Kragh, Kasper N.; Schrøder, Stine

    2015-01-01

    When looking at tissue sections of ex vivo samples, autofluorescence can be a major cause of artifacts and misinterpretations. We here reiterate evidence that autofluorescing granules, often hemosiderin but also ceroid or mucinogen granules, are severe obstacles when imaging and diagnosing biofilm...

  16. Biofilm Morphotypes and Population Structure among Staphylococcus epidermidis from Commensal and Clinical Samples.

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    Llinos G Harris

    Full Text Available Bacterial species comprise related genotypes that can display divergent phenotypes with important clinical implications. Staphylococcus epidermidis is a common cause of nosocomial infections and, critical to its pathogenesis, is its ability to adhere and form biofilms on surfaces, thereby moderating the effect of the host's immune response and antibiotics. Commensal S. epidermidis populations are thought to differ from those associated with disease in factors involved in adhesion and biofilm accumulation. We quantified the differences in biofilm formation in 98 S. epidermidis isolates from various sources, and investigated population structure based on ribosomal multilocus typing (rMLST and the presence/absence of genes involved in adhesion and biofilm formation. All isolates were able to adhere and form biofilms in in vitro growth assays and confocal microscopy allowed classification into 5 biofilm morphotypes based on their thickness, biovolume and roughness. Phylogenetic reconstruction grouped isolates into three separate clades, with the isolates in the main disease associated clade displaying diversity in morphotype. Of the biofilm morphology characteristics, only biofilm thickness had a significant association with clade distribution. The distribution of some known adhesion-associated genes (aap and sesE among isolates showed a significant association with the species clonal frame. These data challenge the assumption that biofilm-associated genes, such as those on the ica operon, are genetic markers for less invasive S. epidermidis isolates, and suggest that phenotypic characteristics, such as adhesion and biofilm formation, are not fixed by clonal descent but are influenced by the presence of various genes that are mobile among lineages.

  17. The antibacterial effect of photodynamic therapy in dental plaque-derived biofilms

    Science.gov (United States)

    Fontana, C. R.; Abernethy, A. D.; Som, S.; Ruggiero, K.; Doucette, S.; Marcantonio, R. C.; Boussios, C. I.; Kent, R.; Goodson, J. M.; Tanner, A. C. R.; Soukos, N. S.

    2009-01-01

    Background and Objective Photodynamic therapy (PDT) has been advocated as an alternative to antimicrobial agents to suppress subgingival species and treat periodontitis. Bacteria located within dense biofilms, such as those encountered in dental plaques, have been found to be relatively resistant to antimicrobial therapy. In the present study, we investigated the ability of PDT to affect bacteria resistant in biofilms by comparing the photodynamic effects of methylene blue (MB) on human dental plaque microorganisms in planktonic phase and in biofilms. Material and Methods Dental plaque samples were obtained from 10 subjects with chronic periodontitis. Suspensions of plaque microorganisms from 5 subjects were sensitized with MB (25 μg/ml) for 5 minutes followed by exposure to red light. Multi-species microbial biofilms developed from the same plaque samples were also exposed to MB (25 μg/ml) and the same light conditions as their planktonic counterparts. In a second set of experiments, biofilms were developed with plaque bacteria from 5 subjects and sensitized with 25 and 50 μg/ml MB followed by exposure to light as above. After PDT, survival fractions were calculated from colony-forming unit counts. Results In suspension, PDT produced approximately 63% killing of bacteria. In biofilms, the effect of PDT resulted in much lower reductions of microorganisms (32% maximal killing). Conclusion Oral bacteria in biofilms are less affected by PDT than bacteria in planktonic phase. The antibacterial effect of PDT is reduced in biofilm bacteria but not to the same degree as has been reported for treatment with antibiotics under similar conditions. PMID:19602126

  18. Detection of Intracellular Adhesion (ica and Biofilm Formation Genes in Staphylococcus aureus Isolates from Clinical Samples

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    Khadije Rezaie Keikhaie

    2017-02-01

    Full Text Available Introduction: Nosocomial infections that result in the formation of biofilms on the surfaces of biomedical implants are a leading cause of sepsis and are often associated with colonization of the implants by Staphylococcus epidermidis. Biofilm formation is thought to require two sequential steps: adhesion of cells to a solid substrate followed by cell-cell adhesion, creating multiple layers of cells. Intercellular adhesion requires the polysaccharide intercellular adhesion (PIA, which is composed of linear β-1, 6-linked glucosaminylglycans and can be synthesized in vitro from UDP-N-acetylglucosamine by products of the intercellular adhesion (ica locus. We have investigated a variety of Staphylococcus aureus strains and find that all strains tested contain the ica locus and that several can form biofilms in vitro. Material and Method: A total of 31 clinical S. aureus isolates were collected from Zabol, Iran. In vitro biofilm formation ability was determined by microliter tissue culture plates. All clinical isolates were examined for determination the ica locus by using PCR method. Result: The results of this study showed that 40 strains of Staphylococcus aureus, 12 strains carrying the gene Cocos icaA (30% and 8 strains carrying the gene icaD (20% and the number of five strains (12.5% containing both genes ica A and has been ica D. Conclusions:  S. aureus clinical isolates have different ability to form biofilm. This may be caused by the differences in the expression of biofilm related genes, genetic make-up and physiological conditions.

  19. Oral biofilm architecture on natural teeth.

    Directory of Open Access Journals (Sweden)

    Vincent Zijnge

    Full Text Available Periodontitis and caries are infectious diseases of the oral cavity in which oral biofilms play a causative role. Moreover, oral biofilms are widely studied as model systems for bacterial adhesion, biofilm development, and biofilm resistance to antibiotics, due to their widespread presence and accessibility. Despite descriptions of initial plaque formation on the tooth surface, studies on mature plaque and plaque structure below the gum are limited to landmark studies from the 1970s, without appreciating the breadth of microbial diversity in the plaque. We used fluorescent in situ hybridization to localize in vivo the most abundant species from different phyla and species associated with periodontitis on seven embedded teeth obtained from four different subjects. The data showed convincingly the dominance of Actinomyces sp., Tannerella forsythia, Fusobacterium nucleatum, Spirochaetes, and Synergistetes in subgingival plaque. The latter proved to be new with a possibly important role in host-pathogen interaction due to its localization in close proximity to immune cells. The present study identified for the first time in vivo that Lactobacillus sp. are the central cells of bacterial aggregates in subgingival plaque, and that Streptococcus sp. and the yeast Candida albicans form corncob structures in supragingival plaque. Finally, periodontal pathogens colonize already formed biofilms and form microcolonies therein. These in vivo observations on oral biofilms provide a clear vision on biofilm architecture and the spatial distribution of predominant species.

  20. Dental biofilm infections - an update.

    Science.gov (United States)

    Larsen, Tove; Fiehn, Nils-Erik

    2017-04-01

    Teeth are colonized by oral bacteria from saliva containing more than 700 different bacterial species. If removed regularly, the dental biofilm mainly comprises oral streptococci and is regarded as resident microflora. But if left undisturbed, a complex biofilm containing up to 100 bacterial species at a site will build up and may eventually cause development of disease. Depending on local ecological factors, the composition of the dental biofilm may vary considerably. With access to excess carbohydrates, the dental biofilm will be dominated by mainly gram-positive carbohydrate-fermenting bacteria causing demineralization of teeth, dental caries, which may further lead to inflammation and necrosis in the pulp and periapical region, i.e., pulpitis and periapical periodontitis. In supra- and subgingival biofilms, predominantly gram-negative, anaerobic proteolytic bacteria will colonize and cause gingival inflammation and breakdown of supporting periodontal fibers and bone and ultimately tooth loss, i.e., gingivitis, chronic or aggressive periodontitis, and around dental implants, peri-implantitis. Furthermore, bacteria from the dental biofilm may spread to other parts of the body by bacteremia and cause systemic disease. Basically, prevention and treatment of dental biofilm infections are achieved by regular personal and professional removal of the dental biofilm. © 2017 APMIS. Published by John Wiley & Sons Ltd.

  1. Changes in subgingival microflora after placement and removal of fixed orthodontic appliances

    Directory of Open Access Journals (Sweden)

    Živković-Sandić Marija

    2014-01-01

    Full Text Available Introduction. The placement of fixed orthodontic appliances may lead to increased plaque accumulation and changes in subgingival microflora. Objective. The aim of this study was to examine the changes in frequency of subgingival microflora that occur after placement and removal of fixed orthodontic appliance using polymerase chain reaction (PCR. Methods. This study included 33 orthodontic patients, who were divided into two groups. Subgingival plaque samples were collected from the right upper incisor (U1 and right upper first molar (U6. In group A, the samples were taken three times: before placement appliance (T1, after one month (T2, and after 3 months (T3. In group B the samples were also taken three times: before appliance removal (T1, after one month (T2, and after three months (T3. PCR method was used to determine the presence of P. gingivalis, A. actinomycetemcomitans, T. forsythia, and P. intermedia. Results. In group A the frequency of P. gingivalis showed statistically significant decrease at U1 (p=0.049 and U6 (p=0.008, from T1 to T2, and at U1 (p=0.048 from T1 to T3. In group B only the frequency of T. forsythia showed a statistically significant decrease, at U6 (T1 vs. T2, p=0.004; T1 vs. T3, p=0.0003. Regarding other analyzed bacteria, changes in the presence were noticed but no statistical significance was found. Conclusion. Placement of fixed appliances may have an impact on subgingival microflora, but in the first months after the placement and removal of the appliance changes were not significant, probably due to good oral hygiene. [Projekat Ministarstva nauke Republike Srbije, br. 175075

  2. The microbial community shifts of subgingival plaque in patients with generalized aggressive periodontitis following non-surgical periodontal therapy: a pilot study.

    Science.gov (United States)

    Han, Jing; Wang, Peng; Ge, Shaohua

    2017-02-07

    The object of this study is to characterize the bacterial community of subgingival plaque of two subjects with generalized aggressive periodontitis (GAgP) pre- and post-treatment. We picked two patients with GAgP and used high-throughput 16S rDNA sequencing. V4 hypervariable region was picked for PCR amplification of subgingival samples. Then, the PCR products were sequenced through Illumina MiSeq platform. One month after therapy, both the clinical features and periodontal parameters improved obviously. Moreover, the composition and structure of subgingival bacterial community changed after initial periodontal therapy. Also, the composition of the subgingival microbiota was highly individualized among different patients. Bacteroidetes, Spirochaetes and Fusobacteria were related to pathogenicity of GAgP while Actinobacteria and Proteobacteria seemed associated with clinical symptoms resolution. In this study, we found the subgingival bacterial community was high in species richness but dominated by a few species or phylotypes, with significant shifts of microbiota that occurred after treatment. This study demonstrated the shift of the subgingival bacterial community before and after treatment by high-throughput 16S rDNA sequencing, and provided a concise method for analysis of microbial community for periodontal diseases.

  3. [Study on Microbial Diversity of Peri-implantitis Subgingival by High-throughput Sequencing].

    Science.gov (United States)

    Li, Zhi-jie; Wang, Shao-guo; Li, Yue-hong; Tu, Dong-xiang; Liu, Shi-yun; Nie, Hong-bing; Li, Zhi-qiang; Zhang, Ju-mei

    2015-07-01

    To study microbial diversity of peri-implantitis subgingival with high-throughput sequencing, and investigate microbiological etiology of peri-implantitis. Subgingival plaques were sampled from the patients with peri-implantitis (D group) and non-peri-implantitis subjects (N group). The microbiological diversity of the subgingival plaques was detected by sequencing V4 region of 16S rRNA with Illumina Miseq platform. The diversity of the community structure was analyzed using Mothur software. A total of 156 507 gene sequences were detected in nine samples and 4 402 operational taxonomic units (OTUs) were found. Selenomonas, Pseudomonas, and Fusobacterium were dominant bacteria in D group, while Fusobacterium, Veillonella and Streptococcus were dominant bacteria in N group. Differences between peri-implantitis and non-peri-implantitis bacterial communities were observed at all phylogenetic levels by LEfSe, which was also found in PcoA test. The occurrence of peri-implantitis is not only related to periodontitis pathogenic microbe, but also related with the changes of oral microbial community structure. Treponema, Herbaspirillum, Butyricimonas and Phaeobacte may be closely related to the occurrence and development of peri-implantitis.

  4. Subgingival Microbiota in White Patients With Desquamative Gingivitis: A Cross-Sectional Study.

    Science.gov (United States)

    Arduino, Paolo G; Romano, Federica; Sasia, Danilo; Broccoletti, Roberto; Ricceri, Fulvio; Barbui, Anna Maria; Brossa, Silvia; Cipriani, Raffaella; Cricenti, Luca; Cabras, Marco; Aimetti, Mario

    2017-07-01

    Presence of epithelial desquamation, erythema, and erosions on gingival tissue is usually described in the literature as desquamative gingivitis (DG). A wide range of autoimmune/dermatologic disorders can manifest as DG, although the two more common are oral lichen planus and mucous membrane pemphigoid. The aim of this study is to investigate prevalence of 11 periodontopathogenic microorganisms in patients with DG and to compare it with the microbiologic status of individuals affected by plaque-induced gingivitis (pGI). Cross-sectional clinical and microbiologic data were obtained from 66 patients (33 in each group). Subgingival plaque samples were analyzed using semiquantitative polymerase chain reaction analysis. Statistically significant difference, but with little clinical significance, was observed in gingival conditions between the two groups, probably due to the worse home control hygiene of patients with DG. Prevalence and levels of Aggregatibacter actinomycetemcomitans, Eikenella corrodens, and Fusobacterium nucleatum/periodonticum were statistically higher in samples from patients with DG than in those with pGI. In multivariate regression models, subgingival colonization of A. actinomycetemcomitans and F. nucleatum/periodonticum was not statistically associated with DG, whereas, high levels of E. corrodens were associated with 13-fold increased odds for DG. Microbiologic differences were found in subgingival plaque for patients with DG and pGI. This may suggest possible association between periodontal pathogens and DG.

  5. Effect of triclosan on the subgingival microbiota of periodontitis-susceptible subjects.

    Science.gov (United States)

    Rosling, B; Dahlén, G; Volpe, A; Furuichi, Y; Ramberg, P; Lindhe, J

    1997-12-01

    The present study evaluated the long-term effect of (i) meticulous self-performed, supragingival plaque control and (ii) the use of a triclosan/copolymer containing dentifrice in adult subjects susceptible to destructive periodontitis. 40 individuals were recruited into the trial. 3-5 years prior to the baseline examination, they had all been treated by nonsurgical means- for advanced periodontal disease. During the subsequent maintenance phase, all subjects had at different time intervals exhibited sites with recurrent periodontitis. At a baseline examination, 6 surfaces per tooth were examined regarding bleeding on probing, probing pocket depth, and probing attachment level. The deepest pocket site in each quadrant (i.e. 4 sites per subject) was selected and samples of the subgingival bacteria were taken. At baseline, all volunteers received detailed information on proper oral hygiene techniques. This information was repeated on an individual need basis during the course of the subsequent 36-months. No professional subgingival therapy was delivered between the baseline and the 36-month examinations. The subjects were randomly distributed into 2 equal groups of 20 individuals each, 1 test and 1 control group. The members of the test group were supplied with a fluoridated dentifrice containing triclosan/copolymer (Total, Colgate), while the controls received a corresponding dentifrice but without triclosan/copolymer. The findings demonstrated that in subjects with advanced and recurrent periodontitis, carefully practiced supragingival plaque control had some effects on the subgingival microbiota, but also that this was insufficient to prevent disease progression. In a corresponding group of subjects, however, who used a triclosan/copolymer dentifrice, the subgingival microbiota was reduced in both quantitative and qualitative terms and recurrent periodontitis was almost entirely prevented.

  6. Alterations of the Subgingival Microbiota in Pediatric Crohn's Disease Studied Longitudinally in Discovery and Validation Cohorts.

    Science.gov (United States)

    Kelsen, Judith; Bittinger, Kyle; Pauly-Hubbard, Helen; Posivak, Leah; Grunberg, Stephanie; Baldassano, Robert; Lewis, James D; Wu, Gary D; Bushman, Frederic D

    2015-12-01

    Oral manifestations are common in Crohn's disease (CD). Here we characterized the subgingival microbiota in pediatric patients with CD initiating therapy and after 8 weeks to identify microbial community features associated with CD and therapy. Pediatric patients with CD were recruited from The Children's Hospital of Pennsylvania. Healthy control subjects were recruited from primary care or orthopedics clinic. Subgingival plaque samples were collected at initiation of therapy and after 8 weeks. Treatment exposures included 5-ASAs, immunomodulators, steroids, and infliximab. The microbiota was characterized by 16S rRNA gene sequencing. The study was repeated in separate discovery (35 CD, 43 healthy) and validation cohorts (43 CD, 31 healthy). Most subjects in both cohorts demonstrated clinical response after 8 weeks of therapy (discovery cohort 88%, validation cohort 79%). At week 0, both antibiotic exposure and disease state were associated with differences in bacterial community composition. Seventeen genera were identified in the discovery cohort as candidate biomarkers, of which 11 were confirmed in the validation cohort. Capnocytophaga, Rothia, and TM7 were more abundant in CD relative to healthy controls. Other bacteria were reduced in abundance with antibiotic exposure among CD subjects. CD-associated genera were not enriched compared with healthy controls after 8 weeks of therapy. Subgingival microbial community structure differed with CD and antibiotic use. Results in the discovery cohort were replicated in a separate validation cohort. Several potentially pathogenic bacterial lineages were associated with CD but were not diminished in abundance by antibiotic treatment, suggesting targets for additional surveillance.

  7. Evaluation of Subgingival Dental Plaque Microbiota Changes In Fixed Orthodontic Patients with Syber Green Real Time PCR

    Directory of Open Access Journals (Sweden)

    Naser Sargolzaie

    2014-06-01

    Full Text Available Introduction: One of the most common problems we confront in orthodontic therapy is periodontal diseases. Initial factor which causes these diseases is colonization of anaerobic microorganisms in subgingival plaque. Technically, local environmental changes related to orthodontic band and brackets may influence the bacterial species in periodontal plaque. However, it seems necessary to assess variations in subgingival plaque caused by orthodontic appliances. The aim of this study was to investigate changes in subgingival microbiota and clinical parameters before and after bracket placement. Methods: Clinical parameters including probing depth (PD, plaque index (PI, clinical attachment level (CAL, bleeding on probing (BOP and gingival index (GI were recorded and subgingival microbial samples were collected in 30 people aged between 13 and 25. As a control group, 15 persons getting matched as to their age and sex with no need to orthodontic treatment were opted using specific primers, SYBER Green Real-Time PCR was carried out in order to determine bacterial flora in stored samples. All mentioned procedures were reassessed in experimental group and in control group three months after band and bracket bonding. A descriptive analysis was conducted, and paired t test and Wilcoxon test were used for differences between groups (P

  8. Investigation of N-acyl homoserine lactone (AHL) molecule production in Gram-negative bacteria isolated from cooling tower water and biofilm samples.

    Science.gov (United States)

    Haslan, Ezgi; Kimiran-Erdem, Ayten

    2013-09-01

    In this study, 99 Gram-negative rod bacteria were isolated from cooling tower water, and biofilm samples were examined for cell-to-cell signaling systems, N-acyl homoserine lactone (AHL) signal molecule types, and biofilm formation capacity. Four of 39 (10 %) strains isolated from water samples and 14 of 60 (23 %) strains isolated from biofilm samples were found to be producing a variety of AHL signal molecules. It was determined that the AHL signal molecule production ability and the biofilm formation capacity of sessile bacteria is higher than planktonic bacteria, and there was a statistically significant difference between the AHL signal molecule production of these two groups (p tower water and biofilm samples produced different types of AHL signal molecules and that there were different types of AHL signal molecules in an AHL extract of bacteria. In the present study, it was observed that different isolates of the same strains did not produce the same AHLs or did not produce AHL molecules, and bacteria known as AHL producers did not produce AHL. These findings suggest that detection of signal molecules in bacteria isolated from cooling towers may contribute to prevention of biofilm formation, elimination of communication among bacteria in water systems, and blockage of quorum-sensing controlled virulence of these bacteria.

  9. Impact of supragingival therapy on subgingival microbial profile in smokers versus non-smokers with severe chronic periodontitis

    Directory of Open Access Journals (Sweden)

    Tatiana Meulman

    2012-01-01

    Full Text Available The aim of this study was to assess subgingival microbiological changes in smokers versus non-smokers presenting severe chronic periodontitis after supragingival periodontal therapy (ST.Non-smokers (n=10 and smokers (n=10 presenting at least nine teeth with probing pocket depth (PPD (≥5 mm, bleeding on probing (BoP, and no history of periodontal treatment in the last 6 months were selected. Clinical parameters assessed were plaque index (PI, BoP, PPD, relative gingival margin position (rGMP and relative clinical attachment level (rCAL. Subgingival biofilm was collected before and 21 days after ST. DNA was extracted and the 16S rRNA gene was amplified with the universal primer pair, 27F and 1492R. Amplified genes were cloned, sequenced, and identified by comparison with known 16S rRNA sequences. Statistical analysis was performed by Student's t and Chi-Square tests (α=5%.Clinically, ST promoted a significant reduction in PI and PPD, and gain of rCAL for both groups, with no significant intergroup difference. Microbiologically, at baseline, data analysis demonstrated that smokers harbored a higher proportion of Porphyromonas endodontalis, Bacteroidetes sp., Fusobacterium sp. and Tannerella forsythia and a lower number of cultivated phylotypes (p<0.05. Furthermore, non-smokers featured significant reductions in key phylotypes associated with periodontitis, whereas smokers presented more modest changes.Within the limits of the present study, ST promoted comparable clinical improvements in smokers and non-smokers with severe chronic periodontitis. However, in smokers, ST only slightly affected the subgingival biofilm biodiversity, as compared with non-smokers.

  10. Microbiological Effect of Essential Oils in Combination with Subgingival Ultrasonic Instrumentation and Mouth Rinsing in Chronic Periodontitis Patients

    Directory of Open Access Journals (Sweden)

    Toshiya Morozumi

    2013-01-01

    Full Text Available Thirty chronic periodontitis patients were randomly assigned to 3 groups: control, saline, and essential oil-containing antiseptic (EO. Subgingival plaque was collected from a total of 90 pockets across all subjects. Subsequently, subgingival ultrasonic instrumentation (SUI was performed by using EO or saline as the irrigation agent. After continuous mouth rinsing at home with EO or saline for 7 days, subgingival plaques were sampled again. Periodontopathic bacteria were quantified using the modified Invader PLUS assay. The total bacterial count in shallow pockets (probing pocket depth (PPD = 4-5 mm was significantly reduced in both saline (P<0.05 and EO groups (P<0.01. The total bacterial count (P<0.05 and Porphyromonas gingivalis (P<0.01 and Tannerella forsythia (P<0.05 count in deep pockets (PPD ≥6 mm were significantly reduced only in the EO group. In comparisons of the change ratio relative to baseline value of total bacteria counts across categories, both the saline and EO groups for PPD 4-5 mm and the EO group for PPD 6 mm showed a significantly low ratio (P<0.05. The adjunctive use of EO may be effective in reducing subgingival bacterial counts in both shallow and deep pockets. This trial is registered with UMIN Clinical Trials Registry UMIN000007484.

  11. The investigation of Helicobacter pylori in the dental biofilm and saliva samples of children with dyspeptic complaints.

    Science.gov (United States)

    Aksit Bıcak, Damla; Akyuz, Serap; Kıratlı, Binnur; Usta, Merve; Urganci, Nafiye; Alev, Burcin; Yarat, Aysen; Sahin, Fikrettin

    2017-03-21

    The oral cavity can be an extra-gastric reservoir for Helicobacter pylori (H.pylori). This can play a role in the pathogenesis of halitosis, glossitis, recurrent aphthous stomatitis, and dental caries. The present study was conducted to detect the presence of H.pylori within the dental biofilm and in saliva samples collected from children suffering from dyspepsia and children without any gastrointestinal complaints. Associations with gastric infection, halitosis, and some oral parameters were also evaluated. Seventy children (aged between 5-16) with dyspepsia were selected for the study group and control group composed of 30 healthy children without dyspepsia were also included in the study. After detailed oral and clinical examinations for oral parameters, saliva, and supragingival dental biofilm samples were collected for 16S rRNA and 23S rRNA genes detection by real-time polymerase chain reaction (RT-PCR). The presence of gastric H.pylori was evaluated in endoscopic biopsy specimens histopathologically. Halitosis was evaluated by benzoyl-DL-arginine-naphthylamid (BANA) test. Salivary S.mutans and Lactobacilli sp. counts were also carried out by commercial kits. H.pylori was histopathologically detected amongst 83% of the children with the dyspeptic condition. The detection rate of this bacteria in dental biofilm and saliva samples and halitosis were found relatively higher in the dyspeptic children rather than the control group (p  0.05). In the gastric H.pylori positive group with dyspepsia, DMFT/S and dmft/s numbers and plaque indices were found higher than the control group (p  0.05). Comparing to those with negative for both genes, in children whose dental biofilm and saliva samples were positive for both 16S rRNA and 23S rRNA genes, significantly higher results for halitosis, and DMFS numbers and significantly lower results for dmfs numbers and pH values were found (p < 0.01). Helicobacter pylori can occur in the oral cavity aside and

  12. Influence of the Periodontal Status on the Initial-Biofilm Formation on Titanium Surfaces.

    Science.gov (United States)

    Martínez-Hernández, Miryam; Olivares-Navarrete, René; Almaguer-Flores, Argelia

    2016-02-01

    Dental implants will be exposed to a complex ecosystem once they are placed in the oral cavity. The bacterial colonization and biofilm formation on these devices will depend not only on the physicochemical surface implant properties but also on the periodontal health conditions of the patients, as these devices are exposed. The aim of this study was to correlate the subgingival microbial profile with the composition of initial biofilm formed on different microstructured titanium (Ti) surfaces. Ten periodontitis and 10 periodontally healthy subjects were included in this study. The subjects wore a removable acrylic device with four different fixed Ti surfaces for 48 hours. Microbial samples of subgingival plaque and the biofilm formed on each Ti surface were individually analyzed by the checkerboard DNA-DNA hybridization technique. Despite the roughness or hydrophilicity of the Ti surfaces, a characteristic pattern of bacterial adhesion was observed on each of the study groups. However, significant differences in the proportion of the species that colonized the Ti surfaces were found between the periodontitis and periodontally healthy groups. Treponema denticola, Neisseria mucosa, Eikenella corrodens, and Tannerella forsythia were detected in higher proportions on the Ti disks placed in the periodontitis subjects, while significant higher proportions of Capnocytophaga sputigena, Fusobacterium periodonticum, Prevotella melaninogenica, and Streptococcus mitis were detected on the Ti disks placed in the periodontally healthy group. The results obtained in this study shows that the composition and the proportion of the species that initially colonize Ti surfaces are highly influenced by the periodontal status more than the surface characteristics of the Ti implant. © 2014 Wiley Periodicals, Inc.

  13. Supragingival treatment as an aid to reduce subgingival needs: a 450-day investigation

    Directory of Open Access Journals (Sweden)

    Sabrina Carvalho Gomes

    2014-01-01

    Full Text Available This study investigated the clinical effects of using a supragingival biofilm control regimen (SUPRA as a step prior to scaling and root planing (SRP. A split-mouth clinical trial was performed in which 25 subjects with periodontitis (47.2 ± 6.5 years underwent treatment (days 0-60 and monitoring (days 90-450 phases. At Day 0 (baseline treatments were randomly assigned per quadrant: SUPRA, SRP and S30SRP (SUPRA 30 days before SRP. The full-mouth visible plaque index (VPI, gingival bleeding index (GBI, periodontal probing depth (PPD, bleeding on probing (BOP, and clinical attachment loss (CAL were examined on days 0, 30, 60, 90, 120, 270, and 450. Baseline data were similar among all groups. From days 0 to 60, the groups showed similar significant decreases in VPI and GBI. Reductions in PPD for the SRP (3.39 ± 0.17 to 2.42 ± 0.16 mm and S30SRP (3.31 ± 0.11 to 2.40 ± 0.07 mm groups were greater (p < 0.05 than those for the SUPRA group. This pattern was also observed for BOP. Attachment gain was similar and greater for the SRP (3.34 ± 0.28 to 2.58 ± 0.26 mm and S30SRP (3.25 ± 0.21 to 2.54 ± 0.19 mm groups compared to the SUPRA group. Results were maintained from day 90 forward. Overall, the S30SRP treatment reduced the subgingival treatment needs in 48.16%. Performance of a SUPRA step before SRP decreased subgingival treatment needs and maintained the periodontal stability over time.

  14. Subgingival microflora and treatment in prepubertal periodontitis associated with chronic idiopathic neutropenia.

    Science.gov (United States)

    Kamma, J J; Lygidakis, N A; Nakou, M

    1998-09-01

    Prepubertal periodontitis affects both primary and permanent dentition. The purpose of this study was to examine the composition of subgingival microflora of the permanent dentition in an 11-year-old Caucasian female, who had premature exfoliation of her deciduous teeth on her 5th year of age, and the response of this condition to the antibiotic therapy and supportive periodontal care. Gingival tissues were highly inflamed and alveolar bone loss was detected radiographically. The girl had experienced frequent upper respiratory tract infections, tonsilitis and recurrent otitis media. Her mother had history of early onset periodontitis associated with chronic idiopathic neutropenia. Blood chemistry tests and immunological examinations were also performed. Subgingival plaque samples were collected from the proximal sites of permanent molars, incisors, canines and maxillary premolars. 27 different microbial species were isolated from the subgingival microflora. Among the predominant species were Porphyromonas gingivalis (17.6%-7.3%), Prevotella intermedia (12.4%-4.7%), Capnocytophaga sputigena (14.4%-10.4%), Capnocytophaga ochracea (13.2%-6.9%) and Actinobacillus actinomycetemcomitans (9.3%-5.5%). Periodontal treatment consisted of scaling, root planing in conjunction with antibiotic administration of Augmentin 312.5 mg and Flagyl 200 mg, each t.i.d. for 10 days. 3 weeks after the antibiotic therapy, bacterial samples were collected from the same sites. All the periodontal pathogens were recovered in lower levels and A.actinomycetemcomitans was almost eliminated in the 3-week period. The evaluation of clinical indices at 3, 6 and 12 months showed that periodontal treatment in conjunction with antibiotics was effective and rapidly followed by marked clinical improvement. The microbiological monitoring at 3, 6 and 12 months after antibiotic treatment and each time prior to supportive periodontal care, revealed that the periodontal pathogens fluctuated in low levels even

  15. Subgingival irrigation in the maintenance phase of periodontal therapy.

    Science.gov (United States)

    Schlagenhauf, U; Stellwag, P; Fiedler, A

    1990-10-01

    The purpose of this study was to evaluate the effect of subgingival scaling versus subgingival pocket irrigation with 0.1% chlorhexidine or saline controls on the repopulation of subgingival periodontal sites with disease-associated micro-organisms following a single procedure of scaling and root planing. Additionally, pertinent clinical parameters (attachment level, plaque index, bleeding on probing) were also recorded. 375 sites in 30 individuals with previously untreated periodontal disease were thoroughly scaled and subsequently either rescaled, irrigated, or not treated at all for the following 6 months at 1-month intervals. The results show that the initial scaling and root planing procedure led to significant clinical and microbiological improvements in all experimental groups. These improvements were maintained in all but the untreated sites. Based on the observed clinical and microbiological changes, subgingival irrigation of periodontal pockets at 1-month intervals was equally effective as scaling and root planing performed at the same pace. 0.1% chlorhexidine however, being used as test irrigant, was not more effective than saline controls.

  16. Ribotyping on small-sized spirochetes isolated from subgingival plaque

    DEFF Research Database (Denmark)

    Fiehn, N E; Bangsborg, J M; Colding, H

    1995-01-01

    In the present study DNA restriction patterns and corresponding ribotypes of 17 subgingival small-sized spirochetes (1:2:1 and 2:4:2 isolates), 2 Treponema socranskii strains and two Treponema denticola strains were examined. Purified chromosomal DNA was digested by BamHI, HindIII, PstI and ClaI....

  17. Effect of smoking on subgingival microflora of patients with periodontitis in Japan

    Directory of Open Access Journals (Sweden)

    Yamada Satoru

    2011-01-01

    Full Text Available Abstract Background Smoking is a risk factor for periodontitis. To clarify the contribution of smoking to periodontitis, it is essential to assess the relationship between smoking and the subgingival microflora. The aim of this study was to gain an insight into the influence of smoking on the microflora of Japanese patients with periodontitis. Methods Sixty-seven Japanese patients with chronic periodontitis (19 to 83 years old, 23 women and 44 men were enrolled in the present study. They consisted of 30 smokers and 37 non-smokers. Periodontal parameters including probing pocket depth (PPD and bleeding on probing (BOP and oral hygiene status were recorded. Detection of Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia, Tannerella forsythia, Fusobacterium nucleatum/periodonticum, Treponema denticola and Campylobacter rectus in subgingival plaque samples was performed by polymerase chain reaction. Association between the detection of periodontopathic bacteria and smoking status was analyzed by multiple logistic regression analysis and chi-square test. Results A statistically significant association was found between having a PPD ≥ 4 mm and detection of T. denticola, P. intermedia, T. forsythia, or C. rectus, with odds ratios ranging from 2.17 to 3.54. A significant association was noted between BOP and the detection of C. rectus or P. intermedia, and smoking, with odds ratios ranging from 1.99 to 5.62. Prevalence of C. rectus was higher in smokers than non-smokers, whereas that of A. actinomycetemcomitans was lower in smokers. Conclusions Within limits, the analysis of the subgingival microbial flora in smokers and non-smokers with chronic periodontitis suggests a relevant association between smoking and colonization by the specific periodontal pathogens including C. rectus.

  18. Effect of smoking on subgingival microflora of patients with periodontitis in Japan.

    Science.gov (United States)

    Kubota, Michiya; Tanno-Nakanishi, Mariko; Yamada, Satoru; Okuda, Katsuji; Ishihara, Kazuyuki

    2011-01-05

    Smoking is a risk factor for periodontitis. To clarify the contribution of smoking to periodontitis, it is essential to assess the relationship between smoking and the subgingival microflora. The aim of this study was to gain an insight into the influence of smoking on the microflora of Japanese patients with periodontitis. Sixty-seven Japanese patients with chronic periodontitis (19 to 83 years old, 23 women and 44 men) were enrolled in the present study. They consisted of 30 smokers and 37 non-smokers. Periodontal parameters including probing pocket depth (PPD) and bleeding on probing (BOP) and oral hygiene status were recorded. Detection of Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia, Tannerella forsythia, Fusobacterium nucleatum/periodonticum, Treponema denticola and Campylobacter rectus in subgingival plaque samples was performed by polymerase chain reaction. Association between the detection of periodontopathic bacteria and smoking status was analyzed by multiple logistic regression analysis and chi-square test. A statistically significant association was found between having a PPD ≥ 4 mm and detection of T. denticola, P. intermedia, T. forsythia, or C. rectus, with odds ratios ranging from 2.17 to 3.54. A significant association was noted between BOP and the detection of C. rectus or P. intermedia, and smoking, with odds ratios ranging from 1.99 to 5.62. Prevalence of C. rectus was higher in smokers than non-smokers, whereas that of A. actinomycetemcomitans was lower in smokers. Within limits, the analysis of the subgingival microbial flora in smokers and non-smokers with chronic periodontitis suggests a relevant association between smoking and colonization by the specific periodontal pathogens including C. rectus.

  19. Alterations of the Subgingival Microbiota in Pediatric Crohn's Disease Studied Longitudinally in Discovery and Validation Cohorts

    Science.gov (United States)

    Kelsen, Judith; Bittinger, Kyle; Pauly-Hubbard, Helen; Posivak, Leah; Grunberg, Stephanie; Baldassano, Robert; Lewis, James D; Wu, Gary D; Bushman, Frederic D

    2016-01-01

    Background Oral manifestations are common in Crohn's disease (CD). Here we characterized the subgingival microbiota in pediatric CD patients initiating therapy and after 8 weeks to identify microbial community features associated with CD and therapy. Methods Pediatric CD patients were recruited from The Children's Hospital of Pennsylvania. Healthy control subjects were recruited from primary care or orthopedics clinic. Subgingival plaque samples were collected at initiation of therapy and after 8 weeks. Treatment exposures included 5-ASAs, immunomodualtors, steroids, and infliximab. The microbiota was characterized by 16S rRNA gene sequencing. The study was repeated in separate discovery (35 CD, 43 healthy) and validation cohorts (43 CD, 31 healthy). Results A majority of subjects in both cohorts demonstrated clinical response after 8 weeks of therapy (discovery cohort 88%, validation cohort 79%). At week 0, both antibiotic exposure and disease state were associated with differences in bacterial community composition. Seventeen genera were identified in the discovery cohort as candidate biomarkers, of which 11 were confirmed in the validation cohort. Capnocytophaga, Rothia, and TM7 were more abundant in CD relative to healthy controls. Other bacteria were reduced in abundance with antibiotic exposure among CD subjects. CD-associated genera were not enriched compared to healthy controls after 8 weeks of therapy. Conclusions Subgingival microbial community structure differed with CD and antibiotic use. Results in the discovery cohort were replicated in a separate validation cohort. Several potentially pathogenic bacterial lineages were associated with CD but were not diminished in abundance by antibiotic treatment, suggesting targets for additional surveillance. PMID:26288001

  20. Subgingival microbiome in smokers and non-smokers in periodontitis: an exploratory study using traditional targeted techniques and a next-generation sequencing

    NARCIS (Netherlands)

    Bizzarro, S.; Loos, B.G.; Laine, M.L.; Crielaard, W.; Zaura, E.

    2013-01-01

    Aim To compare the results of two targeted techniques to an open-ended technique in periodontitis patients, differentiated on the basis of smoking habit. Materials & Methods Thirty periodontitis patients (15 smokers and 15 non-smokers) provided subgingival plaque samples for 16S rRNA gene amplicon

  1. Effects of systemic administration of sitafloxacin on subgingival microflora and antimicrobial susceptibility profile in acute periodontal lesions.

    Science.gov (United States)

    Tomita, Sachiyo; Kasai, Shunsuke; Ihara, Yuichiro; Imamura, Kentaro; Kita, Daichi; Ota, Koki; Kinumatsu, Takashi; Nakagawa, Taneaki; Saito, Atsushi

    2014-01-01

    The aim of this study was to assess the effect(s) of systemic administration of sitafloxacin on subgingival microbial profiles of acute periodontal lesions. Antimicrobial susceptibility of clinical isolates was also investigated. Patients with acute phases of chronic periodontitis were subjected to clinical examination and microbiological assessment of their subgingival plaque samples by culture technique. Sitafloxacin was then administered (100 mg/day for 5 days) systemically. The clinical and microbiological examinations were repeated 6-8 days after administration. Susceptibilities of clinical isolates to various antimicrobials were determined using the broth and agar dilution methods. From the sampled sites in 30 participants, a total of 355 clinical isolates (34 different bacterial species) were isolated and identified. Parvimonas micra, Prevotella intermedia and Streptococcus mitis were the most prevalent cultivable bacteria in acute sites. Systemic administration of sitafloxacin yielded a significant improvement in clinical and microbiological parameters. Among the antimicrobials tested, sitafloxacin was the most potent against the clinical isolates with an MIC90 of 0.12 μg/ml at baseline. After administration, most clinical isolates were still highly susceptible to sitafloxacin although some increase in MICs was observed. The results suggest that systemic administration of sitafloxacin is effective against subgingival bacteria isolated from acute periodontal lesions. Copyright © 2014 Elsevier Ltd. All rights reserved.

  2. Antibiotic resistance and biofilm production among the strains of Staphylococcus aureus isolated from pus/wound swab samples in a tertiary care hospital in Nepal.

    Science.gov (United States)

    Belbase, Ankit; Pant, Narayan Dutt; Nepal, Krishus; Neupane, Bibhusan; Baidhya, Rikesh; Baidya, Reena; Lekhak, Binod

    2017-03-23

    The increasing drug resistance along with inducible clindamycin resistance, methicillin resistance and biofilm production among the strains of Staphylococcus aureus are present as the serious problems to the successful treatment of the infections caused by S. aureus. So, the main objectives of this study were to determine the antimicrobial susceptibility patterns along with the rates of inducible clindamycin resistance, methicillin resistance and biofilm production among the strains of S. aureus isolated from pus/wound swab samples. A total of 830 non-repeated pus/wound swab samples were processed using standard microbiological techniques. The colonies grown were identified on the basis of colony morphology, Gram's stain and biochemical tests. Antimicrobial susceptibility testing was performed by Kirby-Bauer disc diffusion technique. Detection of inducible clindamycin resistance was performed by D test, while detection of methicillin resistant S. aureus (MRSA) was performed by determination of minimum inhibitory concentration of oxacillin by agar dilution method. Similarly, detection of biofilm formation was performed by microtiter plate method. Strains showing resistance to three or more than three different classes of antibiotics were considered multidrug resistant. Total 76 samples showed the growth of S. aureus, among which 36 (47.4%) contained MRSA and 17 (22.4%) samples were found to have S. aureus showing inducible clindamycin resistance. Among the S. aureus isolated from outpatients, 41.9% were MRSA. Highest rates of susceptibility of S. aureus were seen toward linezolid (100%) and vancomycin (100%). Similarly, S. aureus isolated from 35 (46.1%) samples were found to be biofilm producers. Higher rate of inducible clindamycin resistance was seen among MRSA in comparison to methicillin susceptible S. aureus (MSSA). Similarly, higher rates of multidrug resistance and methicillin resistance were found among biofilm producing strains in comparison to biofilm non

  3. Antibiotic resistance and biofilm formation among coagulase-negative staphylococci isolated from clinical samples at a tertiary care hospital of eastern Nepal

    Directory of Open Access Journals (Sweden)

    Lok Bahadur Shrestha

    2017-08-01

    Full Text Available Abstract Background Coagulase negative staphylococci were long regarded non-pathogenic as they are the commensals of human skin and mucosa but the recent changes in the medical practice and changes in underlying host populations, they are being considered significant pathogens associated with number of nosocomial infections. The objective of the study was to determine the species, antimicrobial susceptibility pattern, biofilm forming ability of the clinically significant CoNS isolates and to compare the different methods for the detection of biofilm formation. Methods A total of 52 clinically significant CoNS isolates obtained from different units during a year period were studied. Characterization was done using standard microbiological guidelines and antimicrobial susceptibility was done following CLSI guidelines. Biofilm formation was detected by using three methods i.e. tissue culture plate method, congo red agar method and tube adherence method. Results Among 52 isolates, S. epidermidis (52% was the most common species which was followed by S. saprophyticus (18% and S. haemolyticus (14%. Antimicrobial susceptibility pattern of CoNS documented resistance of 80% to ampicillin. Resistance to cefoxitin and ceftriaxone was observed in 58% of the isolates. Biofilm formation was observed in 65.38% of the isolates. The accuracy of Congo red agar and tube adherence method for the detection of biofilm formation was 82% and 76% respectively. Conclusion CoNS isolates obtained from clinical samples should be processed routinely and antimicrobial susceptibility testing should be performed. Multidrug-resistant CoNS are prevalent. All the three methods i.e. tissue culture plate, Congo red agar and tube adherence method can be used in detecting biofilm formation.

  4. Effect of non-surgical periodontal treatment on the subgingival microbiota of patients with chronic kidney disease

    Directory of Open Access Journals (Sweden)

    Hilana Paula Carillo Artese

    2012-08-01

    Full Text Available This study investigated the effect of non-surgical periodontal therapy on the composition of subgingival microbiota of patients with chronic kidney disease (CKD. Sixteen CKD pre-dialysis individuals (CKD and 14 individuals without clinical evidence of kidney disease (C presenting chronic periodontitis were treated by scaling and root planing. Subgingival samples were collected from each patient and analyzed for their composition by checkerboard at baseline and 3 months post-therapy. Significant differences between groups at baseline were sought by the Mann-Whitney and χ² tests. Changes over time were examined by the Wilcoxon test. At baseline, the CKD group had significantly lower counts of E. faecalis compared to the C group (p < 0.05. After treatment, the levels of a greater number of species were reduced in the C group. Higher levels of A. israelii, C. rectus, F. periodonticum, P. micra, P. nigrescens, T. forsythia, N. mucosa, and S. anginosus (p < 0.05 were found in the CKD group compared to the C group. Also, non-responsive sites in CKD individuals harbored significantly higher levels of pathogenic species (T. forsythia, P. gingivalis, T. denticola, Fusobacterium spp., D. pneumosintes, E. faecalis and S. aureus; p < 0.05 than sites that responded to therapy, as well as non-responsive sites in the C group. The periodontitis-associated subgingival microbiota of CKD and systemically healthy individuals was similar in composition. However, high levels of pathogenic species persisted in the subgingival microbiota of patients with CKD after treatment.

  5. Evaluation of a novel immunochromatographic device for rapid and accurate clinical detection of Porphyromonas gingivalis in subgingival plaque.

    Science.gov (United States)

    Imamura, K; Takayama, S; Saito, A; Inoue, E; Nakayama, Y; Ogata, Y; Shirakawa, S; Nagano, T; Gomi, K; Morozumi, T; Akiishi, K; Watanabe, K; Yoshie, H

    2015-10-01

    An important goal for the improved diagnosis and management of infectious and inflammatory diseases, such as periodontitis, is the development of rapid and accurate technologies for the decentralized detection of bacterial pathogens. The aim of this prospective multicenter study was to evaluate the clinical use of a novel immunochromatographic device with monoclonal antibodies for the rapid point-of-care detection and semi-quantification of Porphyromonas gingivalis in subgingival plaque. Sixty-three patients with chronic periodontitis and 28 periodontally healthy volunteers were subjected to clinical and microbiological examinations. Subgingival plaque samples were analyzed for the presence of P. gingivalis using a novel immunochromatography based device DK13-PG-001, designed to detect the 40k-outer membrane protein of P. gingivalis, and compared with a PCR-Invader method. In the periodontitis group, a significant strong positive correlation in detection results was found between the test device score and the PCR-Invader method (Spearman rank correlation, r=0.737, pgingivalis, whereas 76% (n=48) of periodontitis subjects were tested positive. There was a significant positive correlation between device scores for P. gingivalis and periodontal parameters including probing pocket depth and clinical attachment level (r=0.317 and 0.281, respectively, pgingivalis in subgingival plaque. UMIN Clinical Trials Registry (UMIN-CTR) UMIN000011943. Copyright © 2015 Elsevier B.V. All rights reserved.

  6. Effect of cigarette smoking on subgingival bacteria in healthy subjects and patients with chronic periodontitis

    OpenAIRE

    Karasneh, Jumana,; Al Habashneh, Rola ,; Marzouka, Nour Aldain,; Thornhill, Martin,

    2016-01-01

    Background Cigarette smoking is known to increase the risk of periodontal destruction and developing chronic periodontitis (CP). It is also reported to affect the subgingival bacterial profile among CP patients. However, studies on the effect of smoking on the bacterial profile among healthy subjects are still limited. Therefore, the aim of this study was to investigate the impact of smoking on the subgingival bacterial profile in both healthy adults and CP patients. Methods Subgingival plaqu...

  7. Combating biofilms

    DEFF Research Database (Denmark)

    Yang, Liang; Liu, Yang; Wu, Hong

    2012-01-01

    Biofilms are complex microbial communities consisting of microcolonies embedded in a matrix of self-produced polymer substances. Biofilm cells show much greater resistance to environmental challenges including antimicrobial agents than their free-living counterparts. The biofilm mode of life...... is believed to significantly contribute to successful microbial survival in hostile environments. Conventional treatment, disinfection and cleaning strategies do not proficiently deal with biofilm-related problems, such as persistent infections and contamination of food production facilities. In this review......, strategies to control biofilms are discussed, including those of inhibition of microbial attachment, interference of biofilm structure development and differentiation, killing of biofilm cells and induction of biofilm dispersion....

  8. Relative proportions of pathogen-related oral spirochetes (PROS) and Treponema denticola in supragingival and subgingival plaque from patients with periodontitis.

    Science.gov (United States)

    Riviere, G R; Elliot, K S; Adams, D F; Simonson, L G; Forgas, L B; Nilius, A M; Lukehart, S A

    1992-02-01

    The purpose of this study was to use monoclonal antibodies to enumerate spirochetes in dental plaque, including the newly recognized pathogen-related oral spirochete (PROS) and specific serovars of Treponema denticola. Plaque was collected from control subjects with no apparent periodontal disease and from sites of moderate to severe chronic periodontitis in patients with inflammatory periodontal disease. Individual monoclonal antibodies were used to determine whether spirochetes were present and then a double-staining protocol was employed to count total spirochetes and specific treponemes in individual microscopic fields. Results indicate that spirochetes are more common at diseased sites and in subgingival plaque than at healthy sites or in supragingival plaque. Together PROS and T. denticola comprised the majority of all spirochetes in all samples and PROS and T. denticola serovars "B" and D were most numerous in plaque from patients with periodontitis. PROS were the majority of all spirochetes in supragingival plaque (76.2% +/- 23.8%) and subgingival plaque (60.9% +/- 19.1%) from periodontitis patients, significantly larger than the percentage of T. denticola serovar "B" (P less than .001 for both supragingival and subgingival plaque) and serovar D (P less than .01 for supragingival and P less than .001 for subgingival plaque). These observations indicate that PROS are the predominant spirochete in plaque from sites of patients with periodontitis, but other analytical approaches are necessary to determine if PROS or T. denticola are pathogenic.

  9. Immediate effect of instrumentation on the subgingival microflora in deep inflamed pockets under strict plaque control

    NARCIS (Netherlands)

    Rhemrev, GE; Timmerman, MF; Veldkamp, A; Van Winkelhoff, AJ; Van der Velden, U

    Objective: To investigate (1) reduction in the number of microorganisms obtained directly after subgingival instrumentation, (2) rate of bacterial re-colonization during 2 weeks, under supragingival plaque-free conditions. Materials and Method: Effects of subgingival instrumentation were measured at

  10. Relative abundance of total subgingival plaque-specific bacteria in salivary microbiota reflects the overall periodontal condition in patients with periodontitis.

    Science.gov (United States)

    Kageyama, Shinya; Takeshita, Toru; Asakawa, Mikari; Shibata, Yukie; Takeuchi, Kenji; Yamanaka, Wataru; Yamashita, Yoshihisa

    2017-01-01

    Increasing attention is being focused on evaluating the salivary microbiota as a promising method for monitoring oral health; however, its bacterial composition greatly differs from that of dental plaque microbiota, which is a dominant etiologic factor of oral diseases. This study evaluated the relative abundance of subgingival plaque-specific bacteria in the salivary microbiota and examined a relationship between the abundance and severity of periodontal condition in patients with periodontitis. Four samples (subgingival and supragingival plaques, saliva, and tongue coating) per each subject were collected from 14 patients with a broad range of severity of periodontitis before periodontal therapy. The bacterial composition was analyzed by 16S rRNA gene amplicon sequencing using Ion PGM. Of the 66 species-level operational taxonomic units (OTUs) representing the mean relative abundance of ≥ 1% in any of the four niches, 12 OTUs corresponding to known periodontal pathogens, including Porphyromonas gingivalis, were characteristically predominant in the subgingival plaque and constituted 37.3 ± 22.9% of the microbiota. The total relative abundance of these OTUs occupied only 1.6 ± 1.2% of the salivary microbiota, but significantly correlated with the percentage of diseased sites (periodontal pocket depth ≥ 4 mm; r = 0.78, P microbiota (r = 0.61, P = 0.02). After periodontal therapy, the total relative abundance of these 12 OTUs was evaluated as well as before periodontal therapy and reductions of the abundance through periodontal therapy were strongly correlated in saliva and subgingival plaque (r = 0.81, P microbiota might be a promising target for the evaluation of subgingival plaque-derived bacteria representing the present condition of periodontal health.

  11. Changes in antimicrobial susceptibility profile and prevalence of quinolone low-sensitive strains in subgingival plaque from acute periodontal lesions after systemic administration of sitafloxacin.

    Science.gov (United States)

    Tomita, Sachiyo; Kasai, Shunsuke; Imamura, Kentaro; Ihara, Yuichiro; Kita, Daichi; Ota, Koki; Sekino, Jin; Nakagawa, Taneaki; Saito, Atsushi

    2015-02-01

    This study aimed to assess changes in antimicrobial susceptibilities of subgingival bacteria in acute periodontal lesions following systemic administration of a new-generation fluoroquinolone, sitafloxacin and to monitor the occurrence and fate of quinolone low-sensitive strains. Patients with acute phase of chronic periodontitis were subjected to microbiological assessment of their subgingival plaque samples at baseline (A1). Sitafloxacin was then administered systemically (100 mg/day for 5 days). The microbiological examinations were repeated one week after administration (A2). Susceptibilities of clinical isolates from acute sites to various antimicrobials were determined using broth and agar dilution methods. At A2, subgingival bacteria with low sensitivity to levofloxacin were identified in four patients, and they were subjected to a follow-up microbiological examination at on the average 12 months after sitafloxacin administration (A3). The patients received initial and supportive periodontal therapy during the period A2 to A3. From the examined subgingival sites, 8 and 19 clinical isolates were obtained at A2 and A3, respectively. Some Streptococcus strains isolated at A2 were found to be resistant to levofloxacin (MIC 16-64 μg/ml), azithromycin (MIC 2->128 μg/ml) or clarithromycin (MIC 1->32 μg/ml). At A3, isolated streptococci were highly susceptible to levofloxacin (MIC 0.5-2 μg/ml), while those resistant to azithromycin or clarithromycin were still isolated. It is suggested that the presence of the quinolone low-sensitive strains in initially acute lesions after sitafloxacin administration was transient, and they do not persist in the subgingival milieu during the periodontal therapy. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. Microbial Profile of Supragingival and Subgingival Plaque of Patients With Glycogen Storage Disease

    Directory of Open Access Journals (Sweden)

    Chealsea E. Garcia DDS, MS

    2016-12-01

    Full Text Available Patients with glycogen storage disease (GSD are either orally fed (ORF or gastronomy-tube fed (GTF with cornstarch to maintain normal glucose levels. It is not known whether the use of cornstarch affects the microbiological oral profile of patients with GSD. Thus, the purpose of this study was to compare supragingival and subgingival plaque samples collected from 53 participants with GSD (2-56 years—29 ORF and 24 GTF. The 16S sequence bacterial profiles of plaque DNA were obtained and a total of 768 probes were detected across the plaque groups. Orally fed patients showed higher means of cariogenic species and periodontal health-associated species, whereas GTF patients showed higher means of periopathogenic species ( P < .05. Orally fed patients exhibited high levels of caries pathogens and lower levels of periodontal pathogens possibly due to the acidic environment created by their cornstarch diet, when compared to GTF patients.

  13. Subgingival bacteria in Ghanaian adolescents with or without progression of attachment loss

    Directory of Open Access Journals (Sweden)

    Gunnar Dahlén

    2014-05-01

    Full Text Available Objective: This study describes subgingival bacterial profiles associated with clinical periodontal status in Ghanaian adolescents with or without progression of attachment loss. Materials and methods: Among 500 adolescents included in a cohort study, 397 returned 2 years later for a periodontal re-examination, including full-mouth CAL measurements. At follow-up, a subgroup of 98 adolescents was also subjected to bacterial sampling with paper points at four periodontal sites (mesial aspect of 11, 26, 31, and 46 and analyzed with the checkerboard DNA–DNA hybridization technique against DNA-probes from nine periodontitis-associated bacterial species. Results: The 98 Ghanaian adolescents examined in the present study were similar to the entire group examined at the 2-year follow-up with respect to age, gender, and CAL ≥3 mm. A high detection frequency of Fusobacterium nucleatum and Prevotella intermedia (>99% using checkerboard analysis was found, while for Aggregatibacter actinomycetemcomitans the detection frequency was <50%. A strong correlation was found at the individual level between the presence of P. intermedia and the total CAL change, and P. intermedia and Porphyromonas gingivalis were strongly correlated with a change in CAL and probing pocket depth (PPD at the sampled sites. In a linear regression model, a significant discriminating factor for the total CAL change in the dentition during the 2-year follow-up period was obtained for P. intermedia and public school. Conclusion: This study indicates that subgingival bacterial species other than A. actinomycetemcomitans, for example, P. intermedia, have a significant association with periodontal breakdown (change in CAL in Ghanaian adolescents with progression of periodontal attachment loss.

  14. Reliability of recordings of subgingival calculus detected using an ultrasonic device.

    Science.gov (United States)

    Corraini, Priscila; López, Rodrigo

    2015-04-01

    To assess the intra-examiner reliability of recordings of subgingival calculus detected using an ultrasonic device, and to investigate the influence of subject-, tooth- and site-level factors on the reliability of these subgingival calculus recordings. On two occasions, within a 1-week interval, 147 adult periodontitis patients received a full-mouth clinical periodontal examination by a single trained examiner. Duplicate subgingival calculus recordings, in six sites per tooth, were obtained using an ultrasonic device for calculus detection and removal. Agreement was observed in 65 % of the 22,584 duplicate subgingival calculus recordings, ranging 45 % to 83 % according to subject. Using hierarchical modeling, disagreements in the subgingival calculus duplicate recordings were more likely in all other sites than the mid-buccal, and in sites harboring supragingival calculus. Disagreements were less likely in sites with PD ≥  4 mm and with furcation involvement  ≥  degree 2. Bleeding on probing or suppuration did not influence the reliability of subgingival calculus. At the subject-level, disagreements were less likely in patients presenting with the highest and lowest extent categories of the covariate subgingival calculus. The reliability of subgingival calculus recordings using the ultrasound technology is reasonable. The results of the present study suggest that the reliability of subgingival calculus recordings is not influenced by the presence of inflammation. Moreover, subgingival calculus can be more reliably detected using the ultrasound device at sites with higher need for periodontal therapy, i.e., sites presenting with deep pockets and premolars and molars with furcation involvement.

  15. Antibiotic susceptibility of Aggregatibacter actinomycetemcomitans JP2 in a biofilm

    Directory of Open Access Journals (Sweden)

    Orit Oettinger-Barak

    2013-05-01

    Full Text Available Background: Localized aggressive periodontitis (LAgP is an inflammatory disease associated with specific bacteria, particularly Aggregatibacter actinomycetemcomitans, which can result in early tooth loss. The bacteria grow as a biofilm known as subgingival plaque. Treatment includes mechanical debridement of the biofilm, often associated with empirical antibiotic treatment. Objective: The aims of this study were to test in vitro the sensitivity of A. actinomycetemcomitans JP2 during planktonic and biofilm growth to doxycycline and to the combination of metronidazole and amoxicillin, which are two antibiotic protocols commonly used in clinical practice. Design: Two in vitro biofilm models were used to test the effects of the antibiotics: a static 96-well plate assay was used to investigate the effect of these antibiotics on biofilm formation whilst a flow chamber model was used to examine the effect on established biofilms. Results: Of the antibiotics tested in this model system, doxycycline was most efficacious with a minimal inhibitory concentration (MIC against planktonic cells of 0.21 mg/L and minimal biofilm inhibitory concentration (MBIC of 2.10 mg/L. The most commonly prescribed antibiotic regimen, amoxicillin + metronidazole, was much less effective against both planktonic and biofilm cells with an MIC and MBIC of 12.0 mg/L and 20.2 mg/L, respectively. A single treatment of the clinically achievable concentration of 10 mg/L doxycycline to sparse A. actinomycetemcomitans biofilms in the flow chamber model resulted in significant decreases in biofilm thickness, biovolume, and cell viability. Dense A. actinomycetemcomitans biofilms were significantly more resistant to doxycycline treatment. Low concentrations of antibiotics enhanced biofilm formation. Conclusion: A. actinomycetemcomitans JP2 homotypic biofilms were more susceptible in vitro to doxycycline than amoxicillin + metronidazole.

  16. Estimation of biofilm, proteinase & phospholipase production of the Candida species isolated from the oropharyngeal samples in HIV-infected patients

    Directory of Open Access Journals (Sweden)

    Vicky Lahkar

    2017-01-01

    Interpretation & conclusions: Although C. albicans was the most common Candida species identified in HIV positive patients, the emergence of NAC was of special concern. Virulence factors such as biofilms, proteinases and phospholipases were noted in both these groups. Further research is required for better understanding of the pathogenic role of Candida species so as to aid in therapeutic interventions.

  17. Pseudomonas aeruginosa variants obtained from veterinary clinical samples reveal a role for cyclic di-GMP in biofilm formation and colony morphology.

    Science.gov (United States)

    Brock, Maria T; Fedderly, Galya C; Borlee, Grace I; Russell, Michael M; Filipowska, Liliana K; Hyatt, Doreene R; Ferris, Ryan A; Borlee, Bradley R

    2017-10-16

    Overuse of antibiotics is contributing to an emerging antimicrobial resistance crisis. To better understand how bacteria adapt tolerance and resist antibiotic treatment, Pseudomonas aeruginosa isolates obtained from infection sites sampled from companion animals were collected and evaluated for phenotypic differences. Selected pairs of clonal isolates were obtained from individual infection samples and were assessed for antibiotic susceptibility, cyclic di-GMP levels, biofilm production, motility and genetic-relatedness. A total of 18 samples from equine, feline and canine origin were characterized. A sample from canine otitis media produced a phenotypically heterogeneous pair of P. aeruginosa isolates, 42121A and 42121B, which during growth on culture medium respectively exhibited hyper dye-binding small colony morphology and wild-type phenotypes. Antibiotic susceptibility to gentamicin and ciprofloxacin also differed between this pair of clonal isolates. Sequence analysis of gyrA, a gene known to be involved in ciprofloxacin resistance, indicated that 42121A and 42121B both contained mutations that confer ciprofloxacin resistance, but this did not explain the differences in ciprofloxacin resistance that were observed. Cyclic di-GMP levels also varied between this pair of isolates and were shown to contribute to the observed colony morphology variation and ability to form a biofilm. Our results demonstrate the role of cyclic di-GMP in generating the observed morphological phenotypes that are known to contribute to biofilm-mediated antibiotic tolerance. The generation of phenotypic diversity may go unnoticed during standard diagnostic evaluation, which potentially impacts the therapeutic strategy chosen to treat the corresponding infection and may contribute to the spread of antibiotic resistance.

  18. Permeabilizing biofilms

    Science.gov (United States)

    Soukos, Nikolaos S [Revere, MA; Lee, Shun [Arlington, VA; Doukas,; Apostolos, G [Belmont, MA

    2008-02-19

    Methods for permeabilizing biofilms using stress waves are described. The methods involve applying one or more stress waves to a biofilm, e.g., on a surface of a device or food item, or on a tissue surface in a patient, and then inducing stress waves to create transient increases in the permeability of the biofilm. The increased permeability facilitates delivery of compounds, such as antimicrobial or therapeutic agents into and through the biofilm.

  19. Medical biofilms.

    Science.gov (United States)

    Bryers, James D

    2008-05-01

    For more than two decades, Biotechnology and Bioengineering has documented research focused on natural and engineered microbial biofilms within aquatic and subterranean ecosystems, wastewater and waste-gas treatment systems, marine vessels and structures, and industrial bioprocesses. Compared to suspended culture systems, intentionally engineered biofilms are heterogeneous reaction systems that can increase reactor productivity, system stability, and provide inherent cell:product separation. Unwanted biofilms can create enormous increases in fluid frictional resistances, unacceptable reductions in heat transfer efficiency, product contamination, enhanced material deterioration, and accelerated corrosion. Missing from B&B has been an equivalent research dialogue regarding the basic molecular microbiology, immunology, and biotechnological aspects of medical biofilms. Presented here are the current problems related to medical biofilms; current concepts of biofilm formation, persistence, and interactions with the host immune system; and emerging technologies for controlling medical biofilms. Copyright 2007 Wiley Periodicals, Inc.

  20. Synergy in biofilm formation between Fusobacterium nucleatum and Prevotella species.

    Science.gov (United States)

    Okuda, Tamaki; Kokubu, Eitoyo; Kawana, Tomoko; Saito, Atsushi; Okuda, Katsuji; Ishihara, Kazuyuki

    2012-02-01

    The formation of biofilm by anaerobic, Gram-negative bacteria in the subgingival crevice plays an important role in the development of chronic periodontitis. The aim of this study was to characterize the role of coaggregation between Fusobacterium nucleatum and Prevotella species in biofilm formation. Coaggregation between F. nucleatum and Prevotella species was determined by visual assay. Effect of co-culture of the species on biofilm formation was assessed by crystal violet staining. Effect of soluble factor on biofilm formation was also examined using culture supernatant and two-compartment co-culture separated by a porous membrane. Production of autoinducer-2 (AI-2) by the organisms was evaluated using Vibrio harveyi BB170. Cells of all F. nucleatum strains coaggregated with Prevotella intermedia or Prevotella nigrescens with a score of 1-4. Addition of ethylenediamine tetraacetic acid or l-lysine inhibited coaggregation. Coaggregation disappeared after heating of P. intermedia or P. nigrescens cells, or Proteinase K treatment of P. nigrescens cells. Co-culture of F. nucleatum ATCC 25586 with P. intermedia or P. nigrescens strains increased biofilm formation compared with single culture (p Prevotella species was not related to enhancement of biofilm formation by F. nucleatum. These findings indicate that physical contact by coaggregation of F. nucleatum strains with P. intermedia or P. nigrescens plays a key role in the formation of biofilm by these strains. Copyright © 2011 Elsevier Ltd. All rights reserved.

  1. The effect of smoking on inflammatory and bone remodeling markers in gingival crevicular fluid and subgingival microbiota following periodontal therapy.

    Science.gov (United States)

    Bunaes, D F; Mustafa, M; Mohamed, H G; Lie, S A; Leknes, K N

    2017-08-01

    Periodontal health is mediated by suppressing microorganisms inducing a local inflammatory host response. Smoking may impair this process. This study compares gingival crevicular fluid levels of inflammatory and bone remodeling markers in heavy smokers and non-smokers following active and supportive periodontal therapy in patients with chronic periodontitis. Gingival crevicular fluid and subgingival plaque were collected from the deepest periodontal pocket in 50 patients, 25 smokers and 25 non-smokers, at baseline (T0), following active (T1) and 12 mo of supportive periodontal therapy (T2). Smoking status was validated measuring serum cotinine levels. Gingival crevicular fluid levels of 27 inflammatory and two bone remodeling markers were analyzed using multiplex and singleplex micro-bed immunoassays, and subgingival plaque samples using checkerboard DNA-DNA hybridization. Amounts of markers in smokers and non-smokers were compared calculating the effect size. Expression of inflammatory and bone-remodeling markers in smokers demonstrated an overall reduced effect size at T0 and T2 (p periodontal therapy (p periodontal microbial species. Except for an upregulation of interleukin-8, smokers exhibited reduced gingival crevicular fluid levels of several inflammatory markers at baseline and following active and supportive periodontal therapy. Only inflammatory responses in non-smokers adapted to periodontal therapy. Apparently, there seems to be an immunosuppressant effect of smoking regulating the local inflammatory response and bone remodeling markers captured in gingival crevicular fluid following periodontal therapy. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  2. Biofilm Infections

    DEFF Research Database (Denmark)

    Bjarnsholt, Thomas; Jensen, Peter Østrup; Moser, Claus Ernst

    A still increasing interest and emphasis on the sessile bacterial lifestyle biofilms has been seen since it was realized that the vast majority of the total microbial biomass exists as biofilms. Aggregation of bacteria was first described by Leeuwenhoek in 1677, but only recently recognized...... as being important in chronic infection. In 1993 the American Society for Microbiology (ASM) recognized that the biofilm mode of growth was relevant to microbiology. This book covers both the evidence for biofilms in many chronic bacterial infections as well as the problems facing these infections...... such as diagnostics, pathogenesis, treatment regimes and in vitro and in vivo models for studying biofilms. This is the first scientific book on biofilm infections, chapters written by the world leading scientist and clinicians. The intended audience of this book is scientists, teachers at university level as well...

  3. Age-dependent changes in Porphyromonas gingivalis and Prevotella species/phylotypes in healthy gingiva and inflamed/diseased sub-gingival sites.

    Science.gov (United States)

    Nadkarni, Mangala A; Chhour, Kim-Ly; Browne, Gina V; Byun, Roy; Nguyen, Ky-Anh; Chapple, Cheryl C; Jacques, Nicholas A; Hunter, Neil

    2015-05-01

    Early colonisation of oral surfaces by periodontal pathogens presents a significant risk factor for subsequent development of destructive disease affecting tissues that support the dentition. The aims of the present study were to establish the age-dependent relationship between sub-gingival profiles of 22 Prevotella species/phylotypes in children, adolescents and adults from an isolated Aboriginal community and, further, to use this information to identify Prevotella species that could serve as microbial risk indicators. DNA isolated from sub-gingival plaque samples (three healthy sites and three inflamed/diseased sites) from adults, adolescents and children was screened for Porphyromonas gingivalis load and 22 Prevotella species/phylotypes by species-specific PCR. A noticeable feature in adolescents was the marked increase in colonisation by P. gingivalis across all test sites. The mean number of Prevotella species/phylotypes colonising inflamed/diseased sub-gingival sites increased with age. Progressive partitioning of selected Prevotella species/phylotypes to healthy or inflamed/diseased sites was evident. Prevalence of Prevotella intermedia, Prevotella oral clone P4PB_24 and Prevotella oris increased significantly with age in diseased sites. Similarly, significant age-dependent increase in colonisation of healthy as well as inflamed/diseased sub-gingival sites was apparent for Prevotella oralis, Prevotella multiformis, Prevotella denticola, Prevotella strain P4P_53 and Prevotella oral clone BR014. Early colonisation of children by P. gingivalis, P. intermedia and Prevotella oral clone P4PB_24 provides indication of risk for subsequent development of periodontal disease. In the present study, the complexity of Prevotella species within gingival sites is explored as a basis for evaluating contribution of Prevotella species to disease.

  4. Clinical and microbiological effects of topical subgingival application of hyaluronic acid gel adjunctive to scaling and root planing in the treatment of chronic periodontitis.

    Science.gov (United States)

    Xu, Yi; Höfling, K; Fimmers, R; Frentzen, M; Jervøe-Storm, P M

    2004-08-01

    Hyaluronic acid (HA) has shown anti-inflammatory effects in gingivitis therapy. The potential benefits of local subgingival application of HA adjunctive to scaling and root planing (SRP) were evaluated in this study. Twenty patients with chronic periodontitis were included in this split-mouth study. Sulcus fluid flow rate (SFFR) and sulcus bleeding index were monitored at baseline and after 1, 2, 3, 4, 5, 6, and 12 weeks; probing depth and clinical attachment level were monitored at baseline and 6 and 12 weeks. Subgingival plaque samples were also taken at these same three appointments to determine the presence of Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia, Tannerella forsythensis, and Treponema denticola. All patients were treated with full-mouth scaling and root planing (SRP); in addition, an HA gel was administered subgingivally in the test sites every week for 6 weeks. An improvement of all clinical variables was observed (P Clinically, no difference between test and control sites could be found. No difference between test and control sites was seen in the tested microorganisms. No clinical or microbiological improvement was achieved by the adjunctive use of HA gel compared to SRP alone. Only SFFR was affected by the use of HA in terms of a more rapid reduction of SFFR in the test sites.

  5. Biofilm Dispersal

    Science.gov (United States)

    2010-01-01

    Like all sessile organisms, surface-attached communities of bacteria known as biofilms must release and disperse cells into the environment to colonize new sites. For many pathogenic bacteria, biofilm dispersal plays an important role in the transmission of bacteria from environmental reservoirs to human hosts, in horizontal and vertical cross-host transmission, and in the exacerbation and spread of infection within a host. The molecular mechanisms of bacterial biofilm dispersal are only beginning to be elucidated. Biofilm dispersal is a promising area of research that may lead to the development of novel agents that inhibit biofilm formation or promote biofilm cell detachment. Such agents may be useful for the prevention and treatment of biofilms in a variety of industrial and clinical settings. This review describes the current status of research on biofilm dispersal, with an emphasis on studies aimed to characterize dispersal mechanisms, and to identify environmental cues and inter- and intracellular signals that regulate the dispersal process. The clinical implications of biofilm dispersal and the potential therapeutic applications of some of the most recent findings will also be discussed. PMID:20139339

  6. Characterization of extracellular polymeric matrix, and treatment of Fusobacterium nucleatum and Porphyromonas gingivalis biofilms with DNase I and proteinase K

    Directory of Open Access Journals (Sweden)

    Marwan Mansoor Ali Mohammed

    2013-01-01

    Full Text Available Background: Biofilms are organized communities of microorganisms embedded in a self-produced extracellular polymeric matrix (EPM, often with great phylogenetic variety. Bacteria in the subgingival biofilm are key factors that cause periodontal diseases; among these are the Gram-negative bacteria Fusobacterium nucleatum and Porphyromonas gingivalis. The objectives of this study were to characterize the major components of the EPM and to test the effect of deoxyribonuclease I (DNase I and proteinase K. Methods: F. nucleatum and P. gingivalis bacterial cells were grown in dynamic and static biofilm models. The effects of DNase I and proteinase K enzymes on the major components of the EPM were tested during biofilm formation and on mature biofilm. Confocal laser scanning microscopy was used in observing biofilm structure. Results: Proteins and carbohydrates were the major components of the biofilm matrix, and extracellular DNA (eDNA was also present. DNase I and proteinase K enzymes had little effect on biofilms in the conditions used. In the flow cell, F. nucleatum was able to grow in partially oxygenated conditions while P. gingivalis failed to form biofilm alone in similar conditions. F. nucleatum supported the growth of P. gingivalis when they were grown together as dual species biofilm. Conclusion: DNase I and proteinase K had little effect on the biofilm matrix in the conditions used. F. nucleatum formed biofilm easily and supported the growth of P. gingivalis, which preferred anaerobic conditions.

  7. Medical Biofilms

    OpenAIRE

    Bryers, James D.

    2008-01-01

    For more than two decades, Biotechnology and Bioengineering has documented research focused on natural and engineered microbial biofilms within aquatic and subterranean ecosystems, wastewater and waste-gas treatment systems, marine vessels and structures, and industrial bioprocesses. Compared to suspended culture systems, intentionally engineered biofilms are heterogeneous reaction systems that can increase reactor productivity, system stability, and provide inherent cell: product separation....

  8. Salmonella biofilms

    NARCIS (Netherlands)

    Castelijn, G.A.A.

    2013-01-01

    Biofilm formation by Salmonellaspp. is a problem in the food industry, since biofilms may act as a persistent source of product contamination. Therefore the aim of this study was to obtain more insight in the processes involved and the factors contributing to Salmonellabiofilm formation. A

  9. Subgingival dysbiosis in smoker and non‑smoker patients with chronic periodontitis.

    Science.gov (United States)

    Coretti, Lorena; Cuomo, Mariella; Florio, Ermanno; Palumbo, Domenico; Keller, Simona; Pero, Raffaela; Chiariotti, Lorenzo; Lembo, Francesca; Cafiero, Carlo

    2017-04-01

    Periodontitis is one of the most common oral inflammatory diseases, and results in connective tissue degradation and gradual tooth loss. It manifests with formation of periodontal pockets, in which anaerobic and Gram‑negative bacteria proliferate rapidly. Consequently, alteration of the subgingival microbiota is considered the primary etiologic agent of periodontitis. Previous studies have reported that smokers are at increased risk of periodontal disease, in both prevalence and severity, indicating that smoking is a risk factor for the onset and progression of the pathology. In the present study, 16S rRNA sequencing was employed to assess the subgingival microbiota in 6 smoker patients with chronic periodontitis, 6 non‑smoker patients with chronic periodontitis and 8 healthy controls. The results demonstrated significant alterations in the microbial structure of periodontitis patients. High relative abundance of Parvimonans, Desulfubulbus, Paludibacter, Haemophilus, and Sphaerochaeta genera characterized subgingival microbiota of periodontitis patients, both smokers and non‑smokers. Due to the high precision and sensitivity of the 16S rRNA sequencing method, analysis for low‑abundant genera (including Pedobacter, Granulicatella, Paracoccus, Atopobium, Bifidobacterium, Coprococcus, Oridobacteriu, Peptococcus, Oscillospira and Akkermansia) was feasible, and revealed novel phylotypes associated with periodontitis. Of note, a major microbial community alteration was evident in smoker patients, suggesting an association between smoking and severity of subgingival dysbiosis. The present study confirmed that chronic periodontitis is a polymicrobial disease where changes in the equilibrium of subgingival microbiota contribute to severity of pathology.

  10. Evaluation of the Effect of Different Growth Media and Temperature on the Suitability of Biofilm Formation by Enterobacter cloacae Strains Isolated from Food Samples in South Africa

    OpenAIRE

    Mirriam E. Nyenje; Roland N. Ndip; Ezekiel Green

    2013-01-01

    This study evaluated the effects of growth medium, temperature, and incubation time on biofilm formation by Enterobacter cloacae strains. The ability to adhere to a surface was demonstrated using a microtiter plate adherence assay whereas the role of cell surface properties in biofilm formation was assessed using the coaggregation and autoaggregation assays. The architecture of the biofilms was examined under scanning electron microscope (SEM). All the strains adhered to the well of the micro...

  11. High-Resolution Taxonomic Profiling of the Subgingival Microbiome for Biomarker Discovery and Periodontitis Diagnosis

    Science.gov (United States)

    Szafranski, Szymon P.; Wos-Oxley, Melissa L.; Vilchez-Vargas, Ramiro; Jáuregui, Ruy; Plumeier, Iris; Klawonn, Frank; Tomasch, Jürgen; Meisinger, Christa; Kühnisch, Jan; Sztajer, Helena; Pieper, Dietmar H.

    2014-01-01

    The oral microbiome plays a key role for caries, periodontitis, and systemic diseases. A method for rapid, high-resolution, robust taxonomic profiling of subgingival bacterial communities for early detection of periodontitis biomarkers would therefore be a useful tool for individualized medicine. Here, we used Illumina sequencing of the V1-V2 and V5-V6 hypervariable regions of the 16S rRNA gene. A sample stratification pipeline was developed in a pilot study of 19 individuals, 9 of whom had been diagnosed with chronic periodontitis. Five hundred twenty-three operational taxonomic units (OTUs) were obtained from the V1-V2 region and 432 from the V5-V6 region. Key periodontal pathogens like Porphyromonas gingivalis, Treponema denticola, and Tannerella forsythia could be identified at the species level with both primer sets. Principal coordinate analysis identified two outliers that were consistently independent of the hypervariable region and method of DNA extraction used. The linear discriminant analysis (LDA) effect size algorithm (LEfSe) identified 80 OTU-level biomarkers of periodontitis and 17 of health. Health- and periodontitis-related clusters of OTUs were identified using a connectivity analysis, and the results confirmed previous studies with several thousands of samples. A machine learning algorithm was developed which was trained on all but one sample and then predicted the diagnosis of the left-out sample (jackknife method). Using a combination of the 10 best biomarkers, 15 of 17 samples were correctly diagnosed. Training the algorithm on time-resolved community profiles might provide a highly sensitive tool to detect the onset of periodontitis. PMID:25452281

  12. A Biofilm Pocket Model to Evaluate Different Non-Surgical Periodontal Treatment Modalities in Terms of Biofilm Removal and Reformation, Surface Alterations and Attachment of Periodontal Ligament Fibroblasts

    Science.gov (United States)

    Hägi, Tobias T.; Klemensberger, Sabrina; Bereiter, Riccarda; Nietzsche, Sandor; Cosgarea, Raluca; Flury, Simon; Lussi, Adrian; Sculean, Anton; Eick, Sigrun

    2015-01-01

    Background and Aim There is a lack of suitable in vitro models to evaluate various treatment modalities intending to remove subgingival bacterial biofilm. Consequently, the aims of this in vitro-study were: a) to establish a pocket model enabling mechanical removal of biofilm and b) to evaluate repeated non-surgical periodontal treatment with respect to biofilm removal and reformation, surface alterations, tooth hard-substance-loss, and attachment of periodontal ligament (PDL) fibroblasts. Material and Methods Standardized human dentin specimens were colonized by multi-species biofilms for 3.5 days and subsequently placed into artificially created pockets. Non-surgical periodontal treatment was performed as follows: a) hand-instrumentation with curettes (CUR), b) ultrasonication (US), c) subgingival air-polishing using erythritol (EAP) and d) subgingival air-polishing using erythritol combined with chlorhexidine digluconate (EAP-CHX). The reduction and recolonization of bacterial counts, surface roughness (Ra and Rz), the caused tooth substance-loss (thickness) as well as the attachment of PDL fibroblasts were evaluated and statistically analyzed by means of ANOVA with Post-Hoc LSD. Results After 5 treatments, bacterial reduction in biofilms was highest when applying EAP-CHX (4 log10). The lowest reduction was found after CUR (2 log10). Additionally, substance-loss was the highest when using CUR (128±40 µm) in comparison with US (14±12 µm), EAP (6±7 µm) and EAP-CHX (11±10) µm). Surface was roughened when using CUR and US. Surfaces exposed to US and to EAP attracted the highest numbers of PDL fibroblasts. Conclusion The established biofilm model simulating a periodontal pocket combined with interchangeable placements of test specimens with multi-species biofilms enables the evaluation of different non-surgical treatment modalities on biofilm removal and surface alterations. Compared to hand instrumentation the application of ultrasonication and of air

  13. Biofilm Development

    DEFF Research Database (Denmark)

    Tolker-Nielsen, Tim

    2015-01-01

    During the past decade we have gained much knowledge about the molecular mechanisms that are involved in initiation and termination of biofilm formation. In many bacteria, these processes appear to occur in response to specific environmental cues and result in, respectively, induction or terminat......During the past decade we have gained much knowledge about the molecular mechanisms that are involved in initiation and termination of biofilm formation. In many bacteria, these processes appear to occur in response to specific environmental cues and result in, respectively, induction...... or termination of biofilm matrix production via the second messenger molecule c-di-GMP. In between initiation and termination of biofilm formation we have defined specific biofilm stages, but the currently available evidence suggests that these transitions are mainly governed by adaptive responses......, and not by specific genetic programs. It appears that biofilm formation can occur through multiple pathways and that the spatial structure of the biofilms is species dependent as well as dependent on environmental conditions. Bacterial subpopulations, e.g., motile and nonmotile subpopulations, can develop...

  14. Chlorhexidine with or without alcohol against biofilm formation: efficacy, adverse events and taste preference

    Directory of Open Access Journals (Sweden)

    Gabriela Otero dos SANTOS

    2017-05-01

    Full Text Available Abstract In recent years, different chlorhexidine formulations have been tested, including an alcohol-free alternative, but the effect of this solution on early biofilm formation is not clear. A crossover, randomized, double-blind clinical trial was conducted to evaluate the effect of two chlorhexidine solutions against supra- and subgingival biofilm formation (NCT#02656251. Thirty-five participants were randomized and asked to rinse twice daily with 15 ml of an alcohol-containing 0.12% chlorhexidine solution, an alcohol-free 0.12% chlorhexidine solution, or placebo. The study was conducted in three experimental periods of 4 days each, with a 10-day washout between the periods. All the experimental periods followed the same protocol, except that the solutions were switched. Biofilm distribution was evaluated every 24 hours by the Plaque-Free Zone Index, during 96 hours. Adverse events were self-reported and sensory evaluation was performed using a hedonic scale. Compared to the placebo, the chlorhexidine solutions resulted in a significantly higher number of surfaces free of plaque over 96 hours (p < 0.01, and were able to prevent subgingival biofilm formation (p < 0.01. The alcohol-free chlorhexidine solution was associated with a lower incidence of adverse events, compared with alcohol-containing chlorhexidine (p < 0.05; it also received better sensory evaluation and acceptance by trial participants, compared with the alcohol-containing chlorhexidine (p = 0.007, and had a similar inhibitory effect on the formation of supra- and subgingival biofilms.

  15. Roles of oral bacteria in cardiovascular diseases--from molecular mechanisms to clinical cases: Treatment of periodontal disease regarded as biofilm infection: systemic administration of azithromycin.

    Science.gov (United States)

    Wang, Pao-Li

    2010-01-01

    Periodontal disease as a biofilm infectious disease is considered. Periodontal disease-associated bacteria formed biofilm in periodontal pockets or on the surface of cementum. Planktonic bacteria from biofilm invade into periodontal tissues and lead to inflammation and destruction of tissues directly and indirectly by eliciting the host defense mechanism. Supragingival dental plaques (biofilm) are easily removed by professional mechanical tooth cleaning, while subgingival dental plaques and bacteria invading into periodontal tissues are difficult to remove. Therefore, the development of a method for periodontal disease based on the concept that regards periodontal disease as a biofilm infectious disease is needed. Hereby, I report the effect of antibiotics on an in vitro biofilm model of periodontal disease and the systemic administration of azithromycin for early-onset (aggressive) periodontitis like a treatment resistant periodontitis.

  16. Subgingival Microbial Communities in Leukocyte Adhesion Deficiency and Their Relationship with Local Immunopathology

    Science.gov (United States)

    Moutsopoulos, Niki M.; Abusleme, Loreto; Greenwell-Wild, Teresa; Dutzan, Nicolas; Paster, Bruce J.; Munson, Peter J.; Fine, Daniel H.; Uzel, Gulbu; Holland, Steven M.

    2015-01-01

    Leukocyte Adhesion Deficiency I (LAD-I) is a primary immunodeficiency caused by single gene mutations in the CD18 subunit of β2 integrins which result in defective transmigration of neutrophils into the tissues. Affected patients suffer from recurrent life threatening infections and severe oral disease (periodontitis). Microbial communities in the local environment (subgingival plaque) are thought to be the triggers for inflammatory periodontitis, yet little is known regarding the microbial communities associated with LAD-I periodontitis. Here we present the first comprehensive characterization of the subgingival communities in LAD-I, using a 16S rRNA gene-based microarray, and investigate the relationship of this tooth adherent microbiome to the local immunopathology of periodontitis. We show that the LAD subgingival microbiome is distinct from that of health and Localized Aggressive Periodontitits. Select periodontitis-associated species in the LAD microbiome included Parvimonas micra, Porphyromonas endodontalis, Eubacterium brachy and Treponema species. Pseudomonas aeruginosa, a bacterium not typically found in subgingival plaque is detected in LAD-I. We suggest that microbial products from LAD-associated communities may have a role in stimulating the local inflammatory response. We demonstrate that bacterial LPS translocates into the lesions of LAD-periodontitis potentially triggering immunopathology. We also show in in vitro assays with human macrophages and in vivo in animal models that microbial products from LAD-associated subgingival plaque trigger IL-23-related immune responses, which have been shown to dominate in patient lesions. In conclusion, our current study characterizes the subgingival microbial communities in LAD-periodontitis and supports their role as triggers of disease pathogenesis. PMID:25741691

  17. Efecto del tratamiento periodontal sobre la microbiota subgingival en pacientes con preeclampsia

    OpenAIRE

    Adriana Jaramillo; Roger Arce; Adolfo Contreras; Julián A. Herrera

    2012-01-01

    Introducción. Pocos estudios han descrito la microbiota subgingival en mujeres embarazadas con preeclampsia leve. Objetivo. Identificar cambios periodontales y de la microbiota subgingival en mujeres embarazadas con preeclampsia, después del tratamiento periodontal. Materiales y métodos. En un análisis secundario de un ensayo clínico de asignación aleatoria, se estudiaron 57 pacientes con preeclampsia en el Hospital Universitario del Valle de Cali. Se asignaron al azar 31 al grupo de ...

  18. Dual lifestyle of Porphyromonas gingivalis in biofilm and gingival cells.

    Science.gov (United States)

    Sakanaka, Akito; Takeuchi, Hiroki; Kuboniwa, Masae; Amano, Atsuo

    2016-05-01

    Porphyromonas gingivalis is deeply involved in the pathogenesis of marginal periodontitis, and recent findings have consolidated its role as an important and unique pathogen. This bacterium has a unique dual lifestyle in periodontal sites including subgingival dental plaque (biofilm) and gingival cells, as it has been clearly shown that P. gingivalis is able to exert virulence using completely different tactics in each environment. Inter-bacterial cross-feeding enhances the virulence of periodontal microflora, and such metabolic and adhesive interplay creates a supportive environment for P. gingivalis and other species. Human oral epithelial cells harbor a large intracellular bacterial load, resembling the polymicrobial nature of periodontal biofilm. P. gingivalis can enter gingival epithelial cells and pass through the epithelial barrier into deeper tissues. Subsequently, from its intracellular position, the pathogen exploits cellular recycling pathways to exit invaded cells, by which it is able to control its population in infected tissues, allowing for persistent infection in gingival tissues. Here, we outline the dual lifestyle of P. gingivalis in subgingival areas and its effects on the pathogenesis of periodontitis. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. Complex Intratissue Microbiota Forms Biofilms in Periodontal Lesions.

    Science.gov (United States)

    Baek, K; Ji, S; Choi, Y

    2018-02-01

    Periodontitis is caused by dysbiotic subgingival bacterial communities that may lead to increased bacterial invasion into gingival tissues. Although shifts in community structures associated with transition from health to periodontitis have been well characterized, the nature of bacteria present within the gingival tissue of periodontal lesions is not known. To characterize microbiota within tissues of periodontal lesions and compare them with plaque microbiota, gingival tissues and subgingival plaques were obtained from 7 patients with chronic periodontitis. A sequencing analysis of the 16S rRNA gene revealed that species richness and diversity were not significantly different between the 2 groups. However, intersubject variability of intratissue communities was smaller than that of plaque communities. In addition, when compared with the plaque communities, intratissue communities were characterized by decreased abundance of Firmicutes and increased abundance of Fusobacteria and Chloroflexi. In particular, Fusobacterium nucleatum and Porphyromonas gingivalis were highly enriched within the tissue, composing 15% to 40% of the total bacteria. Furthermore, biofilms, as visualized by alcian blue staining and atomic force microscopy, were observed within the tissue where the degradation of connective tissue fibers was prominent. In conclusion, very complex bacterial communities exist in the form of biofilms within the gingival tissue of periodontal lesions, which potentially serve as a reservoir for persistent infection. This novel finding may prompt new research on therapeutic strategies to treat periodontitis.

  20. The Effect of Apically Repositioned Flap Surgery on Clinical Parameters and the Composition of the Subgingival Microbiota: 12-Month Data

    Science.gov (United States)

    Levy, Rustin M.; Giannobile, William V.; Feres, Magda; Haffajee, Anne D.; Smith, Claire; Socransky, Sigmund S.

    2008-01-01

    The purpose of this investigation was to examine the clinical and microbiologic effects of apically repositioned flap surgery. Eighteen patients with chronic periodontitis received initial preparation (IP) including scaling and root planing, followed at 3 months by apically repositioned flap surgery at sites with pocket depth > 4 mm. Subjects were monitored clinically and microbiologically at baseline, 3 months after IP, and at 3, 6, 9, and 12 months postsurgery. Clinical assessments of plaque accumulation, gingival redness, suppuration, bleeding on probing, pocket depth, and attachment level were made at six sites per tooth. Subgingival plaque samples were taken from the mesial aspect of each tooth, and the presence and levels of 40 subgingival taxa were determined using checkerboard DNA-DNA hybridization. Significant reductions were seen in mean pocket depth and percentage of sites exhibiting gingival redness and bleeding on probing in both sites that received IP only and in sites receiving IP followed by surgery. Mean attachment level increased significantly for both sets of sites, but the increase was greater at the surgically treated sites. The total DNA probe counts were significantly reduced at sites in both treatment groups. At surgically treated sites, 19 of 40 taxa were significantly reduced posttherapy. At sites receiving IP only, 16 species were significantly reduced over time. While there were some reductions in mean counts after IP in this site group, the major reductions occurred after the surgical phase in these patients, even though these particular sites did not receive surgical therapy. The reduction in pocket depth by surgical means and the associated decrease in reservoirs of periodontal pathogens may be important in achieving sustained periodontal stability. PMID:12186343

  1. Chlorhexidine with or without alcohol against biofilm formation: efficacy, adverse events and taste preference.

    Science.gov (United States)

    Santos, Gabriela Otero Dos; Milanesi, Fernanda Carpes; Greggianin, Bruna Frizon; Fernandes, Marilene Issa; Oppermann, Rui Vicente; Weidlich, Patricia

    2017-05-04

    In recent years, different chlorhexidine formulations have been tested, including an alcohol-free alternative, but the effect of this solution on early biofilm formation is not clear. A crossover, randomized, double-blind clinical trial was conducted to evaluate the effect of two chlorhexidine solutions against supra- and subgingival biofilm formation (NCT#02656251). Thirty-five participants were randomized and asked to rinse twice daily with 15 ml of an alcohol-containing 0.12% chlorhexidine solution, an alcohol-free 0.12% chlorhexidine solution, or placebo. The study was conducted in three experimental periods of 4 days each, with a 10-day washout between the periods. All the experimental periods followed the same protocol, except that the solutions were switched. Biofilm distribution was evaluated every 24 hours by the Plaque-Free Zone Index, during 96 hours. Adverse events were self-reported and sensory evaluation was performed using a hedonic scale. Compared to the placebo, the chlorhexidine solutions resulted in a significantly higher number of surfaces free of plaque over 96 hours (p chlorhexidine solution was associated with a lower incidence of adverse events, compared with alcohol-containing chlorhexidine (p chlorhexidine (p = 0.007), and had a similar inhibitory effect on the formation of supra- and subgingival biofilms.

  2. Wound biofilms: lessons learned from oral biofilms

    Science.gov (United States)

    Mancl, Kimberly A.; Kirsner, Robert S.; Ajdic, Dragana

    2013-01-01

    Biofilms play an important role in the development and pathogenesis of many chronic infections. Oral biofilms, more commonly known as dental plaque,are a primary cause of oral diseases including caries, gingivitis and periodontitis. Oral biofilms are commonly studied as model biofilm systems as they are easily accessible, thus biofilm research in oral diseases is advanced with details of biofilm formation and bacterial interactions being well-elucidated. In contrast, wound research has relatively recently directed attentionto the role biofilms have in chronic wounds. This review discusses the biofilms in periodontal disease and chronic wounds with comparisons focusing on biofilm detection, biofilm formation, the immune response to biofilms, bacterial interaction and quorum sensing. Current treatment modalities used by both fields as well as future therapies are also discussed. PMID:23551419

  3. Evaluation of the Effect of Different Growth Media and Temperature on the Suitability of Biofilm Formation by Enterobacter cloacae Strains Isolated from Food Samples in South Africa

    Directory of Open Access Journals (Sweden)

    Mirriam E. Nyenje

    2013-08-01

    Full Text Available This study evaluated the effects of growth medium, temperature, and incubation time on biofilm formation by Enterobacter cloacae strains. The ability to adhere to a surface was demonstrated using a microtiter plate adherence assay whereas the role of cell surface properties in biofilm formation was assessed using the coaggregation and autoaggregation assays. The architecture of the biofilms was examined under scanning electron microscope (SEM. All the strains adhered to the well of the microtiter plate when incubated for 48 h, irrespective of the growth medium and incubation temperature. It was also noted that 90% and 73% of strains prepared from nutrient broth and cultured in brain heart infusion (BHI broth and tryptic soy broth (TSB, respectively, were able to form biofilms, in contrast to 73% and 60% strains from nutrient agar and cultured in BHI and TSB respectively grown under similar conditions. However, no statistically significant difference was observed when the two methods were compared. The coaggregation index ranged from 12% to 74%, with the best coaggregate activity observed when partnered with Streptococcus pyogenes (54%–74%. The study indicates the suitability of BHI and TSB medium for the cultivation of E. cloacae biofilms, however, temperature and incubation time significantly affect biofilm formation by these bacteria.

  4. Evaluation of the effect of different growth media and temperature on the suitability of biofilm formation by Enterobacter cloacae strains isolated from food samples in South Africa.

    Science.gov (United States)

    Nyenje, Mirriam E; Green, Ezekiel; Ndip, Roland N

    2013-08-09

    This study evaluated the effects of growth medium, temperature, and incubation time on biofilm formation by Enterobacter cloacae strains. The ability to adhere to a surface was demonstrated using a microtiter plate adherence assay whereas the role of cell surface properties in biofilm formation was assessed using the coaggregation and autoaggregation assays. The architecture of the biofilms was examined under scanning electron microscope (SEM). All the strains adhered to the well of the microtiter plate when incubated for 48 h, irrespective of the growth medium and incubation temperature. It was also noted that 90% and 73% of strains prepared from nutrient broth and cultured in brain heart infusion (BHI) broth and tryptic soy broth (TSB), respectively, were able to form biofilms, in contrast to 73% and 60% strains from nutrient agar and cultured in BHI and TSB respectively grown under similar conditions. However, no statistically significant difference was observed when the two methods were compared. The coaggregation index ranged from 12% to 74%, with the best coaggregate activity observed when partnered with Streptococcus pyogenes (54%-74%). The study indicates the suitability of BHI and TSB medium for the cultivation of E. cloacae biofilms, however, temperature and incubation time significantly affect biofilm formation by these bacteria.

  5. Quantification of diatoms in biofilms: Standardisation of methods

    Digital Repository Service at National Institute of Oceanography (India)

    Patil, J.S.; Anil, A.C.

    of the difficulty in sampling and enumeration. Scraping or brushing are the traditional methods used for removal of diatoms from biofilms developed on solid substrata. The method of removal is the most critical step in enumerating the biofilm diatom community...

  6. Managing sub-gingival fracture by multi-disciplinary approach: Endodontics-forced orthodontic extrusion and prosthetic rehabilitation

    Directory of Open Access Journals (Sweden)

    Rakesh Mittal

    2013-01-01

    Full Text Available Traumatized anterior teeth with sub-gingival crown fractures are a challenge to treat. The management of sub-gingival fractures includes exposing the cervical margin followed by appropriate coronal restoration. The treatment modalities, which involve exposing the cervical margin, are surgical crown lengthening and orthodontic extrusion. This paper reports a case of fractured maxillary anterior tooth at the sub-gingival level that was managed by forced orthodontic extrusion after endodontic treatment followed by esthetic rehabilitation, a much forgotten technique not utilized routinely yet conservative and cost-effective.

  7. Comparison of visual-tactile, radiographic, and histologic diagnoses of subgingival crown margin caries- an in vitro study.

    Science.gov (United States)

    Wittneben, Julia-Gabriela; Zöllner, Axel; Wright, Axel F; Weber, Hans-Peter

    2009-01-01

    The purpose of this study was to investigate the accuracy of diagnosing interproximal subgingival caries at crown margins. A total of 32 subgingival interproximal crown margin areas were examined by 10 clinicians (n = 320) using conventional diagnostic methods on extracted, crowned teeth mounted in a specially designed cast. Crown margins were located 1.5 mm below the level of the artificial gingiva. Clinical and radiographic diagnoses were compared to the histopathologic findings for each site. Both visual-tactile and radiographic evaluations revealed a weak diagnostic accuracy for interproximal subgingival crown margin caries.

  8. Bacterial biofilms. Bacteria Quorum sensing in biofilms

    Directory of Open Access Journals (Sweden)

    E. S. Vorobey

    2012-03-01

    Full Text Available Data on biofilms, their structure and properties, peculiarities of formation and interaction between microorganisms in the film are presented. Information on discovery and study of biofilms, importance of biofilms in the medical and clinical microbiology are offered. The data allow to interpret biofilm as a form of existence of human normal microflora. For the exchange of information within the biofilm between the individual cells of the same or different species bacteria use the signal molecules of the Quorum sensing system. Coordination of bacterial cells activity in the biofilms gives them significant advantages: in the biofilms bacteria are protected from the influence of the host protective factors and the antibacterial drugs.

  9. Biofilm Risks

    DEFF Research Database (Denmark)

    Wirtanen, Gun Linnea; Salo, Satu

    2016-01-01

    in food factories. In the prevention of biofilm formation microbial control in process lines should both limit the number of microbes on surfaces and reduce microbial activity in the process. Thus the hygienic design of process equipment and process lines is important in improving the process hygiene...

  10. Investigation of the Effect of Type 2 Diabetes Mellitus on Subgingival Plaque Microbiota by High-Throughput 16S rDNA Pyrosequencing

    Science.gov (United States)

    Munro, Daniel; Zhu, Chunxia; Gao, Xiang; Zhang, Qi; Dong, Qunfeng

    2013-01-01

    Diabetes mellitus is a major risk factor for chronic periodontitis. We investigated the effects of type 2 diabetes on the subgingival plaque bacterial composition by applying culture-independent 16S rDNA sequencing to periodontal bacteria isolated from four groups of volunteers: non-diabetic subjects without periodontitis, non-diabetic subjects with periodontitis, type 2 diabetic patients without periodontitis, and type 2 diabetic patients with periodontitis. A total of 71,373 high-quality sequences were produced from the V1-V3 region of 16S rDNA genes by 454 pyrosequencing. Those 16S rDNA sequences were classified into 16 phyla, 27 classes, 48 orders, 85 families, 126 genera, and 1141 species-level OTUs. Comparing periodontally healthy samples with periodontitis samples identified 20 health-associated and 15 periodontitis-associated OTUs. In the subjects with healthy periodontium, the abundances of three genera (Prevotella, Pseudomonas, and Tannerella) and nine OTUs were significantly different between diabetic patients and their non-diabetic counterparts. In the subjects carrying periodontitis, the abundances of three phyla (Actinobacteria, Proteobacteria, and Bacteriodetes), two genera (Actinomyces and Aggregatibacter), and six OTUs were also significantly different between diabetics and non-diabetics. Our results show that type 2 diabetes mellitus could alter the bacterial composition in the subgingival plaque. PMID:23613868

  11. Presence of Helicobacter pylori in subgingival plaque of periodontitis patients with and without dyspepsia, detected by polymerase chain reaction and culture.

    Science.gov (United States)

    Agarwal, Sangita; Jithendra, K D

    2012-07-01

    Helicobacter pylori is an important gastrointestinal pathogen that is strongly associated with gastritis as well as peptic ulcer disease. Antimicrobial therapy frequently fails to cure H. pylori infection, which suggests there may be sanctuary sites where the organism resides. This study was aimed to assess the role of oral cavity as a reservoir of H. pylori by evaluating the occurrence of the organism in subgingival plaque of dyspeptic patients by polymerase chain reaction as well as culture. Thirty chronic periodontitis patients whose biopsy specimens were found to be H. pylori positive with rapid urease test and histopathologic examination were considered as cases and 20 chronic periodontitis patients who never had any symptoms of gastritis or peptic ulcer were taken as controls. Subgingival plaque samples were collected and sent to microbiological laboratory for detection of H. pylori by 16S rRNA based polymerase chain reaction as well as culture. 60% of the samples were found to be positive with polymerase chain reaction in the case group when compared to 15% in the controls. Also, 30% of the cases were found to be positive with culture compared to none in controls. A higher frequency of detection of H. pylori in those patients with positive antral biopsy report was seen. Also, polymerase chain reaction was found to be more sensitive than culture for detection. Thus, we conclude that detection of H. pylori in dental plaque of dyspeptic patients cannot be neglected and might represent a risk factor for recolonization of stomach after systemic eradication therapy.

  12. Comparative gene expression analysis of Porphyromonas gingivalis ATCC 33277 in planktonic and biofilms states.

    Science.gov (United States)

    Romero-Lastra, P; Sánchez, M C; Ribeiro-Vidal, H; Llama-Palacios, A; Figuero, E; Herrera, D; Sanz, M

    2017-01-01

    Porphyromonas gingivalis is a keystone pathogen in the onset and progression of periodontitis. Its pathogenicity has been related to its presence and survival within the subgingival biofilm. The aim of the present study was to compare the genome-wide transcription activities of P. gingivalis in biofilm and in planktonic growth, using microarray technology. P. gingivalis ATCC 33277 was incubated in multi-well culture plates at 37°C for 96 hours under anaerobic conditions using an in vitro static model to develop both the planktonic and biofilm states (the latter over sterile ceramic calcium hydroxyapatite discs). The biofilm development was monitored by Confocal Laser Scanning Microscopy (CLSM) and Scanning Electron Microscopy (SEM). After incubation, the bacterial cells were harvested and total RNA was extracted and purified. Three biological replicates for each cell state were independently hybridized for transcriptomic comparisons. A linear model was used for determining differentially expressed genes and reverse transcription quantitative polymerase chain reaction (RT-qPCR) was used to confirm differential expression. The filtering criteria of ≥ ±2 change in gene expression and significance p-values of gingivalis growing in biofilm compared to planktonic. The 54 up-regulated genes in biofilm growth were mainly related to cell envelope, transport, and binding or outer membranes proteins. Thirty-eight showed decreased expression, mainly genes related to transposases or oxidative stress. The adaptive response of P. gingivalis in biofilm growth demonstrated a differential gene expression.

  13. Staphylococcus aureus dry-surface biofilms are more resistant to heat treatment than traditional hydrated biofilms.

    Science.gov (United States)

    Almatroudi, A; Tahir, S; Hu, H; Chowdhury, D; Gosbell, I B; Jensen, S O; Whiteley, G S; Deva, A K; Glasbey, T; Vickery, K

    2018-02-01

    The importance of biofilms to clinical practice is being increasingly realized. Biofilm tolerance to antibiotics is well described but limited work has been conducted on the efficacy of heat disinfection and sterilization against biofilms. To test the susceptibility of planktonic, hydrated biofilm and dry-surface biofilm forms of Staphylococcus aureus, to dry-heat and wet-heat treatments. S. aureus was grown as both hydrated biofilm and dry-surface biofilm in the CDC biofilm generator. Biofilm was subjected to a range of temperatures in a hot-air oven (dry heat), water bath or autoclave (wet heat). Dry-surface biofilms remained culture positive even when treated with the harshest dry-heat condition of 100°C for 60min. Following autoclaving samples were culture negative but 62-74% of bacteria in dry-surface biofilms remained alive as demonstrated by live/dead staining and confocal microscopy. Dry-surface biofilms subjected to autoclaving at 121°C for up to 30min recovered and released planktonic cells. Recovery did not occur following autoclaving for longer or at 134°C, at least during the time-period tested. Hydrated biofilm recovered following dry-heat treatment up to 100°C for 10min but failed to recover following autoclaving despite the presence of 43-60% live cells as demonstrated by live/dead staining. S. aureus dry-surface biofilms are less susceptible to killing by dry heat and steam autoclaving than hydrated biofilms, which are less susceptible to heat treatment than planktonic suspensions. Copyright © 2017 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.

  14. Solid-state NMR for bacterial biofilms

    Science.gov (United States)

    Reichhardt, Courtney; Cegelski, Lynette

    2014-04-01

    Bacteria associate with surfaces and one another by elaborating an extracellular matrix to encapsulate cells, creating communities termed biofilms. Biofilms are beneficial in some ecological niches, but also contribute to the pathogenesis of serious and chronic infectious diseases. New approaches and quantitative measurements are needed to define the composition and architecture of bacterial biofilms to help drive the development of strategies to interfere with biofilm assembly. Solid-state nuclear magnetic resonance (NMR) is uniquely suited to the examination of insoluble and complex macromolecular and whole-cell systems. This article highlights three examples that implement solid-state NMR to deliver insights into bacterial biofilm composition and changes in cell-wall composition as cells transition to the biofilm lifestyle. Most recently, solid-state NMR measurements provided a total accounting of the protein and polysaccharide components in the extracellular matrix of an Escherichia coli biofilm and transformed our qualitative descriptions of matrix composition into chemical parameters that permit quantitative comparisons among samples. We present additional data for whole biofilm samples (cells plus the extracellular matrix) that complement matrix-only analyses. The study of bacterial biofilms by solid-state NMR is an exciting avenue ripe with many opportunities and we close the article by articulating some outstanding questions and future directions in this area.

  15. AFM Structural Characterization of Drinking Water Biofilm ...

    Science.gov (United States)

    Due to the complexity of mixed culture drinking water biofilm, direct visual observation under in situ conditions has been challenging. In this study, atomic force microscopy (AFM) revealed the three dimensional morphology and arrangement of drinking water relevant biofilm in air and aqueous solution. Operating parameters were optimized to improve imaging of structural details for a mature biofilm in liquid. By using a soft cantilever (0.03 N/m) and slow scan rate (0.5 Hz), biofilm and individual bacterial cell’s structural topography were resolved and continuously imaged in liquid without loss of spatial resolution or sample damage. The developed methodology will allow future in situ investigations to temporally monitor mixed culture drinking water biofilm structural changes during disinfection treatments. Due to the complexity of mixed culture drinking water biofilm, direct visual observation under in situ conditions has been challenging. In this study, atomic force microscopy (AFM) revealed the three dimensional morphology and arrangement of drinking water relevant biofilm in air and aqueous solution. Operating parameters were optimized to improve imaging of structural details for a mature biofilm in liquid. By using a soft cantilever (0.03 N/m) and slow scan rate (0.5 Hz), biofilm and individual bacterial cell’s structural topography were resolved and continuously imaged in liquid without loss of spatial resolution or sample damage. The developed methodo

  16. Subgingival microbiota in health compared to periodontitis and the influence of smoking.

    OpenAIRE

    Camelo-Castillo, A. J.; Mira, A.; Pico, A.; Nibali, L.; Henderson, B.; Donos, N.; Tomás, I.

    2015-01-01

    The etiology of periodontitis has traditionally been associated to a consortium of three bacterial species-the so-called "red-complex" of periodontal disease-which has been the target for most diagnostic and therapeutic strategies. However, other species have also been found to correlate with disease severity. In addition, the influence of smoking on periodontal microbiota is poorly understood. In the current manuscript, the composition of the subgingival microbiota in healthy individuals vs....

  17. Effect of smoking on subgingival microflora of patients with periodontitis in Japan

    OpenAIRE

    Kubota, Michiya; Tanno-Nakanishi, Mariko; Yamada, Satoru; Okuda, Katsuji; Ishihara, Kazuyuki

    2011-01-01

    Abstract Background Smoking is a risk factor for periodontitis. To clarify the contribution of smoking to periodontitis, it is essential to assess the relationship between smoking and the subgingival microflora. The aim of this study was to gain an insight into the influence of smoking on the microflora of Japanese patients with periodontitis. Methods Sixty-seven Japanese patients with chronic periodontitis (19 to 83 years old, 23 women and 44 men) were enrolled in the present study. They con...

  18. Oral cavity anaerobic pathogens in biofilm formation on voice prostheses

    NARCIS (Netherlands)

    Bertl, Kristina; Zijnge, Vincent; Zatorska, Beata; Leonhard, Matthias; Schneider-Stickler, Berit; Harmsen, Hermie J. M.

    BACKGROUND: A polymerase chain reaction (PCR)-based method has been used to identify oral anaerobic pathogens in biofilms on voice prostheses. The purpose of the present study was to determine the location of those pathogens inside the biofilms. METHODS: Biofilms of 15 voice prostheses were sampled

  19. Tracking of Actinobacillus actinomycetemcomitans in subgingival plaque of aggressive periodontitis patients

    Directory of Open Access Journals (Sweden)

    Supriya Kheur

    2010-01-01

    Full Text Available Background: Actinobacillus actinomycetemcomitans is thought to be one of the etiological agents in aggressive periodontitis as well as indicated in various systemic diseases. Objective: To evaluate the prevalence of A. actinomycetemcomitans in the subgingival plaque of aggressive periodontitis patients. Study Design: Initially, under the selective growth conditions, the isolates were picked from the plaques and their identification was confirmed by polymerase chain reaction using primers specific for A. actinomycetemcomitans subgingival plaque of 15 patients diagnosed clinically and on radiographic criteria as aggressive periodontitis was inoculated on the Tryptic Soy agar with Bacitracin and Vancomycin culture media for 3-5 days under microaerophilic conditions. The positive colonies were selected based on biochemical tests for further analysis using reported primers for A. actinomycetemcomitans. Results: The results showed that 66.67% of aggressive periodontitis patients and 6.67% of control group of normal patients showed evidence of presence of A. actinomycetemcomitans in the subgingival microflora. Conclusion: This is the first study of its kind in an Indian population whereby almost all aggressive periodontitis patients showed evidence of A. actinomycetemcomitans.

  20. Representation of microorganisms of subgingival plaque at different degrees of periodontium tissue inflamation and destruction

    Directory of Open Access Journals (Sweden)

    Staletović Danijela

    2014-01-01

    Full Text Available Parodontopathy is an inflammatory reaction to gram negative anaerobic bacterial infectious agents that attacks the supporting dental apparatus including gingiva, periodontal ligament, cement and alveolar bone. The aim of the survey was to identify quantitative qualitative structure of microorganisms of subgingival plaque in patients suffering from chronic and aggressive parodontopathy using the PCR method, and then evaluate the correlation of different degrees of inflammation and destruction of periodontium tissue with the presence and concentration of these microorganisms. The survey involved 70 patients, 16 to 65 years old. The identification of microorganisms in subgingival plaque was set by the PCR method (Polymerase Chain Reaction. Towards diagnosing and defining the destruction degree of periodontal tissue, standard epidemiological criteria were used: plaque index (Silness-Löe, gingival index (Löe-Silness, SBI index (Mühleman-Son and PDDZ. The presence of periodontal pathogens in subgingival plaque showed the statistical link with clinical parameters of the severeness of parodontopathy and gingival inflammation. The test result of Porphyromonas gingivalis and Actinobacillus actinomycetemcomitans statistically was significantly more frequent in patients with medium and severe type of parodontopathy compared to the average depth of periodontal pockets. The detection of P.g. and A.a. statistically was significantly more frequent in persons with mild and intensive gingival inflammation.

  1. Drug resistance of bacterial dental biofilm and the potential use of natural compounds as alternative for prevention and treatment.

    Science.gov (United States)

    Kouidhi, Bochra; Al Qurashi, Yasir Mohammed A; Chaieb, Kamel

    2015-03-01

    Oral diseases, such as dental caries and periodontal disease are directly linked with the ability of bacteria to form biofilm. The development of dental caries involves acidogenic and aciduric Gram-positive bacteria colonizing the supragingival biofilm (Streptococcus, Lactobacillus and Actinomycetes). Periodontal diseases have been linked to anaerobic Gram-negative bacteria forming a subgingival plaque (Porphyromonas gingivalis, Actinobacillus, Prevotella and Fusobacterium). Cells embedded in biofilm are up to 1000-fold more resistant to antibiotics compared to their planctonic ones. Several mechanisms have been proposed to explain biofilms drug resistance. Given the increased bacterial resistance to antibiotics currently used in dentistry, a great importance is given to natural compounds for the prevention of oral bacterial growth, adhesion and colonization. Over the past decade, interest in drugs derived from medicinal plants has markedly increased. It has been well documented that medicinal plants and natural compounds confer considerable antibacterial activity against various microorganisms including cariogenic and periodontal pathogens. This paper provides a review of the literature focusing on the studies on (i) biofilm in the oral cavity, (ii) drug resistance of bacterial biofilm and (iii) the potential use of plant extracts, essential oils and natural compounds as biofilm preventive agents in dentistry, involving their origin and their mechanism of biofilm inhibition. Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. Bacterial and archael 16S rRNA sequences and taxonomic summary tables for biofilm samples from the bio-reactors

    Data.gov (United States)

    U.S. Environmental Protection Agency — A biofilm anode acclimated with acetate, acetate+methane, and methane growth media for over three years produced a steady current density of 1.6-2.3 mA/m^2 in a...

  3. Efficacy of NVC-422 against Staphylococcus aureus biofilms in a sheep biofilm model of sinusitis.

    Science.gov (United States)

    Singhal, Deepti; Jekle, Andreas; Debabov, Dmitri; Wang, Lu; Khosrovi, Bez; Anderson, Mark; Foreman, Andrew; Wormald, Peter-John

    2012-01-01

    Bacterial biofilms are a major obstacle in management of recalcitrant chronic rhinosinusitis. NVC-422 is a potent, fast-acting, broad-spectrum, nonantibiotic, antimicrobial with a new mechanism of action effective against biofilm bacteria in in vitro conditions. The aim of this study was to investigate the safety and efficacy of NVC-422 as local antibiofilm treatment in a sheep model of rhinosinusitis. After accessing and occluding frontal sinus ostia in 24 merino sheep via staged endoscopic procedures, S. aureus clinical isolate was instilled in frontal sinuses. Following biofilm formation, ostial obstruction was removed and sinuses irrigated with 0.1% and 0.5% NVC-422 in 5 mM acetate isotonic saline at pH 4.0. Sheep were monitored for adverse effects and euthanized 24 hours after treatment. Frontal sinuses were assessed for infection and changes in mucosa after the treatment. S. aureus biofilms were identified with Baclight-confocal scanning microscopy protocol and the biofilm biomass assayed by applying the COMSTAT2 program to recorded image stacks. After 2 irrigations with 0.1% NVC-422, S. aureus biofilm biomass was reduced when compared to control sinuses (p = 0.0001), though this effect was variable in samples. NVC-422 0.5% solution irrigations reduced biofilm even more significantly and consistently over all samples (p biofilm biomass (p biofilms, with dose-dependent efficacy in this animal model of biofilm-associated sinusitis. Copyright © 2012 American Rhinologic Society-American Academy of Otolaryngic Allergy, LLC.

  4. Characterization of specimens obtained by different sampling methods for evaluation of periodontal bacteria.

    Science.gov (United States)

    Okada, Ayako; Sogabe, Kaoru; Takeuchi, Hiroaki; Okamoto, Masaaki; Nomura, Yoshiaki; Hanada, Nobuhiro

    2017-11-17

    Quantitative analysis of periodontal bacteria is considered useful for clinical diagnosis, evaluation and assessment of the risk of periodontal disease. The purpose of this study was to compare the effectiveness of sampling of saliva, supragingival and subgingival plaque for evaluation of periodontal bacteria. From each of 12 subjects, i) subgingival plaque was collected from the deepest pocket using a sterile paper point, ii) stimulated whole saliva was collected after chewing gum, and iii) supragingival plaque was collected using a tooth brush. These samples were sent to the medical examination laboratory for quantitative analysis of the counts of three periodontal bacterial species: Porphyromonas gingivalis, Treponema denticola, and Tannerella forsythia. The proportions of these bacteria in subgingival plaque were higher than those in saliva or supragingival plaque, but lower in subgingival plaque than in saliva or supragingival plaque. In several cases, periodontal bacteria were below the levels of detection in subgingival plaque. We concluded that samples taken from subgingival plaque may be more useful for evaluating the proportion of periodontal bacteria in deep pockets than is the case for other samples. Therefore, for evaluation of periodontal bacteria, clinicians should consider the characteristics of the specimens obtained using different sampling methods.

  5. Confocal Raman microscopy for identification of bacterial species in biofilms

    Science.gov (United States)

    Beier, Brooke D.; Quivey, Robert G.; Berger, Andrew J.

    2011-03-01

    Implemented through a confocal microscope, Raman spectroscopy has been used to distinguish between biofilm samples of two common oral bacteria species, Streptococcus sanguinis and mutans, which are associated with healthy and cariogenic plaque, respectively. Biofilms of these species are studied as a model of dental plaque. A prediction model has been calibrated and validated using pure biofilms. This model has been used to identify the species of transferred and dehydrated samples (much like a plaque scraping) as well as hydrated biofilms in situ. Preliminary results of confocal Raman mapping of species in an intact two-species biofilm will be shown.

  6. Biodynamics of biofilm formation on nasogastric tubes in elderly patients.

    Science.gov (United States)

    Leibovitz, Arthur; Baumoehl, Yehuda; Steinberg, Doron; Segal, Refael

    2005-07-01

    We previously reported on the high propensity of pathogenic oral flora in the oropharynx of nasogastric tube-fed patients, and subsequently showed biofilm formation on the NGTs of these patients. There is a close relationship of biofilm and oropharyngeal colonization with pathogenic bacteria, aspiration pneumonia and antibiotic resistance. To investigate the time relation between the insertion of a new NGT and formation of the biofilm. We examined sequential samples on NGTs that were forcibly pulled out by the patients themselves during any of the 7 days after insertion. Scanning electron micrography and confocal laser scanning microscopy were used for biofilm detection. Biofilm was identified on 60% of the five samples of day 1 and on all the samples of the following days, by both microscopic methods. Biofilms form within a single day on most NGTs inserted for the feeding of elderly patients with dysphagia. Further research should be devoted to prevention of biofilm formation on NGTs.

  7. The Biofilm Challenge

    DEFF Research Database (Denmark)

    Alhede, Maria; Alhede, Morten

    2014-01-01

    The concept of biofilms has emerged in the clinical setting during the last decade. Infections involving biofilms have been documented in all parts of the human body, and it is currently believed that the presence of biofilm-forming bacteria is equivalent to chronic infection. A quick Pubmed search...... reveals the significance of biofilms, as evidenced by a dramatic increase in scientific publications on the topic, as well as in publications concerning wounds with biofilms, which reached 600 publications in 2013. Judged from the number of publications, it appears that biofilms play a significant role...... in wounds. However, the impact of biofilms is often debated, because infected wounds were also treated before the concept of biofilms was coined. In this short review, we will address the significance of biofilms and their role in wounds, and discuss the future tasks of the biofilm challenge....

  8. The in vivo biofilm

    DEFF Research Database (Denmark)

    Bjarnsholt, Thomas; Alhede, Maria; Alhede, Morten

    2013-01-01

    Bacteria can grow and proliferate either as single, independent cells or organized in aggregates commonly referred to as biofilms. When bacteria succeed in forming a biofilm within the human host, the infection often becomes very resistant to treatment and can develop into a chronic state. Biofilms...... have been studied for decades using various in vitro models, but it remains debatable whether such in vitro biofilms actually resemble in vivo biofilms in chronic infections. In vivo biofilms share several structural characteristics that differ from most in vitro biofilms. Additionally, the in vivo...... experimental time span and presence of host defenses differ from chronic infections and the chemical microenvironment of both in vivo and in vitro biofilms is seldom taken into account. In this review, we discuss why the current in vitro models of biofilms might be limited for describing infectious biofilms...

  9. Planktonic versus biofilm catabolic communities: importance of the biofilm for species selection and pesticide degradation.

    Science.gov (United States)

    Verhagen, Pieter; De Gelder, Leen; Hoefman, Sven; De Vos, Paul; Boon, Nico

    2011-07-01

    Chloropropham-degrading cultures were obtained from sludge and soil samples by using two different enrichment techniques: (i) planktonic enrichments in shaken liquid medium and (ii) biofilm enrichments on two types of solid matrixes (plastic chips and gravel). Denaturing gradient gel electrophoresis fingerprinting showed that planktonic and biofilm cultures had a different community composition depending on the presence and type of added solid matrix during enrichment. This was reflected in the unique chloropropham-degrading species that could be isolated from the different cultures. Planktonic and biofilm cultures also differed in chloropropham-degrading activity. With biofilm cultures, slower chloropropham removal was observed, but with less build-up of the toxic intermediate 3-chloroaniline. Disruption of the biofilm architecture resulted in degradation characteristics shifting toward those of the free suspensions, indicating the importance of a well-established biofilm structure for good performance. These results show that biofilm-mediated enrichment techniques can be used to select for pollutant-degrading microorganisms that like to proliferate in a biofilm and that cannot be isolated using conventional shaken-liquid procedures. Furthermore, the influence of the biofilm architecture on the pesticide degradation characteristics suggests that for bioaugmentation the use of biofilm catabolic communities might be a proficient alternative to using planktonic freely suspended cultures.

  10. Fungal Biofilms: Inside Out.

    Science.gov (United States)

    Lagree, Katherine; Mitchell, Aaron P

    2017-04-01

    We focus this article on turning a biofilm inside out. The "inside" of the biofilm comprises the individual biofilm-related phenotypes, their environmental drivers and genetic determinants, and the coordination of gene functions through transcriptional regulators. Investigators have viewed the inside of the biofilm through diverse approaches, and this article will attempt to capture the essence of many. The ultimate goal is to connect the inside to the "outside," which we view as biofilm structure, development, pharmacological attributes, and medical impact.

  11. Infeksi Biofilm Bakterial

    OpenAIRE

    Homenta, Heriyannis

    2016-01-01

    : Biofilm is the unity of microbial cell surface surrounded by a matrix of extracellular polymeric substances (EPS). Bacteria composing the biofilm are heterogeneous in space and time. This biofilm continues to grow influenced by internal and external processes. Moreover, biofilm can be found on the surface of medical devices, as well as in bacterial endocarditis and cystic fibrosis. Biofilm that is already formed can lead to antibiotic resistance.

  12. Biophysics of biofilm infection.

    Science.gov (United States)

    Stewart, Philip S

    2014-04-01

    This article examines a likely basis of the tenacity of biofilm infections that has received relatively little attention: the resistance of biofilms to mechanical clearance. One way that a biofilm infection persists is by withstanding the flow of fluid or other mechanical forces that work to wash or sweep microorganisms out of the body. The fundamental criterion for mechanical persistence is that the biofilm failure strength exceeds the external applied stress. Mechanical failure of the biofilm and release of planktonic microbial cells is also important in vivo because it can result in dissemination of infection. The fundamental criterion for detachment and dissemination is that the applied stress exceeds the biofilm failure strength. The apparent contradiction for a biofilm to both persist and disseminate is resolved by recognizing that biofilm material properties are inherently heterogeneous. There are also mechanical aspects to the ways that infectious biofilms evade leukocyte phagocytosis. The possibility of alternative therapies for treating biofilm infections that work by reducing biofilm cohesion could (1) allow prevailing hydrodynamic shear to remove biofilm, (2) increase the efficacy of designed interventions for removing biofilms, (3) enable phagocytic engulfment of softened biofilm aggregates, and (4) improve phagocyte mobility and access to biofilm. © 2013 Federation of European Microbiological Societies. Published by John Wiley & Sons Ltd. All rights reserved.

  13. Reproducibility of subgingival bacterial samples from patients with peri-implant mucositis

    DEFF Research Database (Denmark)

    Hallström, Hadar; Persson, G Rutger; Strömberg, Ulf

    2015-01-01

    collected with paper points and analyzed using the checkerboard DNA-DNA hybridization technique. Whole genomic probes of 74 preselected bacterial species were used. Based on the bacterial scores, Cohen's kappa coefficient was used to calculate the inter-annotator agreement for categorical data...

  14. Biofilm formation in a hot water system

    DEFF Research Database (Denmark)

    Bagh, L.K.; Albrechtsen, Hans-Jørgen; Arvin, Erik

    2002-01-01

    The biofilm formation rate was measured in situ in a hot water system in an apartment building by specially designed sampling equipment, and the net growth of the suspended bacteria was measured by incubation of water samples with the indigeneous bacteria. The biofilm formation rate reached......, in the sludge, or in the water from the distribution system was negligible. This indicated that bacterial growth took place on the inner surfaces in the hot water system and biofilm formation and detachment of bacteria could account for most of the suspended bacteria actually measured in hot water. Therefore...

  15. Subgingival air-polishing with erythritol during periodontal maintenance: randomized clinical trial of twelve months.

    Science.gov (United States)

    Müller, Nada; Moëne, Raphaël; Cancela, José A; Mombelli, Andrea

    2014-09-01

    To evaluate repeated subgingival air-polishing in residual pockets with a new erythritol powder containing 0.3% chlorhexidine. Single-centre, examiner masked, randomized clinical trial of 12 months with a two-arm, within-subject parallel design. Fifty patients in periodontal maintenance were monitored in 3-month intervals. At months 0, 3, 6 and 9, all sites presenting with a probing depth (PD) >4 mm were subject to subgingival air-polishing (test side) or ultrasonic debridement (control side). The primary endpoint was presence/absence of PD >4 mm after 12 months. Totally 6918 sites were monitored at baseline, 457 of them had a PD >4 mm (range 5-9 mm). The number of pockets >4 mm per subject, PD and bleeding on probing were significantly lower at month 12. Differences between test and control were not significant. There was a significant difference in favour of air-polishing for the perception of pain/discomfort. Differences of frequencies at >1000 and >100,000 cells/ml of six microorganisms between baseline and month 12 were not significant. At month 12, test sites were less frequently positive for Aggregatibacter actinomycetemcomitans at >1000 cells/ml than controls, and counts never exceeded 100,000 cells/ml. Repeated subgingival air-polishing reduced the number of pockets >4 mm similar to ultrasonic debridement. It was safe and induced less pain. © 2014 The Authors. Journal of Clinical Periodontology Published by John Wiley & Sons Ltd.

  16. [Subgingival irrigation combined with scaling and root planing. Results of a study with chlorhexidine and sodium hypochlorite].

    Science.gov (United States)

    Kamagate, A; Kone, D; Coulibaly, N T; Ahnoux, A

    2005-03-01

    Scaling and root planning is more and more associated with subgingival irrigation in chronics periodontal treatment. It is unreasonable to expect to control periodontal infections by mechanical treatment alone. Most patients do not achieve the necessary level of manual dexterity or motivation to control their plaque at home. It is rather better to deliver antimicrobial agents directly into the periodontal pocket. The aim of this study is to evaluate the action of subgingival irrigation associated to periodontal scaling on the clinical parameters and to compare the effects of chlorhexidine (Eludril) and sodium hypochlorite (Dakin Cooper) on adult's chronics periodontitis treatment. At the level of Plaque Index, Gingival Index and Bleeding on Probing, the results show that Eludril irrigation associated to scaling is lightly efficacious than Dakin cooper irrigation associated to scaling. And, the last one also is lightly efficacious than scaling alone. However, at the level of pocket depth, scaling alone has been also effective than scaling associated with subgingival irrigation.

  17. Efecto del tratamiento periodontal sobre la microbiota subgingival en pacientes con preeclampsia

    Directory of Open Access Journals (Sweden)

    Adriana Jaramillo

    2012-06-01

    Full Text Available Introducción. Pocos estudios han descrito la microbiota subgingival en mujeres embarazadas con preeclampsia leve. Objetivo. Identificar cambios periodontales y de la microbiota subgingival en mujeres embarazadas con preeclampsia, después del tratamiento periodontal. Materiales y métodos. En un análisis secundario de un ensayo clínico de asignación aleatoria, se estudiaron 57 pacientes con preeclampsia en el Hospital Universitario del Valle de Cali. Se asignaron al azar 31 al grupo de intervención periodontal (detartraje y alisado subgingival ultrasónico y manual durante su embarazo y otras 26 al grupo control (profilaxis supragingival. Se determinaron los parámetros clínicos periodontales y la microbiota subgingival a la inclusión al estudio y en el posparto. Se evaluaron 8 bacterias periodontopáticas y 2 virus herpes por reacción en cadena de la polimerasa. Se usaron las pruebas de ji al cuadrado, test de McNemar o t de Student, con un nivel de significancia de p≤0,05. Resultados. Los grupos fueron comparables en las variables clínicas y microbiológicas al inicio del estudio. El tratamiento periodontal redujo el promedio de la profundidad de bolsa en el grupo de intervención de 2,44±0,31 a 2,31±0,24 mm (p=0,000 y en el grupo control de 2,58±0,37 a 2,44±0,39 mm (p=0,000,y el índice de sangrado, de 16,4±1,5 a 7,9±0,7 % en el primero (p=0,000, y de 17,1±1,8 a 10±0,9 %, en el segundo (p=0,002. La frecuencia de detección de microorganismos no varió de manera significativa entre los grupos. Conclusión. El raspaje y alisado radicular, así como la profilaxis supragingival, redujeron de manera significativa la profundidad a la sonda y el índice de sangrado gingival. El tratamiento periodontal no fue más efectivo que la profilaxis para reducir los organismos periodontopáticos o los virus herpes.   doi: http://dx.doi.org/10.7705/biomedica.v32i2.661

  18. Biofilm Fixed Film Systems

    Directory of Open Access Journals (Sweden)

    Dipesh Das

    2011-09-01

    Full Text Available The work reviewed here was published between 2008 and 2010 and describes research that involved aerobic and anoxic biofilm treatment of water pollutants. Biofilm denitrification systems are covered when appropriate. References catalogued here are divided on the basis of fundamental research area or reactor types. Fundamental research into biofilms is presented in two sections, Biofilm Measurement and Characterization and Growth and Modeling. The reactor types covered are: trickling filters, rotating biological contactors, fluidized bed bioreactors, submerged bed biofilm reactors, biological granular activated carbon, membrane bioreactors, and immobilized cell reactors. Innovative reactors, not easily classified, are then presented, followed by a section on biofilms on sand, soil and sediment.

  19. [Comparison of subgingival debridement efficacy of air polishing and manual scaling].

    Science.gov (United States)

    Hu, Cong-jiao; Yin, Yuan-zheng; Guan, Dan-ping

    2015-10-01

    To assess the efficacy of subgingival air polishing and traditional manual scaling in 3-6 mm pockets. Patients with chronic periodontitis who were in the maintenance phase were randomly assigned to receive subgingival air polishing (experimental group) and manual scaling (control group) in 4 teeth with probing depths of 3 to 6 mm. Clinical variables including plaque index (PI), probing depth (PD), probing on bleeding (BOP) and gingival recession (GR) were recorded at baseline, 7 and 30 days post-treatment. "Pocket closure" [PD ≤ 4 mm and BOP⁻] was also calculated as supplementary data. The data of the 2 groups were compared using paired t test with SAS 8.2 software package. Thirty-one patients were enrolled and PI was 0.8 during the study. Both treatment procedures resulted in significant reductions of PD at day 7 (Pmanual scaling are both effective for improving clinical variables during supportive periodontal therapy (SPT) in teeth with probing depths of 3 to 6 mm. But the results reveal no significant difference between the 2 modalities.

  20. Differential reflectometry versus tactile sense detection of subgingival calculus in dentistry

    Science.gov (United States)

    Shakibaie, Fardad; Walsh, Laurence J.

    2012-10-01

    Detecting dental calculus is clinically challenging in dentistry. This study used typodonts with extracted premolar and molar teeth and simulated gingival tissue to compare the performance of differential reflectometry and periodontal probing. A total of 30 extracted teeth were set in an anatomical configuration in stone to create three typodonts. Clear polyvinyl siloxane impression material was placed to replicate the periodontal soft tissues. Pocket depths ranged from 10 to 15 mm. The three models were placed in a phantom head, and an experienced dentist assessed the presence of subgingival calculus first using the DetecTar (differential reflectometry) and then a periodontal probe. Scores from these two different methods were compared to the gold standard (direct examination of the root surface using 20× magnification) to determine the accuracy and reproducibility. Differential reflectometry was more accurate than tactile assessment (79% versus 60%), and its reproducibility was also higher (Cohen kappa 0.54 versus 0.39). Both methods performed better on single rooted premolar teeth than on multirooted teeth. These laboratory results indicate that differential reflectometry allows more accurate and reproducible detection of subgingival calculus than conventional probing, and supports its use for supplementing traditional periodontal examination methods in dental practice.

  1. The Impact of Residual Subgingival Cement on Biological Complications Around Dental Implants: A Systematic Review.

    Science.gov (United States)

    Quaranta, Alessandro; Lim, Zhuo Wei; Tang, Joyce; Perrotti, Vittoria; Leichter, Jonathan

    2017-06-01

    To perform a systematic review on the impact of residual subgingival cement on peri-implant diseases and crestal bone loss. MEDLINE, SCOPUS, ISI Web of Knowledge and Cochrane Central Register of Controlled Trials (CENTRAL) databases were used to identify articles published without time limits. A total of 6 articles were selected for a total of 389 patients (687 implants). The studies were heterogeneous and had a moderate-to-high risk of bias, but met the inclusion criteria. Four of 6 studies were published by the same research group and assessed similar populations over time. A positive relationship between residual cement and peri-implant inflammation was observed. Data on peri-implant probing depths and crestal bone loss were reported in 1 study. Residual subgingival cement seems to be strongly associated with peri-implant mucositis which is a risk factor for increased probing depths crestal bone loss and peri-implantitis. Zinc oxide eugenol cements should be preferred to resin cements especially in patients with a history of periodontitis.

  2. Pseudomonas aeruginosa Biofilm Infections

    DEFF Research Database (Denmark)

    Rybtke, Morten; Hultqvist, Louise Dahl; Givskov, Michael

    2015-01-01

    Studies of biopsies from infectious sites, explanted tissue and medical devises have provided evidence that biofilms are the underlying cause of a variety of tissue-associated and implant-associated recalcitrant human infections. With a need for novel anti-biofilm treatment strategies, research...... in biofilm infection microbiology, biofilm formation mechanisms and biofilm-associated antimicrobial tolerance has become an important area in microbiology. Substantial knowledge about biofilm formation mechanisms, biofilm-associated antimicrobial tolerance and immune evasion mechanisms has been obtained...... through work with biofilms grown in in vitro experimental setups, and the relevance of this information in the context of chronic infections is being investigated by the use of animal models of infection. Because our current in vitro experimental setups and animal models have limitations, new advanced...

  3. Fluoride in Dental Biofilm Varies across Intra-Oral Regions.

    Science.gov (United States)

    Staun Larsen, Line; Baelum, Vibeke; Tenuta, Livia Maria Andaló; Richards, Alan; Nyvad, Bente

    2017-01-01

    Information on differences in biofilm fluoride concentration across intra-oral regions may help explain the distribution of caries within the dentition. The aim of this cross-sectional study was to describe the fluoride concentration in saliva and in biofilm fluid and biofilm solids across 6 intra-oral regions. Unstimulated whole saliva was collected from 42 participants and biofilm harvested from the buccal sites in the 4 molar and 2 anterior regions. Samples were collected at least 1 h after use of fluoride dentifrice. No attempt was made to control the participants' food consumption or use of other topical agents. Centrifuged saliva, biofilm fluid, and biofilm solids were analysed for fluoride using a fluoride ion-selective electrode, adapted for microanalysis. Fluoride in biofilm varied across intra-oral regions. The mean biofilm fluid fluoride concentrations across the oral cavity ranged from 11.6 to 16.8 µM, being statistically significantly higher in the upper anterior region than in any other region. In all regions the fluoride concentration in biofilm fluid was higher than in saliva. For biofilm solids the fluoride concentration was highest in the lower anterior region (2,461 μmol/kg) and lowest in the lower molar regions (388 and 406 μmol/kg, respectively). Within biofilm, the solids contained most of the fluoride (81 to >99%). The biofilm fluid fluoride concentration was significantly positively associated with salivary fluoride and only marginally associated with that of biofilm solids. In conclusion, this study has shown pronounced differences in fluoride distribution across intra-oral regions and compartments. This shows that the sampling site is a crucial factor for studies of biofilm fluoride. © 2017 S. Karger AG, Basel.

  4. Evaluation of the Inhibition of Culturable Enterococcus faecium, Escherichia coli, or Aeromonas hydrophilia by an Existing Drinking Water Biofilm

    Science.gov (United States)

    Experiments were conducted to determine if an existing biofilm could act as a inhibitor to introduced microorganisms, preventing them from being incorporated into the existing biofilm or forming a biofilm. Biofilm sampling coupons were challenged by a solution of a single indica...

  5. Osteoblast integration of dental implant materials after challenge by sub-gingival pathogens : a co-culture study in vitro

    NARCIS (Netherlands)

    Zhao, Bingran; van der Mei, Henny C; Rustema-Abbing, Minie; Busscher, Henk J; Ren, Yijin

    2015-01-01

    Sub-gingival anaerobic pathogens can colonize an implant surface to compromise osseointegration of dental implants once the soft tissue seal around the neck of an implant is broken. In vitro evaluations of implant materials are usually done in monoculture studies involving either tissue integration

  6. THE INFLUENCE OF SURFACE-FREE ENERGY ON SUPRAGINGIVAL AND SUBGINGIVAL PLAQUE MICROBIOLOGY - AN IN-VIVO STUDY ON IMPLANTS

    NARCIS (Netherlands)

    QUIRYNEN, M; VANDERMEI, HC; BOLLEN, CML; VANDENBOSSCHE, LH; DOORNBUSCH, GI; VANSTEENBERGHE, D; BUSSCHER, HJ

    THE INFLUENCE OF SURFACE FREE ENERGY on supra- and subgingival plaque microbiology was examined in 9 patients with functional fixed prostheses supported by endosseous titanium implants. Two abutments (trans-mucosal part of the 2 stage implant) were replaced by either a new titanium abutment or a

  7. Chlorine dioxide disinfection of single and dual species biofilms, detached biofilm and planktonic cells.

    Science.gov (United States)

    Behnke, Sabrina; Camper, Anne K

    2012-01-01

    Disinfection efficacy testing is usually done with planktonic cells or more recently, biofilms. While disinfectants are much less effective against biofilms compared to planktonic cells, questions regarding the disinfection tolerance of detached biofilm clusters remain largely unanswered. Burkholderia cepacia and Pseudomonas aeruginosa were grown in chemostats and biofilm tubing reactors, with the tubing reactor serving as a source of detached biofilm clusters. Chlorine dioxide susceptibility was assessed for B. cepacia and P. aeruginosa in these three sample types as monocultures and binary cultures. Similar doses of chlorine dioxide inactivated samples of chemostat and tubing reactor effluent and no statistically significant difference between the log(10) reductions was found. This contrasts with chlorine, shown previously to be generally less effective against detached biofilm particles. Biofilms were more tolerant and required chlorine dioxide doses ten times higher than chemostat and tubing reactor effluent samples. A second species was advantageous in all sample types and resulted in lower log(10) reductions when compared to the single species cultures, suggesting a beneficial interaction of the species.

  8. Matrix-Gla Protein rs4236 [A/G] gene polymorphism and serum and GCF levels of MGP in patients with subgingival dental calculus.

    Science.gov (United States)

    Doğan, Gülnihal Emrem; Demir, Turgut; Aksoy, Hülya; Sağlam, Ebru; Laloğlu, Esra; Yildirim, Abdulkadir

    2016-10-01

    Matrix-Gla Protein (MGP) is one of the major Gla-containing protein associated with calcification process. It also has a high affinity for Ca 2+ and hydroxyapatite. In this study we aimed to evaluate the MGP rs4236 [A/G] gene polymorphism in association with subgingival dental calculus. Also a possible relationship between MGP gene polymorphism and serum and GCF levels of MGP were examined. MGP rs4236 [A/G] gene polymorphism was investigated in 110 patients with or without subgingival dental calculus, using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) techniques. Additionally, serum and GCF levels of MGP of the patients were compared according to subgingival dental calculus. Comparison of patients with and without subgingival dental calculus showed no statistically significant difference in MGP rs4236 [A/G] gene polymorphism (p=0.368). MGP concentrations in GCF of patients with subgingival dental calculus were statistically higher than those without subgingival dental calculus (p=0.032). However, a significant association was not observed between the genotypes of AA, AG and GG of the MGP rs4236 gene and the serum and GCF concentrations of MGP in subjects. In this study, it was found that MGP rs4236 [A/G] gene polymorphism was not to be associated with subgingival dental calculus. Also, that GCF MGP levels were detected higher in patients with subgingival dental calculus than those without subgingival dental calculus independently of polymorphism, may be the effect of adaptive mechanism to inhibit calculus formation. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. Subgingival microflora and antibody responses against periodontal bacteria of young Japanese patients with type 1 diabetes mellitus.

    Science.gov (United States)

    Takahashi, K; Nishimura, F; Kurihara, M; Iwamoto, Y; Takashiba, S; Miyata, T; Murayama, Y

    2001-10-01

    Periodontal disease is a complication of patients with type 1 diabetes mellitus (T1DM), although the mechanisms responsible for this relationship remain unclear. The aim of this study was to examine oral manifestations and the prevalence of periodontal pathogens from subgingival plaque samples and serum IgG antibody levels against them in young Japanese type 1 diabetic subjects. One hundred and seventeen Japanese T1DM subjects (53 male, 64 female, mean age +/- SD, 16 +/- 6.5 years) participated in this study. Thirty-nine periodontally healthy, age-matched nondiabetics served as controls. T1DM subjects were clinically assigned into three groups: 12 periodontitis, 32 gingivitis and 73 periodontally healthy. Microbiological tests for four periodontal pathogens, Porphyromonas gingivalis, Actinobacillus actinomycetemcomitans, Prevotella intermedia and Capnocytophaga ochracea were performed using 16S ribosomal RNA-based polymerase chain reaction methods. Serum IgG antibody levels against 12 periodontal bacteria including the four species assessed by polymerase chain reaction were measured by enzyme-linked immunosorbent assay. In the T1DM subjects, the Periodontitis group had a significantly longer mean duration of diabetes and a higher percentages of subjects harbouring P. gingivalis and P. intermedia than the Periodontally Healthy group. Serum IgG antibody levels against P. gingivalis were significantly elevated in the Periodontitis group compared with Gingivitis and Periodontally Healthy groups. These results indicate that Japanese T1DM subjects are a high-risk group for periodontal disease and both P. gingivalis infection and duration of T1DM are risk factors for the progression of periodontitis in patients with T1DM.

  10. D-Galactose as an autoinducer 2 inhibitor to control the biofilm formation of periodontopathogens.

    Science.gov (United States)

    Ryu, Eun-Ju; Sim, Jaehyun; Sim, Jun; Lee, Julian; Choi, Bong-Kyu

    2016-09-01

    Autoinducer 2 (AI-2) is a quorum sensing molecule to which bacteria respond to regulate various phenotypes, including virulence and biofilm formation. AI-2 plays an important role in the formation of a subgingival biofilm composed mostly of Gram-negative anaerobes, by which periodontitis is initiated. The aim of this study was to evaluate D-galactose as an inhibitor of AI-2 activity and thus of the biofilm formation of periodontopathogens. In a search for an AI-2 receptor of Fusobacterium nucleatum, D-galactose binding protein (Gbp, Gene ID FN1165) showed high sequence similarity with the ribose binding protein (RbsB), a known AI-2 receptor of Aggregatibacter actinomycetemcomitans. D-Galactose was evaluated for its inhibitory effect on the AI-2 activity of Vibrio harveyi BB152 and F. nucleatum, the major coaggregation bridge organism, which connects early colonizing commensals and late pathogenic colonizers in dental biofilms. The inhibitory effect of D-galactose on the biofilm formation of periodontopathogens was assessed by crystal violet staining and confocal laser scanning microscopy in the absence or presence of AI-2 and secreted molecules of F. nucleatum. D-Galactose significantly inhibited the AI-2 activity of V. harveyi and F. nucleatum. In addition, D-galactose markedly inhibited the biofilm formation of F. nucleatum, Porphyromonas gingivalis, and Tannerella forsythia induced by the AI-2 of F. nucleatum without affecting bacterial growth. Our results demonstrate that the Gbp may function as an AI-2 receptor and that galactose may be used for prevention of the biofilm formation of periodontopathogens by targeting AI-2 activity.

  11. Multidisciplinary management of subgingival crown-root fracture of an immature permanent maxillary central incisor

    Directory of Open Access Journals (Sweden)

    Samir Zahedpasha

    2012-01-01

    Full Text Available This case report describes the multidisciplinary management of subgingival horizontal crown-root fracture of an immature permanent maxillary central incisor in a 10-year-old boy. After removal of the fractured fragment, pulpotomy was performed within 48 h from the injury to promote apexogenesis. The tooth was orthodontically extruded until the fracture line was located above the alveolar bone level. Frenectomy, supracrestal fiberotomy, and crown lengthening were performed after adequate stabilization of the extruded tooth for 5 months. Finally, the tooth was restored with composite resin by using the acid etch technique. This report highlights that a multidisciplinary treatment approach with strict cooperation among specialists to manage a complicated crown-root fracture can save and restore a traumatized immature permanent tooth.

  12. Sampling

    CERN Document Server

    Thompson, Steven K

    2012-01-01

    Praise for the Second Edition "This book has never had a competitor. It is the only book that takes a broad approach to sampling . . . any good personal statistics library should include a copy of this book." —Technometrics "Well-written . . . an excellent book on an important subject. Highly recommended." —Choice "An ideal reference for scientific researchers and other professionals who use sampling." —Zentralblatt Math Features new developments in the field combined with all aspects of obtaining, interpreting, and using sample data Sampling provides an up-to-date treat

  13. Antimicrobial Tolerance in Biofilms

    Science.gov (United States)

    Stewart, Philip S.

    2015-01-01

    The tolerance of microorganisms in biofilms to antimicrobial agents is examined through a meta-analysis of literature data. A numerical tolerance factor comparing the rates of killing in the planktonic and biofilm states is defined to provide a quantitative basis for the analysis. Tolerance factors for biocides and antibiotics range over three orders of magnitude. This variation is not explained by taking into account the molecular weight of the agent, the chemistry of the agent, the substratum material, or the speciation of the microorganisms. Tolerance factors do depend on the areal cell density of the biofilm at the time of treatment and on the age of the biofilm as grown in a particular experimental system. This suggests that there is something that happens during biofilm maturation, either physical or physiological, that is essential for full biofilm tolerance. Experimental measurements of antimicrobial penetration times in biofilms range over orders of magnitude, with slower penetration (>12 min) observed for reactive oxidants and cationic molecules. These agents are retarded through the interaction of reaction, sorption, and diffusion. The specific physiological status of microbial cells in a biofilm contributes to antimicrobial tolerance. A conceptual framework for categorizing physiological cell states is discussed in the context of antimicrobial susceptibility. It is likely that biofilms harbor cells in multiple states simultaneously (e.g., growing, stress-adapted, dormant, inactive) and that this physiological heterogeneity is an important factor in the tolerance of the biofilm state. PMID:26185072

  14. Mucosal biofilm detection in chronic otitis media

    DEFF Research Database (Denmark)

    Wessman, Marcus; Bjarnsholt, Thomas; Eickhardt-Sørensen, Steffen Robert

    2015-01-01

    The objectives of this study were to examine middle ear biopsies from Greenlandic patients with chronic otitis media (COM) for the presence of mucosal biofilms and the bacteria within the biofilms. Thirty-five middle ear biopsies were obtained from 32 Greenlandic COM patients admitted to ear...... surgery. All biopsies were examined by means of peptide nucleic acid-fluorescent in situ hybridization (PNA-FISH), and if possible culture and polymerase chain reaction (PCR) of the 16s rDNA and sequencing. Light microscopy and confocal laser scanning microscopy were used. Skin biopsies from 23...... of 20 (35 %) usable middle ear biopsies, and in two out of ten (20 %) usable control samples. There was no association between biofilm findings and PCR and 16s sequencing. Staphylococci were the most common bacteria in bacterial culture. We found evidence of bacterial biofilms in 43 % of middle ear...

  15. Stress tolerance of Methylobacterium biofilms in bathrooms.

    Science.gov (United States)

    Yano, Takehisa; Kubota, Hiromi; Hanai, Junya; Hitomi, Jun; Tokuda, Hajime

    2013-01-01

    A comprehensive survey of microbial flora within pink biofilms in bathrooms was performed. Pink biofilms develop relatively rapidly in bathrooms, can be difficult to remove, and are quick to recur. Bacterium-sized cells were found to be predominant in 42 pink biofilms in Japan using a scanning electron microscope. Methylobacterium strains were detected from all samples in bathrooms by an isolation method. To explain this predominance, 14 biofilm samples were analyzed by fluorescence in situ hybridization. Methylobacterium was indicated to be the major genus in all biofilms. The isolated Methylobacterium survived after contact with 1.0% cleaning agents, including benzalkonium chloride for 24 h. Their tolerance did not differ under biofilm-like conditions on fiber reinforced plastics (FRP), a general material of bath tubs, floors, and walls. Also, the strains exhibited higher tolerance to desiccation than other isolated species on FRP. Some Methylobacterium survived and exhibited potential to grow after four weeks of desiccation without any nutrients. These specific characteristics could be a cause of their predominance in bathrooms, an environment with rapid flowing water, drying, low nutrients, and occasional exposure to cleaning agents.

  16. Multispecies Biofilms and Host Responses: “Discriminating the Trees from the Forest”

    Science.gov (United States)

    Peyyala, R.; Ebersole, J.L.

    2014-01-01

    Periodontal diseases reflect a tissue destructive process of the hard and soft tissues of the periodontium that are initiated by the accumulation of multispecies bacterial biofilms in the subgingival sulcus. This accumulation, in both quantity and quality of bacteria, results in a chronic immunoinflammatory response of the host to control this noxious challenge, leading to collateral damage of the tissues. As knowledge of the characteristics of the host-bacterial interactions in the oral cavity has expanded, new knowledge has become available on the complexity of the microbial challenge and the repertoire of host responses to this challenge. Recent results from the Human Microbiome Project continue to extend the array of taxa, genera, and species of bacteria that inhabit the multiple niches in the oral cavity; however, there is rather sparse information regarding variations in how host cells discriminate commensal from pathogenic species, as well as how the host response is affected by the 3-dimensional architecture and interbacterial interactions that occur in the oral biofilms. This review provides some insights into thes- processes by including existing literature on the biology of nonoral bacterial biofilms, and the more recent literature just beginning to document how the oral cavity responds to multispecies biofilms. PMID:23141757

  17. Effect of low direct current on anaerobic multispecies biofilm adhering to a titanium implant surface.

    Science.gov (United States)

    Sahrmann, Philipp; Zehnder, Matthias; Mohn, Dirk; Meier, André; Imfeld, Thomas; Thurnheer, Thomas

    2014-08-01

    Peri-implantitis is caused by biofilm adhering to the implant. It has been shown that bactericidal electrolysis products are generated when a low direct current is applied to a titanium implant used as the anode. The hypothesis of this study was that low-current electrolysis would eradicate viable bacteria in a simulated subgingival multispecies biofilm adhering to a titanium implant surface. Biofilms consisting of eight anaerobic species were grown on pellicle-coated titanium discs with sand-blasted, acid-etched, large-grit (SLA; Straumann, Basel, Switzerland) surface. After 40.5 hours of growth, discs were treated with 10 mA for 10 minutes in an electrolytical setup with physiological saline and gelatin. Low direct current at discs used as the cathode caused a reduction of three to four orders of magnitude in viable counts, while no viable bacteria were recovered from anode discs (Mann-Whitney U-test, p biofilm detachment at the cathode and reduced viability at the anode. Electrochemical treatment of diseased implants appears to be promising and well worth investigating further. © 2012 Wiley Periodicals, Inc.

  18. Differences in the composition of the subgingival microbiota of two periodontitis populations of different geographical origin. A comparison between Spain and The Netherlands

    NARCIS (Netherlands)

    Sanz, M; van Winkelhoff, AJ; Herrera, D; Dellemijn-Kippuw, N; Simon, R; Winkel, E

    2000-01-01

    The purpose of this study was to compare the subgingival microbiota of two geographically distinct patient populations using identical clinical and bacteriological methods. Adult patients with a diagnosis of periodontitis were consecutively selected according to pre-defined clinical criteria.

  19. Pseudomonas aeruginosa biofilm infections

    DEFF Research Database (Denmark)

    Tolker-Nielsen, Tim

    2014-01-01

    Bacteria in natural, industrial and clinical settings predominantly live in biofilms, i.e., sessile structured microbial communities encased in self-produced extracellular matrix material. One of the most important characteristics of microbial biofilms is that the resident bacteria display...... a remarkable increased tolerance toward antimicrobial attack. Biofilms formed by opportunistic pathogenic bacteria are involved in devastating persistent medical device-associated infections, and chronic infections in individuals who are immune-compromised or otherwise impaired in the host defense. Because...... the use of conventional antimicrobial compounds in many cases cannot eradicate biofilms, there is an urgent need to develop alternative measures to combat biofilm infections. The present review is focussed on the important opportunistic pathogen and biofilm model organism Pseudomonas aeruginosa. Initially...

  20. Staphylococcal biofilm disassembly

    OpenAIRE

    Boles, Blaise R.; Horswill, Alexander R.

    2011-01-01

    Staphylococcus aureus and Staphylococcus epidermidis are a frequent cause of biofilm-associated infections that are a tremendous burden on our healthcare system. Staphylococcal biofilms exhibit extraordinary resistance to antimicrobial killing, limiting the efficacy of antibiotic therapy and often require surgical intervention to remove infected tissues or implanted devices. Recent work has provided new insight into the molecular basis of biofilm development in these opportunistic pathogens. ...

  1. Biofilm-forming activity of bacteria isolated from toilet bowl biofilms and the bactericidal activity of disinfectants against the isolates.

    Science.gov (United States)

    Mori, Miho; Gomi, Mitsuhiro; Matsumune, Norihiko; Niizeki, Kazuma; Sakagami, Yoshikazu

    2013-01-01

    To evaluate the sanitary conditions of toilets, the bacterial counts of the toilet bowl biofilms in 5 Kansai area and 11 Kansai and Kanto area homes in Japan were measured in winter and summer seasons, respectively. Isolates (128 strains) were identified by analyzing 16S ribosomal RNA sequences. The number of colonies and bacterial species from biofilms sampled in winter tended to be higher and lower, respectively, than those in summer. Moreover, the composition of bacterial communities in summer and winter samples differed considerably. In summer samples, biofilms in Kansai and Kanto areas were dominated by Blastomonas sp. and Mycobacterium sp., respectively. Methylobacterium sp. was detected in all toilet bowl biofilms except for one sample. Methylobacterium sp. constituted the major presence in biofilms along with Brevundimonas sp., Sphingomonas sp., and/or Pseudomonas sp. The composition ratio of the sum of their genera was 88.0 from 42.9% of the total bacterial flora. The biofilm formation abilities of 128 isolates were investigated, and results suggested that Methylobacterium sp. and Sphingomonas sp. were involved in biofilm formation in toilet bowls. The biofilm formation of a mixed bacteria system that included bacteria with the highest biofilm-forming ability in a winter sample was greater than mixture without such bacteria. This result suggests that isolates possessing a high biofilm-forming activity are involved in the biofilm formation in the actual toilet bowl. A bactericidal test against 25 strains indicated that the bactericidal activities of didecyldimethylammonium chloride (DDAC) tended to be higher than those of polyhexamethylene biguanide (PHMB) and N-benzyl-N,N-dimethyldodecylammonium chloride (ADBAC). In particular, DDAC showed high bactericidal activity against approximately 90% of tested strains under the 5 h treatment.

  2. Comparing the Chlorine Disinfection of Detached Biofilm Clusters with Those of Sessile Biofilms and Planktonic Cells in Single- and Dual-Species Cultures ▿ †

    Science.gov (United States)

    Behnke, Sabrina; Parker, Albert E.; Woodall, Dawn; Camper, Anne K.

    2011-01-01

    Although the detachment of cells from biofilms is of fundamental importance to the dissemination of organisms in both public health and clinical settings, the disinfection efficacies of commonly used biocides on detached biofilm particles have not been investigated. Therefore, the question arises whether cells in detached aggregates can be killed with disinfectant concentrations sufficient to inactivate planktonic cells. Burkholderia cepacia and Pseudomonas aeruginosa were grown in standardized laboratory reactors as single species and in coculture. Cluster size distributions in chemostats and biofilm reactor effluent were measured. Chlorine susceptibility was assessed for planktonic cultures, attached biofilm, and particles and cells detached from the biofilm. Disinfection tolerance generally increased with a higher percentage of larger cell clusters in the chemostat and detached biofilm. Samples with a lower percentage of large clusters were more easily disinfected. Thus, disinfection tolerance depended on the cluster size distribution rather than sample type for chemostat and detached biofilm. Intact biofilms were more tolerant to chlorine independent of species. Homogenization of samples led to significantly increased susceptibility in all biofilm samples as well as detached clusters for single-species B. cepacia, B. cepacia in coculture, and P. aeruginosa in coculture. The disinfection efficacy was also dependent on species composition; coculture was advantageous to the survival of both species when grown as a biofilm or as clusters detached from biofilm but, surprisingly, resulted in a lower disinfection tolerance when they were grown as a mixed planktonic culture. PMID:21856824

  3. Comparing the chlorine disinfection of detached biofilm clusters with those of sessile biofilms and planktonic cells in single- and dual-species cultures.

    Science.gov (United States)

    Behnke, Sabrina; Parker, Albert E; Woodall, Dawn; Camper, Anne K

    2011-10-01

    Although the detachment of cells from biofilms is of fundamental importance to the dissemination of organisms in both public health and clinical settings, the disinfection efficacies of commonly used biocides on detached biofilm particles have not been investigated. Therefore, the question arises whether cells in detached aggregates can be killed with disinfectant concentrations sufficient to inactivate planktonic cells. Burkholderia cepacia and Pseudomonas aeruginosa were grown in standardized laboratory reactors as single species and in coculture. Cluster size distributions in chemostats and biofilm reactor effluent were measured. Chlorine susceptibility was assessed for planktonic cultures, attached biofilm, and particles and cells detached from the biofilm. Disinfection tolerance generally increased with a higher percentage of larger cell clusters in the chemostat and detached biofilm. Samples with a lower percentage of large clusters were more easily disinfected. Thus, disinfection tolerance depended on the cluster size distribution rather than sample type for chemostat and detached biofilm. Intact biofilms were more tolerant to chlorine independent of species. Homogenization of samples led to significantly increased susceptibility in all biofilm samples as well as detached clusters for single-species B. cepacia, B. cepacia in coculture, and P. aeruginosa in coculture. The disinfection efficacy was also dependent on species composition; coculture was advantageous to the survival of both species when grown as a biofilm or as clusters detached from biofilm but, surprisingly, resulted in a lower disinfection tolerance when they were grown as a mixed planktonic culture.

  4. Visualizing the dental biofilm matrix by means of fluorescence lectin-binding analysis

    OpenAIRE

    Tawakoli, Pune N.; Neu, Thomas R.; Busck, Mette M.; Kuhlicke, Ute; Schramm, Andreas; Attin, Thomas; Wiedemeier, Daniel B.; Schlafer, Sebastian

    2017-01-01

    ABSTRACT The extracellular matrix is a poorly studied, yet important component of dental biofilms. Fluorescence lectin-binding analysis (FLBA) is a powerful tool to characterize glycoconjugates in the biofilm matrix. This study aimed to systematically investigate the ability of 75 fluorescently labeled lectins to visualize and quantify extracellular glycoconjugates in dental biofilms. Lectin binding was screened on pooled supragingival biofilm samples collected from 76 subjects using confocal...

  5. Antibiotic resistance and ndvB gene expression among biofilm ...

    African Journals Online (AJOL)

    A novel antibiotic resistant mechanism among biofilms is glucan-mediated sequestration in which ndvB gene encodes a glucosyltransferase involved in the formation of this glucans. We studied the biofilm formation and antibiotic susceptibility pattern of P. aeruginosa isolated from clinical samples, and measured the ...

  6. Use of the Syrian golden hamster for the induction of intraoral abscesses by sutures contaminated with human subgingival plaque.

    Science.gov (United States)

    Wasfy, M O; McMahon, K T; Santos, A C; Minah, G E; Falkler, W A; Lloyd, D R

    1994-02-01

    Analysis of normal oral flora in 150 cheek pouches of hamsters (Mesocricetus auratus) defined the microbial working environment and demonstrated the absence of human oral black-pigmented bacteria. Silk sutures saturated with Porphyromonas gingivalis, Prevotella intermedia or subgingival plaque were used to close wounds made in hamster's cheek pouches. Abscesses were formed when sutures had solitary P. gingivalis or other bacteria mixed with P. gingivalis or when P. intermedia was mixed with other bacteria besides P. gingivalis. A concentration of black-pigmented bacteria emanating from 3 x 10(5) colony-forming units/inoculum was required for abscess formation. Six abscesses (14.3%) were developed in association with the presence of other odontopathic bacteria, primarily Fusobacterium nucleatum and Actinomyces viscosus. The hamster cheek pouch with iatrogenic wounds closed with plaque-impregnated sutures is a novel and effective model to study the pathology of wound infections and virulence of human subgingival organisms.

  7. Diagnosis and understanding of chronic biofilm infections

    DEFF Research Database (Denmark)

    Thomsen, Trine Rolighed

    2016-01-01

    Title: Diagnosis and understanding of chronic biofilm infections. Name: Trine Rolighed Thomsen Aalborg University and Danish Technological Institute, Denmark Recent evidence suggests that the microbial community, its spatial distribution and activity play an important role in the prolongation......, anaerobic or unculturable bacteria living in biofilms. Thus, diagnosis of chronic infections is challenged by lack of appropriate sampling strategies and by limitations in microbiological testing methods. The purpose of this study was to improve sampling and diagnosis of chronic infections, especially...... considering the biofilm issue. Systematic and optimized sampling of various specimen types was performed. Extended culture, optimized DNA extraction, quantitative PCR, cloning, next generation sequencing and PNA FISH were applied on different types of specimens for optimized diagnosis. For further...

  8. Orthodontic extrusion of subgingivally fractured tooth using a removable appliance: An alternative treatment to reestablish biological width

    Directory of Open Access Journals (Sweden)

    Kanika Gupta Verma

    2014-01-01

    Full Text Available Restoration of a traumatically injured tooth presents a clinical challenge for a predictable aesthetic outcome. This case report describes a multidisciplinary approach of a subgingivally fractured permanent maxillary central incisor. A removable orthodontic appliance was used for orthodontic extrusion of root, and surgical gingival recontouring was done with electrocautery to reestablish the biological width. Form and function were restored establishing biological width and esthetics was repaired with porcelain fused to metal crown.

  9. Biofilm production and antibiotic susceptibility profiles of ...

    African Journals Online (AJOL)

    Jane

    2011-10-24

    Oct 24, 2011 ... determining the biofilm producing capability and antibiotic resistance profiles of the S. aureus isolated from drinking water and clinical samples from HIV patients in the Limpopo Province. S. aureus strains isolated from clinical samples including urine, sputum, and stools obtained from HIV and AIDS patients.

  10. Subgingival bacteria in a case of prepubertal periodontitis, before and one year after extractions of the affected primary teeth.

    Science.gov (United States)

    Ram, D; Bimstein, E

    1994-01-01

    The treatment of children with prepubertal periodontitis (PP), may be complicated by the extent of the lesions and the possibility of tetracycline stain of the developing permanent dentition. Therefore, with the purpose of preventing the infection of permanent teeth during the mixed dentition, it has been recommended that the treatment of children with PP, should include the early extraction of the primary teeth affected with alveolar bone loss (ABL). Still, there is little evidence which confirms that extraction of the affected primary teeth do in fact reduce the periodonto-pathogens load of the subgingival plaque. The present study reports values of colony forming units (CFU) of total anaerobic bacteria, Actinobacillus actynomicetemcomitans (Aa) and Porphyromonas gingivalis (Pg) from the subgingival plaque from a child with PP, collected immediately before and 1 year after extractions of the primary teeth affected with ABL. CFU of Aa and Pg developed only from the subgingival plaque collected before the extraction of the primary teeth affected with ABL. These findings suggest that in cases of PP, extraction of the affected primary teeth may reduce the possibility of infection of the periodontum of the permanent teeth during the mixed dentition period.

  11. Hydraulic resistance of biofilms

    KAUST Repository

    Dreszer, C.

    2013-02-01

    Biofilms may interfere with membrane performance in at least three ways: (i) increase of the transmembrane pressure drop, (ii) increase of feed channel (feed-concentrate) pressure drop, and (iii) increase of transmembrane passage. Given the relevance of biofouling, it is surprising how few data exist about the hydraulic resistance of biofilms that may affect the transmembrane pressure drop and membrane passage. In this study, biofilms were generated in a lab scale cross flow microfiltration system at two fluxes (20 and 100Lm-2h-1) and constant cross flow (0.1ms-1). As a nutrient source, acetate was added (1.0mgL-1 acetate C) besides a control without nutrient supply. A microfiltration (MF) membrane was chosen because the MF membrane resistance is very low compared to the expected biofilm resistance and, thus, biofilm resistance can be determined accurately. Transmembrane pressure drop was monitored. As biofilm parameters, thickness, total cell number, TOC, and extracellular polymeric substances (EPS) were determined, it was demonstrated that no internal membrane fouling occurred and that the fouling layer actually consisted of a grown biofilm and was not a filter cake of accumulated bacterial cells. At 20Lm-2h-1 flux with a nutrient dosage of 1mgL-1 acetate C, the resistance after 4 days reached a value of 6×1012m-1. At 100Lm-2h-1 flux under the same conditions, the resistance was 5×1013m-1. No correlation of biofilm resistance to biofilm thickness was found; Biofilms with similar thickness could have different resistance depending on the applied flux. The cell number in biofilms was between 4×107 and 5×108 cellscm-2. At this number, bacterial cells make up less than a half percent of the overall biofilm volume and therefore did not hamper the water flow through the biofilm significantly. A flux of 100Lm-2h-1 with nutrient supply caused higher cell numbers, more biomass, and higher biofilm resistance than a flux of 20Lm-2h-1. However, the biofilm thickness

  12. Relationship between expression of human gingival beta-defensins and levels of periodontopathogens in subgingival plaque.

    Science.gov (United States)

    Wang, P; Duan, D; Zhou, X; Li, X; Yang, J; Deng, M; Xu, Y

    2015-02-01

    Human beta-defensins (hBDs) are a group of antimicrobial peptides important in epithelial innate immunity, and their differential expression is associated with periodontal diseases. The aim of this study was to explore relationships among hBDs, total subgingival bacteria and periodontopathogens in healthy subjects and in patients with chronic periodontitis. The periodontal clinical parameters of 29 healthy subjects and 25 patients with chronic periodontitis were recorded. The relative expression of hBD1, hBD2 and hBD3 genes in gingival biopsies was measured using real-time PCR. The numbers of total bacteria and of Treponema denticola, Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Fusobacterium nucleatum and Tannerella forsythia in subgingival plaque were quantified by real-time PCR. Data were analyzed using the Mann-Whitney U-test and Spearman's rank correlation test. No significant differences in expression of the hBD genes were found between the group of healthy subjects and the group of patients with chronic periodontitis. Total bacteria and T. denticola were detected in all participants. F. nucleatum and T. forsythia were detected in all patients with chronic periodontitis and in 86.21% and 51.72%, respectively, of healthy volunteers. P. gingivalis and A. actinomycetemcomitans were detected in 24.14% and 17.24%, respectively, of the healthy group and in 84.00% and 12.00%, respectively, of the chronic periodontitis group. The prevalence of all bacteria, except A. actinomycetemcomitans, was significantly higher in the group of patients with chronic periodontitis than in the group of healthy subjects (p analyzing the data in different groups, total bacteria and hBD-2 were significantly correlated (r = -0.492, p = 0.026) only in the group of healthy subjects. The negative correlations between hBD-2 and total bacteria, especially in the group of healthy subjects, indicate that hBDs may play an important role by limiting an increase of

  13. Survival of Campylobacter jejuni in biofilms after chlorine treatment

    Directory of Open Access Journals (Sweden)

    Kunyaboon, S

    2006-09-01

    Full Text Available Survival of C. jejuni in biofilms isolated from two chicken houses in Thailand (FBRL-C04, FBRLB05 and FBRL-B06 after chlorine treatment was studied. Biofilm cultures were grown on stainless steel surface in 50% trypticase soy broth for 3 days, subsequently C. jejuni cells were allowed to attach to these biofilms for 4 h at 25ºC. Sodium hypochlorite was used to prepare sanitizing solution with active chlorine of 15 ppm and 25 ppm. Stainless steel coupons containing C. jejuni with and without biofilms were treated with chlorine for 30 sec and neutralized with 0.05% sodium thiosulfate. At both concentrations, C. jejuni were inactivated to lower than 1 log10CFU/cm2 when initial attachment load was approximately 4 log10CFU/cm2. However, C. jejuni in all samples treated with 15 ppm active chlorine were recovered in enrichment media. When treated with the higher concentration of chlorine, 25 ppm, C. jejuni in biofilm of FBRL-C04 (5/9, FBRL-B06 (1/9 and biofilm-free surface (1/9 could also be recovered. This indicates that chlorine treatment at 15 and 25 ppm could not completely inactivate C. jejuni attached to biofilms and biofilm-free surfaces. Biofilm of FBRL-C04 enhanced the survival of C. jejuni after chlorine treatment at 25 ppm although biofilm initial attachment as determined by plate count method was similar to that of other biofilms. Attachment load of viable biofilm cells may not contribute to enhanced survival of C. jejuni in chlorine treatment.

  14. Biofilms in wounds

    DEFF Research Database (Denmark)

    Cooper, R A; Bjarnsholt, Thomas; Alhede, M

    2014-01-01

    Following confirmation of the presence of biofilms in chronic wounds, the term biofilm became a buzzword within the wound healing community. For more than a century pathogens have been successfully isolated and identified from wound specimens using techniques that were devised in the nineteenth...... extracellular polymeric substances (EPS). Cells within such aggregations (or biofilms) display varying physiological and metabolic properties that are distinct from those of planktonic cells, and which contribute to their persistence. There are many factors that influence healing in wounds and the discovery...... of biofilms in chronic wounds has provided new insight into the reasons why. Increased tolerance of biofilms to antimicrobial agents explains the limited efficacy of antimicrobial agents in chronic wounds and illustrates the need to develop new management strategies. This review aims to explain the nature...

  15. Dental biofilm infections

    DEFF Research Database (Denmark)

    Larsen, Tove; Fiehn, Nils-Erik

    2017-01-01

    species at a site will build up and may eventually cause development of disease. Depending on local ecological factors, the composition of the dental biofilm may vary considerably. With access to excess carbohydrates, the dental biofilm will be dominated by mainly gram-positive carbohydrate...... and cause gingival inflammation and breakdown of supporting periodontal fibers and bone and ultimately tooth loss, i.e., gingivitis, chronic or aggressive periodontitis, and around dental implants, peri-implantitis. Furthermore, bacteria from the dental biofilm may spread to other parts of the body...... by bacteremia and cause systemic disease. Basically, prevention and treatment of dental biofilm infections are achieved by regular personal and professional removal of the dental biofilm....

  16. Visualizing the dental biofilm matrix by means of fluorescence lectin-binding analysis

    DEFF Research Database (Denmark)

    Tawakoli, Pune Nina; Neu, Thomas R; Busck, Mette Marie

    2017-01-01

    The extracellular matrix is a poorly studied, yet important component of dental biofilms. Fluorescence lectin-binding analysis (FLBA) is a powerful tool to characterize glycoconjugates in the biofilm matrix. This study aimed to systematically investigate the ability of 75 fluorescently labeled...... lectins to visualize and quantify extracellular glycoconjugates in dental biofilms. Lectin binding was screened on pooled supragingival biofilm samples collected from 76 subjects using confocal microscopy. FLBA was then performed with 10 selected lectins on biofilms grown in situ for 48 h in the absence...... in the dental biofilm matrix. The characterization and quantification of glycoconjugates in dental biofilms require a combination of several lectins. For 48-h-biofilms grown in absence of sucrose, AAL, Calsepa, HPA, LEA, and MNA-G are recommendable....

  17. The effect of berberine hydrochloride on Enterococcus faecalis biofilm formation and dispersion in vitro.

    Science.gov (United States)

    Chen, Lihua; Bu, Qianqian; Xu, Huan; Liu, Yuan; She, Pengfei; Tan, Ruichen; Wu, Yong

    2016-01-01

    Enterococcus faecalis (E. faecalis) is one of the major causes of biofilm infections. Berberine hydrochloride (BBH) has diverse pharmacological effects; however, the effects and mechanisms of BBH on E. faecalis biofilm formation and dispersion have not been reported. In this study, 99 clinical isolates from the urine samples of patients with urinary tract infections (UTIs) were collected and identified. Ten strains of E. faecalis with biofilm formation ability were studied. BBH inhibited E. faecalis biofilm formation and promoted the biofilm dispersion of E. faecalis. In addition, sortase A and esp expression levels were elevated during early E. faecalis biofilm development, whereas BBH significantly reduced their expression levels. The results of this study indicated that BBH effectively prevents biofilm formation and promotes biofilm dispersion in E. faecalis, most likely by inhibiting the expressions of sortase A and esp. Copyright © 2016 Elsevier GmbH. All rights reserved.

  18. Shifts of subgingival bacterial population after nonsurgical and pharmacological therapy of localized aggressive periodontitis, followed for 1 year by Ion Torrent PGM platform.

    Science.gov (United States)

    Campisciano, Giuseppina; Toschetti, Annamaria; Comar, Manola; Taranto, Rosanna Di; Berton, Federico; Stacchi, Claudio

    2017-01-01

    The possibility of targeting the hypervariable region V3 of the 16S rRNA gene using Ion Torrent Personal Genome Machine (PGM) could provide a complete analysis of subgingival plaque samples, potentially able to identify microbiological species missed by culture-based methods. A 16-year-old female smoker patient, affected by localized aggressive periodontitis, underwent a full-mouth disinfection protocol and was inserted in a 3-month recall program. Microbiological samples were collected at baseline and at 30, 100, 365 days follow-up and analyzed by Ion Torrent PGM. Capnocytophaga, Fusobacterium, Prevotella, and Treponema were the most represented pathogens at baseline. Nonsurgical treatment and systemic antibiotics drastically lowered the anaerobic species, and their presence remained limited after 100 days, while a consistent recolonization by anaerobic bacteria was detected at 365 days. The patient showed a general improvement of periodontal conditions. Differently from polymerase chain reaction and other microarray techniques, Ion Torrent performs a quantitative analysis of the microbiota, irrespective of the searched species. An accurate definition of the shifts of the bacterial community might help periodontal researchers for a better understanding of the impact of different treatment approaches or in intercepting nonresponsive conditions.

  19. Biofilm Cohesive Strength as a Basis for Biofilm Recalcitrance: Are Bacterial Biofilms Overdesigned?

    Science.gov (United States)

    Aggarwal, Srijan; Stewart, Philip S; Hozalski, Raymond M

    2015-01-01

    Bacterial biofilms are highly resistant to common antibacterial treatments, and several physiological explanations have been offered to explain the recalcitrant nature of bacterial biofilms. Herein, a biophysical aspect of biofilm recalcitrance is being reported on. While engineering structures are often overdesigned with a factor of safety (FOS) usually under 10, experimental measurements of biofilm cohesive strength suggest that the FOS is on the order of thousands. In other words, bacterial biofilms appear to be designed to withstand extreme forces rather than typical or average loads. In scenarios requiring the removal or control of unwanted biofilms, this emphasizes the importance of considering strategies for structurally weakening the biofilms in conjunction with bacterial inactivation.

  20. Daily biofilm control and oral health: consensus on the epidemiological challenge - Latin American Advisory Panel

    Directory of Open Access Journals (Sweden)

    Sigmar de Mello Rode

    2012-01-01

    Full Text Available Our understanding of dental plaque biofilm has evolved since the nonspecific plaque hypothesis that considered plaque as a nonspecific mass of native microorganisms that, because of lack of oral hygiene, builds up in proportions great enough to overcome the host resistance threshold and affect the tooth structure and tooth supporting tissues. A great diversity of microorganisms-over 700 species-was detected in the oral cavity, and evidence shows that the investigation of specific microorganisms or associations of microorganisms as etiological agents for periodontal diseases and caries is not a simplistic approach. Although clinical evidence shows that oral mechanical hygiene is fundamental to prevent and control caries and periodontal disease, it is important to highlight that optimal control is not achieved by most individuals. Thus the complementary use of chemotherapeutic agents has been investigated as a way to overcome the deficiencies of mechanical oral hygiene habits, insofar as they reduce both plaque formation and gingival inflammation, and represent a valid strategy to change the biofilm and maintain dental and periodontal health. The role of the dental professional is to monitor patients and offer them the best recommendations to preserve oral health throughout their life. With this in mind, chemical control should be indicated as part of daily oral hygiene, together with mechanical procedures, for all individuals who present supragingival and/or subgingival biofilm, taking into account age, physical and/or psychological limitations, allergies, and other factors.

  1. NMR investigation of water diffusion in different biofilm structures.

    Science.gov (United States)

    Herrling, Maria P; Weisbrodt, Jessica; Kirkland, Catherine M; Williamson, Nathan H; Lackner, Susanne; Codd, Sarah L; Seymour, Joseph D; Guthausen, Gisela; Horn, Harald

    2017-12-01

    Mass transfer in biofilms is determined by diffusion. Different mostly invasive approaches have been used to measure diffusion coefficients in biofilms, however, data on heterogeneous biomass under realistic conditions is still missing. To non-invasively elucidate fluid-structure interactions in complex multispecies biofilms pulsed field gradient-nuclear magnetic resonance (PFG-NMR) was applied to measure the water diffusion in five different types of biomass aggregates: one type of sludge flocs, two types of biofilm, and two types of granules. Data analysis is an important issue when measuring heterogeneous systems and is shown to significantly influence the interpretation and understanding of water diffusion. With respect to numerical reproducibility and physico-chemical interpretation, different data processing methods were explored: (bi)-exponential data analysis and the Γ distribution model. Furthermore, the diffusion coefficient distribution in relation to relaxation was studied by D-T2 maps obtained by 2D inverse Laplace transform (2D ILT). The results show that the effective diffusion coefficients for all biofilm samples ranged from 0.36 to 0.96 relative to that of water. NMR diffusion was linked to biofilm structure (e.g., biomass density, organic and inorganic matter) as observed by magnetic resonance imaging and to traditional biofilm parameters: diffusion was most restricted in granules with compact structures, and fast diffusion was found in heterotrophic biofilms with fluffy structures. The effective diffusion coefficients in the biomass were found to be broadly distributed because of internal biomass heterogeneities, such as gas bubbles, precipitates, and locally changing biofilm densities. Thus, estimations based on biofilm bulk properties in multispecies systems can be overestimated and mean diffusion coefficients might not be sufficiently informative to describe mass transport in biofilms and the near bulk. © 2017 Wiley Periodicals, Inc.

  2. Histophilus somni biofilm formation in cardiopulmonary tissue of the bovine host following respiratory challenge

    DEFF Research Database (Denmark)

    Sandal, Indra; Shao, Jian Q.; Annadata, Satish

    2009-01-01

    cultured with H. somni from heart and lung samples. Transposon mutagenesis of H. somni strain 2336 resulted in the generation of mutants that expressed more or less biofilm. than the parent strain. Six mutants deficient in biofilm formation had an insertion in the gene encoding for a homolog of filamentous...... haemagglutinin (FHA), predicted to be involved in attachment. Thus, this investigation demonstrated that H. somni is capable of forming a biofilm in its natural host, that such a biofilm may be capable of harboring other bovine respiratory disease pathogens, and that the genes responsible for biofilm formation...

  3. Treatment of Oral Biofilms by a D-Enantiomeric Peptide.

    Science.gov (United States)

    Zhang, Tian; Wang, Zhejun; Hancock, Robert E W; de la Fuente-Núñez, César; Haapasalo, Markus

    2016-01-01

    Almost all dental diseases are caused by biofilms that consist of multispecies communities. DJK-5, which is a short D-enantiomeric, protease-resistant peptide with broad-spectrum anti-biofilm activity, was tested for its effect on oral multispecies biofilms. Peptide DJK-5 at 10 μg/mL effectively prevented the growth of these microbes in culture media in a time-dependent manner. In addition to the prevention of growth, peptide DJK-5 completely killed both Streptococcus mutans and Enterococcus faecalis suspended from biofilms after 30 minutes of incubation in liquid culture media. DJK-5 also led to the effective killing of microbes in plaque biofilm. The proportion of bacterial cells killed by 10 μg/mL of DJK-5 was similar after 1 and 3 days, both exceeding 85%. DJK-5 was able to significantly prevent biofilm formation over 3 days (P = 0.000). After 72 hours of exposure, DJK-5 significantly reduced and almost completely prevented plaque biofilm production by more than 90% of biovolume compared to untreated controls (P = 0.000). The proportion of dead biofilm bacteria at the 10 μg/mL DJK-5 concentration was similar for 1- and 3-day-old biofilms, whereby >86% of the bacteria were killed. DJK-5 was also able to kill >79% and >85% of bacteria, respectively, after one-time and three brief treatments of 3-day-old biofilms. The combination of DJK-5 and chlorhexidine showed the best bacterial killing among all treatments, with ~83% and >88% of bacterial cells killed after 1 and 3 minutes, respectively. No significant difference was found in the percentage of biofilm killing amongst three donor plaque samples after DJK-5 treatment. In particular, DJK-5 showed strong performance in inhibiting biofilm development and eradicating pre-formed oral biofilms compared to L-enantiomeric peptide 1018. DJK-5 was very effective against oral biofilms when used alone or combined with chlorhexidine, and may be a promising agent for use in oral anti-biofilm strategies in the future.

  4. Treatment of Oral Biofilms by a D-Enantiomeric Peptide

    Science.gov (United States)

    Zhang, Tian; Wang, Zhejun; Hancock, Robert E. W.; de la Fuente-Núñez, César; Haapasalo, Markus

    2016-01-01

    Almost all dental diseases are caused by biofilms that consist of multispecies communities. DJK-5, which is a short D-enantiomeric, protease-resistant peptide with broad-spectrum anti-biofilm activity, was tested for its effect on oral multispecies biofilms. Peptide DJK-5 at 10 μg/mL effectively prevented the growth of these microbes in culture media in a time-dependent manner. In addition to the prevention of growth, peptide DJK-5 completely killed both Streptococcus mutans and Enterococcus faecalis suspended from biofilms after 30 minutes of incubation in liquid culture media. DJK-5 also led to the effective killing of microbes in plaque biofilm. The proportion of bacterial cells killed by 10 μg/mL of DJK-5 was similar after 1 and 3 days, both exceeding 85%. DJK-5 was able to significantly prevent biofilm formation over 3 days (P = 0.000). After 72 hours of exposure, DJK-5 significantly reduced and almost completely prevented plaque biofilm production by more than 90% of biovolume compared to untreated controls (P = 0.000). The proportion of dead biofilm bacteria at the 10 μg/mL DJK-5 concentration was similar for 1- and 3-day-old biofilms, whereby >86% of the bacteria were killed. DJK-5 was also able to kill >79% and >85% of bacteria, respectively, after one-time and three brief treatments of 3-day-old biofilms. The combination of DJK-5 and chlorhexidine showed the best bacterial killing among all treatments, with ~83% and >88% of bacterial cells killed after 1 and 3 minutes, respectively. No significant difference was found in the percentage of biofilm killing amongst three donor plaque samples after DJK-5 treatment. In particular, DJK-5 showed strong performance in inhibiting biofilm development and eradicating pre-formed oral biofilms compared to L-enantiomeric peptide 1018. DJK-5 was very effective against oral biofilms when used alone or combined with chlorhexidine, and may be a promising agent for use in oral anti-biofilm strategies in the future. PMID

  5. Biofilms on Hospital Shower Hoses: Characterization and ...

    Science.gov (United States)

    Although the source of drinking water used in hospitals is commonly, biofilms on water pipelines are refuge to bacteria that survive different disinfection strategies. Drinking water (DW) biofilms are well known to harbor opportunistic pathogens, however, these biofilm communities remain poorly characterized by culture-independent approaches that circumvent the limitations of conventional monitoring efforts. Hence, the frequency of pathogens in DW biofilms and how biofilm members withstand high doses of disinfectants and/or chlorine residuals in the water supply remain speculative, but directly impact public health. The aim of this study was to characterize the composition of microbial communities growing on five hospital shower hoses using both culture-dependent and culture-independent techniques. Two different sequence-based methods were used to characterize the bacterial fractions: 16S rRNA gene sequencing of bacterial cultures and next generation sequencing of metagenomes. Based on the metagenomic data, we found that Mycobacterium-like species was the abundant bacterial taxa that overlapped among the five samples. We also recovered the draft genome of a novel Mycobacterium species, closely related to opportunistic pathogenic nontuberculous mycobacteria, M. rhodesiae and M. tusciae, in addition to other, less abundant species. In contrast, the cultured fraction was mostly affiliated to Proteobacteria, such as members of the Sphingomonas, Blastomonas and Porph

  6. Medición de cambios cuantitativos de la microbiota subgingival posterior a la remoción de placa bacteriana supragingival Measurement of quantitative changes of the microbiota subgingival after to removal of bacterial plaque supragingival

    OpenAIRE

    C Godoy; C Melej; N Silva

    2010-01-01

    Uno de los campos de interés en el estudio de la microbiología periodontal para muchos investigadores ha sido identificar si es posible que los microorganismos responsables del origen y progresión de la enfermedad periodontal que habitan sobre el margen gingival (supragingival) y bajo este (subgingival) tengan una relación directa que permita mantener interacciones influyentes en el crecimiento y desarrollo de las diferentes especies bacterianas que habitan en los tejidos periodontales. Por l...

  7. Studying bacterial multispecies biofilms

    DEFF Research Database (Denmark)

    Røder, Henriette Lyng; Sørensen, Søren Johannes; Burmølle, Mette

    2016-01-01

    the approaches used to study these complex communities. This review focuses on the establishment of multispecies biofilms in vitro, interspecies interactions in microhabitats, and how to select communities for evaluation. Studies have used different experimental approaches; here we evaluate the benefits......, but the identity and significance of interspecies bacterial interactions is neglected in these analyses. There is therefore an urgent need for bridging the gap between metagenomic analysis and in vitro models suitable for studies of bacterial interactions.Bacterial interactions and coadaptation are important...... at the microscale of complex communities, including biofilms.Studies of multispecies biofilms and the interactions shaping these are conducted in traditional approaches used for single-species biofilms with some adjustments; but a crucial point for consideration is which strains to combine and where these should...

  8. Compaction and relaxation of biofilms

    KAUST Repository

    Valladares Linares, R.

    2015-06-18

    Operation of membrane systems for water treatment can be seriously hampered by biofouling. A better characterization of biofilms in membrane systems and their impact on membrane performance may help to develop effective biofouling control strategies. The objective of this study was to determine the occurrence, extent and timescale of biofilm compaction and relaxation (decompaction), caused by permeate flux variations. The impact of permeate flux changes on biofilm thickness, structure and stiffness was investigated in situ and non-destructively with optical coherence tomography using membrane fouling monitors operated at a constant crossflow velocity of 0.1 m s−1 with permeate production. The permeate flux was varied sequentially from 20 to 60 and back to 20 L m−2 h−1. The study showed that the average biofilm thickness on the membrane decreased after elevating the permeate flux from 20 to 60 L m−2 h−1 while the biofilm thickness increased again after restoring the original flux of 20 L m−2 h−1, indicating the occurrence of biofilm compaction and relaxation. Within a few seconds after the flux change, the biofilm thickness was changed and stabilized, biofilm compaction occurred faster than the relaxation after restoring the original permeate flux. The initial biofilm parameters were not fully reinstated: the biofilm thickness was reduced by 21%, biofilm stiffness had increased and the hydraulic biofilm resistance was elevated by 16%. Biofilm thickness was related to the hydraulic biofilm resistance. Membrane performance losses are related to the biofilm thickness, density and morphology, which are influenced by (variations in) hydraulic conditions. A (temporarily) permeate flux increase caused biofilm compaction, together with membrane performance losses. The impact of biofilms on membrane performance can be influenced (increased and reduced) by operational parameters. The article shows that a (temporary) pressure increase leads to more

  9. Interactions in multispecies biofilms

    DEFF Research Database (Denmark)

    Burmølle, Mette; Ren, Dawei; Bjarnsholt, Thomas

    2014-01-01

    The recent focus on complex bacterial communities has led to the recognition of interactions across species boundaries. This is particularly pronounced in multispecies biofilms, where synergistic interactions impact the bacterial distribution and overall biomass produced. Importantly, in a number...... of settings, the interactions in a multispecies biofilm affect its overall function, physiology, or surroundings, by resulting in enhanced resistance, virulence, or degradation of pollutants, which is of significant importance to human health and activities. The underlying mechanisms causing these synergistic...

  10. Bacterial biofilm in chronic lesions of hidradenitis suppurativa.

    Science.gov (United States)

    Ring, H C; Bay, L; Nilsson, M; Kallenbach, K; Miller, I M; Saunte, D M; Bjarnsholt, T; Tolker-Nielsen, T; Jemec, G B

    2017-04-01

    Chronic nonhealing or recurrent inflammatory lesions, reminiscent of infection but recalcitrant to antibiotic therapy, generally characterize biofilm-driven diseases. Chronic lesions of hidradenitis suppurativa (HS) exhibit several characteristics, which are compatible with well-known biofilm infections. To determine and quantify the potential presence of bacterial aggregates in chronic HS lesions. In 42 consecutive patients with HS suffering from chronic lesions, biopsies were obtained from lesional as well as from perilesional skin. Samples were investigated using peptide nucleic acid-fluorescence in situ hybridization in combination with confocal laser scanning microscopy. In addition, corresponding histopathological analysis on haematoxylin and eosin slides was performed. Biofilms were seen in 67% of the samples of chronic lesions and in 75% of the perilesional samples. The mean diameter of aggregates in lesional skin was significantly greater than in perilesional skin (P = 0·01). Large biofilms (aggregates > 50 μm in diameter) were found in 42% of lesional samples and in only 5% of the perilesional samples (P = 0·009). The majority of the large biofilms were situated in sinus tracts (63%) or in the infundibulum (37%). The majority of the sinus tract samples (73%) contained active bacterial cells, which were associated with inflammation. This study suggests that biofilm formation is associated with inflammation of chronic HS lesions. The aggregates most likely occur as a secondary event, possibly due to predisposing local anatomical changes such as sinus tracts (tunnels), keratinous detritus and dilated hair follicles. © 2016 British Association of Dermatologists.

  11. Comparison of biofilm cell quantification methods for drinking water distribution systems.

    Science.gov (United States)

    Waller, Sharon A; Packman, Aaron I; Hausner, Martina

    2018-01-01

    application in full-scale systems. HPC is a sample and widely applied method that quantifies viable culturable cells. CLSM analysis allows the elimination of experimental variables associated with cell detachment and affords the opportunity to evaluate biofilm components such as extracellular polymeric substances through the addition of specific probes. These two methods can be applied together to assess biofilms known to degrade treated water quality during conveyance in full-scale drinking water treatment systems. The significance of improved biofilm assessment methods for drinking water distribution systems lies in advancing understanding of biofilm growth and control mechanisms that may lead to improved water quality during conveyance and at the tap for greater public health protection. Copyright © 2017 Elsevier B.V. All rights reserved.

  12. The effect of phosphate based glasses on the formation and viability of oral bacterial biofilms

    Science.gov (United States)

    Mulligan, April Miranda

    This study considered the antibacterial activity of a series of soluble phosphate-based glasses (based on the Na2O-CaO-P2O5 glass system) doped with increasing amounts of copper or silver against oral bacterial biofilms. Initially, a variety of phosphate-based glass compositions were produced. The dissolution rate of these glasses was determined, and the information obtained was used to decide which glass compositions would be investigated in future experiments for their antibacterial properties. Selected glass compositions were investigated for their antibacterial activity against Streptococcus sanguis biofilms and oral microcosm biofilms. These biofilms were produced on phosphate-based glass discs using a Constant Depth Film Fermenter (CDFF), which allows the conditions found in the oral cavity to be closely mimicked. Following disc removal from the CDFF, various analytical procedures were carried out. Under conditions designed to mimic the supragingival environment of the oral cavity, fewer viable cells of Streptococcus sanguis were detected on both copper and silver-containing glass discs than on control discs, during the initial stages of the experiments, the greatest reduction occurring on the silver-containing glasses. An increase in viable cell number was observed as the experiments continued. Under the same conditions, copper-containing glasses failed to reduce the viability of microcosm biofilms. Viable cell number was initially reduced on the silver-containing glasses, but by the end of the experiments the viability of microcosm biofilms was significantly similar to those observed on the controls. Attempts to determine the efficacy of silver-containing glasses at reducing the viability of microcosm biofilms, under conditions designed to mimic the subgingival environment of the oral cavity, were subsequently made. Viable cells were not detected on any type of disc, including the control discs. Various reasons for this were postulated. In conclusion, the

  13. Biofilms isolated from washing machines from three continents and their tolerance to a standard detergent.

    Science.gov (United States)

    Gattlen, Jasmin; Amberg, Caroline; Zinn, Manfred; Mauclaire, Laurie

    2010-11-01

    The goal of this comparative study was to investigate biofilm forming microorganisms living in washing machines (WMs). Biofilms were sampled from 11 washing machines from four countries and three continents. Among the 94 isolated strains, 30% were potential human pathogens. Representative strains were selected and biofilm formation was evaluated with the crystal violet (CV) assay. The majority of the WM isolates formed more biofilm than their reference strains. Biofilms of P. putida WM (the largest biofilm producer) were exposed to different concentrations (0.0007-7 g l(-1)) of the standard detergent IEC-A* at 30°C for 30 min and observed with confocal laser scanning microscopy. Using quantitative CVA, P. putida WM biofilm removal required higher detergent concentrations than the type strain. However, for both strains the recommended detergent concentration (7 g l(-1)) was insufficient to completely clean surfaces from cell debris and exopolymeric substances.

  14. Full validation of a method for the determination of drugs of abuse in non-mineralized dental biofilm using liquid chromatography-tandem mass spectrometry and application to postmortem samples.

    Science.gov (United States)

    Henkel, Kerstin; Altenburger, Markus J; Auwärter, Volker; Neukamm, Merja A

    2018-01-01

    Alternative matrices play a major role in postmortem forensic toxicology, especially if common matrices (like body fluids or hair) are not available. Incorporation of illicit and medicinal drugs into non-mineralized dental biofilm (plaque) seems likely but has not been investigated so far. Analysis of plaque could therefore extend the spectrum of potentially used matrices in postmortem toxicology. For this reason, a rapid, simple and sensitive method for the extraction, determination and quantification of ten drugs of abuse from plaque using liquid chromatography-tandem mass spectrometry (LC-MS/MS) was developed and fully validated. Amphetamine, methamphetamine, 3,4-methylenedioxymethamphetamine (MDMA), 3,4-methylenedioxy-N-ethylamphetamine (MDEA), 3,4-methylenedioxyamphetamine (MDA), cocaine, benzoylecgonine, morphine, codeine and 6-acetylmorphine were extracted from 2mg of dried and powdered plaque via ultrasonication with acetonitrile. The extracts were analyzed on a triple-quadrupole linear ion trap mass spectrometer in scheduled multiple reaction monitoring mode (sMRM). The method was fully validated and proved accurate, precise, selective and specific with satisfactory linearity within the calibrated ranges. The lower limit of quantification was 10-15pgmg-1 for all compounds except for MDA (100pgmg-1) and amphetamine (200pgmg-1). The method has been successfully applied to three authentic postmortem samples with known drug history. Amphetamine, MDMA, cocaine, benzoylecgonine, morphine and codeine could be detected in these cases in concentrations ranging from 18pgmg-1 for cocaine to 1400pgmg-1 for amphetamine. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Staphylococcus aureus biofilms: Nemesis of endoscopic sinus surgery.

    Science.gov (United States)

    Singhal, Deepti; Foreman, Andrew; Jervis-Bardy, Joshua; Bardy, Josh-Jervis; Wormald, Peter-John

    2011-07-01

    Chronic rhinosinusitis (CRS) patients with biofilms have persistent postoperative symptoms, ongoing mucosal inflammation, and recurrent infections. Recent evidence suggests that biofilms of differing species confer varying disease profiles in CRS patients. We aimed to prospectively investigate the effects of Staphylococcus aureus, Pseudomonas aeruginosa, Haemophilus influenzae, and fungal biofilms on outcomes following endoscopic sinus surgery (ESS). Prospective blinded study. In this prospective blinded study, 39 patients undergoing ESS for CRS assessed their symptoms preoperatively using internationally accepted standardized symptom scoring systems and quality-of-life measures (10-point visual analog scale, Sino-Nasal Outcome Test-20, global severity of CRS). Their sinonasal mucosa was graded (Lund-Kennedy scale) and extent of radiologic disease on computed tomography scans scored (Lund-McKay scale). Random sinonasal tissue samples were assessed for different bacterial species forming biofilms by using fluorescent in-situ hybridization and confocal laser microscopy. For 12 months after surgery, CRS symptoms, quality of life, and objective evidence of persisting disease were assessed by using the preoperative tools. Different bacterial species combinations were found in 30 of 39 patients; 60% of these 30 biofilms were polymicrobial biofilms and 70% had S aureus biofilms. Preoperative nasendoscopy and radiologic disease severity were significantly worse in patients with multiple biofilms (P = .02 and P = .01, respectively), and they had worse postsurgery mucosal outcomes on endoscopy (P = .01) requiring significantly more postoperative visits (P = .04). Those with S aureus biofilms progressed poorly with their symptom scores and quality-of-life outcomes, with significant differences in nasendoscopy scores (P = .007). S. aureus biofilms play a dominant role in negatively affecting outcomes of ESS with persisting postoperative symptoms, ongoing mucosal inflammation

  16. Characteristics of extracellular polymeric substances of phototrophic biofilms at different aquatic habitats.

    Science.gov (United States)

    Fang, Fang; Lu, Wen-Tao; Shan, Qi; Cao, Jia-Shun

    2014-06-15

    Three different phototrophic biofilms obtained from a natural lake (Sample 1), drinking water plant (Sample 2) and wastewater treatment plant (Sample 3) were investigated. Diatoms and green algae were the dominant algae of three biofilms, and the biomass was highest in biofilm of Sample 2. The three phototrophic biofilms also had variable extracellular polymeric substances (EPS) concentrations and compositions. Total EPS concentration of 14.80 mg/g DW was highest in biofilm of Sample 2, followed by biofilms of Samples 3 and 1 (13.11 and 12.29 mg/g DW). Tightly bound EPS (TB-EPS) were the main fraction, and polysaccharides and protein were the main components of total EPS in all three biofilms. However, the compositions of loosely bound EPS (LB-EPS) and TB-EPS were different in three biofilms. Fourier-transform infrared and fluorescence spectra indicated different structure and compositions of LB-EPS and TB-EPS. These results demonstrated the characteristics of EPS produced by phototrophic biofilms varied and had compact relation to their growth environmental conditions. Copyright © 2014 Elsevier Ltd. All rights reserved.

  17. INFLUENCE OF GENTAMICIN ON ENTEROCOCCI BIOFILM FORMATION

    Directory of Open Access Journals (Sweden)

    Myronenko L.G.

    2017-10-01

    methods using Microsoft Excel 2007 and STATISTICA 6.0 programs. The validity of the differences between the two related samples was assessed by the Wilcoxon test and the Sign test. The effect of the compound was evaluated using biofilm inhibition index (BII, which was calculated according to the formula: [(OD positive control - OD tested / OD positive control] × 100%. Reduction of the OD value by more than 25% in the experiment relative to OD positive control was considered as a positive effect. Results and discussions. Analysis of the results allowed to conclude that gentamicin at concentration of 8 mcg/ml is capable of preventing the formation of biofilms taken in experiments with enterococci. Further increase in the concentration of gentamicin to 64 mcg/ml did not lead to an increase in its activity relative to biofilm formation. When applying gentamicin at concentrations of 8 mcg/ml, 16 mcg/ml, 32 mcg/ml and 64 mcg/ml, the index of inhibition equaled 53,8%, 56,6%, 49,9% and 49,6% respectively. A higher inhibitory effect of gentamicin was identified for the formation of E. faecium biofilms than for E. faecalis ones. Thus, when applying gentamicin at concentrations of 8 mcg/ml, 16 mcg/ml, 32 mcg/ml and 64 mcg/ml for E. faecalis biofilm formation, the inhibition index was equal to 45,5 %, 46,7 %, 49,6 % and 48,5 %, for E. faecium – 54,8 %, 53,5 %, 65,3 % and 60,2 % respectively. One way of facilitating the transportation of biocides through the extracellular matrix of biofilms to the target of action may be the use of so-called penetrators. Polyethylene glycol was used as a penetrator (PNT in our studies. Inhibition index analysis showed a statistically significant increase in the suppressing effect of the combination of gentamicin and PNT on the enterococci biofilm formation compared to the effect of gentamicin without PNT (р<0,05. The inhibition index of gentamicin at concentartions of 8 mcg/ml, 16 mcg/ml, 32 mcg/ml and 64 mcg/ml with PNT amounted to 73,5 %, 74

  18. Investigate Nasal Colonize Staphylococcus Species Biofilm Produced

    Directory of Open Access Journals (Sweden)

    Cemil Demir

    2014-03-01

    Full Text Available Aim: 127 S.aureus and 65 CoNS strains were isolated from patients noses%u2019. To produce a biofilm ability was investigated using three different methods. Slime-positive and negative staphylococcies%u2019 resistance were evaluated against different antibiotics. Material and Method: Swap samples puted 7% blood agar. Staphylococcus aureus and coagulase-negative staphylococci (CoNS isolates biofilm produced ability were investigated using Congo Red Agar (CRA, microplates (MP and Standard Tube (ST methods. In addition to that, presence of antibiotic resistance of the staphylococcal isolates are determined agar disc diffusion method. Results: The rate of biofilm producing Staphylococcus spp strains was found to be 72.4%, 67.7%, and 62.9%, respectively with CRA, MP, and ST tests. There was no significant relationship among the tests (p>0.05. In addition, antibiotic resistance of Staphylococcus spp. against various antibiotics was also determined by the agar disk diffusion method. Resistance rates of biofilm positive (BP Staphylococcus spp for penicilin G, ampicilin, amocycilin/clavulanic acid, tetracyclin, eritromycin, gentamycin, and enrofloxacin 71.7%, 69.7%, 6.2%, 20.7%, 21.4%, 1.4%, and 0.7%, respectively. Resistance rates of biofilm negative (BN spp for 42.6%, 23.4%, 4.3%, 14.9%, 19.1%, 0.0%, 0.0% respectively. All Staphylococcus isolates were found to be susceptible to vancomycin and teicaplonin. Although BP strains antibiotic resistance rates were observed higher than BN strains. But resistance rates were not found statistically significant (p>0.05. Discussion: CRA is the reliablity and specifity method to determine Staphylococcus spp. biofilm produce ability.

  19. BACTERIAL BIOFILMS AND INFECTION (LECTURE

    Directory of Open Access Journals (Sweden)

    Chernjavsky VI

    2013-03-01

    Full Text Available The lecture presents published data on the biofilm – a special from of organization of the microflora of the human body, the role of microbial biofilms in the genesis and development of many common diseases. Different mechanisms of antimicrobial resistance development in biofilm are reviewed in the article

  20. Silver against Pseudomonas aeruginosa biofilms

    DEFF Research Database (Denmark)

    Bjarnsholt, Thomas; Kirketerp-Møller, K.; Kristiansen, S.

    2007-01-01

    bacteria in both the planktonic and biofilm modes of growth. The action of silver on mature in vitro biofilms of Pseudomonas aeruginosa, a primary pathogen of chronic infected wounds, was investigated. The results show that silver is very effective against mature biofilms of P. aeruginosa...

  1. Optimized candidal biofilm microtiter assay

    NARCIS (Netherlands)

    Krom, Bastiaan P.; Cohen, Jesse B.; Feser, Gail E. McElhaney; Cihlar, Ronald L.

    Microtiter based candidal biofilm formation is commonly being used. Here we describe the analysis of factors influencing the development of candidal biofilms such as the coating with serum, growth medium and pH. The data reported here show that optimal candidal biofilm formation is obtained when

  2. Quantifying dental biofilm growth using cross-polarization optical coherence tomography.

    Science.gov (United States)

    Chen, R; Rudney, J; Aparicio, C; Fok, A; Jones, R S

    2012-06-01

    Quantifying the ex vivo growth of complex multispecies dental biofilms using cross-polarization 1310-nm optical coherence tomography (CP-OCT) system was investigated. Bacterial microcosms, which were derived from plaque samples of paediatric subjects, were incubated in a biofilm reactor system containing discs of different dental materials for 72 h with daily sucrose pulsing (5×). CP-OCT analysis of biofilm mass was validated with crystal violet (CV) assays at various growth stages of these complex biofilms. CP-OCT was able to filter out the back-reflected signals of water layers in the hydrated biofilm and allowed for direct biofilm quantification. The overall depth-resolved scattering intensity of the biofilm showed very strong positive correlation with CV assay quantification (Spearman's ρ = 0.92) during the growth phase of the biofilm. CP-OCT was able to quantify the mass of the biofilm by measuring the overall depth-resolved scattering of the biofilm. CP-OCT has the ability to nondestructively monitor biofilm growth and elucidate the growth characteristics of these microcosms on different dental material compositions. © No claim to US Government works. Letters in Applied Microbiology © 2012 The Society for Applied Microbiology.

  3. Meningococcal biofilm formation

    DEFF Research Database (Denmark)

    Lappann, M.; Haagensen, Janus Anders Juul; Claus, H.

    2006-01-01

    We show that in a standardized in vitro flow system unencapsulated variants of genetically diverse lineages of Neisseria meningitidis formed biofilms, that could be maintained for more than 96 h. Biofilm cells were resistant to penicillin, but not to rifampin or ciprofloxacin. For some strains, m......X alleles was identified among genetically diverse meningococcal strains. PilX alleles differed in their propensity to support autoaggregation of cells in suspension, but not in their ability to support microcolony formation within biofilms in the continuous flow system......., microcolony formation within biofilms was observed. Microcolony formation in strain MC58 depended on a functional copy of the pilE gene encoding the pilus subunit pilin, and was associated with twitching of cells. Nevertheless, unpiliated pilE mutants formed biofilms showing that attachment and accumulation...... of cells did not depend on pilus expression. Mutation and complementation analysis revealed that the type IV pilus-associated protein PilX, which was recently shown to mediate interbacterial aggregation, indirectly supported microcolony formation by contributing to pilus expression. A large number of Pil...

  4. Photosynthetic performance of phototrophic biofilms in extreme acidic environments.

    Science.gov (United States)

    Souza-Egipsy, Virginia; Altamirano, María; Amils, Ricardo; Aguilera, Angeles

    2011-08-01

    Photosynthesis versus irradiance curves and their associated photosynthetic parameters from different phototrophic biofilms isolated from an extreme acidic environment (Río Tinto, SW, Spain) were studied in order to relate them to their species composition and the physicochemical characteristics of their respective sampling locations. The results indicated that the biofilms are low light acclimated showing a photoinhibition model; only floating communities of filamentous algae showed a light saturation model. Thus, all the biofilms analysed showed photoinhibition over 60 µmol photon m(-2) s(-1) except in the case of Zygnemopsis sp. sample, which showed a light-saturated photosynthesis model under irradiations higher that 200 µmol photon m(-2) s(-1). The highest values of compensation light intensity (I(c)) were showed also by Zygnemosis sp. biofilm (c. 40 µmol photon m(-2) s(-1)), followed by Euglena mutabilis and Chlorella sp. samples (c. 20 µmol photon m(-2) s(-1)). The diatom sample showed the lowest I(c) values (c. 5 µmol photon m(-2) s(-1)). As far as we know this is the first attempt to determine the photosynthetic activity of low pH and heavy metal tolerant phototrophic biofilms, which may give light in the understanding of the ecological importance of these biofilms for the maintenance of the primary production of these extreme and unique ecosystems. © 2011 Society for Applied Microbiology and Blackwell Publishing Ltd.

  5. Biofilm formation by Rhodococcus equi and putative association with macrolide resistance

    Directory of Open Access Journals (Sweden)

    Letícia T. Gressler

    2015-10-01

    Full Text Available Abstract: Rhodococcus equi is a facultative intracellular pathogen, which cause severe pyogranulomatous pneumonia in foals and tuberculosis-like lesions in humans. Its ability to form biofilm was described in strains isolated from chronic diseases associated to treatment failures in humans. This study aimed to verify the biofilm formation by 113 R. equi isolated from equine samples (clinical and fecal using two different methods (biofilm-culturing with and without additional glucose and epifluorescence microscopy. We also aimed to determine the efficacy of azithromycin, clarithromycin and erythromycin on R. equi in established biofilm. We found 80.5% (26/41 and 63% (58/72 biofilm-positive isolates, in fecal and clinical samples, respectively. The additional glucose increased the biofilm formation by R. equi fecal samples, but not by clinical samples. The antimicrobials tested herein were not able to eradicate R. equi in biofilm even at higher concentrations. This is the first study showing the biofilm formation by R. equi isolated from equine samples. Our findings indicate that R. equi biofilm-producers may be more resistant to the antimicrobials evaluated. Further studies are warranted to test this hypothesis.

  6. Microtiter dish biofilm formation assay.

    Science.gov (United States)

    O'Toole, George A

    2011-01-30

    Biofilms are communities of microbes attached to surfaces, which can be found in medical, industrial and natural settings. In fact, life in a biofilm probably represents the predominate mode of growth for microbes in most environments. Mature biofilms have a few distinct characteristics. Biofilm microbes are typically surrounded by an extracellular matrix that provides structure and protection to the community. Microbes growing in a biofilm also have a characteristic architecture generally comprised of macrocolonies (containing thousands of cells) surrounded by fluid-filled channels. Biofilm-grown microbes are also notorious for their resistance to a range of antimicrobial agents including clinically relevant antibiotics. The microtiter dish assay is an important tool for the study of the early stages in biofilm formation, and has been applied primarily for the study of bacterial biofilms, although this assay has also been used to study fungal biofilm formation. Because this assay uses static, batch-growth conditions, it does not allow for the formation of the mature biofilms typically associated with flow cell systems. However, the assay has been effective at identifying many factors required for initiation of biofilm formation (i.e, flagella, pili, adhesins, enzymes involved in cyclic-di-GMP binding and metabolism) and well as genes involved in extracellular polysaccharide production. Furthermore, published work indicates that biofilms grown in microtiter dishes do develop some properties of mature biofilms, such a antibiotic tolerance and resistance to immune system effectors. This simple microtiter dish assay allows for the formation of a biofilm on the wall and/or bottom of a microtiter dish. The high throughput nature of the assay makes it useful for genetic screens, as well as testing biofilm formation by multiple strains under various growth conditions. Variants of this assay have been used to assess early biofilm formation for a wide variety of microbes

  7. The presence of biofilm forming microorganisms on hydrotherapy equipment and facilities.

    Science.gov (United States)

    Jarząb, Natalia; Walczak, Maciej

    2017-10-01

    Hydrotherapy equipment provides a perfect environment for the formation and growth of microbial biofilms. Biofilms may reduce the microbiological cleanliness of hydrotherapy equipment and harbour opportunistic pathogens and pathogenic bacteria. The aims of this study were to investigate the ability of microorganisms that colonize hydrotherapy equipment to form biofilms, and to assess the influence of temperature and nutrients on the rate of biofilm formation. Surface swab samples were collected from the whirlpool baths, inhalation equipment and submerged surfaces of a brine pool at the spa center in Ciechocinek, Poland. We isolated and identified microorganisms from the swab samples and measured their ability to form biofilms. Biofilm formation was observed at a range of temperatures, in both nutrient-deficient and nutrient-rich environments. We isolated and identified microorganisms which are known to form biofilms on medical devices (e.g. Stenotrophomonas maltophilia). All isolates were classified as opportunistic pathogens, which can cause infections in humans with weakened immunity systems. All isolates showed the ability to form biofilms in the laboratory conditions. The potential for biofilm formation was higher in the presence of added nutrients. In addition, the hydrolytic activity of the biofilm was connected with the presence of nutrients.

  8. Membrane biofilm communities in full-scale membrane bioreactors are not randomly assembled and consist of a core microbiome

    KAUST Repository

    Matar, Gerald Kamil

    2017-06-21

    Finding efficient biofouling control strategies requires a better understanding of the microbial ecology of membrane biofilm communities in membrane bioreactors (MBRs). Studies that characterized the membrane biofilm communities in lab-and pilot-scale MBRs are numerous, yet similar studies in full-scale MBRs are limited. Also, most of these studies have characterized the mature biofilm communities with very few studies addressing early biofilm communities. In this study, five full-scale MBRs located in Seattle (Washington, U.S.A.) were selected to address two questions concerning membrane biofilm communities (early and mature): (i) Is the assembly of biofilm communities (early and mature) the result of random immigration of species from the source community (i.e. activated sludge)? and (ii) Is there a core membrane biofilm community in full-scale MBRs? Membrane biofilm (early and mature) and activated sludge (AS) samples were collected from the five MBRs, and 16S rRNA gene sequencing was applied to investigate the bacterial communities of AS and membrane biofilms (early and mature). Alpha and beta diversity measures revealed clear differences in the bacterial community structure between the AS and biofilm (early and mature) samples in the five full-scale MBRs. These differences were mainly due to the presence of large number of unique but rare operational taxonomic units (∼13% of total reads in each MBR) in each sample. In contrast, a high percentage (∼87% of total reads in each MBR) of sequence reads was shared between AS and biofilm samples in each MBR, and these shared sequence reads mainly belong to the dominant taxa in these samples. Despite the large fraction of shared sequence reads between AS and biofilm samples, simulated biofilm communities from random sampling of the respective AS community revealed that biofilm communities differed significantly from the random assemblages (P < 0.001 for each MBR), indicating that the biofilm communities (early

  9. Membrane biofilm communities in full-scale membrane bioreactors are not randomly assembled and consist of a core microbiome.

    Science.gov (United States)

    Matar, Gerald K; Bagchi, Samik; Zhang, Kai; Oerther, Daniel B; Saikaly, Pascal E

    2017-10-15

    Finding efficient biofouling control strategies requires a better understanding of the microbial ecology of membrane biofilm communities in membrane bioreactors (MBRs). Studies that characterized the membrane biofilm communities in lab-and pilot-scale MBRs are numerous, yet similar studies in full-scale MBRs are limited. Also, most of these studies have characterized the mature biofilm communities with very few studies addressing early biofilm communities. In this study, five full-scale MBRs located in Seattle (Washington, U.S.A.) were selected to address two questions concerning membrane biofilm communities (early and mature): (i) Is the assembly of biofilm communities (early and mature) the result of random immigration of species from the source community (i.e. activated sludge)? and (ii) Is there a core membrane biofilm community in full-scale MBRs? Membrane biofilm (early and mature) and activated sludge (AS) samples were collected from the five MBRs, and 16S rRNA gene sequencing was applied to investigate the bacterial communities of AS and membrane biofilms (early and mature). Alpha and beta diversity measures revealed clear differences in the bacterial community structure between the AS and biofilm (early and mature) samples in the five full-scale MBRs. These differences were mainly due to the presence of large number of unique but rare operational taxonomic units (∼13% of total reads in each MBR) in each sample. In contrast, a high percentage (∼87% of total reads in each MBR) of sequence reads was shared between AS and biofilm samples in each MBR, and these shared sequence reads mainly belong to the dominant taxa in these samples. Despite the large fraction of shared sequence reads between AS and biofilm samples, simulated biofilm communities from random sampling of the respective AS community revealed that biofilm communities differed significantly from the random assemblages (P < 0.001 for each MBR), indicating that the biofilm communities (early

  10. Comparison between two visible biofilm indices in the primary dentition.

    Science.gov (United States)

    dos Santos, Ana Paula Pires; Soviero, Vera Mendes

    2006-01-01

    The aim of this study was to compare two visible biofilm indices in the primary dentition. The sample consisted of 90 children of both sexes, aged up to 4 years old outpatients of the University Hospital of the Rio de Janeiro State University. A single examiner, aided by an assistant, performed the children's dental examination for biofilm assessment. A simplified visible biofilm index (BF1), which classifies biofilm as absent, thin or thick, in anterior and/or posterior teeth, and provides a score for the patient and not for each tooth, was compared to a conventional visible biofilm index, the visible plaque index, (BF2), which classifies biofilm as absent or present and provides scores for three surfaces of each tooth. A statistically significant association and a strong positive correlation between BF1 and BF2 was found (Kruskal-Wallis p biofilm index is feasible in the primary dentition as it showed similar findings when compared to a conventional one, besides being more practical and quicker.

  11. Bacterial biofilm and associated infections.

    Science.gov (United States)

    Jamal, Muhsin; Ahmad, Wisal; Andleeb, Saadia; Jalil, Fazal; Imran, Muhammad; Nawaz, Muhammad Asif; Hussain, Tahir; Ali, Muhammad; Rafiq, Muhammad; Kamil, Muhammad Atif

    2018-01-01

    Microscopic entities, microorganisms that drastically affect human health need to be thoroughly investigated. A biofilm is an architectural colony of microorganisms, within a matrix of extracellular polymeric substance that they produce. Biofilm contains microbial cells adherent to one-another and to a static surface (living or non-living). Bacterial biofilms are usually pathogenic in nature and can cause nosocomial infections. The National Institutes of Health (NIH) revealed that among all microbial and chronic infections, 65% and 80%, respectively, are associated with biofilm formation. The process of biofilm formation consists of many steps, starting with attachment to a living or non-living surface that will lead to formation of micro-colony, giving rise to three-dimensional structures and ending up, after maturation, with detachment. During formation of biofilm several species of bacteria communicate with one another, employing quorum sensing. In general, bacterial biofilms show resistance against human immune system, as well as against antibiotics. Health related concerns speak loud due to the biofilm potential to cause diseases, utilizing both device-related and non-device-related infections. In summary, the understanding of bacterial biofilm is important to manage and/or to eradicate biofilm-related diseases. The current review is, therefore, an effort to encompass the current concepts in biofilm formation and its implications in human health and disease. Copyright © 2017. Published by Elsevier Taiwan LLC.

  12. Bacterial biofilm and associated infections

    Directory of Open Access Journals (Sweden)

    Muhsin Jamal

    2018-01-01

    Full Text Available Microscopic entities, microorganisms that drastically affect human health need to be thoroughly investigated. A biofilm is an architectural colony of microorganisms, within a matrix of extracellular polymeric substance that they produce. Biofilm contains microbial cells adherent to one-another and to a static surface (living or non-living. Bacterial biofilms are usually pathogenic in nature and can cause nosocomial infections. The National Institutes of Health (NIH revealed that among all microbial and chronic infections, 65% and 80%, respectively, are associated with biofilm formation. The process of biofilm formation consists of many steps, starting with attachment to a living or non-living surface that will lead to formation of micro-colony, giving rise to three-dimensional structures and ending up, after maturation, with detachment. During formation of biofilm several species of bacteria communicate with one another, employing quorum sensing. In general, bacterial biofilms show resistance against human immune system, as well as against antibiotics. Health related concerns speak loud due to the biofilm potential to cause diseases, utilizing both device-related and non-device-related infections. In summary, the understanding of bacterial biofilm is important to manage and/or to eradicate biofilm-related diseases. The current review is, therefore, an effort to encompass the current concepts in biofilm formation and its implications in human health and disease.

  13. Manipulatiaon of Biofilm Microbial Ecology

    Energy Technology Data Exchange (ETDEWEB)

    Burkhalter, R.; Macnaughton, S.J.; Palmer, R.J.; Smith, C.A.; Whitaker, K.W.; White, D.C.; Zinn, M.; kirkegaard, R.

    1998-08-09

    The Biofilm mode of growth provides such significant advantages to the members of the consortium that most organisms in important habitats are found in biofilms. The study of factors that allow manipulation of biofilm microbes in the biofilm growth state requires that reproducible biofilms by generated. The most effective monitoring of biofilm formation, succession and desquamation is with on-line monitoring of microbial biofilms with flowcell for direct observation. The biofilm growth state incorporates a second important factor, the heterogeneity in the distribution in time and space of the component members of the biofilm consortium. This heterogeneity is reflected not only in the cellular distribution but in the metabolic activity within a population of cells. Activity and cellular distribution can be mapped in four dimensions with confocal microscopy, and function can be ascertained by genetically manipulated reporter functions for specific genes or by vital stains. The methodology for understanding the microbial ecology of biofilms is now much more readily available and the capacity to manipulate biofilms is becoming an important feature of biotechnology.

  14. Manipulation of Biofilm Microbial Ecology

    Energy Technology Data Exchange (ETDEWEB)

    White, D.C.; Palmer, R.J., Jr.; Zinn, M.; Smith, C.A.; Burkhalter, R.; Macnaughton, S.J.; Whitaker, K.W.; Kirkegaard, R.D.

    1998-08-15

    The biofilm mode of growth provides such significant advantages to the members of the consortium that most organisms in important habitats are found in biofilms. The study of factors that allow manipulation of biofilm microbes in the biofilm growth state requires that reproducible biofilms be generated. The most effective monitoring of biofilm formation, succession and desaturation is with on-line monitoring of microbial biofilms with flowcell for direct observation. The biofilm growth state incorporates a second important factor, the heterogeneity in distribution in time and space of the component members of the biofilm consortium. This heterogeneity is reflected not only in the cellular distribution but in the metabolic activity within a population of cells. Activity and cellular distribution can be mapped in four dimensions with confocal microscopy, and function can be ascertained by genetically manipulated reporter functions for specific genes or by vital stains. The methodology for understanding the microbial ecology of biofilms is now much more readily available and the capacity to manipulate biofilms is becoming an important feature of biotechnology.

  15. Biofilm formation on abiotic surfaces

    DEFF Research Database (Denmark)

    Tang, Lone

    2011-01-01

    Bacteria can attach to any surface in contact with water and proliferate into complex communities enclosed in an adhesive matrix, these communities are called biofilms. The matrix makes the biofilm difficult to remove by physical means, and bacteria in biofilm can survive treatment with many...... antibiotics, disinfectants and cleaning agents. Biofilms are therefore very difficult to eradicate, and an attractive approach to limit biofilm formation is to reduce bacterial adhesion. In this thesis it was shown that lowering the surface roughness had a greater effect on bacterial retention compared....... The ability to form biofilms, the amount of eDNA produced, and the importance of eDNA for biofilm formation or stability did not correlate and varied from strain to strain. Finally, a method was developed for immobilization of living bacteria for analysis by atomic force microscopy (AFM). AFM is used...

  16. Critical review on biofilm methods.

    Science.gov (United States)

    Azeredo, Joana; Azevedo, Nuno F; Briandet, Romain; Cerca, Nuno; Coenye, Tom; Costa, Ana Rita; Desvaux, Mickaël; Di Bonaventura, Giovanni; Hébraud, Michel; Jaglic, Zoran; Kačániová, Miroslava; Knøchel, Susanne; Lourenço, Anália; Mergulhão, Filipe; Meyer, Rikke Louise; Nychas, George; Simões, Manuel; Tresse, Odile; Sternberg, Claus

    2017-05-01

    Biofilms are widespread in nature and constitute an important strategy implemented by microorganisms to survive in sometimes harsh environmental conditions. They can be beneficial or have a negative impact particularly when formed in industrial settings or on medical devices. As such, research into the formation and elimination of biofilms is important for many disciplines. Several new methodologies have been recently developed for, or adapted to, biofilm studies that have contributed to deeper knowledge on biofilm physiology, structure and composition. In this review, traditional and cutting-edge methods to study biofilm biomass, viability, structure, composition and physiology are addressed. Moreover, as there is a lack of consensus among the diversity of techniques used to grow and study biofilms. This review intends to remedy this, by giving a critical perspective, highlighting the advantages and limitations of several methods. Accordingly, this review aims at helping scientists in finding the most appropriate and up-to-date methods to study their biofilms.

  17. Interfacial Electrochemical Electron Transfer Processes in Bacterial Biofilm Environments on Au(111)

    DEFF Research Database (Denmark)

    Hu, Yifan; Zhang, Jingdong; Ulstrup, Jens

    2010-01-01

    ](3-/4-) (both negatively charged and no growth inhibition) were distorted from planar diffusion behavior on bare Au(111)-electrode surfaces toward spherical diffusion behavior on S. mutans biofilm covered Au(111)-electrode surfaces. DNAase teatment of the biofilm covered Au(111)-electrode surface partly...... was followed by sampling at given times, drying the samples naturally, and imaging. The electrochemical investigations were based on single-crystal Au(111)-electrode surfaces to exclude polycrystallinity as a cause of inhomogeneous voltammetric broadening on the biofilm covered electrode surfaces. The redox......)(6)](3+2+) (positively charged, biofilm growth inhibitor) and [Co(terpy)(2)](3+2+) (positively charged, no biofilm growth inhibition) displayed fully reversible CV on biofilm covered electrodes, almost indistinguishable from CV at bare Au(111)-electrode surfaces. In comparison, CVs of [Fe(CN)(6)](3-/4-) and [IrCl6...

  18. Fungi, Water Supply and Biofilms.

    Science.gov (United States)

    Kauffmann-Lacroix, Catherine; Costa, Damien; Imbert, Christine

    Even though it has been studied for many years, water-related infectious risk still exists in both care and community environments due to the possible presence of numerous microorganisms such as bacteria, fungi and protists. People can be exposed directly to these microorganisms either through aerosols and water, after ingestion, inhalation, skin contact and entry through mucosal membranes, or indirectly usually due to pre-treatment of some medical devices. Species belonging to genera such as Aspergillus, Penicillium, Pseudallesheria, Fusarium, Cuninghamella, Mucor and in some particular cases Candida have been isolated in water from health facilities and their presence is particularly related to the unavoidable formation of a polymicrobial biofilm in waterlines. Fungi isolation methods are based on water filtration combined with conventional microbiology cultures and/or molecular approaches; unfortunately, these are still poorly standardized. Moreover, due to inappropriate culture media and inadequate sampling volumes, the current standardized methods used for bacterial research are not suitable for fungal search. In order to prevent water-related fungal risk, health facilities have implemented measures such as ultraviolet radiation to treat the input network, continuous chemical treatment, chemical or thermal shock treatments, or microfiltration at points of use. This article aims to provide an overview of fungal colonization of water (especially in hospitals), involvement of biofilms that develop in waterlines and application of preventive strategies.

  19. Identification of early microbial colonizers in human dental biofilm.

    Science.gov (United States)

    Li, J; Helmerhorst, E J; Leone, C W; Troxler, R F; Yaskell, T; Haffajee, A D; Socransky, S S; Oppenheim, F G

    2004-01-01

    To elucidate the first colonizers within in vivo dental biofilm and to establish potential population shifts that occur during the early phases of biofilm formation. A 'checkerboard' DNA-DNA hybridization assay was employed to identify 40 different bacterial strains. Dental biofilm samples were collected from 15 healthy subjects, 0, 2, 4 and 6 h after tooth cleaning and the composition of these samples was compared with that of whole saliva collected from the same individuals. The bacterial distribution in biofilm samples was distinct from that in saliva, confirming the selectivity of the adhesion process. In the very early stages, the predominant tooth colonizers were found to be Actinomyces species. The relative proportion of streptococci, in particular Streptococcus mitis and S. oralis, increased at the expense of Actinomyces species between 2 and 6 h while the absolute level of Actinomyces remained unaltered. Periodontal pathogens such as Tannerella forsythensis(Bacteroides forsythus), Porphyromonas gingivalis and Treponema denticola as well as Actinobacillus actinomycetemcomitans were present in extremely low levels at all the examined time intervals in this healthy group of subjects. The data provide a detailed insight into the bacterial population shifts occurring within the first few hours of biofilm formation and show that the early colonizers of the tooth surface predominantly consist of beneficial micro-organisms. The early colonizers of dental plaque are of great importance in the succession stages of biofilm formation and its overall effect on the oral health of the host.

  20. Adenoid Reservoir for Pathogenic Biofilm Bacteria▿

    Science.gov (United States)

    Nistico, L.; Kreft, R.; Gieseke, A.; Coticchia, J. M.; Burrows, A.; Khampang, P.; Liu, Y.; Kerschner, J. E.; Post, J. C.; Lonergan, S.; Sampath, R.; Hu, F. Z.; Ehrlich, G. D.; Stoodley, P.; Hall-Stoodley, L.

    2011-01-01

    Biofilms of pathogenic bacteria are present on the middle ear mucosa of children with chronic otitis media (COM) and may contribute to the persistence of pathogens and the recalcitrance of COM to antibiotic treatment. Controlled studies indicate that adenoidectomy is effective in the treatment of COM, suggesting that the adenoids may act as a reservoir for COM pathogens. To investigate the bacterial community in the adenoid, samples were obtained from 35 children undergoing adenoidectomy for chronic OM or obstructive sleep apnea. We used a novel, culture-independent molecular diagnostic methodology, followed by confocal microscopy, to investigate the in situ distribution and organization of pathogens in the adenoids to determine whether pathogenic bacteria exhibited criteria characteristic of biofilms. The Ibis T5000 Universal Biosensor System was used to interrogate the extent of the microbial diversity within adenoid biopsy specimens. Using a suite of 16 broad-range bacterial primers, we demonstrated that adenoids from both diagnostic groups were colonized with polymicrobial biofilms. Haemophilus influenzae was present in more adenoids from the COM group (P = 0.005), but there was no significant difference between the two patient groups for Streptococcus pneumoniae or Staphylococcus aureus. Fluorescence in situ hybridization, lectin binding, and the use of antibodies specific for host epithelial cells demonstrated that pathogens were aggregated, surrounded by a carbohydrate matrix, and localized on and within the epithelial cell surface, which is consistent with criteria for bacterial biofilms. PMID:21307211

  1. Biofilm roughness determines Cryptosporidium parvum retention in environmental biofilms.

    Science.gov (United States)

    DiCesare, E A Wolyniak; Hargreaves, B R; Jellison, K L

    2012-06-01

    The genus Cryptosporidium is a group of waterborne protozoan parasites that have been implicated in significant outbreaks of gastrointestinal infections throughout the world. Biofilms trap these pathogens and can contaminate water supplies through subsequent release. Biofilm microbial assemblages were collected seasonally from three streams in eastern Pennsylvania and used to grow biofilms in laboratory microcosms. Daily oocyst counts in the influx and efflux flow allowed the calculation of daily oocyst retention in the biofilm. Following the removal of oocysts from the influx water, oocyst attachment to the biofilm declined to an equilibrium state within 5 days that was sustained for at least 25 days. Varying the oocyst loading rate for the system showed that biofilm retention could be saturated, suggesting that discrete binding sites determined the maximum number of oocysts retained. Oocyst retention varied seasonally but was consistent across all three sites; however, seasonal oocyst retention was not consistent across years at the same site. No correlation between oocyst attachment and any measured water quality parameter was found. However, oocyst retention was strongly correlated with biofilm surface roughness and roughness varied among seasons and across years. We hypothesize that biofilm roughness and oocyst retention are dependent on environmentally driven changes in the biofilm community rather than directly on water quality conditions. It is important to understand oocyst transport dynamics to reduce risks of human infection. Better understanding of factors controlling biofilm retention of oocysts should improve our understanding of oocyst transport at different scales.

  2. Development and pyrosequencing analysis of an in-vitro oral biofilm model.

    Science.gov (United States)

    Kistler, James O; Pesaro, Manuel; Wade, William G

    2015-02-10

    Dental caries and periodontal disease are the commonest bacterial diseases of man and can result in tooth loss. The principal method of prevention is the mechanical removal of dental plaque augmented by active agents incorporated into toothpastes and mouthrinses. In-vitro assays that include complex oral bacterial biofilms are required to accurately predict the efficacy of novel active agents in vivo. The aim of this study was to develop an oral biofilm model using the Calgary biofilm device (CBD) seeded with a natural saliva inoculum and analysed by next generation sequencing. The specific objectives were to determine the reproducibility and stability of the model by comparing the composition of the biofilms over time derived from (i) the same volunteers at different time points, and (ii) different panels of volunteers. Pyrosequencing yielded 280,093 sequences with a mean length of 432 bases after filtering. A mean of 320 and 250 OTUs were detected in pooled saliva and biofilm samples, respectively. Principal coordinates analysis (PCoA) plots based on community membership and structure showed that replicate biofilm samples were highly similar and clustered together. In addition, there were no significant differences between biofilms derived from the same panel at different times using analysis of molecular variance (AMOVA). There were significant differences between biofilms from different panels (AMOVA, P < 0.002). PCoA revealed that there was a shift in biofilm composition between seven and 14 days (AMOVA, P < 0.001). Veillonella parvula, Veillonella atypica/dispar/parvula and Peptostreptococcus stomatis were the predominant OTUs detected in seven-day biofilms, whilst Prevotella oralis, V. parvula and Streptococcus constellatus were predominant in 14-day biofilms. Diverse oral biofilms were successfully grown and maintained using the CBD. Biofilms derived from the same panel of volunteers were highly reproducible. This model could be used to screen both

  3. Achromobacter Species Isolated from Cystic Fibrosis Patients Reveal Distinctly Different Biofilm Morphotypes

    DEFF Research Database (Denmark)

    Nielsen, Signe M; Nørskov-Lauritsen, Niels; Bjarnsholt, Thomas

    2016-01-01

    findings were visualized in sputum samples from cystic fibrosis patients using an Achromobacter specific peptide nucleic acid fluorescence in situ hybridization (PNA-FISH) probe, confirming the presence of Achromobacter biofilms in the CF lung. High antibiotic tolerance was associated with the biofilm......Achromobacter species have attracted attention as emerging pathogens in cystic fibrosis. The clinical significance of Achromobacter infection is not yet fully elucidated; however, their intrinsic resistance to antimicrobials and ability to form biofilms renders them capable of establishing long...

  4. Proteus mirabilis biofilm - Qualitative and quantitative colorimetric methods-based evaluation

    OpenAIRE

    Kwiecinska-Pir?g, Joanna; Bogiel, Tomasz; Skowron, Krzysztof; Wieckowska, Ewa; Gospodarek, Eugenia

    2015-01-01

    Proteus mirabilis strains ability to form biofilm is a current topic of a number of research worldwide. In this study the biofilm formation of P. mirabilis strains derived from urine of the catheterized and non-catheterized patients has been investigated. A total number of 39 P. mirabilis strains isolated from the urine samples of the patients of dr Antoni Jurasz University Hospital No. 1 in Bydgoszcz clinics between 2011 and 2012 was used. Biofilm formation was evaluated using two independen...

  5. [Biofilms in otolaryngology].

    Science.gov (United States)

    Mena Viveros, Nicolás

    2014-01-01

    According to the National Institute of Health of the USA, «more than 60% of all microbial infections are caused by biofilms».'This can surprise us, but it is enough to consider that common infections like those of the genito-urinary tract, infections produced by catheters, middle ear infections in children, the formation of dental plaque and gingivitis are caused by biofilms, for this statement to seem more realistic. At present this is one of the subjects of great interest within medicine, particularly in otolaryngology. Bacteria have traditionally been considered to be in a free state without evident organization, partly perhaps by the ease of studying them in this form. Nevertheless, the reality is that, in nature, the great majority of these germs form complex colonies adhered to surfaces, colonies that have received the name of biofilms. These biofilms are more common than previously thought and almost all of the people have been in contact with them in the form of infections in the teeth or humid, slippery areas. New treatments that can eradicate them are currently being investigated. Copyright © 2012 Elsevier España, S.L. All rights reserved.

  6. Orthopaedic biofilm infections.

    Science.gov (United States)

    Stoodley, Paul; Ehrlich, Garth D; Sedghizadeh, Parish P; Hall-Stoodley, Luanne; Baratz, Mark E; Altman, Daniel T; Sotereanos, Nicholas G; Costerton, John William; Demeo, Patrick

    2011-11-01

    A recent paradigm shift in microbiology affects orthopaedic surgery and most other medical and dental disciplines because more than 65% of bacterial infections treated by clinicians in the developed world are now known to be caused by organisms growing in biofilms. These slime-enclosed communities of bacteria are inherently resistant to host defenses and to conventional antibacterial therapy, and these device-related and other chronic bacterial infections are unaffected by the vaccines and antibiotics that have virtually eliminated acute infections caused by planktonic (floating) bacteria. We examine the lessons that can be learned, within this biofilm paradigm, by the study of problems (e.g. non-culturability) shared by all biofilm infections and by the study of new therapeutic options aimed specifically at sessile bacteria in biofilms. Orthopaedic surgery has deduced some of the therapeutic strategies based on assiduous attention to patient outcomes, but much can still be learned by attention to modern research in related disciplines in medicine and dentistry. These perceptions will lead to practical improvements in the detection, management, and treatment of infections in orthopaedic surgery.

  7. Molecular Techniques Revealed Highly Diverse Microbial Communities in Natural Marine Biofilms on Polystyrene Dishes for Invertebrate Larval Settlement

    KAUST Repository

    Lee, On On

    2014-01-09

    Biofilm microbial communities play an important role in the larval settlement response of marine invertebrates. However, the underlying mechanism has yet to be resolved, mainly because of the uncertainties in characterizing members in the communities using traditional 16S rRNA gene-based molecular methods and in identifying the chemical signals involved. In this study, pyrosequencing was used to characterize the bacterial communities in intertidal and subtidal marine biofilms developed during two seasons. We revealed highly diverse biofilm bacterial communities that varied with season and tidal level. Over 3,000 operational taxonomic units with estimates of up to 8,000 species were recovered in a biofilm sample, which is by far the highest number recorded in subtropical marine biofilms. Nineteen phyla were found, of which Cyanobacteria and Proteobacteria were the most dominant one in the intertidal and subtidal biofilms, respectively. Apart from these, Actinobacteria, Bacteroidetes, and Planctomycetes were the major groups recovered in both intertidal and subtidal biofilms, although their relative abundance varied among samples. Full-length 16S rRNA gene clone libraries were constructed for the four biofilm samples and showed similar bacterial compositions at the phylum level to those revealed by pyrosequencing. Laboratory assays confirmed that cyrids of the barnacle Balanus amphitrite preferred to settle on the intertidal rather than subtidal biofilms. This preference was independent of the biofilm bacterial density or biomass but was probably related to the biofilm community structure, particularly, the Proteobacterial and Cyanobacterial groups. © 2014 Springer Science+Business Media New York.

  8. Biofilms from a Brazilian water distribution system include filamentous fungi.

    Science.gov (United States)

    Siqueira, V M; Oliveira, H M B; Santos, C; Paterson, R R M; Gusmão, N B; Lima, N

    2013-03-01

    Filamentous fungi in drinking water can block water pipes, can cause organoleptic biodeterioration, and are a source of pathogens. There are increasing reports of the involvement of the organisms in biofilms. This present study describes a sampling device that can be inserted directly into pipes within water distribution systems, allowing biofilm formation in situ. Calcofluor White M2R staining and fluorescent in situ hybridization with morphological analyses using epifluorescent microscopy were used to analyse biofilms for filamentous fungi, permitting direct observation of the fungi. DAPI (4',6-diamidino-2-phenylindole) was applied to detect bacteria. Filamentous fungi were detected in biofilms after 6 months on coupons exposed to raw water, decanted water and at the entrance of the water distribution system. Algae, yeast, and bacteria were also observed. The role of filamentous fungi requires further investigations.

  9. Supragingival biofilm control and systemic inflammation in patients with type 2 diabetes mellitus

    Directory of Open Access Journals (Sweden)

    Hilana Paula Carillo ARTESE

    2015-01-01

    Full Text Available The objective of this study was to evaluate the effect of strict supragingival biofilm control on serum inflammatory markers and on periodontal clinical parameters in type 2 diabetes mellitus (T2DM patients with chronic severe periodontitis. Twenty-four individuals with T2DM and periodontitis were randomly allocated to two treatment groups. The supragingival therapy group (ST, n = 12 received supragingival scaling, whereas the intensive therapy group (IT, n = 12 underwent supra- and subgingival scaling, as well as root planing. Patients from both groups received professional oral hygiene instructions every month. Data regarding visible plaque index (VPI, gingival bleeding index (GBI, bleeding on probing (BOP, probing pocket depth (PPD, clinical attachment level (CAL, serum levels of interleukin (IL-6, IL-17A, IL-8, tumor necrosis factor α (TNF-α, monocyte chemoattractant protein (MCP-1 enzyme-linked immunosorbent assay (ELISA, and glycated hemoglobin (HbA1c levels were obtained at baseline and at 6 months post-therapy. Both therapies resulted in the improvement of almost all clinical periodontal parameters (p 0.05, between the two periods. However, MCP-1 levels were significantly reduced in both the ST (p = 0.034 and the IT (p = 0.016 groups, whereas the serum IL-6 levels were significantly reduced only in the IT group (p = 0.001. Strict control of supragingival biofilm has a limited effect on systemic inflammatory markers, and a moderate effect on periodontal clinical parameters.

  10. Visualizing the dental biofilm matrix by means of fluorescence lectin-binding analysis.

    Science.gov (United States)

    Tawakoli, Pune N; Neu, Thomas R; Busck, Mette M; Kuhlicke, Ute; Schramm, Andreas; Attin, Thomas; Wiedemeier, Daniel B; Schlafer, Sebastian

    2017-01-01

    The extracellular matrix is a poorly studied, yet important component of dental biofilms. Fluorescence lectin-binding analysis (FLBA) is a powerful tool to characterize glycoconjugates in the biofilm matrix. This study aimed to systematically investigate the ability of 75 fluorescently labeled lectins to visualize and quantify extracellular glycoconjugates in dental biofilms. Lectin binding was screened on pooled supragingival biofilm samples collected from 76 subjects using confocal microscopy. FLBA was then performed with 10 selected lectins on biofilms grown in situ for 48 h in the absence of sucrose. For five lectins that proved particularly suitable, stained biovolumes were quantified and correlated to the bacterial composition of the biofilms. Additionally, combinations of up to three differently labeled lectins were tested. Of the 10 lectins, five bound particularly well in 48-h-biofilms: Aleuria aurantia (AAL), Calystega sepiem (Calsepa), Lycopersicon esculentum (LEA), Morniga-G (MNA-G) and Helix pomatia (HPA). No significant correlation between the binding of specific lectins and bacterial composition was found. Fluorescently labeled lectins enable the visualization of glycoconjugates in the dental biofilm matrix. The characterization and quantification of glycoconjugates in dental biofilms require a combination of several lectins. For 48-h-biofilms grown in absence of sucrose, AAL, Calsepa, HPA, LEA, and MNA-G are recommendable.

  11. Biofilm formation in surface and drinking water distribution systems in Mafikeng, South Africa

    Directory of Open Access Journals (Sweden)

    Suma George Mulamattathil

    2014-11-01

    Full Text Available Poor quality source water and poorly treated reused wastewater may result in poor quality drinking water that has a higher potential to form biofilms. A biofilm is a group of microorganisms which adhere to a surface. We investigated biofilm growth in the drinking water distribution systems in the Mafikeng area, in the North- West Province of South Africa. Analysis was conducted to determine the presence of faecal coliforms, total coliforms, Pseudomonas spp. and Aeromonas spp. in the biofilms. Biofilms were grown on a device that contained copper and galvanised steel coupons. A mini tap filter – a point-of-use treatment device which can be used at a single faucet – was also used to collect samples. Scanning electron microscopy demonstrated that multi-species biofilms developed on all the coupons as well as on the point-of-use filters. Galvanised steel and carbon filters had the highest density of biofilm. Total coliforms, faecal coliforms and Pseudomonas spp. were isolated from raw water biofilm coupons only. Aeromonas spp. and Pseudomonas spp. were isolated from filters. The susceptibility of selected isolates was tested against 11 antibiotics of clinical interest. The most prevalent antibiotic resistance phenotype observed was KF-AP-C-E-OT-K-TM-A. The presence of virulence genes was determined using the polymerase chain reaction. These results indicate that bacteria present in the water have the ability to colonise as biofilms and drinking water biofilms may be a reservoir for opportunistic bacteria including Pseudomonas and Aeromonas species.

  12. Are those bugs reflective? Non-destructive biofilm imaging with white light interferometry

    Energy Technology Data Exchange (ETDEWEB)

    Larimer, Curtis J.; Brann, Michelle R.; Suter, Jonathan D.; Bonheyo, George T.; Addleman, Raymond S.

    2016-08-28

    White light interferometry (WLI) is not typically used to image bacterial biofilms that are immersed in water because there is insufficient refractive index contrast to induce reflection from the biofilm’s interface. The soft structure and water-like bulk properties of hydrated biofilms make them difficult to characterize in situ by any means, especially in a non-destructive manner. Here we describe a new method for measuring and monitoring the thickness and topology of live biofilms using a WLI microscope. A microfluidic system was used to create a reflective interface on the surface of biofilms. Live biofilm samples were monitored non-destructively over time. The method enables surface metrology measurements (roughness, surface area) and a novel approach to measuring thickness of the thin hydrated biofilms. Increase in surface roughness preceded observable increase in biofilm thickness, indicating that this measure may be used to predict future development of biofilms. We have also developed a flow cell that enables WLI biofilm imaging in a dynamic environment. We have used this flow cell to observe changes in biofilm structure in response to changes in environmental conditions - flow velocity, availability of nutrients, and presence of biocides.

  13. Fluoride in saliva and dental biofilm after 1500 and 5000 ppm fluoride exposure.

    Science.gov (United States)

    Staun Larsen, Line; Baelum, Vibeke; Tenuta, Livia Maria Andaló; Richards, Alan; Nyvad, Bente

    2017-09-01

    The aim of this randomized, double-blind, crossover study was to measure fluoride in saliva and 7-day-old biofilm fluid and biofilm solids after rinsing three times per day for 3 weeks with 0, 1500, or 5000 ppm fluoride (NaF). Following the 3-week wash-in/wash-out period, including 1 week of biofilm accumulation, saliva and biofilm samples were collected from 12 participants immediately before (background fluoride), and 10, 30, and 60 min after a single rinse. Biofilm samples were separated into fluid and solids, and samples were analyzed using a fluoride electrode (microanalysis). The background fluoride concentration was statistically significantly higher in the 5000 compared to the 1500 ppm F rinse group in all three compartments (22.3 and 8.1 μM in saliva, 126.8 and 58.5 μM in biofilm fluid, and 10,940 and 4837 μmol/kg in biofilm solids). The 1-h fluoride accumulation for the 5000 ppm F rinse was higher than for the 1500 ppm F rinse in all three compartments, although not statistically significant for saliva and biofilm solids. Regular exposure to 5000 ppm fluoride elevates background fluoride concentrations in saliva, biofilm fluid, and biofilm solids compared to 1500 ppm fluoride. Increasing the fluoride concentration almost 3.5 times (from 1500 to 5000 ppm) only elevates the background fluoride concentrations in saliva, biofilm fluid, and biofilm solids twofold. Even though fluoride toothpaste may be diluted by saliva, the results of the present study indicate that use of 5000 ppm fluoride toothpaste might lead to improved caries control.

  14. Biofilm Induced Tolerance Towards Antimicrobial Peptides

    DEFF Research Database (Denmark)

    Folkesson, Anders; Haagensen, Janus Anders Juul; Zampaloni, Claudia

    2008-01-01

    Increased tolerance to antimicrobial agents is thought to be an important feature of microbes growing in biofilms. We address the question of how biofilm organization affects antibiotic susceptibility. We established Escherichia coli biofilms with differential structural organization due...

  15. Association of biofilm production with colonization among clinical isolates of Acinetobacter baumannii.

    Science.gov (United States)

    Ryu, Seong Yeol; Baek, Won-Ki; Kim, Hyun Ah

    2017-03-01

    The pathogen Acinetobacter baumannii is increasingly causing healthcare-associated infections worldwide, particularly in intensive care units. Biofilm formation, a factor contributing to the virulence of A. baumannii, is associated with long-term persistence in hospital environments. The present study investigates the clinical impact of biofilm production on colonization and acquisition after patient admission. Forty-nine A. baumannii isolates were obtained between August and November 2013 from Keimyung University Dongsan Medical Center, Daegu, Korea. All isolates were obtained from sputum samples of new patients infected or colonized by A. baumannii. The microtiter plate assay was used to determine biofilm formation. Twenty-four A. baumannii isolates (48%) demonstrated enhanced biofilm formation capacity than that of the standard A. baumannii strain (ATCC 19606). All isolates were resistant to carbapenem, 38 isolates (77%) were collected from patients in an intensive care unit, and 47 isolates (95%) were from patients who had been exposed to antibiotics in the previous month. The median duration of colonization was longer for biofilm-producing isolates than that of the biofilm non-biofilm producing isolates (18 days vs. 12 days, p < 0.05). Simultaneous colonization with other bacteria was more common for biofilm-producing isolates than that for the non-biofilm producing isolates. The most prevalent co-colonizing bacteria was Staphylococcus aureus. Biofilm-producing isolates seem to colonize the respiratory tract for longer durations than the non-biofilm producing isolates. During colonization, biofilm producers promote co-colonization by other bacteria, particularly S. aureus. Additional research is required to determine possible links between biofilm formation and nosocomial infection.

  16. Standardization and Classification of In vitro Biofilm Formation by Clinical Isolates of Staphylococcus aureus.

    Science.gov (United States)

    Singh, Ashish Kumar; Prakash, Pradyot; Achra, Arvind; Singh, Gyan Prakash; Das, Arghya; Singh, Rakesh Kumar

    2017-01-01

    Staphylococcus aureus is Gram-positive bacterium commonly associated with nosocomial infections. The development of biofilm exhibiting drug resistance especially in foreign body associated infections has enabled the bacterium to draw considerable attention. However, till date, consensus guidelines for in vitro biofilm quantitation and categorization criterion for the bacterial isolates based on biofilm-forming capacity are lacking. Therefore, it was intended to standardize in vitro biofilm formation by clinical isolates of S. aureus and then to classify them on the basis of their biofilm-forming capacity. A study was conducted for biofilm quantitation by tissue culture plate (TCP) assay employing 61 strains of S. aureus isolated from clinical samples during May 2015- December 2015 wherein several factors influencing the biofilm formation were optimized. Therefore, it was intended to propose a biofilm classification criteria based on the standard deviation multiples of the control differentiating them into non, low, medium, and high biofilm formers. Brain-heart infusion broth was found to be more effective in biofilm formation compared to trypticase soy broth. Heat fixation was more effective than chemical fixation. Although, individually, glucose, sucrose, and sodium chloride (NaCl) had no significant effect on biofilm formation, a statistically significant increase in absorbance was observed after using the supplement mix consisting of 222.2 mM glucose, 116.9 mM sucrose, and 1000 mM NaCl (P= 0.037). The present study puts forth a standardized in vitro TCP assay for biofilm biomass quantitation and categorization criteria for clinical isolates of S. aureus based on their biofilm-forming capacity. The proposed in vitro technique may be further evaluated for its usefulness in the management of persistent infections caused by the bacterium.

  17. Standardization and classification of In vitro biofilm formation by clinical isolates of Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    Ashish Kumar Singh

    2017-01-01

    Full Text Available Background: Staphylococcus aureus is Gram-positive bacterium commonly associated with nosocomial infections. The development of biofilm exhibiting drug resistance especially in foreign body associated infections has enabled the bacterium to draw considerable attention. However, till date, consensus guidelines for in vitro biofilm quantitation and categorization criterion for the bacterial isolates based on biofilm-forming capacity are lacking. Therefore, it was intended to standardize in vitro biofilm formation by clinical isolates of S. aureus and then to classify them on the basis of their biofilm-forming capacity. Materials and Methods: A study was conducted for biofilm quantitation by tissue culture plate (TCP assay employing 61 strains of S. aureus isolated from clinical samples during May 2015– December 2015 wherein several factors influencing the biofilm formation were optimized. Therefore, it was intended to propose a biofilm classification criteria based on the standard deviation multiples of the control differentiating them into non, low, medium, and high biofilm formers. Results: Brain-heart infusion broth was found to be more effective in biofilm formation compared to trypticase soy broth. Heat fixation was more effective than chemical fixation. Although, individually, glucose, sucrose, and sodium chloride (NaCl had no significant effect on biofilm formation, a statistically significant increase in absorbance was observed after using the supplement mix consisting of 222.2 mM glucose, 116.9 mM sucrose, and 1000 mM NaCl (P = 0.037. Conclusions: The present study puts forth a standardized in vitro TCP assay for biofilm biomass quantitation and categorization criteria for clinical isolates of S. aureus based on their biofilm-forming capacity. The proposed in vitro technique may be further evaluated for its usefulness in the management of persistent infections caused by the bacterium.

  18. Critical review on biofilm methods

    DEFF Research Database (Denmark)

    Azeredo, Joana; F. Azevedo, Nuno; Briandet, Romain

    2017-01-01

    Biofilms are widespread in nature and constitute an important strategy implemented by microorganisms to survive in sometimes harsh environmental conditions. They can be beneficial or have a negative impact particularly when formed in industrial settings or on medical devices. As such, research...... into the formation and elimination of biofilms is important for many disciplines. Several new methodologies have been recently developed for, or adapted to, biofilm studies that have contributed to deeper knowledge on biofilm physiology, structure and composition. In this review, traditional and cutting-edge methods...... to study biofilm biomass, viability, structure, composition and physiology are addressed. Moreover, as there is a lack of consensus among the diversity of techniques used to grow and study biofilms. This review intends to remedy this, by giving a critical perspective, highlighting the advantages...

  19. New Technologies for Studying Biofilms

    Science.gov (United States)

    FRANKLIN, MICHAEL J.; CHANG, CONNIE; AKIYAMA, TATSUYA; BOTHNER, BRIAN

    2016-01-01

    Bacteria have traditionally been studied as single-cell organisms. In laboratory settings, aerobic bacteria are usually cultured in aerated flasks, where the cells are considered essentially homogenous. However, in many natural environments, bacteria and other microorganisms grow in mixed communities, often associated with surfaces. Biofilms are comprised of surface-associated microorganisms, their extracellular matrix material, and environmental chemicals that have adsorbed to the bacteria or their matrix material. While this definition of a biofilm is fairly simple, biofilms are complex and dynamic. Our understanding of the activities of individual biofilm cells and whole biofilm systems has developed rapidly, due in part to advances in molecular, analytical, and imaging tools and the miniaturization of tools designed to characterize biofilms at the enzyme level, cellular level, and systems level. PMID:26350329

  20. Synergistic Interactions in Multispecies Biofilms

    DEFF Research Database (Denmark)

    Ren, Dawei

    bacterial species, the study to elucidate the impact of interaction networks on the multispecies biofilms in natural ecosystems, especially in soil, is still at an early stage. The diverse patterns of interactions within the mixed communities as well as the predatorprey relationship between protozoa...... or Paenibacillus amylolyticus as well as in a four-species biofilm. The strongest change in expression profile was observed in the dual-species biofilms of X. retroflexus and P. amylolyticus, while a distinct expression pattern (non-linear response) was detected in the four-species biofilm, indicating...... in integrated communities in multispecies biofilm. However, these conclusions are based on the assumption that this flagellate predator prefers surface attached cells which needs to be confirmed by further studies. Horizontal gene transfer by conjugation occurs more efficiently in biofilms. The connection...

  1. Antibiotic treatment of biofilm infections

    DEFF Research Database (Denmark)

    Ciofu, Oana; Rojo-Molinero, Estrella; Macià, María D.

    2017-01-01

    Bacterial biofilms are associated with a wide range of infections, from those related to exogenous devices, such as catheters or prosthetic joints, to chronic tissue infections such as those occurring in the lungs of cystic fibrosis patients. Biofilms are recalcitrant to antibiotic treatment due...... to multiple tolerance mechanisms (phenotypic resistance). This causes persistence of biofilm infections in spite of antibiotic exposure which predisposes to antibiotic resistance development (genetic resistance). Understanding the interplay between phenotypic and genetic resistance mechanisms acting...... on biofilms, as well as appreciating the diversity of environmental conditions of biofilm infections which influence the effect of antibiotics are required in order to optimize the antibiotic treatment of biofilm infections. Here, we review the current knowledge on phenotypic and genetic resistance...

  2. Electrochemical biofilm control: A review

    Science.gov (United States)

    Sultana, Sujala T; Babauta, Jerome T; Beyenal, Haluk

    2015-01-01

    One of the methods of controlling biofilms that has widely been discussed in the literature is to apply a potential or electrical current to a metal surface on which the biofilm is growing. Although electrochemical biofilm control has been studied for decades, the literature is often conflicting, as is detailed in this review. The goals of this review are to (1) present the current status of knowledge regarding electrochemical biofilm control, (2) establish a basis for a fundamental definition of electrochemical biofilm control and requirements for studying it, (3) discuss current proposed mechanisms, and (4) introduce future directions in the field. It is expected that the review will provide researchers with guidelines on comparing data sets across the literature and generating comparable data sets. The authors believe that, with the correct design, electrochemical biofilm control has great potential for industrial use. PMID:26592420

  3. Field emission scanning electron microscopy of biofilm-growing bacteria involved in nosocomial infections.

    Science.gov (United States)

    Vuotto, Claudia; Donelli, Gianfranco

    2014-01-01

    Scanning electron microscopy (SEM) provides useful information on the shape, size, and localization within the biofilm of single bacteria as well as on the steps of biofilm formation process, on bacterial interactions, and on production of extracellular polymeric substances.When biofilms are constituted by microbial species involved in health care-associated infections, information provided by SEM can be fruitfully used not only for basic researches but also for diagnostic purposes.The protocols currently used in our laboratory for biofilm investigation by SEM are reported here. Particularly, the procedures to fix, dehydrate, and metalize in vitro-developed biofilms or ex vivo clinical specimens colonized by biofilm-growing microorganisms are described as well as the advantages of the observation of these samples by field emission scanning electron microscopy.

  4. Characterization, Microbial Community Structure, and Pathogen Occurrence in Urban Faucet Biofilms in South China.

    Science.gov (United States)

    Lin, Huirong; Zhang, Shuting; Gong, Song; Zhang, Shenghua; Yu, Xin

    2015-01-01

    The composition and microbial community structure of the drinking water system biofilms were investigated using microstructure analysis and 454 pyrosequencing technique in Xiamen city, southeast of China. SEM (scanning electron microscope) results showed different features of biofilm morphology in different fields of PVC pipe. Extracellular matrix material and sparse populations of bacteria (mainly rod-shaped and coccoid) were observed. CLSM (confocal laser scanning microscope) revealed different distributions of attached cells, extracellular proteins, α-polysaccharides, and β-polysaccharides. The biofilms had complex bacterial compositions. Differences in bacteria diversity and composition from different tap materials and ages were observed. Proteobacteria was the common and predominant group in all biofilms samples. Some potential pathogens (Legionellales, Enterobacteriales, Chromatiales, and Pseudomonadales) and corrosive microorganisms were also found in the biofilms. This study provides the information of characterization and visualization of the drinking water biofilms matrix, as well as the microbial community structure and opportunistic pathogens occurrence.

  5. Extracellular DNA contributes to dental biofilm formation: An ex vivo study

    DEFF Research Database (Denmark)

    Schlafer, Sebastian; Meyer, Rikke Louise; Dige, Irene

    2016-01-01

    The extracellular matrix of dental biofilms plays an important role during caries development. It increases the mechanical stability of the biofilm, it prevents desiccation, it serves as a reservoir for nutrients and it contributes to the long-term preservation of acidic microenvironments. Research......, and that the enzymatic removal of extracellular DNA might be used as a therapeutic approach to biofilm diseases. Here, we investigate the effect of treatment with DNase I (100 Kunitz) on in vivo grown young dental biofilms. A total of 300 biofilm samples were grown on glass slabs placed on acrylic splints for 2.5, 5, 7...... results make a strong case for an increased research focus on extracellular DNA in dental biofilms and might pave the way for new, non-bactericidal therapeutic approaches to caries control based on DNase treatment....

  6. Characterization, Microbial Community Structure, and Pathogen Occurrence in Urban Faucet Biofilms in South China

    Directory of Open Access Journals (Sweden)

    Huirong Lin

    2015-01-01

    Full Text Available The composition and microbial community structure of the drinking water system biofilms were investigated using microstructure analysis and 454 pyrosequencing technique in Xiamen city, southeast of China. SEM (scanning electron microscope results showed different features of biofilm morphology in different fields of PVC pipe. Extracellular matrix material and sparse populations of bacteria (mainly rod-shaped and coccoid were observed. CLSM (confocal laser scanning microscope revealed different distributions of attached cells, extracellular proteins, α-polysaccharides, and β-polysaccharides. The biofilms had complex bacterial compositions. Differences in bacteria diversity and composition from different tap materials and ages were observed. Proteobacteria was the common and predominant group in all biofilms samples. Some potential pathogens (Legionellales, Enterobacteriales, Chromatiales, and Pseudomonadales and corrosive microorganisms were also found in the biofilms. This study provides the information of characterization and visualization of the drinking water biofilms matrix, as well as the microbial community structure and opportunistic pathogens occurrence.

  7. Quantitative optical coherence microscopy for the in situ investigation of the biofilm

    Science.gov (United States)

    Meleppat, Ratheesh Kumar; Shearwood, Christopher; Keey, Seah Leong; Matham, Murukeshan Vadakke

    2016-12-01

    This paper explores the potential of optical coherence microscopy (OCM) for the in situ monitoring of biofilm growth. The quantitative imaging of the early developmental biology of a representative biofilm, Klebsiella pneumonia (KP-1), was performed using a swept source-based Fourier domain OCM system. The growth dynamics of the KP-1 biofilms and their transient response under perturbation was investigated using the enface visualization of microcolonies and their spatial localization. Furthermore, the optical density (OD) and planar density of the biofilms are calculated using an OCM technique and compared with OD and colony forming units measured using standard procedures via the sampling of the flow-cell effluent.

  8. Biofilm: A dental microbial infection

    OpenAIRE

    Saini, Rajiv; Saini, Santosh; Sharma, Sugandha

    2011-01-01

    Recent advances in research technology have allowed researchers to study bacteria in their natural environment. Dental biofilm forms via an ordered sequence of events, resulting in structured and functionally organized species rich microbial community and modern molecular biological techniques have identified about 1000 different bacterial species in the dental biofilm, twice as many as can be cultured. Sites for biofilm formation include all kinds of surfaces: natural materials above and bel...

  9. Therapeutic Strategies Targeting Cariogenic Biofilm Microenvironment

    National Research Council Canada - National Science Library

    Liu, Y; Ren, Z; Hwang, G; Koo, H

    2018-01-01

    Cariogenic biofilms are highly structured microbial communities embedded in an extracellular matrix, a multifunctional scaffold that is essential for the existence of the biofilm lifestyle and full...

  10. Bioremediation of hydrocarbons contaminating sewage effluent using man-made biofilms: effects of some variables.

    Science.gov (United States)

    Al-Mailem, D M; Kansour, M K; Radwan, S S

    2014-11-01

    Biofilm samples were established on glass slides by submerging them in oil-free and oil-containing sewage effluent for a month. In batch cultures, such biofilms were effective in removing crude oil, pure n-hexadecane, and pure phenanthrene contaminating sewage effluent. The amounts of the removed hydrocarbons increased with increasing biofilm surface area exposed to the effluent. On the other hand, addition of the reducing agent thioglycollate dramatically inhibited the hydrocarbon bioremediation potential of the biofilms. The same biofilm samples removed contaminating hydrocarbons effectively in three successive batch bioremediation cycles but started to become less effective in the cycles thereafter, apparently due to mechanical biofilm loss during successive transfers. As major hydrocarbonoclastic bacteria, the biofilms harbored species belonging to the genera Pseudomonas, Microvirga, Zavarzinia, Mycobacterium, Microbacterium, Stenotrophomonas, Gordonia, Bosea, Sphingobium, Brachybacterium, and others. The nitrogen fixer Azospirillum brasilense and the microalga Ochromonas distigma were also present; they seemed to enrich the biofilms, with nitrogenous compounds and molecular oxygen, respectively, which are known to enhance microbiological hydrocarbon degradation. It was concluded that man-made biofilms based upon sewage microflora are promising tools for bioremediation of hydrocarbons contaminating sewage effluent.

  11. Antibiotic treatment of biofilm infections.

    Science.gov (United States)

    Ciofu, Oana; Rojo-Molinero, Estrella; Macià, María D; Oliver, Antonio

    2017-04-01

    Bacterial biofilms are associated with a wide range of infections, from those related to exogenous devices, such as catheters or prosthetic joints, to chronic tissue infections such as those occurring in the lungs of cystic fibrosis patients. Biofilms are recalcitrant to antibiotic treatment due to multiple tolerance mechanisms (phenotypic resistance). This causes persistence of biofilm infections in spite of antibiotic exposure which predisposes to antibiotic resistance development (genetic resistance). Understanding the interplay between phenotypic and genetic resistance mechanisms acting on biofilms, as well as appreciating the diversity of environmental conditions of biofilm infections which influence the effect of antibiotics are required in order to optimize the antibiotic treatment of biofilm infections. Here, we review the current knowledge on phenotypic and genetic resistance in biofilms and describe the potential strategies for the antibiotic treatment of biofilm infections. Of note is the optimization of PK/PD parameters in biofilms, high-dose topical treatments, combined and sequential/alternate therapies or the use antibiotic adjuvants. © 2017 APMIS. Published by John Wiley & Sons Ltd.

  12. Understanding Biofilms in Chronic Sinusitis.

    Science.gov (United States)

    Tajudeen, Bobby A; Schwartz, Joseph S; Palmer, James N

    2016-02-01

    Chronic sinusitis is a burdensome disease that has substantial individual and societal impact. Although great advances in medical and surgical therapies have been made, some patients continue to have recalcitrant infections. Microbial biofilms have been implicated as a cause of recalcitrant chronic sinusitis, and recent studies have tried to better understand the pathogenesis of chronic sinusitis as it relates to microbial biofilms. Here, we provide an overview of biofilms in chronic sinusitis with emphasis on pathogenesis, treatment, and future directions. In addition, recent evidence is presented, elucidating the role of bitter taste receptors as a possible key factor leading to biofilm formation.

  13. Biofilm and Dental Biomaterials

    Directory of Open Access Journals (Sweden)

    Marit Øilo

    2015-05-01

    Full Text Available All treatment involving the use of biomaterials in the body can affect the host in positive or negative ways. The microbiological environment in the oral cavity is affected by the composition and shape of the biomaterials used for oral restorations. This may impair the patients’ oral health and sometimes their general health as well. Many factors determine the composition of the microbiota and the formation of biofilm in relation to biomaterials such as, surface roughness, surface energy and chemical composition, This paper aims to give an overview of the scientific literature regarding the association between the chemical, mechanical and physical properties of dental biomaterials and oral biofilm formation, with emphasis on current research and future perspectives.

  14. Biofilm and dental biomaterials

    OpenAIRE

    Øilo, Marit; Bakken, Vidar

    2015-01-01

    All treatment involving the use of biomaterials in the body can affect the host in positive or negative ways. The microbiological environment in the oral cavity is affected by the composition and shape of the biomaterials used for oral restorations. This may impair the patients’ oral health and sometimes their general health as well. Many factors determine the composition of the microbiota and the formation of biofilm in relation to biomaterials such as, surface roughness, surface energy and ...

  15. Microbial community stratification in Membrane-Aerated Biofilm Reactors for Completely Autotrophic Nitrogen Removal

    DEFF Research Database (Denmark)

    Pellicer i Nàcher, Carles; Ruscalleda, Maël; Terada, Akihiko

    1028 hollow fiber membranes (200/280 µm inner/outer diameter) covered homogeneously by biofilm. Samples (low, middle and upper part of the biofilm) were collected, fixed, embedded in OCT compound for cryosection and later Fluorescence In-Situ Hybridization (FISH). Emphasis was put on elucidating...

  16. Biofilm production among Staphylococcus epidermidis strains isolated from healthy people

    Directory of Open Access Journals (Sweden)

    Fateh Rahimi

    2016-09-01

    Full Text Available Introduction: Staphylococcus epidermidis is well documented as a nosocomial pathogen causing biofilm in patients and healthy people. The aim of this study was to analyze the biofilm formation of S. epidermidis strains isolated from healthy people during 2013-2014. Materials and methods: Totally 200 healthy people were selected and the sampling was carried out from arm, armpit and axillary area using sterile swaps. Swaps were transferred to thiogylcollate broth and then cultured on mannitol salt agar plates. Isolates were identified at the species level using biochemical tests. Potential of biofilm formation of strains was measured using congo red agar plate and microtiter plate tests. Genes involved in biofilm formation, icaA and icaD, were detected using PCR. Results: Totally 104 S. epidermidis strains were isolated from healthy people. Amongst these, 66 (63% and 38 (37% strains were positive and negative for biofilm formation, respectively. icaA and icaD genes were detected in 100% of strains. Discussion and conclusion: Prevalence of biofilm producing S. epidermidis isolates among healthy people indicating their colonization with hospital strains. Prevalence of such strains is  urgent for public health.

  17. The effects of silver nanoparticles on intact wastewater biofilms

    Directory of Open Access Journals (Sweden)

    Zhiya eSheng

    2015-07-01

    Full Text Available Silver nanoparticles (Ag-NPs have strong antibacterial properties, which may adversely affect biological wastewater treatment processes. To determine the overall effect, intact biofilm samples were collected from the rotating biological contactor (RBC at the local wastewater treatment plant and treated with 200 mg Ag/L Ag-NPs for 24 h. The biofilm uptake of Ag-NPs was monitored with transmission electron microscopy (TEM. Forty-five min after Ag-NP application, Ag-NPs were seen in the biofilm extracellular polymeric substances (EPS. After 24 h, Ag-NPs had entered certain microbial cells, while other cells contained no observable Ag-NPs. Some cells were dying after the uptake of Ag-NPs. However, there was no significant reduction in cultivable bacteria in the biofilms, based on heterotrophic plate counts (HPC. While this may indicate that wastewater biofilms are highly resistant to Ag-NPs, the HPC represents only a small portion of the total microbial population. To further investigate the effects of Ag-NPs, a GeoChip microarray was used to directly detect changes in the functional gene structure of the microbial community in the biofilm. A clear decrease (34.6% decrease in gene number in gene diversity was evident in the GeoChip analysis. However, the complete loss of any specific gene was rare. Some gene families present in both treated and untreated biofilms. However, this doesn’t necessarily mean that there was no change in these families. Signal intensity decreased in certain variants in each family while other variants increased to compensate the effects of Ag-NPs. The results indicate that Ag-NP treatment decreased microbial community diversity but did not significantly affect the microbial community function. This provides direct evidence for the functional redundancy of microbial community in engineered ecosystems such as wastewater biofilms.

  18. Activity of disinfectants and biofilm production of Corynebacterium pseudotuberculosis

    Directory of Open Access Journals (Sweden)

    Maria da C.A. Sá

    2013-11-01

    Full Text Available To verify the occurrence of caseous lymphadenitis in sheep and goats on farms of Pernambuco, Brazil, and in animals slaughtered in two Brazilian cities (Petrolina/PE and Juazeiro/BA, and to characterize the susceptibility profile of Corynebacterium pseudotuberculosis to disinfectants and antimicrobials, and its relationship with biofilm production were the objectives of this study. 398 samples were tested for sensitivity to antimicrobial drugs, disinfectants, and biofilm production. Among the 108 samples collected on the properties, 75% were positive for C. pseudotuberculosis. Slaughterhouse samples indicated an occurrence of caseous lymphadenitis in 15.66% and 6.31% for animals slaughtered in Petrolina and Juazeiro respectively. With respect to antimicrobials, the sensitivity obtained was 100% for florfenicol and tetracycline; 99.25% for enrofloxacin, ciprofloxacin and lincomycin; 98.99% for cephalothin; 98.74% for norfloxacin and sulfazotrim; 97.74% for gentamicin; 94.22% for ampicillin; 91.71% for amoxicillin; 91.21% for penicillin G; 89.19% for neomycin and 0% for novobiocin. In analyzes with disinfectants, the efficiency for chlorhexidine was 100%, 97.20% for quaternary ammonium, 87.40% for chlorine and 84.40% for iodine. 75% of the isolates were weak or non-biofilm producers. For the consolidated biofilm, found that iodine decreased biofilm formation in 13 isolates and quaternary ammonia in 11 isolates. The reduction of the biofilm formation was observed for iodine and quaternary ammonium in consolidated biofilm formation in 33% and 28% of the isolates, respectively. The results of this study highlight the importance of establishing measures to prevent and control the disease.

  19. Molecular methods for biofilms

    KAUST Repository

    Ferrera, Isabel

    2014-08-30

    at the same time and to compare bacterial communities among different samples or in a single sample after certain treatments. DGGE, T-RFLP and ARISA share similar steps but require different materials and equipment. The three methods involve (i) sampling of the biofilms; (ii) DNA extraction and quantification; and (iii) PCR using specific primers. Metagenomics: This chapter focuses classical and next-generation metagenomics methods. These are limited to bacterial artificial chromosome (BAC) and Fosmid libraries and Sanger and next-generation 454 sequencing, as these methods are currently the most frequently used in research. The chapter discusses the special handling of deoxyribonucleic acid (DNA) needed to construct BAC and Fosmid libraries from marine water samples. It also briefly addresses the related topics of library archiving, databasing, and screening. The chapter provides a high-level overview of the special handling methods required to prepare DNA for BAC library construction. No special handling is needed for Fosmid library construction.

  20. Staphylococcus aureus biofilms: recent developments in biofilm dispersal.

    Science.gov (United States)

    Lister, Jessica L; Horswill, Alexander R

    2014-01-01

    Staphylococcus aureus is a major cause of nosocomial and community-acquired infections and represents a significant burden on the healthcare system. S. aureus attachment to medical implants and host tissue, and the establishment of a mature biofilm, play an important role in the persistence of chronic infections. The formation of a biofilm, and encasement of cells in a polymer-based matrix, decreases the susceptibility to antimicrobials and immune defenses, making these infections difficult to eradicate. During infection, dispersal of cells from the biofilm can result in spread to secondary sites and worsening of the infection. In this review, we discuss the current understanding of the pathways behind biofilm dispersal in S. aureus, with a focus on enzymatic and newly described broad-spectrum dispersal mechanisms. Additionally, we explore potential applications of dispersal in the treatment of biofilm-mediated infections.

  1. Interaction of Nanoparticles with Biofilms

    Science.gov (United States)

    In this work we have studied the interaction and adsorption of engineered nanoparticles such as TiO2, ZnO, CeO2 , and carbon nanotubes with biofilms. Biofilm is an extracellular polymeric substance coating comprised of living material and it is an aggregation of bacteria, algae, ...

  2. Biofilms: Community Behavior by Bacteria

    Indian Academy of Sciences (India)

    IAS Admin

    It has been found that waste water treated by the biofilm method (activated sludge) is very effective. Biofilms can also be used to 'eat up' petroleum and other oil products. There is also the concept of microbial leaching. For example, low grade ore is mildly acidified to encourage the growth of bacteria which oxidize the ore to ...

  3. Highlights in pathogenic fungal biofilms.

    Science.gov (United States)

    Sardi, Janaina De Cássia Orlandi; Pitangui, Nayla De Souza; Rodríguez-Arellanes, Gabriela; Taylor, Maria Lucia; Fusco-Almeida, Ana Maria; Mendes-Giannini, Maria José Soares

    2014-01-01

    A wide variety of fungi have demonstrated the ability to colonize surfaces and form biofilms. Most studies on fungal biofilms have focused on Candida albicans and more recently, several authors have reported the involvement of other genera of yeasts and Candida species, as well as of filamentous fungi in the formation of biofilms, including: Cryptococcus neoformans, Cryptococcus gattii, Rhodotorula species, Aspergillus fumigatus, Malassezia pachydermatis, Histoplasma capsulatum, Paracoccidioides brasiliensis, Pneumocystis species, Coccidioides immitis, Fusarium species, Saccharomyces cerevisiae, Trichosporon asahii, Mucorales and Blastoschizomyces. There is a current interest in describing the particular characteristics of the biofilm formation by of these fungi. A major concern is the control of biofilms, requiring knowledge of the biofilm mechanisms. However, our knowledge of these microbial communities is limited, due to the complexity of these systems and metabolic interactions that remain unknown. This mini-review aims to highlight recently discovered fungal biofilms and to compare them with the current knowledge on biofilms. This manuscript is part of the series of works presented at the "V International Workshop: Molecular genetic approaches to the study of human pathogenic fungi" (Oaxaca, Mexico, 2012). Copyright © 2013 Revista Iberoamericana de Micología. Published by Elsevier Espana. All rights reserved.

  4. Experimental evolution in biofilm populations

    Science.gov (United States)

    Steenackers, Hans P.; Parijs, Ilse; Foster, Kevin R.; Vanderleyden, Jozef

    2016-01-01

    Biofilms are a major form of microbial life in which cells form dense surface associated communities that can persist for many generations. The long-life of biofilm communities means that they can be strongly shaped by evolutionary processes. Here, we review the experimental study of evolution in biofilm communities. We first provide an overview of the different experimental models used to study biofilm evolution and their associated advantages and disadvantages. We then illustrate the vast amount of diversification observed during biofilm evolution, and we discuss (i) potential ecological and evolutionary processes behind the observed diversification, (ii) recent insights into the genetics of adaptive diversification, (iii) the striking degree of parallelism between evolution experiments and real-life biofilms and (iv) potential consequences of diversification. In the second part, we discuss the insights provided by evolution experiments in how biofilm growth and structure can promote cooperative phenotypes. Overall, our analysis points to an important role of biofilm diversification and cooperation in bacterial survival and productivity. Deeper understanding of both processes is of key importance to design improved antimicrobial strategies and diagnostic techniques. PMID:26895713

  5. Bacterial Biofilms in Jones Tubes.

    Science.gov (United States)

    Ahn, Eric S; Hauck, Matthew J; Kirk Harris, Jonathan; Robertson, Charles E; Dailey, Roger A

    To investigate the presence and microbiology of bacterial biofilms on Jones tubes (JTs) by direct visualization with scanning electron microscopy and polymerase chain reaction (PCR) of representative JTs, and to correlate these findings with inflammation and/or infection related to the JT. In this study, prospective case series were performed. JTs were recovered from consecutive patients presenting to clinic for routine cleaning or recurrent irritation/infection. Four tubes were processed for scanning electron microscopy alone to visualize evidence of biofilms. Two tubes underwent PCR alone for bacterial quantification. One tube was divided in half and sent for scanning electron microscopy and PCR. Symptoms related to the JTs were recorded at the time of recovery. Seven tubes were obtained. Five underwent SEM, and 3 out of 5 showed evidence of biofilms (60%). Two of the 3 biofilms demonstrated cocci and the third revealed rods. Three tubes underwent PCR. The predominant bacteria identified were Pseudomonadales (39%), Pseudomonas (16%), and Staphylococcus (14%). Three of the 7 patients (43%) reported irritation and discharge at presentation. Two symptomatic patients, whose tubes were imaged only, revealed biofilms. The third symptomatic patient's tube underwent PCR only, showing predominantly Staphylococcus (56%) and Haemophilus (36%) species. Two of the 4 asymptomatic patients also showed biofilms. All symptomatic patients improved rapidly after tube exchange and steroid antibiotic drops. Bacterial biofilms were variably present on JTs, and did not always correlate with patients' symptoms. Nevertheless, routine JT cleaning is recommended to treat and possibly prevent inflammation caused by biofilms.

  6. Microbial biofilms on facial prostheses

    NARCIS (Netherlands)

    Ariani, Nina; Vissink, Arjan; van Oort, Robert P.; Kusdhany, Lindawati; Djais, Ariadna; Rahardjo, Tri Budi W.; van der Mei, Henny C.; Krom, Bastiaan P.

    2012-01-01

    The composition of microbial biofilms on silicone rubber facial prostheses was investigated and compared with the microbial flora on healthy and prosthesis-covered skin. Scanning electron microscopy showed the presence of mixed bacterial and yeast biofilms on and deterioration of the surface of the

  7. Microalgal biofilms for wastewater treatment

    NARCIS (Netherlands)

    Boelee, N.C.

    2013-01-01

    The objective of this thesis was to explore the possibilities of using microalgal biofilms for the treatment of municipal wastewater, with a focus on the post-treatment of municipal wastewater effluent. The potential of microalgal biofilms for wastewater treatment was first investigated using a

  8. Sustained effects of blue light on Streptococcus mutans in regrown biofilm.

    Science.gov (United States)

    Cohen-Berneron, Julie; Steinberg, Doron; Featherstone, John D B; Feuerstein, Osnat

    2016-04-01

    In prior studies, exposure of Streptococcus mutans in biofilm to blue light using high fluences of up to 680 J/cm(2) did not interfere with bacterial capability to reform an initial biofilm; however, a delayed antibacterial effect was observed. Our aim was to determine the sustained effecttts of blue light-emitting diode (LED) curing light on the pathogenicity of the newly formed biofilm. S. mutans were grown to form biofilm that was exposed to blue light (wavelengths, 460-480 nm) for 1, 3, and 7 min (equivalent to 37, 112, and 262 J/cm(2), respectively). Then, bacteria were suspended and allowed to regrow into new biofilms. The regrown biofilms were assessed for bacterial quantification by optical density (OD) measurement and quantitative polymerase chain reaction (qPCR), bacterial viability and extracellular polysaccharide production by fluorescent staining using confocal scanning laser microscopy, acid production by bacteria (acidogenicity), and bacterial survival at low pH (aciduricity) using qPCR. Bacterial growth in the regrown biofilms was increased when samples were previously exposed to light; however, under the confocal microscopy, a higher proportion of dead bacteria and a reduction in polysaccharide production were observed. The acidogenicity from the regrown biofilm was lowered as fluences of light increased. The aciduricity of the regrown biofilm was decreased, meaning less growth of bacteria into biofilm in low pH with increasing fluences. Blue light has sustained effects on S. mutans bacteria grown into new biofilm. Although bacterial growth in biofilm increased, bacterial viability and virulence characteristics were impaired. The cariogenic potential over time of S. mutans previously exposed to blue light when grown on tooth surfaces is yet to be determined.

  9. [Biofilm formation capacity of Listeria monocytogens strains isolated from soft cheese from Costa Rica].

    Science.gov (United States)

    Carrillo Zeledón, Gabriela; Redondo Solano, Mauricio; Arias Echandi, María Laura

    2010-06-01

    Listeria monocytogenes is a bacteria associated with the production of severe infectious disease in human being, but also with the formation of biofilms in different surfaces related to the food production environment. Biofilm represents a serious problem in food industry, since it is a constant and important contamination source and also, bacteria present in it have an increased resistance towards physical and chemical agents of common use. The capacity of biofilm formation of L. monocytogenes strains previously isolated from soft cheese samples from Costa Rica was studied under different temperature and culture conditions. The microplate technique was performed using different culture media (BHIB, TSB 1:20 and cheese serum) and at different incubation temperatures (refrigeration, environmental and 35 degrees C). Biofilm formation capacity was classified according to the optical density obtained at 620 nm. None of the strains evaluated was classified as strong biofilm former under any of the variables studied, nevertheless, weak and moderate formers were detected. The results obtained show the influence of the nutrient content of the culture media used over biofilm formation; BHIB was the only culture media that allowed the expression of moderate biofilm forms, contrary to cheese serum that did not promote biofilm production. Biofilm formation is a multifactorial process, where adsorption level depends on several variables and its study must be promoted in order to develop methodologies that allow its reduction or elimination, so food industries may offer safe food products to consumers.

  10. Biofilm bacterial communities in urban drinking water distribution systems transporting waters with different purification strategies.

    Science.gov (United States)

    Wu, Huiting; Zhang, Jingxu; Mi, Zilong; Xie, Shuguang; Chen, Chao; Zhang, Xiaojian

    2015-02-01

    Biofilm formation in drinking water distribution systems (DWDS) has many adverse consequences. Knowledge of microbial community structure of DWDS biofilm can aid in the design of an effective control strategy. However, biofilm bacterial community in real DWDS and the impact of drinking water purification strategy remain unclear. The present study investigated the composition and diversity of biofilm bacterial community in real DWDSs transporting waters with different purification strategies (conventional treatment and integrated treatment). High-throughput Illumina MiSeq sequencing analysis illustrated a large shift in the diversity and structure of biofilm bacterial community in real DWDS. Proteobacteria, Firmicutes, Bacteroidetes, Actinobacteria, Nitrospirae, and Cyanobacteria were the major components of biofilm bacterial community. Proteobacteria (mainly Alphaproteobacteria, Betaproteobacteria, and Gammaproteobacteria) predominated in each DWDS biofilm, but the compositions of the dominant proteobacterial classes and genera and their proportions varied among biofilm samples. Drinking water purification strategy could shape DWDS biofilm bacterial community. Moreover, Pearson's correlation analysis indicated that Actinobacteria was positively correlated with the levels of total alkalinity and dissolved organic carbon in tap water, while Firmicutes had a significant positive correlation with nitrite nitrogen.

  11. Influence of glycemic control on the levels of subgingival periodontal pathogens in patients with generalized chronic periodontitis and type 2 diabetes.

    Science.gov (United States)

    Miranda, Tamires Szeremeske; Feres, Magda; Retamal-Valdés, Belén; Perez-Chaparro, Paula Juliana; Maciel, Suellen Silva; Duarte, Poliana Mendes

    2017-01-01

    This study evaluated the influence of glycemic control on the levels and frequency of subgingival periodontal pathogens in patients with type 2 diabetes mellitus (DM) and generalized chronic periodontitis (ChP). Fifty-six patients with generalized ChP and type 2 DM were assigned according to the levels of glycated hemoglobin (HbA1c) into one of the following groups: HbA1ctype 2 DM and ChP.

  12. Presence of Helicobacter pylori in subgingival plaque of periodontitis patients with and without dyspepsia, detected by polymerase chain reaction and culture

    OpenAIRE

    Agarwal, Sangita; Jithendra, K. D.

    2012-01-01

    Background: Helicobacter pylori is an important gastrointestinal pathogen that is strongly associated with gastritis as well as peptic ulcer disease. Antimicrobial therapy frequently fails to cure H. pylori infection, which suggests there may be sanctuary sites where the organism resides. This study was aimed to assess the role of oral cavity as a reservoir of H. pylori by evaluating the occurrence of the organism in subgingival plaque of dyspeptic patients by polymerase chain reaction as wel...

  13. The development of biofilm architecture.

    Science.gov (United States)

    Fowler, A C; Kyrke-Smith, T M; Winstanley, H F

    2016-04-01

    We extend the one-dimensional polymer solution theory of bacterial biofilm growth described by Winstanley et al . (2011 Proc. R. Soc. A 467 , 1449-1467 (doi:10.1098/rspa.2010.0327)) to deal with the problem of the growth of a patch of biofilm in more than one lateral dimension. The extension is non-trivial, as it requires consideration of the rheology of the polymer phase. We use a novel asymptotic technique to reduce the model to a free-boundary problem governed by the equations of Stokes flow with non-standard boundary conditions. We then consider the stability of laterally uniform biofilm growth, and show that the model predicts spatial instability; this is confirmed by a direct numerical solution of the governing equations. The instability results in cusp formation at the biofilm surface and provides an explanation for the common observation of patterned biofilm architectures.

  14. Bacterial interactions in dental biofilm.

    Science.gov (United States)

    Huang, Ruijie; Li, Mingyun; Gregory, Richard L

    2011-01-01

    Biofilms are masses of microorganisms that bind to and multiply on a solid surface, typically with a fluid bathing the microbes. The microorganisms that are not attached but are free floating in an aqueous environment are termed planktonic cells. Traditionally, microbiology research has addressed results from planktonic bacterial cells. However, many recent studies have indicated that biofilms are the preferred form of growth of most microbes and particularly those of a pathogenic nature. Biofilms on animal hosts have significantly increased resistance to various antimicrobials compared to planktonic cells. These microbial communities form microcolonies that interact with each other using very sophisticated communication methods (i.e., quorum-sensing). The development of unique microbiological tools to detect and assess the various biofilms around us is a tremendously important focus of research in many laboratories. In the present review, we discuss the major biofilm mechanisms and the interactions among oral bacteria.

  15. Antibiotic tolerance and microbial biofilms

    DEFF Research Database (Denmark)

    Folkesson, Anders

    Increased tolerance to antimicrobial agents is thought to be an important feature of microbes growing in biofilms. We study the dynamics of antibiotic action within hydrodynamic flow chamber biofilms of Escherichia coli and Pseudomonas aeruginosa using isogenic mutants and fluorescent gene...... expression reporters and we address the question of how biofilm organization affects antibiotic susceptibility. The dynamics of microbial killing is monitored by viable count determination, and confocal laser microscopy. Our work shows that the apparent increased antibiotic tolerance is due to the formation...... of antibiotic tolerant subpopulations within the biofilm. The formation of these subpopulations is highly variable and dependent on the antibiotic used, the biofilm structural organization and the induction of specific tolerance mechanisms....

  16. Antimicrobial resistance and in vitro biofilm-forming ability of Enterococci spp. isolated from urinary tract infection in a tertiary care hospital in Dhaka.

    Science.gov (United States)

    Akhter, J; Ahmed, S; Saleh, A A; Anwar, S

    2014-04-01

    The biofilm mode of life conveys a survival advantage to the microorganism associated with it. Biofilm on an indwelling urinary catheter consists of adherent microorganisms, their extra cellular products, and host components deposited on the catheter and thus biofilm on urinary catheters results in persistent infections that are resistant to antimicrobial therapy. This study was done during the period of January 2010 to December 2010. Fifty nine enterococci isolated from 1203 urine samples were speciated by conventional microbiological methods and examined for their ability to form biofilm by microtitre plate assay and antimicrobial susceptibility testing by disc diffusion method for 10 clinically relevant antibiotics respectively. Biofilm producing Enterococci were more frequently found in catheterized than in non catheterized patient (p biofilm production with antibiotic resistance to amoxicillin, co-trimoxazole, ciprofloxacin, gentamycin, cefotaxime, and cefuroxime. This study demonstrated a high propensity among the isolates of Enterococci to form biofilm and a significant association of biofilms with multiple drug resistance.

  17. Oral biofilm models for mechanical plaque removal

    NARCIS (Netherlands)

    Verkaik, Martinus J.; Busscher, Henk J.; Rustema-Abbing, Minie; Slomp, Anje M.; Abbas, Frank; van der Mei, Henny C.

    In vitro plaque removal studies require biofilm models that resemble in vivo dental plaque. Here, we compare contact and non-contact removal of single and dual-species biofilms as well as of biofilms grown from human whole saliva in vitro using different biofilm models. Bacteria were adhered to a

  18. Oral Biofilm Architecture on Natural Teeth

    NARCIS (Netherlands)

    Zijnge, Vincent; van Leeuwen, M. Barbara M.; Degener, John E.; Abbas, Frank; Thurnheer, Thomas; Gmuer, Rudolf; Harmsen, Hermie J. M.

    2010-01-01

    Periodontitis and caries are infectious diseases of the oral cavity in which oral biofilms play a causative role. Moreover, oral biofilms are widely studied as model systems for bacterial adhesion, biofilm development, and biofilm resistance to antibiotics, due to their widespread presence and

  19. Growing and analyzing biofilms in flow chambers

    DEFF Research Database (Denmark)

    Tolker-Nielsen, Tim; Sternberg, Claus

    2011-01-01

    This unit describes the setup of flow chamber systems for the study of microbial biofilms, and methods for the analysis of structural biofilm formation. Use of flow chambers allows direct microscopic investigation of biofilm formation. The biofilms in flow chambers develop under hydrodynamic cond...

  20. Impact of Hydrodynamics on Oral Biofilm Strength

    NARCIS (Netherlands)

    Paramonova, E.; Kalmykowa, O. J.; van der Mei, H. C.; Busscher, H. J.; Sharma, P. K.

    2009-01-01

    Mechanical removal of oral biofilms is ubiquitously accepted as the best way to prevent caries and periodontal diseases. Removal effectiveness strongly depends on biofilm strength. To investigate the influence of hydrodynamics on oral biofilm strength, we grew single- and multi-species biofilms of

  1. Bacterial biofilms: prokaryotic adventures in multicellularity

    DEFF Research Database (Denmark)

    Webb, J.S.; Givskov, Michael Christian; Kjelleberg, S.

    2003-01-01

    The development of bacterial biofilms includes both the initial social behavior of undifferentiated cells, as well as cell death and differentiation in the mature biofilm, and displays several striking similarities with higher organisms. Recent advances in the field provide new insight...... into differentiation and cell death events in bacterial biofilm development and propose that biofilms have an unexpected level of multicellularity....

  2. Biofilms and host response - helpful or harmful

    DEFF Research Database (Denmark)

    Moser, Claus; Pedersen, Hannah Trøstrup; Lerche, Christian Johann

    2017-01-01

    Biofilm infections are one of the modern medical world's greatest challenges. Probably, all non-obligate intracellular bacteria and fungi can establish biofilms. In addition, there are numerous biofilm-related infections, both foreign body-related and non-foreign body-related. Although biofilm in...

  3. A short history of microbial biofilms and biofilm infections.

    Science.gov (United States)

    Høiby, Niels

    2017-04-01

    The observation of aggregated microbes surrounded by a self-produced matrix adhering to surfaces or located in tissues or secretions is old since both Leeuwenhoek and Pasteur have described the phenomenon. In environmental and technical microbiology, biofilms, 80-90 years ago, were already shown to be important for biofouling on submerged surfaces, for example, ships. The concept of biofilm infections and their importance in medicine was, however, initiated in the early 1970s by the observation of heaps of Pseudomonas aeruginosa cells in sputum and lung tissue from chronically infected cystic fibrosis patients. The term biofilm was introduced into medicine in 1985 by J. W. Costerton. During the following decades, the number of published biofilm articles and methods for studying biofilms increased rapidly and it was shown that adhering and nonadhering biofilm infections are widespread in medicine. The medical importance of biofilm infections is now generally accepted and guidelines for prophylaxis, diagnosis, and treatment have been published. © 2017 APMIS. Published by John Wiley & Sons Ltd.

  4. The Role of Bacterial Biofilm in Adverse Soft-Tissue Filler Reactions: A Combined Laboratory and Clinical Study.

    Science.gov (United States)

    Saththianathan, Mayuran; Johani, Khalid; Taylor, Alaina; Hu, Hongua; Vickery, Karen; Callan, Peter; Deva, Anand K

    2017-03-01

    The development of chronic nodules and granulomatous inflammation after filler injections has been attributed to bacterial biofilm infection. The authors aimed to investigate the relationship between filler and bacterial biofilm using a combined in vitro and in vivo study. In vitro assays to investigate the ability of filler materials to support the growth of Staphylococcus epidermidis biofilm and the effect of multiple needle passes through a biofilm-contaminated surface were designed. Analysis of clinical biopsy specimens from patients presenting with chronic granulomas following filler administration using a number of laboratory tests for biofilm was performed. All fillers (i.e., hyaluronic acid, polyacrylamide gel, and poly-L-lactic acid) supported the growth of S. epidermidis biofilm in vitro. Multiple needle passes through a biofilm-contaminated surface resulted in significantly increased contamination of filler material by a factor of 10,000 (p bacterial biofilm. The mean number of bacteria was found to be 2.2 × 10 bacteria/mg tissue (range, 5.6 × 10 to 3.7 × 10 bacteria/mg tissue). Microbiome analysis detected a predominance of Pseudomonas, Staphylococcus, and Propionibacterium as present in these samples. Filler material can support the growth of bacterial biofilm in vitro. Multiple needle passes can significantly increase the risk of filler contamination. Biofilm appears to be associated with high numbers in clinical samples of patients presenting with chronic granulomatous inflammation. Strategies to reduce the risk of bacterial contamination need to be further studied and translated into clinical practice. Therapeutic, V.

  5. Dose requirements for UVC disinfection of catheter biofilms

    DEFF Research Database (Denmark)

    Bak, Jimmy; Ladefoged, Søren D.; Tvede, Michael

    2009-01-01

    doses to kill catheter biofilm. Given these doses and the power of available UVC light sources, calculation of the necessary treatment times is then possible. To determine the required doses, contaminated urinary catheters were used as test samples and UVC treated in vitro. Patient catheters (n = 67......Bacterial biofilms on permanent catheters are the major sources of infection. Exposure to ultraviolet-C (UVC) light has been proposed as a method for disinfecting the inner surface of catheters. Specification of a UVC-based device for in vivo disinfection is based on the knowledge of the required......) were collected and cut into segments of equal size and treated with various UVC doses. After treatment, the biofilm was removed by scraping and quantified by counting colony forming units. Percentage killing rates were determined by calculating ratios between UVC-treated samples and controls (no UVC...

  6. Bacterial biofilm in chronic lesions of Hidradenitis Suppurativa

    DEFF Research Database (Denmark)

    Ring, H C; Bay, L; Nilsson, M

    2017-01-01

    BACKGROUND: Chronic non-healing or recurrent inflammatory lesions, reminiscent of infection but recalcitrant to antibiotic therapy generally characterize biofilm driven-diseases. Chronic lesions of Hidradenitis Suppurativa (HS) exhibit several aspects, which are compatible with well-known biofilm...... infections. OBJECTIVE: To determine and quantify the potential presence of bacterial aggregates in chronic HS lesions. METHODS: In 42 consecutive HS patients suffering from chronic lesions, biopsies were obtained from lesional as well as from perilesional skin. Samples were investigated using Peptide Nucleic...... (aggregates > 50 μm in diameter) were situated in sinus tracts (63%) or in the infundibulum (37%). The majority of the sinus tract samples (73%) contained active bacterial cells, which were associated with inflammation. CONCLUSION: This study suggests that biofilm is associated with inflammation of chronic HS...

  7. Pseudomonas aeruginosa Biofilms

    DEFF Research Database (Denmark)

    Alhede, Maria; Bjarnsholt, Thomas; Givskov, Michael

    2014-01-01

    The opportunistic gram-negative bacterium Pseudomonas aeruginosa is implicated in many chronic infections and is readily isolated from chronic wounds, medical devices, and the lungs of cystic fibrosis patients. P. aeruginosa is believed to persist in the host organism due to its capacity to form...... biofilms, which protect the aggregated, biopolymer-embedded bacteria from the detrimental actions of antibiotic treatments and host immunity. A key component in the protection against innate immunity is rhamnolipid, which is a quorum sensing (QS)-regulated virulence factor. QS is a cell-to-cell signaling...

  8. Nanoparticle silver ion coatings inhibit biofilm formation on titanium implants.

    Science.gov (United States)

    Secinti, Kutsal Devrim; Özalp, Hakan; Attar, Ayhan; Sargon, Mustafa F

    2011-03-01

    The formation of bacterial biofilm on the surface of implanted metal objects is a major clinical problem. The antibacterial and antifungal effect of silver ions has been long known, and seems to give silver the capability to inhibit biofilm formation. To test the effect of silver ions, 20 New Zealand rabbits had bacteria applied to a screw insertion site at the iliac crest, and were then randomly divided into two groups: Group I, which had silver-coated screws applied, and Group II, which had uncoated titanium screws. After the rabbits were sacrificed on day 28, we examined the screws, the bone adjacent to the screws, and the liver, kidneys, brain and corneas of both groups under transmission (TEM) and scanning electron microscopy (SEM). We also analysed microbiological samples from the screw holes. All silver-coated screws, but only 10% of uncoated titanium screws, were sterile. All tissue samples appeared ultrastructurally normal in both groups. Biofilm formation was inhibited on all silver-coated screws, but all uncoated screws developed a biofilm on their surfaces. Our findings suggest that nanoparticle silver ion-coated implants are as safe as uncoated titanium screws and that they can help prevent both biofilm formation and infection. Copyright © 2010 Elsevier Ltd. All rights reserved.

  9. Metabolic activity, urease production, antibiotic resistance and virulence in dual species biofilms of Staphylococcus epidermidis and Staphylococcus aureus.

    Science.gov (United States)

    Vandecandelaere, Ilse; Van Nieuwerburgh, Filip; Deforce, Dieter; Coenye, Tom

    2017-01-01

    In this paper, the metabolic activity in single and dual species biofilms of Staphylococcus epidermidis and Staphylococcus aureus isolates was investigated. Our results demonstrated that there was less metabolic activity in dual species biofilms compared to S. aureus biofilms. However, this was not observed if S. aureus and S. epidermidis were obtained from the same sample. The largest effect on metabolic activity was observed in biofilms of S. aureus Mu50 and S. epidermidis ET-024. A transcriptomic analysis of these dual species biofilms showed that urease genes and genes encoding proteins involved in metabolism were downregulated in comparison to monospecies biofilms. These results were subsequently confirmed by phenotypic assays. As metabolic activity is related to acid production, the pH in dual species biofilms was slightly higher compared to S. aureus Mu50 biofilms. Our results showed that S. epidermidis ET-024 in dual species biofilms inhibits metabolic activity of S. aureus Mu50, leading to less acid production. As a consequence, less urease activity is required to compensate for low pH. Importantly, this effect was biofilm-specific. Also S. aureus Mu50 genes encoding virulence-associated proteins (Spa, SplF and Dps) were upregulated in dual species biofilms compared to monospecies biofilms and using Caenorhabditis elegans infection assays, we demonstrated that more nematodes survived when co-infected with S. epidermidis ET-024 and S. aureus mutants lacking functional spa, splF or dps genes, compared to nematodes infected with S. epidermidis ET-024 and wild- type S. aureus. Finally, S. epidermidis ET-024 genes encoding resistance to oxacillin, erythromycin and tobramycin were upregulated in dual species biofilms and increased resistance was subsequently confirmed. Our data indicate that both species in dual species biofilms of S. epidermidis and S. aureus influence each other's behavior, but additional studies are required necessary to elucidate the exact

  10. Strategies for combating bacterial biofilm infections

    OpenAIRE

    Wu, Hong; Moser, Claus; Wang, Heng-Zhuang; H?iby, Niels; Song, Zhi-Jun

    2014-01-01

    Formation of biofilm is a survival strategy for bacteria and fungi to adapt to their living environment, especially in the hostile environment. Under the protection of biofilm, microbial cells in biofilm become tolerant and resistant to antibiotics and the immune responses, which increases the difficulties for the clinical treatment of biofilm infections. Clinical and laboratory investigations demonstrated a perspicuous correlation between biofilm infection and medical foreign bodies or indwe...

  11. Draft Genome Sequences of Biofilm-Forming and Non-Biofilm-Forming Nontyphoidal Salmonella enterica Serovars

    OpenAIRE

    Shetty, Deeksha; Grigoryan, Alexander A.; Alshalchi, Sahar; Withana Gamage, Niradha; Roy, Julie; Lawrence, John R.; Vidovic, Sinisa; Korber, Darren R.

    2017-01-01

    ABSTRACT The genetic basis for biofilm formation among nontyphoidal salmonellae (NTS) remains poorly understood. This draft genome submission provides initial insights on the genetic differences between biofilm-forming and non-biofilm-forming clinical and environmental NTS serovars.

  12. Multi drug resistance in strong biofilm forming clinical isolates of Staphylococcus epidermidis.

    Science.gov (United States)

    Sahal, Gulcan; Bilkay, Isil Seyis

    2014-01-01

    Staphylococcus epidermidis which exists in healthy human skin as a commensal inhabitant is also an important pathogen forming biofilms on many surfaces and recently, increased resistance traits were suggested to be acquired in biofilm environments. In this study; clinical Prevalences, antibiotic resistances and biofilm formations of S. epidermidis strains were determined and comparison of all these findings with each other was carried out in order to take precautions against them and figure out if high biofilm forming S. epidermidis strains display multi drug resistance. According to our results; samples of wound and blood were the most S. epidermidis isolated clinical materials (40%; 35%) and cardiothoracic surgery was the most S. epidermidis observed service unit. All of these strains were sensitive to vancomycin, however 65% of them showed resistance to all β-lactam antibiotics (Penicillin, Oxacillin, Amoxicilin/Clavulonic acid), used in this study and 60% of all S. epidermidis strains were found as multi drug resistant. When the results of strong biofilm forming S. epidermidis strains are examined; they were isolated from sample of blood and service unit of cardiovascular surgery in highest frequency and 80% of them were β-lactam resistant whereas 100% of them were multi drug resistant. One of these multi drug resistant strains which was resistant to maximum amount of different antimicrobial classes, was also observed as maximum biofilm forming strain among all the other S. epidermidis isolates. Multi drug resistance in strong biofilm forming strains shows that; biofilms play a role in antimicrobial resistance traits of S. epidermidis.

  13. Clinical implications of microbial biofilms in chronic rhinosinusitis and orbital cellulitis.

    Science.gov (United States)

    Nayak, Niranjan; Satpathy, Gita; Prasad, Sujata; Thakar, Alok; Chandra, Mahesh; Nag, T C

    2016-09-21

    Discovery of sessile mode of microbial existence (Biofilm state) focussed much interest, during the recent years, on the study of biofilms in many recurring and chronic infections. However, the exact role of microbial biofilms in chronic rhinosinusitis and orbital cellulitis were not elucidated earlier. The purpose of the present study was to look for the adherent property and biofilm producing ability of the clinical isolates in chronic rhinosinusitis and orbital cellulitis, and to look for the effects of antimicrobial agents on these biofilms by colorimetric assay and ultrastructural analysis. Organisms were isolated and identified from various clinical samples in patients with chronic sinusitis and orbital cellulitis. Antimicrobial sensitivity testing was carried out by the standard protocol. Biofilms were developed; quantified and antimicrobial drug perfusion through the biofilm model was evaluated by the earlier devised procedure. Electronmicroscopic study of the biofilm was performed by the recommended technique. Of the total of 70 clinical samples processed, 48 i.e. 68.5 % grew bacteria and 13 i.e.(18.6 %) fungi. Staphylococcus aureus (20), S epidermidis (16) and Pseudomonas aeruginosa (6) accounted for the majority of the bacterial isolates. Aspergillus flavus (8), however was the commonest amongst the fungi. A total of 40 bacteria and 8 fungi could be tested for biofilm production. Eighteen (45 %) of the 40 bacterial isolates and 4(50 %) out of the 8 A flavus isolates were found to be biofilm producers. In vitro adherence testing revealed that majority i.e. 16 (88.8 %) of the 18 biofilm positive bacteria were adherent to artificial surfaces. Antimicrobial drug perfusion through the biofilm model was poor. Antimicrobial treatment was totally ineffective against strong biofilm producers, whose electron microscopic picture was quite similar to that observed for biofilm producers without any antimicrobial pre-treatment. Filamentous fungi, like bacteria

  14. Fungal Biofilms and Polymicrobial Diseases.

    Science.gov (United States)

    Costa-Orlandi, Caroline B; Sardi, Janaina C O; Pitangui, Nayla S; de Oliveira, Haroldo C; Scorzoni, Liliana; Galeane, Mariana C; Medina-Alarcón, Kaila P; Melo, Wanessa C M A; Marcelino, Mônica Y; Braz, Jaqueline D; Fusco-Almeida, Ana Marisa; Mendes-Giannini, Maria José S

    2017-05-10

    Biofilm formation is an important virulence factor for pathogenic fungi. Both yeasts and filamentous fungi can adhere to biotic and abiotic surfaces, developing into highly organized communities that are resistant to antimicrobials and environmental conditions. In recent years, new genera of fungi have been correlated with biofilm formation. However, Candida biofilms remain the most widely studied from the morphological and molecular perspectives. Biofilms formed by yeast and filamentous fungi present differences, and studies of polymicrobial communities have become increasingly important. A key feature of resistance is the extracellular matrix, which covers and protects biofilm cells from the surrounding environment. Furthermore, to achieve cell-cell communication, microorganisms secrete quorum-sensing molecules that control their biological activities and behaviors and play a role in fungal resistance and pathogenicity. Several in vitro techniques have been developed to study fungal biofilms, from colorimetric methods to omics approaches that aim to identify new therapeutic strategies by developing new compounds to combat these microbial communities as well as new diagnostic tools to identify these complex formations in vivo. In this review, recent advances related to pathogenic fungal biofilms are addressed.

  15. Fungal Biofilms and Polymicrobial Diseases

    Science.gov (United States)

    Costa-Orlandi, Caroline B.; Sardi, Janaina C. O.; Pitangui, Nayla S.; de Oliveira, Haroldo C.; Scorzoni, Liliana; Galeane, Mariana C.; Medina-Alarcón, Kaila P.; Melo, Wanessa C. M. A.; Marcelino, Mônica Y.; Braz, Jaqueline D.; Fusco-Almeida, Ana Marisa; Mendes-Giannini, Maria José S.

    2017-01-01

    Biofilm formation is an important virulence factor for pathogenic fungi. Both yeasts and filamentous fungi can adhere to biotic and abiotic surfaces, developing into highly organized communities that are resistant to antimicrobials and environmental conditions. In recent years, new genera of fungi have been correlated with biofilm formation. However, Candida biofilms remain the most widely studied from the morphological and molecular perspectives. Biofilms formed by yeast and filamentous fungi present differences, and studies of polymicrobial communities have become increasingly important. A key feature of resistance is the extracellular matrix, which covers and protects biofilm cells from the surrounding environment. Furthermore, to achieve cell–cell communication, microorganisms secrete quorum-sensing molecules that control their biological activities and behaviors and play a role in fungal resistance and pathogenicity. Several in vitro techniques have been developed to study fungal biofilms, from colorimetric methods to omics approaches that aim to identify new therapeutic strategies by developing new compounds to combat these microbial communities as well as new diagnostic tools to identify these complex formations in vivo. In this review, recent advances related to pathogenic fungal biofilms are addressed. PMID:29371540

  16. EFEKTIFITAS SKELING-PENGHALUSAN AKAR DENGAN DAN TANPA APLIKASI SUBGINGIVAL POVIDON-IODIN 10% PADA POKET 5-7mm

    Directory of Open Access Journals (Sweden)

    Irma Ervina

    2015-08-01

    Full Text Available In deep periodontal lesions, scaling and root planning (SRP failed to complete elimination of periodontal bacteria, so chemical antimicrobial agents are used topically to destroy microorganism. Povidon-iodin 10% is one of antimicrobial agents that can be applied topically and directly in the pocket. The aim of the research were evaluated the efficacy of povidon-iodin 10% as chemical antimicrobial agents locally applied into periodontal pocket. The data are obtained from patients with chronic adult periodontitis, baseline periodontal pocket depth (PPD are 5-7 mm. The teeth are scaled and root planed after clinical examinations (plaque index, papilla bleeding index and periodontal pocket depth and test sites or control sites are assigned randomly. Topically application of povidon-iodin 10% at test sites and aquabides at control sites is applied at day 1st and day 7th. The clinical parameters are assessed at day 14th. The results of the research showed that application of povidon-iodin 10% after SRP provide statistically significant more favorable papilla bleeding index reduction than SRP + aquabides after 14 day. The pocket depth reduction at test sites are greater than control cites (baseline PPD=6 and 7 mm. The conclusions of the research showed that application subgingival povidon-iodin 10% as adjuctive to SRP significantly reduce PBI and PPD (6 & 7 mm than without application povidon-iodin 10%.

  17. Effect of repeated adjunctive antimicrobial photodynamic therapy on subgingival periodontal pathogens in the treatment of chronic periodontitis.

    Science.gov (United States)

    Petelin, Milan; Perkič, Katja; Seme, Katja; Gašpirc, Boris

    2015-08-01

    The aim of this study was to compare the effect of subgingival ultrasonic scaling followed by repeated (three times) antimicrobial photodynamic therapy (PDT), ultrasonic scaling alone (US), and scaling and root planing with hand instruments (SRP) for initial periodontal treatment. Twenty-seven non-smoking systemically healthy chronic periodontitis patients were included. Residual pockets ≥4 mm deep and bleeding on probing were debrided either with SRP, US alone, or US followed by a single episode of PDT during supportive periodontal treatment. Probing pocket depth (PPD), bleeding on probing (BOP), and clinical attachment level (CAL) were monitored over 12 months. The presence of five periodontal pathogens in the pockets was determined by a commercially available micro-IDent test. Intergroup and intragroup statistical analysis was performed. All three treatments resulted in a significant clinical improvement. Additional application of PDT to US failed to result in further improvement in terms of PPD reduction and CAL gain. However, it resulted in a higher reduction of BOP at 3 and 12 months comparing to US alone or SRP (PDT from 25 to 13 and to 9%, US from 23 to 16 and to 12%, and SRP from 17 to 10 and to 9%, respectively). PDT reduced the proportion of positive sites after 6 months for Treponema denticola (TD) significantly more effectively than US or SRP (p 6 mm) compared to mechanical debridement alone (p < 0.05).

  18. Temporal variations in the abundance and composition of biofilm communities colonizing drinking water distribution pipes.

    Directory of Open Access Journals (Sweden)

    John J Kelly

    Full Text Available Pipes that transport drinking water through municipal drinking water distribution systems (DWDS are challenging habitats for microorganisms. Distribution networks are dark, oligotrophic and contain disinfectants; yet microbes frequently form biofilms attached to interior surfaces of DWDS pipes. Relatively little is known about the species composition and ecology of these biofilms due to challenges associated with sample acquisition from actual DWDS. We report the analysis of biofilms from five pipe samples collected from the same region of a DWDS in Florida, USA, over an 18 month period between February 2011 and August 2012. The bacterial abundance and composition of biofilm communities within the pipes were analyzed by heterotrophic plate counts and tag pyrosequencing of 16S rRNA genes, respectively. Bacterial numbers varied significantly based on sampling date and were positively correlated with water temperature and the concentration of nitrate. However, there was no significant relationship between the concentration of disinfectant in the drinking water (monochloramine and the abundance of bacteria within the biofilms. Pyrosequencing analysis identified a total of 677 operational taxonomic units (OTUs (3% distance within the biofilms but indicated that community diversity was low and varied between sampling dates. Biofilms were dominated by a few taxa, specifically Methylomonas, Acinetobacter, Mycobacterium, and Xanthomonadaceae, and the dominant taxa within the biofilms varied dramatically between sampling times. The drinking water characteristics most strongly correlated with bacterial community composition were concentrations of nitrate, ammonium, total chlorine and monochloramine, as well as alkalinity and hardness. Biofilms from the sampling date with the highest nitrate concentration were the most abundant and diverse and were dominated by Acinetobacter.

  19. Temporal variations in the abundance and composition of biofilm communities colonizing drinking water distribution pipes.

    Science.gov (United States)

    Kelly, John J; Minalt, Nicole; Culotti, Alessandro; Pryor, Marsha; Packman, Aaron

    2014-01-01

    Pipes that transport drinking water through municipal drinking water distribution systems (DWDS) are challenging habitats for microorganisms. Distribution networks are dark, oligotrophic and contain disinfectants; yet microbes frequently form biofilms attached to interior surfaces of DWDS pipes. Relatively little is known about the species composition and ecology of these biofilms due to challenges associated with sample acquisition from actual DWDS. We report the analysis of biofilms from five pipe samples collected from the same region of a DWDS in Florida, USA, over an 18 month period between February 2011 and August 2012. The bacterial abundance and composition of biofilm communities within the pipes were analyzed by heterotrophic plate counts and tag pyrosequencing of 16S rRNA genes, respectively. Bacterial numbers varied significantly based on sampling date and were positively correlated with water temperature and the concentration of nitrate. However, there was no significant relationship between the concentration of disinfectant in the drinking water (monochloramine) and the abundance of bacteria within the biofilms. Pyrosequencing analysis identified a total of 677 operational taxonomic units (OTUs) (3% distance) within the biofilms but indicated that community diversity was low and varied between sampling dates. Biofilms were dominated by a few taxa, specifically Methylomonas, Acinetobacter, Mycobacterium, and Xanthomonadaceae, and the dominant taxa within the biofilms varied dramatically between sampling times. The drinking water characteristics most strongly correlated with bacterial community composition were concentrations of nitrate, ammonium, total chlorine and monochloramine, as well as alkalinity and hardness. Biofilms from the sampling date with the highest nitrate concentration were the most abundant and diverse and were dominated by Acinetobacter.

  20. Experimental study of cadmium interaction with periphytic biofilms

    Energy Technology Data Exchange (ETDEWEB)

    Pokrovsky, O.S., E-mail: oleg@lmtg.obs-mip.fr [Geochimie et Biogeochimie Experimentale, UMR 5563, CNRS-OMP-Universite Toulouse, 14 Avenue Edouard Belin, 31400 Toulouse (France); Feurtet-Mazel, A. [Universite de Bordeaux 1, CNRS, UMR 5805 EPOC, Place du Dr Peyneau, 33120 Arcachon (France); Martinez, R.E. [Center for Applied Geosciences, Universitat Tuebingen, Sigwartstrasse 10, Tuebingen 72076 (Germany); Morin, S. [Unite de Recherche Reseaux, Epuration et Qualite des Eaux REQE, Cemagref, 50 Avenue de Verdun, F-33612 Cestas Cedex (France); Baudrimont, M. [Universite de Bordeaux 1, CNRS, UMR 5805 EPOC, Place du Dr Peyneau, 33120 Arcachon (France); Duong, T. [Universite de Bordeaux 1, CNRS, UMR 5805 EPOC, Place du Dr Peyneau, 33120 Arcachon (France)] [Institute of Environmental Technology, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet Road, Cau Giay, Hanoi (Viet Nam); Coste, M. [Unite de Recherche Reseaux, Epuration et Qualite des Eaux REQE, Cemagref, 50 Avenue de Verdun, F-33612 Cestas Cedex (France)

    2010-03-15

    This study addresses the interaction of Cd with natural biofilms of periphytic diatoms grown during different seasons in metal-contaminated and metal-non-contaminated streams, along a tributary of the Lot River, France. Specifically, it aims to test whether the biofilms from contaminated sites have developed a protective mechanism due to high Cd exposure. Towards this goal, reversible adsorption experiments on untreated biofilms were performed in 0.01 M NaNO{sub 3} with a pH ranging from 2 to 8, Cd concentration from 0.5 to 10,000 {mu}g/L and exposure time from 1 to 24 h. Two types of experiments, pH-dependent adsorption edge and constant-pH 'Langmuirian'-type isotherms were conducted. Results were adequately modeled using a Linear Programming Model. It was found that the adsorption capacities of natural biofilm consortia with respect to Cd do not depend on season and are not directly linked to the growth environment. The biofilms grown in non-contaminated (4.6 ppb Cd in solid) and contaminated (570 ppb Cd in solid) settings exhibit similar adsorption capacities in the Cd concentration range in solution of 100-10,000 {mu}g/L but quite different capacities at low Cd concentration (0.5-100 {mu}g/L); unexpectedly, the non-contaminated biofilm adsorbs approximately 10 times more Cd than the contaminated one. It is therefore possible that the strong low-abundant ligands (for example, phosphoryl or sulfhydryls) are already metal-saturated on surfaces of biofilm grown in the contaminated site whereas these sites are still available for metal adsorption in samples grown in non-contaminated sites.

  1. Biofilm models for the practitioner

    DEFF Research Database (Denmark)

    Morgenroth, Eberhard Friedrich; van Loosdrecht, M. C. M.; Wanner, O.

    2000-01-01

    Even though mathematical biofilm models are extensively used in biofilm research, there has been very little application of these models in the engineering practice so far. However, practitioners would be interested in models that can be used as tools to control plant operation under dynamic...... conditions or to help them handle complex interactions between particle removal, carbon oxidation, nitrification, denitrification and biological phosphorus removal. But even though there is a whole range of biofilm models available, it is difficult for the practitioner to select the appropriate modeling...

  2. Inhibitory effect of zinc oxide nanoparticles on pseudomonas aeruginosa biofilm formation

    Directory of Open Access Journals (Sweden)

    Mohammad Hassani Sangani

    2015-04-01

    Full Text Available Objective(s: Bacterial biofilm formation causes many persistent and chronic infections. The matrix protects biofilm bacteria from exposure to innate immune defenses and antibiotic treatments. The purpose of this study was to evaluate the biofilm formation of clinical isolates of Pseudomonas aeruginosa and the activity of zinc oxide nanoparticles (ZnO NPs on biofilm. Materials and Methods: After collecting bacteria from clinical samples of hospitalized patients, the ability of organisms were evaluated to create biofilm by tissue culture plate (TCP assay. ZnO NPs were synthesized by sol gel method and the efficacy of different concentrations (50- 350 µg/ml of ZnO NPs was assessed on biofilm formation and also elimination of pre-formed biofilm by using TCP method. Results:The average diameter of synthesized ZnO NPs was 20 nm. The minimum inhibitory concentration of nanoparticles was 150- 158 μg/ml and the minimum bactericidal concentration was higher (325 µg/ml. All 15 clinical isolates of P. aeruginosa were able to produce biofilm. Treating the organisms with nanoparticles at concentrations of 350 μg/ml resulted in more than 94% inhibition in OD reduction%. Molecular analysis showed that the presence of mRNA of pslA gene after treating bacteria with ZnO NPs for 30 minutes. Conclusion: The results showed that ZnO NPs can inhibit the establishment of P. aeruginosa biofilms and have less effective in removing pre-formed biofilm. However the tested nanoparticles exhibited anti-biofilm effect, but mRNA of pslA gene could be still detected in the medium by RT-PCR technique after 30 minutes treatment with ZnO.

  3. Time dependent enhanced resistance against antibiotics & metal salts by planktonic & biofilm form of Acinetobacter haemolyticus MMC 8 clinical isolate.

    Science.gov (United States)

    Gaidhani, Sharvari Vijaykumar; Raskar, Aartee Vishnu; Poddar, Sharmishtha; Gosavi, Shriya; Sahu, Praveen Kishore; Pardesi, Karishma Rajendra; Bhide, Shobhana V; Chopade, Balu Ananada

    2014-11-01

    Available literature shows paucity of reports describing antibiotic and metal resistance profile of biofilm forming clinical isolates of Acinetobacter haemolyticus. The present study was undertaken to evaluate the antibiotic and metal resistance profile of Indian clinical isolate of A. haemolyticus MMC 8 isolated from human pus sample in planktonic and biofilm form. Antibiotic susceptibility and minimum inhibitory concentration were determined employing broth and agar dilution techniques. Biofilm formation was evaluated quantitatively by microtiter plate method and variation in complex architecture was determined by scanning electron microscopy. Minimum biofilm inhibiting concentration was checked by Calgary biofilm device. Planktonic A. haemolyticus MMC 8 was sensitive to 14 antibiotics, AgNO 3 and HgC1 2 resistant to streptomycin and intermediately resistant to netilmycin and kanamycin. MMC 8 exhibited temporal variation in amount and structure of biofilm. There was 32-4000 and 4-256 fold increase in antibiotic and metal salt concentration, respectively to inhibit biofilm over a period of 72 h as against susceptible planktonic counterparts. Total viable count in the range of 10(5)-10(6) cfu / ml was observed on plating minimum biofilm inhibiting concentration on Muller-Hinton Agar plate without antimicrobial agents. Biofilm forming cells were several folds more resistant to antibiotics and metal salts in comparison to planktonic cells. Presence of unaffected residual cell population indicated presence of persister cells. The results indicate that biofilm formation causes enhanced resistance against antibiotics and metal salts in otherwise susceptible planktonic A. haemolyticus MMC 8.

  4. Potential of Ocimum basilicum L. and Salvia officinalis L. essential oils against biofilms of P. aeruginosa clinical isolates.

    Science.gov (United States)

    Stojanović-Radić, Z; Pejcić, M; Stojanović, N; Sharifi-Rad, J; Stanković, N

    2016-08-29

    Biofilms are complex communities of microorganisms, responsible for more than 60% of the chronic human infections and they represent one of the leading concerns in medicine. Pseudomonas aeruginosa is human pathogenic bacteria which causes numerous diseases and is known for its ability to produce biofilm. Ocimum basilicum L. (basil) and Salvia officinalis L. (sage) are widely used plants in traditional medicine for the treatment of different conditions. Therefore, the aim of this study was to investigate the potential of basil and sage essential oils against P. aeruginosa biofilm producing strains. The efficacy of two essential oils on P. aeruginosa biofilm forming ability was determined using crystal violet method. Out of 15 strains isolated from different clinical biological samples, two were strong, 11 moderate and one weak biofilm producer. Good efficacy of sage essential oil towards strong and weak biofilm producers, but not of basil essential oil, was observed. In the case of moderate biofilm producers, 81.8% showed lower biofilm production after incubation with the sage oil, while 63.6% showed the reduction of biofilm production after basil essential oil treatment. The obtained results showed high potential of both oils for the treatment of persistent infections caused by Pseudomonas aeruginosa biofilms.

  5. Determining productivity of transferred benthic biofilms within wetlands differing in anthropogenic stressors

    Energy Technology Data Exchange (ETDEWEB)

    Frederick, K.; Foote, L. [Alberta Univ., Edmonton, AB (Canada); Ciborowski, J. [Windsor Univ., ON (Canada)

    2010-07-01

    Algal biofilms are a fundamental contributor to wetland productivity. The films maintain high turnover rates, nutrient uptake and storage capacities are prevalent in shallow water as well as over large littoral zones. This study investigated biofilm transfer techniques as a means of accelerating carbon capture, plant production, and colonization in reclaimed oil sand wetlands affected by process water. The study examined the productivity of transferred biofilms and their ability to accelerate succession; methods of transferring biofilms; and the community composition of algae in relation to other substrates. Microcosms with 4 types of substrates were submersed in experimental trenches containing either process water or natural water. Dissolved oxygen, chlorophyll, and biomass standing crop sampling was conducted at intervals throughout a 1-year period. Analysis of variance (ANOVA) was conducted to compare the substrate types. Results of the study will be used to assess the impacts of oil sands process affected materials (OSPM) on benthic biofilm productivity and the initial carbon accumulation process.

  6. Combination of microscopic techniques reveals a comprehensive visual impression of biofilm structure and composition

    DEFF Research Database (Denmark)

    Alhede, Morten; Qvortrup, Klaus; Liebrechts, Ramon

    2012-01-01

    Bacterial biofilms are imaged by various kinds of microscopy including confocal laser scanning microscopy (CLSM) and scanning electron microscopy (SEM). One limitation of CLSM is its restricted magnification, which is resolved by the use of SEM that provides high-magnification spatial images of how...... the single bacteria are located and interact within the biofilm. However, conventional SEM is limited by the requirement of dehydration of the samples during preparation. As biofilms consist mainly of water, the specimen dehydration might alter its morphology. High magnification yet authentic images...... are important to understand the physiology of biofilms. We compared conventional SEM, Focused Ion Beam (FIB)-SEM and CLSM with SEM techniques [cryo-SEM and environmental-SEM (ESEM)] that do not require dehydration. In the case of cryo-SEM, the biofilm is not dehydrated but kept frozen to obtain high-magnification...

  7. Effects of pesticides and pharmaceuticals on biofilms in a highly impacted river.

    Science.gov (United States)

    Proia, L; Osorio, V; Soley, S; Köck-Schulmeyer, M; Pérez, S; Barceló, D; Romaní, A M; Sabater, S

    2013-07-01

    We investigated the effects of pharmaceuticals and pesticides detected in a Mediterranean river, on fluvial biofilms by translocation experiments performed under controlled conditions. Water was sampled from three sites along a pollution gradient. Biofilms grown in mesocosms containing relatively clean water were translocated to heavily polluted water. Several biofilm descriptors were measured before and after translocations. Fifty-seven pharmaceuticals and sixteen pesticides compounds were detected in river waters. The translocation from less to more polluted site was the most effective. Autotrophic biomass and peptidase increased while phosphatase and photosynthetic efficiency decreased. Multivariate analysis revealed that analgesics and anti-inflammatories significantly affected biofilm responses. Ibuprofen and paracetamol were associated with negative effects on photosynthesis, and with the decrease of the green algae/cyanobacteria ratio, while diclofenac was associated with phosphatase activity. The effects of these emerging compounds on biofilms structure and function may cause important alterations in river ecosystem functioning. Copyright © 2013 Elsevier Ltd. All rights reserved.

  8. Effects of ceftazidime and ciprofloxacin on biofilm formation in Proteus mirabilis rods.

    Science.gov (United States)

    Kwiecińska-Piróg, Joanna; Bogiel, Tomasz; Gospodarek, Eugenia

    2013-10-01

    Proteus mirabilis rods are one of the most commonly isolated species of the Proteus genus from human infections, mainly those from the urinary tract and wounds. They are often related to biofilm structure formation. The bacterial cells of the biofilm are less susceptible to routinely used antimicrobials, making the treatment more difficult. The aim of this study was to evaluate quantitatively the influence of ceftazidime and ciprofloxacin on biofilm formation on the polyvinyl chloride surface by 42 P. mirabilis strains isolated from urine, purulence, wound swab and bedsore samples. It has been shown that ceftazidime and ciprofloxacin at concentrations equal to 1/4, 1/2 and 1 times their MIC values for particular Proteus spp. strains decrease their ability to form biofilms. Moreover, ciprofloxacin at concentrations equal to 1/4, 1/2 and 1 times their MIC values for particular P. mirabilis strains reduces biofilm formation more efficiently than ceftazidime at the corresponding concentration values.

  9. Factors affecting dental biofilm in patients wearing fixed orthodontic appliances

    OpenAIRE

    Mei, Li; Chieng, Joyce; Wong, Connie; Benic, Gareth; Farella, Mauro

    2017-01-01

    Abstract Background The aim of this study is to investigate the amount and the distribution of biofilm in patients wearing fixed appliances and its relation with age, gender, frequency of tooth brushing, and patient motivation. Methods The sample comprised 52 patients (15.5 ± 3.6 years old, 30 females and 22 males) wearing fixed orthodontic appliances. Dental biofilm was assessed using a modified plaque index (PI). A questionnaire was used to collect patient’s information, including gender, a...

  10. Naturally Ocurring Polyphosphate-accumulating Bacteria in Benthic Biofilms

    Science.gov (United States)

    Locke, N. A.; Saia, S. M.; Walter, M. T.; Carrick, H. J.; Buda, A. R.; Regan, J. M.

    2014-12-01

    Polyphosphate accumulating organisms (PAOs), known to store excess phosphorus (P) as polyphosphate (poly-P), influence P transport in the environment. Enhanced biological phosphorus removal (EBPR) from wastewater has long served as a basis to study bacterial PAOs, yet little research has genetically identified similar organisms in natural settings. Aerobic/anaerobic cycles, used to select for PAOs in EBPR, can result from changing environmental conditions such as night/day cycles for benthic biofilms. Benthic biofilms from eight Pennsylvanian streams were studied for naturally-occurring bacterial PAOs similar to those typically found in EBPR systems. PAOs were confirmed in the benthic biofilms by a characteristic yellow fluorescent emission from DAPI staining. Cells containing yellow fluorescence were separated from the rest of the sample using a flow cytometer, resulting in a physically enriched culture of PAOs from the benthic biofilms. Amplicon-based metagenomic sequencing will reveal the phylogeny of bacteria responsible for poly-P accumulation in these benthic biofilms. Sequencing data will be used to develop fluorescent in-situ hybridization (FISH) probes, and hybridizations will be performed on DAPI-stained cells to confirm poly-P accumulation by targeted phylotypes. Identifying PAOs in natural settings is a critical step towards studying environments that support high concentrations of PAOs, serving as significant factors in the P cycle. PAOs can then be connected to P transport models to help understand and mitigate P pollution in agricultural watersheds.

  11. Failed bonded interfaces submitted to microcosm biofilm caries development

    NARCIS (Netherlands)

    Montagner, A.F.; Maske, T.T.; Opdam, N.J.; de Soet, J.J.; Cenci, M.S.; Huysmans, M.C.

    2016-01-01

    Objectives: This study aimed to evaluate the dentin wall carious lesion development of different composite-dentin interfaces in the presence of two adhesive bonding materials in the gaps, using a microcosm biofilm model. Methods: Dentin samples were prepared (10.4 mm2) and restored with a composite

  12. Failed bonded interfaces submitted to microcosm biofilm caries development

    NARCIS (Netherlands)

    Montagner, A.F.; Maske, T.T.; Opdam, N.J.; Soet, J.J. de; Cenci, M.S.; Huysmans, M.C.D.N.J.M.

    2016-01-01

    OBJECTIVES: This study aimed to evaluate the dentin wall carious lesion development of different composite-dentin interfaces in the presence of two adhesive bonding materials in the gaps, using a microcosm biofilm model. METHODS: Dentin samples were prepared (10.4mm(2)) and restored with a composite

  13. Biofilm production and antibiotic susceptibility profile of Escherichia ...

    African Journals Online (AJOL)

    In the present study, Escherichia coli strains were isolated from water, stool, sputum and urine samples from HIV and AIDS patients attending treatment centers in the Limpopo Province, using standard microbiological procedures and identified by polymerase chain reaction (PCR). Biofilm assay was performed using the ...

  14. Bacterial biofilms and antibiotic resistance

    Directory of Open Access Journals (Sweden)

    Liliana Caldas-Arias

    2015-04-01

    Full Text Available Biofilms give to bacteria micro-environmental benefits; confers protection against antimicrobials. Bacteria have antibiotic resistance by conventional and unusual mechanisms leading to delayed wound healing, to increase recurrent chronic infections and nosocomial contamination of medical devices. Objective: This narrative review aims to introduce the characteristics of Bacteria-biofilms, antimicrobial resistance mechanisms and potential alternatives for prevention and control of its formation. Methods: Search strategy was performed on records: PubMed / Medline, Lilacs, Redalyc; with suppliers such as EBSCO and thesaurus MeSH and DeCS. Conclusions: Knowledge and research performance of biofilm bacteria are relevant in the search of technology for detection and measuring sensitivity to antibiotics. The identification of Bacterial-biofilms needs no-traditional microbiological diagnosis.

  15. Nanotechnology: Role in dental biofilms

    Directory of Open Access Journals (Sweden)

    Bhardwaj Sonia

    2009-01-01

    Full Text Available Biofilms are surface- adherent populations of microorganisms consisting of cells, water and extracellular matrix material Nanotechnology is promising field of science which can guide our understanding of the role of interspecies interaction in the development of biofilm. Streptococcus mutans with other species of bacteria has been known to form dental biofilm. The correlation between genetically modified bacteria Streptococcus mutans and nanoscale morphology has been assessed using AFMi.e atomic force microscopy. Nanotechnology application includes 16 O/ 18 O reverse proteolytic labeling,use of quantum dots for labeling of bacterial cells, selective removal of cariogenic bacteria while preserving the normal oral flora and silver antimicrobial nanotechnology against pathogens associated with biofilms. The future comprises a mouthwash full of smart nanomachines which can allow the harmless flora of mouth to flourish in a healthy ecosystem

  16. Biofilm formation by Acinetobacter baumannii.

    Science.gov (United States)

    Vidal, R; Dominguez, M; Urrutia, H; Bello, H; Gonzalez, G; Garcia, A; Zemelman, R

    1996-01-01

    Acinetobacter baumannii, an important nosocomial pathogen is usually found on various surfaces in the hospital environment. In this work, the ability to form biofilms on the surface of sterile coverslips by one clinical isolate of A. baumannii was studied. Sessile cells which adhered to coverslips after being immersed in a nutrient-deficient mineral medium were observed by epifluorescence and scanning electron microscopy at various times of incubation. A rapid increase in the number of sessile cells in young biofilms, followed by a slower increase of such cells was found. At 48 h biofilms were clearly visible and an amorphous material similar to the exopolysaccharide described in some other bacteria covered sessile cells was evident. Biofilm formation by A. baumannii probably favours its maintenance on solid surfaces in the hospital environment and protects the micro-organism against some antibacterial factors.

  17. Antibiotic resistance of bacterial biofilms

    DEFF Research Database (Denmark)

    Hoiby, N.; Bjarnsholt, T.; Givskov, M.

    2010-01-01

    A biofilm is a structured consortium of bacteria embedded in a self-produced polymer matrix consisting of polysaccharide, protein and DNA. Bacterial biofilms cause chronic infections because they show increased tolerance to antibiotics and disinfectant chemicals as well as resisting phagocytosis....... Characteristically, gradients of nutrients and oxygen exist from the top to the bottom of biofilms and these gradients are associated with decreased bacterial metabolic activity and increased doubling times of the bacterial cells; it is these more or less dormant cells that are responsible for some of the tolerance...... to antibiotics. Biofilm growth is associated with an increased level of mutations as well as with quorum-sensing-regulated mechanisms. Conventional resistance mechanisms such as chromosomal beta-lactamase, upregulated efflux pumps and mutations in antibiotic target molecules in bacteria also contribute...

  18. Biogenesis of Enterococcis faecium biofilms

    NARCIS (Netherlands)

    Paganelli, F.L.

    2015-01-01

    Nosocomial infections caused by Enterococcus faecium have rapidly increased worldwide and treatment options become more limited. The presence of antibiotic resistance genes and virulence factors in pathogenic E. faecium contribute to difficult-to-treat infections, frequently biofilm mediated, such

  19. Periodontal microbiota of Sardinian children: comparing 200-year-old samples to present-day ones

    Directory of Open Access Journals (Sweden)

    Germano Orrù

    2017-02-01

    Full Text Available Introduction: The microrganisms of the human oral cavity include more than 700 species or phenotypes of bacteria. Some “diseases of civilization” are strictly correlated to changes in the microbiome following the food revolution that occurred after WWII. For that reason, a precise recognition of the microbiome profile before and after this period should be useful to determine the health-compatible model of microbiome. The aim of this study was to compare the microbiome profiles (number of total cells, and pathogen types of dental samples obtained from two distinct groups of children, a 200-year-old retrieved one and a present one.Methods: Two different groups of samples have been studied. The first group was a set of 50 recent subgingival plaque samples obtained from children of age 2-8 years, 14 males and 36 females. They were enrolled by the Department of Dental Disease Prevention (University of Cagliari, in Sardinia, Italy during standard dental care procedures. None reported periodontal disease and none had been under antibiotic therapy during the previous 6 months. The second group was an old retrieved group that included 24 teeth from 6 different 6- to 8-year-old crania fragments; they were obtained from a 200-year-old charnel-house located in Villaputzu, a city close to Cagliari. Representative periodontal bacteria have been identified by a previously published real-time PCR procedure (Sokransky et al., 1998 in which P. gingivalis and T. forsythia (red complex, A. actinomycetemcomitans (green complex and F. nucleatum (orange complex were detected. In addition, the title of each pathogen was expressed as a percentage of the total bacteria (biofilm in the sample.Results and discussion: The profile of periodontal microbiomes, between recent/ancient samples showed a significant difference relative to Sokransky’s red complex bacteria (p < 0.05. In all analyzed periodontal strains, the pathogenic bacteria P. gingivalis and T. forsythia

  20. Biofilms in orthopedic infections: a review of laboratory methods.

    Science.gov (United States)

    Dibartola, Alex C; Swearingen, Matthew C; Granger, Jeffrey F; Stoodley, Paul; Dusane, Devendra H

    2017-04-01

    Bacterial infection after hardware implantation in orthopedic surgery is a devastating issue as it often necessitates increased hospital costs and stays, multiple revision surgeries, and prolonged use of antibiotics. Because of the nature of hardware implantation into the body, these infections are commonly in the form of attached biofilms. The current literature on a range of methodologies to study clinically explanted infected orthopedic hardware, with potential biofilm, in the laboratory setting is limited. General methods include traditional and advanced culturing techniques, microscopy imaging techniques, and techniques that manipulate genetic material. The future of diagnostic techniques for infected implants, innovative hardware design, and treatment solutions for patients all depend on the successful evaluation and characterization of clinical samples in the laboratory setting. This review provides an overview of current methods to study biofilms associated with orthopedic infections and insight into future directions in the field. © 2017 APMIS. Published by John Wiley & Sons Ltd.

  1. High-throughput dental biofilm growth analysis for multiparametric microenvironmental biochemical conditions using microfluidics.

    Science.gov (United States)

    Lam, Raymond H W; Cui, Xin; Guo, Weijin; Thorsen, Todd

    2016-04-26

    Dental biofilm formation is not only a precursor to tooth decay, but also induces more serious systematic health problems such as cardiovascular disease and diabetes. Understanding the conditions promoting colonization and subsequent biofilm development involving complex bacteria coaggregation is particularly important. In this paper, we report a high-throughput microfluidic 'artificial teeth' device offering controls of multiple microenvironmental factors (e.g. nutrients, growth factors, dissolved gases, and seeded cell populations) for quantitative characteristics of long-term dental bacteria growth and biofilm development. This 'artificial teeth' device contains multiple (up to 128) incubation chambers to perform parallel cultivation and analyses (e.g. biofilm thickness, viable-dead cell ratio, and spatial distribution of multiple bacterial species) of bacteria samples under a matrix of different combinations of microenvironmental factors, further revealing possible developmental mechanisms of dental biofilms. Specifically, we applied the 'artificial teeth' to investigate the growth of two key dental bacteria, Streptococci species and Fusobacterium nucleatum, in the biofilm under different dissolved gas conditions and sucrose concentrations. Together, this high-throughput microfluidic platform can provide extended applications for general biofilm research, including screening of the biofilm properties developing under combinations of specified growth parameters such as seeding bacteria populations, growth medium compositions, medium flow rates and dissolved gas levels.

  2. Genotypic diversity of S. mutans in dental biofilm formed in situ under sugar stress exposure.

    Science.gov (United States)

    Arthur, Rodrigo Alex; Tabchoury, Cínthia Pereira Machado; Mattos-Graner, Renata de Oliveira; Del Bel Cury, Altair A; Paes Leme, Adriana Franco; Vale, Gláuber Campos; Cury, Jaime Aparecido

    2007-01-01

    In situ dental biofilm composition under sugar exposure is well known, but sugar effect on the genotypic diversity of S. mutans in dental biofilm has not been explored. This study evaluated S. mutans genotypic diversity in dental biofilm formed in situ under frequent exposure to sucrose and its monosaccharide constituents (glucose and fructose). Saliva of 7 volunteers was collected for isolation of S. mutans and the same volunteers wore intraoral palatal appliances, containing enamel slabs, which were submitted to the following treatments: distilled and deionized water (negative control), 10% glucose + 10% fructose (fermentable carbohydrates) solution or 20% sucrose (fermentable and EPS inductor) solution, 8x/day. After 3, 7 and 14 days, the biofilms were collected and S. mutans colonies were isolated. Arbitrarily primed polymerase chain reaction (AP-PCR) of S. mutans showed that salivary genotypes were also detected in almost all biofilm samples, independently of the treatment, and seemed to reflect those genotypes present at higher proportion in biofilms. In addition to the salivary genotypes, others were found in biofilms but in lower proportions and were distinct among treatment. The data suggest that the in situ model seems to be useful to evaluate genotypic diversity of S. mutans, but, under the tested conditions, it was not possible to clearly show that specific genotypes were selected in the biofilm due to the stress induced by sucrose metabolism or simple fermentation of its monosaccharides.

  3. Portable hyperspectral fluorescence imaging system for detection of biofilms on stainless steel surfaces

    Science.gov (United States)

    Jun, Won; Lee, Kangjin; Millner, Patricia; Sharma, Manan; Chao, Kuanglin; Kim, Moon S.

    2008-04-01

    A rapid nondestructive technology is needed to detect bacterial contamination on the surfaces of food processing equipment to reduce public health risks. A portable hyperspectral fluorescence imaging system was used to evaluate potential detection of microbial biofilm on stainless steel typically used in the manufacture of food processing equipment. Stainless steel coupons were immersed in bacterium cultures, such as E. coli, Pseudomonas pertucinogena, Erwinia chrysanthemi, and Listeria innocula. Following a 1-week exposure, biofilm formations were assessed using fluorescence imaging. In addition, the effects on biofilm formation from both tryptic soy broth (TSB) and M9 medium with casamino acids (M9C) were examined. TSB grown cells enhance biofilm production compared with M9C-grown cells. Hyperspectral fluorescence images of the biofilm samples, in response to ultraviolet-A (320 to 400 nm) excitation, were acquired from approximately 416 to 700 nm. Visual evaluation of individual images at emission peak wavelengths in the blue revealed the most contrast between biofilms and stainless steel coupons. Two-band ratios compared with the single-band images increased the contrast between the biofilm forming area and stainless steel coupon surfaces. The 444/588 nm ratio images exhibited the greatest contrast between the biofilm formations and stainless coupon surfaces.

  4. Role of Non Albicans Candida Spp. and Biofilm in Neonatal ICU.

    Science.gov (United States)

    Goel, Shagun; Mittal, Seema; Chaudhary, Uma

    2016-01-01

    Candida spp. remains the fungal species most commonly associated with biofilm formation. Increase in Candida infections in last decades has almost paralleled the increase and wide spread use of a broad range of medical implant devices mainly in population with impaired host defences. One of the most important characteristics of biofilms is their high level of resistance to antimicrobial drugs. This study was conducted to know the prevalence of different Candida spp. causing blood stream infections and ability to form biofilm and to evaluate the co relation of biofilm with antifungal drug resistance. The present study was conducted on 12464 blood samples for the identification and speciation of various Candida spp. causing blood stream infection over a period of one year. Antifungal susceptibility was performed as per clinical laboratory standard institute guidelines and biofilm formation was detected by method described by Christensen's et al. Out of total 12464 blood culture received, 1378 (11.05%) were culture positive rest and among culture positive 100 (7.25%) Candida isolates were recovered. C. tropicalis was the commonest (43%) species followed by C. albicans (41%), C. krusei (9%) and C. parapsilosis (7%). A total of 41 Candida isolates were biofilm producers and rest 59 isolates were non-biofilm producers. A changing trend of increased prevalence of non albicans Candida spp. was observed which were resistant to commonly used antifungal fluconazole. Multi drug resistance was more common in biofilm forming Candida isolates.

  5. Biogenesis of Enterococcis faecium biofilms

    OpenAIRE

    Paganelli, F.L.

    2015-01-01

    Nosocomial infections caused by Enterococcus faecium have rapidly increased worldwide and treatment options become more limited. The presence of antibiotic resistance genes and virulence factors in pathogenic E. faecium contribute to difficult-to-treat infections, frequently biofilm mediated, such as artificial-medical-device-associated infections. Biofilm is defined as a population of bacteria, encased in an extracellular matrix, attached to biotic surfaces, such as plants, animals and the h...

  6. Bacterial interactions in dental biofilm

    OpenAIRE

    Huang, Ruijie; Li, Mingyun; Gregory, Richard L

    2011-01-01

    Biofilms are masses of microorganisms that bind to and multiply on a solid surface, typically with a fluid bathing the microbes. The microorganisms that are not attached but are free-floating in an aqueous environment are termed planktonic cells. Traditionally, microbiology research has addressed results from planktonic bacterial cells. However, many recent studies have indicated that biofilms are the preferred form of growth of most microbes and particularly those of a pathogenic nature. Bio...

  7. Critical review on biofilm methods

    DEFF Research Database (Denmark)

    Azeredo, Joana; F. Azevedo, Nuno; Briandet, Romain

    2017-01-01

    Biofilms are widespread in nature and constitute an important strategy implemented by microorganisms to survive in sometimes harsh environmental conditions. They can be beneficial or have a negative impact particularly when formed in industrial settings or on medical devices. As such, research in...... and limitations of several methods. Accordingly, this review aims at helping scientists in finding the most appropriate and up-to-date methods to study their biofilms....

  8. The synergistic effect of ultrasonic activation and irrigation on Enterococcus faecalis biofilm

    Directory of Open Access Journals (Sweden)

    Abeer A Al-Mahdi

    2016-01-01

    Full Text Available Aim: The aim of this investigation was to compare the efficacy of passive ultrasonic irrigation (PUI with either 2.5% sodium hypochlorite (NaOCl or saline, with that of conventional syringe irrigation on intraradicular Enterococcus faecalis biofilm. Materials and Methods: Biofilms of E. faecalis were established over 21 days in 80 single roots that had undergone biomechanical preparation followed by gamma radiation. Biofilms were treated for 1 min with 2.5% NaOCl/PUI (Group 1, 2.5% NaOCl (Group 2, sterile saline/PUI (Group 3, and sterile saline (Group 4. The positive control (n = 4 was used to confirm the presence of biofilm before various treatments. Additional four samples that served as a negative control were used to confirm the sterility of the samples. Biofilm eradication was evaluated by Colony Forming Unit (CFU quantification and scanning electron microscopy (SEM. Results: The median of CFUs of S1 was significantly higher than that of S2 in all experimental groups. SEM examination showed a significant difference between the positive control and the experimental groups (P < 0.001, with the highest score of biofilm in the positive control group followed by Group 4 and both groups were not statistically significant from each other (P = 0.067. Following various treatments, the highest scores of biofilm were observed in the coronal third and the least were in the apical third. Conclusions: PUI did not increase the effectiveness of NaOCl irrigation on biofilm removal, however, PUI enhanced biofilm disturbance when used with saline. The least mean score of remaining biofilm was in the apical third of all treatment groups compared to other thirds.

  9. Chlorhexidine Substantivity on Salivary Flora and Plaque-Like Biofilm: An In Situ Model

    Science.gov (United States)

    García-Caballero, Lucía; Quintas, Victor; Prada-López, Isabel; Seoane, Juan; Donos, Nikos; Tomás, Inmaculada

    2013-01-01

    Objective To evaluate the in situ antibacterial activity of a mouthrinse with 0.2% Chlorhexidine (M-0.2% CHX) on undisturbed de novo plaque-like biofilm (PL-biofilm) and on salivary flora up to 7 hours after its application. Methods A special acrylic appliance was designed, with 3 inserted glass disks on each buccal side, allowing for PL-biofilm growth. Fifteen healthy volunteers wore the appliance for 48 hours and then performed an M-0.2% CHX; disks were removed at 30 seconds and 1, 3, 5 and 7 hours after the mouth-rinsing. Applying a washout period, saliva samples were collected from each volunteer at 30 seconds and 1, 3, 5 and 7 hours after performing an M-0.2% CHX. The PL-biofilm and saliva samples were analysed by confocal laser scanning and epifluorescence microscopes, respectively. Results At 30 seconds after M-0.2% CHX, the levels of viable bacteria detected in saliva were significantly lower than those observed in PL-biofilm. The difference in the percentage of live bacteria detected in saliva was significantly higher than that observed in PL-biofilm at 5 and 7 hours after M-0.2% CHX. Conclusion After a single mouthrinse of the 0.2% CHX formulation tested in the present study, the 2-day PL-biofilm presented a significantly higher resistance to this antiseptic in situ than that observed in salivary flora. However, this 0.2% CHX formulation showed a higher substantivity on PL-biofilm than on salivary flora at 5 and 7 hours after mouth-rinsing, which could be related to the slower growth rate of PL-biofilm and the possible reservoir function for antimicrobial agents associated with the undisturbed de novo PL-biofilm. PMID:24386220

  10. Efficacy of a marine bacterial nuclease against biofilm forming microorganisms isolated from chronic rhinosinusitis.

    Directory of Open Access Journals (Sweden)

    Robert C Shields

    Full Text Available BACKGROUND: The persistent colonization of paranasal sinus mucosa by microbial biofilms is a major factor in the pathogenesis of chronic rhinosinusitis (CRS. Control of microorganisms within biofilms is hampered by the presence of viscous extracellular polymers of host or microbial origin, including nucleic acids. The aim of this study was to investigate the role of extracellular DNA in biofilm formation by bacteria associated with CRS. METHODS/PRINCIPAL FINDINGS: Obstructive mucin was collected from patients during functional endoscopic sinus surgery. Examination of the mucous by transmission electron microscopy revealed an acellular matrix punctuated occasionally with host cells in varying states of degradation. Bacteria were observed in biofilms on mucosal biopsies, and between two and six different species were isolated from each of 20 different patient samples. In total, 16 different bacterial genera were isolated, of which the most commonly identified organisms were coagulase-negative staphylococci, Staphylococcus aureus and α-haemolytic streptococci. Twenty-four fresh clinical isolates were selected for investigation of biofilm formation in vitro using a microplate model system. Biofilms formed by 14 strains, including all 9 extracellular nuclease-producing bacteria, were significantly disrupted by treatment with a novel bacterial deoxyribonuclease, NucB, isolated from a marine strain of Bacillus licheniformis. Extracellular biofilm matrix was observed in untreated samples but not in those treated with NucB and extracellular DNA was purified from in vitro biofilms. CONCLUSION/SIGNIFICANCE: Our data demonstrate that bacteria associated with CRS form robust biofilms which can be reduced by treatment with matrix-degrading enzymes such as NucB. The dispersal of bacterial biofilms with NucB may offer an additional therapeutic target for CRS sufferers.

  11. Oral hygiene frequency and presence of visible biofilm in the primary dentition.

    Science.gov (United States)

    Santos, Ana Paula Pires dos; Séllos, Mariana Canano; Ramos, Maria Eliza Barbosa; Soviero, Vera Mendes

    2007-01-01

    The purpose of this study was to associate oral hygiene frequency and presence of visible biofilm in the primary dentition. The sample consisted of 90 children, aged up to 4 years old, outpatients of the University Hospital of the Rio de Janeiro State University. The examinations were carried out in a dental office by a single trained examiner who was aided by an assistant. The parents answered a structured questionnaire about oral hygiene methods and frequency. Two biofilm indices, one simplified (BF1) and the other conventional (BF2), were used. BF1 classifies biofilm as absent, thin or thick, in anterior and/or posterior teeth, and provides a score for the patient, whereas BF2 classifies biofilm as absent or present, provides scores for three surfaces of each tooth and the final score is the percentage of tooth surfaces with biofilm. More than half of the parents (51 - 56.7%) reported they cleaned their child's teeth at least twice a day, while 7 (7.8%) had never cleaned their child's teeth. BF1 revealed that 12.2% (11) of the children had no visible biofilm, 37.8% (34) had thin biofilm in anterior and/or posterior teeth, 27.8% (25) had thick biofilm in anterior or posterior teeth and 22.2% (20) had thick biofilm in both anterior and posterior teeth. BF2 revealed a mean value of 21.8% (s.d. 16.5). No statistically significant correlations were found between oral hygiene frequency and the two biofilm indices (p > 0.05), indicating that oral hygiene frequency was not associated to oral hygiene quality in the evaluated sample.

  12. Bacterial resistance in biofilm-associated bacteria.

    Science.gov (United States)

    Venkatesan, Nandakumar; Perumal, Govindaraj; Doble, Mukesh

    2015-01-01

    Biofilms are structured groups of different bacterial species that are responsible for most chronic and recurrent infections. Biofilm-related infections reoccur in approximately 65-80% of cases. Bacteria associated with the biofilm are highly resistant to antibiotics. Knowledge of biofilm formation, its propagation and the resistance associated with it is scant and a multidisciplinary approach is followed to understand the science and develop strategies to address this problem. This article discusses the role of various biochemical factors, molecular mechanisms and altered host environment causes associated with bacterial resistance in biofilm. It also reveals the target sites and different multidisciplinary strategies adapted for destroying or preventing the formation of biofilms.

  13. NOSOCOMIAL INFECTION AND MICROBIAL BIOFILMS IN SURGERY

    Directory of Open Access Journals (Sweden)

    N. I. Gabrielyan

    2012-01-01

    Full Text Available The review presents data on the role of biofilms formation by opportunistic microbes in surgery. It gives in- formation about the microbial structure of biofilms, their architecture and physiology. The attention was payed to significal importance of microbial communities, which form biofilms in surgery. Mechanisms of increased resistance of biofilms bacteria are compared with plankton. The review includes literature data on the process of formation biofilms on intravascular catheters and methods of inhibition and protection. Methods of studing formation and inhibition of biofilms in vitro and in vivo are presented. Different biotechnology methods, based on using antiadhesive, antiseptic, biophysical resources and biomaterials are discussed. 

  14. Cariogenic effects of probiotic Lactobacillus rhamnosus GG in a dental biofilm model.

    Science.gov (United States)

    Schwendicke, F; Dörfer, C; Kneist, S; Meyer-Lueckel, H; Paris, S

    2014-01-01

    Probiotic bacteria have been suggested to inhibit Streptococcus mutans (SM) and thus prevent dental caries. However, supporting evidence is weak and probiotic species might be cariogenic themselves. Thus, we compared and combined the probiotic Lactobacillus rhamnosus GG (LGG) with SM and analysed the resulting mineral loss (ΔZ) in dental tissues. We simulated three biofilm compositions (SM, LGG, SM × LGG), two lesion sites (smooth enamel, dentin cavity) and two nutrition supply frequencies (twice/day, 6 times/day) in a multi-station, continuous-culture biofilm model. A total of 240 bovine enamel and dentin samples were cut, polished and embedded. All experimental procedures were performed in independent duplicates, with 10 samples being allocated to each group for each experiment (final sample size n = 20/group). Biofilms were cultured on the specimens and supplied with 2% sucrose medium and artificial saliva in consecutive pulses. After 10 days, ΔZ and bacterial numbers were assessed. SM × LGG biofilms caused significantly increased ΔZ compared with SM or LGG biofilms (p biofilms of different species (p > 0.05, ANOVA). Frequent nutrition supply significantly increased bacterial numbers (p Biofilms in dentin cavities compared to smooth enamel harboured significantly more bacteria (p < 0.05). LGG induced mineral loss especially in dentin cavities and under highly cariogenic conditions. LGG did not have inhibitory effects on SM, but rather contributed to the caries process in vitro.

  15. Biochemical composition of the saliva and dental biofilm of children with Down syndrome.

    Science.gov (United States)

    Schwertner, Carolina; Moreira, Maurício José Santos; Faccini, Lavinia Schuler; Hashizume, Lina Naomi

    2016-03-01

    The biochemical composition of the saliva and biofilm of children with Down syndrome (DS) may be associated with the incidence of caries in this population. To evaluate the biochemical composition of the saliva and dental biofilm of children with DS in the city of Porto Alegre, RS. The sample comprised 144 children between 6 and 14 years of age, of whom 61 had DS and 83 did not. Stimulated saliva samples were collected from all participants, as were samples of 48-h biofilm. Fluoride (F), calcium (Ca), and phosphorus (Pi ) concentrations in saliva and biofilm were determined by colorimetric method (Ca and Pi ) or selective electrode (F). The level of insoluble extracellular polysaccharide (EPS) in dental biofilm was measured using sulphuric acid method. Salivary concentration of F, Ca, and Pi did not differ between children with and without DS. The dental biofilm of children with DS, however, showed higher Pi and EPS levels than that of children without the syndrome (P dental biofilm of children with DS has higher cariogenic potential than that of children without this condition. © 2015 BSPD, IAPD and John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  16. Interspecies interactions result in enhanced biofilm formation by co-cultures of bacteria isolated from a food processing environment

    DEFF Research Database (Denmark)

    Røder, Henriette Lyng; Raghupathi, Prem Krishnan; Herschend, Jakob

    2015-01-01

    Bacterial attachment and biofilm formation can lead to poor hygienic conditions in food processing environments. Furthermore, interactions between different bacteria may induce or promote biofilm formation. In this study, we isolated and identified a total of 687 bacterial strains from seven...... examined for multispecies biofilm formation. Eight strains from each sampling site were chosen and all possible combinations of four member co-cultures were tested for enhanced biofilm formation at 15°C and 24°C. In approximately 20% of the multispecies consortia grown at 15°C, the biofilm formation...... was enhanced when comparing to monospecies biofilms. Two specific isolates (one from each location) were found to be present in synergistic combinations with higher frequencies than the remaining isolates tested. This data provides insights into the ability of co-localized isolates to influence co-culture...

  17. Bacterial Biofilms as Complex Communities

    Science.gov (United States)

    Vlamakis, Hera

    2010-03-01

    Many microbial populations form surface-associated multicellular communities known as biofilms. These multicellular communities are encased in a self-produced extracellular matrix composed of polysaccharides and proteins. Division of labor is a key feature of these communities and different cells serve distinct functions. We have found that in biofilms of the bacterium Bacillus subtilis, different cell types including matrix-producing and sporulating cells coexist and localize to distinct regions within the structured community. We were interested in understanding how these different cell types arise. Using fluorescence reporters under the control of promoters that are specific for distinct cell types we were able to follow the dynamics of differentiation throughout biofilm development. We found that a series of extracellular signals leads to differentiation of distinct cell types during biofilm formation. In addition, we found that extracellular matrix functions as a differentiation signal for timely sporulation within a biofilm and mutants unable to produce matrix were delayed in sporulation. Our results indicate that within a biofilm, cell-cell signaling is directional in that one cell type produces a signal that is sensed by another distinct cell type. Furthermore, once differentiated, cells become resistant to the action of other signaling molecules making it possible to maintain distinct cell populations over prolonged periods.

  18. Plasticity of Candida albicans Biofilms

    Science.gov (United States)

    Daniels, Karla J.

    2016-01-01

    SUMMARY Candida albicans, the most pervasive fungal pathogen that colonizes humans, forms biofilms that are architecturally complex. They consist of a basal yeast cell polylayer and an upper region of hyphae encapsulated in extracellular matrix. However, biofilms formed in vitro vary as a result of the different conditions employed in models, the methods used to assess biofilm formation, strain differences, and, in a most dramatic fashion, the configuration of the mating type locus (MTL). Therefore, integrating data from different studies can lead to problems of interpretation if such variability is not taken into account. Here we review the conditions and factors that cause biofilm variation, with the goal of engendering awareness that more attention must be paid to the strains employed, the methods used to assess biofilm development, every aspect of the model employed, and the configuration of the MTL locus. We end by posing a set of questions that may be asked in comparing the results of different studies and developing protocols for new ones. This review should engender the notion that not all biofilms are created equal. PMID:27250770

  19. Factors affecting dental biofilm in patients wearing fixed orthodontic appliances

    Directory of Open Access Journals (Sweden)

    Li Mei

    2017-01-01

    Full Text Available Abstract Background The aim of this study is to investigate the amount and the distribution of biofilm in patients wearing fixed appliances and its relation with age, gender, frequency of tooth brushing, and patient motivation. Methods The sample comprised 52 patients (15.5 ± 3.6 years old, 30 females and 22 males wearing fixed orthodontic appliances. Dental biofilm was assessed using a modified plaque index (PI. A questionnaire was used to collect patient’s information, including gender, age, treatment motivation, and frequency of tooth brushing. Results Gingival (PI score = 0.9 ± 0.7, mesial (0.8 ± 0.6, and distal (0.8 ± 0.5 areas accumulated more biofilm than occlusal areas (0.3 ± 0.3 (P < 0.038. The maxillary lateral incisors (1.1 ± 0.8 and maxillary canines (1.0 ± 0.8 had more biofilm than other teeth (P < 0.05. The maxillary arch (0.8 ± 0.7 had significantly more biofilm than mandibular arch (0.6 ± 0.6 (P = 0.042. No significant difference was found between the right side (0.7 ± 0.7 and left side (0.7 ± 0.6 (P = 0.627. Less biofilm was found in females (0.6 ± 0.5, adults (0.3 ± 0.3, and “self-motivated” patients (0.3 ± 0.3, compared with males (0.9 ± 0.5, children (0.8 ± 0.6, and “family-motivated” patients (1.1 ± 0.5 (P < 0.001. The amount of biofilm was associated with self-report of the frequency of daily tooth brushing (P < 0.001. Conclusions Patients wearing fixed orthodontic appliances have the highest biofilm accumulation on the maxillary lateral incisors and maxillary canines, particularly in the gingival area and areas behind arch wires. Less biofilm was observed in female and adult patients and in those who were self-motivated and brushed their teeth more often.

  20. Factors affecting dental biofilm in patients wearing fixed orthodontic appliances.

    Science.gov (United States)

    Mei, Li; Chieng, Joyce; Wong, Connie; Benic, Gareth; Farella, Mauro

    2017-12-01

    The aim of this study is to investigate the amount and the distribution of biofilm in patients wearing fixed appliances and its relation with age, gender, frequency of tooth brushing, and patient motivation. The sample comprised 52 patients (15.5 ± 3.6 years old, 30 females and 22 males) wearing fixed orthodontic appliances. Dental biofilm was assessed using a modified plaque index (PI). A questionnaire was used to collect patient's information, including gender, age, treatment motivation, and frequency of tooth brushing. Gingival (PI score = 0.9 ± 0.7), mesial (0.8 ± 0.6), and distal (0.8 ± 0.5) areas accumulated more biofilm than occlusal areas (0.3 ± 0.3) (P biofilm than other teeth (P biofilm than mandibular arch (0.6 ± 0.6) (P = 0.042). No significant difference was found between the right side (0.7 ± 0.7) and left side (0.7 ± 0.6) (P = 0.627). Less biofilm was found in females (0.6 ± 0.5), adults (0.3 ± 0.3), and "self-motivated" patients (0.3 ± 0.3), compared with males (0.9 ± 0.5), children (0.8 ± 0.6), and "family-motivated" patients (1.1 ± 0.5) (P biofilm was associated with self-report of the frequency of daily tooth brushing (P biofilm accumulation on the maxillary lateral incisors and maxillary canines, particularly in the gingival area and areas behind arch wires. Less biofilm was observed in female and adult patients and in those who were self-motivated and brushed their teeth more often.

  1. Effect of engineered environment on microbial community structure in biofilter and biofilm on reverse osmosis membrane.

    Science.gov (United States)

    Jeong, Sanghyun; Cho, Kyungjin; Jeong, Dawoon; Lee, Seockheon; Leiknes, TorOve; Vigneswaran, Saravanamuthu; Bae, Hyokwan

    2017-11-01

    Four dual media filters (DMFs) were operated in a biofiltration mode with different engineered environments (DMF I and II: coagulation with/without acidification and DMF III and IV: without/with chlorination). Designed biofilm enrichment reactors (BERs) containing the removable reverse osmosis (RO) coupons, were connected at the end of the DMFs in parallel to analyze the biofilm on the RO membrane by DMF effluents. Filtration performances were evaluated in terms of dissolved organic carbon (DOC) and assimilable organic carbon (AOC). Organic foulants on the RO membrane were also quantified and fractionized. The bacterial community structures in liquid (seawater and effluent) and biofilm (DMF and RO) samples were analyzed using 454-pyrosequencing. The DMF IV fed with the chlorinated seawater demonstrated the highest reductions of DOC including LMW-N as well as AOC among the other DMFs. The DMF IV was also effective in reducing organic foulants on the RO membrane surface. The bacterial community structure was grouped according to the sample phase (i.e., liquid and biofilm samples), sampling location (i.e., DMF and RO samples), and chlorination (chlorinated and non-chlorinated samples). In particular, the biofilm community in the DMF IV differed from the other DMF treatments, suggesting that chlorination exerted as stronger selective pressure than pH adjustment or coagulation on the biofilm community. In the DMF IV, several chemoorganotrophic chlorine-resistant biofilm-forming bacteria such as Hyphomonas, Erythrobacter, and Sphingomonas were predominant, and they may enhance organic carbon degradation efficiency. Diverse halophilic or halotolerant organic degraders were also found in other DMFs (i.e., DMF I, II, and III). Various kinds of dominant biofilm-forming bacteria were also investigated in RO membrane samples; the results provided possible candidates that cause biofouling when DMF process is applied as the pretreatment option for the RO process. Copyright

  2. Effect of engineered environment on microbial community structure in biofilter and biofilm on reverse osmosis membrane

    KAUST Repository

    Jeong, Sanghyun

    2017-07-25

    Four dual media filters (DMFs) were operated in a biofiltration mode with different engineered environments (DMF I and II: coagulation with/without acidification and DMF III and IV: without/with chlorination). Designed biofilm enrichment reactors (BERs) containing the removable reverse osmosis (RO) coupons, were connected at the end of the DMFs in parallel to analyze the biofilm on the RO membrane by DMF effluents. Filtration performances were evaluated in terms of dissolved organic carbon (DOC) and assimilable organic carbon (AOC). Organic foulants on the RO membrane were also quantified and fractionized. The bacterial community structures in liquid (seawater and effluent) and biofilm (DMF and RO) samples were analyzed using 454-pyrosequencing. The DMF IV fed with the chlorinated seawater demonstrated the highest reductions of DOC including LMW-N as well as AOC among the other DMFs. The DMF IV was also effective in reducing organic foulants on the RO membrane surface. The bacterial community structure was grouped according to the sample phase (i.e., liquid and biofilm samples), sampling location (i.e., DMF and RO samples), and chlorination (chlorinated and non-chlorinated samples). In particular, the biofilm community in the DMF IV differed from the other DMF treatments, suggesting that chlorination exerted as stronger selective pressure than pH adjustment or coagulation on the biofilm community. In the DMF IV, several chemoorganotrophic chlorine-resistant biofilm-forming bacteria such as Hyphomonas, Erythrobacter, and Sphingomonas were predominant, and they may enhance organic carbon degradation efficiency. Diverse halophilic or halotolerant organic degraders were also found in other DMFs (i.e., DMF I, II, and III). Various kinds of dominant biofilm-forming bacteria were also investigated in RO membrane samples; the results provided possible candidates that cause biofouling when DMF process is applied as the pretreatment option for the RO process.

  3. Biofilm carrier migration model describes reactor performance.

    Science.gov (United States)

    Boltz, Joshua P; Johnson, Bruce R; Takács, Imre; Daigger, Glen T; Morgenroth, Eberhard; Brockmann, Doris; Kovács, Róbert; Calhoun, Jason M; Choubert, Jean-Marc; Derlon, Nicolas

    2017-06-01

    The accuracy of a biofilm reactor model depends on the extent to which physical system conditions (particularly bulk-liquid hydrodynamics and their influence on biofilm dynamics) deviate from the ideal conditions upon which the model is based. It follows that an improved capacity to model a biofilm reactor does not necessarily rely on an improved biofilm model, but does rely on an improved mathematical description of the biofilm reactor and its components. Existing biofilm reactor models typically include a one-dimensional biofilm model, a process (biokinetic and stoichiometric) model, and a continuous flow stirred tank reactor (CFSTR) mass balance that [when organizing CFSTRs in series] creates a pseudo two-dimensional (2-D) model of bulk-liquid hydrodynamics approaching plug flow. In such a biofilm reactor model, the user-defined biofilm area is specified for each CFSTR; thereby, Xcarrier does not exit the boundaries of the CFSTR to which they are assigned or exchange boundaries with other CFSTRs in the series. The error introduced by this pseudo 2-D biofilm reactor modeling approach may adversely affect model results and limit model-user capacity to accurately calibrate a model. This paper presents a new sub-model that describes the migration of Xcarrier and associated biofilms, and evaluates the impact that Xcarrier migration and axial dispersion has on simulated system performance. Relevance of the new biofilm reactor model to engineering situations is discussed by applying it to known biofilm reactor types and operational conditions.

  4. Inferring energy sources in constructed wetlands through stable isotope analysis of microbial biofilms

    Energy Technology Data Exchange (ETDEWEB)

    Jurkowski, K.; Ciborowski, J. [Windsor Univ., ON (Canada); Daly, C. [Suncor Energy, Fort McMurray, AB (Canada)

    2010-07-01

    This study presented a novel method of sequestering the microbial biofilm in constructed wetland ecosystems. Artificial substrates were fixed within 8 wetlands differing in age and construction materials over a 2 year period at oil sands lease sites in northeastern Alberta. Autotrophic and heterotrophic biofilm samples were collected from both the subsurface and epibenthic zones of the pipe surfaces of each submerged substrate assembly. A mixing model of d13C, d15N and d34S isotopic signatures was used to assess the contribution of 4 potential nutrient sources of the biofilm. Samples included dominant living and senescent emergent as well as submergent macrophytes, particulate organic matter, dissolved organic carbon, and invertebrates. The samples were collected to compare the biofilm signatures of each wetland in relation to the heterotrophic processes caused by the assimilation of oil sands-derived hydrocarbons and autochthonous detrital pools.

  5. Presence of a polymicrobial endometrial biofilm in patients with bacterial vaginosis.

    Science.gov (United States)

    Swidsinski, Alexander; Verstraelen, Hans; Loening-Baucke, Vera; Swidsinski, Sonja; Mendling, Werner; Halwani, Zaher

    2013-01-01

    To assess whether the bacterial vaginosis biofilm extends into the upper female genital tract. Endometrial samples obtained during curettage and fallopian tube samples obtained during salpingectomy were collected. Endometrial and fallopian tube samples were analyzed for the presence of bacteria with fluorescence-in-situ-hybridisation (FISH) analysis with probes targeting bacterial vaginosis-associated and other bacteria. A structured polymicrobial Gardnerella vaginalis biofilm could be detected in part of the endometrial and fallopian tube specimens. Women with bacterial vaginosis had a 50.0% (95% CI 24.0-76.0) risk of presenting with an endometrial Gardnerella vaginalis biofilm. Pregnancy (AOR  = 41.5, 95% CI 5.0-341.9, pGardnerella vaginalis biofilm attached to the endometrium. This may have major implications for our understanding of the pathogenesis of adverse pregnancy outcome in association with bacterial vaginosis.

  6. Staphylococcus epidermidis surfactant peptides promote biofilm maturation and dissemination of biofilm-associated infection in mice

    OpenAIRE

    Wang, Rong; Khan, Burhan A.; Cheung, Gordon Y. C.; Bach, Thanh-Huy L.; Jameson-Lee, Max; Kong, Kok-Fai; Queck, Shu Y.; Otto, Michael

    2010-01-01

    Biofilms are surface-attached agglomerations of microorganisms embedded in an extracellular matrix. Biofilm-associated infections are difficult to eradicate and represent a significant reservoir for disseminating and recurring serious infections. Infections involving biofilms frequently develop on indwelling medical devices in hospitalized patients, and Staphylococcus epidermidis is the leading cause of infection in this setting. However, the molecular determinants of biofilm dissemination ar...

  7. Bacterial lysine decarboxylase influences human dental biofilm lysine content, biofilm accumulation, and subclinical gingival inflammation.

    Science.gov (United States)

    Lohinai, Zsolt; Keremi, Beata; Szoko, Eva; Tabi, Tamas; Szabo, Csaba; Tulassay, Zsolt; Levine, Martin

    2012-08-01

    Dental biofilms contain a protein that inhibits mammalian cell growth, possibly lysine decarboxylase from Eikenella corrodens. This enzyme decarboxylates lysine, an essential amino acid for dentally attached cell turnover in gingival sulci. Lysine depletion may stop this turnover, impairing the barrier to bacterial compounds. The aims of this study are to determine biofilm lysine and cadaverine contents before oral hygiene restriction (OHR) and their association with plaque index (PI) and gingival crevicular fluid (GCF) after OHR for 1 week. Laser-induced fluorescence after capillary electrophoresis was used to determine lysine and cadaverine contents in dental biofilm, tongue biofilm, and saliva before OHR and in dental biofilm after OHR. Before OHR, lysine and cadaverine contents of dental biofilm were similar and 10-fold greater than in saliva or tongue biofilm. After 1 week of OHR, the biofilm content of cadaverine increased and that of lysine decreased, consistent with greater biofilm lysine decarboxylase activity. Regression indicated that PI and GCF exudation were positively related to biofilm lysine after OHR, unless biofilm lysine exceeded the minimal blood plasma content, in which case PI was further increased but GCF exudation was reduced. After OHR, lysine decarboxylase activity seems to determine biofilm lysine content and biofilm accumulation. When biofilm lysine exceeds minimal blood plasma content after OHR, less GCF appeared despite more biofilm. Lysine appears important for biofilm accumulation and the epithelial barrier to bacterial proinflammatory agents. Inhibiting lysine decarboxylase may retard the increased GCF exudation required for microbial development and gingivitis.

  8. Clinical efficacy of subgingival debridement with adjunctive erbium:yttrium-aluminum-garnet laser treatment in patients with chronic periodontitis: a randomized clinical trial.

    Science.gov (United States)

    Sanz-Sánchez, Ignacio; Ortiz-Vigón, Alberto; Matos, Rita; Herrera, David; Sanz, Mariano

    2015-04-01

    The efficacy of erbium:yttrium-aluminum-garnet (Er:YAG) laser application as an adjunct to subgingival debridement in the treatment of chronic periodontitis (CP) is controversial. This study assesses the efficacy of combining full-mouth subgingival debridement with Er:YAG laser application in the treatment of patients with CP. In this 12-month, single-masked, parallel-group clinical trial, 40 patients with moderate CP were selected and randomly assigned to a test group (one session of full-mouth ultrasonic subgingival debridement followed 1 week later by Er:YAG application in sites with initial probing depths [PDs] of ≥4.5 mm) and a control group (two sessions of ultrasonic debridement within 1 week). The main outcome variable was change in PD; the secondary outcomes were change in clinical attachment level and proportion of sites with bleeding on probing. Outcomes were assessed at baseline and after 3, 6, and 12 months. Data were analyzed as intention to treat using analysis of variance to assess intergroup differences. Both treatments resulted in significant clinical improvements. The test group achieved, in comparison with the control, a significantly lower percentage of sites with PD ≥4.5 mm (17.44% versus 22.83%, respectively; P = 0.004) and a tendency for a lower percentage of sites with PD ≥4.5 mm and bleeding on probing (9.78% versus 12.69%; P = 0.052). This limited added clinical effect may justify the use of a protocol combining full-mouth ultrasonic debridement with laser therapy in the treatment of initial moderate CP.

  9. Comparison of the efficacy of subgingival irrigation with 2% povidone-iodine and tetracycline HCl in subjects with chronic moderate periodontitis: A clinico microbiological study.

    Science.gov (United States)

    Perayil, Jayachandran; Menon, Keerthy S; Biswas, Raja; Fenol, Angel; Vyloppillil, Rajesh

    2016-01-01

    This study was performed to evaluate and compare the clinical and antimicrobial efficacy of subgingival irrigation with tetracycline and povidone-iodine as an adjunct to nonsurgical periodontal therapy. Twenty subjects with chronic moderate periodontitis were recruited in this split-mouth study with probing pocket depth of >3 and ≤5 mm and clinical attachment loss of 3-4 mm in relation to 16, 36, and 46. In each subject, three selected periodontal pockets were assigned to receive one out of three irrigants (1) sterile water (control) in 16; (2) tetracycline at 10 mg/ml in 36; (3) 2% povidone-iodine in 46, and these sites were designated as Group A, Group B, and Group C, respectively. Plaque score, gingival score, pocket probing depth, and clinical attachment level were evaluated before treatment and at 1 and 3 months posttreatment. Multiplex polymerase chain reaction was used to detect Porphyromonas gingivalis and Tannerella forsythensis which have been implicated as the major risk factors for periodontal disease. Subgingival plaque collected before treatment and at 1 and 3 months posttreatment. Data were analysed using ANOVA and repeated measure ANOVA. Results were considered significant if P < 0.05. Clinical and microbiological parameters were reduced posttreatment, the reduction being significantly higher in Group B compared to Group C. It can be concluded that chemical and mechanical therapies were of slight benefit in the treatment of chronic moderate periodontitis, and there was an adjunctive effect of significance when scaling and root planing was combined with a single subgingival irrigation with tetracycline or povidone-iodine in lower concentration.

  10. The sociodemographic characteristics, periodontal health status, and subgingival microbiota of patients with chronic periodontitis and type 2 diabetes mellitus: a case-control study in a Chinese population.

    Science.gov (United States)

    Li, Chen; Liu, Jingbo; Tan, Lisi; Yu, Ning; Lin, Li; Geng, Fengxue; Zhang, Dongmei; Pan, Yaping

    2013-08-01

    In China, chronic periodontitis (CP) is common in patients with type 2 diabetes mellitus (T2DM). The purpose of this study is to identify the sociodemographic characteristics associated with such patients and to assess the periodontal health status and subgingival microbiota of patients with CP and T2DM (T2DMCP) in the Chinese population. A total of 150 patients with T2DMCP and 306 patients with CP without any systemic disease completed questionnaires, underwent clinical periodontal examinations and participated in diabetes-related parameter examinations. Subgingival plaques were obtained to determine the prevalence and amounts of selected oral bacterial species using polymerase chain reaction (PCR) and real-time PCR, respectively. The income level and mean body mass index (BMI) of the patients with T2DMCP were significantly higher than those of the patients with CP. Additionally, the patients with T2DMCP were more likely to be urban residents, and they had significantly more severe periodontitis than did the patients with CP. In the patients with T2DMCP, the prevalence and amounts of Treponema denticola and Tannerella forsythia were significantly higher than those in the patients with CP. Finally, compared with the patients with CP, the patients with T2DMCP had a significantly lower prevalence and amount of Prevotella intermedia. Compared with the patients with CP, the patients with T2DMCP were more likely to be urban residents and generally had higher incomes, higher mean BMI, and poorer periodontal health status. Higher levels of T. denticola and T. forsythia and lower levels of P. intermedia were identified in the subgingival plaque of the patients with T2DMCP.

  11. Comparison of the efficacy of subgingival irrigation with 2% povidone-iodine and tetracycline HCl in subjects with chronic moderate periodontitis: A clinico microbiological study

    Directory of Open Access Journals (Sweden)

    Jayachandran Perayil

    2016-01-01

    Full Text Available Background: This study was performed to evaluate and compare the clinical and antimicrobial efficacy of subgingival irrigation with tetracycline and povidone-iodine as an adjunct to nonsurgical periodontal therapy. Materials and Methods: Twenty subjects with chronic moderate periodontitis were recruited in this split-mouth study with probing pocket depth of >3 and ≤5 mm and clinical attachment loss of 3-4 mm in relation to 16, 36, and 46. In each subject, three selected periodontal pockets were assigned to receive one out of three irrigants (1 sterile water (control in 16; (2 tetracycline at 10 mg/ml in 36; (3 2% povidone-iodine in 46, and these sites were designated as Group A, Group B, and Group C, respectively. Plaque score, gingival score, pocket probing depth, and clinical attachment level were evaluated before treatment and at 1 and 3 months posttreatment. Multiplex polymerase chain reaction was used to detect Porphyromonas gingivalis and Tannerella forsythensis which have been implicated as the major risk factors for periodontal disease. Subgingival plaque collected before treatment and at 1 and 3 months posttreatment. Data were analysed using ANOVA and repeated measure ANOVA. Results were considered significant if P < 0.05. Results: Clinical and microbiological parameters were reduced posttreatment, the reduction being significantly higher in Group B compared to Group C. Conclusion: It can be concluded that chemical and mechanical therapies were of slight benefit in the treatment of chronic moderate periodontitis, and there was an adjunctive effect of significance when scaling and root planing was combined with a single subgingival irrigation with tetracycline or povidone-iodine in lower concentration.

  12. Prevalencia de Cándida y asociación con periodontopatógenos presentes en placa subgingival de pacientes con periodontitis crónica

    OpenAIRE

    C.M. Ardila Medina; M.E. López Gaviria; I.C. Guzmán Zuluaga

    2014-01-01

    Introducción: Pocos estudios han descrito la presencia de levaduras en placa subgingival de pacientes con periodontitis crónica desconociéndose las implicaciones que puede tener su presencia sobre el tratamiento periodontal. Objetivo: El propósito de esta investigación fue evaluar la prevalencia de levaduras en las bolsas periodontales, su influencia sobre los parámetros clínicos y su asociación con otros periodontopatógenos presentes en periodontitis crónica. Materiales y métodos: Se examina...

  13. Differential Recovery of Candida Species from Subgingival Sites in Human Immunodeficiency Virus-Positive and Healthy Children from Rio de Janeiro, Brazil

    Science.gov (United States)

    Portela, M. B.; Souza, I. P. R.; Costa, E. M. M. B.; Hagler, A. N.; Soares, R. M. A.; Santos, A. L. S.

    2004-01-01

    The prevalence of subgingival Candida species was studied in 52 human immunodeficiency virus (HIV)-positive and 42 HIV-negative children. Candida was cultured from 22 (42.3%) and 3 (7.1%) HIV-infected and control children, respectively. C. albicans was the most common Candida species isolated from HIV-infected children, followed by C. dubliniensis, C. glabrata, and C. tropicalis. In the HIV-positive group, the prevalence of Candida isolation was significantly higher in children who presented with low CD4+-T-lymphocyte counts, elevated viral loads, and gingivitis. PMID:15583343

  14. Multifunctionality and diversity in bacterial biofilms

    National Research Council Canada - National Science Library

    Peter, Hannes; Ylla, Irene; Gudasz, Cristian; Romaní, Anna M; Sabater, Sergi; Tranvik, Lars J

    2011-01-01

    .... In freshwater ecosystems, biofilms are metabolic hotspots and major sites of DOC degradation. We manipulated the diversity of biofilm forming communities which were fed with DOC differing in availability...

  15. Candida Biofilms: Development, Architecture, and Resistance

    Science.gov (United States)

    CHANDRA, JYOTSNA; MUKHERJEE, PRANAB K.

    2015-01-01

    Intravascular device–related infections are often associated with biofilms (microbial communities encased within a polysaccharide-rich extracellular matrix) formed by pathogens on the surfaces of these devices. Candida species are the most common fungi isolated from catheter-, denture-, and voice prosthesis–associated infections and also are commonly isolated from contact lens–related infections (e.g., fungal keratitis). These biofilms exhibit decreased susceptibility to most antimicrobial agents, which contributes to the persistence of infection. Recent technological advances have facilitated the development of novel approaches to investigate the formation of biofilms and identify specific markers for biofilms. These studies have provided extensive knowledge of the effect of different variables, including growth time, nutrients, and physiological conditions, on biofilm formation, morphology, and architecture. In this article, we will focus on fungal biofilms (mainly Candida biofilms) and provide an update on the development, architecture, and resistance mechanisms of biofilms. PMID:26350306

  16. Ciliates as engineers of phototrophic biofilms

    NARCIS (Netherlands)

    Weerman, Ellen J.; van der Geest, Harm G.; van der Meulen, Myra D.; Manders, Erik M. M.; van de Koppel, Johan; Herman, Peter M. J.; Admiraal, Wim

    1. Phototrophic biofilms consist of a matrix of phototrophs, non-photosynthetic bacteria and extracellular polymeric substances (EPS) which is spatially structured. Despite widespread exploitation of algae and bacteria within phototrophic biofilms, for example by protozoans, the 'engineering'

  17. Killing of Serratia marcescens biofilms with chloramphenicol.

    Science.gov (United States)

    Ray, Christopher; Shenoy, Anukul T; Orihuela, Carlos J; González-Juarbe, Norberto

    2017-03-29

    Serratia marcescens is a Gram-negative bacterium with proven resistance to multiple antibiotics and causative of catheter-associated infections. Bacterial colonization of catheters mainly involves the formation of biofilm. The objectives of this study were to explore the susceptibility of S. marcescens biofilms to high doses of common antibiotics and non-antimicrobial agents. Biofilms formed by a clinical isolate of S. marcescens were treated with ceftriaxone, kanamycin, gentamicin, and chloramphenicol at doses corresponding to 10, 100 and 1000 times their planktonic minimum inhibitory concentration. In addition, biofilms were also treated with chemical compounds such as polysorbate-80 and ursolic acid. S. marcescens demonstrated susceptibility to ceftriaxone, kanamycin, gentamicin, and chloramphenicol in its planktonic form, however, only chloramphenicol reduced both biofilm biomass and biofilm viability. Polysorbate-80 and ursolic acid had minimal to no effect on either planktonic and biofilm grown S. marcescens. Our results suggest that supratherapeutic doses of chloramphenicol can be used effectively against established S. marcescens biofilms.

  18. Role of sediment size and biostratinomy on the development of biofilms in recent avian vertebrate remains

    Science.gov (United States)

    Peterson, Joseph E.; Lenczewski, Melissa E.; Clawson, Steven R.; Warnock, Jonathan P.

    2017-04-01

    Microscopic soft tissues have been identified in fossil vertebrate remains collected from various lithologies. However, the diagenetic mechanisms to preserve such tissues have remained elusive. While previous studies have described infiltration of biofilms in Haversian and Volkmann’s canals, biostratinomic alteration (e.g., trampling), and iron derived from hemoglobin as playing roles in the preservation processes, the influence of sediment texture has not previously been investigated. This study uses a Kolmogorov Smirnov Goodness-of-Fit test to explore the influence of biostratinomic variability and burial media against the infiltration of biofilms in bone samples. Controlled columns of sediment with bone samples were used to simulate burial and subsequent groundwater flow. Sediments used in this study include clay-, silt-, and sand-sized particles modeled after various fluvial facies commonly associated with fossil vertebrates. Extant limb bone samples obtained from Gallus gallus domesticus (Domestic Chicken) buried in clay-rich sediment exhibit heavy biofilm infiltration, while bones buried in sands and silts exhibit moderate levels. Crushed bones exhibit significantly lower biofilm infiltration than whole bone samples. Strong interactions between biostratinomic alteration and sediment size are also identified with respect to biofilm development. Sediments modeling crevasse splay deposits exhibit considerable variability; whole-bone crevasse splay samples exhibit higher frequencies of high-level biofilm infiltration, and crushed-bone samples in modeled crevasse splay deposits display relatively high frequencies of low-level biofilm infiltration. These results suggest that sediment size, depositional setting, and biostratinomic condition play key roles in biofilm infiltration in vertebrate remains, and may influence soft tissue preservation in fossil vertebrates.

  19. Biofilm detection in natural unconsolidated porous media using a low-field magnetic resonance system.

    Science.gov (United States)

    Sanderlin, Alexis B; Vogt, Sarah J; Grunewald, Elliot; Bergin, Bridget A; Codd, Sarah L

    2013-01-15

    The extent to which T(2) relaxation measurements can be used to determine biofouling in several natural geological sand media using a low-field (275 kHz, 6.5 mT) NMR system has been demonstrated. It has been previously shown that, at high laboratory strength fields (300 MHz, 7 T), T(2) techniques can be used as a bioassay to confirm the growth of biofilm inside opaque porous media with low magnetic susceptibilities such as borosilicate or soda lime glass beads. Additionally decreases in T(2) can be associated with intact biofilm as opposed to degraded biofilm material. However, in natural geological media, the strong susceptibility gradients generated at high fields dominated the T(2) relaxation time distributions and biofilm growth could not be reliably detected. Samples studied included Bacillus mojavensis biofilm in several sand types, as well as alginate solution and alginate gel in several sand types. One of the sand types was highly magnetic. Data was collected with a low-field (275 kHz, 6.5 mT) benchtop NMR system using a CPMG sequence with an echo time of 1.25 ms providing the ability to detect signals with T(2) greater than 1 ms. Data presented here clearly demonstrate that biofilm can be reliably detected and monitored in highly magnetically susceptible geological samples using a low-field NMR spectrometer indicating that low-field NMR could be viable as a biofilm sensor at bioremedation sites.

  20. Effect of Twice-Daily Blue Light Treatment on Matrix-Rich Biofilm Development.

    Directory of Open Access Journals (Sweden)

    Denise Lins de Sousa

    Full Text Available The use of blue light has been proposed as a direct means of affecting local bacterial infections, however the use of blue light without a photosensitizer to prevent the biofilm development has not yet been explored. The aim of this study was to determine how the twice-daily treatment with blue light affects the development and composition of a matrix-rich biofilm.Biofilms of Streptococcus mutans UA159 were formed on saliva-coated hydroxyapatite discs for 5 days. The biofilms were exposed twice-daily to non-coherent blue light (LumaCare; 420 nm without a photosensitizer. The distance between the light and the sample was 1.0 cm; energy density of 72 J cm-2; and exposure time of 12 min 56 s. Positive and negative controls were twice-daily 0.12% chlorhexidine (CHX and 0.89% NaCl, respectively. Biofilms were analyzed for bacterial viability, dry-weight, and extra (EPS-insoluble and soluble and intracellular (IPS polysaccharides. Variable pressure scanning electron microscopy and confocal scanning laser microscopy were used to check biofilm morphology and bacterial viability, respectively. When biofilms were exposed to twice-daily blue light, EPS-insoluble was reduced significantly more than in either control group (CHX and 0.89% NaCl. Bacterial viability and dry weight were also reduced relative to the negative control (0.89% NaCl when the biofilms were treated with twice-daily blue light. Different morphology was also visible when the biofilms were treated with blue light.Twice-daily treatment with blue light without a photosensitizer is a promising mechanism for the inhibition of matrix-rich biofilm development.

  1. Effect of Twice-Daily Blue Light Treatment on Matrix-Rich Biofilm Development.

    Science.gov (United States)

    de Sousa, Denise Lins; Lima, Ramille Araújo; Zanin, Iriana Carla; Klein, Marlise I; Janal, Malvin N; Duarte, Simone

    2015-01-01

    The use of blue light has been proposed as a direct means of affecting local bacterial infections, however the use of blue light without a photosensitizer to prevent the biofilm development has not yet been explored. The aim of this study was to determine how the twice-daily treatment with blue light affects the development and composition of a matrix-rich biofilm. Biofilms of Streptococcus mutans UA159 were formed on saliva-coated hydroxyapatite discs for 5 days. The biofilms were exposed twice-daily to non-coherent blue light (LumaCare; 420 nm) without a photosensitizer. The distance between the light and the sample was 1.0 cm; energy density of 72 J cm-2; and exposure time of 12 min 56 s. Positive and negative controls were twice-daily 0.12% chlorhexidine (CHX) and 0.89% NaCl, respectively. Biofilms were analyzed for bacterial viability, dry-weight, and extra (EPS-insoluble and soluble) and intracellular (IPS) polysaccharides. Variable pressure scanning electron microscopy and confocal scanning laser microscopy were used to check biofilm morphology and bacterial viability, respectively. When biofilms were exposed to twice-daily blue light, EPS-insoluble was reduced significantly more than in either control group (CHX and 0.89% NaCl). Bacterial viability and dry weight were also reduced relative to the negative control (0.89% NaCl) when the biofilms were treated with twice-daily blue light. Different morphology was also visible when the biofilms were treated with blue light. Twice-daily treatment with blue light without a photosensitizer is a promising mechanism for the inhibition of matrix-rich biofilm development.

  2. Metabolic activity of Streptococcus mutans biofilms and gene expression during exposure to xylitol and sucrose.

    Science.gov (United States)

    Decker, Eva-Maria; Klein, Christian; Schwindt, Dimitri; von Ohle, Christiane

    2014-12-01

    The objective of the study was to analyse Streptococcus mutans biofilms grown under different dietary conditions by using multifaceted methodological approaches to gain deeper insight into the cariogenic impact of carbohydrates. S. mutans biofilms were generated during a period of 24 h in the following media: Schaedler broth as a control medium containing endogenous glucose, Schaedler broth with an additional 5% sucrose, and Schaedler broth supplemented with 1% xylitol. The confocal laser scanning microscopy (CLSM)-based analyses of the microbial vitality, respiratory activity (5-cyano-2,3-ditolyl tetrazolium chloride, CTC) and production of extracellular polysaccharides (EPS) were performed separately in the inner, middle and outer biofilm layers. In addition to the microbiological sample testing, the glucose/sucrose consumption of the biofilm bacteria was quantified, and the expression of glucosyltransferases and other biofilm-associated genes was investigated. Xylitol exposure did not inhibit the viability of S. mutans biofilms, as monitored by the following experimental parameters: culture growth, vitality, CTC activity and EPS production. However, xylitol exposure caused a difference in gene expression compared to the control. GtfC was upregulated only in the presence of xylitol. Under xylitol exposure, gtfB was upregulated by a factor of 6, while under sucrose exposure, it was upregulated by a factor of three. Compared with glucose and xylitol, sucrose increased cell vitality in all biofilm layers. In all nutrient media, the intrinsic glucose was almost completely consumed by the cells of the S. mutans biofilm within 24 h. After 24 h of biofilm formation, the multiparametric measurements showed that xylitol in the presence of glucose caused predominantly genotypic differences but did not induce metabolic differences compared to the control. Thus, the availability of dietary carbohydrates in either a pure or combined form seems to affect the

  3. Human pathogenic viruses are retained in and released by Candida albicans biofilm in vitro.

    Science.gov (United States)

    Mazaheritehrani, Elham; Sala, Arianna; Orsi, Carlotta Francesca; Neglia, Rachele Giovanna; Morace, Giulia; Blasi, Elisabetta; Cermelli, Claudio

    2014-01-22

    Candida albicans is the most prevalent human fungal pathogen associated with biofilm formation on indwelling medical devices. Under this form, Candida represents an infectious reservoir difficult to eradicate and possibly responsible for systemic, often lethal infections. Currently, no information is available on the occurrence and persistence of pathogenic viruses within C. albicans biofilm. Therefore, the aim of this study was to investigate whether Herpes Simplex Virus type 1 (HSV-1) and Coxsackievirus type B5 (CVB5) can be encompassed in Candida biofilm, retain their infectivity and then be released. Thus, cell-free virus inocula or HSV-1-infected cells were added to 24h-old fungal biofilm in tissue culture plates; 48 h later, the biofilm was detached by washing and energetic scratching and the presence of virus in the rescued material was end-point titrated on VERO cells. Planktonic Candida cultures and samples containing only medium were run in parallel as controls. We found that both HSV-1 and CVB5 free virus particles, as well as HSV-1 infected cells remain embedded in the biofilm retaining their infectivity. As a second step, the influence of biofilm on virus sensitivity to sodium hypochlorite and to specific neutralizing antibodies was investigated. The results showed that virus encompassment in fungal biofilm reduces virus sensitivity to chemical inactivation but does not affect antibody neutralization. Overall, these data provide the first in vitro evidence that viruses can be encompassed within Candida biofilm and then be released. Thus, it may be speculated that Candida biofilm can be a reservoir of viruses too, posing a further health risk. Copyright © 2013 Elsevier B.V. All rights reserved.

  4. Staphylococcus epidermidis and biofilm-associated neutrophils in chronic rhinosinusitis. A pilot study.

    Science.gov (United States)

    Marcinkiewicz, Janusz; Stręk, Paweł; Strus, Magdalena; Głowacki, Roman; Ciszek-Lenda, Marta; Zagórska-Świeży, Katarzyna; Gawda, Anna; Tomusiak, Anna

    2015-12-01

    A key role of bacterial biofilm in the pathogenesis of chronic rhinosinusitis (CRS) with (CRSwNP) and without nasal polyps (CRSsNP) is commonly accepted. However, the impact of some bacterial species isolated from inflamed sinus mucosa on biofilm formation is unclear. In particular, the role of Staphylococcus epidermidis as aetiological agents of CRS is controversial. Moreover, the effect of biofilm formation on neutrophil infiltration and activity in CRSwNP calls for explanation. In this study, biofilms were found in three of 10 patients (mean age = 46 ± 14) with CRS undergoing endoscopic sinus surgery by means of scanning electron microscopy. Unexpectedly, S. epidermidis was the primary isolated bacteria and was also found to be present in all biofilm-positive mucosa specimens, indicating its pivotal role in the pathogenesis of severe chronic infections associated with biofilm formation. We have also measured the activity of myeloperoxidase (MPO), the most abundant neutrophil enzyme, to demonstrate the presence of neutrophils in the samples tested. Our present results show that the level of MPO in CRS associated with biofilm is lower than that without biofilm. It may suggest either a low number of neutrophils or the presence of a type of neutrophils with compromised antimicrobial activity, described as biofilm-associated neutrophils (BAN). Finally, we conclude that further studies with a large number of CRS cases should be performed to establish the association between S. epidermidis and other frequently isolated bacterial species from paranasal sinuses, with the severity of CRS, biofilm formation and the infiltration of BAN. © 2016 The Authors. International Journal of Experimental Pathology © 2016 International Journal of Experimental Pathology.

  5. Small molecule control of bacterial biofilms

    OpenAIRE

    Worthington, Roberta J.; Richards, Justin J.; Melander, Christian

    2012-01-01

    Bacterial biofilms are defined as a surface attached community of bacteria embedded in a matrix of extracellular polymeric substances that they have produced. When in the biofilm state, bacteria are more resistant to antibiotics and the host immune response than are their planktonic counterparts. Biofilms are increasingly recognized as being significant in human disease, accounting for 80% of bacterial infections in the body and diseases associated with bacterial biofilms include: lung infect...

  6. Cleaning and Disinfection of Bacillus cereus Biofilm.

    Science.gov (United States)

    Deal, Amanda; Klein, Dan; Lopolito, Paul; Schwarz, John Spencer

    2016-01-01

    Methodology has been evolving for the testing of disinfectants against bacterial single-species biofilms, as the difficulty of biofilm remediation continues to gain much-needed attention. Bacterial single-species biofilm contamination presents a real risk to good manufacturing practice-regulated industries. However, mixed-species biofilms and biofilms containing bacterial spores remain an even greater challenge for cleaning and disinfection. Among spore-forming microorganisms frequently encountered in pharmaceutical manufacturing areas, the spores of Bacillus cereus are often determined to be the hardest to disinfect and eradicate. One of the reasons for the low degree of susceptibility to disinfection is the ability of these spores to be encapsulated within an exopolysachharide biofilm matrix. In this series of experiments, we evaluated the disinfectant susceptibility of B. cereus biofilms relative to disassociated B. cereus spores and biofilm from a non-spore-forming species. Further, we assessed the impact that pre-cleaning has on increasing that susceptibility. Methodology has been evolving for the testing of disinfectants against bacterial single-species biofilms, as the difficulty of biofilm remediation continues to gain much-needed attention. Bacterial single-species biofilm contamination presents a real risk to good manufacturing practice-regulated industries. However, mixed-species biofilms and biofilms containing bacterial spores remain an even greater challenge for cleaning and disinfection. Among spore-forming microorganisms frequently encountered in pharmaceutical manufacturing areas, the spores of Bacillus cereus are often determined to be the hardest to disinfect and eradicate. One of the reasons for the low degree of susceptibility to disinfection is the ability of these spores to be encapsulated within an exopolysachharide biofilm matrix. In this series of experiments, we evaluated the disinfectant susceptibility of B. cereus biofilms relative to

  7. Novel method for quantitative estimation of biofilms

    DEFF Research Database (Denmark)

    Syal, Kirtimaan

    2017-01-01

    were quantified by the proposed protocol. For ease in referring, this method has been described as the Syal method for biofilm quantification. This new method was found to be useful for the estimation of early phase biofilm and aerobic biofilm layer formed at the liquid-air interphase. The biofilms...... formed by all three tested bacteria-B. subtilis, E. coli and M. smegmatis, were precisely quantified....

  8. High bacterial diversity in epilithic biofilms of oligotrophic mountain lakes.

    Science.gov (United States)

    Bartrons, Mireia; Catalan, Jordi; Casamayor, Emilio O

    2012-11-01

    Benthic microbial biofilms attached to rocks (epilithic) are major sites of carbon cycling and can dominate ecosystem primary production in oligotrophic lakes. We studied the bacterial community composition of littoral epilithic biofilms in five connected oligotrophic high mountain lakes located at different altitudes by genetic fingerprinting and clone libraries of the 16S rRNA gene. Different intra-lake samples were analyzed, and consistent changes in community structure (chlorophyll a and organic matter contents, and bacterial community composition) were observed along the altitudinal gradient, particularly related with the location of the lake above or below the treeline. Epilithic biofilm genetic fingerprints were both more diverse among lakes than within lakes and significantly different between montane (below the tree line) and alpine lakes (above the tree line). The genetic richness in the epilithic biofilm was much higher than in the plankton of the same lacustrine area studied in previous works, with significantly idiosyncratic phylogenetic composition (specifically distinct from lake plankton or mountain soils). Data suggest the coexistence of aerobic, anaerobic, phototrophic, and chemotrophic microorganisms in the biofilm, Bacteroidetes and Cyanobacteria being the most important bacterial taxa, followed by Alpha-, Beta-, Gamma-, and Deltaproteobacteria, Chlorobi, Planctomycetes, and Verrucomicrobia. The degree of novelty was especially high for epilithic Bacteroidetes, and up to 50 % of the sequences formed monophyletic clusters distantly related to any previously reported sequence. More than 35 % of the total sequences matched at <95 % identity to any previously reported 16S rRNA gene, indicating that alpine epilithic biofilms are unexplored habitats that contain a substantial degree of novelty within a short geographical distance. Further research is needed to determine whether these communities are involved in more biogeochemical pathways than

  9. First evidence of sternal wound biofilm following cardiac surgery.

    Directory of Open Access Journals (Sweden)

    Haytham Elgharably

    Full Text Available Management of deep sternal wound infection (SWI, a serious complication after cardiac surgery with high morbidity and mortality incidence, requires invasive procedures such as, debridement with primary closure or myocutaneous flap reconstruction along with use of broad spectrum antibiotics. The purpose of this clinical series is to investigate the presence of biofilm in patients with deep SWI. A biofilm is a complex microbial community in which bacteria attach to a biological or non-biological surface and are embedded in a self-produced extracellular polymeric substance. Biofilm related infections represent a major clinical challenge due to their resistance to both host immune defenses and standard antimicrobial therapies. Candidates for this clinical series were patients scheduled for a debridement procedure of an infected sternal wound after a cardiac surgery. Six patients with SWI were recruited in the study. All cases had marked dehiscence of all layers of the wound down to the sternum with no signs of healing after receiving broad spectrum antibiotics post-surgery. After consenting patients, tissue and/or extracted stainless steel wires were collected during the debridement procedure. Debrided tissues examined by Gram stain showed large aggregations of Gram positive cocci. Immuno-fluorescent staining of the debrided tissues using a specific antibody against staphylococci demonstrated the presence of thick clumps of staphylococci colonizing the wound bed. Evaluation of tissue samples with scanning electron microscope (SEM imaging showed three-dimensional aggregates of these cocci attached to the wound surface. More interestingly, SEM imaging of the extracted wires showed attachment of cocci aggregations to the wire metal surface. These observations along with the clinical presentation of the patients provide the first evidence that supports the presence of biofilm in such cases. Clinical introduction of the biofilm infection concept in deep

  10. Antimicrobial Photoinactivation Using Visible Light Plus Water-Filtered Infrared-A (VIS + wIRA Alters In Situ Oral Biofilms.

    Directory of Open Access Journals (Sweden)

    A Al-Ahmad

    Full Text Available Recently, growing attention has been paid to antimicrobial photodynamic therapy (aPDT in dentistry. Changing the microbial composition of initial and mature oral biofilm by aPDT using visible light plus water-filtered infrared-A wavelengths (VIS + wIRA has not yet been investigated. Moreover, most aPDT studies have been conducted on planktonic bacterial cultures. Therefore, in the present clinical study we cultivated initial and mature oral biofilms in six healthy volunteers for 2 hours or 3 days, respectively. The biofilms were treated with aPDT using VIS+wIRA (200 mW cm(-2, toluidine blue (TB and chlorine e6 (Ce6 for 5 minutes. Chlorhexidine treated biofilm samples served as positive controls, while untreated biofilms served as negative controls. After aPDT treatment the colony forming units (CFU of the biofilm samples were quantified, and the surviving bacteria were isolated in pure cultures and identified using MALDI-TOF, biochemical tests and 16S rDNA-sequencing. aPDT killed more than 99.9% of the initial viable bacterial count and 95% of the mature oral biofilm in situ, independent of the photosensitizer. The number of surviving bacterial species was highly reduced to 6 (TB and 4 (Ce6 in the treated initial oral biofilm compared to the 20 different species of the untreated biofilm. The proportions of surviving bacterial species were also changed after TB- and Ce6-mediated aPDT of the mature oral biofilm, resulting in a shift in the microbial composition of the treated biofilm compared to that of the control biofilm. In conclusion, aPDT using VIS + wIRA showed a remarkable potential to eradicate both initial and mature oral biofilms, and also to markedly alter the remaining biofilm. This encourages the clinical use of aPDT with VIS + wIRA for the treatment of periimplantitis and periodontitis.

  11. Antimicrobial Photoinactivation Using Visible Light Plus Water-Filtered Infrared-A (VIS + wIRA) Alters In Situ Oral Biofilms

    Science.gov (United States)

    Al-Ahmad, A.; Bucher, M.; Anderson, A. C.; Tennert, C.; Hellwig, E.; Wittmer, A.; Vach, K.; Karygianni, L.

    2015-01-01

    Recently, growing attention has been paid to antimicrobial photodynamic therapy (aPDT) in dentistry. Changing the microbial composition of initial and mature oral biofilm by aPDT using visible light plus water-filtered infrared-A wavelengths (VIS + wIRA) has not yet been investigated. Moreover, most aPDT studies have been conducted on planktonic bacterial cultures. Therefore, in the present clinical study we cultivated initial and mature oral biofilms in six healthy volunteers for 2 hours or 3 days, respectively. The biofilms were treated with aPDT using VIS+wIRA (200 mW cm-2), toluidine blue (TB) and chlorine e6 (Ce6) for 5 minutes. Chlorhexidine treated biofilm samples served as positive controls, while untreated biofilms served as negative controls. After aPDT treatment the colony forming units (CFU) of the biofilm samples were quantified, and the surviving bacteria were isolated in pure cultures and identified using MALDI-TOF, biochemical tests and 16S rDNA-sequencing. aPDT killed more than 99.9% of the initial viable bacterial count and 95% of the mature oral biofilm in situ, independent of the photosensitizer. The number of surviving bacterial species was highly reduced to 6 (TB) and 4 (Ce6) in the treated initial oral biofilm compared to the 20 different species of the untreated biofilm. The proportions of surviving bacterial species were also changed after TB- and Ce6-mediated aPDT of the mature oral biofilm, resulting in a shift in the microbial composition of the treated biofilm compared to that of the control biofilm. In conclusion, aPDT using VIS + wIRA showed a remarkable potential to eradicate both initial and mature oral biofilms, and also to markedly alter the remaining biofilm. This encourages the clinical use of aPDT with VIS + wIRA for the treatment of periimplantitis and periodontitis. PMID:26162100

  12. Antibiotic penetration and bacterial killing in a Pseudomonas aeruginosa biofilm model

    DEFF Research Database (Denmark)

    Cao, Bao; Christophersen, Lars; Thomsen, Kim

    2015-01-01

    OBJECTIVES: Treating biofilm infections successfully is a challenge. We hypothesized that biofilms may be considered as independent compartments with particular pharmacokinetics. We therefore studied the pharmacokinetics and pharmacodynamics of tobramycin in a seaweed alginate-embedded biofilm...... model. METHODS: Seaweed alginate beads containing Pseudomonas aeruginosa were cultured in LB medium, sampled at day 1, 3, 5 or 7 and examined for the effect of treatment with tobramycin for 30 min. Treated beads were homogenized and the number of cfu was determined. The antibiotic concentration...

  13. Confocal microscopy imaging of the biofilm matrix

    DEFF Research Database (Denmark)

    Schlafer, Sebastian; Meyer, Rikke L

    2017-01-01

    The extracellular matrix is an integral part of microbial biofilms and an important field of research. Confocal laser scanning microscopy is a valuable tool for the study of biofilms, and in particular of the biofilm matrix, as it allows real-time visualization of fully hydrated, living specimens...

  14. Microbiële biofilms in tandheelkunde

    NARCIS (Netherlands)

    Krom, B.P.

    2015-01-01

    Aangehechte gemeenschappen van micro-organismen, ook wel biofilms genoemd, zijn altijd en overal aanwezig. Hoewel biofilms een slechte naam hebben, zijn ze meestal natuurlijk, gezond en zelfs gewenst. In de tandartspraktijk komen zowel gezonde (orale biofilms) als ongezonde (bijv. in de waterleiding

  15. Microbiële biofilms in tandheelkunde

    NARCIS (Netherlands)

    Krom, B.P.

    2015-01-01

    Aangehechte gemeenschappen van micro-organismen, ook wel biofilms genoemd, zijn altijd en overal aanwezig. Hoewel biofilms een slechte naam hebben, zijn ze meestal natuurlijk, gezond en zelfs gewenst. In de mondzorgpraktijk komen zowel gezonde (orale biofilms) als ongezonde (bijv. in de waterleiding

  16. Extracellular DNA Contributes to Dental Biofilm Stability.

    Science.gov (United States)

    Schlafer, Sebastian; Meyer, Rikke L; Dige, Irene; Regina, Viduthalai R

    2017-01-01

    Extracellular DNA (eDNA) is a major matrix component of many bacterial biofilms. While the presence of eDNA and its role in biofilm stability have been demonstrated for several laboratory biofilms of oral bacteria, there is no data available on the presence and function of eDNA in in vivo grown dental biofilms. This study aimed to determine whether eDNA was part of the matrix in biofilms grown in situ in the absence of sucrose and whether treatment with DNase dispersed biofilms grown for 2.5, 5, 7.5, 16.5, or 24 h. Three hundred biofilms from 10 study participants were collected and treated with either DNase or heat-inactivated DNase for 1 h. The bacterial biovolume was determined with digital image analysis. Staining with TOTO®-1 allowed visualization of eDNA both on bacterial cell surfaces and, with a cloud-like appearance, in the intercellular space. DNase treatment strongly reduced the amount of biofilm in very early stages of growth (up to 7.5 h), but the treatment effect decreased with increasing biofilm age. This study proves the involvement of eDNA in dental biofilm formation and its importance for biofilm stability in the earliest stages. Further research is required to uncover the interplay of eDNA and other matrix components and to explore the therapeutic potential of DNase treatment for biofilm control. © 2017 S. Karger AG, Basel.

  17. Strategies for combating bacterial biofilm infections

    DEFF Research Database (Denmark)

    Wu, Hong; Moser, Claus Ernst; Wang, Heng-Zhuang

    2015-01-01

    Formation of biofilm is a survival strategy for bacteria and fungi to adapt to their living environment, especially in the hostile environment. Under the protection of biofilm, microbial cells in biofilm become tolerant and resistant to antibiotics and the immune responses, which increases...

  18. Habits of Highly Effective Biofilms: Ion Signaling.

    Science.gov (United States)

    Libby, Elizabeth A; Dworkin, Jonathan

    2017-06-15

    How do neighboring bacterial biofilms sense and communicate with each other? In a recent paper, Liu et al. (2017) demonstrate how electrical signaling allows communication of metabolic states between adjacent B. subtilis biofilms, providing a possible generalizable mechanism for communication in multispecies biofilms with interdependent metabolism. Copyright © 2017 Elsevier Inc. All rights reserved.

  19. Colonization of peripheral intravascular catheters with biofilm ...

    African Journals Online (AJOL)

    Background: Biofilms often colonize catheters and contribute to catheter-related septicemia. However, predictors of catheter colonization by biofilms remain poorly defined. The aim of this study was to evaluate clinical factors that may be associated with biofilm colonization of catheters. Materials and Methods: A total of 54 ...

  20. Microbial Biofilm and Bacterial Contamination on Pig Carcasses

    Directory of Open Access Journals (Sweden)

    Adriana Morar

    2010-10-01

    Full Text Available The aim of this study was to emphasize the presence of biofilm on meat surfaces using epifluorescences microscopy and establishing the microbial contamination level by classical microbiological methods. The research was performed in a pork slaughterhouse. The presence of microbial biofilm and the level of contamination were performed on surfaces from pig carcasses and cut pieces. Clusters of microorganisms included in a biofilm matrix were found on the surface of carcasses on sternal region, coast region, coccigian region and on surfaces of cut pieces: chop, front of thighs. Microbial biofilm was present on carcasses and cut pieces at least 3 days length, in regions with high humidity and microbial contamination level ranged of 102- 103 cfu/ cm2. The microbial load of the surfaces was assessed using the following microbiological indicators: total viable count (TVC, the number of enterobacteria and Pseudomonas genus. The level of carcasses contamination ranged on average from 1.3 x 10 cfu/ cm2 (neck to 2.6 x 103 cfu/cm2 (front of pulp. The proportion of Enterobacteriaceae-positive samples was 60%, with a low level of contamination (less than 1 cfu/ cm2. Germs of the Pseudomonas genus were absent in all the analyzed samples.

  1. Evaluation of environmental scanning electron microscopy for analysis of Proteus mirabilis crystalline biofilms in situ on urinary catheters.

    Science.gov (United States)

    Holling, Nina; Dedi, Cinzia; Jones, Caroline E; Hawthorne, Joseph A; Hanlon, Geoffrey W; Salvage, Jonathan P; Patel, Bhavik A; Barnes, Lara M; Jones, Brian V

    2014-06-01

    Proteus mirabilis is a common cause of catheter-associated urinary tract infections and frequently leads to blockage of catheters due to crystalline biofilm formation. Scanning electron microscopy (SEM) has proven to be a valuable tool in the study of these unusual biofilms, but entails laborious sample preparation that can introduce artefacts, undermining the investigation of biofilm development. In contrast, environmental scanning electron microscopy (ESEM) permits imaging of unprocessed, fully hydrated samples, which may provide much insight into the development of P. mirabilis biofilms. Here, we evaluate the utility of ESEM for the study of P. mirabilis crystalline biofilms in situ, on urinary catheters. In doing so, we compare this to commonly used conventional SEM approaches for sample preparation and imaging. Overall, ESEM provided excellent resolution of biofilms formed on urinary catheters and revealed structures not observed in standard SEM imaging or previously described in other studies of these biofilms. In addition, we show that energy-dispersive X-ray spectroscopy (EDS) may be employed in conjunction with ESEM to provide information regarding the elemental composition of crystalline structures and demonstrate the potential for ESEM in combination with EDS to constitute a useful tool in exploring the mechanisms underpinning crystalline biofilm formation. © 2014 The Authors. FEMS Microbiology Letters published by John Wiley & Sons Ltd on behalf of Federation of European Microbiological Societies.

  2. A Pyrosequencing Investigation of Differences in the Feline Subgingival Microbiota in Health, Gingivitis and Mild Periodontitis

    Science.gov (United States)

    Harris, Stephen; Croft, Julie; O’Flynn, Ciaran; Deusch, Oliver; Colyer, Alison; Allsopp, Judi; Milella, Lisa; Davis, Ian J.

    2015-01-01

    Periodontitis is the most frequently diagnosed health problem in cats yet little is known about the bacterial species important for the disease. The objective of this study was to identify bacterial species associated with health, gingivitis or mild periodontitis (periodontitis. Pyrosequencing of the V1-V3 region of the 16S rDNA from these plaque samples generated more than one million reads and identified a total of 267 operational taxonomic units after bioinformatic and statistical analysis. Porphyromonas was the most abundant genus in all gingival health categories, particularly in health along with Moraxella and Fusobacteria. The Peptostreptococcaceae were the most abundant family in gingivitis and mild periodontitis. Logistic regression analysis identified species from various genera that were significantly associated with health, gingivitis or mild periodontitis. The species identified were very similar to those observed in canine plaque in the corresponding health and disease states. Such similarities were not observed between cat and human at the bacterial species level but with disease progression similarities did emerge at the phylum level. This suggests that interventions targeted at human pathogenic species will not be effective for use in cats but there is more potential for commonalities in interventions for cats and dogs. PMID:26605793

  3. A Pyrosequencing Investigation of Differences in the Feline Subgingival Microbiota in Health, Gingivitis and Mild Periodontitis.

    Science.gov (United States)

    Harris, Stephen; Croft, Julie; O'Flynn, Ciaran; Deusch, Oliver; Colyer, Alison; Allsopp, Judi; Milella, Lisa; Davis, Ian J

    2015-01-01

    Periodontitis is the most frequently diagnosed health problem in cats yet little is known about the bacterial species important for the disease. The objective of this study was to identify bacterial species associated with health, gingivitis or mild periodontitis (gingivitis or mild periodontitis. Pyrosequencing of the V1-V3 region of the 16S rDNA from these plaque samples generated more than one million reads and identified a total of 267 operational taxonomic units after bioinformatic and statistical analysis. Porphyromonas was the most abundant genus in all gingival health categories, particularly in health along with Moraxella and Fusobacteria. The Peptostreptococcaceae were the most abundant family in gingivitis and mild periodontitis. Logistic regression analysis identified species from various genera that were significantly associated with health, gingivitis or mild periodontitis. The species identified were very similar to those observed in canine plaque in the corresponding health and disease states. Such similarities were not observed between cat and human at the bacterial species level but with disease progression similarities did emerge at the phylum level. This suggests that interventions targeted at human pathogenic species will not be effective for use in cats but there is more potential for commonalities in interventions for cats and dogs.

  4. Application of metabolomics to understanding biofilms in water distribution systems: a pilot study.

    Science.gov (United States)

    Beale, D J; Barratt, R; Marlow, D R; Dunn, M S; Palombo, E A; Morrison, P D; Key, C

    2013-01-01

    Biofilms formed in pipes are known to contribute to waterborne diseases, accelerate corrosion and cause aesthetic taste and odour issues within the potable water supply network. This paper describes a pilot study, undertaken to assess the potential of using metabolomics to monitor bacterial activity in biofilms of an urban water network. Using samples from a water mains flushing programme, it was found that a profile of intracellular and extracellular metabolites associated with microbial activity could be obtained by analysing samples using gas chromatography mass spectrometry. Chemometric analysis of the chromatograms in conjunction with data from the mass spectrometer showed that it is possible to differentiate between biofilms from different pipe materials and planktonic bacteria. This research demonstrates that metabolomics has the potential for investigating biofilms and other microbial activity within water networks, and could provide a means for enhancing monitoring programmes, understanding the source of water quality complaints, and optimising water network management strategies.

  5. Prevalence of actinobacillus actinomycetemcomitans and prophyromonas gingivalis in subgingival microflora of patients with aggressive periodontitis

    Directory of Open Access Journals (Sweden)

    Paknejad M.

    2005-05-01

    Full Text Available Statement of Problem: One of the best ways for treatment of Aggressive Periodontitis (AP is identification and elimination of etiologic factors specially two microorganisms Actinobacillus actinomycetemcomitans (Aa and Porphyromonas gingivalis (Pg in patients harboring them. Purpose: This study determines the prevalence of Aa and Pg and its correlation with age, sex and the number of family members as well as probing pocket depth (PPD in active sites of AP patients, referred to department of periodontics, Faculty of Dentistry, Tehran University of Medical Sciences. Materials and Methods: In this cross sectional, descriptive study, 54 sites (PPD> 5mm in 15 patients were considered for culture. Marginal gingiva was dried and sampling performed by paperpoint (#30. The selective medium for Aa, was Trypticase Soy Agar-Bacitracin- Vancomycin (TSBV and for Pg was Brucella agar. Results were analyzed using Fisher and Chi-Square statistical tests. Results: Thirteen patients or 38 sites (70.4% were identified as Aa positive and 3 patients or 10 sites (18.4% were Pg positive. There was no significant relation between the presence of Aa and sex or age (P=0.086. Pg was more prevalent in men compared with women (P<0.0001 but with regard to age there was no statistical difference between men and women. Aa had a significant positive correlation with PPD (P=0.002, which was not true for Pg. In addition, the number of positive sites showed a significant negative correlation with the number of family members. Conclusion: Based on the present study, the prevalence of Aa in deep pockets in patients with AP is higher than Pg.

  6. Microbial pathogenesis and biofilm development

    DEFF Research Database (Denmark)

    Reisner, A.; Høiby, N.; Tolker-Nielsen, Tim

    2004-01-01

    cycles of different microorganisms will eventually lead to improved treatments. Several bacteria have evolved specific strategies for virulent colonization of humans in addition to their otherwise harmless establishment as environmental inhabitants. In many such cases biofilm development seems to play...... permit bacterial growth to occur. In laboratory model systems the growth of the surface-associated bacteria is supported by the nutrient supply in the moving or standing liquid. A benchmark of biofilm formation by several organisms in vitro is the development of three-dimensional structures that have...... been termed 'maturation', which is thought to be mediated by a differentiation process. Maturation into late stages of biofilm development resulting in stable and robust structures may require the formation of a matrix of extracellular polymeric substances (EPS), which are most often assumed to consist...

  7. Stratified growth in Pseudomonas aeruginosa biofilms

    DEFF Research Database (Denmark)

    Werner, E.; Roe, F.; Bugnicourt, A.

    2004-01-01

    In this study, stratified patterns of protein synthesis and growth were demonstrated in Pseudomonas aeruginosa biofilms. Spatial patterns of protein synthetic activity inside biofilms were characterized by the use of two green fluorescent protein (GFP) reporter gene constructs. One construct...... of oxygen limitation in the biofilm. Oxygen microelectrode measurements showed that oxygen only penetrated approximately 50 mum into the biofilm. P. aeruginosa was incapable of anaerobic growth in the medium used for this investigation. These results show that while mature P. aeruginosa biofilms contain...

  8. Alcohol and tobacco consumption affects bacterial richness in oral cavity mucosa biofilms

    OpenAIRE

    Thomas, Andrew Maltez; Gleber-Netto, Frederico Omar; Fernandes, Gustavo Ribeiro; Amorim, Maria; Barbosa, Luisa Fernanda; Francisco, Ana Lúcia Noronha; Andrade,Arthur Guerra de; Setubal, João Carlos; Kowalski, Luiz Paulo; Nunes, Diana Noronha; Dias-Neto, Emmanuel

    2014-01-01

    Abstract Background Today there are more than 2 billion alcohol users and about 1.3 billion tobacco users worldwide. The chronic and heavy use of these two substances is at the heart of numerous diseases and may wreak havoc on the human oral microbiome. This study delves into the changes that alcohol and tobacco may cause on biofilms of the human oral microbiome. To do so, we used swabs to sample the oral biofilm of 22 subjects; includin...

  9. Oral hygiene frequency and presence of visible biofilm in the primary dentition

    OpenAIRE

    Santos,Ana Paula Pires dos; Séllos,Mariana Canano; Ramos,Maria Eliza Barbosa; Soviero,Vera Mendes

    2007-01-01

    The purpose of this study was to associate oral hygiene frequency and presence of visible biofilm in the primary dentition. The sample consisted of 90 children, aged up to 4 years old, outpatients of the University Hospital of the Rio de Janeiro State University. The examinations were carried out in a dental office by a single trained examiner who was aided by an assistant. The parents answered a structured questionnaire about oral hygiene methods and frequency. Two biofilm indices, one simpl...

  10. Effects of CO2 laser irradiation on tooth enamel coated with biofilm.

    Science.gov (United States)

    Cohen, Julie; Featherstone, John D B; Le, Charles Q; Steinberg, Doron; Feuerstein, Osnat

    2014-03-01

    CO2 laser irradiation of tooth enamel can inhibit demineralization of tooth enamel, by changing enamel composition and resistance to acid attack. The aim of this work was to examine these effects of CO2 laser irradiation on enamel covered by biofilm. Streptococcus mutans was grown on bovine enamel surfaces for 48 hours to form a mature biofilm. Samples were irradiated by CO2 laser (wavelength of 10.6 µm) at a power of 0.08 W in a super-pulse mode for 1 second and 24 pulses/second, with an energy density of 0.77 J/cm(2) per pulse. Untreated controls and laser treated samples with and without biofilm were examined for the morphology of the biofilm and the enamel surface by scanning electron microscopy (SEM). Structural biofilm viability was assessed using confocal laser scanning microscopy with live/dead staining. The biofilm was removed in a sonication water bath and the non-treated and irradiated enamel samples were chemically analyzed using energy dispersive X-ray spectrometry (EDS) and Fourier transform infrared spectroscopy (FTIR). Irradiated samples showed a melt zone with micro-cracks in the center of the irradiating beam position, which was smaller when irradiated enamel was covered by biofilm. Confocal microscopy images demonstrated higher proportion of dead bacteria at the margins of the irradiated spot area, while at the spot center the bacteria were evaporated exposing the enamel surface to direct laser irradiation. EDS analysis showed an increase in Ca/P ratio after irradiation of enamel covered with biofilm. FTIR analysis showed an approximately 40% carbonate loss in the irradiated enamel samples, including those with biofilms. Biofilms protect enamel surfaces from possible morphological irradiation damage without interfering with the resultant chemical changes that may increase the enamel resistance to acid attack. Therefore, under certain exposure regimens that are thermally and mechanically safe for enamel, CO2 laser irradiation of

  11. Anti-Biofilm and Antivirulence Activities of Metabolites from Plectosphaerella cucumerina against Pseudomonas aeruginosa

    Directory of Open Access Journals (Sweden)

    Jinwei Zhou

    2017-05-01

    Full Text Available This study reported the efficacy of the metabolites of Plectosphaerella cucumerina, one phyllosphere fungus from Orychophragmus violaceus, against Pseudomonas aeruginosa quorum sensing (QS and QS-regulated biofilms. The minimum inhibitory concentration (MIC of the ethyl acetate (EtOAc extract from P. cucumerina against P. aeruginosa PAO1 was 1.25 mg mL−1. At sub-MIC concentrations, P. cucumerina extract (0.25–1 mg mL−1 not only inhibited biofilm formation but also disrupted preformed biofilms of P. aeruginosa PAO1 without affecting its growth. Fluorescence and scanning electron microscope (SEM showed architectural disruption of the biofilms when treated with P. cucumerina metabolites. Further investigation demonstrated that metabolites in P. cucumerina attenuated the QS-dependent virulence factors. LC-MS/MS spectra coupled with experimentally standard samples suggested that patulin and emodin might act as the principal components possessing anti-biofilm and antivirulence activities. This is the first report of (1 the isolation of P. cucumerina from the phyllosphere of O. violaceus and (2 anti-biofilm, antivirulence, and biofilm disruption activities of this fungus. Thus, this study provides fascinating new pathways for screening antipathogenic agents.

  12. Anti-Biofilm and Antivirulence Activities of Metabolites fromPlectosphaerella cucumerinaagainstPseudomonas aeruginosa.

    Science.gov (United States)

    Zhou, Jinwei; Bi, Shiyuan; Chen, Hongjuan; Chen, Tongtong; Yang, Rui; Li, Minghui; Fu, Yonghong; Jia, Ai-Qun

    2017-01-01

    This study reported the efficacy of the metabolites of Plectosphaerella cucumerina , one phyllosphere fungus from Orychophragmus violaceus , against Pseudomonas aeruginosa quorum sensing (QS) and QS-regulated biofilms. The minimum inhibitory concentration (MIC) of the ethyl acetate (EtOAc) extract from P. cucumerina against P. aeruginosa PAO1 was 1.25 mg mL -1 . At sub-MIC concentrations, P. cucumerina extract (0.25-1 mg mL -1 ) not only inhibited biofilm formation but also disrupted preformed biofilms of P. aeruginosa PAO1 without affecting its growth. Fluorescence and scanning electron microscope (SEM) showed architectural disruption of the biofilms when treated with P. cucumerina metabolites. Further investigation demonstrated that metabolites in P. cucumerina attenuated the QS-dependent virulence factors. LC-MS/MS spectra coupled with experimentally standard samples suggested that patulin and emodin might act as the principal components possessing anti-biofilm and antivirulence activities. This is the first report of (1) the isolation of P. cucumerina from the phyllosphere of O. violaceus and (2) anti-biofilm, antivirulence, and biofilm disruption activities of this fungus. Thus, this study provides fascinating new pathways for screening antipathogenic agents.

  13. Species sorting during biofilm assembly by artificial substrates deployed in a cold seep system

    KAUST Repository

    Zhang, Wei Peng

    2014-10-17

    Studies focusing on biofilm assembly in deep-sea environments are rarely conducted. To examine the effects of substrate type on microbial community assembly, biofilms were developed on different substrates for different durations at two locations in the Red Sea: in a brine pool and in nearby bottom water (NBW) adjacent to the Thuwal cold seep II. The composition of the microbial communities in 51 biofilms and water samples were revealed by classification of pyrosequenced 16S rRNA gene amplicons. Together with the microscopic characteristics of the biofilms, the results indicate a stronger selection effect by the substrates on the microbial assembly in the brine pool compared with the NBW. Moreover, the selection effect by substrate type was stronger in the early stages compared with the later stages of the biofilm development. These results are consistent with the hypotheses proposed in the framework of species sorting theory, which states that the power of species sorting during microbial community assembly is dictated by habitat conditions, duration and the structure of the source community. Therefore, the results of this study shed light on the control strategy underlying biofilm-associated marine fouling and provide supporting evidence for ecological theories important for understanding the formation of deep-sea biofilms.

  14. Oral biofilms: molecular analysis, challenges, and future prospects in dental diagnostics

    Directory of Open Access Journals (Sweden)

    Do T

    2013-02-01

    Full Text Available Thuy Do,1 Deirdre Devine,1 Philip D Marsh1,21Department of Oral Biology, Leeds Dental Institute, Leeds, 2Health Protection Agency Microbiology Services, Salisbury, UKAbstract: Oral biofilms are functionally and structurally organized polymicrobial communities that are embedded in an extracellular matrix of exopolymers on mucosal and dental surfaces. These biofilms are found naturally in health, and provide benefits to the host. However, this relationship can break down, and disease can occur; disease is associated with a shift in the balance of the species within these biofilms. Simple diagnostic tests have been developed that involve the culture of selected bacteria, eg, those implicated in dental caries, facilitating an assessment of risk of further disease in individual patients. However, oral diseases have a complex etiology, and because only around 50% of oral biofilm can be grown at present, culture-independent molecular-based approaches are being developed that give a more comprehensive assessment of the presence of a range of putative pathogens in samples. The diversity of these biofilms creates challenges in the interpretation of findings, and future work is investigating the ability of novel techniques to detect biological activity and function in oral biofilms, rather than simply providing a catalogue of microbial names.Keywords: oral biofilms, dental plaque, dental diagnostics, molecular techniques, polymerase chain reaction, next-generation sequencing

  15. Arsenate Retention by Epipsammic Biofilms Developed on Streambed Sediments: Influence of Phosphate

    Directory of Open Access Journals (Sweden)

    D. M. Prieto

    2013-01-01

    Full Text Available Natural geological conditions together with the impact of human activities could produce environmental problems due to high As concentrations. The aim of this study was to assess the role of epipsammic biofilm-sediment systems onto As (V sorption and to evaluate the effect of the presence of equimolar P concentrations on As retention. A natural biofilm was grown on sediment samples in the laboratory, using river water as nutrient supplier. Sorption experiments with initial As concentrations 0, 5, 25, 50, 100, 250, and 500 μg L−1 were performed. The average percentage of As sorbed was 78.9±3.5 and 96.9±6.6% for the sediment and biofilm-sediment systems, respectively. Phosphate decreased by 25% the As sorption capactity in the sediment devoid of biofilm, whereas no significant effect was observed in the systems with biofilm. Freundlich, Sips, and Toth models were the best to describe experimental data. The maximum As sorption capacity of the sediment and biofilm-sediment systems was, respectively, 6.6 and 6.8 μg g−1 and 4.5 and 7.8 μg g−1 in the presence of P. In conclusion, epipsammic biofilms play an important role in the environmental quality of river systems, increasing As retention by the system, especially in environments where both As and P occur simultaneously.

  16. Bioreactor plant for the reproducible building of biofilms; Bioreaktoranlage zur reproduzierbaren Bildung von Biofilmen

    Energy Technology Data Exchange (ETDEWEB)

    Scheen, J. [Dortmund Univ. (Germany). Inst. fuer Umweltforschung

    1998-10-01

    Biofilms frequently appear, they are sometimes useful and sometimes disturbing. For the investigation of biofilms, it was necessary to reproduce them in specific bioreactors. Furthermore, useful media and analytical methods have to define the influence of biocides and other substances. The gravimetric analysis of microbe-formed polysaccharides in water samples and biofilm makes it possible to recognise successful treatments. These conditions are described here. Using these instruments it was possible to build up reproducible biofilms, to test and optimise them in lab examinations. In view of the expected EU Biocide Directive, this process offers possibilities for searching and verifying the suitability of biocides and other substances. (orig.) [Deutsch] Biofilme treten vielfach, sowohl nuetzlich - als auch stoerend, auf. Fuer die Untersuchungen an Biofilmen wurde eine Bioreaktoranlage, ein synthetisches Medium und eine aussagekraeftige Analytik entwickelt. Mit der gravimetrischen Messung von mikrobiell gebildeten Exopolysacchariden, aus der waessrigen Phase und direkt aus dem Biofilm heraus, konnte die Bildung von Biofilmen verfolgt werden. Mit diesem Instrumentarium war es moeglich, Biofilme reproduzierbar zu bilden und die nuetzlichen als auch schaedlichen Eigenschaften von Biofilmen im Labor zu testen und zu optimieren. Dadurch koennen Foerder- als auch Vermeidungsmethoden durch z.B. Biozide oder andere Wirkstoffe besser beurteilt werden. Im Hinblick auf die zu erwartende EU-Biozid-Richtlinie bieten sich guenstige Untersuchungsmoeglichkeiten von Bioziden auf ihre Praxistauglichkeit an. (orig.)

  17. Effect of bacteriocin and exopolysaccharides isolated from probiotic on P. aeruginosa PAO1 biofilm.

    Science.gov (United States)

    Sharma, Vivek; Harjai, Kusum; Shukla, Geeta

    2017-09-14

    Microorganisms develop biofilms on indwelling medical devices and are associated with biofilm-related infections, resulting in substantial morbidity and mortality. Therefore, to prevent and control biofilm-associated infections, the present study was designed to assess the anti-biofilm potential of postbiotics derived from probiotic organisms against most prevalent biofilm-forming Pseudomonas aeruginosa PAO1. Eighty lactic acid bacteria isolated from eight neonatal fecal samples possessed antibacterial activity against P. aeruginosa PAO1. Among these, only four lactic acid bacteria produced both bacteriocin and exopolysaccharides but only one isolate was found to maximally attenuate the P. aeruginosa PAO1 biofilm. More specifically, the phenotypic and probiotic characterization showed that the isolated lactic acid bacteria were gram positive, non-motile, and catalase and oxidase negative; tolerated acidic and alkaline pH; has bile salt concentration; showed 53% hydrophobicity; and was found to be non-hemolytic. Phylogenetically, the organism was found to be probiotic Lactobacillus fermentum with accession no. KT998657. Interestingly, pre-coating of a microtiter plate either with bacteriocin or with exopolysaccharides as well as their combination significantly (p postbiotics that had 72.4% biofilm-forming viable cells as observed by flow cytometry and confocal laser scanning microscopy. Therefore, it can be anticipated that postbiotics as the natural biointerventions can be employed as the prophylactic agents for medical devices used to treat gastrointestinal and urinary tract infections.

  18. Inhibition of multispecies biofilms by a fluoride-releasing dental prosthesis copolymer.

    Science.gov (United States)

    Yassin, Sufian A; German, Matthew J; Rolland, Sarah L; Rickard, Alexander H; Jakubovics, Nicholas S

    2016-05-01

    This study aimed to develop a new mixed-species acidogenic biofilm model and use it to assess the antimicrobial properties of a novel fluoride-releasing copolymer. Stubs composed of a copolymer of methyl methacrylate (MMA) and 2-hydroxyethyl methacrylate (HEMA) with polymethyl methacrylate (PMMA) were produced by chemically-activated free radical polymerization. A fluoride-releasing copolymer was developed by incorporating sodium fluoride in place of a portion of the PMMA. Samples were mounted in polysulfone Modified Robbins Devices (MRDs) and were optimized for single- and mixed-species biofilm formation by Candida albicans, Lactobacillus casei and Streptococcus mutans. Fluoride release was sustained for at least 48h in flowing conditions. Fluoride did not affect the colonization and biofilm growth of any of the microorganisms in monocultures. However, in mixed-species biofilms, cell densities of all three species were reduced approximately ten-fold (pbiofilms are sensitive to fluoride, and that the inclusion of fluoride in a denture lining copolymer reduces the formation of polymicrobial biofilms. The growth of acidogenic microorganisms on denture materials is associated with denture stomatitis and dental caries on surrounding teeth. A fluoride-releasing copolymer that inhibits acidogenic mixed-species biofilms, such as the material described in this study, has the potential to control these diseases by limiting biofilm growth. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. Study on E. coli and Salmonella biofilms from fresh fruits and vegetables.

    Science.gov (United States)

    Amrutha, Balagopal; Sundar, Kothandapani; Shetty, Prathapkumar Halady

    2017-04-01

    Foodborne outbreaks associated with fresh fruits and vegetables are on the rise worldwide. Biofilm formation is one of the important traits of pathogens making them strongly attached to substrates as well as express virulence phenotypes. Present study investigates the biofilm forming ability of E. coli and Salmonella sp. isolated from fresh fruits and vegetables. A total of 53 strains, including 35 E. coli and 18 Salmonella sp. isolated from different fruit and vegetable samples were taken into account for the study. Initial screening for biofilm formation was done using Congo Red agar plate test. Results revealed that 22.8% E. coli and 22.2% Salmonella sp. were potential biofilm formers. However, the MTP (Micro-Titre Plate) assay suggested more isolates of both E. coli and Salmonella sp. were moderate to strong biofilm producers. Agar plate diffusion assay with Agrobacterium tumefaciens NTL-4 showed the production of quorum signaling molecules (AHLs) by three isolates of E. coli and one Salmonella sp. Two E. coli isolates showed a significant amount of EPS production indicating higher biofilm forming potential. The Presence of LUX R homologue gene (sdiA) in two of the Salmonella isolates were confirmed by PCR which demonstrated their potential pathogenicity. Results of the work underline the biofilm forming and potentially virulent capacities of isolates from the surface of fruits and vegetables.

  20. Environmental switching during biofilm development in a cold seep system and functional determinants of species sorting

    KAUST Repository

    Zhang, Weipeng

    2015-11-28

    The functional basis for species sorting theory remains elusive, especially for microbial community assembly in deep sea environments. Using artificial surface-based biofilm models, our recent work revealed taxonomic succession during biofilm development in a newly defined cold seep system, the Thuwal cold seeps II, which comprises a brine pool and the adjacent normal bottom water (NBW) to form a metacommunity via the potential immigration of organisms from one patch to another. Here, we designed an experiment to investigate the effects of environmental switching between the brine pool and the NBW on biofilm assembly, which could reflect environmental filtering effects during bacterial immigration to new environments. Analyses of 16S rRNA genes of 71 biofilm samples suggested that the microbial composition of biofilms established in new environments was determined by both the source community and the incubation conditions. Moreover, a comparison of 18 metagenomes provided evidence for biofilm community assembly that was based primarily on functional features rather than taxonomic identities; metal ion resistance and amino acid metabolism were the major species sorting determinants for the succession of biofilm communities. Genome binning and pathway reconstruction of two bacterial species (Marinobacter sp. and Oleispira sp.) further demonstrated metal ion resistance and amino acid metabolism as functional traits conferring the survival of habitat generalists in both the brine pool and NBW. The results of the present study sheds new light on microbial community assembly in special habitats and bridges a gap in species sorting theory.

  1. Arsenate retention by epipsammic biofilms developed on streambed sediments: influence of phosphate.

    Science.gov (United States)

    Prieto, D M; Devesa-Rey, R; Rubinos, D A; Díaz-Fierros, F; Barral, M T

    2013-01-01

    Natural geological conditions together with the impact of human activities could produce environmental problems due to high As concentrations. The aim of this study was to assess the role of epipsammic biofilm-sediment systems onto As (V) sorption and to evaluate the effect of the presence of equimolar P concentrations on As retention. A natural biofilm was grown on sediment samples in the laboratory, using river water as nutrient supplier. Sorption experiments with initial As concentrations 0, 5, 25, 50, 100, 250, and 500  μg L(-1) were performed. The average percentage of As sorbed was 78.9 ± 3.5 and 96.9 ± 6.6% for the sediment and biofilm-sediment systems, respectively. Phosphate decreased by 25% the As sorption capactity in the sediment devoid of biofilm, whereas no significant effect was observed in the systems with biofilm. Freundlich, Sips, and Toth models were the best to describe experimental data. The maximum As sorption capacity of the sediment and biofilm-sediment systems was, respectively, 6.6 and 6.8  μg g(-1) and 4.5 and 7.8  μg g(-1) in the presence of P. In conclusion, epipsammic biofilms play an important role in the environmental quality of river systems, increasing As retention by the system, especially in environments where both As and P occur simultaneously.

  2. Focusing on Environmental Biofilms With Variable-Pressure Scanning Electron Microscopy

    Science.gov (United States)

    Joubert, L.; Wolfaardt, G. M.; Du Plessis, K.

    2006-12-01

    Since the term biofilm has been coined almost 30 years ago, visualization has formed an integral part of investigations on microbial attachment. Electron microscopic (EM) biofilm studies, however, have been limited by the hydrated extracellular matrix which loses structural integrity with conventional preparative techniques, and under required high-vacuum conditions, resulting in a loss of information on spatial relationships and distribution of biofilm microbes. Recent advances in EM technology enable the application of Variable Pressure Scanning Electron Microscopy (VP SEM) to biofilms, allowing low vacuum and hydrated chamber atmosphere during visualization. Environmental biofilm samples can be viewed in situ, unfixed and fully hydrated, with application of gold-sputter-coating only, to increase image resolution. As the impact of microbial biofilms can be both hazardous and beneficial to man and his environment, recognition of biofilms as a natural form of microbial existence is needed to fully assess the potential role of microbial communities on technology. The integration of multiple techniques to elucidate biofilm processes has become imperative for unraveling complex phenotypic adaptations of this microbial lifestyle. We applied VP SEM as integrative technique with traditional and novel analytical techniques to (1)localize lignocellulosic microbial consortia applied for producing alternative bio-energy sources in the mining wastewater industry, (2) characterize and visualize wetland microbial communities in the treatment of winery wastewater, and (3)determine the impact of recombinant technology on yeast biofilm behavior. Visualization of microbial attachment to a lignocellulose substrate, and degradation of exposed plant tissue, gave insight into fiber degradation and volatile fatty acid production for biological sulphate removal from mining wastewater. Also, the 3D-architecture of complex biofilms developing in constructed wetlands was correlated with

  3. Combining Biofilm-Controlling Compounds and Antibiotics as a Promising New Way to Control Biofilm Infections

    Directory of Open Access Journals (Sweden)

    Andréia Bergamo Estrela

    2010-05-01

    Full Text Available Many bacteria grow on surfaces forming biofilms. In this structure, they are well protected and often high dosages of antibiotics cannot clear infectious biofilms. The formation and stabilization of biofilms are mediated by diffusible autoinducers (e.g. N-acyl homoserine lactones, small peptides, furanosyl borate diester. Metabolites interfering with this process have been identified in plants, animals and microbes, and synthetic analogues are known. Additionally, this seems to be not the only way to control biofilms. Enzymes capable of cleaving essential components of the biofilm matrix, e.g. polysaccharides or extracellular DNA, and thus weakening the biofilm architecture have been identified. Bacteria also have mechanisms to dissolve their biofilms and return to planktonic lifestyle. Only a few compounds responsible for the signalling of these processes are known, but they may open a completely novel line of biofilm control. All these approaches lead to the destruction of the biofilm but not the killing of the pathogens. Therefore, a combination of biofilm-destroying compounds and antibiotics to handle biofilm infections is proposed. In this article, different approaches to combine biofilm-controlling compounds and antibiotics to fight biofilm infections are discussed, as well as the balance between biofilm formation and virulence.

  4. Extracellular DNA Contributes to Dental Biofilm Stability

    DEFF Research Database (Denmark)

    Schlafer, Sebastian; Meyer, Rikke Louise; Dige, Irene

    2017-01-01

    dental biofilms. This study aimed to determine whether eDNA was part of the matrix in biofilms grown in situ in the absence of sucrose and whether treatment with DNase dispersed biofilms grown for 2.5, 5, 7.5, 16.5, or 24 h. Three hundred biofilms from 10 study participants were collected and treated...... the amount of biofilm in very early stages of growth (up to 7.5 h), but the treatment effect decreased with increasing biofilm age. This study proves the involvement of eDNA in dental biofilm formation and its importance for biofilm stability in the earliest stages. Further research is required to uncover......Extracellular DNA (eDNA) is a major matrix component of many bacterial biofilms. While the presence of eDNA and its role in biofilm stability have been demonstrated for several laboratory biofilms of oral bacteria, there is no data available on the presence and function of eDNA in in vivo grown...

  5. Phytochemicals as Inhibitors of Candida Biofilm.

    Science.gov (United States)

    Raut, Jayant Shankar; Karuppayil, Sankunny Mohan

    2016-01-01

    Candida biofilm and associated infections is a serious threat to the large population of immunocompromised patients. Biofilm growth on prosthetic devices or host tissue shows reduced sensitivity to antifungal agents and persists as a reservoir of infective cells. Options for successful treatment of biofilm associated Candida infections are restricted because most of the available antifungal drugs fail to eradicate biofilms. Various plant actives are known to possess interesting antifungal properties. To explore and review the potential of phytochemicals as a novel strategy against Candida biofilms is the intent of present article. Thorough literature search is performed to identify Candida biofilm inhibitors of plant origin. An account of efficacy of selected phytochemicals is presented taking into consideration their biofilm inhibitory concentrations. This review discusses biofilm formation by Candida species, their involvement in human infections, and associated drug resistance. It gives insight into the biofilm inhibitory potential of various phytochemicals. Based on the available reports including the work done in our laboratory, several plant extracts, essential oils and phytomolecules have been identified as excellent inhibitors of biofilms of C. albicans and non-albicans Candida species (NACS). Selected phytochemicals which exhibit activities at low concentrations without displaying toxicity to host are potential therapeutic agents against biofilm associated Candida infections. In vivo testing in animal models and clinical trials in humans are required to be taken up seriously to propose few of the phytochemicals as candidate drug molecules.

  6. Biofilm induced tolerance towards antimicrobial peptides.

    Directory of Open Access Journals (Sweden)

    Anders Folkesson

    Full Text Available Increased tolerance to antimicrobial agents is thought to be an important feature of microbes growing in biofilms. We address the question of how biofilm organization affects antibiotic susceptibility. We established Escherichia coli biofilms with differential structural organization due to the presence of IncF plasmids expressing altered forms of the transfer pili in two different biofilm model systems. The mature biofilms were subsequently treated with two antibiotics with different molecular targets, the peptide antibiotic colistin and the fluoroquinolone ciprofloxacin. The dynamics of microbial killing were monitored by viable count determination, and confocal laser microscopy. Strains forming structurally organized biofilms show an increased bacterial survival when challenged with colistin, compared to strains forming unstructured biofilms. The increased survival is due to genetically regulated tolerant subpopulation formation and not caused by a general biofilm property. No significant difference in survival was detected when the strains were challenged with ciprofloxacin. Our data show that biofilm formation confers increased colistin tolerance to cells within the biofilm structure, but the protection is conditional being dependent on the structural organization of the biofilm, and the induction of specific tolerance mechanisms.

  7. Biofilms of vaginal Lactobacillus in vitro test.

    Science.gov (United States)

    Wei, Xiao-Yu; Zhang, Rui; Xiao, Bing-Bing; Liao, Qin-Ping

    2017-01-01

    This paper focuses on biofilms of Lactobacillus spp. - a type of normal flora isolated from healthy human vaginas of women of childbearing age; thereupon, it broadens the research scope of investigation of vaginal normal flora. The static slide culture method was adopted to foster biofilms, marked by specific fluorescence staining. Laser scanning confocal and scanning electron microscopy were used to observe the microstructure of the biofilms. Photographs taken from the microstructure were analysed to calculate the density of the biofilms. The body of Lactobacillus spp., though red, turned yellow when interacting with the green extracellular polysaccharides. The structure of the biofilm and aquaporin within the biofilm were imaged. Lactobacillus density increases over time. This study provides convincing evidence that Lactobacillus can form biofilms and grow over time in vitro. This finding establishes an important and necessary condition for selecting proper strains for the pharmaceutics of vaginal ecology.

  8. Cell death in Pseudomonas aeruginosa biofilm development

    DEFF Research Database (Denmark)

    Webb, J.S.; Thompson, L.S.; James, S.

    2003-01-01

    Bacteria growing in biofilms often develop multicellular, three-dimensional structures known as microcolonies. Complex differentiation within biofilms of Pseudomonas aeruginosa occurs, leading to the creation of voids inside microcolonies and to the dispersal of cells from within these voids....... However, key developmental processes regulating these events are poorly understood. A normal component of multicellular development is cell death. Here we report that a repeatable pattern of cell death and lysis occurs in biofilms of P. aeruginosa during the normal course of development. Cell death...... occurred with temporal and spatial organization within biofilms, inside microcolonies, when the biofilms were allowed to develop in continuous-culture flow cells. A subpopulation of viable cells was always observed in these regions. During the onset of biofilm killing and during biofilm development...

  9. Biofilm formation by Borrelia burgdorferi sensu lato.

    Science.gov (United States)

    Timmaraju, Venkata Arun; Theophilus, Priyanka A S; Balasubramanian, Kunthavai; Shakih, Shafiq; Luecke, David F; Sapi, Eva

    2015-08-01

    Bacterial biofilms are microbial communities held together by an extracellular polymeric substance matrix predominantly composed of polysaccharides, proteins and nucleic acids. We had previously shown that Borrelia burgdorferi sensu stricto, the causative organism of Lyme disease in the United States is capable of forming biofilms in vitro. Here, we investigated biofilm formation by B. afzelii and B. garinii, which cause Lyme disease in Europe. Using various histochemistry and microscopy techniques, we show that B. afzelii and B. garinii form biofilms, which resemble biofilms formed by B. burgdorferi sensu stricto. High-resolution atomic force microscopy revealed similarities in the ultrastructural organization of the biofilms form by three Borrelia species. Histochemical experiments revealed a heterogeneous organization of exopolysaccharides among the three Borrelia species. These results suggest that biofilm formation might be a common trait of Borrelia genera physiology. © FEMS 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  10. Molecular Basis for Saccharomyces cerevisiae Biofilm Development

    DEFF Research Database (Denmark)

    Andersen, Kaj Scherz

    of translation of FLO11. In conclusion, I have conducted the first global study of the genetic program for yeast biofilm formation on polystyrene. This work provide several target genes as good basis for further research of biofilm, that I believe can contribute to fields such as cell biology, genetics, system......In this study, I sought to identify genes regulating the global molecular program for development of sessile multicellular communities, also known as biofilm, of the eukaryotic microorganism, Saccharomyces cerevisiae (yeast). Yeast biofilm has a clinical interest, as biofilms can cause chronic......, but only a small subset is previously described as regulators of FLO11. These results reveal that the regulation of biofilm formation and FLO11 is even more complex than what has previously been described. I find that the molecular program for biofilm formation shares many essential components with two...

  11. Vibrio cholerae Biofilms and Cholera Pathogenesis.

    Directory of Open Access Journals (Sweden)

    Anisia J Silva

    2016-02-01

    Full Text Available Vibrio cholerae can switch between motile and biofilm lifestyles. The last decades have been marked by a remarkable increase in our knowledge of the structure, regulation, and function of biofilms formed under laboratory conditions. Evidence has grown suggesting that V. cholerae can form biofilm-like aggregates during infection that could play a critical role in pathogenesis and disease transmission. However, the structure and regulation of biofilms formed during infection, as well as their role in intestinal colonization and virulence, remains poorly understood. Here, we review (i the evidence for biofilm formation during infection, (ii the coordinate regulation of biofilm and virulence gene expression, and (iii the host signals that favor V. cholerae transitions between alternative lifestyles during intestinal colonization, and (iv we discuss a model for the role of V. cholerae biofilms in pathogenicity.

  12. A short history of microbial biofilms and biofilm infections

    DEFF Research Database (Denmark)

    Høiby, Niels

    2017-01-01

    The observation of aggregated microbes surrounded by a self-produced matrix adhering to surfaces or located in tissues or secretions is old since both Leeuwenhoek and Pasteur have described the phenomenon. In environmental and technical microbiology, biofilms, 80–90 years ago, were already shown ...

  13. Gene Transfer Efficiency in Gonococcal Biofilms: Role of Biofilm Age, Architecture, and Pilin Antigenic Variation.

    Science.gov (United States)

    Kouzel, Nadzeya; Oldewurtel, Enno R; Maier, Berenike

    2015-07-01

    Extracellular DNA is an important structural component of many bacterial biofilms. It is unknown, however, to which extent external DNA is used to transfer genes by means of transformation. Here, we quantified the acquisition of multidrug resistance and visualized its spread under selective and nonselective conditions in biofilms formed by Neisseria gonorrhoeae. The density and architecture of the biofilms were controlled by microstructuring the substratum for bacterial adhesion. Horizontal transfer of antibiotic resistance genes between cocultured strains, each carrying a single resistance, occurred efficiently in early biofilms. The efficiency of gene transfer was higher in early biofilms than between planktonic cells. It was strongly reduced after 24 h and independent of biofilm density. Pilin antigenic variation caused a high fraction of nonpiliated bacteria but was not responsible for the reduced gene transfer at later stages. When selective pressure was applied to dense biofilms using antibiotics at their MIC, the double-resistant bacteria did not show a significant growth advantage. In loosely connected biofilms, the spreading of double-resistant clones was prominent. We conclude that multidrug resistance readily develops in early gonococcal biofilms through horizontal gene transfer. However, selection and spreading of the multiresistant clones are heavily suppressed in dense biofilms. Biofilms are considered ideal reaction chambers for horizontal gene transfer and development of multidrug resistances. The rate at which genes are exchanged within biofilms is unknown. Here, we quantified the acquisition of double-drug resistance by gene transfer between gonococci with single resistances. At early biofilm stages, the transfer efficiency was higher than for planktonic cells but then decreased with biofilm age. The surface topography affected the architecture of the biofilm. While the efficiency of gene transfer was independent of the architecture, spreading of

  14. Biofilm monitoring using complex permittivity.

    Energy Technology Data Exchange (ETDEWEB)

    Altman, Susan Jeanne; McGrath, Lucas K.; Dolan, Patricia L.; Yelton, William Graham

    2008-10-01

    There is strong interest in the detection and monitoring of bio-fouling. Bio-fouling problems are common in numerous water treatments systems, medical and dental apparatus and food processing equipment. Current bio-fouling control protocols are time consuming and costly. New early detection techniques to monitor bio-forming contaminates are means to enhanced efficiency. Understanding the unique dielectric properties of biofilm development, colony forming bacteria and nutrient background will provide a basis to the effectiveness of controlling or preventing biofilm growth. Dielectric spectroscopy measurements provide values of complex permittivity, {var_epsilon}*, of biofilm formation by applying a weak alternating electric field at various frequencies. The dielectric characteristic of the biofilm, {var_epsilon}{prime}, is the real component of {var_epsilon}* and measures the biofilm's unique ability to store energy. Graphically observed dependencies of {var_epsilon}{prime} to frequency indicate dielectric relaxation or dielectric dispersion behaviors that mark the particular stage of progression during the development of biofilms. In contrast, any frequency dependency of the imaginary component, {var_epsilon}{double_prime} the loss factor, is expressed as dielectric losses from the biofilm due to dipole relaxation. The tangent angle of these two component vectors is the ratio of the imaginary component to the real component, {var_epsilon}{double_prime}/{var_epsilon}{prime} and is referred to as the loss angle tangent (tan {delta}) or dielectric loss. Changes in tan {delta} are characteristic of changes in dielectric losses during various developmental stages of the films. Permittivity scans in the above figure are of biofilm growth from P. Fluorescens (10e7 CFU's at the start). Three trends are apparent from these scans, the first being a small drop in the imaginary permittivity over a 7 hours period, best seen in the Cole-Cole plot (a). The second trend

  15. Endotracheal tube biofilm translocation in the lateral Trendelenburg position.

    Science.gov (United States)

    Li Bassi, Gianluigi; Fernandez-Barat, Laia; Saucedo, Lina; Giunta, Valeria; Marti, Joan Daniel; Tavares Ranzani, Otavio; Aguilera Xiol, Eli; Rigol, Montserrat; Roca, Ignasi; Muñoz, Laura; Luque, Nestor; Esperatti, Mariano; Saco, Maria Adela; Ramirez, Jose; Vila, Jordi; Ferrer, Miguel; Torres, Antoni

    2015-02-27

    Laboratory studies demonstrated that the lateral Trendelenburg position (LTP) is superior to the semirecumbent position (SRP) in the prevention of ventilator-associated pulmonary infections. We assessed whether the LTP could also prevent pulmonary colonization and infections caused by an endotracheal tube (ETT) biofilm. Eighteen pigs were intubated with ETTs colonized by Pseudomonas aeruginosa biofilm. Pigs were positioned in LTP and randomized to be on mechanical ventilatin (MV) up to 24 hour, 48 hour, 48 hour with acute lung injury (ALI) by oleic acid and 72 hour. Bacteriologic and microscopy studies confirmed presence of biofilm within the ETT. Upon autopsy, samples from the proximal and distal airways were excised for P.aeruginosa quantification. Ventilator-associated tracheobronchitis (VAT) was confirmed by bronchial tissue culture ≥3 log colony forming units per gram (cfu/g). In pulmonary lobes with gross findings of pneumonia, ventilator-associated pneumonia (VAP) was confirmed by lung tissue culture ≥3 log cfu/g. P.aeruginosa colonized the internal lumen of 16 out of 18 ETTs (88.89%), and a mature biofilm was consistently present. P.aeruginosa colonization did not differ among groups, and was found in 23.6% of samples from the proximal airways, and in 7.1% from the distal bronchi (P = 0.001). Animals of the 24 hour group never developed respiratory infections, whereas 20%, 60% and 25% of the animals in group 48 hour, 48 hour-ALI and 72 hour developed P.aeruginosa VAT, respectively (P = 0.327). Nevertheless, VAP never developed. Our findings imply that during the course of invasive MV up to 72 hour, an ETT P.aeruginosa biofilm hastily colonizes the respiratory tract. Yet, the LTP compartmentalizes colonization and infection within the proximal airways and VAP never develops.

  16. Dynamics of Biofilm Regrowth in Drinking Water Distribution Systems.

    Science.gov (United States)

    Douterelo, I; Husband, S; Loza, V; Boxall, J

    2016-07-15

    The majority of biomass within water distribution systems is in the form of attached biofilm. This is known to be central to drinking water quality degradation following treatment, yet little understanding of the dynamics of these highly heterogeneous communities exists. This paper presents original information on such dynamics, with findings demonstrating patterns of material accumulation, seasonality, and influential factors. Rigorous flushing operations repeated over a 1-year period on an operational chlorinated system in the United Kingdom are presented here. Intensive monitoring and sampling were undertaken, including time-series turbidity and detailed microbial analysis using 16S rRNA Illumina MiSeq sequencing. The results show that bacterial dynamics were influenced by differences in the supplied water and by the material remaining attached to the pipe wall following flushing. Turbidity, metals, and phosphate were the main factors correlated with the distribution of bacteria in the samples. Coupled with the lack of inhibition of biofilm development due to residual chlorine, this suggests that limiting inorganic nutrients, rather than organic carbon, might be a viable component in treatment strategies to manage biofilms. The research also showed that repeat flushing exerted beneficial selective pressure, giving another reason for flushing being a viable advantageous biofilm management option. This work advances our understanding of microbiological processes in drinking water distribution systems and helps inform strategies to optimize asset performance. This research provides novel information regarding the dynamics of biofilm formation in real drinking water distribution systems made of different materials. This new knowledge on microbiological process in water supply systems can be used to optimize the performance of the distribution network and to guarantee safe and good-quality drinking water to consumers. Copyright © 2016 Douterelo et al.

  17. Exopolymeric substances from drinking water biofilms: Dynamics of production and relation with disinfection by products.

    Science.gov (United States)

    Lemus Pérez, M F; Rodríguez Susa, M

    2017-06-01

    Exopolymeric substances (EPS) as an external matrix of biofilm could react with disinfectants in drinking water networks forming disinfection by-products (DBP). Based on an experimental setup using two chlorine conditions-biofilm 1 (2.6 ± 0.8 mgCl/L) and biofilm 2 (0.7 ± 0.2 mg Cl/L)-samples of biofilms were recovered during 9 campaigns and EPS were extracted. Analyses of SUVA, fluorescence and amino acid (AA) content were carried out on the EPS to observe variation over time and correlations with DBP formation potential (DBPfp) after chlorination. SUVA values were under 2 L/mgC*m showing that both EPS were hydrophilic. Slightly higher SUVA in biofilm 2 with low variation over time was observed. Fluorescence showed that aromatic proteins and fulvic like substances were the principal components and increased in biofilm 1 over time. AA decreased with time, and higher values of alanine, threonine, proline and isoleucine were observed in biofilm 2. Based on general associations, the SUVA of biofilm 2 correlated well with chloroform (CF) (r = 0.80). Generally, in both biofilms, tryptophan-like substances were negatively correlated with DBP while humic acid-like substances correlated positively, but with low indexes (r = 0.3-0.6). Correlations of data from individual sampling increased the indices (r over 0.8), suggesting a temporal influence of other factors on DBPfp such as inorganics, filtered water and the structural composition of EPS. In biofilm 1, Br-haloacetic acids (Br-HAA), dibromoacetonitrile and bromochloro acetonitrile were inversely associated with arginine and valine, as were di and trichloropropanone to arginine. On the contrary, in biofilm 2, the following amino acids correlated positively with DBP: alanine with Br-HAA, alanine with CF, alanine with N-DBP (chloropicrin, di and tri-chloro acetonitrile), and valine with CF. As this is the first report about the relation between temporal variation of EPS and DBPfp of biofilms in two different

  18. Rapid identification of bacterial biofilms and biofilm wound models using a multichannel nanosensor.

    Science.gov (United States)

    Li, Xiaoning; Kong, Hao; Mout, Rubul; Saha, Krishnendu; Moyano, Daniel F; Robinson, Sandra M; Rana, Subinoy; Zhang, Xinrong; Riley, Margaret A; Rotello, Vincent M

    2014-12-23

    Identification of infectious bacteria responsible for biofilm-associated infections is challenging due to the complex and heterogeneous biofilm matrix. To address this issue and minimize the impact of heterogeneity on biofilm identification, we developed a gold nanoparticle (AuNP)-based multichannel sensor to detect and identify biofilms based on their physicochemical properties. Our results showed that the sensor can discriminate six bacterial biofilms including two composed of uropathogenic bacteria. The capability of the sensor was further demonstrated through discrimination of biofilms in a mixed bacteria/mammalian cell in vitro wound model.

  19. Biofilms and planktonic cells of Deinococcus geothermalis in extreme environments

    Science.gov (United States)

    Panitz, Corinna; Reitz, Guenther; Rabbow, Elke; Rettberg, Petra; Flemming, Hans-Curt; Wingender, Jost; Froesler, Jan

    In addition to the several extreme environments on Earth, Space can be considered as just another exceptional environment with a unique mixture of stress factors comprising UV radiation, vacuum, desiccation, temperature, ionizing radiation and microgravity. Life that processes in these environments can depend on the life forms and their state of living. The question is whether there are different strategies for individual microorganisms compared to communities of the same organisms to cope with the different factors of their surroundings. Comparative studies of the survi-val of these communities called biofilms and planktonic cell samples of Deinococcus geothermalis stand at the focal point of the presented investigations. A biofilm is a structured community of microorganisms that live encapsulated in a matrix of extracellular polymeric substances on a surface. Microorganisms living in a biofilm usually have significantly different properties to cooperate than individually living microorganisms of the same species. An advantage of the biofilm is increased resistance to various chemical and physical effects, while the dense extracellular matrix and the outer layer of the cells protect the interior of the microbial consortium. The space experiment BOSS (Biofilm organisms surfing Space) as part the ESA experimental unit EXPOSE R-2 with a planned launch date in July 2014 will be subsequently mounted on the Russian Svesda module outside the ISS. An international team of scientists coordinated by Dr. P. Rettberg will investigate the hypothesis whether microorganisms organized as biofilm outmatch the same microorganisms exposed individually in the long-term survival of the harsh environmental conditions as they occur in space and on Mars. Another protective function in the samples could be dust par-ticles for instance Mars regolith simulant contained inside the biofilms or mixed with the planktonic cells, as additional shelter especially against the extraterrestrial UV

  20. A novel technique using potassium permanganate and reflectance confocal microscopy to image biofilm extracellular polymeric matrix reveals non-eDNA networks in Pseudomonas aeruginosa biofilms.

    Science.gov (United States)

    Swearingen, Matthew C; Mehta, Ajeet; Mehta, Amar; Nistico, Laura; Hill, Preston J; Falzarano, Anthony R; Wozniak, Daniel J; Hall-Stoodley, Luanne; Stoodley, Paul

    2016-02-01

    Biofilms are etiologically important in the development of chronic medical and dental infections. The biofilm extracellular polymeric substance (EPS) determines biofilm structure and allows bacteria in biofilms to adapt to changes in mechanical loads such as fluid shear. However, EPS components are difficult to visualize microscopically because of their low density and molecular complexity. Here, we tested potassium permanganate, KMnO4, for use as a non-specific EPS contrast-enhancing stain using confocal laser scanning microscopy in reflectance mode. We demonstrate that KMnO4 reacted with EPS components of various strains of Pseudomonas, Staphylococcus and Streptococcus, yielding brown MnO2 precipitate deposition on the EPS, which was quantifiable using data from the laser reflection detector. Furthermore, the MnO2 signal could be quantified in combination with fluorescent nucleic acid staining. COMSTAT image analysis indicated that KMnO4 staining increased the estimated biovolume over that determined by nucleic acid staining alone for all strains tested, and revealed non-eDNA EPS networks in Pseudomonas aeruginosa biofilm. In vitro and in vivo testing indicated that KMnO4 reacted with poly-N-acetylglucosamine and Pseudomonas Pel polysaccharide, but did not react strongly with DNA or alginate. KMnO4 staining may have application as a research tool and for diagnostic potential for biofilms in clinical samples. © FEMS 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  1. Linezolid limits burden of methicillin-resistant Staphylococcus aureus in biofilm of tracheal tubes.

    Science.gov (United States)

    Fernández-Barat, Laia; Ferrer, Miquel; Sierra, Josep Maria; Soy, Dolors; Guerrero, Laura; Vila, Jordi; Li Bassi, Gianluigi; Cortadellas, Núria; Martínez-Olondris, Pilar; Rigol, Montserrat; Esperatti, Mariano; Luque, Néstor; Saucedo, Lina María; Agustí, Carlos; Torres, Antoni

    2012-08-01

    To evaluate the effects of systemic treatment with linezolid compared with vancomycin on biofilm formation in mechanically ventilated pigs with severe methicillin-resistant Staphylococcus aureus-induced pneumonia. Prospective randomized animal study. Departments of Pneumology, Microbiology, and Pharmacy of the Hospital Clínic, Barcelona, and Scientific and Technological Services of the University of Barcelona. We prospectively analyzed 70 endotracheal tube samples. Endotracheal tubes were obtained from pigs either untreated (controls, n=20), or treated with vancomycin (n=32) or linezolid (n=18). The endotracheal tubes were obtained from a previous randomized study in tracheally intubated pigs with methicillin-resistant Staphylococcus aureus severe pneumonia, and mechanically ventilated for 69±16 hrs. Distal and medial hemisections of the endotracheal tube were assessed to quantify methicillin-resistant Staphylococcus aureus burden, antibiotic biofilm concentration by high-performance liquid chromatography or bioassay, and biofilm thickness through scanning electron microscopy. We found a trend toward a significant variation in biofilm methicillin-resistant Staphylococcus aureus burden (log colony-forming unit/mL) among groups (p=.057), and the lowest bacterial burden was found in endotracheal tubes treated with linezolid (1.98±1.68) in comparison with untreated endotracheal tubes (3.72±2.20, p=.045) or those treated with vancomycin (2.97±2.43, p=.286). Biofilm linezolid concentration was 19-fold above the linezolid minimum inhibitory concentration, whereas biofilm vancomycin concentration (1.60±0.91 µg/mL) was consistently below or close to the vancomycin minimum inhibitory concentration. Biofilm was thicker in the vancomycin group (p=.077). Systemic treatment with linezolid limits endotracheal tube biofilm development and methicillin-resistant Staphylococcus aureus burden. The potential clinical usefulness of linezolid in decreasing the risk of biofilm

  2. Detection of bacterial biofilms in different types of chronic otitis media.

    Science.gov (United States)

    Gu, Xingzhi; Keyoumu, Youlidusi; Long, Li; Zhang, Hua

    2014-11-01

    Biofilms are organized bacterial communities that may be homogeneous or heterogeneous. They play a significant role in the pathogenesis of chronic nasal sinusitis, chronic tonsillitis, cholesteatomas, and device-related infections. Despite this, few studies have been done that examine the presence of bacterial biofilms in tissues from patients with different types of COM or middle ear cholesteatomas. In the current study, we examined the presence of biofilms in surgical tissue specimens from humans with chronic ear infections using scanning electron microscopy (SEM). We hypothesize that bacterial biofilms present differently in patients with different types of chronic otitis media. Our results provide new insights regarding treatment of chronic otitis media. A prospective study was conducted in which middle ear tissues were obtained from 38 patients who underwent tympanoplasty and/or tympanomastoid surgery due to chronic ear infections. A total of 50 middle and mastoid tissue samples were processed for SEM analysis. In addition, 38 middle ear secretion specimens were obtained for routine bacterial culture analysis. Bacterial biofilms were present in 85 % (11 of 13) of patients with middle ear cholesteatoma, 92 % (12/13) of patients with chronic otitis suppurative media (CSOM), and 16 % of patients (2/12) with tympanic membrane perforation (TMP). Fungal biofilms were found in two cases of cholesteatoma. The positive coincidence rate between bacterial biofilms visualized by SEM and bacteria detected by culture was 82 %. Our findings suggest that bacterial biofilms are very common in CSOM and middle ear cholesteatomas. Positive bacterial cultures imply the presence of biofilm formation in CSOM and cholesteatomas. As such, our results provide new insights regarding treatment of chronic otitis media.

  3. Subsurface Examination of a Foliar Biofilm Using Scanning Electron- and Focused-Ion-Beam Microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Wallace, Patricia K.; Arey, Bruce W.; Mahaffee, Walt F.

    2011-08-01

    The dual beam scanning electron microscope, equipped with both a focused ion- and scanning electron- beam (FIB SEM) is a novel tool for the exploration of the subsurface structure of biological tissues. The FIB can remove a predetermined amount of material from a selected site to allow for subsurface exploration and when coupled with SEM or scanning ion- beam microscopy (SIM) could be suitable to examine the subsurface structure of bacterial biofilms on the leaf surface. The suitability of chemical and cryofixation was examined for use with the FIB SEM to examine bacterial biofilms on leaf surfaces. The biological control agent, Burkholderia pyroccinia FP62, that rapidly colonizes the leaf surface and forms biofilms, was inoculated onto geranium leaves and incubated in a greenhouse for 7 or 14 days. Cryofixation was not suitable for examination of leaf biofilms because it created a frozen layer over the leaf surface that cracked when exposed to the electron beam and the protective cap required for FIB milling could not be accurately deposited. With chemically fixed samples, it was possible to precisely FIB mill a single cross section (5 µm) or sequential cross sections from a single site without any damage to the surrounding surface. Biofilms, 7 days post-inoculation (DPI), were composed of 2 to 5 bacterial cell layers while biofilms 14 DPI ranged from 5 to greater than 30 cell layers. Empty spaces between bacteria cells in the subsurface structure were observed in biofilms 7- and 14-DPI. Sequential cross sections inferred that the empty spaces were often continuous between FP62 cells and could possibly make up a network of channels throughout the biofilm. FIB SEM was a useful tool to observe the subsurface composition of a foliar biofilm.

  4. Exploiting social evolution in biofilms

    DEFF Research Database (Denmark)

    Boyle, Kerry E; Heilmann, Silja; van Ditmarsch, Dave

    2013-01-01

    and thus, regrettably, select for resistance against their own action. A possible solution lies in targeting the mechanisms by which bacteria interact with each other within biofilms. The emerging field of microbial social evolution combines molecular microbiology with evolutionary theory to dissect...

  5. Candida biofilms: is adhesion sexy?

    Science.gov (United States)

    Soll, David R

    2008-08-26

    The development of Candida albicans biofilms requires two types of adhesion molecule - the Als proteins and Hwp1. Mutational analyses have recently revealed that these molecules play complementary roles, and their characteristics suggest that they may have evolved from primitive mating agglutinins.

  6. Electrochemical impedance spectroscopy of biofilms

    Science.gov (United States)

    Microbial activity that leads to the formation of biofilms on process equipment can accelerate corrosion, reduce heat transfer rates, and generally decrease process efficiencies. Additional concerns arise in the food and pharma industries where product quality and safety are a high priority. Pharmac...

  7. Butyltins in water, biofilm, animals and sediments of the west coast of India

    Digital Repository Service at National Institute of Oceanography (India)

    Bhosle, N.B.; Garg, A.; Jadhav, S.; Harjee, R.; Sawant, S.S.; Venkat, K.; Anil, A.C.

    10 to 513 ng/g in biofilm samples. For the coastal sediment samples the concentration of DBT plus TBT ranged between 36 and 133 ng/g drywt of sediment. For the animal samples the DBT plus TBT ranged between 58 and 825 ng/g drywt of the tissue. Mussel...

  8. Microbial investigations in throat swab and tracheal aspirate specimens are beneficial to predict the corresponding endotracheal tube biofilm flora among intubated neonates with ventilator-associated pneumonia.

    Science.gov (United States)

    Pan, Yun; Du, Lizhong; Ai, Qing; Song, Sijie; Tang, Xiaoli; Zhu, Danping; Yu, Jialin

    2017-08-01

    Ventilator-associated pneumonia (VAP) is a common nosocomial infection in neonatal intensive care units with high morbidity and mortality. Bacterial biofilm in the endotracheal tube (ET) provides a notable and persistent source of pathogens that may cause VAP, and thus is important for VAP detection. However, during intubation microbial investigations in ET, samples are unavailable due to the infeasibility of collecting ET samples during intubation of neonates. It is therefore of great importance to find alternative sources of samples that can help identify the ET biofilm flora. In the present study, the microbial signatures of throat swabs and tracheal aspirates were compared with ET biofilm samples from VAP neonates using 16S ribosomal RNA gene polymerase chain reaction, denaturing gradient gel electrophoresis (DGGE), cloning and sequencing. Sequences were assigned to phylogenetic species using BLAST. Microbial diversity and richness among the three types of specimens were compared based on their DGGE fingerprints, and taxonomic characteristics based on the BLAST results. The microbial richness and diversity of ET biofilms were similar to tracheal aspirate yet significantly different from throat swab samples (P<0.05). Compared with ET biofilms, the overall constituent ratio of microflora was significantly different in throat swab and tracheal aspirate samples (P<0.05). However tracheal aspirate samples were useful for predicting Staphylococcus sp. in ET biofilms with a sensitivity of 85.7% and a specificity of 83.3%. The sensitivity for the combination of tracheal aspirate and throat swab samples to detect Staphylococcus sp. in ET biofilms was 100%. The detection of Pseudomonas sp. in throat swabs assisted its identification in ET biofilms (sensitivity 33.3% and specificity 100%). The results of the present study suggest that microbial investigations in throat swab and tracheal aspirate samples are beneficial for identifying the ET biofilm flora. There may

  9. Hydrodynamic dispersion within porous biofilms

    KAUST Repository

    Davit, Y.

    2013-01-23

    Many microorganisms live within surface-associated consortia, termed biofilms, that can form intricate porous structures interspersed with a network of fluid channels. In such systems, transport phenomena, including flow and advection, regulate various aspects of cell behavior by controlling nutrient supply, evacuation of waste products, and permeation of antimicrobial agents. This study presents multiscale analysis of solute transport in these porous biofilms. We start our analysis with a channel-scale description of mass transport and use the method of volume averaging to derive a set of homogenized equations at the biofilm-scale in the case where the width of the channels is significantly smaller than the thickness of the biofilm. We show that solute transport may be described via two coupled partial differential equations or telegrapher\\'s equations for the averaged concentrations. These models are particularly relevant for chemicals, such as some antimicrobial agents, that penetrate cell clusters very slowly. In most cases, especially for nutrients, solute penetration is faster, and transport can be described via an advection-dispersion equation. In this simpler case, the effective diffusion is characterized by a second-order tensor whose components depend on (1) the topology of the channels\\' network; (2) the solute\\'s diffusion coefficients in the fluid and the cell clusters; (3) hydrodynamic dispersion effects; and (4) an additional dispersion term intrinsic to the two-phase configuration. Although solute transport in biofilms is commonly thought to be diffusion dominated, this analysis shows that hydrodynamic dispersion effects may significantly contribute to transport. © 2013 American Physical Society.

  10. Microbial analysis of in situ biofilm formation in drinking water distribution systems: implications for monitoring and control of drinking water quality.

    Science.gov (United States)

    Douterelo, Isabel; Jackson, M; Solomon, C; Boxall, J

    2016-04-01

    Biofilm formation in drinking water distribution systems (DWDS) is influenced by the source water, the supply infrastructure and the operation of the system. A holistic approach was used to advance knowledge on the development of mixed species biofilms in situ, by using biofilm sampling devices installed in chlorinated networks. Key physico-chemical parameters and conventional microbial indicators for drinking water quality were analysed. Biofilm coverage on pipes was evaluated by scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM). The microbial community structure, bacteria and fungi, of water and biofilms was assessed using pyrosequencing. Conventional wisdom leads to an expectation for less microbial diversity in groundwater supplied systems. However, the analysis of bulk water showed higher microbial diversity in groundwater site samples compared with the surface water site. Conversely, higher diversity and richness were detected in biofilms from the surface water site. The average biofilm coverage was similar among sites. Disinfection residual and other key variables were similar between the two sites, other than nitrates, alkalinity and the hydraulic conditions which were extremely low at the groundwater site. Thus, the unexpected result of an exceptionally low diversity with few dominant genera (Pseudomonas and Basidiobolus) in groundwater biofilm sampl