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Journal of Endodontics Aug 2016The purpose of this study was to combine multiple displacement amplification and checkerboard DNA-DNA hybridization to qualitatively and quantitatively evaluate the...
INTRODUCTION
The purpose of this study was to combine multiple displacement amplification and checkerboard DNA-DNA hybridization to qualitatively and quantitatively evaluate the microbiota present in infections refractory to endodontic treatment.
METHODS
The subjects of this study were 40 patients presenting with periapical lesions refractory to endodontic treatment. Samples were taken by scraping or filing root canal walls with a #10 K-type hand file. Sample DNA was amplified by multiple displacement amplification, and the levels of 107 bacterial taxa were analyzed by checkerboard DNA-DNA hybridization. The taxa were divided into 3 distinct microbial populations depending on their mean proportion in samples (% DNA probe counts ± standard error of the mean) as follows: dominant (≥3.0%), subdominant (>1.6%-3.0%), and residual (≤1.6%) populations. The significance of differences was determined using the Mann-Whitney test.
RESULTS
The taxa present with the highest mean proportions (constituting the dominant population) were Corynebacterium diphtheriae (8.03 ± 0.98), Porphyromonas gingivalis (5.42 ± 2.09), Streptococcus sobrinus (5.33 ± 0.69), and Stenotrophomonas maltophilia (4.72 ± 1.73). Among the subdominant population were Eubacterium saphenum (3.85 ± 1.06), Helicobacter pylori (3.16 ± 0.62), Dialister pneumosintes (3.12 ± 1.1), Clostridium difficile (2.74 ± 0.41), Enterobacter agglomerans (2.64 ± 0.54), Salmonella enterica (2.51 ± 0.52), Mobiluncus mulieris (2.44 ± 0.6), and Klebsiella oxytoca (2.32 ± 0.66). In the population of bacteria present at the lowest mean proportions (the residual population), Bacteroides ureolyticus (0.04 ± 0.01), Haemophilus influenzae (0.04 ± 0.02), and Prevotella oris (0.01 ± 0.01) were found at the lowest mean proportions. Enterococcus faecalis was detected in the residual population (0.52 ± 0.26).
CONCLUSIONS
The microbial climax community in teeth refractory to endodontic treatment not only harbors medically important species but also contains distinct microbial consortia present with different population levels.
Topics: Bacteria; DNA Probes; DNA, Bacterial; Dental Pulp Cavity; Dental Pulp Necrosis; Humans; Microbiota; Nucleic Acid Hybridization; Periapical Diseases; Root Canal Therapy
PubMed: 27377440
DOI: 10.1016/j.joen.2016.05.014 -
Archives of Oral Biology Jan 2010To assess the prevalence of oral colonisation by bacterial respiratory pathogens in hospitalised patients.
OBJECTIVE
To assess the prevalence of oral colonisation by bacterial respiratory pathogens in hospitalised patients.
METHODS
Thirty patients undergoing myocardium revascularisation surgery were evaluated. At baseline (pre-operative phase), full-mouth clinical periodontal assessment was performed. Saliva and biofilm samples were obtained from subjects at baseline and at the post-operative phase, after orotracheal extubation. DNA was extracted from samples and species of Acinetobacter, Pseudomonas, Staphylococcus aureus and Dialister pneumosintes were detected by PCR or culture (for staphylococci isolates).
RESULTS
Most of the subjects were males, with history of hypertension and smoking. Thirteen were edentulous (ED) and 17 were dentate (DE), with moderate chronic periodontitis. The most prevalent bacteria in saliva were Staphylococcus spp. (85.7%), Pseudomonas spp. (83.8%), and Acinetobacter spp. (53.3%). There was a trend for D. pneumosintes to be more frequently detected in DE (43.7%) than ED (11.5%) patients. In plaque samples, DE with >14 teeth showed a higher prevalence of Pseudomonas spp. (100%) than individuals with < or =14 teeth (69.1%; p=0.048). Conversely, P. aeruginosa was more prevalent in subjects with fewer teeth (35.5%) than with >14 teeth (5.7%; p=0.037). All staphylococci isolates were coagulase-negative, and about 11% were positive for the mecA gene. These mecA-positive isolates showed a tendency to increase in all samples, whereas P. aeruginosa reduced after surgery. A strong correlation between the presence of Acinetobacter spp. and Pseudomonas spp. was observed (rho=0.886, p<0.05).
CONCLUSIONS
The oral cavity of hospitalised patients harbours high frequencies of bacterial respiratory pathogens, supporting its potential role as a reservoir for these species.
Topics: Acinetobacter; Biofilms; Chi-Square Distribution; Coronary Disease; Cross Infection; Dental Plaque; Female; Humans; Inpatients; Male; Middle Aged; Mouth; Periodontitis; Polymerase Chain Reaction; Prevalence; Pseudomonas; Saliva; Staphylococcus; Statistics, Nonparametric
PubMed: 19939349
DOI: 10.1016/j.archoralbio.2009.10.005 -
Journal of Applied Oral Science :... 2023Based on a holistic concept of polymicrobial etiology, we have hypothesized that putative and candidate periodontal pathogens are more frequently detected in consortia...
BACKGROUND
Based on a holistic concept of polymicrobial etiology, we have hypothesized that putative and candidate periodontal pathogens are more frequently detected in consortia than alone in advanced forms of periodontal diseases (PD).
OBJECTIVE
To correlate specific consortia of periodontal pathogens with clinical periodontal status and severity of periodontitis.
METHODOLOGY
Subgingival biofilm was obtained from individuals with periodontal health (113, PH), gingivitis (91, G), and periodontitis (209, P). Genomic DNA was purified and the species Aggregatibacter actinomycetemcomitans (Aa), Aa JP2-like strain, Porphyromonas gingivalis (Pg), Dialister pneumosintes (Dp), and Filifactor alocis (Fa) were detected by PCR. Configural frequency and logistic regression analyses were performed to correlate microbial consortia and PD.
RESULTS
Aa + Pg in the presence of Dp (phi=0.240; χ2=11.9, p<0.01), as well as Aa JP2 + Dp + Fa (phi=0.186, χ2=4.6, p<0.05) were significantly more associated in advanced stages of P. The consortium Aa + Fa + Dp was strongly associated with deep pocketing and inflammation (p<0.001). The best predictors of disease severity (80% accuracy) included older age (OR 1.11 [95% CI 1.07 - 1.15], p<0.001), Black/African-American ancestry (OR 1.89 [95% CI 1.19 - 2.99], p=0.007), and high frequency of Aa + Pg + Dp (OR 3.04 [95% CI 1.49 - 6.22], p=0.002).
CONCLUSION
Specific microbial consortia of putative and novel periodontal pathogens, associated with demographic parameters, correlate with severe periodontitis, supporting the multifactorial nature of PD.
Topics: Humans; Periodontal Diseases; Periodontitis; Porphyromonas gingivalis; Bacteroides; Aggregatibacter actinomycetemcomitans; Patient Acuity
PubMed: 36629716
DOI: 10.1590/1678-7757-2022-0359 -
Journal of Clinical Microbiology May 2007Trauma intensive care unit (TICU) patients requiring mechanical respiratory support frequently develop ventilator-associated pneumonia (VAP). Oral and oropharyngeal...
Trauma intensive care unit (TICU) patients requiring mechanical respiratory support frequently develop ventilator-associated pneumonia (VAP). Oral and oropharyngeal bacteria are believed to be responsible for many cases of VAP, but definitive evidence of this relationship is lacking. Earlier studies used conventional culture-based methods for identification of bacterial pathogens, but these methods are insufficient, as some bacteria may be uncultivable or difficult to grow. The purpose of this study was to use a culture-independent molecular approach to analyze and compare the bacterial species colonizing the oral cavity and the lungs of TICU patients who developed VAP. Bacterial samples were acquired from the dorsal tongue and bronchoalveolar lavage fluid of 16 patients. Bacterial DNA was extracted, and the 16S rRNA genes were PCR amplified, cloned into Escherichia coli, and sequenced. The sequencing data revealed the following: (i) a wide diversity of bacterial species in both the oral and pulmonary sites, some of them novel; (ii) known and putative respiratory pathogens colonizing both the oral cavity and lungs of 14 patients; and (iii) a number of bacterial pathogens (e.g., Dialister pneumosintes, Haemophilus segnis, Gemella morbillorum, and Pseudomonas fluorescens) in lung samples that had not been reported previously at this site when culture-based methods were used. Our data indicate that the dorsal surface of the tongue serves as a potential reservoir for bacterial species involved in VAP. Furthermore, it is clear that the diversity of bacterial pathogens for VAP is far more complex than the current literature suggests.
Topics: Adult; Bacteria; Female; Humans; Male; Middle Aged; Mouth; Phylogeny; Pneumonia, Bacterial; Pneumonia, Ventilator-Associated; Respiratory System; Species Specificity; Wounds and Injuries
PubMed: 17301280
DOI: 10.1128/JCM.01963-06 -
Frontiers in Cellular and Infection... 2015Patients with acquired immunodeficiency syndrome (AIDS) are at high risk of opportunistic infections. Oral manifestations have been associated with the level of...
Patients with acquired immunodeficiency syndrome (AIDS) are at high risk of opportunistic infections. Oral manifestations have been associated with the level of immunosuppression, these include periodontal diseases, and understanding the microbial populations in the oral cavity is crucial for clinical management. The aim of this study was to examine the salivary bacterial diversity in patients newly admitted to the AIDS ward of the Public Health Clinical Center (China). Saliva samples were collected from 15 patients with AIDS who were randomly recruited between December 2013 and March 2014. Extracted DNA was used as template to amplify bacterial 16S rRNA. Sequencing of the amplicon library was performed using a 454 GS-FLX Titanium sequencing platform. Reads were optimized and clustered into operational taxonomic units for further analysis. A total of 10 bacterial phyla (106 genera) were detected. Firmicutes, Bacteroidetes, and Proteobacteria were preponderant in the salivary microbiota in AIDS patients. The pathogen, Capnocytophaga sp., and others not considered pathogenic such as Neisseria elongata, Streptococcus mitis, and Mycoplasma salivarium but which may be opportunistic infective agents were detected. Dialister pneumosintes, Eubacterium infirmum, Rothia mucilaginosa, and Treponema parvum were preponderant in AIDS patients with periodontitis. Patients with necrotic periodontitis had a distinct salivary bacterial profile from those with chronic periodontitis. This is the first study using advanced sequencing techniques focused on hospitalized AIDS patients showing the diversity of their salivary microbiota.
Topics: Acquired Immunodeficiency Syndrome; Adult; Bacteria; Biota; China; Cluster Analysis; DNA, Bacterial; DNA, Ribosomal; Female; Gingivitis; Humans; Male; Middle Aged; Periodontal Diseases; Phylogeny; RNA, Ribosomal, 16S; Saliva; Sequence Analysis, DNA
PubMed: 26191508
DOI: 10.3389/fcimb.2015.00055