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Journal of Periodontology Oct 2017The microbiota colonizing dental implants has been said to be similar to the microbiome surrounding teeth. In the absence of inflammation, a biofilm with pathologic...
BACKGROUND
The microbiota colonizing dental implants has been said to be similar to the microbiome surrounding teeth. In the absence of inflammation, a biofilm with pathologic bacteria can cover implant surfaces exposed to the oral cavity, for example, due to a remodeling process. The aim of the present study is to identify microbiota surrounding exposed dental implants in patients with and without a history of periodontitis through a deep-sequencing approach.
METHODS
An experimental abutment with the same surface and structure as a commercially available dental implant was used. Bacterial DNA was isolated, and the 16S ribosomal RNA gene was amplified and sequenced. Multiplexed tag-encoded sequencing of DNA from the samples was performed, and the reads were processed by metagenomic rapid annotation.
RESULTS
A wide variety of bacteria, 96 species, were identified. The most frequently found bacteria were Fusobacterium nucleatum and Prevotella denticola. Some species generally associated with periodontitis were found to a greater extent in patients without a history of periodontitis. Some bacteria that have never been described as part of the oral microbiome were identified in the present sample.
CONCLUSIONS
Analysis of data suggests that the bacteria surrounding exposed dental implants form a diverse microbiome regardless of the periodontal profile of patients. Further research is needed to clarify the role of these microorganisms in the oral environment.
Topics: Aged; Aged, 80 and over; Bacteria; Biofilms; DNA, Bacterial; Dental Abutments; Dental Implants; Female; Humans; Implants, Experimental; Male; Microbiota; Middle Aged; Periodontitis; RNA, Ribosomal, 16S
PubMed: 28492362
DOI: 10.1902/jop.2017.170051 -
Journal of Dental Sciences Dec 2019
PubMed: 31890133
DOI: 10.1016/j.jds.2019.04.006 -
Scientific Reports Apr 2020To construct a saliva-based caries risk assessment model, saliva samples from 176 severe early childhood caries (S-ECC) children and 178 healthy (H) children were...
To construct a saliva-based caries risk assessment model, saliva samples from 176 severe early childhood caries (S-ECC) children and 178 healthy (H) children were screened by real-time PCR-based quantification of the selected species, including Streptococcus mutans, Prevotella pallens, Prevotella denticola and Lactobacillus fermentum. Host factors including caries status, dmft indices, age, gender, and geographic origin were assessed in their influence on abundance of the targeted species, which revealed host caries status as the dominant factor, followed by dmft indices (both P < 0.01). Moreover, levels of S. mutans and P. denticola in the S-ECC group were significantly higher than those in the healthy group (P < 0.001 for S. mutans and P < 0.01 for P. denticola). Interestingly, the co-occurrence network of these targeted species in the S-ECC group differed from that from the healthy group. Finally, based on the combined change pattern of S. mutans and P. pallens, we constructed an S-ECC diagnosis model with an accuracy of 72%. This saliva-based caries diagnosis model is of potential value for circumstances where sampling dental plague is difficult.
Topics: Child; Child, Preschool; Dental Caries; Female; Humans; Limosilactobacillus fermentum; Male; Microbiota; Prevotella; Saliva; Streptococcus mutans
PubMed: 32286402
DOI: 10.1038/s41598-020-63222-1 -
Annals of the Rheumatic Diseases Jan 2020The causality and pathogenic mechanism of microbiome composition remain elusive in many diseases, including autoimmune diseases such as rheumatoid arthritis (RA). This...
OBJECTIVE
The causality and pathogenic mechanism of microbiome composition remain elusive in many diseases, including autoimmune diseases such as rheumatoid arthritis (RA). This study aimed to elucidate gut microbiome's role in RA pathology by a comprehensive metagenome-wide association study (MWAS).
METHODS
We conducted MWAS of the RA gut microbiome in the Japanese population (=82, =42) by using whole-genome shotgun sequencing of high depth (average 13 Gb per sample). Our MWAS consisted of three major bioinformatic analytic pipelines (phylogenetic analysis, functional gene analysis and pathway analysis).
RESULTS
Phylogenetic case-control association tests showed high abundance of multiple species belonging to the genus (e.g., ) in the RA case metagenome. The non-linear machine learning method efficiently deconvoluted the case-control phylogenetic discrepancy. Gene functional assessments showed that the abundance of one redox reaction-related gene (R6FCZ7) was significantly decreased in the RA metagenome compared with controls. A variety of biological pathways including those related to metabolism (e.g., fatty acid biosynthesis and glycosaminoglycan degradation) were enriched in the case-control comparison. A population-specific link between the metagenome and host genome was identified by comparing biological pathway enrichment between the RA metagenome and the RA genome-wide association study results. No apparent discrepancy in alpha or beta diversities of metagenome was found between RA cases and controls.
CONCLUSION
Our shotgun sequencing-based MWAS highlights a novel link among the gut microbiome, host genome and pathology of RA, which contributes to our understanding of the microbiome's role in RA aetiology.
Topics: Arthritis, Rheumatoid; Bacteroides; Case-Control Studies; Fatty Acids; Female; Gastrointestinal Microbiome; Genome-Wide Association Study; Humans; Japan; Male; Metabolic Networks and Pathways; Metagenome; Metagenomics; Middle Aged; Oxidation-Reduction; Phylogeny; Prevotella; Whole Genome Sequencing
PubMed: 31699813
DOI: 10.1136/annrheumdis-2019-215743 -
Scientific Reports Jan 2021Smoking is a risk factor for periodontal disease, and a cause of oral microbiome dysbiosis. While this has been evaluated for traditional cigarette smoking, there is...
Smoking is a risk factor for periodontal disease, and a cause of oral microbiome dysbiosis. While this has been evaluated for traditional cigarette smoking, there is limited research on the effect of other tobacco types on the oral microbiome. This study investigates subgingival microbiome composition in smokers of different tobacco types and their effect on periodontal health. Subgingival plaques were collected from 40 individuals, including smokers of either cigarettes, medwakh, or shisha, and non-smokers seeking dental treatment at the University Dental Hospital in Sharjah, United Arab Emirates. The entire (~ 1500 bp) 16S rRNA bacterial gene was fully amplified and sequenced using Oxford Nanopore technology. Subjects were compared for the relative abundance and diversity of subgingival microbiota, considering smoking and periodontal condition. The relative abundances of several pathogens were significantly higher among smokers, such as Prevotella denticola and Treponema sp. OMZ 838 in medwakh smokers, Streptococcus mutans and Veillonella dispar in cigarette smokers, Streptococcus sanguinis and Tannerella forsythia in shisha smokers. Subgingival microbiome of smokers was altered even in subjects with no or mild periodontitis, probably making them more prone to severe periodontal diseases. Microbiome profiling can be a useful tool for periodontal risk assessment. Further studies are recommended to investigate the impact of tobacco cessation on periodontal disease progression and oral microbiome.
Topics: Adolescent; Adult; Bacteria; Cigarette Smoking; Dental Plaque; Female; Gingiva; Humans; Male; Microbiota; Middle Aged; Periodontitis; Periodontium; Pilot Projects; RNA, Ribosomal, 16S; Tobacco Smoking; United Arab Emirates; Young Adult
PubMed: 33441919
DOI: 10.1038/s41598-020-80937-3 -
Revista Espanola de Quimioterapia :... Mar 2007Resistance in streptococci or Gram-negative bacteria is associated with antibiotic consumption. Scarce information exists on the antibiotic susceptibility of bacterial...
Resistance in streptococci or Gram-negative bacteria is associated with antibiotic consumption. Scarce information exists on the antibiotic susceptibility of bacterial isolates from patients with periodontitis in countries with high antibiotic consumption, as this is an area in which microbiological testing is not performed in daily practice. The present study was undertaken to explore the susceptibility of bacterial isolates in periodontitis to antibiotics prescribed in odontology in Spain as treatment for local infections or prophylaxis for distant focal infections. Periodontal samples were prospectively collected in 48 patients classified by pocket depth of <4 mm and >or=4 mm. Species were identified by culture, selecting the five most frequent morphotypes per sample, and polymerase chain reaction (PCR). Susceptibility was determined by E-test. A total of 261 isolates were identified: 72.9% patients had Streptococcus oralis; 70.8% Streptococcus mitis; 60.4% Prevotella buccae; 39.6% Prevotella denticola; 37.5% Fusobacterium nucleatum; 35.4% Prevotella intermedia; 25% Capnocytophaga spp.; 23% Veillonella spp.; 22.9% Prevotella melaninogenica and Streptococcus sanguis; and <20% other species. Streptococcus viridans resistance rates were 0% for amoxicillin, approximately 10% for clindamycin, 9-22% for tetracycline, and for azithromycin ranged from 18.2% for S. sanguis to 47.7% for S. mitis. Prevotella isolates were susceptible to amoxicillin-clavulanic acid, with amoxicillin resistance ranging from 17.1% in P. buccae to 26.3% in P. denticola. Metronidazole resistance was <6% in all Prevotella species, while clindamycin resistance ranged from 0 to 21.1%. beta-Lactamase production was positive in 54.1% Prevotella spp., 38.9% F. nucleatum, 30% Capnocytophaga spp., and 10% Veillonella spp. In this study, amoxicillin-clavulanic acid was the most active antibiotic against all species tested, followed by metronidazole in the case of anaerobes.
Topics: Adult; Aged; Anti-Bacterial Agents; Bacteria; Drug Resistance, Bacterial; Drug Utilization; Female; Humans; Male; Microbial Sensitivity Tests; Middle Aged; Periodontal Diseases; Reverse Transcriptase Polymerase Chain Reaction; Spain; Streptococcus; beta-Lactamases
PubMed: 17530037
DOI: No ID Found -
Infection and Immunity Jul 1993The classical twin model was utilized in this study in an attempt to determine the importance of host genetics to the composition of the subgingival flora.... (Comparative Study)
Comparative Study
The classical twin model was utilized in this study in an attempt to determine the importance of host genetics to the composition of the subgingival flora. Simultaneously, the effect of puberty on the flora composition was assessed. The compositions of the floras were significantly different at ages 11 and 14 in the same people, indicating that transition to an adult flora composition may be initiated during puberty. However, the numbers of subjects who had prepubertal and postpubertal testosterone levels in this study were too small to demonstrate significant differences based solely on testosterone level (P = 0.053 and 0.11 for tests of unrelated members, i.e., all twins "a," the first twin of each pair, and all twins "b," the second twin of each pair). Sixteen unrelated 11-year-old subjects had prepubertal levels of less than 30 ng of testosterone per dl of serum, and only six of these unrelated subjects had levels above 300 ng/dl by age 14. Of their twin siblings, who formed the second group of unrelated individuals, 15 had prepubertal levels and only 5 reached postpubertal levels. Unpaired t tests indicated that Veillonella atypica, Prevotella denticola, and Prevotella melaninogenica were among the species that contributed most to changes in flora composition during puberty. The compositions of subgingival floras of 11-year-old monozygous and dizygous male twins were significantly more similar than those of unrelated subjects in the study (P = 0.004 and 0.009, respectively). At 12.5 years of age, the floras of monozygous twins remained more similar than those of unrelated subjects (P = 0.001), but the dizygous-twin floras were not significantly more similar than those of unrelated people. This difference corresponded with moderate and varied testosterone levels within dizygous-twin pairs at age 12.5. By age 14 both monozygous and dizygous twins again had floras with compositions more similar than those of unrelated people (P = 0.008 and 0.002, respectively). Estimates of the genetic contributions to the increased similarity of the floras of twins as compared with floras of unrelated people indicated that the concentrations of several species in the flora may be influenced by host genetic factors. The prevalence of certain other species appeared to be controlled primarily by environment.
Topics: Adolescent; Adult; Bacteria; Child; Environment; Gingiva; Humans; Male; Puberty; Testosterone; Twins, Dizygotic; Twins, Monozygotic
PubMed: 8514392
DOI: 10.1128/iai.61.7.2891-2898.1993 -
Clinical Microbiology and Infection :... Jun 1999OBJECTIVE: To evaluate the Rapid ID 32A system (bioMérieux, Marcy-l'Etoile, France) for the identification of anaerobic Gram-negative bacilli, excluding the Bacteroides...
OBJECTIVE: To evaluate the Rapid ID 32A system (bioMérieux, Marcy-l'Etoile, France) for the identification of anaerobic Gram-negative bacilli, excluding the Bacteroides fragilis group. METHODS: Five hundred and twenty-eight identified clinical isolates of non-B. fragilis group anaerobic Gram-negative bacilli were tested in the Rapid ID 32A system, and identifications were compared with those obtained with conventional biochemical tests and gas-liquid chromatography. RESULTS: The Rapid ID 32A system correctly identified 280 (60.9%) of the 460 isolates tested for which taxa were included in the database, without the need for additional testing. A further 97 (21.1%) isolates were correctly identified to species level following the performance of complementary tests recommended by the manufacturer. Fifty-nine (12.8%) isolates were identified at the genus level only, and 21 (4.6%) were misidentified at the species level. Three isolates of Prevotella were not identified by the system. Of the 68 isolates belonging to taxa not included in the database, no identification was obtained for 33 (48.5%), while 35 (51.5%) were misidentified. CONCLUSIONS: The Rapid ID 32A system provided a rapid and reliable method for the identification of non-B. fragilis group, anaerobic Gram-negative bacilli to the genus level, while the success of species-level identification varied with different taxa. There was poor discrimination between Fusobacterium nucleatum and F. necrophorum, between Porphyromonas asaccharolytica and Porphyromonas endodontalis, and between Prevotella buccalis, Prevotella denticola, Prevotella loescheii, Prevotella melaninogenica and Prevotella oralis. The need to perform conventional complementary tests on 149 (32.4%) of the 460 isolates compromised the usefulness of the system for rapid species identification.
PubMed: 11856276
DOI: 10.1111/j.1469-0691.1999.tb00150.x -
PloS One 2014Immunological processes in the etiopathogenesis of periodontitis, especially the aggressive form, are not well understood. This study examined clinical as well as...
OBJECTIVE
Immunological processes in the etiopathogenesis of periodontitis, especially the aggressive form, are not well understood. This study examined clinical as well as systemic immunological and local microbiological features in healthy controls and patients with different forms of periodontitis.
MATERIALS AND METHODS
14 healthy subjects, 15 patients diagnosed with aggressive periodontitis, and 11 patients with chronic periodontitis were recruited. Periodontal examination was performed and peripheral blood was collected from each patient. Lymphocyte populations as well as the release of cytokines by T-helper cells were determined by flow cytometry and enzyme linked immunosorbent spot assay. Subgingival plaque samples were taken from each individual and immediately cultivated for microbiological examination.
RESULTS
When stimulating peripheral blood mononuclear cells (PBMCs) with lipopolysaccharide, a higher IL-1β release was found in patients with moderate chronic periodontitis compared to the other groups (p<0.01). Numbers of B-cells, naïve and transitional B-cells, memory B-cells, and switched memory B-cells were within the reference range for all groups, but patients with chronic periodontitis showed the highest percentage of memory B-cells without class switch (p = 0.01). The subgingival plaque differed quantitatively as well as qualitatively with a higher number of Gram-negative anaerobic species in periodontitis patients. Prevotella denticola was found more often in patients with aggressive periodontitis (p<0.001) but did not show an association to any of the systemic immunological findings. Porphyromonas gingivalis, which was only found in patients with moderate chronic periodontitis, seems to be associated with an activation of the systemic immune response.
CONCLUSION
Differences between aggressive periodontitis and moderate chronic periodontitis are evident, which raises the question of an inadequate balance between systemic immune response and bacterial infection in aggressive periodontitis.
Topics: Adult; B-Lymphocytes; Bacteroidaceae Infections; Case-Control Studies; Chronic Periodontitis; Female; Humans; Interleukin-1beta; Male; Middle Aged; Porphyromonas gingivalis; Precursor Cells, B-Lymphoid; Prevotella; T-Lymphocytes, Helper-Inducer; Young Adult
PubMed: 25299619
DOI: 10.1371/journal.pone.0109187 -
Frontiers in Medicine 2021Brain abscesses are associated with an increased long-term risk of new seizures and increased mortality within several years after infection. Common microorganisms that...
Brain abscesses are associated with an increased long-term risk of new seizures and increased mortality within several years after infection. Common microorganisms that cause brain abscesses include bacteria, fungi, and mycoplasma. We report a 75-year-old man with a brain abscess caused by , an oral pathogen. Based on the clinical condition, we suspected that the patient had a blood-borne brain abscess, and he received antibiotics and systemic supportive treatment. The patient developed shock for the second time after negative Gram-staining results. Metagenomics next-generation sequencing showed one strain from the oral microbiome, confirming our hypothesis, and targeted antibiotic treatment was administered quickly. Thus, we report a case in which genomic analysis was the critical factor in determining the best antimicrobial therapy for administration.
PubMed: 33693022
DOI: 10.3389/fmed.2021.644130