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Microorganisms May 2020Oral bacteria possess the ability to form biofilms on solid surfaces. After the penetration of oral bacteria into the pulp, the contact between biofilms and pulp tissue...
Oral bacteria possess the ability to form biofilms on solid surfaces. After the penetration of oral bacteria into the pulp, the contact between biofilms and pulp tissue may result in pulpitis, pulp necrosis and/or periapical lesion. Depending on the environmental conditions and the availability of nutrients in the pulp chamber and root canals, mainly Gram-negative anaerobic microorganisms predominate and form the intracanal endodontic biofilm. The objective of the present study was to investigate the role of different substrates on biofilm formation as well as the separate and collective incorporation of six endodontic pathogens, namely and into a nine-species "basic biofilm". This biofilm was formed in vitro as a standard subgingival biofilm, comprising and The resulting endodontic-like biofilms were grown 64 h under the same conditions on hydroxyapatite and dentin discs. After harvesting the endodontic-like biofilms, the bacterial growth was determined using quantitative real-time PCR, were labeled using fluorescence in situ hybridization (FISH) and analyzed by confocal laser scanning microscopy (CLSM). The addition of six endodontic pathogens to the "basic biofilm" induced a decrease in the cell number of the "basic" species. Interestingly, counts increased in biofilms containing and respectively, both on hydroxyapatite and on dentin discs, whereas counts increased only on dentin discs by addition of . The growth of on hydroxyapatite discs and of and on dentin discs were significantly higher in the biofilm containing all species than in the "basic biofilm". Contrarily, the counts of , and on hydroxyapatite discs as well as counts of and on dentin discs decreased in the all-species biofilm. Overall, all bacterial species associated with endodontic infections were successfully incorporated into the standard multispecies biofilm model both on hydroxyapatite and dentin discs. Thus, future investigations on endodontic infections can rely on this newly established endodontic-like multispecies biofilm model.
PubMed: 32384777
DOI: 10.3390/microorganisms8050674 -
International Dental Journal Mar 2024Psychological stress can be a common risk factor for the development of oral and systemic disease; therefore, analysis of a pathophysiologic mechanisms that may explain...
OBJECTIVE
Psychological stress can be a common risk factor for the development of oral and systemic disease; therefore, analysis of a pathophysiologic mechanisms that may explain this association may be significant in planning preventive strategies. The aim of this study was to investigate the association amongst academic stress, periodontal health, and salivary cortisol and nitrite and nitrate levels in a sample of university students.
METHODS
Participants (N = 14) were classified into 2 groups according to their exposure to academic stress due to periods of university exams (n = 6 and n = 8, respectively). All participants were subjected evlauted for their behavioural, psychological, and anthropometric parameters, as well as an oral health examination. A real-time polymerase chain reaction analysis in samples of saliva and plaque was used to detect Prevotella intermedia and Veillonella dispar as well as the total bacterial count. Nitrite/nitrate ratio (NR ratio) and cortisol in saliva were evaluated by enzyme-linked immunosorbent assay.
RESULTS
Full Mouth Bleeding Score, Full Mouth Plaque Score, and Gingival Index were significantly higher in the group exposed to academic stress. Nitrite was directly related to the presence of V dispar (coefficient, 0.13; P = .00; CI, 0.07 to 0.19) and inversely related to total bacterial count (coefficient, -0.07; P = .012; CI, -0.13 to 0.02). NR ratio was directly related to V dispar (coefficient, 4.35; P = .010; 95% CI, 1.35 to 7.36) and inversely related to total bacterial count (coefficient, -4.05; P = .018; 95% CI, -7.32 to 0.86).
CONCLUSIONS
These results confirm the importance of stress on periodontal health and salivary nitrite concentration and highlight a potential differential role of specific bacteria on nitrite concentration in saliva.
PubMed: 38538383
DOI: 10.1016/j.identj.2024.02.003 -
BMC Microbiology Mar 2024Oral microbiome dysbacteriosis has been reported to be associated with the pathogenesis of advanced esophageal cancer. However, few studies investigated the potential...
BACKGROUND
Oral microbiome dysbacteriosis has been reported to be associated with the pathogenesis of advanced esophageal cancer. However, few studies investigated the potential role of oral and gastric microbiota in early-stage intramucosal esophageal squamous carcinoma (EIESC).
METHOD
A total of 104 samples were collected from 31 patients with EIESC and 21 healthy controls. The compositions of oral and gastric microbiota were analyzed using 16 S rRNA V3-V4 amplicon sequencing. Linear discriminant analysis effect size (LEfSe) analysis was performed to assess taxonomic differences between groups. The correlation between oral microbiota and clinicopathological factors was evaluated using Spearman correlation analysis. Additionally, co-occurrence networks were established and random forest models were utilized to identify significant microbial biomarkers for distinguishing between the EIESC and control groups.
RESULTS
A total of 292 oral genera and 223 species were identified in both EIESC and healthy controls. Six oral genera were remarkably enriched in EIESC groups, including the genera Porphyromonas, Shigella, Subdoligranulum, Leptotrichia, Paludibacter, and Odoribacter. LEfSe analysis identified genera Porphyromonas and Leptotrichia with LDA scores > 3. In the random forest model, Porphyromonas endodontalis ranked the top microbial biomarker to differentiate EIESC from controls. The elimination rate of Porphyromonas endodontalis from the oral cavity to the stomach was also dramatically decreased in the EIESC group than controls. In the microbial co-occurrence network, Porphyromonas endodontalis was positively correlated with Prevotella tannerae and Prevotella intermedia and was negatively correlated with Veillonella dispar.
CONCLUSION
Our study potentially indicates that the dysbacteriosis of both the oral and gastric microbiome was associated with EIESC. Larger scale studies and experimental animal models are urgently needed to confirm the possible role of microbial dysbacteriosis in the pathogenesis of EIESC. (Chinese Clinical Trial Registry Center, ChiCTR2200063464, Registered 07 September 2022, https://www.chictr.org.cn/showproj.html?proj=178563).
Topics: Humans; Gastrointestinal Microbiome; Esophageal Squamous Cell Carcinoma; Esophageal Neoplasms; Dysbiosis; Mouth; Porphyromonas; RNA, Ribosomal, 16S
PubMed: 38491387
DOI: 10.1186/s12866-024-03233-4 -
PloS One 2017Poor oral hygiene often leads to chronic diseases such as periodontitis and dental caries resulting in substantial economic costs and diminished quality of life in not...
Poor oral hygiene often leads to chronic diseases such as periodontitis and dental caries resulting in substantial economic costs and diminished quality of life in not only adults but also in children. In this study, the salivary microbiome was characterized in a group of children stratified by the Simplified Oral Hygiene Index (OHI-S). Illumina MiSeq high-throughput sequencing based on the 16S rRNA was utilized to analyze 90 salivary samples (24 Good, 31 Moderate and 35 Poor oral hygiene) from a cohort of Thai children. A total of 38,521 OTUs (Operational Taxonomic Units) with a 97% similarity were characterized in all of the salivary samples. Twenty taxonomic groups (Seventeen genera, two families and one class; Streptococcus, Veillonella, Gemellaceae, Prevotella, Rothia, Porphyromonas, Granulicatella, Actinomyces, TM-7-3, Leptotrichia, Haemophilus, Selenomonas, Neisseria, Megasphaera, Capnocytophaga, Oribacterium, Abiotrophia, Lachnospiraceae, Peptostreptococcus, and Atopobium) were found in all subjects and constituted 94.5-96.5% of the microbiome. Of these twenty genera, the proportion of Streptococcus decreased while Veillonella increased with poor oral hygiene status (P < 0.05). Furthermore, an unassigned species of Veillonella, Veillonella dispar and Veillonella parvula tended to be elevated in the Poor oral hygiene group. This is the first study demonstrating an important association between increase of Veillonella and poor oral hygiene status in children. However, further studies are required to identify the majority of Veillonella at species level in salivary microbiome of the Poor oral hygiene group.
Topics: Adolescent; Child; Female; Humans; Male; Microbiota; Oral Hygiene Index; RNA, Bacterial; RNA, Ribosomal, 16S; Saliva
PubMed: 28934367
DOI: 10.1371/journal.pone.0185274 -
International Journal of Chronic... 2017The study aimed to determine the relationship between throat microbiome and COPD. Sixty-five Chinese males (n=20, smokers without COPD; n=45 smokers with COPD) were...
The study aimed to determine the relationship between throat microbiome and COPD. Sixty-five Chinese males (n=20, smokers without COPD; n=45 smokers with COPD) were included. Nonmetric multidimensional scaling indicated differences of microbiome between COPD and controls, but no difference was observed between COPD patients with differing degrees of lung function or disease severity. Rarefaction analyses suggested that operational taxonomic units (OTUs, species-level) richness decreased in COPD. The dominant taxa between COPD and controls were similar, but the proportions of taxonomic distribution were different. The dominant phyla were and . The dominant genera were and . Two dominant OTUs, otu3 (_) and otu4 (s_unclassified), were identified. Otu3 and its father-level taxa, which were negatively correlated with predicted percent of forced expiratory volume in a second (FEV%pred), were increased in COPD. By contrast, otu4 and its father-level taxa, which were positively correlated with FEV%pred, were decreased in COPD. Otu4 also showed a slight potential as a COPD biomarker. To conclude, the throat microbiome was different between smokers with or without COPD, which is similar to findings from the lower respiratory tract. This study may strengthen our understanding of the relationship between microbiomes of different airway sites and COPD.
Topics: Aged; Bacteria; Case-Control Studies; China; Cross-Sectional Studies; Forced Expiratory Volume; Humans; Lung; Male; Microbiota; Middle Aged; Pharynx; Pulmonary Disease, Chronic Obstructive; Ribotyping; Severity of Illness Index; Smoking
PubMed: 28740374
DOI: 10.2147/COPD.S140243 -
Cureus Sep 2021We present the case of a 50-year-old man presenting with fever, back pain, persistent bacteremia with , echocardiographic evidence of a tricuspid valve vegetation...
We present the case of a 50-year-old man presenting with fever, back pain, persistent bacteremia with , echocardiographic evidence of a tricuspid valve vegetation increasing in size, and magnetic resonance imaging suggesting new vertebral osteomyelitis. He was successfully treated with intravenous ceftriaxone for six weeks. Deep-seated infections secondary to species are rare, but cases of endocarditis, osteomyelitis, and meningitis have been reported in the literature. Given species are normal human commensals present in the oropharyngeal flora, we suspect our patient developed native tricuspid valve endocarditis and vertebral osteomyelitis as a complication of either poor dentition or contaminated injection drug use paraphernalia and subsequent hematogenous seeding.
PubMed: 34667667
DOI: 10.7759/cureus.17989 -
Applied and Environmental Microbiology Jul 2014Indigenous oral bacteria in the tongue coating such as Veillonella have been identified as the main producers of hydrogen sulfide (H2S), one of the major components of...
Indigenous oral bacteria in the tongue coating such as Veillonella have been identified as the main producers of hydrogen sulfide (H2S), one of the major components of oral malodor. However, there is little information on the physiological properties of H2S production by oral Veillonella such as metabolic activity and oral environmental factors which may affect H2S production. Thus, in the present study, the H2S-producing activity of growing cells, resting cells, and cell extracts of oral Veillonella species and the effects of oral environmental factors, including pH and lactate, were investigated. Type strains of Veillonella atypica, Veillonella dispar, and Veillonella parvula were used. These Veillonella species produced H2S during growth in the presence of l-cysteine. Resting cells of these bacteria produced H2S from l-cysteine, and the cell extracts showed enzymatic activity to convert l-cysteine to H2S. H2S production by resting cells was higher at pH 6 to 7 and lower at pH 5. The presence of lactate markedly increased H2S production by resting cells (4.5- to 23.7-fold), while lactate had no effect on enzymatic activity in cell extracts. In addition to H2S, ammonia was produced in cell extracts of all the strains, indicating that H2S was produced by the catalysis of cystathionine γ-lyase (EC 4.4.1.1). Serine was also produced in cell extracts of V. atypica and V. parvula, suggesting the involvement of cystathionine β-synthase lyase (EC 4.2.1.22) in these strains. This study indicates that Veillonella produce H2S from l-cysteine and that their H2S production can be regulated by oral environmental factors, namely, pH and lactate.
Topics: Alanine; Ammonia; Cystathionine beta-Synthase; Cystathionine gamma-Lyase; Cysteine; Hydrogen Sulfide; Hydrogen-Ion Concentration; Lactic Acid; Serine; Sulfides; Veillonella
PubMed: 24795374
DOI: 10.1128/AEM.00606-14 -
NPJ Biofilms and Microbiomes Mar 2020Cigarette smoking affects the oral microbiome, which is related to various systemic diseases. While studies that investigated the relationship between smoking and the...
Cigarette smoking affects the oral microbiome, which is related to various systemic diseases. While studies that investigated the relationship between smoking and the oral microbiome by 16S rRNA amplicon sequencing have been performed, investigations involving metagenomic sequences are rare. We investigated the bacterial species composition in the tongue microbiome, as well as single-nucleotide variant (SNV) profiles and gene content of these species, in never and current smokers by utilizing metagenomic sequences. Among 234 never smokers and 52 current smokers, beta diversity, as assessed by weighted UniFrac measure, differed between never and current smokers (pseudo-F = 8.44, R = 0.028, p = 0.001). Among the 26 species that had sufficient coverage, the SNV profiles of Actinomyces graevenitzii, Megasphaera micronuciformis, Rothia mucilaginosa, Veillonella dispar, and one Veillonella sp. were significantly different between never and current smokers. Analysis of gene and pathway content revealed that genes related to the lipopolysaccharide biosynthesis pathway in Veillonella dispar were present more frequently in current smokers. We found that species-level tongue microbiome differed between never and current smokers, and 5 species from never and current smokers likely harbor different strains, as suggested by the difference in SNV frequency.
Topics: Adult; Aged; Bacteria; Case-Control Studies; Cigarette Smoking; DNA, Bacterial; DNA, Ribosomal; Female; High-Throughput Nucleotide Sequencing; Humans; Male; Metagenomics; Middle Aged; Phylogeny; Polymorphism, Single Nucleotide; RNA, Ribosomal, 16S; Sequence Analysis, DNA; Tongue
PubMed: 32170059
DOI: 10.1038/s41522-020-0121-6 -
Journal of Gastrointestinal Surgery :... Aug 2020Recently, the link between obesity and gut microbiota has become a focus for research. This study shed some light on the modification of postoperative gut microbial...
BACKGROUND
Recently, the link between obesity and gut microbiota has become a focus for research. This study shed some light on the modification of postoperative gut microbial composition after bariatric surgery.
METHODS
A prospective longitudinal study on healthy lean subjects and patients who underwent bariatric surgery (Roux-en-Y gastric bypass and laparoscopic sleeve gastrectomy) was carried out. Anthropometric and metabolic data, smoking, food preferences data, and stool samples were collected from lean subjects and from obese patients before and 3 and 6 months after surgery (T0, T3, and T6, respectively).
RESULTS
We collected stool samples from 25 obese patients before surgery and 3 and 6 months thereafter and from 25 normal weight patients. After Roux-en-Y gastric bypass, Yokenella regensburgei (p < 0.05), Fusobacterium varium (p < 0.05), Veillonella dispar/atypica (p < 0.05), and Streptococcus australis/gordonii (p < 0.05) were transiently identified in the gut at T3. Roux-en-Y gastric bypass patients had a permanent increase in Akkermansia muciniphila (p < 0.05), which is associated with healthy metabolism, both at T3 and T6. There were no significant changes in gut microbiota in laparoscopic sleeve gastrectomy patients.
CONCLUSIONS
In our study, Roux-en-Y gastric bypass induced major microbial differences and greater weight loss compared with laparoscopic sleeve gastrectomy. Analyzing the microbiota composition, a proliferation of potential pathogens and the onset of beneficial bacteria was observed. The effects of these bacteria on human health are still far from clear. Understanding the mechanisms of action of these bacteria could be the keystone in developing new therapeutic strategies for obesity.
Topics: Bariatric Surgery; Enterobacteriaceae; Fusobacterium; Gastrectomy; Gastric Bypass; Gastrointestinal Microbiome; Humans; Laparoscopy; Longitudinal Studies; Obesity, Morbid; Prospective Studies; Streptococcus; Veillonella
PubMed: 31388884
DOI: 10.1007/s11605-019-04321-x -
Frontiers in Microbiology 2022This study analyzed the antimicrobial and antibiofilm action and cytotoxicity of extract (HEScL) and silver nanoparticles (AgNPs-HEScL) from leaves. GC-MS, UV-Vis, EDX,...
This study analyzed the antimicrobial and antibiofilm action and cytotoxicity of extract (HEScL) and silver nanoparticles (AgNPs-HEScL) from leaves. GC-MS, UV-Vis, EDX, FEG/SEM, DLS and zeta potential assays were used to characterize the extract or nanoparticles. Antimicrobial, antibiofilm and cytotoxicity analyses were carried out by methods: agar diffusion, microdilution and normal oral keratinocytes spontaneously immortalized (NOK-SI) cell culture. MICs of planktonic cells ranged from 31.2-250 (AgNPs-HEScL) to 1,296.8-10,375 μg/ml (HEScL) for , , , , , , , and . AgNPs-HEScL showed antibiofilm effects (125-8,000 μg/ml) toward , and , and and . The NOK-SI exhibited no cytotoxicity when treated with 32.8 and 680.3 μg/ml of AgNPs-HEScL and HEScL, respectively, for 5 min. The data suggest potential antimicrobial and antibiofilm action of HEScL, and more specifically, AgNPs-HEScL, involving pathogens of medical and dental interest (dose-, time- and species-dependent). The cytotoxicity of HEScL and AgNPs-HEScL detected in NOK-SI was dose- and time-dependent. This study presents toxicological information about the lyophilized ethanolic extract of leaves, including their metallic nanoparticles, and adds scientific values to incipient studies found in the literature.
PubMed: 36246249
DOI: 10.3389/fmicb.2022.995521