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Mikrobiyoloji Bulteni Apr 2020Prevotella species, being members of the human microbiota, are obligate anaerobic gram-negative bacteria. These organisms may cause opportunistic infections, including...
Prevotella species, being members of the human microbiota, are obligate anaerobic gram-negative bacteria. These organisms may cause opportunistic infections, including specific oral infections, local or systemic infections. A significant increase of resistance to some antimicrobials has been detected among Prevotella species. The frequency of resistance vary among isolates from different infection sources and between geographic locations. The knowledge about the antimicrobial susceptibility patterns of different Prevotella species is limited in Turkey. Providing the antimicrobial susceptibility data of these bacteria is very important for effective empirical treatment. In this study, we aimed to determine susceptibility data for 12 antimicrobial agents against Prevotella strains originating from human infections, collected in two centers in Turkey. A total of 118 Prevotella strains, isolated from different clinical samples in Marmara University Faculty of Medicine Medical Microbiology and Istanbul University Faculty of Dentistry Oral Microbiology Laboratories between January 2014-December 2017, were tested. Organisms were identified by using MALDI-TOF MS and by 16S rRNA gene sequencing. Minimal inhibitor concentrations of ampicillin, ampicillin-sulbactam, piperacillin-tazobactam, cefoxitin, meropenem, imipenem, clindamycin, tetracycline, tigecycline, moxifloxacin and metronidazole were determined using gradiyent test methodology (E-test; bioMerieux, France) and the European Committee on Antimicrobial Susceptibility Testing, Clinical and Laboratory Standards Institute and Food and Drug Administration guidelines were used for interpretation. Thirteen different Prevotella species were identified, Prevotella bivia and Prevotella nigrescens were the most prevalent species (n= 21) followed by Prevotella buccae (n= 19). All Prevotella strains were susceptible to piperacillin-tazobactam, cefoxitin, meropenem, imipenem and tigecycline. A total of 2 (1.7%) isolates were resistant to metronidazole and 1 (0.8%) isolate was intermediately resistant to ampicillin/sulbactam. The frequency of resistant isolates against ampicillin, clindamycin, tetracycline and moxifloxacin were 57.6%, 36.4%, 18% and 16.3%, respectively. In conclusion, piperacillin/tazobactam, cefoxitin, and tigecycline displayed high in vitro activity against Prevotella spp. and they all remained good candidates for empiric therapy. Imipenem and meropenem were also found to be very active, but the usage of carbapenems should be reserved for serious mixed infections, potentially accompanied by other resistant organisms. Intermediate resistance to ampicillinsulbactam and the resistance against metronidazole emphasized the need of periodic monitoring of their susceptibility patterns. The high rates of non-susceptibility to ampicillin, clindamycin, tetracycline and moxifloxacin indicated that these antimicrobials should not be used for treatment of infections without prior antimicrobial susceptibility testing.
Topics: Anti-Bacterial Agents; Bacteria, Anaerobic; Bacteroidaceae Infections; Humans; Microbial Sensitivity Tests; Prevotella; RNA, Ribosomal, 16S; Turkey
PubMed: 32723280
DOI: 10.5578/mb.69309 -
Microbiome Mar 2017Periodontitis results from the interaction between a subgingival biofilm and host immune response. Changes in biofilm composition are thought to disrupt homeostasis...
BACKGROUND
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.
METHODS
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.
RESULTS
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.
CONCLUSIONS
SLE is associated with differences in the composition of the microbiota, independently of periodontal status.
Topics: Adult; Bacteria; Bacteroides; Dental Plaque; Dysbiosis; Female; Gingiva; High-Throughput Nucleotide Sequencing; Humans; Interleukin-17; Interleukin-33; Interleukin-6; Lupus Erythematosus, Systemic; Male; Microbiota; Middle Aged; Periodontitis; RNA, Ribosomal, 16S; Young Adult
PubMed: 28320468
DOI: 10.1186/s40168-017-0252-z -
Cancer Prevention Research... Jan 2019The aim of this study was to investigate the associations between cervical microbiota and different human papillomavirus (HPV) infection statuses in cytologically normal...
The aim of this study was to investigate the associations between cervical microbiota and different human papillomavirus (HPV) infection statuses in cytologically normal women. The cervical microbiota of HPV-positive or -negative women with a normal cytologic diagnosis was characterized and compared using 16S rDNA-based high-throughput sequencing, and the differences in cervical microbiota associated with new acquisition, persistence, and clearances of HPV genotypes were analyzed via one-year follow-up. The results showed that the cervical microbial richness of HPV-positive women was lower than for HPV-negative women, and the difference was more significant in the postmenopausal group relative to the premenopausal group. and related taxa were associated with baseline HPV positivity, while , and genera and their related taxa and were associated with baseline HPV negativity. For HPV-positive women, the baseline abundance of was negatively associated with new HPV infection, , and ; and were positively associated with new HPV-type infection within the year of follow-up. was found to be negatively associated with persistent HPV infection and 9 taxa belonging to , and were found to be positively associated with persistence, and/or negatively associated with clearance of HPV types. We also observed 10 novel taxa associated with the clearance/persistence of HPV that had not been reported elsewhere. Those taxa associated with different infection statuses of HPV could be used as a biomarker to help predict the risk of developing persistent HPV infection.
Topics: Adult; Aged; Bacteria; Cervix Uteri; China; Cytodiagnosis; Female; Follow-Up Studies; Genotype; High-Throughput Nucleotide Sequencing; Humans; Incidence; Middle Aged; Papillomaviridae; Papillomavirus Infections; Prognosis; Uterine Cervical Neoplasms
PubMed: 30463989
DOI: 10.1158/1940-6207.CAPR-18-0233 -
International Journal of Nanomedicine 2020Biofilms protect bacteria from antibiotics and this can produce drug-resistant strains, especially the main pathogen of periodontitis, . Carbon quantum dots with various...
INTRODUCTION
Biofilms protect bacteria from antibiotics and this can produce drug-resistant strains, especially the main pathogen of periodontitis, . Carbon quantum dots with various biomedical properties are considered to have great application potential in antibacterial and anti-biofilm treatment.
METHODS
Tinidazole carbon quantum dots (TCDs) and metronidazole carbon quantum dots (MCDs) were prepared by a hydrothermal method with the clinical antibacterial drugs tinidazole and metronidazole, respectively. Then, TCDs and MCDs were characterized by transmission electron microscopy, UV-visible spectroscopy, infrared spectroscopy and energy-dispersive spectrometry. The antibacterial effects were also investigated under different conditions.
RESULTS
The TCDs and MCDs had uniform sizes. The results of UV-visible and energy-dispersive spectrometry confirmed their important carbon polymerization structures and the activity of the nitro group, which had an evident inhibitory effect on , but almost no effect on other bacteria, including , and . Importantly, the TCDs could penetrate the biofilms to further effectively inhibit the growth of under the biofilms. Furthermore, it was found that the antibacterial effect of TCDs lies in its ability to impair toxicity by inhibiting the major virulence factors and related genes involved in the biofilm formation of , thus affecting the self-assembly of biofilm-related proteins.
CONCLUSION
The findings demonstrate a promising new method for improving the efficiency of periodontitis treatment by penetrating the biofilm with preparations of nano-level antibacterial drugs.
Topics: Animals; Anti-Bacterial Agents; Bacterial Adhesion; Biofilms; Carbon; Escherichia coli; Gene Expression Regulation, Bacterial; Humans; Metronidazole; Microbial Sensitivity Tests; Microscopy, Electron, Transmission; Periodontitis; Porphyromonas gingivalis; Quantum Dots; Rabbits; Spectrophotometry, Ultraviolet; Staphylococcus aureus; Tinidazole; Virulence Factors
PubMed: 32801701
DOI: 10.2147/IJN.S253416 -
BMC Oral Health May 2015Plasminogen deficiency is a rare autosomal recessive disease, which is associated with aggressive periodontitis and gingival enlargement. Previously described treatments...
BACKGROUND
Plasminogen deficiency is a rare autosomal recessive disease, which is associated with aggressive periodontitis and gingival enlargement. Previously described treatments of plasminogen deficiency associated periodontitis have shown limited success. This is the first case report indicating a successful therapy approach consisting of a non-surgical supra- and subgingival debridement in combination with an adjunctive systemic antibiotic therapy and a strict supportive periodontal regimen over an observation period of 4 years.
CASE PRESENTATION
The intraoral examination of a 17-year-old Turkish female with severe plasminogen deficiency revealed generalized increased pocket probing depths ranging from 6 to 9 mm, bleeding on probing over 30%, generalized tooth mobility, and gingival hyperplasia. Alveolar bone loss ranged from 30% to 50%. Clinical attachment loss corresponded to pocket probing depths. Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Treponema denticola, Prevotella intermedia, Prevotella nigrescens and Eikenella corrodens have been detected by realtime polymerase chain reaction. Periodontal treatment consisted of full mouth disinfection and adjunctive systemic administration of amoxicillin (500 mg tid) and metronidazole (400 mg tid). A strict supportive periodontal therapy regimen every three month in terms of supra- and subgingival debridement was rendered. The reported therapy has significantly improved periodontal health and arrested disease progression. Intraoral examination at the end of the observation period 3.5 years after non-surgical periodontal therapy showed generalized decreased pocket probing depths ranging from 1 to 6 mm, bleeding on probing lower 30%, and tooth mobility class I and II. Furthermore, microbiological analysis shows the absence of Porphyromonas gingivalis, Prevotella intermedia and Treponema denticola after therapy.
CONCLUSION
Adjunctive antibiotic treatment may alter the oral microbiome and thus, the inflammatory response of periodontal disease associated to plasminogen deficiency and diminishes the risk of pseudomembrane formation and progressive attachment loss. This case report indicates that patients with plasminogen deficiency may benefit from non-surgical periodontal treatment in combination with an adjunctive antibiotic therapy and a strict supportive periodontal therapy regimen.
Topics: Adolescent; Alveolar Bone Loss; Amoxicillin; Anti-Bacterial Agents; Combined Modality Therapy; Conjunctivitis; Female; Follow-Up Studies; Gingival Hemorrhage; Gingival Hyperplasia; Humans; Metronidazole; Periodontal Attachment Loss; Periodontal Debridement; Periodontal Pocket; Periodontitis; Plasminogen; Skin Diseases, Genetic; Tooth Mobility
PubMed: 25971786
DOI: 10.1186/s12903-015-0045-3 -
Anaerobe Dec 2018The accuracy of a phenotypic scheme to recognize periodontal Prevotella intermedia/nigrescens group clinical isolates on primary isolation culture plates was assessed...
The accuracy of a phenotypic scheme to recognize periodontal Prevotella intermedia/nigrescens group clinical isolates on primary isolation culture plates was assessed with matrix-assisted laser desorption-ionization time-of-flight mass spectrometry (MALDI-TOF MS). A total of 84 fresh subgingival isolates from 23 chronic periodontitis patients were presumptively recognized on anaerobically-incubated enriched Brucella blood agar primary isolation plates as P. intermedia/nigrescens based on their dark-pigmented colony morphology, brick-red autofluorescence under long-wave ultraviolet light, and a negative fluorescence test for lactose production. The presumptive P. intermedia/nigrescens clinical isolates were subjected to MALDI-TOF MS analysis using Bruker MALDI Biotyper analytic software containing mass spectra for P. intermedia and Prevotella nigrescens in its reference library of bacterial protein profiles. Using a ≥1.7 log score agreement threshold, 60 (71.4%) of the presumptive P. intermedia/nigrescens clinical isolates were confirmed as either P. intermedia (25 isolates) or P. nigrescens (35 isolates). All isolates with a <1.7 log score were also identified as P. intermedia or P. nigrescens from the top choice designated on the MALDI Biotyper most likely species identification list. These MALDI-TOF MS findings document the ability of the phenotypic scheme to correctly recognize most periodontal P. intermedia/nigrescens group clinical isolates on primary isolation culture plates.
Topics: Adult; Bacterial Typing Techniques; Bacteroidaceae Infections; Chronic Periodontitis; Female; Humans; Male; Phenotype; Prevotella intermedia; Prevotella nigrescens; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
PubMed: 29913204
DOI: 10.1016/j.anaerobe.2018.06.007 -
PloS One 2015It is well known that strain and virulence diversity exist within the population structure of Porphyromonas gingivalis. In the present study we investigate intra- and...
Intraspecies Variability Affects Heterotypic Biofilms of Porphyromonas gingivalis and Prevotella intermedia: Evidences of Strain-Dependence Biofilm Modulation by Physical Contact and by Released Soluble Factors.
It is well known that strain and virulence diversity exist within the population structure of Porphyromonas gingivalis. In the present study we investigate intra- and inter-species variability in biofilm formation of Porphyromonas gingivalis and partners Prevotella intermedia and Prevotella nigrescens. All strains tested showed similar hydrophobicity, except for P. gingivalis W83 which has roughly half of the hydrophobicity of P. gingivalis ATCC33277. An intraspecies variability in coaggregation of P. gingivalis with P. intermedia was also found. The association P. gingivalis W83/P. intermedia 17 produced the thickest biofilm and strain 17 was prevalent. In a two-compartment system P. gingivalis W83 stimulates an increase in biomass of strain 17 and the latter did not stimulate the growth of P. gingivalis W83. In addition, P. gingivalis W83 also stimulates the growth of P. intermedia ATCC25611 although strain W83 was prevalent in the association with P. intermedia ATCC25611. P. gingivalis ATCC33277 was prevalent in both associations with P. intermedia and both strains of P. intermedia stimulate the growth of P. gingivalis ATCC33277. FISH images also showed variability in biofilm structure. Thus, the outcome of the association P. gingivalis/P. intermedia seems to be strain-dependent, and both soluble factors and physical contact are relevant. The association P. gingivalis-P. nigrescens ATCC33563 produced larger biomass than each monotypic biofilm, and P. gingivalis was favored in consortia, while no differences were found in the two-compartment system. Therefore, in consortia P. gingivalis-P. nigrescens physical contact seems to favor P. gingivalis growth. The intraspecies variability found in our study suggests strain-dependence in ability of microorganisms to recognize molecules in other bacteria which may further elucidate the dysbiosis event during periodontitis development giving additional explanation for periodontal bacteria, such as P. gingivalis and P. intermedia, among others, to persist and establish chronic infections in the host.
Topics: Bacterial Adhesion; Biofilms; Biomass; Dysbiosis; Humans; Periodontitis; Porphyromonas gingivalis; Prevotella intermedia
PubMed: 26406499
DOI: 10.1371/journal.pone.0138687 -
PloS One 2020Several cohort studies have shown that periodontal disease is associated with an increased risk for stroke. However, it remains unclear whether serum antibody titers for...
Several cohort studies have shown that periodontal disease is associated with an increased risk for stroke. However, it remains unclear whether serum antibody titers for a specific periodontal pathogen are associated with outcome after ischemic stroke, and which kinds of pathogens are associated with ischemic stroke. We examined the relationship between serum IgG titers to periodontal pathogens and outcome in ischemic stroke patients. A total of 445 patients with acute ischemic stroke (194 female [44.0%], mean age 71.9±12.3 years) were registered in this study. Serum IgG titers to 9 periodontal pathogens (Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans, Prevotella intermedia, Prevotella nigrescens, Fusobacterium nucleatum, Treponema denticola, Tannerella forsythensis, Campylobacter rectus, Eikenella corrodens) were evaluated using the enzyme-linked immunosorbent assay (ELISA) method. An unfavorable outcome was defined as a 3 or higher on the modified Rankin Scale. The proportion of patients with unfavorable outcome was 25.4% (113 patients). Based on multivariate logistic regression analysis, numbers of IgG antibodies positive for periodontal pathogens (odds ratio 1.20, 95% CI 1.02-1.41, p = 0.03) were independent predictors of unfavorable outcome in ischemic stroke patients.
Topics: Aged; Aged, 80 and over; Aggressive Periodontitis; Antibodies, Bacterial; Brain Ischemia; Comorbidity; Female; Humans; Immunoglobulin G; Male; Middle Aged; Serologic Tests; Stroke; Treatment Outcome
PubMed: 32760103
DOI: 10.1371/journal.pone.0237185 -
Journal of Periodontal Research Oct 2016This study aimed to assess the effect of multiple sessions of a low-level laser therapy (LLLT) adjuvant to scaling and root planing (SRP) on the treatment of...
BACKGROUND AND OBJECTIVE
This study aimed to assess the effect of multiple sessions of a low-level laser therapy (LLLT) adjuvant to scaling and root planing (SRP) on the treatment of experimental periodontitis (EP) in rats treated with 5-fluorouracil (5-FU).
MATERIAL AND METHODS
A total of 120 rats were divided into five groups: no treatment (NT); treatment with 5-FU (60 and 40 mg/kg) and no local periodontal treatment (5FU); treatment with 5-FU and SRP (5FU-SRP); treatment with 5-FU, SRP and one LLLT session (660 nm; 0.035 W; 4.2 J; 120 s) (5FU-SRP-1LLLT); and treatment with 5-FU, SRP and four LLLT sessions (0, 24, 48 and 72 h) (5FU-SRP-4LLLT). EP was induced in the mandibular molars through ligature placement. The alveolar bone loss (ABL) area in the furcation region was analysed histometrically. TRAP, proliferating cell nuclear antigen, RANKL, osteoprotegerin and activated caspase-3 patterns were analysed by immunolabeling. Prostaglandin E2 was quantified using an ELISA, and tumour necrosis factor α and interleukin-6 were assessed using the multiplex method. The prevalence rates of Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Prevotella nigrescens, Prevotella intermedia and Fusobacterium nucleatum were assessed using the PCR method. The data were subjected to statistical analysis (α = 5%).
RESULTS
5FU, 5FU-SRP and 5FU-SRP-1LLLT treatment groups showed higher ABL compared with the NT group (p < 0.05), whereas the 5FU-SRP-4LLLT group showed lower ABL compared with the 5FU group on day 7 and decreased RANKL immunolabeling (p < 0.05).
CONCLUSION
Treatment with 5-FU worsened EP, and multiple LLLT sessions adjuvant to SRP seemed to improve periodontitis in rats subjected to 5-FU chemotherapy.
Topics: Alveolar Bone Loss; Animals; Bacteria; Caspase 3; Combined Modality Therapy; Dental Scaling; Dinoprostone; Drug Therapy; Fluorouracil; Inflammation; Interleukin-6; Low-Level Light Therapy; Male; Mandible; Molar; Osteoprotegerin; Periodontitis; RANK Ligand; Rats; Rats, Wistar; Root Planing; Tumor Necrosis Factor-alpha
PubMed: 26750739
DOI: 10.1111/jre.12347 -
The Journal of Biological Chemistry Sep 2021Modular protein assembly has been widely reported as a mechanism for constructing allosteric machinery. Recently, a distinctive allosteric system has been identified in...
Modular protein assembly has been widely reported as a mechanism for constructing allosteric machinery. Recently, a distinctive allosteric system has been identified in a bienzyme assembly comprising a 3-deoxy-d-arabino heptulosonate-7-phosphate synthase (DAH7PS) and chorismate mutase (CM). These enzymes catalyze the first and branch point reactions of aromatic amino acid biosynthesis in the bacterium Prevotella nigrescens (PniDAH7PS), respectively. The interactions between these two distinct catalytic domains support functional interreliance within this bifunctional enzyme. The binding of prephenate, the product of CM-catalyzed reaction, to the CM domain is associated with a striking rearrangement of overall protein conformation that alters the interdomain interactions and allosterically inhibits the DAH7PS activity. Here, we have further investigated the complex allosteric communication demonstrated by this bifunctional enzyme. We observed allosteric activation of CM activity in the presence of all DAH7PS substrates. Using small-angle X-ray scattering (SAXS) experiments, we show that changes in overall protein conformations and dynamics are associated with the presence of different DAH7PS substrates and the allosteric inhibitor prephenate. Furthermore, we have identified an extended interhelix loop located in CM domain, loop, as a crucial segment for the interdomain structural and catalytic communications. Our results suggest that the dual-function enzyme PniDAH7PS contains a reciprocal allosteric system between the two enzymatic moieties as a result of this bidirectional interdomain communication. This arrangement allows for a complex feedback and feedforward system for control of pathway flux by connecting the initiation and branch point of aromatic amino acid biosynthesis.
Topics: 3-Deoxy-7-Phosphoheptulonate Synthase; Allosteric Regulation; Amino Acid Sequence; Amino Acids, Aromatic; Bacterial Proteins; Biosynthetic Pathways; Enzyme Inhibitors; Prevotella nigrescens; Protein Domains; Scattering, Small Angle; Sequence Alignment
PubMed: 34343567
DOI: 10.1016/j.jbc.2021.101038