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Microorganisms Jan 2019Nowadays cancer is the second main cause of death in the world. The most known bacterial carcinogen is . Pathogens that can have an impact on cancer development in the... (Review)
Review
Nowadays cancer is the second main cause of death in the world. The most known bacterial carcinogen is . Pathogens that can have an impact on cancer development in the gastrointestinal tract are also found in the oral cavity. Some specific species have been identified that correlate strongly with oral cancer, such as sp., sp., sp., sp., , and . Many works have also shown that the oral periopathogens and play an important role in the development of colorectal and pancreatic cancer. Three mechanisms of action have been suggested in regard to the role of oral microbiota in the pathogenesis of cancer. The first is bacterial stimulation of chronic inflammation. Inflammatory mediators produced in this process cause or facilitate cell proliferation, mutagenesis, oncogene activation, and angiogenesis. The second mechanism attributed to bacteria that may influence the pathogenesis of cancers by affecting cell proliferation is the activation of NF-κB and inhibition of cellular apoptosis. In the third mechanism, bacteria produce some substances that act in a carcinogenic manner. This review presents potentially oncogenic oral bacteria and possible mechanisms of their action on the carcinogenesis of human cells.
PubMed: 30642137
DOI: 10.3390/microorganisms7010020 -
Oncology Letters Apr 2020Oral squamous cell carcinoma (OSCC) is the leading cause of mortality for oral cancer. Numerous risk factors mainly related to unhealthy habits and responsible for... (Review)
Review
Oral squamous cell carcinoma (OSCC) is the leading cause of mortality for oral cancer. Numerous risk factors mainly related to unhealthy habits and responsible for chronic inflammation and infections have been recognized as predisposing factors for oral carcinogenesis. Recently, even microbiota alterations have been associated with the development of human cancers. In particular, some specific bacterial strains have been recognized and strongly associated with oral cancer development ( and .). Several hypotheses have been proposed to explain how the oral microbiota could be involved in cancer pathogenesis by mainly paying attention to chronic inflammation, microbial synthesis of cancerogenic substances, and alteration of epithelial barrier integrity. Based on knowledge of the carcinogenic effects of dysbiosis, it was recently suggested that probiotics may have anti-tumoral activity. Nevertheless, few data exist with regard to probiotic effects on oral cancer. On this basis, the association between the development of oral cancer and oral dysbiosis is discussed focusing attention on the potential benefits of probiotics administration in cancer prevention.
PubMed: 32211076
DOI: 10.3892/ol.2020.11441 -
International Journal of Molecular... Jul 2022A complex balanced equilibrium of the bacterial ecosystems exists in the oral cavity that can be altered by tobacco smoking, psychological stressors, bad dietary habit,... (Review)
Review
A complex balanced equilibrium of the bacterial ecosystems exists in the oral cavity that can be altered by tobacco smoking, psychological stressors, bad dietary habit, and chronic periodontitis. Oral dysbiosis can promote the onset and progression of oral squamous cell carcinoma (OSCC) through the release of toxins and bacterial metabolites, stimulating local and systemic inflammation, and altering the host immune response. During the process of carcinogenesis, the composition of the bacterial community changes qualitatively and quantitatively. Bacterial profiles are characterized by targeted sequencing of the 16S rRNA gene in tissue and saliva samples in patients with OSCC. , , , , , and are the significantly increased bacteria in salivary samples. These have a potential diagnostic application to predict oral cancer through noninvasive salivary screenings. Oral lactic acid bacteria, which are commonly used as probiotic therapy against various disorders, are valuable adjuvants to improve the response to OSCC therapy.
Topics: Bacteria; Carcinoma, Squamous Cell; Humans; Microbiota; Mouth Neoplasms; RNA, Ribosomal, 16S
PubMed: 35955456
DOI: 10.3390/ijms23158323 -
Journal of Investigative Medicine High... 2021Odontogenic bacteremia, most commonly involving gram-positive oral flora, can result from daily self-care practices or professional dental procedures. Though usually...
Odontogenic bacteremia, most commonly involving gram-positive oral flora, can result from daily self-care practices or professional dental procedures. Though usually transient and quickly cleared by the immune system, the presence of periodontal disease increases the frequency of exposure and risk of persistence of oral-systemic infections. Comorbidities such as asplenia, alcoholism, and immunocompromise increase the risk of complications of hematogenous spread and severe systemic illness. is a genus of anaerobic fastidious gram-negative bacilli, which is a common member of human oral flora, and its density is proportional to mass of dental plaques and periodontal diseases. spp that colonize humans are less virulent and are uncommon causes of bacteremia when compared with the typical of canines. has been rarely reported as a cause of disease in immunocompromised or immunocompetent hosts. In this article, we present a case of an immunocompromised 70-year-old man with poor oral hygiene, on methotrexate and prednisone for rheumatoid arthritis and sarcoidosis, who was admitted for chronic obstructive pulmonary disease exacerbation and developed bacteremia and septic shock after an episode of upper gastrointestinal bleeding. Poor oral hygiene in our patient is believed to have increased his risk as an immunocompromised patient to developing bacteremia. This case highlights the importance of oral care in immunocompromised patients especially while hospitalized, and those about to receive transplant, chemotherapy, or on immune modulators.
Topics: Aged; Bacteremia; Capnocytophaga; Gastrointestinal Hemorrhage; Gram-Negative Bacterial Infections; Humans; Immunocompromised Host; Male
PubMed: 34041953
DOI: 10.1177/23247096211020672 -
Journal of Oral and Maxillofacial... 2022are facultative anaerobic Gram-negative bacilli and recognized as opportunistic pathogens of various extraoral infections. Only a few studies attempted to identify all...
Comparison of culture and polymerase chain reaction-restriction fragment length polymorphism for identification of various species from subgingival plaque samples of healthy and periodontally diseased individuals.
INTRODUCTION
are facultative anaerobic Gram-negative bacilli and recognized as opportunistic pathogens of various extraoral infections. Only a few studies attempted to identify all the seven species of phenotypically and genotypically in healthy individuals and patients with chronic periodontitis. Studies to determine the prevalence of in subgingival plaque samples from healthy individuals, chronic gingivitis and periodontitis among Indian population are lacking.
AIM
The aim of this study was to identify and compare the presence of species phenotypically through microbial culture and biochemical tests and genotypically through polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) in subgingival plaque of healthy individuals and patients with chronic gingivitis and chronic periodontitis.
MATERIALS AND METHODS
A total of 300 subjects, 100 each with gingivitis, periodontitis and periodontally healthy gingiva subjected, were included. Subgingival plaque was collected and was cultured for phenotypic identification (microbial culture and biochemical test), and for genotypic identification, DNA extraction was done and PCR-RFLP analysis was performed to identify the genus and also to identify different species of .
RESULTS
Of 300 individuals, species were identified from 237 (79%) individuals by PCR and 82 (27.33%) by culture. The prevalence of was found to be higher with both the methods followed by and . , and were isolated only by culture with very low prevalence that is 1.33%, 1.33% and 0.66%, respectively. We could not get any isolate of by any of the two methods.
CONCLUSION
species could be found in gingival sulci as well as periodontal pockets and can be detected by culture and PCR-RFLP. However, higher prevalence of these species in healthy compared to disease requires further analysis to determine their role in healthy and diseased periodontium.
PubMed: 35968170
DOI: 10.4103/jomfp.jomfp_172_21 -
Microbiology Spectrum Aug 2023Physical forces that arise due to bacterial motility and growth play a significant role in shaping the biogeography of the human oral microbiota. Bacteria of the genus...
Physical forces that arise due to bacterial motility and growth play a significant role in shaping the biogeography of the human oral microbiota. Bacteria of the genus are abundant in the human oral microbiota and yet very little is known about their physiology. The human oral isolate Capnocytophaga gingivalis exhibits robust gilding motility that is driven by the rotary type 9 secretion system (T9SS), and cells of transport nonmotile oral microbes as cargo. Phages, i.e., viruses that infect bacteria, are found in abundance within the microbiota. By tracking fluorescently labeled lambda phages that do not infect , we report active phage transportation by swarms. Lambda phage-carrying swarms were propagated near an Escherichia coli colony. The rate of disruption of the E. coli colony increased 10 times compared with a control where phages simply diffused to the E. coli colony. This finding suggests a mechanism where fluid flows produced by motile bacteria increase the rate of transport of phages to their host bacterium. Additionally, swarms formed tunnel-like structures within a curli fiber-containing E. coli biofilm that increased the efficiency of phage penetration. Our data suggest that invasion by a swarm changes the spatial structure of the prey biofilm and further increases the penetration of phages. Dysbiosis of the human oral microbiota is associated with several diseases, but the factors that shape the biogeography of the oral microbiota are mostly opaque. Biofilms that form in the human supragingival and subgingival regions have a diverse microbial community where some microbes form well-defined polymicrobial structures. , a bacterium abundant in human gingival regions, has robust gliding motility that is powered by the type 9 secretion system. We demonstrate that swarms of can transport phages through a complex biofilm which increases the death rate of the prey biofilm. These findings suggest that could be used as a vehicle for the transportation of antimicrobials and that active phage transportation could shape the spatial structure of a microbial community.
Topics: Humans; Bacteriophages; Escherichia coli; Bacteria; Biofilms; Microbiota
PubMed: 37358420
DOI: 10.1128/spectrum.00937-23 -
Life (Basel, Switzerland) Oct 2022Increasing the disinfection during non-surgical treatment of periodontitis is primordial. This study assesses the effectiveness of sodium hypochlorite and a 980 nm diode...
Increasing the disinfection during non-surgical treatment of periodontitis is primordial. This study assesses the effectiveness of sodium hypochlorite and a 980 nm diode laser in non-surgical treatment of periodontitis. Thirty sites of localized periodontitis with a probing pocket depth (PPD) of ≥ 6 mm were included. Fifteen underwent scaling root planing (SRP group) and 15 underwent SRP + 0.5% NaOCl and a 980 nm diode laser (study group). A biological molecular test and real time polymerase chain reaction (RT-PCR) were performed before (T0) and after intervention (T1). Total bacterial count and counts of Porphyromonas gingivalis, Treponema denticola, Tannerella forsythia, Prevotella intermedia, Peptostreptococcus micros, Fusobacterium nucleatum, Aggregatibacter actinomycetemcomitans, Eubacterium nodatum, Capnocytophaga gingivalis were assessed. Plaque index (PI), bleeding on probing (BOP), gingival recession (GR), PPD and clinical attachment loss (CAL) were evaluated at T0, and 3 and 6 months after. Study group showed a statistically significant reduction of TBC (5.66 × 10 CFU/mL) compared to SRP (6.2 × 10 CFU/mL). Both groups showed a statistically significant reduction of Treponema denticola, Tannerella forsythia, Prevotella intermedia, Peptostrep. (micromonas) micros and Fusobacterium nucleatum; however, a significant reduction of Eubacterium nodatum and Capnocytophaga gingivalis was observed in the study group. At T6, both groups had a statistically significant reduction of PI, BOP, GR, PD and CAL. The study group showed more GR compared to SRP and a significant reduction of PD (4.03 mm ± 0.49) compared to SRP (5.28 mm ± 0.67). This study reveals that NaOCl and a diode laser are effective as an adjunctive to the non-surgical treatment of periodontitis.
PubMed: 36295072
DOI: 10.3390/life12101637 -
The Journal of Antimicrobial... Aug 2017Capnocytophaga spp. are often reported to cause bacteraemia and extra-oral infections and are characterized by their significant contribution to resistance to β-lactam...
OBJECTIVES
Capnocytophaga spp. are often reported to cause bacteraemia and extra-oral infections and are characterized by their significant contribution to resistance to β-lactam and macrolide-lincosamide-streptogramin antibiotics in the human oral microbiota. The implication of mutations in the quinolone resistance-determining region (QRDR) of DNA gyrase A and B ( gyrA and gyrB ) and topoisomerase IV ( parC and parE ) of fluoroquinolone (FQ)-resistant Capnocytophaga spp., hitherto unknown, was explored in this study.
METHODS
Two reference strains ( Capnocytophaga gingivalis ATCC 33624 and Capnocytophaga sputigena ATCC 33612) and four Capnocytophaga spp. isolated from clinical samples were studied. Nine in vitro FQ-resistant mutants, derived from two reference strains and one FQ-susceptible clinical isolate, were selected by successive inoculations onto medium containing levofloxacin. MICs of ofloxacin, norfloxacin, ciprofloxacin, levofloxacin and moxifloxacin were determined. The presumed QRDRs of GyrA, GyrB, ParC and ParE from Capnocytophaga spp. were determined by sequence homology to Bacteroides fragilis and Escherichia coli . PCR primers were designed to amplify the presumed QRDR genetic region of Capnocytophaga spp. and sequence analyses were performed using the BLAST program at the National Center for Biotechnology Information.
RESULTS AND CONCLUSIONS
gyrA mutations leading to a substitution from amino acid position 80 to 86 were systematically detected in Capnocytophaga spp. with ciprofloxacin MIC >1 mg/L and considered as the primary target of FQs. No mutational alteration in the QRDR of gyrB was detected. Other mutations in parC and parE led to spontaneous amino acid substitutions of DNA topoisomerase IV subunit B with no alteration in FQ susceptibility.
Topics: Amino Acid Substitution; Anti-Bacterial Agents; Capnocytophaga; DNA Gyrase; DNA Topoisomerase IV; Fluoroquinolones; Gram-Negative Bacterial Infections; Humans; Microbial Sensitivity Tests; Mutation, Missense; Polymerase Chain Reaction; Sequence Analysis, DNA
PubMed: 28453633
DOI: 10.1093/jac/dkx119 -
Pathogens (Basel, Switzerland) Jul 2023Areca nut and slaked lime, with or without tobacco wrapped in leaf, prepared as betel quid, is extensively consumed as a masticatory product in many countries across... (Review)
Review
Areca nut and slaked lime, with or without tobacco wrapped in leaf, prepared as betel quid, is extensively consumed as a masticatory product in many countries across the world. Betel Quid can promote the malignant transformation of oral lesions as well as trigger benign cellular and molecular changes. In the oral cavity, it causes changes at the compositional level in oral microbiota called dysbiosis. This dysbiosis may play an important role in Oral Cancer in betel quid chewers. The abnormal presence and increase of bacteria , , , sp., , and in saliva and/or other oral sites of the cancer patients has attracted frequent attention for its association with oral cancer development. In the present review, the authors have analysed the literature reports to revisit the oncogenic potential of betel quid and oral microbiome alterations, evaluating the potential of oral microbiota both as a driver and biomarker of oral cancer. The authors have also shared a perspective that the restoration of local microbiota can become a potentially therapeutic or prophylactic strategy for the delay or reversal of lip and oral cavity cancers, especially in high-risk population groups.
PubMed: 37623956
DOI: 10.3390/pathogens12080996 -
International Journal of Molecular... Jan 2023The purpose of this study was to characterize and compare subgingival microbiome before and after periodontal treatment to learn if any changes of the subgingival...
The purpose of this study was to characterize and compare subgingival microbiome before and after periodontal treatment to learn if any changes of the subgingival microbiome were reflected in intra-oral halitosis. We tested the hypothesis that intra-oral halitosis (Volatile sulfur compounds levels) correlates with corresponding subgingival bacterial levels before and after periodontal treatment. Twenty patients with generalized periodontitis completed the study. Subgingival plaque samples were collected at baseline and 6-8 weeks after nonsurgical periodontal therapy. Full-mouth periodontal status assessed probing depth (PD), clinical attachment loss (CAL), gingival recession (REC), bleeding on probing (BoP), PISA and PESA. Halitosis assessment was made using a volatile sulfur compounds (VSC) detector device. Periodontal measures were regressed across VSC values using adjusted multivariate linear analysis. The subgingival microbiome was characterized by sequencing on an Illumina platform. From a sample of 20 patients referred to periodontal treatment, 70% were females ( = 14), with a mean age of 56.6 (±10.3) years; full-mouth records of PD, CAL, BOP (%) allowed to classify the stage and grade of periodontitis, with 45% ( 9) of the sample having Periodontitis Stage IV grade C and 95% ( = 19) had generalized periodontitis. The correlation of bacterial variation with VSCs measured in the periodontal diagnosis and in the reassessment after treatment were evaluated. , and showed correlation with the reduction of VSC after periodontal treatment (-value = 0.044; 0.047 and 0.004, respectively). had a significant reverse correlation between VSCs variation from diagnosis (baseline) and after treatment. Microbial diversity was high in the subgingival plaque on periodontitis and intra-oral halitosis participants of the study. Furthermore, there were correlations between subgingival plaque composition and VSC counting after periodontal treatment. The subgingival microbiome can offer important clues in the investigation of the pathogenesis and treatment of halitosis.
Topics: Female; Humans; Middle Aged; Male; Halitosis; Periodontitis; Bacteria; Sulfur Compounds; Fusobacterium nucleatum
PubMed: 36768839
DOI: 10.3390/ijms24032518