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Expert Review of Anti-infective Therapy 2016The HACEK group of bacteria - Haemophilus parainfluenzae, Aggregatibacter spp. (A. actinomycetemcomitans, A. aphrophilus, A. paraphrophilus, and A. segnis),... (Review)
Review
The HACEK group of bacteria - Haemophilus parainfluenzae, Aggregatibacter spp. (A. actinomycetemcomitans, A. aphrophilus, A. paraphrophilus, and A. segnis), Cardiobacterium spp. (C. hominis, C. valvarum), Eikenella corrodens, and Kingella spp. (K. kingae, K. denitrificans) - are fastidious gram-negative bacteria, part of the normal microbiota of oral and upper respiratory tract in humans. Although their pathogenicity is limited, they are responsible for 1-3% of all infective endocarditis. HACEK endocarditis mostly affect patients with underlying heart disease or prosthetic valves, and are characterized by an insidious course, with a mean diagnosis delay of 1 month (Haemophilus spp.) to 3 months (Aggregatibacter and Cardiobacterium spp.). The advent of continuously monitored blood culture systems with enriched media has erased the need for extended incubation for the diagnosis of HACEK endocarditis. Medical treatment relies on third-generation cephalosporin, with a favorable outcome in 80-90% of cases, with or without cardiac surgery.
Topics: Cephalosporins; Endocarditis, Bacterial; Gram-Negative Bacteria; Humans; Risk Factors
PubMed: 26953488
DOI: 10.1586/14787210.2016.1164032 -
Gut Jan 2018A history of periodontal disease and the presence of circulating antibodies to selected oral pathogens have been associated with increased risk of pancreatic cancer;...
OBJECTIVE
A history of periodontal disease and the presence of circulating antibodies to selected oral pathogens have been associated with increased risk of pancreatic cancer; however, direct relationships of oral microbes with pancreatic cancer have not been evaluated in prospective studies. We examine the relationship of oral microbiota with subsequent risk of pancreatic cancer in a large nested case-control study.
DESIGN
We selected 361 incident adenocarcinoma of pancreas and 371 matched controls from two prospective cohort studies, the American Cancer Society Cancer Prevention Study II and the National Cancer Institute Prostate, Lung, Colorectal and Ovarian Cancer Screening Trial. From pre-diagnostic oral wash samples, we characterised the composition of the oral microbiota using bacterial 16S ribosomal RNA (16S rRNA) gene sequencing. The associations between oral microbiota and risk of pancreatic cancer, controlling for the random effect of cohorts and other covariates, were examined using traditional and L1-penalised least absolute shrinkage and selection operator logistic regression.
RESULTS
Carriage of oral pathogens, and , were associated with higher risk of pancreatic cancer (adjusted OR for presence vs absence=1.60 and 95% CI 1.15 to 2.22; OR=2.20 and 95% CI 1.16 to 4.18, respectively). Phylum and its genus were associated with decreased pancreatic cancer risk (OR per per cent increase of relative abundance=0.94 and 95% CI 0.89 to 0.99; OR=0.87 and 95% CI 0.79 to 0.95, respectively). Risks related to these phylotypes remained after exclusion of cases that developed within 2 years of sample collection, reducing the likelihood of reverse causation in this prospective study.
CONCLUSIONS
This study provides supportive evidence that oral microbiota may play a role in the aetiology of pancreatic cancer.
Topics: Adenocarcinoma; Aged; Aggregatibacter actinomycetemcomitans; Carrier State; Case-Control Studies; Female; Fusobacteria; High-Throughput Nucleotide Sequencing; Humans; Male; Microbiota; Middle Aged; Mouth; Pancreatic Neoplasms; Periodontium; Porphyromonas gingivalis; Prospective Studies; Risk Factors
PubMed: 27742762
DOI: 10.1136/gutjnl-2016-312580 -
Journal of Infection in Developing... Nov 2021Development of bacterial resistance and antimicrobial side-effect has shifted the focus of research toward Ethnopharmacology. A biologically active compound derived from...
INTRODUCTION
Development of bacterial resistance and antimicrobial side-effect has shifted the focus of research toward Ethnopharmacology. A biologically active compound derived from the plants may increase the effectiveness of antibiotic when used in combination. The present study aims to determine the synergistic antibacterial effect of ethanolic extracts of Punica granatum (pericarp), Commiphora molmol, Azadirachta indica (bark) in combination with amoxicillin, metronidazole, tetracycline, and azithromycin on periodontopathic bacteria: Porphyromonas gingivalis, Tannerella forsythia, Treponema denticola and Aggregatibacter actinomycetemcomitans.
METHODOLOGY
Periodontopathic bacterial strains were isolated from the plaque sample that was collected from periodontitis patients and grown under favorable conditions. Susceptibility of bacteria to the antibiotics and extracts was determined by disc diffusion method by measuring the diameter of the inhibition zones. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of plant extracts were evaluated against each bacterium. Synergistic effect of plant extract in combination with antibiotics was tested against each bacterium by measuring the diameter of zone of inhibition (ZOI).
RESULTS
Findings revealed that all plant extracts exhibited an inhibitory effects on the proliferation and growth of periodontopathic bacteria. The maximum antibacterial effect was exhibited by C. molmol on P. gingivalis (ZOI = 20 ± 0.55 mm, MIC = 0.53 ± 0.24 mg/mL and MBC = 5.21 ± 1.81 mg/mL) (p < 0.05), meanwhile, no antibacterial activity was exhibited by P. granatum on T. forsythia. Synergistic antibacterial effect was recorded when plant extracts were used in combination with antibiotics. The best synergism was exhibited by P. granatum with amoxicillin against A. actinomycetemcomitans (24 ± 1.00 mm) (p < 0.05).
CONCLUSIONS
The synergistic test showed significant antibacterial activity when plant extracts were combined with antibiotics against all the experimented bacteria.
Topics: Aggregatibacter actinomycetemcomitans; Anti-Bacterial Agents; Drug Therapy, Combination; Humans; Microbial Sensitivity Tests; Periodontitis; Plant Extracts; Porphyromonas gingivalis; Tannerella forsythia
PubMed: 34898497
DOI: 10.3855/jidc.14904 -
Periodontology 2000 Feb 2020The etiopathogenesis of severe periodontitis includes herpesvirus-bacteria coinfection. This article evaluates the pathogenicity of herpesviruses (cytomegalovirus and... (Review)
Review
The etiopathogenesis of severe periodontitis includes herpesvirus-bacteria coinfection. This article evaluates the pathogenicity of herpesviruses (cytomegalovirus and Epstein-Barr virus) and periodontopathic bacteria (Aggregatibacter actinomycetemcomitans and Porphyromonas gingivalis) and coinfection of these infectious agents in the initiation and progression of periodontitis. Cytomegalovirus and A. actinomycetemcomitans/P. gingivalis exercise synergistic pathogenicity in the development of localized ("aggressive") juvenile periodontitis. Cytomegalovirus and Epstein-Barr virus are associated with P. gingivalis in adult types of periodontitis. Periodontal herpesviruses that enter the general circulation may also contribute to disease development in various organ systems. A 2-way interaction is likely to occur between periodontal herpesviruses and periodontopathic bacteria, with herpesviruses promoting bacterial upgrowth, and bacterial factors reactivating latent herpesviruses. Bacterial-induced gingivitis may facilitate herpesvirus colonization of the periodontium, and herpesvirus infections may impede the antibacterial host defense and alter periodontal cells to predispose for bacterial adherence and invasion. Herpesvirus-bacteria synergistic interactions, are likely to comprise an important pathogenic determinant of aggressive periodontitis. However, mechanistic investigations into the molecular and cellular interaction between periodontal herpesviruses and bacteria are still scarce. Herpesvirus-bacteria coinfection studies may yield significant new discoveries of pathogenic determinants, and drug and vaccine targets to minimize or prevent periodontitis and periodontitis-related systemic diseases.
Topics: Adult; Aggregatibacter actinomycetemcomitans; Cytomegalovirus; Herpesviridae; Herpesvirus 4, Human; Humans; Porphyromonas gingivalis
PubMed: 31850623
DOI: 10.1111/prd.12311 -
FASEB Journal : Official Publication of... Dec 2019Among the main bacteria implicated in the pathology of periodontal disease, () is well known for causing loss of periodontal attachment and systemic disease. Recent...
Among the main bacteria implicated in the pathology of periodontal disease, () is well known for causing loss of periodontal attachment and systemic disease. Recent studies have suggested that secreted extracellular RNAs (exRNAs) from several bacteria may be important in periodontitis, although their role is unclear. Emerging evidence indicates that exRNAs circulate in nanosized bilayered and membranous extracellular vesicles (EVs) known as outer membrane vesicles (OMVs) in gram-negative bacteria. In this study, we analyzed the small RNA expression profiles in activated human macrophage-like cells (U937) infected with OMVs from and investigated whether these cells can harbor exRNAs of bacterial origin that have been loaded into the host RNA-induced silencing complex, thus regulating host target transcripts. Our results provide evidence for the cytoplasmic delivery and activity of microbial EV-derived small exRNAs in host gene regulation. The production of TNF-α was promoted by exRNAs the TLR-8 and NF-κB signaling pathways. Numerous studies have linked periodontal disease to neuroinflammatory diseases but without elucidating specific mechanisms for the connection. We show here that intracardiac injection of OMVs in mice showed successful delivery to the brain after crossing the blood-brain barrier, the exRNA cargos increasing expression of TNF-α in the mouse brain. The current study indicates that host gene regulation by microRNAs originating from OMVs of the periodontal pathogen is a novel mechanism for host gene regulation and that the transfer of OMV exRNAs to the brain may cause neuroinflammatory diseases like Alzheimer's.-Han, E.-C., Choi, S.-Y., Lee, Y., Park, J.-W., Hong, S.-H., Lee, H.-J. Extracellular RNAs in periodontopathogenic outer membrane vesicles promote TNF-α production in human macrophages and cross the blood-brain barrier in mice.
Topics: Aggregatibacter actinomycetemcomitans; Animals; Bacterial Outer Membrane; Blood-Brain Barrier; Extracellular Vesicles; Gene Expression Profiling; Gene Expression Regulation; Host-Pathogen Interactions; Humans; Macrophages; Male; Mice; Mice, Inbred C57BL; MicroRNAs; Periodontal Diseases; RNA, Bacterial; RNA, Small Untranslated; Tumor Necrosis Factor-alpha; U937 Cells
PubMed: 31545910
DOI: 10.1096/fj.201901575R -
Journal of Dental Research Jul 2019The oral cavity contains a rich consortium of exopolysaccharide-producing microbes. These extracellular polysaccharides comprise a major component of the oral biofilm.... (Review)
Review
The oral cavity contains a rich consortium of exopolysaccharide-producing microbes. These extracellular polysaccharides comprise a major component of the oral biofilm. Together with extracellular proteins, DNA, and lipids, they form the biofilm matrix, which contributes to bacterial colonization, biofilm formation and maintenance, and pathogenesis. While a number of oral microbes have been studied in detail with regard to biofilm formation and pathogenesis, the exopolysaccharides have been well characterized for only select organisms, namely and . Studies on the exopolysaccharides of other oral organisms, however, are in their infancy. In this review, we present the current research on exopolysaccharides of oral microbes regarding their biosynthesis, regulation, contributions to biofilm formation and stability of the matrix, and immune evasion. In addition, insight into the role of exopolysaccharides in biofilms is highlighted through the evaluation of emerging techniques such as pH probing of biofilm colonies, solid-state nuclear magnetic resonance for macromolecular interactions within biofilms, and super-resolution microscopy analysis of biofilm development. Finally, exopolysaccharide as a potential nutrient source for species within a biofilm is discussed.
Topics: Aggregatibacter actinomycetemcomitans; Biofilms; Humans; Mouth; Polysaccharides, Bacterial; Streptococcus mutans
PubMed: 31009580
DOI: 10.1177/0022034519845001 -
Frontiers in Oral Health 2022Periodontitis is a dysbiotic disease caused by the interplay between the microbial ecosystem present in the disease with the dysregulated host immune response. The... (Review)
Review
Periodontitis is a dysbiotic disease caused by the interplay between the microbial ecosystem present in the disease with the dysregulated host immune response. The disease-associated microbial community is formed by the presence of established oral pathogens like as well as by newly dominant species like . These two oral pathogens prevail and grow within the periodontal pocket which highlights their ability to evade the host immune response. This review focuses on the virulence factors and potential pathogenicity of both oral pathogens in periodontitis, accentuating the recent description of virulence factors, including the presence of an exotoxin, and comparing them with the defined factors associated with . In the disease setting, possible synergistic and/or mutualistic interactions among both oral pathogens might contribute to disease progression.
PubMed: 36046121
DOI: 10.3389/froh.2022.981343 -
Archivos Peruanos de Cardiologia Y... 2023Infective endocarditis is a serious disease associated with high mortality despite recent advances in diagnosis and treatment. is a fastidious Gram-negative member of... (Review)
Review
Infective endocarditis is a serious disease associated with high mortality despite recent advances in diagnosis and treatment. is a fastidious Gram-negative member of the HACEK organisms ( spp., , , , and ). is associated with dental infections but has also been implicated in cases of infective endocarditis. We highlight the importance of a high index of suspicion in symptomatic patients with an initial negative blood culture, particularly in high-risk groups such as patients with congenital valve disease and prosthetic valve. The knowledge of this rare entity may lead to early diagnosis and appropriate management. We review the main characteristics of endocarditis reported in the medical literature.
PubMed: 38046225
DOI: 10.47487/apcyccv.v4i3.306 -
Pathogens (Basel, Switzerland) Nov 2019is a periodontal pathogen colonizing the oral cavity of a large proportion of the human population. It is equipped with several potent virulence factors that can cause... (Review)
Review
is a periodontal pathogen colonizing the oral cavity of a large proportion of the human population. It is equipped with several potent virulence factors that can cause cell death and induce or evade inflammation. Because of the large genetic diversity within the species, both harmless and highly virulent genotypes of the bacterium have emerged. The oral condition and age, as well as the geographic origin of the individual, influence the risk to be colonized by a virulent genotype of the bacterium. In the present review, the virulence and pathogenicity properties of will be addressed.
PubMed: 31698835
DOI: 10.3390/pathogens8040222 -
Cerebrovascular Diseases Extra 2018To systematically review the current literature investigating the association between oral health and acquired brain injury. (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
To systematically review the current literature investigating the association between oral health and acquired brain injury.
METHODS
A structured search strategy was applied to PubMed, Embase, Web of Science, and CENTRAL electronic databases until March 2017 by 2 independent reviewers. The preferred reporting items for systematic review and meta-analysis guidelines were used for systematic review.
RESULTS
Even though the objective was to assess the association between oral health and acquired brain injury, eligible studies focused solely on different forms of stroke and stroke subtypes. Stroke prediction was associated with various factors such as number of teeth, periodontal conditions (even after controlling for confounding factors), clinical attachment loss, antibody levels to Aggregatibacter actinomycetemcomitans and Prevotella intermedia. The literature showed no consensus on the possible association between gingivitis and stroke. Patients with stroke generally had poorer oral hygiene practices and oral health. Dental prophylaxis and professional intervention reduced the incidence of stroke.
CONCLUSIONS
Overall, oral health and stroke were related. Periodontitis and tooth loss were independently associated with stroke. However, prevention and timely intervention may reduce the risk of stroke. Stroke was the main cerebral lesion studied in the literature, with almost no publications on other brain lesions.
Topics: Aggregatibacter actinomycetemcomitans; Bacteroidaceae Infections; Brain Injuries; Cerebrovascular Disorders; Dental Prophylaxis; Female; Gingivitis; Humans; Incidence; Male; Oral Health; Oral Hygiene; Pasteurellaceae Infections; Periodontal Diseases; Periodontitis; Prevotella intermedia; Stroke; Tooth Loss
PubMed: 29402871
DOI: 10.1159/000484989