Treponema denticola Induces Epithelial Barrier Dysfunction in Polarized Epithelial Cells.

Treponema denticola, an anaerobic spirochete found mainly in the oral cavity, is associated with periodontal disease and has a variety of virulence factors. Although in vitro studies have shown that T. denticola is able to penetrate epithelial cell monolayers, its effect on the epithelial barrier junction is not known.

Antimicrobial Susceptibility of Microorganisms Isolated from Periapical Periodontitis Lesions.

Periapical periodontitis usually results from microbial infection, with these microorganisms occasionally migrating to the root canal, which can lead to further, potentially life-threatening, complications. Here, the susceptibility of 27 bacterial strains to various antimicrobial agents was evaluated. These strains comprised 13 species; 16 of the strains were clinical isolates from periapical lesions.

Expression of Porphyromonas gingivalis gingipain antigen Hgp44 domain on surface of Lactococcus lactis.

Porphyromonas gingivalis, a pathogen involved in the development of chronic periodontitis, has a number of major virulence factors, among which are its surface cysteine protease gingipains. The purpose of this study was to investigate the feasibility of inducing protective antibodies against P. gingivalis by means of immunization with recombinant Lactococcus lactis expressing the 44-kDa gingipain adhesion/hemagglutinin domain (Hgp44).

Effect of clinical factors on bacterial contamination of bone chips collected during implant surgery.

Purpose: The objective of this study was to investigate the relationship between various clinical factors and bacterial contamination of bone chips (BC) collected during dental implant surgery and to elucidate how bacterial contamination might be minimized.

Materials And Methods: Implants were installed in 55 partially edentulous patients (36 men and 19 women), among whom the relationship between various clinical factors and bacterial contamination of BC collected by bone trap was investigated in 37. The effect of rinsing with a saline on BC was determined in 18 patients.

Synergistic effect on biofilm formation between Fusobacterium nucleatum and Capnocytophaga ochracea.

The formation of dental plaque biofilm by specific Gram-negative rods and spirochetes plays an important role in the development of periodontal disease. The aim of this study was to characterize biofilm formation by Fusobacterium nucleatum and Capnocytophaga ochracea. Coaggregation between F.

Synergy in biofilm formation between Fusobacterium nucleatum and Prevotella species.

The formation of biofilm by anaerobic, Gram-negative bacteria in the subgingival crevice plays an important role in the development of chronic periodontitis. The aim of this study was to characterize the role of coaggregation between Fusobacterium nucleatum and Prevotella species in biofilm formation. Coaggregation between F.

HGP44 induces protection against Porphyromonas gingivalis-Induced alveolar bone loss in mice.

The protective effect of DNA vaccines expressing the Arg-gingipain A domain against bone loss induced by Porphyromonas gingivalis infection was investigated in a murine model. phgp44, which expresses the 44-kDa adhesion/hemagglutinin domain of Arg-gingipain A, prevented P. gingivalis-induced alveolar bone loss.

Effect of smoking on subgingival microflora of patients with periodontitis in Japan.

Background: Smoking is a risk factor for periodontitis. To clarify the contribution of smoking to periodontitis, it is essential to assess the relationship between smoking and the subgingival microflora. The aim of this study was to gain an insight into the influence of smoking on the microflora of Japanese patients with periodontitis.

Hemagglutinin/Adhesin domains of Porphyromonas gingivalis play key roles in coaggregation with Treponema denticola.

Porphyromonas gingivalis and Treponema denticola are major pathogens of periodontal disease. Coaggregation between microorganisms plays a key role in the colonization of the gingival crevice and the organization of periodontopathic biofilms. We investigated the involvement of surface ligands of P.

Exposure of P. gingivalis to noradrenaline reduces bacterial growth and elevates ArgX protease activity.

Objective: Periodontitis, an infectious disease caused by periodontopathic bacteria, including Porphyromonas gingivalis, is reported to be accelerated by stress, under which noradrenaline levels are increased in the bloodstream. The purpose of this study was to evaluate the effects of noradrenaline on P. gingivalis.

Fimbriae-associated genes are biofilm-forming factors in Aggregatibacter actinomycetemcomitans strains.

Aggregatibactor actinomycetemcomitans colonizes human periodontal lesions and is implicated in both aggressive periodontitis and chronic periodontitis. Clinical isolated colonies of A. actinomycetemcomitans were rough type.

Antimicrobial activity of super-oxidised water against oral microorganisms.

Objective: The radical anion of oxygen (O(-)) is extremely oxidative and shows high reactivity. In this study, the antibacterial activity of water super-oxidised water containing high concentration of O(-) (O(-)-water) was tested against cultured planktonic cells of cariogenic bacteria, periodontopathic bacteria and Candida albicans.

Methods: O(-)-water was prepared using the AOE-750 (Oxy Japan Corporation, Japan) and its antibacterial activity against pure culture of Streptococcus sobrinus, Porphyromonas gingivalis, Prevotella intermedia, Aggregatibacter actinomycetemcomitans, Fusobacterium nucleatum and C.

Transmission of periodontopathic bacteria from natural teeth to implants.

Purpose: Prevention of peri-implantitis is essential for the success of implant rehabilitation. Infection by periodontopathic bacteria is a major cause of peri-implantitis. The aim of the present study was to identify the source of peri-implant colonization by periodontopathic bacteria.

Congo red-binding protein in rough-phenotype Aggregatibacter actinomycetemcomitans is amyloid-like fiber.

Aggregatibacter actinomycetemcomitans is a pathogen associated with chronic and aggressive periodontitis and extra-oral infections. Fresh isolates of A. actinomycetemcomitans are fimbriated, forming small, rough-phenotype colonies on agar plates and also form biofilms.

Inhibitory effect of cranberry polyphenol on cariogenic bacteria.

The purpose of this study was to investigate the effect of cranberry polyphenol fraction on mutans streptococci. Hydrophobicity is an important factor in the adherence of bacteria to the tooth surface. We found that cranberry polyphenol fraction significantly decreased the hydrophobicity of Streptococcus sobrinus 6715, Streptococcus mutans MT8148R and JC2 in a dose-dependent manner (p<0.

Fusobacterium nucleatum enhances invasion of human gingival epithelial and aortic endothelial cells by Porphyromonas gingivalis.

Invasion by Porphyromonas gingivalis has been proposed as a possible mechanism of pathogenesis in periodontal and cardiovascular diseases. Porphyromonas gingivalis have direct access to the systemic circulation and endothelium in periodontitis patients by transient bacteremia. Periodontitis can be described as one of the predominant polymicrobial infections of humans.

Relationship between antimicrobial protein levels in whole saliva and periodontitis.

Background: Antimicrobial proteins are abundant in saliva. The purpose of this study was to determine and compare the amounts of two types of antibacterial protein, cystatin and lysozyme, in saliva between healthy persons and subjects with periodontitis.

Methods: Forty subjects with periodontitis visiting Tokyo Dental College Chiba Hospital, Chiba, Japan, and 27 healthy persons were evaluated.

Nicotine involved in periodontal disease through influence on cytokine levels.

Periodontal disease, for which smoking is a known risk factor, is infectious, and is associated with oral biofilm. Cytokines mediate and regulate immune and inflammatory responses. Lipopolysaccharide produced by periodontopathic bacteria plays a role in the progression of periodontitis.

Tongue-coating as risk indicator for aspiration pneumonia in edentate elderly.

Silent aspiration of oral microorganisms is a major cause of aspiration pneumonia. To establish oral hygiene criteria for the prevention of aspiration pneumonia in edentulous elderly persons, we investigated the relationship between presence of tongue-coating and number of oral bacteria in saliva and episodes of pneumonia. A total of 71 edentulous Japanese people aged 65 years or older living in nursing homes were enrolled in the study.

Treponema denticola induces interleukin-8 and macrophage chemoattractant protein 1 production in human umbilical vein epithelial cells.

Treponema denticola, a major pathogen of periodontitis, has also been detected in the lesions of atherosclerosis. The aim of this study was to investigate induction of chemokine production in human umbilical vein endothelial cells (HUVECs) by T. denticola and determine whether those chemokines were degraded by a protease, dentilisin.

Role of a Tannerella forsythia exopolysaccharide synthesis operon in biofilm development.

Tannerella forsythia is a Gram-negative oral anaerobe implicated in the development of periodontitis, a chronic inflammatory disease induced by bacterial infections which leads to tooth loss if untreated. Since biofilms formed by periodontal bacteria are considered important in disease progression and pose difficulties in treatment, we sought to investigate the underlying mechanisms of T. forsythia biofilm formation.

Susceptibility of Actinobacillus actinomycetemcomitans to six antibiotics decreases as biofilm matures.

Objectives: Actinobacillus actinomycetemcomitans is a major causative agent of chronic and aggressive periodontitis. Freshly isolated strains of A. actinomycetemcomitans display rough-type colonies and initiate biofilm formation on glass surfaces.

Oral flora in independent over 80-year-olds with more than 20 teeth.

The purpose of this study was to investigate oral flora in independent persons aged over 80 years with more than 20 remaining teeth. The subjects were 22 participants of the 8020 campaign (6 males and 16 females) with a mean age of 81.3+/-1.

Changes of immunoresponse in BALB/c mice neonatally treated with periodontopathic bacterial endotoxin.

The aim of this investigation was to analyze the effects of early life exposure to periodontopathic bacterial lipopolysaccharides on immunoresponse. Newborn BALB/c mice were subcutaneously injected with 20 ng lipopolysaccharide of Porphyromonas gingivalis, Actinobacillus actinomycetemcomitans or Escherichia coli daily for 2 days, starting within 24 h after birth. The treated mice were given intraperitoneal injections of bovine serum albumin at 180 and 187 days of age.

Production of protective antibodies against Porphyromonas gingivalis strains by immunization with recombinant gingipain domains.

We studied the effect of antibodies against Porphyromonas gingivalis gingipain domains, preparing them against three recombinant fragments of RgpA (catalytic domain, r-Rgp CAT; hemagglutinin domains, r-Rgp 44 and r-Rgps 15-27) and one fragment of Kgp (catalytic domain, r-Kgp CAT). Enhancement of opsonization and killing by human polymorphonuclear leukocytes were measured in the noninvasive FDC 381 and invasive W50 strains of P. gingivalis.