Identification of key determinants in Porphyromonas gingivalis host-cell invasion assays.

The periodontal pathogen Porphyromonas gingivalis can invade host cells, a virulence trait which may contribute to the persistence of infection at subgingival sites. Whilst the antibiotic protection assay has been commonly employed to investigate and quantify P. gingivalis invasion, data obtained have varied widely and a thorough investigation of the factors influencing this is lacking.

Investigation of a Novel Predictive Biomarker Profile for the Outcome of Periodontal Treatment.

Background: An ability to predict the response to conventional non-surgical treatment of a periodontal site would be advantageous. However, biomarkers or tests devised to achieve this have lacked sensitivity. The aim of this study is to assess the ability of a novel combination of biomarkers to predict treatment outcome of patients with chronic periodontitis.

A pilot study of active enzyme levels in gingival crevicular fluid of patients with chronic periodontal disease.

Aim: To determine whether combinations of enzymes in gingival crevicular fluid (GCF) can act as improved biomarkers compared with single enzymes for predicting the outcome of treatment and also for diagnosing the clinical status of sites.

Methods: Thirty subjects with chronic periodontitis were recruited to a 12-month longitudinal pilot study. GCF samples from three representative sites: healthy (≤3 mm), deep non-bleeding (NB) (≥6 mm) and deep bleeding (DB) (≥6 mm) sites and clinical data were collected at baseline, 3 months, 6 months and 12 months following periodontal treatment.

The effects of stress on periodontal treatment: a longitudinal investigation using clinical and biological markers.

Aim: To investigate the effects of psychosocial stress on the outcome of non-surgical periodontal treatment (NPT).

Methods: Patients were categorized as stressed or unstressed, and the degree of stress was measured. One deep bleeding and one deep non-bleeding site ≥6 mm were selected in each patient for detailed investigation, and the clinical parameters were recorded before and at 6 months after NPT.

Acid production and growth by oral Lactobacillus species in vitro.

Aim: To analyze the acid-producing and growth abilities of different oral Lactobacillus species.

Methods: Thirty-nine oral clinical strains and type strains of Lactobacillus, representing nine species, including Lactobacillus casei/paracasei, Lactobacillus fermentum, Lactobacillus gasseri, Lactobacillus mucosae, Lactobacillus oris, Lactobacillus plantarum, Lactobacillus rhamnosus, Lactobacillus salivarius, and Lactobacillus vaginalis were studied. Anaerobically-grown bacterial cells were inoculated overnight in de Man, Rogosa, and Sharpe broth containing 2% glucose (pH 7.

Relationship between the ability of oral streptococci to interact with platelet glycoprotein Ibalpha and with the salivary low-molecular-weight mucin, MG2.

The oral streptococci Streptococcus sanguinis, Streptococcus gordonii and Streptococcus oralis are common aetiological agents of infective endocarditis, and their ability to adhere to and induce the aggregation of platelets is thought to be a virulence trait. The platelet glycoprotein GPIbalpha has been implicated as the adhesion receptor for S. sanguinis and S.

Identification and analysis of a gene (abpA) encoding a major amylase-binding protein in Streptococcus gordonii.

Oral streptococci such as Streptococcus gordonii bind the abundant salivary enzyme alpha-amylase. This interaction may be important in dental plaque formation and metabolism, thus contributing to the initiation and progression of dental caries and periodontal disease, the two most common plaque-mediated diseases. The conjugative transposon Tn916 was used to insertionally inactivate gene(s) essential to the expression of amylase-binding components of S.