Catalase expression of Propionibacterium acnes may contribute to intracellular persistence of the bacterium in sinus macrophages of lymph nodes affected by sarcoidosis

Immunologic Research - Bacterial catalase is important for intracellular survival of the bacteria. This protein of Propionibacterium acnes, one of possible causes of sarcoidosis, induces...     

Antimicrobial action of natural substances on oral bacteria

The antimicrobial action of natural substances was investigated in vitro against oral bacteria including Streptococcus sp., Actinomyces sp., Actinobacillus sp., Bacteroides sp., Capnocytophaga sp., Eikenella sp., Fusobacterium sp. and Propionibacterium sp. Among the natural substances tested, hinokitiol was the most inhibitory to oral bacteria. Cinnamon bark oil, papua-mace extracts, and clove bud oil in spice extracts were also inhibitory against many oral bacteria. Egg white lysozyme exhibited antimicrobial action against the periodontitis associated bacteria.     

Clinical application of a new compact CT system to assess 3-D images for the preoperative treatment planning of implants in the posterior mandible A case report

When treatment planning before placing dental implants in the posterior region of the mandible, the locations of the inferior alveolar nerve and mental foramen need to be ascertained, as they determine the bone height available and the implant length selected. The purpose of this study was to introduce the clinical application of a newly developed compact computed tomography system (Ortho-CT) to assess three-dimensional (3-D) images for the preoperative treatment planning of implants in the posterior region of the mandible. To evaluate the 3-D images, we scanned using the Ortho-CT system the mandible with a radiopaque template placed in the posterior region. The Ortho-CT images provided excellent information for evaluating the morphology of the mandible, and for showing the location of the inferior alveolar nerve, mental foramen and the relationship of the template to the bone. We consider that Ortho-CT is a useful aid to preoperative treatment planning of implant therapy in the mandible.     

Bacterial adherence to gingival epithelial cells of rats with naturally occurring gingivitis

Bacterial adherence to gingival cells was compared in rats with spontaneous gingivitis (SUS rat) and in control rats (RES rat). In the SUS rat, the number of adherent bacteria in gingival cells changed according to the progression of gingival inflammation. There was a correlation between the change of the number of adherent bacteria, progress of inflammation and pH in the pocket. In the RES rat, the number of adherent bacteria was constant and very small. In the adherence assay, adherence of Bacteroides intermedius to epithelial cells was dependent on the pH. Adherence of B. intermedius was better than that of other species. B. gingivalis and B. macacae showed good adherence but B. levii showed poor adherence. Adherence to the epithelial cells of the SUS rat was always better than that of the RES rat. These results were supported by scanning electron microscopic studies.     

Immunodominant region of Actinobacillus actinomycetemcomitans 40-kilodalton heat shock protein in patients with rheumatoid arthritis

Bacterial heat shock proteins have been implicated in the pathogenesis of several diseases, and the immunological relationship between rheumatoid arthritis (RA) and Escherichia coli DnaJ has been reported. Since there are similarities in the tissue destruction process of RA and periodontitis, we examined the reactivities of antibodies in sera from RA patients to the DnaJ protein from Actinobacillus actinomycetemcomitans. An enzyme-linked immunosorbent assay showed that IgG titers to the N-terminal conservative region of the DnaJ are significantly higher in RA patients compared with the healthy controls (p < 0.05). Furthermore, we examined IgG titers of disease controls to determine the specificity of the immune responses to this region in RA patients. The difference between RA and infectious disease patients was also significant (p < 0.05). These results suggest that the N-terminal region of DnaJ from A. actinomycetemcomitans may contribute to the etiologic analysis of RA.     

Salivary spinability and periodontal disease progression in an elderly population

OBJECTIVE: To explore the relationship between the spinability of stimulated whole saliva and periodontal disease progression over 12 months in an elderly population. METHODS: Three hundred and thirty-two subjects aged 76 years at baseline were studied. Attachment loss was calculated on a site-by-site basis, and periodontal disease progression was defined as an attachment loss of >/=3mm. Stimulated whole saliva was collected and salivary spinability (SS) was measured. A multiple linear regression analysis was performed to assess the relationship between periodontal disease progression and SS after controlling for other covariates. The independent variables were selected from those which had significant relationships with disease progression in the bivariate analyses. RESULTS: Mean SS was 1.94+/-0.42mm in males and 1.88+/-0.32mm in females; this difference was not significant. Simple linear regression analysis showed a significant positive relationship between periodontal disease progression and SS (P=0.026), whereas there was no significant relationship between periodontal disease progression and salivary flow rate. Multiple regression analysis revealed a significant positive relationship between periodontal disease progression and SS (P=0.024) after controlling for the number of remaining teeth and baseline periodontal conditions. The model explained 15.5% of the variance in the percentage of sites where the disease had progressed. CONCLUSIONS: These findings suggest that elderly subjects with viscous saliva are prone to periodontal disease progression.