Oral infection control to assist infliximab therapy in a Behçet's disease patient with severe eye inflammation in response to dental treatment: a case report.

KEY CLINICAL MESSAGE: We report a case of Behçet's disease which was aggravated by psychological stress and oral infection. The control of oral infection under medical and dental collaboration is important for providing Behçet's disease patients with the optimal medical care and for facilitating the relief of the primary disease.

Highly expressed genes in a rough-colony-forming phenotype of Aggregatibacter actinomycetemcomitans: implication of a mip-like gene for the invasion of host tissue.

Aggregatibacter actinomycetemcomitans, a potent pathogen of periodontitis, typically grows as a rough and adherent colony on primary isolated cultures. The colony transforms into a smooth phenotype during repeated subculture. In this study, we aimed to identify highly expressed genes in the rough-colony-forming phenotype for isolation of host-induced genes. Using a cDNA-subtractive hybridization technique, three genes, homologous to a macrophage infectivity potentiator gene (mip), peroxiredoxin gene (prx) and outer membrane protein gene (ompA), were identified. The expression levels of these genes in the rough-colony-forming phenotype were 4-10-fold higher as compared with the smooth-colony-forming phenotype. Attention was focused on the mip-like gene, and a recombinant protein and a deficient mutant were constructed. The recombinant protein reacted with sera from patients with periodontitis, suggesting the production of the Mip-like protein in periodontal lesions. Viable quantitative invasion assay demonstrated that the viable cell counts of the wild-type strain that invaded HeLa cells were more than fourfold as compared with the mip-deficient mutant. The expression of the mip-like gene, prx-like gene and ompA-like gene may be enhanced in the host, and the mip-like gene may play an important role in the infection of A. actinomycetemcomitans, especially in its invasion of the epithelium.

Appearance of multidrug-resistant opportunistic bacteria on the gingiva during leukemia treatment.

BACKGROUND: Dentists generally recognize the importance of periodontal treatment in patients with leukemia, with the most attention paid to preventing the development of odontogenic infection. For physicians, the worst type of infection is one caused by multidrug-resistant bacteria. Here, we report a patient with an abnormal increase in multidrug-resistant opportunistic bacteria in the gingiva during hematopoietic cell transplantation (HCT). METHODS: A 53-year-old woman receiving HCT for leukemia had an insufficient blood cell count for invasive periodontal treatment before HCT. Even brushing caused difficulties with hemostasis. Therefore, frequent pocket irrigation and local minocycline administration were performed. RESULTS: The multidrug-resistant opportunistic bacterium Stenotrophomonas maltophilia was detected first in phlegm 2 days before HCT, and it was detected in a gingival smear and a blood sample 7 and 11 days after HCT, respectively. The patient developed sepsis on day 11 and died 14 days after HCT. Frequent irrigation and local antibiotic application were ineffective against S. maltophilia on the gingiva. Inflammatory gingiva without scaling and root planing showed bleeding tendency, and this interfered with the eradication of this bacterium. CONCLUSIONS: The gingiva in patients undergoing leukemia treatment acts as sites of proliferation and reservoirs for multidrug-resistant opportunistic bacteria. Severe systemic infection by multidrug-resistant bacteria in such patients with leukemia also may involve the gingiva. To prevent abnormal increases in such bacteria on the gingiva, scaling and/or root planing before chemotherapy, which reduces bleeding on brushing during the neutropenic period caused by chemotherapy, may contribute to infection control in such patients, although it was impossible in this case.

Periodontal treatment in severe aplastic anemia.

BACKGROUND: Aplastic anemia (AA) is a rare hematologic disease characterized by hypo-cellular bone marrow. The clinical features include fatigue, increased bruising, and gingival bleeding caused by anemia, leukopenia, and thrombocytopenia. A patient with AA is at high risk for infection because of leukopenia. The risk of systemic infection is especially high in AA patients with severe local infections, including periodontitis. Accordingly, periodontal treatment should include antibiotic prophylaxis to reduce the risk of systemic infection. However, treatment of periodontitis in the AA patient is significantly complicated by the bleeding disorder. We present a case report of the successful periodontal treatment of an AA patient with spontaneous gingival bleeding. METHODS: The patient was closely monitored for platelet and neutrophil counts before every treatment. The patient's platelet count was always under 10,000/microl. Therefore, it was necessary to increase platelet counts to over 25,000/microl by transfusion, after which subgingival scaling with anesthesia was performed. When the neutrophil count was less than 2,000/microl, local minocycline chemotherapy was applied to the pockets. Periodontal infection was monitored by detection of bacterial DNA and measurement of serum immunoglobulin (Ig) G titer against periodontal bacteria. RESULTS: Following the physical and chemical treatment, the gingival appearance improved dramatically and the spontaneous gingival bleeding disappeared. Moreover, the IgG titer against periodontal bacteria decreased to normal range and specific periodontal pathogens were no longer detectable in the tested pockets. CONCLUSION: We believe that the treatment strategy in the present report provides new sight into treatment planning for severely medically compromised patients.

Transcriptional regulation of beta-defensin-2 by lipopolysaccharide in cultured human cervical carcinoma (HeLa) cells.

Human beta-defensin-2 (hBD-2) is an antimicrobial peptide with a broad spectrum of antimicrobial activity against bacteria, yeast and fungi. Here, we analyzed the transcriptional regulation of hBD-2 in cultured human cervical carcinoma (HeLa) cells with or without lipopolysaccharide (LPS). DNA from position -329 to -39 in the hBD-2 promoter region contained the consensus binding sites for transcription factors, one site for nuclear factor for IL-6 expression (NF-IL6) and two sites for nuclear factor-(kappa)B (NF-(kappa)B). Reporter gene assays for promoter activity revealed that the region had the highest level of responsiveness to LPS. Furthermore, mutations in both of the NF-(kappa)B binding sites caused a significant reduction of the responsiveness to LPS, whereas mutation in the NF-IL6 binding site resulted in an elevation of the basal promoter activity. Electrophoretic mobility shift assays demonstrated that LPS induced the binding of HeLa nuclear factors to 60-bp probe containing the two NF-(kappa)B binding sites, suggesting that the sites were essential for the binding. Our results suggest that the two NF-(kappa)B binding sites contribute to LPS-mediated hBD-2 transcription while the NF-IL6 binding site represses LPS-independent hBD-2 transcription in the HeLa cells.

Systemic up-regulation of sTNFR2 and IL-6 in Porphyromonas gingivalis pneumonia in mice.

Aspiration pneumonia is a common cause of death in older people, and the pathophysiology is a chronic respiratory failure with a mild airway inflammation. In this study, we established a mild inflammatory pneumonia model using Porphyromonas gingivalis (Pg) pathogen-infected mice. It elucidated the effects of Pg-infected pneumonia on proinflammatory cytokines tumor necrosis factor (TNF)-alpha, interleukin-6 (IL-6), and IL-1beta production in both lung tissue and serum. We also elucidated production of soluble (s) TNF receptor (R) s, because TNF-alpha is considered to be a dominant inflammatory mediator. Lung TNF-alpha levels significantly increased at 2 h after infection, and rapidly returned to basal level at 24 h. Consistent with increase of TNF-alpha, remarkable increase of sTNFR2 but not sTNFR1 was detected in lung tissue from 2 to 72 h. Interestingly, sTNFR2/sTNFR1 ratio was significantly enhanced at 2 h in serum. In addition, lung IL-1beta and IL-6 levels also significantly increased from 2 to 24 h. Importantly, we found that IL-6 levels in serum reflected its local level. These results may suggest that systemically produced sTNFR2 and IL-6 could be a key role to modulate proinflammatory activities of TNF-alpha in Pg-induced lung inflammation simulated aspiration pneumonia.

Antibacterial activity of synthetic human B defensin-2 against periodontal bacteria.

The oral epithelium is continuously exposed to a variety of microbial challenges that can cause infectious diseases such as periodontal disease. Human B Defensin-2 (hBD-2) is a cationic antimicrobial peptide with low molecular weight, which is inducible from oral epithelial cells upon either bacterial infection or stimulation with inflammatory cytokines. This peptide has a broad antimicrobial spectrum that includes gram-positive bacteria, gram-negative bacteria, and fungi. Therefore, it is thought that hBD-2 plays an important role as one of natural immunities to bacterial infection. However, its activity is inhibited by body fluids such as serum. The aim of this study was to assess the antibacterial activity of synthetic hBD-2 against oral bacteria in the presence of saliva or serum. The antibacterial activity of synthetic hBD-2 was tested against Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, Streptococcus mutans, and Escherichia coli. Antibacterial broth assay and diffusion assay were performed in vitro. The antibacterial activity of hBD-2 was approximately equal to that of minocycline at equimolar concentrations. Furthermore, the activity of hBD-2 remained at 60% in the presence of 80% saliva, whereas no activity remained in the presence of 20% serum. Our results suggest the possibility that synthetic hBD-2 could be useful to prevent infection by periodontal bacteria.

Periodontal disease and diabetes mellitus: the role of tumor necrosis factor-alpha in a 2-way relationship.

It is generally accepted that obesity is associated with many other multiple-risk factor syndromes such as hypertension, hyperlipidemia, type 2 diabetes mellitus, and periodontal disease. The number of obese people is increasing rapidly in both western and eastern countries. Adipocytes in the adipose tissues of obese people produce large quantities of biologically active molecules such as leptin, an important molecule regulating energy expenditure and body weight. Therefore, adipocyte-derived active molecules, named adipocytokines, are candidate molecules accounting for the close association between obesity and other multiple-risk factor syndromes. The proinflammatory cytokine tumor necrosis factor-alpha (TNF-alpha) is produced by adipocytes, and its blood concentration is elevated in obese patients and declines with weight loss. Studies have demonstrated that TNF-alpha suppresses insulin action via its specific receptor; hence, it exacerbates insulin resistance. In addition to adipocytes, monocytes/macrophages produce large quantities of TNF-alpha. Thus, TNF-alpha, produced from monocytic cells due to inflammatory diseases, may have an additive influence on insulin sensitivity to adipocyte-derived TNF-alpha. Here, we hypothesized that 1) TNF-alpha produced by the adipose tissues of obese patients acts as a risk factor for periodontal inflammation, and 2) TNF-alpha produced due to periodontal inflammation may be an additional important factor influencing insulin sensitivity in both obese and type 2 diabetic patients. We believe that this interaction is a possible mechanism accounting for a 2-way relationship between type 2 diabetes and periodontal disease.