Postoperative maxillary cyst (POMC) is a delayed complication many years after surgical intervention of the maxillary sinus. The present study performed histopathological and electron microscopical analyses of POMC in order to clarify the characteristic features associating with its pathogenesis. Histopathologically, various types of epithelial cells lining the cysts were frequently observed. The combination of squamous, columnar or cuboidal epithelium with or without cilia was most major (40 cases, 67%) following by columnar (8 cases, 13%), squamous (7 cases, 12%) and cuboidal epithelium (4 cases, 7%). A case of non-epithelial lining (1%) was also identified. The lamina propria consisted of fibrous connective tissue showing various histopathological changes. Fibrosis, almost including hyalinization, was the most frequent change, 25 cases, 41%, following by mixed changes of fibrosis, inflammatory cell infiltration or edema (24 cases, 40%), inflammatory cell infiltration (7 cases, 12%) and edema (4 cases, 7%). Electron microscopically, the ciliary cells showed 9 + 2 pattern as a typical feature of the respiratory epithelial cells, whereas abnormal features in ciliary cells comprising of absence of central microtubles and irregular arrangement of peripheral microtubles were identified in advance lesions. The basal lamina was swollen and thickened. A tendency of anchoring fibrils to disappear was noticed. Lamina propria consisted of densely accumulation of collagen bundles but sometimes the bundles were sparsely observed. The results suggested that the pathogenesis and growth of POMC had relationship with epithelial degeneration, hyalinization of the lamia propria and thickened basal membrane as regressive changes, edema, retention of the involvements, inflammatory cell infiltration, proliferation and dilatation of the capillary vessels as peripheral circulation disorders, relining and proliferation of the epithelium, squamous metaplasia and fibrosis as progressive changes after surgical operation of maxillary sinusitis as an iatrogenic disorder.

View full abstract

Our previous study has demonstrated that the 40-kDa outer membrane protein of Porphyromonas gingivalis (40k-OMP) nasally administered with a nontoxic chimeric adjuvant that combines the A subunit of mutant cholera toxin E112K with the pentameric B subunit of heat-labile enterotoxin from enterotoxigenic Escherichia coli (mCTA/LTB) elicited a long-term protective immune response. Although using adjuvant mCTA/LTB gave comparable Ab responses in the saliva as using native cholera toxin as adjuvant, the total IgE and 40k-OMP-specific IgE antibodies, as well as IL-4 levels induced by mCTA/LTB were lower than those induced by native cholera toxin. In this study, we further elucidated the nature of 40k-OMP-specific CD4⁺ T helper cells in immunized mice. When CD4⁺ T cells isolated from cervical lymph nodes and spleens of mice immunized with 40k-OMP plus mCTA/LTB as adjuvant were restimulated with 40k-OMP in vitro, significant levels of proliferation occurred in cervical lymph nodes and spleens. Furthermore, mCTA/LTB as adjuvant induced 40k-OMP-specific CD4⁺ T cells secreting INF-γ and IL-4-independent IL-5, IL-6, and IL-10, with IgG2a antibody responses. Analysis of IL-12 receptor expression showed that native cholera toxin, but not the mCTA/LTB, suppressed IL-12 receptor expression by activated T cells. These results suggest that mCTA/LTB as an adjuvant regulates IL-12 receptor expression and subsequent T helper cytokine responses in oral mucosal compartments and that nasal administration of 40k-OMP plus mCTA/LTB is an effective mucosal vaccine against oral infection by P. gingivalis.

View full abstract

It is known that coating a titanium surface with fibronectin or functional domain peptide, Arg-Gly-Asp (RGD), improves initial cell attachment and supports osteoblastic cell differentiation. However, the differences in gene expression in osteoblasts grown on fibronectin-coated titanium (FN-Ti) disks and titanium disks coated with Gly-Arg-Gly-Asp-Ser-Pro (GRGDSP) peptide (GRGDSP-Ti) have not been elucidated. Thus, such coated disks were prepared and MC3T3-E1 osteoblastic cells were cultured on their surfaces. After 15 days, the levels of gene expression in the cells were examined. Most of the expression levels were similar between the two cultures ; however, the mRNA level of otoraplin (OTOR) was significantly greater in cells cultured on the FN-Ti disks compared to those cultured on the GRGDSP-Ti disks. The elevated OTOR mRNA levels were confirmed by reverse transcription-polymerase chain reaction (RT-PCR) and real-time PCR. Because OTOR is known to support cartilage development and maintenance, the elevated gene expression of OTOR in osteoblast precursor cells grown on fibronectin may play a role in osteoblastic differentiation and matrix bone mineralization. Fibronectin possesses the binding domain not only for RGD but also for fibrin, proteoglycan, and collagen, so higher OTOR gene expression may be induced by later ligands. For the future development of biomaterial-modified titanium implants using synthetic peptides, binding domains other than the RGD domain in fibronectin may be useful and important.

View full abstract

Transcutaneous immunization is a novel strategy of vaccination that utilizes a topical application of antigen to intact skin for induction of immune responses. In this study, we have assessed the potential for application of transcutaneous immunization for development of novel vaccine delivery system. When BALB/c mice were immunized with ovalbumin (OVA) by direct application to shaved skin, OVA-specific serum IgG as well as IgA antibody responses were induced. Interestingly, OVA-specific serum IgG responses were higher than those induced by the intraperitonial immunization. Antigen-specific cell proliferative responses confirmed the antibody titers and showed that significantly higher levels of OVA-specific proliferative responses were induced in the CD4⁺ T cells from spleen of mice transcutaneously immunized with OVA when compared with levels induced in CD4⁺ T cells from mice given OVA intraperitonially. Interestingly, while OVA-specific T helper cells from mice immunized intraperitonially produced high IFN-γ with low IL-4 when restimulated with OVA in vitro, transcutaneous immunization resulted in the induction of low IFN-γ with high IL-4 responses. Finally, transcutaneous, but not intraperitonial, immunization with OVA elicited OVA-specific mucosal IgA antibodies in the intestinal tract. These results indicate that transcutaneous immunization may be a better antigen delivery route for induction of antigen-specific antibody responses than parenteral immunization.

View full abstract

The objectives of this study were to clarify the inhibitory effect of relaxin (RLX) on the relapse after expansion of the midpalatal suture in rats, and to assess the expressions of type I collagen and matrix metalloproteinase-1 (MMP-1) using the immunohistochemical and image analysis techniques. Twenty four Wistar male rats (age : six weeks old, body weight : about 200 g) were used in this study. They were divided into the placebo injection group (control group) of 12 rats and the RLX injection group (experimental group) of 12 rats. The expansion period was set to 7 days and the amount of relapse was measured for 14 days. After expansion, immunohistochemical analyses of type I collagen and MMP-1 were performed on 1, 3, 7, 14 days. The amount of expansion was 0.37±0.05 mm in the experimental group and amount of expansion was 0.32±0.08 mm in the control group. The amount of relapse in the experimental group was inhibited about 40% than that of the control group on the 14 days. The type I collagen and MMP-1 showed positive immunoreactivity in the fibroblasts, connective tissues and osteoblasts of the midpalatal suture area. The injection of RLX increased the expression of MMP-1 and decreased that of type I collagen after the expansion of the midpalatal suture, comparing with the control group. The results suggest that RLX may reduce the relapse after expansion of the midpalatal suture through its antifibrotic properties.

View full abstract

The nucleotide sequence of the glucosyltransferase (GTF) gene was determined for the mutans streptococci isolated from the fruit bat oral cavity, Streptococcus dentirousetti NUM1303^T, which encodes a GTF enzyme that synthesizes a water-insoluble glucan. The gtf of S. dentirousetti consisted of a 4,398-bp open reading frame that encoded for a 1,466 amino acid protein and was revealed to belong to the gtfI group. The deduced 38-amino acid sequence of the N-terminal was thought to be a signal peptide for the secretion of GTF-I enzyme, which has high similarity to known GTFs from other streptococci, and three major functional domains of GTFs : an N-terminal variable region, a conserved catalytic site for the hydrolysis of sucrose, and C-terminal repeating units for glucan binding. The percent homology of the amino acid sequence of the GTF-I from S. dentirousetti and Streptococcus orisuis is 99%, however, this score shows 78% when compared to Streptococcus sobrinus. Phylogenetic analysis suggested that this gtfI was closely related to Streptococcus orisuis based on the amino acid sequences from the other related streptococcal GTFs.

View full abstract

Triamcinolone acetonide has been effectively used in the treatment of oral ulcers. This report discusses the cytological findings of two cases of non-specific ulcerated lesions in which there were cytological changes to epithelial cells from the application of topical triamcinolone acetonide for more than 1 month with no favorable outcome. However, the outcome was successful when the two patients were told to discontinue using the paste. It is the purpose of this report to document the presence of associated side reactions following the topical usage of this paste, emphasizing that triamcinolone acetonide should be administered only after it has been determined cytologically that the lesion is free from Candida or fungal infection and atypical cells.

View full abstract