Mucosal immunization would provide an easy and safe measure in preventing infectious diseases by facilitating mass immunization. In order to represent a promising strategy for mucosal vaccination, oral, nasal, or sublingual immunizations of mice with a recombinant 40-kDa outer membrane protein of Porphyromonas gingivalis (r40k-OMP) and cholera toxin (CT) as a mucosal adjuvant were performed, and mucosal and systemic immune responses were compared. Administration of the antigen via the mucosal routes, such as orally, nasally or sublingually, equally elicited significant levels of r40k-OMP-specific IgG in the serum and high numbers of r40k-OMP-specific antibody-forming cells (AFCs) in the spleen. Nasal and sublingual immunization of mice also induced high levels of mucosal IgA antibodies (Abs) in the saliva and nasal washes compared to oral immunization. Subsequently, these immunizations confirmed the Ab titers by revealing significant numbers of r40k-OMP-specific AFCs in the submandibular glands, nasopharyngealassociated lymphoreticular tissue, and nasal passages. In contrast, mice that were orally immunized with r40k-OMP plus CT exhibited significantly increased antibody secreting cells in Peyerʼs patches and intestinal lamina propria, although lower level of cells were detected in nasal or sublingual immunization. These results have suggested that both nasal and sublingual immunization are more effective for prevention of periodontal disease compared to oral immunization.

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Growth of the craniofacial bone is a complex biological phenomenon induced by highly coordinated interaction between genetic and environmental factors. The purpose of this study was to confirm whether the environmental factors, namely powdered diet and extraction of all upper molars, have an influence on the cranium and mandibular bone size,bone volume, mineral bone density, widths between left and right condyles and gonions,and intra-arch widths at the first and third molars in rat mandibles.
Ten 5-week-old male Wister rats were fed on powdered diet after extraction of all upper molars (experimental group=5 rats) and pellet diet without extraction of molars (control group=5 rats) for 20 weeks. At 20 weeks of age, the animals were examined by Microcomputer tomography. The mean values of the measurements in the two groups were compared.
There was no significant difference between the groups in the cranial sizes. The vertical lengths were significantly shorter in the experiment group than the control group while no significant difference was observed in the mandibular horizontal lengths and widths at the left and right condyles and gonions. The mandibular volume and bone mineral density in the experimental group were significantly lower than that of the control group. The intraarch width at the lower third molars was also significantly shorter in the experimental group than the control group.

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The purpose of this study was to develop a Japanese questionnaire for subjective oral dryness and revealfactors associated with xerostomia among Japanese youth. A sample of 237 male and 144 female Japanese students (mean age: 20.8 years) was selected. The validity of the questionnaire was assessed through factor analysis, while its reliability and internal consistency were assessed with Cronbachʼs alpha. The impact of health, daily life,food intake, and oraldryness on xerostomia was assessed. To this end, subjects responded to questions on oral dryness, health, daily life, and food intake; unstimulated saliva was also collected from the subjects. Unstimulated salivary flow rate ranged from 0.02 to 1.8 ml/min (mean: 0.32ml/min.). Factor analysis revealed that the questionnaire comprised 12 items making up four factors, namely,"at swallowing the food particle," "oraldryness during mastication," "dryness of the lips or facial surface," and "dryness at night." All factors had a Cronbachʼs alpha of 0.6 or more. In addition, subjects with an unbalanced diet had a threefold susceptibility to xerostomia.
The questionnaire is deemed a valid and reliable measure of subjective oral dryness among Japanese youth. By using this questionnaire, the relationship between xerostomia and a self-reported unbalanced diet was suggested.

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Purpose: The difference in salivary flow rates between non-removable partial denture (RPD) wearers and regular RPD wearers is not well investigated. The purpose of this study was to examine the change in salivary flow rate after the insertion of dentures in elderly patients, especially for those with a shortened dental arch (SDA). Factors associated with the changes were also investigated. Subjective measures of oral dryness were also assessed to investigate changes in the amount of individual salivary flow associated with denture usage.
Methods: Fifty-five participants were enrolled, including subjects not wearing dentures (ND: n=21) and subjects wearing dentures (WD: n=33) at the commencement of the study. Unstimulated saliva (US) and stimulated saliva (SS) were collected at baseline and at the 1-month follow up. Follow-up was performed 1 month after insertion for ND subjects,and 1 month after baseline measurements for WD subjects. Maximal occlusal force and an oral dryness questionnaire were administered at baseline and follow-up.
Results: ND subjects showed significantly lower US values at baseline (ND: 0.04 mL/min,WD: 0.12 mL/min, p=0.007). At follow-up, no significant difference in US was observed between the groups (WD: 0.10 mL/min, ND: 0.08 mL/min, p=0.57). At follow-up,salivary flow rate and subjective measures improved in the ND group.
Conclusions: Patients without RPDs had lower salivary flow rates than those wearing dentures. Increases in US flow rate and improvements in subjective oral dryness were observed after denture insertion.

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Midazolam（MDZ）is reported to have immunomodulatory properties that affect immune cells. However, little is known about the effects of MDZ treatment on Immunoglobulin（Ig）E responses. Therefore, we examined whether MDZ is able to suppress total IgE production, followed by IgE class switch recombination（CSR）, in a mouse model. To assess the effects of MDZ on IgE-CSR, splenic B cells were cultured with LPS, IL-4 and anti-CD40 antibody in the presence or absence of MDZ for 72 h. Total-IgE, interferon-gamma（IFN-γ）responses and surface IgE-positive（sIgE⁺）B cells were analyzed by ELISA and flow cytometry. To confirm IgE-CSR, total RNA was isolated from splenic B cells and levels of CSR-associated molecules, such as germ-line transcript ε（εGLT）, germ-circle transcript ε（εCT）, activation-induced cytidine deaminase（AID）and inhibitor of differentiation 2（Id2） were compared. MDZ significantly decreased total IgE production and numbers of sIgE⁺ B cells. Significantly reduced levels of both εGLT- and εCT-specific mRNA were detected in MDZ-treated B cells. In contrast, Id2-specific mRNA transcript, which is a negative regulator for Ig-CSR, was increased on MDZ-treated B cells. Furthermore, MDZ-treated B cell significantly increased IFN-γ production and IFN-γRα expression. These results suggest that MDZ inhibits εGLT and εCT expression, and IgE synthesis via induction of IFN-γ production. MDZ may be useful for preventing IgE-mediated allergic diseases.

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A narrowed maxillary dental arch can be treated by laterally expanding either the maxillary arch or maxillary bone with a RME appliance. But, the effects of RME on maxillary and mandibular dental arches, palatal morphology, and oral function have not been sufficiently clarified. Therefore, to investigate if differences in palatal morphology affect changes brought about by maxillary expansion, we examined post-expansion changes in maxillary and mandibular dental arches and palatal morphology. We also examined the direction of the width of mastication pathway and tongue elevation pressure. The study was composed of 12 pediatric patients; they were treated using a rapid maxillary expansion appliance. Maxillary and mandibular dental models, width of mastication pathway, and tongue elevation pressure were taken at T1, T2, and T3 ; lateral cephalograms were also taken at T1. Dental model measurement results indicated greater palatal width and lower palatal height in G1 than those in G2. Lateral cephalograms indicated significant differences between G1 and G2 for the gonial angle, Frankfort mandibular plane angle, lower facial height, and occlusal plane. The above findings revealed that the rapid expansion stage for RME varies according to palatal morphology: in patients with rectangular dental arches, expansion occurred mainly in the palatal base area,whereas in patients with high palates, expansion occurred mainly in the shallow palatal areas. In addition, we found that width of mastication pathway, tongue elevation pressure,lower molar dental arch width, and lower tooth bucco-lingual inclination increased in patients with rectangular dental arches.

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Oral candidiasis presents characteristic histopathological findings. The mucous epithelium at the site of candidiasis is covered by a hyperkeratinized layer. But, the factors leading to hyperkeratosis in candidiasis were unknown. To investigate the factors which led to hyperkeratosis in oral candidiasis, we histopathologicaly, histochemicaly, and ultrastructualy observed the morphological alteration of the epithelial tissue, and studied the factors in connection with those changes immunohistochemically.
Candidiasis group (8 cases of papilloma, 5 cases of verrucous hyperplasia), non-candidiasis group (8 cases of papilloma, 7 cases of verrucous hyperplasia), and 5 subjects with normal oral mucosa were selected. Ultrastructually, Candidal hyphe internalized into the epithelial cytoplasmic vacuole resembling endocytosis.Destruction of desmosomal cell junction and deficit of tonofilament was also observed at the tip of the hypha. Immunohistochemistry,weaker expression for E-cadherin was seen in the candidiasis group. Strong positive Ecadherin reaction was seen along the insertion sites of the hyphae. CK13 was negative in non-candidiasis group, and weakly positive in candidiasis groups in the basal layer,respectively. Weakly positive EGFR reactions were observed in the prickle layer in candidiasis group. Inflammatory reaction with NE, CD68, COX-2, CD105 and Ki-67 were markedly observed in candidiasis group.
The above result suggested that the hyperkeratosis in oral candidiasis was related with Ecadherin in connection with adhesion and penetration of Candidal hyphae and the precocious expression of the stratified squamous epithelium later differentiated marker CK13. Furthermore, it was surmised that inflammatory response by Candidal hyphae invasion itself led to hyperkeratosis.

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To clarify the process to squamous metaplasia, we investigated ultrastructural features of the salivary ducts. And immunohistochemical staining was performed to determine the expression of cytoskeletal and intercellular adhesion molecules associated with morphological alterations of the salivary ducts. This study comprised 117 patients with chronic sialadenitis. The salivary ducts of the patients were microscopically classified into the following three groups: dilated ducts; hyperplastic ducts; and squamous metaplastic ducts. Squamous metaplastic ducts occurred in 34 of the 117 patients (29.0%). Immunohistochemical staining was performed in 25 patients with sialadenitis in whom the histological specimens were not decalcified at the time of preparation. Histopathological and ultrastructural analyses of the hyperplastic ducts showed hyperplasia of cuboidal basal cell-like cells with relatively high nucleus/cytoplasmic ratio. Immunohistochemically,hyperplastic basal cell-like cells were positive for p63, CK34βE12, CK5/6, CK19, and Ecadherin, thus reflecting basal cell characteristics. In immature squamous metaplastic ducts, positive reaction for CK18, CK5/6 and E-cadherin were attenuated. In mature squamous metaplastic ducts, CK13 appeared instead of E-cadherin and β-catenin. This study showed that dilation of ducts was due to abnormal physical irritation and that chronic irritation causes basal cell hyperplasia as a biological adaptive response. Basal cell hyperplasia and squamous epithelium characteristics were also demonstrated by ultrastructural analysis by using electron microscopy. These changes are also supported by the fact that cytokeratin in ductal epithelial cells undergo transition from a glandular epithelial type to mucosal type. These results suggest that basal cell hyperplasia is a squamous metaplastic process.

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Bone sialoprotein (BSP) is a prominent mineral-associated protein in the extracellular matrix of bone that has been implicated in the metastatic activity of cancer cells. Forskolin (FSK) is a labdanediterpene that is produced by the Indian Coleus plant. FSK elevates cyclic AMP (cAMP) via adenylate cyclase activated protein kinase A (PKA), and it is widely used to study cAMP regulation of cell processes.
Here, it is reported how FSK regulates BSP gene transcription in human breast cancer MCF7 cells. FSK (1 μM) increased BSP, Runx2 and Osterix mRNA levels in MCF7 cells at 12 h. From transient transfection analyses using various BSP promoter-luciferase constructs, a cAMP response element (CRE), a runt homeodomain protein 2 (Runx2) and a fibroblast growth factor 2 (FGF2) response element (FRE) were identified as a target of transcriptional activation by FSK. Gel mobility shift analyses showed that FSK increased binding of CRE and FRE. These studies demonstrate that FSK stimulates BSP transcription in MCF7 cells by targeting the CRE and FRE elements in the BSP gene promoter.

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Sarcomas usually occur in young individuals. We report a case of rhabdomyosarcoma occurring in a 28-year-old man who presented with a 5-month history of episodic pain in the right mandible. This case is significant because very few cases of this entity in the jaw have been reported in young individuals. Surgery along with radiation and chemotherapy proved successful in treating this case. Long-term follow-upis needed in such unusual cases to clarify treatment outcomes.

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