I investigated the effect of glucocorticoids on the expression and localization of basic fibroblast growth factor(bFGF) during wound healing. Six-week-old male Wistar rats were injected subcutaneously with prednisolone for 4 weeks in the experimental model. The tongue was incised with a knife to full thickness and the healing process were observed histologically, immunohistologically and by the reverse transcription-polymerasechain reaction(RT-PCR) for 10 days after the operation. Compared with the controls, the experimental animals showed infiltration of inflammatory cells and inhibition of granulation tissue formation. The immunoreactivity of bFGF became weaker and bFGFmRNA expression, by RT-PCR, was delayed and weakened. These results indicate that glucocorticoids suppressed bFGF expression during the repair process, resulting in inhibition of angiogenesis and fibrogenesis, and a delay in the healing process. Shika Igaku (J Osaka Odontl Soc) 1997 Dec； 60(4)：241-255．

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Diabetes mellitus obstructs bone metabolism throughout the body. Although diabetes delays osseous healing, its effect on bone trabeculation during the healing process is still unclear. Six-week-old male Wistar rats were divided into a diabetic group injected with streptozotocin and a control group injected with buffer. Bone defects were produced in the mandible at 22 weeks of age. Osseous healing was analysed by confocal laser scanning microscopy(CLSM) to study the process of dimensional mineralization.
After one month, light microscopy indicated completion of osseous healing in the controls, but not in the diabetic group. CLSM indicated that the mineralization front for both groups was labeled from the bottom toward the margin of the cavity over time. However, this process was delayed in the diabetic group. With regard to bone trabeculation, mineralized labelling of the control group showed increased connectivity in the trabeculae. Three-dimensional images of the trabeculae in the diabetic group demonstrated deteriorated connectivity compared with the controls.
These results indicate that diabetes not only delays initial bone formation, but also inhibits bone maturation, suggesting a low turnover in bone metabolism. Shika Igaku (J Osaka Odontl Soc) 1997 Dec； 60(4)：256-272．

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We evaluated the cellular reactions to ten chemicals including components of dental cements by examining stress protein synthesis and cell viability with neutral red(NR) and 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyl tetrazolium bromide (MTT). Induction of 70, 000-Da stress protein (HSP 70) synthesis in HeLa cells by chemicals was evaluated by an enhanced chemiluminescence system.
HSP 70 synthesis was induced during the early stage between three and six hours of exposure to phosphoric acid, methyl methacrylate monomer(MMA), formalin and hydrochloric acid at concentrations of 50 to 500μM. Acrylamide induced HSP 70 to a small extent, while the other agents examined, i.e. eugenol, itaconic acid, chloroform, acetone and xylene, had no effect. The results of NR and MTT assays revealed that phosphoric acid, eugenol, itaconic acid, formalin, hydrochloric acid and acrylamide at concentrations of 500μM and over, inhibited the cells, while MMA, chloroform, acetone and xylene did not.
It was concluded that the synthesis of HSP 70 might represent a cellular change caused by acidic chemicals, and that the concentration that induced HSP 70 synthesis was lower than that inhibiting cell viability. Shika Igaku (J Osaka Odontol Soc) 1997 Dec；　60（4）：273-287．

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We studied the effect of a mouthwash containing a bacterial enzyme derived from Streptomyces globisporus strain 1829 on the initial stage of plaque formation. The surfaces of celluloid coatings that had been placed on teeth in the oral cavity were stained with a methylene blue stain, and the results analyzed with a scanning electron microscope, Photo Pattern Analyzer, and X-Y recorder. The findings suggested that this mouthwash inhibited the initial stage of plaque formation. Shika Igaku (J Osaka Odontol Soc) 1997 Dec ； 60(4)：288-301．

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We compared aspects of the ramification of the external carotid artery system in Chinese, which were preserved in the Department of Anatomy, First Military Medical University, Guangzhou, China, with those of Japanese. We observed 7 arteries on 31 sides of 17 Chinese. They included the superior thyroid, lingual, facial, occipital, posterior auricular, superficial temporal, and maxillary arteries. Four arteries, the superior thyroid, lingual, facial, and occipital, showed variations that included alteration of the ramification order and formation of a common trunk by two arteries. However, the posterior auricular, superficial temporal, and maxillary arteies showed ramification without variation. The mean length of the external carotid artery in the Chinese was 64.5 mm.The aspects of ramification could be classified into 8 types, which were essentially the same for Chinese and Japanese. Shika Igaku (J Osaka Odontol Soc) 1997 Dec ； 60(4)：302-308．

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We examined the relationship between tight junctional permeability and the sealing mechanism of adhesive molecules in rat submandibular gland cells. The intensity and pattern of E-cadherin expression in the glands were investigated using immunocytochemical staining. At the same time, permeability of the tight junctions was tested using microperoxidase as a tracer.
In the control glands, there was strong expression of E-cadherin molecules on the cell-cell boundaries in acinar cells, and the tight junctions were impermeable to microperoxidase. Cadherins are transmembranous calcium dependent cell-cell adhesion receptors in vertebrates that connect cells via homophilic interactions. We found that even when only a small volume of fluid was injected intraductally into the submandibular gland, some passed into the extracellular spaces of the gland via the tight junctions. E-cadherin expression was reduced after the glands were intraductally injected with anti E-cadherin monoclonal antibody dissolved in saline. In this case, the tight junctions became permeable to microperoxidase. These results indicate that E-cadherin plays a major role in mediating intercellular physical adhesion and tight junctional permeability. Shika Igaku (J Osaka Odontol Soc) 1997 Dec； 60(4)：309-315．

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