Aspects of the ultrastructure of major salivary glands of mammals are reviewed with special attention to the variations manifested by different species. The species- specificity of secretory granules is shown as well as specialized cytoplasmic structures in endpiece secretory cells. Granular convoluted tubule cells in Praomys natalensis, the richest known source of nerve growth factor, are illustrated, as well as the structural basis for basal striations in striated ducts. Different kinds of crystalloids occurring in excretory ducts are displayed. An extreme departure from conventional salivary gland histology is demonstrated. Finally, a situation in which the lumina in the accessory submandibular gland of an exotic bat are occupied by an abundance of bacteria, which are thought to be symbiotic, is illustrated.

View full abstract

Serotoninergic neuron located at peripheral sites is thought to be concerned as an one of the pivotal factor of the tissue inflammation which leads to pain behavior. However, which serotonin (5-HT) receptor subtypes is involved in peripheral sensitization is not understood. Sarpogrelate HCl (MCI) is a novel compound which may modulate inflammatory reaction through 5-HT_<2A> receptor antagonism. No data have still been examined the effect of MCI on inflammatory pain response in relation to spinal glutamate (CSF-Glu) release and that whether this effect is affected to 5-HT_<2A> receptor or not. The present study was designed to evaluate the modulating effect of local administration of MCI on the instances of flinching behavior and CSF-Glu after 5-HT injection into the rat paw. Three days after intrathecal implantation of loop-type microdialysis probe in male Sprague-Dawley rats, 100μl of 0.12% 5-HT was subcutaneously injected into left hind paw. Thereafter, simultaneous determinations of microdialysis at 10min. -intervals for glutamate by HPLC-ECD and observation of flinches were performed for 30 min after subcutaneous administration of either drugs (saline for control, MCI, MCI+α-methyl-5-HT) Flinching behavior after injection of 5-HT in saline groupe were observed (max. 22 flinches/min. at 1-2 min). CSF-glu in saline groupe increased by 124% during the first 10 min. MCI in a dose of 5μg given s. c. attenuated both flinching / min and CSF-glu. But those effects were antagonized by giving a-methyl-5-HT, 5μg. Based on the present study, MCI admistration provokes antinociceptive effect on 5-HT-produced inflammatory pain behaviour in relation to CSF-Glu. These effects were reversed by 5-HT_<2A> receptor agonist, suggesting MCI has a beneficial effect on hyperalgesia via inhibiting selective 5-HT_<2A> receptor and CSF-Glu release.

View full abstract

The purpose of this study is to clarify the relationship between MRI findings and clinical symptoms in temporomandibular joint disorders. There were 78 temporomandibular joint (TMJs) from 39 patients : Males (4 or 10%) and females (35 or 90%). The youngest subject was an 11-year-old girl and the oldest subject was a 69-year-old female. The average was 30.8 years. MRI of the TMJ was obtained by a SMT-100X type (1.0T) (Shimazu Co., Kyoto, Japan) using a surface coil with a diameter of 11.5cm. A proton density weighted image (TR=1500 msec, TE=22 msec) was selected for the sequence. Sagittal planes of the TMJ in closed and open mouths and coronal planes in closed mouths were obtained. Each plane had a 3 mm thickness and a 1 mm interval. The results obtained were as follows : 1. Of the 39 patients, 19 (49%) showed a limited mouth opening as a clinical symptom. Whereas, 18 (46%) had a clicking noise on the TMJ upon opening the mouth. Four of those 18 had pain accompanied on the bilateral TMJs. Of the remaining 14, eight had the clicking noise without pain on the unilateral TMJ of the right side and the other six on the left side. 2. Of the 78 TMJs, 34 (44%) had a normal disc position and 44 (56%) had an anterior disc displacement in closed mouths. Among the 34, there was a reduction of the disc in open mouths. Of the 44, there was a reduction of the disc in open mouths among 29 (66%). However, in the other 15 (34%) there was no reduction of the disc in open mouths. 3. Of the 78 TMJs in closed mouths, 52 (67%), located on top of the mandibular condyle, showed a normal disc position. Of the remaining TMJs, 12 (15%) showed medial disc displacement and 14 (18%) showed lateral disc displacement. Of those 12, six (50%) were accompanied by anterior disc displacement. Of the 14, ten (71%) were accompanied by anterior disc displacement. 4. Of the 19 subjects, representing 38 TMJs, those with a chief complaint of limited mouth openings, 21 TMJs (55%) showed anterior disc displacement in closed mouths. Among those 21, medial and lateral disc displacement were recognized in 5 TMJs (13%). Of the 22 TMJs, which had clicking noise, 15 (68%) showed anterior disc displacement in closed mouths. A medial disc displacement was recognized in 3 TMJs (14%) and a lateral disc displacement was reconized in 5 TMJs (23%). There were 16 TMJs which had no clinical symptoms. Of the 16, nine (56%) showed anterior disc displacement. The medial disc displacement was recognized in 3 TMJs (19%) and the lateral disc displacement was recognized in 4 (25%). 5. Of the 39 eminences of the right mandibular fossa, 18 (46%) showed a high signal intensity and 21 (54%) showed a low signal intensity. Of the 39 eminences of the left mandibular fossa, 20 (51%) showed a high signal intensity and 19 (49%) showed a low signal intensity. Of the 39 right mandibular condyles, 35 (90%) showed a high signal intensity and 4 (10%) showed a low signal intensity. Of the 4, one had an erosion of the cortical bone. Of the 39 left mandibular condyles, 36 (92%) showed a high signal intensity and 3 (8%) showed a low signal intensity. Of the 3, one was accompanied by a deformity of the mandibular condyle.

View full abstract

In order to clarify an anthropological position of the Japanese of Yabakei based on Mongoloid dental variations, 6 tooth crown traits of the Japanese of Yabakei were examined and compared with 6 East Asia populations. In the six traits which show considerable difference between Sinodonty and Sundadonty, Double shoveling and 4-cusp in Yabakei were similar to those of Sinodonty, and Shoveling and Y-groove pattern were similar to those of Sundadonty. Carabelli's trait and Deflecting wrinkle lay between Sinodonty and Sundadonty. From a cluster analysis and multidimensional scaling analysis among 7 East Asian populations, the Yabakei was the nearest to the Chaoxian. Double shoveling and 4-cusp were approximate to those of Sinodonty than those of Taiwan. Shoveling and Y-groove pattern were approximate to those of Sundadonty than those of Taiwan. Carabelli's trait and deflecting wrinkle were most closely related to those of Taiwan. But the Yabakei was the closest to the Chaoxian.

View full abstract

Seventeen-week-old male Wistar rats corresponding to the prime of life in human were used. In control group, rats were fed with standard diet for 6 weeks. In calcium-deficient group and low calcium group, calcium-deficient and low calcium chows were fed for 3 weeks, followed by standard chow feeding for another 3 weeks. The effects of the dietary therapy on bone matrix formation were investigated, and results were as follows. 1. Weight No significant differences were observed among the control and experimental groups. 2. Radiographic findings In calcium deficient group, the width and number of trabeculae were decreased, arrangement irregular, and less radiopaque. Low calcium rats exhibited the equivalent appearance to that of control animals. 3. Microdensitometric findings Calcium deficient group exhibited lower density than control treatment. 4. Histopathological findings Control group exhibited dense matrix, thick cortex in both outer and inner circumferential lamellae, and well-developed Harversian systems. In contrast, reduction of lacunae and expansion of marrow cavities were observed in calcium deficient group. Resorption and irregular distribution of trabeculae were seen. Low calcium rats exhibited equivalent findings to that of control animals. 5. SEM findings Regularly distributed collagen fibrils were seen in matrix formative area in control treatment. Lacunae and canalicali opening were distinctly observed. In contrast, resorptive area expanded and collagen fibrils were loosely arranged in calcium deficient treatment. Calcareous microdepositions and collagen fibrils were seen in the upper section of bone formative areas. Low calcium rats exhibited comparable findings to those of control animals. 6. Hematological findings No significant differences could be seen among the control and experimental groups in serum level of calcium, phosphorus, ratio of calcium to phosphorus, sodium, potassium, and chloride. Calcium deficient rats exhibited higher GOT and CPK level than the control animals. From the above results, it is suggested that bone loss can be well restored by dietary therapy, particularly in low calcium group, if calcium is sufficiently stored in bone tissues.

View full abstract

This survey was based on the analysis of biopsy specimens that were diagnosed histopathologically in Department of Oral Pathology, Kyushu Dental College from 1991 to 1998. This paper was presented with special reference to 186 cases of squamous cell carcinomas. The results are as follows : The ratio of male to female was 1.5 to 1. Squamous cell carcinomas were seen mainly in the seventh decades of the life. The most frequent site of squamous cell carcinomas was found on the gingiva followed by the tongue and the oral floor. Histological differential diagnosis revealed 117 well differentiated squamous cell carcinomas, 43 moderately differentiated, 12 poorly differentiated. Metastasis to the cervical lymph nodes was histologically confirmed in 38 cases. Malignant transformation was observed in 17 cases with precancerous lesions : 3 cases with leukoplakia, 6 cases with epithelial dysplasia, 2 cases with carcinoma in situ, 6 cases with lichen planus.

View full abstract