We investigated the effects of changes in occlusal contacts on mandibular movement and electromyographic activities of the jaw muscles, Electromyographs (EMG) were recorded simultaneously from the inferior head of the right lateral pterygoid (Lpt), the anterior bellies of the digastric (Dig) and masseter muscles (Mm) with mandibular movement. We prepared a mandibular biteplate that was adjusted so that all the maxillary premolars and molars contacted the splint (AL). We then eliminated occlusal contacts on the bilateral first premolars, leaving contacts on 7__-6__-5__-∣5__-6__-7__-. Contacts were next eliminated on the second premolars, leaving 7__-6__-∣6__-7__- contacting. When contacts on the second molars were eliminated, only 6__-∣6__- were in occlusion. Then contact on the left first molar were eliminated, leaving occlusion only on 6__-∣. Subjects wearing each splint were instructed to perform 20 open-close-clench cycles (OCC) repetitively. Two sessions were carried out. Changes in time parameters and velocity of mandibular movement, opening distance, EMG activities and mandibular position during the open-close movement were observed following changes in the occlusal contacts. As the number of occlusal contacts decreased, the cycle time of mandibular movement and the duration and interval of jaw muscle activity decreased. The average acceleration of opening movement significantly increased from AL to 6__-∣6__- and significantly decreased from 6__-∣6__- to 6__-∣. The coefficient of variation (CV) for duration in AL was lower than for other contacts in both the jaw depressors and the Mm. Integrated EMGs of the jaw depressors and Mm significantly decreased following decreases in the occlusal contacts. Standard deviation (SD) of the lateral direction of the terminal closing position in 6__-∣ was greater than with other occlusions. These results suggest that the rhythm of OCC in AL was slower than for other contacts, although the regulation of rhythm was best for the full set of contacts. A decrease in the number of occlusal contacts may disrupt the rhythm of mandibular movement and mandibular position.

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Chemokines were initially reported as chemoattractant cytokines synthesized at inflammation sites and have been shown to induce leukocyte activation in various diseases, including autoimmune diseases, and in graft rejection sites. Natural killer (NK) cells, which express cytolytic activity without prior antigenic stimulation, are involved in the therateutic effect of cancer treated with IL-2 or by adoptive immunotherapy with IL-2. However, both therapies are associated with vascular damage, resulting in a systemic toxicity known as vascular leak syndrome. A novel chemokine, fractalkine, has a unique CX₃C motif and is expressed directly on activated endothelial cells. We investigated the effects of fractalkine on NK cell activity and NK cell-mediated damage of human endothelial cell line ECV 304. Freshly separated NK cells expressed fractalkine receptors and these NK cells efficiently adhered to immobilized fractalkine. lmmobilized fractalkine enhanced NK cell granule exocytosis in a dose-dependent manner. Furthermore, NK cells exhibited increased adherence and enhanced NK cytolytic activity against fractalkine-transfected ECV 304 cells compared to control ECV 304 cells. These results strongly suggest that fractalkine may play an important role not only in the binding of NK cells to endothelial cells, but also in NK cell-mediated endothelial cell damage, leading to vasculopathy and organ failure.

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We developed a new method, the Dropping Time Method (DTM), to investigate the wettability of the protein surface layer adsorbed on hydroxyapatite in aqueous solution. We then studied the relationship of the amount of adsorbed protein and wetting of the protein surface. We also investigated the adsorption of human serum albumin (HSA) on hydroxyapatite plates treated with acidulated phosphate fluoride (APF) in water. Although the surface of adsorbed HSA were fairly hydrophilic for high concentrations of HSA, the amount of protein depended on the adsorption time. At lower HSA concentrations, although the hydrophilicity of the HSA layer depeneded on the concentration of the APF, no great differences were observed in the amount of adsorbed protein. The surface of the protein layer became hydrophilic independent of the amount of adsorbed protein.

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We biochemically investigated the expression of cytokeratin in the vitamin A-deficient rat submandibular gland. The vitamin A deficiency suppressed increases in body weight from six weeks after breeding. Although the wet and dry weights of the submandibular gland, total protein per tissue dry weight, and retinol-binding protein in serum tended to decrease, DNA content per gland tissue dry weight tended to increase compared with normal rats. The expression of cytokeratins 5, 7, 10, 13, 14, 15, 17, 18 and 19 was observed with immunoblotting and two-dimensional electrophoresis profiles in extracts from both groups. The expression of cytokeratins 14, 15 and 19 was especially pronounced in the vitamin A-deficient rats compared with normal animals. These results indicate that vitamin A deficiency induces stratification in rat submandibular gland cells.

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Occlusal force with complete dentures is an important diagnostic parameter in clinical prosthetic dentistry. Considerable research has been done on the level of occlusal force in healthy individuals. Although the factors affecting these forces have not been clarified, we know from experience that alveolar ridge form plays an important role. In order to study occlusal forces in complete denture wearers, we measured force levels with strain gauges and evaluated the ridge form with a non-contact type high speed three-dimensional sharp measurement system. Using data obtained from patients seen at Osaka Dental University and Shanghai Second Medical University Hospitals, we studied the effect the maxillary and mandibular alveolar ridge forms had on occlusal forces, and found that the ridge form influenced occlusal force levels.

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We evaluated the effect of administration of fibrinolysin (Elase ointment) and an antibiotic (Periocline^<<【○!R】>>) in periodontal pockets. Each patient received the following treatment: scaling alone at one site (group A), Elase^<【○!R】> administration four times at one week intervals at a second site (group B), Periocline^<【○!R】> administration four times at one week intervals at a third site (group C), and Elase^<【○!R】> administration four times at one week intervals in combination with Periocline^<【○!R】> at a fourth site (group D). Clinical and microbiological evaluations were performed before treatment as a baseline and one week after completion of treatment. All groups showed improvement over the baseline. Counts of viable organisms, anaerobes and black pigmented gram-negative anaerobic rods improved in all groups after treatment compared with the baseline.

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We examined the relationship between E-cadherin (E-CD), protein kinase C (PKC) and assembly of the tight junction (Tj) in rat submandibular gland acinar cells using male Wistar rats weighing 250 to 300g. Several infusion mediums were injected into the oral opening of the main duct of the submandibular gland. The junctional complex of the acinar cells was double-labeled with anti-E-CD antibody and anti-ZO-1 antibody, which is anantibody for the first known protein component of the Tj. When Ringer's solution was injected in the duct, E-CD labels were highly concentrated at the adherens junction (Aj), and the Tj zone was exclusively labeled by ZO-1. In addition, the Tj was impermeable to microperoxidase. Evidently, the two proteins were not intermixed. Neither intraductal injection of anti-E-CD antibody solution nor stimulation by carbachol produced labels for ZO-1 at the Tj zone, although these proteins were occasionally intermixed at the Aj zone. In these cases, the Tj was permeable to microperoxidase. In traductal injection of anti-E-CD antibody solution with PKC agonist, resulted in a high concentration of E-CD labels in the Aj zone, while the ZO-1 was labeled exclusively in the Tj zone. We found that the Tj was impermeable to microperoxidase. These results suggest that E-CD plays a major role in mediating intercellular physical adhesion, and that PKC may be active in signaling the pathway activated by E-CD-mediated cell-cell adhesion. In addition, PKC agonist triggers the translocation of preformed Tj subcomplexes.

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Chemokines were initially reported as chemoattractant cytokines synthesized at inflammation sites and have been shown to induce leukocyte activation in various diseases. We have investigated the effects of a novel chemokine, fractalkine on NK cell activity. NK cells expressed fractalkine receptors and adhered efficiently to immobilized fractalkine. Immobilized fractalkine enhanced NK cell granular exocytosis in a dose-dependent manner. NK cells exhibited increased adherence and enhanced NK cytolytic activity against fractalkine-transfected endothelial cells compared with control endothelial cells. These results suggest that fractalkine may play an important role in NK cell-mediated endotheilal damage, leading to vasculopathy and organ failure.

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