GOT was extracted from the livers of 7, 17, 27 and 37 week-old SAM-P/8//ODU showing senescence acceleration, which were the experimental group, and SAM-R/1//ODU, which were the controls. While comparing the serum GOT, we investigated age-related changes in the liver GOT activity, in the distribution of the GOT in organelles, and in its isozyme patterns, and searched for characteristics of the aging phenomenon. The following results were obtained.
1) Together with the aging, the experimental group after 17 weeks of age showed decreases in serum total protein and the ratio of liver weight to body weight.
2) Both groups showed a decrease in liver GOT activity following a peak value at 7 weeks of age. While both groups maintained a ratio of liver GOT to GPT of greater than 1.0, this value decreased with age, and shifted to less than 1.0 at 37 weeks. This decrease was particularly marked in the experimental group. Although the age-related changes in serum GOT activity were less than those for the liver, they were greater in the experimental than in the control group, and the ratio of serum GOT to GPT became large in the experimental group at 37 weeks of age.
3) Together with aging, increases were observed in the subcellular distribution of liver GOT in the mitochondria and cytoplasm fractions, while there was a decrease in the lysosome fraction. However, there was very little age-related change in the liver GPT.
4) The distribution ratio of GOT-I and GOT-II isozymes which appeared in the liver mitochondria and cytoplasm fractions changed considerably in the experimental group with aging. The serum GOT was composed only of GOT-II isozyme, and showed no age-related changes.
The above findings relating to GOT suggest that there was an increase in membrane permeability or cellular degeneration in the liver of the experimental group at 37 weeks of age. It is assumed that these changes are characteristic of senescence acceleration.

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We investigated the glycosaminoglycan (GAG) in healthy and inflamed gingiva distal to the most distal mandibular molar in humans. GAG composition was determined by electrophoresis on cellulose acetate strips. Unsaturated disaccharides produced from chondroitin sulfate (CS) and dermatan sulfate (DS) by specific enzymatic digestion were determined by high-performance liquid chromatography.
The results obtained were as follows :
1) The amounts of total protein and DNA were increased, and hydroxyproline was decreased in the inflamed gingiva.
2) GAG in both the healthy and inflamed gingiva consisted of CS, DS, heparan sulfate, and hyalu ronic acid.
3) GAG (uronic acid) in the inflamed gingiva was increased. In particular, there was a greater increase in CS and DS than other components.
4) Unsaturated disaccharides from CS both in the healthy and inflamed gingiva consisted of non-sulfated unsaturated disaccharide (ΔDi-0S), and monosulfated unsaturated disaccharides (ΔDi-4S and ΔDi-6S). However, the ratio of monosulfated unsaturated disaccharides to non-sulfated unsaturated disaccharides was greater in the inflamed than in the healthy gingiva.
5) Unsaturated disaccharides from DS both in the healthy and inflamed gingiva consisted of non-sulfated unsaturated disaccharide (ΔDi-0S), monosulfated unsaturated disaccharides (ΔDi-4S and either ΔDi-6S or a combination of ΔDi-6S and ΔDi-UA2S), and disulfated unsaturated disaccharides (ΔDi-diS_B, ΔDi-diS_D and ΔDi-diS_E). In the inflamed gingiva, there was a greater increase in ΔDi-4S than other unsaturated disaccharides.
These results seem to indicate that gingival inflammation affects the metabolic pathways of GAG. This may be partially brought about by changes in the polysaccharide chain structure of GAG.

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We investigated the effects of various retrusive movements on mandibular position by simultaneously recording the position of condylar and incisor points.
1. During retrusive movement the average distances between intercuspal position (ICP) and retruded contact position (RCP) for the condylar and incisor points were 0.94 and 0.62 mm, respectively.
2. The condylar position obtained during voluntary retrusive movement was the same regardless of the method of movement used.
3. The average distance between ICP and RCP for the condylar point during passive retrusive movement was 1.04 mm, which was greater than that during voluntary movement.

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We investigated the localization of E-cadherin, a Ca^<2+>-dependent cell-cell adhesion molecule, in clinically healthy and inflamed human gingiva, and oral squamous cell carcinoma biopsy specimens, using immunohistochemical methods. The expression of E-cadherin was strong in the cells from the gingival basement membrane to the stratum spinosum. Although the intercelluar influence of E-cadherin was observed in the cancer nest, its effect varied between different regions. The absence of E-cadherin expression in the keratin layer results in the easy shedding of these cells, and the decrease in E-cadherin expression in cancer cells suggests a potential for tumor metastasis.

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I non-invasively estimated the biomechanical properties of the human temporomandibular joint (TMJ) region. The biomechanical properties, damper : c, spring : k and mass : m, were analyzed for 28 normal subjects using an automatic system composed of a device for measuring mechanical mobility of the joint and a data analysis unit with a microcomputer. The values for c, k and m were affected by posture and opening position. The coefficient of variation in the mechanical properties of the TMJ varied about 5% both over one day and over one week. The mechanical properties in males were significantly greater than those in females (p<0.05). The mechanical properties of the TMJ region could be estimated non-invasively using the method.

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We isolated and purified the viscous material from Prevotella intermedia strain 17 and determined its chemical composition. Viscous materials obtained from both the culture supernatant and the cell surface were isolated, purified and compared. Both consisted of carbohydrates and did not contain protein. They gave similar elution patterns by GLCs and had a mannose/glucose ratio of 5 : 1. Neither uronic acid nor hexosamine was detected. Both materials appeared as fine fibrous-like structures under electron microscopy, indicating that the cell-free and cell-bound viscous materials are the same and that they are primarily carbohydrate.

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[in Japanese]

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[in Japanese]

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[in Japanese]

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[in Japanese]

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[in Japanese]

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