Regenerative capacity of augmented bone in rat calvarial guided bone augmentation model

PURPOSE: Guided bone regeneration (GBR) is the most widely used technique to regenerate and augment bones. Even though augmented bones (ABs) have been examined histologically in many studies, few studies have been conducted to examine the biological potential of these bones and the healing dynamics following their use. Moreover, whether the bone obtained from the GBR procedure possesses the same functions as the existing autogenous bone is uncertain. In particular, little attention has been paid to the regenerative ability of GBR bone. Therefore, the present study histologically evaluated the regenerative capacity of AB in the occlusive space of a rat guided bone augmentation (GBA) model. METHODS: The calvaria of 30 rats were exposed, and plastic caps were placed on the right of the calvaria in 10 of the 30 rats. After a 12-week healing phase, critical-sized calvarial bone defects (diameter: 5.0 mm) were trephined into the dorsal parietal bone on the left of the calvaria. Bone particles were harvested from the AB or the cortical bone (CB) using a bone scraper and transplanted into the critical defects. RESULTS: The newly generated bone at the defects' edge was evaluated using micro-computed tomography (micro-CT) and histological sections. In the micro-CT analysis, the radiopacity in both the augmented and the CB groups remained high throughout the observational period. In the histological analysis, the closure rate of the CB was significantly higher than in the AB group. The numbers of cells positive for runt-related transcription factor 2 (Runx2) and tartrate-resistant acid phosphatase (TRAP) in the AB group were larger than in the CB group. CONCLUSIONS: The regenerative capacity of AB in the occlusive space of the rat GBA model was confirmed. Within the limitations of this study, the regenerative ability of the AB particulate transplant was inferior to that of the CB particulate transplant.

A basic study for establishing a suitable exercise prescription with long distance walking. II / 体力科学

The present study was performed to investigate the effects of 120 km walking, 40 km a day for 3 successive days on the condition that taking rest and foods freely, upon physical functions for healthy male and female subjects. All measurements were enforced at postabsorptive state early in the morning for the 10 successive days including the days of walking. Blood pressure, heart rate, and body weight were measured every morning. Blood samplings enforced, too. Urine collections were enforced from first day to 7 th day. The results obtained were as follows;<BR>1) There were no changes in heart rate, blood pressure, and body weight, which were measured early in the morning, before and after 120 km walking.<BR>2) Serum GOT and GPT activities had little changes, while serum LDH, α-HBDH, and CK activities increased gradually after walking.<BR>3) Serum CK-MB activities, which indicate myocardial injury, increased after walking, on the contrary CK-MB/CK ratio decreased. It was suggested that effects of 120km walking to myocardium were rather than slight ones.<BR>4) In spite of the same sorce in which serum CK-MB and LDH-1 were resulted, both did'nt exhibit same patterns in serum.<BR>5) Serum lipids decreased gradually after walking.<BR>6) Urinary excretion of creatinine and uric acid increased after 120km walking especially.<BR>7) If it is allowed to take sufficient foods and rest, 120km walking, 40km a day for 3 successive days, would not result in such a physical stress over the following days.

EFFECT OF TAURINE ON THE METABOLISM WITH EXERCISE (II) / 体力科学

Effects of 5 km running upon taking a low-carbohydrate, high-fat and protein diet on the body, in fourteen healthy young males and three healthy young females, all being affected by taurine inducement, were investigated by double blind test method. The results obtained were as follows ;<BR>1) As to the degree of in heart rate upon 5 km running, in males, there were no differences between taurine administration group (M-group) and placebo administration group (P-group) . But in females, recordings in P-group were much larger than those of M-group.<BR>2) As to the degree of increase in systolic blood pressure upon 5 km running, in males, no differences between both groups were observed, but in females, recordings in P-group were larger than those of M-group.<BR>3) Both serum creatine kinase (CK) and creatine kinase isoenzyme (CK-MB) activities did not recover to pre-exercise levels during 3 days after 5 km running in both groups of both sexes.<BR>4) In the rate of CK-MB against CK, not only P-group of females had extraordinary high levels immediately after 5 km running, but also P-group of both sexes had higher levels on 3rd and 5th day after 5 km runnning than M-group.<BR>5) In both sexes P-group was larger than M-group in the degree of increase in blood lactate and serum triglyceride levels.<BR>6) As to the changes in serum total protein levels, in males, no differences between both groups were observed, but in females, P-group had extraordinary low levels on 1st day after 5 km running and maintained low levels during 5 days recovery.<BR>7) As to the changes in both serum total fatty acids levels and the rate of unsaturated fatty acids against total fatty acids, no differences were observed between both groups of both sexes.<BR>8) As to the degree of increase in plasma noradrenalin and adrenalin levels, in males, no differences between both groups were observed, but in females, recordings in M-group were larger than those of P-group.

EFFECT OF TAURIN ON THE METABOLISM WITH EXERCISE (I) / 体力科学

Effects of 20km running uppn taking a low-carbohydrate, high-fat and protein diet on the changes in blood pressure, heart rate, body weight, skinf old thickness, blood components and urinary recordings in five healthy young men were investigated and the changes in these items which occured by taurine inducement were studied by double blind test method. The results were as follows:<BR>1) As to the degree of decrease in body weight in 20km running, the case in taurine administration (T. A.) was more than in placebo administration (P. A.) .<BR>2) As to the degree of increase in systolic pressure upon 20km running, T. A. was less than P. A. 3) The rate of creatine kinase isozyme (CK-MB) against creatine kinase (CK), which increased after 20km running in P. A., was possible to reduce by T. A.<BR>4) T. A. was less than P.A. in the rate of increase in lactate dehydrogenase (LDH) on 20km running.<BR>5) In P. A., triglyceride increased after 20km running, but in T. A., it decreased.<BR>6) T. A, much influenced the rate of individual fatty acid composition on 20km running<BR>7) T. A, was more than P. A. in the secretion of adrenaline on 20km running.<BR>8) No changes were observed in other blood components and urinary kallikrein.