Calcium metabolism has been known to change remarkably with advancing age. Although the mechanisms involved in the altered calcium metabolism with advancing age are not clearly understood, it is possible that these changes may involve an altered target organ response to calcitonin and/or parathyroid hormone or changes in the secretion rate of these hormones. In this study the role of calcitonin in the calcium metabolism with advancing age has been examined by comparing in rats of three different ages, 1) the recovery from CaCl2 induced hypercalcemia, 2) the hypocalcemic response to thyroid cautery, 3) the hypocalcemic response to exogenous calcitonin and 4) the content of calcitonin in the thyroid gland. It was found that older rats exhibited a retarded recovery from hypercalcemia, a smaller response to exogenous calcitonin and a smaller response to cautery of the thyroid gland, a procedure known to cause excessive release of endogenous calcitonin. Calcitonin content of the thyroid glands from rats of different ages did not differ significantly. However, since the oldest rat had larger thyroid glands, a significantly greater amount of calcitonin was found in the total thyroid glands of these rats. The release of calcitonin in response to hypercalcemia was not significantly different with advancing age. In conclusion, the thyroid gland of old animals still able to restrict hypercalcemia and it was not an insufficient release of calcitonin that was a causative factor in the delayed recovery from hypercalcemia in older rats.
the thickness o the clavicular cortex divided by the whole width of the clavicle espressed as per centage, clavicular score, was determined in patients between ages of 10 and years. A marked decrease took place in males between the second and thirde, whereas continuous and pronouned fall of the score was seen in females from 40 to 70 years of age. Between ages of 20 and 40, the score was significantly greater in females than in males, but such sex difference disappeared after 50. Patients with spinal osteoporosis had significantly lower clavicular score than those without. In patients with peptic ulcer, hypertension, and diabetes mellitus, the decline of clavicular score with advancing age followed the same patternas in healthy subjects. Patients more than 5 years after gastrectomy tended to give lower clavicular score than the agematched controls. Clavicular score thus appears to be a valuable index of the bone aging and metabolism.
Incidence and related factors of aortic calcification was studies on 775 (male 571 and female 204) apparently healthy persons who had undergone a regular medical examination. Aortic calcification was diagnosed by a routine chest film and a lateral film of abdomen. 1) Incidence of aortic calcification in men was 0% below 39 years of age, 2.9% in 40-49 years of age, 13.6% in 50-59 years of age and 26.8% in 60-69% years of age. That in women was almost the same. 2) Aortic calcification was classfied in 3 groups by the site of lesions. The calcification was visualised only at the aortic arch in 38 (47.0%), both at the aortic arch and along the abdominal aorta in 14 (16.9%) and only along the abdominal aorta in 30 (36.1%) of total 83 persons with aortic calcification. 3) There were no significant differences of mean serum cholesterol level, blood pressure and Ponderal index between persons with and without aortic calcification. 4) The incidence of aortic calcification was significantly higher in dibetic than non-diabetic persons.
A methodological evaluation of 133Xe clearance technique for determination of regional cerebral blood flow (rCBF) was attempted with special regards to geometrical distribution of the inert radioisotope in the brain and its relation to the extracranial monitoring system. Results are summarized as follows: 1) According to size and shape of the collimator used, distributions of intracranial isosensitive points of 133Xe were found to be markedly varied. The tapered-type collimator with a small orifice had the most localized monitoring area compared to cylindrical- or open-type collimators. 2) Repeated determinations of rCBF at the same portion(temporal area)of the same patient using various kinds of collimator revealed that average rCBF (f) were correlated with each other to a certain extent (P<0.05), but that both fast (ff) and slow (fs) flow components showed no significant correlations. There was, however, such a tendency that values of weight fraction of fast flow perfusion area (wf) measured by the tapered-type collimator were greater than those obtained by other types of collimators. 3) Each value of rCBF which was calculated by two compartmental analysis was well consistent with a corresponding rCBF value calculated by stochastic analysis using the same clearance curve of 133Xe. This was observed indifferent to kinds of diseases which patients were suffering from. 4) Comparisons of rCBF and average total cerebral blood flow (CBF, N2O method) in the same individual revealed a statistically significant correlation between fast flow component (ff) and CBF (r=0.511, P<0.01), suggesting that values of ff were reflected to a certain extent in CBF. However, there found no such significant correlations between f and CBF, or between fs and CBF. 5) A mean value of average rCBF in patients with cerebrovascular diseases (CVD) was significantly lower than that of other subjects without CVD (P<0.01), however, there were no significant differences in ff and fs between these two groups. The decrease in average rCBF in the CVD group was supposedly due to a statistically significant reduction of wf as a whole in the CVD group (P<0.01).
Metastatic tumors of the brain can rarely occur in the patients aged more than seventy and a carcinoma of the gall bladder seldom metastsizes to the brain constituting only 0.3% of all metastatic cerebral tumors. This is a report of an autopsy case of an old woman aged 75 with chief complaints of unconciousness and myoclonic seizure, who died after four months of admission. Autopsy findings revealed a cerebral metastasis of a carcinoma of the gall bladder, which invaded the left brachium pontis, corpus restiforme, left dorsal part of the pons and the medulla. Myoclonie seizure in this case might be explained by the interruption of the so-called Guillain-Mollarets triangle, the angles of which are at the red nucleus, inferior olive, and dentate nucleus.