A preparation of proteolipid, the principal component of the myelin sheath, was obtained from the bovine brain white matter with satisfactory reproducibility. Much of the lipid portion, containing most of the component sphingomyelin, was removed by precipitation with a mixture of ethanol and ether, and the precipitate fraction exhibited a preferential affinity for sphingomyelin. Since phosphatidylcholine, which did not show so much combining affinity for the precipitate fraction, exhibited an enhanced interaction by means of hydrogenation of the fatty chains, it is assumed that the affinity of sphingomyelin depends on the hydrophobic region of the molecule. Sphingomyelin is considered to interact with a complex formed by the ionic linkage between the basic protein and acidic phospholipid, which is obtained by further removal of the lipid portion from the precipitate fraction by dialysis.
A case of Behcet’s syndrome with vascular complications is presented. This case had a familial occurrence of Behcet’s syndrome. His vascular complications were deep vein thrombophlebitis of both legs, aneurysms of the left common iliac artery and the left femoral artery and the occlusion of the left subclavian artery. He was successfully operated on for the aneurysms. This paper discusses the problems accompanying the aneurysm of Behcet’s syndrome. The authors pointed out that the subclavian steal syndrome may be diagnosed as neuro Behcet’s syndrome and stressed the importance of vascular survay in Behcet’s syndrome when the patient complaints of thrombophlebitis.
A newly developed pit and fissure sealant, named Enamite, was studied technologically and clinically. Major ingredients of the sealant are a solution of 3% 2-hydroxy-3-β-naphthoxypropyl methacrylate in methyl methacrylate and poly (methyl methacrylate) powder, using tributylborane as an initiator. In comparison with other commercially available sealants, Enamite showed much greater adhesiveness to enamel, which was confirmed by scanning electron micrographic observations. The sealant was applied to 161 first molars in 99 children, aged 6-8 years, to determine the caries preventive as well as the caries retardation effect. Among the treated teeth, 98 were intact and the remaining had incipient caries. The right side teeth of each subject was assinged to the test side and the other side served as a control. Each child was evaluated every 6 months by clinical exploration and bite-wing X-ray survey. At the final examination, the electric conductivity test was also used for the caries detection. After 2 years the sealant was effective in preventing 57.1% of the occlusal caries on treated compared with control teeth. When evaluation was made by including the caries retardation effect teeth initially carious but remaining sealed after 2 years were counted as effective-, the sealant was effective in preventing or retarding 96.3% of the occlusal caries.
The purpose of this study is to prevent and control the reduction of residual ridges. The subjects used in this study consisted of 19 crab-eating monkeys which were divided into four groups according to the extraction area. These categories are 1U0L group (extracted on M1), 1U5L group (extracted on M1 and M3M2M1P2P1), 0U5L group (extracted on M3M2M1P2P1), and 5UlL group (extracted on M3M2M1P2P1 and M1). Impressions were taken before the extraction. Further impressions were taken at three week, six week, three month, six month, one year, and two year intervals after the extraction in order to observe morphological changes. Casts were made immediately thereafter and the cross-sectional areas of the residual ridges were measured by a standardized method with the aid of a Kubuskraniophor and a diagraph. The measurements taken of the right side, which was operated on, and the left side, which served as the control, were compared in order to observe changes in the form of the edentulous area. The results were as follows: 1) Increase in the Residual Ridge Areas: It is highly significant that the measurements of the M11 section of the 1U5L group and the M1 section of the 5UlL group gradually decreased until the sixth week, and then began to increase until the areas were approximately equivalent to the measurements of the areas before the extraction after a two year period. This may be due to the fact that along with the elongation of the neighboring teeth, the alveolar bone grew to such an extent that the resorption rate was surpassed. 2) Decrease in the Residual Ridges Areas: With the exception of the above-mentioned sections, almost all of other sections responded in the expected manner, that is, there was a sharp decrease in the areas of these sections. The decrease took place rapidly. Seventy to 80% of the total loss occurring over the two-year period took place in the first three months. After a sharp decline in the initial three-month period, the process continued at a slower pace. This gradual decrease after a short period of rapid decrease typifies the standard pattern of the edentulous resorption process.
The object of this study was to know what changes take place on the dental arch during the changing dentition. For this purpose, two excellent cases were observed from six to twelve years of age, and the following results were obtained from its observation. Enlargement of dental arch was observed till the shedding of the deciduous second molar. In the anterior segment, not only the increment of the arch width but also the labial inclination and/or movement of the permanent incisors was noted in conjunction with the eruption of these teeth. These tendencies were slightly observed during the eruption of the permanent canine. In the buccal segment, the space for the permanent buccal teeth increased during the time of eruption of the permanent canine and first premolar, and this increase made it possible for these teeth to align normally.
The present study deals with the pathologic change of the mandible following radiation therapy for oral cancer, histopathologically and roentgenologically. The results are summarized as follows: 1) As the resorptive change of the cortex and the trabeculae, irregular and bizarre resorption and enlargement of the lacunae were observed. 2) The grade of injury of the osteocytes was described by the percentage of the number of the lacunae, which were empty and in which the nuclei of the osteocytes could not be seen. Consequently these results cor responded considerably well with the clinical aspects. 3) Osteophytes in the spongy and compact bone were observed, and also narrowing and plugging of the Haversian canal and the canal of Volkmann with mineral were seen as the sclerotic change. 4) Thickening of the tunica intima, obstruction, disarrangement of the elastic fibers and distruption of the vessels were observed in the inferior alveolar artery, the arterioles, and also occlusion , which gave various appearances, in the vessels within the Haversian canal and the canal of Volkmann was seen. 5) The following four groups, based upon the radiographic change, were classified as: Group I, irregular osteolytic change; Group II, marked osteosclerotic change; Group III, irregular mixture of osteolytic and osteosclerotic change; and Group IV, no remarkable change.