Sinec 1942, when Caspersson and Brachet published their studies, it hes become clear that nucleic acid is an important constituent of the cell, playing a primary part in its existence and development. There are, however, not many studies on alteration in nucleic acid amount in a short time after irradiation of the tissue or the cell, and on relation between this alteration and cell division. ln view of this, the author attempted by chemical method to determine nucleic acid concentration per cell of Yoshida's sarcoma, and to seek, from its change, the effect of irradiation on the cell.
At 4-7 days after transplanting the sarcoma into rats, they were abdominally irradiated in single doses of 100, 200, 500 and 10, 000γ. After a definite time, ascite was taken, from which nucleic acid was extracted by Schneider's method. Then DNA and RNA per cell were colorimetrically detereined by diphenylamine reaction and orcin HCl reaction, respectively. The results were as follows :
1) Normal Yoshida's sarcoma gave relatively consant values, DNA per cell being 10.65± 0. 45× 10^-6γ, and RNA 17. 98±1. 16 × 10^-6γ.
2) After irradiation with 100γ, both DNA and RNA showed a slight increase at 1 hour, but at 3 hours they returned to the initial values, exhibiting thereafter no remarkable change.
3) after irradiation with 200γ, no change appeared as late as 3 hours, but appreciable increase at 6 hours, more reme remarkably in RNA than in DNA. The values transiently at 12 hours, but again rose at 18 hours, returning to the initial level at 24 hours.
4) After irradiation with 500γ, DNA showed no change, while RNA gave slight increase at 18 hours to 24 hours.
5) After irradiation with 10, 000γ, neither DNA nor RNA showed any definite tendency of change.
6) A consistent relation could be seen between change in nucleic acid and number of cell division. After irradiation with 100γ, cell division decreased to the minimum level at 1 hour, rising abruptly thereafter, in correspondence with increase in nucleic acid. The same relation was observed at 6 hours after irradiation with 200γ, but no consistent relation was obtained after irradiation with 500γ.

View full abstract

To define the standard for the normal physiological status of rats, about 300 Wistar strain rats, bred in our department, were examined for body weight gain with age in day, and weight of 11 organs-hypophysis, thyroid, adrenal, thymus, testis, ovary, uterus, heart, liver, spleen and kidney-were obtained for each body weight group. And the results were compared with Donaldson's report.
As to body weight gain, our results approximately agreed with Donaldson's, but seemed rather lower as compared with recent growth curve for rats.
As to correlation of body weight to weight of thymus, testis and ovary, our results tended to differ remarkably high in the latter. Weight of hypophysis and adrenal were evidently higher in females than in males, whereas those of thymus and kidney were conversely higher in male. In adrenal weight, there were remarkable differences between right and left side, the left exceeding the right without regard to sex.
Female rats were examined for vagina opening and the first estrus, and from these results and organ weight increase, the puberty for sex was estimated to range 4575 days of age.
Further, some discussions were made on whether it is reasonable to express the weight of the organ in ratio to body weight.

View full abstract

1. An anaerobic strain of Clostridium tertium was isolated from the soil which produced an enzyme which, acting on O(H) substance and group O red cells, abolished not only O(H) activity but also cross-reactivity with anti-pneumococci Type XIV chicken serum. The enzyme preparation decomposed O(H) substance, converting it into a substance which contained D-galactosamine and/or D-glucosamine as antigenic determinant. This enzyme preparation also decomposed Le^a substance. In addition to this enzyme, the strain produced A-decomposing enzyme.
2. These enzymes were found in a fraction which precipitated at 40-50% ammonium sulfate saturation of culture filtrate of the strain. By means of DEAE cellulose column chromatography, the enzyme decomposing O(H) and Le^a could be separated from the A-decomposing enzyme. For both of them, the optimal pH ranged 6.8-7.2, the optimal temperature 30-37°C, and after heating at 100°C. for 5 minutes, the enzymes were inactivated.
3. The actions of these enzymes were inhibited by such metal salts as mercuric chloride and copper sulfate. The enzymic action to decompose O(H) substance reacting with anti-O(H) antibody in eel serum was inhibited strongly by L-fucose and slightly by lactose and D-galactose. The enzymic action to decompose O(H) substance reacting with anti-O(H) antibody in anti-Sh. dysenteriae chicken serum was inhibited strongly by D-galactose, lactose, D-galactosamine, and N-acetyl-D-galactosamine, and slightly by L-fucose. And the enzymic action to decompose O(H) substance reacting with antibody in anti-pneumococci Type XIV chicken serum was inhibited by D-galactose, lactose, N-acetyl-D-glucosamine, α-ethyl-N-acetyl-D-glucosaminide, D-glucosamine and L-fucose. The action of Le^a decomposing enzyme was inhibited strongly by D-galactose and L-fucose, and also inhibited by lactose, melibiose, N-acetyl-D-glucosamine, α-and β-ethyl-N-acetyl-D-glucosaminide and N-acetyl-D-galactosamine. And the action of the A-decomposing enzyme was inhibited most strongly N-acetyl-D-galactosamine, less strongly by lactose and D galactose, and slightly by N-acetyl-D-glucosamine.

View full abstract

A japanese woman aged 31 fell in November, 1957, striking her left thigh and then noted ensuing local pain. Threem onths later, she became aware of weakness of left lower extremity. She was admitted in February, 1959, with chief complaints of progressive weakness of the extremity, difficulty in walking and inability to stand and to raise her arms., over the sholder. Examination revealed atrophy of most skeletal muscle groups. She died of respiratory failure 19 months after the onset of ailment. The past and family history were not contributory.
necropsy revealed generalized atrophy of the trunk and extremity musculature. No gross abnomality was found in external configulation and in various cut sections of the brain and spinal cord.
Microscopically, there was an evidence of cellular degeneration of ventral horn cells in all the section of spinal cord associated with a glial tissue replacement in the damaged area. A mild degree of myelin sheath degeneration was observed in the anterolateral colums. Sections of medulla revealed similar involvement of hypoglossal nuclei. Sections of skeletal muscles disclosed atrophic muscle fibers separated by cluster of normal appearing fibers.
The pathologic picture of this case was characterized by muscular denervation atrophy and degenerative processes of the central nervous system with selective involvement of the lower motor neuron which conformed classic description of the progressive spinal muscular atrophy of Duchenne Aran type.

View full abstract