1. The effect of the basic protein isolated from tumor tissues on the liver TP activity of normal rat was examined.
2. Administration of the basic protein reduced TP activity. The minimum effective dose was 10mg.
3. The adaptive increment of TP activity with L-tryptophan was also reduced by the administration of the basic protein.
4. The basic protein did not inhibit TP activity in vitro.
5. The basic protein isolated from the liver of normal rat had no effect on TP activity even when 30mg of the basic protein was injected into rat.

View full abstract

1. Liver catalase activity and plasma iron level showed a remarkable decrease in tumor-bearing rats.
2. In early phase of tumor inoculation, liver TP activity of tumor-bearing rats tended to decrease the level, thereafter, the activity showing various levels.
3. TP activity of tumor-bearing rats was decreased strikingly by adrenalectomy.
4. The basic protein decreased liver catalase activity of adrenalectomized mice.
5. TP activity of pregnant rats was in normal level.
6. TP activity of tumor-bearing rats and its relation to the adrenal glands were discussed.

View full abstract

1. Successive transplantations of experimental osteogenic sarcoma in albino rats into the subcutaneous tissue of the backs of the same strain of albino rats were done.
2. The changes in the histological picture of this sarcoma during the course of transplantations were studied and the following results were observed. If the immature portions of the transplanted sarcomas are used successive serial transplantations are possible. However, at times, fibrosis, osteoplasia, and giant cell tumor like tissues were seen.
3. X-ray radiation, anticancerous drugs, predonin, and AAN were administered and their effects were observed. In the cases of X-ray radiation and anticancerous drugs, atrophy of the tumor cells and necrosis were distinct. In the anticancerous drug cases, the foci of necrosis were circumscribed. In predonin administered group, atrophy and fibrosis were conspicuous. In AAN administered group, almost no change was observed.

View full abstract

The N-demethylation rate of various derivatives of aminoazobenzene by rat liver homogenate was compared with each other in special respect to the carcinogenic potency. It was suggested that the poor N-demethylation was related to the weak carcinogenicity. Formaldehyde formed during the incubation was principally generated from N-methylated aminoazo dyes but not from N, N-dimethylphenylenediamine, a reductive product of DAB.
The role of formaldehyde in the carcinogenic mechanism was speculated.

View full abstract

Guinea pig serum was shown to have strikingly higher ability to inactivate in vitro the carcinogenicity of 20-methylcholanthrene than other animal sera. The mechanism involved in cancer insusceptibility of the guinea pig was discussed from the view point of this ability of its serum. The factor(s) responsible for the action in the serum remains to be determined.

View full abstract

Intrahepatic, especially intralobular topographic distribution of the so-called protein bound azo dye in rat was studied by means of C¹⁴-DAB autoradiography.
The distribution of the bound dye in the parenchymal liver cells was almost uniform among the three zones, peripheral, middle, and central, although there was a slight tendency to be less in the peripheral zone. Relatively small quantities of bound dye were proved to exist in Kupffer's cells as well as in the serum. The protein bound azo dye was scarecely detected in the bile duct systems.

View full abstract

Chromosomes in nine spontaneously developed leukemias in AKR strain were analysed. Among them five were characterized by the modal chromosome number 40; two had the mode at 41. The remaining two had a bimodal distribution of chromosome numbers, one with one mode at 40 and the other at 41, and the other with one mode at 40 and the other at hypotetraploid 76.
Three strains of leukemias induced by X-irradiation were observed. The mode in one was at 40 (C57BL). Of two leukemias, developed in RF mice by double treatment with X-ray and 20-methylchoranthrene, one was characterized by the mode at 41 and the other by bimodal variation with modes at 41 and 42 chromosomes.
No marker chromosomes were found in all those leukemias, and no chromosomal difference was found between spontaneous and induced leukemias.

View full abstract