Acta Medica Okayama volume14 issue1

The unsaturated fatty acid fraction extracted from the liver of rabbit irradiated with X-rays exerts a strong cytotoxic effect on human coelothelioma cells and Yoshida sarcoma cells both in vitro and in vivo. The cell damage seems to initiate at the nucleus, finally leading to the complete cytolysis. The inhibiting effect of this substance on the mitosis of Yoshida sarcoma cells can be observed, especially marked from prophase up to metaphase giving almost the same results obtained after X-ray irradiation. From these results and the observations reported by several authors on the cell damage by X-ray irradiation, weshould call special attention to the fact that the essential mechanism of X-ray irradiation can be attributed to the cell toxin produced after the irradiation.

1. The unsaturated fatty acid fraction (OX) from the liver of irradiated rabbits contains substance which has the same effects as X-ray irradiation on the testicular cells. 2. This substance introduced intravenously causes the degeneration of the germinal cells with the formation of giant cells or multi-nucleated cells and the mitotic abnormalities. 3. The DNA content of the cell also shows the changes exactly identical with that seen after X-ray irradiation. 4. From these results we conclude that the X-ray injury will be mainly due to the production of some toxic substance which is found in the unsaturated fatty acid fraction and severely affects the cells in mitosis and DNA metabolism.

1) The influence of thyroid secretion upon the induction of leukemia in Dba/2 male mice by methylcholanthrene was investigated. Radiothyroidectomy significantly reduced the incidence of leukemia in these mice. This reduction in incidence did not occur if radiothyroidectomy was performed after the administration of the carcinogen. 2) Data indicated that hypothyroidism following radiothyroidectomy interfered with the initiation rather than the promotion of methylcholanthrene- induced-Ieukemogenesis. 3) No correlation between incidence of leukemia and body weights in the mice was noted.

Vital observation on the cellular morphology of the normal human blood cells was conducted by means of bone marrow culture successfully in conjunction with vital staining with Janus green B and neutral red. A special attention was paid for the alterations of the cellular structures in the course of the culture. The findings are summarized as follows : 1) Intracellular particles with affinity to Janus green B or neutral red were classified into minute granules, granules, vacuoles, and mitochondria. Morphologic features of each type of the particles were studied in detail. 2) Two types of granules are present in neutrophilic and eosinophilic blood cells, whereas one type of granules is present in basophilic blood cells. Eosinophilic and basophilic granules show characteristic pole formation in them at the terminal stage of the staining. 3) The rosette formation in the mature monocyte and the aggregations of neutral red vacuoles in the mature neutrophil and the mature lymphocyte were characterized. 4) The cluster of neutral red vacuoles is characteristic of the erythroblast. 5) The mitochondria of the mature neutrophil and the mature monocyte participate in producing neutral red vacuoles.

Leukemic cells were cytologically studied in the human bone marrow culture by the utilization of vital staining of Janus green B and neutral red. The minute cellular morphology of various types of leukemia was studied with special reference to their alterations in the course of the culture. The cytologic deviation of leukemic cells from the corresponding normal blood cells was clarified on monocytic leukemia, chronic myelogenous leukemia with the blastic crisis, chronic myelogenous leukemia, and acute and chronic lymphocytic leukemias.

1. The DNA contents in mature lymphocytes of the mouse, rat and man are kept almost constant. 2. The variety in the DNA contents in tumor cells is attributed to the rapid DNA synthesis taking place at the interphase, though the degenerating cells and the cells in abnormal mitosis can not be discarded as the source of the variety in DNA content. 3. The RNA content in AH-130 (ascites hepatoma) is less than that in normal liver cells.

With the purpose of revealing the biological effects of the X-ray irradiation the authors extracted phospholipids from the liver of irradiated animals and proved that this substance has the action to inhibit the growth of the bone marrow cells, the motility of pseudo-eosinophilis and the erythropoiesis in tissue culture, suggesting that the injury will mainly be induced by the toxic substances produced by irradiation.