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In vitro cell transformation of human embryo cells could be induced by the DNA purified from SV 40. The result shows clearly that cell transforms a part of viral DNA into the genome. In addition, for the purpose of clarifying th~ biological differences between the normal and transformants the alteration of cell membraneous structures of transformants (hamster and mouse fibroblasts) were observed from mechanism of phagocytosis. The iron colloid particles are taken up by normal diploid fibroblasts but not by the human and hamster transformants. This fact suggests a differ~nce in the molecular arrangement of the cell membranes between the normal and transformants. In the presence of histones, however, the transformants phagocytize the colloid particles very actively. The results show that cell membranes of transformants are altered in the molecular structure r~sponsible for the surface charge. In addition, there is no remarkable quantative differences of sialic acids on the cell surfaces of non-malignant and malignant transformants so that phagocytic activity might be correlated to the alteration of molecular composition of cell membrane itself rather than of cell surfaces, i. e, sialic acids.

The incorporation of tritiated thymidine into DNA molecules was studied by electr.:m microscopic autoradiography. To make autoradiogram in electron microscopic level, DNA was extracted from rat ascites hepatoma (AH 130) cells after in vitro incubation with tritiated thymidine. Extracted DNA samples were rotary shadowed with platinum palladium and covered with emulsion. Silver grains demonstrated on autoradiogram indicated tritiated thymidine to have incorporated into DNA molecules themselves. The incorporation was further confirmed by liquid scintillation counting of TeA soluble and insoluble fractions after DNase or RNase treatment of the DNA preparations.

Ring DNA from rat liver mitochondria has been examined by circular dichroism (CD) in the region of the 225 to 320 m/~ and the followings have been clarified. The ring DNA gives a CD spectral curve somewhat different from linear DNA from nuclei, showing a big positive peak at 266 m/~ and a small negative band at 243 m!~. That is, the positive CD band of ring DNA shifted by about 7 m/~ to the shorter wavelength side from the band of the ordinary nuclear DNA, 273 m!~. Negative band appeared at the same region as that of linear DNA but reduced in depth. Heat denaturation of the ring DNA induced a red shift of the positive band, by about 4 mp., but no change in negative band. From these experimental results it has been concluded that the ring DNA has highly twisted conformation and high in G.C contents, both of which are responsible for the blue shift of the CD spectrum.

For the purpose to investigate the physiological functions of microvillus ATPase, general properties of the enzyme were studied on the microvillus membranes isolated from rabbit intestinal epithelial cells. 1) ATPase of the microvillus membranes was activated with Mg2+. Mg.ATP complex was thought to be a subStrate of the enzyme. The Michaelis constant for ATP of the ATPase was a value of 0.8 to I .0 mM. 2) The microvillus ATPase was also activated with Ca2+, but the affinity was lower than a half of that of Mg2+. 3) The optimum pH of the ATPase was about 7.8. 4) Activity of the microvillus ATPase was markedly inhibited by treating with deoxycholate (DOC), and the activity inhibited was partially restored by washing the microvillus membrane with distilled water. The structure of the membranes destroyed by treating with DOC was also partially restored by the same procedure. 5) Ultrasonic treatment also markedly destroyed the microvillus membrane and inhibited ATPase activity. Damaged ultrastructure and ATPase activity both were partially restored by treating with phospholipid, EPL. 6) Simultaneous presence of Na+ and K + stimulated scarcely the ATPase of purified microvillus membranes. 7) The microvillus ATPase was slightly activated in the presence of n-glucose. Phloridin gave little effect on the activity of the microvillus ATPase.

We applied unidirectional MLC test to renal allograft in dogs, and investigated the correlation between the growth rates of MLC reaction and the intensity of rejection of the kidney transplants or the postoperative renal function. It was concluded that the grade of rejection became three plus (+ + +) when the rate of blastformation was more than 18 %, while it became one plus when the rate was less than 15 %. The rate of blast. formation was closely correlated with the strength of rejection of kidney transplants. However, the postoperative renal function was not always correlated with the mixed lymphocyte reaction.

For the purpose of elucidating more exact relationship between the process of carcinogenesis and aggregate-forming ability, we performed rotation cultures of a series of five liver cell lines derived from rats fed DAB for various period of d:l ys. As a result we found a tendency of the cells obtained from rats fed DAB for a longer period to form larger aggregates. The differences of the aggregate.forming ability among these cell lines were demonstrated well within one day, and more prominently after three days in rotaion culture. Histologically, the aggregates of all cell lines were composed of cuboidal epithelial cells, especially in some cell lines showing gland-like structures.

In order to know the organ distribution of Chinoform, I4C.Chinoform was injected into the tail vein of the mice, and radioactivity was measured in the chloroform soluble fractions in some organs and tissues containing non.conjugated Chinoform. The results obtained are as follows. 1. Uptake of Chinoform by the visceral organs was found to be in the following ascending order: fat tissue, kidney, spleen, liver, small intestine, (blood), muscle and eye, and marked uptake by the fat tissue and kidney was observed. 2. The presence of radioactive Chinoform in the chloroform soluble fraction of the central nervous system was recognized and it was almost in the same degree of specific radioactivity as that of blood. 3. A higher uptake in the chloroform soluble fraction of the sciatic nerve than that of central nervous system was recognized, and the value of the former was about 3 to 8 times as high as that of the latter. 4. The presence of Chinoform in the chroloform soluble fraction of the bile, although it increased after incu bation of the bile with j9-glucuro. nidase was observed. High radiogctivity of chinoform in the total fraction of the bile suggests a possible presence of "liver-intestine-circulation" of the drug.

Three cell lines, spontaneously transformed in vitro, MWE-l and MWE-2 originating from C3Hf/Bi mouse whole embryos and NHLu-l originating from newborn syrian hamster lungs were obtained. These transformed cell lines were characterized by short generation time, marked aneuploidy in chromosome numbers and tumor induction in vivo. Histological appearance of the tumors induced by MWE-l was fibrosarcomatous. Myogenic character in MWE-2 and epithelial character in NHLu-l were interesting features.

The frequency of recessive gene, heterozygotes and homozygotes in Japanese acatalasemia were estimated as 0.0038, 7.5 X 10-3 and 3.0 X 10-5 by DAHLBERG'S formula, and estimated as 0.00087, 1.73 xl 0-3 and 4.23 X 10-6 by KIMURA'S formula. The frequency of recessive gene was calcu. lated from the frequency of hypocatalasemia obtained by the screening method as 0.00083, and it was almost identical with that calculated 1:'>y KIMURA'S formula. The number of acatalasemia was estimated as about 423 by KIMURA'S formula.

The comparative effectiveness of subcutaneous administration of 20p·OH-P, pregnanolone and progesterone in oil to prolong gestation in rats was determined. As a result it was found that, while progesterone was shown to have activity, pregnanolone and 20j1-0H-P were ineffective in doses of 5 mg per day.

1. ANS fluorescence change at various energized stages of mitochondria was investigated. 2. Freshly prepared mitochondria manifest ANS fluorescence change during anaerobic-aerobic transition, but aged and inner mitochondrial membrane show remarkable changes. 3. These data suggest that freshly prepared mitochondria or those in energized state exhibit less hydrophobic environments or decrease the binding site of ANS. 4. Energy dependent light scattering changes indicating the configurational changes of mitochondria cannot be said to be identical with the pattern of ANS fluorescence changes indicating the conformational change of mitochondrial membrane. 5. Polarity of the membrane structure and binding site of ANS in submitochondrial particles and mitochondrial membranes have been discussed.

Japan was the first Asian country to introduce social insurance measures and she has expanded them during the last few decades. The first social insurance law was passed in 1922 dealing with worker's health insurance in general. It was followed by many schemes of social insurance. National Health Insurance in 1938, Seamen's Insurance in 1939, Employees' Pension Insurance in 1941 and so forth. After World War II the new Constitution was enacted by which the Japanese Government was made responsible for the provision of medical care services for the whole nation. At present approximately the whole population is covered by either one or more of the various social insurance schemes. The main social insurance programs are shown in Figure 1 and Table 1. Most of these insurance schemes are compulsory under Japanese law. Since it would be too difficult and complicated to explain all of these forms of social insurance in detail, we will discuss only about two schemes directly related to medical care services for the workers; namely, the Health Insurance Scheme for non. occupational diseases and disorders (sickness or injury off the job) and Workmen's Compensation Insurance for occupational diseases and disorders (sickness or injury on the job).

Serum diphenylamine reactions were performed in 156 patients, medical and surgical. On the surgical side, serum diphenylamine reactions were evaluated in 50 patients before operation and on the 7th and 12th postoperative days. The diphenylamine reaction was revealed as a determination of serum sialo-mucoprotein level. The above cases justify the assumption that the serum diphenylamine reaction informs us of the intensity of regeneration in the organism.

A high incidence of subnormal serum folic acid levels was observed in 48 patients receiving anticonvulsants (75 %). In peripheral blood, macrocytosis was detected in 46 % and an increase of hypersegmented neutrophils was also seen in 24 % of the patients. Correlation existed between these signs and low serum folate levels. The growth response of Lactobacillus casei and L. leichmannii was not suppressed by the addition of various anticonvulsants to the medium of the bioassay systems. Administration of 5 mg of folic acid for a month corrected macrocytosis and an increase of hypersegmented neutrophils significantly. Folic acid supply also decreased mean diameters of the nuclei of oral epithelial cells significantly. It is concluded that subclinical folic acid deficiency is common among the patients receiving anticonvulsants. Absorption of 3H.folic acid from the small intestine of rats was inhibited by large dose of diphenylhydantoin (20 mg) not by 5 mg. This fact suggests that in patients on diphenylhydantoin, the quantity balance of folic acid and diphenylhydantoin in the intestine regulates the absorption of folic acid.

Changes of H+ gradient at various energy states of mitochondria were studied. There was a close relation between the extent of H+ gradient and the level of ATP formation; the former decreased as a result of ATP synthesis but was not completely abolished. A partial depression of H+ gradient was also observed in the presence of uncouplers of oxidative phosphorylation. The H+ gradient seemed to be more closely related to the ion translocation than ATP formation. In the presence of Ca++ the energy of H+ gradient was utilized in translocating Ca++ rather than synthesizing ATP. These findings further substantiate the chemiosmotic theory of MITCHELL on mitochondrial electron and energy transfer.

Two cases of megaloblastic anemia associated with anticonvulsant drugs were studied. Both cases were inpatients of psychiatric hospitals and had quite inadequate intakes of food. The former had lung tuber. culosis and the second had febril illness before the manifestation of anemia. Multiple examinations including bone marrow smears, serum iron levels, vitamin B12 levels, estimation of urinary formiminoglutamic acid after histidine loading and folic acid tolerance test revealed that this anemia was due to folic acid deficiency. Complete hematological responses were ob3erved with injection of folic acid. Retrospective nutritional study on the second case was carried out. The study revealed that folic acid content of the diet of this hospital was 152 fl.g of free folate and 522 fl.g of total folate. The folic acid mtake of the patient was about 80 /1.g of free folate and 280 l1.g of total folate daily during a month before the manifestation of megaloblatic anemia. Importance of additional factors for the development of megaloblastic anemia in patients receiving anticonvulsants was discussed and it was concluded that most important factor was nutritional deficiency of folic acid.

Scanning electron microscope (SEM) observations were conducted mainly on the in vitro interaction state between ]TC-II cells derived from Ehrlich ascites tumor and regional lymph node cells obtained from the mice I0 days after transplantation of Ehrlich ascites tumor. Cells cultured on the cover glass were fixed with glutaraldehyde, dehydrated with graded acetone solution, and covered with carbon and gold, were observed by SEM. The results may be briefly summarized as follows. On the surface of ]TC.II cells themselves are seen numerous fine microvilli projecting out regularly at right angle to the cell surface, which become attached to the glass, and there can be observed vacuoles in the cytoplasm. Such microvilli are lacking at the tip of the pseudopodial projection. The lymph node cells aggregated to ]TC-II cell are lymphocytes of small or intermediate size, and the pattern of aggregation varies: some lymphocytes effect an intimate contact with the surface of target cell by their cellular projections; the contact is achieved by interdigitation of microvilli between lymphocyte and target cell; b:>th cells form a bridge connection with a simple projection from each; or the two cells make a broad surface.to.surface contact. It is not possible to differentiate sensitized lymphocyte from nonsensitized one, their cell shape is spherical with rough surface and some cells show hole on the surface.

For the purpose to confirm whether carotene is converted into vitamin A mainly in the intestine, fluorescence microscope observations as well as the fluorescence microphotometry for the estimation of fading state of the fluorescence were carried out on the fresh sections of the intestine, lung and liver of rats after oral administration of 11-carotene dissolved in oil, and suspended in water, and vitamin A in sesame oil as control. Yellowsih-green fluorescence of carotene is similar to that of vitamin A in color but the fluorescence of vitamin A fades away very rapidly within one minute while that of carotene does not fade or fade more slowly than that of vitamin A. Observations have revealed that, contrary to expectation, the administered carotene is not so readily converted into vitamin A in the intestinal mucosa, but after passing through the intestine without conversion to vitamin A, it is transported to the mesenteric lymph vessels, portal vein, and reaches the liver. In the liver, carotene appears as fatty droplets or micronized particles in the parenchymal cell. The conversion of carotene into vitamin A could not be observed in the intestine, liver and lung in the observations made one hour after the oral adminstration of carotene. Hower, it seems that carotene dissolved in minute fat droplets may be converted into vitamin A at water phase in tissues, after dissolution of carotene in fat and micronization of the fat droplets.

Bovine adenovirus type 3.induced tumor was transplanted subcutaneously through 25 generations in hamsters. Histological character of the tumors showed no basic differences from the primary one through all generations. There appeared metastatic foci in the lung, liver, kidney and lymph nodes in some animals.

Partially separated double-stranded RNA from purified Rous sarcoma virus, Schmidt.Ruppin strain, was observed by electron microscopy utilizing 8.M urea and protein monolayer technique. Furthermore, viruses in pair were frequently and viruses with two nuc1eoids were occasionally observed in ultrathin. sectioned specimens of chick cells transformed by RSV. From these results taking other reports in consideration, a possible mechanism of RNA replication in Rous sarcoma virus is proposed.