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S Odashima

Publications and source records attributed to S Odashima.

At least 55 records · Page 3Linked to original sources

Effects of glycyrrhizin and glycyrrhetinic acid on growth and melanogenesis in cultured B16 melanoma cells.

The effects of glycyrrhizin (GL) and its aglycone, glycyrrhetinic acid (GA), on the growth and differentiation of mouse melanoma (B16) cells in culture were studied. GA inhibits the growth of B16 melanoma cells, causes morphological alterations and stimulates melanogenesis. GL also resulted in the same changes but only when the concentration was about 20 times more than that needed for GA. When GA was removed after 84 h of treatment, the growth rate recovered slightly, but the doubling time was about twice that of the control. Cytofluorometric analysis showed that the growth inhibition of GA is the result of inhibition of the transfer from G1 to S phase.

Animals↗

DNA synthesis in Bloom's syndrome fibroblasts.

The relationship between relative rates of DNA synthesis and DNA content in Bloom's syndrome fibroblasts (BS cells) was investigated by flow cytometry. The cells were pulse labelled with 5-bromo-2'-deoxyuridine (BrdU). The BrdU content and cellular DNA content of individual BS cells were simultaneously measured by flow cytometry in which the cells were double-stained by a FITC-conjugated anti BrdU monoclonal antibody (mAb) for the BrdU content (green) and by PI (propidium iodide) (red) for total DNA content. Their red fluorescence histograms were analysed by a microcomputer to evaluate the cell fractions of each S compartment. The BrdU uptake in the early S phase of BS cells was lower than that of normal cells (fibroblasts from skin of a normal human), whereas the uptake in the middle and late S phase was essentially the same as that of normal cells. The early S phase in BS cells accounted for over 50% of the S phase cells. These findings suggest that, in comparison with normal cells, the rate of DNA synthesis in the early S phase of BS cells is lower, but is identical to controls in the middle and late S phases.

Bloom Syndrome↗

Evaluation of the phagocytosis of microspheres in V79 cells by flow cytometry.

Phagocytosis of microspheres in V79 Chinese hamster lung cells was investigated by flow cytometry. Fluorescent microspheres (1.8 micron diameter) were used as the ingesta. Change in the number of V79 cells containing fluorescent microspheres was measured as an index of phagocytic activity. With time there was a sigmoidal increase in cells containing microspheres. The phagocytosis of microspheres is partially explained by two parameters introduced to describe the sigmoidal curves.

Animals↗

Effects of saikosaponin-d on aminonucleoside nephrosis in rats.

The effects of saikosaponin-d extracted from the roots of Bupleurum falcatum L. on aminonucleoside nephrosis were studied in rats. Urine protein excretion in rats receiving aminonucleoside alone was significantly elevated on the 2nd day after the last injection of aminonucleoside and reached a peak on the 11th day. Urinary protein on the 11th day was reduced by 48 and 46%, respectively in animals treated with saikosaponin-d from the 2nd and 8th day after the last injection of aminonucleoside. Electron microscopically, the degree of abnormality, e.g. loss or fusion of foot processes, in the glomerular epitherial cells was significantly lower in the rats treated with saikosaponin-d after aminonucleoside injection than in the rats treated with aminonucleoside alone. It is concluded that saikosaponin-d prevents the development of proteinuria induced by aminonucleoside in the rat.

Animals↗

Flow cytometric determination of cell cycle parameters of V79 cells by continuous labeling with bromodeoxyuridine.

A simple method with which to determine the cell cycle parameters, TG1, TS and TG2M (the durations of the G1, S and G2 + M phases) is described. V79 Chinese hamster lung cells were used to evaluate the method. After continuous labeling with bromodeoxyuridine (BrdU), V79 cells were stained with anti BrdU-monoclonal antibody with FITC (fluorescein isothiocyanate) and with PI (propidium iodide). The individual cells were checked by flow cytometry for green and red fluorescences whose signal intensities corresponded to the BrdU and cellular DNA contents. The durations of G1, S and G2 + M phases of V79 cells were determined by measuring the cell fractions containing the nonlabeled G1, labeled S and nonlabeled G2 + M phases. The reliability of this method is discussed.

Animals↗

Effect of saikosaponin derivatives upon the immune response against T-dependent and T-independent antigens in mice.

Effect of water soluble extracts and purified derivatives from the root of the plant Bupletum falcatum L. upon the immune response of BALB/c mice was investigated using heterologous erythrocytes and bacterial lipopolysaccharide. This Chinese Medicine is famous for its reputed anti-inflammatory, anti-tumor and other biological activities, and has been widely used alone or in a complexed form since ancient times in Oriental Countries. The effect on immune responsiveness of this drug was judged by the measurement of antibody secreting cells causing localized hemolysis in agar gel. The purified derivatives, Saikosaponin (SS) a and d, suppressed anti-SRBC plaque-forming cells (PFC), but the other derivatives, b1 and b2 and c, did not. Moreover, derivatives a and d also enhanced anti-LPS PFC. From experiments establishing minimum effective doses for anti-SRBC PFC in mice, one mg/kg was optimum for BALB/c mice. The effect of the drug on antibody formation against heterologous erythrocytes was nonspecific because treated mice had greatly depressed PFC responses against both sheep and rabbit erythrocytes. The phenotypic effect of this drug as judged by PFC against T-dependent or T-independent antigen was not identified. However, it was suggested that the purified derivatives SSa and d stimulated both T- and B-cells. The possible mechanism of effect against immunocompotent cells is discussed.

Animals↗

Malignant fibrous histiocytoma of the lung.

A 75-year-old woman was admitted to a hospital for diagnosis of pulmonary infarction and died during treatment. An autopsy revealed a tumor 5 cm in diameter in the hilus of the left lung, spreading into the posterior mediastinum, and a metastasis was also found in the right lung. Histologically, this tumor consisted of two kinds of cells; one of fibroblast-like cells and the other of histiocyte-like cells, showing a storiform pattern. Furthermore, a positive staining for alpha 1-antitrypsin, but negative for CEA, keratin or S-100 protein was seen. Therefore, it was diagnosed as malignant fibrous histiocytoma (MFH) originating in the hilus of the left lung. In addition, many foci of hemorrhagic infarction due to metastasis and infiltration of the tumor into the pulmonary arteries were observed in the right lung. MFH is one of the rarest primary tumors of the lung.

Aged↗

Effects of saikosaponin-d on enhanced CCl4-hepatotoxicity by phenobarbitone.

The effects of saikosaponin-d extracted from the roots of Buplerum falcatum L. on increased toxicity of CCl4 and increased activities of microsomal enzymes induced by phenobarbitone have been examined. Saikosaponin-d showed protection against the CCl4-hepatotoxicity enhanced by phenobarbitone. It also inhibited increases in the content of cytochrome P450 and NADPH-cytochrome c reductase activity, which are induced by the phenobarbitone treatment, but the spectral characteristics of P450 were not altered. The rate of microsomal lipid peroxidation by NADPH and CCl4 was significantly lowered in-vitro in rats pretreated with phenobarbitone and saikosaponin-d compared with those pretreated with phenobarbitone alone.

Alanine Transaminase↗

Control of phenotypic expression of cultured B16 melanoma cells by plant glycosides.

The effects of two plant glycosides, ginsenosides Rh1 and Rh2, on the growth and differentiation of mouse melanoma (B16) cells in culture were studied. These plant glycosides have a dammarane skeleton resembling a steroid skeleton as an aglycone. Ginsenoside Rh2 inhibits the growth of B16 melanoma cells, causes morphological alterations, and stimulates melanogenesis at high cellular density. When ginsenoside Rh2 was removed after 2 or 6 days of treatment, the growth rate recovered slightly but not completely, during the period of observation (4 days after removal). On the other hand, ginsenoside Rh1 does not inhibit the growth of melanoma cells even at concentrations over 100 microM but stimulates the expression of the melanotic phenotype. Ginsenosides Rh1 and Rh2, possessing a glucose molecule at C-6 and C-3, respectively, have very similar chemical structures, but their effects on B16 melanoma cells differ remarkably. While it appears that the degree of differentiation is inversely related to cell growth, the present observations suggest that the differentiation and growth capacity of this B16 melanoma subline are independent phenotypic expressions.

Animals↗

Stability kinetics of ginsenosides in aqueous solution.

The stability of ginsenosides (Rb1, Rb2, and Rg1) in aqueous solutions of varying pH was studied kinetically at 37 degrees C and an ionic strength of 0.15, using reverse-phase high-performance liquid chromatography. Degradation readily occurred by a proton-catalyzed reaction, the half-lives being only approximately 30 min at pH 1. However, under neutral intestinal pH conditions, the degradation was almost negligible throughout the experimental period (approximately 40 h).

Drug Stability↗

Induction of digestive-tract tumors in F344 rats by continuous oral administration of N-butyl-N-nitrosourea.

Male and female F344/DuCrj rats were administered N-butyl-N-nitrosourea at a concentration of 400 ppm in their drinking water. By the 50th week of the experiment, the cumulative incidence of upper-digestive-tract tumors was as high as 35/39 (90%) and 34/39 (87%) in male and female rats, respectively. Among these, esophageal and forestomach tumors occurred most frequently. Except one female rat with fibroma, upper-digestive-tract neoplasms were of the epithelial type -- papilloma, squamous-cell carcinoma or adenocarcinoma. In female rats, vaginal tumors were induced in 16 (41%) animals. Ear-duct tumors and hematopoietic neoplasms were also induced in both sexes of rats, with incidence of less than 21%.

Adenocarcinoma↗

Development of thymic lymphomas by oral administration of N-nitroso-N-propylurea and establishment of transplantable lines of thymic lymphoma in F344 rats.

Forty-eight female F344/DuCrj rats were given a 400-ppm solution of N-nitroso-N-propylurea (CAS: 816-57-9) continuously in their drinking water. Thymic lymphomas were induced most frequently (85%) followed by duodenal tumors (48%). Sixteen tumors were examined by the immunofluorescence inhibition test for murine leukemia virus-related antigens; 15 were negative and the other was weakly positive. Twenty-six tumors were intraperitoneally and subcutaneously transplanted syngeneically; 25 (96%) were successfully transplanted intraperitoneally and 24 (92%) subcutaneously. The serial intraperitoneal transplantation was continued, and 22 lines of transplantable lymphoma in an ascites form were established. In almost all tumor lines, tumor cells took in a high percentage of recipient rats and caused the death of the recipients within 12-23 days. The thymus, liver, spleen, greater omentum, and lymph nodes were frequently invaded by transplanted tumor cells. The tumor lines were considered to be of T-cell lineage.

Administration, Oral↗

[A case of malignant clear cell hidradenoma of the skin presumably arising from adenoma].

A left parietal skin tumor showing rapid enlargement in a 33-year-old woman was excised. The cut surface of the skin revealed a whitish tumor 4 cm in diameter associated with a cyst formation. Histologically, the whitish tumor was mucinous carcinoma in which large clear cells were conspicuous. Because nests of clear cell hidradenoma (CCH) were seen in the cyst wall, this carcinoma was diagnosed as malignant CCH presumably arising from a part of benign CCH. Malignant CCHs are thought to be malignant from their onset. Those proved to have developed from benign CCHs like the present case are extremely rare.

Adenoma↗

Induction of tumors in the small intestine and mammary gland of female Donryu rats by continuous oral administration of N-carboxymethyl-N-nitrosourea.

The carcinogenicity of N-carboxymethyl-N-nitrosourea (CMNU), a naturally occurring N-nitroso compound, was tested in female Donryu rats. Four groups of female Donryu rats were given 400, 200, 100, or 0 ppm of CMNU solution continuously as drinking water. The incidence of tumors was highest and the mean survival time shortest in the 400 ppm group. A dose-effect relationship was observed in the tumor incidence and the mean survival time and the incidences of tumors in all experimental groups were significantly different from those in the control group. In the 400 ppm group, tumors were detected most frequently in the small intestine, followed by the mammary gland. In contrast, most tumors were observed in the mammary gland in the other two experimental groups, although dose-dependent induction of tumors of the small intestine was also detected in these two groups. The organ specificity of CMNU is compared with that of other N-alkyl-N-nitrosourea derivatives.

Animals↗

Carcinogenicity study of ammonia-process caramel in F344 rats.

The carcinogenicity of ammonia-process caramel, a food colouring, was examined in F344 rats. Caramel was dissolved in distilled water at levels of 0, 1 and 4% and groups of 50 male and 50 female rats were given 20-25 ml of one of these solutions/rat/day as their drinking water for 2 yr. There were no significant differences between the total incidences of tumours or mean survival times of control and experimental groups. A variety of tumours developed in all groups including the control group, and no dose-related effects were found either in the incidence or induction time of tumours in the various organs and tissues except in the pituitary gland of males, in which the incidence of tumours in males given 4% caramel solution was significantly higher than that in controls. Pituitary tumours are among the most common spontaneous tumours in ageing rats of this strain and have a variable incidence. In addition, almost all pituitary tumours detected in males given the 4% solution were microscopic tumours, and there was no significant difference between controls and treated groups in the incidence of hyperplasia or pre-neoplastic lesions in the pituitary gland. These results indicate that the significantly higher incidence of pituitary tumours in males given the 4% caramel solution was not related to caramel administration, but could be explained by the variability of the incidence of spontaneous pituitary tumours. Thus it is concluded that under these experimental conditions ammonia-process caramel was not carcinogenic in F344 rats.

Age Factors↗