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Biomedical subjects

N Ohsawa

Publications and source records attributed to N Ohsawa.

At least 181 records · Page 10Linked to original sources
PubMed1979

Serum estradiol and radial mineral content in postmenopausal females.

The serum estradiol concentration and bone mineral content of the right radius were determined in 34 postmenopausal females. Regression analysis showed a significant positive correlation between the serum estradiol concentration and bone mineral content of the right radius (r=0.477, p less than 0.01). These results support the view that the decreased level of serum estrogens is one of the major factors involved in the loss of bone mass with age.

Aged↗
PubMed1979

Amplification of growth inhibition by glucocorticoid on L5178Y and L1210 lymphoblasts in vivo.

One component of a factor in Proteus mirabilis (Factor 1) which specifically amplifies the induction of several liver enzymes by glucocorticoid in target cells also increases the growth inhibition of glucocorticoid on the ascitic form of L1210 cells and solid tumors of L5178Y lymphoblasts in vivo. The growth of L5U78Y and L1210 lymphoblasts was inhibited by a triamcinolone acetonide dose of over 0.5 to 1.0 mg/kg body weight. Factor 1 increased the inhibitory effect of a triamcinolone acetonide dose of less than 4.0 mg/kg bodyweight but had little effect on the effects of doses of over 4.0 mg. Factor 1 (10 biological units/kg body weight) itself also caused marked inhibition of the growth of these lymphoblasts without affecting the body weight or adrenal gland weight, its effect being equivalent to that of 3- to 4-mg/kg body weight doses of triamcinolone acetonide alone. There was no significant difference in the level of plasma total corticoids or that of plasma adrenocorticotropic hormone between rats treated with 0.9% NaCl solution or those treated with Factor 1, and Factor 1 had no cytotoxic effec on cultured L5178Y lymphoblasts. Thus, Factor 1 may amplify the effect of physiological level of glucocorticoid in mice sufficiently to inhibit the growth of these lymphoblasts without causing any significant side effects to the host animal.

Adrenal Cortex Hormones↗
PubMed1979

Immune elimination of host fibroblasts for the cultivation of human tumors transplanted into nude mice.

We report here a useful method for the isolation and cultivation of human tumor cells in vitro from human tumors grown in nude mice. A rabbit was immunized with spleen cells obtained from adult nude mice. The rabbit antiserum in the presence of complement effectively killed cultured cells derived from various mouse tissues, but it was not cytotoxic to cultured cells from human tissues including tumors. When mixed cultures consisting of human tumor cells and nude mouse fibroblasts were treated with the antiserum and complement, the nude mouse fibroblasts were completely removed from the cultures, and the human tumor cells could be propagated without noticeable changes in morphological features. Primary cultures of heterotransplanted human tumors grown in nude mice were also successfully treated, resulting in the ultimate elimination of fibroblastic cells derived from the stroma of the tumor. The functional properties of the tumor cells (production of human chorionic gonadotropin by choriocarcinoma cells and production of carcinoembryonic antigens by pancreas carcinoma cells) were also maintained after the antiserum treatment.

Animals↗
PubMed1978

Establishment and characterization of a human cancer cell line that produces human colony-stimulating factor.

A human colony-stimulating factor (CSF) producing cell line, T3M-1, has been established from explant cultures of a human squamous cell carcinoma of the oral cavity that secretes human CSF. It has been continously propagated during the past 15 months. The cells grew in a monolayered sheet with about 17 hr of population-doubling time and showed a colony-forming capacity with about 5% plating efficiency. The cells exhibited an epithelioid morphology resembling the structure of the original tumor, and they showed "tumor takes" when inoculated into nude mice. Karyotypic analysis revealed the cell line to be a human aneuploid one with a hypotriploid mode, including the Y-chromosome(s) and at least 10 common markers. T3M-1 cells possess the characteristic function of human CSF production in vitro, and a marked neutrophilia was observed in nude mice bearing the tumors produced by inoculation with the T3M-1 represents a new human cell line that secretes human CSF.

Animals↗
PubMed1977

[Regulation of hormone receptor (author's transl)].

The regulation of hormone receptors is exerted through genetic and environmental factors. Genetic control of hormone receptors is analyzed by studying changes in their characteristics during the ontogeny, phylogeny, and malignant transformation of cells. The pattern of changes in glucocorticoid receptor contents in cytosol fraction during ontogeny is quite different from tissue to tissue. In the rat's lung tissue, glucocorticoid receptor contents are high during the fetal period and decrease promptly after birth, whereas the contents in the rat's liver are low during the fetal life and start to increase after birth. Glucocorticoid receptors in thymocytes of rats during T-cell differentiation increase transiently, which gives a high sensitivity to steroid treatment in the immature thymocytes. The induction of glucocorticoid receptors in different tissues at different stages of life is strictly controlled by the genetic program. Whether the induction is mediated by humoral factor(s) remains to be clarified. Amounts of glucocorticoid receptors in a particular tissue are subjected to species differences. In a group of steroid-sensitive animals such as the rat, mouse, rabbit and hamster, the amount of glucocorticoid receptors in liver sytosol is rich, whereas it is poor or undetectable in a group of steroid-resistant animals, such as the human, monkey, dog and guinea-pig. Changes in hormone receptors are also observed in malignant tumors. Under certain circumstances, hormone receptors "appear" in malignant tumors originated from organs in which no detectable hormone receptor is observed. These tumors may be called hormone receptor-producing tumors. Environmental factors are also important in regulating hormone receptors. Down regulation of hormone receptors is observed in insulin and glucocorticoids.

Animals↗
PubMed1977

Radioimmunoassay for etiocholanolone.

A sensitive and reliable radioimmunoassay for serum unconjugated etiocholanolone (3alpha-hydroxy-5beta-androstan-17-one) is reported. The antiserum was obtained from rabbits by immunization of etiocholanolone-17-(O-carboxymethyl) oxime [CMO]-bovine serum albumin [BSA]. Two ml of serum with 3H-etiocholanolone added for recovery was extracted with ether, and etiocholanolone was separated from cross-reacting steroids by Sephadex LH-20 column chromatography. The mean recovery after extraction and chromatography was 80.7 +/- 6.8 (S.D.)%. The sensitivity of the assay was less than 40 pg. The intraassay and interassay coefficients of variation were 9.2% and 10.9%, respectively. The mean of serum unconjugated etiocholanolone concentration determined by the present method was 0.39 +/- 0.10 (S.D.) ng/ml (n = 50) in normal men and 0.36 +/- 0.08 (S.D.) ng/ml (n = 20) in women in the follicular phase of the menstrual cycle.

Adult↗
PubMed1977

A radioreceptor assay for insulin: direct measurement of dog pancreatic vein serum insulin.

A simple radioreceptor assay for insulin rat liver membranes as receptor sites, with sufficient specificity precision, and sensitivity to detect 10 ng or 276 muU/ml of serum insulin, has been developed. In the presence of standard porcine insulin at the concentration of 1.0 ng/tube, approximately 8% of 125I-porcine insulin was bound to the plasma membranes and ninety-five per cent of this binding was inhibited by 1.0 microgram of standard insulin per tube. Four animal insulins inhibited the binding of 125I-insulin while ACTH, glucagon, human growth hormone, and oxytocin were inert. Insulin values in dog pancreatic vein sera obtained during and after glucose loading and measured by the present radioreceptor assay agreed well with immunoreactive insulin. The ratio of IRI to the measurement by radioreceptor assay was 1.09 +/- 0.18 for the same sera.

Adrenocorticotropic Hormone↗
PubMed1977

Extremely high levels of corticosteroids and low levels of corticosteroid binding macromolecule in plasma of marmoset monkeys.

Marmoset monkeys were shown to have extremely high resting plasma corticosteroid levels compared to those of macaque monkeys and humans. A major component of corticosteroids seems to be cortisol. Levels of total 11-deoxy-17-KS in plasma of marmoset monkeys were very low (less than 0.01-0.04 microng/ml). Following the injection of ACTH, plasma corticosteroid levels of marmoset monkeys increased by 18-62% (at 1 h), and by 62-160% (at 2 h). Concentrations of plasma corticosteroid binding macromolecule in marmoset monkeys were extremely low (less than 10 nM). It was suggested that in these monkeys, the majority of plasma corticosteroids exists in non-protein bound forms.

Adrenal Cortex Hormones↗
PubMed1977

Frozen preservation of human malignant tumors transplanted into nude mice.

Five transplantable tumors, which originated from human maligant neoplasms and had been maintained in nude mice, were frozen at--70 degrees preserved for 1226 days. Tumor tissue was minced in a mixture of tissue culture medium, 10% dimethyl sulfoxide, and 10% calf serum before freezing. The transplantability of frozen tumors was examined after thawing. Morphological and functional characteristic of each tumor were compared before and after the frozen storage. The results suggest that low-temperature preservation technique can be applied satisfactorily for the maintenance of human malignant tumors which have been maintained by using nude mice.

Animals↗
PubMed1976

Human gastric choriocarcinoma serially transplanted in nude mice.

A gastric choriocarcinoma cell line capable of producing human chorionic gonadotropin (HCG) was studied by sc transplantation and serial passages into nude mice fed under specific pathogen-free (SPF) conditions. The tumor-take rate at the serial heterotransplantation in SPF mice was high (greater than 95%), in contrast with a low rate in coventional animals (35%). The restoration of morphology and function of the original neoplasm were exclusively verified in SPF mice. Multiple lung metastases were found in 2 animals. The production, storage, and excretion of HCG by tumor cells were confirmed by its high content in serum and cystic fluid in tumors and by its intracellular localization. The tumor cells also contained a specific placental alkaline phosphatase in their membranes. The cells were various trophoblastic types ranging from primitive cytotrophoblasts to typical syncytial cells. The hormone effects of the tumor on sex organs of tumor-bearing animals were evident.

Alkaline Phosphatase↗
PubMed1976

Ascites form of a human cancer serially transplantable in nude mice.

Human adenocarcinoma cells injected into the peritoneal cavities of BALB/c nude mice (nu/nu) induced ascites carcinoma. The inoculant was obtained from subcutaneous tumors produced in nude mice by an injection of ascites cells from a patient with carcinomatous peritonitis caused by mucinous adenocarcinoma of the stomach. An ascitic fluid began to accumulate 45 days after inoculation and reached the maximum volume within 120 days. Dispersed stomach cancer cells in the ascites could be serially transplanted in nude mice in an ascites form. The morphology of these cells was similar to that of the original cells in the ascitic fluid of a patient with carcinomatous peritonitis.

Adenocarcinoma, Mucinous↗
PubMed1976

The effect of ACTH administration on serum estrogens, LH, and FSH in the aged.

The effect of administration of long acting ACTH on serum levels of estrogens, LH and FSH was studied in aged subjects. Nine women and 5 men between 66 and 90 years of age were examined. One milligram of long-acting synthetic ACTH was given in every 12 h for 2 days. Significant increases in serum estrone and estradiol levels were induced in parallel with serum cortisol at 24 hours and no further change was observed at 48 hours. The estrone/estradiol ratio increased from a control value of 3.0 to 4.0 at 24 hours and to 4.7 at 48 hours (P less than 0.02) compared to control values.

Adrenocorticotropic Hormone↗