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Biomedical subjects

T Kodama

Publications and source records attributed to T Kodama.

At least 1,063 records · Page 59Linked to original sources
PubMed1976

Sodium-dependent growth and respiration of a nonhalophilic bacterium, Pseudomonas stutzeri.

Pseudomonas stutzeri (van Niel strain) requires Na+ for growth. Its growth rate was a sigmoidal function of Na+ concentration, being maximal and constant from 2 to 50 mM-Na+, and half maximal at about 0-5 mM-Na+. The relationship between cell concentration and Na+ concentration was non-linear; cell concentration increased abruptly when Na+ was greater than 0-3 mM. Accumulation of Na+ in the organism during growth was not detected. In the presence of K+, respiration was enhanced specifically by Na+. The respiration rate of the organism growing in the culture was a linear function of the growth rate when limited by the Na+ concentration, whereas the maximum rate induced by excess Na+ was independent of the growth rate.

Oxygen Consumption↗
PubMed1976

Effect of lyophilization and storage of liver 9,000xg supernatant fraction on the metabolism of imipramine in several species of animals.

Effects of lyophilization and storage of liver 9,000xg supernatant fraction on the activity of drug metabolizing enzymes in some species of animals were studied. Imipramine metabolizing enzyme activity and the content of cytochrome P-450 were stable for, at least, one month without any loss of the activity when lyophilized liver 9,000xg supernatant fraction of some animal species, i.e., rat, mouse, guinea pig, rabbit and dog, was stored under reduced pressure in a deep freezer (-20 degrees C). There were no differences of imipramine metabolism between lyophilized liver 9,000xg supernatant fraction which was kept in a deep freezer for one month and a fresh fraction which was prepared immediately before determinations of the enzyme activity and cytochrome P-450. The data presented here indicated that the lyophilized preparation of the liver 9,000xg supernatant as well as the fresh preparation can be used for the determination of the drug metabolizing enzyme activity.

Animals↗
PubMed1976

Adoptive immunotherapy of a Gross virus producing lymphoma and a methylcholanthrene-induced fibrosarcoma in tolerant rats.

Immunological tolerance to Gross virus-specific transplantation antigens in rats given neonatae transfer of donor lymphoid cells beneath the kidney capsule of syngeneic recipient rats. Immune or normal donor cells invariably developed a cell-mediated immune reaction in kidneys of GV-tolerant recipients, presumably against GV antigens present on the surface of recipient lymphoid cells in the kidney. Spleen and lymph node cells from tolerant rats failed to develop a reaction in tolerant recipients, but developed a strong reaction to histoincompatible antigens in the kidneys of semisyngeneic tolerant rats. The immunologically tolerant state in the rats could be broken by adoptive transfer of spleen and lymph node cells from syngeneic rats immunized with GV-induced lymphoma cells. Immunotherapy of a GV-induced and also a GV-infected methylcholanthrene-induced fibrosarcoma growing in tolerant rats was successful when immune spleen and lymph node cells were administered i.p. 3 days after s.c. inoculation of 2 X 10(7) tumor cells in the case of the lymphoma, and 1 day after inoculation of 5 X 10(6) tumor cells in the case of the fibrosarcoma.

AKR murine leukemia virus↗
PubMed1976

Xenogenization of rat erythroid cells by lymphatic leukemia virus: its role in induction of autoimmune hemolytic anemia.

Newborn rats given injections of low doses of Friend lymphatic leukemia virus subsequently developed hemolytic anemia characterized by production of antierythrocyte autoantibody. Electron microscopy showed C-type virus particles budding from the cell membrane not only of lymphoid cells but also of erythrocyte percursor cells in bone marrow and spleen, suggesting that the erythroid cells were infected by the virus. In addition, erythrocyte precursor cells expressed virus-induced cell surface antigens detected by cytotoxicity tests. Normal syngeneic rats preimmunized with a Friend lymphatic leukemia virusinduced tumor and subsequently inoculated with bone marrow, spleen cells, or reticulocyte-rich fraction derived from other rats injected with high doses of the virus at birth produced cytotoxic antibody to the virus-induced tumor and antierythrocyte autoantibody. In contrast, rats subsequently inoculated with virus-infected thymus or lymph node cells produced cytotoxic antibody but not antierythrocyte autoantibody. These results indicate that "xenogenization," previously shown for tumor cells and normal lymphoid cells, is also observed for rat erythroid cells and, further, that xenogenization of erythroid cells by Friend lymphatic leukemia virus is one of the most important factors in induction of autoimmune hemolytic anemia.

Anemia, Hemolytic, Autoimmune↗
PubMed1976

Primitive hypoglossal artery associated with basilar artery aneurysm.

A case of persistent primitive hypoglossal artery, accompanied by a basilar bifurcation aneurysm, is reported. The persistent primitive hypoglossal artery was seen on the right side and the left vertebral artery was hypoplastic. The right vertebral artery was absent, while a normal sized posterior communicating artery was seen on the right side at the operation on the aneurysm. The combination of a basilar bifurcation aneurysm and a persistent primitive hypoglossal artery is rare. A review of related reports has been made.

Adult↗
PubMed1975

Hormonal status of breast cancer. II. Abnormal urinary steroid excretion.

The urinary excretion of 14 neutral steroids was measured by gas-liquid chromatography in women with early and advanced breast cancer, in women with early uterine cancer, and in healthy women from urban and rural districts. The premenopausal patients with early breast cancer excreted subnormal amounts of five steroids (11-hydroxyandrosterone, 11-hydroxyetiocholanolone, pregnanediol, pregnanetriol, and tetrahydrocorticosterone) and increased amounts of tetrahydrocortisol as compared with the normal subjects of corresponding ages. From our findings, a new parameter was proposed by which a premenopausal breast-cancer patient was separated from the control. Postmenopausal breast-cancer patients excreted greater amounts of five steroids (one steroid from 17-ketosteroids and four from 17-hydroxycorticoids) than the corresponding controls. The discrepancy between premenopausal and postmenopausal breast cancer was tentatively related to ovarian-adrenal dysfunction in the course of aging. Oophorectomy induced a long-lasting tumor regression only in patients with a high value for the ratio of 11-deoxy-17-ketosteroid to 17-hydroxycorticosteroid in urine taken before surgery; the ratio in the responsive patients decreased remarkably after surgery. A constitutional change in 17-ketosteroids, as observed in a postmenopausal breast-cancer patient and a premenopausal healthy woman of urban origin, favored the geographic importance in the genesis of breast malignancy. The steroid abnormalities in uterine cancer were distinguishable from those of breast cancer in both premenopausal and postmenopausal women.

11-Hydroxycorticosteroids↗
PubMed1975

The relationship of gastrointestinal endocrine cells to gastric epithelial changes with special reference to gastric cancer.

Using advanced gastric adenocarcinoma and carcinoid as human material and gastric adenocarcinoma in rats induced by MNNG and in mice by localized X-irradiation of the stomach as experimental material, a pathological study was made on the relationship of gastric endocrine cells to gastric cancer. The results of the present study suggest that most of the endocrine cells in the cancer tissue are derived from the differentiation of cancer cells. Therefore, the following three may be given as the aformentioned relationship, that is, 1) carcinoid of endocrine cell origin, 2) endocrine cell carcinoma showing undifferentiated adenocarcinoma, and 3) endocrine cell cloning developed from the differentiation of cancer cell of adenocarcinoma. There is the possibility that most of 2) are of 3) origin and thus 2) and 3) should be discriminated from 1), having a functioning tumor in rare cases. The significance of reactive hyperplasia of endocrine cells in the non-metaplastic mucosa of the stomach around cancer and atypical epithelium is not yet determined, but that of EC cell seems at least to be related with the development of intestinal metaplasia in the gastric mucosa.

Adenocarcinoma↗
PubMed1975

Enhancing effect of hydrocortisone on hematogenous metastasis of Ehrlich ascites tumor in mice.

The effect of hydrocortisone on blood-borne tumor metastasis was studied in an i.v. inoculation experiment with Ehrlich hypotetraploid clone 1, Ehrlich hypotetraploid stock, and Ehrlich hyperdiploid stock tumors. The administration of hydrocortisone before tumor inoculation resulted in increased tumor take, reduced mean survival time of mice, and concentration of tumor metastasis in a specific organ (i.e., lung metastasis for Ehrlich hypotetraploid clone 1 tumor, and liver metastasis for Ehrlich hypotetraploid stock and Ehrlich hyperdiploid stock tumors). Enhancement of tumor metastasis, as induced by hydrocortisone pretreatment, was not reproduced by the administration of 6-mercaptopurine, testosterone, or estradiol. The progress of tumor death in hydrocortisone-conditioned mice was not affected by either heparin or dextran sulfate. This indicated that the effect of hydrocortisone on tumor metastasis was independent of the effect of these agents on immune reaction or blood coagulation. In the tracer experiment with 125-I-labeled tumor cells, hydrocortisone pretreatment significantly increased over the control the intrapulmonary retention of Ehrlich hypotetraploid clone 1 tumor cells from 1 through 72 hr after tumor inoculation, the time lag required for the establishment of metastatic foci in the lung. The arrest of Ehrlich hypotetraploid stock and Ehrlich hyperdiploid stock tumors in the liver was also temporarily increased by hydrocortisone pretreatment. No correlation was found between tumor cell size and differential distribution of metastatic tumors with 3 Ehrlich tumors. An attempt was made to use this blood-borne metastasis system for chemotherapeutic study. Administration of cyclophosphamide gave rise to a significant prolongation of survival time and often to complete prevention of tumor metastasis in hydrocortisone-conditioned mice.

Animals↗
PubMed1975

Inhibition of metastasis in rats immunized with xenogenized autologous tumor cells after excision of the primary tumor.

Subcutaneously transplanted 3-methylcholanthrene-induced KMT-17 tumor in WKA rats yielded not only a local solid tumor but also frequent metastases in regional lymph nodes. Neither active immunization with xenogenized identical tumor cells nor surgical excision of the solid tumor prohibited the metastases when each treatment was given 4 days after tumor transplantation. However, immunization combined with surgery significantly decreased the metastases and prolonged survival.

Animals↗
PubMed1975

Hormonal status of breast cancer. I. Thoretical basis for the analysis of steroid profile.

Gas-liquid chromatography was applied to the analysis of urinary steroids of women. In the statistical analysis, quantitation of all steroid excretions and ratios among them were transformed to give a normal frequency distribution. The influence of the host's age and the menstrual cycle on 24 hours' excretion was investigated for each of 14 identified neutral steroids, of which four in our fraction 2 (11-hydroxyandrosterone, 11-hydroxyetiocholanolone, pregnanediol, and pregnanetriol) were menstruation dependent. The 14 neutral steroid excretions were generally correlated with one another within the host, and the use of a steroid ratio rather than quantitation of steroid excretion was often more sensitive in the characterization of the hormonal status.

11-Hydroxycorticosteroids↗
PubMed1975

Histopathology of regression of tumor metastasis in the lymph nodes.

A transplanted rat lymphosarcoma (SGT-4), induced by Gross virus and inoculated s.c. into the foot of a normal syngeneic rat, initially grew but ultimately regressed. The tumor cells metastasized to the regional popliteal, lumbar, and inguinal lymph nodes and formed massive metastatic foci there. These lymph node metastases also regressed spontaneously. However, in Gross-tolerant rats inoculated with Gross virus at birth, no regression was observed. Histopathologically, infiltration and proliferation of lymphoid cells, reticulum cells, and bifrocytes occurred in the regressing metastatic tumor in lymph nodes as well as in the regressing transplanted tumor in the foot. Only in lymph nodes of normal rats, in which tumor metastasis regressed, was the characteristic "starry sky" appearance observed. Our results suggest that regression of metastatic tumor in lymph nodes, as well as of transplanted tumor in syngeneic rats, was due to an immunological reaction by the host and that an immunological factor may be responsible for the "starry sky" picture.

AKR murine leukemia virus↗
PubMed1975

[Studies on cyclic 3', 5'-AMP system in human brain and its clinical application in Neurosurgical practice (author's transl)].

Literatures showed that cyclic AMP of cultured neoplastic cells of any kind was very low in concentration and also the effect of cyclic AMP and its derivatives on the malignant cells, especially on the malignant glioma, was already reported in vivo or in vitro from several neurosurgical units. The intrinsic content of cyclic AMP of the human cerebrum and the human brain tumors was first reported by authors in 1971. In this presentation the authors intended to confirm that the lower concentration of the cyclic AMP the more histologically malignant cerebral neoplasm, as well as in the cerebrospinal fluid, was observed. Concentration of cyclic AMP in the subcortical white matter, glioma, meningioma and medullobalstoma was much lower than in the gray matter tissue, however, it was not clear that the difference of the cyclic AMP concentration be possibly related to the malignancy of the human brain tumor. Furthermore, the cyclic AMP content of the cerebrospinal fluid of the patients with various brain tumor was not clearly different. The activity of adenyl cyclase was reported the highest in the synaptosome-containing fraction of the rat brain homogenate and this fact was significantly consistent with the finding that the highest concentration of the cyclic AMP was found in the human grey matter tissue. With the human brain gray matter authors determined successfully the activity of the human cerebral phosphodiesterase, which was probably localized in the post-synaptic membrane and was 158 nmole/mg protein/min. Its apparent Km was 0.9 x 10(-4) M. The results reported above have suggested the important participation of the cyclic AMP to cerebral synaptic transmission of nerve impulses, which was studied by light and electron-microscopic autoradiography utilizing the pulse labeling method with 3H-adenine. According to our study the majority of the adenyl cyclase of the human cerebrum was located synaptic structure and the finding obtained was quite compatible, as the first morphological study, with previously reported biochemical analyses. It was indicated that the cyclic AMP in the human brain was concerned to the cerebral synaptic transmission of nerve impulses and this should be very interesting and important to the clinical application for recovering cerebral function of neurosurgical patients.

2',3'-Cyclic-Nucleotide Phosphodiesterases↗