Biomedical subjects
Publications and source records attributed to H Otsuka.
A new antibiotic designated tendomycin was isolated from the culture of Streptomyces No. 9034. The antibiotic is active against Gram-positive bacteria, fungi and cultured cancer cells, and shows an inhibitory effect of EHRLICH carcinoma in mice.
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The carcinogenicity of 1,2-dimethylhydrazine dihydrochloride (DMH) by oral, intragastric and subcutaneous administration was examined in 339 BALB/c mice. Subcutaneous injection of DMH induced intestinal tumors in the lower colon of all mice. After oral administration it induced a high incidence of vascular tumors in the liver and soft tissues, but colon tumors were found in only 2 mice when given at a high dosage. On intragastric administration, it induced a fairly high incidence both of colon and vascular tumors. The sites and incidences of vascular tumors and squamous cell carcinomas of the perianal glands were also described.
MKSA207 cells, a BALB/c mouse kidney line transformed by a tsA mutant of SV40, are temperature-dependent for the expression of the 'standard transformed phenotype'. At the permissive temperature (33.5 degrees C), the mKSA207 cells resembled wild-type (wt) SV40 transformants; they contained the intranuclear SV40 T antigen, grew to high saturation density in monolayer culture in either 10% or 0.5% serum, and also in methylcellulose suspension culture and became multinucleate in cytochalasin B. At the nonpermissive temperature (39.8 degrees C), the mKSA207 cells lost some of their transformed properties; they grew only to low density in 10% serum, hardly grew at all in 0.5% serum or in methylcellulose suspension culture, and remained mono- or binucleate in cytochalasin B. At 40 degrees C in low serum, mKSA207 cells lost the intranuclear T antigen and when fed 10% serum at 39.8 degrees C, accumulated large amounts of T antigen in the cytoplasm. Derivatives of mKSA207 have been selected at 39.8 degrees C in liquid medium and methylcellulose suspension culture. The heat adapted lines, like wt SV40 transformants, exhibited the standard transformed phenotype at both 33.5 and 39.8 degrees C. It is unlikely that acquisition of temperature-independence for the transformed phenotype was due to reversion of the tsA gene to wild-type because the heat-adapted cell lines displayed the cytoplasmic T antigen at 39.8 degrees C, characteristic of the parental mKSA207 cells and SV40 rescued from one of the heat-adapted lines was temperature sensitive for growth. The T antigen levels (complement fixation units per 10(6) cells) of heat-adapted lines grown at 39.8 degrees C were comparable to those of mKSA207 cells grown at 33.5 or 39.8 degrees C.
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The effect of 2-naphthylamine and cyclophosphamide on the urinary bladder and liver of female BALB/c mice was investigated. The bladder mucosa of mice treated with 2-naphthylamine alone for 40 weeks showed diffuse hyperplasia. Oral administration of 2-naphthylamine for 40 weeks plus injections of cyclophosphamide produced bladder carcinomas in 30.8 approximately 35.7% of all animals, associated with downward growth of the bladder epithelium. All the bladder carcinomas were of the transitional cell type and most of them contained pseudoglandular areas. Hepatomas seemed to develop in higher incidence in mice treated with 2-naphthylamine plus cyclophosphamide than in mice treated with 2-naphthylamine alone. Most of the hepatomas were solitary and showed a trabecular pattern. Cyclophosphamide seemed to have a summative or promoting effect on carcinogenesis of the bladder mucosa and liver induced by 2-naphthylamine in female BALB/c mice.
In order to elucidate whether basophilic cells in nasal secretion belong to blood basophil or tissue mast cell, basophilic cells in the blood, nasal secretion, and nasal mucous membrane were electron microscopically observed in patients with house dust nasal allergy. The majority of basophilic cells in the nasal secretion was identical with the blood basophil in structure. The blood basophils pass through the vessels and emigrate in the mucous blanket in allergy.
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A new pathway of NAD+ synthesis from anthranilic acid was found in the livers of rats. Starting from [carboxyl-14C]anthranilic acid, radioactive NAD+ and NADP+ were produced as judged by Dowex-1 X 8-formate column chromatography followed by radiochromatography. Several intermediate compounds, such as quinolinic acid, nicotinic acid mononucleotide, and nicotinic acid adenine dinucleotide were also identified with the aid of various chromatographic techniques. In the experiments with liver microsomal hydroxylation systems, anthranilic acid was converted into not only 5-hydroxyanthranilic acid but also 3-hydroxyanthranilic acid.
Evidences on the important role of tissue mast cells in inducing allergy have accumulated. There cells are known to be present in nasal secretion but have not been well studied. In the present study basophilic cells containing granules which stained metachromatically appeared in the nasal secretion in various kinds of inhalant allergy. An increase in their number was observed after nasal provocation and during the pollinosis season and showed a decrease after a course of immunotherapy or during the off-season of pollinosis. They were well correlated in degree with nasal symptoms, nasal eosinophilia, and nasal provocative reactions. These results suggest that the appearance of the basophilic cell in nasal secretion is related to their specifity in nasal allergy. The possibility of onset of nasal allergy due to the release of chemical mediators from basophilic cells in nasal secretion was discussed.
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Biological, histological, and ultrastructural studies were made on tumors produced in weanling hamsters inoculated with hamster embryo fibroblasts (HEF) transformed by herpes simplex virus type 2 or with cultured cells (tumor cell lines T1 and T2) derived from the tumor tissues. The malignancy of transformants increased through passages in vitro and in vivo. Histologically, two tumor cells lines (155-4T1 and U-15T1) produced fibrosarcomas and one (U-26T1) produced lesions resembling "malignant fibrous histiocytomas." Ultrastructurally, fibrosarcomas produced by 155-4T1 and U-15T1 consisted mainly of fibroblast-like cells with extracellular collagen fibers, whereas malignant fibrous histiocytoma-like lesions produced by U-26T1 consisted of undifferentiated cells, multinuclear giant cells, histiocyte-like cells, and fibroblast-like cells. Frequently, various kinds of "nuclear bodies" were found in the nuclei of tumor cells. Several herpes virus-like particles (120 approximately 140 nm in diameter) were detected in some nuclei of undifferentiated tumor cells produced by U-26T1.
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