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Biomedical subjects

Y Odagiri

Publications and source records attributed to Y Odagiri.

At least 37 records · Page 2Linked to original sources
PubMed1989

Negative micronucleus tests on caprolactam and benzoin in ICR/JCL male mice.

Male ICR/JCL mice were given a single intraperitoneal injection of 125, 250, and 500 mg/kg of caprolactam (CAP), or 250, 500, and 1000 mg/kg of benzoin (ZOIN). Bone marrow preparations were made 24, 30, and 48 h after treatment with the maximum dose, and 30 h after treatment with the other doses. The slides were coded before microscopic examination. No significant increase was found in the incidence of micronucleated polychromatic erythrocytes after treatment with either CAP or ZOIN.

Animals↗
PubMed1986

Carcinogenic effects of a mixture of nitropyrenes in F344 rats following its repeated oral administrations.

The carcinogenic effects of a mixture of 1-nitropyrene and three dinitropyrenes (1,3-, 1,6- and 1,8-dinitropyrene) were investigated in rats. Female F344/Jcl rats were given one of three doses (5, 10 and 20 mg/kg body weight) of the mixture by repeated intragastric instillations twice a week for 55 weeks, and then autopsied 49 weeks later. Mammary adenocarcinomas were induced in rats of all the three experimental groups dose-dependently, while no adenocarcinoma was induced in the control rats which were given only vehicle. Clitoral gland tumors, most of which were diagnosed as squamous cell carcinomas, were also commonly observed in the NP-treated rats in a dose-dependent way. In addition, high incidences of mononuclear cell leukemias were noted in the NP-treated rats. Other tumors were frequently induced in the uterus and endocrine organs, such as the pituitary, adrenal, and thyroid glands. However, the incidences of these tumors were almost equal in both the control and NP-treated groups. The results of the present study indicated the potential carcinogenic activities of nitropyrene compounds in female rats when they were treated by oral route, and suggest that the oral intake of nitropyrene compounds might be related to the incidence of cancer in humans.

Administration, Oral↗
PubMed1984

Histopathological effect of botulinum C2 toxin on mouse intestines.

Botulinum C2 toxin has histopathological activity in the mouse intestine and induces fluid accumulation in intestinal loops. The toxin caused degenerative and necrotic changes in the intestinal mucosa: intracellular vacuolization of epithelial cells, desquamation and necrosis of the villous epithelium, intercellular edema, and infiltration of lymphocytes and histiocytes. The detectable changes in the morphology of the intestinal mucosa preceded the increase in fluid accumulation in intestinal loops. Intraluminal injection of botulinum C2 toxin also induced the leakage of plasma protein into the intestinal lumen as determined by the extravasation of Evans blue. In contrast to botulinum C2 toxin, cholera and Clostridium perfringens enterotoxin controls caused a very slight protein leakage, although these toxins induced marked fluid accumulation in intestinal loops. The results indicate that the mode of action of botulinum C2 toxin in eliciting the secretory response is distinguishable from those of cholera and C. perfringens enterotoxins and suggest that botulinum C2 toxin induces the secretory response by cytopathic effect(s) on the epithelial cells of the intestine.

Animals↗
PubMedDate not supplied

Detection of the cytogenetic effect of inhaled aerosols by the micronucleus test.

The induction of micronuclei in mice exposed to aerosols of the following 6 genotoxic chemicals by inhalation was examined: cyclophosphamide (CP), methyl methanesulfonate (MMS), mitomycin C (MMC), dimethylnitrosamine (DMN), ethylcarbamate and colchicine. Exposure of mice to CP aerosols at a theoretical concentration of 2426 mg/m3 for 29, 81 and 139 min induced 0.6, 1.0 and 2.3% micronucleated polychromatic erythrocytes (MNPCEs) in bone marrow 24 h after the termination of exposure. The other chemicals except for DMN showed a similar exposure-response relationship following in vivo exposures to their aerosols. The results obtained in this study suggest that the cytogenetic effect of inhaled aerosols can be detected by the micronucleus test, and the method described in the present report is useful as a rapid in vivo test for atmospheric aerosols.

Aerosols↗
PubMedDate not supplied

Damage to lymphocytes by X-ray and bleomycin measured with the cytokinesis-block micronucleus technique.

Chromosome damage induced by X-irradiation or bleomycin was measured using the cytokinesis-block micronucleus assay in the peripheral blood lymphocytes of 6 newborn, 8 young and 10 elderly individuals. An increase in the frequency of spontaneous micronuclei with age was observed. There was no difference in the X-irradiation-induced micronucleus frequency between the 3 groups. There was a significant increase with age in the number of micronuclei induced by bleomycin. Kinetochore-labelling studies revealed that the percentage of kinetochore-positive induced micronuclei was higher for bleomycin (36.2-43.3%) than for X-irradiation (17.1-19.7%). The age-related increase in frequency of spontaneous or bleomycin-induced micronuclei was due to increases in both kinetochore-positive and kinetochore-negative micronuclei. The frequency of kinetochore-positive or -negative micronuclei induced by X-irradiation was not different between the 3 age groups. These results suggest that bleomycin is more potent in inducing whole-chromosome loss than X-rays, and that lymphocytes from aged individuals are more sensitive to bleomycin in terms of both chromosome breakage and whole chromosome loss.

Adult↗
PubMedDate not supplied

Pathologic changes in chickens caused by intravenous inoculation with fowlpox virus.

Twenty chickens were inoculated intravenously with fowlpox (FP) virus, and clinical and pathological examinations were carried out chronologically. Upon gross examination, miliary nodules scattered in the kidneys were observed from 10 to 18 days postinoculation (PI), as were papules on the skin and diphtheritic lesions on the mucous membrane of the upper respiratory tract. Microscopically, characteristic FP lesions, composed of swelling and proliferation of cells with formation of Bollinger bodies, were observed in the epithelial cells of renal tubules from 4 to 14 days PI and in the epithelial reticular cells of the thymic medulla from 4 to 10 days PI, as well as in the skin and mucous membrane. Immunofluorescent and electron microscopic observations confirmed the presence of viral antigen and virus particles in the characteristic lesions of FP.

Animals↗
PubMedDate not supplied

Pathological changes of tracheal mucosa in chickens infected with lentogenic Newcastle disease virus.

Forty-day-old specific-pathogen-free chickens were exposed by aerosol to lentogenic Newcastle disease virus (NDV) and observed for 24 days for pathological changes in the tracheal mucociliary system. Specific fluorescence of NDV antigen was observed through day 5 postexposure (PE) in the cytoplasm of the tracheal epithelium and desquamated epithelium in the lumen. On day 1 PE, scanning electron microscopy revealed hypertrophy of goblet cells and small patches of the deciliated epithelium scattered mainly around the openings of mucous glands. The deciliated area of tracheal surface increased through day 4 PE. Light microscopy showed small vacuoles containing lymphocytes and heterophils in the epithelial layer. Immature epithelium proliferated in some areas. On days 5 and 6 PE, ciliated areas of the trachea tended to increase as a result of regeneration of the epithelium, still leaving many nonciliated patches of various sizes. On and after day 8 PE, there remained plaques with nonciliated flat epithelium, but most areas were covered with well-ciliated epithelium. Non-ciliated plaques were observed until day 24 PE, but they gradually decreased in size. These plaques were covered by a single layer of flat epithelium and were formed upon lymph follicles in subepithelial tissue.

Animals↗