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101.
Medaka fish (Oryzias latipes) were exposed to various doses of X-rays or fast neutrons, and the frequency of micronucleated cells (MNCs) was measured in gills sampled at 12- or 24-hr intervals from 12 to 96 hr after exposure. The resulting time course of MNC frequency was biphasic, with a clear peak 24 hr after exposure, irrespective of the kind of radiation applied and the dose used. The half-life of MNCs induced in the gill tissues by the two exposures fluctuated around 28 hr, with no significant dose-dependent trend for either X-ray- or neutron-exposed fish. As assayed 24 hr after exposure, the MNC frequency increased linearly over the control level with increasing doses of both X-rays and fast neutrons. The relative biological effectiveness (RBE) of fast neutrons to X-rays for MNC induction was estimated to be 4.3 +/- 0.6. This value is close to the RBE value of 5.1 +/- 0.3 reported for fast neutron induction of somatic crossing-over mutations in Drosophila melanogaster that arise from recombination repair of DNA double-strand breaks. These results and other data support our conclusion that the medaka gill cell micronucleus assay is a reliable short-term test for detecting potential inducers of DNA double-strand breaks. 相似文献
102.
103.
Masafumi Ito Kazuo Hara Shinsuke Saga Junpei Asai Soichi Iijima 《Pathology international》1988,38(12):1565-1573
We report two cases of acquired toxoplasmic lymphadenitis, one with toxoplasmic cysts and the organisms of Toxoplasma gondii and the other with the organisms only. These cysts and organisms were observed in paraffin-embedded sections, touch smears and ultrathin sections for electron microscopy. Touch smears were especially valuable for the quick and accurate diagnosis of toxoplasmic lymphadenitis. We also studied immature sinus histiocytosis (ISH) in these cases. The predominant cells of ISH were confirmed to be B lymphocytes immunohistochemically, the majority being positive for polyclonal surface IgM. ISH was observed in the perifollicular and paracortical areas surrounding post-capillary venules (PCV), whereas the sinuses were only partially involved. 相似文献
104.
Apoptosis with FasL+ cell infiltration in the periphery and thymus of corrected autoimmune mice.
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T Kobata K Takasaki H Asahara N M Hong K Masuko-Hongo T Kato S Hirose T Shirai N Kayagaki H Yagita K Okumura K Nishioka 《Immunology》1997,92(2):206-213
Fas (CD95) ligand (L) is a death factor that binds to its receptor, Fas, and induces apoptotic cell death, a crucial process in immunological tolerance. gld (generalized lymphoproliferative disorder) mice, which have a point mutation in the FasL gene, develop spontaneous systemic autoimmune syndromes characterized by hypergammaglobulinaemia and lymphoid hyperplasia owing to accumulation of abnormal B220+ CD3+ cells. Transplantation of wild-type (wt) bone marrow cells into old gld mice on the same strain background results in normalization of autoimmune syndromes. We characterized the cellular mechanisms (functionally and histologically) of the above phenomena in gld mice after bone marrow transplantation (BMT) to determine the role of apoptosis via Fas/FasL interactions in inducing and maintaining self-tolerance in vivo. Activated splenocytes from wt and BMT (wt to gld) mice showed significant cytotoxic activity against Fas transfectant cells while those from BMT (gld to gld) mice did not. Cells in the thymus, spleen and lymph nodes of gld mice uniformly upregulated Fas expression and were sensitive to Fas-mediated apoptosis compared with those in wt mice. Cells sensitive to Fas-mediated apoptosis in gld mice resided not only among abnormal B220+ CD3+ cells but also among conventional lymphocytes. More importantly, histological analysis revealed that cells in the spleen, lymph nodes and thymus frequently underwent apoptosis with infiltration of FasL+ cells in BMT (wt to gld) mice compared with BMT (gld to gld) mice. Our results indicated that apoptosis via Fas/FasL interactions can directly eliminate pathogenic cells responsible for autoimmunity in the periphery and possibly in the thymus in vivo. 相似文献
105.
Takanori Hirose Toshiaki Sano Junichi Abe Kazuo Hizawa Shigeki Hatakeyama Itsumi Mori 《Ultrastructural pathology》1988,12(5):529-536
A case of recurrent soft part sarcoma with focal areas showing epithelial differentiation in the right thigh in a 78-year-old woman is reported. The primary tumor consisted of myxoid areas and solid areas, in which relatively uniform epithelioid tumor cells were arranged in sheets, whereas pleomor-phism and a storiform pattern appeared in the recurrent tumors. Thus this tumor was suspected to be a malignant fibrous histiocytoma. However, further studies showed unexpected ultrastructural and immunohistochemical features. Cytokeratin immu-noreactivity and tonofilamentlike structures probably indicated epithelial differentiation of some tumor cells. From the clinical and histological findings, this tumor should be identified as a malignant fibrous histiocytoma with phenotypic expressions of epithelial cell. 相似文献
106.
Functional mapping of the activity of the R region in the human T-cell leukemia virus type I long terminal repeat to increase gene expression 总被引:3,自引:0,他引:3
We previously demonstrated the activity of the R fragment in the long terminal repeat of human T-cell leukemia virus type I for elevation of the level of gene expression. In this study, the fragment was deleted with BAL31 nuclease to determine its functional domain. Series of the shortened R fragments were linked to the simian virus 40 promoter unit, which regulated expression of a reporter gene. Examination with the R fragments deleted from the 5 and 3 ends showed that borders of the functional domain were mapped within nucleotide positions 458 to 473 for the 5 end and nucleotide positions 559 to 594 for the 3 end, respectively. Thus we conclude that a 136-base-pair fragment corresponding to the second half of the R region was sufficient to allow elevation of the level of gene expression. 相似文献
107.
Emiko Ono Yuji Maeda Hidenori Tanimoto Yuma Fukutomi Chiyako Oshikata Kiyoshi Sekiya Takahiro Tuburai Naomi Turikisawa Mamoru Otomo Masami Taniguchi Houta Ishii Akihiko Asahina Eishi Miyazaki Tosihide Kumamoto Kazuo Akiyama 《Arerugī》2007,56(6):587-592
BACKGROUND: Recently, it is recognized that the patients of oral allergy syndrome (OAS) to fruits are increasing. However, there are little knowledges of the background, character, and seriousness about these patients in Kanto regions. OBJECTIVE: We aimed to investigate the clinical features of OAS patients to plant origin foods in Kanto regions. METHODS: The patient, who visited Sagamihara National Hospital from 2000 to 2005 and developed some allergic symptoms to plant origin foods, were studied by a questionary survey. RESULTS: As for the 42 subjects, average age are 36 years old, male:female=8:34, merger of other allergic disease is 35 allergic rhinitis of 42 subjects (83%), 34 of asthma (81%), 14 of atopic dermatitis (33%). The causes of OAS symptoms are 32 rose-family fruits, 34 non-rose family fruits, 14 vegetables, 11 nuts, 2 grains subjects. As for the symptom, only in the oral and pharynx symptoms are found in 12, the systemic symptoms is 29, anaphylaxis is 11 subjects. Allergic rhinitis preceded on the 90% subjects with pollinosis, very high rate. On the other hand, the 20% of all subjects have no symptoms of allergic rhinitis. CONCLUSION: A nasal catarrh symptoms went ahead in most of the OAS subjects in Kanto regions. In addition, considering from some patients have no black alder pollinosis and/or are allergic to many non-rose-family fruits at high frequency, there might be a broad cross-reactivity between many pollens other than alder and plant origin foods. 相似文献
108.
Kawabata A Kawao N Itoh H Shimada C Takebe K Kuroda R Masuko T Kataoka K Ogawa S 《Neuroscience letters》2002,329(3):349-353
Activation of the peripheral protease-activated receptor-2 (PAR-2) triggers nociceptive behaviour and thermal hyperalgesia in rats. The present study created a novel mouse model for PAR-2-triggered nociception, and then examined the roles of NMDA receptors and the nitric oxide (NO) pathway in nociceptive processing by PAR-2. Intraplantar administration of the PAR-2 agonist SLIGRL-NH(2) elicited nociceptive responses in mice, an effect being more specific in mast cell-depleted mice. This PAR-2-triggered nociception was abolished by the NMDA receptor antagonist MK-801, but not the neuronal NO synthase inhibitor 7-nitro indazole. In contrast, the PAR-2-triggered thermal hyperalgesia in rats was blocked by both agents. Our study thus provides a novel mouse model for PAR-2-mediated nociception, and suggests that NMDA receptors are involved in PAR-2-triggered nociception and hyperalgesia, while NO contributes only to the latter. 相似文献
109.
Satoru Takahashi Tomoyuki Shirai Kumiko Ogawa Katsumi Imaida Chikao Yamazaki Akira Ito Kazuo Masuko Nobuyuki Ito 《Pathology international》1993,43(11):674-682
Step-sections of 96 whole kidneys from 50 chronic hemodialysis patients were subjected to a histopathological and quantitative investigation with regard to the development of renal neoplastic lesions. The range of hemodialysis duration was from 1 to 222 months. A total of 349 renal cell adenomas were found in 41 cases (82%). They were commonly multiple and present bilaterally. Renal cell carcinomas were evident in four cases (8%), with hemodialysis durations of 54, 57, 112 and 222 months. The incidence of adenomas increased in a hemodialysis duration-dependent manner, indicating a high risk of renal cell tumor development in chronic hemodialysis patients. Furthermore, acquired cystic disease of the kidney (ACDK) was also observed in 12 cases (24.0%), where the mean hemodialysis period was 143.4 ± 48.0 months. This value was significantly longer than that of non-ACDK cases (P < 0.001). There was, however, no clear relationship between the appearance of ACDK and renal cell tumors. The present results underline the necessity for attention to possible neoplasia of the kidney in patients on long-term hemodialysis. 相似文献
110.
Katsuhiko Aoyama Kazuo Terashima Yutaka Imai Noriko Katsushima Yoshio Okuyama Katsuhisa Niikawa Takeo Mukada Katsuro Takahashi 《Pathology international》1984,34(2):375-388
The present paper deals with immunohistochemical and ultrastructural study of the lymph nodes of sinus histiocytosis with massive lymphadenopathy (Rosai and Dorfman, SHML) of a 12-year-old Japanese boy. This is the fourth case in Japan. Osseous manifestation was also found in the bilateral ulnae. With hallmarks of S-100 protein and interdigitating cytoplasmic extensions, the phagocytizing histiocytes proliferating in the sinuses were considered to be derived mostly from interdigitating cells in the paracortex or T cell dependent area, which have heretofore been regarded as nonphagocytizing. Furthermore, it is most interesting that lymphoid cells bearing thymic cortical cell-antigen (OKT 6) were increasingly recognized in the patient's peripheral blood. These results suggested that SHML is a specialized reactive histiocytosis analogous to histiocytosis X and histiocytic medullary reticulosis. 相似文献