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61.
Yasuhiro Amemiya Masamichi Katayama Susumu Harada 《Macromolecular chemistry and physics.》1977,178(9):2499-2505
Copolymers from 1,6-heptadiene ( 1 ) and SO2 with various mole ratios of their units were prepared. Their structures were studied by elemental analyses, IR and 1H NMR spectroscopy. Structures containing a cyclopentane ring ( 2 ) and such containing a thiane ring ( 3 ) in the main chain are proposed. 相似文献
62.
Immature dendritic cells (CD11c+ CD3- B220- cells) present in mouse peripheral blood 总被引:1,自引:0,他引:1
Adachi Y Toki J Ikebukuro K Tomita M Kaneda H Tanabe A Jun L Minamino K Suzuki Y Taketani S Ikehara S 《Immunobiology》2002,206(4):354-367
It is well known that dendritic cells (DCs) are developed from the peripheral blood of mice when peripheral blood mononuclear cells (PBMCs) are cultured with GM-CSF. We have previously found that immature DCs are present in the blood even in humans. In the present study, we show that CD11c+ CD3- B220- cells in the mouse peripheral blood are immature DCs. The percentage of CD11c+ CD3- B220- cells in the (PBMCs) of normal mice ranges from 0.5 to 2.5%. The CD11c+ CD3- B220- cells in the PBMCs show dendrites, similar in shape to the CD11c+ CD3- B220- cells in the spleen, which are thought to be DCs definitely. However, they have practically no capacity to stimulate the proliferation of allogeneic T cells, and show a lower expression of MHC class II, B7-1 and B7-2 than CD11c+ CD3- B220- cells in the spleen. When the CD11c+ CD3- B220- cells in the PBMCs are cultured with GM-CSF, they show not only the potent ability to stimulate the proliferation of allogeneic T cells but also a higher expression of MHC class II, B7-1 and B7-2. Moreover, they migrate into the spleen when they are injected intravenously. These results suggest that CD11c+ CD3- B220- cells in the PBMCs are immature DCs, and that they migrate into the spleen, where they mature. 相似文献
63.
Chronic active Epstein-Barr virus (EBV) infection has been recognized as clonal non-neoplastic lymphoproliferative diseases. However, some reports of cases with a multiphenotypic expansion of EBV-infected lymphocytes give rise to questions of how EBV infects multiphenotypic lymphocytes and whether chronic active EBV infection is a truly monoclonal lymphoproliferative disease. We report two patients with chronic active EBV infection who showed expansion of multiphenotypic EBV-infected lymphocytes. EBV DNA was detected in CD4+ and CD8+ T cells and in B cells from pleural fluid of one patient and in T and B cells from a cervical lymph node of the other patient by polymerase chain reaction (PCR). Although real-time PCR showed that there were equally high loads of EBV genomes in CD4+ and CD8+ T cells from the pleural fluid, Southern blot hybridization with terminal repeats of the EBV genome showed a single band of the same molecular weight in three tissue samples from the patient. The results indicated biphenotypic expansions of CD4+ and CD8+ T cells infected with the same clone of EBV. Furthermore, bisulfite PCR analysis showed hypermethylated status in the Cp region in the two patients regardless of their cell populations. There has been a discrepancy between clonality and expansion of multiphenotypic EBV-infected lymphocytes. We speculate that lymphoid progenitor cells that have not differentiated into T and B cell progenitors are infected with EBV, resulting in clonal expansion of EBV-infected multiphenotypic cells. 相似文献
64.
65.
Circadian rhythms of pineal melatonin release were measured in freely moving pigeons (Columba livia) by in vivo microdialysis. The birds were placed in light-dark cycles with 12 h of light and 12 h of darkness (LD 12:12) or continuous dim light (LLdim) after LD 12:12. Although the level of melatonin was various, daily changes of melatonin with higher levels during the dark and lower levels during the light were observed in all of the birds examined. The daily changes of melatonin persisted in LLdim, indicating circadian nature of pineal melatonin release. Moreover pineal melatonin release was inhibited by acute exposure of light during the dark. These results indicate that microdialysis is useful for studying circadian pineal melatonin rhythms of birds. 相似文献
66.
Yasuo Saegusa Yasuhiro Ozeki Shigeo Harada Shigeo Nakamura 《Macromolecular chemistry and physics.》1994,195(9):3189-3198
A novel thermally stable and semiconducting polyheterocycle, poly(1,3,4-thiadiazole amine), was synthesized from 2-(p-aminophenyl)-1,3,4-oxadiazoline-5-thione via ring-opening. The polymer is a new class of ordered alternating copoly(aniline) containing 1,3,4-thiadiazole heterocyclic units. An investigation of the reaction of 2-phenyl-1,3,4-oxadiazoline-5-thione with aniline was conducted as a model reaction for the polymerization, and poly(phosphoric acid) (PPA) and phosphorus pentoxide/methanesulfonic acid (PPMA) were found to be favorable both as condensing agent and solvent for the formation of 2-anilino-5-phenyl-1,3,4-thiadiazole as a model compound. The polymerization was carried out both by two-step procedure that included ring-opening self-polyaddition giving poly(1-benzoylthiosemicarbazide), followed by cyclodehydration to poly(1,3,4-thiadiazole amine), and by a one-step procedure including cyclodehydration in situ. The poly(1-benzoylthiosemicarbazide) which was formed in the first step in m-cresol had reduced viscosities up to 0,42 dL·g?1, and it was converted to poly(1,3,4-thiadiazole amine) by treating in PPA or PPMA. Poly(1,3,4-thiadiazole amine) having reduced viscosities up to 0,25 dL·g?1 was also synthesized by the direct one-step polymerization in PPA or PPMA. The polymer is highly thermally stable and exhibited no weight loss up to 350°C under nitrogen. Its electric conductivity was less than 10?10 S·cm?1 at ambient temperature, but markedly increased to 2,9·10?7 S·cm?1 upon doping with iodine. 相似文献
67.
Shimizu C Hasegawa T Tani Y Takahashi F Takeuchi M Watanabe T Ando M Katsumata N Fujiwara Y 《Human pathology》2004,35(12):201-1542
Insulin-like growth factor-1 receptor (IGF-1R) has been implicated in regulation in tumor growth. The results of previous studies performed by radioimmunoassay are conflicting, and the prognostic significance of IGF-1R expression in primary breast cancer is still controversial. IGF-1R expression was evaluated in formalin-fixed, paraffin-embedded tissue of 210 primary breast cancer patients by using anti-IGF-1R antibody. The clinicopathologic variables and 5-year disease-free survival were studied, and their correlations between IGF-1R expressions were investigated. IGF-1R overexpression was observed in 43.8% of tumors. IGF-1R overexpression had no correlation with prognosis or with other clinicopathologic parameters, such as age, tumor size, nodal status, histologic grade, hormone receptor status, and human epidermal growth factor 2 status. Though its prognostic value in breast cancer is limited, immunohistochemical evaluation of IGF-1R by using this monoclonal antibody may be useful in translational research using archived material. 相似文献
68.
Two closely related ubiquitin C-terminal hydrolase isozymes function as reciprocal modulators of germ cell apoptosis in cryptorchid testis
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Kwon J Wang YL Setsuie R Sekiguchi S Sato Y Sakurai M Noda M Aoki S Yoshikawa Y Wada K 《The American journal of pathology》2004,165(4):1367-1374
The experimentally induced cryptorchid mouse model is useful for elucidating the in vivo molecular mechanism of germ cell apoptosis. Apoptosis, in general, is thought to be partly regulated by the ubiquitin-proteasome system. Here, we analyzed the function of two closely related members of the ubiquitin C-terminal hydrolase (UCH) family in testicular germ cell apoptosis experimentally induced by cryptorchidism. The two enzymes, UCH-L1 and UCH-L3, deubiquitinate ubiquitin-protein conjugates and control the cellular balance of ubiquitin. The testes of gracile axonal dystrophy (gad) mice, which lack UCH-L1, were resistant to cryptorchid stress-related injury and had reduced ubiquitin levels. The level of both anti-apoptotic (Bcl-2 family and XIAP) and prosurvival (pCREB and BDNF) proteins was significantly higher in gad mice after cryptorchid stress. In contrast, Uchl3 knockout mice showed profound testicular atrophy and apoptotic germ cell loss after cryptorchid injury. Ubiquitin level was not significantly different between wild-type and Uchl3 knockout mice, whereas the levels of Nedd8 and the apoptotic proteins p53, Bax, and caspase3 were elevated in Uchl3 knockout mice. These results demonstrate that UCH-L1 and UCH-L3 function differentially to regulate the cellular levels of anti-apoptotic, prosurvival, and apoptotic proteins during testicular germ cell apoptosis. 相似文献
69.
Pathogenesis of Rinderpest Virus Infection in Rabbits II. Effect of Rinderpest Virus on the Immune Functions of Rabbits
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Kazuya Yamanouchi Akiko Fukuda Fumio Kobune Yasuhiro Yoshikawa Fumitoshi Chino 《Infection and immunity》1974,9(2):206-211
Rinderpest virus infection was shown to induce marked suppression of both humoral antibody response and cell-mediated immunity in rabbits. The virus exhibited a suppressive effect on primary antibody response as indicated by a decrease in numbers of plaque-forming cells (immunoglobulin [Ig]M) and hemagglutinating antibody titers of both IgM and IgG types to sheep red blood cells, whereas there was no detectable effect of the virus on the production of memory cells. Virus-induced suppression of cell-mediated immunity was demonstrated by a decreased rate of proliferative response of peripheral lymphocytes to phytohemagglutinin stimulus and by a depression of delayed-type skin reactions to purified protein derivative. Such suppressive effects were indicated to persist for 14 days or longer. Alteration in phagocytic activity of the reticuloendothelial system was not observed. The relevance of the virus-induced histological lesions in the lymphoid tissues to the virus-induced immunosuppression was discussed. 相似文献
70.
D2-40 antibody immunoreactivity in developing human brain, brain tumors and cultured neural cells. 总被引:1,自引:0,他引:1
Yasuhiro Nakamura Yonehiro Kanemura Tomiko Yamada Yasuo Sugita Koichi Higaki Munehiko Yamamoto Mitsuhiko Takahashi Mami Yamasaki 《Modern pathology》2006,19(7):974-985
D2-40 antibody is raised against an oncofetal antigen, the M2A antigen. It has been used as a marker for lymphatic endothelium as well as mesothelioma and cerebellar hemangioblastoma. We demonstrate here that positive D2-40 immunoreactivity was found in the developing cerebrum, particularly in the germinal matrix layer, immature ependyma, choroid plexus and meninges. In the developing cerebellum, positive D2-40 immunoreactivity was found in the external granular layer particularly of the outer portion and the Purkinje cell layer as well as meninges. Some brain tumors such as anaplastic ependymoma, some medulloblastomas, glioblastoma, pineal germinoma, craniopharyngioma, choroid plexus papilloma, choroid plexus carcinoma, and meningioma showed positive immunoreactivity with D2-40. Therefore, D2-40 antibody is considered a useful marker for research on developing brain and diagnosis of brain tumors, differentiation between choroid plexus carcinoma and metastatic carcinoma. In addition, on cultured human neural cells, D2-40 immunoreactivity was found in nestin-positive neural stem/progenitor cells and neuronal lineage cells. As D2-40 antibody recognizes cell surface antigen M2A, it might be a candidate cell surface marker for isolation of human neural stem cells/neuronal lineage cells in the fluorescence-activated cell sorting technique. 相似文献