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71.
Developmental switch from GABA to glycine release in single central synaptic terminals 总被引:8,自引:0,他引:8
Nabekura J Katsurabayashi S Kakazu Y Shibata S Matsubara A Jinno S Mizoguchi Y Sasaki A Ishibashi H 《Nature neuroscience》2004,7(1):17-23
Early in postnatal development, inhibitory inputs to rat lateral superior olive (LSO) neurons change from releasing predominantly GABA to releasing predominantly glycine into the synapse. Here we show that spontaneous miniature inhibitory postsynaptic currents (mIPSCs) also change from GABAergic to glycinergic over the first two postnatal weeks. Many 'mixed' mIPSCs, resulting from co-release of glycine and GABA from the same vesicles, are seen during this transition. Immunohistochemistry showed that a large number of terminals contained both GABA and glycine at postnatal day 8 (P8). By P14, both the content of GABA in these mixed terminals and the contribution of GABA to the mixed mIPSCs had decreased. The content of glycine in terminals increased over the same period. Our results indicate that switching from GABAergic to glycinergic inputs to the LSO may occur at the level of a single presynaptic terminal. This demonstrates a new form of developmental plasticity at the level of a single central synapse. 相似文献
72.
Yuko Ikeda Masato Tabuchi Yasuhiro Sekiguchi Yoshikazu Miyake Shinzo Kohjiya 《Macromolecular chemistry and physics.》1994,195(11):3615-3628
A useful instrument for polymer film preparation by solution casting was employed in this study. It enabled us to control the solvent evaporation rate of the polymer solution. By using this instrument, the aggregation of hard segments in segmented poly(urethane-urea) (SPUU) was investigated. SPUU was prepared from poly(tetramethy1ene oxide), 4,4′-diphenylmethane diisocyanate and ethylenediamine. The effect of solvent evaporation rate on the microphase-separated structure of SPUU was elucidated by dynamic mechanical analysis, tensile test, differential scanning calorimetry analysis, small-angle X-ray scattering measurement, IR and IR dichroism analyses. The aggregation of hard segments in SPUU was observed to be affected considerably by the solvent evaporation rate of the cast film during the preparation. It was found that the slower the solvent evaporation rate, the higher the aggregation of hard segments to form rigid hard segment domains in SPUU. Nine months after casting, this casting effect still remained on the aggregation state of hard segments of SPUU films, although the interdomain spacing was not influenced by its rate. 相似文献
73.
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
74.
Relationship between the intestinal permeability to macromolecules and invasion of septicemia-inducing Escherichia coli in neonatal piglets. 下载免费PDF全文
The influence of age and diet on the invasion of septicemia-inducing Escherichia coli and the endocytotic activity of the small intestinal epithelium were examined in colostrum-deprived conventional and gnotobiotic piglets orally infected with E. coli 078. The piglets infected at birth and the animals fed glucose-amino acids solution and infected at 3 days after birth soon suffered from septicemia caused by the invasion of E. coli 378. The piglets fed artifical milk and infected at 3 days after birth, however, showed resistance to the invasion of E. coli in the absence of passively acquired serum gamma globulin. The endocytotic activity of the small intestinal epithelium was more intense in the former than in the latter piglets. Some of the ileal epithelial cells of the piglets infected at birth contained organisms, although these cells were morphologically intact and showed intense endocytosis. The present results suggest that the intestinal permeability to macromolecules, which depends on the endocytotic activity of the small intestinal epithelium, might predispose neonatal piglets to colisepticemia. 相似文献
75.
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
76.
77.
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
78.
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
79.
Two closely related ubiquitin C-terminal hydrolase isozymes function as reciprocal modulators of germ cell apoptosis in cryptorchid testis 下载免费PDF全文
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
80.
Pathogenesis of Rinderpest Virus Infection in Rabbits II. Effect of Rinderpest Virus on the Immune Functions of Rabbits 下载免费PDF全文
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