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991.
Thymosin α1 restores NK-cell activity and prevents tumor progression in mice immunosuppressed by cytostatics or X-rays 总被引:1,自引:0,他引:1
Yukio Umeda Atsuko Sakamoto Junko Nakamura Hideo Ishitsuka Yasuo Yagi 《Cancer immunology, immunotherapy : CII》1983,15(2):78-83
The effect of thymosin against tumor progression was examined in mice immunosuppressed by cytostatics or X-ray irradiation. When pretreated with cytostatic agents, such as 5-fluorouracil (5-FU) or BCNU, or by X-ray, and then inoculated with P388 or L1210 leukemias, mice died rapidly within a few days. In these systems, thymosin alpha 1 given concomitantly with the cytostatic agents or after X-irradiation prevented rapid death and extended survival, although the mice eventually died with leukemia like normal mice inoculated with cells of the same tumor. Rapid death in the 5-FU-treated mice was also prevented by adoptive transfer of spleen cells from the donor mice if these had been treated with 5-FU plus thymosin alpha 1, but not if they had received 5-FU alone. However, the restorative activity of the donor spleen cells was abrogated by treatment with anti-asialo GM1, but not by treatment with anti-Thy 1 or anti-mouse Ig serum, suggesting that the effector cells in the spleen are NK cells. In fact, thymosin alpha 1, when given concomitantly with 5-FU or after X-irradiation, maintained the NK activity of spleen, which was damaged by treatment with 5-FU or X-irradiation alone. The present study indicates that thymosin alpha 1 exerts a preventive activity against progression of leukemias at least in part through an effect on NK cells or their progenitor cells. 相似文献
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993.
Maina Sogabe Masayuki Ohzeki Koji Fujimoto Atsuko Sehara‐Fujisawa Satoshi Nishimura 《Journal of biophotonics》2020,13(5)
Dynamic intravital imaging is essential for revealing ongoing biological phenomena within living organisms and is influenced primarily by several factors: motion artifacts, optical properties and spatial resolution. Conventional imaging quality within a volume, however, is degraded by involuntary movements and trades off between the imaged volume, imaging speed and quality. To balance such trade‐offs incurred by two‐photon excitation microscopy during intravital imaging, we developed a unique combination of interlaced scanning and a simple image restoration algorithm based on biological signal sparsity and a graph Laplacian matrix. This method increases the scanning speed by a factor of four for a field size of 212 μm × 106 μm × 130 μm, and significantly improves the quality of four‐dimensional dynamic volumetric data by preventing irregular artifacts due to the movement observed with conventional methods. Our data suggest this method is robust enough to be applied to multiple types of soft tissue. 相似文献
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Tadahito Yasuda Mayu Koiwa Atsuko Yonemura Keisuke Miyake Ryusho Kariya Sho Kubota Takako Yokomizo-Nakano Noriko Yasuda-Yoshihara Tomoyuki Uchihara Rumi Itoyama Luke Bu Lingfeng Fu Kota Arima Daisuke Izumi Shiro Iwagami Kojiro Eto Masaaki Iwatsuki Yoshifumi Baba Takatsugu Ishimoto 《Cell reports》2021,34(8):108779
998.
Atsuko Miyagi Hideyuki Takahashi Kentaro Takahara Takayuki Hirabayashi Yoshiki Nishimura Takafumi Tezuka Maki Kawai-Yamada Hirofumi Uchimiya 《Metabolomics : Official journal of the Metabolomic Society》2010,6(1):146-155
Comprehensive analysis of metabolites using capillary electrophoresis–mass spectrometry was carried out in harmful weeds belonging
to Polygonaceae. A principal component analysis revealed clear distinctions among eight Rumex species and Fallopia japonica. Hierarchical clustering data showed that respective metabolites can be grouped due to species differences. There was a positive
relationship between oxalate and citrate, oxalate and ascorbate, and oxalate and glutamine. The amount of oxalate per leaf
fresh weight was not affected by increased concentrations of exogenously supplied nutrients from Hoagland’s formulation in
one of the most destructive weeds R. obtusifolius. The oxalate accumulation in this plant is independent of external nutrient level, where nutrient-rich environments apparently
stimulate internal constituents such as amino acids and other metabolites. 相似文献
999.
S-Adenosylmethionine decarboxylase activity in leaves of Pharbitisnil increased dramatically at lights-on and then gradually decreasedin the light. The enzymatic activity fell dramatically at lights-offthen increased slightly in darkness. Photoinduction was preventedby cycloheximide and the enzymatic activity fell dramaticallyupon treatment with cycloheximide in the light.
1Present address: Sakuya Konohana Kan, Osaka City Parks Association,Tsurumi-ku, Osaka, 538 Japan 相似文献
1000.
Akira C. Saito Tomohito Higashi Yugo Fukazawa Tetsuhisa Otani Masashi Tauchi Atsuko Y. Higashi Mikio Furuse Hideki Chiba 《Molecular biology of the cell》2021,32(8):722
Tight junctions (TJs) are composed of a claudin-based anastomosing network of TJ strands at which plasma membranes of adjacent epithelial cells are closely attached to regulate the paracellular permeability. Although the TJ proteins occludin and tricellulin have been known to be incorporated in the TJ strand network, their molecular functions remain unknown. Here, we established tricellulin/occludin-double knockout (dKO) MDCK II cells using a genome editing technique and evaluated the structure and barrier function of these cells. In freeze-fracture replica electron microscopy, the TJ strands of tricellulin/occludin-dKO cells had fewer branches and were less anastomosed compared with the controls. The paracellular permeability of ions and small tracers was increased in the dKO cells. A single KO of tricellulin or occludin had limited effects on the morphology and permeability of TJs. Mathematical simulation using a simplified TJ strand network model predicted that reduced cross-links in TJ strands lead to increased permeability of ions and small macromolecules. Furthermore, overexpression of occludin increased the complexity of TJ strand network and strengthened barrier function. Taken together, our data suggest that tricellulin and occludin mediate the formation and/or stabilization of TJ-strand branching points and contribute to the maintenance of epithelial barrier integrity. 相似文献