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991.
992.
Tetsuo Mitsui Naoto Fujita Yuhki Koga Reiji Fukano Tomoo Osumi Asahito Hama Katsuyoshi Koh Harumi Kakuda Masami Inoue Takahiro Fukuda Hiromasa Yabe Junko Takita Akira Shimada Yoshiko Hashii Atsushi Sato Yoshiko Atsuta Yoshinobu Kanda Junji Suzumiya Ryoji Kobayashi 《Pediatric blood & cancer》2020,67(4)
993.
994.
Nakahara Keiichi Nakane Shunya Kitajima Mika Masuda-Narita Tomoko Matsuo Hidenori Ando Yukio 《Journal of neurology》2020,267(3):752-759
Journal of Neurology - To determine the usefulness of MRI measurements in patients with pure akinesia with gait freezing (PAGF), Richardson’s syndrome, and Parkinson’s disease for... 相似文献
995.
Masahito Sawahata Daisuke Mori Yuko Arioka Hisako Kubo Itaru Kushima Kanako Kitagawa Akira Sobue Emiko Shishido Mariko Sekiguchi Akiko Kodama Ryosuke Ikeda Branko Aleksic Hiroki Kimura Kanako Ishizuka Taku Nagai Kozo Kaibuchi Toshitaka Nabeshima Kiyofumi Yamada Norio Ozaki 《Psychiatry and clinical neurosciences》2020,74(5):318-327
996.
997.
Repair of DNA damage induced by the novel nucleoside analogue CNDAG through homologous recombination
Xiaojun Liu Yingjun Jiang Billie Nowak Satoshi Ichikawa Masaki Ohtawa Akira Matsuda William Plunkett 《Cancer chemotherapy and pharmacology》2020,85(4):661-672
We postulate that the deoxyguanosine analogue CNDAG [9-(2-C-cyano-2-deoxy-1-β-d-arabino-pentofuranosyl)guanine] likely causes a single-strand break after incorporation into DNA, similar to the action of its cytosine congener CNDAC, and that subsequent DNA replication across the unrepaired nick would generate a double-strand break. This study aimed at identifying cellular responses and repair mechanisms for CNDAG prodrugs, 2-amino-9-(2-C-cyano-2-deoxy-1-β-d-arabino-pentofuranosyl)-6-methoxy purine (6-OMe) and 9-(2-C-cyano-2-deoxy-1-β-d-arabino-pentofuranosyl)-2,6-diaminopurine (6-NH2). Each compound is a substrate for adenosine deaminase, the action of which generates CNDAG. Growth inhibition assay, clonogenic survival assay, immunoblotting, and cytogenetic analyses (chromosomal aberrations and sister chromatid exchanges) were used to investigate the impact of CNDAG on cell lines. The 6-NH2 derivative was selectively potent in T cell malignant cell lines. Both prodrugs caused increased phosphorylation of ATM and its downstream substrates Chk1, Chk2, SMC1, NBS1, and H2AX, indicating activation of ATM-dependent DNA damage response pathways. In contrast, there was no increase in phosphorylation of DNA-PKcs, which participates in repair of double-strand breaks by non-homologous end-joining. Deficiency in ATM, RAD51D, XRCC3, BRCA2, and XPF, but not DNA-PK or p53, conferred significant clonogenic sensitivity to CNDAG or the prodrugs. Moreover, hamster cells lacking XPF acquired remarkably more chromosomal aberrations after incubation for two cell cycle times with CNDAG 6-NH2, compared to the wild type. Furthermore, CNDAG 6-NH2 induced greater levels of sister chromatid exchanges in wild-type cells exposed for two cycles than those for one cycle, consistent with increased double-strand breaks after a second S phase. CNDAG-induced double-strand breaks are repaired mainly through homologous recombination. 相似文献
998.
999.
1000.
Akira Ito Yoshifumi Itoh Yo Mori Yasuyuki Sasaguri Minoru Morimatsu 《Arthritis \u0026amp; Rheumatology》1992,35(10):1197-1201
Objective. High levels of interleukin-6 (IL-6) have been found in the synovial fluid of patients with rheumatoid arthritis (RA). We undertook the present study to investigate the role of IL-6 in this disease. Methods. We examined the effects of IL-6, in comparison with IL-1, on the biosynthesis of extracellular matrix macromolecules and of matrix-degrading proteinases in rheumatoid synovial fibroblasts. Results. In rheumatoid synovial fibroblasts, IL-6 by itself enhanced the production of plasminogen activator, its inhibitor, and tissue inhibitor of metalloproteinases, whereas it did not modulate the biosynthesis of precursor of matrix metalloproteinase 1 (proMMP-1) (tissue collagenase), proMMP-3 (stromelysin), or connective tissue components. However, IL-1–induced production of proMMP-1 and proMMP-3 was preferentially augmented by IL-6. Conclusion. These results suggest that in RA, IL-6 may participate along with IL-1 in fine tuning of the catabolism of connective tissue components, by modulating the balance between connective tissue–degrading enzymes and their inhibitors. 相似文献