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111.
Mitani Y Sato K Muramoto Y Karakawa T Kitamado M Iwanaga T Nabeshima T Maruyama K Nakagawa K Ishida K Sasamoto K 《Biochemical and biophysical research communications》2008,372(1):19-23
Pirfenidone (PFD) is focused on a new anti-fibrotic drug, which can minimize lung fibrosis etc. We evaluated the superoxide () scavenging activities of PFD and the PFD-iron complex by electron spin resonance (ESR) spectroscopy, luminol-dependent chemiluminescence assay, and cytochrome c reduction assay. Firstly, we confirmed that the PFD-iron complex was formed by mixing iron chloride with threefold molar PFD, and the complex was stable in distillated water and ethanol. Secondary, the PFD-iron complex reduced the amount of produced by xanthine oxidase/hypoxanthine without inhibiting the enzyme activity. Thirdly, it also reduced the amount of released from phorbor ester-stimulated human neutrophils. PFD alone showed few such effects. These results suggest the possibility that the scavenging effect of the PFD-iron complex contributes to the anti-fibrotic action of PFD used for treating idiopathic pulmonary fibrosis. 相似文献
112.
Karakawa T Sato K Muramoto Y Mitani Y Kitamado M Iwanaga T Nabeshima T Maruyama K Nakagawa K Ishida K Sasamoto K 《Biochemical and biophysical research communications》2008,370(1):93-97
Electron spin resonance using spin-trapping is a useful technique for detecting direct reactive oxygen species, such as superoxide (). However, the widely used spin trap 2,2-dimethyl-3,4-dihydro-2H-pyrrole N-oxide (DMPO) has several fundamental limitations in terms of half-life and stability. Recently, the new spin trap 2-diphenylphosphinoyl-2-methyl-3,4-dihydro-2H-pyrrole N-oxide (DPhPMPO) was developed by us. We evaluated the biological applicability of DPhPMPO to analyze in both cell-free and cellular systems. DPhPMPO had a larger rate constant for and formed more stable spin adducts for than DMPO in the xanthine/xanthine oxidase (X/XO) system. In the phorbol myristate acetate-activated neutrophil system, the detection potential of DPhPMPO for was significantly higher than that of DMPO (kDMPO = 13.95 M−1 s−1, kDPhPMPO = 42.4 M−1 s−1). These results indicated that DPhPMPO is a potentially good candidate for trapping in a biological system. 相似文献
113.
International Journal of Primatology - 相似文献
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116.
Qualitative differences in chromatins of adult tissues demonstrated by action of DNase 总被引:1,自引:0,他引:1
H Namiki 《Biochemical and biophysical research communications》1973,50(3):662-669
Treatment of chromatin from rat or mouse tissues with DNase rendered it tissue-specific in subsequent hybridization with H3-labeled RNA's. It hybridized least with RNA from the same organ and most efficiently with RNA's from completely different organs. DNase-residual DNA's of forebrain were sufficiently specific to distinguish in this way between RNA's from different parts of the brain. 相似文献
117.
Naoki Tokuhara Kana Namiki Mai Uesugi Chihiro Miyamoto Makoto Ohgoh Katsutoshi Ido Takashi Yoshinaga Toshihiko Yamauchi Junro Kuromitsu Sadao Kimura Norimasa Miyamoto Yoshitoshi Kasuya 《The Journal of biological chemistry》2010,285(43):33294-33306
One of the family of voltage-gated calcium channels (VGCC), the N-type Ca2+ channel, is located predominantly in neurons and is associated with a variety of neuronal responses, including neurodegeneration. A precise mechanism for how the N-type Ca2+ channel plays a role in neurodegenerative disease, however, is unknown. In this study, we immunized N-type Ca2+ channel α1B-deficient (α1B−/−) mice and their wild type (WT) littermates with myelin oligodendrocyte glycoprotein 35–55 and analyzed the progression of experimental autoimmune encephalomyelitis (EAE). The neurological symptoms of EAE in the α1B−/− mice were less severe than in the WT mice. In conjunction with these results, sections of the spinal cord (SC) from α1B−/− mice revealed a reduction in both leukocytic infiltration and demyelination compared with WT mice. No differences were observed in the delayed-type hypersensitivity response, spleen cell proliferation, or cytokine production from splenocytes between the two genotypes. On the other hand, Western blot array analysis and RT-PCR revealed that a typical increase in the expression of MCP-1 in the SC showed a good correlation with the infiltration of leukocytes into the SC. Likewise, immunohistochemical analysis showed that the predominant source of MCP-1 was activated microglia. The cytokine-induced production of MCP-1 in primary cultured microglia from WT mice was significantly higher than that from α1B−/− mice and was significantly inhibited by a selective N-type Ca2+ channel antagonist, ω-conotoxin GVIA or a withdrawal of extracellular Ca2+. These results suggest that the N-type Ca2+ channel is involved in the pathogenesis of EAE at least in part by regulating MCP-1 production by microglia. 相似文献
118.
Takachika Hiroi Kazuo Fukushima Ikuo Kantake Yuji Namiki Tadashi Ikeda 《FEMS microbiology letters》1992,96(2-3):193-198
Adherence of 3H-labelled cells of Streptococcus gordonii and Streptococcus milleri to artificial pellicles prepared from saliva supplemented with glucosyltransferases from mutants streptococci was examined using a new assay for sucrose-dependent cell-to-pellicle attachment. Results indicate that S. gordonii, but not S. milleri, could attach tightly to hydroxylapatite surfaces through de novo glucan synthesis by mutants streptococcal glucosyltransferases present in the experimental salivary pellicles. 相似文献
119.
Ryuichi Sekioka Eriko Honjo Shugo Honda Hideyoshi Fuji Hiroki Akashiba Yasuyuki Mitani Shingo Yamasaki 《Bioorganic & medicinal chemistry》2018,26(2):435-442
Gamma-secretase modulators (GSMs) selectively inhibit the production of amyloid-β 42 (Aβ42) and may therefore be useful in the management of Alzheimer’s disease. Most heterocyclic GSMs that are not derived from nonsteroidal anti-inflammatory drugs contain an arylimidazole moiety that potentially inhibits cytochrome P450 (CYP) activity. Here, we discovered imidazopyridine derivatives that represent a new class of scaffold for GSMs, which do not have a strongly basic end group such as arylimidazole. High-throughput screening identified 2-methyl-8-[(2-methylbenzyl)oxy]-3-(pyridin-4-yl)imidazo[1,2-a]pyridine (3a), which inhibited the cellular production of Aβ42 (IC50?=?7.1?µM) without changing total production of Aβ. Structural optimization of this series of compounds identified 5-[8-(benzyloxy)-2-methylimidazo[1,2-a]pyridin-3-yl]-2-ethylisoindolin-1-one (3m) as a potent inhibitor of Aβ42 (IC50?=?0.39?µM) but not CYP3A4. Further, 3m demonstrated a sustained pharmacokinetic profile in mice and sufficiently penetrated the brain. 相似文献
120.
Taisuke Togawa Tohru Adachi Daijiro Harada Tasuku Mitani Daisuke Tanaka Kimitsune Ishizaki Takayuki Kohchi Katsuyuki T. Yamato 《Journal of plant research》2018,131(6):1047-1054
The liverwort Marchantia polymorpha has become one of the model organisms, since it has less genetic redundancy, sexual and asexual modes of reproduction and a range of genomic and molecular genetic resources. Cryopreservation of fertile spermatozoa eliminates time, space and labor for growing and maintaining male plants in reproductive phase, and also provides an optional way to backup lines. Here we report a protocol to cryopreserve spermatozoa of M. polymorpha in liquid nitrogen. A cryoprotective solution containing sucrose, glycerol and egg yolk and controlled cooling and warming processes led to successful recovery of motile M. polymorpha spermatozoa after the cryogenic process. The survival rate and average motility of spermatozoa after cryopreservation were maintained at 71 and 54% of those before cryopreservation, respectively. Cryopreserved spermatozoa were capable of fertilization to form normal spores. The technique presented here confers more versatility to experiments using M. polymorpha and could be applied to preservation of plant spermatozoa in general. 相似文献