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Ogiso Manabu; Ohta Masako; Okinaga Tatsuyuki; Hoshi Motonori; Komoto Michiji; Asano Kazunobu 《Glycobiology》1994,4(3):375-382
Vertebrate lens tissues contain several species of acidic andneutral glycosphingolipids in relatively high amounts. However,the epithelia with capsule from dog and rhesus monkey lenseshad a simpler composition and lower content of glycosphingolipidsthan whole lenses. Gangliosides and neutral glycosphingolipidsin monolayer cultures of lens epithelial cells were also differentfrom those in whole lenses. Although -galactosyl (Gal1-3Ga1-R)or Lewisx (Galß1-4[Fuc1-3]GlcNAc-R) epitopes werefound in glycosphingolipids from whole lenses, they were notdetected in those from monolayer cultures of dog and rhesusmonkey lens cells. In addition, significant changes in ganglio-seriesgangliosides were induced in monolayer cultures of both cells,where GM3 and GD3 were predominant. Immunofluorescence studyrevealed a characteristic distribution of cell surface gangliosidesin confluent monolayers. These findings suggest that glycosphingolipidsynthesis in lens epithelia is intrinsically different fromthat in cortical and nuclear fibres, and that the expressionof Lewisx and -galactosyl epitopes in glycosphingolipids appearsto be associated with the differentiation of epithelial cellsto fibres. gangliosides glycosphingolipids lens epithelial cells Lewisx rhesus monkey. 相似文献
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Effect of Intracellular Glutathione Level on the Production of 6-Methoxymellein in Cultured Carrot (Daucus carota) Cells 总被引:4,自引:1,他引:3 下载免费PDF全文
To produce phytoalexin, 6-methoxymellein (6-MM) was induced in suspension cultures of carrot (Daucus carota) by buthionine sulfoximine (BSO) and CuCl2. Addition of BSO (a specific inhibitor of glutathione [GSH] synthesis) to the cultures lowered the cellular GSH levels. This depletion of GSH was BSO-concentration dependent, and the extent of 6-MM accumulation was dependent on the GSH depletion. The accumulation of 6-MM induced by BSO was suppressed by exogenous GSH. Exogenous H2O2 stimulated the production of 6-MM when added 1 d after BSO treatment, whereas H2O2 added at time zero or on the 4th d of BSO treatment did not. Moreover, a synergistic effect of simultaneous addition of BSO and CuCl2 was observed. These results suggest that active oxygen species may be involved in the triggering of 6-MM synthesis. 相似文献
75.
The patterns of destruction of several kinds of bacterial cells suspended in solutions by microwave irradiation were studied. The survival curves of Escherichia coli and Staphylococcus aureus were similar and approximated a set of three linear phases. The curves of Pseudomonas fluorescens and Bacillus cereus spores shifted to the shorter and longer irradiation periods, respectively. The rate constant and initial time of destruction for each linear phase of the survival curve were compared among these organisms. When irradiated E. coli cells were incubated in an agar with a high salt level, fewer cells were recovered. The curve of E. coli cells in the logarithmic phase of growth shifted to shorter exposure periods. There were no significant differences in the survival curves of E. coli cells grown at temperatures of 22–36°C, whereas the curve of cells grown at 44°C shifted to longer periods. 相似文献
76.
Nobuyuki Sugioka Hikaru Odani Toshio Ohta Hideki Kishimoto Tadaki Yasumura Kanji Takada 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1994,654(2)
Mycophenolate mofetil, a new immunosuppressant, is a morpholinoethyl ester of mycophenolic acid. A new selective, sensitive and simple high-performance liquid chromatographic method was developed for the determination of mycophenolic acid and mycophenolate mofetil in biological samples. The preparation of samples was based on liquid—liquid extraction. The compounds were separated on a CN column using acetonitrile—0.01 M phosphate buffer (1:4, v/v) as the mobile phase. UV detection was used at wavelengths 215 and 304 nm. The detection limit was 5 ng per injection volume. This method enabled pharmacokinetic and pharmacodynamic studies in humans and rats. 相似文献
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K. Ogawa-Goto Y. Ohta K. Kubota N. Funamoto T. Abe T. Taki K. Nagashima† 《Journal of neurochemistry》1993,61(4):1398-1403
Abstract: Compositions of neutral and sulfated glucuronyl glycosphingolipids purified from human motor and sensory nerves and myelins were studied. Higher neutral glycosphingolipids (fraction B), which were separated from GazlCer (fraction A), were analyzed by TLC and TLC-immunostaining. Both nerve myelins contained paragloboside (nLc4 Cer) and nLc6 Cer dominantly as major higher glycosphingolipids and very little globoside (Gb4 Cer), whereas both nerves contained Gb4 Cer and nLc4 Cer. Besides these major glycosphingolipids, a neutral glycolipid containing asialoGMI (Gg4 Cer) epitope and other minor components such as ceramide trihexoside and ceramide dihexoside were detected in both nerves and their myelins. Furthermore, sulfated glucuronyl nLc4 Cer and n Lc6 Cer, which were monoclonal antibody HNK-1 reactive glycolipids, were detected in both nerves and myelins. 相似文献
79.
Group I introns in the liverwort mitochondrial genome: the gene coding for subunit 1 of cytochrome oxidase shares five intron positions with its fungal counterparts. 总被引:3,自引:0,他引:3 下载免费PDF全文
E Ohta K Oda K Yamato Y Nakamura M Takemura N Nozato K Akashi K Ohyama F Michel 《Nucleic acids research》1993,21(5):1297-1305
The complete nucleotide sequence of the mitochondrial DNA (mtDNA) from a liverwort, Marchantia polymorpha, contains thirty-two introns. Twenty-five of these introns possess the characteristic secondary structures and consensus sequences of group II introns. The remaining seven are group I introns, six of which happen to interrupt the gene coding for subunit 1 of cytochrome oxidase (cox1). Interestingly, the insertion sites of one group II and four group I introns in the cox1 gene coincide with those of the respective fungal mitochondrial interns. Moreover, comparison of the four group I introns with their fungal counterparts shows that group I introns inserted at identical genomic sites in different organisms are indeed related to one another, in terms of the peptide sequences generated from the complete or fragmental ORFs encoded by these introns. At the same time, the liverwort introns turned out to be more divergent from their fungal cognates than the latter are from one another. We therefore conclude that vertical transmission from a common ancestor organism is the simplest explanation for the presence of cognate introns in liverwort and fungal mitochondrial genomes. 相似文献
80.