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101.
102.
Molecular species of cerebrosides in fruiting bodies of Lentinus edodes and their biological activity 总被引:2,自引:0,他引:2
G Kawai 《Biochimica et biophysica acta》1989,1001(2):185-190
Cerebroside fraction was obtained from fresh fruiting bodies of Lentinus edodes and separated into ten molecular species by reverse-phase high-performance liquid chromatography. The species were identified by GLC, GC-MS and NMR. Their component glycosides and sphingoids were uniformly glucose and (4E,8E)-9-methyl-4,8-sphingadienine, respectively. The component fatty acids were 2-hydroxy acids with the carbon chain length of 16, 15, 14, 18, 24, 17, 25, 26, 22 and 23 (from major to minor). The cerebrosides with the C14-18 fatty acids showed strong fruiting-inducing activity in Schizophyllum commune. Those with the C22 and C23 ones had one-eighth and one-sixteenth of the activity, respectively, and those with C24-26 had no detectable activity. 22 and 23 must be the carbon chain lengths of the component fatty acid of the sphingolipids critical for expression of biological activity. 相似文献
103.
Several attempts were made to investigate the mechanism of the asymmetrical radical formation in yttrium-90-beta-irradiated D- and L-alanines which was reported in the preceding paper (1). The experiments demonstrated that the magnitude of the asymmetry was dependent on beta-ray dose, namely the lower the dose the larger the observed difference was, and that no difference could be detected when the alanines were irradiated in aqueous state. The results in the present study seem to that different interaction between the crystal structure of the two enantiomers and polarized beta-rays may be responsible for the observed phenomenon. 相似文献
104.
J Itoh K Kawai A Serizawa K Yasumura K Ogawa R Y Osamura 《The journal of histochemistry and cytochemistry》2000,48(4):569-578
There has been considerable interest in the relationship between hormone- secreting endocrine cells and their microvessels in human pituitary gland. However, microcirculatory networks have rarely been studied in three dimensions (3D). This study was designed to visualize and to reveal the relationship between hormone-secreting endocrine cells and their microvessel environment in 3D, using rat pituitary glands under various (hyper/hypo) experimental conditions by confocal laser scanning microscopy (CLSM). Female adult Wistar rats were used after bilateral adrenalectomy or ACTH administration for 2 weeks. Clear 3D reconstructed images of ACTH cells, the microvessel network and counterstained nuclei were obtained at a maximal focus depth of 1 mm by CLSM without any background noise. In the hyperfunctional state, slender cytoplasmic processes of hypertrophic stellate ACTH cells frequently extended to the microvessels. In the hypofunctional state, ACTH cells appeared atrophic and round with scanty cytoplasm, and cytoplasmic adhesions to microvessel network patterns were inconspicuous. Therefore, 3D reconstructed imaging by CLSM is a useful technique with which to investigate the microvessel environment of hormone-secreting cells and has the potential to reveal dynamic hormone-secreting pathways. 相似文献
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106.
Rieko Oyama Fusako Kito Marimu Sakumoto Kumiko Shiozawa Shunichi Toki Akihiko Yoshida Akira Kawai Tadashi Kondo 《In vitro cellular & developmental biology. Animal》2018,54(3):257-263
Undifferentiated pleomorphic sarcoma (UPS) is an aggressive mesenchymal malignancy requiring novel therapeutic approaches to improve clinical outcome. Patient-derived cancer cell lines are an essential tool for investigating molecular mechanisms underlying cancer initiation and development; however, there is a lack of patient-derived cell lines of UPS available for research. The objective of this study was to develop a patient-derived cell model of UPS. A cell line designated NCC-UPS2-C1 was established from the primary tumor tissue of an 84-yr-old female patient with UPS. The short tandem repeat pattern of NCC-UPS2-C1 cells was identical to that of the original tumor and distinct from that of any other cell lines deposited in public cell banks. NCC-UPS2-C1 cells were maintained as a monolayer culture for over 80 passages during 30 mo and exhibited spindle-like morphology, continuous growth, and ability for spheroid formation and invasion. Proteomic profiling using mass spectrometry and functional treemap analysis revealed that the original tumor and the derived NCC-UPS2-C1 cells had similar but distinct protein expression patterns. Our results indicate that a novel UPS cell line was successfully established and could be used to study UPS development and effects of anti-cancer drugs. However, the revealed difference between proteomes of the original tumor and NCC-UPS2-C1 cells should be further investigated to determine the appropriate applications of this cell line in UPS research. 相似文献
107.
Summary Rubroskyrin, a modified bisanthraquinone pigment from an yellow rice moldPenicillium islandicum Sopp, was examined for its redox-interaction with the mitochondrial respiratory chain by using rat liver submitochondrial
particles (SMP) and was compared with luteoskyrin and rugulosin.
Rubroskyrin showed a redox interaction with the NAD-linked respiratory chain of SMP, promoting NADH oxidase in the presence
of rotenone, a specific inhibitor to coupling site I of the respiratory chain. Rubroskyrin-mediated NADH oxidase was not inhibited
by antimycin A and cyanide, inhibitors to coupling sites II and III, respectively, indicating a generation of an electron
transport shunt from a rotenone-insensitive site of NADH dehydrogenase (complex I) to dissolved oxygen. An electrontransport
shunt to cytochromec oxidase from complex I was also observed in the experiment with cytochromec and antimycin A. Rubroskyrin did not interact with succinate-linked respiratory chain.
Such enzymatic redox response which generates electron transport shunt was not detected for luteoskyrin and rugulosin in the
present study. 相似文献
108.
P.-S. Gao X.-Q. Mao M. Kawai T. Enomoto S. Sasaki O. Tanabe K. Yoshimura S. R. Shaldon Y. Dake H. Kitano P. Coull T. Shirakawa J. M. Hopkin 《Human genetics》1998,103(1):57-59
The gene encoding Clara cell-derived inflammatory molecule CC16 has been cited as a candidate gene for atopic asthma on chromosome
11q13. A genetic association study was performed with variants of the CC16 gene on chromosome 11q13 in relation to asthma
in British (n=275) and Japanese (n=300) populations. No significant association was found between asthma and CC16 genotypes, irrespective of atopic status in
these two populations. These data suggest that CC16 might not be the major locus for asthma on 11q13.
Received: 22 December 1997 / Accepted: 9 February 1998 相似文献
109.
110.