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排序方式: 共有337条查询结果,搜索用时 31 毫秒
51.
In this study, we present findings that suggest that PI3K-C2α, a member of the class II phosphoinositide 3-kinase (PI3K) subfamily, regulates the process of FcεRI-triggered degranulation. RBL-2H3 cells were transfected with shRNA targeting PI3K-C2α. The knockdown impaired the FcεRI-induced release of a lysosome enzyme, β-hexosaminidase, without affecting the intracellular Ca2+ mobilization. The release of mRFP-tagged neuropeptide-Y, a reporter for the regulated exocytosis, was also decreased in the PI3K-C2α-deficient cells. The release was increased significantly by the expression of the siRNA-resistant version of PI3K-C2α. In wild-type cells, FcεRI stimulation induced the formation of large vesicles, which were associated with CD63, a marker protein of secretory granules. On the vesicles, the existence of PI3K-C2α and PtdIns(3,4)P2 was observed. These results indicated that PI3K-C2α and its product PtdIns(3,4)P2 may play roles in the secretory process. 相似文献
52.
Takushi Nagata Kiyomi Imagawa Tohru Yamada
Teruaki Mukaiyama
《Inorganica chimica acta》1994,220(1-2):283-287A novel manganese(III) complex having an optically active N, N′-ethylenebis-β-ketoimine ligand was prepared and characterized crystallographically. The manganese(III) complexes behave as effective catalysts in enantioselective epoxidation of unfunctionalized olefins by combined use of molecular oxygen, an oxidant, and pivalaldehyde, a reductant. Dihydronaphthalene derivatives were converted into the corresponding optically active epoxides with good to high enantioselectivities. 相似文献
53.
Green-leaved and red-leaved Perilla plants (short-day plants)cultured aseptically on diluted modified White's medium or onfull strength White's medium (W) containing reduced concentrationsof nitrogen sources, initiated flower buds under continuouslight (2,0002,200 lux fluorescent lamps) at 2426?C.The addition of sucrose to the medium promoted flower formation;the optimum concentration was 2% in 1/10?W medium. The plantscultured on unfertilized vermiculite also developed flower budsreadily, unlike those on fertilized vermiculite. High-intensity light (8,000 lux fluorescent lamps) given duringthe first 30 days of culture promoted flowering. This effectwas also produced to a lesser degree by the addition of sucroseto the medium, instead. On the other hand, high-intensity lightgiven during the second 30 days or throughout the culture periodinhibited flowering, irrespective of the presence of sucrosein the medium. (Received February 4, 1982; Accepted June 14, 1982) 相似文献
54.
Thalita Macedo Araújo Magalhães Teixeira Souza Raphael Hermano Santos Diniz Celina Kiyomi Yamakawa Lauren Bergmann Soares Jaciane Lutz Lenczak Juliana Velasco de Castro Oliveira Gustavo Henrique Goldman Edilene Alves Barbosa Anna Clara Silva Campos Ieso Miranda Castro Rogelio Lopes Brandão 《Antonie van Leeuwenhoek》2018,111(10):1749-1766
This work was performed to verify the potential of yeast strains isolated from cachaça distilleries for two specific biotechnological applications: beer and bioethanol production. In the beer production, the strains were tested for characteristics required in brewery practices, such as: capacity to ferment maltose and maltotriose, ability to grow at lowest temperatures, low H2S production, and flocculation profile. Among the strains tested, two of them showed appropriate characteristics to produce two different beer styles: lager and ale. Moreover, both strains were tested for cachaça production and the results confirmed the capacity of these strains to improve the quality of cachaça. In the bioethanol production, the fermentation process was performed similarly to that used by bioethanol industries: recycling of yeast biomass in the fermentative process with sulfuric acid washings (pH 2.0). The production of ethanol, glycerol, organic acids, dry cell weight, carbohydrate consumption, and cellular viability were analyzed. One strain presented fermentative parameters similar to PE2, industrial/commercial strain, with equivalent ethanol yields and cellular viability during all fermentative cycles. This work demonstrates that cachaça distilleries seem to be an interesting environment to select new yeast strains to be used in biotechnology applications as beer and bioethanol production. 相似文献
55.
Masayuki Shibata Motohiko Hirotsuka Yukiko Mizutani Haruya Takahashi Teruo Kawada Kentaro Matsumiya 《Bioscience, biotechnology, and biochemistry》2018,82(3):507-514
Soybeans (Glycine max (L,) Merr,) contain γ-glutamyl peptides and oligosaccharides, and these components play an important role in imparting the “kokumi” taste to foods. To gain insight into the genetic diversities and molecular mechanisms of accumulation of γ-glutamyl peptides and oligosaccharides in soybean, we measured the contents of these components using the Japan and World mini core collections. Similar to other previously reported traits, wide variations were detected among the accessions in the core collections with respect to the content of γ-glutamyl peptides and oligosaccharides. We found a positive relationship between the content of γ-glutamyl tyrosine and γ-glutamyl phenylalanine and between the content of raffinose and stachyose. Furthermore, there were unique accessions that included high levels of γ-glutamyl peptides and oligosaccharides. These accessions may be helpful in understanding the accumulation mechanism of γ-glutamyl peptides and oligosaccharides and to increase the “kokumi” taste components in soybean by performing a genetic analysis. 相似文献
56.
Tadayoshi Taniyama Setsuo Takai Emi Miyazaki Ryutaro Fukumura Junko Sato Yoshiro Kobayashi Tadashi Hirakawa Kevin W. Moore Kiyomi Yamada 《Human genetics》1995,95(1):99-101
The human interleukin-10 receptor (IL-10R) gene has previously been mapped to chromosome 11. Here, we have determined the precise location of the human IL-10R gene by the fluorescence in situ hybridization method, and have found that the IL-10R gene maps to chromosome 11q23.3. 相似文献
57.
Kazuyuki Hiramoto Akiko Nasuhara Kae Michikoshi Tetsuta Kato Kiyomi Kikugawa 《Mutation Research - Genetic Toxicology and Environmental Mutagenesis》1997,395(1):4636
Aqueous solution of glucose and glycine was heated under reflux for 4 h and extracted with ethyl acetate. Reversed phase HPLC of the extract revealed a new DNA strand-breaking substance, which was purified by repeated HPLC and identified as 2,3-dihydro-3,5-dihydroxy-6-methyl-4H-pyran-4-one (DDMP). DDMP induced DNA strand breaking in a dose- and time-dependent manner. It was active to break DNA strands at pH 7.4 and 9.4. Its pyranone skeleton was destroyed at the pH values. DNA strand breaking by DDMP was inhibited by superoxide dismutase, catalase, scavengers for hydroxyl radical, spin trapping agents and metal chelators, and the breaking was enhanced by Fe(III) ion. A mixture of DDMP and a spin trap DMPO gave electron spin resonance signals of a spin adduct DMPO-OH, indicating generation of hydroxyl radical. DDMP was found to be mutagenic to Salmonella typhimurium TA100 without metabolic activation. These results show DDMP generated active oxygen species to cause DNA strand breaking and mutagenesis. 相似文献
58.
Using an isogenic line of rice having lazy gene (la), we studied the correlation between the agravitropic response at the young seedling stage and the lazy habit (prostrate
growth of tillers) at the more advanced stage of growth. In this study, it was found that both agravitropism and lazy habit
were controlled by the single recessivela gene. That is, F2 segregants of Kamenoo×lazy-Kamenoo, which had an agravitropic response at their young seedling stage, showed a lazy habit
of growth in the more advanced stage of vegetative growth. On the other hand, seedlings that showed normal gravitropic curvature
at their early stage of growth had an upright growth in the mature stage. 相似文献
59.
Tetsuji Nagano Kazuhisa Ichimura Norihiko Haji Kazuya Nagao Kazuhiko Someya Tomoko Kiyohara Kiyomi Suzuki Misao Tsubokura Koichi Otsuki 《Microbiology and immunology》1997,41(3):175-183
The biological properties of non-melibiose-fermenting (NMF) strains of Yersinia pseudotuberculosis 03 were investigated. These strains were clearly distinguished from representative melibiose-fermenting (MF) strains of Y. pseudotuberculosis 03 by their pathogenicity in mice, sensitivity to some phages, production of catalase, restriction endonuclease analysis of virulence plasmid DNA with BamHI, detection of specific yersinia outer-membrane proteins with SDS-PAGE, antigenicity of the outer-membrane proteins and neutrophil resistance to phagocytosis. The pathogenicity of NMF strains was clearly less than that of MF strains. In addition, the resistance of NMF strains to phagocytosis and catalase activity was evidently weaker than that of MF strains. These results suggested that the difference of pathogenicity was due to the ability of catalase production. Although the relationship between the above characteristics and melibiose-fermentation was not analysed, the pathogenicity of Y. pseudotuberculosis 03 strains can probably be predicted by testing melibiose-fermentation and catalase production. 相似文献
60.
Contrasting traits,contrasting environments,and considerations on population dynamics under a changing climate: an ecophysiological field study of two co‐dominant tree species 下载免费PDF全文
Edgard A. Bontempo e Silva Kiyomi Ono Akihiro Sumida Shigeru Uemura Toshihiko Hara 《Plant Species Biology》2016,31(1):38-49
The increase in light availability resulting from canopy changes or opening is not always beneficial and can inhibit photosynthesis of tree seedlings already under other environmental stress. Tree seedlings' responses to compounded abiotic stress depend on their life‐history traits, and understanding the variations of such responses is important for understanding population dynamics under a changing climate. In this study we investigate how the photosynthesis of juveniles of two canopy tree species with different life‐history traits, Abies sachalinensis and Betula ermanii, differs in two contrasting sites at a sub‐boreal forest in northern Japan—one under a deciduous canopy (Closed site) and the other at a wide canopy opening (Open site). Seedlings at the Open site had low Fv/Fm (quantum yield of photosystem II) for a longer period than those at the Closed site. Abies sachalinensis at the Closed site showed lower Fv/Fm in spring than those at the Open site, but recovered after the canopy's new leaves flushed, indicating its acclimation to the shaded condition. Mean Pmax (light‐saturated photosynthetic rate at ambient CO2 levels) of A. sachalinensis seedlings was affected by site and air temperature, while B. ermanii seedlings were also affected by precipitation. Only B. ermanii's seedlings presented growth in the period studied, in spite of observed mid‐day drops to Fv/Fm attributed to water‐deficit‐related photoprotection. Results suggest that the climate change predicted for the Hokkaido area may increase the competitive advantage of broad‐leaved deciduous species, such as B. ermanii, in relation to evergreen conifers like A. sachalinensis. 相似文献