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21.
Masanobu Hibi Satoshi Hachimura Wataru Ise Ayuko Sato Tadashi Yoshida Tsuyoshi Takayama Kastumi Sasaki Takashi Senga Shuichi Hashizume Mamoru Totsuka Shuichi Kaminogawa 《Cytotechnology》2003,43(1-3):49-55
Dendritic cells (DCs) as antigen presenting cells can stimulate naive CD4+ T cells and initiate the primary immune response which controls Th1/Th2 development. It has been suggested that DCs derived from different tissues have distinct properties. We investigated whether DCs from mesenteric lymph nodes (MLN), Peyer's patches (PP) and spleen (SPL) could induce different responses of naive CD4+ T cells to varying doses of antigen by using a co-culture system of DCs and T cells. DCs from each tissue induced IL-4 secretion from naive CD4+T cells in the presence of low dose antigenic peptide, and induced IFN-γ production at high doses of antigen. When purified CD11c+/B220? DCs were used, MLN-derived DCs induced a higher amount of IFN-γ secretion from naive CD4+ T cells, compared with SPL-derived DCs. We could not detect large differences in the expressions of costimulatory molecules on the surface of these two populations of DCs. On the other hand, we found that large amounts of IL-12 were secreted from MLN DCs in an antigen dose-dependent fashion. In conclusion, DCs from SPL, MLN and PP can induce the production of both IL-4 and IFN-γ from naive CD4+ T cells, depending on antigen dose. MLN-derived CD11c+/B220? DCs induce higher IFN-γ production from naive CD4+ T cells than SPL-derived DCs, through efficient IL-12 secretion. 相似文献
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23.
Sachiko N. Isobe Hideki Hirakawa Shusei Sato Fumi Maeda Masami Ishikawa Toshiki Mori Yuko Yamamoto Kenta Shirasawa Mitsuhiro Kimura Masanobu Fukami Fujio Hashizume Tomoko Tsuji Shigemi Sasamoto Midori Kato Keiko Nanri Hisano Tsuruoka Chiharu Minami Chika Takahashi Tsuyuko Wada Akiko Ono Kumiko Kawashima Naomi Nakazaki Yoshie Kishida Mitsuyo Kohara Shinobu Nakayama Manabu Yamada Tsunakazu Fujishiro Akiko Watanabe Satoshi Tabata 《DNA research》2013,20(1):79-92
24.
Toshiko Kido Katsuyuki Tanizawa Kenji Inagaki Tohru Yoshimura Masaaki Ishida Katsumi Hashizume 《Bioscience, biotechnology, and biochemistry》2013,77(10):2549-2554
2-Nitropropane dioxygenase, purified to homogeneity by an improved method from a yeast, Hansenula mrakii, has a molecular weight of 42,000, and consists of a single polypeptide. The enzyme contains 1 mol of FAD per mol of enzyme. The iron protein associated with previous preparations was removed by the present purification procedures. The enzyme catalyzes the oxygenative denitrification of anionic nitroalkanes much more effectively than that of the neutral ones with the optimum pH of 6.5. The Michaelis constants for the anionic substrates are as follows: 2-nitropropane, 1.61 mM; 1-nitropropane, 3.23 mM; nitroethane, 3.13 mM, and 3-nitro-2-butanol, 0.59 mM. 相似文献
25.
26.
Kazumoto Hashizume Kinji Kakiuchi Emiko Koyama Tokuji Watanabe 《Bioscience, biotechnology, and biochemistry》2013,77(4):449-459
When a solution of soybean acid-precipitated or 11S protein was frozen and stored at ?1 to ?5°C, the protein became partially insoluble after thawing. Ultracentrifugation and disc-electrophoresis of freeze-stored 11S protein solution after removing insoluble components revealed that new components which may be aggregates or associates of the 11S component were formed. When concentrated and stored at 5°C, disc-electrophoresis of 11S component showed that associates were formed. Mercaptoethanol could dissolve the insoluble protein and also convert the associates to the original 11S component. NEM–11S was not insolubilized by frozen storage at ?5°C or storage at 5°C after being concentrated. From these facts it can be concluded that denaturation of soybean protein by freezing may be caused by intermolecular reactions through S-S bonds as a result of concentration by freezing. This may suggest a mechanism of the formation of sponge-like texture in kori-tofu which is made by frozen storage of soybean curd for 15 to 20 days at ?1 to ?3°C. 相似文献
27.
Takeshi Hashizume Kaoru Kawakita Shunji Senda Tamizi Sugiyama 《Bioscience, biotechnology, and biochemistry》2013,77(12):3481-3484
Endogenous cytokinins in alfalfa were isolated, and identified by mass spectrometry, trans- Ribosylzeatin (RZ) and ribosyldihydrozeatin (DHRZ) were identified from the root, and the combined content (benzyladenine equivalent) was estimated to be approximately 0.5/μg/100 g of fresh weight, eis- and trans-KL were identified from the stems and leaves. The relative content of the m-isomer was approximately five times greater than that of the trans-isomer. 相似文献
28.
Rui Nouchi Yasuyuki Taki Hikaru Takeuchi Hiroshi Hashizume Takayuki Nozawa Toshimune Kambara Atsushi Sekiguchi Carlos Makoto Miyauchi Yuka Kotozaki Haruka Nouchi Ryuta Kawashima 《PloS one》2013,8(2)
Background
Do brain training games work? The beneficial effects of brain training games are expected to transfer to other cognitive functions. Yet in all honesty, beneficial transfer effects of the commercial brain training games in young adults have little scientific basis. Here we investigated the impact of the brain training game (Brain Age) on a wide range of cognitive functions in young adults.Methods
We conducted a double-blind (de facto masking) randomized controlled trial using a popular brain training game (Brain Age) and a popular puzzle game (Tetris). Thirty-two volunteers were recruited through an advertisement in the local newspaper and randomly assigned to either of two game groups (Brain Age, Tetris). Participants in both the Brain Age and the Tetris groups played their game for about 15 minutes per day, at least 5 days per week, for 4 weeks. Measures of the cognitive functions were conducted before and after training. Measures of the cognitive functions fell into eight categories (fluid intelligence, executive function, working memory, short-term memory, attention, processing speed, visual ability, and reading ability).Results and Discussion
Our results showed that commercial brain training game improves executive functions, working memory, and processing speed in young adults. Moreover, the popular puzzle game can engender improvement attention and visuo-spatial ability compared to playing the brain training game. The present study showed the scientific evidence which the brain training game had the beneficial effects on cognitive functions (executive functions, working memory and processing speed) in the healthy young adults.Conclusions
Our results do not indicate that everyone should play brain training games. However, the commercial brain training game might be a simple and convenient means to improve some cognitive functions. We believe that our findings are highly relevant to applications in educational and clinical fields.Trial Registration
UMIN Clinical Trial Registry 000005618. 相似文献29.
Satoshi Yamamoto Kenji Minami Keiichi Fukaya Kohji Takahashi Hideki Sawada Hiroaki Murakami Satsuki Tsuji Hiroki Hashizume Shou Kubonaga Tomoya Horiuchi Masamichi Hongo Jo Nishida Yuta Okugawa Ayaka Fujiwara Miho Fukuda Shunsuke Hidaka Keita W. Suzuki Masaki Miya Hitoshi Araki Hiroki Yamanaka Atsushi Maruyama Kazushi Miyashita Reiji Masuda Toshifumi Minamoto Michio Kondoh 《PloS one》2016,11(3)
Recent studies in streams and ponds have demonstrated that the distribution and biomass of aquatic organisms can be estimated by detection and quantification of environmental DNA (eDNA). In more open systems such as seas, it is not evident whether eDNA can represent the distribution and biomass of aquatic organisms because various environmental factors (e.g., water flow) are expected to affect eDNA distribution and concentration. To test the relationships between the distribution of fish and eDNA, we conducted a grid survey in Maizuru Bay, Sea of Japan, and sampled surface and bottom waters while monitoring biomass of the Japanese jack mackerel (Trachurus japonicus) using echo sounder technology. A linear model showed a high R2 value (0.665) without outlier data points, and the association between estimated eDNA concentrations from the surface water samples and echo intensity was significantly positive, suggesting that the estimated spatial variation in eDNA concentration can reflect the local biomass of the jack mackerel. We also found that a best-fit model included echo intensity obtained within 10–150 m from water sampling sites, indicating that the estimated eDNA concentration most likely reflects fish biomass within 150 m in the bay. Although eDNA from a wholesale fish market partially affected eDNA concentration, we conclude that eDNA generally provides a ‘snapshot’ of fish distribution and biomass in a large area. Further studies in which dynamics of eDNA under field conditions (e.g., patterns of release, degradation, and diffusion of eDNA) are taken into account will provide a better estimate of fish distribution and biomass based on eDNA. 相似文献
30.
Masatoshi Teraguchi Noriko Yoshimura Hiroshi Hashizume Shigeyuki Muraki Hiroshi Yamada Hiroyuki Oka Akihito Minamide Yuyu Ishimoto Keiji Nagata Ryohei Kagotani Sakae Tanaka Hiroshi Kawaguchi Kozo Nakamura Toru Akune Munehito Yoshida 《PloS one》2016,11(2)