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991.
Moeko Noguchi-Shinohara Sohshi Yuki Chiaki Dohmoto Yoshihisa Ikeda Miharu Samuraki Kazuo Iwasa Masami Yokogawa Kimiko Asai Kiyonobu Komai Hiroyuki Nakamura Masahito Yamada 《PloS one》2014,9(5)
Our objective was to determine whether the consumption of green tea, coffee, or black tea influences the incidence of dementia and mild cognitive impairment (MCI) in older people. We conducted a population-based prospective study with Japanese residents aged >60 years from Nakajima, Japan (the Nakajima Project). Participants received an evaluation of cognitive function and blood tests. The consumption of green tea, coffee, and black tea was also evaluated at baseline. Of 723 participants with normal cognitive function at a baseline survey (2007–2008), 490 completed the follow up survey in 2011–2013. The incidence of dementia during the follow-up period (mean ± SD: 4.9±0.9 years) was 5.3%, and that of MCI was 13.1%. The multiple-adjusted odds ratio for the incidence of overall cognitive decline (dementia or MCI) was 0.32 (95% CI: 0.16–0.64) among individuals who consumed green tea every day and 0.47 (95% CI: 0.25–0.86) among those who consumed green tea 1–6 days per week compared with individuals who did not consume green tea at all. The multiple-adjusted odds ratio for the incidence of dementia was 0.26 (95% CI: 0.06–1.06) among individuals who consumed green tea every day compared with those who did not consume green tea at all. No association was found between coffee or black tea consumption and the incidence of dementia or MCI. Our results indicate that green tea consumption is significantly associated with reduced risk of cognitive decline, even after adjustment for possible confounding factors. 相似文献
992.
Kimiko Okabe 《Experimental & applied acarology》1999,23(8):653-658
A bioassay was developed to quantify germination rates of Hypocrea nigricans spores passing through the alimentary canals of the three acarid mite species Tyrophagus putrescentiae, Histiogaster sp. and Schwiebea sp. These mites are suspected of causing damage to mushroom production in Japan. All three species feed on the fungus and excrete fungal spores and fungal particles. Fecal material of the mites was plated on malt agar plates supplemented with 1% CuSO4 to assess spore germination. Germination rates, and hence the possibility for the mites to disseminate spores of H. nigricans, was so high that these mites may indeed be important vectors of weed fungal spores in indoor mushroom production units. 相似文献
993.
Gene delivery systems using the Sendai virus. 总被引:1,自引:0,他引:1
M Nakanishi H Mizuguchi K Ashihara T Senda A Eguchi A Watabe T Nakanishi M Kondo T Nakagawa A Masago J Okabe S Ueda T Mayumi T Hayakawa 《Molecular membrane biology》1999,16(1):123-127
Fusogenic liposome (FL) is a delivery system that can transfer encapsulated materials into living cells directly through membrane fusion. FL is a promising approach for gene therapy because it can deliver various genetic materials much more efficiently than other non-viral vectors without damaging the cell. FL-mediated gene transfer consists of two independent membrane fusion phenomena; generation of a FL by fusing a Sendai virus (SV) particle with a simple liposome encapsulating DNA, and successive fusion of the FL with cell membrane. The former requires viral F protein but no other special molecule on the liposomal membrane, whereas the latter may require the receptor (sialic acid) and unidentified assistant molecule(s) on the cell membrane. Further analysis suggests that these assistant molecule(s), not the receptor, may control the fusion and govern the cell specificity of FL-mediated delivery. This review has described a detailed analysis of these fusion phenomena and discussed possible applications of FL-mediated gene delivery to human gene therapy. 相似文献
994.
Motohiro Hasegawa Kimiko Okabe Kenji Fukuyama Shun’ichi Makino Isamu Okochi Hiroshi Tanaka Hideaki Goto Takeo Mizoguchi Tadashi Sakata 《Experimental & applied acarology》2013,59(4):391-408
The community structures of Mesostigmata, Prostigmata, and Oribatida in the soil of broad-leaved regeneration forests and conifer plantations of various ages were assessed alongside soil and plant environmental variables using three response metrics (density, species richness, and species–abundance distribution). The density and species richness of mites recovered swiftly after clear-cutting or replanting. Oribatid mites dominated the soil mite communities in terms of densities and species richness for both forest types. Soil mite communities in broad-leaved forests was related to forest age, the crown tree communities index, and forest-floor litter weight. In contrast, soil mite communities in the conifer plantation sites were related to various indices of understory plants. The development of the understory plants was synchronized with the silvicultural schedules, including a closed canopy and thinning. Such a conifer plantation management may affect indirectly the community of mites. 相似文献
995.
Mohammed Abdel-Wahab Yoshiyuki Ota Hironori Juichi Ryota Okabe Moustafa Sarhan 《Bioscience, biotechnology, and biochemistry》2017,81(11):2086-2089
A novel anti-mollusk conopeptide pn4c was isolated from the Conus pennaceus venom by repeated HPLC fractionation based on the activity against freshwater snails. The primary structure of pn4c was determined by the mass spectrometric de novo sequencing analysis. In addition, pn3a was isolated from the same fraction containing pn4c, as a peptide with unknown functions. 相似文献
996.
997.
Recombinant Mycobacterium sp. strain MR65 harboring dszABCD genes was used to desulfurize alkyl dibenzothiophenes (Cx-DBTs) in n-hexadecane. The specific desulfurization activity for 2,4,6,8-tetraethyl DBT (C8-DBT) by DszC enzyme was about twice that for 4,6-dipropyl DBT (C6-DBT). However, the degradation rate of 2,4,6,8-tetraethyl DBT in n-hexadecane by resting cells of strain MR65 was only about 40% of that of 4,6-dipropyl DBT. These results indicated that the desulfurization ability for Cx-DBTs by resting cells depends on carbon number substituted at positions 4 and 6 and that the rate-limiting step in the desulfurization reaction of highly alkylated Cx-DBTs is the transfer process from the oil phase into the cell. 相似文献
998.
Kimiko Okabe Motohiro Hasegawa Hiroshi Makihara 《Journal of Insect Conservation》2017,21(5-6):771-779
Characterising geographic patterns of biodiversity generated by intrinsic distributions of organisms is essential for designing effective biodiversity conservation plans on both the project and sub-national to national scales. Species composition is generally similar within the same types of ecosystems located close to one another, but similarity also depends on the focal organism(s) as well as the scale of the analysis. To facilitate decision-making for environmental compensation projects such as “biodiversity offsets”, we examined whether Japanese ecoregions based on vegetation are correlated with the distribution of cerambycid beetles, using existing cerambycid data collected from Hokkaido to the Nansei Islands in both natural and plantation forests over 1 year in each area. At the national level, the species compositions of beetles were quite distinct in Hokkaido and the Nansei Islands but less so in other areas. The overall pattern of the observed sampling data fit that obtained by previously accumulated local inventories. At the area level (including plantation forests under different management regimes/successional stages and in some cases naturally regenerated mature to old growth forests), no consistent beetle composition patterns were observed, although compositions in natural forests and closed canopy/thinned/old growth plantation forests were sometimes distinct. Therefore, we conclude that when ecoregions are considered during decision-making for “no net-loss or net-gain” biodiversity conservation measures, it is important to examine multiple organisms on various scales using scientific approaches from several perspectives. 相似文献
999.
Y Kawasaki T Saitoh T Okabe K Kumakura M Ohara-Imaizumi 《Biochimica et biophysica acta》1991,1067(1):71-80
Secretory processes via exocytosis in rat peritoneal mast cells were visualized by two complementary fluorescence techniques; one staining pre-exocytotic granules with a basic probe and the other staining post-exocytotic granules with acidic probes. Granules within mast cells were selectively stained with acridine orange and emitted orange yellow fluorescence. Upon stimulation with compound 48/80, release of acridine orange from granules was observed both in population and single cell measurements. This release was seen in some localized area of mast cells. Opening of pores between plasma membranes and granule membranes was monitored using acidic fluorescence probes such as 6-carboxyfluorescein or lucifer yellow CH. Not only granules located at peripheral region, but also granules near the core region participated in exocytosis. The existence of junctions between these granules was suggested. TMA-DPH, a lipophilic membrane probe, which was localized at plasma membrane before stimulation, diffused into granule membranes after stimulation. This shows that after stimulation, some constituents of plasma and granule membranes were mixed. Even after extensive degranulation, mast cells extruded acidic probes, indicating the plasma membranes still play a role of barrier. Activation of lateral motion of granules preceding to exocytosis was not observed. It was concluded that the visualization of secretory processes by fluorescence and image processing techniques will be useful for the study of molecular mechanisms underlying exocytosis. 相似文献
1000.