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241.
Iino M Goto K Kakegawa W Okado H Sudo M Ishiuchi S Miwa A Takayasu Y Saito I Tsuzuki K Ozawa S 《Science (New York, N.Y.)》2001,292(5518):926-929
Glial cells express a variety of neurotransmitter receptors. Notably, Bergmann glial cells in the cerebellum have Ca2+-permeable alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA)-type glutamate receptors (AMPARs) assembled without the GluR2 subunit. To elucidate the role of these Ca2+-permeable AMPARs, we converted them into Ca2+-impermeable receptors by adenoviral-mediated delivery of the GluR2 gene. This conversion retracted the glial processes ensheathing synapses on Purkinje cell dendritic spines and retarded the removal of synaptically released glutamate. Furthermore, it caused multiple innervation of Purkinje cells by the climbing fibers. Thus, the glial Ca2+-permeable AMPARs are indispensable for proper structural and functional relations between Bergmann glia and glutamatergic synapses. 相似文献
242.
Shimizu-Ibuka A Nakai Y Nakamori K Morita Y Nakajima K Kadota K Watanabe H Okubo S Terada T Asakura T Misaka T Abe K 《Journal of agricultural and food chemistry》2008,56(13):5338-5344
Neoculin occurring in an edible tropical fruit is a heterodimeric protein which has both sweetness and a taste-modifying activity that converts sourness to sweetness. Both the primary and the overall tertiary structures of neoculin resemble those of monocot mannose-binding lectins. This study investigated differences in biochemical properties between neoculin and the lectins. Structural comparison between the mannose-binding sites of lectins and the corresponding regions of neoculin showed that there is at least one amino acid substitution at each site in neoculin, suggesting a reason for the lack of its mannose-binding ability. This was consistent with hemagglutination assay data demonstrating that neoculin had no detectable agglutinin activity. DNA microarray analysis indicated that neoculin had no significant influence on gene expression in Caco-2 cell, whereas kidney bean lectin (Phaseolus vulgaris agglutinin) greatly influenced various gene expressions. These data strongly suggest that neoculin has no lectin-like properties, encouraging its practical use in the food industry. 相似文献
243.
Nakagawa K Umeda T Higuchi O Tsuzuki T Suzuki T Miyazawa T 《Journal of agricultural and food chemistry》2006,54(7):2479-2483
Broccoli sulforaphane has received attention as a possible anticarcinogen. Sulforaphane analysis is difficult due to the lack of a chromophore for spectrometric detection. Hence, we developed a method for determining sulforaphane by using high-performance liquid chromatography (HPLC) coupled with an evaporative light-scattering detector (ELSD). Sulforaphane was extracted from acid-hydrolyzed broccoli samples, followed by solid-phase extraction and reversed-phase HPLC. Sulforaphane was detected by ELSD and concurrently identified by electrospray ionization time-of-flight mass spectrometry. The recovery of sulforaphane from broccoli samples was above 95%. The detection limit was 0.5 mug. The present method was sensitive enough to determine sulforaphane in mature broccoli, broccoli sprouts, and commercial broccoli products. Sulforaphane concentration in broccoli sprout (1153 mg/100 g dry weight) was about 10 times higher than that of mature broccoli (44-171 mg/100 g dry weight). Therefore, the broccoli sprout is recommended as a source of sulforaphane-rich products. In contrast, we found that sulforaphane could not be detected in most of broccoli products, suggesting present commercial broccoli products having low quality. 相似文献
244.
Zolensky ME Zega TJ Yano H Wirick S Westphal AJ Weisberg MK Weber I Warren JL Velbel MA Tsuchiyama A Tsou P Toppani A Tomioka N Tomeoka K Teslich N Taheri M Susini J Stroud R Stephan T Stadermann FJ Snead CJ Simon SB Simionovici A See TH Robert F Rietmeijer FJ Rao W Perronnet MC Papanastassiou DA Okudaira K Ohsumi K Ohnishi I Nakamura-Messenger K Nakamura T Mostefaoui S Mikouchi T Meibom A Matrajt G Marcus MA Leroux H Lemelle L Le L Lanzirotti A Langenhorst F Krot AN Keller LP Kearsley AT 《Science (New York, N.Y.)》2006,314(5806):1735-1739
The bulk of the comet 81P/Wild 2 (hereafter Wild 2) samples returned to Earth by the Stardust spacecraft appear to be weakly constructed mixtures of nanometer-scale grains, with occasional much larger (over 1 micrometer) ferromagnesian silicates, Fe-Ni sulfides, Fe-Ni metal, and accessory phases. The very wide range of olivine and low-Ca pyroxene compositions in comet Wild 2 requires a wide range of formation conditions, probably reflecting very different formation locations in the protoplanetary disk. The restricted compositional ranges of Fe-Ni sulfides, the wide range for silicates, and the absence of hydrous phases indicate that comet Wild 2 experienced little or no aqueous alteration. Less abundant Wild 2 materials include a refractory particle, whose presence appears to require radial transport in the early protoplanetary disk. 相似文献
245.
João Costa Filho Mônica Yumi Tsuzuki Giovanni Lemos de Mello Luiz Cláudio Miletti Karim Hahn Lüchmann Carlos André da Veiga Lima-Rosa 《Journal Of Applied Aquaculture》2017,29(3-4):199-206
We investigated the growth of juvenile common snook (Centropomus undecimalis) reared at 25°C and 28°C and salinities of 0.3, 15, and 32 g L?1. Total length, weight, RNA/DNA, and protein/DNA ratios were determined after 90 days of experiment. Higher growth was observed at 28ºC compared with 25°C, at the same salinity. At 28°C and 15 g L?1 salinity, the weight (25.14 g) of juveniles was twice that of the juveniles reared at the lower temperature. At different salinities, only higher temperature affected growth, with higher weight values obtained at 15 g L?1 in comparison with 0.3 and 32 g L?1. Length was similar at 0.3 and 15 g L?1. The RNA/DNA ratio was greater in juveniles reared at a salinity of 15 g L?1 when compared with 0.3 and 32 g L?1. This study shows that the combination of higher temperature and intermediate salinity promotes better growth of common snook juveniles. 相似文献
246.
Green tea consumption in everyday life and mental health 总被引:1,自引:0,他引:1
Shimbo M Nakamura K Jing Shi H Kizuki M Seino K Inose T Takano T 《Public health nutrition》2005,8(8):1300-1306
OBJECTIVE: Green tea has been widely acknowledged in Japan to induce a pleasurable mental feeling. Recent laboratory studies have suggested positive psychological effects as a result of consuming green tea. The present study examined whether green tea consumption in everyday life in Japan is associated with positive mental health. DESIGN: A cross-sectional study was performed in February-March 2002. SETTING AND SUBJECTS: The subjects of the study consisted of a general population of 600 Japanese aged 20-69 years. Responses of 380 subjects, obtained by home-visit interview, were analysed. The questionnaire inquired about consumption of brewed green tea and other beverages, perceived mental health status, lifestyle and others. The 12-item General Health Questionnaire (GHQ 12) was used for the assessment of mental ill-health (GHQ score >or=4). RESULTS: After adjustments for age, area, perceived mental stress, lifestyle and daily caffeine intake, the consumption of brewed green tea was not statistically associated with any decrease in risk of mental ill-health among either males or females (odds ratio (OR)=0.78, 95% confidence interval (CI)=0.47-1.29 for males; OR=0.77, 95% CI=0.51-1.14 for females). Daily caffeine intake (100 mg) inclusive of green tea, black tea, coffee and other caffeine-containing beverages was associated with a higher risk of mental ill-health among females (OR=1.26, 95% CI=1.01-1.56). CONCLUSIONS: The results provide population-based evidence on the consumption of brewed green tea in everyday life and mental health, together with information on consumption patterns of various beverages and lifestyles. 相似文献
247.
Trimethylamine-N-oxide (TMAO) degrades to dimethylamine (DMA) and formaldehyde, which cause a decline in fish quality. Suppression of DMA
formation in frozen surimi was investigated using croaker, lizardfish, and walleye pollock. The leaching process in surimi
processing was shown to reduce not only the TMAO, iron, and taurine content, but also to reduce unidentified factors that
accelerate DMA formation in lizardfish muscle; in contrast, unidentified factors that suppress DMA formation were reduced
in croaker and pollock muscle. Sucrose, used as a cryoprotectant, was shown to decrease DMA formation in vitro, likely due
to the reduction in freezing-induced concentration of solutes. The effects of pH on DMA formation were different in minced
frozen meat among the three species. DMA formation was not observed in croaker when the pH varied between 6 and 8. On the
other hand, DMA was elevated in lizardfish under acidic conditions, and DMA formation in pollock was maximal when the pH of
the meat was neutral. Thus, the suppression of TMAO degradation by surimi processing results from the removal of TMAO, iron,
and reductants from fish meat; sucrose also reduces DMA formation. Furthermore, unidentified factors in croaker, lizardfish,
and pollock meat substantially affect DMA formation. 相似文献
248.
Masashi Ando Yoko Nakagishi Keiko Yoshida Masashi Nakao Takayuki Nakagawa Yasuo Makinodan Yasuyuki Tsukamasa Ken-Ichi Kawasaki 《Fisheries Science》2006,72(5):1104-1108
Pyridinoline (Pyr), one of the mature crosslinks of collagen, was determined in muscular collagen of three species of fish.
The amounts of muscular Pyr in red sea bream, yellowtail, and tiger puffer were 3.4, 8.8, and 50.3 mmol/mol collagen, respectively,
indicating that the Pyr concentration in muscular collagen differs greatly among fish species. The Pyr concentration in tiger
puffer muscular collagen was the greatest, but it was only one-fourth that in rabbit muscle. As in mammalian skin collagen,
Pyr was not detected in skin collagen of red sea bream and yellowtail. However, tiger puffer skin contained Pyr (3.75 mmol/mol
collagen). The presence of Pyr would have a relationship to some features of tiger puffer skin, such as mechanical strength
and thickness. Pyr concentrations in acid-soluble collagen (ASC), pepsin-solubilized collagen (PSC), and insoluble collagen
(ISC) in muscles of three species of fish were determined. Pyr was found in ISC > PSC > ASC, from the highest to the lowest
concentration, and the concentration in ISC was 45–200 times that in ASC. Therefore, Pyr crosslinks that are formed between
collagen molecules would have a close relationship to collagen solubility. 相似文献