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951.
952.
Uy MM Ohta S Yanai M Ohta E Hirata T Ikegami S 《Bioorganic & medicinal chemistry letters》2002,12(21):3037-3039
A new nitrogen-containing bicyclic spirosesquiterpene designated exiguamide which inhibited cell fate specification during sea urchin embryogenesis has been isolated from the marine sponge Geodia exigua. Its structure was determined by interpretation of spectral data and X-ray crystallographic analysis. 相似文献
953.
Luigi Ferrucci John R.B. Perry Amy Matteini Markus Perola Toshiko Tanaka Kaisa Silander Neil Rice David Melzer Anna Murray Christie Cluett Linda P. Fried Demetrius Albanes Anna-Maria Corsi Antonio Cherubini Jack Guralnik Stefania Bandinelli Andrew Singleton Jarmo Virtamo Jeremy Walston Richard D. Semba Timothy M. Frayling 《American journal of human genetics》2009,84(2):123-133
Low plasma levels of carotenoids and tocopherols are associated with increased risk of chronic disease and disability. Because dietary intake of these lipid-soluble antioxidant vitamins is only poorly correlated with plasma levels, we hypothesized that circulating carotenoids (vitamin A-related compounds) and tocopherols (vitamin E-related compounds) are affected by common genetic variation. By conducting a genome-wide association study in a sample of Italians (n = 1190), we identified novel common variants associated with circulating carotenoid levels and known lipid variants associated with α-tocopherol levels. Effects were replicated in the Women's Health and Aging Study (n = 615) and in the α-Tocopherol, β-Carotene Cancer Prevention (ATBC) study (n = 2136). In meta-analyses including all three studies, the G allele at rs6564851, near the β-carotene 15,15′-monooxygenase 1 (BCMO1) gene, was associated with higher β-carotene (p = 1.6 × 10−24) and α-carotene (p = 0.0001) levels and lower lycopene (0.003), zeaxanthin (p = 1.3 × 10−5), and lutein (p = 7.3 × 10−15) levels, with effect sizes ranging from 0.10–0.28 SDs per allele. Interestingly, this genetic variant had no significant effect on plasma retinol (p > 0.05). The SNP rs12272004, in linkage disequilibrium with the S19W variant in the APOA5 gene, was associated with α-tocopherol (meta-analysis p = 7.8 × 10−10) levels, and this association was substantially weaker when we adjusted for triglyceride levels (p = 0.002). Our findings might shed light on the controversial relationship between lipid-soluble anti-oxidant nutrients and human health. 相似文献
954.
955.
956.
957.
Hirata M Amano K Miyashita A Yasunaga M Nakanishi T Sato K 《Journal of biochemistry》2009,145(1):51-58
The liver is a unique organ with the potential to regenerate from injury. Hepatic stem cells contribute to liver regeneration when surviving hepatocytes in injured liver are unable to proliferate. To investigate the mechanism of liver regeneration in vitro, we established hepatic stem cell lines named HY1, HY2 and HY3, derived from a healthy liver of adult rat. HY cells showed an expression pattern similar to oval cells, and efficiently induced hepatic differentiation following sequential treatment with type I collagen, transforming growth factor-beta1 (TGF-beta1), and hepatocyte growth factor (HGF) or oncostatin M (OSM). These results suggested that HY cells are liver stem cells representing an excellent tool for in vitro studies on liver regeneration. 相似文献
958.
Masahiko Hirata Nobumi Hasegawa Kangoro Nogami Tatsunobu Sonoda 《Journal of Ethology》2009,27(3):437-445
This 4-year study monitored maintenance behavior of beef cattle (Japanese Black) foraging in a young Chamaecyparis obtusa (an evergreen conifer) plantation in southwestern Japan. The animals spent 551 ± 8 min (mean ± SE) per day grazing, 436 ± 4 min
ruminating, 313 ± 9 min resting, 44 ± 2 min moving, and 96 ± 4 min on other activities. Grazing activity was high during 0600–1800 h
and low during 2200–0600 h. Ruminating activity was high during 2200–0600 h and low during 0600–1800 h. Resting activity was
high during 2200–0600 h and low for the remainder of the day. Air temperature was not a dominant factor determining the daily
duration of grazing, rumination, or resting. The activity of the animals was usually synchronized, with the degree of synchronization
being highest in grazing followed by ruminating and resting. Daily liveweight change of the animals was positively related
with daily ruminating time, i.e., animals gained more when they ruminated longer. The maintenance behavior of cattle in the
young tree plantation, as compared with that on grasslands, is characterized by (1) high grazing activity around midday, (2)
low ruminating activity in the daytime, and (3) midday adjustment of the daily total grazing time. Daily rumination time may
be used as an indicator of animal performance on the bases of a herd (not individual animals) and a period of 2–15 weeks (not
individual days). 相似文献
959.
We found alpha-glucosidase inhibitory (α-GI) effect of metal ions and their complexes which showed the high blood glucose lowering effect in diabetic model animals. The Cu(II) ion and its complexes showed strong α-GI activity greater than clinically used acarbose in in vitro studies. Furthermore, in in vivo experiments, α-GI action was newly discovered in normal ddy mice. These results suggested that one of action mechanisms of the anti-diabetic metal ions and complexes is related to the α-GI effects. 相似文献
960.
Tony Marcio da Silva Alexandre Maller André Ricardo de Lima Damásio Michele Michelin Richard John Ward Izaura Yoshico Hirata João Atilio Jorge Héctor Francisco Terenzi Maria Lourdes T. M. de Polizeli 《Journal of industrial microbiology & biotechnology》2009,36(12):1439-1446
A glucoamylase from Aspergillus niveus was produced by submerged fermentation in Khanna medium, initial pH 6.5 for 72 h, at 40°C. The enzyme was purified by DEAE-Fractogel
and Concanavalin A-Sepharose chromatography. The enzyme showed 11% carbohydrate content, an isoelectric point of 3.8 and a
molecular mass of 77 and 76 kDa estimated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis or Bio-Sil-Sec-400
gel filtration, respectively. The pH optimum was 5.0–5.5, and the enzyme remained stable for at least 2 h in the pH range
of 4.0–9.5. The temperature optimum was 65°C and retained 100% activity after 240 min at 60°C. The glucoamylase remained completely
active in the presence of 10% methanol and acetone. After 120 min hydrolysis of starch, glucose was the unique product formed,
confirming that the enzyme was a glucoamylase (1,4-alpha-d-glucan glucohydrolase). The K
m was calculated as 0.32 mg ml−1. Circular dichroism spectroscopy estimated a secondary structure content of 33% α-helix, 17% β-sheet and 50% random structure,
which is similar to that observed in the crystal structures of glucoamylases from other Aspergillus species. The tryptic peptide sequence analysis showed similarity with glucoamylases from A. niger, A. kawachi,
A. ficcum, A. terreus, A. awamori and A. shirousami. We conclude that the reported properties, such as solvent, pH and temperature stabilities, make A. niveus glucoamylase a potentially attractive enzyme for biotechnological applications. 相似文献