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71.
Yuji Koide Mamoru Honma Tokuji Shimomura 《Bioscience, biotechnology, and biochemistry》2013,77(3):775-776
Modified fungal product 4-O-methylascochlorin (MAC) is an experimental agent affecting lipid and carbohydrate metabolism in mammals. The hypocholesterolemic properties of MAC were studied using rats fed on a standard laboratory diet. Because of the insolubility in water, reproducibility of the hypocholesterolemic activity had usually been poor for rats fed ad libitum. The difficulty was overcome by controlled reverse-phase feeding; MAC significantly lowered serum total cholesterol (s-TC) in rats only when given by gastric intubation soon after diet intake.MAC increased fecal excretion of neutral and acidic sterols and also increased biliary flow accompanying increments in biliary cholesterol, bile acids and phospholipids. A much larger increase in neutral sterols was characteristic for MAC. However, intestinal absorption of cholesterol and cholic acid was unaffected by MAC. Three mechanisms therefore seemed to be working in hypocholesterolemic activity: (a) withdrawal of hepatic cholesterol into bile, (b) a larger fecal loss of sterols following increment of biliary sterols and (c) enhanced bile acid synthesis compensating the larger fecal loss. A negative sterol balance often leads to an increase in hepatic cholesterogenesis. However, cholesterogenesis, as judged from incorporation of the precursors, was unchanged by MAC. 相似文献
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75.
Kazunori Sasaki Tomoyuki Oki Yumi Kai Yoichi Nishiba 《Bioscience, biotechnology, and biochemistry》2013,77(8):1308-1314
The purpose of this study was to investigate the effect of repeated harvesting on the content of caffeic acid (CA) and seven species of caffeoylquinic acids (CQAs) in sweet potato leaves using a newly developed high-performance liquid chromatography method. Six cultivars and two breeding lines were used in this study. Leaves were collected at monthly intervals from 1st harvest (May) to 4th harvest (August) in 2011 and 2012. ANOVA analysis revealed that the contents of CQAs were significantly different among all cultivars and breeding lines, but no significant differences were found for CA. No annual variation was confirmed in CA and CQAs. Repeated harvest of sweet potato leaves affected the content of only 4-CQA and 5-CQA. Post-hoc comparisons using Tukey’s method indicated that the contents of 4-CQA and 5-CQA in sweet potato leaves harvested at first time were significantly higher compared to those at the other harvest times. 相似文献
76.
Hitomi Yatsuki Ken Higashimoto Kosuke Jozaki Kayoko Koide Junichiro Okada Yoriko Watanabe Nobuhiko Okamoto Yoshinobu Tsuno Yoko Yoshida Kazutoshi Ueda Kenji Shimizu Hirofumi Ohashi Tsunehiro Mukai Hidenobu Soejima 《Genes & genomics.》2013,35(2):141-147
Beckwith-Wiedemann syndrome (BWS) is an imprinting-related human disease that is characterized by macrosomia, macroglossia, abdominal wall defects, and variable minor features. BWS is caused by several genetic/epigenetic alterations, such as loss of methylation at KvDMR1, gain of methylation at H19-DMR, paternal uniparental disomy of chromosome 11, CDKN1C mutations, and structural abnormalities of chromosome 11. CDKN1C is an imprinted gene with maternal preferential expression, encoding for a cyclin-dependent kinase (CDK) inhibitor. Mutations in CDKN1C are found in 40 % of familial BWS cases with dominant maternal transmission and in ~5 % of sporadic cases. In this study, we searched for CDKN1C mutations in 37 BWS cases that had no evidence for other alterations. We found five mutations—four novel and one known—from a total of six patients. Four were maternally inherited and one was a de novo mutation. Two frame-shift mutations and one nonsense mutation abolished the QT domain, containing a PCNA-binding domain and a nuclear localization signal. Two missense mutations occurred in the CDK inhibitory domain, diminishing its inhibitory function. The above-mentioned mutations were predicted by in silico analysis to lead to loss of function; therefore, we strongly suspect that such anomalies are causative in the etiology of BWS. 相似文献
77.
Akihito Tanaka Knut Woltjen Katsuya Miyake Akitsu Hotta Makoto Ikeya Takuya Yamamoto Tokiko Nishino Emi Shoji Atsuko Sehara-Fujisawa Yasuko Manabe Nobuharu Fujii Kazunori Hanaoka Takumi Era Satoshi Yamashita Ken-ichi Isobe En Kimura Hidetoshi Sakurai 《PloS one》2013,8(4)
The establishment of human induced pluripotent stem cells (hiPSCs) has enabled the production of in vitro, patient-specific cell models of human disease. In vitro recreation of disease pathology from patient-derived hiPSCs depends on efficient differentiation protocols producing relevant adult cell types. However, myogenic differentiation of hiPSCs has faced obstacles, namely, low efficiency and/or poor reproducibility. Here, we report the rapid, efficient, and reproducible differentiation of hiPSCs into mature myocytes. We demonstrated that inducible expression of myogenic differentiation1 (MYOD1) in immature hiPSCs for at least 5 days drives cells along the myogenic lineage, with efficiencies reaching 70–90%. Myogenic differentiation driven by MYOD1 occurred even in immature, almost completely undifferentiated hiPSCs, without mesodermal transition. Myocytes induced in this manner reach maturity within 2 weeks of differentiation as assessed by marker gene expression and functional properties, including in vitro and in vivo cell fusion and twitching in response to electrical stimulation. Miyoshi Myopathy (MM) is a congenital distal myopathy caused by defective muscle membrane repair due to mutations in DYSFERLIN. Using our induced differentiation technique, we successfully recreated the pathological condition of MM in vitro, demonstrating defective membrane repair in hiPSC-derived myotubes from an MM patient and phenotypic rescue by expression of full-length DYSFERLIN (DYSF). These findings not only facilitate the pathological investigation of MM, but could potentially be applied in modeling of other human muscular diseases by using patient-derived hiPSCs. 相似文献
78.
Kazunori Ohkawara Marc‐Andre Cornier Wendy M. Kohrt Edward L Melanson 《Obesity (Silver Spring, Md.)》2013,21(2):336-343
Objective:
Consuming smaller, more frequent meals is often advocated as a means of controlling body weight, but studies demonstrating a mechanistic effect of this practice on factors associated with body weight regulation are lacking. The purpose of this study was to compare the effect of consuming three (3M) vs. six meals (6M) per day on 24‐h fat oxidation and subjective ratings of hunger.Design and Methods:
Lean (body mass index <25 kg/m2) subjects (7M, 8F) were studied in a whole‐room calorimeter on two occasions in a randomized cross‐over design. Subjects were provided isoenergetic, energy balanced diets with a 1‐ to 2‐week washout between conditions. Hunger, fullness, and “desire to eat” ratings were assessed throughout the day using visual analog scales and quantified as area under the curve (AUC).Results:
There were no differences (P < 0.05) in 24‐h energy expenditure (8.7 ± 0.3 vs. 8.6 ± 0.3 mj d?1), 24‐h respiratory quotient (0.85 ± 0.01 vs. 0.85 ± 0.01), or 24‐h fat oxidation (82 ± 6 vs. 80 ± 7 g day‐1) between 3M and 6M, respectively. There was no difference in fullness 24‐h AUC, but hunger AUC (41850 ± 2255 vs. 36612 ± 2556 mm.24 h, P = 0.03) and “desire to eat” AUC (47061 ± 1791 vs. 41170 ± 2574 mm.24 h, P = 0.03) were greater during 6M than 3M.Conclusion:
We conclude that increasing meal frequency from three to six per day has no significant effect on 24‐h fat oxidation, but may increase hunger and the desire to eat.79.
Band Edge Engineering of Oxide Photoanodes for Photoelectrochemical Water Splitting: Integration of Subsurface Dipoles with Atomic‐Scale Control
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Yasuyuki Hikita Kazunori Nishio Linsey C. Seitz Pongkarn Chakthranont Takashi Tachikawa Thomas F. Jaramillo Harold Y. Hwang 《Liver Transplantation》2016,6(7)
One of the crucial parameters dictating the efficiency of photoelectrochemical water‐splitting is the semiconductor band edge alignment with respect to hydrogen and oxygen redox potentials. Despite the importance of metal oxides in their use as photoelectrodes, studies to control the band edge alignment in aqueous solution have been limited predominantly to compound semiconductors with modulation ranges limited to a few hundred mV. The ability to modulate the flat band potential of oxide photoanodes by as much as 1.3 V, using the insertion of subsurface electrostatic dipoles near a Nb‐doped SrTiO3/aqueous electrolyte interface is reported. The tunable range achieved far exceeds previous reports in any semiconductor/aqueous electrolyte system and suggests a general design strategy for highly efficient oxide photoelectrodes. 相似文献
80.
Yoshiko Onda Rimei Nishimura Aya Morimoto Hironari Sano Kazunori Utsunomiya Naoko Tajima The Diabetes Epidemiology Research International Mortality Study Group 《PloS one》2016,11(3)