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961.
Naoki Maeda Yasuo Kokai Seiji Ohtani Takahiko Hada Hiromi Yoshida Yoshiyuki Mizushina 《Food chemistry》2009
The glycoglycerolipid fraction from spinach was purified, and this fraction was used to clarify bioactive functions, such as inhibition of DNA polymerase activity and cancer cell growth. The effects of the spinach glycoglycerolipid fraction on preventive and curative antitumor activities, and acute toxicity were investigated. After oral administration of 20 mg/kg of the glycoglycerolipid fraction for 2 weeks as preliminary medication, colon tumor growth was delayed, and the protein expression level of proliferating cell nuclear antigen (PCNA) was decreased in tumor tissue. Five days after tumor cell implantation, oral administration of, not only 70 mg/kg of the glycoglycerolipid fraction, but also the γ-cyclodextrin (CD) glycoglycerolipid fraction complex, for 4 weeks, suppressed sarcoma formation with no adverse reactions in mice. In the acute toxicity test, 2000 mg/kg of orally administered glycoglycerolipid fraction did not show evident toxicity. Hence, these results suggest that the spinach glycoglycerolipid fraction is a safe and effective anticancer bioactive agent and/or food material. 相似文献
962.
Global harmonization of food safety regulations: perspectives from Japan after the Fukushima nuclear accident 下载免费PDF全文
Mitsuru Yoshida 《Journal of the science of food and agriculture》2014,94(10):1938-1940
Japanese food self‐sufficiency was only 39% on the basis of kcal in 2012, so Japan relies heavily on imported food. Hence the necessity of having international rules on the regulation of food contaminants is important especially for countries like Japan that depend on food imports. A One‐Stop‐Testing system is desired, in which the test result obtained from a single testing laboratory is accepted as valid worldwide. To establish this system, laboratory accreditation under international standards is a necessary step. Furthermore, the importance of supply of reference materials for internal quality control and proficiency testing for external quality control of each laboratory's analytical system is reviewed in connection with the experience of radioactive nuclide contamination resulting from the Fukushima nuclear power plant accident in March 2011. © 2013 Society of Chemical Industry 相似文献
963.
Teruo Nagaya Hideyo Yoshida Hidekatsu Takahashi Makoto Kawai 《Nicotine & tobacco research》2007,9(10):1027-1032
To investigate the longitudinal impact of smoking cessation and relapse on the exercise habits of apparently healthy Japanese men, 750 subjects presenting for a checkup at a metropolitan health center were surveyed annually for 7 years. Exercise was dichotomously classified as none or any. Subjects were grouped in two categories: 98 smokers who ceased smoking during the second year of the study, matched with 196 continuing smokers and 196 men who had never smoked; and 52 relapsed smokers (including 2 new smokers) who did not smoke at baseline or at Year 1 but smoked from Year 2 to final follow-up, matched with 104 continuing smokers and 104 never-smokers. Based on self-reported responses to questionnaires, exercise was consistently less prevalent among smokers who did not quit than among never-smokers throughout the study. Habitual exercise in subjects who had quit smoking increased during the follow-up (any exercise: 42.9% at baseline increased to 51% at final follow-up, p for longitudinal trend = .115). Habitual exercise in matched never-smokers did not change during the study and decreased significantly among persistent smokers (p = .025). Habitual exercise in relapsed smokers decreased during the follow-up (any exercise: 50.0% at baseline declined to 32.7% at final follow-up, p = .007), but habitual exercise in matched persistent smokers and never-smokers did not change. We conclude that smoking and sedentary lifestyle coexist continuously, that smoking cessation is associated with increased habitual exercise among healthy men, and that relapse is associated with reduced habitual exercise, suggesting that cigarette smoking weakens exercise habits. 相似文献
964.
Nakano A Lee CY Yoshida A Matsumoto T Shiomi N Katoh S 《Journal of Bioscience and Bioengineering》2006,101(3):227-231
The effects of two types of methanol feeding methods in a continuous culture of Pichia system on the cell growth and recombinant protein expression were studied using chimeric alpha-amylase as a model protein. With the feeding of methanol by a DO-stat method, the alpha-amylase concentration in the fermentation broth increased with decreasing dilution rate and reached 173 mg/l at a dilution rate of 0.013 h(-1), at which the maximum volumetric productivity of alpha-amylase was obtained. Although almost the same productivity was attained at 0.04 h(-1) with continuous methanol feeding, the alpha-amylase concentration was one third that compared with feeding by the DO-stat method, that is, 55 mg/l. Furthermore, at this dilution rate, the medium volume needed per unit time was three times that required when DO-stat was used. Therefore, continuous culture with methanol feeding by the DO-stat method may be a promising method for the production of recombinant proteins on an industrial scale by Pichia pastoris. 相似文献
965.
Variation of the gel region with heat-treatment and variation of the melt-quenched glass region with cooling rates were compared for the B2O3-Na2O-TiO2 system. Gels were prepared by the sol-gel method without catalyst using boron tributoxide (B(OBu)3) sodium methoxide (NaOCH3) and titanium tetraisopropoxide (Ti(OPr)4). The gel region was in the composition range B2O3 = 0 to 90, Na2O = 0 to 60, and TiO2 = 0 to 100 mol % at 50 ° C. The crystalline phases precipitated were boric acid (H3BO3), sodium metaborate hydrate (NaBO22H2O), and sodium hydroxide (NaOH), or sodium carbonate (Na2CO3). A 500 °C, heat treatment for 2 h reduced the gel regions to a composition range of B2O3 = 50 to 90, Na2O = 10 to 30 and TiO2 = 0 to 20 mol %, but treatment at 800 ° C produced melts which became glassy upon cooling. On the other hand, a twin-roller method produced a wide range of glass region which includes a high concentration of TiO2 up to 70 mol %. The as-prepared gel region was found to correspond fairly well to the twin-roller glass region and the thermally most stable gel region was close to the air-quenched glass region. It was speculated that the B2O3- or Na2O-rich composition had not gelled because of the high water solubility of these gels. 相似文献
966.
Hydroxyethyl starch (HES) was isolated from blood and urine, and also limit HES was isolated which was obtained by exhaustive degradation of HES by α-amylase. From the study on their physicochemical properties and molecular-size distributions, the results were obtained that [η] and molecular substitution (M. S.) of HES isolated from the blood were almost unchanged, while [η] of HES isolated from urine was decreased and M. S. of it was slightly changed. Furthermore, it was calculated that limit HES contained only about 1.5% of higher-molecular-weight fractions against the amount of parent HES than those of HES excreted in urine. 相似文献
967.
Kazufumi Nakamura Toru Miyoshi Masashi Yoshida Satoshi Akagi Yukihiro Saito Kentaro Ejiri Naoaki Matsuo Keishi Ichikawa Keiichiro Iwasaki Takanori Naito Yusuke Namba Masatoki Yoshida Hiroki Sugiyama Hiroshi Ito 《International journal of molecular sciences》2022,23(7)
There is a close relationship between diabetes mellitus and heart failure, and diabetes is an independent risk factor for heart failure. Diabetes and heart failure are linked by not only the complication of ischemic heart disease, but also by metabolic disorders such as glucose toxicity and lipotoxicity based on insulin resistance. Cardiac dysfunction in the absence of coronary artery disease, hypertension, and valvular disease is called diabetic cardiomyopathy. Diabetes-induced hyperglycemia and hyperinsulinemia lead to capillary damage, myocardial fibrosis, and myocardial hypertrophy with mitochondrial dysfunction. Lipotoxicity with extensive fat deposits or lipid droplets is observed on cardiomyocytes. Furthermore, increased oxidative stress and inflammation cause cardiac fibrosis and hypertrophy. Treatment with a sodium glucose cotransporter 2 (SGLT2) inhibitor is currently one of the most effective treatments for heart failure associated with diabetes. However, an effective treatment for lipotoxicity of the myocardium has not yet been established, and the establishment of an effective treatment is needed in the future. This review provides an overview of heart failure in diabetic patients for the clinical practice of clinicians. 相似文献
968.
Naoto Yoshinaga Takaaki Miyamoto Masaki Odahara Noriko Takeda-Kamiya Kiminori Toyooka Seia Nara Haruna Nishimura Feng Ling Masayuki Su'etsugu Minoru Yoshida Keiji Numata 《Advanced functional materials》2024,34(8):2306070
Mitochondria are vital organelles regulating essential cellular functions. Human mitochondrial DNA (mtDNA) consists of 37 genes, 13 of which encode mitochondrial proteins, and the remaining 24 genes encode two ribosomal RNAs and 22 transfer RNAs needed for the translation of the mtDNA-encoded 13 proteins. However, mtDNA often impairs the expression and function of these genes due to various mutations, ultimately causing mitochondrial dysfunction. To recover from this desperate condition, developing the technology to supply all mitochondrial proteins encoded by mtDNA at once is an urgent task, but there is no established strategy for this purpose. In this study, a simple yet effective mitochondrial gene delivery system is proposed comprising an artificial peptide inspired by a transmembrane mitochondrial membrane protein. The designed mitochondria-targeting peptides presented on the carrier surface effectively guide the encapsulated plasmid to the mitochondria, facilitating mitochondrial uptake and gene expression. The developed system successfully delivers exogenous mtDNA to mtDNA-depleted cells and leads to simultaneous multigene expression, ultimately restoring mitochondrial functions, including the mitochondrial respiration rate. The established multiple gene expression system in each mitochondrion is a game-changing technology that can accelerate the development of mitochondrial engineering technologies as well as clinical applications for mitochondrial diseases. 相似文献
969.
Sakai M Hashimoto A Yoshida N Suzuki S Kameshima Y Nakajima A 《The Review of scientific instruments》2007,78(4):045103
An analysis system was developed to evaluate the sliding behavior of a liquid droplet on a hydrophobic surface. This system enables continuous and simultaneous measurement of both the sliding acceleration and shape deformation during the sliding of a liquid droplet. Moreover, the velocity vector of the internal fluidity of a sliding droplet was obtained by employing particle image velocimetry in the analysis system. This evaluation method pioneers the measurement of the dynamic wettability of a hydrophobic solid surface. 相似文献
970.
Ryutaro Yoshida Yoshihiko Yano Namiko Hoshi Norihiro Okamoto Yunlong Sui Atsushi Yamamoto Naoki Asaji Yuuki Shiomi Eiichiro Yasutomi Yuri Hatazawa Hiroki Hayashi Yoshihide Ueda Yuzo Kodama 《Journal of food science》2022,87(5):2173-2184
Resistant starch (RS) has been reported to improve steatosis as well as obesity. Type 4 resistant starch (RS4), a chemically modified starch, is particularly hard to digest and suggesting higher efficacy. However, because the effects of RS4 on steatosis are not yet fully understood, the effects of RS4 on steatosis were examined using a murine high-fat diet model. Seven-week-old male mice were divided into three groups and fed a normal diet, a high-fat diet (HFD), or a high-fat diet with added RS (HFD + RS). Amylofiber SH® produced from acid-treated corn starch was used as the dietary RS. At 22 weeks old, hepatic steatosis and short chain fatty acid (SCFA) content and gut microbiota in cecum stool samples were analyzed. The ratio of body weight to 7 weeks was significantly suppressed in the HFD + RS group compared to the HFD group (132.2 ± 1.4% vs. 167.2 ± 3.9%, p = 0.0076). Macroscopic and microscopic steatosis was also suppressed in the HFD + RS group. Analysis of cecum stool samples revealed elevated SCFA levels in the HFD + RS group compared with the HFD group. Metagenome analysis revealed that Bifidobacterium (17.9 ± 1.9% vs. 3.6 ± 0.7%, p = 0.0019) and Lactobacillus (14.8 ± 3.4% vs. 0.72 ± 0.23%, p = 0.0045), which degrade RS to SCFA, were more prevalent in the HFD + RS group than the HFD group. In conclusion, RS4 suppressed steatosis, and increased Bifidobacterium and Lactobacillus, and SCFAs. RS4 may prevent steatosis by modulating the intestinal environment. 相似文献