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排序方式: 共有918条查询结果,搜索用时 21 毫秒
51.
Sayuri L. Higashi Normazida Rozi Sharina Abu Hanifah Masato Ikeda 《International journal of molecular sciences》2020,21(24)
Supramolecular architectures that are built artificially from biomolecules, such as nucleic acids or peptides, with structural hierarchical orders ranging from the molecular to nano-scales have attracted increased attention in molecular science research fields. The engineering of nanostructures with such biomolecule-based supramolecular architectures could offer an opportunity for the development of biocompatible supramolecular (nano)materials. In this review, we highlighted a variety of supramolecular architectures that were assembled from both nucleic acids and peptides through the non-covalent interactions between them or the covalently conjugated molecular hybrids between them. 相似文献
52.
Nongluk Sriwilaijaroen Akio Kadowaki Yuriko Onishi Nobuki Gato Makoto Ujike Takato Odagiri Masato Tashiro Yasuo Suzuki 《Food chemistry》2011
Fruit-juice concentrate of Japanese apricot (Prunus mume Sieb. et Zucc.) has been shown to be effective against influenza A infection in MDCK cells. In this study, we isolated five components from the fruit-juice concentrate of Japanese apricot, 5-(hydroxymethyl)-2-formylfuran (HMF), 1-[5-(2-formylfuryl)methyl]dihydrogen 2-hydroxypropane-1,2,3-tricarboxylate (mumefural, MF), 2-[5-(2-formylfuryl)methyl]dihydrogen 2-hydroxypropane-1,2,3-tricarboxylate (MF‘), 1-[5-(2-formylfuryl)methyl]hydrogen 1-hydroxyethane-1,2-dicarboxylate (MA1) and 2-[5-(2-formylfuryl)methyl]hydrogen 1-hydroxyethane-1,2-dicarboxylate (MA2), and investigated their inhibitory activities against the novel influenza A/Narita/1/2009 (H1N1) pandemic virus hemagglutinin and neuraminidase functions, which are essential for viral attachment and budding, respectively. An hemagglutination inhibition assay indicated that MF and MF‘ were effective at minimum hemagglutination concentrations of 3.1 and 6.3 mM, respectively. An inhibition study for sialidase activity of the neuraminidase spike showed that MF was the most active anti-sialidase compound with an IC50 value of 0.21 ± 0.01 mM, followed by MA2 (IC50, 0.71 ± 0.09 mM), MA1 (IC50, 1.64 ± 0.31 mM) and MF‘(IC50, 1.62 ± 0.22 mM). Furthermore, MF was shown to inhibit the growth of the pandemic virus in a dose-dependent manner (62 ± 3% inhibition at 5 mM). The results suggest that MF, a citric acid ester linked to HMF at the 1-position of the propane backbone, might be a lead compound for the development of anti-influenza A inhibitors. 相似文献
53.
Kaname Uno Shohei Iyoshi Masato Yoshihara Kazuhisa Kitami Kazumasa Mogi Hiroki Fujimoto Mai Sugiyama Yoshihiro Koya Yoshihiko Yamakita Akihiro Nawa Tomohiro Kanayama Hiroyuki Tomita Atsushi Enomoto Hiroaki Kajiyama 《International journal of molecular sciences》2022,23(8)
Epithelial ovarian cancer (EOC) is the most lethal gynecologic malignancy and has a unique metastatic route using ascites, known as the transcoelomic root. However, studies on ascites and contained cellular components have not yet been sufficiently clarified. In this review, we focus on the significance of accumulating ascites, contained EOC cells in the form of spheroids, and interaction with non-malignant host cells. To become resistant against anoikis, EOC cells form spheroids in ascites, where epithelial-to-mesenchymal transition stimulated by transforming growth factor-β can be a key pathway. As spheroids form, EOC cells are also gaining the ability to attach and invade the peritoneum to induce intraperitoneal metastasis, as well as resistance to conventional chemotherapy. Recently, accumulating evidence suggests that EOC spheroids in ascites are composed of not only cancer cells, but also non-malignant cells existing with higher abundance than EOC cells in ascites, including macrophages, mesothelial cells, and lymphocytes. Moreover, hetero-cellular spheroids are demonstrated to form more aggregated spheroids and have higher adhesion ability for the mesothelial layer. To improve the poor prognosis, we need to elucidate the mechanisms of spheroid formation and interactions with non-malignant cells in ascites that are a unique tumor microenvironment for EOC. 相似文献
54.
Hideki Shige Toshitsugu Ishikawa Michio Suzukawa Masato Nishiwaki Takeshi Yamashita Kei Nakajima Toshimitsu Ito Kenji Higashi Makoto Ayaori Atsushi Yonemura Paul Nestel Haruo Nakamura 《Lipids》1998,33(12):1169-1175
The effects of vitamin E on cholesteryl ester (CE) metabolism in 1774 cells were examined. Pretreatment of 1774 cells with
vitamin E at concentrations above 50 μM significantly decreased acetylated low density lipoprotein (LDL)-induced incorporation
of [14C]oleate into CF in cells in a dose-dependent manner. This was partly due to vitamin E Also significantly inhibiting the uptake
of [3H]CE-labeled acetylated LDL by 1774 cells. A trend existed toward suppression of acyl-CoA:cholesterol acyltransferase (ACAT)
activity in the cell lysate at high vitamin E concentration, but there was no effect on hydrolysis of CE. These data indicate
that vitamin E reduces the uptake of modified LDL and suppresses ACAT activity, resulting in less cholesterol esterification
in macrophages; a novel mechanism underlying the antiatherogenic properties of vitamin E. 相似文献
55.
56.
Biodegradable plastics were synthesized for the effective use of sago starch‐extraction residue, which has been discarded as a waste. Two types of esterified sago starch‐extraction residue, P‐SP and L‐SP, were obtained. It had black color for P‐SP160 (esterified by palm oil) to light yellow color for L‐SP80 (esterified by lauric acid) and showed high carbon content, ranging from 399.3 to 537.1 g kg−1. Biodegradable plastics from the residue, which had high esterification degree showed thermoplasticity and slower decomposition in Andisols in Japan and Inceptisols in Philippines. The esterification degrees of P‐SP160 and L‐SP were 3.23 and 2.95 to 5.18 mmol g−1, respectively. In addition, L‐SP80 exhibited the most appropriate thermal softening behavior by heating. The cumulative decomposition of P‐SP160 in Andisols and Inceptisols showed 16.7 and 32.8% of total carbon during 31 day of the incubation. On the other hand, the decomposition rates of L‐SP80 in Andisols and Inceptisols were less than 10% of total carbon during 31 day of the incubation. The addition of triacetin as plasticizer to P‐SP160 and L‐SP80 remarkably influenced the decomposition rate of both molded P‐SP160 and L‐SP80. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 相似文献
57.
Yunosuke Abe Toshiki Aoki Hongge Jia Shingo Hadano Takeshi Namikoshi Yuriko Kakihana Lijia Liu Yu Zang Masahiro Teraguchi Takashi Kaneko 《Polymer》2012,53(11):2129-2133
A soluble and stable one-handed helical conjugated polymer without the coexistence of any other chiral moieties was successfully synthesized by asymmetric-induced polymerization of a chiral monomer having two hydroxyl groups followed by desubstitution of the chiral groups in a solid membrane state. The reason for the success was the polymer reaction was carried out in the membrane state. This is an alternative method to obtain such a unique chiral polymer which was obtained only by the helix-sense-selective polymerization (HSSP) we reported before. In addition the efficiency of the chiral induction was higher than that of the HSSP. It is interesting that the “Membrane state” acted like as if a protecting group. 相似文献
58.
Sliding friction tests of pin-on-disc type were carried out for carbon steel, pure iron and pure copper, and the microstructure and hardness near the sliding surfaces were investigated in detail. It was found that patchy transfer layers with ultra-fine (<200 nm) structures were produced on the disc surfaces. Nanocrystalline grains of 30–50 nm were identified for carbon steel, and submicron sized grains of 100–150 nm were observed in pure copper. The thicknesses of the ultra-fine structures were in the range of 10–50 μm, depending on the specimen material, sliding speed and applied load. The hardness near the sliding surface of pure iron was increased compared with the matrix. It was suggested that the hardening was due to the very fine structure formed by severe plastic deformation, but not due to phase transformation caused by thermal effects. 相似文献
59.
A methodology for realizing a higher‐power‐density DC‐DC converter has been proposed for a power unit installed in a 380‐V DC distribution system. The possibility of the converter design will be strengthened by using the series–parallel connection topology for isolated DC‐DC converters. A converter prototype with a power density of 10 W/cm3 has been fabricated, and the feasibility of the converter design has been confirmed experimentally. This result contributes to the realization of a highly efficient and highly space‐saving 380‐V DC distribution system. © 2013 Wiley Periodicals, Inc. Electr Eng Jpn, 186(3): 51–62, 2014; Published online in Wiley Online Library ( wileyonlinelibrary.com ). DOI 10.1002/eej.22494 相似文献
60.
EFFECT OF STEPWISE CHANGE OF DRYING RATE ON MICROSTRUCTURE EVOLUTION IN POLYMER FILMS 总被引:2,自引:0,他引:2
Masato Yamamura Takatoshi Nishio Toshihisa Kajiwara Kitaro Adachi 《Drying Technology》2001,19(7):1397-1410
The effect of the drying rate of the solvent on microstructure evolution in thin films of immiscible polystyrene/polycarbonate blends was investigated by applying a stepwise change in air velocity. The polymer blend was dissolved in tetrahydrofuran and cast on a glass substrate to form a thin liquid film. The drying rate of the solvent was measured by a gravimetric technique, and the phase-separated structure in the film was observed by optical microscopy. The results indicated that cellular structures of droplet arrays were formed in the phases evolved primarily during the early stage of drying, and the droplets then coalesced in the intermediate stage to form bigger droplets. The size of the first evolved phase decreased with increasing time at a high drying rate, whereas larger droplets were obtained with longer high drying rate regimes. These results suggested that the droplets were induced by secondary phase separation which was strongly affected by the drying rate of the solvent. 相似文献