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971.
Keiichiro Sugimoto Midori Amako Hiroaki Takeuchi Kazuya Nakagawa Morio Yoshimura Yoshiaki Amakura Tomoyuki Fujita Shigeo Takenaka Hiroshi Inui 《Molecules (Basel, Switzerland)》2022,27(1)
Inhibition of fructose absorption may suppress adiposity and adiposity-related diseases caused by fructose ingestion. Eucalyptus leaf extract (ELE) inhibits intestinal fructose absorption (but not glucose absorption); however, its active compound has not yet been identified. Therefore, we evaluated the inhibitory activity of ELE obtained from Eucalyptus globulus using an intestinal fructose permeation assay with the human intestinal epithelial cell line Caco-2. The luminal sides of a cell monolayer model cultured on membrane filters were exposed to fructose with or without the ELE. Cellular fructose permeation was evaluated by measuring the fructose concentration in the medium on the basolateral side. ELE inhibited 65% of fructose absorption at a final concentration of 1 mg/mL. Oenothein B isolated from the ELE strongly inhibited fructose absorption; the inhibition rate was 63% at a final concentration of 5 μg/mL. Oenothein B did not affect glucose absorption. In contrast, the other major constituents (i.e., gallic acid and ellagic acid) showed little fructose-inhibitory activity. To our knowledge, this is the first report that oenothein B in ELE strongly inhibits fructose absorption in vitro. ELE containing oenothein B can prevent and ameliorate obesity and other diseases caused by dietary fructose consumption. 相似文献
972.
Synthesis of Poly(L‐lactide) with One Terminal D‐Glucose Residue and Wettability of Its Film Surface
To develop the new‐type poly(L ‐lactide)‐based biomedical material having a wettable surface, the synthesis of poly(L ‐lactide) with one terminal D ‐glucose residue was investigated. After the hydroxyl group at 1‐C of α‐tetrabenzyl glucose, α‐Glc(Bzl)4, was converted to the corresponding potassium alkoxide by using potassium tert‐butoxide, L ‐lactide (L ‐LA) was polymerized in the presence of α‐Glc(Bzl)4‐OK as an initiator in tetrahydrofuran at room temperature to prepare α‐Glc(Bzl)4‐polyLA. Subsequently, the removal of O‐protecting benzyl groups in the terminal α‐Glc(Bzl)4 residue was carried out by hydrogenolysis with Pd/C to obtain the objective D ‐glucose‐end‐capped polyLA, α‐Glc‐polyLA. The wettability of surface of the α‐Glc‐polyLA material is discussed using the difference of the dynamic contact angle between a α‐Glc‐polyLA/homopolyLA blend film and a film of the polyLA homopolymer. 相似文献
973.
974.
Toshio KITAMURA Daichi INOUE Naoko OKOCHI-WATANABE Naoko KATO Yukiko KOMENO Yang LU Yutaka ENOMOTO Noriko DOKI Tomoyuki UCHIDA Yuki KAGIYAMA Katsuhiro TOGAMI Kimihito C. KAWABATA Reina NAGASE Sayuri HORIKAWA Yasutaka HAYASHI Makoto SAIKA Tomofusa FUKUYAMA Kumi IZAWA Toshihiko OKI Fumio NAKAHARA Jiro KITAURA 《Proceedings of the Japan Academy. Series B, Physical and biological sciences》2014,90(10):389-404
Myeloid malignancies consist of acute myeloid leukemia (AML), myelodysplastic syndromes (MDS) and myeloproliferative neoplasm (MPN). The latter two diseases have preleukemic features and frequently evolve to AML. As with solid tumors, multiple mutations are required for leukemogenesis. A decade ago, these gene alterations were subdivided into two categories: class I mutations stimulating cell growth or inhibiting apoptosis; and class II mutations that hamper differentiation of hematopoietic cells. In mouse models, class I mutations such as the Bcr-Abl fusion kinase induce MPN by themselves and some class II mutations such as Runx1 mutations induce MDS. Combinations of class I and class II mutations induce AML in a variety of mouse models. Thus, it was postulated that hematopoietic cells whose differentiation is blocked by class II mutations would autonomously proliferate with class I mutations leading to the development of leukemia. Recent progress in high-speed sequencing has enabled efficient identification of novel mutations in a variety of molecules including epigenetic factors, splicing factors, signaling molecules and proteins in the cohesin complex; most of these are not categorized as either class I or class II mutations. The functional consequences of these mutations are now being extensively investigated. In this article, we will review the molecular basis of hematological malignancies, focusing on mouse models and the interfaces between these models and clinical findings, and revisit the classical class I/II hypothesis. 相似文献
975.
Anisotropic Dissociation of π–π Stacking and Flipping‐Motion‐Induced Crystal Jumping in Alkylacridones and Their Dicyanomethylene Derivatives
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Dr. Takashi Takeda Prof. Tomoyuki Akutagawa 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(23):7763-7770
Ethylacridone ( 1 b ) and dicyanomethylenated acridones 2 a , b , d showed crystal‐jumping activity upon heating. This is the first example of thermosalient behavior in a simple aromatic ketone and its derivatives. A systematic investigation of the jumping behavior of derivatives with different alkyl chains by variable‐temperature X‐ray crystal‐structure analyses revealed the mechanism of this phenomenon. Anisotropic dissociation of π stacking in a dimer was important for inducing crystal jumping in 1 b , whereas the collective fluctuation/flipping motion of a dicyanomethylene unit induced crystal jumping in 2 . 相似文献
976.
977.
Optical Review - We propose a new prism-based surface-plasmon-resonance microscope (PB-SPRM) with a diffraction grating. Unlike the conventional PB-SPRM, the proposed one is free from distortion... 相似文献
978.
Optical Review - Polarization-maintaining (PM) optical fibers are introduced in fiber optic communication systems and optical fiber sensors to improve their performances. It is known that... 相似文献
979.
980.
Tomoyuki Arakawa 《Mathematische Zeitschrift》2012,270(1-2):559-575
We show that a finitely strongly generated, non-negatively graded vertex algebra is C 2-cofinite if and only if it is lisse in the sense of Beilinson et al. (preprint). This shows that the C 2-cofiniteness is indeed a natural finiteness condition. 相似文献