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951.
Takahiro Matsumoto Seikou Nakamura Souichi Nakashima Masayuki Yoshikawa Katsuyoshi Fujimoto Tomoe Ohta Azumi Morita Rie Yasui Eri Kashiwazaki Hisashi Matsuda 《Bioorganic & medicinal chemistry letters》2013,23(18):5178-5181
The methanolic extract from the dried rhizomes of Curcuma comosa cultivated in Thailand was found to inhibit melanogenesis in theophylline-stimulated murine B16 melanoma 4A5 cells. From the methanolic extract, three new diarylheptanoids, diarylcomosols I–III, were isolated together with 12 known diarylheptanoids. Their chemical structures were elucidated on the basis of chemical and physicochemical evidence. The diarylheptanoids inhibited melanogenesis, and several structural requirements of the active constituents for the inhibition were clarified. In particular, (3R)-1,7-bis(4-hydroxyphenyl)-(6E)-6-hepten-3-ol exhibited stronger inhibitory effect [IC50 = 0.36 μM] without inducing cytotoxicity. The biological effect was much stronger than that of a reference compound, arbutin [IC50 = 174 μM]. We conclude that diarylheptanoid analogs are promising therapeutic agents for the treatment of skin disorders. 相似文献
952.
Chin Piow Wong Jun Deguchi Alfarius Eko Nugroho Toshio Kaneda A. Hamid. A. Hadi Hiroshi Morita 《Bioorganic & medicinal chemistry letters》2013,23(6):1786-1788
In our search for lipid-droplets accumulation (LDA) inhibitors, some ceramicines, a series of limonoids isolated from the barks of Chisocheton ceramicus, were discovered to be active as anti-LDA. Preliminary structure–activity relationships (SAR) of ceramicines as LDA inhibitors based on ceramicines A–L (1–12) and ceramicine B derivatives were described. 相似文献
953.
Takayuki Inoue Masataka Morita Takashi Tojo Kousei Yoshihara Akira Nagashima Ayako Moritomo Mitsuru Ohkubo Hiroshi Miyake 《Bioorganic & medicinal chemistry》2013,21(5):1219-1233
Vascular adhesion protein-1 (VAP-1), an amine oxidase that is also known as a semicarbazide-sensitive amine oxidase (SSAO), is present in particularly high levels in human plasma, and is considered a potential therapeutic target for various inflammatory diseases, including diabetes complications such as macular edema.In our VAP-1 inhibitor program, structural modifications following high-throughput screening (HTS) of our compound library resulted in the discovery that thiazole derivative 10, which includes a guanidine group, shows potent human VAP-1 inhibitory activity (IC50 of 230 nM; rat IC50 of 14 nM). Moreover, compound 10 exhibited significant inhibitory effects on ocular permeability in STZ-induced diabetic rats. 相似文献
954.
Kenta Shirasawa Hiroshi Yakushiji Ryotaro Nishimura Takeshige Morita Shota Jikumaru Hidetoshi Ikegami Atsushi Toyoda Hideki Hirakawa Sachiko Isobe 《The Plant journal : for cell and molecular biology》2020,102(6):1313-1322
Ficus erecta, a wild relative of the common fig (F. carica), is a donor of Ceratocystis canker resistance in fig breeding programmes. Interspecific hybridization followed by recurrent backcrossing is an effective method to transfer the resistance trait from wild to cultivated fig. However, this process is time consuming and labour intensive for trees, especially for gynodioecious plants such as fig. In this study, genome resources were developed for F. erecta to facilitate fig breeding programmes. The genome sequence of F. erecta was determined using single‐molecule real‐time sequencing technology. The resultant assembly spanned 331.6 Mb with 538 contigs and an N50 length of 1.9 Mb, from which 51 806 high‐confidence genes were predicted. Pseudomolecule sequences corresponding to the chromosomes of F. erecta were established with a genetic map based on single nucleotide polymorphisms from double‐digest restriction‐site‐associated DNA sequencing. Subsequent linkage analysis and whole‐genome resequencing identified a candidate gene for the Ceratocystis canker resistance trait. Genome‐wide genotyping analysis enabled the selection of female lines that possessed resistance and effective elimination of the donor genome from the progeny. The genome resources provided in this study will accelerate and enhance disease‐resistance breeding programmes in fig. 相似文献
955.
956.
Kitanaka J Kitanaka N Hall FS Uhl GR Tatsuta T Morita Y Tanaka K Nishiyama N Takemura M 《Neurochemical research》2011,36(10):1824-1833
The effects of the histamine H3 receptor agonists (R)-α-methylhistamine, imetit and immepip on methamphetamine (METH)-induced stereotypical behavior were examined in mice. The
administration of METH (10 mg/kg, i.p.) to male ddY mice induced behaviors including persistent locomotion and stereotypical
behaviors, which were classified into four categories: stereotypical head-bobbing (1.9%), circling (1.7%), sniffing (14.3%),
and biting (82.1%). Pretreatment with (R)-α-methylhistamine (3 and 10 mg/kg, i.p.) significantly decreased stereotypical sniffing, but increased stereotypical biting
induced by METH, in a dose-dependent manner. This effect of (R)-α-methylhistamine on behavior was mimicked by imetit or immepip (brain-penetrating selective histamine H3 receptor agonists; 10 mg/kg, i.p. for each drug). Hypothalamic histamine levels 1 h after METH challenge were significantly
increased in mice pretreated with saline. These increases in histamine levels were significantly decreased by pretreatment
with histamine H3 receptor agonists, effects which would appear to underlie the shift from METH-induced stereotypical sniffing to biting. 相似文献
957.
Wichit S Jittmittraphap A Hidari KI Thaisomboonsuk B Petmitr S Ubol S Aoki C Itonori S Morita K Suzuki T Suzuki Y Jampangern W 《Microbiology and immunology》2011,55(2):135-140
Dengue viruses infect cells by attaching to a surface receptor which remains unknown. The putative receptor molecules of dengue virus type 2 on the surface of mosquito (AP-61) and mammalian (LLC-MK2) cell lines were investigated. The immunochemical detection and structural analysis of carbohydrates demonstrated that the neutral glycosphingolipids, L-3 (GlcNAcβ1-3Manβ1-4Glcβ1-1'Cer) in AP-61 cells, and nLc(4) Cer (Galβ1-4GlcNAcβ1-3Galβ1-4Glcβ1-1'Cer) in LLC-MK2 cells were recognized by the virus. These findings strongly suggest that neutral glycosphingolipids share the key determinant for virus binding and that the β-GlcNAc residue may play an important role in dengue virus binding to the host cell surface. 相似文献
958.
Kawashima A Akihiro H Morita H Fukuoka M Honda K Morita M 《Bioresource technology》2011,102(7):4682-4687
In this study, the effective utilization of lignocellulose residue as an adsorbent was investigated. Japanese cypress wood flour subjected to hydrothermal pretreatment and ball-mill grinding was saccharified with an enzyme. The residual wood flour was carbonized and activated by physical and chemical activation to produce adsorbents for persistent organic pollutant removal. The adsorption properties were investigated by pore analysis using the N2 adsorption/desorption isotherm and adsorption tests for dioxin-like polychlorinated biphenyls in a hexane solution. The obtained adsorbents showed high production yields and adsorption properties for dioxin-like polychlorinated biphenyls. 相似文献
959.
Saito C Uemura T Awai C Tominaga M Ebine K Ito J Ueda T Abe H Morita MT Tasaka M Nakano A 《The Plant journal : for cell and molecular biology》2011,68(1):64-73
The plant vacuole fulfills a variety of functions, and is essential for plant growth and development. We previously identified complex and mobile structures on the continuous vacuolar membrane, which we refer to as 'bulbs'. To ascertain their biological significance and function, we searched for markers associated with bulbs, and mutants that show abnormalities with respect to bulbs. We observed bulb-like structures after expression of non-membranous proteins as well as the functional soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) molecules VAM3 and VTI11. Bulbs are formed in more tissues than previously reported, including flowering organs, suspension culture cells, endodermal cells in the flowering stem, and at very early stages of seed germination. Using existing and newly developed marker lines, we found that the frequency of bulb occurrence is significantly decreased in multiple shoot gravitropism (sgr) mutants, which are known to have a defect in vacuolar membrane properties in endodermal cells. Based on results with new marker lines, which enabled us to observe the process of bulb biogenesis, and analysis of the phenotypes of these mutants, we propose multiple mechanisms for bulb formation, one of which may be that used for formation of transvacuolar strands. 相似文献
960.
Array-based comparative genomic hybridization (aCGH) using bacterial artificial chromosomes (BAC) is a powerful method to analyze DNA copy number aberrations of the entire human genome. In fact, CGH and aCGH have revealed various DNA copy number aberrations in numerous cancer cells and cancer cell lines examined so far. In this report, BAC aCGH was applied to evaluate the stability or instability of cell lines. Established cell lines have greatly contributed to advancements in not only biology but also medical science. However, cell lines have serious problems, such as alteration of biological properties during long-term cultivation. Firstly, we investigated two cancer cell lines, HeLa and Caco-2. HeLa cells, established from a cervical cancer, showed significantly increased DNA copy number alterations with passage time. Caco-2 cells, established from a colon cancer, showed no remarkable differences under various culture conditions. These results indicate that BAC aCGH can be used for the evaluation and validation of genomic stability of cultured cells. Secondly, BAC aCGH was applied to evaluate and validate the genomic stabilities of three patient's mesenchymal stem cells (MSCs), which were already used for their treatments. These three MSCs showed no significant differences in DNA copy number aberrations over their entire chromosomal regions. Therefore, BAC aCGH is highly recommended for use for a quality check of various cells before using them for any kind of biological investigation or clinical application. 相似文献