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141.
Takafumi Kinuta Yuko Kise Kensaku Kamon Nobuo Tajima Tomohiro Sato Reiko Kuroda Yoshio Matsubara Yoshitane Imai 《Tetrahedron letters》2009,50(42):5786-5789
A novel charge-transfer (CT) host system is developed using CT complexes composed of rac-3,3′-dihydroxy-1,1′-bi-2-naphthol and 1,1′-dibenzyl-4,4′-bipyridinium dichloride. This CT host complex has a 1D channel-like cavity in which guest (MeOH and EtOH) molecules can be discharged and adsorbed. The color and DRS of the CT crystals change according to the presence of guest molecules in the host complex. 相似文献
142.
Erica Sogo Siqi Zhou Haruna Haeiwa Reiko Takeda Kazuma Okazaki Marie Sekita Takuya Yamamoto Mikio Yamano Kazuichi Sakamoto 《Molecules (Basel, Switzerland)》2021,26(15)
Amber—the fossilized resin of trees—is rich in terpenoids and rosin acids. The physiological effects, such as antipyretic, sedative, and anti-inflammatory, were used in traditional medicine. This study aims to clarify the physiological effects of amber extract on lipid metabolism in mouse 3T3-L1 cells. Mature adipocytes are used to evaluate the effect of amber extract on lipolysis by measuring the triglyceride content, glucose uptake, glycerol release, and lipolysis-related gene expression. Our results show that the amount of triacylglycerol, which is stored in lipid droplets in mature adipocytes, decreases following 96 h of treatment with different concentrations of amber extract. Amber extract treatment also decreases glucose uptake and increases the release of glycerol from the cells. Moreover, amber extract increases the expression of lipolysis-related genes encoding perilipin and hormone-sensitive lipase (HSL) and promotes the activity of HSL (by increasing HSL phosphorylation). Amber extract treatment also regulates the expression of other adipocytokines in mature adipocytes, such as adiponectin and leptin. Overall, our results indicate that amber extract increases the expression of lipolysis-related genes to induce lipolysis in 3T3-L1 cells, highlighting its potential for treating various obesity-related diseases. 相似文献
143.
Yuuta Tsukamoto Hiroto Oya Takashi Kikuchi Takeshi Yamada Reiko Tanaka 《Tetrahedron》2019,75(9):1149-1156
Two novel chukrasone-type limonoids, named Guianofruits C and D (1 and 2), a guianolide derivative named Guianofruit E (3), and four novel phragmalin–type limonoids named Guianofruits F–I (4–7), were isolated from the fruit oil of Carapa guianensis AUBLET (Meliaceae), a traditional medicine in Brazil and Latin American countries. Their structures were mainly elucidated based on spectroscopic analyses using 1D and 2D NMR techniques. The effects of compounds 1–6 on the production of NO by LPS-activated mouse peritoneal macrophages were investigated. Two new chukrasone-type limonoids, Guianofruits C (1) and D (2), exhibited moderate inhibitory activities. 相似文献
144.
Rose BOUCAUT Takuo NOMURA Kenichiro TAKANO Reiko HIROSHIMA Fuminari ASADA Satoshi OKAHARA Beatriz SANZ-BUSTILLO-AGUIRRE 《Physical Therapy Research》2021,24(2):98
Objective: This study aimed to adapt a pre-existing cross-country comparison (CCC) model to Occupational Health Physiotherapy (OHP) practice as a basis for locating and examining contextual factors that may influence OHP practice in Japan and Australia. Method: A secondary analysis was conducted of existing publicly-available data on OHP and related influential factors, following the five components of the CCC model: work-related legislation; labor market characteristics; culture; physiotherapy practice norms; and organization of OHP practice. Results: Legislation in both countries promotes safe work and rehabilitation of work injured/ill workers. 2019 unemployment was lower in Japan with higher employment protection than Australia. Both countries have an ageing workforce and rising retirement age. Cultural differences relate to higher long-term orientation and uncertainty avoidance in Japan. Australia has higher individualism and physiotherapists are autonomous practitioners with direct access, which differs from Japan. Both countries have a national OHP subgroup, to date only Australia has OHP professional practice standards. Discussion: This study is the first to compare OHP practice in Japan and Australia. Contextual similarities and differences observed may underpin OHP practitioner role and its enhancement in work-related musculoskeletal disorder prevention and management strategies, the return-to-work process, and development of this physiotherapy discipline nationally. Conclusion: Adapting the CCC model to OHP practice enabled a structured exploration of resources and data, from which to extract and compare contextual factors that may shape OHP practice in Japan and Australia. This in turn may provide a useful springboard for further discussion about OHP practice internationally. 相似文献
145.
Tajima K Kato H Rothwell A Akahane-Yamada R Munhall KG 《The Journal of the Acoustical Society of America》2008,123(1):397-413
The present study investigated the extent to which native English listeners' perception of Japanese length contrasts can be modified with perceptual training, and how their performance is affected by factors that influence segment duration, which is a primary correlate of Japanese length contrasts. Listeners were trained in a minimal-pair identification paradigm with feedback, using isolated words contrasting in vowel length, produced at a normal speaking rate. Experiment 1 tested listeners using stimuli varying in speaking rate, presentation context (in isolation versus embedded in carrier sentences), and type of length contrast. Experiment 2 examined whether performance varied by the position of the contrast within the word, and by whether the test talkers were professionally trained or not. Results did not show that trained listeners improved overall performance to a greater extent than untrained control participants. Training improved perception of trained contrast types, generalized to nonprofessional talkers' productions, and improved performance in difficult within-word positions. However, training did not enable listeners to cope with speaking rate variation, and did not generalize to untrained contrast types. These results suggest that perceptual training improves non-native listeners' perception of Japanese length contrasts only to a limited extent. 相似文献
146.
Yanada R Obika S Inokuma T Yanada K Yamashita M Ohta S Takemoto Y 《The Journal of organic chemistry》2005,70(17):6972-6975
We have developed efficient catalytic methods for the stereoselective and diversity synthesis of various (E)-, (Z)-, and disubstituted 3-alkylideneoxindoles and 3-alkylidenebenzofuran-2-ones via palladium-catalyzed Heck/Suzuki-Miyaura, Heck/Heck, and Heck/carbonylation/Suzuki-Miyaura domino reactions. 相似文献
147.
A simple and sensitive method for the determination of isophorone in food samples was developed by headspace solid-phase microextraction (HS-SPME) coupled with gas chromatography-mass spectrometry (GC-MS). Isophorone was separated within 10 min by GC-MS using a DB-1 capillary column and detected with selective ion monitoring mode. The HS-SPME using a polydimethylsiloxane/divinylbenzene (PDMS/DVB) fiber provided effective sample enrichment, and was carried out by fiber exposition at 60 degrees C for 45 min. The extracted isophorone was easily desorbed by fiber exposition in the injection port of a capillary GC-MS system, and carryover was not observed. Using this method, the calibration curve of isophorone was linear in the range 20-1000 pg/mL, with a correlation coefficient 0.9996 (n = 18), and the detection limit (S/N = 3) was 0.5 pg/mL. The HS-SPME/GC-MS method showed 25,000-fold higher sensitivity than the direct injection method (1 microL injection). The within-day and between-day precisions (relative standard deviations) at the concentration of 1 ng/mL isophorone were 3.9% and 6.1% (n=5), respectively. This method was successfully applied to the analysis of food samples without interference peaks. The recoveries of isophorone spiked into food sample were above 84% for a 50 or 500 pg/mL spiking concentration. The analytical results of the contents of isophorone in various food samples were presented. 相似文献
148.
Kouhei Ookuma Tomoyuki Amako Hiyori Aoyama Tomohiro Sato Nobuo Tajima Reiko Kuroda 《Molecular Crystals and Liquid Crystals》2014,592(1):209-217
Charge-transfer (CT) complexes were prepared using racemic (rac)-10,10′-dihydroxy-9,9′-biphenanthryl, which has a large and highly π-conjugated phenanthrene ring, as the electron donor and p-benzoquinone as the electron acceptor. This CT system showed a polymorphism. 相似文献
149.
A structurally diverse array of polynuclear complexes has been identified and structurally characterized from the reaction of 6-methylpyridine-2-methanol (1) with a range of cobalt(II) salts under a variety of reaction conditions. A tetranuclear cubane, [Co4(1-H)4Cl4(H2O)3(CH3OH)], was isolated from the reaction of 1 with CoCl2.6H2O and NaOH in MeOH, and a tetranuclear double cubane, [Co4(1-H)6(NO3)2], was isolated from the reaction of 1 with Co(NO3)2.6H2O and NEt3 in MeOH. A bowl-shaped trinuclear complex, [Co3(1-H)3Cl3(dmso)], which features a triply bridging dmso ligand, assembled upon mixing 1 and CoCl2.6H2O in dmso. A 1-D coordination polymer, [Co(1)2(SO4)](infinity), where the sulfate ligands bridge "[Co(1)2]" units in a mu2:eta1 fashion to build up the polymer structure, was isolated from the reaction of 1 with CoSO4.7H2O. The reaction of the structurally related ligand 8-hydroxyquinaldine (2) with a mixture of CoCl2.6H2O and Co(OAc)2.4H2O lead to the formation of the tetranuclear double cubane, [Co4(2-H)6Cl2]. Temperature-dependent magnetic measurements have also been performed for these five complexes along with the hydrogen-bonded helicate [Co2(1)2(1-H)2]. The hydrogen bonds of the helicate mediate antiferromagnetic interactions between the cobalt(II) centers (J = -3.18(9) cm(-1), g = 2.25(2)). The sulfate bridging ligands of [Co(1)2(SO4)](infinity) are poor mediators of magnetic exchange. The Co(II) centers in the double-cubane complexes [Co4(1-H)6(NO3)2] and [Co4(2-H)6Cl2] are strongly antiferromagnetically coupled to each other at low temperature to give an S = 0 ground state. [Co4(1-H)4Cl4(H2O)3(MeOH)] exhibits rather complicated magnetic behavior; however, we did not observe any evidence for single-molecule magnetism as was seen for structurally related complexes. 相似文献
150.
Wada R Shibuguchi T Makino S Oisaki K Kanai M Shibasaki M 《Journal of the American Chemical Society》2006,128(23):7687-7691
A general catalytic allylation of simple ketoimines was developed using 1 mol % of CuF.3PPh(3) as catalyst, 1.5 mol % of La(O(i)Pr)(3) as the cocatalyst, and stable and nontoxic allylboronic acid pinacol ester as the nucleophile. This reaction constituted a good template for developing the first catalytic enantioselective allylation of ketoimines. In this case, using LiO(i)Pr as the cocatalyst produced higher enantioselectivity and reactivity than La(O(i)Pr)(3). Thus, using the CuF-cyclopentyl-DuPHOS complex (10 mol %) and LiO(i)Pr (30 mol %) in the presence of (t)BuOH (1 equiv) produced high enantioselectivity up to 93% ee from a range of aromatic ketoimines. Mechanistic studies indicated that LiO(i)Pr accelerates the reaction by increasing the concentration of an active nucleophile, allylcopper. 相似文献