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921.
Yoshihiro Saito∗ Kouichi Miura Yoshikazu Tokuoka Yukishige Kondo Masahiko Abe Takatoshi Sato 《Journal of Dispersion Science and Technology》2013,34(6):567-576
The volatility of synthetic fragrances (benzyl formate, benzyl acetate, benzyl propionate) from pluronic P-85 aqueous solution has been investigated by the dynamic headspace method The experimental results showed that the volatility of a more hydrophobic fragrance was strongly controlled by pluronic P-85. This volatile behavior was explained by the solubilization constants of fragrances between the micelle and bulk phase by semiequilibrium dialysis method. 相似文献
922.
Functional Dynamics of Deuterated β2‐Adrenergic Receptor in Lipid Bilayers Revealed by NMR Spectroscopy 下载免费PDF全文
Dr. Yutaka Kofuku Dr. Takumi Ueda Junya Okude Yutaro Shiraishi Keita Kondo Takuya Mizumura Shiho Suzuki Prof. Dr. Ichio Shimada 《Angewandte Chemie (International ed. in English)》2014,53(49):13376-13379
G‐protein‐coupled receptors (GPCRs) exist in conformational equilibrium between active and inactive states, and the former population determines the efficacy of signaling. However, the conformational equilibrium of GPCRs in lipid bilayers is unknown owing to the low sensitivities of their NMR signals. To increase the signal intensities, a deuteration method was developed for GPCRs expressed in an insect cell/baculovirus expression system. The NMR sensitivities of the methionine methyl resonances from the β2‐adrenergic receptor (β2AR) in lipid bilayers of reconstituted high‐density lipoprotein (rHDL) increased by approximately 5‐fold upon deuteration. NMR analyses revealed that the exchange rates for the conformational equilibrium of β2AR in rHDLs were remarkably different from those measured in detergents. The timescales of GPCR signaling, calculated from the exchange rates, are faster than those of receptor tyrosine kinases and thus enable rapid neurotransmission and sensory perception. 相似文献
923.
Crystal Structure of Metallo DNA Duplex Containing Consecutive Watson–Crick‐like T–HgII–T Base Pairs 下载免费PDF全文
Dr. Jiro Kondo Tom Yamada Chika Hirose Dr. Itaru Okamoto Dr. Yoshiyuki Tanaka Prof. Akira Ono 《Angewandte Chemie (International ed. in English)》2014,53(9):2385-2388
The metallo DNA duplex containing mercury‐mediated T–T base pairs is an attractive biomacromolecular nanomaterial which can be applied to nanodevices such as ion sensors. Reported herein is the first crystal structure of a B‐form DNA duplex containing two consecutive T–HgII–T base pairs. The HgII ion occupies the center between two T residues. The N3‐HgII bond distance is 2.0 Å. The relatively short HgII‐HgII distance (3.3 Å) observed in consecutive T–HgII–T base pairs suggests that the metallophilic attraction could exist between them and may stabilize the B‐form double helix. To support this, the DNA duplex is largely distorted and adopts an unusual nonhelical conformation in the absence of HgII. The structure of the metallo DNA duplex itself and the HgII‐induced structural switching from the nonhelical form to the B‐form provide the basis for structure‐based design of metal‐conjugated nucleic acid nanomaterials. 相似文献
924.
Quantitative Analysis of Location‐ and Sequence‐Dependent Deamination by APOBEC3G Using Real‐Time NMR Spectroscopy 下载免费PDF全文
Dr. Ayako Furukawa Dr. Kenji Sugase Dr. Ryo Morishita Prof. Takashi Nagata Prof. Tsutomu Kodaki Prof. Akifumi Takaori‐Kondo Prof. Akihide Ryo Prof. Masato Katahira 《Angewandte Chemie (International ed. in English)》2014,53(9):2349-2352
The human antiretroviral factor APOBEC3G (A3G) deaminates the newly synthesized minus strand of the human immunodeficiency virus 1 (HIV‐1), which results in the abolition of the infectivity of virus‐infectivity‐factor (Vif)‐deficient HIV‐1 strains. 1 – 6 A unique property of A3G is that it deaminates a CCC hot spot that is located close to the 5′ end more effectively than one that is less close to the 5′ end. However, the mechanism of this process is elusive as it includes nonspecific binding of A3G to DNA and sliding of A3G along the DNA strand. Therefore, this process cannot be analyzed by existing methods using the Michaelis–Menten theory. A new real‐time NMR method has been developed to examine the nonspecific binding and the sliding processes explicitly, and it was applied to the analysis of the deamination by A3G. As a result, the location‐dependent deamination can be explained by a difference in the catalytic rates that depend on the direction of the approach of A3G to the target cytidine. Real‐time NMR experiments also showed that A3G deaminates CCCC tandem hotspots with little redundancy, which suggests that A3G efficiently mutates many CCC hotspots that are scattered throughout the HIV‐1 genome. 相似文献
925.
Yu Yanagihara Akiko Suenaga Hikari Kondo Hiromu Saito 《Journal of Polymer Science.Polymer Physics》2017,55(21):1585-1594
We investigated the structure and deformation behavior of the thermoplastic polyurethane (TPU) spherulite by optical microscopy, tensile testing, Hv light scattering, and small angle X‐ray scattering. The TPU spherulite structure obtained by melt crystallization was coarse consisting of bundle‐like structure containing hard segment (HS) lamellar domain in which the HS domains were stacked and the HS chain direction was perpendicular to the longitudinal axis of the HS domain. By stretching, the spherulite was deformed to ellipsoidal one and the stacked HS lamellar domains were tilted in the stretching direction. The deformed spherulite and the tilted HS domain in the spherulite were recovered to the unstretched state by retraction. The recovery of the structure is ascribed to the characteristic spherulite structure consisting of rubbery soft segment matrix physically cross‐linked with the stacked HS domain. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2017 , 55, 1585–1594 相似文献
926.
927.
The rapid release from a double-compressed tablet containing theophylline with the water-soluble polymer, hydroxypropylmethylcellulose (HPMC) or hydroxypropylmethylcellulose phthalate (HPMCP), used as a wall material can be suppressed by argon plasma-irradiation and changed into the sustained-release system due to a decrease in solubility of the outer layer. It was shown that the release profiles can be varied so as to cause theophylline release at different rates, depending on the set of conditions chosen for tablet manufacture and for plasma operation. 相似文献
928.
Kondo Jun 《Proceedings of the Japan Academy. Series B, Physical and biological sciences》2006,82(9):328-338
The phenomenon of the resistance minimum in dilute magnetic alloys is explained in terms of the s-d interaction which takes account of scattering of the conduction electron off the magnetic impurities in metals. Some of the intermetallic compounds which involve rare earth elements or uranium show a very large electronic specific heat and remain non-magnetic even though they show a Curie-like susceptibility at higher temperatures. These phenomena are also explained based on the s-d interaction model. 相似文献
929.
930.
Makoto Nagase Mineki Toba Hiroyuki Kondo Akio Yasuhara Kiyoshi Hasebe 《Analytical sciences》2003,19(12):1617-1620
A concentrated sulfuric acid dissolution technique and a GC method are described for the estimation of tributyl phosphate, tris(2-chloroethyl) phosphate, tris(chloropropyl) phosphate, tris(1,3-dichloro-2-propyl) phosphate, triphenyl phosphate and tris(butoxyethyl) phosphate in soft polyurethane foam. A soft polyurethane foam sample containing organophosphoric acid triesters was dissolved in concentrated sulfuric acid. The solution was added to water, where only the polyurethane was separated out. The pH of the solution was adjusted, and organophosphoric acid triesters were extracted with toluene. After purification, the compounds were determined by GC. The detection limits of the organophosphoric acid triesters were 0.3 - 0.9 microg g(-1). The recoveries of the organophosphoric acid triesters from a 0.05 g sample of soft polyurethane foam were 80.0 - 90.0%, when the spiked amounts were 0.25 - 1 microg. The compounds were detected from soft polyurethane foam at the level of 0.4 - 23.3 microg g(-1). 相似文献