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971.
Tsunoda T Imura T Kadota M Yamazaki T Yamauchi H Kwon KO Yokoyama S Sakai H Abe M 《Colloids and surfaces. B, Biointerfaces》2001,20(2):155-163
The effects of adsorption of two kinds of proteins on the membrane characteristics of liposomes were examined at pH 7.4 in terms of adsorption amounts of proteins on liposomes, penetrations of proteins into liposomal bilayer membranes, phase transition temperature, microviscosity and permeability of liposomal bilayer membranes, using positively charged lysozyme (LSZ) and negatively charged bovine serum albumin (BSA) as proteins and negatively charged L-alpha-dipalmitoylphosphatidylglycerol (DPPG) liposomes. The saturated adsorption amount of LSZ was 720 g per mol of liposomal DPPG, while that of BSA was 44 g per mol of liposomal DPPG. The penetration of LSZ into DPPG lipid membranes was greater than that of BSA. The microviscosity in the hydrophobic region of liposomal bilayer membranes increased due to adsorption (penetration) of LSZ or BSA, while the permeability of liposomal bilayer membranes increased. The gel-liquid crystalline phase transition temperature of liposomal bilayer membranes was not affected by adsorption of LSZ or BSA, while the DSC peak area (heat of phase transition) decreased with increasing adsorption amount of LSZ or BSA. It is suggested that boundary DPPG makes no contribution to the phase transition and that boundary DPPG and bulk DPPG are in the phase-separated state, thereby increasing the permeability of liposomal bilayer membranes through adsorption of LSZ or BSA. A possible schematic model for the adsorption of LSZ or BSA on DPPG liposomes was proposed. 相似文献
972.
Prof. Hisahiro Sasabe Suguru Araki Shoki Abe Nozomi Ito Kengo Kumada Taito Noda Yoshihito Sukegawa Prof. Daisuke Yokoyama Prof. Junji Kido 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(13):e202104408
The weak stability of a hole-transporter upon approaching the anion state is one of the major bottlenecks for developing long-life organic light-emitting devices (OLEDs). Therefore, in this study, we developed a series of thermally and electrically stable hole-transporters that are end-capped with four dibenzofuran units. These materials exhibit i) high bond dissociation energy (BDE) toward the anion state, ii) a high glass transition temperature (Tg>130 °C), and iii) high triplet energy (ET>2.7 eV), thereby enabling approximately 20 % high external quantum efficiency (EQE) and significantly prolonging the stability of both thermally activated delayed fluorescent (TADF) and phosphorescent OLEDs with an operation lifetime at 50 % (LT50) of 20 000–30 000 h at 1000 cd m−2. In addition, investigating their structure-property relationship revealed that ionization potential (IP), BDE, and Tg are critical prerequisites for the hole-transporter to prolong lifetime in OLEDs. 相似文献
973.
Toshiaki Yokoyama 《The Ramanujan Journal》2017,42(1):157-172
The multivariable Euler transform of a solution of the system of linear ordinary differential equations of Okubo normal form is considered. The Pfaffian system satisfied by the transform is derived. Applications to the Appell hypergeometric functions \(F_{1}\), \(F_{3}\), and the Lauricella hypergeometric function \(F_{D}\) are given. 相似文献
974.
Shinobu Ikeno Masaaki Yokoyama Hiroshi Mikawa 《Molecular Crystals and Liquid Crystals》2013,570(1-2):89-98
Dielectric behavior of nematic liquid crystals of p-methoxybenzylidene-p-n-butylaniline and p-ethoxybenzylidene-p-n-butylaniline have been investigated under DC electric field in relation to their optical behavior. Both dielectric permittivity and transmitted light intensity decrease at a threshold voltage of external DC electric field, and the latter reaches a constant low value at higher field, while dielectric permittivity increases via minimum to approach a constant value at higher field strength of about 2 × 104 V/cm. Such a change of dielectric permittivity under DC electric field is characteristic of nematic and supercooled states, and exhibits large dependence on both temperature and sample thickness. This dielectrical observation is discussed in terms of dielectric anisotropy of the nematic liquids oriented to the field, and the disturbance of molecular orientation due to the dynamic scattering at higher DC electric field. 相似文献
975.
A new simple protocol for the conversion of arylboronic acids to hydroxyarenes was achieved using molecular oxygen in the presence of tetrabutylammonium borohydride under blacklight irradiation (360 nm). A radical chain mechanism in which a superoxide ion (O2−.) plays a key role is proposed. 相似文献
976.
Kayo Horie Naoki Nanashima Yoshihito Yokoyama Haruhiko Yoshioka Jun Watanabe 《Molecules (Basel, Switzerland)》2022,27(12)
Ovarian cancer is the most common cause of gynecological malignancy-related mortality since early-stage disease is difficult to diagnose. Advanced clear cell carcinoma of the ovary (CCCO) has dismal prognosis, and its incidence has been increasing in Japan, emphasizing the need for highly sensitive diagnostic and prognostic CCCO biomarkers. Exosomal microRNAs (miRNAs) secreted by tumor cells are known to play a role in carcinogenesis; however, their involvement in ovarian cancer is unclear. In this study, we performed expression profiling of miRNAs from exosomes released by five cell lines representing different histological types of ovarian cancer. Exosomes isolated from culture media of cancer and normal cells were compared for miRNA composition using human miRNA microarray. We detected 143 exosomal miRNAs, whose expression was ≥1.5-fold higher in ovarian cancer cells than in the control. Among them, 28 miRNAs were upregulated in cells of all histological ovarian cancer types compared to control, and three were upregulated in CCCO cells compared to other types. Functional analyses indicated that miR-21 overexpressed in CCCO cells targeted tumor suppressor genes PTEN, TPM1, PDCD4, and MASP1. The identified miRNAs could represent novel candidate biomarkers to diagnose or monitor progression of ovarian cancer, particularly CCCO. 相似文献
977.
Daisuke Tomida Kiyoshi Kuroda Naruhiro Hoshino Kousuke Suzuki Yuji Kagamitani Toru Ishiguro Tsuguo Fukuda Chiaki Yokoyama 《Journal of Crystal Growth》2010,312(21):3161-3164
The solubility of GaN in supercritical ammonia with ammonium chloride as a mineralizer was measured with a weight-loss method. Temperature-, pressure-, and mineralizer concentration-dependence of the solubility of GaN were investigated. The solubility increased with increase in temperature, and its pressure dependence was very low. The solubility behavior was quite different from the case of using the mineralizer KNH2 as a basic mineralizer. 相似文献
978.
Shun Yokoyama Hideyuki Takahashi Takashi Itoh Kenichi Motomiya Kazuyuki Tohji 《Journal of Physics and Chemistry of Solids》2014
Surface oxides on small (2–5 μm) copper metal particles can be removed by chemical reaction with tris(2,3-dibromopropyl) isocyanurate (TIC) in diethylene glycol mono-n-hexyl ether (DGHE) solution under mild conditions where metal particles are not damaged. Surface oxides convert to copper bromide species and subsequently dissolve into the solvent. It was found that resultant surface species are resistant to re-oxidation due to remaining surface bromides. This finding opens up a possibility to create microclines based on cheap copper nanoparticles. 相似文献
979.
Takao Ikami Takuji Kakigami Kunihisa Baba Hitoshi Hamajima Takahito Jomori Toshinao Usui 《Journal of carbohydrate chemistry》2013,32(3):453-470
Abstract To investigate the biological selectin-ligand interactions, four sulfated 2-O-α-L-fucopyranosyl β-D-galactopyranosides containing 2-branched fatty-alkyl residues in place of ceramide have been systematically synthesized. The target glycolipids were assayed for their ability to block the adhesion of HL-60 cells to immobilized P-, L- and E-selectin. Among them, 2-O-α-L-fucopyranosyl sulfatide, which is anchored with 2-(tetradecyl) hexadecyl residue showed significantly more potency of the blocking adhesion to P- and L-selectins. 相似文献
980.