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131.
Mahadi Hasan Noriko Tarashima Koki Fujikawa Takashi Ohgita Susumu Hama Tamotsu Tanaka 《Science and Technology of Advanced Materials》2016,17(1):554-562
An intelligent shRNA expression device (iRed) contains the minimum essential components needed for shRNA production in cells, and could be a novel tool to regulate target genes. However, general delivery carriers consisting of cationic polymers/lipids could impede function of a newly generated shRNA via electrostatic interaction in the cytoplasm. Recently, we found that faint electric treatment (fET) of cells enhanced delivery of siRNA and functional nucleic acids into the cytoplasm in the absence of delivery carriers. Here, we examined fET of cells stably expressing luciferase in the presence of iRed encoding anti-luciferase shRNA. Transfection of lipofectamine 2000 (LFN)/iRed lipoplexes showed an RNAi effect, but fET-mediated iRed transfection did not, likely because of the endosomal localization of iRed after delivery. However, fET in the presence of lysosomotropic agent chloroquine significantly improved the RNAi effect of iRed/fET to levels that were higher than those for the LFN/iRed lipoplexes. Furthermore, the amount of lipid droplets in adipocytes significantly decreased following fET with iRed against resistin in the presence of chloroquine. Thus, iRed could be a useful tool to regulate target genes following fET-mediated cytoplasmic delivery with endosomal escape devices. 相似文献
132.
Kazuyuki Tsubone Noriko Uchida Hideaki Niwase Keiichi Honda 《Journal of the American Oil Chemists' Society》1989,66(6):829-833
A series of new amphoteric surfactants, sodium salts of 2-(N-alkyl-N-methylamino)ethanephosphates (alkyl: n-dodecyl, n-tetradecyl
and n-hexadecyl) were prepared by reacting alkylbromides with N-methylaminoethanol, followed by addition of phosphoric acid
groups and neutralization with sodium hydroxide. The structures of these compounds were confirmed by spectroscopy and elemental
analysis. Physical properties such as Krafft point, isoelectric point, critical micelle concentration, occupation area of
molecule at surface, foaming power and the effect of pH on surface activity were evaluated. These surfactants were found to
exhibit zwitterionic characteristics in the pH range from approximately 5 to 9 and demonstrated good surface-active properties
over a wide pH range (pH 4~10). Large occupation areas of the molecule at a surface in comparison with sodium dodecyl sulfate
was noted as a characteristic feature of these surfactants. 相似文献
133.
The present study investigated the metabolic fate of dietary TAG and DAG and also their digestion products in the stomach
and small intestine. A diet containing 10% TAG or DAG oil, enriched in 1,3-DAG, was fed to Wistar rats ad libitum for 9 d. After 18 h of fasting, each diet was re-fed ad libitum for 1 h. The weights of the contents of the stomach and small intestine were measured, and the acylglycerol and FFA levels
were analyzed by GC at 0, 1, and 4 h after the 1-h re-feeding. The amounts of re-fed diet ingested and the gastric and small
intestinal content were not different between the two diet groups. In the TAG diet group, the main products were TAG and DAG,
especially 1(3),2-DAG. In addition, 1,3-DAG and 1(3)-MAG were present in the stomach, and the 1,3-DAG levels increased over
time after the re-feeding period. In the DAG diet group, the main products in the stomach were DAG, MAG, FFA, and TAG. There
were significantly greater amounts of 1,3-DAG, 1(3)-MAG, and FFA in the DAG diet group in the stomach compared with the TAG
diet group. The amount of FFA in the stomach relative to the amount of ingested TAG plus DAG in the DAG diet group was higher
than that in the TAG diet group. Acylglycerol and FFA levels were considerably lower in the small intestine than in the stomach.
These results indicate that, in the stomach, where acyl migration might occur, the digestion products were already different
between TAG and DAG oil ingestion, and that DAG might be more readily digested by lingual lipase compared with TAG. Furthermore,
almost all of the dietary lipid was absorbed, irrespective of the structure of the acylglycerol present in the small intestine. 相似文献
134.
Kosuke Sato Akihiro Tsuchiya Tai Oshima Noriko Y. Yamasaki Toshimitsu Morooka 《Journal of Low Temperature Physics》2008,151(1-2):345-350
We report on the performance of two types of SQUID gradiometers developed for the readout of magnetic calorimeters. Our previously
developed low dissipation SQUID gradiometer optimized for low temperature operation has demonstrated the flux noise level
of
under a magnetic field of 2.5 mT and 150 mK. With a cylindrical Au:Er paramagnetic sensor mounted inside the octagonal pickup
washer of the SQUID gradiometer, we succeeded in detecting X-ray signals. However, our achieved energy resolution was 47.2±2.1 eV
at 5.9 keV limited by the high operating temperature of 150 mK and by a magnetic field, small for that temperature, due to
the limited critical current of the field coils. Based on these results, we fabricated new arrays of SQUID gradiometer by
tuning the line width and the number of turns of the field coils and shunt resistance to realize a lower noise level and a
larger magnetic field. Furthermore, arrays of SQUID gradiometer with meander patterned pickup washer was fabricated which
provides a stronger coupling between the paramagnetic sensor and the pickup washer, and a larger magnetic field at the sensor.
相似文献
135.
Kazuko Katsuki Shoji Yoneoka Noriko Mori Masatoshi Hasegawa Yasuhiro Yamamoto Yukichi Yoshino 《Journal of Porous Materials》2008,15(1):35-42
Iron-incorporated zeolites were successfully synthesized at a low temperature such as 80°C by choosing appropriate starting
materials and characterized by inductively coupled plasma atomic emission spectrometry (ICP-AES), wide-angle X-ray diffraction
(XRD), Fourier-transform infrared spectroscopy (FT-IR), and magnetic susceptibility. ICP-AES showed␣that Fe component can
be readily incorporated␣up to a maximum extent of Fe substitution, Fe/(Fe + Al) × 100 = 22.7%. XRD measurements suggested
that the zeolites obtained have a crystal structure of gismondine type. The characterizations identified that the Fe component
present in the products is all incorporated into the zeolite framework. The ammonia and water desorption profiles were compared
for Fe-free and 22.7% Fe-zeolites ion-exchanged for NH4+ by means of TG-MS and DSC. The ammonia desorption peak temperatures considerably shifted toward lower temperatures by the
introduction of Fe, suggesting decreased solid acidity. DSC thermograms of the as-synthesized gismondines revealed that they
do not contain free water (i.e., water not coordinated to cations) in the pores irrespective of the Fe content. The enhanced
catalytic reactivity of the Fe-incorporated gismondines was also confirmed from the decomposition of hydrogen peroxide. An
apparent activation energy of 43 kJ mol−1 was obtained independent of the Fe contents in zeolites. This value was much lower than 70 kJ mol−1 for the same reaction in the homogeneous solution containing iron alum as a reference sample. 相似文献
136.
A series of new amphoteric surfactants, having a quaternary ammonium group and a phosphoric acid group, 2-(N-alkyl-N,N-dimethylammonio)ethyl
hydrogen phosphates (alkyl: dodecyl, tetradecyl, hexadecyl), were prepared by introducing a phosphoric acid group into N-alkyl-N,N-dimethyl-(N-2-hydroxyethyl)
ammoniumiodide, followed by neutralization with sodium hydroxide and removal of inorganic salts. By the evaluation of the
physicochemical properties, it was found that the phosphobetaines behave like “nonionic” surfactant in the zwitterionic region,
having very small CMC values in comparison with sodium 2-(N-alkyl-N-methylamino)ethyl hydrogen phosphates. Additionally, similar
trends were also observed in the experiments from the point of the effect of electrolyte and temperature on CMC, respectively.
It should be considered that the hydrophobicity of the surfactant molecule is increased by the electronic interaction between
the quaternary ammonium group and a phosphoric acid group. On the other hand, the phosphobetaines gave the smaller values
of the occupied area per molecule at the air/water interface than sodium 2-(N-alkyl-N-methylamino)ethyl hydrogen phosphates.
Therefore, it is clear that the phosphobetaines have higher surface-active properties than the amphoteric surfactants. 相似文献
137.
Tatsuya Shimada Yuki Kudoh Takuya Noguchi Tomohiro Kagi Midori Suzuki Mei Tsuchida Hiromu Komatsu Miki Takahashi Yusuke Hirata Atsushi Matsuzawa 《International journal of molecular sciences》2021,22(11)
Receptor-interacting protein kinase 1 (RIPK1) is a key component of the tumor necrosis factor (TNF) receptor signaling complex that regulates both pro- and anti-apoptotic signaling. The reciprocal functions of RIPK1 in TNF signaling are determined by the state of the posttranslational modifications (PTMs) of RIPK1. However, the underlying mechanisms associated with the PTMs of RIPK1 are unclear. In this study, we found that RING finger protein 4 (RNF4), a RING finger E3 ubiquitin ligase, is required for the RIPK1 autophosphorylation and subsequent cell death. It has been reported that RNF4 negatively regulates TNF-α-induced activation of the nuclear factor-κB (NF-κB) through downregulation of transforming growth factor β-activated kinase 1 (TAK1) activity, indicating the possibility that RNF4-mediated TAK1 suppression results in enhanced sensitivity to cell death. However, interestingly, RNF4 was needed to induce RIPK1-mediated cell death even in the absence of TAK1, suggesting that RNF4 can promote RIPK1-mediated cell death without suppressing the TAK1 activity. Thus, these observations reveal the existence of a novel mechanism whereby RNF4 promotes the autophosphorylation of RIPK1, which provides a novel insight into the molecular basis for the PTMs of RIPK1. 相似文献
138.
Satoshi Sakoda Noriko Nakao Ikuya Watanabe 《Journal of materials science. Materials in medicine》2018,29(3):34
The aim was to investigate the effect of machining instruments on machinability of dental ceramics. Four dental ceramics, including two zirconia ceramics were machined by three types (SiC, diamond vitrified, and diamond sintered) of wheels with a hand-piece engine and two types (diamond and carbide) of burs with a high-speed air turbine. The machining conditions used were abrading speeds of 10,000 and 15,000?r.p.m. with abrading force of 100?gf for the hand-piece engine, and a pressure of 200?kPa and a cutting force of 80?gf for the air-turbine hand-piece. The machinability efficiency was evaluated by volume losses after machining the ceramics. A high-abrading speed had high-abrading efficiency (high-volume loss) compared to low-abrading speed in all abrading instruments used. The diamond vitrified wheels demonstrated higher volume loss for two zirconia ceramics than those of SiC and diamond sintered wheels. When the high-speed air-turbine instruments were used, the diamond points showed higher volume losses compared to the carbide burs for one ceramic and two zirconia ceramics with high-mechanical properties. The results of this study indicated that the machinability of dental ceramics depends on the mechanical and physical properties of dental ceramics and machining instruments. 相似文献
139.
140.
High‐resolution OLED display with remarkably low power consumption using blue/yellow tandem structure and RGBY subpixels 下载免费PDF全文
Ryohei Yamaoka Toshiki Sasaki Riho Kataishi Noriko Miyairi Koji Kusunoki Makoto Kaneyasu Hiroyuki Miyake Nobuharu Ohsawa Satoshi Seo Yoshiharu Hirakata Shunpei Yamazaki Koji Ono Takayuki Cho Hidenori Mori 《Journal of the Society for Information Display》2015,23(10):451-456
A top‐emission organic light‐emitting diode (OLED) with a microcavity structure combined with a blue/yellow tandem structure was developed. A high‐resolution active‐matrix OLED display with the world's lowest level of power consumption using the tandem OLED with red, green, blue, and yellow subpixels was fabricated. 相似文献