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101.
Noji T Kamidaki C Kawakami K Shen JR Kajino T Fukushima Y Sekitoh T Itoh S 《Langmuir : the ACS journal of surfaces and colloids》2011,27(2):705-713
An oxygen-evolving photosynthetic reaction center complex (PSII) was adsorbed into nanopores in SBA, a mesoporous silica compound. We purified the dimer of PSII complex from a thermophilic cyanobacterium, Thermosynechococcus vulcanus, which grows optimally at 57 °C. The thermally stable PSII dimeric complex has a diameter of 20 nm and a molecular mass of 756 kDa and binds more than 60 chlorophylls. The SBA particles, with average internal pore diameters of 15 nm (SBA(15)) and 23 nm (SBA(23)), adsorbed 4.7 and 15 mg of PSII/g SBA, respectively. Measurement with a confocal laser-scanning microscope indicated the adsorption of PSII to the surface and the inner space of the SBA(23) particles, indicating the adsorption of PSII into the 23 nm silica nanopores. PSII did not bind to the inner pores of SBA(15). PSII bound to SBA(23) showed the high and stable activity of a photosynthetic oxygen-evolving reaction, indicating the light-driven electron transport from water to the quinone molecules added in the outer medium. The PSII-SBA conjugate can be a new material for photosensors and artificial photosynthetic systems. 相似文献
102.
Tsukano C Yokouchi S Girard AL Kuribayashi T Sakamoto S Enomoto T Takemoto Y 《Organic & biomolecular chemistry》2012,10(30):6074-6086
The scope and limitations of the platinum catalyzed 7-endo cyclization of internal alkynyl amides were investigated. Substitution of the alkyne with an aryl group gave better results, presumably because it stabilized the transition state. Applying the reaction to a secondary amide, the caprazamycin core was successfully synthesized from commercially available material in eight steps. 相似文献
103.
The carbazole- and indolone-based porphyrinoids 3 and 4 were synthesized by stepwise transition-metal-catalyzed coupling reactions. Palladium metalation of 4 produced 4Pd, which exhibits near-infrared absorption. 相似文献
104.
Synthesis of the indole skeleton was achieved using a Pd-catalyzed cascade process consisting of isocyanide insertion and benzylic C(sp(3))-H activation. It was found that slow addition of isocyanide is effective for reducing the amount of catalyst needed and Ad(2)P(n)Bu is a good ligand for C(sp(3))-H activation. The construction of the tetracyclic carbazole skeleton was also achieved by a Pd-catalyzed domino reaction incorporating alkyne insertion. 相似文献
105.
Kiyama Akihito Endo Nanami Kawamoto Sennosuke Katsuta Chihiro Oida Kumiko Tanaka Akane Tagawa Yoshiyuki 《显形杂志》2019,22(3):449-457
Journal of Visualization - Realization of a needle-free drug delivery device can solve needle-caused problems. Recently, attention has been given to the use of a focused liquid jet instead of the... 相似文献
106.
Chihiro Tanaka Takuro Kobori Mayuka Tameishi Yoko Urashima Takuya Ito Tokio Obata 《Molecules (Basel, Switzerland)》2021,26(18)
Cancer cells employ programmed cell death ligand-1 (PD-L1), an immune checkpoint protein that binds to programmed cell death-1 (PD-1) and is highly expressed in various cancers, including cervical carcinoma, to abolish T-cell-mediated immunosurveillance. Despite a key role of PD-L1 in various cancer cell types, the regulatory mechanism for PD-L1 expression is largely unknown. Understanding this mechanism could provide a novel strategy for cervical cancer therapy. Here, we investigated the influence of ezrin/radixin/moesin (ERM) family scaffold proteins, crosslinking the actin cytoskeleton and certain plasma membrane proteins, on the expression of PD-L1 in HeLa cells. Our results showed that all proteins were expressed at mRNA and protein levels and that all ERM proteins were highly colocalized with PD-L1 in the plasma membrane. Interestingly, immunoprecipitation assay results demonstrated that PD-L1 interacted with ERM as well as actin cytoskeleton proteins. Furthermore, gene silencing of ezrin, but not radixin and moesin, remarkably decreased the protein expression of PD-L1 without affecting its mRNA expression. In conclusion, ezrin may function as a scaffold protein for PD-L1; regulate PD-L1 protein expression, possibly via post-translational modification in HeLa cells; and serve as a potential therapeutic target for cervical cancer, improving the current immune checkpoint blockade therapy. 相似文献
107.
Inside Cover: Synthesis,Properties, and n‐Type Transistor Characteristics of π‐Conjugated Compounds Having a Carbonyl‐Bridged Thiazole‐Fused Polycyclic System (Chem. Eur. J. 50/2014)
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108.
Chihiro Suetake 《Geometriae Dedicata》1994,51(2):123-131
Let be a translation plane of orderq
3,q an odd prime power, whose kern GF(q). Letl
be the line at infinity of . LetG be a solvable collineation group of in the linear translation complement, which acts transitively onl
, and letH be a maximal normal cyclic subgroup ofG. Then the restriction
ofH onl
acts semiregularly onl
and
{1, 2, 3, 6}, where
is the restriction ofG onl
(ifq –1(mod 3), then
{1, 2}). Ifq {3, 5} and
{1, 2}, then is determined completely, using a computer. 相似文献
109.
M Uchida M Chihiro S Morita H Yamashita K Yamasaki T Kanbe Y Yabuuchi K Nakagawa 《Chemical & pharmaceutical bulletin》1990,38(6):1575-1586
A series of 4-substituted 8-[(2-benzimidazolyl)sulfinylmethyl]-1,2,3,4-tetrahydroquinolin es was synthesized and examined for their (H+ + K+)adenosine triphosphatase (ATPase)-inhibitory and antisecretory activities against histamine-induced gastric acid secretion in rats. Many compounds tested were potent inhibitors of (H+ + K+)ATPase. Most compounds showed antisecretory activity. The antiulcer activity against water-immersion stress-induced gastric ulcer, aspirin-induced gastric ulcer and gastric necrosis induced by hydrochloric acid also were tested in the rat. Some of these compounds, in particular, 4-(N-allyl-N-methylamino)-1-ethyl-8-[(5-fluoro-6-methoxy-2-benzimidazoly l) sulfinylmethyl]-1-ethyl-1,2,3,4-tetrahydroquinoline (XVIIx) were found to have potent activity. The structure-activity relationships are discussed. 相似文献
110.
Stereocontrol in radical reactions of oxime ether anchored to polymer support was studied. Highly diastereoselective solid-phase radical reaction was achieved by using triethylborane and diethylzinc as a radical initiator at low reaction temperature, providing a novel method for the synthesis of the alpha-amino acid derivatives with excellent diastereoselectivities. 相似文献