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31.
Naonobu Tanaka Yuyu Jia Kanji Niwa Kiyoshi Imabayashi Yutaka Tatano Hideki Yagi Yoshiki Kashiwada 《Tetrahedron》2018,74(1):117-123
Seven new phloroglucinol derivatives, myrtucommunins A–D (1–4), 6-methylisomyrtucommulone B (5), 4-methylmyrtucommulone B (6), and 2-isobutyryl-4-methylphloroglucinol 1-O-β-d-glucopyranoside (7), and one new chromone derivative, undulatoside A 6′-O-gallate (8), were isolated from the leaves of Myrtus communis (Myrtaceae). Myrtucommunins A–D (1–4) were conjugates of polymethylated acylphloroglucinol and flavonol rhamnoside. The absolute configurations of the rhamnosyl moieties for 1–4 were confirmed to be l in each case by HPLC analyses, while those of the aglycones were assigned by comparisons of the experimental and TDDFT calculated ECD spectra. 6-Methylisomyrtucommulone B (5) and 4-methylmyrtucommulone B (6) were assigned as 6/6/6 tricyclic acylphloroglucinol derivatives with a racemic nature. Antimicrobial activities of 1–8 and related known compounds were evaluated. 相似文献
32.
Thermo‐triggered Release of CRISPR‐Cas9 System by Lipid‐Encapsulated Gold Nanoparticles for Tumor Therapy 下载免费PDF全文
Dr. Peng Wang Dr. Lingmin Zhang Prof. Wenfu Zheng Dr. Liman Cong Zhaorong Guo Yangzhouyun Xie Le Wang Rongbing Tang Qiang Feng Prof. Yoh Hamada Prof. Kohsuke Gonda Prof. Zhijian Hu Prof. Xiaochun Wu Prof. Xingyu Jiang 《Angewandte Chemie (International ed. in English)》2018,57(6):1491-1496
CRISPR/Cas9 system is a powerful toolbox for gene editing. However, the low delivery efficiency is still a big hurdle impeding its applications. Herein, we report a strategy to deliver Cas9‐sgPlk‐1 plasmids (CP) by a multifunctional vehicle for tumor therapy. We condensed CPs on TAT peptide‐modified Au nanoparticles (AuNPs/CP, ACP) via electrostatic interactions, and coated lipids (DOTAP, DOPE, cholesterol, PEG2000‐DSPE) on the ACP to form lipid‐encapsulated, AuNPs‐condensed CP (LACP). LACP can enter tumor cells and release CP into the cytosol by laser‐triggered thermo‐effects of the AuNPs; the CP can enter nuclei by TAT guidance, enabling effective knock‐outs of target gene (Plk‐1) of tumor (melanoma) and inhibition of the tumor both in vitro and in vivo. This AuNPs‐condensed, lipid‐encapsulated, and laser‐controlled delivery system provides a versatile method for high efficiency CRISPR/Cas9 delivery and targeted gene editing for treatment of a wide spectrum of diseases. 相似文献
33.
Amino and other functional groups were introduced to a polyethylene substrate starting from the unsaturated pendant and bridge
groups (collectively called side chains) of polyethylene, which had been prepared by γ-ray irradiation under an atmosphere
of 1,3-butadiene of the polyethylene substrate (the drawn film of ultra-high- molecular-weight polyethylene, Mˉv: 5 × 106). 2-Aminoethylamino groups were introduced to the side chains through treatment either with bromine or with peracetic acid
vapor followed by immersion in ethylenediamine. Introduction of amino groups were confirmed by Fourier transform IR spectrometry,
ninhydrin test, and acid–base titration. Starting from 2-aminoethylaminated polyethylene, modification cycles to grow a dendrimer
on the film were applied; these consisted of 2-methoxycarbonylethylation and 2-aminoethylamidation. This technique resulted
in hyperbranched modification of the polymer. The product is a kind of dendrimer grown on the surface of polyethylene film
with amplified amino ends and has anion-exchange capacity and absorbs acid dye. Its application in practical uses is discussed.
Received: 31 March 2000 Accepted: 2 January 2001 相似文献
34.
35.
Nakano K Kawata S Yoneda K Fuyuhiro A Yagi T Nasu S Morimoto S Kaizaki S 《Chemical communications (Cambridge, England)》2004,(24):2892-2893
The variable temperature magnetic susceptibility, X-ray crystallography, and IR and Raman spectra of a new dinuclear complex [{Fe(II)(NCBH(3))(4-phpy)}(2) mu-bpypz)(2)] demonstrated the first two-step spin-crossover associated with a 1 : 1 mixture of high-spin pair [HS-HS] and low-spin pair [LS-LS] at the plateau. 相似文献
36.
K. Yagi N. Sato Y. Sato K. Tamakawa D. Minkov T. Shoji 《Applied Physics A: Materials Science & Processing》2003,77(3-4):461-468
A new method is developed for detection and evaluation of the depth of surface cracks in conductive materials. The main components of the measurement equipment are a conductive wire and a loop antenna, both of which are located as close as possible to the surface of the investigated material, while the antenna loop is perpendicular to the surface and parallel to the wire. Supplying of electrical potential with microwave frequency f and amplitude |s| to the wire results in spreading of induced current close beneath the surface of the material. The induced current redistributes in the vicinity of surface cracks, and some of the current paths flow along the crack walls. This leads to generation of a time-variable magnetic field mostly within the volume of the crack, which is detected by the loop antenna. A theoretical analysis is presented of the contributions of the different types of generated magnetic fields to the potential drop with amplitude |Us| measured by the antenna. The distribution of the ratio R(dB)=|U|/|Us| is measured for specimens of paramagnetic and ferromagnetic steel which contain three artificial cracks with depths of 0.5 mm, 1 mm, and 2 mm, and frequency f=300 MHz of the supplied electrical potential. It turns out that artificial cracks with a depth of d 0.5 mm, located at distances from x=3 mm to x=15 mm from the wire, can be detected. The largest sensitivity of crack detection is achieved for x4 mm when the long axis of a crack is perpendicular to the wire. The crack response of the measured ratio R is proportional to the crack depth when the loop of the antenna is located above or slightly outside an artificial crack, and at least 4 mm from the wire. This relation could be used for evaluation of the depth of real surface cracks. The notable decrement of the crack response outside the crack can indicate the location of the crack tips on the surface of the specimen. It is shown that a loop antenna with a diameter of 7 mm provides the largest crack response, as well as that the developed method can be applied to both paramagnetic and ferromagnetic materials. An example of the detection of a real crack by an antenna is reported for the first time. PACS 81.70.Ex; 84.40.Ba; 84.32.Ff 相似文献
37.
H. Yagi T. Yanagitani H. Yoshida M. Nakatsuka K. Ueda 《Optics & Laser Technology》2007,39(6):1295-1300
We have fabricated Cr3+ and Nd3+ co-doped YAG (Cr;Nd:YAG) ceramics, and investigated their optical properties and laser characteristics. The Cr;Nd:YAG has two broad absorption bands at around 440 nm (4A2→4T1) and 600 nm (4A2→4T2) respectively, caused by Cr3+ ions. In the case of pumping at 440 nm, the maximum effective lifetime of the Cr;Nd:YAG was 737 μs with a 0.1 at% Cr3+ and 1.0 at% Nd3+ co-doped YAG sample. Cr3+ ions take a role of an effective sensitizer to convert the UV light of flashlamp. For single-shot laser operation, a 10.4 J output energy at 1064 nm was obtained with 0.1 at% Cr3+ and 1.0 at% Nd3+ co-doped YAG ceramic rod with a laser efficiency of 4.9%. The laser efficiency was found to be more than twice that of a 1.0 at % Nd3+:YAG ceramic rod. 相似文献
38.
A. A. Kaminskii M. Sh. Akchurin R. V. Gainutdinov K. Takaichi A. Shirakava H. Yagi T. Yanagitani K. Ueda 《Crystallography Reports》2005,50(5):869-873
The microhardness and fracture toughness of laser nanocrystalline ceramics based on the cubic oxides Y2O3 and Y3Al5O12 are determined experimentally. It is shown by comparative measurements that the fracture toughness and microhardness of Y2O3 ceramics exceed the corresponding parameters of Y2O3 single crystals by factors of 2.5 and 1.3, respectively. The fine morphology of grains and grain boundaries in fractures is investigated. It is ascertained that changes in the mechanical properties of the nanocrystalline ceramics under study are related to both the sizes and structure of grains and the structure of grain boundaries. It is suggested that twinning processes determine the mechanisms of formation of nanocrystalline ceramics. 相似文献
39.
Photochemical nitrosation of phenol in aqueous nitrite solution 总被引:1,自引:0,他引:1
40.