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101.
Covalent Self‐Assembly and One‐Step Photocrosslinking of Tyrosine‐Rich Oligopeptides to Form Diverse Nanostructures 下载免费PDF全文
Dr. Kyoung‐Ik Min Dr. Gyeongwon Yun Dr. Yoonjung Jang Kyung‐Rok Kim Dr. Young Ho Ko Dr. Hyung‐Seok Jang Prof. Dr. Yoon‐Sik Lee Prof. Dr. Kimoon Kim Prof. Dr. Dong‐Pyo Kim 《Angewandte Chemie (International ed. in English)》2016,55(24):6925-6928
We present covalently self‐assembled peptide hollow nanocapsule and peptide lamella. These biomimetic dityrosine peptide nanostructures are synthesized by one‐step photopolymerization of a tyrosine‐rich short peptide without the aid of a template. This simple approach offers direct synthesis of fluorescent peptide nanocages and free‐standing thin films. The simple crosslinked peptide lamella films provide robust mechanical properties with an elastic modulus of approximately 30 GPa and a hardness of 740 MPa. These nanostructures also allow for the design of peptidosomes. The approach taken here represents a rare example of covalent self‐assembly of short peptides into nano‐objects, which may be useful as microcompartments and separation membranes. 相似文献
102.
Sun Hwa Lee Yeom Pyo Lee So Young Kim Min Seop Jeong Min Jung Lee Hye Won Kang Hoon Jae Jeong Dae Won Kim Eun Joung Sohn Sang Ho Jang Yeon Hyang Kim Hyung Joo Kwon Sung-Woo Cho Jinseu Park Won Sik Eum Soo Young Choi 《Experimental & molecular medicine》2008,40(6):629-638
Phosphatase and tensin homologue deleted on chromosome 10 (PTEN) is a tumor suppressor. Although it is well known to have various physiological roles in cancer, its inhibitory effect on inflammation remains poorly understood. In the present study, a human PTEN gene was fused with PEP-1 peptide in a bacterial expression vector to produce a genetic in-frame PEP-1-PTEN fusion protein. The expressed and purified PEP-1-PTEN fusion protein were transduced efficiently into macrophage Raw 264.7 cells in a time- and dose-dependent manner when added exogenously in culture media. Once inside the cells, the transduced PEP-1-PTEN protein was stable for 24 h. Transduced PEP-1-PTEN fusion protein inhibited the LPS-induced cyclooxygenase 2 (COX-2) and iNOS expression levels in a dose-dependent manner. Furthermore, transduced PEP-1-PTEN fusion protein inhibited the activation of NF-κB induced by LPS. These results suggest that the PEP-1-PTEN fusion protein can be used in protein therapy for inflammatory disorders. 相似文献
103.
Jun Zhang Yi-Yu Lin Hao-Chun Liang Ke-Jia Chi Chiang-Mei Chen Sang Pyo Kim Jia-Rui Sun 《中国物理C(英文版)》2021,(6):220-232
We studied the pair production of charged scalar particles of a five-dimensional near extremal Reissner-Nordstr(o)m-Anti de Sitter (RN-AdS5) black hole.The pair... 相似文献
104.
Sungho Ahn Joo Yeon Hong Moo Ki Hong Young Pyo Jang Myung Sook Oh Jee H. Jung Jongki Hong 《Rapid communications in mass spectrometry : RCM》2009,23(19):3158-3166
Sildenafil and its analogues, which are used as illegal additives in several dietary supplements, were isolated by liquid‐liquid extraction and column chromatography and analyzed by fast‐atom bombardment mass spectrometry (FAB‐MS). Structures of sildenafil and its derivatives were elucidated by FAB‐tandem mass spectrometry (MS/MS) with exact mass measurement in the positive‐ion mode. To find structurally diagnostic ions for the sildenafil analogues, authentic sildenafil was preferentially analyzed by high‐energy collision‐induced dissociation (CID)‐MS/MS. The CID‐MS/MS spectra of [M+H]+ precursor ions resulted in the formation of numerous characteristic ions via a series of dissociative processes. The product ions formed by CID provided important information on the modification of the piperazine ring, the phenylsulfonyl group and the pyrazolopyrimidine moiety of sildenafil. By interpreting their MS/MS spectra, the chemical structures of sildenafil analogues isolated from dietary supplements could be elucidated and fragmentation patterns were proposed. To clearly identify the sidenafil derivatives in dietary supplements, some of the derivatives such as acetildenafil, homosildenafil and hydroxyhomosildenafil which are not commercially available were synthesized and compared with their MS/MS spectra. In addition, high‐resolution mass measurements were conducted to obtain the elemental compositions of sildenafil and its analogues. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
105.
Jongmin Kang Seung Pyo Jang Ju Hoon Lee Hong Gyu Lee Youngmee Kim Cheal Kim 《Tetrahedron letters》2010,51(50):6658-6662
New chromogenic anion receptors 2 and 4 utilizing quinoline and nitrophenyl groups as signaling groups were synthesized. In these receptors, amide and amine groups made strong multiple hydrogen interactions with anions. The receptors 2 and 4 bind anions with a selectivity of F− > CN− > and proved to be an efficient naked-eye detector for the fluoride and cyanide ion. 相似文献
106.
Kim JS Shim SH Chae S Han SJ Kang SS Son KH Chang HW Kim HP Bae K 《Chemical & pharmaceutical bulletin》2005,53(6):696-700
A new triterpenoid saponin, together with five known saponins, were isolated from the nonpolar n-hexane fraction of the leaves of Aralia elata. The structure of the new saponin, durupcoside C, was elucidated as hederagenin 3-O-beta-D-glucopyranosyl(1-->3)-beta-D-glucopyranosyl(1-->3)-alpha-L-arabinopyranoside on the basis of spectroscopic analysis. The known saponins were characterized as 3-O-alpha-L-rhamnopyranosyl(1-->2)-alpha-L-arabinopyranosyl hederagenin 28-O-beta-D-xylopyranosyl(1-->6)-beta-D-glucopyranosyl ester, hederagenin 3-O-beta-D-glucopyranosyl(1-->3)-alpha-L-rhamnopyranosyl(1-->2)-alpha-L-arabinopyranoside, oleanolic acid 3-O-beta-D-glucopyranosyl(1-->3)-alpha-L-rhamnopyranosyl(1-->2)-alpha-L-arabinopyranoside, hederagenin 3-O-alpha-L-rhamnopyranosyl(1-->2)-alpha-L-arabinopyranoside (alpha-hederin), and hederagenin 3-O-beta-D-glucopyranosyl(1-->3)-alpha-L-arabinopyranoside (collinsonidin). In addition, two known lipids, Arisaema glyceride 3 and ceramide mixtures were also isolated and characterized. Collinsonidin and two known lipids were isolated for the first time from this plant. 相似文献
107.
Ki-Young Choi Yong-Man Jeon Choon Pyo Hong Haiil Ryu Il-Hwan Suh 《Journal of chemical crystallography》2001,31(4):197-201
The compound [Zn(L2)Cl]ClO4·H2O (1) (L2 = 2,13,-bis(3-hydroxypropyl)-5,16-di-methyl-2,6,13,17-tetraazatricyclo[14,4,01.18,07.12]docosane) has been synthesized and structurally characterized. 1 crystallizes in the monoclinic system, space group P21/c with a = 8.932(2), b = 16.189(2), c = 22.492(4) Å = 95.34(2)° V = 3238.3(11) Å3; and Z = 4. The zinc atom is placed in a highly distorted tetrahedral environment bonding with three nitrogen atoms of the macrocycle and one chlorine atom. 相似文献
108.
109.
We study the Poisson problem with zero boundary datum in a (finite) polyhedral cylinder with a non-convex edge. Applying the Fourier sine series to the equation along the edge and by a corner singularity expansion for the Poisson problem with parameter, we define the edge flux coefficient and the regular part of the solution on the polyhedral cylinder. We present a numerical method for approximating the edge flux coefficient and the regular part and show the stability. We derive an error estimate and give some numerical experiments. 相似文献
110.
We present a new entanglement purification protocol on three copies of a state via two bilateral controlled-NOT operations. We show that one-round successful probability of our protocol is twice as large as that of the protocol by Feng et al. [Phys. Lett. A 271 (2000) 44], [8], and that our method can be applied to the existing best protocol so as to improve the efficiency. 相似文献