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91.
Sungmi Park Jeong-Kook Kim Chang Joo Oh Seung Hee Choi Jae-Han Jeon In-Kyu Lee 《Experimental & molecular medicine》2015,47(3):e145
Scoparone, which is a major constituent of Artemisia capillaries, has been identified as an anticoagulant, hypolipidemic, vasorelaxant, anti-oxidant and anti-inflammatory drug, and it is used for the traditional treatment of neonatal jaundice. Therefore, we hypothesized that scoparone could suppress the proliferation of VSMCs by interfering with STAT3 signaling. We found that the proliferation of these cells was significantly attenuated by scoparone in a dose-dependent manner. Scoparone markedly reduced the serum-stimulated accumulation of cells in the S phase and concomitantly increased the proportion of cells in the G0/G1 phase, which was consistent with the reduced expression of cyclin D1, phosphorylated Rb and survivin in the VSMCs. Cell adhesion markers, such as MCP-1 and ICAM-1, were significantly reduced by scoparone. Interestingly, this compound attenuated the increase in cyclin D promoter activity by inhibiting the activities of both the WT and active forms of STAT3. Similarly, the expression of a cell proliferation marker induced by PDGF was decreased by scoparone with no change in the phosphorylation of JAK2 or Src. On the basis of the immunofluorescence staining results, STAT3 proteins phosphorylated by PDGF were predominantly localized to the nucleus and were markedly reduced in the scoparone-treated cells. In summary, scoparone blocks the accumulation of STAT3 transported from the cytosol to the nucleus, leading to the suppression of VSMC proliferation through G1 phase arrest and the inhibition of Rb phosphorylation. This activity occurs independent of the form of STAT3 and upstream of kinases, such as Jak and Src, which are correlated with abnormal vascular remodeling due to the presence of an excess of growth factors following vascular injury. These data provide convincing evidence that scoparone may be a new preventative agent for the treatment of cardiovascular diseases. 相似文献
92.
Jihye Park Dawei Feng Shuai Yuan Prof. Dr. Hong‐Cai Zhou 《Angewandte Chemie (International ed. in English)》2015,54(2):430-435
The controlled generation of singlet oxygen is of great interest owing to its potential applications including industrial wastewater treatment, photochemistry, and photodynamic therapy. Two photochromic metal–organic frameworks, PC‐PCN and SO‐PCN, have been developed. A photochromic reaction has been successfully realized in PC‐PCN while maintaining its single crystallinity. In particular, as a solid‐state material which inherently integrates the photochromic switch and photosensitizer, SO‐PCN has demonstrated reversible control of 1O2 generation. Additionally, SO‐PCN shows catalytic activity towards photooxidation of 1,5‐dihydroxynaphthalene. 相似文献
93.
High‐Contrast Red–Green–Blue Tricolor Fluorescence Switching in Bicomponent Molecular Film 下载免费PDF全文
Hyeong‐Ju Kim Dr. Dong Ryeol Whang Chong Han Lee Prof. Soo Young Park 《Angewandte Chemie (International ed. in English)》2015,54(14):4330-4333
Highly efficient red–green–blue (RGB) tricolor luminescence switching was demonstrated in a bicomponent solid film consisting of (2Z,2′Z)‐2,2′‐(1,4‐phenylene)bis(3‐(4‐butoxyphenyl)acrylonitrile) (DBDCS) and (2Z,2′Z)‐3,3′‐(2,5‐bis(6‐(9H‐carbazol‐9‐yl)hexyloxy)‐1,4‐phenylene)bis(2‐(3,5‐bis(trifluoromethyl)phenyl)acrylonitrile) (m‐BHCDCS). Reversible RGB luminescence switching with a high ratiometric color contrast (λem=594, 527, 458 nm for red, green, and blue, respectively) was realized by different external stimuli such as heat, solvent vapor exposure, and mechanical force. It was shown that Förster resonance energy transfer in the bicomponent mixture could be efficiently switched on and off through supramolecular control. 相似文献
94.
Fused Corrole Dimers Interconvert between Nonaromatic and Aromatic States through Two‐Electron Redox Reactions 下载免费PDF全文
Shota Ooi Dr. Takayuki Tanaka Kyu Hyung Park Sangsu Lee Prof. Dr. Dongho Kim Prof. Dr. Atsuhiro Osuka 《Angewandte Chemie (International ed. in English)》2015,54(10):3107-3111
A singly linked corrole dimer was synthesized by condensation of a dipyrromethane‐1‐carbinol with 1,1,2,2‐tetrapyrroethane. Oxidation of the dimer gave doubly linked corrole dimers 9 and 10 as the first examples of fused corrole dimers involving a meso–meso linkage. Dimers 9 and 10 exhibit characteristic 1H NMR spectra, absorption spectra, excited‐state dynamics, and two‐photon absorption (TPA) values, which indicate the nonaromatic nature of 9 and the aromatic nature of 10 . Interestingly, 9 is fairly stable despite its unusual 2H‐corrole structure, which has been ascribed to the presence of two direct connections between the individual corrole units. 相似文献
95.
Real‐Time Monitoring of Cancer Cell Metabolism and Effects of an Anticancer Agent using 2D In‐Cell NMR Spectroscopy 下载免费PDF全文
Dr. He Wen Yong Jin An Wen Jun Xu Prof. Keon Wook Kang Prof. Sunghyouk Park 《Angewandte Chemie (International ed. in English)》2015,54(18):5374-5377
Altered metabolism is a critical part of cancer cell properties, but real‐time monitoring of metabolomic profiles has been hampered by the lack of a facile method. Here, we propose real‐time metabolomic monitoring of live cancer cells using 13C6‐glucose and heteronuclear two‐dimensional (2D) NMR. The method allowed for metabolomic differentiation between cancer and normal cells on the basis of time‐dependent changes in metabolite concentrations. Cancer cells were found to have large in‐ and out‐flux of pyruvate as well as increased net production of alanine and acetate. The method also enabled evaluation of the metabolic effects of galloflavin whose anticancer effects have been attributed to its specific inhibition of lactate dehydrogenase. Our approach revealed previously unknown functional targets of galloflavin, which were further confirmed at the protein levels. Our method is readily applicable to the study of metabolic alterations in other cellular disease model systems. 相似文献
96.
Back Cover: Cofactor‐Free Light‐Driven Whole‐Cell Cytochrome P450 Catalysis (Angew. Chem. Int. Ed. 3/2015) 下载免费PDF全文
97.
98.
Strong Fluorescent Smart Organogel as a Dual Sensing Material for Volatile Acid and Organic Amine Vapors 下载免费PDF全文
Dr. Pengchong Xue Boqi Yao Panpan Wang Peng Gong Zhenqi Zhang Prof. Ran Lu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(48):17508-17515
An L ‐phenylalanine derivative ( C12PhBPCP ) consisting of a strong emission fluorophore with benzoxazole and cyano groups is designed and synthesized to realize dual responses to volatile acid and organic amine vapors. The photophysical properties and self‐assembly of the said derivative in the gel phase are also studied. C12PhBPCP can gelate organic solvents and self‐assemble into 1 D nanofibers in the gels. UV/Vis absorption spectral results show H‐aggregate formation during gelation, which indicates strong exciton coupling between fluorophores. Both wet gel and xerogel emit strong green fluorescence because the cyano group suppresses fluorescence quenching in the self‐assemblies. Moreover, the xerogel film with strong green fluorescence can be used as a dual chemosensor for quantitative detection of volatile acid and organic amine vapors with fast response times and low detection limits owing to its large surface area and amplified fluorescence quenching. The detection limits are 796 ppt and 25 ppb for gaseous aniline and trifluoroacetic acid (TFA), respectively. 相似文献
99.
Fluorescence Polarization Based Nucleic Acid Testing for Rapid and Cost‐Effective Diagnosis of Infectious Disease 下载免费PDF全文
Dr. Ki Soo Park Prof. Richelle C. Charles Prof. Edward T. Ryan Prof. Ralph Weissleder Prof. Hakho Lee 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(46):16359-16363
A new nucleic acid detection method was developed for a rapid and cost‐effective diagnosis of infectious disease. This approach relies on the three unique elements: 1) detection probes that regulate DNA polymerase activity in response to the complementary target DNA; 2) universal reporters conjugated with a single fluorophore; and 3) fluorescence polarization (FP) detection. As a proof‐of‐concept, the assay was used to detect and sub‐type Salmonella bacteria with sensitivities down to a single bacterium in less than three hours. 相似文献
100.
Ryo Nozawa Keitaro Yamamoto Prof. Dr. Ji‐Young Shin Prof. Dr. Satoru Hiroto Prof. Dr. Hiroshi Shinokubo 《Angewandte Chemie (International ed. in English)》2015,54(29):8454-8457
Treatment of antiaromatic nickel(II) norcorrole with potassium cyanide provided nickel(II) 3‐cyanonorcorrole with perfect regioselectivity without the help of a catalyst. The reaction of the nickel(II) norcorrole with phenol or thiophenol in the presence of a base also yielded substitution products. The antiaromatic 16π conjugation system in the norcorrole core was preserved in the functionalized products. Introduction of phenylthio groups significantly decreased the HOMO–LUMO gap and enhanced the near IR absorption property. 相似文献