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241.
Jae-Hyun Yang Tae-Yang Song Chanhee Jo Jinyoung Park Han-Young Lee Ilang Song Suji Hong Kwan Young Jung Jaehoon Kim Jeung-Whan Han Hong-Duk Youn Eun-Jung Cho 《Experimental & molecular medicine》2016,48(8):e252
Replication-independent incorporation of variant histone H3.3 has a profound impact on chromatin function and numerous cellular processes, including the differentiation of muscle cells. The histone chaperone HIRA and H3.3 have essential roles in MyoD regulation during myoblast differentiation. However, the precise mechanism that determines the onset of H3.3 deposition in response to differentiation signals is unclear. Here we show that HIRA is phosphorylated by Akt kinase, an important signaling modulator in muscle cells. By generating a phosphospecific antibody, we found that a significant amount of HIRA was phosphorylated in myoblasts. The phosphorylation level of HIRA and the occupancy of phosphorylated protein on muscle genes gradually decreased during cellular differentiation. Remarkably, the forced expression of the phosphomimic form of HIRA resulted in reduced H3.3 deposition and suppressed the activation of muscle genes in myotubes. Our data show that HIRA phosphorylation limits the expression of myogenic genes, while the dephosphorylation of HIRA is required for proficient H3.3 deposition and gene activation, demonstrating that the phosphorylation switch is exploited to modulate HIRA/H3.3-mediated muscle gene regulation during myogenesis. 相似文献
242.
Cellulose diacetate (CDA) plasticized with triacetine was blended by melting extrusion with two different kind of elastomeric core–shell impact modifiers: methyl methacrylate (MMA, shell) grafted onto styrene–butadiene–rubber (SBR, core) (MSBR) and MMA (shell) grafted onto butyl acrylate rubber (BAR, core) (MBAR). The different CDA/MSBR and CDA/MBAR blends were characterized by mechanical properties and morphological observation with various impact modifier contents. The highest impact strength was observed in the case of the blend with 5 wt% of MSBR and 3 wt% of MBAR, respectively. The tensile strength and Young’s modulus of CDA blends were decreased with increasing both MSBR and MBAR. According to SEM observation, MBAR was dispersed more effectively in CDA matrix than that of MSBR, thus indicating improved impact strength. 相似文献
243.
Several benzene (or phenylmethane) sulfinate esters were synthesized in 53–98% yields from the corresponding methoxymethyl (MOM) sulfides employing NBS as oxidant. 相似文献
244.
Young‐gi kim Emilie M. Galand Barry C. Thompson John walker Stephen A. Fossey Tracy D. Mccarley 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(7):665-674
Isoregic conjugated polymers composed of thiophene and dialkoxybenzene units were designed to harvest incident light in the mid‐visible energy range (band gap of 2.1 eV). Poly(1,4‐bis(2‐thienyl)‐2,5‐diheptoxybenzene) (PBTB(OC7H15)2) and poly(1,4‐bis(2‐thienyl)‐2,5‐didodecyloxybenzene) (PBTB(OC12H25)2) have shown significant photovoltaic performance as an electron donor when used in tandem with the electron acceptor [6, 6]‐phenyl C61‐butyric acid methyl ester (PCBM) in bulk hetero‐junction photovoltaic devices. Photovoltaic devices incorporating PBTB(OC7H15)2 and PCBM have shown AM1.5 efficiencies of ~0.6% with a short circuit current density of 2.5 mA/cm2, an open circuit voltage of 0.74 V, and a fill factor of 0.32. Incident Photon‐to‐Current Efficiency (IPCE) of the device was found to be ca. 16% at 410 nm. In order to examine the relationship between the molecular structure of the polymers and their electronic energy levels, and to correlate this with photovoltaic performance, optoelectronic and electrochemical results are discussed in relation to the I‐V characteristics of the devices. Additionally, a computer‐aided simulation is used to gain further insight into the effect of polymer structure on the energetic relationships in the bulk heterojunction devices. 相似文献
245.
Oxidation of 1,4-hydroquinones to 1,4-benzoquinones by mercuric oxide or mercuric trifluoroacetate in methanol has recently been described, and required reaction times of 1–12 hours.1 We now report that use of bromomercury(II) species as oxidants under alkaline conditions greatly reduces the reaction time. This oxidation system has recently been used for conversion of aromatic aldehydes into carboxylic acids.2 相似文献
246.
247.
Xudong Yao Craig Bunt Jillian Cornish Siew‐Young Quek Jingyuan Wen 《Biomedical chromatography : BMC》2013,27(2):197-202
The objective of this study was to qualitatively and quantitatively evaluate bovine lactoferrin (bLf) and its stability using a rapid RP‐HPLC method. bLf could be rapidly detected within 20 min and quantitated at levels down to 5 µg/mL, and the equation of linearity was y = 86.10x + 178.31 with the correlation coefficient (r2) 0.9997. Quantitative data obtained in the present study proved the improved RP‐HPLC method to be a sensitive and accurate analytical tool for bLf determination. The proteolytic cleavage of bLf in simulated human gastrointestinal fluids was further analyzed by RP‐HPLC, and found to follow pseudo‐first‐order kinetics. The typical equation obtained by pepsin was log10 [At]/[A0] = ?0.03x (r2 = 0.85), and log10 [At]/[A0] = ?0.01x (r2 = 0.81) for trypsin and chymotrypsin combination. Pepsinolysis of bLf in simulated gastric fluid was relatively fast with the half‐life t1/2 23.1 min. The digestion of bLf in simulated intestinal fluid was slower with about a 3‐fold increase in half‐life (69.3 min). After the complete proteolysis of bLf, small cleaved peptide fragments were fully separated and identified by RP‐HPLC. The proteolytic study indicated that this validated RP‐HPLC was able to evaluate bLf stability though monitoring the derivatization products. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
248.
Cover Picture: Open‐Pore Two‐Dimensional MFI Zeolite Nanosheets for the Fabrication of Hydrocarbon‐Isomer‐Selective Membranes on Porous Polymer Supports (Angew. Chem. Int. Ed. 25/2016)
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Han Zhang Prof. Qiang Xiao Prof. Xianghai Guo Prof. Najun Li Prashant Kumar Neel Rangnekar Mi Young Jeon Prof. Shaeel Al‐Thabaiti Prof. Katabathini Narasimharao Prof. Sulaiman Nasir Basahel Prof. Berna Topuz Frank J. Onorato Prof. Christopher W. Macosko Prof. K. Andre Mkhoyan Prof. Michael Tsapatsis 《Angewandte Chemie (International ed. in English)》2016,55(25):7009-7009
249.
Mediterranean Journal of Mathematics - Using GTW connection, we considered a real hypersurface M in a complex two-plane Grassmannian $${G_{2}({\mathbb{C}}^{m+2})}$$ when the GTW Reeb Lie derivative... 相似文献
250.