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941.
Hui Dong Qi Zhou Limin Zhang Yang Tian 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(39):14086-14091
A biosensor was created for the simultaneous monitoring of endogenous H2Sn and H2S in mouse brains and exploring their roles in activation of the TRPA1 channel under two types of brain disease models: ischemia and Alzheimer's disease (AD). Based on DFT calculations and electrochemical measurements, two probes, 3,4‐bis((2‐fluoro‐5‐nitrobenzoyl)oxy)‐benzoic acid (MPS‐1) and N‐(4‐(2,5‐dinitrophenoxy) phenyl)‐5‐(1, 2‐dithiolan‐3‐yl)pentanamide (MHS‐1), were synthesized for specific recognition of H2Sn and H2S. Through co‐assembly of the two probes at the mesoporous gold film with good anti‐biofouling ability and electrocatalytic activity, this microsensor showed high selectivity for H2Sn and H2S against potential biological interferences. The biosensor can simultaneously determine the concentration of H2Sn from 0.2 to 50 μm , as well as that of H2S from 0.2 to 40 μm . The expression of TRPA1 protein positively correlated with levels of H2Sn under both ischemia and AD. 相似文献
942.
Jun‐Hua Wei Jing‐Wei Yi Min‐Le Han Bo Li Shan Liu Ya‐Pan Wu Lu‐Fang Ma Dong‐Sheng Li 《化学:亚洲杂志》2019,14(20):3694-3701
Effective detection of organic/inorganic pollutants, such as antibiotics, nitro‐compounds, excessive Fe3+ and MnO4?, is crucial for human health and environmental protection. Here, a new terbium(III)–organic framework, namely [Tb(TATAB)(H2O)]?2H2O ( Tb‐MOF , H3TATAB=4,4′,4′′‐s‐triazine‐1,3,5‐triyltri‐m‐aminobenzoic acid), was assembled and characterized. The Tb‐MOF exhibits a water‐stable 3D bnn framework. Due to the existence of competitive absorption, Tb‐MOF has a high selectivity for detecting Fe3+, MnO4?, 4‐nirophenol and nitroimidazole (ronidazole, metronidazole, dimetridazole, ornidazole) in aqueous through luminescent quenching. The results suggest that Tb‐MOF is a simple and reliable reagent with multiple sensor responses in practical applications. To the best of our knowledge, this work represents the first TbIII‐based MOF as an efficient fluorescent sensor for detecting metal ions, inorganic anions, nitro‐compounds, and antibiotics simultaneously. 相似文献
943.
Feiyan Zhang Yuming Dong Pingping Jiang Guangli Wang Na Zhao Huizhen Zhang Dandan Li Jinze Lyu Yan Wang Ji Li Yongfa Zhu 《化学:亚洲杂志》2019,14(23):4193-4200
Photodeposition has been widely used as a mild and efficient synthetic method to deposit co‐catalysts. It is also worth studying how to synthesize non‐noble metal photocatalysts with uniform dispersion. Different synthetic conditions in photodeposition have a certain influence on particle size distribution and photocatalytic activity. Therefore, we designed experiments to prepare the inexpensive composite photocatalyst Ni(OH)2/g‐C3N4 by photodeposition. The Ni(OH)2 co‐catalysts disperse uniformly with particle sizes of about 10 nm. The photocatalytic hydrogen production rate of Ni(OH)2/g‐C3N4 reached about 19 mmol g?1 h?1, with the Ni(OH)2 deposition amount about 1.57 %. During 16 h stability testing, the rate of hydrogen production did not decrease significantly. The composite catalyst also revealed a good hydrogen production performance under sunlight. The Ni(OH)2 co‐catalyst enhanced the separation ability of photogenerated carriers, which was proved by surface photovoltage and fluorescence analysis. 相似文献
944.
Weifu Dong Piming Ma Shifeng Wang Mingqing Chen Xiaoxia Cai Yong Zhang 《Polymer Degradation and Stability》2013
Poly(β-hydroxybutyrate) (PHB) is a bio-based and biodegradable aliphatic polyester, however its application is limited by some disadvantages such as high price, brittleness, poor processability and low melt-strength due to serious thermal degradation. Partial crosslinking initiated by dicumyl peroxide (DCP) was applied in this work to improve the performance of poly(β-hydroxybutyrate)/poly(d,l-lactic acid) (PHB/PDLLA) blends. The partial crosslinking of the blends and its effect on the properties, morphology, rheology and thermal behavior of the blends were investigated. The tensile strength and impact toughness of the PHB were increased by incorporation of the PDLLA, which were improved further after the partial crosslinking because of an increased compatibility between the PHB and the PDLLA phases. The rheological study revealed that the storage modulus (G′) and complex viscosity (η*) of the blends were increased after addition of the DCP. On the other hand, the crystallization of PHB in the blends was restricted to a certain extent by the formation of partially crosslinked network while its crystal form was not modified. 相似文献
945.
Micro‐RNAs (miRNAs) are small, endogenous, singlestranded, and noncoding RNAs. The miRNAs have been found to perform important functions in many cellular processes, such as development, proliferation, differentiation, and apoptosis. Circulating miRNAs have been proposed as emerging biomarkers in diseases such as cancer, diabetes, and cardiovascular disease including acute myocardial infarction (AMI). In this study, we developed CE with LIF (CE‐LIF) using fluorescence‐labeled DNA probe for determination of low abundance miRNA in cell extracts. The target miRNA is miRNA‐499, a biomarker candidate of AMI with low abundance in biological samples. In order to measure the trace level of miRNA, we optimized the hybridization conditions such as hybridization time, temperature, and buffer solution. The highest fluorescence intensity of the hybridized miRNA‐499 was found when hybridization was conducted at 40°C in 50 mM Tris‐acetate (pH 8.0) buffer containing 50 mM NaCl, and 10 mM EDTA for 15 min. The hybridized miRNA‐499 was detected in cultured H9c2 cardiomyoblast cells and the analysis of miRNA‐499 was completed within 1 h using CE‐LIF. These results showed the potential of CE for fast, specific, and sensitive high‐throughput analysis of low‐abundance miRNAs in cell extracts, biofluids, and tissues. 相似文献
946.
Zhao‐Hui Yan Zhu‐Zhen Han Xian‐Qing Hu Qing‐Xin Liu Wei‐Dong Zhang Run‐Hui Liu Hui‐Liang Li 《Helvetica chimica acta》2013,96(1):85-92
Two new sesquiterpenes, 1 and 2 , as well as the five known compounds 3 – 7 , were isolated from the stems of Euonymus alatus. Compounds 2 – 7 have a β‐dihydroagarofuran skeleton. The structures of these compounds were elucidated mainly by spectroscopic methods (1D‐, 2D‐NMR, ESI‐MS, and HR‐ESI‐MS). We also report the X‐ray crystal structure of evonine ( 3 ) for the first time. 相似文献
947.
Cong‐Mei Cao Yi‐Bing Wu Rui‐Xia Guo Mei Dong Françoise Sauriol Chang‐Hong Huo Qing‐Wen Shi Teiko Yamada Hiromasa Kiyota Yu‐Cheng Gu Bin Cong 《Helvetica chimica acta》2013,96(3):375-378
Torreyanoxane, a novel 3,4‐secoglutinane triterpenoid, was isolated from the pulp of Torreya nucifera. The structure was determined on the basis of spectroscopic methods. 相似文献
948.
Seung Young Lee Kyeong Wan Woo Chung Sub Kim Dong Ung Lee Kang Ro Lee 《Helvetica chimica acta》2013,96(2):320-325
Three new furofuran lignans, (+)‐4,4′‐O‐diangeloylpinoresinol ( 1 ), (+)‐4,4′‐O‐diangeloylmedioresinol ( 2 ), and (+)‐4,4′‐O‐diangeloylsyringaresinol ( 3 ), together with the known compound (+)‐syringaresinol, were isolated from the MeOH extract of Rudbeckia laciniata. The structure elucidation of these compounds were based on 1D‐ and 2D‐NMR, and HR‐ESI‐MS data. The additional structural evidence was obtained from alkaline hydrolysis of the compounds. 相似文献
949.
Zhifang Xi Wei Bie Wei Chen Dong Liu Leen van Ofwegen Peter Proksch Wenhan Lin 《Helvetica chimica acta》2013,96(12):2218-2227
Six new biscembranoids, namely, sarcophytolides G–L ( 1 – 6 , resp.), together with six known analogs, were isolated from a marine soft coral Sarcophyton elegans. The structures of the new compounds were established on the basis of 1D‐ and 2D‐NMR (COSY, HSQC, HMBC, and NOESY) spectroscopic analysis together with the aid of MS, CD, and IR data. The unusual isobiscembranoid sarcophytolide G ( 1 ) was found for the first time in the genus Sarcophyton. 相似文献
950.
Dong‐Jun Yu Jun Hu Yan Huang Hong‐Bin Shen Yong Qi Zhen‐Min Tang Jing‐Yu Yang 《Journal of computational chemistry》2013,34(11):974-985
Understanding the interactions between proteins and ligands is critical for protein function annotations and drug discovery. We report a new sequence‐based template‐free predictor (TargetATPsite) to identify the Adenosine‐5′‐triphosphate (ATP) binding sites with machine‐learning approaches. Two steps are implemented in TargetATPsite: binding residues and pockets predictions, respectively. To predict the binding residues, a novel image sparse representation technique is proposed to encode residue evolution information treated as the input features. An ensemble classifier constructed based on support vector machines (SVM) from multiple random under‐samplings is used as the prediction model, which is effective for dealing with imbalance phenomenon between the positive and negative training samples. Compared with the existing ATP‐specific sequence‐based predictors, TargetATPsite is featured by the second step of possessing the capability of further identifying the binding pockets from the predicted binding residues through a spatial clustering algorithm. Experimental results on three benchmark datasets demonstrate the efficacy of TargetATPsite. © 2013 Wiley Periodicals, Inc. 相似文献