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991.
Chang Su Jin‐Song Gong Jin‐Peng Ye Ji‐Meng He Rui‐Yi Li Min Jiang Yan Geng Yan Zhang Jing‐Hua Chen Zheng‐Hong Xu Jin‐Song Shi 《Macromolecular bioscience》2020,20(9)
Keratin is widely recognized as a high‐quality renewable protein resource for biomedical applications. Despite their extensive existence, keratin resources such as feathers, wool, and hair exhibit high stability and mechanical properties because of their high disulfide bond content. Consequently, keratin extraction is challenging and its application is greatly hindered. In this work, a biological extraction strategy is proposed for the preparation of bioactive keratin and the fabrication of self‐assembled keratin hydrogels (KHs). Based on moderate and controlled hydrolysis by keratinase, keratin with a high molecular weight of approximately 45 and 28 kDa that retain its intrinsic bioactivities is obtained. The keratin products show excellent ability to promote cell growth and migration and are conferred with significant antioxidant ability because of their intrinsically high cysteine content. In addition, without the presence of any cross‐linking agent, the extracted keratin can self‐assemble into injectable hydrogels. The KHs exhibit a porous network structure and 3D culture ability, showing potential in promoting wound healing. This enzyme‐driven keratin extraction strategy opens up a new approach for the preparation of keratin that can self‐assemble into injectable hydrogels for biomedical engineering. 相似文献
992.
正Protein kinases have been recognized as dominant regulators of all aspects of tumor progression, including tumorigenesis,proliferation, invasion, and metastasis [1]. During the activation of protein kinases, the binding of ligands (e.g., epidermal growth factor, transforming growth factor-α, and amphiregulin) can cause dimerization, which promotes the 相似文献
993.
994.
995.
Ultrathin Mn Doped Ni-MOF Nanosheet Array for Highly Capacitive and Stable Asymmetric Supercapacitor
Dengchao Zheng Hao Wen Xun Sun Xin Guan Jie Zhang Wenli Tian Hao Feng Dr. Hongjing Wang Prof. Yadong Yao 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(71):17149-17155
In this study, we demonstrate that an Mn-doped ultrathin Ni-MOF nanosheet array on nickel foam (Mn0.1-Ni-MOF/NF) serves as a highly capacitive and stable supercapacitor positive electrode. The Mn0.1-Ni-MOF/NF shows an areal capacity of 6.48 C cm−2 (specific capacity C: 1178 C g−1) at 2 mA cm−2 in 6.0 m KOH, outperforming most reported MOF-based materials. More importantly, it possesses excellent cycle stability to maintain 80.6 % capacity after 5000 cycles. An asymmetric supercapacitor device utilizing Mn0.1-Ni-MOF/NF as the positive electrode and activated carbon as the negative electrode attains a high energy density of 39.6 Wh kg−1 at 143.8 Wkg−1 power density with a capacitance retention of 83.6 % after 5000 cycles. 相似文献
996.
Zixin Chen Dr. Min Chen Dr. Yunfeng Cheng Prof. Toshiyuki Kowada Dr. Jinghang Xie Dr. Xianchuang Zheng Prof. Jianghong Rao 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(8):3298-3305
The condensation reaction between 6-hydroxy-2-cyanobenzothiazole (CBT) and cysteine has been shown for various applications such as site-specific protein labelling and in vivo cancer imaging. This report further expands the substrate scope of this reaction by varying the substituents on aromatic nitriles and amino thiols and testing their reactivity and ability to form nanoparticles for cell imaging. The structure–activity relationship study leads to the identification of the minimum structural requirement for the macrocyclization and assembly process in forming nanoparticles. One of the scaffolds made of 2-pyrimidinecarbonitrile and cysteine joined by a benzyl linker was applied to design fluorescent probes for imaging caspase-3/7 and β-galactosidase activity in live cells. These results demonstrate the generality of this system for imaging hydrolytic enzymes. 相似文献
997.
998.
Acta Mathematicae Applicatae Sinica, English Series - The generalized estimating equations(GEE) approach is perhaps one of the most widely used methods for longitudinal data analysis. While the GEE... 相似文献
999.
Qing Liu Yibin Liu Hua Zheng Chunmei Li Yi Zhang Qiuyu Zhang 《Journal of polymer science. Part A, Polymer chemistry》2020,58(8):1092-1104
Thermoset polymer elastomers that are capable of autonomous repairability upon physical damage at ambient temperature are highly desirable because of their thermal and environmental resistance, outstanding mechanical toughness and stability. To aim at this goal, we demonstrated that tris(diethylamino)phosphine was initially proven as an efficient catalyst for the aliphatic disulfide exchange at mild condition. By making use of the aliphatic disulfide bond reshuffling and elasticity of polyurethane elastomers, the inherently cross-linked polysulfide-based poly(thiourethane-urethane) elastomers were prepared and exhibited the ability to mend without extrinsic stimuli in the presence of phosphorus catalyst at room temperature after artificially damaged. The self-healing efficiency via the mechanical recovery approach was investigated to be mainly dependent upon the cross-linking density of polysulfide and hard segments chemistry, which in turns determined the molecular chain diffusion and reshuffling that was corroborated by the stress-relaxation study. The thermoset elastomer based on asymmetric diisocynate showed a maximum self-healing efficiency of 85.6% compared to 71.6% for the elastomer with symmetric monomer building blocks. The self-healable polymer was confirmed to be recyclable and reprocessable through a cut-compression processing cycle under a quite mild pressure and temperature thanks to the disulfide bond reshuffling. Meanwhile, the recycled thermoset elastomer well maintained the mechanical properties to its original material. 相似文献
1000.
Li Xiang Yao Dongbao Zhou Junxiang Zhou Xiang Sun Xianbao Wei Bing Li Chengxu Zheng Bin Liang Haojun 《中国科学:化学(英文版)》2020,63(1):92-98
Signal amplification is an important issue in DNA nanotechnology and molecular diagnostics. In this work, we report a strategy for the catalytic self-assembly of spherical nucleic acids(SNAs) programmed by two-layer cascaded DNA circuits through integrating an entropy-driven catalytic network, a catalytic hairpin assembly circuit, and a facile SNA assembly-based reporter system. This integrated system could implement ~100,000-fold signal amplification in the presence of 1 p M of input target.Possessing powerful amplification ability of nucleic acid signal, our strategy should be of great potential in fabricating more robust dynamic networks to be applied for signal transduction, DNA computing, and nucleic acid-based diagnostics. 相似文献