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951.
Ping Yuan Xiaoyu Qi Anping Song Mingyue Ma Xinbei Zhang Chunfeng Lu Mianli Bian Naqi Lian Jianling He Shuguo Zheng Huanhuan Jin 《Journal of cellular and molecular medicine》2021,25(15):7354-7366
Although recent evidence has shown that hepatocyte senescence plays a crucial role in the pathogenesis and development of non-alcoholic fatty liver disease (NAFLD), the mechanism is still not clear. The purpose of this study was to investigate the signal transduction pathways involved in the senescence of hepatocyte, in order to provide a potential strategy for blocking the process of NAFLD. The results confirmed that hepatocyte senescence occurred in HFD-fed Golden hamsters and PA-treated LO2 cells as manifested by increased levels of senescence marker SA-β-gal, p16 and p21, heterochromatin marker H3K9me3, DNA damage marker γ-H2AX and decreased activity of telomerase. Further studies demonstrated that iron overload could promote the senescence of hepatocyte, whereas the overexpression of Yes-associated protein (YAP) could blunt iron overload and alleviate the senescence of hepatocyte. Of importance, depression of lncRNA MAYA (MAYA) reduced iron overload and cellular senescence via promotion of YAP in PA-treated hepatocytes. These effects were further supported by in vivo experiments. In conclusion, these data suggested that inhibition of MAYA could up-regulate YAP, which might repress hepatocyte senescence through modulating iron overload. In addition, these findings provided a promising option for heading off the development of NAFLD by abrogating hepatocyte senescence. 相似文献
952.
953.
Solar Cells: Synergic Interface Optimization with Green Solvent Engineering in Mixed Perovskite Solar Cells (Adv. Energy Mater. 20/2017) 下载免费PDF全文
954.
955.
Synthesis and application of thiol‐functionalized magnetic nanoparticles for studying interactions of epirubicin hydrochloride with bovine serum albumin by fluorescence spectrometry 下载免费PDF全文
Huixia Xiong Quanping Diao Rui Jin Daqian Song Xinghua Wang Ying Sun 《Luminescence》2017,32(2):142-148
A novel method was developed for studying the interaction between epirubicin hydrochloride (EPI) and bovine serum albumin (BSA) by fluorescence spectrometry. Fe3O4 magnetic nanoparticles (MNPs) synthesized and functionalized with thiol group were employed for the immobilization and separation of target BSA in reaction solutions. The concentrations of the non‐immobilized BSA and unbound EPI were obtained separately by fluorescence spectrometry. The binding constants (K a ) and number of binding sites (n ) of EPI with BSA were calculated. In this study, the K a value was 5.05 × 105 L mol?1, suggesting a strong binding of EPI to BSA, and the n value was 1.15. The effects of common metal ions on K a of EPI with BSA were also investigated, and the results showed there was clearly bindings between the metal ions and BSA. The precise binding sites of EPI on BSA were determined as being in site I from the competitive displacement experiments. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
956.
Capturing the photo‐signaling state of a photoreceptor in a steady‐state fashion by binding a transition metal complex 下载免费PDF全文
Pengyun Yu Lei Song Jun Qin Jianping Wang 《Protein science : a publication of the Protein Society》2017,26(11):2249-2256
Binding a small molecule to proteins causes conformational changes, but often to a limited extent. Here, we demonstrate that the interaction of a CO‐releasing molecule (CORM3) with a photoreceptor photoactive yellow protein (PYP) drives large structural changes in the latter. The interaction of CORM3 and a mutant of PYP, Met100Ala, not only trigger the isomerization of its chromophore, p‐coumaric acid, from its anionic trans configuration to a protonated cis configuration, but also increases the content of β‐sheet at the cost of α‐helix and random coil in the secondary structure of the protein. The CORM3 derived Met100Ala is found to highly resemble the signaling state, which is one of the key photo‐intermediates of this photoactive protein, in both protein local conformation and chromophore configuration. The organometallic reagents hold promise as protein engineering tools. This work highlights a novel approach to structurally accessing short lived intermediates of proteins in a steady‐state fashion. 相似文献
957.
958.
Xue Qiang Liang Bing Wang Hui-yun Liu Lei 《Journal of trace elements in medicine and biology》2006,20(2):97-104
An understanding of the dynamic behavior of trace elements leaching from coal mine spoil is important in predicting the groundwater quality. The relationship between trace element concentrations and leaching times, pH values of the media is studied. Column leaching tests conducted in the laboratory showed that there was a close correlation between pH value and trace element concentrations. The longer the leaching time, the higher the trace element concentrations. Different trace elements are differently affected by pH values of leaching media. A numerical model for water flow and trace element transport has been developed based on analyzing the characteristics of migration and transformation of trace elements leached from coal mine spoil. Solutions to the coupled model are accomplished by Eulerian-Lagrangian localized adjoint method. Numerical simulation shows that rainfall intensity determined maximum leaching depth. As rainfall intensity is 3.6ml/s, the outflow concentrations indicate a breakthrough of trace elements beyond the column base, with peak concentration at 90cm depth. And the subsurface pollution range has a trend of increase with time. The model simulations are compared to experimental results of trace element concentrations, with reasonable agreement between them. The analysis and modeling of trace elements suggested that the infiltration of rainwater through the mine spoil might lead to potential groundwater pollution. It provides theoretical evidence for quantitative assessment soil-water quality of trace element transport on environment pollution. 相似文献
959.
Mengyuan Li Yu Yan Xinxin Zhang Yidan Zhang Xiaohan Xu Lei Zhang Liangliang Lu Jie Wang Yazhuo Zhang Qiaoling Song Chenyang Zhao 《Journal of cellular and molecular medicine》2021,25(13):6333
JAK/STAT and NFκB signalling pathways play essential roles in regulating inflammatory responses, which are important pathogenic factors of various serious immune‐related diseases, and function individually or synergistically. To find prodrugs that can treat inflammation, we performed a preliminary high‐throughput screening of 18 840 small molecular compounds and identified scaffold compound L971 which significantly inhibited JAK/STAT and NFκB driven luciferase activities. L971 could inhibit the constitutive and stimuli‐dependent activation of STAT1, STAT3 and IκBα and could significantly down‐regulate the proinflammatory gene expression in mouse peritoneal macrophages stimulated by LPS. Gene expression profiles upon L971 treatment were determined using high‐throughput RNA sequencing, and significant differentially up‐regulated and down‐regulated genes were identified by DESeq analysis. The bioinformatic studies confirmed the anti‐inflammatory effects of L971. Finally, L971 anti‐inflammatory character was further verified in LPS‐induced sepsis shock mouse model in vivo. Taken together, these data indicated that L971 could down‐regulate both JAK/STAT and NFκB signalling activities and has the potential to treat inflammatory diseases such as sepsis shock. 相似文献
960.
Anli Yang Fu Peng Lewei Zhu Xing Li Shunling Ou Zhongying Huang Song Wu Cheng Peng Peng Liu Yanan Kong 《Cell death & disease》2021,12(8)
Melatonin has been reported to have tumor-suppressive effects via comprehensive molecular mechanisms, and long non-coding RNAs (lncRNAs) may participate in this process. However, the mechanism by which melatonin affects the function of lncRNAs in triple-negative breast cancer (TNBC), the most aggressive subtype of breast cancer, is still unknown. Therefore, we aimed to investigate the differentially expressed mRNAs and lncRNAs in melatonin-treated TNBC cells and the interaction mechanisms. Microarray analyses were performed to identify differentially expressed mRNAs and lncRNAs in TNBC cell lines after melatonin treatment. To explore the functions and underlying mechanisms of the mRNAs and lncRNAs candidates, a series of in vitro experiments were conducted, including CCK-8, Transwell, colony formation, luciferase reporter gene, and RNA immunoprecipitation (RIP) assays, and mouse xenograft models were established. We found that after melatonin treatment, FUNDC1 and lnc049808 downregulated in TNBC cell lines. Knockdown of FUNDC1 and lnc049808 inhibited TNBC cell proliferation, invasion, and metastasis. Moreover, lnc049808 and FUNDC1 acted as competing endogenous RNAs (ceRNAs) for binding to miR-101. These findings indicated that melatonin inhibited TNBC progression through the lnc049808-FUNDC1 pathway and melatonin could be used as a potential therapeutic agent for TNBC.Subject terms: Breast cancer, Non-coding RNAs 相似文献