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951.
The beneficial effects of icariin in the management of many diseases, such as chronic renal failure and heart failure, are well known. Icariin has also been shown to ameliorate osteoarthritis (OA) symptoms; however, the underlying mechanisms remain unclear. In this study, a bioinformatics analysis was performed to investigate the KEGG pathways of icariin-targeted genes involved in OA. Our study suggests that icariin plays a role in OA by regulating inflammatory cytokine production, insulin resistance, and cell survival through modulation of the NF-κB, MAPK, and Akt signaling pathways. Importantly, IKBKB, NFKBIA, MAPK8, MAPK9, and MAPK10 may be the hub genes affected by icariin when providing its beneficial effects on OA. In addition, we found that icariin decreases proinflammatory factors and inhibits chondrocyte apoptosis through suppression of the NF-κB pathway. Our study highlights a set of KEGG pathways that could explain the molecular mechanism of icariin's action on OA, suggesting that icariin could be considered as a promising therapeutic option for OA.  相似文献   
952.
This study aims to explore the ability of magnetic resonance imaging (MRI) in mucin 1 (MUC1) modified superparamagnetic iron oxide nanoparticle (SPION) targeting human pancreatic cancer (PC). The MUC1 target-directed probe was prepared through MUC1 conjugated to SPION using the chemical method to assess its physiochemical characteristics, including hydration diameter, surface charge, and magnetic resonance signal. The cytotoxicity of MUC1-USPION was verified by MTS assay. BxPC-3 was cultured with MUC1-USPION and SPION in different concentrations. The combined condition of the targeted probes and cells were observed through Prussian blue staining. The nude mice model of pancreatic cancer was established to investigate the application of the probe. MRI was performed to determine the intensity of the signal of the transplanted tumor, while immunohistochemistry and Western blot analysis were performed to detect the expression of MUC1 after taking the transplanted tumor specimen. The particle size of the prepared molecular probe was 63.5 ± 3.2 nm, and the surface charge was 10.2 mV. Furthermore, the probe solution could significantly reduce the MRI at T2, and the magnetic resonance transverse relaxation rate (ΔR2) has a linear relationship with the concentration of iron in the solution. The cell viability of MUC1-USPION in different concentrations revealed no statistical difference, according to the MTS assay. In vitro, the MRI demonstrated decreased T2WI signal intensity in both groups, especially the targeting group. In vivo, MUC1 could selectively accumulate in the nude mice model, and significantly reduce the T2 signal strength. In subsequent experiments, the expression of MUC1 was high in pancreatic cancer tissues, but low in normal pancreatic tissues, as determined by immunohistochemistry and Western blot analysis. The prepared samples can be combined with pancreatic cancer tissue specificity by in vivo imaging, providing reliable early in vivo imaging data for disease diagnosis.  相似文献   
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956.
Objectives: The association of Per3 length polymorphism with susceptibility of Alzheimer Disease (AD) was examined in the present study. Methods: This study was constructed using the case-control method and investigated the association of Per3 length polymorphism with susceptibility of AD. Genotypes of APOE and Per3 length were determined by a PCR restriction fragment length polymorphism detection method. Results: In this study, we gathered 130 unrelated AD patients and 188 controls in performing an analysis the association of Per3 length polymorphism with susceptibility of AD. In the whole sample or APOE ε4 non-carriers, an increased prevalence of five repeat homozygotes of Per3 length in AD patients had significant higher than that in controls (in the whole sample: χ2 = 7.261,= 0.0176; in APOE ε4 non-carriers: χ2 = 6.086, p = 0.030). And, among APOE ε4 carriers, an increased prevalence of five repeat homozygotes of Per3 length in AD patients had also significant higher than that in controls (χ2 = 3.893, p = 0.0319). Conclusions: Among APOE ε4 non-carriers, five repeat homozygotes of Per3 length was associated with a high susceptibility of AD among APOE ε4 carriers and non-carriers.  相似文献   
957.
A series of 1-aryl-5-(4-arylpiperazine-1-carbonyl)-1H-tetrazols as microtubule destabilizers were designed, synthesised and evaluated for anticancer activity. Based on bioisosterism, we introduced the tetrazole moiety containing the hydrogen-bond acceptors as B-ring of XRP44X analogues. The key intermediates ethyl 1-aryl-1H-tetrazole-5-carboxylates 10 can be simply and efficiently prepared via a microwave-assisted continuous operation process. Among the compounds synthesised, compound 6–31 showed noteworthy potency against SGC-7901, A549 and HeLa cell lines. In mechanism studies, compound 6–31 inhibited tubulin polymerisation and disorganised microtubule in SGC-7901 cells by binding to tubulin. Moreover, compound 6–31 arrested SGC-7901cells in G2/M phase. This study provided a new perspective for development of antitumor agents that target tubulin.  相似文献   
958.
生长素输出载体PIN家族研究进展   总被引:1,自引:0,他引:1  
林雨晴  齐艳华 《植物学报》2021,56(2):151-165
生长素极性运输调控植物的生长发育。生长素极性运输主要依赖3类转运蛋白: AUX/LAX、PIN和ABCB蛋白家族。生长素在细胞间流动的方向与PIN蛋白在细胞上的极性定位密切相关。PIN蛋白由1个中心亲水环和2个由中心亲水环隔开的疏水区组成。中心亲水环上含多个磷酸化位点,其为一些蛋白激酶的靶点。PIN蛋白受多方面调控,包...  相似文献   
959.
作为新型的基因组编辑工具,碱基编辑技术结合了CRISPR/Cas系统的定位功能和碱基脱氨酶的编辑功能,可实现特定位点的碱基突变,具有不产生双链DNA断裂,无需外源模板且不依赖染色体DNA同源重组的优势.目前,研究者们已在重要的工业生产菌株谷氨酸棒杆菌(Corynebacterium glutamicum)中开发了多种碱...  相似文献   
960.

Correction to: The EMBO Journal (2021) 40: e107786. DOI 10.15252/embj.2021107786 | Published online 8 June 2021The authors would like to add three references to the paper: Starr et al and Zahradník et al also reported that the Q498H or Q498R mutation has enhanced binding affinity to ACE2; and Liu et al reported on the binding of bat coronavirus to ACE2.Starr et al and Zahradník et al have now been cited in the Discussion section, and the following sentence has been corrected from:“According to our data, the SARS‐CoV‐2 RBD with Q498H increases the binding strength to hACE2 by 5‐fold, suggesting the Q498H mutant is more ready to interact with human receptor than the wildtype and highlighting the necessity for more strict control of virus and virus‐infected animals”.to“Here, according to our data and two recently published papers, the SARS‐CoV‐2 RBD with Q498H or Q498R increases the binding strength to hACE2 (Starr et al, 2020; Zahradník et al, 2021), suggesting the mutant with Q498H or Q498R is more ready to interact with human receptor than the wild type and highlighting the necessity for more strict control of virus and virus‐infected animals”.The Liu et al citation has been added to the following sentence:“In another paper published by our group recently, RaTG13 RBD was found to bind to hACE2 with much lower binding affinity than SARS‐CoV‐2 though RaTG13 displays the highest whole‐genome sequence identity (96.2%) with the SARS‐CoV‐2 (Liu et al, 2021)”.Additionally, the authors have added the GISAID accession IDs to the sequence names of the SARS‐CoV‐2 in two human samples (Discussion section). To make identification unambiguous, the sequence names have been updated from “SA‐lsf‐27 and SA‐lsf‐37” to “GISAID accession ID: EPI_ISL_672581 and EPI_ISL_672589”.Lastly, the authors declare in the Materials and Methods section that all experiments employed SARS‐CoV‐2 pseudovirus in cultured cells. These experiments were performed in a BSL‐2‐level laboratory and approved by Science and Technology Conditions Platform Office, Institute of Microbiology, Chinese Academy of Sciences.These changes are herewith incorporated into the paper.  相似文献   
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