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1.
《Drug discovery today》2022,27(6):1733-1742
Compounds that exhibit assay interference or undesirable mechanisms of bioactivity are routinely encountered in assays at various stages of drug discovery. We observed that assays for the investigation of thiol-reactive and redox-active compounds have not been collected in a comprehensive review. Here, we review these assays and subject them to experimental optimization to improve their reliability. We demonstrate the usefulness of our assay cascade by assaying a library of bioactive compounds, chemical probes, and a set of approved drugs. These high-throughput assays should complement the array of wet-lab and in silico assays during the initial stages of hit discovery campaigns to pursue only hit compounds with tractable mechanisms of action.  相似文献   
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目的 探讨LincRNA-P21通过靶向miR-17-3p对三阴性乳腺癌(TNBC)细胞迁移和侵袭作用的影响。方法 qPCR检测30例TNBC患者肿瘤组织、癌旁正常组织以及6种乳腺细胞(乳腺正常细胞MCF-10A,乳腺癌细胞MDA-MB-231、MDA-MB-435、MDA-MB-468、BT549、T47D)LincRNA-P21和miR-17-3p的表达。取MDA-MB-231细胞,单独过表达LincRNA-P21(实验设对照组、pcDNA3.1空白组、pcDNA-LincRNA-P21组),抑制miR-17-3p表达(实验设对照组、miR-17-3p空白组、miR-17-3p抑制剂组),过表达LincRNA-P21+抑制miR-17-3p表达(实验设对照组、miR-17-3p抑制剂组和pcDNA-LincRNA-P21+miR-17-3p inhibitor组)。CCK-8法检测MDA-MB-231细胞增殖,集落形成实验检测细胞的集落数量,细胞划痕实验检测细胞的迁移能力,Transwell实验检测细胞侵袭能力。Western blot检测E-cadherin和Vimentin蛋白表达。结果 TNBC患者组织中LincRNA-P21的表达明显低于癌旁组织(0.48±0.03 vs. 1.03±0.06,t=11.714,P<0.01),miR-17-3p的表达显著高于癌旁组织(2.93±0.17 vs. 1.02±0.04,t=15.593,P<0.01)。乳腺癌细胞系中LincRNA-P21表达量明显低于MCF-10A,miR-17-3p表达量高于MCF-10A(P<0.01)。单独过表达LincRNA-P21或抑制miR-17-3p后,MDA-MB-231细胞增殖能力、集落形成数量、迁移和侵袭能力均明显下降。过表达LincRNA-P21的同时抑制miR-17-3p,MDA-MB-231细胞增殖能力、集落形成数量、迁移和侵袭能力出现进一步下降,且上调E-cadherin的表达,抑制Vimentin的表达(P<0.05)。结论 LincRNA-P21通过竞争性结合miR-17-3p来抑制MDA-MB-231细胞增殖、集落形成、迁移和侵袭。  相似文献   
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目的:研究Survivin-shRNA对视网膜母细胞瘤HXO-RB44细胞自噬及凋亡的影响。方法:培养视网膜母细胞瘤HXO-RB44细胞,构建Survivin-shRNA载体。按照处理不同分为Survivin-shRNA组、GFP组和CON组。分别采用流式细胞术检测Survivin-shRNA对HXO-RB44细胞凋亡和细胞周期的影响,应用MTT法检测Survivin-shRNA对HXO-RB44细胞活性的影响,Western blot法检测Survivin-shRNA对HXO-RB44 细胞自噬相关蛋白LC3、p62 与mTOR 表达的影响。结果:流式细胞术结果表明,与Control组和GFP组相比,Survivin-shRNA组细胞凋亡率增加,差异有统计学意义(P<0.05);随着作用时间的延长,S期出现阻滞,48 h阻滞最强,显著高于对照组(P<0.05)。MTT结果发现Survivin-shRNA可抑制HXO-RB44细胞增殖活性,与Control组和GFP组相比,差异有统计学意义(P<0.05);Western blot结果发现,与对照组相比,LC3表达量显著增加(P<0.01);而mTOR表达量降低(P<0.01)。结论:Survivin-shRNA可促进视网膜母细胞瘤HXO-RB44细胞的凋亡和自噬水平,进而特异性杀伤肿瘤细胞。  相似文献   
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AimTo assess the gait and cognitive performances of children with cerebral palsy (CP) during dual tasks (DT) in comparison to typically developing (TD) children.MethodThis prospective, observational, case-control study included 18 children with CP (7 girls, 11 boys; median age 12 [10:13] years and 19 controls (9 girls, 10 boys; median age 12 [10:13y6mo] years). Performances were recorded during a simple walking task, 5 DT (walking + cognitive tasks with increasing cognitive load), and 5 simple cognitive tasks (while sitting). Gait parameters were computed using an optoelectronic system during walking tasks. Six parameters were selected for analysis by a principal component analysis. Cognitive performance was measured for each cognitive task. The dual-task cost (DTC) was calculated for each DT.ResultsGait performance decreased in both groups as DT cognitive load increased (e.g., walking speed normalized by leg length, in simple task: 1.25 [1.15:1.46] s−1 for CP, 1.53 [1.38:1.62] s−1 for TD; DT with highest load: 0.64 [0.53:0.80] s−1 for CP, 0.95 [0.75:1.08] s−1 for TD). The CP group performed significantly worse than TD group in every task (including the simple task), but DTC were similar in both groups. A task effect was found for the majority of the gait parameters.InterpretationThe reduced gait performance induced by DT may generate underestimated difficulties for children with CP in daily-life situations, where DT are common. This should be considered in clinical assessments.  相似文献   
7.
Isopentenylation at A37 (i6A37) of some transfer RNAs (tRNAs) plays a vital role in regulating the efficiency and fidelity of protein synthesis. However, whether insects, which are well known for their highly efficient protein synthesis machinery, employ this regulatory mechanism remains uninvestigated. In the current study, a candidate tRNA isopentenyltransferase (IPT) gene with three alternative splicing isoforms (BmIPT1BmIPT3) was identified in Bombyx mori (silkworm). Only BmIPT1 could complement a yeast mutant lacking tRNA IPT. Phylogenetic analysis showed that silkworm tRNA IPT is conserved in the Lepidoptera. BmIPT was expressed in all B. mori tissues and organs that were investigated, but was expressed at a significantly higher level in silk glands of the fourth instar compared to the first day of the fifth instar. Interestingly, BmIPT was expressed at a significantly higher level in the domesticated silkworm, B. mori, than in wild Bombyx mandarina in multiple tissues and organs. Knock‐down of BmIPT by RNA interference caused severe abnormalities in silk spinning and metamorphosis. Constitutive overexpression of BmIPT1 using a cytoplasmic actin 4 promoter in B. mori raised its messenger RNA level more than sixfold compared with nontransgenic insects and led to significant decreases in the body weight and cocoon shell ratio. Together, these results confirm the first functional tRNA IPT in insects and show that a suitable expression level of tRNA IPT is vital for silk spinning, normal growth, and metamorphosis. Thus, i6A modification at position A37 in tRNA probably plays an important role in B. mori protein synthesis.  相似文献   
8.
Gene silencing using RNA interference (RNAi) has become a widely used genetic technique to study gene function in many organisms. In insects, this technique is often applied through the delivery of dsRNA. In the adult female Aedes aegypti, a main vector of human-infecting arboviruses, efficiency of gene silencing following dsRNA injection varies greatly according to targeted genes. Difficult knockdowns using dsRNA can thus hamper gene function analysis. Here, by analysing silencing of three different genes in female Ae. aegypti (p400, ago2 and E75), we show that gene silencing can indeed be dsRNA sequence dependent but different efficiencies do not correlate with dsRNA length. Our findings suggest that silencing is likely also gene dependent, probably due to gene-specific tissue expression and/or feedback mechanisms. We demonstrate that use of high doses of dsRNA can improve knockdown efficiency, and injection of a transfection reagent along with dsRNA reduces the variability in efficiency between replicates. Finally, we show that gene silencing cannot be achieved using siRNA injection in Ae. aegypti adult females. Overall, this work should help future gene function analyses using RNAi in adult females Ae. aegypti, leading toward a better understanding of physiological and infectious processes.  相似文献   
9.
We introduced a simple technique to eliminate electromagnetic interference between a left ventricular assist device (LVAD) and an implantable cardioverter defibrillator (ICD). A 43-year-old male with heart failure and a reduced ejection fraction who had an ICD presented with decompensated heart failure and received an LVAD as a bridge to transplant. Remote monitoring showed persistent atrial fibrillation causing an inappropriate ICD shock leading to a decision to disable shock therapies. However, an in-office interrogation was unsuccessful due to electromagnetic interference. Patient was instructed to extend his arm above his head on the ipsilateral side of the ICD, thus increasing the distance between LVAD and ICD, eliminating the interaction to allow reprogramming of the device.  相似文献   
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