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Herein, we report a convenient solvent-controlled regioselective esterification to access two types of carboxylate esters without any additive or non-green activation strategy. In this transformation, 2-methyleneaziridines served as an ester reagent, providing two alternative electrophilic carbon centers. Notably, this protocol is suitable for some structure-complicated clinical molecules with a carboxylic acid group, presenting remarkable application potential.

Glioblastoma multiforme (GBM) is the most common and malignant brain tumor, and almost half of the patients carrying EGFR-driven tumor with PTEN deficiency are resistant to EGFR-targeted therapy. EGFR amplification and/or mutation is reported in various epithelial tumors. This series of studies aimed to identify a potent compound against EGFR-driven tumor. We screened a chemical library containing over 600 individual compounds purified from Traditional Chinese Medicine against GBM cells with EGFR amplification and found that cinobufagin, the major active ingredient of Chansu, inhibited the proliferation of EGFR amplified GBM cells and PTEN deficiency enhanced its anti-proliferation effects. Cinobufagin also strongly inhibited the proliferation of carcinoma cell lines with wild-type or mutant EGFR expression. In contrast, the compound only weakly inhibited the proliferation of cancer cells with low or without EGFR expression. Cinobufagin blocked EGFR phosphorylation and its downstream signaling, which additionally induced apoptosis and cytotoxicity in EGFR amplified cancer cells. In vivo, cinobufagin blocked EGFR signaling, inhibited cell proliferation, and elicited apoptosis, thereby suppressing tumor growth in both subcutaneous and intracranial U87MG-EGFR xenograft mouse models and increasing the median survival of nude mice bearing intracranial U87MG-EGFR tumors. Cinobufagin is a potential therapeutic agent for treating malignant glioma and other human cancers expressing EGFR.

ARID1A, a key subunit of the SWI/SNF chromatin remodeling complex, exhibits recurrent mutations in various types of human cancers, including liver cancer. However, the function of ARID1A in the pathogenesis of liver cancer remains controversial. Here, we demonstrate that Arid1a knockout may result in states of different cell differentiation, as indicated by single-cell RNA sequencing (scRNA-seq) analysis. Bulk RNA-seq also revealed that Arid1a deficiency upregulated these genes related to cell stemness and differentiation, but downregulated genes related to the hepatic functions. Furthermore, we confirmed that deficiency of Arid1a increased the expression of hepatic stem/progenitor cell markers, such as Cd133 and Epcam, and enhanced the self-renewal ability of cells. Mechanistic studies revealed that Arid1a loss remodeled the chromatin accessibility of some genes related to liver functions. Thus, Arid1a deficiency might contribute to cancer development by increasing the number of stem/progenitor-like cells through dysregulating the expression of these genes related to cell stemness, differentiation and liver functions.

The analysis of genomic point mutations is one of the research strategies to explore the clonal evolution of tumor cells. At present, clonal evolution of tumor cells is mainly determined by bulk sampling and sequencing of different sections of the tumor. Since this approach analyzes a mixture of different cell types, it may not accurately represent the clonal evolution of specific tumor cell populations and likely miss low frequency mutations, especially when the sequencing depths are not sufficient. To address this issue, we have developed a strategy to analyze genomic point mutations from prostate basal cell carcinoma (BCC) tissues at single-cell resolution. Firstly, we optimized the single-cell whole genome amplification procedure with HepG2 cells. Then the single cells from BCC tissue were captured by a microfluidic chip of Fluidigm and processed for whole-genome amplification. Both分析基因碱基突变是探究肿瘤细胞克隆演化的研究方法之一。目前,常取组织不同区域的群体细胞测序,基于群体水平的基因碱基突变频率等信息绘制出肿瘤的克隆演化过程。但是,该方法易遗失低频突变,并且组织群体细胞类型不单一,不能代表特定细胞群体的克隆演化过程。本研究以前列腺基底细胞癌(prostate basal cell carcinoma, BCC)为例,建立了一种探究肿瘤单细胞的基因碱基突变方法,实现了基于单细胞基因碱基突变分析肿瘤细胞的克隆演化过程。首先通过HepG2细胞优化了单细胞全基因组扩增方法,其次用Fluidigm公司的微流控芯片捕获BCC单细胞进行全基因组扩增,然后通过外显子组测序获得

Dendritic cells (DCs) have crucial roles in immune-related diseases. However, it is difficult to explore DCs because of their rareness and heterogeneity. Although previous studies had been performed to detect the phenotypic characteristics of DC populations, the functional diversity has been ignored. Using a combination of flow cytometry, single-cell quantitative PCR, and bioinformatic analysis, we depicted the DC panorama with not only phenotypic but also functional markers. Functional classification of DCs in mouse lymphoid tissue (spleen) and nonlymphoid tissue (liver) was performed. The results revealed that expression of macrophage scavenger receptor 1 ( MSR1) and C-C motif chemokine receptors ( CCR) 1, CCR2, and CCR4 were elevated in liver DCs, suggesting increased lipid uptake and migration abilities. The enriched expression of costimulatory molecule CD80, TLR9, and TLR adaptor MYD88 in spleen DCs indicated a more-mature phenotype, enhanced pathogen recognition, and T-cell stimulation abilities. Furthermore, we compared DCs in the atherosclerotic mouse models with healthy controls. In addition to the quantitative increase in DCs in the liver and spleen of the apolipoprotein E-knockout ( ApoE-/-) mice, the functional expression patterns of the DCs also changed at the single-cell level. These results promote our understanding of the participation of DCs in inflammatory diseases and have potential applications in DC clinical assessment.-Shi, Q., Zhuang, F., Liu, J.-T., Li, N., Chen, Y.-X., Su, X.-B., Yao, A.-H., Yao, Q.-P., Han, Y., Li, S.-S., Qi, Y.-X., Jiang, Z.-L. Single-cell analyses reveal functional classification of dendritic cells and their potential roles in inflammatory disease.

An efficient one-pot synthesis of pyrrolo[3,4-a]indolizine-1,3-diones has been developed from maleimides, pyridines, and acyl bromides through a [3+2] cyclization–oxidation reaction catalyzed by CuII salt under O2 atmosphere. The advantage of this method is the use of molecular oxygen as the oxidant, in the presence of a catalytic amount of hydrated copper(II) chloride, to accomplish the reaction with broad substrate scope and excellent yields.

An efficient one-pot synthesis of pyrrolo[3,4-a]indolizine-1,3-diones has been developed from maleimides, pyridines, and acyl bromides through a [3+2] cyclization–oxidation reaction catalyzed by CuII salt under O2 atmosphere. The advantage of this method is the use of molecular oxygen as the oxidant, in the presence of a catalytic amount of hydrated copper(II) chloride, to accomplish the reaction with broad substrate scope and excellent yields.

According to emergency grid rule requirements, wind farm should has the ability to stay connected and continue generation under external voltage failure conditions, that is, wind turbines have to keep in connection with grid and own continue power supply. Consequently, the dynamic model of double fed wind turbines, converter model and grid model were established to study the transent chatacters of DFIG. Also, current vector control method oriented by the stator flux was applied in converter control. Based on these, PSCAD was used in building models and simulating. Finally, the results shows that vector control is able to fulfill decoupled active and reactive power control of double fed generators and improve system low voltage ride through ability.

For the variable speed operation of large scale wind turbine, the vibrations become key problem that can not be ignored. In this paper, the active vibration control based on Neural Network PID control strategy was researched. Firstly, PID control algorithm was analyzed. Then, the PID control based on Neural Network was described especially BP Network and its algorithm. In the end, this control method was verified using simulation and prototype test. Keywords-Control; PID; Neural Network; Bladed I.INTRODUCTION The more complicated of controlled system, the higher of people requirements, further, people need control system could adapt to uncertainty, time-varying objects and environment ability. Traditional control method based on exact model can hardly meet the requirements. Control is defined as concept including decision, planning and learning ability. The neural network is paid more and more attention because of these advantages mentioned above. The control diagram of wind turbine is shown in Figure 1.

For the consideration of the existing switching device power level, a converter circuit topology is proposed in this paper, which is accorded with the requirement of highpower direct-drive outer rotor permanent magnet generator. Particularly, a control method based on “non-controlled retification, boost chopper and SPWM inverter circuit” is proposed. Designs of the boost chopper circuit and the control system structure of SPWM inverter are mainly performed, then the block diagrams and control programs of the whole control system are set up. Finally Matlab/Simulink is used to carry on the simulation. The result of simulation showed that this method could meet the requirement of wind power generation system, and the feasibility and accuracy of the method are fully confirmed.