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2.
Tumor cell aggregation is critical for cell survival following the loss of extracellular matrix attachment and dissemination. However, the underlying mechanotransduction of clustering solitary tumor cells is poorly understood, especially in non-small cell lung cancers (NSCLC). Here, we examined whether cell surface protrusions played an important role in facilitating the physical contact between floating cells detached from a substrate. We employed poly-2-hydroxyethyl methacrylate-based 3D culture methods to mimic in vivo tumor cell cluster formation. The suprastructural analysis of human NSCLC A549 cell spheroids showed that finger-like protrusions clung together via the actin cytoskeleton. Time-lapse holotomography demonstrated that the finger-like protrusions of free-floating cells in 3D culture displayed exploratory coalescence. Global gene expression analysis demonstrated that the genes in the organic hydroxyl transport were particularly enriched in the A549 cell spheroids. Particularly, the knockdown of the water channel aquaporin 3 gene (AQP3) impaired multicellular aggregate formation in 3D culture through the rearrangement of the actomyosin cytoskeleton. Moreover, the cells with reduced levels of AQP3 decreased their transmigration. Overall, these data indicate that cell detachment-upregulated AQP3 contributes to cell surface protrusions through actomyosin cytoskeleton remodeling, causing the aggressive aggregation of free-floating cells dependent on the property of the substratum and collective metastasis. 相似文献
3.
Angelico Mendy Nervana Metwali Sarah S. Perry Elizabeth A. Chrischilles Kai Wang Peter S. Thorne 《Indoor air》2020,30(1):88-97
Endotoxin exacerbates asthma. We designed the Louisa Environmental Intervention Project (LEIP) and assessed its effectiveness in reducing household endotoxin and improving asthma symptoms in rural Iowa children. Asthmatic school children (N = 104 from 89 homes) of Louisa and Keokuk counties in Iowa (aged 5-14 years) were recruited and block-randomized to receive extensive (education + professional cleaning) or educational interventions. Environmental sampling collection and respiratory survey administration were done at baseline and during three follow-up visits. Mixed-model analyses were used to assess the effect of the intervention on endotoxin levels and asthma symptoms in the main analysis and of endotoxin reduction on asthma symptoms in exploratory analysis. In the extensive intervention group, dust endotoxin load was significantly reduced in post-intervention visits. The extensive compared with the educational intervention was associated with significantly decreased dust endotoxin load in farm homes and less frequent nighttime asthma symptoms. In exploratory analysis, dust endotoxin load reduction from baseline was associated with lower total asthma symptoms score (Odds ratio: 0.52, 95% confidence interval: 0.29-0.92). In conclusion, the LEIP intervention reduced household dust endotoxin and improved asthma symptoms. However, endotoxin reductions were not sustained post-intervention by residents. 相似文献
4.
Ming-Puu Chen Asta Y. Z. Lord Yu-Yao Cheng Ku-Chou Tai Wen-Harn Pan 《Journal of Computer Assisted Learning》2020,36(3):383-396
Reflective judgement is crucial for medical-related practitioners in dealing with controversial issues. However, the conformity phenomenon is likely to occur and interfere with reflective judgement learning during interactive activities. Effective strategies are required to moderate the conformity behaviour tendency (CBT) and improve reflective judgement performance (RJP). This study demonstrates two significant results: (a) Compared with the guided self-reflection learning strategy, the online collective reflection (OCR) learning strategy effectively weakened the learners' general CBT while dealing with professional controversial issues; and (b) a significantly negative correlation between the RJP achieved and the change of CBT in online environment was detected in the OCR group. The implications and potential applications in higher education were discussed. Further studies are needed to confirm the long-term effects and the extending application to other professional studies. 相似文献
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针对新桥煤矿2301综采工作面机载喷雾系统喷雾效果差、喷雾耗水量大造成煤质含水量超标、喷嘴雾化程度不高、喷嘴容易发生堵塞等问题,提出了高压喷雾系统设计方案,选择了1.2mm的锥形引射喷嘴和1.5mm的扇形引射喷嘴。采用固定水泵供水方式,结合工作面实际情况,计算出喷雾总用水量247.5L/min,提高了喷雾射程,提升了除尘效果。 相似文献
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根据某面板堆石坝施工期、蓄水初期以及几年来的沉降观测资料,对坝体填筑材料计算参数进行反馈分析,得出了能够反映坝体实际变形的弹塑性应力变形计算参数,有利于今后建立大坝变形预报模型,更准确地把握大坝实时运行状态。 相似文献
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墙体裂缝的成因及防治 总被引:2,自引:2,他引:0
介绍了墙体裂缝的种类,从地基不均匀下沉、温度变化等方面分析了引起墙体裂缝的原因,介绍了墙体裂缝的预防措施和治理措施,以有效控制墙体裂缝的危害程度。 相似文献
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Comments on an article by Eidelson and Eidelson (see record 2003-03645-004) which made an important contribution, at a critical juncture, to the discussion of international conflicts by identifying core dimensions that allow for the systematic examination of the problem. Their article also posed a danger that mirrors a disturbing trend in the public discourse about conflicts and injustice. In response to the recent escalation of international violence and years of mixed results of engagement in debates centered around grievances of injustice (such as the Palestinian-Israeli conflict), many politicians, pundits, and scholars have advocated addressing conflicts by separating them from the underlying grievances and the ongoing injustice. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献