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61.
Airway mucus overproduction is a distinguishing feature of chronic obstructive pulmonary disease (COPD). LL-37 is the only member of human cathelicidins family of antimicrobial peptides and plays a central role in many immune and inflammatory reactions. Increasing evidence suggests the involvement of LL-37 in the pathogenesis of COPD. Here, we investigated the effects of LL-37 on airway mucus overproduction in COPD. We observed overexpression of both LL-37 and MUC5AC mucin (a major mucin component of mucus) in airways of COPD patients and found a correlation between them. We showed in vitro that LL-37 induces MUC5AC mucin production by airway epithelial NCI-H292 cells in the absence and presence of cigarette smoke extract, with TNF-α converting enzyme (TACE)–EGFR–ERK1/2 pathway and IL-8 required for the induction. Therefore, we concluded that LL-37 enhances the mucus production in COPD airways, thus contributing to the progression of COPD.  相似文献   
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DNA-damage response control of E2F7 and E2F8   总被引:2,自引:0,他引:2  
Here, we report that the two recently identified E2F subunits, E2F7 and E2F8, are induced in cells treated with DNA-damaging agents where they have an important role in dictating the outcome of the DNA-damage response. The DNA-damage-dependent induction coincides with the binding of E2F7 and E2F8 to the promoters of certain E2F-responsive genes, most notably that of the E2F1 gene, in which E2F7 and E2F8 coexist in a DNA-binding complex. As a consequence, E2F7 and E2F8 repress E2F target genes, such as E2F1, and reducing the level of each subunit results in an increase in E2F1 expression and activity. Importantly, depletion of either E2F7 or E2F8 prevents the cell-cycle effects that occur in response to DNA damage. Thus, E2F7 and E2F8 act upstream of E2F1, and influence the ability of cells to undergo a DNA-damage response. E2F7 and E2F8, therefore, underpin the DNA-damage response.  相似文献   
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吴秀杰 《人类学学报》2022,41(4):608-617
自20世纪40年代魏敦瑞提出北京猿人(周口店直立人)可能存在“暴力争斗”和“同类残食”的观点之后,引发了一些学者和科普大众对北京猿人是否为“食人族”的争论。由于原始化石标本在第二次世界大战期间丢失,本文以保存下来的周口店(ZKD)直立人头骨原始模型和素描图为研究材料,对魏敦瑞提出的具有创伤和人工切割痕迹的5件标本(ZKD II、ZKD VI、ZKD X、ZKD XI和ZKD XII)进行辨析。结果显示:1)ZKD X、ZKD XI、ZKD XII这3件标本的头盖部,有7处可以确定为生前遭受非致死性撞击导致的局部创伤;2)ZKD VI头盖骨残片周边的及中央区域的断痕,为个体生前遭受致死性的暴力打击导致;3)ZKD II和ZKD VI顶骨位置疑似人工切割痕迹的沟槽实际上是动物啃咬或自然因素导致的,北京猿人“同类残食”的观点在本文研究中没有得到证实。北京猿人头骨的创伤痕迹都位于头盖部,以顶骨居多,其次为额骨,符合人群之间暴力冲突产生创伤的位置。  相似文献   
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The degenerate primer-based sequencing Was developed by a synthesis method(DP-SBS)for high-throughput DNA sequencing,in which a set of degenerate primers are hybridized on the arrayed DNA templates and extended by DNA polymerase on microarrays.In this method,adifferent set of degenerate primers containing a give nnumber(n)of degenerate nucleotides at the 3'-ends were annealed to the sequenced templates that were immobilized on the solid surface.The nucleotides(n 1)on the template sequences were determined by detecting the incorporation of fluorescent labeled nucleotides.The fluorescent labeled nucleotide was incorporated into the primer in a base-specific manner after the enzymatic primer extension reactions and nine-base length were read out accurately.The main advanmge of the DP-SBS is that the method only uses very conventional biochemical reagents and avoids the complicated special chemical reagents for removing the labeled nucleotides and reactivating the primer for further extension.From the present study,it is found that the DP-SBS method is reliable,simple,and cost-effective for laboratory-sequencing a large amount of short DNA fragments.  相似文献   
66.
Modified nucleoside in urine samples is one of the most common biomarkers for cancer screening. Therefore, we developed a novel detection method for modified nucleoside detection in human urine. In this work, the modified nucleoside from real cancer patient's urine samples was first separated and purified using the affinity chromatography (AC) technology relying on its specific adsorption capacity. Then, surface‐enhanced Raman spectroscopy (SERS) technology with the capability of single molecular detection was used to sensitively characterize the biomolecular features of modified nucleoside. A total of 141 high‐quality SERS spectra of urinary modified nucleoside can be obtained from 50 gastric cancer patients and 43 breast cancer patients, as well as 48 healthy volunteers. Using principal component analysis combined with linear discriminant analysis (PCA‐LDA), the diagnostic sensitivities for identifying gastric cancer vs normal, breast cancer vs normal, gastric cancer vs breast cancer were 84.0%, 76.7% and 82.0%, respectively, and the corresponding diagnostic specificities for each combination were 95.8%, 87.5% and 90.7%, respectively. These results show that this novel method based on urinary modified nucleoside detection combining AC and SERS technologies holds promising potential for developing a specific, non‐invasive and label‐free tool for cancer screening.   相似文献   
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山顶洞101号头骨化石是东亚地区保存最为完整的化石之一,是探讨东亚地区现代人起源的重要研究材料。本文依据数据集中现生人的面部软组织平均分布,提出了计算机三维颅面复原方法,实现了101号头骨生前面貌的预测复原。主要包括三个步骤:首先使用CT完成了101号男性头骨和下颌骨仿制模型的三维重建。然后,利用计算机技术将现生人的面部软组织分布作为101号头骨的面部软组织分布,实现了颅面虚拟复原,并采用手工绘画技巧再现了复原面貌的形态特征。最后,提出了一种基于面部软组织分布和面貌统计形状模型的形态分析方法,实现了颅面复原结果的评估。山顶洞101号头骨的复原面貌具有头部较长、额头前倾、眉弓粗壮等特征,与101号头骨的几何形态基本一致。该技术再现了更新世晚期人类的脑颅及面部的形态特征,为古人类颅面复原的研究提供了技术支持和参考资料。  相似文献   
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(1) A new human glioblastoma multiforme (GBM) cell line, WJ1, was established from the tissue derived from a 29-year-old patient diagnosed with a grade IV GBM. (2) The WJ1 cell line has been subcultured for more than 80 passages in standard culture media without feeder layer or collagen coatings. (3) GBM cells grow in vitro with distinct morphological appearance. Ultrastructural examination revealed large irregular nuclei and pseudo-inclusion bodies in nuclei. The cytoplasm contained numerous immature organelles and a few glia filaments. Growth kinetic studies demonstrated an approximate population doubling time of 60 h and a colony forming efficiency of 4.04%. The karyotype of the cells was hyperdiploid, with a large subpopulation of polyploid cells. Drug sensitivities of DDP, VP-16, tanshinone IIA of this cell line were assayed. They showed a dose- and time-dependent growth inhibition effect on the cells. (4) Orthotopic transplantation of GBM cells into athymic nude mice induced the formation of solid tumor masses about 6 weeks. The cells obtained from mouse tumor masses when cultivated in vitro had the same morphology and ultrastructure as those of the initial cultures. (5) This cell line may provide a useful model in vitro and in vivo in the cellular and molecular studies as well as in testing novel therapies for human glioblastoma multiforme.  相似文献   
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