An integrated microfluidic system for screening of phage-displayed peptides specific to colon cancer cells and colon cancer stem cells

Affinity reagents recognizing biomarkers specifically are essential components of clinical diagnostics and target therapeutics. However, conventional methods for screening of these reagents often have drawbacks such as large reagent consumption, the labor-intensive or time-consuming procedures, and the involvement of bulky or expensive equipment. Alternatively, microfluidic platforms could potentially automate the screening process within a shorter period of time and reduce reagent and sample consumption dramatically. It has been demonstrated recently that a subpopulation of tumor cells known as cancer stem cells possess high drug resistance and proliferation potential and are regarded as the main cause of metastasis. Therefore, a peptide that recognizes cancer stem cells and differentiates them from other cancer cells will be extremely useful in early diagnosis and target therapy. This study utilized M13 phage display technology to identify peptides that bind, respectively, to colon cancer cells and colon cancer stem cells using an integrated microfluidic system. In addition to positive selection, a negative selection process was integrated on the chip to achieve the selection of peptides of high affinity and specificity. We successfully screened three peptides specific to colon cancer cells and colon cancer stem cells, namely, HOLC-1, HOLC-2, and COLC-1, respectively, and their specificity was measured by the capture rate between target, control, and other cell lines. The capture rates are 43.40 ± 7.23%, 45.16 ± 7.12%, and 49.79 ± 5.34% for colon cancer cells and colon cancer stem cells, respectively, showing a higher specificity on target cells than on control and other cell lines. The developed technique may be promising for early diagnosis of cancer cells and target therapeutics.     

党风廉政建设视域下举报人安全机制的构建

举报对加强党风廉政建设具有非常重要的作用。然而,现在的举报制度和保护措施不健全,造成举报人屡受伤害,扼杀了举报的积极性。鉴于此,国家应该加强机制建设,制定专门的法律保护举报人,实行泄露举报人信息问责制,建立中央直管的举报信息系统,完善举报人救助制度,发挥媒体的舆论引导作用,让举报成为人民监督的重要手段。     

低压配电系统无功补偿柜的设计

无功功率补偿将降低供电系统的功率损耗和电能损耗,减少变压器和线路中的电压损失和提高供电设备利用率。试通过鸡西赫阳燃气有限公司低压配电系统无功补偿柜的设计过程来阐述低压配电系统无功补偿方式选择及无功补偿容量的确定。     

Antioxidants in aqueous extract of Myristica fragrans (Houtt.) suppress mitosis and cyclophosphamide-induced chromosomal aberrations in Allium cepa L. cells

In this study, freeze-dried water extract from the leaves of Myristica fragrans (Houtt.) was tested for mutagenic and antimutagenic potentials using the Allium cepa assay. Freeze-dried water extract alone and its combination with cyclophosphamide (CP) (50 mg/kg) were separately dissolved in tap water at 500, 1000, 2000, and 4000 mg/kg. Onions (A. cepa) were suspended in the solutions and controls for 48 h in the dark. Root tips were prepared for microscopic evaluation. 2,2-Diphenyl-1-picrylhydrazyl (DPPH) free radicals’ scavenging power of the extract was tested using butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT) as standards. Water extract of Myristica fragrans scavenged free radicals better than BHA, but worse than BHT. The extract alone, as well as in combination with CP suppressed cell division, and induced chromosomal aberrations that were insignificantly different from the negative control (P≤0.05). However, cytotoxic and mutagenic actions of CP were considerably suppressed. The observed effects on cell division and chromosomes of A. cepa may be principally connected to the antioxidant properties of the extract. The obtained results suggest mitodepressive and antimutagenic potentials of water extract of the leaves of M. fragrans as desirable properties of a promising anticancer agent.     

Reconceptualizing student ratings of teaching to support quality discourse on student learning: a systems perspective

Higher Education - This paper summarizes the discourse on student ratings of teaching in higher education. It reconceptualizes student ratings within a larger process of promoting quality in...     

“双减”政策背景下青少年体育活动开展策略研究

为了在“双减”政策背景下进一步推进青少年体育活动的开展,通过文献资料法、综合分析法等研究方法,分析了目前青少年体育活动面临的一些问题,并提出如下对策:树立正确的体育价值观,强化体育意识的培养;扩大资源的有效供给,推动青少年体育活动的开展;发挥“家、校、社”主导作用,切实建设联动共同体;建立长效保障机制和治理监管体系,有效防范化解各类风险。     

Synthesis of singly-terminated ladder networks by multivariable array using homogeneous polynomials

This paper discusses a multivariable array whose elements are multivariable homogeneous polynomials which may have missing terms in any of the variables. This array permits one to obtain conditions for the realizability of a driving-point function or a transfer function as a resistively terminated low-pass ladder network. By reac- tance transformations, other forms of ladder structures can be obtained. The case of cascade-separable ladder networks is discussed in detail.     

知识考古与历史重诂:编撰《林纾年谱长编》的构想

论述编撰《林纾年谱长编》的总体构想。课题尝试运用现代史学方法对近代闽籍历史名人林纾进行知识考古和重诂,涉及谱主一生四个不同特质的时期。介绍这项课题的选题背景、动机和主要任务,同时提出年谱编撰方法方面的新观点。研究的目的是以新的历史观重构特定时期的历史人物。     

“数字中国”布局下我国城建档案馆数字化转型之思考

"数字中国"布局下,城建档案馆将为智慧城市规划与建设提供可靠的档案数据支持。城建档案馆行政执法过程中面临缺少上位法、缺少行政许可、与上级行政主管部门职能交叉等问题,亟待解决。在数字化城建档案馆建设的进程中,受"放管服"行政指引,城建档案馆应通过削减前置审批、强制归档、智能+创新服务三个方面构建数字化管理新机制,实现智慧化活态城建档案馆的整体目标。通过完善依法行政、对接征信体系、技术迭代推进数字化进程,将智能化行政与智慧化服务并行,最终接入国家政务服务平台,实现全国"一网通办"的政务目标。     

The neutrophil-lymphocyte ratio to predict poor prognosis of critical acute myocardial infarction patients: a retrospective cohort study

IntroductionInflammation is closely related to adverse outcomes of acute myocardial infarction (AMI). This study aimed to evaluate whether neutrophil-lymphocyte ratio (NLR) can predict poor prognosis of critical AMI patients.Materials and methodsWe designed a retrospective cohort study and extracted AMI patients from the “Medical Information Mart for Intensive Care-III” database. The primary outcome was 1-year all-cause mortality. The secondary outcomes were 90-day and in-hospital all-cause mortalities, and acute kidney injury (AKI) incidence. The optimal cut-offs of NLR were picked by X-tile software according to the 1-year mortality and patient groups were created: low-NLR (< 4.8), high-NLR (4.8 - 21.1), and very high-NLR (> 21.1). Cox and modified Poisson regression models were used to evaluate the effect of NLR on outcomes in critically AMI patients.ResultsFinally, 782 critical AMI patients were enrolled in this study, and the 1-year mortality was 32% (249/782). The high- and very high-NLR groups had a higher incidence of outcomes than the low-NLR group (P < 0.05). The multivariate regression analyses found that the high- and very high-NLR groups had a higher risk of 1-year mortality (Hazard ratio (HR) = 1.59, 95% CI: 1.12 to 2.24, P = 0.009 and HR = 1.73, 95% CI: 1.09 to 2.73, P = 0.020), 90-day mortality (HR = 1.69, 95% CI: 1.13 to 2.54, P = 0.011 and HR = 1.90, 95% CI: 1.13 to 3.20, P = 0.016), in-hospital mortality (Relative risk (RR) = 1.77, 95% CI: 1.14 to 2.74, P = 0.010 and RR = 2.10, 95% CI: 1.23 to 3.58, P = 0.007), and AKI incidence (RR = 1.44, 95% CI: 1.06 to 1.95, P = 0.018 and RR = 1.34, 95% CI: 0.87 to 2.07, P = 0.180) compared with low-NLR group. NLR retained stable predictive ability in sensitivity analyses.ConclusionBaseline NLR is an independent risk factor for 1-year mortality, 90-day mortality, in-hospital mortality, and AKI incidence in AMI patients.