DNA methylation has been extensively investigated in recent years,not least because of its known relationship with various diseases.Progress in analytical methods can greatly increase the relevance of DNA methylation ...DNA methylation has been extensively investigated in recent years,not least because of its known relationship with various diseases.Progress in analytical methods can greatly increase the relevance of DNA methylation studies to both clinical medicine and scientific research.Microflu-idic chips are excellent carriers for molecular analysis,and their use can provide improvements from multiple aspects.On-chip molecular analysis has received extensive attention owing to its advantages of portability,high throughput,low cost,and high efficiency.In recent years,the use of novel microfluidic chips for DNA methylation analysis has been widely reported and has shown obvious superiority to conventional methods.In this review,wefirst focus on DNA methylation and its applications.Then,we discuss advanced microfluidic-based methods for DNA methylation analysis and describe the great progress that has been made in recent years.Finally,we summarize the advantages that microfluidic technology brings to DNA methylation analysis and describe several challenges and perspectives for on-chip DNA methylation analysis.This review should help researchers improve their understanding and make progress in developing microfluidic-based methods for DNA methylation analysis.展开更多
MtDNA was successfully extracted from ten individual bones (femurs) in the tombs of ancient Jushi in Turfan basin, dated back to the year about 3 000-2 500 years ago. By means of four overlapping primers, we got nucl...MtDNA was successfully extracted from ten individual bones (femurs) in the tombs of ancient Jushi in Turfan basin, dated back to the year about 3 000-2 500 years ago. By means of four overlapping primers, we got nucleotide sequence of the 218bp length. Ancient mtDNA was analyzed by the sequencing of hypervariable region Ⅰ of the mtDNA control region. The result shows that 9 haplotypes with 24 polymorphic sites were obtained. The phylogenetic analysis indicated that Mongolians and Altai are the population genetically closest to the Jushi groups and Jushi mtDNA pool being an admixture of eastern Asian and European lineages. So our preliminary data imply that an ancient mingling of Euro-Asian population had existed in Turfan basin prior to the early Iron Age.展开更多
The stability of the ancient flood control levees is mainly influenced by water level fluctuations, groundwater concentration and rainfalls. This paper takes the Lanxi ancient levee as a research object to study the e...The stability of the ancient flood control levees is mainly influenced by water level fluctuations, groundwater concentration and rainfalls. This paper takes the Lanxi ancient levee as a research object to study the evolution laws of its seepage, displacement and stability before and after reinforcement with the upside-down hanging wells and grouting curtain through numerical simulation methods combined with experiments and observations. The study results indicate that the filled soil is less affected by water level fluctuations and groundwater concentration after reinforcement. A high groundwater level is detrimental to the levee's long-term stability, and the drainage issues need to be fully considered. The deformation of the reinforced levee is effectively controlled since the fill deformation is mainly borne by the upside-down hanging wells. The safety factors of the levee before reinforcement vary significantly with the water level. The minimum value of the safety factors is 0.886 during the water level decreasing period, indicating a very high risk of the instability. While it reached 1.478 after reinforcement, the stability of the ancient levee is improved by a large margin.展开更多
[目的]利用本课题组发展的定量分析方法研究激发态DNA碱基对分子间相互作用的本质,以及不同类型的电子跃迁对DNA碱基对分子间相互作用的影响.[方法]采用广义Kohn-Sham能量分解分析方法(generalized Kohn-Sham based energy decompositio...[目的]利用本课题组发展的定量分析方法研究激发态DNA碱基对分子间相互作用的本质,以及不同类型的电子跃迁对DNA碱基对分子间相互作用的影响.[方法]采用广义Kohn-Sham能量分解分析方法(generalized Kohn-Sham based energy decomposition analysis,GKS-EDA),对两种Waston-Crick构型和两种stacked构型的DNA碱基对分子间相互作用本质进行理论研究.[结果]对于Waston-Crick构型的碱基对,n→π^(*)跃迁削弱了轨道极化作用但加强了电子相关作用,激发态分子间相互作用由电子相关作用主导,而π→π^(*)跃迁对分子间氢键影响较小;对于stacked构型的碱基对,π→π^(*)跃迁削弱了静电相互作用但增强了电子相关作用.[结论]Waston-Crick构型碱基对分子间相互作用本质受电子激发跃迁影响较大,而电子激发跃迁基本不改变stacked构型碱基对分子间相互作用本质.展开更多
乙型肝炎病毒(hepatitis B virus,HBV)e抗原(hepatitis B e antigen,HBeAg)阳性的慢性HBV感染依次经历非活动性肝炎(non-aggressive hepatitis,NAH)和活动性肝炎(aggressive hepatitis,AH)2个分期,但仍缺乏界定HBeAg阳性NAH与AH的可靠...乙型肝炎病毒(hepatitis B virus,HBV)e抗原(hepatitis B e antigen,HBeAg)阳性的慢性HBV感染依次经历非活动性肝炎(non-aggressive hepatitis,NAH)和活动性肝炎(aggressive hepatitis,AH)2个分期,但仍缺乏界定HBeAg阳性NAH与AH的可靠标准。本文根据179例患者的长期随访队列,以自发性HBeAg血清转换作为终点事件,采用Kaplan-Meier生存分析,指定了丙氨酸转氨酶(alanine transaminase,ALT)、HBV表面抗原(hepatitis B surface antigen,HBsAg)和HBV DNA识别HBeAg阳性NAH的功能截断值;在此基础上,评价了ALT串联HBsAg和串联HBV DNA识别HBeAg阳性NAH的性能。结果显示,ALT≤60 IU/L、HBsAg>4.602 log10IU/mL和HBV DNA>7.477 log10IU/mL为识别HBeAg阳性NAH的功能截断值。基于功能截断值,ALT串联HBsAg的患者中,病理学分级≤G1和“分级≤G1且分期≤S2”的构成比均为100%,病理学分期≤S1和“分级≤G2且分期≤S1”的构成比均为68.2%;ALT串联HBV DNA的患者中,病理学分级≤G1和“分级≤G1且分期≤S2”的构成比均为86.2%,病理学分期≤S1和“分级≤G2且分期≤S1”的构成比均为69.0%;ALT串联HBsAg识别病理学分级≤G1和“分级≤G1且分期≤S2”的阳性似然比均为+∞,识别病理学分期≤S1和“分级≤G2且分期≤S1”的阳性似然比均为2.034;ALT串联HBV DNA识别病理学分级≤G1和“分级≤G1且分期≤S2”的阳性似然比分别为3.000和3.068,识别病理学分期≤S1和“分级≤G2且分期≤S1”的阳性似然比均为2.106。以上结果提示,ALT串联HBsAg和串联HBV DNA均可有效识别HBeAg阳性NAH;且ALT串联HBsAg识别HBeAg阳性NAH的性能优于ALT串联HBV DNA。展开更多
目前,DNA甲基化已成为生命科学和医学领域中备受瞩目的研究热点之一,与之相关的文献数量呈现出快速增长的趋势。为深入理解DNA甲基化研究的整体发展历程与趋势,本研究采用文献分析方法,对近30年间Web of Science(WOS)数据库和CNKI数据...目前,DNA甲基化已成为生命科学和医学领域中备受瞩目的研究热点之一,与之相关的文献数量呈现出快速增长的趋势。为深入理解DNA甲基化研究的整体发展历程与趋势,本研究采用文献分析方法,对近30年间Web of Science(WOS)数据库和CNKI数据库中与DNA甲基化相关的文献进行了详细分析,并利用VOSviewer软件进行了可视化处理。检索和分析结果显示,WOS数据库中与DNA甲基化相关文献有21262篇,CNKI数据库有25664篇。在WOS中,美国相关论文数量占有绝对优势,且篇均被引频次和h-指数较高。研究方向主要集中在遗传学、生物化学与分子生物学、肿瘤学这3个方面。关键词主要为“表观遗传学(epigenetics)”、“基因表达(gene-expression)“和”癌症(cancer)”其中基因表达是DNA甲基化研究领域的热点和方向,这些关键词反映了DNA甲基化在这些领域的广泛应用和深入探索。对CNKI数据库分析的结果显示,研究论文主要发表在《癌症》、《中国畜牧兽医》及《畜牧兽医学报》等期刊。本研究通过对WOS和CNKI数据库中DNA甲基化相关文献的深入分析,为后续DNA甲基化领域的研究提供了有价值的信息和参考。展开更多
基金support from the National Key R&D Program of China(Grant No.2018YFE0118700)the National Natural Science Foundation of China(NSFC Grant No.62174119)+1 种基金the 111 Project(Grant No.B07014)the Foundation for Talent Scientists of Nanchang Institute for Microtechnology of Tianjin University.
文摘DNA methylation has been extensively investigated in recent years,not least because of its known relationship with various diseases.Progress in analytical methods can greatly increase the relevance of DNA methylation studies to both clinical medicine and scientific research.Microflu-idic chips are excellent carriers for molecular analysis,and their use can provide improvements from multiple aspects.On-chip molecular analysis has received extensive attention owing to its advantages of portability,high throughput,low cost,and high efficiency.In recent years,the use of novel microfluidic chips for DNA methylation analysis has been widely reported and has shown obvious superiority to conventional methods.In this review,wefirst focus on DNA methylation and its applications.Then,we discuss advanced microfluidic-based methods for DNA methylation analysis and describe the great progress that has been made in recent years.Finally,we summarize the advantages that microfluidic technology brings to DNA methylation analysis and describe several challenges and perspectives for on-chip DNA methylation analysis.This review should help researchers improve their understanding and make progress in developing microfluidic-based methods for DNA methylation analysis.
基金Supported by Fund for the Important Project of the Science and Technology DepartmentMinistry of Education
文摘MtDNA was successfully extracted from ten individual bones (femurs) in the tombs of ancient Jushi in Turfan basin, dated back to the year about 3 000-2 500 years ago. By means of four overlapping primers, we got nucleotide sequence of the 218bp length. Ancient mtDNA was analyzed by the sequencing of hypervariable region Ⅰ of the mtDNA control region. The result shows that 9 haplotypes with 24 polymorphic sites were obtained. The phylogenetic analysis indicated that Mongolians and Altai are the population genetically closest to the Jushi groups and Jushi mtDNA pool being an admixture of eastern Asian and European lineages. So our preliminary data imply that an ancient mingling of Euro-Asian population had existed in Turfan basin prior to the early Iron Age.
基金the scientific research foundation of Zhejiang Provincial Natural Science Foundation of China (LTGG24E090002)Zhejiang University of Water Resources and Electric Power (xky2022013)+1 种基金Major Science and Technology Plan Project of Zhejiang Provincial Department of Water Resources (RA1904)the water conservancy management department, Zhejiang Design Institute of Water Conservancy and Hydro Electric Power Co., Ltd. and the construction company for their support。
文摘The stability of the ancient flood control levees is mainly influenced by water level fluctuations, groundwater concentration and rainfalls. This paper takes the Lanxi ancient levee as a research object to study the evolution laws of its seepage, displacement and stability before and after reinforcement with the upside-down hanging wells and grouting curtain through numerical simulation methods combined with experiments and observations. The study results indicate that the filled soil is less affected by water level fluctuations and groundwater concentration after reinforcement. A high groundwater level is detrimental to the levee's long-term stability, and the drainage issues need to be fully considered. The deformation of the reinforced levee is effectively controlled since the fill deformation is mainly borne by the upside-down hanging wells. The safety factors of the levee before reinforcement vary significantly with the water level. The minimum value of the safety factors is 0.886 during the water level decreasing period, indicating a very high risk of the instability. While it reached 1.478 after reinforcement, the stability of the ancient levee is improved by a large margin.
文摘[目的]利用本课题组发展的定量分析方法研究激发态DNA碱基对分子间相互作用的本质,以及不同类型的电子跃迁对DNA碱基对分子间相互作用的影响.[方法]采用广义Kohn-Sham能量分解分析方法(generalized Kohn-Sham based energy decomposition analysis,GKS-EDA),对两种Waston-Crick构型和两种stacked构型的DNA碱基对分子间相互作用本质进行理论研究.[结果]对于Waston-Crick构型的碱基对,n→π^(*)跃迁削弱了轨道极化作用但加强了电子相关作用,激发态分子间相互作用由电子相关作用主导,而π→π^(*)跃迁对分子间氢键影响较小;对于stacked构型的碱基对,π→π^(*)跃迁削弱了静电相互作用但增强了电子相关作用.[结论]Waston-Crick构型碱基对分子间相互作用本质受电子激发跃迁影响较大,而电子激发跃迁基本不改变stacked构型碱基对分子间相互作用本质.
文摘目的探讨在HPV阳性女性中,液基细胞学、DNA倍体分析及P16/Ki-67双染检测对宫颈癌前病变的分流作用。方法回顾性分析2021年5月至2022年12月在我院妇科行阴道镜及宫颈活检的妇女590例。患者高危人乳头瘤病毒(human papilloma virus,HPV)检测阳性,且行液基细胞学(liquid-based cytology,LBC)、DNA倍体分析、P16/Ki-67双染3种检查,对上述3种方法的灵敏度、特异性、受试者工作特征(receiver operating characteristic,ROC)曲线进行统计分析。结果液基细胞学、DNA倍体分析和P16/Ki-67双染3种筛查方法对宫颈癌前病变的灵敏度分别为84.2%、77.5%、76.4%,特异性分别为40.7%、49.2%、70.1%,曲线下面积(area under the curve,AUC)分别是0.625、0.634、0.733,其中,P16/Ki-67双染检测显著优于液基细胞学检查及DNA倍体分析(P<0.0001)。结论本研究认为,在HPV阳性女性中,P16/Ki-67双染检测的分流效果最佳。
文摘目前,DNA甲基化已成为生命科学和医学领域中备受瞩目的研究热点之一,与之相关的文献数量呈现出快速增长的趋势。为深入理解DNA甲基化研究的整体发展历程与趋势,本研究采用文献分析方法,对近30年间Web of Science(WOS)数据库和CNKI数据库中与DNA甲基化相关的文献进行了详细分析,并利用VOSviewer软件进行了可视化处理。检索和分析结果显示,WOS数据库中与DNA甲基化相关文献有21262篇,CNKI数据库有25664篇。在WOS中,美国相关论文数量占有绝对优势,且篇均被引频次和h-指数较高。研究方向主要集中在遗传学、生物化学与分子生物学、肿瘤学这3个方面。关键词主要为“表观遗传学(epigenetics)”、“基因表达(gene-expression)“和”癌症(cancer)”其中基因表达是DNA甲基化研究领域的热点和方向,这些关键词反映了DNA甲基化在这些领域的广泛应用和深入探索。对CNKI数据库分析的结果显示,研究论文主要发表在《癌症》、《中国畜牧兽医》及《畜牧兽医学报》等期刊。本研究通过对WOS和CNKI数据库中DNA甲基化相关文献的深入分析,为后续DNA甲基化领域的研究提供了有价值的信息和参考。
