Potato spindle tuber viroid(PSTVd)disease is one of the major diseases that threatens potato production.Therefore,an advanced,rapid and sensitive detection technology is needed to detect the disease for better control...Potato spindle tuber viroid(PSTVd)disease is one of the major diseases that threatens potato production.Therefore,an advanced,rapid and sensitive detection technology is needed to detect the disease for better control.In order to establish an easier nucleic acid spot hybridization(NASH)method,some studies were tried as the followings:(1)the pre-hybridization step of nucleic acid spot hybridization(NASH)was omitted compared with ordinary way;(2)RNA extraction(phenol extraction and Ames buffer extraction)methods were compared;(3)fixed RNA by UV lamp and oven compared with UV cross-linker;(4)hybridized the RNA in shaking incubator and so on.The results showed that RNA extracted by Ames buffer was more effective than by the phenol extraction method.Besides,the result of hybridization without pre-hybridization step was better than that with 1.5 h of pre-hybridization.The more important discovery was that the shaking incubator could replace the hybridization oven and the ordinary UV lamp could replace the UV cross-linker.After a long term repeated research and testing,a new hybridization system that could rapidly detect the PSTVd by improved NASH technique merely using common instruments and equipment was established.展开更多
Both the primed in situ(PRINS)and the peptide nucleic acid-fluorescence in situ hybridization(PNA-FISH) techniques constitute alternatives to the conventional(fluorescence in situ hybridization,FISH)procedure for chro...Both the primed in situ(PRINS)and the peptide nucleic acid-fluorescence in situ hybridization(PNA-FISH) techniques constitute alternatives to the conventional(fluorescence in situ hybridization,FISH)procedure for chro- mosomal investigations.The PRINS reaction is based on the use of a DNA polymerase and labeled nucleotide in an in situ primer extension reaction.Peptide nucleic acid probes are synthetic DNA analogs with uncharged polyamide backbones.The two procedures present several advantages(specificity,rapidity and discriminating ability)that make them very attractive for cytogenetic purposes.Their adaptation to human spermatozoa has allowed the development of new and fast procedures for the chromosomal screening of male gametes and has provided efficient complements to FISH for in situ assessment of aneuploidy in male gametes.(Asian J Androl 2006 Jul;8:387-392)展开更多
Scirrhous carcinoma is charactertzed by reinarkable amount of collagen fibrils, mainly type I and type III collagens. The origin of collagens is still under debate.cDNA fragments of type I and type III procollagens ...Scirrhous carcinoma is charactertzed by reinarkable amount of collagen fibrils, mainly type I and type III collagens. The origin of collagens is still under debate.cDNA fragments of type I and type III procollagens were subcloned into Gemini pGEM vectors to synthesize the 35Slabeled cRNA probes. By in situ hybridization, we have found the fibroblasts surrounding the tumor cells and cords contained abundent type I and type III procollagen mRNAs which decreased with the distance of fibroblasts from the tumor cells. In all freshly prepared tissues, the tumor cells also contained significant pro α1 (I) and pro α1 (III) mRNAs, but no or little pro α2 (I) mRNA. The results indicated that type I and type III collagens in human scirrhous carcinoma of breast are mainly produced by fibroblasts. Tumor cells also perticipate in the disposition of collagen fibrils, probably type I trimer and type III collagens in accordance with what was observed in biochemical展开更多
The detection and analysis of circulating tumor cells （CTCs） from patients＇ blood is important to assess tumor status; however, it remains a challenge. In the present study, we developed a programmable DNA-responsi...The detection and analysis of circulating tumor cells （CTCs） from patients＇ blood is important to assess tumor status; however, it remains a challenge. In the present study, we developed a programmable DNA-responsive microchip for the highly efficient capture and nondestructive release of CTCs via nucleic acid hybridization. Transparent and patternable substrates with hierarchical architectures were integrated into the microchip with herringbone grooves, resulting in greatly enhanced cell-surface interaction via herringbone micromixers, more binding sites, and better matched topographical interactions. In combination with a high-affinity aptamer, target cancer cells were specifically and efficiently captured on the chip. Captured cancer cells were gently released from the chip under physiological conditions using toehold-mediated strand displacement, without any destructive factors for cells or substrates. More importantly, aptamercontaining DNA sequences on the surface of the retrieved cancer cells could be further amplified by polymerase chain reaction （PCR）, facilitating the detection of cell surface biomarkers and characterization of the CTCs. Furthermore, this system was extensively applied to the capture and release of CTCs from patients＇ blood samples, demonstrating a promising high-performance platform for CTC enrichment, release, and characterization.展开更多
DNA水凝胶是具有三维聚合物网络的高保水性材料。研究人员设计了多种DNA水凝胶交联制备方法,并通过向其中引入其他功能分子或与其他类型的功能材料相互结合,构建了具有优异性能的DNA水凝胶,受到了广泛关注。适配体是基于指数富集的配体...DNA水凝胶是具有三维聚合物网络的高保水性材料。研究人员设计了多种DNA水凝胶交联制备方法,并通过向其中引入其他功能分子或与其他类型的功能材料相互结合,构建了具有优异性能的DNA水凝胶,受到了广泛关注。适配体是基于指数富集的配体系统进化(systematic evolution of ligands by exponential enrichment,SELEX)技术从随机寡核苷酸文库中筛选获得的对目标物质具有良好特异性与亲和力的寡核苷酸序列。适配体功能化的DNA水凝胶具有靶向范围广、稳定性好、易于修饰、操作简单和成本低等优点,得到了广泛应用。本文概述了构建适配体功能化的DNA水凝胶的基本设计原则与分类,重点介绍了适配体功能化的DNA水凝胶在食品安全检测中的最新策略,最后,讨论了适配体功能化的DNA水凝胶面临的挑战以及对未来的展望,旨在为其在食品安全领域的应用提供参考。展开更多
基金Supported by Doctoral Research Startup Project of Zhaotong University。
文摘Potato spindle tuber viroid(PSTVd)disease is one of the major diseases that threatens potato production.Therefore,an advanced,rapid and sensitive detection technology is needed to detect the disease for better control.In order to establish an easier nucleic acid spot hybridization(NASH)method,some studies were tried as the followings:(1)the pre-hybridization step of nucleic acid spot hybridization(NASH)was omitted compared with ordinary way;(2)RNA extraction(phenol extraction and Ames buffer extraction)methods were compared;(3)fixed RNA by UV lamp and oven compared with UV cross-linker;(4)hybridized the RNA in shaking incubator and so on.The results showed that RNA extracted by Ames buffer was more effective than by the phenol extraction method.Besides,the result of hybridization without pre-hybridization step was better than that with 1.5 h of pre-hybridization.The more important discovery was that the shaking incubator could replace the hybridization oven and the ordinary UV lamp could replace the UV cross-linker.After a long term repeated research and testing,a new hybridization system that could rapidly detect the PSTVd by improved NASH technique merely using common instruments and equipment was established.
文摘Both the primed in situ(PRINS)and the peptide nucleic acid-fluorescence in situ hybridization(PNA-FISH) techniques constitute alternatives to the conventional(fluorescence in situ hybridization,FISH)procedure for chro- mosomal investigations.The PRINS reaction is based on the use of a DNA polymerase and labeled nucleotide in an in situ primer extension reaction.Peptide nucleic acid probes are synthetic DNA analogs with uncharged polyamide backbones.The two procedures present several advantages(specificity,rapidity and discriminating ability)that make them very attractive for cytogenetic purposes.Their adaptation to human spermatozoa has allowed the development of new and fast procedures for the chromosomal screening of male gametes and has provided efficient complements to FISH for in situ assessment of aneuploidy in male gametes.(Asian J Androl 2006 Jul;8:387-392)
文摘Scirrhous carcinoma is charactertzed by reinarkable amount of collagen fibrils, mainly type I and type III collagens. The origin of collagens is still under debate.cDNA fragments of type I and type III procollagens were subcloned into Gemini pGEM vectors to synthesize the 35Slabeled cRNA probes. By in situ hybridization, we have found the fibroblasts surrounding the tumor cells and cords contained abundent type I and type III procollagen mRNAs which decreased with the distance of fibroblasts from the tumor cells. In all freshly prepared tissues, the tumor cells also contained significant pro α1 (I) and pro α1 (III) mRNAs, but no or little pro α2 (I) mRNA. The results indicated that type I and type III collagens in human scirrhous carcinoma of breast are mainly produced by fibroblasts. Tumor cells also perticipate in the disposition of collagen fibrils, probably type I trimer and type III collagens in accordance with what was observed in biochemical
基金This work was supported by the National Natural Science Foundation of China （NSFC） （Nos. 21432008, 91413109 and 21575110）. China Postdoctoral Innovative Talent Support Program of China （No. BX201700176）.
文摘The detection and analysis of circulating tumor cells （CTCs） from patients＇ blood is important to assess tumor status; however, it remains a challenge. In the present study, we developed a programmable DNA-responsive microchip for the highly efficient capture and nondestructive release of CTCs via nucleic acid hybridization. Transparent and patternable substrates with hierarchical architectures were integrated into the microchip with herringbone grooves, resulting in greatly enhanced cell-surface interaction via herringbone micromixers, more binding sites, and better matched topographical interactions. In combination with a high-affinity aptamer, target cancer cells were specifically and efficiently captured on the chip. Captured cancer cells were gently released from the chip under physiological conditions using toehold-mediated strand displacement, without any destructive factors for cells or substrates. More importantly, aptamercontaining DNA sequences on the surface of the retrieved cancer cells could be further amplified by polymerase chain reaction （PCR）, facilitating the detection of cell surface biomarkers and characterization of the CTCs. Furthermore, this system was extensively applied to the capture and release of CTCs from patients＇ blood samples, demonstrating a promising high-performance platform for CTC enrichment, release, and characterization.
文摘DNA水凝胶是具有三维聚合物网络的高保水性材料。研究人员设计了多种DNA水凝胶交联制备方法,并通过向其中引入其他功能分子或与其他类型的功能材料相互结合,构建了具有优异性能的DNA水凝胶,受到了广泛关注。适配体是基于指数富集的配体系统进化(systematic evolution of ligands by exponential enrichment,SELEX)技术从随机寡核苷酸文库中筛选获得的对目标物质具有良好特异性与亲和力的寡核苷酸序列。适配体功能化的DNA水凝胶具有靶向范围广、稳定性好、易于修饰、操作简单和成本低等优点,得到了广泛应用。本文概述了构建适配体功能化的DNA水凝胶的基本设计原则与分类,重点介绍了适配体功能化的DNA水凝胶在食品安全检测中的最新策略,最后,讨论了适配体功能化的DNA水凝胶面临的挑战以及对未来的展望,旨在为其在食品安全领域的应用提供参考。
