Objective: Xueteng-related herbs include Spatholobi Caulis(Jixueteng in Chinese), Sargentodoxae Caulis(Daxueteng in Chinese), Kadsurae Caulis(Dianjixueteng in Chinese), and other medicinal plant stems that release red...Objective: Xueteng-related herbs include Spatholobi Caulis(Jixueteng in Chinese), Sargentodoxae Caulis(Daxueteng in Chinese), Kadsurae Caulis(Dianjixueteng in Chinese), and other medicinal plant stems that release reddish-brown juices after being cut. However, similarity in phonetic spelling and sound leads to their misuse in clinic or commercial circulation. Accurate labeling is imperative as well as effective for species identification.Methods: In this study, the ITS2 sequences of 76 samples of Xueteng-related herbs were obtained and analyzed to identify them. And then they were converted into QR codes using the open source PHP QR code. Also, a DNA barcode reference library was established according to these sequences and was used to authenticate the 25 samples of Xueteng-related herbs collected from the market.Results: The lengths of the ITS2 sequences of different Xueteng-related herbs ranged from 207 to 235 bp and the GC contents were 57.5%-71.0%. Jixueteng, Daxueteng, and Dianjixueteng were clustered into three clades respectively in the neighbor-joining(NJ) phylogenetic tree, and the efficiency of the BLAST method was 100%. The ITS2 sequences of different Xueteng-related herbs were presented vividly and specifically in QR code. Twenty-two of all 25 commercial samples were consistent with the original labels, whereas three samples marked "Dianjixueteng" were authenticated as "Jixueteng".Conclusion: QR code labeling system based on DNA barcode is an effective labeling system of Xuetengrelated herbs for their circulation regulation.展开更多
Bioorthogonal cleavage and ligation reactions together form one more integrated system about the repertoire of bioorthogonal chemistry,capacitating an array of thrilling new biological applications.The bond-cleavage t...Bioorthogonal cleavage and ligation reactions together form one more integrated system about the repertoire of bioorthogonal chemistry,capacitating an array of thrilling new biological applications.The bond-cleavage type and position of biomolecular remain a great challenge,which determines the metabolic pathway of the targets in living systems.Herein we designed two linkages of methylene and carbonyl group attached the N-3 position of the 5-ethynyl-2’-deoxyuridine(EdU)base or the oxygen atom at deoxyribose 3’position to a photocaging group,which would be cleaved by irradiation with 365 nm ultraviolet light.EdU derivatives linked by methylene at the N-3 position had better photodecage efficiency and stability in the absence of light.This paper provides a strategy for studying the nucleoside metabolic pathways in cells,which can easily and conveniently evaluate the effect of the position and type of the linkages.The developed strategy affords a reference for controlling spatial and temporal metabolism of small-molecule drugs,allowing direct manipulation of intact cells under physiological conditions.展开更多
Let k ? 2, 1 ? i ? k and α ? 1 be three integers. For any multiset which consists of some k-long oligonucleotides, a DNA labelled graph is defined as follows: each oligonucleotide from the multiset becomes a point; t...Let k ? 2, 1 ? i ? k and α ? 1 be three integers. For any multiset which consists of some k-long oligonucleotides, a DNA labelled graph is defined as follows: each oligonucleotide from the multiset becomes a point; two points are connected by an arc from the first point to the second one if the i rightmost nucleotides of the first point overlap with the i leftmost nucleotides of the second one. We say that a directed graph D can be (k, i; α)-labelled if it is possible to assign a label (l 1(x), ..., l k (x)) to each point x of D such that l j (x) ? {0, ..., α ? 1} for any j ? {1, ..., k} and (x, y) ? E(D) if and only if (l k?i+1(x), ..., l k (x)) = (l 1(y), ..., l i (y)). By the biological background, a directed graph is a DNA labelled graph if there exist two integers k, i such that it is (k, i; 4)-labelled. In this paper, a detailed discussion of DNA labelled graphs is given. Firstly, we study the relationship between DNA labelled graphs and some existing directed graph classes. Secondly, it is shown that for any DNA labelled graph, there exists a positive integer i such that it is (2i, i; 4)-labelled. Furthermore, the smallest i is determined, and a polynomial-time algorithm is introduced to give a (2i, i; 4)-labelling for a given DNA labelled graph. Finally, a DNA algorithm is given to find all paths from one given point to another in a (2i, i; 4)-labelled directed graph.展开更多
A commercially available non—radioactive DNA labelling kit "enhanced chemiluminescence"(ECL) was evaluated for the diagnosis of falciparum malaria. The results showed that ECL labeled probe successfully det...A commercially available non—radioactive DNA labelling kit "enhanced chemiluminescence"(ECL) was evaluated for the diagnosis of falciparum malaria. The results showed that ECL labeled probe successfully detected as little as 25 pg. Purified DNA of 0.001％ parasitemia of cultured Plasmodium falciparum and did not react with human展开更多
Precise fluorescence imaging of single l-DNA molecules for base pair distance analysis requires a superresolution technique, as these distances are on the order of diffraction limit. Individual l-DNA molecules interca...Precise fluorescence imaging of single l-DNA molecules for base pair distance analysis requires a superresolution technique, as these distances are on the order of diffraction limit. Individual l-DNA molecules intercalated with the fluorescent dye YOYO-1 were investigated at subdiffraction spatial resolution by direct stochastic optical reconstruction microscopy（d STORM）. Various dye-to-DNA base pair ratios were imaged by photoswitching YOYO-1 between the fluorescent state and the dark state using two laser sources. The acquired images were reconstructed into a super-resolution image by applying Gaussian fitting to the centroid of the point spread function. By measuring the distances between localized fluorophores, the base pair distances in single DNA molecules for dye-to-DNA base pair ratios of 1：50,1：100, and 1：500 were calculated to be 17.1 0.8 nm, 34.3 2.2 nm, and 170.3 8.1 nm[17_TD$IF], respectively,which were in agreement with theoretical values. These results demonstrate that intercalating dye in a single DNA molecule can be photoswitched without the use of an activator fluorophore, and that super-localization precision at a spatial resolution of 17 nm was experimentally achieved.展开更多
A new rapid technique for intrahepatic and extrahepatic HBV DNA detection by using digoxigenin labelled probe with in situ hybridization was developed.This technique has the advantage of being non-radioactive and a qu...A new rapid technique for intrahepatic and extrahepatic HBV DNA detection by using digoxigenin labelled probe with in situ hybridization was developed.This technique has the advantage of being non-radioactive and a quick procedure yielding stable results and showing a clear background.展开更多
基金supported by the CAMS Innovation Fund for Medical Sciences(CIFMS,2016-I2M-3-016)the Key Projects of the National Science and Technology Pillar Program(No.2011BAI07B08)
文摘Objective: Xueteng-related herbs include Spatholobi Caulis(Jixueteng in Chinese), Sargentodoxae Caulis(Daxueteng in Chinese), Kadsurae Caulis(Dianjixueteng in Chinese), and other medicinal plant stems that release reddish-brown juices after being cut. However, similarity in phonetic spelling and sound leads to their misuse in clinic or commercial circulation. Accurate labeling is imperative as well as effective for species identification.Methods: In this study, the ITS2 sequences of 76 samples of Xueteng-related herbs were obtained and analyzed to identify them. And then they were converted into QR codes using the open source PHP QR code. Also, a DNA barcode reference library was established according to these sequences and was used to authenticate the 25 samples of Xueteng-related herbs collected from the market.Results: The lengths of the ITS2 sequences of different Xueteng-related herbs ranged from 207 to 235 bp and the GC contents were 57.5%-71.0%. Jixueteng, Daxueteng, and Dianjixueteng were clustered into three clades respectively in the neighbor-joining(NJ) phylogenetic tree, and the efficiency of the BLAST method was 100%. The ITS2 sequences of different Xueteng-related herbs were presented vividly and specifically in QR code. Twenty-two of all 25 commercial samples were consistent with the original labels, whereas three samples marked "Dianjixueteng" were authenticated as "Jixueteng".Conclusion: QR code labeling system based on DNA barcode is an effective labeling system of Xuetengrelated herbs for their circulation regulation.
基金supported by the National Natural Science Foundation of China(Nos.21432008,91753201 and 21721005)the large-scale instrument and equipment sharing foundation of Wuhan University。
文摘Bioorthogonal cleavage and ligation reactions together form one more integrated system about the repertoire of bioorthogonal chemistry,capacitating an array of thrilling new biological applications.The bond-cleavage type and position of biomolecular remain a great challenge,which determines the metabolic pathway of the targets in living systems.Herein we designed two linkages of methylene and carbonyl group attached the N-3 position of the 5-ethynyl-2’-deoxyuridine(EdU)base or the oxygen atom at deoxyribose 3’position to a photocaging group,which would be cleaved by irradiation with 365 nm ultraviolet light.EdU derivatives linked by methylene at the N-3 position had better photodecage efficiency and stability in the absence of light.This paper provides a strategy for studying the nucleoside metabolic pathways in cells,which can easily and conveniently evaluate the effect of the position and type of the linkages.The developed strategy affords a reference for controlling spatial and temporal metabolism of small-molecule drugs,allowing direct manipulation of intact cells under physiological conditions.
基金the National Natural Science Foundation of China (Grant No. 10471081)
文摘Let k ? 2, 1 ? i ? k and α ? 1 be three integers. For any multiset which consists of some k-long oligonucleotides, a DNA labelled graph is defined as follows: each oligonucleotide from the multiset becomes a point; two points are connected by an arc from the first point to the second one if the i rightmost nucleotides of the first point overlap with the i leftmost nucleotides of the second one. We say that a directed graph D can be (k, i; α)-labelled if it is possible to assign a label (l 1(x), ..., l k (x)) to each point x of D such that l j (x) ? {0, ..., α ? 1} for any j ? {1, ..., k} and (x, y) ? E(D) if and only if (l k?i+1(x), ..., l k (x)) = (l 1(y), ..., l i (y)). By the biological background, a directed graph is a DNA labelled graph if there exist two integers k, i such that it is (k, i; 4)-labelled. In this paper, a detailed discussion of DNA labelled graphs is given. Firstly, we study the relationship between DNA labelled graphs and some existing directed graph classes. Secondly, it is shown that for any DNA labelled graph, there exists a positive integer i such that it is (2i, i; 4)-labelled. Furthermore, the smallest i is determined, and a polynomial-time algorithm is introduced to give a (2i, i; 4)-labelling for a given DNA labelled graph. Finally, a DNA algorithm is given to find all paths from one given point to another in a (2i, i; 4)-labelled directed graph.
文摘A commercially available non—radioactive DNA labelling kit "enhanced chemiluminescence"(ECL) was evaluated for the diagnosis of falciparum malaria. The results showed that ECL labeled probe successfully detected as little as 25 pg. Purified DNA of 0.001％ parasitemia of cultured Plasmodium falciparum and did not react with human
基金supported by a grant from Kyung Hee University in 2015(No.KHU-20150618)
文摘Precise fluorescence imaging of single l-DNA molecules for base pair distance analysis requires a superresolution technique, as these distances are on the order of diffraction limit. Individual l-DNA molecules intercalated with the fluorescent dye YOYO-1 were investigated at subdiffraction spatial resolution by direct stochastic optical reconstruction microscopy（d STORM）. Various dye-to-DNA base pair ratios were imaged by photoswitching YOYO-1 between the fluorescent state and the dark state using two laser sources. The acquired images were reconstructed into a super-resolution image by applying Gaussian fitting to the centroid of the point spread function. By measuring the distances between localized fluorophores, the base pair distances in single DNA molecules for dye-to-DNA base pair ratios of 1：50,1：100, and 1：500 were calculated to be 17.1 0.8 nm, 34.3 2.2 nm, and 170.3 8.1 nm[17_TD$IF], respectively,which were in agreement with theoretical values. These results demonstrate that intercalating dye in a single DNA molecule can be photoswitched without the use of an activator fluorophore, and that super-localization precision at a spatial resolution of 17 nm was experimentally achieved.
文摘A new rapid technique for intrahepatic and extrahepatic HBV DNA detection by using digoxigenin labelled probe with in situ hybridization was developed.This technique has the advantage of being non-radioactive and a quick procedure yielding stable results and showing a clear background.
