Dot-blot hybridization was applied in this paper to detect five viruses infecting cucurbitaceous crops, Zuccini yellow mosaic virus （ZYMV）, Watermelon mosaic virus （WMV）, Cucumber mosaic virus （CMV）, Papaya ring...Dot-blot hybridization was applied in this paper to detect five viruses infecting cucurbitaceous crops, Zuccini yellow mosaic virus （ZYMV）, Watermelon mosaic virus （WMV）, Cucumber mosaic virus （CMV）, Papaya ringspot viruswatermelon strain （PRSV-W） and Squash mosaic virus （SqMV）, as a good alternative assay in seed health test and epidemiological and transgenic research. Digoxigenin-labelled cDNA probes of the five viruses were synthesized by PCR with the specific primers and applied in dot-blot hybridization to detect five viruses in crude extraction of the infected leaves. And three SqMV probes of different lengths （0.55, 1.6, and 2.7 kb, respectively） were designed to investigate the effect of hybridization. The results showed that the sensitivity for detecting the crude extraction of infected leaves by ZYMV, WMV, CMV, PRSV-W, and SqMV was down to 1：160, 1：160, 1：320, 1：160, and 1：320, respectively. Three SqMV probes of different length showed no differences on the sensitivity and specificity. The digoxigenin-labelled probes prepared by PCR could be used for accurate and rapid identification of 5 viruses infecting cucurbitaceous crops with good stabilities, sensitivities, specificity, and reproducibilifies.展开更多
The MINimal emission FLUXes(MINFLUX)technique in optical microscopy,widely recognized as the next innovative fluorescence microscopy method,claims a spatial resolution of 1-3 nm in both dead and living cells.To make u...The MINimal emission FLUXes(MINFLUX)technique in optical microscopy,widely recognized as the next innovative fluorescence microscopy method,claims a spatial resolution of 1-3 nm in both dead and living cells.To make use of the full resolution of the MINFLUX microscope,it is important to select appropriate fluorescence probes and labeling strategies,especially in living-cell imaging.This paper mainly focuses on recent applications and developments of fluorescence probes and the relevant labeling strategy for MINFLUX microscopy.Moreover,we discuss the deficiencies that need to be addressed in the future and a plan for the possible progression of MINFLUX to help investigators who have been involved in or are just starting in the field of super-resolution imaging microscopy with theoretical support.展开更多
We demonstrate the feasibility of simultancous multi-probe detection for an optcal-resolution photoacoustic microscopy(OR-PAM)system.OR-P AM has elicited the attention of biomedical imaging researchers because of its ...We demonstrate the feasibility of simultancous multi-probe detection for an optcal-resolution photoacoustic microscopy(OR-PAM)system.OR-P AM has elicited the attention of biomedical imaging researchers because of its optical absorption contrast and high spatial resolution with great imaging depth.OR-PAM allows label-free and noninvasive imaging by maximizing the optical absorption of endogenous biomolecules.However,given the inadequate absoption of some biomolcules,detection sensitivity at the same incident intensity requires improvement.In this study,a modulated continuous wave with power density less than 3mW/cm^(2)(1/4 of the ANSI safety limit)excited the weak photoacoustic(PA)signals of biological cells.A microcavity traneducer is developed based on the bulk modulus of gas five orders of magnitude lower than that of solid;air pressure variation is inversely proportional to cavity volume at the same temperature increase.Considering that a PA wave expands in various directions,detecting PA signals from different positions and adding them together can increase detection sensitivity and signal-to-noise ratio.Therefore,we employ four detectors to acquire tiny PA signals simul-taneously.Experimental results show that the developed OR-PAM system allows the label-free imaging of cells with weak optical absorption.展开更多
Octadecylamine was derivatized with dansyl chloride (5-dimethylaminonaphthalene-1-sulfonyl chloride) In order to simplify and understand the LB films of fluorescent probe labeling proteins. its monolayer and multilaye...Octadecylamine was derivatized with dansyl chloride (5-dimethylaminonaphthalene-1-sulfonyl chloride) In order to simplify and understand the LB films of fluorescent probe labeling proteins. its monolayer and multilayers in the absence and presence of stearic acid were deposited by LB technique. Fluorescence spectra and lifetimes of the fluorescent products were studied to elucidate the microenvironment of molecules in the LB films.展开更多
Altered metabolism has long been recognized as a central hallmark of cancer;however,in the fluorescence imaging field,few studies have been conducted to label tumors by exploiting metabolic differences between cancer ...Altered metabolism has long been recognized as a central hallmark of cancer;however,in the fluorescence imaging field,few studies have been conducted to label tumors by exploiting metabolic differences between cancer cells and normal cells.In this work,we successfully developed a metabolic probe MB-C for specific imaging of glutathione(GSH)dynamic metabolic pathways.GSH was endogenously metabolized to produce SO_(2)via Na_(2)S_(2)O_(3) and thiosulfate sulfurtransferase,equilibrating with sulfites/bisulfites.MB-C was allowed to be activated by GSH along with multi-fluorescence emission increased in red and green channels and further sequence-response metabolites(SO_(2))of GSH in significant fluorescence ratio change of red and green channels.Furthermore,such evident fluorescence ratio changes could be used to distinguish cancer cells from normal cells and identify tumor and normal tissues.Therefore,GSH metabolic imaging was successfully applied to accurately label tumors,which provides a new idea and practical case for the precise visualization of malignant tumors.展开更多
Protein labeling by using a protein tag and tag-specific fluorescent probes is increasingly becoming a useful technique for the real-time imaging of proteins in living cells. SNAP-tag as one of the most prominent fusi...Protein labeling by using a protein tag and tag-specific fluorescent probes is increasingly becoming a useful technique for the real-time imaging of proteins in living cells. SNAP-tag as one of the most prominent fusion tags has been widely used and already commercially available. Recently, various fluorogenic probes for SNAP-tag based protein labeling were reported. Owing to turn-on fluorescence response, fluorogenic probes for SNAP-tag minimize the fluorescence background caused by unreacted or nonspecifically bound probes and allow for direct imaging in living cells without wash-out steps. Thus,real-time analysis of protein localization, dynamics and interactions has been made possible by SNAP-tag fluorogenic probes. In this review,we describe the design strategies of fluorogenic probes for SNAP-tag and their applications in cellular protein labeling.展开更多
In this study,the DNA probe pPF14 was nonradioactively labelled by sulfo-modifica-tion,and used in a dot blot hybridization assay for detection of P.falciparum.The resultsshowed that the sulfoprobe successfully detect...In this study,the DNA probe pPF14 was nonradioactively labelled by sulfo-modifica-tion,and used in a dot blot hybridization assay for detection of P.falciparum.The resultsshowed that the sulfoprobe successfully detected 25pg purified DNA and 0.001% parasitemia ofcultured P.falciparum,and did not react with human leukocyte DNA.In the study of 179clinical blood samples of malaria patients from Yunnan province,the DNA probe results corre-lated well with blood smear ones.Of 107 P.falciparum samples determined by microscope ex-amination,99 were positive by sulfoprobe (92.5%);Of 72 P.vivax samples,1 was crosslyreacted;no cross reactions were found with any of 48 normal blood samples.It is indicated thatsulfoprobe may be useful in specific diagnosis and epidemiological investigation of P.falciparuminfection.展开更多
Objective To explore if strand breaks of DNA in human early chorionic villus cells in uterus were induced by diagnostic ultrasound and to evaluate the method used for detection of single-stranded breaks and double-str...Objective To explore if strand breaks of DNA in human early chorionic villus cells in uterus were induced by diagnostic ultrasound and to evaluate the method used for detection of single-stranded breaks and double-stranded breaks in human DNA. Methods 60 normal pregnant women aged 20-30, who underwent artificial abortion during 6-8 weeks of gestation, were randomly divided into 2 experimental groups: All 30 cases were exposed to diagnostic ultrasound in uterus for 10 minutes, and 24 hours later chorionic villi were extracted; the other 30 cases were taken as the control group. Single-stranded DNA and double-stranded DNA in villus cells in all cases were isolated by the alkaline unwinding combined with hydroxylapatite chromatography, and were quantitatively detected using 32 P-labeled Alu probe for dot-blotting hybridization. Results There was no significant difference in quantity and percentage in single-stranded DNA and double-stranded DNA between 2 groups (P>0.05). 32 P-Alu probe could only hybridize with human DNA, and could detect DNA isolated from as few as 2.5×10 3 chorionic villus cells and 0.45ng DNA in human leukocytes. Conclusion The results suggested that there were no DNA strand damages in human chorionic villus cells when the uterus was exposed to diagnostic ultrasound for 10 minutes. The method,^(32)P-Alu probe for dot-blotting hybridization, was even more specific, sensitive and accurate than conventional approaches.展开更多
As a cornerstone of the central dogma of molecular biology,RNA plays vital roles in living organisms.Over the past few decades,many RNA labeling technologies have been developed to elucidate the biological function of...As a cornerstone of the central dogma of molecular biology,RNA plays vital roles in living organisms.Over the past few decades,many RNA labeling technologies have been developed to elucidate the biological function of RNA.These technologies have signifi-cantly advanced our understanding of RNA secondary structure,localization,and turnover.Additionally,taking advantage of these innovative RNA labeling approaches,plenty of tool kits have been devised for the regulation of RNA-related biological process,such as gene expression and gene editing.In this review,we primarily focus on an array of intracellular RNA labeling methods,encom-passing chemical probes-based labeling,metabolic labeling,and proximity-dependent labeling.We also provide a brief overview of their applications in the research of RNA biology.Finally,the perspectives of RNA labeling are also discussed.展开更多
The synthesis of a novel long-wavelength fluorescent probe, 3-epoxypropoxy fluorescein, and its properties for labeling of histidine are briefly described in this communication. The probe is highly selective for histi...The synthesis of a novel long-wavelength fluorescent probe, 3-epoxypropoxy fluorescein, and its properties for labeling of histidine are briefly described in this communication. The probe is highly selective for histidine, and other amino acids with a concentration of 1 000 times higher than that of histidine did not show noticeable interferences. As an application of this probe, fluorescent labeling of histidine in human serum was attempted and the obtained results were in agreement with those given by using histidine-nickel complex adsorptive voltammetry, both of which were within the normal range of the results reported in literatures.展开更多
文摘Dot-blot hybridization was applied in this paper to detect five viruses infecting cucurbitaceous crops, Zuccini yellow mosaic virus （ZYMV）, Watermelon mosaic virus （WMV）, Cucumber mosaic virus （CMV）, Papaya ringspot viruswatermelon strain （PRSV-W） and Squash mosaic virus （SqMV）, as a good alternative assay in seed health test and epidemiological and transgenic research. Digoxigenin-labelled cDNA probes of the five viruses were synthesized by PCR with the specific primers and applied in dot-blot hybridization to detect five viruses in crude extraction of the infected leaves. And three SqMV probes of different lengths （0.55, 1.6, and 2.7 kb, respectively） were designed to investigate the effect of hybridization. The results showed that the sensitivity for detecting the crude extraction of infected leaves by ZYMV, WMV, CMV, PRSV-W, and SqMV was down to 1：160, 1：160, 1：320, 1：160, and 1：320, respectively. Three SqMV probes of different length showed no differences on the sensitivity and specificity. The digoxigenin-labelled probes prepared by PCR could be used for accurate and rapid identification of 5 viruses infecting cucurbitaceous crops with good stabilities, sensitivities, specificity, and reproducibilifies.
基金supported by the Science and Technology Commission of Shanghai Municipality (21DZ1100500)the Shanghai Municipal Science and Technology Major Project+1 种基金the Shanghai Frontiers Science Center Program (2021-2025 No.20)Shanghai Hong Kong,Macao,and Taiwan Cooperation Project (No.19490760900).
文摘The MINimal emission FLUXes(MINFLUX)technique in optical microscopy,widely recognized as the next innovative fluorescence microscopy method,claims a spatial resolution of 1-3 nm in both dead and living cells.To make use of the full resolution of the MINFLUX microscope,it is important to select appropriate fluorescence probes and labeling strategies,especially in living-cell imaging.This paper mainly focuses on recent applications and developments of fluorescence probes and the relevant labeling strategy for MINFLUX microscopy.Moreover,we discuss the deficiencies that need to be addressed in the future and a plan for the possible progression of MINFLUX to help investigators who have been involved in or are just starting in the field of super-resolution imaging microscopy with theoretical support.
基金supported by the National Natural Science Foundation of China(Grant No.61178086)Science and Technology Program of Guangzhou,China(Grant No.2012J4300138)Foundation for Distinguished Young Talents in South China Normal University,China.(Grant No.2012KJ010).
文摘We demonstrate the feasibility of simultancous multi-probe detection for an optcal-resolution photoacoustic microscopy(OR-PAM)system.OR-P AM has elicited the attention of biomedical imaging researchers because of its optical absorption contrast and high spatial resolution with great imaging depth.OR-PAM allows label-free and noninvasive imaging by maximizing the optical absorption of endogenous biomolecules.However,given the inadequate absoption of some biomolcules,detection sensitivity at the same incident intensity requires improvement.In this study,a modulated continuous wave with power density less than 3mW/cm^(2)(1/4 of the ANSI safety limit)excited the weak photoacoustic(PA)signals of biological cells.A microcavity traneducer is developed based on the bulk modulus of gas five orders of magnitude lower than that of solid;air pressure variation is inversely proportional to cavity volume at the same temperature increase.Considering that a PA wave expands in various directions,detecting PA signals from different positions and adding them together can increase detection sensitivity and signal-to-noise ratio.Therefore,we employ four detectors to acquire tiny PA signals simul-taneously.Experimental results show that the developed OR-PAM system allows the label-free imaging of cells with weak optical absorption.
基金the National Natural Science Foundation of China (296333010) and The President Science Foundation of the Chinese Academy of Scie
文摘Octadecylamine was derivatized with dansyl chloride (5-dimethylaminonaphthalene-1-sulfonyl chloride) In order to simplify and understand the LB films of fluorescent probe labeling proteins. its monolayer and multilayers in the absence and presence of stearic acid were deposited by LB technique. Fluorescence spectra and lifetimes of the fluorescent products were studied to elucidate the microenvironment of molecules in the LB films.
基金supported by the National Natural Science Foundation of China(21705102,21775096,and 22074084)the Basic Research Program of Shanxi Province(Free Exploration,20210302123430).
文摘Altered metabolism has long been recognized as a central hallmark of cancer;however,in the fluorescence imaging field,few studies have been conducted to label tumors by exploiting metabolic differences between cancer cells and normal cells.In this work,we successfully developed a metabolic probe MB-C for specific imaging of glutathione(GSH)dynamic metabolic pathways.GSH was endogenously metabolized to produce SO_(2)via Na_(2)S_(2)O_(3) and thiosulfate sulfurtransferase,equilibrating with sulfites/bisulfites.MB-C was allowed to be activated by GSH along with multi-fluorescence emission increased in red and green channels and further sequence-response metabolites(SO_(2))of GSH in significant fluorescence ratio change of red and green channels.Furthermore,such evident fluorescence ratio changes could be used to distinguish cancer cells from normal cells and identify tumor and normal tissues.Therefore,GSH metabolic imaging was successfully applied to accurately label tumors,which provides a new idea and practical case for the precise visualization of malignant tumors.
基金supports from the National Natural Science Foundation of China (Nos. 21422606 and 21502189)Dalian Cultivation Fund for Distinguished Young Scholars (Nos. 2014J11JH130 and 2015J12JH205)
文摘Protein labeling by using a protein tag and tag-specific fluorescent probes is increasingly becoming a useful technique for the real-time imaging of proteins in living cells. SNAP-tag as one of the most prominent fusion tags has been widely used and already commercially available. Recently, various fluorogenic probes for SNAP-tag based protein labeling were reported. Owing to turn-on fluorescence response, fluorogenic probes for SNAP-tag minimize the fluorescence background caused by unreacted or nonspecifically bound probes and allow for direct imaging in living cells without wash-out steps. Thus,real-time analysis of protein localization, dynamics and interactions has been made possible by SNAP-tag fluorogenic probes. In this review,we describe the design strategies of fluorogenic probes for SNAP-tag and their applications in cellular protein labeling.
文摘In this study,the DNA probe pPF14 was nonradioactively labelled by sulfo-modifica-tion,and used in a dot blot hybridization assay for detection of P.falciparum.The resultsshowed that the sulfoprobe successfully detected 25pg purified DNA and 0.001% parasitemia ofcultured P.falciparum,and did not react with human leukocyte DNA.In the study of 179clinical blood samples of malaria patients from Yunnan province,the DNA probe results corre-lated well with blood smear ones.Of 107 P.falciparum samples determined by microscope ex-amination,99 were positive by sulfoprobe (92.5%);Of 72 P.vivax samples,1 was crosslyreacted;no cross reactions were found with any of 48 normal blood samples.It is indicated thatsulfoprobe may be useful in specific diagnosis and epidemiological investigation of P.falciparuminfection.
文摘Objective To explore if strand breaks of DNA in human early chorionic villus cells in uterus were induced by diagnostic ultrasound and to evaluate the method used for detection of single-stranded breaks and double-stranded breaks in human DNA. Methods 60 normal pregnant women aged 20-30, who underwent artificial abortion during 6-8 weeks of gestation, were randomly divided into 2 experimental groups: All 30 cases were exposed to diagnostic ultrasound in uterus for 10 minutes, and 24 hours later chorionic villi were extracted; the other 30 cases were taken as the control group. Single-stranded DNA and double-stranded DNA in villus cells in all cases were isolated by the alkaline unwinding combined with hydroxylapatite chromatography, and were quantitatively detected using 32 P-labeled Alu probe for dot-blotting hybridization. Results There was no significant difference in quantity and percentage in single-stranded DNA and double-stranded DNA between 2 groups (P>0.05). 32 P-Alu probe could only hybridize with human DNA, and could detect DNA isolated from as few as 2.5×10 3 chorionic villus cells and 0.45ng DNA in human leukocytes. Conclusion The results suggested that there were no DNA strand damages in human chorionic villus cells when the uterus was exposed to diagnostic ultrasound for 10 minutes. The method,^(32)P-Alu probe for dot-blotting hybridization, was even more specific, sensitive and accurate than conventional approaches.
基金supported by grants from the National Natural Science Foundation of China (92253202 and 22177087 to X.W.)the Ministry of Science and Technology (2023YFC3402200)the Fundamental Research Funds for the Central Universities (2042023kfyq05).
文摘As a cornerstone of the central dogma of molecular biology,RNA plays vital roles in living organisms.Over the past few decades,many RNA labeling technologies have been developed to elucidate the biological function of RNA.These technologies have signifi-cantly advanced our understanding of RNA secondary structure,localization,and turnover.Additionally,taking advantage of these innovative RNA labeling approaches,plenty of tool kits have been devised for the regulation of RNA-related biological process,such as gene expression and gene editing.In this review,we primarily focus on an array of intracellular RNA labeling methods,encom-passing chemical probes-based labeling,metabolic labeling,and proximity-dependent labeling.We also provide a brief overview of their applications in the research of RNA biology.Finally,the perspectives of RNA labeling are also discussed.
文摘The synthesis of a novel long-wavelength fluorescent probe, 3-epoxypropoxy fluorescein, and its properties for labeling of histidine are briefly described in this communication. The probe is highly selective for histidine, and other amino acids with a concentration of 1 000 times higher than that of histidine did not show noticeable interferences. As an application of this probe, fluorescent labeling of histidine in human serum was attempted and the obtained results were in agreement with those given by using histidine-nickel complex adsorptive voltammetry, both of which were within the normal range of the results reported in literatures.
