Objective To establish a loop-mediated isothermal amplification( LAMP) method for detecting diarrhea pathogens( Shigella and Salmonella) in rhesus monkeys and evaluate the application of the LAMP method for detecting ...Objective To establish a loop-mediated isothermal amplification( LAMP) method for detecting diarrhea pathogens( Shigella and Salmonella) in rhesus monkeys and evaluate the application of the LAMP method for detecting bacterial diseases in nonhuman primate laboratory animals. Materials and Methods A total of 205 fecal samples of rhesus monkeys were detected in this LAMP assay. The specificity and sensitivity of LAMP for Shigella and Salmonella were analyzed,and real-time polymerase chain reaction( REAL-TIME PCR) assay was employed as control. Results The LAMP method established here needed only 45 min to complete the reaction at 63℃. Its detection limit was 10 pg / μL and with a high specificity. The positive rate of Shigella and Salmonella was 1. 5% and 6. 3%,respectively. Conclusions Here we have established a fast and simple Shigella and Salmonella LAMP detection method that has strong specificity and high sensitivity and is suitable for rapid detection of bacterial disease in macaques. The development of this rapid detection kit is underway,and it will be helpful to the diarrhea detection.展开更多
When the loop-mediated isothermal amplification(LAMP)assay is used for detecting target genes,DNA extraction is unnecessary in many cases.Simple pretreatment(e.g.heating)is enough to obtain rather sensitive responses....When the loop-mediated isothermal amplification(LAMP)assay is used for detecting target genes,DNA extraction is unnecessary in many cases.Simple pretreatment(e.g.heating)is enough to obtain rather sensitive responses.Even test samples without any pretreatment can be used as template.This feature suggests that LAMP is superior to PCR in developing point-of-care test strategies.In this study,using Stx1 gene from E.coli as model,we verified that viable cells,dead cells and extracellular DNA could function as template in the LAMP assay.In the incubation at 63℃,viable bacteria in the LAMP reaction mixture lysed completely within 2 min,providing DNA template for nucleic acid amplification.The Stx1 gene in diluted culture medium,spiked tap water,spiked seawater and real seawater all could be detected,with or without the step of DNA extraction.We found that the complex substances in real sample(e.g.natural seawater)exhibited considerable inhibitory effect on the sensitivity of the LAMP assay.These outcomes are meaningful for building a point-of-care strategy by employing the LAMP assay for environmental monitoring,bio-resource surveys,food safety,etc.in particular those based on environmental DNA.展开更多
Rice bacterial leaf brown spot disease caused by Pseudomonas syringae pv.syringae(Pss)is a major disease on rice.In recent years,Pss has emerged worldwide,seriously affecting rice production.It is very important to es...Rice bacterial leaf brown spot disease caused by Pseudomonas syringae pv.syringae(Pss)is a major disease on rice.In recent years,Pss has emerged worldwide,seriously affecting rice production.It is very important to establish a rapid detection method of Pss for the diagnosis and prevention of this disease.In order to robust and accurately diagnose the rice bacterial leaf brown spot disease in the field and laboratory,an assay system for the Pss was developed in this study,and the specific sequence of hrcN was used as the target,based on loop-mediated isothermal amplification(LAMP).The best detection system was MgSO 48 mmol·L^(-1),Bst DNA polymerase 8 U,dNTP 1.4 mmol·L^(-1),the ratio of internal and outer primers was 2:1,the reaction temperature was 63℃,the reaction time was 45 min,and the lowest sensitivity was 104 CFU·mL^(-1).This results provided an accurate and robust method for laboratory and field diagnosis of bacterial leaf brown spot disease of rice.展开更多
目的为快速检测微小隐孢子虫,建立并优化了以SYBR Green I显色的环介导等温扩增快速检测隐孢子虫的方法。方法根据微小隐孢子虫18SrRNA基因的4条特异LAMP引物,设计2条环引物,建立了微小隐孢子虫LAMP检测方法。结果该方法省去95℃热变性...目的为快速检测微小隐孢子虫,建立并优化了以SYBR Green I显色的环介导等温扩增快速检测隐孢子虫的方法。方法根据微小隐孢子虫18SrRNA基因的4条特异LAMP引物,设计2条环引物,建立了微小隐孢子虫LAMP检测方法。结果该方法省去95℃热变性和80℃酶失活过程,其最佳反应温度和时间是63℃和60min,Betaine、MgSO4、dNTP Mixture、Bst DNA聚合酶大片段的最佳浓度分别是0.8mol/L、8mmol/L、0.8mmol/L、8U/25μL,内外引物浓度分别为1.2μmol/L、0.2μmol/L,添加环引物后体系反应时间缩短为20min。对贾第虫、肠阿米巴、柔嫩艾美耳球虫、类圆线虫检测为阴性。该方法简便、快速,无需特殊设备。结论和常规PCR方法比较,LAMP检测隐孢子虫的灵敏度提高了100倍。该方法的建立为野外和临床隐孢子虫的快速检测提供技术手段。展开更多
文摘Objective To establish a loop-mediated isothermal amplification( LAMP) method for detecting diarrhea pathogens( Shigella and Salmonella) in rhesus monkeys and evaluate the application of the LAMP method for detecting bacterial diseases in nonhuman primate laboratory animals. Materials and Methods A total of 205 fecal samples of rhesus monkeys were detected in this LAMP assay. The specificity and sensitivity of LAMP for Shigella and Salmonella were analyzed,and real-time polymerase chain reaction( REAL-TIME PCR) assay was employed as control. Results The LAMP method established here needed only 45 min to complete the reaction at 63℃. Its detection limit was 10 pg / μL and with a high specificity. The positive rate of Shigella and Salmonella was 1. 5% and 6. 3%,respectively. Conclusions Here we have established a fast and simple Shigella and Salmonella LAMP detection method that has strong specificity and high sensitivity and is suitable for rapid detection of bacterial disease in macaques. The development of this rapid detection kit is underway,and it will be helpful to the diarrhea detection.
文摘When the loop-mediated isothermal amplification(LAMP)assay is used for detecting target genes,DNA extraction is unnecessary in many cases.Simple pretreatment(e.g.heating)is enough to obtain rather sensitive responses.Even test samples without any pretreatment can be used as template.This feature suggests that LAMP is superior to PCR in developing point-of-care test strategies.In this study,using Stx1 gene from E.coli as model,we verified that viable cells,dead cells and extracellular DNA could function as template in the LAMP assay.In the incubation at 63℃,viable bacteria in the LAMP reaction mixture lysed completely within 2 min,providing DNA template for nucleic acid amplification.The Stx1 gene in diluted culture medium,spiked tap water,spiked seawater and real seawater all could be detected,with or without the step of DNA extraction.We found that the complex substances in real sample(e.g.natural seawater)exhibited considerable inhibitory effect on the sensitivity of the LAMP assay.These outcomes are meaningful for building a point-of-care strategy by employing the LAMP assay for environmental monitoring,bio-resource surveys,food safety,etc.in particular those based on environmental DNA.
基金Supported by the Natural Science Foundation of Heilongjiang Province(Topic C2017032)Heilongjiang Province Applied Technology Research and Development Program(Topic GA19B104)the National Key Research and Development Program(Topic 2018YFD0300105)。
文摘Rice bacterial leaf brown spot disease caused by Pseudomonas syringae pv.syringae(Pss)is a major disease on rice.In recent years,Pss has emerged worldwide,seriously affecting rice production.It is very important to establish a rapid detection method of Pss for the diagnosis and prevention of this disease.In order to robust and accurately diagnose the rice bacterial leaf brown spot disease in the field and laboratory,an assay system for the Pss was developed in this study,and the specific sequence of hrcN was used as the target,based on loop-mediated isothermal amplification(LAMP).The best detection system was MgSO 48 mmol·L^(-1),Bst DNA polymerase 8 U,dNTP 1.4 mmol·L^(-1),the ratio of internal and outer primers was 2:1,the reaction temperature was 63℃,the reaction time was 45 min,and the lowest sensitivity was 104 CFU·mL^(-1).This results provided an accurate and robust method for laboratory and field diagnosis of bacterial leaf brown spot disease of rice.
文摘目的为快速检测微小隐孢子虫,建立并优化了以SYBR Green I显色的环介导等温扩增快速检测隐孢子虫的方法。方法根据微小隐孢子虫18SrRNA基因的4条特异LAMP引物,设计2条环引物,建立了微小隐孢子虫LAMP检测方法。结果该方法省去95℃热变性和80℃酶失活过程,其最佳反应温度和时间是63℃和60min,Betaine、MgSO4、dNTP Mixture、Bst DNA聚合酶大片段的最佳浓度分别是0.8mol/L、8mmol/L、0.8mmol/L、8U/25μL,内外引物浓度分别为1.2μmol/L、0.2μmol/L,添加环引物后体系反应时间缩短为20min。对贾第虫、肠阿米巴、柔嫩艾美耳球虫、类圆线虫检测为阴性。该方法简便、快速,无需特殊设备。结论和常规PCR方法比较,LAMP检测隐孢子虫的灵敏度提高了100倍。该方法的建立为野外和临床隐孢子虫的快速检测提供技术手段。
