Viral diseases represent one of the major threats for salmonids aquaculture.Early detection and identification of viral pathogens is the main prerequisite prior to undertaking effective prevention and control measures...Viral diseases represent one of the major threats for salmonids aquaculture.Early detection and identification of viral pathogens is the main prerequisite prior to undertaking effective prevention and control measures.Rapid,sensitive,efficient and portable detection method is highly essential for fish viral diseases detection.Biosensor strategies are highly prevalent and fulfill the expanding demands of on-site detection with fast response,cost-effectiveness,high sensitivity,and selectivity.With the development of material science,the nucleic acid biosensors fabricated by semiconductor have shown great potential in rapid and early detection or screening for diseases at salmonids fisheries.This paper reviews the current detection development of salmonids viral diseases.The present limitations and challenges of salmonids virus diseases surveillance and early detection are presented.Novel nucleic acid semiconductor biosensors are briefly reviewed.The perspective and potential application of biosensors in the on-site detection of salmonids diseases are discussed.展开更多
Enterocytozoon hepatopenaei(EHP)infection has seriously affected prawn culture globally.The symptoms of the infection are not apparent,and traditional detection methods are time consuming and low in accuracy.We develo...Enterocytozoon hepatopenaei(EHP)infection has seriously affected prawn culture globally.The symptoms of the infection are not apparent,and traditional detection methods are time consuming and low in accuracy.We developed a new onsite rapid testing device(size 18.8×16.7×6.6 cm^(3))for EHP based on magnesium pyrophosphate precipitation and facilitated by loop mediated isothermal amplification(LAMP).The design and fabrication of the device enables efficient light absorbance.The device has a highly sensitive detector,high-precision thermal controller,and humanized touch screen.The temperature control precision of the device is 0.2-0.3℃ at 60℃,63℃,and 65℃.The coefficients of variation values(CVV)of the luminous power in one channel at light on and off were found to be 0.0097 and 0.0014,respectively,within 1 h.The CVV of the background,luminous power,and values of eight PCR tubes filled with pure water were all less than 5%.In the EHP experiment,eight samples(including seven positive and one negative)confirmed the effectiveness of the device,and four positive and four negative samples verified whether cross-contamination exists.Among them,the rise time of the curve was about 15 min.These results assert that the developed device exhibits enhanced stability and uniformity and has excellent performance with high sensitivity,good specificity,and low testing time.Moreover,the optimal and minimum absorbance range was 555-655 nm for monitoring the production of LAMP.展开更多
The outbreak of virus-induced infectious diseases poses a global public-health challenge.Nucleic acid amplification testing(NAAT)enables early detection of pandemic viruses and plays a vital role in preventing onward ...The outbreak of virus-induced infectious diseases poses a global public-health challenge.Nucleic acid amplification testing(NAAT)enables early detection of pandemic viruses and plays a vital role in preventing onward transmission.However,the requirement of skilled operators,expensive instrumentation,and biosafety laboratories has hindered the use of NAAT for screening and diagnosis of suspected patients.Here we report development of a fully automated centrifugal microfluidic system with sample-in-answer-out capability for sensitive,specific,and rapid viral nucleic acid testing.The release of nucleic acids and the subsequent reverse transcription loop-mediated isothermal amplification(RT-LAMP)were integrated into the reaction units of a microfluidic disc.The whole processing steps such as injection of reagents,fluid actuation by rotation,heating and temperature control,and detection of fluorescence signals were carried out automatically by a customized instrument.We validate the centrifugal microfluidic system using oropharyngeal swab samples spiked with severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)armored RNA particles.The estimated limit of detection for armored RNA particles is 2 copies per reaction,the throughput is 21 reactions per disc,and the assay sample-to-answer time is approximately 70 min.This enclosed and automated microfluidic system efficiently avoids viral contamination of aerosol,and can be readily adapted for virus detection outside the diagnostic laboratory.展开更多
Point-of-care nucleic acid testing(POCNAT) has played an important role in the outbreak of infectious diseases(e.g., COVID-19) over recent years. POCNAT aims to realize the rapid, simple and automatic detection of nuc...Point-of-care nucleic acid testing(POCNAT) has played an important role in the outbreak of infectious diseases(e.g., COVID-19) over recent years. POCNAT aims to realize the rapid, simple and automatic detection of nucleic acid. Thanks to the development of manufacturing technology, electronic information technology, artificial intelligence technology, and biological information technology in recent years, the development of the POCNAT device has led to significant advancement. Instead of the normal nucleic acid detection methods used in the laboratory, some novel experimental carriers have been applied, such as chips, cartridges and papers. The application of these experimental carriers has realized the automation and integration of nucleic acid detection. The entire process of nucleic acid detection is normally divided into three steps(nucleic acid extraction, target amplification and signal detection). All of the reagents required by the process can be pre-stored on these experimental carriers, without unnecessary manual operation. Furthermore, all of the processes are carried out in this experimental carrier, with the assistance of a specific control device. Although they are complicated to manufacture and precise in design,their application provides a significant step forwards in nucleic acid detection and realizes the integration of nucleic acid detection. This technology has great potential in the field of point-of-care molecular diagnostics in the future. This paper focuses on the relevant content of these experimental carriers.展开更多
Screening tests for blood donations are based upon sensitivity, cost-effectiveness and their suitability for high-throughput testing. Enzyme immunoassay (EIAs) for hepatitis C virus (HCV) antibodies were the initial s...Screening tests for blood donations are based upon sensitivity, cost-effectiveness and their suitability for high-throughput testing. Enzyme immunoassay (EIAs) for hepatitis C virus (HCV) antibodies were the initial screening tests introduced. The ”first generation“ antibody EIAs detected seroconversion after unduly long infectious window period. Improved HCV antibody assays still had an infectious window period around 66 d. HCV core antigen EIAs shortened the window period considerably, but high costs did not lead to widespread acceptance. A fourth-generation HCV antigen and antibody assay (combination EIA) is more convenient as two infectious markers of HCV are detected in the same assay. Molecular testing for HCV-RNA utilizing nucleic acid amplification technology (NAT) is the most sensitive assay and shortens the window period to only 4 d. Implementation of NAT in many developed countries around the world has resulted in dramatic reductions in transfusion transmissible HCV and relative risk is now < 1 per million donations. However, HCV serology still continues to be retained as some donations are serology positive but NAT negative. In resource constrained countries HCV screening is highly variable, depending upon infrastructure, trained manpower and financial resource. Rapid tests which do not require instrumentation and are simple to perform are used in many small and remotely located blood centres. The sensitivity as compared to EIAs is less and wherever feasible HCV antibody EIAs are most frequently used screening assays. Efforts have been made to implement combined antigen-antibody assays and even NAT in some of these countries.展开更多
Background:In a few discharged patients with coronavirus disease 2019(COVID-19),the nucleic acid test shows positive results again.Whether this is due to relapse of the disease,reinfection by the virus,or a false-posi...Background:In a few discharged patients with coronavirus disease 2019(COVID-19),the nucleic acid test shows positive results again.Whether this is due to relapse of the disease,reinfection by the virus,or a false-positive result at hospital discharge is worth exploring.Case presentation:A woman with COVID-19 was discharged from the hospital after integrative treatment with traditional Chinese and Western medicine because she met the discharge standards.However,she obtained positive results on a nucleic acid test 22 days later.Conclusion:Based on this positive test result in a discharged patient with COVID-19,anal tests and coronavirus antibody tests should be combined with throat swab tests to further develop the diagnosis and discharge standards for patients with COVID-19.展开更多
Nucleic acid amplification tests(NAAT)have long been used in laboratory facilities and recently revolutionized the field of molecular diagnostics in point-of-care testing.Digital microfluidics(DMF)has emerged as a pro...Nucleic acid amplification tests(NAAT)have long been used in laboratory facilities and recently revolutionized the field of molecular diagnostics in point-of-care testing.Digital microfluidics(DMF)has emerged as a promising tool to complete the entire NAAT workflow in a miniaturized format with minimum human intervention.Based on electric fields to manipulate independent reaction droplets,the compact DMF system could perform multiple processes simultaneously and automatically in a programmable fashion.This combination is beginning to establish powerful sample-to-answer platforms in remote or resource-limited settings.Herein,we provide a comprehensive overview of the state-of-the-art DMF technology for point-of-care NAAT.This review focused on key principles of DMF platforms and the latest trends in system integration for automated processes of nucleic acid extraction,amplification,and detection.Also,this article discusses current challenges,including control systems,scalability and throughput,as well as future prospects of DMF-based NAAT strategy for the next generation of point-of-care diagnostics.展开更多
HIV-indeterminate Western blotting(WB)results are typically obtained in WB confirmatory assays,and the number of indeterminate samples may increase with the detection of HIV infections,which will present considerable ...HIV-indeterminate Western blotting(WB)results are typically obtained in WB confirmatory assays,and the number of indeterminate samples may increase with the detection of HIV infections,which will present considerable challenges for the management of HIV/AIDS.Nucleic acid detection has been used as a laboratory test for screening suspected or indeterminate samples.However,the effectiveness of these assays for the differential diagnosis of HIV-indeterminate WB samples remained undetermined.In this study,210 subjects with HIV-indeterminate WB results were detected from 6360 positive HIV screening samples between 2015 and 2016 in southeastern China,in which HIV-indeterminate WB results accounted for 3.30%.The highest proportion of indeterminate results was observed in pregnant and lying-in women receiving physical examinations(16.67%),followed by that in voluntary blood donors(8.82%).The most common WB band patterns were p24,gpl60 and p24,and gpl60.The follow-up study revealed that the highest negative and positive conversion rates of HIV antibodies were in samples with a single p24 band(80.28%),and with gpl60 and p24 bands(86.21%),respectively.Among the Env,Gag,and Pol antibodies,samples with a Gag band showed the highest negative conversion rate(81.25%),whereas the highest positive conversion rate was observed in samples with an Env band(56.76%).In addition,quantitative and qualitative HIV nucleic acid testing exhibited the highest sensitivity(96.3%)and specificity(97.85%),respectively.Our results indicate a lower proportion of HIV indeterminate WB results in southeastern China compared to previous reports,and the follow-up re-examination of patients with HIV indeterminate results should be performed.Nucleic acid testing facilitates the identification of HIV infections.展开更多
基金supported by the National Key Research and Development Program of China(2022YFC2601304)National Key Research and Development Program of China(2022YFC2602100)。
文摘Viral diseases represent one of the major threats for salmonids aquaculture.Early detection and identification of viral pathogens is the main prerequisite prior to undertaking effective prevention and control measures.Rapid,sensitive,efficient and portable detection method is highly essential for fish viral diseases detection.Biosensor strategies are highly prevalent and fulfill the expanding demands of on-site detection with fast response,cost-effectiveness,high sensitivity,and selectivity.With the development of material science,the nucleic acid biosensors fabricated by semiconductor have shown great potential in rapid and early detection or screening for diseases at salmonids fisheries.This paper reviews the current detection development of salmonids viral diseases.The present limitations and challenges of salmonids virus diseases surveillance and early detection are presented.Novel nucleic acid semiconductor biosensors are briefly reviewed.The perspective and potential application of biosensors in the on-site detection of salmonids diseases are discussed.
基金supported by the grant from the National Natural Science Foundation of China(Nos.61901168,61971187,61871180,82002405)Hunan Key Research and Development Program(No.2021SK2003)+1 种基金Zhuzhou Innovative City Construction Project(No.2020-020)China Postdoctoral Science Foundation(No.2018M630498)。
文摘Enterocytozoon hepatopenaei(EHP)infection has seriously affected prawn culture globally.The symptoms of the infection are not apparent,and traditional detection methods are time consuming and low in accuracy.We developed a new onsite rapid testing device(size 18.8×16.7×6.6 cm^(3))for EHP based on magnesium pyrophosphate precipitation and facilitated by loop mediated isothermal amplification(LAMP).The design and fabrication of the device enables efficient light absorbance.The device has a highly sensitive detector,high-precision thermal controller,and humanized touch screen.The temperature control precision of the device is 0.2-0.3℃ at 60℃,63℃,and 65℃.The coefficients of variation values(CVV)of the luminous power in one channel at light on and off were found to be 0.0097 and 0.0014,respectively,within 1 h.The CVV of the background,luminous power,and values of eight PCR tubes filled with pure water were all less than 5%.In the EHP experiment,eight samples(including seven positive and one negative)confirmed the effectiveness of the device,and four positive and four negative samples verified whether cross-contamination exists.Among them,the rise time of the curve was about 15 min.These results assert that the developed device exhibits enhanced stability and uniformity and has excellent performance with high sensitivity,good specificity,and low testing time.Moreover,the optimal and minimum absorbance range was 555-655 nm for monitoring the production of LAMP.
基金supported by the National Natural Science Foundation of China(91959101,21904028)Chinese Academy of Sciences(YJKYYQ20180055,YJKYYQ20190068,ZDBS-LY-SLH025)the Strategic Priority Research Program of Chinese Academy of Sciences(XDB36000000)。
文摘The outbreak of virus-induced infectious diseases poses a global public-health challenge.Nucleic acid amplification testing(NAAT)enables early detection of pandemic viruses and plays a vital role in preventing onward transmission.However,the requirement of skilled operators,expensive instrumentation,and biosafety laboratories has hindered the use of NAAT for screening and diagnosis of suspected patients.Here we report development of a fully automated centrifugal microfluidic system with sample-in-answer-out capability for sensitive,specific,and rapid viral nucleic acid testing.The release of nucleic acids and the subsequent reverse transcription loop-mediated isothermal amplification(RT-LAMP)were integrated into the reaction units of a microfluidic disc.The whole processing steps such as injection of reagents,fluid actuation by rotation,heating and temperature control,and detection of fluorescence signals were carried out automatically by a customized instrument.We validate the centrifugal microfluidic system using oropharyngeal swab samples spiked with severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)armored RNA particles.The estimated limit of detection for armored RNA particles is 2 copies per reaction,the throughput is 21 reactions per disc,and the assay sample-to-answer time is approximately 70 min.This enclosed and automated microfluidic system efficiently avoids viral contamination of aerosol,and can be readily adapted for virus detection outside the diagnostic laboratory.
基金supported by the National Natural Science Foundation of China (Nos. 61901168, 61971187, 61871180, 61571187, 81902153)Zhuzhou Innovative City Construction Project (No. 2020-020)+2 种基金China Postdoctoral Science Foundation (No. 2018M630498)Hunan Urgency Project (No. 2020SK3005)Education Department Outstanding Young Project of Hunan Province (No. 18B299)。
文摘Point-of-care nucleic acid testing(POCNAT) has played an important role in the outbreak of infectious diseases(e.g., COVID-19) over recent years. POCNAT aims to realize the rapid, simple and automatic detection of nucleic acid. Thanks to the development of manufacturing technology, electronic information technology, artificial intelligence technology, and biological information technology in recent years, the development of the POCNAT device has led to significant advancement. Instead of the normal nucleic acid detection methods used in the laboratory, some novel experimental carriers have been applied, such as chips, cartridges and papers. The application of these experimental carriers has realized the automation and integration of nucleic acid detection. The entire process of nucleic acid detection is normally divided into three steps(nucleic acid extraction, target amplification and signal detection). All of the reagents required by the process can be pre-stored on these experimental carriers, without unnecessary manual operation. Furthermore, all of the processes are carried out in this experimental carrier, with the assistance of a specific control device. Although they are complicated to manufacture and precise in design,their application provides a significant step forwards in nucleic acid detection and realizes the integration of nucleic acid detection. This technology has great potential in the field of point-of-care molecular diagnostics in the future. This paper focuses on the relevant content of these experimental carriers.
文摘Screening tests for blood donations are based upon sensitivity, cost-effectiveness and their suitability for high-throughput testing. Enzyme immunoassay (EIAs) for hepatitis C virus (HCV) antibodies were the initial screening tests introduced. The ”first generation“ antibody EIAs detected seroconversion after unduly long infectious window period. Improved HCV antibody assays still had an infectious window period around 66 d. HCV core antigen EIAs shortened the window period considerably, but high costs did not lead to widespread acceptance. A fourth-generation HCV antigen and antibody assay (combination EIA) is more convenient as two infectious markers of HCV are detected in the same assay. Molecular testing for HCV-RNA utilizing nucleic acid amplification technology (NAT) is the most sensitive assay and shortens the window period to only 4 d. Implementation of NAT in many developed countries around the world has resulted in dramatic reductions in transfusion transmissible HCV and relative risk is now < 1 per million donations. However, HCV serology still continues to be retained as some donations are serology positive but NAT negative. In resource constrained countries HCV screening is highly variable, depending upon infrastructure, trained manpower and financial resource. Rapid tests which do not require instrumentation and are simple to perform are used in many small and remotely located blood centres. The sensitivity as compared to EIAs is less and wherever feasible HCV antibody EIAs are most frequently used screening assays. Efforts have been made to implement combined antigen-antibody assays and even NAT in some of these countries.
文摘Background:In a few discharged patients with coronavirus disease 2019(COVID-19),the nucleic acid test shows positive results again.Whether this is due to relapse of the disease,reinfection by the virus,or a false-positive result at hospital discharge is worth exploring.Case presentation:A woman with COVID-19 was discharged from the hospital after integrative treatment with traditional Chinese and Western medicine because she met the discharge standards.However,she obtained positive results on a nucleic acid test 22 days later.Conclusion:Based on this positive test result in a discharged patient with COVID-19,anal tests and coronavirus antibody tests should be combined with throat swab tests to further develop the diagnosis and discharge standards for patients with COVID-19.
基金support from The Ivan Bowen Family Foundation and the Department of Physiology and Biomedical Engineering at Mayo Clinic,Rochester MN.
文摘Nucleic acid amplification tests(NAAT)have long been used in laboratory facilities and recently revolutionized the field of molecular diagnostics in point-of-care testing.Digital microfluidics(DMF)has emerged as a promising tool to complete the entire NAAT workflow in a miniaturized format with minimum human intervention.Based on electric fields to manipulate independent reaction droplets,the compact DMF system could perform multiple processes simultaneously and automatically in a programmable fashion.This combination is beginning to establish powerful sample-to-answer platforms in remote or resource-limited settings.Herein,we provide a comprehensive overview of the state-of-the-art DMF technology for point-of-care NAAT.This review focused on key principles of DMF platforms and the latest trends in system integration for automated processes of nucleic acid extraction,amplification,and detection.Also,this article discusses current challenges,including control systems,scalability and throughput,as well as future prospects of DMF-based NAAT strategy for the next generation of point-of-care diagnostics.
基金supported by grants from the Cultivation of Young Talents Project Fund from the Fujian Provincial Health and Family Planning Commission (Grant No. 2015-ZQN-ZD11)the Pilot Project of Fujian Provincial Department of Science and Technology (Grant No. 2016Y0010)+2 种基金the Jiangsu Provincial Project of Invigorating Health Care through Science, Technology and EducationJiangsu Provincial Medical Youth Talentthe Project of Invigorating Health Care through Science, Technology and Education (Grant No. QNRC2016621)
文摘HIV-indeterminate Western blotting(WB)results are typically obtained in WB confirmatory assays,and the number of indeterminate samples may increase with the detection of HIV infections,which will present considerable challenges for the management of HIV/AIDS.Nucleic acid detection has been used as a laboratory test for screening suspected or indeterminate samples.However,the effectiveness of these assays for the differential diagnosis of HIV-indeterminate WB samples remained undetermined.In this study,210 subjects with HIV-indeterminate WB results were detected from 6360 positive HIV screening samples between 2015 and 2016 in southeastern China,in which HIV-indeterminate WB results accounted for 3.30%.The highest proportion of indeterminate results was observed in pregnant and lying-in women receiving physical examinations(16.67%),followed by that in voluntary blood donors(8.82%).The most common WB band patterns were p24,gpl60 and p24,and gpl60.The follow-up study revealed that the highest negative and positive conversion rates of HIV antibodies were in samples with a single p24 band(80.28%),and with gpl60 and p24 bands(86.21%),respectively.Among the Env,Gag,and Pol antibodies,samples with a Gag band showed the highest negative conversion rate(81.25%),whereas the highest positive conversion rate was observed in samples with an Env band(56.76%).In addition,quantitative and qualitative HIV nucleic acid testing exhibited the highest sensitivity(96.3%)and specificity(97.85%),respectively.Our results indicate a lower proportion of HIV indeterminate WB results in southeastern China compared to previous reports,and the follow-up re-examination of patients with HIV indeterminate results should be performed.Nucleic acid testing facilitates the identification of HIV infections.
