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
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 Rapid molecular testing has revolutionized the management of suspected viral meningitis and encephalitis by providing an etiological diagnosis in<90 min with potential to improve outcomes and shorten inp...BACKGROUND Rapid molecular testing has revolutionized the management of suspected viral meningitis and encephalitis by providing an etiological diagnosis in<90 min with potential to improve outcomes and shorten inpatient stays.However,use of molecular assays can vary widely.AIM To evaluate current practice for molecular testing of pediatric cerebrospinal fluid(CSF)samples across the United Kingdom using a structured questionnaire.METHODS A structured telephone questionnaire survey was conducted between July and August 2020.Data was collected on the availability of viral CSF nucleic acid amplification testing(NAAT),criteria used for testing and turnaround times including the impact of the coronavirus disease 2019 pandemic.RESULTS Of 196/212(92%)microbiology laboratories responded;63/196(32%)were excluded from final analysis as they had no on-site microbiology laboratory and outsourced their samples.Of 133 Laboratories included in the study,47/133(35%)had onsite facilities for viral CSF NAAT.Hospitals currently undertaking onsite NAAT(n=47)had much faster turnaround times with 39 centers(83%)providing results in≤24 h as compared to those referring samples to neighboring laboratories(5/86;6%).CONCLUSION Onsite/near-patient rapid NAAT(including polymerase chain reaction)is recommended wherever possible to optimize patient management in the acute setting.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
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
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
The pandemic caused by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)has led to unprecedented social and economic disruption.Many nucleic acid testing(NAT)laboratories in China have been established to co...The pandemic caused by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)has led to unprecedented social and economic disruption.Many nucleic acid testing(NAT)laboratories in China have been established to control the epidemic better.This proficiency testing(PT)aims to evaluate the participants’performance in qualitative and quantitative SARS-CoV-2 NAT and to explore the factors that contribute to differences in detection capabilities.Two different concentrations of RNA samples(A,B)were used for quantitative PT.Pseudovirus samples D,E(different concentrations)and negative sample(F)were used for qualitative PT.50 data sets were reported for qualitative PT,of which 74.00%were entirely correct for all samples.Fortytwo laboratories participated in the quantitative PT.37 submitted all gene results,of which only 56.76%were satisfactory.For qualitative detection,it is suggested that laboratories should strengthen personnel training,select qualified detection kits,and reduce cross-contamination to improve detection accuracy.For quantitative detection,the results of the reverse transcription digital PCR(RT-dPCR)method were more comparable and reliable than those of reverse transcription quantitative PCR(RT-qPCR).The copy number concentration of ORF1ab and N in samples A and B scattered in 85,223,50,and 106 folds,respectively.The differences in the quantitative result of RT-qPCR was mainly caused by the non-standard use of reference materials and the lack of personnel operating skills.Comparing the satisfaction of participants participating in both quantitative and qualitative proficiency testing,95.65%of the laboratories with satisfactory quantitative results also judged the qualitative results correctly,while 85.71%of the laboratories with unsatisfactory quantitative results were also unsatisfied with their qualitative judgments.Therefore,the quantitative ability is the basis of qualitative judgment.Overall,participants from hospitals reported more satisfactory results than those from enterprises and universities.Therefore,surveillance,daily qualitiy control and standardized operating procedures should be strengthened to improve the capability of SARS-CoV-2 NAT.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
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.
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 Rapid molecular testing has revolutionized the management of suspected viral meningitis and encephalitis by providing an etiological diagnosis in<90 min with potential to improve outcomes and shorten inpatient stays.However,use of molecular assays can vary widely.AIM To evaluate current practice for molecular testing of pediatric cerebrospinal fluid(CSF)samples across the United Kingdom using a structured questionnaire.METHODS A structured telephone questionnaire survey was conducted between July and August 2020.Data was collected on the availability of viral CSF nucleic acid amplification testing(NAAT),criteria used for testing and turnaround times including the impact of the coronavirus disease 2019 pandemic.RESULTS Of 196/212(92%)microbiology laboratories responded;63/196(32%)were excluded from final analysis as they had no on-site microbiology laboratory and outsourced their samples.Of 133 Laboratories included in the study,47/133(35%)had onsite facilities for viral CSF NAAT.Hospitals currently undertaking onsite NAAT(n=47)had much faster turnaround times with 39 centers(83%)providing results in≤24 h as compared to those referring samples to neighboring laboratories(5/86;6%).CONCLUSION Onsite/near-patient rapid NAAT(including polymerase chain reaction)is recommended wherever possible to optimize patient management in the acute setting.
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.
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.
基金NIM(National Institute of Metrology,China)(AKYZZ2126/AKYYJ2009).
文摘The pandemic caused by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)has led to unprecedented social and economic disruption.Many nucleic acid testing(NAT)laboratories in China have been established to control the epidemic better.This proficiency testing(PT)aims to evaluate the participants’performance in qualitative and quantitative SARS-CoV-2 NAT and to explore the factors that contribute to differences in detection capabilities.Two different concentrations of RNA samples(A,B)were used for quantitative PT.Pseudovirus samples D,E(different concentrations)and negative sample(F)were used for qualitative PT.50 data sets were reported for qualitative PT,of which 74.00%were entirely correct for all samples.Fortytwo laboratories participated in the quantitative PT.37 submitted all gene results,of which only 56.76%were satisfactory.For qualitative detection,it is suggested that laboratories should strengthen personnel training,select qualified detection kits,and reduce cross-contamination to improve detection accuracy.For quantitative detection,the results of the reverse transcription digital PCR(RT-dPCR)method were more comparable and reliable than those of reverse transcription quantitative PCR(RT-qPCR).The copy number concentration of ORF1ab and N in samples A and B scattered in 85,223,50,and 106 folds,respectively.The differences in the quantitative result of RT-qPCR was mainly caused by the non-standard use of reference materials and the lack of personnel operating skills.Comparing the satisfaction of participants participating in both quantitative and qualitative proficiency testing,95.65%of the laboratories with satisfactory quantitative results also judged the qualitative results correctly,while 85.71%of the laboratories with unsatisfactory quantitative results were also unsatisfied with their qualitative judgments.Therefore,the quantitative ability is the basis of qualitative judgment.Overall,participants from hospitals reported more satisfactory results than those from enterprises and universities.Therefore,surveillance,daily qualitiy control and standardized operating procedures should be strengthened to improve the capability of SARS-CoV-2 NAT.
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.
