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
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
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
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
AIM: To investigate dysfunctions in esophageal peristalsis and sensation in patients with Barrett’s esophagus following acid infusion using endoscopy-based testing.
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
Objectives:This study aimed to clarify the short-term symptoms,duration,and influencing factors in people recovering from coronavirus disease 2019(COVID-19)after China’s dynamic zero-COVID-19 policy was implemented i...Objectives:This study aimed to clarify the short-term symptoms,duration,and influencing factors in people recovering from coronavirus disease 2019(COVID-19)after China’s dynamic zero-COVID-19 policy was implemented in December 2022.Methods:We included data from a large-scale on-line survey conducted in China between January 14 and February 1,2023.Participants were individuals of all ages.Chi-squared tests and multivariate logistic regression analyses were performed to identify factors associated with different symptoms.Results:Overall,21,012 patients from seven regions of China were included in this study(female:71.22%).For most patients,the period from symptom onset to a negative nucleic acid test result was≤10 days(72.33%).The distribution of symptoms varied at different times,with respiratory(1-4 weeks)and psychocardiology(5-8 weeks)symptoms being the most common.Multivariate analysis identified male sex,no comorbidity,and living in northeast and northwest China(compared with central China)as independent factors associated with a lower risk of symptoms,while age(41-60 years)was a possible risk factor(compared with 18-40 years).Conclusions:Short-term respiratory and psychocardiology symptoms were the most common after COVID-19 recovery.Sex,age,geographical region,and comorbidities were potential influencing factors for the development of short-term symptoms.展开更多
Hepatitis C virus(HCV)infection represents a significant health problem and represents a heavy load on some countries like Egypt in which about 20%of the total population are infected.Initial infection is usually asym...Hepatitis C virus(HCV)infection represents a significant health problem and represents a heavy load on some countries like Egypt in which about 20%of the total population are infected.Initial infection is usually asymptomatic and result in chronic hepatitis that give rise to complications including cirrhosis and hepatocellular carcinoma.The management of HCV infection should not only be focus on therapy,but also to screen carrier individuals in order to prevent transmission.In the present,molecular detection and quantification of HCV genome by real time polymerase chain reaction(PCR)represent the gold standard in HCV diagnosis and plays a crucial role in the management of therapeutic regimens.However,real time PCR is a complicated approach and of limited distribution.On the other hand,isothermal DNA amplification techniques have been developed and offer molecular diagnosis of infectious dieses at point-of-care.In this review we discuss recombinase polymerase amplification technique and illustrate its diagnostic value over both PCR and other isothermal amplification techniques.展开更多
Clostridium difficile (C. difficile) is a spore-forming, toxin-producing, gram-positive anaerobic bacterium that is the principal etiologic agent of antibiotic-associated diarrhea. Infection with C. difficile (CDI) is...Clostridium difficile (C. difficile) is a spore-forming, toxin-producing, gram-positive anaerobic bacterium that is the principal etiologic agent of antibiotic-associated diarrhea. Infection with C. difficile (CDI) is characterized by diarrhea in clinical syndromes that vary from selflimited to mild or severe. Since its initial recognition as the causative agent of pseudomembranous colitis, C. difficile has spread around the world. CDI is one of the most common healthcare-associated infections and a significant cause of morbidity and mortality among older adult hospitalized patients. Due to extensive antibiotic usage, the number of CDIs has increased. Diagnosis of CDI is often difficult and has a substantial impact on the management of patients with the disease, mainly with regards to antibiotic management. The diagnosis of CDI is primarily based on the clinical signs and symptoms and is only confirmed by laboratory testing. Despite the high burden of CDI and the increasing interest in the disease, episodes of CDI are often misdiagnosed. The reasons for misdiagnosis are the lack of clinical suspicion or the use of inappropriate tests. The proper diagnosis of CDI reduces transmission, prevents inadequate or unnecessary treatments, and assures best antibiotic treatment. We review the options for the laboratory diagnosis of CDI within the settings of the most accepted guidelines for CDI diagnosis, treatment, and prevention of CDI.展开更多
The immense patient number caused by coronavirus disease 2019(COVID-19)global pandemic brings the urge for more knowledge about its immunological features,including the profile of basic immune parameters.In this study...The immense patient number caused by coronavirus disease 2019(COVID-19)global pandemic brings the urge for more knowledge about its immunological features,including the profile of basic immune parameters.In this study,eighty-eight reported COVID-19 patients in Wuhan were recruited from January to February,2020,including 32 severe/critical cases and56 mild/moderate cases.Their mean age was 56.43 years(range 17–83)and gender ratio(male/female)was 43:45.We tested SARS-CoV-2 RNA with commercial kits,investigated the level of serologic IgM and IgG antibodies against severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)using magnetic particle chemiluminescence immunoassays,and compared the results of serologic tests and nucleic acid test(NAT).Among 88 patients,95.45%were confirmed as positive by the combination of NAT and antibody test,which was significantly higher(P<0.001)than by single nucleic acid test(73.86%)or serologic test(65.91%).Then the correlation between temporal profile and the level of antibody response was analyzed.It showed that seroconversion started on day 5 after disease onset and IgG level was rose earlier than IgM.Comparison between patients with different disease severity suggested early seroconversion and high antibody titer were linked with less severe clinical symptoms.These results supported the combination of serologic testing and NAT in routine COVID-19 diagnosis and provided evidence on the temporal profile of antibody response in patients with different disease severity.展开更多
BACKGROUND The coronavirus disease 2019(COVID-19)is an emerging infectious disease caused by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2).Suspected cases accounted for a large proportion in the early st...BACKGROUND The coronavirus disease 2019(COVID-19)is an emerging infectious disease caused by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2).Suspected cases accounted for a large proportion in the early stage of the COVID-19 outbreak.The deviation of the nucleic acid test by throat swab(the current gold standard of COVID-19)caused by variation in sampling techniques and reagent kits and coupled with nonspecific clinical manifestations make confirmation of the suspected cases difficult.Proper management of the suspected cases of COVID-19 is crucial for disease control.CASE SUMMARY A 65-year-old male presented with fever,lymphopenia,and chest computed tomography(CT)images similar to COVID-19 after percutaneous coronary intervention.The patient was diagnosed as having bacterial pneumonia with cardiogenic pulmonary edema instead of COVID-19.This was based on four negative results for throat swab detection of SARS-CoV-2 nucleic acid using reverse transcriptase-polymerase chain reaction assay and one negative result for serological antibody of SARS-CoV-2 with the serological assay.Additionally,the distribution of ground-glass opacities and thickened blood vessels from the CT images differed from COVID-19 features,which further supported the exclusion of COVID-19.CONCLUSION Distinguishing COVID-19 patients from those with bacterial pneumonia with cardiogenic pulmonary edema can be difficult.Therefore,it requires serious identification.展开更多
The etiology of most cases of idiopathic bile acid malabsorption （IBAH） is unknown. In this study, a Swedish family with bile acid malabsorption in three consecutive generations was screened for mutations in the ile...The etiology of most cases of idiopathic bile acid malabsorption （IBAH） is unknown. In this study, a Swedish family with bile acid malabsorption in three consecutive generations was screened for mutations in the ileal apical sodium-bile acid cotransporter gene （ASBT; gene symbol, SLC10A2） and in the genes for several of the nuclear receptors known to be important for ASBT expression： the farnesoid X receptor （FXR） and peroxisome proliferator activated receptor alpha （PPARα）. The patients presented with a clinical history of idiopathic chronic watery diarrhea, which was responsive to cholestyramine treatment and consistent with IBAH. Bile acid absorption was determined using ^75Se-homocholic acid taurine （SeHCAT）; bile acid synthesis was estimated by measuring the plasma levels of 7α-hydroxy-4-cholesten-3-one （C4）. The ASBT, FXR, and PPARα genes in the affected and unaffected family members were analyzed using single stranded conformation polymorphism （SSCP）, denaturing HPLC, and direct sequencing. No ASBT mutations were identified and the ASBT gene did not segregate with the bile acid malabsorption phenotype. Similarly, no mutations or polymorphisms were identified in the FXR or PPARα genes associated with the bile acid malabsorption phenotype. These studies indicate that the intestinal bile acid malabsorption in these patients cannot be attributed to defects in ASBT. In the absence of apparent ileal disease, alternative explanations such as accelerated transit through the small intestine may be responsible for the IBAM.展开更多
Diagnostic testing plays a fundamental role in the mitigation and containment of coronavirus disease 2019(COVID-19),as it enables immediate quarantine of those who are infected and contagious and is essential for the ...Diagnostic testing plays a fundamental role in the mitigation and containment of coronavirus disease 2019(COVID-19),as it enables immediate quarantine of those who are infected and contagious and is essential for the epidemiological characterization of the virus and estimating the number of infected cases worldwide.Confirmation of viral infections,such as COVID-19,can be achieved through two general approaches:nucleic acid amplification tests(NAATs)or molecular tests,and serological or antibody-based tests.The genetic material of the pathogen is detected in NAAT,and in serological tests,host antibodies produced in response to the pathogen are identified.Other methods of diagnosing COVID-19 include radiological imaging of the lungs and in vitro detection of viral antigens.This review covers different approaches available to diagnosing COVID-19 by outlining their advantages and shortcomings,as well as appropriate indications for more accurate testing.展开更多
OBJECTIVE:To investigate anti-endotoxin action of four OAs reacted with endotoxin by the LAL assay with KTA.METHODS:Using a incubating kinetic tube reader and kinetic turbidimetric assay(KTA),the concentration-respons...OBJECTIVE:To investigate anti-endotoxin action of four OAs reacted with endotoxin by the LAL assay with KTA.METHODS:Using a incubating kinetic tube reader and kinetic turbidimetric assay(KTA),the concentration-response time curve of endotoxin reacted with limulus amebocyte lysate(LAL) at 37℃ were obtained and the action of four organic acids(OAs) on it were investigated.The four OAs were benzoic acid,salicylic acid,syringic acid and 2-amino-benzoic acid from Radix isatidis.Meanwhile,the temperature variation caused by endotoxin with the four OAs was studied by the rabbit pyrogen test(RPT).RESULTS:It was showed that a low concentration(1 mg/mL) of the four OAs had a little effect of anti-endotoxin,and when the concentrations of the four OAs were 30 mg/mL,the endotoxin was neutralized completely.The relationships between the concentrations of endotoxin and the OAs were all linear with correlation coefficients of greater than 0.9995,indicating that the four OAs all had strong anti-endotoxin action,while syringic acid had the strongest action among the four OAs with IC50 of 12.84 mg/mL.CONCLUSION:The investigations of KTA agreed well with the results obtained by means of RPT.展开更多
The study has shown free radical processes during modeling of Parkinson Disease (PD) with rotenone. We isolated striatum, brainstem, neocortex, cerebellum, spinal cord, thymus, heart, and liver of rats after rotenone ...The study has shown free radical processes during modeling of Parkinson Disease (PD) with rotenone. We isolated striatum, brainstem, neocortex, cerebellum, spinal cord, thymus, heart, and liver of rats after rotenone injection in the right striatum. The samples were taken on the 5th, 10th and 15th days after the injection. According to chemiluminescence data, the injection of rotenone initiates the disturbance of intensity of free radical processes in striatum at 5th day in a bilateral mode. After this until the 10th day these changes had restoring character, but after 15 days according to chemiluminescence and thio-barbituric acid test disturbance of lipid peroxide oxidation processes occurred. While superoxide dismutase activity has been changed significantly in all studied tissues, especially in the striatum and neocortex. It should be noted that during rotenone model there are no observed clinical symptoms in rats during 1 to 20 days, and the symptoms of the disease are observed approximately 28 days after the injection. This research could help diagnose PD in the early stage of its onset.展开更多
Objective: to explore the analysis and thinking of the results of two methods for unpaid blood donors in a certain area. Methods: 2000 blood samples from unpaid blood donors in a certain area were selected as the rese...Objective: to explore the analysis and thinking of the results of two methods for unpaid blood donors in a certain area. Methods: 2000 blood samples from unpaid blood donors in a certain area were selected as the research object. The detection method was two times of different manufacturers ELISA reagents (Xinchuang/Wantai/Kehua). Six people were tested (ID-NAT) for those who were negative for both times. If positive, they were split again, subject to the (Roche or Kehua reagents) test (six people). Results: the positive rate of HIV 1/HCV/HBV NAT initial screening was 0.5%. Six samples were positive by ELISA at the same time, and five samples were positive by identification, with the positive rate of identification being 83.33%. The positive blood samples for twice, once positive and once negative were classified as three retest positive samples, and the negative samples for twice were classified as one retest negative sample. The negative initial screening positive S/CO value was 13.75 ± 2.40, and the negative S/CO value was 8.06 ± 6.05;The minimum value of positive S/CO in the initial screening of positive retest is 8.07, the minimum value of negative S/CO is 10.12, the minimum value of positive S/CO in the initial screening of negative retest is 9.13, and the minimum value of negative S/CO is 1.02. Conclusion: the results of ELISA and single ID-NAT test for unpaid blood donors are significant. The two methods can improve the accuracy of blood sample test for unpaid blood donors, and can effectively ensure the safety of clinical blood transfusion treatment.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
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.
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.
文摘AIM: To investigate dysfunctions in esophageal peristalsis and sensation in patients with Barrett’s esophagus following acid infusion using endoscopy-based testing.
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funded by the Young Scientists Fund of the National Natural Science Foundation of China under 82305433,82305437.
文摘Objectives:This study aimed to clarify the short-term symptoms,duration,and influencing factors in people recovering from coronavirus disease 2019(COVID-19)after China’s dynamic zero-COVID-19 policy was implemented in December 2022.Methods:We included data from a large-scale on-line survey conducted in China between January 14 and February 1,2023.Participants were individuals of all ages.Chi-squared tests and multivariate logistic regression analyses were performed to identify factors associated with different symptoms.Results:Overall,21,012 patients from seven regions of China were included in this study(female:71.22%).For most patients,the period from symptom onset to a negative nucleic acid test result was≤10 days(72.33%).The distribution of symptoms varied at different times,with respiratory(1-4 weeks)and psychocardiology(5-8 weeks)symptoms being the most common.Multivariate analysis identified male sex,no comorbidity,and living in northeast and northwest China(compared with central China)as independent factors associated with a lower risk of symptoms,while age(41-60 years)was a possible risk factor(compared with 18-40 years).Conclusions:Short-term respiratory and psychocardiology symptoms were the most common after COVID-19 recovery.Sex,age,geographical region,and comorbidities were potential influencing factors for the development of short-term symptoms.
文摘Hepatitis C virus(HCV)infection represents a significant health problem and represents a heavy load on some countries like Egypt in which about 20%of the total population are infected.Initial infection is usually asymptomatic and result in chronic hepatitis that give rise to complications including cirrhosis and hepatocellular carcinoma.The management of HCV infection should not only be focus on therapy,but also to screen carrier individuals in order to prevent transmission.In the present,molecular detection and quantification of HCV genome by real time polymerase chain reaction(PCR)represent the gold standard in HCV diagnosis and plays a crucial role in the management of therapeutic regimens.However,real time PCR is a complicated approach and of limited distribution.On the other hand,isothermal DNA amplification techniques have been developed and offer molecular diagnosis of infectious dieses at point-of-care.In this review we discuss recombinase polymerase amplification technique and illustrate its diagnostic value over both PCR and other isothermal amplification techniques.
文摘Clostridium difficile (C. difficile) is a spore-forming, toxin-producing, gram-positive anaerobic bacterium that is the principal etiologic agent of antibiotic-associated diarrhea. Infection with C. difficile (CDI) is characterized by diarrhea in clinical syndromes that vary from selflimited to mild or severe. Since its initial recognition as the causative agent of pseudomembranous colitis, C. difficile has spread around the world. CDI is one of the most common healthcare-associated infections and a significant cause of morbidity and mortality among older adult hospitalized patients. Due to extensive antibiotic usage, the number of CDIs has increased. Diagnosis of CDI is often difficult and has a substantial impact on the management of patients with the disease, mainly with regards to antibiotic management. The diagnosis of CDI is primarily based on the clinical signs and symptoms and is only confirmed by laboratory testing. Despite the high burden of CDI and the increasing interest in the disease, episodes of CDI are often misdiagnosed. The reasons for misdiagnosis are the lack of clinical suspicion or the use of inappropriate tests. The proper diagnosis of CDI reduces transmission, prevents inadequate or unnecessary treatments, and assures best antibiotic treatment. We review the options for the laboratory diagnosis of CDI within the settings of the most accepted guidelines for CDI diagnosis, treatment, and prevention of CDI.
基金supported by the Emergency Scientific Research Project for COVID-19 from Wuhan City(Grant No.2020020101010008)。
文摘The immense patient number caused by coronavirus disease 2019(COVID-19)global pandemic brings the urge for more knowledge about its immunological features,including the profile of basic immune parameters.In this study,eighty-eight reported COVID-19 patients in Wuhan were recruited from January to February,2020,including 32 severe/critical cases and56 mild/moderate cases.Their mean age was 56.43 years(range 17–83)and gender ratio(male/female)was 43:45.We tested SARS-CoV-2 RNA with commercial kits,investigated the level of serologic IgM and IgG antibodies against severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)using magnetic particle chemiluminescence immunoassays,and compared the results of serologic tests and nucleic acid test(NAT).Among 88 patients,95.45%were confirmed as positive by the combination of NAT and antibody test,which was significantly higher(P<0.001)than by single nucleic acid test(73.86%)or serologic test(65.91%).Then the correlation between temporal profile and the level of antibody response was analyzed.It showed that seroconversion started on day 5 after disease onset and IgG level was rose earlier than IgM.Comparison between patients with different disease severity suggested early seroconversion and high antibody titer were linked with less severe clinical symptoms.These results supported the combination of serologic testing and NAT in routine COVID-19 diagnosis and provided evidence on the temporal profile of antibody response in patients with different disease severity.
基金Supported by Guangdong Provincial Novel Coronavirus Scientific and Technological Project,No.2020111107001.
文摘BACKGROUND The coronavirus disease 2019(COVID-19)is an emerging infectious disease caused by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2).Suspected cases accounted for a large proportion in the early stage of the COVID-19 outbreak.The deviation of the nucleic acid test by throat swab(the current gold standard of COVID-19)caused by variation in sampling techniques and reagent kits and coupled with nonspecific clinical manifestations make confirmation of the suspected cases difficult.Proper management of the suspected cases of COVID-19 is crucial for disease control.CASE SUMMARY A 65-year-old male presented with fever,lymphopenia,and chest computed tomography(CT)images similar to COVID-19 after percutaneous coronary intervention.The patient was diagnosed as having bacterial pneumonia with cardiogenic pulmonary edema instead of COVID-19.This was based on four negative results for throat swab detection of SARS-CoV-2 nucleic acid using reverse transcriptase-polymerase chain reaction assay and one negative result for serological antibody of SARS-CoV-2 with the serological assay.Additionally,the distribution of ground-glass opacities and thickened blood vessels from the CT images differed from COVID-19 features,which further supported the exclusion of COVID-19.CONCLUSION Distinguishing COVID-19 patients from those with bacterial pneumonia with cardiogenic pulmonary edema can be difficult.Therefore,it requires serious identification.
基金Supported by grants from the Swedish Research Council, the Karolinska Institutet and the Swedish Society of Medicine (to CE) and National Institutes of Health grants DK-47987 (to PAD)
文摘The etiology of most cases of idiopathic bile acid malabsorption （IBAH） is unknown. In this study, a Swedish family with bile acid malabsorption in three consecutive generations was screened for mutations in the ileal apical sodium-bile acid cotransporter gene （ASBT; gene symbol, SLC10A2） and in the genes for several of the nuclear receptors known to be important for ASBT expression： the farnesoid X receptor （FXR） and peroxisome proliferator activated receptor alpha （PPARα）. The patients presented with a clinical history of idiopathic chronic watery diarrhea, which was responsive to cholestyramine treatment and consistent with IBAH. Bile acid absorption was determined using ^75Se-homocholic acid taurine （SeHCAT）; bile acid synthesis was estimated by measuring the plasma levels of 7α-hydroxy-4-cholesten-3-one （C4）. The ASBT, FXR, and PPARα genes in the affected and unaffected family members were analyzed using single stranded conformation polymorphism （SSCP）, denaturing HPLC, and direct sequencing. No ASBT mutations were identified and the ASBT gene did not segregate with the bile acid malabsorption phenotype. Similarly, no mutations or polymorphisms were identified in the FXR or PPARα genes associated with the bile acid malabsorption phenotype. These studies indicate that the intestinal bile acid malabsorption in these patients cannot be attributed to defects in ASBT. In the absence of apparent ileal disease, alternative explanations such as accelerated transit through the small intestine may be responsible for the IBAM.
基金supported by the Protein Research Center of Shahid Beheshti University.
文摘Diagnostic testing plays a fundamental role in the mitigation and containment of coronavirus disease 2019(COVID-19),as it enables immediate quarantine of those who are infected and contagious and is essential for the epidemiological characterization of the virus and estimating the number of infected cases worldwide.Confirmation of viral infections,such as COVID-19,can be achieved through two general approaches:nucleic acid amplification tests(NAATs)or molecular tests,and serological or antibody-based tests.The genetic material of the pathogen is detected in NAAT,and in serological tests,host antibodies produced in response to the pathogen are identified.Other methods of diagnosing COVID-19 include radiological imaging of the lungs and in vitro detection of viral antigens.This review covers different approaches available to diagnosing COVID-19 by outlining their advantages and shortcomings,as well as appropriate indications for more accurate testing.
基金support of Nova of Beijing science and Technology (No. 2010B108)National Natural Science Fond (No. 30701091)
文摘OBJECTIVE:To investigate anti-endotoxin action of four OAs reacted with endotoxin by the LAL assay with KTA.METHODS:Using a incubating kinetic tube reader and kinetic turbidimetric assay(KTA),the concentration-response time curve of endotoxin reacted with limulus amebocyte lysate(LAL) at 37℃ were obtained and the action of four organic acids(OAs) on it were investigated.The four OAs were benzoic acid,salicylic acid,syringic acid and 2-amino-benzoic acid from Radix isatidis.Meanwhile,the temperature variation caused by endotoxin with the four OAs was studied by the rabbit pyrogen test(RPT).RESULTS:It was showed that a low concentration(1 mg/mL) of the four OAs had a little effect of anti-endotoxin,and when the concentrations of the four OAs were 30 mg/mL,the endotoxin was neutralized completely.The relationships between the concentrations of endotoxin and the OAs were all linear with correlation coefficients of greater than 0.9995,indicating that the four OAs all had strong anti-endotoxin action,while syringic acid had the strongest action among the four OAs with IC50 of 12.84 mg/mL.CONCLUSION:The investigations of KTA agreed well with the results obtained by means of RPT.
文摘The study has shown free radical processes during modeling of Parkinson Disease (PD) with rotenone. We isolated striatum, brainstem, neocortex, cerebellum, spinal cord, thymus, heart, and liver of rats after rotenone injection in the right striatum. The samples were taken on the 5th, 10th and 15th days after the injection. According to chemiluminescence data, the injection of rotenone initiates the disturbance of intensity of free radical processes in striatum at 5th day in a bilateral mode. After this until the 10th day these changes had restoring character, but after 15 days according to chemiluminescence and thio-barbituric acid test disturbance of lipid peroxide oxidation processes occurred. While superoxide dismutase activity has been changed significantly in all studied tissues, especially in the striatum and neocortex. It should be noted that during rotenone model there are no observed clinical symptoms in rats during 1 to 20 days, and the symptoms of the disease are observed approximately 28 days after the injection. This research could help diagnose PD in the early stage of its onset.
文摘Objective: to explore the analysis and thinking of the results of two methods for unpaid blood donors in a certain area. Methods: 2000 blood samples from unpaid blood donors in a certain area were selected as the research object. The detection method was two times of different manufacturers ELISA reagents (Xinchuang/Wantai/Kehua). Six people were tested (ID-NAT) for those who were negative for both times. If positive, they were split again, subject to the (Roche or Kehua reagents) test (six people). Results: the positive rate of HIV 1/HCV/HBV NAT initial screening was 0.5%. Six samples were positive by ELISA at the same time, and five samples were positive by identification, with the positive rate of identification being 83.33%. The positive blood samples for twice, once positive and once negative were classified as three retest positive samples, and the negative samples for twice were classified as one retest negative sample. The negative initial screening positive S/CO value was 13.75 ± 2.40, and the negative S/CO value was 8.06 ± 6.05;The minimum value of positive S/CO in the initial screening of positive retest is 8.07, the minimum value of negative S/CO is 10.12, the minimum value of positive S/CO in the initial screening of negative retest is 9.13, and the minimum value of negative S/CO is 1.02. Conclusion: the results of ELISA and single ID-NAT test for unpaid blood donors are significant. The two methods can improve the accuracy of blood sample test for unpaid blood donors, and can effectively ensure the safety of clinical blood transfusion treatment.
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.
