Background: Multiplex virus assays are useful in immunocompromised hosts but still challenging in routine clinical settings in terms of their sensitivity, specificity, reproducibility, and time and cost performances. ...Background: Multiplex virus assays are useful in immunocompromised hosts but still challenging in routine clinical settings in terms of their sensitivity, specificity, reproducibility, and time and cost performances. In recent years, we developed a qualitative multiplex virus PCR assay capable of the simultaneous detection of 13 virus species within 3 h. However, because of the multiple and concomitant nature of this virus assay, it should be validated for qualitative reliability. Materials and Methods: As a preclinical examination, this multiplex PCR was able to detect 1.25 × 10<sup>3</sup> copies/mL of 13 synthesized virus genomes and preserved same virus DNAs by the serial dilution method. Blood samples from 40 patients who underwent hematopoietic stem cell transplantation were then examined by multiplex PCR for 13 virus species, followed by quantitative real-time PCR for all 13 virus species as reference PCR when these patients developed symptoms suggestive of viral infection. Results: In 421 cumulative qualitative-quantitative tests, the multiplex PCR certainly detected 1.0 × 103 copies/mL of 5 viruses (CMV, JCV, BKV, HHV-6, ADV) that were frequently detected and thus reasonably analyzed. The positive and negative predictive values of multiplex PCR were 84.2% - 93.3% and 90.7% - 99.0%, respectively, and sensitivity and specificity were 59.0% - 83.3% and 97.2% - 99.2%, respectively, for these 5 viruses. Conclusion: From these performances, the multiplex PCR assay may be acceptable in a routine clinical laboratory setting.展开更多
Community-acquired pneumonia(CAP) is one of the leading causes of morbidity and mortality in children worldwide.In this study,we aimed to describe the aetiology of viral infection of pediatric CAP in Chinese mainland....Community-acquired pneumonia(CAP) is one of the leading causes of morbidity and mortality in children worldwide.In this study,we aimed to describe the aetiology of viral infection of pediatric CAP in Chinese mainland.During November2014 to June 2016,the prospective study was conducted in 13 hospitals.The hospitalized children under 18 years old who met the criteria for CAP were enrolled.The throat swabs or nasopharyngeal aspirates(NPAs) were collected which were then screened 18 respiratory viruses using multiplex PCR assay.Viral pathogens were present in 56.6%(1539/2721) of the enrolled cases,with the detection rate of single virus in 39.8% of the cases and multiple viruses in 16.8% of the cases.The most frequently detected virus was respiratory syncytial virus(RSV)(15.2%,414/2721).The highest detection rate of virus was in <6-month-age group(70.7%,292/413).RSV,human metapneumovirus(HMPV),human parainfluenza viruses(HPIVs) and influenza B virus(Flu B) showed the similar prevalence patterns both in north and south China,but HPIVs,Flu A,human bocavirus(HBoV),human adenovirus(HAdV) and human coronaviruses(HCoVs) showed the distinct circulating patterns in north and south China.Human enterovirus/human rhinovirus(HEV/HRV)(27.6%,27/98),HBoV(18.4%,18/98),RSV(16.3%,16/98) and HMPV(14.3%,14/98) were the most commonly detected viruses in severe pneumonia cases with single virus infection.In conclusion,viral pathogens are frequently detected in pediatric CAP cases and may therefore play a vital role in the aetiology of CAP.RSV was the most important virus in hospitalized children with CAP in Chinese mainland.展开更多
Grass carp is one of the most important cultured fishes all over the world.The genetic diversity of grass carp plays an important role whatever in selective breeding progress or ecological conservation purposes.Howeve...Grass carp is one of the most important cultured fishes all over the world.The genetic diversity of grass carp plays an important role whatever in selective breeding progress or ecological conservation purposes.However,some genetic diversity researches were not accuracy and cannot be compared with each other due to different molecular markers,sample size and detection methods.In this study,we constructed five multiplex PCR assays contained 20 microsatellites with highly polymorphism and heterozygosity for evaluating genetic information of grass carp.We used nine cultured populations consisting of 507 individuals to detect stability of the five multiplex PCR assays.The results showed that the number of alleles(Na),effective number of alleles(Ne),observed heterozygosity(Ho),expected heterozygosity(He)and polymorphism information content(PIC)of the 20 microsatellite loci were relative high compared with the genetic diversity parameters of microsatellite loci developed by other researchers.Six loci were significantly deviated from Hardy-Weinberg equilibrium(P<0.01).And with exception of the Shaoguan,Indian and Nepal cultured population,all other cultured populations showed very high genetic diversity.Through the test of grass carp populations,we developed an effective and accurate multiplex SSR-PCR assays that can be as statistical powerful tool for detecting genetic information of grass carp.展开更多
Background: Meningitis remains a leading cause of death among children below 5 years of age in the Democratic Republic of the Congo (DR Congo). Distinguishing children with bacterial meningitis from those with viral m...Background: Meningitis remains a leading cause of death among children below 5 years of age in the Democratic Republic of the Congo (DR Congo). Distinguishing children with bacterial meningitis from those with viral meningitis in the emergency department is sometimes difficult. Here we identified bacteria and virus in the cerebral spinal fluid (CSF) of children with meningitis. Material and Methods: This is a prospective, analytical study carried out in the Pediatrics department of Panzi Hospital in the South-Kivu province of DR Congo. Between April 2021 and March 2022, 150 of 251 collected CSF from children aged from 1 to 59 months hospitalised due to clinical meningitis at Panzi referral university hospital, Bukavu, Eastern DR Congo were sent to the Lancet laboratory for bacteria identification by a multiplex real-time PCR assay for detection of the most different viruses and bacterial species causing meningitis. Result: The used multiplex real-time PCR assay allowed us to identify germs in 24.7% of cases (37/150). We isolated bacteria in 25/37 (67.5%) cases, and viruses in 9/37 (24.3%) while virus and bacteria co-infection was detected in 3/37 (8.1%). The most frequently identified bacteria were Streptococcus pneumoniae 14/37 (37.8%) followed by Haemophilus influenzae 6/37 (16.2%). The main virus was cytomegalovirus 5/37 (3.5%). Despite the age, the most found bacterial are common in children from rural areas and unvaccinated children. Bacterial and virus co-infection were identified in 66.7% of children aged between 25 - 60 months, mainly among male children, and in all children from rural areas (100%). The overall case fatality rate was 30% and was very high among cases with co-infection CMV-Pneumococcal (66.7%), followed by Streptococcus pneumoniae (50%). Conclusion: Meningitis remains frequent among children aged from one to 59 months among Bukavu Infants. We noticed that, Children with co-infection with bacteria and viruses might need higher attention when having meningitis symptoms, as this could lead to fatal outcomes. The introduction of molecular techniques, such as multiplex real-time PCR, has the potential to improve diagnosis and patient outcomes.展开更多
文摘Background: Multiplex virus assays are useful in immunocompromised hosts but still challenging in routine clinical settings in terms of their sensitivity, specificity, reproducibility, and time and cost performances. In recent years, we developed a qualitative multiplex virus PCR assay capable of the simultaneous detection of 13 virus species within 3 h. However, because of the multiple and concomitant nature of this virus assay, it should be validated for qualitative reliability. Materials and Methods: As a preclinical examination, this multiplex PCR was able to detect 1.25 × 10<sup>3</sup> copies/mL of 13 synthesized virus genomes and preserved same virus DNAs by the serial dilution method. Blood samples from 40 patients who underwent hematopoietic stem cell transplantation were then examined by multiplex PCR for 13 virus species, followed by quantitative real-time PCR for all 13 virus species as reference PCR when these patients developed symptoms suggestive of viral infection. Results: In 421 cumulative qualitative-quantitative tests, the multiplex PCR certainly detected 1.0 × 103 copies/mL of 5 viruses (CMV, JCV, BKV, HHV-6, ADV) that were frequently detected and thus reasonably analyzed. The positive and negative predictive values of multiplex PCR were 84.2% - 93.3% and 90.7% - 99.0%, respectively, and sensitivity and specificity were 59.0% - 83.3% and 97.2% - 99.2%, respectively, for these 5 viruses. Conclusion: From these performances, the multiplex PCR assay may be acceptable in a routine clinical laboratory setting.
基金This study was supported by National Science and Technology Supported Projects(grant number:2013BAI09B11)the National Major Science&Technology Project for Control and Prevention of Major Infectious Diseases in China(grant number:2018ZX10201002-008-008,2017ZX10103004-004)。
文摘Community-acquired pneumonia(CAP) is one of the leading causes of morbidity and mortality in children worldwide.In this study,we aimed to describe the aetiology of viral infection of pediatric CAP in Chinese mainland.During November2014 to June 2016,the prospective study was conducted in 13 hospitals.The hospitalized children under 18 years old who met the criteria for CAP were enrolled.The throat swabs or nasopharyngeal aspirates(NPAs) were collected which were then screened 18 respiratory viruses using multiplex PCR assay.Viral pathogens were present in 56.6%(1539/2721) of the enrolled cases,with the detection rate of single virus in 39.8% of the cases and multiple viruses in 16.8% of the cases.The most frequently detected virus was respiratory syncytial virus(RSV)(15.2%,414/2721).The highest detection rate of virus was in <6-month-age group(70.7%,292/413).RSV,human metapneumovirus(HMPV),human parainfluenza viruses(HPIVs) and influenza B virus(Flu B) showed the similar prevalence patterns both in north and south China,but HPIVs,Flu A,human bocavirus(HBoV),human adenovirus(HAdV) and human coronaviruses(HCoVs) showed the distinct circulating patterns in north and south China.Human enterovirus/human rhinovirus(HEV/HRV)(27.6%,27/98),HBoV(18.4%,18/98),RSV(16.3%,16/98) and HMPV(14.3%,14/98) were the most commonly detected viruses in severe pneumonia cases with single virus infection.In conclusion,viral pathogens are frequently detected in pediatric CAP cases and may therefore play a vital role in the aetiology of CAP.RSV was the most important virus in hospitalized children with CAP in Chinese mainland.
基金This work was supported by grants from the China's Agricultural Research System(CARS-46-04)the Project of Shanghai Engineering and Technology Center for Promoting Ability(16DZ2281200).
文摘Grass carp is one of the most important cultured fishes all over the world.The genetic diversity of grass carp plays an important role whatever in selective breeding progress or ecological conservation purposes.However,some genetic diversity researches were not accuracy and cannot be compared with each other due to different molecular markers,sample size and detection methods.In this study,we constructed five multiplex PCR assays contained 20 microsatellites with highly polymorphism and heterozygosity for evaluating genetic information of grass carp.We used nine cultured populations consisting of 507 individuals to detect stability of the five multiplex PCR assays.The results showed that the number of alleles(Na),effective number of alleles(Ne),observed heterozygosity(Ho),expected heterozygosity(He)and polymorphism information content(PIC)of the 20 microsatellite loci were relative high compared with the genetic diversity parameters of microsatellite loci developed by other researchers.Six loci were significantly deviated from Hardy-Weinberg equilibrium(P<0.01).And with exception of the Shaoguan,Indian and Nepal cultured population,all other cultured populations showed very high genetic diversity.Through the test of grass carp populations,we developed an effective and accurate multiplex SSR-PCR assays that can be as statistical powerful tool for detecting genetic information of grass carp.
文摘Background: Meningitis remains a leading cause of death among children below 5 years of age in the Democratic Republic of the Congo (DR Congo). Distinguishing children with bacterial meningitis from those with viral meningitis in the emergency department is sometimes difficult. Here we identified bacteria and virus in the cerebral spinal fluid (CSF) of children with meningitis. Material and Methods: This is a prospective, analytical study carried out in the Pediatrics department of Panzi Hospital in the South-Kivu province of DR Congo. Between April 2021 and March 2022, 150 of 251 collected CSF from children aged from 1 to 59 months hospitalised due to clinical meningitis at Panzi referral university hospital, Bukavu, Eastern DR Congo were sent to the Lancet laboratory for bacteria identification by a multiplex real-time PCR assay for detection of the most different viruses and bacterial species causing meningitis. Result: The used multiplex real-time PCR assay allowed us to identify germs in 24.7% of cases (37/150). We isolated bacteria in 25/37 (67.5%) cases, and viruses in 9/37 (24.3%) while virus and bacteria co-infection was detected in 3/37 (8.1%). The most frequently identified bacteria were Streptococcus pneumoniae 14/37 (37.8%) followed by Haemophilus influenzae 6/37 (16.2%). The main virus was cytomegalovirus 5/37 (3.5%). Despite the age, the most found bacterial are common in children from rural areas and unvaccinated children. Bacterial and virus co-infection were identified in 66.7% of children aged between 25 - 60 months, mainly among male children, and in all children from rural areas (100%). The overall case fatality rate was 30% and was very high among cases with co-infection CMV-Pneumococcal (66.7%), followed by Streptococcus pneumoniae (50%). Conclusion: Meningitis remains frequent among children aged from one to 59 months among Bukavu Infants. We noticed that, Children with co-infection with bacteria and viruses might need higher attention when having meningitis symptoms, as this could lead to fatal outcomes. The introduction of molecular techniques, such as multiplex real-time PCR, has the potential to improve diagnosis and patient outcomes.
