Objective Recombinase-aided polymerase chain reaction(RAP)is a sensitive,single-tube,two-stage nucleic acid amplification method.This study aimed to develop an assay that can be used for the early diagnosis of three t...Objective Recombinase-aided polymerase chain reaction(RAP)is a sensitive,single-tube,two-stage nucleic acid amplification method.This study aimed to develop an assay that can be used for the early diagnosis of three types of bacteremia caused by Staphylococcus aureus(SA),Pseudomonas aeruginosa(PA),and Acinetobacter baumannii(AB)in the bloodstream based on recombinant human mannanbinding lectin protein(M1 protein)-conjugated magnetic bead(M1 bead)enrichment of pathogens combined with RAP.Methods Recombinant plasmids were used to evaluate the assay sensitivity.Common blood influenza bacteria were used for the specific detection.Simulated and clinical plasma samples were enriched with M1 beads and then subjected to multiple recombinase-aided PCR(M-RAP)and quantitative PCR(qPCR)assays.Kappa analysis was used to evaluate the consistency between the two assays.Results The M-RAP method had sensitivity rates of 1,10,and 1 copies/μL for the detection of SA,PA,and AB plasmids,respectively,without cross-reaction to other bacterial species.The M-RAP assay obtained results for<10 CFU/mL pathogens in the blood within 4 h,with higher sensitivity than qPCR.M-RAP and qPCR for SA,PA,and AB yielded Kappa values of 0.839,0.815,and 0.856,respectively(P<0.05).Conclusion An M-RAP assay for SA,PA,and AB in blood samples utilizing M1 bead enrichment has been developed and can be potentially used for the early detection of bacteremia.展开更多
Objective This study explored the potentially modifiable factors for depression and major depressive disorder(MDD)from the MR-Base database and further evaluated the associations between drug targets with MDD.Methods ...Objective This study explored the potentially modifiable factors for depression and major depressive disorder(MDD)from the MR-Base database and further evaluated the associations between drug targets with MDD.Methods We analyzed two-sample of Mendelian randomization(2SMR)using genetic variant depression(n=113,154)and MDD(n=208,811)from Genome-Wide Association Studies(GWAS).Separate calculations were performed with modifiable risk factors from MR-Base for 1,001 genomes.The MR analysis was performed by screening drug targets with MDD in the DrugBank database to explore the therapeutic targets for MDD.Inverse variance weighted(IVW),fixed-effect inverse variance weighted(FE-IVW),MR-Egger,weighted median,and weighted mode were used for complementary calculation.Results The potential causal relationship between modifiable risk factors and depression contained 459 results for depression and 424 for MDD.Also,the associations between drug targets and MDD showed that SLC6A4,GRIN2A,GRIN2C,SCN10A,and IL1B expression are associated with an increased risk of depression.In contrast,ADRB1,CHRNA3,HTR3A,GSTP1,and GABRG2 genes are candidate protective factors against depression.Conclusion This study identified the risk factors causally associated with depression and MDD,and estimated 10 drug targets with significant impact on MDD,providing essential information for formulating strategies to prevent and treat depression.展开更多
Objective Tick-borne encephalitis virus(TBEV) is an emerging pathogen in Europe and North Asia that causes tick-borne encephalitis(TBE). A simple, rapid method for detecting TBEV RNA is needed to control this disease....Objective Tick-borne encephalitis virus(TBEV) is an emerging pathogen in Europe and North Asia that causes tick-borne encephalitis(TBE). A simple, rapid method for detecting TBEV RNA is needed to control this disease. Methods A reverse-transcription recombinase-aided amplification(RT-RAA) assay was developed. This assay can be completed in one closed tube at 39℃ within 30 minutes. The sensitivity and specificity of RT-RAA were validated using non-infectious synthetic RNA representing a fragment of the NS5 region of the wild-type(WT) TBEV genome and the Senzhang strain. Additionally, 10 batches of tick samples were used to evaluate the performance of the RT-RAA assay. Results The analytical limit of detection of the assay was 20 copies per reaction of the TBEV synthetic transcript and 3 plaque-forming units(pfu) per reaction of TBEV titers. With the specific assay, no signal due to other arboviruses was observed. Of the 10 batches of tick samples obtained from the Changbai Mountains of China, three were TBEV-positive, which was consistent with the results of the quantitative real-time PCR assay. Conclusion A rapid, highly sensitive, specific, and easy-to-use method was developed for the detection of the TBEV Far-Eastern subtype.展开更多
Objective To prepare monoclonal antibodies against a newly discovered and conserved linear epitope of Rabies virus nucleoprotein and to use them in a rabies diagnostic test. Methods Synthetic peptide containing the ep...Objective To prepare monoclonal antibodies against a newly discovered and conserved linear epitope of Rabies virus nucleoprotein and to use them in a rabies diagnostic test. Methods Synthetic peptide containing the epitope was used as immunogen to prepare hybridoma cell lines by classical hybridoma technology. Anti-peptide monoclonal antibodies produced in ascites of inoculated Balb/c mice were labeled with fluorescein isothiocyanate （FITC） after purification and used in fluorescent antibody test （FAT）. Results Two positive hybridoma cell lines, RVNP-mAbl-CL and RVNP-mAb2-CL, were obtained. RVNP- mAbl-CL produced a higher concentration of monoclonal antibody RVNP-mAbl in Balb/c ascites. FITC-labeled RVNP-mAbl showed correct results on certain Rabies virus-positive canine brain tissue samples and cells of a small subclone of baby hamster kidney 21 cell line （BSR）. Conclusion FITC-labeled RVNP-mAbl has potential application for laboratory diagnosis of rabies展开更多
West Nile virus(WNV)causes West Nile fever and West Nile encephalitis.Because infection by WNV creates serious public health problems,its simple,rapid,and visual detection is very important in clinical practice,especi...West Nile virus(WNV)causes West Nile fever and West Nile encephalitis.Because infection by WNV creates serious public health problems,its simple,rapid,and visual detection is very important in clinical practice,especially in resource-limited laboratories.We have developed a rapid,specific,and highly sensitive internally controlled reverse transcription recombinase-aided amplification(RTRAA)assay to detect WNV,using both real-timefluoresce nee and the lateral flow dipstick(LFD)at39.0°C for 30 min.The analytical sensitivity of theRT-RAA assay was 10 plasmid copies and 1.6 pfu perreacti on with real-time fluoresce nee,and 1,000plasmid copies per reaction with the LFD.No crossreactionwith other control viruses was observed.Compared with the RT-qPCR assay,the RT-RAA assaydemonstrated 100%sensitivity and 100%specificityfor WNV.展开更多
Objective To perform pathological observation and etiological identification of specimens collected from dairy cows, beef cattle and dogs which were suspected of rabies in Inner Mongolia in 2012, and analyze their eti...Objective To perform pathological observation and etiological identification of specimens collected from dairy cows, beef cattle and dogs which were suspected of rabies in Inner Mongolia in 2012, and analyze their etiological characteristics. Methods Pathological observation was conducted on the brain specimens of three infected animals with Hematoxylin-Eosin staining, followed by confirmation using immunofluorescence and nested RT-PCR methods. Finally, phylogenetic analysis was conducted using the virus N gene sequence amplified from three specimens. Results Eosinophilic and cytoplasmic inclusion bodies were seen in neuronal cells of the CNS, and rabies non-characteristic histopathological changes were also detected in the CNS. The three brain specimens were detected positive. N gene nucleotide sequence of these three isolates showed distinct sequence identity, therefore they fell into different groups in the phylogenetic analysis. N gene in the cow and dog had higher homology with that in Hebei isolate, but that in the beef cattle had higher homology with that in Mongolian lupine isolate and Russian red fox isolate. Conclusion Rabies were observed in the dairy cow, beef cattle and canine in the farm in Inner Mongolia, in 2012, which led to a different etiologic characteristics of the epidemic situation.展开更多
Epstein-Barr virus(EBV)and cytomegalovirus(CMV),two of the most prevalent human herpesviruses,cause a wide spectrum of diseases and symptoms and are associated with serious health problem.In this study,we developed an...Epstein-Barr virus(EBV)and cytomegalovirus(CMV),two of the most prevalent human herpesviruses,cause a wide spectrum of diseases and symptoms and are associated with serious health problem.In this study,we developed an internal control reference recombinase-aided amplification(ICR-RAA)assay for the rapid detection of EBV and CMV within 30 min.The assay had a sensitivity of 5 and 1 copies/test for EBV and CMV,respectively,with no cross reaction with other pathogens.In comparison with those of the commercial quantitative polymerase chain reaction(qPCR),the sensitivity of the EBV and CMV ICR-RAAs using extracted DNA was 93.33%and 84.84%,respectively;the specificity was 98.75%and 100.00%,respectively;and the Kappa values were 0.930 and 0.892(P<0.05),respectively.In comparison with those of qPCR,the sensitivity of the EBV and CMV ICR-RAAs using the DNA by thermal lysis was 72.22%and 80.00%,respectively;the specificity was 100.00%。展开更多
Objective Knowledge of an enterovirus genome sequence is very important in epidemiological investigation to identify transmission patterns and ascertain the extent of an outbreak. The MinION sequencer is increasingly ...Objective Knowledge of an enterovirus genome sequence is very important in epidemiological investigation to identify transmission patterns and ascertain the extent of an outbreak. The MinION sequencer is increasingly used to sequence various viral pathogens in many clinical situations because of its long reads, portability, real-time accessibility of sequenced data, and very low initial costs. However, information is lacking on MinION sequencing of enterovirus genomes. Methods In this proof-of-concept study using Enterovirus 71 （EV71） and Coxsackievirus A16 （CA16） strains as examples, we established an amplicon-based whole genome sequencing method using MinION. We explored the accuracy, minimum sequencing time, discrimination and high-throughput sequencing ability of MinION, and compared its performance with Sanger sequencing. Results Within the first minute （min） of sequencing, the accuracy of MinION was 98.5% for the single EV71 strain and 94.12%-97.33% for 10 genetically-related CA16 strains. In as little as 14 min, 99% identity was reached for the single EV71 strain, and in 17 min （on average）, 99% identity was achieved for 10 CA16 strains in a single run. Conclusion MinION is suitable for whole genome sequencing of enteroviruses with sufficient accuracy and fine discrimination and has the potential as a fast, reliable and convenient method for routine use.展开更多
On December 21, 20：10, a stray dog consecutively attacked 10 people in Lengshui Village, Ningyuan County, Yongzhou City, Hunan Province, China. The dog was killed by the local CDC staff and vicinity villager, its bra...On December 21, 20：10, a stray dog consecutively attacked 10 people in Lengshui Village, Ningyuan County, Yongzhou City, Hunan Province, China. The dog was killed by the local CDC staff and vicinity villager, its brain tissue sample was taken within 24 h. The epidemic focus was disinfected and the injured people received post exposure prophylaxis （PEP）. Pathogens were detected in the tissue sample by the provincial CDC. The immunity and safety of rabies vaccine were assayed after PEP, the injured people were regularly followed up in the following 2 y and 6 mon.展开更多
Objective Unbiased next generation sequencing（NGS） is susceptible to interference from host or environmental sequences. Consequently, background depletion and virome enrichment techniques are usually needed for clin...Objective Unbiased next generation sequencing（NGS） is susceptible to interference from host or environmental sequences. Consequently, background depletion and virome enrichment techniques are usually needed for clinical samples where viral load is much lower than background sequences. Methods A viral Sequence Independent Targeted Amplification（VSITA） approach using a set of non-ribosomal and virus-enriched octamers（V8） was developed and compared with traditionally used random hexamers（N6）. Forty-five archived clinical samples of different types were used in parallel to compare the V8 and N6 enrichment performance of viral sequences and removal performance of ribosomal sequences in the step of reverse transcription followed by quantitative PCR（qP CR）. Ten sera samples from patients with fever of unknown origin and 10 feces samples from patients with diarrhea of unknown origin were used in comparison of V8 and N6 enrichment performance following NGS analysis. Results A minimum 30 hexamers matching to viral reference sequences（sense and antisense） were selected from a dataset of random 4,096（4~6） hexamers（N6）. Two random nucleotides were added to the 5＇ end of the selected hexamers, and 480（30 × 4~2） octamers（V8） were obtained. In general, VSITA approach showed higher enrichment of virus-targeted c DNA and enhanced ability to remove unwanted ribosomal sequences in the majorities of 45 predefined clinical samples. Moreover, VSITA combined with NGS enabled to detect not only more viruses but also achieve more viral reads hit and higher viral genome coverage in 20 clinical samples with diarrhea or fever of unknown origin. Conclusion The VSITA approach designed in this study is demonstrated to possess higher sensitivity and broader genome coverage than traditionally used random hexamers in the NGS-based identification of viral pathogens directly from clinical samples.展开更多
Objective To characterize two strains of street rabies virus （RABV） isolated from the brain tissue of cattle from Inner Mongolia. Differences in the histopathological and ultrastructural changes in the brain tissue ...Objective To characterize two strains of street rabies virus （RABV） isolated from the brain tissue of cattle from Inner Mongolia. Differences in the histopathological and ultrastructural changes in the brain tissue of infected mice were determired to reveal variation in the pathogenesis of infection between street rabies virus strains. Methods Ten-day-old mice were intracranially inoculated with one of three virus strains and brain tissue harvested when the mice were moribund. Various histopathological and ultrastructural markers of disease were then compared between the groups. Results Infection with the street virus strain CNMllO1C resulted in severe neuronal dendrites damage, but only mild cell apoptosis, T lymphocyte infiltration and microglial activation. Infection with the other street virus strain, CNMll03C, was characterized by cell apoptosis, T lymphocyte infiltration and microglial activation as well as dendrites damage. However, in comparison, infection with the attenuated virus strain CTN caused ~evere T lymphocyte infiltration, microglial activation and cell apoptosis, but left the neuronal dendrites intact. Conclusion The two street rabies virJs strains isolated from cattle from Inner Mongolia had different levels of virulence and caused distinct pathological changes in infected mice. Therefore, we concluded that different pathogenic mechanisms exist between different RABV strains.展开更多
To understand the epidemic situation and factors influencing rabies cases in children in China, we obtained an overview of the current epidemic based on individual data of rabies cases in children and a descriptive an...To understand the epidemic situation and factors influencing rabies cases in children in China, we obtained an overview of the current epidemic based on individual data of rabies cases in children and a descriptive analysis was carried on the prevalence and related factors. The results showed that the rabies cases in children accounted for 21.3% of the total number of rabies cases in China, 97.0% of these cases occurred in rural areas, they were mainly caused by dogs （81.5%）, and were primarily level Ill exposure （47.7%）. More than half of the cases were not treated with wound care, vaccination rate was extremely low （15.7%）, and only 5.9% of cases were injected with antibodies. Furthermore, 25.4% of cases adopted incorrect treatments such as extruding bleed and wound closure, cases vaccinated with 5 injections acco- unted for only 22.5%. In conclusion, the prevalence of rabies cases in children in China remains a serious concern, the number and immune status of dogs in rural areas, and knowledge of rabies by risk populations should be considered in future rabies prevention and control programs.展开更多
基金funded by the National Key R&D Program of China[2021YFC2301102]National Natural Science Foundation of China[82202593]Key R&D Program of Hebei Province[223777100D].
文摘Objective Recombinase-aided polymerase chain reaction(RAP)is a sensitive,single-tube,two-stage nucleic acid amplification method.This study aimed to develop an assay that can be used for the early diagnosis of three types of bacteremia caused by Staphylococcus aureus(SA),Pseudomonas aeruginosa(PA),and Acinetobacter baumannii(AB)in the bloodstream based on recombinant human mannanbinding lectin protein(M1 protein)-conjugated magnetic bead(M1 bead)enrichment of pathogens combined with RAP.Methods Recombinant plasmids were used to evaluate the assay sensitivity.Common blood influenza bacteria were used for the specific detection.Simulated and clinical plasma samples were enriched with M1 beads and then subjected to multiple recombinase-aided PCR(M-RAP)and quantitative PCR(qPCR)assays.Kappa analysis was used to evaluate the consistency between the two assays.Results The M-RAP method had sensitivity rates of 1,10,and 1 copies/μL for the detection of SA,PA,and AB plasmids,respectively,without cross-reaction to other bacterial species.The M-RAP assay obtained results for<10 CFU/mL pathogens in the blood within 4 h,with higher sensitivity than qPCR.M-RAP and qPCR for SA,PA,and AB yielded Kappa values of 0.839,0.815,and 0.856,respectively(P<0.05).Conclusion An M-RAP assay for SA,PA,and AB in blood samples utilizing M1 bead enrichment has been developed and can be potentially used for the early detection of bacteremia.
基金supported by Natural Science Foundation of Shandong ProvinceChina[ZR2022MH115]the National Natural Science Foundation of China[81301479,82202593]。
文摘Objective This study explored the potentially modifiable factors for depression and major depressive disorder(MDD)from the MR-Base database and further evaluated the associations between drug targets with MDD.Methods We analyzed two-sample of Mendelian randomization(2SMR)using genetic variant depression(n=113,154)and MDD(n=208,811)from Genome-Wide Association Studies(GWAS).Separate calculations were performed with modifiable risk factors from MR-Base for 1,001 genomes.The MR analysis was performed by screening drug targets with MDD in the DrugBank database to explore the therapeutic targets for MDD.Inverse variance weighted(IVW),fixed-effect inverse variance weighted(FE-IVW),MR-Egger,weighted median,and weighted mode were used for complementary calculation.Results The potential causal relationship between modifiable risk factors and depression contained 459 results for depression and 424 for MDD.Also,the associations between drug targets and MDD showed that SLC6A4,GRIN2A,GRIN2C,SCN10A,and IL1B expression are associated with an increased risk of depression.In contrast,ADRB1,CHRNA3,HTR3A,GSTP1,and GABRG2 genes are candidate protective factors against depression.Conclusion This study identified the risk factors causally associated with depression and MDD,and estimated 10 drug targets with significant impact on MDD,providing essential information for formulating strategies to prevent and treat depression.
基金supported by the National key research and development project [2017YFC1200505]the National Science and Technology Major Project of China [2018ZX10711001,2018ZX10101-002]the Development Grant of State Key Laboratory of Infectious Disease Prevention and Control [2015SKLID505,2014SKLID103]
文摘Objective Tick-borne encephalitis virus(TBEV) is an emerging pathogen in Europe and North Asia that causes tick-borne encephalitis(TBE). A simple, rapid method for detecting TBEV RNA is needed to control this disease. Methods A reverse-transcription recombinase-aided amplification(RT-RAA) assay was developed. This assay can be completed in one closed tube at 39℃ within 30 minutes. The sensitivity and specificity of RT-RAA were validated using non-infectious synthetic RNA representing a fragment of the NS5 region of the wild-type(WT) TBEV genome and the Senzhang strain. Additionally, 10 batches of tick samples were used to evaluate the performance of the RT-RAA assay. Results The analytical limit of detection of the assay was 20 copies per reaction of the TBEV synthetic transcript and 3 plaque-forming units(pfu) per reaction of TBEV titers. With the specific assay, no signal due to other arboviruses was observed. Of the 10 batches of tick samples obtained from the Changbai Mountains of China, three were TBEV-positive, which was consistent with the results of the quantitative real-time PCR assay. Conclusion A rapid, highly sensitive, specific, and easy-to-use method was developed for the detection of the TBEV Far-Eastern subtype.
基金supported by research grants from the Diagnosis of Infectious Pathogens and Combination of Diagnostic Technologies (2008ZX10004-002)Prevention and Control of Major Infectious Disease such as AIDS and Viral Hepatitis,State Eleventh Five-Year Plan
文摘Objective To prepare monoclonal antibodies against a newly discovered and conserved linear epitope of Rabies virus nucleoprotein and to use them in a rabies diagnostic test. Methods Synthetic peptide containing the epitope was used as immunogen to prepare hybridoma cell lines by classical hybridoma technology. Anti-peptide monoclonal antibodies produced in ascites of inoculated Balb/c mice were labeled with fluorescein isothiocyanate （FITC） after purification and used in fluorescent antibody test （FAT）. Results Two positive hybridoma cell lines, RVNP-mAbl-CL and RVNP-mAb2-CL, were obtained. RVNP- mAbl-CL produced a higher concentration of monoclonal antibody RVNP-mAbl in Balb/c ascites. FITC-labeled RVNP-mAbl showed correct results on certain Rabies virus-positive canine brain tissue samples and cells of a small subclone of baby hamster kidney 21 cell line （BSR）. Conclusion FITC-labeled RVNP-mAbl has potential application for laboratory diagnosis of rabies
基金supported by grants from the China Mega-Projects for Infectious Disease [2017ZX10302301-004-002,2018ZX10711001,2017ZX10104001,2018ZX10713-002]IVDC [2019HYDQNJJ03]
文摘West Nile virus(WNV)causes West Nile fever and West Nile encephalitis.Because infection by WNV creates serious public health problems,its simple,rapid,and visual detection is very important in clinical practice,especially in resource-limited laboratories.We have developed a rapid,specific,and highly sensitive internally controlled reverse transcription recombinase-aided amplification(RTRAA)assay to detect WNV,using both real-timefluoresce nee and the lateral flow dipstick(LFD)at39.0°C for 30 min.The analytical sensitivity of theRT-RAA assay was 10 plasmid copies and 1.6 pfu perreacti on with real-time fluoresce nee,and 1,000plasmid copies per reaction with the LFD.No crossreactionwith other control viruses was observed.Compared with the RT-qPCR assay,the RT-RAA assaydemonstrated 100%sensitivity and 100%specificityfor WNV.
基金supported by a grant from the National Department Public Benefit Research Foundation(201103032,200803014)
文摘Objective To perform pathological observation and etiological identification of specimens collected from dairy cows, beef cattle and dogs which were suspected of rabies in Inner Mongolia in 2012, and analyze their etiological characteristics. Methods Pathological observation was conducted on the brain specimens of three infected animals with Hematoxylin-Eosin staining, followed by confirmation using immunofluorescence and nested RT-PCR methods. Finally, phylogenetic analysis was conducted using the virus N gene sequence amplified from three specimens. Results Eosinophilic and cytoplasmic inclusion bodies were seen in neuronal cells of the CNS, and rabies non-characteristic histopathological changes were also detected in the CNS. The three brain specimens were detected positive. N gene nucleotide sequence of these three isolates showed distinct sequence identity, therefore they fell into different groups in the phylogenetic analysis. N gene in the cow and dog had higher homology with that in Hebei isolate, but that in the beef cattle had higher homology with that in Mongolian lupine isolate and Russian red fox isolate. Conclusion Rabies were observed in the dairy cow, beef cattle and canine in the farm in Inner Mongolia, in 2012, which led to a different etiologic characteristics of the epidemic situation.
基金the China Mega-Projects for Infectious Disease[grant no.2018ZX10711001,2017ZX10104001 and 2018ZX10713-002]the National Institute for Viral Disease Control and Prevention[grant no.2019HYDQNJJ03].
文摘Epstein-Barr virus(EBV)and cytomegalovirus(CMV),two of the most prevalent human herpesviruses,cause a wide spectrum of diseases and symptoms and are associated with serious health problem.In this study,we developed an internal control reference recombinase-aided amplification(ICR-RAA)assay for the rapid detection of EBV and CMV within 30 min.The assay had a sensitivity of 5 and 1 copies/test for EBV and CMV,respectively,with no cross reaction with other pathogens.In comparison with those of the commercial quantitative polymerase chain reaction(qPCR),the sensitivity of the EBV and CMV ICR-RAAs using extracted DNA was 93.33%and 84.84%,respectively;the specificity was 98.75%and 100.00%,respectively;and the Kappa values were 0.930 and 0.892(P<0.05),respectively.In comparison with those of qPCR,the sensitivity of the EBV and CMV ICR-RAAs using the DNA by thermal lysis was 72.22%and 80.00%,respectively;the specificity was 100.00%。
基金supported by the National key research and development plan(2016TFC1202700,2016YFC1200900)Beijing Municipal Science&Technology Commission project(grant numbers D151100002115003)Guangzhou Municipal Science&Technology Commission project(grant numbers 2015B2150820)
文摘Objective Knowledge of an enterovirus genome sequence is very important in epidemiological investigation to identify transmission patterns and ascertain the extent of an outbreak. The MinION sequencer is increasingly used to sequence various viral pathogens in many clinical situations because of its long reads, portability, real-time accessibility of sequenced data, and very low initial costs. However, information is lacking on MinION sequencing of enterovirus genomes. Methods In this proof-of-concept study using Enterovirus 71 （EV71） and Coxsackievirus A16 （CA16） strains as examples, we established an amplicon-based whole genome sequencing method using MinION. We explored the accuracy, minimum sequencing time, discrimination and high-throughput sequencing ability of MinION, and compared its performance with Sanger sequencing. Results Within the first minute （min） of sequencing, the accuracy of MinION was 98.5% for the single EV71 strain and 94.12%-97.33% for 10 genetically-related CA16 strains. In as little as 14 min, 99% identity was reached for the single EV71 strain, and in 17 min （on average）, 99% identity was achieved for 10 CA16 strains in a single run. Conclusion MinION is suitable for whole genome sequencing of enteroviruses with sufficient accuracy and fine discrimination and has the potential as a fast, reliable and convenient method for routine use.
基金supported by the National Department Public Benefit Research Foundation(201103032)
文摘On December 21, 20：10, a stray dog consecutively attacked 10 people in Lengshui Village, Ningyuan County, Yongzhou City, Hunan Province, China. The dog was killed by the local CDC staff and vicinity villager, its brain tissue sample was taken within 24 h. The epidemic focus was disinfected and the injured people received post exposure prophylaxis （PEP）. Pathogens were detected in the tissue sample by the provincial CDC. The immunity and safety of rabies vaccine were assayed after PEP, the injured people were regularly followed up in the following 2 y and 6 mon.
基金supported by grants from the National key research and development plan of China[2016TFC1202700,2016YFC1200903,and 2017YFC1200503]China Mega-Project for Infectious Disease[2017ZX10302301-004,2017ZX100101,and 2017ZX10104001]
文摘Objective Unbiased next generation sequencing（NGS） is susceptible to interference from host or environmental sequences. Consequently, background depletion and virome enrichment techniques are usually needed for clinical samples where viral load is much lower than background sequences. Methods A viral Sequence Independent Targeted Amplification（VSITA） approach using a set of non-ribosomal and virus-enriched octamers（V8） was developed and compared with traditionally used random hexamers（N6）. Forty-five archived clinical samples of different types were used in parallel to compare the V8 and N6 enrichment performance of viral sequences and removal performance of ribosomal sequences in the step of reverse transcription followed by quantitative PCR（qP CR）. Ten sera samples from patients with fever of unknown origin and 10 feces samples from patients with diarrhea of unknown origin were used in comparison of V8 and N6 enrichment performance following NGS analysis. Results A minimum 30 hexamers matching to viral reference sequences（sense and antisense） were selected from a dataset of random 4,096（4~6） hexamers（N6）. Two random nucleotides were added to the 5＇ end of the selected hexamers, and 480（30 × 4~2） octamers（V8） were obtained. In general, VSITA approach showed higher enrichment of virus-targeted c DNA and enhanced ability to remove unwanted ribosomal sequences in the majorities of 45 predefined clinical samples. Moreover, VSITA combined with NGS enabled to detect not only more viruses but also achieve more viral reads hit and higher viral genome coverage in 20 clinical samples with diarrhea or fever of unknown origin. Conclusion The VSITA approach designed in this study is demonstrated to possess higher sensitivity and broader genome coverage than traditionally used random hexamers in the NGS-based identification of viral pathogens directly from clinical samples.
基金supported by a grant from the National Department Public Benefit Research Foundation(201103032,200803014)
文摘Objective To characterize two strains of street rabies virus （RABV） isolated from the brain tissue of cattle from Inner Mongolia. Differences in the histopathological and ultrastructural changes in the brain tissue of infected mice were determired to reveal variation in the pathogenesis of infection between street rabies virus strains. Methods Ten-day-old mice were intracranially inoculated with one of three virus strains and brain tissue harvested when the mice were moribund. Various histopathological and ultrastructural markers of disease were then compared between the groups. Results Infection with the street virus strain CNMllO1C resulted in severe neuronal dendrites damage, but only mild cell apoptosis, T lymphocyte infiltration and microglial activation. Infection with the other street virus strain, CNMll03C, was characterized by cell apoptosis, T lymphocyte infiltration and microglial activation as well as dendrites damage. However, in comparison, infection with the attenuated virus strain CTN caused ~evere T lymphocyte infiltration, microglial activation and cell apoptosis, but left the neuronal dendrites intact. Conclusion The two street rabies virJs strains isolated from cattle from Inner Mongolia had different levels of virulence and caused distinct pathological changes in infected mice. Therefore, we concluded that different pathogenic mechanisms exist between different RABV strains.
基金supported by grants from the National Department Public Benefit Research Foundation(201103032)
文摘To understand the epidemic situation and factors influencing rabies cases in children in China, we obtained an overview of the current epidemic based on individual data of rabies cases in children and a descriptive analysis was carried on the prevalence and related factors. The results showed that the rabies cases in children accounted for 21.3% of the total number of rabies cases in China, 97.0% of these cases occurred in rural areas, they were mainly caused by dogs （81.5%）, and were primarily level Ill exposure （47.7%）. More than half of the cases were not treated with wound care, vaccination rate was extremely low （15.7%）, and only 5.9% of cases were injected with antibodies. Furthermore, 25.4% of cases adopted incorrect treatments such as extruding bleed and wound closure, cases vaccinated with 5 injections acco- unted for only 22.5%. In conclusion, the prevalence of rabies cases in children in China remains a serious concern, the number and immune status of dogs in rural areas, and knowledge of rabies by risk populations should be considered in future rabies prevention and control programs.
