BACKGROUND: Rapid detection of causative viruses is important for the management of acute respiratory illnesses. To increase the detection rate and decrease the turnaround time (TAT) and cost, we used 24-well plates instead of R-mix shell vials and changes the report time from once on day 3 to twice on days 1 and 5 of culture. The detection rate and TATs of each culture method, direct immunofluorescence assay (DFA), and multiplex reverse transcriptase polymerase chain reaction (mPCR) were compared. METHODS: Among 2,062 nasopharyngeal swabs (NPSs) received from January 2009 to January 2011, 707 NPSs were cultured in R-mix shell vials and 1,355 NPSs were cultured in 24-well plates. We analyzed 538 NPSs simultaneously using DFA, mPCR, and culture and compared the detection rate for 7 viruses (adenovirus, influenza A and B virus; parainfluenza virus 1, 2, and 3; and respiratory syncytial virus [RSV]). RESULTS: The detection rate when using shell vials was 28.4% (201/707) and was 29.4% (399/1,355) on day 1 and 33.3% (452/1,355) on day 5 when using 24-well plates. In addition, of the 53 viruses that were detected on day 5, 34 were adenovirus, 7 were parainfluenza virus, 4 were influenza A virus, 3 were influenza B virus, 4 were RSV, and 1 was a mix of influenza B and parainfluenza virus. The TAT when using shell vials and 24-well plates was 4.8 days and 2.5 days, respectively. The detection rate for the 7 respiratory viruses using culture, DFA, and mPCR was 24.3%, 20.8%, and 38.5%, and the TAT was 3.7 days, 1.0 day, and 1.4 days, respectively. CONCLUSIONS: Using 24-well plates for virus culture is an efficient method for the detection of respiratory viruses.
Adenoviridae ; Fluorescent Antibody Technique, Direct ; Influenza A virus ; Influenza B virus ; Influenza, Human ; Multiplex Polymerase Chain Reaction ; Paramyxoviridae Infections ; Respiratory Syncytial Viruses ; Reverse Transcriptase Polymerase Chain Reaction ; RNA-Directed DNA Polymerase ; Viruses

In this study, we constructed the plasmid of Sendai virus (SeV) BB1 strain minigenome with Gaussia luciferase (Gluc) as reporter and compared the rescue efficiency of SeV minigenome mediated by T7 promoter with that by CMV promoter. Firstly, the sequence was designed and synthesized which contained hammerhead ribozyme, sequence composed of the trailer, untranslated region of L gene, untranslated region of N gene, and the leader from SeV, and mutant hepatitis delta virus ribozyme sequence. Then, the synthesized sequence was inserted into pVAX1 containing CMV and T7 promoters and the general vector for SeV minigenome pVAX-miniSeV was obtained. Furthermore, pVAX-miniSeV-Gluc (+) and pVAX-miniSeV-Gluc(-) were obtained by inserting Gluc gene into pVAX-miniSeV. From the supernatant of BHK-21 cell transfected with pVAX-miniSeV-Gluc(+), high level of Gluc expression was detection indicating the normal transcription function of CMV promoter. pVAX-SeV-miniGluc(-) and plasmids expressing N,P and L protein of SeV were co-transfected into BST T7/5 cell which derived from BHK-21 and expressed T7 RNA polymerase stably. And high expression of Gluc was found, which indicated that SeV minigenome was efficiently rescued. However, we failed to repeat the result on BHK-21 cell, implying that T7 promoter and CMV promoter may have different effects on the rescue efficiency of SeV minigenome. Therefore, we further constructed SeV minigenome vectors pT7-miniSeV-Gluc (-) and pCMV-miniSeV-Gluc(-) with single promoter of T7 or CMV. Then, these vectors were transfected into BSR T7/ 5 cells respectively accompanied with the N, P, and L protein expression vectors. The result demonstrated that high expression of Gluc was found in the group of pT7-miniSeV-Gluc(-), which failed in the group of pCMV-miniSeV-Gluc(-). It indicated that T7 promoter significantly increased the rescue efficiency of SeV minigenome. We successfully constructed a SeV minigenome vector with secreted luciferase gene as report er and proved T7 promoter can enhance the rescue efficiency of SeV minigenome, which provides basis for construction of infectious clone containing SeV full-length genome.
Animals ; Cell Line ; Cricetinae ; Cytomegalovirus ; genetics ; DNA-Directed RNA Polymerases ; genetics ; Genome, Viral ; Humans ; Promoter Regions, Genetic ; Respirovirus Infections ; virology ; Sendai virus ; genetics ; physiology ; Viral Proteins ; genetics ; metabolism

OBJECTIVETo investigate the associations between Epstein-Barr virus (EBV) and human cytomegalovirus (HCMV) infections and the methylation levels of PTEN and hTERT genes and explore their roles in children with acute lymphoblastic leukemia (ALL).

METHODSBlood samples from 100 children with newly diagnosed acute lymphoblastic leukemia were centrifuged for serological detection of EBV and HCMV, and the patients were divided accordingly into EBV-infected group (n=20), HCMV-infected group (n=14), EBV and HCMV co-infected group (n=41), and non-infected group (control group, n=15). DNA was extracted from peripheral blood mononuclear cells (PBMCs) and modified with bisulfite ammonia sodium. The methylation levels of the promoters of PTEN and hTERT genes were detected with methylation-specific polymerase chain reaction (MS-PCR).

RESULTSCompared with those in non-infected group and EBV- or HCMV-infected group, the methylation levels of PTEN gene in the co-infected group were significantly decreased (P<0.05) while the methylation levels of hTERT gene significantly increased (P<0.05).

CONCLUSIONIn children with acute lymphoblastic leukemia, EBV and HCMV co-infection cause changes in the methylation levels of PTEN and hTERT. These results may be associated with epigenetic changes caused by viral infections, and further studies are needed to further verify this hypothesis.

Child ; Coinfection ; Cytomegalovirus ; isolation & purification ; Cytomegalovirus Infections ; DNA Methylation ; Epstein-Barr Virus Infections ; Herpesvirus 4, Human ; isolation & purification ; Humans ; PTEN Phosphohydrolase ; genetics ; metabolism ; Precursor Cell Lymphoblastic Leukemia-Lymphoma ; blood ; genetics ; virology ; Promoter Regions, Genetic ; Telomerase ; genetics ; metabolism

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 (
Adolescent ; Adult ; Child ; Child, Preschool ; Cytomegalovirus/genetics* ; Cytomegalovirus Infections/virology* ; DNA, Viral/analysis* ; Epstein-Barr Virus Infections/virology* ; Female ; Herpesvirus 4, Human/genetics* ; Humans ; Infant ; Infant, Newborn ; Male ; Middle Aged ; Nucleic Acid Amplification Techniques ; Recombinases/genetics* ; Young Adult

OBJECTIVETo investigate the pathogen of children with acute respiratory infection (ARI) in Suzhou and to provide some evidences for clinical diagnosis and treatment.

METHODSThe nasopharyngeal secretion samples from 2492 inpatient children with ARI, during the period of November 2005 to May 2007, were investigated for respiratory syncycial virus (RSV), influenza virus A and B, parainfluenza virus type 1, 2, 3 and adenovirus by both the indirect immunofluorescence assay and virus isolation. Human metapneumovirus (hMPV) were examined by reverse-transcription polymerase chain reaction (RT-PCR) at the same time.

RESULTSOf 2492 samples tested, 961 (38.6%) were positive. The total positive rate of virus pathogens in children with ARI was found related to age, season and respiratory disease. The detection rates by age were: 50.0% (412/824), 43.4% (190/438), 30.5% (207/679)and 27.6% (152/551), chi(2) = 96.5002, P < 0.01; the detection rates by season were : 46.7% (366/784), 13.8% (66/478), 13.8% (59/428) and 58.6% (470/802), chi(2) = 392.3279, P < 0.01; the detection rates by disease were (acute upper respiratory infection, acute laryngitis, throat-trachea-bronchitis, bronchial pneumonia, pneumonia genuine, bronchiolitis, bronchial asthma): 21.4% (30/140), 73.7% (14/19), 32.0% (8/25), 36.9% (598/1620), 13.1% (8/61), 66.1% (216/327) and 29.0% (87/300), chi(2) = 162.1276, P < 0.01. There was no association between the total positive rate and sex. The detection rates by sex were: 39.0% (588/1508) for male and 37.9% (373/984) for female, chi(2) = 0.2962, P > 0.05. The peak of RSV appeared from December to March. There was the highest RSV detection rate 50.2% (164/327) with bronchiolitis. The hMPV can be detected all year around. The peak of hMPV appeared in winter and the detection rate was 13.2% (106/802).

CONCLUSIONRSV and hMPV are the main respiratory viral pathogens in Suzhou. Detection of viral pathogens in children with respiratory infection could give fast, accurate diagnostic evidence, and help avoid antibiotics abuse.

Acute Disease ; Adenoviridae ; Adolescent ; Child ; Child, Hospitalized ; Child, Preschool ; China ; epidemiology ; Female ; Humans ; Infant ; Male ; Metapneumovirus ; isolation & purification ; Respiratory Syncytial Virus, Human ; isolation & purification ; Respiratory Tract Infections ; epidemiology ; etiology ; virology ; Sequence Analysis, DNA

OBJECTIVETo identify 6 major human herpesviruses with consensus primers and to explore its clinical application.

METHODSBased on the highly-homogeneous regions of DNA polymerase gene in human herpesviruses,Two pairs of primer were synthesized. One pair was designed to amplify herpes simplex virus type 1, type 2, Epstein-Barr virus and cytomegalovirus; and another was used to amplify varicella-zoster virus or human herpesvirus 6. Virus species identification was performed by restriction enzyme digestion with BamH I and BstU I. Thirty-eight CSF specimens of clinically diagnosed viral encephalitis,and 49 blood specimens from 27 confirmed cases and 22 clinically diagnosed ones were tested for herpes virus DNA using the PCR-RFLP assay with these primers.

RESULTSThirteen out of 38 CSF specimens (34.2%) were herpes virus positive. All blood specimens from 27 confirmed cases showed positive results, while for 22 clinically diagnosed cases 16 (72.7%) were positive. The types of herpes virus were determined using restriction enzyme digestion with BamH I and BstU I. Two CSF specimens from the patients, who were treated with aciclovir for 2 - 3 days, were still positive for herpes virus DNA by this method. None of the control blood or CSF controls were positive for herpesvirus by PCR.

CONCLUSIONThe PCR-RFLP method used in this study is a specific, sensitive and practicable one for diagnosis of herpes virus infection.

Child ; Cytomegalovirus ; isolation & purification ; Cytomegalovirus Infections ; virology ; DNA Primers ; DNA, Viral ; blood ; cerebrospinal fluid ; Epstein-Barr Virus Infections ; virology ; Female ; Herpesviridae ; isolation & purification ; Herpesviridae Infections ; virology ; Herpesvirus 4, Human ; isolation & purification ; Humans ; Male ; Polymerase Chain Reaction ; Polymorphism, Restriction Fragment Length ; Simplexvirus ; isolation & purification

BACKGROUND: Epstein-Barr virus (EBV) is causative agent of infectious mononucleosis and nasopharyngeal carcinoma and associated with Burkitt lymphoma and other tumors. The recombinant protein is needed for the rapid and sensitive serodiagnosis of EBV infection. METHODS: EBV gene encoding the protein reactive with the sera of EBV-infected patient was cloned and characterized with lambda gt11 expression library of cDNA of EBV B95-8 strain. RESULTS: The recombinant proteins from clone 12, 15 and 21 were expressed as 120, 118, 160 kDa-usion protein with beta-galactosidase, respectively, which were reactive with IgG anti-EBV antibody-positive sera, but not with anti-EBV antibody-negative sera. A homology search of the DNA sequence of the cloned gene with EBV B95-8 sequences revealed that those were located at 61716~62087, 61898~62085, and 102128~103158, respectively. These positions correspond to BFRF3, BFRF3, and BZLF1, respectively, which were reported as immunogenic protein which evoked strong and longstanding antibody response and had no sequence homology with the proteins of other herpesviruses. All the patients' sera were reactive with clone 12 protein, but only 5 out of 9 patients' sera were reactive with clone 21 protein. CONCLUSION: Clone 21 protein expressing BFRF3 fragment was immunoreactive in patient sera from natural EBV infection and was regarded as useful candidate for the serodiagnosis of EBV infection.
Antibody Formation ; Base Sequence ; beta-Galactosidase ; Burkitt Lymphoma ; Clone Cells* ; Cloning, Organism* ; DNA, Complementary ; Epstein-Barr Virus Infections ; Herpesviridae ; Herpesvirus 4, Human* ; Humans ; Immunoglobulin G ; Infectious Mononucleosis ; Recombinant Proteins ; Sequence Homology ; Serologic Tests

To establish a fluorescent quantitative PCR method (FQ-PCR) with TaqMan probe for simultaneous detection of polyomavirus (BKV) and cytomegalovirus (CMV) and to evaluate its clinical application in the renal transplantation recipients. The conservative sequences of BKV and CMV were targeted and amplified by nested PCR technique. The PCR products were cloned into the plasmids pcDNA3. 1(+). The recombinant plasmid containing target sequences of BKV and CMV were constructed as external standards. The TaqMan-based assay was optimized. For evaluating the assay, the sensitivity was determinated by diluted standard (5 X 103-10icopies/mL), and the specificity was verified by negative control and positive control, and the precision was assessed by intra-assay coefficient of variation (ICV) through detecting standard repeatedly (20 times). A total of 480 blood samples of renal transplantation recipients were used to detect BKV and CMV DNA simultaneously with FQ-PCR, and the concentrations of FK506 were measured by ELISA. The association of DNA copy and concentrations of FK506 was analyzed. The cloned target BKV and CMV DNA was confirmed by sequencing and analysis. The sensitivity of the FQ-PCR assay reached 5 X 103 copies/ml in detecting BKV or CMV DNA. Control DNA verified the assay specifically detecting target DNA. The precision of the assay to quantif target DNA copies was acceptable (Intra-assay CV was 3.44% for BKV and 2.23% for CMV; Inter-assay CV was 4. 98% for BKV and 3.76% for CMV;). Of 480 samples, 130 samples (27. 08%) were CMV DNA positive, significantly higher than the BKV DNA positive (13.33%, 64/480, P<0.05). The positive BKV or CMV DNA was found to be associated with high concentrations of FK506 (P<0. 05). In conclusion, the developed real-time PCR assay for detecting both CMV and BKV DNA simultaneously was s high sensitive, precise and time-effectiveand could be applied in the monitoring of the CMV and BKV infection in the renal transplantation recipients.
Adolescent ; Adult ; Aged ; Conserved Sequence ; Cytomegalovirus ; genetics ; isolation & purification ; Cytomegalovirus Infections ; diagnosis ; virology ; DNA, Viral ; blood ; Female ; Humans ; Immunosuppressive Agents ; blood ; Kidney Transplantation ; adverse effects ; Male ; Middle Aged ; Polyomavirus ; genetics ; isolation & purification ; Polyomavirus Infections ; diagnosis ; virology ; Real-Time Polymerase Chain Reaction ; methods ; Reproducibility of Results ; Sensitivity and Specificity ; Species Specificity ; Tacrolimus ; blood ; Time Factors ; Tumor Virus Infections ; diagnosis ; virology ; Viral Load ; Young Adult

OBJECTIVETo determine whether the transfusion-transmitted virus (TTV) is hepatotropic.

METHODSTotal DNA was extracted from various tissues of 5 experimentally infected Rhesus monkeys during the viremic period. A dot hybridization was done with viral double stranded DNA probes or single antisense probes.

RESULTSThe double-stranded probe was hybridized with DNA from the liver, bone marrow, spleen,stomach, small intestine and colon. The single-stranded antisense probe was hybridized with DNA from the liver, small intestine and bone marrow of all 5 monkeys, but not with that from other tissues.

CONCLUSIONSAs the viral genome was of negative polarity, the plus-stranded fragment identified in our study might be a replicative intermediate, and was only demonstrated in the liver, small intestine, and bone marrow by dot blot hybridization with single-stranded antisense probes. It is suggested that the TTV replicates in the liver, bone marrow and small intestine, and TTV might be hepatotropic.

Animals ; Bone Marrow ; virology ; DNA Virus Infections ; virology ; DNA, Viral ; analysis ; Intestine, Small ; virology ; Liver ; virology ; Macaca mulatta ; Torque teno virus ; genetics ; isolation & purification ; physiology ; Virus Replication

OBJECTIVETo determine the plasma level of Epstein Barr virus (EBV) DNA in children with EBV associated diseases, and to investigate the dynamic changes of EBV DNA level after initial infection as well as the relationship between EBV DNA level and the diseases severity.

METHODSThe subjects consisted of 73 children with primary EBV infection (infectious mononucleosis, pneumonia,etc.) and 18 children with severe EBV-associated diseases (chronic active EBV infection, hemophagocytic lymphohistiocytosis, etc.). The plasma EBV DNA level was detected by a real-time PCR assay.

RESULTSThe plasma EBV DNA level decreased with the infection time in children with primary EBV infection. Two weeks after infection, plasma EBV DNA was almost undetectable. The positive rate of plasma EBV DNA in children with severe EBV associated diseases increased significantly when compared with that in children with primary EBV infection (89% vs 16%; p<0.05).

CONCLUSIONSThe level of EBV replication may be reduced with the infection time. Dynamic determination of blood EBV DNA is useful for the evaluation of disease severity in children with EBV infection.

DNA, Viral ; blood ; Epstein-Barr Virus Infections ; virology ; Humans ; Infectious Mononucleosis ; virology ; Lymphohistiocytosis, Hemophagocytic ; virology ; Virus Replication