Objective To elucidate the prevalence and clinical characteristics of human metapneumovirus(hMPV)in hospital- ized children with respiratory infection.Methods A total of 452 hospitalized children with lower respiratory tract infection were observed from Aug 2004 to Jan 2005.Respiratory tract aspirates were collected from all patients within 48 hours after admis sion.The specimens were routinely tested for respiratory syncytial virus,influenza virus A and B,parainfluenza virus 1 to 3 and adenovirus by direct fluorescent assay(DFA).The 245 specimens negative by DFA were tested for hMPV by RT-PCR. PCR products of hMPV M gene from some patients were randomly selected for sequencing analysis.Results hMPV was identi- fied in 59(24.1%)of the 245 specimens tested,hMPV infection alone accounted for 13.1% of the infections in the 452 chil- dren under study,The prevalence of hMPV was higher than other respiratory viruses in winter.The mean age of hMPV-infec- ted children(n=59)was 27.7 months.There was no significant difference between age groups in terms of the prevalence of hMPV(P＞0.05).There were no statistically significant difference in demographics and clinical symptoms between hMPV in- fection and other common respiratory virus infection.Genotyping for the hMPV M gene from 23 Shanghai patients showed two distinct hMPV genotypes.Sequence analysis of these hMPV M genes showed 82.8%-100% homology to the registered se- quence in GenBank.There was no significant difference in clinical characteristics between the 2 genotypes.Conclusions hMPV plays an important pathogenic role in lower respiratory tract infection of children,hMPV prevailed in the winter of 2004.Clini- cally,hMPV infection can not be discriminated from the infection of other respiratory viruses.Clinical manifestation is similar between the two hMPV genotypes.

OBJECTIVE: To study the forensic application of Goldeneye DNA ID 26Y Kit in the She nationality. METHODS: Through capillary electrophoresis, the genotype of 26 Y-STR loci were analyzed in 53 unrelated male individuals from Fujian She nationality. The population genetics parameters such as allele frequency and haplotype diversity were calculated. The comparisons among the She nationality and the other nationalities were analyzed. RESULTS: A total of 126 alleles were observed on the 26 Y-STR loci of 53 unrelated male individuals. The allele frequencies and GD value ranged from 0.010 1 to 0.886 8 and 0.211 2 to 0.846 2, respectively. The GD value was greater than 0.5 in the 19 loci. A total of 47 haplotypes were observed. Based on R(ST), multidimensional scaling plot indicated that the genetic relationship among Fujian She nationality and Minnan Han nationality was closest, followed by Southern China Han nationality and Northern China nationality. CONCLUSION Goldeneye™ DNA ID 26Y Kit including 26 Y-STR loci has good polymorphism in the She nationality. As an additional system, it has forensic application value in some special cases.
Asian People/genetics* ; China ; Chromosomes, Human, Y/genetics* ; Ethnicity/genetics* ; Forensic Genetics ; Genetic Markers ; Genetics, Population ; Humans ; Polymerase Chain Reaction ; Polymorphism, Genetic ; Population Groups

OBJECTIVETo establish the triple-transgenic mouse model and study their biological characteristics by molecular biology, behavior and pathology.

METHODSHybrid the Tau and amyloid precursor protein (APP)/presenilins (PS1) transgenic mouse, the genotype of offspring mice were identified by PCR. Transcribed target genes were detected by RT-PCR. The protein expression of exogenous genes was detected by Western-blot. The pathological change of neurofibrillary tangles and senile plaque were observed by Bielschowsky silver staining and ABC immunohistochemical method. The changes time of learning and memory were observed by Morris water maze.

RESULTSAPP, PS1 and Tau genes were transcript in Tau/APP/PS1 mice. In 6 to 8 months old Tau/APP/PS1 mice, the neurofibrillary tangles and senile plaque could be found in cortex and hippocampus. In 6 months old Tau/APP/PS1 mice, the learning and memory abilities were worse.

CONCLUSIONWith the behavior change and pathological changes in Tau and beta-amyloid protein (AP), the Tau/APP/PS1 triple-transgenic mice can be used as a further study animal model of AD's pathogenesis and the target of drug treatment.

Alzheimer Disease ; pathology ; Amyloid beta-Protein Precursor ; genetics ; Animals ; Brain ; pathology ; Disease Models, Animal ; Learning ; Male ; Memory ; Mice ; Mice, Transgenic ; Neurofibrillary Tangles ; pathology ; Plaque, Amyloid ; pathology ; Presenilin-1 ; genetics ; tau Proteins ; genetics

OBJECTIVETo characterize the HA1 regions of hemagglutinin gene of influenza viruses (H3N2) isolated from children in Beijing from 1998 - 2004.

METHODSThe HA1 regions of hemagglutinin gene were amplified by RT-PCR from the viruses isolated and identified as A3 (H3N2) from clinical samples collected from infants and children during the peak seasons of influenza between 1998 and 2004. PCR products were sequenced or cloned into T-A vector and were analyzed after being sequenced.

RESULTSThe HA1 regions of hemagglutinin genes amplified from those isolates were 987 bp in length, encoding a protein of 329 amino acids in length. The identities of nucleotides and amino acids among these H3N2 isolates in Beijing and vaccines strains from 1998 - 2004 were 95.5% - 100.0% and 93.0% - 100.0%, respectively. The homology of the HA1 regions were related to the date of virus isolation, meaning the homology was higher among those strains isolated in nearer dates than others. Seven potential N-linked glycosylation sites in the HA1 regions located at amino acid positions 8, 22, 38, 63, 126, 165 and 285 were conserved in all the viruses analyzed. Two sites at 122 and 133 were inserted in those virus isolated after 1997, and another site at 144 appeared in those isolated after 1999. More amino acid substitutions located in the five putative antigenic sites or receptor binding sites were found more in the isolates than the isolates from previous year. Phylogenetic analysis showed new branches appeared continuously during 1998 - 2004. The strains isolated during winter in 2004 belonged to different branches, suggesting the appearance of new variants.

CONCLUSIONAmino acid substitutions continuously occurred in the HA1 regions of hemagglutinin genes in influenza virus (H3N2) isolated from children in Beijing from 1998 - 2004, which might have resulted in antigenic drift and led to the appearance of new variants.

Amino Acid Substitution ; China ; DNA, Viral ; analysis ; Gene Amplification ; Hemagglutinins ; genetics ; Humans ; Influenza A Virus, H3N2 Subtype ; genetics ; Influenza, Human ; virology ; Reverse Transcriptase Polymerase Chain Reaction ; Sequence Analysis, DNA

OBJECTIVETo establish a rapid, specific and effective technique for identifying subtyping A(1), A(3) and B of influenza virus isolates and clinical specimens as well as to analyze the sequences of nucleotides and deduced amino acids of HA1 regions from isolates of influenza virus A(3) isolated from 1996 to 2002.

METHODSSix inner and outer sets of oligonucleotide primers were designed to detect, type and subtype human influenza A and B. The first two corresponding sets differentiate type A and B of matrix (M) gene while, the second two corresponding sets identify the H(1) and H(3) subtypes of type A virus HA gene. To type and subtype influenza viruses in clinical isolates, a mixture of inner primer sets specific for H(1), H(3) and B were used in a single PCR reaction tube. To detect influenza viruses in clinical specimens, a mixture of the outer primer sets were used in a single primary PCR tube, and the inner ones in a single second PCR reaction tube. Amplified products were visualized in 1.2% agrose gel containing ethidium bromide. HA1 regions of hemagglutinin of 5 field strains (H3N2) isolated from 1996 to 2002 in Beijing were amplified by RT-PCR and sequenced directly.

RESULTSThere was 100% correlation between multiplex RT-PCR and culture to type and subtype influenza viruses from clinical isolates. For typing and subtyping, 76.9%, 57.1% and 86.5% were positive for A(1), A(3) and B by multiplex nested-PCR compared within virus isolation on culture, respectively. The sequence data of HA1 of A(3) strains showed that there was a high homology of nucleotide and amino acid, and the closer the date of isolating was, the higher homology showed.

CONCLUSIONSMultiplex RT-PCR and nested-PCR for influenza viruses could provide a useful alternative to existing methods of influenza detected and identified from clinical isolate and specimens. There were certain, continuous mutations and increasing glycosylated sites which might cause the antigen drift in the A(3) strains during 1996-2002 in Beijing area.

Amino Acid Sequence ; Child ; China ; epidemiology ; Hemagglutinin Glycoproteins, Influenza Virus ; genetics ; Humans ; Influenza A virus ; classification ; genetics ; isolation & purification ; Influenza B virus ; classification ; genetics ; isolation & purification ; Influenza, Human ; epidemiology ; virology ; Molecular Sequence Data ; Point Mutation ; Reverse Transcriptase Polymerase Chain Reaction ; methods ; Sensitivity and Specificity

OBJECTIVETo find out the importance of human bocavirus (HBoV) as an infectious agent for population in Beijing, China, seroprevalence study was conducted by using expressed recombinant major capsid VP2 protein as an antigen.

METHODSSerum specimens collected from infants and children who visited the Children's Hospital Affiliated to the Capital Institute of Pediatrics for health check up and adults visited the Xuanwu Hospital, Beijing for diseases other than respiratory infections from April 1996 to March 1997 were used for investigation. The major capsid protein VP2 from HBoV was expressed in E. coli strain BL21 (DE3) with the transformed PET30b vector inserted with full-length VP2 gene of HBoV and the specific antigenicity of this expressed protein was validated by previous study. Western blot was used to detect specific IgG antibody against HBoV in collected serum specimens diluted to 1:200. Mock expressed protein was E. coli cells strain BL21 (DE3) with the transformed PET30b vector without insert. Anti-His monoclonal antibody and rabbit anti-HBoV VP2 polypeptides hyper-immune serum were used as positive control for antibody detection.

RESULTSOut of 677 serum specimens tested, 400 (59.1%) were positive by Western blot. About 45.3% (34/75) of the newborns under 1 month of age had anti-HBoV antibodies, and antibody positive rates were lower in the age groups of 1 and 2 months (41.4% and 31.3%, respectively) and were higher in the following ages from 6 months to 7 years (from 45.6% to 69.7%). The antibody positive rates were at a relatively constant level (about 70%) in the age groups from 7 years to 40 years and became lower (61.8% - 62.8%) in groups of age over 50 years.

CONCLUSIONThe high seroprevalence against recombinant HBoV VP2 protein and early age antibody acquisition indicate that HBoV has been circulating in Beijing, China as early as in 1996 and most of children had been exposed to HBoV by the age of 7 years. Infants under the age of 6 months were susceptible to infection with this virus.

Adolescent ; Adult ; Antibodies, Viral ; blood ; Blotting, Western ; Bocavirus ; immunology ; Capsid Proteins ; immunology ; Child ; Child, Preschool ; China ; epidemiology ; Female ; Humans ; Immunoglobulin G ; blood ; Infant ; Infant, Newborn ; Male ; Middle Aged ; Parvoviridae Infections ; epidemiology ; immunology ; Prevalence ; Seroepidemiologic Studies ; Young Adult

OBJECTIVETo characterize the prevalence of influenza B virus infection in infants and young children in Beijing.

METHODSMDCK cell culture, indirect fluorescence assay (IFA) and hemagglutination inhibition (HI) assay were used to isolate and identify type B influenza viruses from clinical samples collected from outpatients and inpatients who visited the Affiliated Children's Hospital because of acute respiratory infections from Nov. 2000 to Jun. 2006.

RESULTSOut of 10,770 clinical samples collected during this surveillance period, 384 (3.57%, 384/10,770) were positive for influenza B viruses. Circulation of influenza B viruses was revealed in the later epidemic season of influenza viruses each year. The detection rate for influenza B virus was higher than 10% each year during the survey, except in the period from 2003--2004 which was 2.91%. The highest detecting rate was 23.69% of the specimens collected in Mar. 2006. During the period of this study, most of the influenza B virus were identified from children who visited the outpatient department of the Affiliated Children's Hospital. Among those outpatients who were positive for influenza B, 77.6% (264/340) were older than 3 years of age, whereas the inpatients positive for influenza B, 66.0% (29/44) were under 3 years of age. Coinfection of influenza B virus with other respiratory viruses was not common, only one of the influenza B virus positive specimen was found also positive for influenza A3. There was no significant difference in positive rate between influenza virus B and A3. A significantly higher positive rate of influenza B virus than that of influenza A3 virus was seen from Sep. 2005 to May 2006 (23.9% vs 1.1%). B/Yamagata/16/168 lineage viruses were dominant during 2000--2002, and B/Victoria/2/87 lineage viruses became dominant during 2002--2003. After 2003, co-circulation of Victoria and Yamagata lineages of influenza B viruses was identified with predominance of Yamagata lineage viruses, while Victoria lineage viruses predominated during the 2005--2006 epidemic season.

CONCLUSIONInfluenza B viruses were identified from February to May in every influenza season during this surveillance period of 2000--2006. Most of the positive specimens were those collected from outpatient department. Victoria and Yamagata lineages of influenza B viruses co-circulated in Beijing, China in recent years.

Adolescent ; Age Distribution ; Child ; Child, Preschool ; China ; epidemiology ; Female ; Humans ; Infant ; Influenza B virus ; classification ; isolation & purification ; Influenza, Human ; epidemiology ; virology ; Male ; Prevalence

BACKGROUNDHuman bocavirus (HBoV) is a newly identified human parvovirus that was originally detected in the respiratory secretions of children with respiratory infections. This study aimed to learn about the importance of HBoV infections by revealing the prevalence of serum antibodies against HBoV in Beijing population.

METHODSTwo batches of serum specimens collected in different periods were tested by Western blotting for specific IgG against HBoV using recombinant VP2 as antigen.

RESULTSOut of 677 serum specimens collected during April 1996 to March 1997, 400 (59.1%) were positive and antibody positive rate for another batch of 141 serum specimens collected in August, 2005 from adults aged from 20 years to over 60 years was 78.7% (111/141). Comparison of the sero-prevalence profiles for serum specimens collected during 1996 - 1997 to those collected in 2005 indicated that the antibody positive rate for specimens collected in 2005 was higher than that of the corresponding age groups collected during 1996 - 1997.

CONCLUSIONSThe data suggest that HBoV has been circulating in Beijing population for at least over 10 years, and most of children had been exposed to HBoV by age of 7 years. Higher HBoV antibody positive rate shown in the serum specimens collected in 2005 suggested that infections by HBoV have been increased in Beijing population in recent years.

Adult ; Antibodies, Viral ; blood ; Blotting, Western ; Bocavirus ; pathogenicity ; China ; epidemiology ; Humans ; Immunoglobulin G ; immunology ; Middle Aged ; Parvoviridae Infections ; blood ; epidemiology ; immunology ; Seroepidemiologic Studies ; Viral Proteins ; immunology ; Young Adult

OBJECTIVEHuman respiratory syncytial virus (hRSV) is the leading cause of acute upper and lower respiratory tract infections in infants and young children worldwide. Pediatric RSV disease claims more than 1 million lives annually. With the rapid development of specific anti-RSV agents and the spread of respiratory infections, RSV detection techniques with higher sensitivity, specificity and quicker performance are badly needed. This study was designed to develop a real-time polymerase chain reaction (PCR) for detection of RSV in nasopharyngeal aspirates.

METHODS(1) The TaqMan probe and primers of real-time PCR for RSV subgroup A and subgroup B detection were designed from the conserved region in N protein encoding gene, respectively. The sensitivity of real-time PCR was evaluated by using the virus with known amount of PFU. The specificity of real-time PCR for RSV detection was assessed by cross testing 10 isolates of strains A, 10 isolates of strains B, and by testing a variety of other respiratory viruses positive samples. (2) Sixty-one stored RSV positive respiratory samples and 103 nasopharyngeal aspirates were detected by real-time PCR, virus isolation, immunofluorescence assay (IFA), and nested-PCR.

RESULTS(1) The sensitivity of the real-time PCR developed in this study for RSV subgroup A detection was 5.25 pfu, and for subgroup B was 3.75 pfu, the same as that of nested-PCR. (2) No positive results were found in cross testing of other viruses positive specimens. (3) Twenty-seven out of 30 (90%) of RSV A stored samples and 27 out of 31 (87.1%) of RSV B stored samples were positive by the real-time PCR. (4) Thirty-five (34.0%) out of the 103 specimens were found RSV positive by real-time PCR (7 of them were subgroup A and 28 subgroup B); 31 (30.1%) specimens were positive by nested-PCR (6 of them were subgroup A and 25 subgroup B); 22 (21.4%) were found positive for RSV with IFA (5 of them were subgroup A and 17 subgroup B); RSV was isolated from 9 (8.7%) specimens (6 of them were subgroup A and 3 subgroup B). All the specimens found to be negative by real-time PCR were negative by rest of the methods used in this study.

CONCLUSIONThe real time PCR method developed in this project with the TaqMan probe and primers is sensitive and specific for detecting RSV subgroup A and B in nasopharyngeal aspirates.

Child ; DNA, Complementary ; isolation & purification ; Fluorescent Antibody Technique ; Humans ; Nasopharynx ; secretion ; virology ; Polymerase Chain Reaction ; methods ; RNA, Viral ; isolation & purification ; Respiratory Syncytial Virus Infections ; genetics ; Respiratory Syncytial Virus, Human ; genetics ; isolation & purification

OBJECTIVEA new human coronavirus, HCoV-NL63, was identified recently from two Dutch children with acute respiratory infection (ARI) by two scientists in the Netherlands in 2004. To investigate if this newly discovered virus is associated with acute respiratory infections in pediatric patients in Beijing, tests were developed to detect HCoV-NL63 gene fragments from throat swab and nasopharyngeal aspirates collected from children in outpatient and inpatient departments with ARI in Beijing from Dec. 2003 to Mar. 2004.

METHODSA total of 245 clinical samples, which were negative either for diagnostic tests of human respiratory syncytial virus, influenza virus A and B, adenovirus, parainfluenza virus 1, 2 and 3 by indirect immunofluorescence assay or human metapneumovirus by RT-PCR, were screened for HCoV-NL63 by nested PCR amplifying gene fragments located on the 1b and 1a genes. Amplicon of PCR from 1a gene of HCoV-NL63 was sequenced and the sequences were compared with those in GenBank nucleotide sequence database.

RESULTSThree (1.2%) out of the 245 samples were positive for HCoV-NL63 by nested-PCR using primers on 1b gene. These three samples also showed positive results on nested PCR in which primers were designed with sequences complementary to 1a gene segments. These positive samples were collected from hospitalized children under 2 years of age with pneumonia, bronchiolitis and bronchitis, respectively. The partial 1a gene sequences from two positive samples (BJ3140 and BJ3787) of HCoV-NL63 showed 100% homology between each other and high homology (98%-99%) with the sequences of 1a gene of HCoV-NL63 reported from different countries in GenBank. Phylogenetic analysis showed that BJ3140 and BJ3787 fell into the same genetic cluster (group 1).

CONCLUSIONSThese data suggest that some of acute respiratory infections in young children in Beijing area are related to the newly identified HCoV-NL63.

Acute Disease ; China ; Coronavirus ; genetics ; isolation & purification ; Databases, Nucleic Acid ; Humans ; Infant ; Phylogeny ; Polymerase Chain Reaction ; Respiratory Tract Infections ; virology ; Sequence Homology, Nucleic Acid