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 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

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 understand the impact of human parainfluenza virus (HPIV) on acute respiratory infections in infants and young children in Beijing.

METHODSMultiplex reverse transcription-PCR was used to amplify the hemagglutinin (HA) gene fragment of HPIV from clinical specimens. Primer pairs derived from a conserved region of the HA genes of HPIV were used to develop the multiplex RT-PCR for detecting and typing HPIV. The sensitivity and specificity of the method were determined by using various RNA and DNA viruses as controls. Specimens collected from 3519 children with acute respiratory infections from Aug. 2003 to Apr. 2006 were analyzed for HPIV by the multiplex RT-PCR as well as for other respiratory viruses by virus isolation and/or indirect immunofluorescent assay (IFA). Ten amplicons with expected molecular weight matching different types of HPIV were randomly selected for sequence analysis.

RESULTSOnly the cDNA from the isolated strains of HPIV 1 and 3 was positive by the multiplex RT-PCR. Phylogenetic analysis for those 10 amplicons' sequences which belong to HPIV 1 - 4 types respectively as determined by multiplex-PCR indicated that these specimens were truly HPIV positive. These 10 HPIV positive specimens included two specimens of type 4 which was further subtyped as HPIV4A and 4B by sequence analysis. With the multiplex RT-PCR, HPIV were detected in 349 out of 3519 specimens with the positive rate of 9.9% (349/3519), which is higher than 4.8% by the methods of virus isolation and/or IFA. And the HPIV positive rates were high in patients with not only acute upper but also lower respiratory tract infection. No regular seasonality distribution of HPIV infection was found. HPIV 1 and 3 were more common than HPIV 2 and 4.

CONCLUSIONWith higher sensitivity and specificity than virus isolation and IFA, multiplex RT-PCR is beneficial for the etiologic and epidemiologic studies on HPIV, as well as for HPIV typing. The data from this study indicate that HPIV is one of the important etiological viruses of acute respiratory tract infections in infants and young children in Beijing.

Child, Preschool ; China ; epidemiology ; Genes, Viral ; HN Protein ; genetics ; Humans ; Infant ; Paramyxoviridae Infections ; epidemiology ; virology ; Phylogeny ; Prevalence ; Respiratory Tract Infections ; epidemiology ; virology ; Respirovirus ; genetics ; isolation & purification ; Reverse Transcriptase Polymerase Chain Reaction ; Sensitivity and Specificity

OBJECTIVETo characterize the prevalence and occurrence of subgroups of human respiratory syncytial virus (RSV) in infants and young children with acute respiratory infections (ARI) in Beijing area.

METHODSRSVs were identified from nasopharyngeal aspirates and throat swabs collected from infants and children with ARI who visited the Children's Hospital Affiliated to Capital Institute of Pediatrics during the period of November 2000 to March 2006, by virus isolation in Hep-2 cells and antigen detection by indirect immunofluorescence assay (IFA). RT-PCR was used to differentiate subgroups A and B of RSV from part of the positive specimens.

RESULTSOut of 10 048 specimens including 7176 nasopharyngeal aspirates from inpatients and 2872 throat swabs from outpatients, 2286 (22.8%) were RSV positive. The positive rate for RSV identification were 30.0% (2153/7176) in specimens from the hospitalized patients, which was higher than that from outpatients (4.6%, 133/2872). The youngest of the RSV positive patients was 1 day after birth and the oldest was 15 years of age, with 73.0% younger than 1 year. Among those RSV positives, only 1.6% were older than 5 years. The ratio of male to female who were RSV positive was 2.4:1 (1598:674). The clinical diagnosis for 91.2% (1991) of those RSV positive patients was severe lower respiratory infections including bronchiolitis and pneumonia, whereas in only 8.8% (192) the diagnosis was upper respiratory infections. The data revealed that RSV started to be detected in October each year during the survey period and November to next April was the RSV season. The detection rate declined in May and almost no RSV could be found in summer. Positive rates for RSV detection were 42.3%, 41.0% and 40.5% in the seasons of 2001 - 2002, 2003 - 2004, 2005 - 2006, which were higher than those in seasons of 2000 - 2001 (14.0%), 2002 - 2003 (18.2%), 2004 - 2005 (20.4%). Subtyping of A and B during the surveillance period showed that 73.7% (691/938) were subgroup A and 26.3% (247/938) were subgroup B. Subgroup B was predominant in the 2000 - 2001 and 2004 - 2005 seasons, whereas subgroup A predominated in the 2001 - 2002, 2002 - 2003 and 2003 - 2004 seasons. Almost equal proportions of subgroup A and B appeared in 2005 - 2006 seasons.

CONCLUSIONThe data indicate that RSV is an important etiological agent for lower respiratory infections in infants and young children in winter and spring during the survey period. The pattern of RSV circulation varied alternately with higher rate every other year. The predominant subgroup changed between A and B, and co-circulated in equal proportion in some years.

Adolescent ; Cell Line, Tumor ; Child ; Child, Preschool ; China ; epidemiology ; Female ; Humans ; Infant ; Infant, Newborn ; Male ; Population Surveillance ; Prevalence ; Respiratory Syncytial Virus Infections ; diagnosis ; epidemiology ; Respiratory Syncytial Virus, Human ; genetics ; isolation & purification ; Respiratory Tract Infections ; diagnosis ; epidemiology ; virology ; Seasons

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