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

Objective To 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.Methods Serum 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 visiting the Xuanwu Hospital, Beijing for diseases other than respiratory infections from April 1996 to March 1997 were used for the 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 blotting 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.Results Out of 677 serum specimens tested, 400 (59.1% ) were positive for HBoV by Western blotting. About 45.3% (34/75) of the newborns under 1 month of age had anti-HBoV antibodies, and antibody positive rates were decreased in age groups of 1 and 2 months (41.4% and 31.3%, respectively) then increased in the following ages from 6 months to 7 years old ( from 45.6% to 69.7% ). The antibody positive rates were maintained at a relatively constant level ( about 70% ) in the age groups from 7 years to 40 years of age and became lower ( 61.8% - 62. 8% ) in those over 50 years.Conclusions The high seroprevalence of antibody against recombinant HBoV VP2 protein and early age antibody acquisition indicate that HBoV has been circulating in population of 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 this virus.

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 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

OBJECTIVESTo develop techniques which can be used to detect genetic material of measles virus from clinical samples to make diagnosis and differentiate atypical measles from other exanthematous infections early in clinical course.

METHODSA nested reverse transcriptase-polymerase chain reaction (RT-PCR) was developed to amplify gene fragment with the size of 301 bps from N gene of measles virus in throat swabs and urine samples collected from infants and children who were suspected measles cases. Before the test was used for clinical samples, preliminary tests were performed to determine the sensitivity and specificity of the test. The sensitivity of the test was determined by plaque assay using measles virus strain Edmonton and the specificity of the test was determined by cross-reaction with rubella virus, respiratory syncytial virus, influenza A and B viruses, enterovirus, adenovirus, human cytomegalovirus (hCMV), EB virus, and herpes simplex virus I. Serum specific IgM antibody against measles virus was also tested by ELISA.

RESULTSMeasles virus with the titer of 0.53 pfu could be detected by using the nested RT-PCR developed in this study. No amplification was found with the nested RT-PCR when rubella virus, respiratory syncytial virus, influenza A and B virus, enterovirus, adenovirus, hCMV, EB virus, and herpes simplex virus I were used as templates. Out of 116 throat swabs collected from suspected measles cases, 70 (60.3%) were measles RNA positive. For urine samples, 48 out of 74 (64.9%) were positive. Both throat swab and urine samples were collected simultaneously from 73 patients. Among those, 71 (97.3%) showed consistent results. Serum specimens were collected from 110 suspected patients. Among those, 65 (59.1%) and 61 (55.5%) were measles virus specific IgM antibody positive detected with ELISA kits from two different sources, respectively. Out of 110 sera samples, 106 (96.4%) showed consistent results. The consistency of the gene amplification and specific IgM antibody detection was 80.8% as shown by 84 out of 104 patients from whom throat swab and sera were collected at the same time.

CONCLUSIONThe data indicate that the nested RT-PCR developed in this study is sensitive and specific for detection of gene fragment of measles virus from clinical samples. The test is superior to the commonly used specific IgM antibody detection because of identifying gene material in early clinical stage, and even single clinical sample can be tested.

Humans ; Measles ; diagnosis ; genetics ; Measles virus ; genetics ; isolation & purification ; RNA, Viral ; genetics ; isolation & purification ; Reverse Transcriptase Polymerase Chain Reaction ; Sensitivity and Specificity

Human metapneumovirus (hMPV) is associated with acute respiratory tract infections (ARTI) in all age groups. However, there is limited information of genetic analysis of hMPV circulating in Beijing. To learn the characteristics of structural protein genes of human metapneumovirus circulating in children in Beijing, sequence analysis of matrix (M), small hydrophobic (SH) and attachment (G) proteins of hMPV from 2006 to 2010 was performed. Phylogenetic analysis of nucleotide sequences of 42 full length M genes, 49 SH gene and 55 G gene revealed that the hMPVs from pediatric patients were divided into sub-genotypes A2, B1 and B. There were highly conserved identities among M gene, with 7 conserved mutations of amino acids between A and B genotypes which were fairly conserved in the same genotype A or B. The amino acid identities of SH were 60.7% to 64.4% between different genotypes, 93.3% - 100% among same sub-genotype and 84.7% - 88.7% between different sub-genotypes. Use of alternative transcription-termination codon, nucleotide deletion and insertion resulted in variable length of nucleotide and deduced amino acid of G protein. Amino acid identities within same genotype ranged from 81.5% - 100%, whereas sequence identities between two genotypes ranged from 34.0% - 38.6% at the amino acid level. A new cluster of G genes in sub-genotype B2 appeared due to the same mutations and insertion of two amino acids in G protein encoding genes amplified from specimens collected from 2008 to 2010. Prediction of antigen sites of SH and G protein indicated that the variation of antigen sites between different sub-genotypes existed.
Child ; China ; epidemiology ; Genetic Variation ; Genotype ; Humans ; Metapneumovirus ; genetics ; Paramyxoviridae Infections ; blood ; epidemiology ; virology ; Phylogeny ; Retroviridae Proteins, Oncogenic ; blood ; genetics ; Viral Envelope Proteins ; blood ; genetics ; Viral Matrix Proteins ; blood ; genetics

OBJECTIVEThe present study was designed to explore the practical application of the rapid etiological diagnosis by detecting specific IgM antibody against common respiratory viruses in children with acute lower respiratory infections (ALRI).

METHODClinical specimens including nasopharyngeal aspirates and serum of acute phase from hospitalized children were collected from 207 infants and children with acute lower respiratory infections from March 2009 to September 2010. Seven common respiratory virus antigens were identified from the collected nasopharyngeal aspirates by direct immunofluorescence assay (DFA). ELISA was used to detect specific IgM antibody against RSV, ADV, IFVA, IFVB and PIV, while indirect immunofluorescence assay (IFA) was used to detect specific IgM antibody against RSV, ADV, IFVA, IFVB, PIV1, PIV2 and PIV3 in collected acute phase serum.

RESULTThe overall positive rates to detect viral antigen by using DFA, ELISA and IFA was 67.6%, 57.5% and 39.6%, respectively. The consistent rate of ELISA and IFA versus accepted DFA were 21.7% and 31.4%, respectively. The average days from onset of the symptoms to blood sample collection for those with the consistent results by ELISA and DFA were 12.0 d for ADV, 9.6 d for PIV2, 9.5 d for IFV, and 5.3 d for RSV, respectively, and by IFA and DFA were 15.0 d for PIV3, 9.2 d for ADV, and 7.4 d for RSV, respectively. Among all age groups, the consistent rate of serum viral IgM and antigen detections was highest in children younger than 3 years old.

CONCLUSIONAlthough there were differences between serum IgM antibody and viral antigen detections, specific IgM antibody detection was of value in early and rapid etiological diagnosis of pediatric ALRI, especially for young children. It could provide serologic evidence of respiratory virus infection. The diagnostic rate of pathogen could be improved if it was used in combination with viral antigen diagnostic methods.

Antibodies, Viral ; analysis ; blood ; Antibody Specificity ; Antigens, Viral ; analysis ; Child ; Child, Preschool ; Enzyme-Linked Immunosorbent Assay ; Female ; Fluorescent Antibody Technique ; Humans ; Immunoglobulin M ; analysis ; blood ; Infant ; Male ; Nasopharynx ; virology ; RNA Viruses ; genetics ; isolation & purification ; Respiratory Syncytial Virus Infections ; diagnosis ; virology ; Respiratory Syncytial Viruses ; genetics ; isolation & purification ; Respiratory Tract Infections ; diagnosis ; immunology ; virology ; Sensitivity and Specificity

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