Résumé
<p><b>OBJECTIVE</b>The aim of this study was to explore the prevalent characteristics of HBoV1 and its co-infection.</p><p><b>METHODS</b>PCR was used to detect HBoV1-DNA (HBoV1) and other viruses. A multivariate logistic regression model was used to explore possibility of co-detected for related viruses.</p><p><b>RESULTS</b>The positivity rates in Nanjing and Lanzhou were 9.38% (74/789) and 11.62% (161/1386), respectively (P>0.05). The HBoV1 positive group was younger than negative group (P<0.05). Seasonal differences were noted, with a higher frequency of infection in December and July. HBoV1-positive children [72.34% (169/235)] were co-infected with other respiratory viruses. Multifactorial analysis showed no correlations between HBoV1 and the clinical classification, region, gender, age, or treatment as an outpatient or in a hospital. Correlations were identified between HBoV1 infections with ADV (OR=1.53, 95% CI 1.03-2.28), RSV (OR=0.71, 95% CI 0.52-0.98), and IFVA (OR=1.77, 95% CI 1.00-3.13).</p><p><b>CONCLUSION</b>Presence of HBoV1 in nasopharyngeal aspirates did not correlate with region or gender, although the prevalence of HBoV1 was higher in younger children. There were no correlations between HBoV1 and other variables, except for the season and ADV, RSV, or IFVA infections.</p>
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Enfant d'âge préscolaire , Femelle , Humains , Mâle , Maladie aigüe , Chine , Épidémiologie , Comorbidité , ADN viral , Génétique , Bocavirus humain , Génétique , Modèles logistiques , Analyse multifactorielle , Infections à Parvoviridae , Épidémiologie , Virologie , Prévalence , Infections de l'appareil respiratoire , Épidémiologie , VirologieRésumé
<p><b>OBJECTIVE</b>To establish a rapid, sensitive and specific real-time PCR method for detection of Human Herpesvirus-6 (HHV-6).</p><p><b>METHODS</b>According to the reference, a pair of primers and a probe were designed located in U65-66 gene and to set up the standards. We established a real-time RT-PCR method for detection of HHV-6, and to verify the specificity, sensitivity, reproducibility.</p><p><b>RESULTS</b>The correlation coefficient was 0.999, E = 97.9%, the coefficient of variation values of Ct were 0.61% and 3.13% in real-time PCR assay for inter and intra assay, respectively. The results of all viruses were negative except of HHV-6 for the assay. The quantitative detection limit of the assay was 3 x 10(0) copies/microl.</p><p><b>CONCLUSION</b>The real-time PCR assay is highly specific, sensitive and reproducible, which can be used to quatitative detecting clinical samples.</p>
Sujets)
Humains , Herpèsvirus humain de type 6 , Génétique , Réaction de polymérisation en chaine en temps réel , Méthodes , Reproductibilité des résultats , RT-PCR , MéthodesRésumé
<p><b>OBJECTIVE</b>To discuss the enzyme linked immune spot test (ELISPOT) detected the cellular immune response induced by human Bocavirus (HBoV) VP2 virus-like particles (VLPs).</p><p><b>METHODS</b>After immunized by HBoV VP2 VLPs, the specific cellular immune response in mice were detected by ELISPOT assay, observe the ELISPOT results at the conditions of different polypeptide stimulate, different cell culture time, different cell concentration and different specific stimulus peptide concentration, then screening the right ELISPOT experimental conditions and establish the ELISPOT method.</p><p><b>RESULTS</b>The spots induced by HBoV1 VLPs immunized mice spleen lymphocytes stimulate with polypeptide P3 (GYIPIENEL) and P5 (LYQMPFFLL)were 233 spots/10(6) cells and 157 spots/10(6) cells,spots induced by HBoV2 VLPs immunized mice spleen lymphocytes stimulate with polypeptide P8 (GYIPVIHEL) were 113 spots/10(6) cells; 24 hours is the best time for culture, at this time HBoV1 and HBoV2 groups specificity secretion IFN-gamma ratio were 232 spots/10(6) cells and 119/10(6) cells; Best concentration of mice spleen lymphocyte is 5 x 10(5), right now HBoV1 and HBoV2 group specificity secretion IFN-gamma ratio were 232 spots/10(6) cells and 108/10(6) cells; Best concentration of polypeptides is 10 microg/ml, HBoV1 and HBoV2 group specificity secretion IFN -gamma ratio were 233 spots/10(6) cells and 96/10(6) cells.</p><p><b>CONCLUSIONS</b>HBoV1 and HBoV2 specificT-cell epitope in BABL/c mice were P3, P5 (HBoV1) and P8 (HBoV2). The best experiment condition were: cell cultivated for 24 h, cells concentration for 5 x 10(5) cells/well, stimulating polyperides concentration for 10 microg/ml, it can use to study the cellular immune induced by HBoV in mice.</p>
Sujets)
Animaux , Mâle , Souris , Séquence d'acides aminés , Test ELISpot , Méthodes , Déterminants antigéniques des lymphocytes T , Bocavirus humain , Allergie et immunologie , Immunité cellulaire , Interféron gamma , Souris de lignée BALB C , Données de séquences moléculaires , Virion , Allergie et immunologieRésumé
<p><b>OBJECTIVE</b>To investigate the prevalence of viral pathogen in children with severe pneumonia in Hunan.</p><p><b>METHOD</b>Bronchoalveolar lavage fluid [BALF] were collected from 122 hospitalized children with severe pneumonia in People's Hospital of Hunan province from January 2011 to December 2011. Nested- or reverse transcription Polymerase chain reaction (PCR or RT-PCR) was used to screen Adenovirus (ADV), Human Bocavirus (HBoV), Parainfluenzaviruses1-4 (PIV1-4), Human Respiratory Syneytial virus (RSV), Influenza virus A (IFVA), Influenza virus B (IFVB), Human Rhinovirus(HRV), Human Metapneumovirus (HMPV), human coronaviruses NL63 and HKU1 (HCoV-NL63, HCoV- HKU1).</p><p><b>RESULTS</b>Among the 122 bronchoalveolar lavage fluid, viral agents were detected in 60 samples(49.1%), among which ADV (40.98%) was the most common virus, followed by RSV (7.37%) and HBoV (7.37%). Two viruses were detected in 21 individual (35%) samples, of which 20 were dual positive for ADV (40%).</p><p><b>CONCLUSION</b>ADV is the most frequently detected viral etiology of severe pneumonia in children in Hunan during this year. And its Coinfection with other respiratory viruses was common.</p>
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Adolescent , Enfant , Enfant d'âge préscolaire , Femelle , Humains , Nourrisson , Mâle , Adénovirus humains , Liquide de lavage bronchoalvéolaire , Virologie , Pneumopathie infectieuse , Virologie , RT-PCR , Saisons , VirusRésumé
<p><b>OBJECTIVE</b>To investigate the status of enterovirus (EV) infection in children with acute lower respiratory tract infection (ALRTI).</p><p><b>METHODS</b>A total of 404 samples (with odd numbers) of nasopharyngeal aspirates were collected from the children who were hospitalized in the Children's Medical Center, Hunan Provincial People's Hospital due to ALRTI between September 2007 and April 2008. The conserved sequence in the 5'-noncoding region of EV was used to design the primer, and nested RT-PCR was performed to detect EV in the samples.</p><p><b>RESULTS</b>Of the 404 samples, 19 (4.7%) were EV-positive, and mostly taken from children under 3 years of age (95%); there was no significant difference in the detection rate between male and female children. Of the EV-positive children, 13 (68%) were clinically diagnosed with bronchial pneumonia, and 6 (32%) with bronchiolitis; 90% of them showed symptoms of fever, 84% had a cough, 63% had asthma, and 63% had complications mainly including diarrhea (6 cases), granulocytopenia (4 cases), and acute respiratory distress syndrome (2 cases). In addition, 26% of the EV-positive children had leukocyte disorder, more than half had liver dysfunction, and a few had myocardial involvement.</p><p><b>CONCLUSIONS</b>EV is a pathogen that should not be neglected in children with ALRTI. For these children, close attention should be paid to the epidemiological status and clinical features of EV infection, and blood routine examination, liver function test and myocardial enzyme assay should be carried out periodically to improve prognosis.</p>
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Enfant , Enfant d'âge préscolaire , Femelle , Humains , Nourrisson , Mâle , Maladie aigüe , Infections à entérovirus , Épidémiologie , Partie nasale du pharynx , Virologie , Infections de l'appareil respiratoire , VirologieRésumé
<p><b>OBJECTIVE</b>To understand the epidemiological characteristics of human metapneumovirus (hMPV) infection in children with acute lower respiratory tract infection (ALRTI) in Changsha area, China.</p><p><b>METHODS</b>A total of 2613 nasopharyngeal aspirate (NPA) specimens were collected from hospitalized children with ARTIs between September 2007 and February 2011 (a period of 3.5 years) in Changsha area, Hunan Province, China. Respiratory specimens were screened for hMPV M gene by reverse-transcription polymerase chain reaction (RT-PCR). All RT-PCR positive' amplification products were confirmed by sequencing or analyzed and compared with those in GenBank known hMPV reference strain.</p><p><b>RESULTS</b>hMPV was detected in 135 (5.2%) out of the 2613 children. The detected rate was significantly different between male and female (chi2 = 8.007, P = 0.003). The majority of the hMPV-positive patients (63.2%) were 0-1 year old infants. The majority of hMPV-positive patients were detected during spring season. Seasonal distribution showed that subtype A2b circulated predominantly in winter and spring, subtype B2 circulated predominantly in summer and spring. The most common genotype in 135 hMPV-positive patients were A and B in human subjects in Changsha. The predominant genotype of hMPV changed over the 3.5 year study period from genotype A2b to combined A2b and B2, and to B2. The 66 (48.9%) out of the 135 hMPV-positive patients were found to be co-infected with other respiratory viruses, and human bocavirus (HBoV) was the most common additional respiratory virus.</p><p><b>CONCLUSION</b>These data suggest that some cases of acute lower respiratory infection in young children in Changsha area are related to hMPV and the majority of children infected with hMPV were less than 1 years old, the detected rate of boys was higher than that of girls. It circulated predominantly in spring. The subtype A2b genetic lineage and the subtype B1 genetic lineage of hMPV were revealed alternately in human subjects in Changsha area and the hMPV exhibited high co-infection rate with other respiratory viruses.</p>
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Femelle , Humains , Nourrisson , Mâle , Maladie aigüe , Chine , Épidémiologie , Metapneumovirus , Classification , Génétique , Épidémiologie moléculaire , Infections à Paramyxoviridae , Épidémiologie , Infections de l'appareil respiratoire , Virologie , Facteurs tempsRésumé
<p><b>OBJECTIVE</b>To explore the viral etiology of acute low respiratory tract infection (ALRTI) among hospitalized children in Changsha of Hunan Province of China.</p><p><b>METHODS</b>Nasopharyngeal aspirates were collected from 1165 hospitalized children with ALRTI in Changsha from September 2007 to August 2008. Respiratory syncytin virus (RSV), human rhinovirus (HRV), influenza virus A (IFVA), influenza virus B (IFVB), parainfluenza 1-3 (PIV 1-3), human metapneumovirus (hMPV), human coronaviruses NL63 (HCoV-NL63), and human coronaviruses HKU1 (HCoV-HKU1) were detected by reverse transcription polymerase chain reaction (RT-PCR). Adenovirus (ADV) and human bocavirus (HBoV) were detected by standard polymerase chain reaction (PCR). WU polyomaviruses (WUPyV) and KI polyomaviruses(KIPyV) were detected by nested PCR. The positive samples further underwent genetic sequencing.</p><p><b>RESULTS</b>Among the 1165 nasopharyngeal aspirates, viruses were detected in 871 samples (74.76%), among which RSV (27.03%) was the most common virus, followed by HRV (17.33%), PIV3 (13.73%), HBoV (8.67%) and hMPV (6.52%). The overall positive rate of viral detection showed no significant differences between males and females (X2=2.241, P=0.134), whereas the positive rates of PIV3, hMPV, and HBoV in males were higher than in females. The positive rate of viral detection showed significant differences among different age groups (X2=10.934, P=0.027), and the highest positive rate was noted in the age group of 6 months to 1 year. Furthermore, the overall positive rate of viral detection showed a significant difference in term of seasonal distribution, with a peak prevalence in winter.</p><p><b>CONCLUSIONS</b>Virues predominate in the etiology of pediatric ALRTI in Changsha, and RSV, HRV and PIV3 are the main viruses for ALRTI. HBoV and hMPV have become increasingly important. Viral infection-associated ALRTI shows a prevail in the age group of 6 months to 1 year as well as in winter.</p>
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Adolescent , Enfant , Enfant d'âge préscolaire , Femelle , Humains , Nourrisson , Nouveau-né , Mâle , Répartition par âge , Enfant hospitalisé , Partie nasale du pharynx , Virologie , Infections de l'appareil respiratoire , Virologie , Saisons , Répartition par sexe , VirusRésumé
<p><b>UNLABELLED</b>To investigate the epidemiological features and types of human adenoviruses (ADV) in children with acute respiratory tract infection in Nanjing area, China. Nasopharyngeal aspirates and nasopharyngeal swabs were collected from 644 outpatients or hospitalized pediatric patients with ARTI at the Children Hospital of Nanjing, Jiangsu Province, China, between August 2010 and July 2011. Adenoviruses were identified and typed from the collected clinical specimens by nested-PCR based on the partial region of the hexon gene. Other 12 respiratory viruses including human bocavirus (HBoV), respiratory syncytial virus (RSV), human rhinovirus (HRV), parainfluenza viruses 1-4 (PIV1-4), influenza virus A/B (IFVA/B), human metapneumovirus (HMPV), human coronavirus NL63 and HKU1 (HCoV-HKU1 and HCoV-NL63) were also identified by PCR method. All PCR positive products were sequenced and phylogenetic analysis was conducted. It was showed that adenoviruses were detected in 171 patients out of 644 (26. 55%) children, 120 (70.18%, 120/171) for ADV3, 16 (9.36%,16/171) for ADV7, 12 (7.02%, 12/171) for ADV1, 10 (5.85%, 10/171) for ADV2, 6 (3.51%, 6/171) for ADV5, 3 (1.75%, 3/171) for ADV6, 3 (1.75%, 3/171) for ADV57, and 1 (0.58%,1/171) for ADV41. ADV infection could occur in any season. There was a higher possibility of ADV infection from April to July in 2011. Most cases (96.49%) were younger than 7 years old. A total of 99 of the 171 ADV-positive children (57.89%) were co-infected with other respiratory viruses. Respiratory syncytial virus (RSV) and human rhinovirus (HRV) were the most common additional respiratory viruses, Lower respiratory tract infections were the most frequent diagnoses made in the hospital, in which there were 52 pneumonia (30.4%) cases.</p><p><b>CONCLUSION</b>ADV is one of the most important pathogens of acute respiratory tract infection in children in Nanjing area, and adenovirus type 3 was the most prevalent serotype. It is important to develop long-term surveillance.</p>
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Enfant , Enfant d'âge préscolaire , Femelle , Humains , Nourrisson , Mâle , Adenoviridae , Classification , Génétique , Infections à Adenoviridae , Épidémiologie , Virologie , Chine , Épidémiologie , Données de séquences moléculaires , Phylogenèse , Infections de l'appareil respiratoire , Épidémiologie , VirologieRésumé
<p><b>OBJECTIVE</b>To study the virus spectrum of severe community-acquired pneumonia (CAP) and risk factors for the disease in children.</p><p><b>METHODS</b>Respiratory secretion specimens were collected from 1096 children hospitalized with CAP from June 2007 to November 2008, including 100 cases of severe CAP. Respiratory viruses were detected by PCR, nest-PCR or RT-PCR. Clinical data on the children were analyzed by univariate and multivariate logistic regression analysis for examining risk factors for severe CAP.</p><p><b>RESULTS</b>Viral pathogens were isolated from 82 (82%) of the 100 cases with severe CAP. RSV was the most common (37%), followed by HBoV (25%) and HRV (18%). Mixed infection was noted in 32 cases (32%). The presence of underlying diseases (OR=6.623, P<0.01) and RSV infection (OR=1.672, P<0.05) were risk factors for severe CAP in children, while age was a protective factor (OR=0.475, P<0.01).</p><p><b>CONCLUSIONS</b>RSV is the most frequent viral pathogen in children with severe CAP. The presence of underlying diseases and RSV infection may be risk factors for severe CAP, while age is a protective factor.</p>
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Enfant d'âge préscolaire , Femelle , Humains , Nourrisson , Nouveau-né , Mâle , Infections communautaires , Virologie , Bocavirus humain , Modèles logistiques , Pneumopathie virale , Virologie , Virus respiratoires syncytiaux , Facteurs de risqueRésumé
<p><b>OBJECTIVE</b>To investigate the prevalence and clinical characterization of HCoV-NL63 (NL63) in children with acute respiratory tract infections (ARTIs) in Lanzhou with other respiratory viruses. The prevalence of HBoV1 in ALRTI was obviously city,China.</p><p><b>METHOD</b>From November 2006 to October 2009,1169 nasopharyngeal aspirates (NPA) were collected from children under 14 years old with ARTIs. Samples were screened for NL63 using a reverse transcription-polymerase chain reaction (RT-PCR) and sequencing. Demography and clinical information were recorded.</p><p><b>RESULT</b>NL63 was detected in 35 (2.99%) of the 1169 children. The peak of the positive rate were in August, September 2007, July, August 2008 (23.53%,17.65%, 50%, 33.33% separately). There are no NL63 positive samples was detected in December, 2007 to February 2009. 25 (25/35, 71.43%) were co-infected with other respiratory viruses, and human rhinovirus (HRV) were the most common additional respiratory virus. No significant differences of infective rate of NL63 was found between < or = 3 years age group and > 3 years age group. Bronchiolitis and pneumonia were the most frequent diagnoses in NL63 positive patients and the major symptoms were fever and cough in our study. Between the monoinfection group and the coinfection group of NL63-positive patients, no differences were found in symptoms and clinical diagnoses except symptoms of gastrointestinal.</p><p><b>CONCLUSION</b>HCoV-NL63 is an important pathogen of acute respiratory tract infection in children in Lanzhou city. The peak of HCoV-NL63 infections was in summer. There were annual differences in the prevalence of HCoV-NL63. HCoV-NL63 infections existed a high rate of mixed infection, and mixed infection does not increase the severity of the disease.</p>
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Adolescent , Enfant , Enfant d'âge préscolaire , Femelle , Humains , Nourrisson , Nouveau-né , Mâle , Maladie aigüe , Épidémiologie , Chine , Épidémiologie , Coronavirus humain NL63 , Génétique , Prévalence , Infections de l'appareil respiratoire , Diagnostic , Épidémiologie , VirologieRésumé
<p><b>OBJECTIVE</b>The main objective of this study was to explore the prevalence and clinical characteristics of human coronavirus NL63 infection in hospitalized children with acute lower respiratory tract infection (ALRTI) in Changsha.</p><p><b>METHODS</b>Nasopharyngeal aspirates (NPA) samples were collected from 1185 hospitalized children with ALRTI at the People's Hospital of Hunan province, between September 2008 and October 2010. Reverse transcriptase polymerase chain reaction (RT-PCR) was employed to screen for coronavirus NL63, which is a 255 bp fragment of a part of N gene. All positive amplification products were confirmed by sequencing and compared with those in GenBank.</p><p><b>RESULTS</b>The overall frequency of coronavirus NL63 infection was 0.8%, 6 (60%) out of the coronavirus NL63 positive patients were detected in summer, 2 in autumn, 1 in spring and winter, respectively. The patients were from 2 months to two and a half years old. The clinical diagnosis was bronchopneumonia (60%), bronchiolitis (30%), and acute laryngotracheal bronchitis (10%). Four of the 10 cases had critical illness, 4 cases had underlying diseases, and 7 cases had mixed infection with other viruses. The homogeneity of coronavirus NL63 with those published in the GenBank at nucleotide levels was 97%-100%.</p><p><b>CONCLUSION</b>Coronavirus NL63 infection exists in hospitalized children with acute lower respiratory tract infection in Changsha. Coronavirus NL63 infections are common in children under 3 years of age. There is significant difference in the infection rate between the boys and the girls: the boys had higher rate than the girls. The peak of prevalence of the coronavirus NL63 was in summer. A single genetic lineage of coronavirus NL63 was revealed in human subjects in Changsha. Coronavirus NL63 may also be one of the lower respiratory pathogen in China.</p>
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Enfant d'âge préscolaire , Femelle , Humains , Nourrisson , Mâle , Maladie aigüe , Chine , Épidémiologie , Infections à coronavirus , Épidémiologie , Hospitalisation , Prévalence , Infections de l'appareil respiratoire , ÉpidémiologieRésumé
<p><b>OBJECTIVE</b>To obtain sufficient recombinant VP2 protein of human Bocavirus and establish it's seroepidemiology assying metbord. METHORD: Tbe capsid protein VP2 DNA genes of HBoV1 and 2 were optimized in accordance with tbe usage of the favorite codons in K coil so as to enhance its protein expression in prokaryotic expressing system. The protein was purified by Ni-NTA column, and its antigenicity was determined by Western Blot. Then establish ELISA to detect the specific anti-VP2 IgG antibodies against HBoV1 and 2 in healthy children aged 3-6 years in Nanjing, China.</p><p><b>RESULTS</b>The recombinant protein 6 x His-VP2 was produced in a larger quantity at 25 degrees C induced by IPTG (1 mmol/L) over night and purified by Ni-NTA column. Seropositive rates of HBoV1 and 2 were 62.2% and 55.5% and their mixed seropositivity was 37%.</p><p><b>CONCLUSION</b>The optimizing expression of the capsid protein VP2 from human Bocavirus constructed successfully and get a high yield under certain conditions. The established ELISA could be used to further analyze seroepidemiology of HBoV in China.</p>
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Enfant , Enfant d'âge préscolaire , Femelle , Humains , Mâle , Protéines de capside , Génétique , Test ELISA , Bocavirus humain , Réaction de polymérisation en chaîne , Études séroépidémiologiquesRésumé
<p><b>OBJECTIVE</b>To investigate the molecular epideiological and clinical feature of human metapneumovirus in children with acute respiratory tract infection in Nanjing city, China.</p><p><b>METHOD</b>Nasopharyngeal aspirates and nasopharyngeal swab were taken from 642 outpatients or hospitalized pediatric patients with acute at the Children Hospital of Nanjing, Jiangsu Province, China, between August 2009 and July 2010. Respiratory speciments were tested for the M gene of hMPV by reverse-transcription polymerase chain reaction (RT-PCR). All RT-PCR positive products were sequenced and phlogenetic analysis was conducted.</p><p><b>RESULT</b>hMPV was detected in 35 (5.5%) of the 642 children. Phylogenetic analysis revealed that 51.4% of the hMPV were B1, 31.4% were A2b. The peak of the positive rate was in April. The majority of the hMPV-positive patients(71.4%) were 0-1 years old. Of the 35 hMPV-positive patients, 15 (42.8%) were co-infected with other respiratory viruses, and human rhinovirus (HRV) were the most common additional respiratory virus. The most common clinical diagnosis was pneumonia (48.6%).</p><p><b>CONCLUSION</b>Human metapneumovirus is an important pathogen of acute respiratory tract infection in children in Nanjing city. The subtype B1 was the predominating lineage in 2009-2010 in Nanjing city. No significant differences were found for clinical characteristics between genotype A and genotype B human metapneumovirus infection in children in Nanjing.</p>
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Enfant d'âge préscolaire , Femelle , Humains , Nourrisson , Mâle , Maladie aigüe , Chine , Épidémiologie , Metapneumovirus , Classification , Génétique , Phylogenèse , Infections de l'appareil respiratoire , Épidémiologie , Virologie , RT-PCRRésumé
<p><b>OBJECTIVE</b>To investigate prevalence of Saffold virus (SAFV) in Changsha area of hospitalized children with respiratory tract infection, and to discuss whether this virus is related to respiratory tract infection of children.</p><p><b>METHODS</b>643 nasopharyngeal aspirates samples were collected from hospitalized children with respiratory tract infection of the first affiliated hospital of Hunan nomal university during Nov. 2007 to Oct. 2008. Real-time fluorescent quanti-tative PCR(FQ-PCR) performed to screen the 5'UTR gene. And then analyze clinical data.</p><p><b>RESULTS</b>SAFV were detected in 67 patients (10.42%) out of the 643 children, it was not detected over 5 years of age. The virus were detected in 8 patients (25.81%) out of the 31 children with persistent pneumonia and chronic pneumonia, there was statistically significant.</p><p><b>CONCLUSION</b>There existed SAFV infection in hospitalized children with lower respiratory infection in Changsha area; SAFV maybe related to disease onset with lower respiratory tract infection of children.</p>
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Adolescent , Enfant , Enfant d'âge préscolaire , Femelle , Humains , Nourrisson , Nouveau-né , Mâle , Cardiovirus , Génétique , Chine , Réaction de polymérisation en chaîne , Infections de l'appareil respiratoire , VirologieRésumé
<p><b>OBJECTIVE</b>To study the clinical and molecular epidemiology characteristics of human Bocavirus 1-3 (HBoV1-3) in children for acute respiratory infection in Lanzhou area.</p><p><b>METHODS</b>Nasopharyngeal aspiration samples and throat swabs were collected from 524 children with ARTI at the First Hospital of Lanzhou University, Gansu Province, China, between December 2009 and November 2010. Nested PCR was employed to screening HBoV1-3, which amplified a 518-bp fragment of the partial NS1 gene. Furthermore, a standard reverse transcription-PCR was used to screen for other common respiratory viruses.</p><p><b>RESULTS</b>The overall frequency of HBoV was 8.2% (43/524), lining up behind human rhinovirus, RSV, parainfluenza virus 3. Thirty of the HBoV-postive children(69.8%) were co-infected with other respiratory viruses. The prevalence of HBoV1 in ALRTI was obviously higher than that in AURI. The 2 HBoV2 NS1 sequences shared 99% and 100% nucleotide sequence identity with HBoV2 strain CU47TH respectively. Two cases of HBoV2 postive children appears gastrointestinal symptoms. The one HBoV3 NS1 sequences shared 99% nucleotide sequence identity with HBoV3 isolate 46-BJ07.</p><p><b>CONCLUSION</b>The HBoV3 was detected at the first time in lanzhou area. HBoV1-3 infection exists in children with acute respiratory tract infections in Lanzhou region, HBoV1 were dominant. The mixed infection rate was higher.</p>
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Femelle , Humains , Nourrisson , Mâle , Maladie aigüe , Chine , Bocavirus humain , Classification , Génétique , Phylogenèse , Infections de l'appareil respiratoire , VirologieRésumé
<p><b>OBJECTIVE</b>In order to understand the epidemiological and virologic characteristics of coronavirus HKU1 infection in hospitalized children with acute respiratory tract infection (ARTI) in Changsha.</p><p><b>METHODS</b>1165 nasopharyngeal aspirates (NPA) specimens were collected from hospitalized children with ARTI between September 2007 and August 2008 in Changsha. Specimens were screened for pol gene of coronavirus HKU1 by polymerase chain reaction. All positive amplification products were confirmed by sequencing and compared with those in GenBank.</p><p><b>RESULTS</b>Coronavirus HKU1 were detected in 12 patients (1.03%) out of the 1165 children. The patients were from 8 days to 3 years. The most common clinical diagnosis was bronchopneumonia(83.33%). Similarity of coronavirus HKU1 with those published in the GenBank at nucleotide levels was 98.18% - 100%.</p><p><b>CONCLUSION</b>Coronavirus HKU1 may be important pathogens in children with acute lower respiratory tract infection. Coronavirus HKU1 infections are common in children under 3 years old. There is no significant difference in the infectious rate between the boys and the girls. The peak of its prevalence is in spring and winter. A single genetic lineage of Coronavirus HKU1 was revealed in human subjects in Changsha.</p>
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Enfant d'âge préscolaire , Femelle , Humains , Nourrisson , Nouveau-né , Mâle , Maladie aigüe , Enfant hospitalisé , Chine , Coronavirus , Classification , Génétique , Phylogenèse , Réaction de polymérisation en chaîne , Infections de l'appareil respiratoire , VirologieRésumé
<p><b>OBJECTIVE</b>Human coronavirus (CoV)-HKU1 (HCoV-HKU1) was first isolated by Woo et al in Hong Kong. Several successive reports confirmed retrospectively that this new human coronavirus was circulating in different countries worldwide. However, the impact and the role of the emerging HCoV-HKU1 were not defined in children with ARTI. The objective of this study was to investigate the molecular epidemiology and clinical characteristics of HCoV-HKU1 infection in children with ARTI in Lanzhou, China.</p><p><b>METHOD</b>Nasopharyngeal aspiration (NPA) samples were collected from 301 children with ARTI at the First Hospital of Lanzhou University, Gansu Province, China, between November 2007 and October 2008. Demographic data and clinical findings of these children were collected at the same time. The informed consent was obtained from their parents. This study protocol was approved by the hospital ethics committee. The reverse transcription polymerase chain reaction (RT-PCR) was employed to screen HCoV-HKU1. Furthermore, other common respiratory viruses were screened in HCoV-HKU1 positive samples. All PCR positive products were sequenced, and phylogenetic analysis was conducted.</p><p><b>RESULT</b>The overall frequency of HCoV-HKU1 infection was 5.0% (15/301). The HCoV-HKU1 pol gene sequences shared a 95.8% - 99.6% nucleotide identity with the human coronavirus-HKU1 strain, whereas the amino acid identity was 90.7% - 99.3%. The phylogenetic analysis revealed that the HCoV-HKU1 strain pol gene clustered with the HCoV-HKU1 strain N15 genotype B (no. DQ415911); 11 of 15 HCoV-HKU1 positive sample tested were mixed-infection. HCoV-HKU1 was detected only from November to April. Positive specimens peaked in November. Children with HCoV-HKU1 infection varied in age from 15 day to 12-years (median age, 10 months). The clinical diagnoses of HCoV-HKU1 positive patients included those with AURI and LURI. The clinical presentations of HCoV-HKU1 positive children included fever, cough, sputum production, diarrhea, vomiting; pharynx engorgement, crackles, and wheezing. The mean hospital stay of the 14 patients was 9.9 days. Six of 15 HCoV-HKU1 positive patients had an underlying illness, and they were all inpatients (hospital stay, mean, 11.2 days). There was no statistically significant difference in the detection rate between the two groups with and without underlying illnesses.</p><p><b>CONCLUSION</b>Human CoV-HKU1 infection exists in children with respiratory tract infections in Lanzhou region. A single HCoV-HKU1 genotype B was circulating locally. The symptoms and clinical diagnoses of those infected with HCoV-HKU1 had no specificity as compared with patients with other common respiratory viruses infection.</p>
Sujets)
Enfant , Enfant d'âge préscolaire , Femelle , Humains , Nourrisson , Nouveau-né , Mâle , Chine , Épidémiologie , Coronavirus , Classification , Génétique , Épidémiologie moléculaire , Infections de l'appareil respiratoire , Épidémiologie , VirologieRésumé
<p><b>OBJECTIVE</b>To construct human metapneumovirus (hMPV) DNA vaccines and evaluate the cellular and humoral immune response in mice.</p><p><b>METHODS</b>Fusion protein FdeltaTM (without transmembrane domain) gene and M gene of hMPV were amplified from cDNA by PCR, then DNA vaccines pcDNA3.1His-FdeltaTM and pcDNA3.1His-M were constructed to verify the expression of F and M protein by Western blotting and indirect immunofluorescent assay (IFA) respectively. Serum IgG and spleen cell CTL were detected with ELISA and ELISPOT assay after the BALB/c mice were immunized intramuscularly with the vaccines.</p><p><b>RESULTS</b>The candidate DNA vaccines could express FdeltaTM and M protein as detected with Western blotting and IFA. The IgG antibody titers of mice was 1:44 when immunized with pcDNA3.1His-FdeltaTM, but could increase to 1:64 when co-immunized with pcDNA3.1His-M. ELISPOT assay demonstrated that IFN-gamma-secreting effector T cells reached 42 +/- 8.9 in co-immunization group, higher than single vaccine pcDNA3.1His-FdeltaTM group (32 +/- 7.4).</p><p><b>CONCLUSION</b>DNA vaccine pcDNA3.1His-FdeltaTM could induce specific cellular and humoral immune responses, and the immune response could increase when co-immunization with pcDNA3.1His-M was carried out.</p>
Sujets)
Animaux , Femelle , Humains , Souris , Anticorps antiviraux , Sang , Immunisation , Metapneumovirus , Génétique , Allergie et immunologie , Souris de lignée BALB C , Infections à Paramyxoviridae , Allergie et immunologie , Virologie , Vaccins à ADN , Génétique , Allergie et immunologie , Protéines virales , Génétique , Allergie et immunologie , Vaccins antiviraux , Génétique , Allergie et immunologieRésumé
<p><b>OBJECTIVE</b>To understand the genotypes of human metapneumovirus (hMPV) and the genetic character of hMPV attachment protein G sequence in Hunan, China.</p><p><b>METHODS</b>232 nasopharyngeal aspirates (NPA) samples from hospitalized children with acute respiratory infections were collected from Hunan, China in 2005. HMPV was detected. The full length of G glycoprotein genes were amplified and sequenced. Bioinformatics soft-wares were employed to analyze the sequences.</p><p><b>RESULTS</b>17/232 (7.3%) were showed hMPV positive. And co-infection rate with other viruses is 35%. The diagnoses of these hMPV positive cases are pneumonia, bronchiolitis and bronchopneumonia. Phylogenetic analysis for G genes from 13 hMPVs revealed the existence of four major subgroups: A1, A2, B1, B2 in Hunan, China in 2005. There are four types of sequence lengths of hMPV G glycoprotein, which are 711, 675, 660, 696nt. It is different in potential N-linked glycosylation sites and number of cysteine residues among these hMPVs of Hunan, China and Beijing, China. Also it is different from those in Japan and North America.</p><p><b>CONCLUSION</b>The investigation of hMPV from Hunan, China in 2005 revealed the high speed of genetic variation and the marked character of geographic epidemic differences.</p>
Sujets)
Enfant , Humains , Séquence d'acides aminés , Chine , Épidémiologie , Génotype , Glycoprotéines , Classification , Génétique , Metapneumovirus , Classification , Génétique , Données de séquences moléculaires , Phylogenèse , ARN viral , Génétique , Infections à virus respiratoire syncytial , Épidémiologie , Virologie , Similitude de séquences d'acides aminés , Protéines virales , Classification , GénétiqueRésumé
<p><b>OBJECTIVE</b>To investigate newly identified polyomavirus WUV and WUV and KIPyV are associated with acute respiratory infections in China, tests were developed to detect WUV and KIPyV gene fragments from nasopharyngeal aspirates collected from children with ARI fron Nov. 2006 to Oct. 2007.</p><p><b>METHODS</b>A total of 318 clinical samples were tested for WUV and KIPyV using PCR method. The positive products were sequenced and compared with those in GenBank.</p><p><b>RESULTS</b>14 of the 318 Samples were positive (WUV was 2.2%, KIPyV was 2.2%). All of children who were positive for WUV or KIPyV had respiratory illness.</p><p><b>CONCLUSION</b>Polyomavirus WU and KIPyV infection may be associated with upper and lower respiratory diseases.</p>