Relationship between viral load of human bocavirus and clinical characteristics in children with acute lower respiratory tract infection / 中国当代儿科杂志

<p><b>OBJECTIVE</b>To investigate the prevalence of human bocavirus (HBoV) in children with acute lower respiratory tract infection and to explore the relationship between the viral load of HBoV and the clinical characteristics of acute lower respiratory tract infection in children.</p><p><b>METHODS</b>A total of 1 554 nasopharyngeal aspirates from children who were hospitalized due to acute lower respiratory tract infection between March 2011 and March 2014 were collected. Quantitative real-time PCR was used to detect 12 RNA and 2 DNA viruses, adenovirus (ADV) and HBoV, and to measure the viral load of HBoV in HBoV-positive children. A comprehensive analysis was performed with reference to clinical symptoms and indicators.</p><p><b>RESULTS</b>In the 1 554 specimens, 1 212 (77.99%) were positive for viruses, and 275 (17.70%) were HBoV-positive. In HBoV-positive cases, 94.9% were aged <3 years, and there were more males than females. In the 275 HBoV-positive cases, 45 (16.36%) had single infection, and 230 (83.64%) had mixed infection. There was no significant difference in viral load between children with single infection and mixed infection (P>0.05). The patients with fever had a significantly higher viral load than those without fever (P<0.05). The children with wheezing had a significantly higher viral load than those without wheezing (P<0.05). There was no significant difference in viral load between children with mild, moderate, and severe acute lower respiratory tract infection (P>0.05).</p><p><b>CONCLUSIONS</b>HBoV is one of the important pathogens of acute lower respiratory tract infection in children. Children with a higher viral load of HBoV are more likely to experience symptoms such as fever and wheezing. However, the severity of disease and mixed infection are not significantly related to viral load.</p>

Virus detection in bronchoalveolar lavage fluid of 122 children with severe pneumonia / 中华实验和临床病毒学杂志

<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>

Enzyme-linked immunospot test detected specific cellular immune response induced by human bocavirus VP2 virus-like particles / 中华实验和临床病毒学杂志

<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>

Establishment and clinical application of TapMan real-time RT-PCR method for detection of HHV-6 / 中华实验和临床病毒学杂志

<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>

The epidemiological study of adenovirus in children with respiratory tract infections in Nanjing area from 2010 to 2011 / 病毒学报

<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>