[Analysis of pathogenic features and infection status of human parainfluenza virus type 3 among children in Hangzhou].

Objective: To determine the level of genetic variation of human parainfluenza virus type 3 (HPIV-3), and to describe infection and co-infection characteristics of HPIV-3 in children.

Methods: Single respiratory samples from 856 pediatric patients with acute respiratory tract infection (ARI) in Hangzhou were collected from December 2009 to March 2013. All samples were screened for HPIV-3 by real-time RT-PCR and followed by HN sequencing and phylogenetic analysis.

Interim estimates of divergence date and vaccine strain match of human influenza A(H3N2) virus from systematic influenza surveillance (2010-2015) in Hangzhou, southeast of China.

Objectives: In the post-pandemic period 2010-2015, seasonal influenza A(H3N2) virus predominated in Hangzhou, southeast of China, with an increased activity and semi-annual seasons. This study utilized HA virus gene segment sequences to analyze the divergence date and vaccine strain match of human influenza A(H3N2) virus from systematic influenza surveillance in Hangzhou.

Methods: Virological and serological analyses of 124 representative A(H3N2) viruses from prospective studies of systematic surveillance samples were conducted to quantify the genetic and antigenic characteristics and their vaccine strain match.

[Molecular epidemiology of human metapneumovirus in children with respiratory tract infection in Hangzhou].

Objective: To understand the molecular epidemiologic features of human metapnenmovirus (hMPV) in children with respiratory tract infection in Hangzhou.

Methods: 2 593 throat swabs were collected from patients with respiratory tract infections who visited the hospitals with sentinel surveillance programs from January 2011 to December 2013, including 1 676 outpatients and 917 inpatients. Total nucleic acid was extracted from the specimens and the fusion (F) protein gene of hMPV was amplified by quantitative real-time reverse transcription polymerase chain reaction (RT-PCR), with positive samples picked to compare with the sequence of hMPV in GenBank, after the sequence of amplification products were determined.

Progressive antigenic drift and phylogeny of human influenza A(H3N2) virus over five consecutive seasons (2009-2013) in Hangzhou, China.

Vaccine efficacy (VE) can be affected by progressive antigenic drift or any new reassortment of influenza viruses. To effectively track the evolution of human influenza A(H3N2) virus circulating in Hangzhou, China, a total of 65 clinical specimens were selected randomly from outpatients infected by A(H3N2) viruses during the study period from November 2009 to December 2013. The results of reduced VE and antigenic drift of the correspondent epitopes (C-D-E to A-B) suggest that the current vaccine provides suboptimal protection against the A(H3N2) strains circulating recently.

Influenza H7N9 and H9N2 viruses: coexistence in poultry linked to human H7N9 infection and genome characteristics.

Unlabelled: Avian influenza virus A of the novel H7N9 reassortant subtype was recently found to cause severe human respiratory infections in China. Live poultry markets were suspected locations of the human H7N9 infection sources, based on the cases' exposure histories and sequence similarities between viral isolates. To explore the role of live poultry markets in the origin of the novel H7N9 virus, we systematically examined poultry and environmental specimens from local markets and farms in Hangzhou, using real-time reverse transcription-PCR (RT-PCR) as well as high-throughput next-generation sequencing (NGS).

[Analysis of infection status and pathogenic features of human metapneumovirus among children in Hangzhou between year 2009 and 2011].

Objective: To study the infection status and pathogenic features of human metapneumovirus (hMPV) among children with acute respiratory tract infection in Hangzhou.

Methods: A total of 372 children less than 14 years old with acute respiratory tract infections were recruited as subjects from the pediatric clinic or intensive care unit (ICU) of 3 hospitals in Hangzhou during November 2009 to January 2010, and November 2010 to January 2011. A total of 372 specimens were collected, including 351 respiratory swab, 9 nasopharyngeal aspirate material, 8 endotracheal aspirate material and 4 sputum.

Trimeric coiled-coil domain of human pulmonary surfactant protein D enhances zinc-binding ability and biologic activity of soluble TRAIL.

Unlike other TNF ligand family members, the homotrimeric tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) contains a buried zinc atom coordinated by three Cys230 residues from each subunit. The bound zinc ion is essential for maintaining the structure stability and bioactivity of TRAIL. To improve characteristics of TRAIL by modification to enhance its zinc-binding ability, we constructed a new variant of TRAIL in which the extracellular region of the ligand was N-terminally fused with a trimeric coiled-coil domain derived from human pulmonary surfactant-associated protein D (ST), and compared its characteristics with that of native TRAIL.