Publications by authors named "Xinfen Yu"

Article Synopsis
  • - Exposure to live poultry markets has traditionally been linked to human infections of avian influenza, but recent changes in consumer habits, particularly the shift to purchasing freshly slaughtered poultry, have not eliminated the risk.
  • - A reported case in Hangzhou involved a person infected with the H5N6 virus after handling freshly slaughtered chicken, indicating a potential new route of infection that deviates from previous assumptions that only live poultry exposure could cause infection.
  • - Genomic analysis showed that the H5N6 variants were avian in origin and adapting to humans, highlighting the complexity of viral contamination in environments like poultry markets and emphasizing the need for improved surveillance and awareness of risks from infected poultry.
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A human co-infected with H1N1 and H7N9 subtypes influenza A virus (IAV) causes a complex infectious disease. The identification of molecular-level variations in composition and dynamics of IAV quasispecies will help to understand the pathogenesis and provide guidance for precision medicine treatment. In this study, using single-molecule real-time sequencing (SMRT) technology, we successfully acquired full-length IAV genomic sequences and quantified their genotypes abundance in serial samples from an 81-year-old male co-infected with H1N1 and H7N9 subtypes IAV.

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The emergence of the influenza A(H1N1)pdm09 virus with the NA-H275Y mutation, which confers oseltamivir resistance, must be monitored, especially in patients undergoing neuraminidase inhibitor treatment. In this study, we developed a reverse transcription recombinase-aided amplification assay that has high sensitivity (detection limit: 1.0 × 10 copies/μL) and specificity for detecting the oseltamivir-resistant H275Y mutation; the assay is performed within 30 min at a constant temperature of 39° Celsius using an isothermal device.

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The novel SARS-CoV-2 outbreak has swiftly spread worldwide. The rapid genome sequencing of SARS-CoV-2 strains has become a helpful tool for better understanding the genomic characteristics and origin of the virus. To obtain virus whole-genome sequences directly from clinical specimens, we performed nanopore sequencing using a modified ARTIC protocol in a portable nanopore sequencer and validated a routine 8-h workflow and a 5-h rapid pipeline.

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Lead (Pb) is an important environmental pollutant. Oxidative stress and the inflammatory response have been postulated as mechanisms involved in lead-induced renal damage. Roxb.

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Article Synopsis
  • * A study using samples from H7N9-infected patients and their poultry/environment showed that virus adaptations, such as changing from the avian signature 627E to the mammalian signature 627K, occurred rapidly in human infections.
  • * This "genetic tuning" correlates with the severity of the disease and highlights the need to monitor the evolution of avian-origin influenza viruses during infections in humans.
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  • A large dengue outbreak in Hangzhou, China from July to November 2017 resulted in 1,138 mild indigenous cases, linked to independent introductions of at least three lineages of the dengue virus serotype 2 (DENV-2) Cosmopolitan genotype.
  • Phylogenetic analysis indicates these virus lineages may have emerged as early as March 2017, likely due to group travelers returning from dengue-endemic areas.
  • Contributing factors to the outbreak included the co-circulation of multiple DENV-2 lineages, urban disease emergence, favorable weather conditions for mosquito breeding, and limited diagnostic capabilities of local hospitals.
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Uric acid metabolic disorder is considered to be the main pathogenesis of uric acid nephropathy (UN). Smilax glabra Roxb. is a traditional Chinese herb which has been used in the treatment of gout, but the mechanism was unclear.

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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.

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Article Synopsis
  • - The study analyzed 1820 pediatric patients in Hangzhou to understand RSV prevalence and genetic variation during two epidemic seasons, discovering RSV in 34.5% of acute lower respiratory tract infections and 3.8% of influenza-like illnesses.
  • - Genetic testing revealed 61.1% of RSV strains were NA1, with the identification of a new genotype, BA11, representing the majority of BA strains, and significant co-infection rates of 36.4% and 9.1% in RSV-positive children with ALRI and ILI, respectively.
  • - The findings indicate high genetic diversity among circulating RSV strains, particularly RSV-B, and suggest that co-infection with other viruses does not substantially alter clinical
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  • The study examined the genetic diversity and evolution of the M gene in human influenza A viruses from 2009 to 2013 in Hangzhou, focusing on A(H1N1) pdm09 and seasonal A(H3N2) strains.
  • Out of 5675 throat swabs tested, the influenza virus was detected in 20.46%, with 827 cases identified as infections by influenza A viruses, and 76 strains selected for detailed genetic analysis.
  • The M gene showed high sequence similarity across different epidemics, with notable mutations indicating resistance and varied evolutionary pressures between the A(H1N1) and A(H3N2) viruses, which provides crucial insights for disease control measures.
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Unlabelled: The novel H7N9 avian influenza virus (AIV) was demonstrated to cause severe human respiratory infections in China. Here, we examined poultry specimens from live bird markets linked to human H7N9 infection in Hangzhou, China. Metagenomic sequencing revealed mixed subtypes (H5, H7, H9, N1, N2, and N9).

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Article Synopsis
  • Two children with distinct digestive diseases were hospitalized in Hangzhou, China, in May 2010.
  • While in the hospital, both children developed symptoms of an acute lower respiratory tract infection.
  • Evidence suggested that one child contracted a co-infection with measles virus and human metapneumovirus from the other while they were in the same ward.
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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.

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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.

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Influenza A (H7N9) virus has been causing human infections in China since February 2013, raising serious concerns of potential pandemics. Previous studies demonstrate that human infection is directly linked to live animal markets, and that the internal genes of the virus are derived from H9N2 viruses circulating in the Yangtze River Delta area in Eastern China. Here following analysis of 109 viruses, we show a much higher genetic heterogeneity of the H7N9 viruses than previously reported, with a total of 27 newly designated genotypes.

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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).

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A novel H7N9 influenza A virus has been discovered as the causative identity of the emerging acute respiratory infection cases in Shanghai, China. This virus has also been identified in cases of infection in the neighboring area Hangzhou City in Zhejiang Province. In this study, epidemiologic, clinical, and virological data from three patients in Hangzhou who were confirmed to be infected by the novel H7N9 influenza A virus were collected and analyzed.

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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.

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Background: Even under immune pressure, the highly active influenza A H1N1 pdm09 variants emerged again in December 2010. Did the variability lead to poor vaccine effectiveness?

Objectives: To study the genetic distance and antigenic drift of the influenza A H1N1 pdm09 strains based on the sequence analysis of HA virus gene segments during consecutive seasons 2009-2011 in Hangzhou, China.

Study Design: 39 Clinical samples from influenza-like-illness patients with culture-confirmed influenza A H1N1 pdm09 infections were collected over seasons in routine influenza surveillance.

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Adenovirus serotype 3 and 7 outbreaks have occurred periodically in northern, eastern, and southern China since 1955, but there has been no report since the adenovirus serotype 7 outbreak first occurred in Hangzhou, China, in 1991. Here we explored the epidemiology and etiology of two adenovirus serotype 3 outbreaks in Hangzhou in 2011. One acute respiratory outbreak was found in Chun'an County, where a total of 371 cases were confirmed in 5 of 23 towns from 4 to 31 May 2011.

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The total phenolic and flavonoid, antioxidant and antibacterial activities of six Sonchus wild vegetables (Sonchus oleraceus L., Sonchus arvensis L., Sonchus asper (L.

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