Relevance of Host Cell Surface Glycan Structure for Cell Specificity of Influenza A Viruses.

Influenza A viruses (IAVs) initiate infection via binding of the viral hemagglutinin (HA) to sialylated glycans on host cells. HA's receptor specificity towards individual glycans is well studied and clearly critical for virus infection, but the contribution of the highly heterogeneous and complex glycocalyx to virus-cell adhesion remains elusive. Here, we use two complementary methods, glycan arrays and single-virus force spectroscopy (SVFS), to compare influenza virus receptor specificity with virus binding to live cells. Unexpectedly, we found that HA's receptor binding preference does not necessarily reflect virus-cell specificity. We propose SVFS as a tool to elucidate the cell binding preference of IAVs, thereby including the complex environment of sialylated receptors within the plasma membrane of living cells.

Males as victims of intimate partner violence - results from a clinical-forensic medical examination centre.

Only few studies have reported on males as victims of intimate partner violence (IPV) so far. The aim of the present study is to analyse frequency and case characteristics of physical violence against male IPV victims examined in a clinical-forensic medical examination centre for victims of violence in Germany over an 11-year period, contributing to a better understanding of IPV in men. Male victims represented 6.2% of IPV cases (n = 167) with a median age of 40 years. Cases were reported to the police in 78.4% before medicolegal examination. In 60.5% of the cases, the perpetrator was the current partner, and 82% occurred in a domestic environment with a predominance of female offenders. In more than half of the cases (57.5%), the victims consulted the examination centre without prior healthcare utilisation. About one-third of the victims reported previous IPV (31.7%). The findings point to the relevance of men as victims of IPV, case group-specific risk factors, injury-dependent behaviour related to healthcare utilisation, the need to establish or strengthen specialised support services for affected men and underscore the importance of clinical-forensic services in documenting and assessing violence-related injuries.

Genetic characterization of an adapted pandemic 2009 H1N1 influenza virus that reveals improved replication rates in human lung epithelial cells.

The 2009 influenza pandemic originated from a swine-origin H1N1 virus, which, although less pathogenic than anticipated, may acquire additional virulence-associated mutations in the future. To estimate the potential risk, we sequentially passaged the isolate A/Hamburg/04/2009 in A549 human lung epithelial cells. After passage 6, we observed a 100-fold increased replication rate. High-throughput sequencing of viral gene segments identified five dominant mutations, whose contribution to the enhanced growth was analyzed by reverse genetics. The increased replication rate was pinpointed to two mutations within the hemagglutinin (HA) gene segment (HA1 D130E, HA2 I91L), near the receptor binding site and the stem domain. The adapted virus also replicated more efficiently in mice in vivo. Enhanced replication rate correlated with increased fusion pH of the HA protein and a decrease in receptor affinity. Our data might be relevant for surveillance of pre-pandemic strains and development of high titer cell culture strains for vaccine production.