Synergistic Interactions between the NS3hel and E Proteins Contribute to the Virulence of Dengue Virus Type 1

Dengue virus constitutes a significant public health problem in tropical regions of the world. Despite the high morbidity and mortality of this infection, no effective antiviral drugs or vaccines are available for the treatment or prevention of dengue infections. The profile of clinical signs associated with dengue infection has changed in recent years with an increase in the number of episodes displaying unusual signs. We use reverse genetics technology to engineer DENV-1 viruses with subsets of mutations previously identified in highly neurovirulent strains to provide insights into the molecular mechanisms underlying dengue neuropathogenesis. We found that single mutations affecting the E and NS3hel proteins, introduced in a different genetic context, had a synergistic effect increasing DENV replication capacity in human and mosquito derived cells in vitro. We also demonstrated correlations between the presence of these mutations and viral replication efficiency, viral loads, the induction of innate immune response genes and pathogenesis in a mouse model. These results should improve our understanding of the DENV-host cell interaction and contribute to the development of effective antiviral strategies

GAP waveguides

The coming years will show new applications of wireless communications at higher frequencies (30 GHz and above). Modern wireless technologies like massive MIMO and gigabit transmission will become a reality. The industrial winners will be the companies that can provide the hardware at the lowest cost. This requires new waveguide and mmWave packaging technologies that are more cost-effective than normal rectangular waveguide technology and are more power efficient (lower losses) than PCB-based microstrip and coplanar waveguides. The gap waveguide has this potential. The present chapter gives the historical background of gap waveguide technology until its invention in 2008 and how it has evolved since then to include many different kinds of gap waveguide types. Several useful waveguide components have been developed for integration in complete RF front ends. Passive gap waveguide parts and components like filters, couplers, and transitions have been realized very successfully, and active microwave electronics have been packaged. The chapter contains also an overview of the gap waveguide antennas that have been developed during the last years