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Algae as a Source of Polysaccharides and Potential Applications
Published in Sanjeet Mehariya, Shashi Kant Bhatia, Obulisamy Parthiba Karthikeyan, Algal Biorefineries and the Circular Bioeconomy, 2022
Sonal Tiwari, E Amala Claret, Vikas S. Chauhan
Polysaccharides derived from the red alga Gelidium robustum protect embryonic eggs against the mumps virus and influenza B (Gerber et al., 1958). Sulfated polysaccharides (SPs) have been found to hinder the reproduction of enveloped viruses. Before infection, viruses must make contact with cell membrane glycosaminoglycan receptors (GAG), such as heparin sulfate (HS), to enter their host cell. SPs are negatively charged polymers and are chemically identical to HS. SPs hinder viral particle attachment by forming virus-algal PS complex by imitating GAG, eventually protecting the cell from infection (De Jesus Raposo et al., 2015). Carrageenan nasal spray exhibits considerable antiviral activity against three virus subgroups, HRV, human coronavirus, and influenza A virus, with the most significant efficacy reported in patients infected with the human coronavirus (Koenighofer et al., 2014). Polyguluronate sulfate (PGS), a low molecular weight sulfated brown algal polysaccharide, can block the production and secretion of hepatitis B surface antigens HBsAg and HBeAg (Chen et al., 2020). Sulfated polysaccharides from algae might be used as antiviral therapeutics against SARS-CoV-2 (Pereira and Critchley, 2020).
Novel RNA Interference (RNAi)-Based Nanomedicines for Treating Viral Infections
Published in Dan Peer, Handbook of Harnessing Biomaterials in Nanomedicine, 2021
Nyree Maes, Skye Zeller, Priti Kumar
Influenza viruses are of the family Orthomixoviridae that have a negative sense segmented RNA genome. Influenza A and B contain eight gene segments that are enclosed in an envelope composed of hemagglutanin (HA) neuraminidase (NA) and matrix 2 (M2) proteins. In addition, the genome encodes three components of the viral RNA-dependent RNA polymerase (RdRp): polymerase acidic protein (PA), polymerase basic protein 1 (PB1) and PB2, nucleoprotein (NP), and two non-structural proteins: NS1A and NS2. While Influenza B and C have a limited host tropism, Influenza A can infect a variety of mammals and is thus a major public health concern. Categorization of Influenza A is determined by the antigenic HA and NA subtypes that drift in prevalence from year to year escaping existing immune defenses and limiting the effectiveness of prophylactic vaccines. Approaches targeting conserved regions of Influenza A genes, such as those afforded by RNAi, could provide broad protection from potentially pandemic strains.
Bio-Nanoparticles: Nanoscale Probes for Nanoscale Pathogens
Published in Klaus D. Sattler, st Century Nanoscience – A Handbook, 2020
Mohamed S. Draz, Yiwei Tang, Pengfei Zhang
Because polymers can be readily made in large quantities with precise control over their structural and functional properties, they are uniquely versatile precursors for nanoparticle synthesis. Polymer nanoparticles with well-defined colloidal and surface characteristics have attracted considerable recent interest as superior building blocks for nanostructures [168,169]. In the biosensing field, these nanoparticles are frequently used as nanoscale detection platforms. In particular, polymer nanoparticle systems rely on immunological recognition reactions between an antigen and an antibody or on the hybridization of two complementary DNA single strands. The high surface-to-volume ratio and good structural and morphological controllability of polymer nanoparticles make them ideal uniform platforms for virus sensing with enhanced immobilization and bioconjugation capacity [170]. The remarkable encapsulation capability of polymer materials is another prominent feature of polymer nanoparticles that is of great interest in biosensing applications. Polymer nanoparticle encapsulants are currently used to enhance the photonic and chemical stability of different fluorescent dyes and to enhance signal amplification by increasing the number of impregnated dye molecules [144,171]. A variety of polymer nanoparticles for detection purposes have been prepared. Among them, styrene/acrylic acid copolymer nanoparticles that were impregnated with ArcaDia BF 530 dye and that carried influenza B virus antibodies were used to improve influenza B virus detection performance in a fluorescent nanoparticle tracer-based approach [126]. Fluorescent carboxylated polystyrene nanoparticles (mean diameter, ˜92 nm; Dragon Green dye, excitation 480 nm, emission 520 nm) were also conjugated with a gp120 monoclonal antibody specific for HIV [124].
Effects of life-stage and passive tobacco smoke exposure on pulmonary innate immunity and influenza infection in mice
Published in Journal of Toxicology and Environmental Health, Part A, 2022
Lei Wang, Maya Rajavel, Ching-Wen Wu, Chuanzhen Zhang, Morgan Poindexter, Ciara Fulgar, Tiffany Mar, Jasmine Singh, Jaspreet K. Dhillon, Jingjing Zhang, Yinyu Yuan, Radek Abarca, Wei Li, Kent E. Pinkerton
A mouse model was used in the present study. Since mice are not natural hosts for influenza viruses, influenza test strains were adapted to more efficiently attach to alveolar and epithelial cells in bronchi, replicate, suppress immunity, and exhibit virulence in the mouse (Kamal, Katz, and York 2014). The adaptation of the virus via engineered mutations makes the lung pathology of the mouse model similar to that of humans (Ilyushina et al. 2010). Murine-adapted strains influenza virus strains include influenza A/Puerto Rico/8/34, influenza A/WSN/33, and influenza B/Lee/1940 (Radigan et al. 2015). It was reported that with sufficiently large viral load inoculation, infection of BALB/c mice with the influenza A/Puerto Rico/8/34 viral strain results in severe pneumonia and increased mortality rates (Radigan et al. 2015). To study an animal model moderately infected by murine-adapted viruses might help to elucidate more comprehensively the biology of viral infection and host immune responses.
Influenza virus RNA recovered from droplets and droplet nuclei emitted by adults in an acute care setting
Published in Journal of Occupational and Environmental Hygiene, 2019
Lily Yip, Mairead Finn, Andrea Granados, Karren Prost, Allison McGeer, Jonathan B. Gubbay, James Scott, Samira Mubareka
Four and nine patient participants were infected with influenza A(H3N2) and influenza A(H1N1) viruses respectively; three participants were infected with influenza B virus. There was insufficient MT sample for quantification from one patient with influenza A(H1N1) virus and one patient with influenza B virus. The mean and median log10 copies/mL for MT swab viral load in patients with available samples was 4.08 (SD 2.39) and 4.13 (IQR 2.93–6.08) respectively. In patients with positive influenza A virus swabs, the mean and median log10 copies/mL for MT swab viral load were 4.71 (SD 2.21) and 4.83 (IQR 2.98–6.12). In patients with swabs positive for influenza A(H1N1) virus, the mean and median MT swab viral loads were 4.79 (SD 2.37) and 4.83 (IQR 3.85–6.12) log10 copies/mL. The mean and median MT swab viral load in patients with influenza A(H3N2) were identical at 4.32 (SD 1.97, IQR 2.93–5.71) log10 copies/mL. Finally, the mean and median MT swab viral load in patients with positive influenza B virus swabs was 1.78 (SD 1.60) and 2.24 (IQR 0–3.11) log10 copies/mL. There was no statistically significant difference between MT viral load and age, sex, number of symptoms, pharyngitis, need for oxygen, vaccination status, smoking status, or chest X-ray changes. However, there was a statistically significant association between higher viral load and fever (p-value 0.032).
Assessment of environmental and surgical mask contamination at a student health center — 2012–2013 influenza season
Published in Journal of Occupational and Environmental Hygiene, 2018
Steven H. Ahrenholz, Scott E. Brueck, Ana M. Rule, John D. Noti, Bahar Noorbakhsh, Francoise M. Blachere, Marie A. de Perio, William G. Lindsley, Ronald E. Shaffer, Edward M. Fisher
Other investigators have encountered varying degrees of success with surface sampling for influenza and other viruses. Bright et al.[27] sampled classroom surfaces including student desktops, faucet handles, water fountain toggle, and entrance doorknob for influenza Type A viruses. 24% (13/54) of the samples contained influenza virus with student desktops providing the most positive results (five of 27 desktops). Similarly, fomite swabbing was included in a human influenza challenge study by Killingley et al.[19] to assess person-to-person transmission. Nine of 48 fomite samples (19%) were PCR positive for influenza virus. An additional study by Killingley et al.[20] included 671 surface swabs collected at 39 separate locations in houses and hospital rooms. Thirty-three (4.9%) of the surface swabs detected influenza Type A(H1N1) pandemic 2009 by PCR. However, similar to our study, Tang et al.[26] were unable to detect influenza virus RNA on surfaces that were contaminated via direct cough by subjects with confirmed influenza. The PCR primers used were specific for influenza A, not influenza B that dominated the latter part of the 2012–2013 influenza season.[16]