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Viral and Bacterial Infection Prevention Through Intentional Design
Published in AnnaMarie Bliss, Dak Kopec, Architectural Factors for Infection and Disease Control, 2023
Debra Harris, Denise N. Williams
Viruses are the smallest microbes, and they cannot reproduce without first infecting and reprogramming the machinery of host cells.35 Viruses have simple compositions and may be enveloped or nonenveloped. Enveloped viruses – such as coronavirus, hepatitis B and C, herpesvirus, human immunodeficiency virus, and influenza – have an external membrane composed of a phospholipid bilayer with glycoproteins. Nonenveloped viruses – such as adenovirus, calicivirus, enterovirus, hepatitis A, norovirus, polio, rhinovirus, and rotavirus – do not have a viral envelope and are hardier and more resistant to many antiviral compounds. Viruses are typically present in the human body at the ratio of about 13 viral cells to 1 human cell and may be integrated into regular bodily functions.2,36 Some viruses simply coexist with us, some help keep down the loads of invading pathogens, and others are pathogenic themselves but can persist at loads too low to cause illness or disease.
Animal Connection Challenges
Published in Michael Hehenberger, Zhi Xia, Huanming Yang, Our Animal Connection, 2020
Michael Hehenberger, Zhi Xia, Huanming Yang
An important concept for viral classification is the “viral envelope.” Many viruses have envelopes covering their protective protein capsid, i.e., the protein shell of a virus, enclosing the genetic material of the virus. The envelopes typically are derived from portions of the host cell membranes (phospholipids and proteins), but may include some viral glycoproteins.b Viral envelopes are essential for providing the entry into host cells. They may even help viruses to avoid the host immune system. Glycoproteins on the surface of the envelope serve to identify and bind to receptor sites on the host’s membrane. The viral envelope then fuses with the host’s membrane, allowing the capsid and viral genome to enter and infect the host. Figure 8.2 shows the viral envelope for the Cytomegalovirus, a member of the viral family known as Herpesviridae or herpesviruses. Herpesviruses like CMV (frequently associated with the salivary glands) share a characteristic ability to remain latent within the body over long periods.
Biology of Coronaviruses with Special Reference to SARS-CoV-2
Published in Joystu Dutta, Srijan Goswami, Abhijit Mitra, COVID-19 and Emerging Environmental Trends, 2020
Joystu Dutta, Srijan Goswami, Abhijit Mitra
As shown in Figure 2.2, the viral envelope is present just under the surface proteins, which is the outermost layer of the virus derived from the host cell membrane. Since the host cell membrane is made up of phospholipids and proteins, the fundamental composition of the viral envelope is as same as the host cell membrane. The only difference is that in viruses, these membrane structures are incorporated with viral glycoproteins instead of host cell glycoproteins (Chan et al., 2020). The phospholipid–protein complex of the viral envelope gets denatured when treated with soap, which in turn destroys the virus. This is the reason that the World Health Organization recommended thorough handwashing with soap as an important preventive measure.
Repurposing pharmaceutical excipients as an antiviral agent against SARS-CoV-2
Published in Journal of Biomaterials Science, Polymer Edition, 2022
Manisha Malani, Prerana Salunke, Shraddha Kulkarni, Gaurav K. Jain, Afsana Sheikh, Prashant Kesharwani, Jayabalan Nirmal
Enveloped viruses such as influenza virus and coronavirus infects host cell by binding to cellular receptors, thereby, resulting in fusion host cell membrane and viral envelope [119]. Evidence suggests that cholesterol present in micro domains of the viral envelope and host cell membrane is prerequisite for the triumphant entry of virus into the host cell [120]. Cyclodextrins and modified cyclodextrins are involved in sequestering cholesterol from viral envelope, including lipid rafts comprising mainly of cholesterol. This leads to disruption of lipid rafts and ultimately structural deformation of the virus [121]. Cyclodextrins can also act on host cell and deplete cholesterol from their membranes, providing them less susceptible to viral attack. Methylated beta-cyclodextrin (MβCD) is known to impair influenza A and Coronavirus infection by cholesterol depletion [122].
Critical Review and Research Needs of Ozone Applications Related to Virus Inactivation: Potential Implications for SARS-CoV-2
Published in Ozone: Science & Engineering, 2021
Christina Morrison, Ariel Atkinson, Arash Zamyadi, Faith Kibuye, Michael McKie, Samantha Hogard, Phil Mollica, Saad Jasim, Eric C. Wert
Ozone has received increased attention for use against viruses due to its strong disinfection abilities. In general, viruses consist of a nucleic acid genome (DNA or RNA) coated by a protein comprised nucleocapsid. Some viruses, such as SARS-CoV-2, additionally maintain a viral envelope comprised lipids and proteins from its host cell membrane as its outermost layer. Enveloped viruses have long been assumed to exhibit decreased environmental persistence when compared to non-enveloped viruses, which has resulted in their omission in many environmental-related disinfection studies (Wigginton, Ye, and Ellenberg 2015).
Design of an effective piezoelectric microcantilever biosensor for rapid detection of COVID-19
Published in Journal of Medical Engineering & Technology, 2021
Hannaneh Kabir, Mohsen Merati, Mohammad J. Abdekhodaie
COVID-19 is one type of coronaviruses with RNA-positive strands which has emerged as a devastating infectious disease. COVID-19 molecular weight is about (5.5 to 6.1) *106 and its diameter is placed in the range of 75 to 160 nanometres. It is described as a spherical crown-like shape virus with some projections on its envelope [27]. The envelope contains a lipid bilayer membrane with four types of structural proteins; Membrane protein (M) which is the predominant one, Nucleocapsid protein (N), Spike glycoprotein (S) which adheres to host cells and interacts with Angiotensin-Converting Enzyme 2 (ACE2) receptors and Envelope small protein (E) (Figure 3) [28]. E and M proteins have essential roles in assembling the viral particles. Previous studies showed that N protein is beneficial to be applied as a diagnostic antigen due to its relatively conservative property in coronavirus structure. It plays an important role in viral pathogenesis, replication, and RNA packaging [29]. COVID-19 infects target cells through its spike antigen binding to ACE2 receptors expressed on different cells of tissues. It attaches to ACE2 receptors on epithelial cells of the nasopharyngeal region and type2 pulmonary cells in the lower respiratory tracts. Viral envelope fuses with the cell membrane of host cells which results in the release of viral RNA into the host cells and eventually its replication [13,28,30]. Based on the neutralising property of the anti-S protein antibody, it has the potential to be utilised for diagnosing the disease and designing the vaccines. It is the major transmembrane protein of COVID-19 and has higher immunogenicity than the others [13,17]. Regarding the mentioned features, S protein has been considered the major antigen that binds to the coated antibodies on the biosensor surface.