Clinical and Cytopathological Traits of Herpes Zoster: A Report of Two Cases

Introduction: Varicella zoster virus is a highly infectious alpha-herpesvirus, pathogenic only to humans. The primary infection of varicella zoster virus causes chickenpox, which is contagious and primarily infects children and adolescents in India. Following the primary infection, the virus remains dormant in sensory root ganglia. Activation of the dormant virus in later stages of life causes herpes zoster infection which may vary from subclinical infection to typical zoster, scattered vesicles, zoster sine herpete or disseminated zoster, which depends on the individual's immune status. Case report: In this case series, we present two patients with herpes zoster involving the mandibular branch of the trigeminal nerve. Cytology revealed characteristic features of the infection including nuclear moulding, multinucleated giant cells and ballooning degeneration. Conclusion(s): More recently, patients presenting with herpes zoster have been reported to have sub-clinical Covid-19 infection, suggesting a possibility that herpes zoster might be an indicator for latent Covid-19. Timely detection and treatment of this infection can reduce the risk of post herpetic neuralgia.Copyright © 2022 Sciendo. All rights reserved.

COVID-19: the CaMKII-like system of S protein drives membrane fusion and induces syncytial multinucleated giant cells.

The SARS-CoV-2 S protein on the membrane of infected cells can promote receptor-dependent syncytia formation, relating to extensive tissue damage and lymphocyte elimination. In this case, it is challenging to obtain neutralizing antibodies and prevent them through antibodies effectively. Considering that, in the current study, structural domain search methods are adopted to analyze the SARS-CoV-2 S protein to find the fusion mechanism. The results show that after the EF-hand domain of S protein bound to calcium ions, S2 protein had CaMKII protein activities. Besides, the CaMKII_AD domain of S2 changed S2 conformation, facilitating the formation of HR1-HR2 six-helix bundles. Apart from that, the Ca2+-ATPase of S2 pumped calcium ions from the virus cytoplasm to help membrane fusion, while motor structures of S drove the CaATP_NAI and CaMKII_AD domains to extend to the outside and combined the viral membrane and the cell membrane, thus forming a calcium bridge. Furthermore, the phospholipid-flipping-ATPase released water, triggering lipid mixing and fusion and generating fusion pores. Then, motor structures promoted fusion pore extension, followed by the cytoplasmic contents of the virus being discharged into the cell cytoplasm. After that, the membrane of the virus slid onto the cell membrane along the flowing membrane on the gap of the three CaATP_NAI. At last, the HR1-HR2 hexamer would fall into the cytoplasm or stay on the cell membrane. Therefore, the CaMKII_like system of S protein facilitated membrane fusion for further inducing syncytial multinucleated giant cells.