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A Case Of Varicella-Zoster Virus In A Maternity Unit
Published in Meera Chand, John Holton, Case Studies in Infection Control, 2018
Michelle Griffin, Meera Chand, Kevin E Brown
The virus is a double-stranded DNA virus, surrounded by a lipid-containing envelope with glycoprotein spikes. There are approximately 125,000 base pairs in the DNA, encoding approximately 75 proteins and 7 different glycoproteins (gB, gC, gE, gH, gI, gK, and gL). Neutralizing antibodies and the cell-mediated responses are predominantly targeted toward the glycoproteins.
Prospective Therapies of Genital Human Papillomavirus Infections
Published in Satya Prakash Gupta, Cancer-Causing Viruses and Their Inhibitors, 2014
Ricardo Ney Oliveira Cobucci, Janaina Cristiana de Oliveira Crispim, Ana Katherine da Silveira Gonçalves
The taxonomy of 120 papillomaviruses has been described using sequence comparisons of the L1 ORF. There are 16 genotypes of papillomaviruses categorized. The alpha and beta genotypes contain the largest number of associated papillomaviruses. All HPVs have a special affinity for epithelial cells, and infection persists in the dividing basal cells of the cutaneous or mucosal epithelium. The small, circular, double-stranded DNA virus naturally exists episomally and has the ability to cause a wide range of lesions in humans. Papillomaviruses are characteristically epitheliotropic and cause proliferative lesions in infected epidermal or mucosal epithelia. They are commonly designated wart viruses, although many members of the group induce only discrete lesions that differ histologically from common warts. Certain types may cause benign and certain types may cause malignant tumors (Berkhout et al. 1995).
Head and Neck
Published in Adnan Darr, Karan Jolly, Jameel Muzaffar, ENT Vivas, 2023
Hannah Nieto, Theofano Tikka, Adnan Darr, Karan Jolly, Paul Pracy, Vinidh Paleri
Background: 95% SCC, lymphomaTonsil most common. Tongue base: HPV most common cause. Poorer prognosis and more aggressive if HPV negative Double-stranded DNA virus, which infects stratified squamous epithelium. Type 16 most commonL1 (capsid protein of HPV) and L2 are proteins that encapsulate viral particleE6 and E7 are proto-oncogenes responsible for anogenital and H&N cancers protein binds to and inactivates p53 tumour suppressor protein protein binds to and inactivates Rb protein. Degradation of Rb protein is linked to p16 overexpression, which is used as a surrogate marker of HPV related SCC.Not all p16 +ve results means HPV infection (10–20% not HPV +ve), p16 positivity in >70% of cells for confirmationImproved overall survival and decreased loco-regional failure. Younger patients and non-smokersStaging adjusted to downgrade overall stage to reflect improved survival despite more advanced disease with wider lymphadenopathy spreadPrognosis: HPV + non-smoker > HPV + smoker, HPV− and non-smoker > HPV− and smokerNon-HPV oropharyngeal (OPC) staging: Addition on TNM 8HPV + OPV:
Relationship between vaginal microecological changes and oncogene E6/E7 and high-risk human papillomavirus infection
Published in Journal of Obstetrics and Gynaecology, 2023
Jun Huang, Cunsi Yin, Junli Wang
HPV is a small, circular, double-stranded DNA virus whose several subtypes are distinctively classified into low-risk (LR) and high-risk (HR) groups (Medeiros et al. 2020). Additionally, treatment of almost all LR-HPV infections and more than two-thirds of HR-HPV infections can eradicate the infection within 24 months, and only a small proportion of women infected with HPV develop CC (Gravitt 2011). Chronic infection with HR-HPV is a vital cause of CC and precancerous lesions (Rajendra and Sharma 2019). The pathogenesis of HPV infection principally involves overexpression of viral oncoprotein, which can inhibit various cellular proteins and affect biological processes including cell proliferation, cell cycle, and apoptosis (Balasubramaniam et al. 2019). The HPV genome comprises six early genes E1, E2, E4, E5, E6, and E7, and two late genes L1 and L2, encoding the capsid protein (Ruttkay-Nedecky et al. 2013). Among the early genes, E6 and E7 are terminally carcinogenic by inactivation of the tumour suppressor protein p53 and retinoblastoma protein (Rb), respectively (Liu et al. 2018). An existing study by Chai et al. documented a high expression of E6/E7 mRNA in HPV-infected tonsil squamous cell carcinoma (Chai et al. 2015). Additionally, rutin can essentially induce caspase-dependent apoptosis of CC HeLa cells through HPV-E6 and E7 downregulation to elicit an anticancer effect (Pandey et al. 2021). Therefore, further investigation into the relationship between E6/E7 and CC is of vital significance for the prevention and treatment of CC.
CARMIL2 Immunodeficiency with Epstein Barr Virus Associated Smooth Muscle Tumor (EBV-SMT). Report of a Case with Comprehensive Review of Literature
Published in Fetal and Pediatric Pathology, 2022
Mukul Vij, Meena Sivasankaran, Dhaarani Jayaraman, Srinivas Sankaranarayanan, Vimal Kumar, Deenadayalan Munirathnam, Julius Scott
EBV is a member of the γ subfamily of herpesvirus that preferentially infects oropharyngeal epithelial cells and B immune cells to establish lifelong latency in humans [17]. The linear, double-stranded DNA virus has more than 100 genes, of which only a subset is relevant in transformation and replication: the LMP, the EBV nuclear antigens (EBNA), EBER, and RNAs originating from the BamHI site [18]. CD21 molecule on the surface of the B cell serves as the virus receptor, binding the major viral envelope glycoprotein, gp350 [19]. EBV can cause ectopic infections and has been found in NK, T, gastric epithelial, and smooth muscle cells as well [20]. While EBV infection is mostly asymptomatic in children, ∼ 10 to 30% of adolescents develop infectious mononucleosis (IM) [21]. EBV infection has also been associated with autoimmune disorders, malignant lymphoma, hemophagocytic lymphohistiocytosis (HLH) and epithelial malignancies [19, 20]. Despite this association, most healthy individuals remain largely unaffected by EBV infection resulting from host cellular immune response that plays a major role in controlling initial EBV infection, viral replication and immune pathology, and subsequent immune surveillance that maintains EBV in a latent state [21].
Human oncogenic viruses: an overview of protein biomarkers in viral cancers and their potential use in clinics
Published in Expert Review of Anticancer Therapy, 2022
HPV is a small, unenveloped, circular, double-stranded DNA virus. Although more than 100 HPV types have been characterized today, the identified HPV types differ according to their oncogenic potential (low- and high-risk types). While low-risk HPV types cause benign lesions, high-risk HPV types cause malignant tumors [77]. Among those, 15-HPV types are known to be carcinogenic (i.e. high risk) [78]. HPV-16 and −18 are the most prevalent high-risk HPV types among the 15 high-risk types. Among the HPVs encoding 8 proteins, the oncoproteins E6 and E7 stand out due to their important contribution to the progression of HPV-induced cancers [79]. The most important function of E6 is to inhibit apoptosis and cause cell immortalization by degrading p53, while the most important function of E7 is to inhibit pRB by binding it, and cause of uncontrolled cell proliferation in cancer cells [80,81]. According to WHO, HPV is the most common sexually transmitted viral infection worldwide [82].