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Photocatalytic Inactivation of Pathogenic Viruses Using Metal Oxide and Carbon-Based Nanoparticles
Published in Devarajan Thangadurai, Saher Islam, Charles Oluwaseun Adetunji, Viral and Antiviral Nanomaterials, 2022
Lan Ching Sim, Wei Qing Wee, Shien Yoong Siow, Kah Hon Leong, Jit Jang Ng, Pichiah Saravanan
Woo et al. (2012) designed a microwave-irradiation-assisted filtration system to inactivate viral aerosols, which can reach a high inactivation efficiency of around 5-log. Xia et al. (2019) demonstrated the efficacy of nonthermal plasma (NTP) against MS2 virus using a packed bed nonthermal plasma reactor. Approximately 2.3-log virus was reduced in which ~2-log of the MS2 inactivated and ~0.35-log physically removed in the packed bed. Wigginton et al. (2012) used five different disinfectants, such as free chlorine (FC), heat, UV irradiation, singlet oxygen, and chlorine dioxide (ClO2), to inactivate MS2 virus. They found that each treatment method resulted in a unique inactivation mechanism. For example, ClO2 or heat treatments may be suitable for inactivating double-stranded DNA viruses with genome repair mechanisms. UV treatment was more effective for inactivating single-stranded RNA viruses without genome repair mechanisms. Nonthermal plasma (NTP) produces chemically active species, such as atomic oxygen, hydroxyl radicals, and ozone, to remove bioaerosol. However, the production of toxic byproduct, such as CO, O3, NOX and aerosol particles, restricts its application (Yu et al. 2009). Other conventional methods like UV irradiation, thermal treatment, and microwave irradiation are not practical because they require high energy consumption. Therefore, heterogeneous photocatalysis has recently emerged as an alternative technology to the current viral inactivation since the foremost discovery by Sjogren and Sierka (1994).
Gene Therapy and Small Molecules Used in the Treatment of Cystic Fibrosis
Published in Yashwant Pathak, Gene Delivery, 2022
Manish P. Patel, Uma G. Daryai, Mansi N. Athalye, Praful D. Bharadia, Jayvadan Patel
Adenoviruses belong to the family Adenoviridae. These are nonenveloped, double-stranded DNA viruses composed of a complex icosahedral capsid (Volpers and Kochanek, 2004) and (Saban et al., 2006). Studies realized that the coxsackie and adenovirus receptor (CAR) receptors are located on the basolateral rather than the apical membrane of airway epithelial cells that led to assessment of tight junction openers, such as sodium caprate and lysophosphatidylcholines, which showed moderate success (Griesenbach, Pytel, and Alton, 2015). The knob domain of the fiber binds to the coxsackie and adenovirus receptor (CAR) on the cell surface and facilitates virus entry, (Volpers and Kochanek, 2004) although integrin receptors, such as αvβ3 and αvβ5 and the major histocompatibility complex (MHC) class I, may also play a role in virion–cell interaction. After arrival, the virus remains in an episomal state within the nucleus. In one research study, a serotype 2 adenoviral (Ad2) vector carrying the human CFTR cDNA was administrated nasally (Griesenbach, Pytel, and Alton, 2015).
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.
Myocarditis: causes, mechanisms, and evolving therapies
Published in Expert Opinion on Therapeutic Targets, 2023
Tin Kyaw, Grant Drummond, Alex Bobik, Karlheinz Peter
Herpesviruses: Herpesvirus is one of the most frequent causes of viral myocarditis. It is present in up to 36% of identified cases, frequently associated with acute and chronic heart failure [41]. Herpesviruses implicated in myocarditis include human herpesvirus 6 (HHV-6) [42], Epstein–Barr virus (EBV) [43], cytomegalovirus (CMV) [44], and varicella-zoster virus (VZV) [45]. Herpesviruses are enveloped double-stranded DNA viruses with an icosahedral capsid. The capsid is surrounded by an amorphous protein layer and an envelope containing viral glycoprotein spikes [46]. These viruses are complex and encode a large number of enzymes involved in nucleic acid metabolism, DNA synthesis, and processing of proteins. HHV-6 capsid maturation, DNA packaging, glycoprotein modification, and the formation of mature virus require the U53-encoded protease [47]; the protease has been sequenced and characterized and may be a possible therapeutic target [48]. HHV-6 comprises two variants HHV-6A and HHV-6B [43] but only HHV-6B seems pathogenic [49]. HVV-6B utilizes a number of strategies to reduce host immune responses, producing chemokines and chemokine receptors [50], downregulating ligands that trigger natural killer cell activation, ULBP1, MICB, and B7-H6 as well as downregulating MHC class I to attenuate anti-viral CD8+ T cell activation [49]; It also upregulates PD-L1 on the surface of infected monocytes further impairing anti-viral immunity [51].
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].