China
Africa
Explore chapters and articles related to this topic
Detection Assays and Techniques Against COVID-19
Published in Hanadi Talal Ahmedah, Muhammad Riaz, Sagheer Ahmed, Marius Alexandru Moga, The Covid-19 Pandemic, 2023
Shahzad Sharif, Maham Saeed, Javed Hussain Shah, Sajjad Hussain, Ahmad Adnan, Hanadi Talal Ahmedah, Muhammad Riaz
Diagnosis of RNA at an initial stage is also a big challenge. In comparison to all available techniques, nucleic acid-based tests and cell culture are being used as gold standards. DNA viruses have polymerase machinery while RNA has supplementary processes to go back from RNA to DNA formerly of its amplification. Viruses of SARS, COVID-19 and MERS correspond structurally to a homogenous type of “Beta Coronavirus” origin, which being globular, often multi-shapes [132]. Various properties of the above-mentioned viruses including average diameter are “125 nm,” capsid layer “85 nm” and surface diameter of “Spikes” is 20 nm. Early detection of COVID-19 may be done by correlating hereditary properties of SARS-CoV2 with other viruses.
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).
Antiviral Agents and Rational Drug Design
Published in Nathan Keighley, Miraculous Medicines and the Chemistry of Drug Design, 2020
In order to be able to identify targets against which drugs can be developed, knowledge of the structure and life cycle of viruses is paramount. A virus particle can simply be considered as a protein package that contains a type of nucleic acid with which it can infect host cells and hijack the host cell’s machinery to reproduce itself. Viruses contain one or more molecules of either RNA or DNA, but not both, thus are defined as either RNA viruses or DNA viruses. The RNA can be single-stranded (ssRNA) as is the case for most viruses, or double stranded, where the base sequence of the RNA that is the same as viral mRNA is called the (+) strand and its complementary partner is the (−) strand. Most DNA viruses contain the typical double stranded DNA, but single-stranded DNA is present in some viruses. There is great variation between viruses in the size of the nucleic acid, ranging from genomes coding for just three-to-four proteins to larger genomes that code for over one hundred proteins.
Comparative evaluation of the clinical presentation and epidemiology of the 2022 and previous Mpox outbreaks: a rapid review and meta-analysis
Published in Infectious Diseases, 2023
George N. Okoli, Paul Van Caeseele, Nicole Askin, Ahmed M. Abou-Setta
At present, there are no drugs approved specifically for the treatment of Mpox. The treatment is mostly supportive and aimed at prevention of long-term sequelae of the disease. Nevertheless, some antiviral drugs developed for use against smallpox may be beneficial against the Mpox and, based on limited data in humans, tecovirimat, which has specific activity against orthopoxviruses and works by inhibiting the formation of the extracellular enveloped virus necessary for cell-to-cell transmission has been mostly used although not widely available [19,20]. Antiviral drugs working as inhibitors of deoxyribonucleic acid (DNA) replication and having a broad spectrum of activity against many families of double-stranded DNA viruses, such as Cidofovir and its prodrug brincidovir [20], and vaccinia immune globulin have also been identified to be active against monkeypox virus and other orthopoxviruses, but are currently not as utilised as tecovirimat for Mpox treatment [21].
Prevalence of Epstein–Barr Virus in Patients with Intraocular Inflammation
Published in Ocular Immunology and Inflammation, 2023
Kareem Moussa, John A. Gonzales, Jessica Shantha, Nisha R. Acharya, Thuy Doan
Given that the majority of adults have detectable EBV antibodies in the plasma, one may predict that the detection of EBV genomic material in ocular fluid is to be expected, as lymphocytes serve as host cells for EBV, and the breakdown of the blood ocular barrier in uveitis leads to infiltration of these lymphocytes into the eye. In this study, RNA-seq was used to comprehensively detect pathogens. The presence of RNA copies of a DNA virus, such as EBV, suggests active replication of the virus. Furthermore, in a separate study of 11 HIV-negative immunocompromised patients with uveitis, out of which 6 had EBV DNA detected in ocular fluid by PCR, only 1 patient had EBV DNA detected in serum by PCR, arguing against the possibility that EBV DNA detected in the eye is due to “overflow” from the peripheral circulation.6 The use of EBV-directed PCR on intraocular fluid is rarely done for patients with intraocular inflammation as its utility is unclear. However, our results suggest that EBV RNA testing may serve an adjunctive role when the suspicion of vitreoretinal lymphoma is high on the differential.
Oncolytic virus therapy for malignant gliomas: entering the new era
Published in Expert Opinion on Biological Therapy, 2023
Hirotaka Fudaba, Hiroaki Wakimoto
Seven OV platforms are currently under clinical investigation in neuro-oncology and comprised of both DNA and RNA viruses. DNA viruses include herpes simplex virus-1 (HSV-1), adenovirus, vaccinia virus, and parvovirus. As RNA viruses, poliovirus, reovirus, and measles virus are being tested in brain tumor clinical trials. In general, both DNA and RNA viruses have their own set of pros and cons when it comes to properties as OVs. DNA viruses are relatively easy to genetically modify because of their larger and more stable genome [5]. RNA viruses are potentially non-persistent, making them highly suitable as OVs while minimizing safety concerns [6]. The genome size of RNA viruses is typically smaller than DNA viruses, which may contribute to their ability to penetrate the blood-brain barrier (BBB) [5].