Structure-guided pharmacophore based virtual screening, docking, and molecular dynamics to discover repurposed drugs as novel inhibitors against endoribonuclease Nsp15 of SARS-CoV-2.

COVID-19 (Corona Virus Disease of 2019) caused by the novel 'Severe Acute Respiratory Syndrome Coronavirus-2' (SARS-CoV-2) has wreaked havoc on human health and the global economy. As a result, for new medication development, it's critical to investigate possible therapeutic targets against the novel virus. 'Non-structural protein 15' (Nsp15) endonuclease is one of the crucial targets which helps in the replication of virus and virulence in the host immune system. Here, in the current study, we developed the structure-based pharmacophore model based on Nsp15-UMP interactions and virtually screened several databases against the selected model. To validate the screening process, we docked the top hits obtained after secondary filtering (Lipinski's rule of five, ADMET & Topkat) followed by 100 ns molecular dynamics (MD) simulations. Next, to revalidate the MD simulation studies, we have calculated the binding free energy of each complex using the MM-PBSA procedure. The discovered repurposed drugs can aid the rational design of novel inhibitors for Nsp15 of the SARS-CoV-2 enzyme and may be considered for immediate drug development.

Short Research Communication Anti-Spike Antibody Response to COVISHIELD™ (SII-ChAdOx1 nCoV-19) Vaccine in Patients with B-Cell and Plasma Cell Malignancies and Hematopoietic Cell Transplantation Recipients.

Introduction: There is limited data on the serologic antibody responses after the ChAdOx1 vaccine in patients with hematological malignancies and hematopoietic cell transplantation recipients. There is no data on the safety and efficacy of the Indian COVISHIELD™ vaccine in this population. Methods: This study reports the anti-S antibody response to the COVISHIELD™ vaccine in a prospective cohort of patients with B-cell and plasma cell malignancies and HCT recipients at a single center. The quantitative antibodies to the SARS-CoV-2 S protein receptor-binding domain in human plasma were determined by the validated Roche Elecsys Anti-SARS-CoV-2 S kit. Results: A total of 118 patients were included over the study period from April 2021 to August 2021. The seropositivity rate at baseline and after the first and second dose of the vaccine was 39%, 66%, and 79%, respectively (p < 0.0001). The seronegative cohort had a higher median age (65 vs. 60 years, p = 0.03), were more likely to be males (81% vs. 42%, p = 0.009), had a diagnosis of B-CLPD (100% vs. 42%, p < 0.001) and were more likely to be on ibrutinib therapy (56% vs. 15%, p = 0.001). Conclusions: This study confirms the safety and efficacy of the COVISHIELD™ vaccine in patients with hematological malignancies.

Integrative multiomics and in silico analysis revealed the role of ARHGEF1 and its screened antagonist in mild and severe COVID-19 patients.

COVID-19 is a sneaking deadly disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The rapid increase in the number of infected patients worldwide enhances the exigency for medicines. However, precise therapeutic drugs are not available for COVID-19; thus, exhaustive research is critically required to unscramble the pathogenic tools and probable therapeutic targets for the development of effective therapy. This study utilizes a chemogenomics strategy, including computational tools for the identification of viral-associated differentially expressed genes (DEGs), and molecular docking of potential chemical compounds available in antiviral, anticancer, and natural product-based libraries against these DEGs. We scrutinized the messenger RNA expression profile of SARS-CoV-2 patients, publicly available on the National Center for Biotechnology Information-Gene Expression Omnibus database, stratified them into different groups based on the severity of infection, superseded by identification of overlapping mild and severe infectious (MSI)-DEGs. The profoundly expressed MSI-DEGs were then subjected to trait-linked weighted co-expression network construction and hub module detection. The hub module MSI-DEGs were then exposed to enrichment (gene ontology + pathway) and protein-protein interaction network analyses where Rho guanine nucleotide exchange factor 1 (ARHGEF1) gene conjectured in all groups and could be a probable target of therapy. Finally, we used the molecular docking and molecular dynamics method to identify inherent hits against the ARHGEF1 gene from antiviral, anticancer, and natural product-based libraries. Although the study has an identified significant association of the ARHGEF1 gene in COVID19; and probable compounds targeting it, using in silico methods, these targets need to be validated by both in vitro and in vivo methods to effectively determine their therapeutic efficacy against the devastating virus.

COVID-19 Outbreak: Neurological Manifestations Beyond Cough and Fever.

COVID-19 is one of the most disastrous respiratory diseases (after the 1918 influenza outbreak) spreading in the community. So far, it has killed 7,37,417 individuals. High variability in the viral genome and its greater ability to spread in the human community are badly affecting the comorbid individuals. Although infected individuals mainly possess respiratory issues, neurological manifestations in these individuals cannot be overlooked. The literature search is based on the recent development in the concerned field. We searched databases like PubMed, Google Scholar, and ScienceDirect using the keywords "COVID-19", "neurological manifestations", "CNS", and "PNS". The major neurological complications observed in these patients are encephalitis, necrotising haemorrhagic encephalopathy, Guillain-Barré Syndrome, smell/taste impairment, epileptic seizures, and abnormal states of consciousness. COVID-19 infection is just more than a cough, fever, and respiratory illness; it can cause indirect neurological complications in infected patients. It is therefore advised to treat and have a careful observation of the COVID-19 patients for neurological manifestations.