Elucidation of novel compounds and epitope-based peptide vaccine design against C30 endopeptidase regions of SARS-CoV-2 using immunoinformatics approaches.

There has been progressive improvement in immunoinformatics approaches for epitope-based peptide design. Computational-based immune-informatics approaches were applied to identify the epitopes of SARS-CoV-2 to develop vaccines. The accessibility of the SARS-CoV-2 protein surface was analyzed, and hexa-peptide sequences (KTPKYK) were observed having a maximum score of 8.254, located between amino acids 97 and 102, whereas the FSVLAC at amino acids 112 to 117 showed the lowest score of 0.114. The surface flexibility of the target protein ranged from 0.864 to 1.099 having amino acid ranges of 159 to 165 and 118 to 124, respectively, harboring the FCYMHHM and YNGSPSG hepta-peptide sequences. The surface flexibility was predicted, and a 0.864 score was observed from amino acids 159 to 165 with the hepta-peptide (FCYMHHM) sequence. Moreover, the highest score of 1.099 was observed between amino acids 118 and 124 against YNGSPSG. B-cell epitopes and cytotoxic T-lymphocyte (CTL) epitopes were also identified against SARS-CoV-2. In molecular docking analyses, -0.54 to -26.21 kcal/mol global energy was observed against the selected CTL epitopes, exhibiting binding solid energies of -3.33 to -26.36 kcal/mol. Based on optimization, eight epitopes (SEDMLNPNY, GSVGFNIDY, LLEDEFTPF, DYDCVSFCY, GTDLEGNFY, QTFSVLACY, TVNVLAWLY, and TANPKTPKY) showed reliable findings. The study calculated the associated HLA alleles with MHC-I and MHC-II and found that MHC-I epitopes had higher population coverage (0.9019% and 0.5639%) than MHC-II epitopes, which ranged from 58.49% to 34.71% in Italy and China, respectively. The CTL epitopes were docked with antigenic sites and analyzed with MHC-I HLA protein. In addition, virtual screening was conducted using the ZINC database library, which contained 3,447 compounds. The 10 top-ranked scrutinized molecules (ZINC222731806, ZINC077293241, ZINC014880001, ZINC003830427, ZINC030731133, ZINC003932831, ZINC003816514, ZINC004245650, ZINC000057255, and ZINC011592639) exhibited the least binding energy (-8.8 to -7.5 kcal/mol). The molecular dynamics (MD) and immune simulation data suggest that these epitopes could be used to design an effective SARS-CoV-2 vaccine in the form of a peptide-based vaccine. Our identified CTL epitopes have the potential to inhibit SARS-CoV-2 replication.

An overview of gastrointestinal diseases in patients with COVID-19: A narrative review.

Coronavirus disease-2019 (COVID-19), caused by severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2), has emerged as a global health concern. This study aimed to review the epidemiology and pathophysiology of COVID-19 and provide evidence for the implementation of control measures. We utilized several online databases, including MEDLINE (National Library of Medicine, Bethesda, Maryland, USA), PubMed, EMBASE, Web of Science, and Google Scholar, to collect relevant published papers using a combination of the following keywords: "COVID-19," "SARS-CoV-2," "novel coronavirus," "epidemiology," and "pathophysiology." The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were used in this study. Globally, approximately 3-46% of patients with SARS-CoV-2 infection experience gastrointestinal symptoms. The clinical spectrum of COVID-19 is wide, ranging from mild to severe, and even fatal. COVID-19 was initially reported as a respiratory tract disease; however, gastrointestinal symptoms have only recently been reported. COVID-19 Patients with gastrointestinal symptoms may have more severe clinical manifestations and poor prognosis. This study highlights the need to better understand the mechanisms involved in the development of gastrointestinal symptoms in patients with COVID-19 to prevent the further spread of this pathogen.

Emerging Infectious Diseases and One Health: Implication for Public Health.

Emerging infectious diseases (EIDs) are defined as diseases that are newly identified, newly introduced, or newly evolved; or diseases that have recently and rapidly changed in incidence or expanded geographic, host, or vector range agents; or previous infections that acquire new virulence factors; or infections that spread to unaffected regions [...].