Structural and theoretical investigations, Hirshfeld surface analysis and anti-SARS CoV-2 of nickel (II) coordination complex

A nickel(II) Schiff base complex, [Ni(L)(DMF)](1), was synthesized by treating NiCl2.6H2O with an ONS-donor Schiff base ligand(H2L) derived from the condensation 3,5-Dichlorosalicylaldehyde and 4,4-Dimethyl-3-thiosemicarbazide in DMF. The geometry around the center metal ion in [Ni(L)(DMF)](1) was square planar as revealed by the data collection from diffraction studies. DFT calculations were performed on the complex to get a structure-property relationship. Hirshfeld surface analysis was also carried out in the crystal structure of nickel (II) Schiff base complex. Additionally, inspiring from recent developments to find a potential inhibitor for SARS-CoV-2 virus, we have also performed molecular docking study of [Ni(L)(DMF)](1) to see if our novel complex show affinity for main protease (Mpro) of SARS-CoV-2 Mpro (PDB ID: 6LZE). Interestingly, the results are found quite encouraging where the binding affinity and inhibition constant was found to be −6.6 kcal/mol and 2.358 µM, respectively, for the best docked confirmation of complex [Ni(L)(DMF)](1) with Mpro protein. This binding affinity is reasonably well as compared to recently known antiviral drugs. For instance, the binding affinity of complex [Ni(L)(DMF)](1) is found to be better than that of recently docking results of anti-SARS-CoV-2 drugs like chloroquine (-6.293 kcal/mol), hydroxychloroquine (-5.573 kcal/mol) and remdesivir (-6.352 kcal/mol) when targeted to the active-site of SARS-CoV-2 Mpro. Besides this, molecular docking against G25K GTP-nucleotide binding protein (PDB ID: 1A4R) was also studied. We believe that current results can intrigue not only for the biomedical community but also for the materials chemists who are engaged to explore the application coordination complexes. Communicated by Ramaswamy H. Sarma. © 2021 Informa UK Limited, trading as Taylor & Francis Group.

Design and molecular docking studies of {N1-[2-(amino)ethyl]ethane-1,2-diamine}-[tris(oxido)]-molybdenum(VI) complex as a potential antivirus drug: from synthesis to structure

The aim of this study was to synthesize and examine the molecular docking of a Mo(VI) complex [Mo(dien)O3] (1), {N1-[2-(amino)ethyl]ethane-1,2-diamine}-[tris(oxido)]-molybdenum(VI) as a potential antivirus drug against the SARS-CoV-2, HIV and polio viruses. [Mo(dien)O3] (1) was fully characterized, including single crystal x-ray crystallography. The complex was crystallized in the orthorhombic crystal system with Pbcm space group and has distorted octahedral coordination geometry. DFT calculations have been explored for structure-property relationships. The Hirshfeld surface analysis and 2D fingerprint plots were also performed to investigate intermolecular interactions in the crystal structure. Antibacterial activities of 1 were also studied. In order to have insight into the potential application of 1 as an effective antivirus agent, we have examined the molecular docking of 1 with SARS-CoV-2 Mpro (PDB ID: 7N0I), HIV virus (PDB ID: 6MCF), Polio virus (PDB ID: 1HXS), and DNA duplex dodecamer (PDB ID: 1BNA). The molecular docking results reveal that 1 with Mpro of SARS-CoV-2, HIV-1 RNA and Polio virus resulted in binding energies (ΔG) of −9.9 kcal/mol, −8.8 kcal/mol and −8.4 kcal/mol with good inhibition constant (Ki) of 6.539 µM, 5.113 µM and 4.237 µM, respectively. Overall, in silico molecular docking predicts potential antivirus effects of 1 against the virus of SARS CoV-2, HIV, and Polio. © 2023 Informa UK Limited, trading as Taylor & Francis Group.

Role of Chest Radiography as the Imaging Tool in COVID Pandemic Era

Background: The present radiological COVID literature is mainly confined to the CT findings. Using High Resolution Computed tomography (HRCT) as a regular 1st line investigation put a large burden on radiology department and constitute a huge challenge for the infection control in CT suite. Materials and Methods: A prospective study of 700 consecutive COVID positive cases who underwent Chest Xray (CXR) and HRCT thorax were included in the study. Many of these CXR were repeated and followed up over a duration of time to see the progression of disease. Results: 392/700 (56%) were found to be negative for radiological thoracic involvement. 147/700 (21%) COVID positive patients showed lung consolidations, 115/700 (16.5%) presented with GGO, 40/700 (5.7%) with nodules and 42/700 (6%) with reticular–nodular opacities. 150/700 patients (21.4 %) had mild findings with total RALE severity score of 1-2. More extensive involvement was seen in 104/700 (14.8 %) and 43/700 (6.2%) patients, who had severity scores of 3-4 and 5-6 respectively. 11/700 patients had a severity score of >6 on their baseline CXR. Those with severity score of 5 or more than 5 (54/700, 7.7%) required aggressive treatment with mean duration of stay of 14 days, many of them died also (23/54, 42.5%). Conclusion: In cases of high clinical suspicion for COVID-19, a positive CXR may obviate the need for CT. Additionally, CXR utilization for early disease detection and followup may also play a vital role in areas around the world with limited access to CT and RT-PCR test.

A Review Study to Investigate the Tracking of Biomedical Waste during Covid-19 Pandemic in India

The aim of this review article is planning to collect, transport, processing and dispose of hazardous and non-hazardous biomedical waste, with a special concern on the biomedical waste tracking system in India. This review article sheds insight on some of the tracking systems of COVID-19 waste over the barcode, IoT, and GPS-based trash monitoring, related to COVID-19 waste management. Better waste management may reduce the amount of time that garbage is exposed to the environment and the risk of transportation. COVID-19 waste treatment facility might assist to reduce the risk of coronavirus transmission, as well as the hazardous component risk respectively. © 2021 Taylor & Francis Group, LLC.

In silico identification of potential inhibitors of key SARS-CoV-2 3CL hydrolase (Mpro) via molecular docking, MMGBSA predictive binding energy calculations, and molecular dynamics simulation.

The incidence of 2019 novel corona virus (SARS-CoV-2) has created a medical emergency throughout the world. Various efforts have been made to develop the vaccine or effective treatments against the disease. The discovery of crystal structure of SARS-CoV-2 main protease has made the in silico identification of its inhibitors possible. Based on its critical role in viral replication, the viral protease can prove to be a promising "target" for antiviral drug therapy. We have systematically screened an in-house library of 15,754 natural and synthetic compounds, established at International Center for Chemical and Biological Sciences, University of Karachi. The in silico search for potential viral protease inhibitors resulted in nine top ranked ligands (compounds 1-9) against SARS-CoV-2 main protease (PDB ID: 6LU7) based on docking scores, and predictive binding energies. The in silico studies were updated via carrying out the docking, and predictive binding energy estimation, with a recently reported crystal structure of main protease (PDB ID: 6Y2F) at a better resolution i.e., 1.95 Å. Compound 2 (molecular bank code AAA396) was found to have highest negative binding energy of -71.63 kcal/mol for 6LU7. While compound 3 (molecular bank code AAD146) exhibited highest negative binding energy of -81.92 kcal/mol for 6Y2F. The stability of the compounds- in complex with viral protease was analyzed by Molecular Dynamics simulation studies, and was found to be stable over the course of 20 ns simulation time. Compound 2, and 3 were predicted to be the significant inhibitors of SARS-CoV-2 3CL hydrolase (Mpro) among the nine short listed compounds.