Computational investigation of drug bank compounds against 3C-like protease (3CLpro) of SARS-CoV-2 using deep learning and molecular dynamics simulation

Blocking the main replicating enzyme, 3 Chymotrypsin-like protease (3CL^pro) is the most promising drug development strategy against the SARS-CoV-2 virus, responsible for the current COVID-19 pandemic. In the present work, 9101 drugs obtained from the drug bank database were screened against SARS-CoV-2 3CL^pro prosing deep learning, molecular docking, and molecular dynamics simulation techniques. In the initial stage, 500 drug-screened by deep learning regression model and subjected to molecular docking that resulted in 10 screened compounds with strong binding affinity. Further, five compounds were checked for their binding potential by analyzing molecular dynamics simulation for 100 ns at 300 K. In the final stage, two compounds {4-[(2s,4e)-2-(1,3-Benzothiazol-2-Yl)-2-(1h-1,2,3-Benzotriazol-1-Yl)-5-Phenylpent-4-Enyl]Phenyl}(Difluoro)Methylphosphonic Acid and 1-(3-(2,4-dimethylthiazol-5-yl)-4-oxo-2,4-dihydroindeno[1,2-c]pyrazol-5-yl)-3-(4-methylpiperazin-1-yl)urea were screened as potential hits by analyzing several parameters like RMSD, Rg, RMSF, MMPBSA, and SASA. Thus, our study suggests two potential drugs that can be tested in the experimental conditions to evaluate the efficacy against SARS-CoV-2. Further, such drugs could be modified to develop more potent drugs against COVID-19.

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Seed free high yield gold nanorods synthesis from single precursor gold(I) dithiophosphate complex

In this work, we demonstrate a simple, one pot and seed free synthetic route for the formation of gold nanorods (Au NRs) via thermal decomposition of gold(I) dithiophosphate {[Au₂{S₂P(OⁱPr)₂}₂]_n,} 1 complex as a molecular precursor in presence of 4′‐amino‐biphenyl‐4‐carboxylic molecule. Here [Au₂{S₂P(OⁱPr)₂}₂]_n, complex functioned as gold (Au) source and 4′‐amino‐biphenyl‐4‐carboxylic molecule stabilized gold (Au) nanorods (NRs) through the unidirectional coating of Au surface during its growth in the reaction medium.     

Anti-inflammatory activity of Pistacia lentiscus essential oil: involvement of IL-6 and TNF-alpha

The topical anti-inflammatory activity of essential oil of Pistacia lentiscus L. was studied using carrageenan induced rat paw edema and cotton pellet induced granuloma. The effect on serum tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6) in rats inserted with cotton pellet was also investigated. On topical application, the oil exhibited a significant decrease in paw edema. The oil also inhibited cotton pellet-induced granuloma, and reduced serum TNF-alpha and IL-6. It can be concluded that the essential oil of Pistacia lentiscus reduces leukocyte migration to the damaged tissue and exhibits anti-inflammatory activity.     

Electroanalytical Method for Quantification of Hepatocellular Carcinoma Cells as Charge Transport Barriers in Culture Media

Here we report a strategy in which electroanalytical method was used to quantify human hepatic carcinoma cell (HepG2) density in culture media and their interaction with biomolecules. The cyclic voltammogram response of vitamin and amino acids redox mediators containing culture media had shown distinct oxidation peak at ?0.63 V along with a low intensity peak at +0.67 V. Both oxidation and reduction peak current of culture media were gradually decreased with an increase in cell number indicating their role as charge transport barrier at electrode surface. The difference between cathodic and anodic peak potential was also decreased with the addition of cells. The oxidation peak disappeared in CV response, with the addition of optimum cell number in culture media, indicating the adsorption of redox mediators at cell surface. CV response of fetal bovine serum (FBS) containing cell suspension showed presence of reduction and oxidation peaks of culture media in CV. This indicates stronger possibility of binding of serum proteins with cells and release of redox mediators in culture media. The chemical interactions of cells with FBS was further confirmed by the FTIR and UV‐Vis spectroscopy. The viability, adhesion and proliferation responses of the cells were found to be normal. The reported electroanalytical method may be applied in the future for rapid quantification of cell density and confirmation of interactions among cells and biomolecules.     

Development of a method for the estimation of low amount of plutonium in 200 L waste drums in presence of high amount of β γ activity due to 137Cs and 60Co

The waste drum monitoring system based on HPGe detector was used to study its performance for the estimation of low amounts of plutonium in presence of high activity of ¹³⁷Cs and ⁶⁰Co. The counting was carried out by keeping amount of plutonium constant at 100 mg level and varying the count rate for the γ rays of ¹³⁷Cs and ⁶⁰Co. Present study has shown that the estimation of low amount of ²³⁹Pu in a waste drum can be carried out using 129 keV γ ray in the presence of ¹³⁷Cs up to an activity level of 16 mCi and in the presence of ⁶⁰Co up to an activity level of 8 mCi.     

Entangling capabilities of symmetric two-qubit gates

Our work addresses the problem ofgenerating maximally entangled two spin-1/2 (qubit) symmetric states using NMR, NQR, Lipkin–Meshkov–Glick Hamiltonians. Time evolution of such Hamiltonians provides various logic gates which can be used for quantum processing tasks. Pairs of spin-1/2s have modelled a wide range of problems in physics. Here, we are interested in two spin-1/2 symmetric states which belong to a subspace spanned by the angular momentum basis {|j = 1, μ〉; μ = + 1, 0, ?1}. Our technique relies on the decomposition of a Hamiltonian in terms of SU(3) basis matrices. In this context, we define a set of linearly independent, traceless, Hermitian operators which provides an alternate set of SU(n) generators. These matrices are constructed out of angular momentum operators J _x , J _y , J _z . We construct and study the properties of perfect entanglers acting on a symmetric subspace, i.e., spin-1 operators that can generate maximally entangled states from some suitably chosen initial separable states in terms of their entangling power.     

<Emphasis Type="Italic">SU</Emphasis>(2) invariants of symmetric qubit states

We express the density matrix for the N-qubit symmetric state or spin-j state (j = N/2) in terms of the well-known Fano statistical tensor parameters. Employing the multi-axial representation, where the spin-j density matrix is shown to be characterized by j(2j + 1) axes and 2j real scalars, we enumerate the number of invariants constructed out of these axes and scalars. We calculate these invariants explicitly in the particular case of the pure and mixed spin-1 state.