Dental workers in front-line of COVID-19: an in silico evaluation targeting their prevention.

OBJECTIVE: SARS-CoV-2 has high human-human transmission rate. The aerosols and saliva droplets are the main contamination source. Thus, it is crucial to point out that dental practitioners become a high-risk group of contagion by SARS-CoV-2. Based on this, protocols have been recommended to avoid cross-contamination during dental care; however, appropriate evidence has not yet been established. Our study sought to make a screening, by in silico analysis, of the potential of mouth rinses used in dental practices to prevent the dental workers' contamination by SARS-CoV-2. METHODOLOGY: Multiple sequence comparisons and construction of the phylogenetic tree were conducted using the FASTA code. Therefore, molecular docking investigation between SARS-CoV-2 proteins (Main Protease, Spike Glycoprotein, Non-structure Protein, and Papain-like Protease) and molecules used in dental practices (chlorhexidine digluconate, hydrogen peroxide, cetylpyridinium chloride, povidone-iodine, gallic acid, ß-cyclodextrin, catechin, and quercetin) was performed using AutoDock Vina. Moreover, 2D interactions of the complex protein-ligand structure were analyzed by Ligplot+. RESULTS: The obtained results showed a remarkable affinity between SARS-CoV-2 proteins and all tested compounds. The chlorhexidine digluconate, catechin, and quercetin presented a higher affinity with SARS-CoV-2. CONCLUSIONS: The overall results allowed us to suggest that chlorhexidine is the most suitable active compound in reducing the SARS-CoV-2 salivary load due to its better binding energy. However, in vivo studies should be conducted to confirm their clinical use.

Dental workers in front-line of COVID-19: an in silico evaluation targeting their prevention

Abstract SARS-CoV-2 has high human-human transmission rate. The aerosols and saliva droplets are the main contamination source. Thus, it is crucial to point out that dental practitioners become a high-risk group of contagion by SARS-CoV-2. Based on this, protocols have been recommended to avoid cross-contamination during dental care; however, appropriate evidence has not yet been established. Objective Our study sought to make a screening, by in silico analysis, of the potential of mouth rinses used in dental practices to prevent the dental workers' contamination by SARS-CoV-2. Methodology Multiple sequence comparisons and construction of the phylogenetic tree were conducted using the FASTA code. Therefore, molecular docking investigation between SARS-CoV-2 proteins (Main Protease, Spike Glycoprotein, Non-structure Protein, and Papain-like Protease) and molecules used in dental practices (chlorhexidine digluconate, hydrogen peroxide, cetylpyridinium chloride, povidone-iodine, gallic acid, β-cyclodextrin, catechin, and quercetin) was performed using AutoDock Vina. Moreover, 2D interactions of the complex protein-ligand structure were analyzed by Ligplot+. Results The obtained results showed a remarkable affinity between SARS-CoV-2 proteins and all tested compounds. The chlorhexidine digluconate, catechin, and quercetin presented a higher affinity with SARS-CoV-2. Conclusions The overall results allowed us to suggest that chlorhexidine is the most suitable active compound in reducing the SARS-CoV-2 salivary load due to its better binding energy. However, in vivo studies should be conducted to confirm their clinical use.

PVA-Glutaraldehyde as support for lectin immobilization and affinity chromatography / PVA-Glutaraldeído como suporte para imobilização de lectina e cromatografia de afinidade

Immobilized lectins are a powerful biotechnological tool for separation and isolation of glycoconjugates. In the present study, polyvinyl alcohol (PVA) and glutaraldehyde (GA) were used as a support for Concanavalin A (Con A) covalent immobilization and for entrapment of Parkia pendula seed gum (PpeG). Con A immobilization yielded approximately 30% and 0.6 M glucose solution was the minimum concentration able to elute fetuin from column. PVA-GA-PpeG column was efficiently recognized by pure P. pendula lectin (PpeL) . These findings indicate that PVA-GA interpenetrated network showed to be an efficient support for lectin covalent immobilization and as affinity chromatography matrix after trapping of PpeG.

Lectinas imobilizadas são uma poderosa ferramenta biotecnológica para a separação e isolamento de glicoconjugados. No presente trabalho álcool polivinílico (PVA) e glutaraldeído (GA) foram utilizados como um suporte para a imobilização covalente da Concanavalina A (Con A) e para aprisionamento da goma de semente de Parkia pendula (PpeG). A eficiência da imobilização da Con A foi aproximadamente 30 % e a concentração mínima de glucose capaz de eluir a fetuína da coluna foi 0,6 M. Coluna de PVA - GA - PpeG foi eficientemente reconhecida pela lectina de P. pendula (PpeL) pura. Estes resultados indicam que a rede interpenetrada de PVA-GA mostrou-se um suporte eficiente para a imobilização covalente de lectina e como matriz de cromatografia de afinidade após aprisionamento de PpeG.