Synergistic antiviral potential of N-(2-hydroxy)propyl-3-trimethylammoniumchitosan-functionalized silver nanoparticles with oseltamivir against influenza A viruses.

This study introduced a novel antiviral approach by combining three substances with different antiviral mechanisms: N-(2-hydroxy)propyl-3-trimethylammoniumchitosan (HTC), silver nanoparticles (AgNPs), and oseltamivir. First, positively surface-charged AgNPs were prepared using an environmentally friendly method. The surfaces of these AgNPs were capped with cationic quaternary chitosan HTC.

Polyelectrolyte-coated liposomes microfluidically assembled in one-step for enhancing cell endocytosis and in-vivo immune responses.

To enhance the cellular uptake of liposomes, we prepared conventional liposomes with targeting molecules and surface-charged liposomes and evaluated their potential as nano-carriers and vaccine adjuvants by comparing their endocytosis efficiencies using immune cells. Surface-charged liposomes were synthesized via a one-step microfluidic method, which provided a novel, simple, fast, and highly reproducible method for preparing liposomes. Flow cytometry revealed that cationic polyelectrolyte-coated liposomes exhibited higher endocytosis efficiencies (of up to a factor of 100) in A774A.

Functional and structural investigation of a broadly neutralizing SARS-CoV-2 antibody.

Since its emergence, SARS-CoV-2 has been continuously evolving, hampering the effectiveness of current vaccines against COVID-19. mAbs can be used to treat patients at risk of severe COVID-19. Thus, the development of broadly protective mAbs and an understanding of the underlying protective mechanisms are of great importance.

BPR3P0128, a non-nucleoside RNA-dependent RNA polymerase inhibitor, inhibits SARS-CoV-2 variants of concern and exerts synergistic antiviral activity in combination with remdesivir.

Viral RNA-dependent RNA polymerase (RdRp), a highly conserved molecule in RNA viruses, has recently emerged as a promising drug target for broad-acting inhibitors. Through a Vero E6-based anti-cytopathic effect assay, we found that BPR3P0128, which incorporates a quinoline core similar to hydroxychloroquine, outperformed the adenosine analog remdesivir in inhibiting RdRp activity (EC = 0.66 µM and 3 µM, respectively).

Simultaneous detection of SARS-CoV-2 S1 protein by using flexible electrochemical and Raman enhancing biochip.

Flexible laser-scribed graphene (LSG) substrates with gold nanoislands have been developed as biochips for in situ electrochemical (EC) and surface-enhanced Raman scattering (SERS) biodetection (biomolecules and viral proteins). A flexible biochip was fabricated using CO laser engraving polyimide (PI) films to form a 3D porous graphene-like nanostructure. Gold nanoislands were deposited on the LSG substrates to enhance the intensity of the Raman signals.

Development of an EBOV MiniG plus system as an advanced tool for anti-Ebola virus drug screening.

The incidence of zoonotic diseases, such as coronavirus disease 2019 and Ebola virus disease, is increasing worldwide. However, drug and vaccine development for zoonotic diseases has been hampered because the experiments involving live viruses are limited to high-containment laboratories. The Ebola virus minigenome system enables researchers to study the Ebola virus under BSL-2 conditions.

Development of AAV-delivered broadly neutralizing anti-human ACE2 antibodies against SARS-CoV-2 variants.

The ongoing evolution of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), resulting in the emergence of new variants that are resistant to existing vaccines and therapeutic antibodies, has raised the need for novel strategies to combat the persistent global COVID-19 epidemic. In this study, a monoclonal anti-human angiotensin-converting enzyme 2 (hACE2) antibody, ch2H2, was isolated and humanized to block the viral receptor-binding domain (RBD) binding to hACE2, the major entry receptor of SARS-CoV-2. This antibody targets the RBD-binding site on the N terminus of hACE2 and has a high binding affinity to outcompete the RBD.

Immunoglobulin Y Specific for SARS-CoV-2 Spike Protein Subunits Effectively Neutralizes SARS-CoV-2 Infectivity and Ameliorates Disease Manifestations In Vivo.

(Background) The coronavirus disease 2019 (COVID-19) that is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) carries high infectivity and mortality. Efficient intervention strategies are urgently needed. Avian immunoglobulin Y (IgY) showed efficacy against viral infection whereas the in vivo efficacy remains unclear.

Employing functionalized graphene quantum dots to combat coronavirus and enterovirus.

The ongoing COVID-19 (i.e., coronavirus) pandemic continues to adversely affect the human life, economy, and the world's ecosystem.

Replica of Bionic Nepenthes Peristome-like and Anti-Fouling Structures for Self-Driving Water and Raman-Enhancing Detection.

The flexible, anti-fouling, and bionic surface-enhanced Raman scattering (SERS) biochip, which has a Nepenthes peristome-like structure, was fabricated by photolithography, replicated technology, and thermal evaporation. The pattern of the bionic Nepenthes peristome-like structure was fabricated by two layers of photolithography with SU-8 photoresist. The bionic structure was then replicated by polydimethylsiloxane (PDMS) and grafting the zwitterion polymers (2-methacryloyloxyethyl phosphorylcholine, MPC) by atmospheric plasma polymerization (PDMS-PMPC).

Orally delivered perilla (Perilla frutescens) leaf extract effectively inhibits SARS-CoV-2 infection in a Syrian hamster model.

On analyzing the results of cell-based assays, we have previously shown that perilla (Perilla frutescens) leaf extract (PLE), a food supplement and orally deliverable traditional Chinese medicine approved by the Taiwan Food and Drug Administration, effectively inhibits SARS-CoV-2 by directly targeting virions. PLE was also found to modulate virus-induced cytokine expression levels. In this study, we explored the anti-SARS-CoV-2 activity of PLE in a hamster model by examining viral loads and virus-induced immunopathology in lung tissues.

Alginate-Capped Silver Nanoparticles as a Potent Anti-mycobacterial Agent Against .

Tuberculosis (TB) is a leading cause of death from a single infectious agent, (). Although progress has been made in TB control, still about 10 million people worldwide develop TB annually and 1.5 million die of the disease.

Nanoparticular CpG-adjuvanted SARS-CoV-2 S1 protein elicits broadly neutralizing and Th1-biased immunoreactivity in mice.

The spike (S) protein is a leading vaccine candidate against SARS-CoV-2 infection. The S1 domain of S protein, which contains a critical receptor-binding domain (RBD) antigen, potentially induces protective immunoreactivities against SARS-CoV-2. In this study, we presented preclinical evaluations of a novel insect cell-derived SARS-CoV-2 recombinant S1 (rS1) protein as a potent COVID-19 vaccine candidate.

Ser253Leu substitution in PmrB contributes to colistin resistance in clinical .

Infections caused by extensively drug-resistant (XDR) have become a challenging problem. The frequent use of colistin as the last resort drug for XDR bacteria has led to the emergence of colistin-resistant (ColRAN) in hospitals. The mechanism of colistin resistance in remains unclear.

Perilla (Perilla frutescens) leaf extract inhibits SARS-CoV-2 via direct virus inactivation.

Background: While severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection presents with mild or no symptoms in most cases, a significant number of patients become critically ill. Remdesivir has been approved for the treatment of coronavirus disease 2019 (COVID-19) in several countries, but its use as monotherapy has not substantially lowered mortality rates. Because agents from traditional Chinese medicine (TCM) have been successfully utilized to treat pandemic and endemic diseases, we designed the current study to identify novel anti-SARS-CoV-2 agents from TCM.

E3 ubiquitin ligase Grail promotes hepatic steatosis through Sirt1 inhibition.

In obese adults, nonalcoholic fatty liver disease (NAFLD) is accompanied by multiple metabolic dysfunctions. Although upregulated hepatic fatty acid synthesis has been identified as a crucial mediator of NAFLD development, the underlying mechanisms are yet to be elucidated. In this study, we reported upregulated expression of gene related to anergy in lymphocytes (GRAIL) in the livers of humans and mice with hepatic steatosis.

Nanoparticles assembled from fucoidan and trimethylchitosan as anthrax vaccine adjuvant: In vitro and in vivo efficacy in comparison to CpG.

Fucoidan/trimethylchitosan nanoparticles (FUC-TMC-NPs) have the potential to improve the immunostimulating efficiency of anthrax vaccine adsorbed (AVA). FUC-TMC-NPs with positive (+) or negative (-) surface charges were prepared via polyelectrolyte complexation, both charged NP types permitted high viability and presented no cytotoxicity on L929, A549 and JAWS II dendritic cells. Flow cytometry measurements indicated lower (+)-FUC-TMC-NPs internalization levels than (-)-FUC-TMC-NPs, yet produced high levels of pro-inflammatory cytokines IFN-γ, IL12p40, and IL-4.

A fucoidan-quaternary chitosan nanoparticle adjuvant for anthrax vaccine as an alternative to CpG oligodeoxynucleotides.

We examined the efficacy of fucoidan-N-(2-hydroxy-3-trimethylammonium)propylchitosan nanoparticles (FUC-HTCC NPs) as adjuvants for anthrax vaccine adsorbed (AVA). Positively and negatively surface-charged FUC-HTCC NPs were prepared via polyelectrolyte complexation by varying the mass ratio of FUC and HTCC. When cultured with L929 cells or JAWS II dendritic cells, both charged NPs showed high cell viability and low cytotoxicity, observed via MTT assay and lactate dehydrogenase release assay, respectively.

Fungicidal and anti-biofilm activities of trimethylchitosan-stabilized silver nanoparticles against Candida species in zebrafish embryos.

Herein, positively surface-charged silver nanoparticles (AgNPs) capped with trimethylchitosan nitrate (TMCN) were synthesized using an environmentally friendly method. Nano-sized TMCN-AgNPs (~80 nm) with high zeta potential (>30 mV) provide sufficient static repulsion to stabilize colloid AgNPs in aqueous solutions without aggregation for >3 months. In in vitro cell cycle assays, TMCN-AgNPs showed low cytotoxicity towards L929 cells.

Grail attenuates influenza A virus infection and pathogenesis by inhibiting viral nucleoprotein.

Grail is a well-characterized mediator of metabolic disease, tumour progression, and immune response. However, its role in influenza A virus (IAV) infection remains poorly understood. In this study, we demonstrated that Grail knockdown potentiates IAV infection, whereas Grail overexpression blocks IAV replication.

Positively charged gold nanoparticles capped with folate quaternary chitosan: Synthesis, cytotoxicity, and uptake by cancer cells.

In this study, we synthesized various quaternary chitosan derivatives and used them to stabilize gold nanoparticles (AuNPs). These chitosan derivatives comprised N-(2-hydroxy)propyl-3-trimethylammonium chitosan chloride (HTCC), folate-HTCC, galactosyl-HTCC, and their fluorescein isothiocyanate-conjugated derivatives. Various positively surface-charged AuNPs were prepared under alkaline conditions using glucose as a reducing agent in the presence of the HTCC derivatives (HTCCs).

Chondroitin sulfate-stabilized silver nanoparticles: Improved synthesis and their catalytic, antimicrobial, and biocompatible activities.

Herein, we describe an improved procedure for the green synthesis of chondroitin sulfate stabilized silver nanoparticles (ChS-AgNPs). Glucose was used as a reducing agent under alkaline conditions to obtain a small particle size (<10 nm), and the reduction was complete within one hour at room temperature. The concentration of NaOH affected the reaction rate, formation yield, and particle size of ChS-AgNPs.

Positively and negatively surface-charged chondroitin sulfate-trimethylchitosan nanoparticles as protein carriers.

Positively and negatively surface-charged nanoparticles (NPs) were prepared with chondroitin sulfate (ChS) and trimethylchitosan (TMC). NP size, surface charge, formation yield, and water content were investigated as a function of weight ratio and concentration. Size and zeta potential were controlled by varying the ChS/TMC mass ratio.

Novel protein-loaded chondroitin sulfate-N-[(2-hydroxy-3-trimethylammonium)propyl]chitosan nanoparticles with reverse zeta potential: preparation, characterization, and ex vivo assessment.

A facile polyelectrolyte complexation method for the preparation of both positively and negatively surface charged nanoparticles composed of chondroitin sulfate (ChS) and N-[(2-hydroxy-3-trimethylammonium)propyl]chitosan (HTCC) is reported. Production of ChS-HTCC nanoparticles with reverse zeta potential was easily controlled by varying the ChS/HTCC mass ratio. The encapsulation efficiency increased with the increase in initial FITC-BSA concentration in positively charged NPs and reached 75%.