A review on the cleavage priming of the spike protein on coronavirus by angiotensin-converting enzyme-2 and furin.

The widespread antigenic changes lead to the emergence of a new type of coronavirus (CoV) called as severe acute respiratory syndrome (SARS)-CoV-2 that is immunologically different from the previous circulating species. Angiotensin-converting enzyme-2 (ACE-2) is one of the most important receptors on the cell membrane of the host cells (HCs) which its interaction with spike protein (SP) with a furin-cleavage site results in the SARS-CoV-2 invasion. Hence, in this review, we presented an overview on the interaction of ACE-2 and furin with SP.

Combined chemo-magnetic field-photothermal breast cancer therapy based on porous magnetite nanospheres.

The efficacy of different modalities of treating breast cancer is inhibited by several limitations such as off-targeted drug distribution, rapid drug clearance, and drug resistance. To overcome these limitations, we developed Lf-Doxo-PMNSs for combined chemo-MF-PTT. The PMNSs were synthesized by hydrothermal method and their physicochemical properties were examined by FE-SEM, TEM, DLS, TGA, XRD investigations.

Plasmonic and chiroplasmonic nanobiosensors based on gold nanoparticles.

Development of optical nanobiosensors has emerged as one of the most important bioresearch areas of interest over the past decades especially in the modern innovations in the design and utilization of sensing platforms. The application of nanobiosensors has been accelerated with the introduction of plasmonic NPs, which overcome the most of the limitations in the case of conventional optical nanobiosensors. Since the plasmonic AuNPs-based nanobiosensors provide high potential achievements to develop promising platforms in fully integrated multiplex assays, some well-developed investigations are clearly required to improve the current technologies and integration of multiple signal inputs.

Gold nanozyme: Biosensing and therapeutic activities.

The utilization of AuNPs in therapeutic applications has been accelerated by discovering their catalytic activity consistent with the activity of natural enzymes. However, to reduce unwanted activities, it is imperative to fully understand their catalytic mechanisms to increase efficiency and safety. Therefore, along with other reports, we aimed to classify the enzymatic activity of Au nanozymes based on recent advance in their applications in biosensing and therapeutic activities.

Enzyme immobilization onto the nanomaterials: Application in enzyme stability and prodrug-activated cancer therapy.

Nanoparticles (NPs) have been widely used for immobilization of wide ranges of enzymes. However, the stabilization of enzymes on NPs is a major challenge, crucial for regulating enzymatic activity and their medical applications. To overcome these challenges, it is necessary to explore how enzymes attach to nanomaterials and their properties are affected by such interactions.

Vitamin K1 As A Potential Molecule For Reducing Single-Walled Carbon Nanotubes-Stimulated α-Synuclein Structural Changes And Cytotoxicity.

Aims: Different kinds of vitamins can be used as promising candidates to mitigate the structural changes of proteins and associated cytotoxicity stimulated by NPs. Therefore, the structural changes of α-syn molecules and their associated cytotoxicity in the presence of SWCNTs either alone or co-incubated with vitamin K1 were studied by spectroscopic, bioinformatical, and cellular assays.

Methods: Intrinsic and ThT fluorescence, CD, and Congo red absorption spectroscopic approaches as well as TEM investigation, molecular docking, and molecular dynamics were used to explore the protective effect of vitamin K1 on the structural changes of α-syn induced by SWCNTs.

Silymarin-albumin nanoplex: Preparation and its potential application as an antioxidant in nervous system in vitro and in vivo.

In this study, we formulated silymarin-HSA nanoplex and assayed its ability to reduce LPS-induced toxicity in vitro and in vivo. Silymarin molecules were encapsulated into HSA nanoplex and the loading efficiency and characterization of fabricated nanoplex were performed by using HPLC, TEM, SEM, DLS, FTIR analysis, and theoretical studies. Afterwards, their protective effect against LPS (20 µg/ml) -induced toxicity in SH-SY5Y cells was investigated by MTT, ROS, and apoptosis assays.

Cerium oxide NPs mitigate the amyloid formation of α-synuclein and associated cytotoxicity.

Aim: Among therapeutic proposals for amyloid-associated disorders, special attention has been given to the exploitation of nanoparticles (NPs) as promising agents against aggregation.

Methods: In this paper, the inhibitory effect of cerium oxide (CeO) NPs against α-synuclein (α-syn) amyloid formation was explored by different methods such as Thioflavin T (ThT) and 8-anilinonaphthalene-1-sulfonic acid (ANS) fluorescence spectroscopy, Congo red adsorption assay, circular dichroism (CD) spectroscopy, transmission electron microscopy (TEM), and bioinformatical approaches. Also, the cytotoxicity of α-syn amyloid either alone or with CeO NPs against neuron-like cells (SH-SY5Y) was examined using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), flow cytometry, and quantitative real-time polymerase chain reaction (Bax and Bcl-2 gene expression) assays.

Gold nanomaterials as key suppliers in biological and chemical sensing, catalysis, and medicine.

Background: Gold nanoparticles (AuNPs) with unique physicochemical properties have received a great deal of interest in the field of biological, chemical and biomedical implementations. Despite the widespread use of AuNPs in chemical and biological sensing, catalysis, imaging and diagnosis, and more recently in therapy, no comprehensive summary has been provided to explain how AuNPs could aid in developing improved sensing and catalysts systems as well as medical settings.

Scope Of Review: The chemistry of Au-based nanosystems was followed by reviewing different applications of Au nanomaterials in biological and chemical sensing, catalysis, imaging and diagnosis by a number of approaches, and finally synergistic combination therapy of different cancers.

The effects of nickel oxide nanoparticles on structural changes, heme degradation, aggregation of hemoglobin and expression of apoptotic genes in lymphocytes.

Nickel oxide nanoparticles (NiO NPs) have received great interests in medical and biotechnological applications. However, their adverse impacts against biological systems have not been well-explored. Herein, the influence of NiO NPs on structural changes, heme degradation and aggregation of hemoglobin (Hb) was evaluated by UV-visible (Vis) spectroscopy, circular dichroism (CD) spectroscopy, fluorescence spectroscopy, transmission electron microscopy (TEM), and molecular modeling investigations.

α-synuclein interaction with zero-valent iron nanoparticles accelerates structural rearrangement into amyloid-susceptible structure with increased cytotoxic tendency.

Aim: It has been indicated that NPs may change the amyloidogenic steps of proteins and relevant cytotoxicity. Therefore, this report assigned to explore the impact of ZVFe NPs on the amyloidogenicity and cytotoxicity of α-synuclein as one of the many known amyloid proteins.

Methods: The characterization of α-synuclein at amyloidogenic condition either alone or with ZVFe NPs was carried out by fluorescence, CD, UV-visible spectroscopic methods, TEM study, docking, and molecular modeling.

The interaction of silica nanoparticles with catalase and human mesenchymal stem cells: biophysical, theoretical and cellular studies.

Aim: Nanoparticles (NPs) have been receiving potential interests in protein delivery and cell therapy. As a matter of fact, NPs may be used as great candidates in promoting cell therapy by catalase (CAT) delivery into high oxidative stress tissues. However, for using NPs like SiO as carriers, the interaction of NPs with proteins and mesenchymal stem cells (MSCs) should be explored in advance.

The effect of aluminum oxide on red blood cell integrity and hemoglobin structure at nanoscale.

Herein, we explored the interaction of AlO NPs with RBCs and Hb to determine the effect of AlO NPs on hemolytic activity and Hb denaturation. The percentage of hemolysis of extracts and direct contact assays triggered by AlO NPs was calculated by determining supernatant Hb concentration at 540 nm. Far-UV CD and Trp/ANS/acrylamide fluorescence spectroscopic methods were used to determine the structural changes of Hb upon interaction with AlO NPs.

Strategies of enzyme immobilization on nanomatrix supports and their intracellular delivery.

Enzymes are one of the foundations and regulators for all major biological activities in living bodies. Hence, enormous efforts have been made for enhancing the efficiency of enzymes under different conditions. The use of nanomaterials as novel carriers for enzyme delivery and regulating the activities of enzymes has stimulated significant interests in the field of nano-biotechnology for biomedical applications.

Internalization and effects on cellular ultrastructure of nickel nanoparticles in rat kidneys.

Since nanoparticles (NPs) are beginning to be introduced in medicine and industry, it is mendatory to evaluate their biological side-effects, among other things. The present study aimed to investigate the pathways by which nickel nanoparticles (NiNPs) enter nephrons and to evaluate their localization and effects on cellular ultrastructure. Rats were injected intraperitoneally with 20 nm NiNPs (20 mg/Kg/b.