Mechanisms of the Effects of Zinc Oxide Nanostructures on Living Cells

Nowadays, nanotechnology and nanostructures, which are particles smaller than 100 nm in size at least in one dimension, are being widely used in various industries and consumer products, biomedical applications and environments. Unique properties of Zinc oxide (ZnO) nanostructures offer technological advantages for a variety of industrial and consumer products as well as show promise for biomedical application. They are used as an antibacterial agent in food packaging, such as UV absorbent in cosmetics and sunscreens. However, high concentrations of ZnO nanostructures have toxic effects on living organisms. The toxic effect of these nanostructures depends on target cell type, size, structure, and surface properties of nanostructures, as well as exposure routes. In this article, we discuss the toxic effect of ZnO nanostructures and different mechanisms including ROS production and the resulting oxidative stress, genomic toxicity, changes in gene expression and following protein production, epigenetic changes and inflammatory responses and apoptosis. Also, we will mention many in vivo studies about this nanoparticle

Mechanistic and kinetic aspects of Natamycin interaction with serum albumin using spectroscopic and molecular docking methods

Natamycin (NT) is a polyene natural antimycotic, which has an antimicrobial effect against yeasts and molds and is used as a preservative in the food industry. In the present study, we evaluated NT interaction with bovine serum albumin (BSA) through surface plasmon resonance (SPR) and several spectroscopic techniques, which are accompanied by a molecular docking study. According to the results, the intensity of BSA fluorescence decreased by adding different concentrations of NT. The fluorescence quenching results showed that NT reduces the intensity of BSA fluorescence by forming a complex with BSA through a hybrid quenching. Binding constant decreases from 18.73 to 2.13 (102 M−1) with increasing temperature, which indicates a decrease in complex formation owing to the interaction of NT with BSA. Negative values of ΔH° and ΔS° confirmed that van der Waals forces and hydrogen bonds are the basic forces in the interaction of NT with BSA. Moreover, increasing the equilibrium constants values with increasing temperature indicated that BSA binding to NT decreased. Finally, BSA interaction occurring with NT through Ser 109, Asp 111, Lys 114, Leu 115, Glu 424, and Arg 458 have been verified via molecular docking analysis. Attained results via SPR and fluorimetry showed that the binding constant between BSA and NT decreased when the temperature was raised

The cardiac effects of carbon nanotubes in rat

Introduction: Carbon nanotubes (CNTs) are novel candidates in nanotechnology with a variety of increasing applications in medicine and biology. Therefore the investigation of nanomaterials’ biocompatibility can be an important topic. The aim of present study was to investigate the CNTs impact on cardiac heart rate among rats. Methods: Electrocardiogram (ECG) signals were recorded before and after injection of CNTs on a group with six rats. The heart rate variability (HRV) analysis was used for signals analysis. The rhythm-to-rhythm (RR) intervals in HRV method were computed and features of signals in time and frequency domains were extracted before and after injection. Results: Results of the HRV analysis showed that CNTs increased the heart rate but generally these nanomaterials did not cause serious problem in autonomic nervous system (ANS) normal activities. Conclusion: Injection of CNTs in rats resulted in increase of heart rate. The reason of phenomenon is that multiwall CNTs may block potassium channels. The suppressed and inhibited IK and potassium channels lead to increase of heart rate

Emerging applications of phage therapy and fecal virome transplantation for treatment of Clostridioides difficile infection: challenges and perspectives

Abstract Clostridioides difficile, which causes life-threatening diarrheal disease, is considered an urgent threat to healthcare setting worldwide. The current standards of care solely rely on conventional antibiotic treatment, however, there is a risk of promoting recurrent C. difficile infection (rCDI) because of the emergence of antibiotic-resistant strains. Globally, the alarming spread of antibiotic-resistant strains of C. difficile has resulted in a quest for alternative therapeutics. The use of fecal microbiota transplantation (FMT), which involves direct infusion of fecal suspension from a healthy donor into a diseased recipient, has been approved as a highly efficient therapeutic option for patients with rCDI. Bacteriophages or phages are a group of viruses that can infect and destroy bacterial hosts, and are recognized as the dominant viral component of the human gut microbiome. Accumulating data has demonstrated that phages play a vital role in microbial balance of the human gut microbiome. Recently, phage therapy and fecal virome transplantation (FVT) have been introduced as promising alternatives for the treatment of C. difficile -related infections, in particular drug-resistant CDI. Herein, we review the latest updates on C. difficile- specific phages, and phage-mediated treatments, and highlight the current and future prospects of phage therapy in the management of CDI