Different effects of alternating electric currents (AC) on biological materials have been observed depending on the frequency used. Extremely low frequencies (less than 1 KHz) produce electro-endocytosis at 500 Hz because of membrane depolarization. Intermediate frequencies coincide with tiny particle alignments and cell rotations (also known as the pearl chain effect), thus leading to the tumor-treating fields at 100–300 KHz. High frequencies (i.e., above several MHz) cause tissue heating to predominate due to the dielectric losses. This study investigates how exposure to a wide range of AC electric field frequencies affects the permeability and viability of hepatocellular carcinoma HEPG2 cells. With two silver/silver chloride electrodes, the cells were exposed to a square pulse with a magnitude of 0.4 V/cm at various frequencies between 1 Hz and 1 MHz. A dielectric properties measurement, flow cytometry analysis, fluorescent microscopy, and a polymerase chain reaction (PCR) gene expression analysis were performed. The results showed that all the exposed groups experienced a great reduction in the normal cells, with a clear increase in necrosis and apoptosis compared to the control group. It was noticed that the anti-tumoral effect of the examined frequency range was maximum at 10 KHz and 100 KHz. The permeability was increased in the groups exposed to frequencies above 1 kHz. The viability and permeability results were correlated to the electric relative permittivity, electric conductivity, and gene expression of cyclins A, B, and E.

Performing their functions as transporters of oxygen and carbon dioxide in the body, human erythrocytes constantly circulate and are exposed to the constant influence of various substances, including nutrients, drugs, medical devices covered with coatings, etc. Therefore, we aim to investigate the biophysical behavior of erythrocytes obtained from healthy volunteers to observe their morphological type changes, alterations in the zeta potential, the electrical conductivity of the erythrocytes in suspensions, and hemolysis in percentages during cells senescence, both in presence and in absence of natural polyelectrolytes pectin (PE) and chitosan (Chi) in form of multilayer films (PEM-films). Being constructed using the layer–by–layer technique, films are an object of interest of many researchers because of their high potential to be incorporated in biomedicine. By applying optical profilometry, electrophoretic light scattering, and spectrophotometry, we tested the polyelectrolytes for any potential harm on the erythrocytes. Based on our results and the one-way analysis of variance (ANOVA) statistical analysis, we reached the conclusion that the above-mentioned polyelectrolytes were harmlessness; therefore, PE and Chi are suitable substances to implement in the clinical practice in the form of drug delivery carriers and medical devices coatings, thereby directly contacting with the human blood.

This study focuses on a simple, non-toxic, and environmentally friendly method for the green synthesis of silver nanoparticles using Dicranum scoparium moss extract. It includes the characterization of the biosynthesized nanoparticles and an evaluation of their antibacterial, antifungal, and anticancer activities. Transmission electron microscopy (TEM) and dynamic light scattering (DLS) analyses confirmed that the biosynthesized silver nanoparticles were within the nanoscale range (50–100 nm) and exhibited an irregular morphology. The biogenic nanoparticles demonstrate antibacterial activity against bacterial strains Staphylococcus aureus, Bacillus mesentericus, Escherichia coli, and Pseudomonas aeruginosa. The results indicate a pronounced antibacterial activity against E. coli and P. aeruginosa compared to the tested Gram-positive bacteria, which is attributed to differences in the bacterial cell wall structure. Additionally, the green synthesized silver nanoparticles inhibited the growth of Mucor plumber, Geotrichum candidum, Cladosporium herbarum, and Aspergillus flavus mold fungi. Additionally, they expressed considerable cytotoxic properties against cancer cells.

Subcutaneous (SC) sustained release is an important drug delivery system (DDS) for antibody/protein drugs because it reduces dosing frequency. This review discusses formulations and biophysical parameters that affect the pharmacokinetics (PK) of DDSs. For example, SC injectable microspheres and polymeric hydrogels, as well as intradermal microneedles, suppress denaturation in loading and burst release of drugs [growth hormone, interferon-α2b, bevacizumab, and single-chain antibody fragment (scFv)]. These DDSs significantly prolong half-life (t_1/2) in plasma with low maximum concentration (C_max) and low relative bioavailability after SC dosing to animals and/or humans. Formulation parameters, such as (1) drug loading amount, (2) drug diffusion in DDS, (3) interactions of drugs with polymers, and (4) microneedle design, likely contribute to their PK profiles. This review also discusses the effects of many biophysical parameters on PK, including (5) in vivo behavior of polymers (swelling, aggregation, dissolution, and accumulation), (6) drug interactions with extracellular matrix and hypodermis diffusion, (7) drug unfolding, (8) hypodermic concentration of drugs, inherent proteins, and cells, (9) drug absorption through lymphatic or blood vessels, (10) degradation of drugs/polymers by proteases/phagocytic cells, (11) FcRn-mediated recycling, (12) FcγR-mediated endocytosis, and (13) target-mediated drug clearance. For safe dosing, (14) skin’s thickness/viscoelastic properties and variations and (15) skin’s recovery are also important factors. Consideration of these effects will increase the developmental speed and success of many SC sustained-release DDSs of antibody/protein drugs.

Candida auris is an emerging pathogenic yeast. In order to investigate possible light-based disinfection systems or therapeutic approaches, this study examined the formation of possible photosensitizers under different growth conditions. The yeast was cultivated under aerobic conditions in YEPG medium and minimal medium with 10% NaCl. 2D fluorescence spectroscopy (15 excitation wavelengths from 320 to 450 nm) at different time points was performed to calculate the concentrations and proportions of dry mass of various fluorophores. Comparing the different growth conditions, higher concentrations of porphyrins were observed with minimal medium + 10% NaCl than with the YEPG medium. When determining the concentrations of different fluorophores over time, different dynamics could be observed for both aerobic growth conditions. For both growth conditions, NADH, followed by thiamine and lumichrome, exhibited the highest concentrations; coproporphyrin III showed the lowest.

Ionizing radiation is a common health risk encountered by healthcare professionals. Previous studies highlighted the potential adverse effects of X-ray exposure, such as metabolic dysfunctions, radiation-induced biological changes, and a susceptibility to infection. The present study examined the long-term effects of radiation exposure on the hematopoietic system and thyroid functions. A cohort of 40 healthcare professionals of various professions working in the cardiac catheterization center at Azadi Teaching Hospital were recruited for this study. After their consent, the necessary data were taken, and blood specimens were collected for the laboratory investigations. The recruits were divided based on x-ray exposure into pre- and post-exposure groups. Concerning the hematological parameters, no significant differences were observed between the groups, except MCH, which was statistically elevated in the post-exposure group (p = 0.000). Among the thyroid hormones, only free T4 was significantly increased in the post-exposed subjects (p = 0.000) as compared to non-exposed controls. Moreover, a positive correlation was observed between the ionizing radiation exposure dosage and T4 elevation (r = 0.362, p = 0.02). The findings collectively highlight the remarkable impact of long-term radiation exposure on thyroid functions and some hematological parameters. Therefore, regular monitoring of health professionals is suggested to avoid the detrimental effects of radiation on human health.

Electrical bioimpedance (BI) was proposed as an easy and cheap technique to monitor different physiological parameters. However, its clinical applications are minimal due to the low resolution and difficulties in discriminating between different tissue types. Nanoparticles have also been extensively investigated for their practical use. Graphene oxide (GO) has shown acceptable biocompatibility. The objective of this work was to assess the possibility of using GO to enhance bioimpedance measures in ex vivo models. GO was suspended in medical-grade solutions and injected into the tissues. BI was recorded at 12.5, 25, 50, and 100 kHz. Bode impedance plots evidenced statistically significant differences in tissue impedance before and after injections. Likewise, data adjustment to an equivalent electrical circuit showed that GO accumulates mainly in the extracellular space and, to some extent, at the cytoplasmatic membrane, and the accumulation is tissue specific. The latter suggests the possibility of using GO as a contrast agent to discriminate between different tissue types using BI.