Different duration of exposure to a pulsed magnetic field can cause changes in mRNA expression of apoptotic genes in oleic acid-treated neuroblastoma cells.

PURPOSE: Neuroblastoma, a prevalent childhood tumor, poses significant challenges in therapeutic interventions, especially for high-risk cases. This study aims to fill a crucial gap in our understanding of neuroblastoma treatment by investigating the potential molecular impacts of short- and long-term pulsed magnetic field exposure on the neuronal apoptosis mechanism in an in vitro model of neuroblastoma treated with oleic acid (OA). MATERIALS AND METHODS: Cells were cultured and divided into six following experimental groups: (I) Nontreated group (NT); (II) OA-treated group (OA); (III) Group treated with OA after being exposed to the pulsed magnetic field for 15-min (15 min PEMF + OA); (IV) Group treated with OA after being exposed to the pulsed magnetic field for 12 h (12 h PEMF + OA); (V) Group exposed to the pulsed magnetic field for 15 min (15 min PEMF); and (VI) Group exposed to the pulsed magnetic field for 12 h (12 h PEMF). Cell viability, rates of apoptosis, and mRNA levels of key apoptotic genes (TP53, Bcl2, Bax, and Caspase-3) were assessed. RESULTS: Significant reductions in cell viability were observed, particularly in the group treated with OA following long-term pulsed magnetic field exposure. Flow cytometry revealed elevated apoptosis rates, notably in the early stages of apoptosis. qRT-PCR analysis demonstrated increased expression of cleaved Caspase-3, Bax/Bcl2 ratio, and TP53 in cells treated with OA following long-term pulsed magnetic field exposure, signifying enhanced apoptotic pathways. CONCLUSIONS: The findings indicate that long-term pulsed magnetic field exposure and OA treatment exhibit potential synergistic effects leading to the induction of apoptosis in SH-SY5Y cells. We have concluded that stimulations of pulsed magnetic field have the potential to serve as an adjuvant therapy for oleic acid-based treatment of neuroblastoma.

Electromagnetic field exposure to human head model with various metal objects at sub-6 GHz frequencies.

In recent years, the interactions of metal objects in human body with electromagnetic fields caused by devices working at fifth-generation (5G) frequencies have been studied by various researchers. A motivation behind this research was to evaluate the human body absorption of electromagnetic energy operating at sub-6 GHz 5G applications. According to this, the specific absorption rate (SAR) caused by new generation mobile phones was investigated in human heads wearing metal-framed spectacles and having metallic implants or earrings to analyse electromagnetic field exposure. A realistic human head model, including some metal objects, was numerically calculated, and analysed in terms of non-ionizing dosimetry. Simulations were carried out with the finite integration technique (FIT) based commercial software in the frequencies of 0.9, 1.8, 2.1, 2.45, 3.5 and 5 GHz, respectively. The maximum SAR of 14 × 10-5 W/kg for 10 g average tissue was calculated at 2.45 GHz frequency in the head model with earrings. The highest electric field strength of 0.52 V/m was observed at a 1.8 GHz frequency in the head model with all metal objects equipped. Results show that metal objects such as spectacles, dental implants and earrings can cause an increase in the SAR values for external biological tissues, and metal objects can behave as a kind of shield for deeper tissues. However, the obtained values are below the limits of international organisations.

Dosimetry analysis of the magnetic field of underground power cables and magnetic field mitigation using an electromagnetic shielding technique.

Non-ionizing dosimetry investigations of extremely low frequency (ELF) magnetic fields that are generated by underground power cables as well as the minimization of their health effects are significant topics handled by numerous researchers. In this study, ELF magnetic fields and current densities caused by three-phased underground transmission lines induced in the human model were examined utilizing both analytical and numerical methods. Analyses were carried out using a two-dimensional problem scenario for the comprehensive head and body model. The results of the finite element method (FEM)-based simulation studies and the analytical calculations are consistent with each other. Moreover, a magnetic field shielding method utilizing conductive material was presented in the study. The shielding technique performed with copper material was carried out to mitigate the magnetic field and possible dosimetry hazards in the ELF region. The proposed shield was a 4-mm reverse U-shaped copper material.

MEASUREMENT AND ANALYSIS OF ELECTRIC AND MAGNETIC FIELD STRENGTH IN GRID-TIED PHOTOVOLTAIC POWER SYSTEM COMPONENTS.

In this study, electric field and magnetic field strengths at 50 Hz are measured in a solar power plant located far from residential areas, and the measurement results near various sources of the electric and magnetic fields in the power plant are presented. Although the measured values for the electric field caused by the solar panel range between 0.07 and 1.33 V/m, the measured values for the magnetic field by the solar panel range between 0.037 and 0.19 µT. In front of the inverter, the measured value of the electric field reaches 0.7 V/m, whereas the measured value of the magnetic field reaches 2.2 µT. The results are presented and evaluated in light of the exposure limits to electromagnetic fields published by international organisations.

An Evaluation of the Genotoxic Effects of Electromagnetic Radiation at 900 MHz, 1800 MHz, and 2100 MHz Frequencies with a SMART Assay in Drosophila melanogaster.

With the development of today's technology, the electromagnetic radiation spread by mobile phones and base stations is also rapidly increasing, and this causes serious concerns about the environment and human health. The Drosophila model organism is widely used in genetic toxicology studies because its genome is highly similar to the genes identified in human diseases. In this study, the genotoxic effects of radiofrequency electromagnetic radiation were evaluated by the wing Somatic Mutation and Recombination Test (SMART) in Drosophila melanogaster at 900 MHz, 1800 MHz, and 2100 MHz. The SMART method is based on the observation of genetic changes occurring in the trichomes of the Drosophila wings appearing as mutant clones under the microscope. Throughout the study, total clone parameters were evaluated by exposing the Drosophila larvae to electromagnetic fields for two, four, and six hours per day for two days. As a result of the study, it was observed that the number of mutant clones was statistically increased according to the negative control group in all applications except for the six-hour application at 1800 MHz.

Possible effects of different doses of 2.1 GHz electromagnetic radiation on learning, and hippocampal levels of cholinergic biomarkers in Wistar rats.

The present study evaluated whether short-term exposure to different doses of 2.1 GHz radiofrequency electromagnetic radiation (RF-EMR) has different effects on rats' behaviour and hippocampal levels of central cholinergic biomarkers. Animals were divided into three equal groups namely; group 1 was sham-exposed group, group 2-3 were exposed to 45 V/m and 65 V/m doses of 2.1 GHz frequency for 1 week respectively. Numerical dosimetry simulations were carried out. Object location and Y-maze were used as behavioural tasks. The protein and mRNA expression levels of AChE, ChAT, and VAChT, in the hippocampus were tested using Western Blotting and Real-Time PCR. The impairment performance of rats subjected to 65 V/m dose of 2.1 GHz RF-EMR in both object location and Y-maze tasks was observed. The hippocampal levels of AChE, ChAT, and VAChT, were significantly lower in rats exposed to 65 V/m dose of 2.1 GHz RF-EMR than others. The stronger effect of "65 V/m" dose on both rat's hippocampal-dependent behavioural performances and hippocampal levels of cholinergic biomarkers may be due to the stronger effect of "65 V/m" dose where rats' snouts were located at the nearest distance from the monopole antenna. Furthermore, the simulated SAR values were high for 65 V/m electric-field strengths. For the first time, we report the potential dose-dependent effects of short-term exposure to 2.1 GHz radiation on rat's behavioural performances as well as hippocampal levels of cholinergic biomarkers. Further studies are needed to understand the mechanisms by which RF-EMR influences the function of the central cholinergic system in the brain.