A 50 Hz magnetic field affects hemodynamics, ECG and vascular endothelial function in healthy adults: A pilot randomized controlled trial

Application of exposure to 50/60 Hz magnetic fields (MFs) has been conducted in the treatment of muscle pain and fatigue mainly in Japan. However, whether MFs could increase blood flow leading to muscle fatigue recovery has not been sufficiently tested. We investigated the acute effects of a 50 Hz sinusoidal MF at Bmax 180 mT on hemodynamics, electrocardiogram, and vascular endothelial function in healthy young men. Three types of regional exposures to a 50 Hz MF, i.e., forearm, upper arm, or neck exposure to MF were performed. Participants who received three types of real MF exposures had significantly increased ulnar arterial blood flow velocity compared to the sham exposures. Furthermore, after muscle loading exercise, MF exposure recovered hemoglobin oxygenation index values faster and higher than sham exposure from the loading condition. Moreover, participants who received real MF exposure in the neck region had significantly increased parasympathetic high-frequency activity relative to the sham exposure. The MF exposure in the upper arm region significantly increased the brachial artery flow-mediated dilation compared to the sham exposure. Computer simulations of induced in situ electric fields indicated that the order-of-magnitude estimates of the peak values were 100–500 mV/m, depending on the exposure conditions. This study provides the first evidence that a 50 Hz MF can activate parasympathetic activity and thereby lead to increase vasodilation and blood flow via a nitric oxide-dependent mechanism. Trial registration: UMIN Clinical Trial Registry (CTR) UMIN000038834. The authors confirm that all ongoing and related trials for this drug/intervention are registered.

MANIFESTATIONS OF SUBACUTE SYSTEMIC TOXICITY OF LEAD OXIDE NANOPARTICLES IN RATS AFTER AN INHALATION EXPOSURE

Outbred white female rats were exposed to an aerosol of lead oxide nanoparticles in a nose-only inhalation setup at an average concentration of 1.30 ± 0.10 mg / m3 during 5 days for 4 hours a day. In parallel, the control group of rats was subjected to sham exposure under similar conditions. The deposition of nanoparticles in the lungs and in the olfactory region of the brain was detected using transmission electron microscopy. Some disorders of the body state were detected in the exposed group, some of which can be considered as the result of a lead-specific toxic effect (an increase in the proportion of reticulocytes and in urinary excretion of δ-aminolevulinic acid), and others - the result of nanoparticles circumventing the blood-brain barrier (axon demyelination, vacuolization of the neurons’ cytoplasm).

1Hz and 100mT Electromagnetic Field Induces Apoptosis in Breast Cancer Cells Through Up-Regulation of P38 and P21

Introduction: Breast cancer is the most common cause of cancer-related death among women. Recently, extremely low-frequency electromagnetic field (ELF-EMF) has been proposed as a new interfering agent with future therapeutic potentials. Many studies have revealed that cellular processes such as apoptosis in breast cancer are affected by ELF-EMFs. However, more researches are needed to clarify the underlying mechanism of action for these fields. In this study, the apoptotic effect of ELF-EMF on the MC4L2 cell line was examined and the mRNA expression level of the P21 and P38 genes were further investigated. Methods: A triple-positive mouse breast cancer cell line (MC4L2) was purchased from the Genetic Resource Center (Iran). This study was performed on two groups of ELF-EMF exposure (100mT/1 Hz for 5 days, 120 min each day) and sham exposure. Cell viability and apoptosis rate of both the exposure and sham exposure groups weredetermined by flow cytometry. Alterations in the P21 and P38 mRNAs expression levelswere investigated; using real-time PCR. Results: ELF-EMF exposure induced 30% apoptosis in MC4L2 cells compared with the control group. The mRNA expression level of P38 and P21 was significantly increased after ELF-EMF exposure compared to the control group. Conclusions: ELF-EMF induces apoptosis in the MC4L2 triple-positive cell line. Furthermore, this exposure affects important gene expression involved in the cell cycle. Our data propose that ELF-EMF in a specific time, intensity, and frequency could be beneficial for breast cancer treatment. However, more studies are required to confirm our findings.

Evaluation of Blast Overpressure Exposure Effects on Concentration of Antibiotics in Mice

ABSTRACT Objective Infection as sequelae to explosion-related injury is an enduring threat to our troops. There are limited data on the effects of blast on antibiotic pharmacokinetics (PK), pharmacodynamics (PD), and efficacy. The observational study presented here is our Institute’s first attempt to address this issue by combining our existing interdepartmental blast, infection modeling, and in vivo PK/PD capabilities and was designed to determine the PK effects of blast on the first-line antibiotic, cefazolin, in an in vivo mouse model. Methods A total of 160 male BALB/c mice were divided to sham and blast (exposed to blast overpressure of 19 psi) in two biological replicates. At 1 hour after blast/sham exposure, the animals received IV injection of cefazolin (328 mg/kg). Animals were euthanized at 3 minutes, 10 minutes, 15 minutes, 30 minutes, 1 hour, 3 hours, 6 hours, or 10 hours after the injection. Plasma and liver were analyzed for concentration of cefazolin using mass-spectrometry. Results We observed increases in the concentration of cefazolin in the plasma and liver of blast exposed animals at later time points and increase in elimination half-life. Conclusion Our results indicate that blast-induced physiologic changes significantly influence cefazolin PK and suggest that efficacy could be affected in the context of the blast; assessment of efficacy and PD effects require further investigation. Metabolic changes resulting from blast may influence other classes of antibiotics and other therapeutics used with these injuries. Therefore, this may have important treatment considerations in other areas of military medicine.

Human Psychomotor Performance Under the Exposure to Mobile Phones-Like Electromagnetic Fields

The first studies on humans addressing cognitive functioning changes as a consequence of radiofrequency (RF) EMFs exposure date back to almost 20 years ago. The effects on human behavior showed in those pioneering works indicated an improvement of performance under the exposure to the signal, compared with sham exposure. These first and striking results were not fully replicated by subsequent studies that were characterized by a more methodological robustness and attention to exposure aspects. In accordance with this view, latest reviews and metanalyses have confirmed the paucity of evidence and the lack of reliability of psychomotor and cognitive effects of acute RF EMF exposure on human volunteers, particularly when assessed in well controlled laboratory settings. Thus, despite the public opinion about potential biologic effects of acute RF EMFs irradiation, it can be concluded that to date there is substantial lack of evidence about a negative influence of non-ionizing radiations on cognitive functioning in humans.

Human Psychomotor Performance Under the Exposure to Mobile Phones-Like Electromagnetic Fields

The first studies on humans addressing cognitive functioning changes as a consequence of radiofrequency (RF) EMFs exposure, date back to almost 20 years ago. The effects on human behaviour showed in those pioneering works indicated a somewhat improvement of performance under the exposure to the signal, compared with sham exposure. These first and striking results were not fully replicated by subsequent studies that were characterized by a more methodological robustness and attention to exposure aspects. In accordance with this view, latest reviews and metanalyses have confirmed the paucity of evidence and the lack of reliability of psychomotor and cognitive effects of acute RF EMF exposure on human volunteers, particularly when assessed in well controlled laboratory settings. Thus, despite the public opinion about potential biologic effects of acute RF EMFs irradiation, it can be concluded that to date there is substantial lack of evidence about a negative influence of non-ionizing radiations on cognitive functioning in humans.

Radiofrequency signal affects alpha band in resting electroencephalogram

The aim of the present work was to investigate the effects of the radiofrequency (RF) electromagnetic fields (EMFs) on human resting EEG with a control of some parameters that are known to affect alpha band, such as electrode impedance, salivary cortisol, and caffeine. Eyes-open and eyes-closed resting EEG data were recorded in 26 healthy young subjects under two conditions: sham exposure and real exposure in double-blind, counterbalanced, crossover design. Spectral power of EEG rhythms was calculated for the alpha band (8–12 Hz). Saliva samples were collected before and after the study. Salivary cortisol and caffeine were assessed by ELISA and HPLC, respectively. The electrode impedance was recorded at the beginning of each run. Compared with the sham session, the exposure session showed a statistically significant ( P < 0.0001) decrease of the alpha band spectral power during closed-eyes condition. This effect persisted in the postexposure session ( P < 0.0001). No significant changes were detected in electrode impedance, salivary cortisol, and caffeine in the sham session compared with the exposure one. These results suggest that GSM-EMFs of a mobile phone affect the alpha band within spectral power of resting human EEG.

Sevoflurane Anesthesia Does Not Impair Acquisition Learning or Memory in the Morris Water Maze in Young Adult and Aged Rats

Background Sevoflurane has been found to increase apoptosis and pathologic markers associated with Alzheimer disease, provoking concern over their potential contribution to postoperative cognitive dysfunction. Methods The effects of anesthesia with 1 minimum alveolar concentration of sevoflurane for 4 h or sham exposure on cognition were investigated in young adult and aged (20-24 months) rats at 1, 4, and 12 weeks postexposure. Spatial reference memory acquisition and retention were tested in the Morris water maze task. Latency to locate the hidden platform and swim speed were determined and compared between treatments. Results Sevoflurane anesthesia significantly reduced latency to find the hidden platform in both young adult (n = 10 per treatment, P &lt; 0.0001) and aged rats (n = 7 per treatment, P &lt; 0.0001) when tested 1 week after exposure. In young rats only, this improved acquisition learning was maintained at 4 (P = 0.003) but not at 12 weeks postexposure (P = 0.061). There were no differences in swim speed or in open field exploration between groups (no confounding effects of stress or locomotion). Retention memory measured using probe trials was not affected by exposure to sevoflurane in young adult or aged rats. Conclusion Sevoflurane anesthesia did not impair acquisition learning and retention memory in young adult or aged rats.

Pain Behavior Changes Following Disc Puncture Relate to Nucleus Pulposus Rather than to the Disc Injury Per Se: An Experimental Study in Rats

It has previously been demonstrated that disc puncture in the rat induced changes in grooming and wet dog shakes, two behavioral changes that may be linked to discomfort and neuropathic pain. In this study the aim was to separate the effects of disc injury and the epidural presence of nucleus pulposus. Following anesthesia, the L4-5 disc was exposed using a dorsal approach. Ten rats received a superficial disc injury without nucleus pulposus leakage and ten rats received nucleus pulposus from a donor rat without disc injury. In ten animals the L4-5 disc was punctured using a ventral approach, with 10 corresponding controls. Spontaneous behavior was assessed after surgery. The data was matched to historical control of dorsal sham surgery and disc puncture. The study showed that the effects of nucleus pulposus were more pronounced than the effects induced by the disc injury. Ventral disc puncture did not induce any behavioral changes different from sham exposure. In conclusion, the data from the study indicate that behavioral changes induced by disc puncture are more likely to relate to the epidural presence of nucleus pulposus than the disc injury per se.