Stevens P · 2007
Researchers studied whether exposure to a 0–5 µT magnetic field at EEG alpha-band frequencies (8–12 Hz) would affect emotional state. Participants reported a change in emotional state following exposure, and a decrease in global field power was observed. The frontal alpha-asymmetry that would physiologically indicate a directly induced emotional state was absent, and researchers suggested that participant experiences were due to an interpretation of the effects of MF exposure.
Shin EJ et al. · 2007
Researchers examined the role of dopaminergic receptors in behavioral changes induced by extremely low frequency magnetic fields (ELF-MF). Exposure to ELF-MF at 2.4 mT for 1 hour per day, for one or seven days, enhanced locomotor activity in a time-dependent manner. The results suggest that ELF-MF-induced behavioral responses are, at least in part, mediated by activation of dopamine D1-like receptors.
Manikonda PK et al. · 2007
Researchers exposed rats to 50 Hz magnetic fields at 50 and 100 μT intensities for 90 days and then examined hippocampal tissue. Compared to controls, ELF exposure was associated with increased intracellular calcium levels and changes in the activity of several calcium-related enzymes. Binding to NMDA receptors was also found to be decreased in exposed rats. The researchers suggested that perturbed neuronal functions caused by ELF exposure may involve altered calcium signaling contributing to aberrant NMDA receptor activities.
Jadidi M et al. · 2007
Researchers used a water maze to evaluate how magnetic field exposure affects consolidation and retrieval of spatial memory in rats. Exposure to a 50 Hz, 8 mT magnetic field for 20 minutes immediately after training impaired retention performance, but exposure at 2 mT did not. Exposure given shortly before retention testing had no effect on performance.
Del Giudice E et al. · 2007
Researchers tested whether low-frequency electromagnetic field exposure could affect amyloidogenic processes in cultured cells. They exposed H4 neuroglioma cells that stably overexpress human mutant amyloid precursor protein to a 3.1 mT 50 Hz field. Overnight exposure significantly increased secretion of amyloid-beta peptide, including the isoform Aβ 1–42, without affecting cell survival.
Che Y, Sun H, Cui Y, Zhou D, Ma Y. · 2007
Researchers examined the effects of a 50 Hz magnetic field at 1 mT intensity on learning and memory in Lohmann brown domestic chicks using a detour learning task. Chicks exposed for 20 hours per day showed a significant impairment in detour learning, while those exposed for 50 minutes per day showed no effect.
Carrubba S, Frilot C, Chesson AL, Marino AA. · 2007
Regel SJ et al. · 2007
Researchers exposed the heads of 15 healthy male subjects for 30 min prior to sleep to a pulse-modulated EMF signal at different intensities or a sham condition, in a double-blind, crossover design. The active exposure levels used peak spatial specific absorption rates of 0.2 W kg–1 and 5 W kg–1. Sleep EEG analysis showed a dose-dependent increase of power in the spindle frequency range in non-REM sleep, while sleep architecture was not affected. Reaction speed slowed with increasing field intensity in the 1-back task, but accuracy in the CRT and N-back tasks was not affected in a dose-dependent manner.
Ning W, Xu SJ, Chiang H, Xu ZP, Zhou SY, Yang W, Luo JH · 2007
Researchers cultured hippocampal neurons from rats and exposed them to GSM 1800 MHz microwaves at either 2.4 or 0.8 W/kg for 15 minutes each day from DIV6 to DIV14. At 2.4 W/kg, the density and mobility of dendritic filopodia at DIV8 and the density of mature spines at DIV14 were significantly decreased, and the average length of dendrites per neuron at DIV10 and DIV14 was also decreased. Dendritic arborization was unaltered in the exposed neurons, and no significant changes were found in neurons exposed to 0.8 W/kg.
Meral I et al. · 2007
In brain tissue, the MDA level increased and GSH level and CAT enzyme activity decreased in EMF-exposed guinea pigs, while vitamins A, E, and D3 levels did not change. In blood, MDA, vitamins A, D3, and E levels, and CAT enzyme activity increased, while GSH level decreased in the EMF-exposed guinea pigs.
Kumlin T et al. · 2007
Researchers exposed young male Wistar rats to a 900 MHz mobile phone signal for 2 h/day on 5 days/week. After 5 weeks of exposure at whole-body average specific energy absorption rates of 0.3 or 3.0 W/kg or sham exposure, rats were assessed for behavioral and morphological changes. No degenerative changes, dying neurons, or effects on blood-brain barrier leakage were detected, and no group differences appeared in the open-field, plus maze, or acoustic startle response tests. In the water maze test, significantly improved learning and memory were detected in rats exposed to RF fields.
Hung CS, Anderson C, Horne JA, McEvoy P · 2007
Researchers exposed 10 healthy young adults to talk, listen, standby, or sham signal modes for 30 minutes, then gave them a 90-minute sleep opportunity. Sleep latency after talk mode was markedly and significantly delayed beyond listen and sham modes. This condition effect was also evident in 1–4 Hz EEG frontal power, a frequency range described as particularly sensitive to sleep onset. There was no condition effect for subjective sleepiness.
Brillaud E, Piotrowski A, de Seze R · 2007
Researchers measured GFAP expression in rat brains 2, 3, 6, and 10 days after a single 15-minute 900 MHz GSM exposure at a brain averaged SAR of 6 W/kg. A statistically significant increase in GFAP stained surface area was observed 2 days after exposure in the frontal cortex and the caudate putamen. A smaller statistically significant increase was noted 3 days after exposure in those same areas and in the cerebellum cortex. The researchers concluded this was a temporary effect, probably due to a hypertrophy of glial cells, and noted that whether the effect could be harmful remains to be studied.
Zhao R, Zhang S, Xu Z, Ju L, Lu D, Yao G. · 2007
Researchers investigated whether 1800 MHz radiofrequency electromagnetic fields could influence gene expression in rat neurons. Among 1200 candidate genes, 24 were up-regulated and 10 were down-regulated after 24 hours of intermittent exposure at a SAR of 2 W/kg. The researchers concluded that gene expression in rat neurons could be altered by exposure to radiofrequency electromagnetic fields under their experimental conditions.
Buttiglione M et al. · 2007
Researchers exposed human neuroblastoma SH-SY5Y cells to 900 MHz radiofrequency radiation at 1 W/kg to study effects on gene expression and cell-cycle control. Short-term exposures produced a transient increase in Egr-1 mRNA levels along with activation of the MAPK subtypes ERK1/2 and SAPK/JNK. Exposure had an anti-proliferative effect, and a significant G2-M cell-cycle arrest was observed, with signs of apoptosis appearing after 24 hours. A significant decrease in mRNA levels of Bcl-2 and survivin genes, both linked to signaling between G2-M arrest and apoptosis, was also observed.
Unknown authors · 2006
Rats were given 10-min access to a novel saccharin solution and then restrained within a 14-T magnet for 30 min. In experiment 1, males were compared with females across the estrous cycle after a single MF exposure. Females circled more and acquired a more persistent CTA than males; circling was highest on the day of estrus. In experiment 2, the effects of three MF exposures were compared among intact rats, ovariectomized females, and ovariectomized females with steroid replacement. Compared with intact rats, ovariectomy increased circling; estrogen replacement blocked the increase, and males acquired a stronger initial CTA but extinguished faster than intact or ovariectomized females.
Unknown authors · 2006
Researchers screened genes responsive to brief magnetism in cultured rat hippocampal neurons using differential display analysis. They identified Ntan1 as a magnetism-responsive gene in rat brain. Northern blot analysis showed that Ntan1 mRNA increased about three-fold after 3 hours in response to brief magnetism. Brief magnetism induced degradation of MAP2 without affecting cell morphology or viability, and this degradation was prevented by a selective inhibitor of the 26S proteasome. Overexpression of Ntan1 using a recombinant adenovirus vector decreased MAP2 protein expression in hippocampal neurons.
Unknown authors · 2006
Unknown authors · 2006
Orientation and pain sensitivity are affected by low-frequency magnetic fields near Earth's field strength. These effects often depend on visible light being present. Mice in a shielded dark environment showed altered nociception, but visible light during shielding eliminated most shielding effects.
Unknown authors · 2006
The aim of the studies was to investigate possible alterations in the cellular and neuronal systems of electrohypersensitive persons' skin. Age- and sex-matched persons without symptoms served as controls. Immunohistochemistry with antisera to previously characterized marker substances was used. Preliminary data indicate various alterations in the skin of electrohypersensitive persons.
Unknown authors · 2006
The hypothesis predicts optimal ameliorating effects on experimental allergic encephalomyelitis at derived intensities of about 35 and 70 nT and a frequency of 7 Hz. These predictions were congruent with prior rat experiments using magnetic field strengths of about 1-5000 nT at 0.5, 7, 40, or 60 Hz. The model proposes that weaker fields in the nanoTesla to picoTesla range would optimally affect micromolar melatonin concentrations and that mitochondrial proton gradients may be critical. The model offers an alternative explanation to variations of Faraday's Law and the Boltzmann constant that have been used to dismiss biological effects from weak magnetic fields.
Unknown authors · 2006
Researchers conducted a cross-sectional study of 780 children aged 0-12 years in two areas of Ismailia, Egypt. The exposed group comprised 390 children living within 50 meters of high voltage power lines, and the control group comprised 390 children from another area. Standard anthropometric measurements and hand X-rays for bone maturation were performed. Exposed children showed significantly reduced head and chest circumferences and height at all ages, and a significant delay in carpal bone ossification.
Unknown authors · 2006
Initial reports indicated that exposure of chicken eggs during embryonic development to power-line electric fields of 50 and 60 Hz at 10 V/m in air could cause the brain tissues of the hatched chickens to respond differently in a particular test. More recently, an anecdotal report of human sensitivity to EMF has appeared that shows a health-related influence of prior exposure history to particular power-line frequencies in chemically sensitized individuals. These reports open the question of whether the ambient electromagnetic environment can leave an imprint on developing organisms and if such imprint changes have the potential for health consequences.
Unknown authors · 2006
Takebayashi T et al. · 2006
Regular mobile phone use showed no significant increase in risk, with an odds ratio of 0.73 (95% CI 0.43 to 1.23). No increase in risk was observed for cumulative years of use or cumulative call time.
