Unknown authors · 2006
Researchers studied the effect of 50 Hz electromagnetic field on the thyroid gland using light and transmission electron microscopes. Two-month-old male rats were exposed to an EMF of 100-300 μT and 54-160 V m-1 for 4 h a day, 5 days a week for 1 month. The EMF group showed a predominance of microfollicles with less colloid content and dilated blood capillaries. Stereological counting revealed a statistically significant increase in the volume density of follicular epithelium, interfollicular tissue, blood capillaries, and the thyroid activation index, while the volume density of colloid significantly decreased.
Takashima Y et al. · 2006
Researchers exposed cells to radio frequency electromagnetic fields at 2.45 GHz to examine cell growth, survival, and cell cycle distribution across a wide range of specific absorption rates. When cells were exposed to a continuous RF field at SARs from 0.05 to 100 W/kg for 2 h, cellular growth rate, survival, and cell cycle distribution were not affected. At 200 W/kg, the cell growth rate was suppressed and cell survival decreased, and the temperature of the medium rose to 44.1 degrees C. The researchers suggested that the proliferation disorder is caused by the thermal effect.
Unknown authors · 2006
The study used a crossover design with healthy premenopausal women exposed to a 60-Hz magnetic field of 5 to 10 mG greater than ambient levels for 5 consecutive nights during the early to midluteal phase of the menstrual cycle. Magnetic field exposure was associated with decreased 6-sulfatoxymelatonin levels, but no changes in reproductive hormone levels were observed. Participants using prescription medications and anovulatory participants had more pronounced decreases in 6-sulfatoxymelatonin levels with magnetic field exposure.
Paulraj R, Behari J · 2006
The control group was sham irradiated. The study revealed a statistically significant decrease in PKC activity in the hippocampus compared to the rest of the brain and controls. Electron microscopy showed an increase in glial cell population in the exposed group.
Unknown authors · 2006
Researchers exposed female mice to 50 Hz, 1.2 mT electromagnetic fields for 8 hours per day throughout pregnancy. Exposed dams gained weight more slowly (29.0% vs 47.8%) and had a lower producing rate (60% of controls), with miscarriages, fetal loss, and malformed fetuses observed. The average number of offspring per mouse decreased (11 ± 1.6 vs 7 ± 2.0), and prenatally exposed offspring showed slower weight gain in the first two weeks and delayed eye opening and tooth eruption.
Unknown authors · 2006
Researchers investigated effects of electromagnetic fields on DNA damage in preimplantation mouse embryos using gammaH2AX foci formation as an indicator. EMFs decreased the cleavage rate of preimplantation mouse embryos. The decreasing effect was related to DNA damage shown by gammaH2AX foci formation. Noise magnetic fields or wortmannin inhibited the EMF-induced gammaH2AX foci formation. EMFs could activate the DNA damage-repair mechanism by recruiting Rad50 to damaged DNA sites.
Vijayalaxmi · 2006
Researchers exposed peripheral blood lymphocytes from healthy volunteers to 2.45 GHz or 8.2 GHz pulsed-wave RF radiation for 2 hours. They measured chromosomal aberrations and micronuclei to assess cytogenetic damage. The RF-exposed lymphocytes showed no significant increase in damage compared to sham-exposed lymphocytes. Gamma-irradiated positive control cells showed significantly more damage than both RF-exposed and sham-exposed cells.
Unknown authors · 2006
Researchers used the micronucleus test with CREST antibody staining to assess clastogenic and aneugenic effects of a 50 Hz, 650 muT magnetic field. Newborn mice were exposed during the entire 21-day intra-uterine period, and adult mice were exposed for the same duration. Newborn mice showed a significant increase in micronuclei frequencies, with most induced micronuclei being CREST-negative chromosome fragments. ELF exposure caused a two-fold increase in CREST-negative micronuclei and a four-fold increase in CREST-positive micronuclei in newborn mice. No significant effect was observed in exposed adult mice.
Unknown authors · 2006
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
This theoretical study by Dr. Michael Persinger proposes that extremely weak magnetic fields in the nanoTesla range (35-70 nT at 7 Hz frequency) could affect melatonin molecules and potentially treat conditions like multiple sclerosis. The hypothesis suggests these fields work through a resonance mechanism that depends on melatonin concentration levels in specific body tissues.
Unknown authors · 2006
This theoretical study by researcher Michael Persinger proposes a mechanism for how extremely weak magnetic fields (in the nanoTesla range) could affect melatonin levels and potentially treat neurological conditions like multiple sclerosis. The hypothesis suggests that 7 Hz magnetic fields at specific intensities (35-70 nanoTesla) could resonate with melatonin molecules to produce therapeutic effects. This challenges conventional thinking that such weak fields are too small to have biological impact.
Espinosa JM, Liberti M, Lagroye I, Veyret B. · 2006
Researchers studied the binding properties of the serotonin 5-HT1B receptor in rat brain membranes under exposure to AC and DC magnetic fields. One-hour exposures at 1.1 mT at 50 Hz caused statistically significant increases in both the K(D) and B(max) binding parameters, from 1.74 to 4.51 nM and from 1428 to 2137 CPM, respectively. DC fields had a lesser effect compared to AC fields at low values of K(Dsham), but decreased the affinity at higher values of K(Dsham). The researchers described these findings as one of the few documented pieces of evidence for cell-free effects of DC and extremely low frequency AC magnetic fields in the mT range.
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
This 2006 review examined whether EMF exposure during embryonic development can create lasting physiological changes. Studies found that chicken embryos exposed to common 50-60 Hz power line frequencies (at levels found in human environments) showed altered brain responses after hatching. The research raises concerns about whether EMF exposure during critical developmental periods leaves permanent biological imprints.
Unknown authors · 2006
Researchers investigated the effects of pulsed electric fields at 50 Hz on DNA of human lymphocytes using the comet assay. A significant amount of DNA damage was observed after exposure compared to controls. After 2 hours incubation at 37°C, a proportion of the damage was repaired. Hydrogen peroxide and gamma-irradiation increased the damage to lymphocytes exposed to pulsed electric fields according to the dose used, and the amount of repair was proportional to the damage.
Trosic I, Busljeta I. · 2006
Researchers exposed rats to 2.45 GHz microwave radiation at a whole-body SAR of 1.25+/-0.36 W/kg for 2 hours per day, 7 days a week. Bone marrow polychromatic erythrocytes increased on days 8 and 15, and peripheral blood polychromatic erythrocytes increased on days 2 and 8. Bone marrow micronucleated PCE frequency increased on day 15, and peripheral blood micronucleated PCEs increased on day 8, but all values declined nearly to control levels by the end of the experiment.
Unknown authors · 2006
Two experiments were carried out to assess the effects of electric and magnetic fields on blood thyroxine in dairy cattle. In experiment 2, 16 nonlactating, nonpregnant, multiparous Holsteins were exposed to the same EMF with periods corresponding to one estrous cycle and blood samples were collected every other day, and the effect of period (P = .0009) and the treatment by days interaction (P = .0003) were statistically significant.
Sun LX, Yao K, Jiang H, He JL, Lu DQ, Wang KJ, Li HW · 2006
Researchers exposed cultured human lens epithelial cells to 217 Hz modulated microwave radiation at four SAR levels for 2 hours. DNA single strand breaks were measured using the comet assay immediately after irradiation and at 30 and 60 minutes afterward. At the highest dose, significant DNA damage remained one hour after irradiation and cell proliferation was significantly decreased.
Wang LL, Chen GD, Lu DQ, Chiang H, Xu ZP. · 2006
Researchers intermittently exposed MCF-7 cells to GSM 1800 MHz RF EMF modulated by 217 Hz for 24 hours at SARs of 2.0 W/kg or 3.5 W/kg. A small number of differentially expressed genes were found after exposure. Reproducible analysis yielded no genes at 2.0 W/kg and five up-regulated genes at 3.5 W/kg. The five genes identified at 3.5 W/kg could not be confirmed by RT-PCR. The authors concluded that the study did not provide clear evidence of distinct gene expression changes under the experimental conditions.
Aksen F, Akdag MZ, Ketani A, Yokus B, Kaya A, Dasdag S. · 2006
Jelenković A et al. · 2006
Researchers exposed adult male Wistar rats to a 50 Hz, 0.5 mT extremely low-frequency magnetic field for 7 days, while control rats were sham-exposed. Superoxide dismutase activities and production of superoxide radicals, lipid peroxidation, and nitric oxide were examined in the frontal cortex, striatum, basal forebrain, hippocampus, brainstem, and cerebellum. Superoxide radicals were significantly increased in all regions examined, and lipid peroxidation was significantly increased in the basal forebrain and frontal cortex. The researchers indicated that the 7-day exposure can be harmful to the brain, especially to the basal forebrain and frontal cortex due to development of lipid peroxidation.
Reale M et al. · 2006
Researchers investigated whether overnight exposure to a 1 mT, 50-Hz sinusoidal electromagnetic field affects the expression of iNOS and MCP-1 in human monocytes. EMF exposure affected iNOS and MCP-1 expression in cultured human mononuclear cells at both the mRNA level and the protein level. iNOS was down-regulated while MCP-1 was up-regulated.
Bediz CS, Baltaci AK, Mogulkoc R, Oztekin E. · 2006
Twenty-four male Sprague-Dawley rats were randomly allocated to three groups: control, EMF-exposed (50 Hz, 5 minutes every other day for 6 months), and EMF-exposed with zinc sulfate (3 mg/kg/day intraperitoneally). Researchers measured plasma zinc and TBARS, and GSH in erythrocytes; TBARS and GSH were also determined in brain tissues. TBARS levels in plasma and brain were higher in EMF-exposed rats than controls, and lower in zinc-supplemented rats than EMF-exposed rats. GSH levels decreased in brain and erythrocytes of EMF-exposed rats and were highest in zinc-supplemented rats. Plasma zinc was lower in EMF-exposed rats than controls and highest in zinc-supplemented rats.
Calota V, Dragoiu S, Meghea A, Giurginca M · 2006
Researchers investigated the decrease of luminol chemiluminescence upon exposure of human blood serum to 50 Hz electric fields. After 1 and 2 hours of in vitro exposure to 50 Hz electric fields of different intensities, the chemiluminescence of luminol decreased compared to controls. The authors indicate this reflects a field-induced decrease in free radical concentration.
