Baohong W et al. · 2007
Researchers exposed human lymphocytes to 1.8 GHz microwaves at a SAR of 3 W/kg, ultraviolet ray C (UVC), or both, then measured DNA damage using the comet assay. Microwave exposure alone did not produce significantly more DNA damage than the control group. When combined with UVC, microwave exposure was associated with reduced DNA damage at 1.5-hour incubation but increased DNA damage at 4-hour incubation, compared with UVC alone.
Todorović D, Kalauzi A, Prolić Z, Jović M, Mutavdzić D. · 2007
Researchers measured the influence of a static magnetic field at 2 mT on neuronal population activity in eight individuals of the endangered insect species Morimus funereus. Five minutes of exposure produced excitatory effects in 5 of 8 individuals and inhibitory effects in 3 of 8 individuals in the antennal lobe. When reversibility was analyzed, the induced effects were prevailingly irreversible: 7 of 8 for the neuronal population and 6 of 8 for the nearest neuron.
Shen JF, Chao YL, Du L. · 2007
Researchers used whole-cell patch-clamp experiments on acute dissociated rat trigeminal root ganglion neurons to study how static magnetic fields affect voltage-gated potassium channel currents. The study evaluated the effects of moderate-intensity static magnetic fields on two types of voltage-gated potassium channel currents, called IK,A and IK,V. A 125 mT static magnetic field altered the inactivation rate and velocity of both channel currents, while activation properties showed no significant change.
Del Giudice E et al. · 2007
Researchers tested whether low-frequency electromagnetic field exposure could affect amyloid-related processes in cultured cells. The study exposed H4 neuroglioma cells, which overexpress human mutant amyloid precursor protein, to a 3.1 mT 50 Hz electromagnetic field. Overnight exposure led to a significant increase in amyloid-beta peptide secretion, including the isoform Abeta 1-42, without affecting cell survival.
Zeni et al. · 2007
Researchers investigated whether 900 MHz RF radiation could induce reactive oxygen species in murine L929 fibrosarcoma cells, with or without co-exposure to MX, a potent environmental carcinogen produced during chlorination of drinking water. Both continuous-wave and GSM mobile phone signals were applied for 10 or 30 min at specific absorption rates of 0.3 and 1 W/kg. The study found no indication that RF-field exposure, alone or combined with MX, induced reactive oxygen species formation, while MX alone caused a statistically significant increase in reactive oxygen species for all the treatment durations investigated.
Tkalec M, Malarić K, Pevalek-Kozlina B. · 2007
Researchers exposed duckweed (Lemna minor) to radiofrequency electromagnetic fields at 400 and 900 MHz, at field strengths of 10, 23, 41, and 120 V m−1, for 2 hours, and also tested a longer 4-hour exposure and modulated fields. After exposure, the researchers measured lipid peroxidation, H2O2 content, antioxidative enzyme activities and isoenzyme patterns, and HSP70 expression. At 900 MHz, almost all exposure treatments significantly increased lipid peroxidation and H2O2 content, mostly decreased PPX activity, and did not affect CAT activity. No differences in isoenzyme patterns of antioxidative enzymes or HSP70 level were found between control and exposed plants at either frequency.
Sirmatel O, Sert C, Tümer C, Oztürk A, Bilgin M, Ziylan Z · 2007
Researchers measured nitric oxide production in 33 healthy young male volunteers aged 18 to 26 years old immediately after a 30-minute exposure to a 1.5 T magnetic field. A control group of 30 healthy male volunteers aged 19 to 26 years old was not exposed to the magnetic field, and their nitric oxide levels were also measured. Total nitrite concentration in post-exposure samples was found to be higher than in pre-exposure samples (P < .05).
Sirmatel O, Sert C, Sirmatel F, Selek S, Yokus B · 2007
Researchers investigated the effects of a 1.5 T static magnetic field, produced by an MRI apparatus, on oxidative stress markers in 33 male volunteers. Total antioxidant capacity showed a significant increase after exposure compared to before exposure (p < 0.05). Oxidative stress index and total oxidant status showed a significant decrease after exposure compared to before exposure (p < 0.01 for each). The researchers concluded that the 1.5 T static magnetic field produced a positive effect of decreasing oxidative stress in men following short-term exposure.
Sahebjamei H, Abdolmaleki P, Ghanati F · 2007
Researchers investigated the effects of static magnetic fields on antioxidant enzyme activities in suspension-cultured tobacco cells. Cells were exposed to static magnetic fields at 10 and 30 mT for 5 days, 5 hours each day, and compared with control cells. Superoxide dismutase activity increased with exposure, while catalase and ascorbate peroxidase activity decreased, and lipid peroxidation levels also increased.
Cheun BS, Yi SH, Baik KY, Lim JK, Yoo JS, Shin HW, Soh KS · 2007
Researchers studied biophoton emission from Madin-Darby canine kidney (MDCK) cells treated with hydrogen peroxide, with and without exposure to a 60 Hz AC magnetic field. Hydrogen peroxide increased biophoton emission from the cells, and the increase was dependent on the amount of hydrogen peroxide applied. When the 60 Hz AC magnetic field was applied, the decay of chemiluminescence intensity took a different path compared to cells not exposed to the field.
Akdag MZ, Bilgin MH, Dasdag S, Tumer C · 2007
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.
Ishay JS et al. · 2007
Researchers kept Oriental hornet workers in an Artificial Breeding Box and exposed them to an AC magnetic field of a magnitude of B = 50-70 mGauss, comparing the combs they built with those from a control group exposed only to the natural terrestrial magnetic field. Exposed hornets built combs with a 35-55% smaller number of cells and fewer eggs, many deformed and imperfectly hexagonal cells, and more delicate and slender comb stems.
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.
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.
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.
Whitehead TD, Moros EG, Brownstein BH, Roti Roti JL. · 2006
Researchers exposed cultured C3H 10T 1/2 cells to cell phone RF radiation at a specific absorption rate of 5 W/kg for 24 hours. Gene expression was measured using Affymetrix microarrays and compared to sham controls. The RF exposure did not produce more gene expression changes than expected by chance. In contrast, X-ray exposure at 0.68 Gy with a 4-hour recovery produced more changes than the sham comparison.
Whitehead TD, Moros EG, Brownstein BH, Roti Roti JL · 2006
Researchers performed in vitro experiments with C3H 10T(1/2) mouse cells to test whether FDMA or CDMA modulated RF radiation induces changes in gene expression. Cells were exposed to either modulation for 24 h at a specific absorption rate (SAR) of 5 W/ kg. Gene expression was evaluated using the Affymetrix U74Av2 GeneChip to detect changes in mRNA levels. As a positive control, cells were exposed to 0.68 Gy of X rays and gene expression was evaluated 4 h after exposure. For both CDMA and FDMA radiation, the number of probe sets with expression changes greater than 1.3-fold was less than or equal to the expected false positives, indicating no statistically significant effect on gene expression.
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.
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.
Tuschl H, Novak W, Molla-Djafari H. · 2006
The study assessed whether GSM-modulated RF fields have adverse effects on the functional competence of human immune cells. Exposure was performed at GSM Basic 1950 MHz with an SAR of 1 mW/g in an intermittent mode of 5 minutes on and 10 minutes off for 8 hours. Researchers evaluated intracellular cytokine production, immune-relevant gene activity, and cytotoxicity of lymphokine-activated killer cells using blood from at least 15 donors per parameter. No statistically significant effects of exposure were found.
Thorlin et al. · 2006
Researchers exposed cultured astroglial and microglial cells to 900 MHz microwave radiation at various SARs and durations. They measured markers including interleukin 6, tumor necrosis factor-alpha, glial fibrillary acidic protein, total protein, and ED-1. No significant differences were found for any parameter at any time or radiation characteristic. Total protein levels remained constant and cell morphology appeared unaffected. The study concluded no evidence for effects on damage-related factors in glial cells.
