Strasák L, Bártová E, Krejci J, Fojt L, Vetterl V. · 2009
Researchers exposed female and male laboratory mice for 4 days to a 50 Hz magnetic field at 2 mT inside a cylindrical coil. After exposure, levels of the proteins c-Jun and c-Fos in different parts of the brain were measured using Western-blot techniques. The expression of c-Jun decreased after magnetic field exposure, while c-Fos expression was not affected, and neither result depended on the sex of the mice.
Di Loreto S et al. · 2009
Researchers investigated the effects of exposures to two different 50 Hz sinusoidal ELF magnetic field intensities, 0.1 and 1 mT, on maturing rat cortical neurons. Exposure positively affected cell viability and reduced apoptotic death, with no significant effects on the main antioxidative defences. Linear regression analysis suggested a positive correlation between reduced glutathione and ROS levels in 1 mT magnetic-field-exposed cells. The researchers also observed brain-derived neurotrophic factor over-expression and interleukin 1β-dependent regulation of pro-survival signaling pathways following exposure.
Coşkun S, Balabanli B, Canseven A, Seyhan N. · 2009
Researchers exposed adult guinea pigs to a continuous and intermittent 50 Hz, 1.5 mT magnetic field for 4 hours per day for 4 days. Intermittent magnetic field exposure was effective on plasma lipid peroxidation, while continuous magnetic field exposure was effective on plasma MPO activity and NO levels. Augmentation of lipid peroxidation was observed in liver tissue under both intermittent and continuous magnetic field exposures.
Sirav B, Seyhan N · 2009
Researchers investigated the effects of 900 and 1,800 MHz continuous-wave radio frequency radiation on blood-brain barrier permeability in rats. Twenty minutes of exposure at both frequencies increased blood-brain barrier permeability in male rats, while female rats showed no change. The researchers noted that the scientific evidence on radio frequency radiation safety or harm remains inconclusive.
López-Martín E et al. · 2009
Researchers studied whether pulse-modulated GSM radiation had different effects on brain activity than an unmodulated signal of the same wavelength, and examined c-Fos expression in seizure-related brain circuits. Rats made seizure-prone with picrotoxin and then exposed to GSM radiation showed differences in clinical and EEG signs and in c-Fos expression compared with picrotoxin-treated rats exposed to unmodulated radiation. The most marked effects of GSM radiation on c-Fos expression in picrotoxin-treated rats were observed in limbic structures, olfactory cortex areas, subcortical areas, the dentate gyrus, and the central lateral nucleus of the thalamic intralaminar nucleus group. Neither radiation treatment caused tissue heating, so the researchers ruled out thermal effects.
Del Vecchio G et al. · 2009
Dasdag S, Akdag MZ, Ulukaya E, Uzunlar AK, Ocak AR · 2009
The study used 31 Wistar Albino adult male rats, with the exposed group having their heads placed in a carousel and exposed to 900 MHz microwave radiation for 2 hours per day, 7 days a week, for 10 months. The apoptosis score in exposed rats was significantly lower than in both the sham group and the cage control group. Total antioxidant capacity and catalase were higher in the exposed group than in the sham group, while the oxidative stress index showed no significant difference between those groups. The protein p53 was not significantly changed by the exposure.
Bas O, Odaci E, Kaplan S, Acer N, Ucok K, Colakoglu S · 2009
Researchers investigated the number of pyramidal cells in the hippocampus of 16-week-old female rats following postnatal exposure to 900 MHz EMF. Rats in the EMF group were exposed to 900 MHz EMF for 1 hour per day for 28 days, with a SAR ranging from 0.016 (whole body) to 2 W/kg (locally in the head). Postnatal EMF exposure caused a significant decrease of the pyramidal cell number in the CA, and cell loss was also visible at qualitative observation.
Luukkonen J et al. · 2009
Researchers exposed human SH-SY5Y neuroblastoma cells to 872 MHz radiofrequency radiation at 5 W/kg for 1 hour, combined with menadione, a chemical that induces intracellular ROS production and DNA damage. Continuous-wave RF radiation increased DNA breakage compared to cells exposed only to menadione, and ROS levels were higher at 30 and 60 minutes after exposure ended. No effects of the GSM signal were seen on either ROS production or DNA damage.
Gajski G, Garaj-Vrhovac V. · 2009
Researchers investigated whether bee venom could protect against DNA damage caused by 915-MHz microwave radiation in Wistar rat lymphocytes. Whole blood lymphocytes were treated with 1 μg/mL bee venom before irradiation, and comet assays were used to assess basal and oxidative DNA damage. Bee venom showed a decrease in DNA damage compared with irradiated samples, and was found to have a radioprotective effect against both basal and oxidative DNA damage.
Del Vecchio G et al. · 2009
Researchers studied the effects of radiofrequency electromagnetic field exposure on neuronal maturation using two in vitro models: murine SN56 cholinergic cells and rat primary cortical neurons. Cells were exposed at 1 W/kg at 900 MHz GSM modulated, and neurite emission, outgrowth, and branching were examined at multiple time points. RF-EMF exposure reduced the number of neurites in both cell systems, and this reduction correlated with increased expression of beta-thymosin mRNA.
Unknown authors · 2008
Researchers exposed the human keratinocyte cell line HaCaT to 1 mT, 50 Hz ELF-EMF for different lengths of time and compared them with unexposed control cells. Cell growth and viability were evaluated by cell count and trypan blue exclusion. Significantly increased growth rates were observed after 48 hours of EMF exposure compared with control cells, while no difference in cell viabilities was detected. Gene expression and release of RANTES, MCP-1, MIP-1 alpha and IL-8 were significantly reduced after 72 hours of exposure. NF-kappaB levels became almost undetectable after only 1 hour of EMF exposure and were inversely correlated with cell density.
Unknown authors · 2008
Researchers exposed Escherichia coli ATCC 700926 to 50 Hz electromagnetic fields at 0.1, 0.5, and 1.0 mT and compared them with sham-exposed controls. Exposed and control samples had similar total and culturable counts. Exposed samples showed increased cell viability after 24 hours of re-incubation outside the solenoid. Exposure for 20–120 minutes caused significant morphological changes including coccoid cells and atypical lengthened forms. DNA fingerprinting showed no changes, while RNA-AFLP analysis revealed some differences at each field intensity.
Unknown authors · 2008
Researchers exposed mouse osteoblast-like MC3T3-E1 cells to ELF-EMF at 3 mT and 60 Hz and measured cellular collagen as a marker of differentiation. ELF-EMF exposure significantly increased collagen content in the cells. Inhibiting the p38 MAPK pathway with SB203580 suppressed the ELF-EMF-induced collagen increase, while inhibiting the PI3K pathway with LY294002 accelerated it. The ERK1/2 inhibitor PD98059 reduced collagen in all conditions but did not block the ELF-EMF effect.
Unknown authors · 2008
Researchers evaluated the hormetic effect of non-thermal repetitive electromagnetic field shock (50MHz/0.5W) on primary human T lymphocytes and fibroblast cell lines. REMFS extended the total number of population doublings of mouse fibroblasts and contributed to youthful morphology of cells near their replicative lifespan. REMFS also enhanced cellular defenses of human T cells as reflected in lower cell mortality when compared to non-treated T cells. Mechanistic analysis showed that REMFS increased HSF1 phosphorylation, enhanced HSF1-DNA binding, and improved Hsp70 expression relative to non-REMFS-treated cells.
Unknown authors · 2008
The review examines physical principles for assessing radiofrequency interactions with biological systems at exposures up to endogenous electric field levels. It finds possible demodulation at membrane barriers for frequencies up to 10 MHz but not at higher frequencies. Molecular vibrational modes are too overdamped by water for excitation below the far infrared. Two mechanisms may plausibly affect biology: radical-pair reaction shifts below approximately 150 MHz and dielectric and resistive heating at all frequencies.
Unknown authors · 2008
Researchers exposed V79 cells to 935 MHz continuous wave UHF radiation at 8.2 V/cm and 0.12 W/kg SAR for 1, 2, and 3 hours. Microtubule structure was assessed by immunocytochemistry and cell growth was measured by cell counts over five post-exposure days. Microtubule structure was clearly altered after 3 hours of exposure compared to controls (p<0.05). Cell growth was significantly decreased in cells exposed for 3 hours, measured three days after irradiation (p<0.05).
Unknown authors · 2008
Researchers exposed murine L929 fibroblasts to 872 MHz continuous wave or pulse modulated RF radiation at 5 W/kg. They measured ornithine decarboxylase activity after 1- and 24-hour exposures, proliferation during 48 hours after 24-hour exposure, and caspase-3 activity after 1-hour exposure. The cells responded to fresh medium and serum deprivation, but no consistent effects of RF radiation were found. One statistically significant difference in ODC activity (p=0.03) was observed but considered a chance finding due to multiple comparisons and lack of support from other data. The results did not support effects on the endpoints studied, and stressed or stimulated cells were not more sensitive than normal cells to RF radiation.
Valbonesi P et al. · 2008
Researchers used the human trophoblast cell line HTR-8/SVneo to evaluate HSP70 and HSC70 protein and gene expression and primary DNA damage after nonthermal exposure to pulse-modulated 1817 MHz GSM-217 Hz waves for one hour at a SAR of 2 W/kg. Heat shock significantly enhanced HSP70 expression but not HSC70 expression. Exposure to high-frequency EMFs did not change HSP70 or HSC70 protein or gene expression. Hydrogen peroxide caused a significant increase in DNA strand breaks, but EMF exposure did not. Overall, no evidence was found that the exposure induced a HSP70-mediated stress response or primary DNA damage.
Sanchez S et al. · 2008
Researchers investigated heat shock protein expression in hairless rat skin exposed to GSM-900 and GSM-1800 signals. They studied Hsc70, Hsp25, and Hsp70 using immunolabeling of epidermal skin slices. Single exposures were 2 hours at 0 and 5 W/kg; repeated exposures were 2 hours per day, 5 days per week for 12 weeks at 0, 2.5, and 5 W/kg. Neither single nor repeated exposures altered HSP expression regardless of GSM signal or SAR.
Prisco MG et al. · 2008
Moisescu MG, Leveque P, Bertrand JR, Kovacs E, Mir LM · 2008
Researchers designed a device for continuous microscopic observation of cells exposed to modulated EMF similar to mobile phone signals. The system allowed follow-up of cell progression into mitosis under controlled temperature and CO2 environment. Cells exposed to 900 MHz modulated EMF for 1 hour at 30 degrees C and 2.2 W/kg showed increased endocytosis rate but no alteration in mitosis progression or duration. The exposure system was validated by cell endocytosis measurements.
Lerchl A et al. · 2008
Researchers exposed adult male Djungarian hamsters to RF-EMF at 383, 900, and 1800 MHz for 60 days at 80 mW/kg. Pineal and serum melatonin levels and organ weights were not affected in any experiment. Body weight increased transiently up to 4% at 383 MHz, increased up to 6% non-transiently at 900 MHz, and was unchanged at 1800 MHz.
Lee JJ et al. · 2008
NIH3T3 mouse fibroblasts were exposed to 849 MHz RF radiation at average SAR values of 2 or 10 W/kg for either 1 hour or 1 hour per day for 3 days. Cellular invasion and migration were assessed using in vitro Matrigel invasion and Transwell migration assays. Cell cycle distribution was analyzed at 24 and 48 hours after exposure by flow cytometry. The study found no detectable effects on cell cycle distribution, cellular migration, or invasion at the tested SAR values.
Huang TQ et al. · 2008
Researchers exposed HEI-OC1 immortalized mouse auditory hair cells to 1763 MHz RF at 20 W/kg SAR in a CDMA chamber for 24 and 48 hours. They assessed cell cycle, DNA damage, heat shock protein expression, MAPK phosphorylation, and gene expression, finding no changes in cell cycle, DNA damage, HSP expression, or MAPK phosphorylation. Microarray analysis showed only 29 genes (0.09% of total) changed more than 1.5-fold after exposure.
