Ye J, Yao K, Lu D, Wu R, Jiang H. · 2001
Researchers exposed one eye of each rabbit to 5 mW/cm2 or 10 mW/cm2 microwave radiation for 3 hours, using the contralateral eye as a control. They used Annexin V-propidium iodide two-color flow cytometry to detect early changes in lens epithelial cells. At 5 mW/cm2, many lens epithelial cells were in the initial phase of apoptosis. At 10 mW/cm2, a large number of cells became secondary necrotic cells and severe damage was observed.
Yang R, Chen J, Deng Z, Liu X, · 2001
Researchers cultured pig retinal ganglion cells in vitro, added vitamin E at different concentrations, and exposed them to 2450 MHz microwave radiation at 30 mW/cm² for 1 hour. Microwave exposure caused cell congregation, axon disappearance, mitochondria and endoplasmic reticulum swelling, and apoptosis. Vitamin E groups showed no obvious changes under optical microscope, though electron microscopy revealed light mitochondria swelling with intact cristae. The researchers concluded that microwave induced morphological damage and vitamin E reduced this damage to some extent.
Tattersall JE et al. · 2001
Radicheva N, Mileva K, Georgieva B, Kristev I · 2001
Researchers exposed isolated frog muscle fibers to continuous 2.45 GHz microwave radiation at 20 mW/cm² for one hour. Repetitive stimulation at 200 ms intervals evoked intracellular action potentials and twitch contractions. The twitch amplitude curve showed a drastic fall in the first 5 seconds followed by an increase and then a decrease. After microwave exposure, the changes in amplitude and time parameters that characterize fatigue were attenuated and delayed compared to controls. The authors concluded that microwaves have a specific non-thermal influence causing some resistance to fatigue.
Pashovkina MS, Akoev IG · 2001
Researchers exposed donor blood to pulse-modulated microwaves at 2375 MHz with intensities of 2 microW/cm2 and 8 microW/cm2, pulse modulation from 50 to 390 Hz, for 5 minutes. Aspartate aminotransferase activity was strongly dependent on both modulation frequency and microwave intensity. Maximum activity was found at 390 Hz and 8 microW/cm2, reaching about six times the control level.
Pashovkina MS, Akoev IG · 2001
Researchers exposed samples to pulse-modulated electromagnetic radiation at 2375 MHz with intensities of 0.8, 8.0, and 40.0 microW/cm2, modulation range 30-310 Hz, for 1-3 minutes. They observed a change in alkaline phosphotase activity in vitro.
Palfia Z, Somosy Z, Rez G · 2001
Researchers evaluated murine jejunal epithelial tight junctions after whole-body X-ray and microwave exposure using freeze fracture replicas. X-ray treatment at 4 Gy caused partial dearrangement of the ZO strand network that only partially regenerated by 24 hours. Microwave treatment at 16 Hz-modulated 2.45 GHz and 1 mW/cm2 for 1 hour did not cause dearrangement but increased integration of the tight junctional structure. The microwave effect agreed with an increase in cytochemically detectable ZO-bound calcium.
Mausset A, de Seze R, Montpeyroux F, Privat A · 2001
Researchers injected rats with gamma-vinyl-GABA to increase GABA levels and then used immunohistochemistry and image analysis to measure cerebellar GABA content. They exposed rats to 900 MHz pulsed radiofrequency at 4 W/kg SAR and continuous waves at 32 W/kg SAR. Pulsed exposure selectively reduced the stained processes area in the Purkinje cell layer, while continuous exposure decreased optical density in all three cell layers. The authors noted that it is unknown whether these effects are partly due to local tissue heating.
Lushnikov et al. · 2001
Researchers exposed healthy male NMRI mice to 42.0 GHz electromagnetic radiation at an energy flux density of 0.15 mW/cm2 under several different exposure regimes. After repeated exposures for 20 days before immunization, thymic cellularity was reduced by 17.5% and spleen cellularity by 14.5%, both statistically significant. The humoral immune response itself did not change significantly under any of the exposure regimes tested.
S. Kwee, P. Raskmark & S. Velizarov · 2001
Researchers exposed transformed human epithelial amnion (AMA) cells to a microwave field simulating the GSM signal at 960 MHz for 20 minutes. The field generated a specific absorption rate (SAR) of 2.1 mW.kg−1 in the cells, and exposures were carried out at temperatures of 35, 37, and 40 ± 0.1°C. Higher amounts of Hsp-70 were found in exposed cells at 35 and 37°C compared with sham-exposed cells, while Hsp-27 showed no significant response. The researchers considered these effects athermal because the field strength was much lower than the safety standard for absence of heat generation by microwave fields.
Cranfield CG, Wood AW, Anderson V, Menezes KG. · 2001
Researchers tested whether simulated GSM mobile phone signals at 915 MHz and 2 W kg(-1) influence calcium concentration or calcium signalling patterns in a human lymphocyte cell line. No significant changes were found in the regression slope of calcium fluorescence, mean calcium concentration, number of calcium spikes, or mean height of those spikes. A significant alteration in average frequency from Fourier spectra was found in one category only: pulsed wave exposure of activated cells.
Boscol P et al. · 2001
The study investigated the immune systems of 19 women with a mean age of 35 years who had been exposed to electromagnetic fields from radiotelevision broadcasting stations in their residential area for at least 2 years, with a mean exposure duration of 13 years. The exposed group had mean field levels of 4.3 plus or minus 1.4 V/m in the range 500 KHz to 3 GHz, while the control group had nearby residential exposure of less than 1.8 V/m. The exposed women showed statistically significant reductions in several immune cell types and lower in vitro production of IL-2 and interferon-gamma by peripheral blood mononuclear cells. The researchers concluded that high frequency electromagnetic fields reduce cytotoxic activity in the peripheral blood of women without a dose-response effect.
Simkó M, Droste S, Kriehuber R, Weiss DG · 2001
Researchers examined the effects of 50 Hz electromagnetic fields on phagocytosis and free radical production in mouse bone marrow-derived macrophages exposed in vitro to magnetic field densities of 0.5 to 1.5 mT. Short-time exposure of 45 minutes resulted in a significantly increased phagocytic uptake of 36.3% plus or minus 15.1%, as measured by the internalization rate of latex beads. A significant increase in superoxide production was also detected after exposure to electromagnetic fields. Because co-exposure to electromagnetic fields and TPA showed no additive increase in bead uptake, researchers concluded that the electromagnetic fields-induced stimulation does not involve the protein kinase C signal transduction pathway.
Jajte J, Zmyślony M, Palus J, Dziubałtowska E, Rajkowska E. · 2001
Researchers used the alkaline comet assay to assess DNA damage in rat peripheral blood lymphocytes exposed in vitro to iron ions and a 50 Hz magnetic field. Cell samples were incubated for 3 hours in Helmholtz coils at 7 mT 50 Hz, and some were treated with ferrous chloride at 10 μg/ml during that exposure. A significant increase in cells with DNA damage was found only after simultaneous exposure to ferrous chloride and the 7 mT 50 Hz magnetic field, compared to control samples or those incubated with ferrous chloride alone. When cells were treated with melatonin before that combined exposure, the number of damaged cells was significantly reduced, with the reduction reaching about 50% at 0.5 mM and about 100% at 1.0 mM.
Sykes PJ, McCallum BD, Bangay MJ, Hooker AM, Morley AA. · 2001
Researchers studied the effect of pulsed 900 MHz radiofrequency radiation at 4 W/kg on somatic intrachromosomal recombination in the spleen of pKZ1 mice. Mice were exposed daily for 30 minutes to 900 MHz fields for 1, 5, or 25 days, and spleen sections were screened for DNA inversion events three days after the last exposure. There was no significant difference between control and treated groups in the 1- and 5-day exposure groups, but a significant reduction in inversions was found in the 25-day group.
Trosic I · 2001
Researchers exposed rats to 2450 MHz microwaves at power densities of 5 to 15 mW/cm², in sessions of two hours each, with groups receiving 2, 8, 13, or 22 treatments. Multinucleated cells significantly increased (p<0.01) in treated animals, with the elevation being time- and dose-dependent. Cell viability did not significantly change in the irradiated animal group compared with the control group.
Unknown authors · 2000
The researchers studied the effect of extremely low frequency electromagnetic fields combined with mild heat shock on reporter gene expression in two transgenic strains of Caenorhabditis elegans. Reporter gene expression was measured by scoring animals with induced beta-galactosidase activity after staining in toto or by biochemical quantitation of enzyme activity. They defined experimental conditions where electromagnetic fields strongly enhanced the expression of the reporter gene.
Unknown authors · 2000
Researchers attempted to replicate earlier findings by testing whether a 1.5-G 50-Hz magnetic field alters intracellular free calcium in Jurkat lymphocyte T-cells. Cells were randomly assigned to magnetic field, sham field, or no-field exposures for 8 minutes each in a blinded design. The percentage of cells showing calcium transients was 16.5% for magnetic field, 14.6% for sham, and 14.2% for no field, with no statistically significant differences among them. The authors concluded that their methods did not identify responsive cells, if such cells exist, and that the results do not rule out a magnetic field effect on calcium.
Unknown authors · 2000
Researchers examined the effect of 50 mT, 60 Hz ELFMF on heat-induced HSP-70 expression in HL60RG cells. Exposure to 50 mT ELFMF alone did not increase HSP-70 production. Combined exposure to 50 mT ELFMF and mild heat at 40°C and 42°C suppressed heat-induced HSP-70 expression. This suppression required simultaneous exposure for more than 5 hours. Lower magnetic densities of 5 mT and 0.5 mT did not suppress HSP-70.
Maes A, Collier M, Verschaeve L · 2000
Researchers exposed human lymphocytes to 455.7 MHz microwaves from a car phone at a specific absorption rate of approximately 6.5 W/kg. No statistically significant difference was found between microwave-exposed and unexposed control samples for chromosome aberration or sister chromatid exchange frequency. When microwave exposure was followed by MMC treatment, some differences appeared between combined and MMC-only treatments, but results were inconsistent. Combined exposure with X-rays showed no indication of synergistic action between RF fields and X-rays. The authors concluded that the data do not support the hypothesis that RF fields act synergistically with chemical or physical mutagens.
Lu ST et al. · 2000
Researchers studied retinal effects of 1.25 GHz high peak power microwaves in Rhesus monkeys. Preexposure and postexposure fundus pictures and angiograms were all within normal limits. Cone photoreceptor response to light flash was enhanced at 8.4 and 20.2 W/kg R-SAR but not at 4.3 W/kg R-SAR. Enhanced glycogen storage in photoreceptors was observed in sham, 8.4, and 20.2 W/kg groups but not in the 4.3 W/kg group. No degenerative changes or ERG depression were observed, and retinal injury was considered very unlikely at 4 W/kg.
Vijayalaxmi, Leal BZ, Szilagyi M, Prihoda TJ, Meltz ML · 2000
Human peripheral blood samples from three volunteers were exposed to pulsed-wave 2450 MHz radiofrequency radiation for 2 hours. The exposure used a net forward power of 21 W with an average power density of 5 mW/cm2 and a mean specific absorption rate of 2.135 W/kg. DNA damage was measured using the alkaline comet assay immediately and 4 hours after exposure. No significant differences were found in comet tail length, fluorescence intensity, or tail moment between RF-exposed and sham-exposed lymphocytes at either time point. The response of lymphocytes exposed to ionizing radiation was significantly different from RF-radiation- and sham-exposed cells.
Yoshikawa T et al. · 2000
Sidorenko A, Tsaryuk V · 2000
Researchers studied the effects of microwave radiation and strychnine on cerebral biopotentials in narcotized rats. Strychnine and microwave radiation produced changes in spectral parameters of electrocorticogram, correlation dimension, and Kolmogorov entropy opposite to those induced by urethane.
Schirmacher A et al. · 2000
