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.
Yurekli AI et al. · 2006
Researchers used a gigahertz transverse electromagnetic (GTEM) cell to expose rats to electromagnetic fields at the GSM base transceiver station frequency of 945 MHz. The power density applied was 3.67 W/m2 (specific absorption rate = 11.3 mW/kg), which the researchers described as well below current exposure limits. MDA levels increased and GSH concentrations decreased significantly (p < 0.0001) under this exposure. There was also a less significant (p = 0.0190) increase in SOD (superoxide dismutase) activity under EM exposure.
Ozguner F, Bardak Y, Comlekci S. · 2006
Researchers compared how well melatonin and caffeic acid phenethyl ester (CAPE) protected rat retinas from oxidative stress caused by exposure to 900 MHz mobile-phone radiation. Melatonin and CAPE were administered daily for 60 days to the rats prior to their EMR exposure. Retinal levels of the oxidative stress markers NO and MDA increased in EMR-exposed rats, while both melatonin and CAPE caused a significant reduction in those levels. Antioxidant enzyme activities (SOD, GSH-Px, and CAT) decreased in EMR-exposed animals, but both treatments significantly increased those activities.
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.
Frahm J, Lantow M, Lupke M, Weiss DG, Simkó M · 2006
Researchers investigated whether extremely low frequency electromagnetic fields affect cellular functions and immunologic parameters of mouse macrophages. Magnetic field exposure led to a 1.6-fold increased uptake of latex beads in exposed cells compared to controls after 45 minutes. IL-1β formation increased significantly after 4 hours and reached a maximum 12.3-fold increase after 24 hours compared to controls. All tested flux densities significantly stimulated free radical formation, and no significant differences in micronucleus formation were found in exposed cells.
De Nicola M et al. · 2006
Researchers exposed U937 cells to static magnetic fields at 6 mT and found a strong increase of reactive oxygen species and a decrease of glutathione levels after 2 hours of exposure. Extremely-low-frequency magnetic fields also affected intracellular glutathione, starting from a threshold at 0.09 mT. ELF magnetic fields protected U937 from apoptosis, but this ability was limited to the ELF intensities able to alter redox equilibrium. When the cells' redox state was artificially altered, magnetic fields failed to affect apoptosis, suggesting a correct intracellular redox state is required for the antiapoptotic effect.
Aksen F, Akdag MZ, Ketani A, Yokus B, Kaya A, Dasdag S. · 2006
Nylund R, Leszczynski D. · 2006
Researchers examined in vitro cell response to mobile phone radiation using two variants of a human endothelial cell line: EA.hy926 and EA.hy926v1. Gene expression changes were examined using cDNA Expression Arrays and protein expression changes were examined using 2-DE and PDQuest software. Gene and protein expression were altered in both examined cell lines after one hour of exposure at an average specific absorption rate of 2.8 W/kg, but the same genes and proteins were differently affected in each line.
Zhang DY, Xu ZP, Chiang H, Lu DQ, Zeng QL. · 2006
Researchers studied the effects of GSM 1800 MHz radiofrequency electromagnetic fields on DNA damage in Chinese hamster lung cells. Cells were intermittently exposed to GSM 1800 MHz RF EMF at a SAR of 3.0 W/kg for either 1 hour or 24 hours, using a pattern of 5 minutes on and 10 minutes off. After 24 hours of exposure, the percentage of gammaH2AX foci positive cells was 37.9 +/- 8.6%, significantly higher than the sham-exposed group at 28.0 +/- 8.4%. The 1-hour exposure showed no significant difference from sham exposure.
Sun LX, Yao K, He JL, Lu DQ, Wang KJ, Li HW. · 2006
Cultured LECs were exposed to 217 Hz modulated 1.8 GHz microwave radiation at specific absorption rates of 0, 1, 2, 3, and 4 W/kg for 2 hours. DNA single strand breaks were detected with comet assay at 0, 30, 60, 120, and 240 minutes after irradiation. At 1 and 2 W/kg, the difference in DNA breaks between exposure and sham exposure groups was not significant at any detection time. At 3 and 4 W/kg, differences were significant immediately and 30 minutes after irradiation, with the difference disappearing after one hour in the 3 W/kg group but persisting in the 4 W/kg group.
Lixia S et al. · 2006
Researchers exposed human lens epithelial cells (hLEC) to a 1.8 GHz GSM radiofrequency field at SARs of 1, 2, and 3 W/kg for 2 hours and then measured DNA damage, Hsp70 expression, and cell proliferation. DNA breaks at 1 and 2 W/kg were not significantly different from controls at any time point, while the 3 W/kg dose showed significantly increased DNA damage only at 0 and 30 minutes after exposure. Hsp70 protein expression was significantly increased at 2 and 3 W/kg, but Hsp70 mRNA expression did not change in any group, and cell proliferation was unaffected at all doses.
Unknown authors · 2005
Three talks covered cellular, animal, and epidemiological studies of static magnetic fields. The overall conclusion was that scientific evidence is weak with large gaps due to poor study quality or lack of research. Rapid technological development is increasing human exposure to stronger static magnetic fields. Knowledge about health effects lags far behind this technological development.
Unknown authors · 2005
Researchers exposed insulin solution to a pulsed electric field of 0.7 V/m at 50 Hz for 20 minutes and then added it to human hepatocyte cultures. They investigated insulin signaling events including ligand-receptor binding, tyrosine phosphorylation, gene transcription, and cell proliferation using multiple methods. PEF exposure caused a conformational change in insulin, reduced its receptor binding capacity to 87% of control, and decreased intracellular tyrosine phosphorylation by 11%. The expression of 55 out of 12000 genes was altered, including increased expression of human tyrosine phosphatase and a small GTP-binding protein.
Unknown authors · 2005
The study used molecular dynamics simulations to examine insulin chain-B under static and oscillating electric fields ranging from 10(7) to 10(9) V/m. Both field types affected the protein's normal behavior, with oscillating fields being more disruptive to structure than static fields of similar strength. Static fields stabilized the secondary structure but restricted the inherent flexibility required for insulin's biological activity.
Swanson J et al et al. · 2005
Whitehead TD et al. · 2005
The study aimed to confirm a previous report that CDMA and FDMA radiation increased Fos levels as cells entered plateau phase. Fos mRNA levels were not significantly different from sham exposure at either SAR level for any signal modulation. Therefore, the earlier results could not be confirmed.
Wang J et al. · 2005
Researchers exposed mouse C3H10T1/2 cells to 2450 MHz HFEMF at SARs of 5 to 200 W/kg for 2 hours, with or without methylcholanthrene (MC) and the tumor promoter TPA. Transformed foci of Type II and Type III were counted as the endpoint. No significant differences were observed in malignant transformation frequency between controls and HFEMF with or without TPA. Transformation frequency increased for HFEMF at SAR above 100 W/kg when combined with MC or MC plus TPA, while heat exposure did not increase transformation.
Ozguner M et al. · 2005
Twenty adult male Sprague-Dawley rats were randomized into a control group and an EMF group exposed to 900 MHz EMF for 30 minutes per day, 5 days a week for 4 weeks. Testicular weight, biopsy score, and interstitial tissue percentage did not differ significantly between groups. Seminiferous tubule diameter and germinal epithelium height were significantly decreased in the EMF group. Serum testosterone was significantly lower in the EMF group, while LH and FSH did not change significantly.
Miyakoshi J et al. · 2005
Researchers exposed human glioma MO54 cells to a continuous wave 1950 MHz RF field at SARs of 1, 2, and 10 W/kg for up to 2 hours. Cell growth was assessed by counting cell numbers up to 4 days after exposure. RF exposure at 2 and 10 W/kg did not affect the growth of MO54 cells. However, exposure at 10 W/kg for 1 and 2 hours significantly decreased the protein level of phosphorylated Hsp27 at serine 78.
Lim HB, Cook GG, Barker AT, Coulton LA. · 2005
Researchers exposed human peripheral blood to 900 MHz fields at specific absorption rates of 0.4, 2.0, and 3.6 W/kg for durations of 20 minutes, 1 hour, and 4 hours. Heat stress at 42 degrees Celsius increased the number of cells expressing HSP70 and HSP27 in a time-dependent manner. No statistically significant difference in stress protein expression was detected after RF-field exposure.
Lee JS, Huang TQ, Lee JJ, Pack JK, Jang JJ, Seo JS. · 2005
Researchers exposed eight-week-old hsp70.1-deficient mice twice daily for 45 minutes with a 15-minute interval, five days a week for ten weeks at a whole-body average specific absorption rate of 0.4 W/Kg for both 849 MHz and 1763 MHz fields. They examined major tissues histopathologically, assessed cell proliferative activity immunocytochemically, measured apoptosis with a TUNEL assay, and evaluated heat shock protein expression and stress-activated kinase phosphorylation by western blot. No histopathological differences were found between sham- and RF-exposed mice, and there was no evidence of increased proliferative or apoptotic activity. Levels of HSP90, HSP70, and HSP25 showed no obvious changes, and RF exposure did not affect phosphorylation of ERK1/2, JNK1/2, or p38 MAPK.
Laszlo et al. · 2005
Researchers measured heat-shock factor DNA-binding activity in hamster, mouse, and human cells after exposure to FDMA- or CDMA-modulated microwaves at low or high SARs. The assay could detect a 10% increase in HSF activation from a 1°C temperature rise. No increase in HSF DNA-binding ability was detected from any exposure tested. The results do not support activation of the stress response by mobile communication microwaves.
Koyu A, Cesur G, Ozguner F, Akdogan M, Mollaoglu H, Ozen S. · 2005
The study examined effects of 900 MHz EMF on thyroid hormones in adult male Sprague-Dawley rats. Thirty rats were divided into control, EMF-exposed, and sham-exposed groups of ten each. Exposed rats received 30 minutes of EMF per day, five days a week, for four weeks. TSH and T3-T4 levels were significantly lower in the EMF group than in the sham group (p<0.01). No significant differences were found between control and sham groups (p>0.05).
Komatsubara Y et al. · 2005
Researchers exposed murine m5S cells to 2.45 GHz high-frequency electromagnetic fields for 2 hours at SARs of 5, 10, 20, 50, and 100 W/kg continuous wave and at a mean SAR of 100 W/kg pulse wave with a maximum of 900 W/kg. The effects were compared with sham-exposed controls and with mitomycin C and X-ray treatments as positive controls. No significant differences in chromosomal aberrations were observed between HFEMF-exposed cells and sham controls, while positive controls increased chromatid-type and chromosome-type aberrations.
Huang TQ, Lee JS, Kim TH, Pack JK, Jang JJ, Seo JS. · 2005
The study used 80 male ICR mice initiated with DMBA and then exposed to 849 MHz or 1,763 MHz RF radiation at 0.4 W/kg SAR for 19 weeks. No skin tumors were observed in the sham or RF-exposed groups, while the TPA positive control group had a 95% tumor incidence. Pathological examination and PCNA staining showed no differences between sham and RF-exposed groups, and cyclin D1 and c-fos expression was only detected in TPA-induced tumors. The researchers concluded that RF radiation does not act as a tumor promoter for skin tumors in this model.
