Gao XF,Pei LP, Chen CH, Yang XS, Zhang GB, Deng ZH, Yu ZP. · 2009
Researchers exposed rats to whole-body microwave irradiation at 90 and 5 W/cm² for 20 minutes and measured changes in HSP70 in the hippocampus. Both mRNA and protein expression of HSP70 in the rat hippocampus increased after the exposures. Anal temperature and SAR values also increased significantly, and these changes were positively correlated with power and irradiation time.
Augner C, Florian M, Pauser G, Oberfeld G, Hacker GW. · 2009
Researchers examined the effects of short-term GSM base station radiofrequency electromagnetic field exposure on psychological symptoms including good mood, alertness, and calmness, as measured by a standardized well-being questionnaire. Fifty-seven participants were randomly assigned to one of three different exposure scenarios, each involving five 50-min exposure sessions. Participants in the high and medium exposure scenarios were significantly calmer than those in the low-exposure scenario (P = 0.042), though no significant differences were found for good mood or alertness. The researchers concluded that short-term exposure to GSM base station signals may have an impact on well-being by reducing psychological arousal.
Amara S et al. · 2009
Researchers exposed male rats to a static magnetic field at 128 mT for one hour per day over 30 consecutive days and then measured antioxidant enzyme activity, malondialdehyde concentration, and DNA oxidation in the brain. In the frontal cortex, exposure decreased glutathione peroxidase activity by 39%, CuZn superoxide dismutase activity by 35%, and catalase activity by 59%. In the hippocampus, exposure decreased CuZn-SOD activity by 51% and Mn-SOD activity by 13%, and increased malondialdehyde concentration by 32%. DNA oxidation was not detected, and the researchers suggested that an increase in metallothioneins in the frontal cortex may have protected DNA from oxidative damage.
Varró P, Szemerszky R, Bárdos G, Világi I. · 2009
Researchers exposed whole rats or excised rat brain slices to a 50 Hz electromagnetic field at 250–500 µT to examine effects on synaptic efficacy in the central nervous system. Slices treated directly ex vivo showed a decrease in basic synaptic activity, observed as a diminution in amplitude of evoked potentials. Following whole-body exposure, enhanced short- and long-term synaptic facilitation in hippocampal slices and increased seizure susceptibility in neocortical slices were observed. The researchers noted that the overall changes may strongly depend on the synaptic structure and neuronal network of the affected region, together with the specific spatial parameters and constancy of the EMF.
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.
Janać B, Tovilović G, Tomić M, Prolić Z, Radenović L. · 2009
Researchers exposed adult Wistar rats continuously to an extremely low frequency magnetic field (50 Hz, 0.5 mT) for 1, 3, and 7 days. The study examined serotonin 5-HT(2A) receptors in the prefrontal cortex and dopamine D(1) and D(2) receptors in the striatum, considering their involvement in motor behavior regulation. Serotonin 5-HT(2A) receptor affinity decreased and density increased in the prefrontal cortex, with the affinity effect being most prominent after 7 days of exposure. Dopamine D(1) and D(2) receptors in the striatum showed no significant effect on either affinity or density.
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.
Cvetkovic D, Cosic I. · 2009
Researchers tested whether a series of extremely low frequency magnetic field exposures at 50, 16.66, 13, 10, 8.33, and 4 Hz could alter relative power within corresponding brainwave bands. Thirty-three human subjects were tested under double-blind and counter-balanced conditions. Narrow alpha1 and alpha2 bands were significantly lower than control over temporal and parietal regions during the first exposure session, then significantly higher than control during the second session. The beta1 band showed a significant increase from before to after the 13 Hz first exposure session at the frontal region.
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.
Cook CM, Saucier DM, Thomas AW, Prato FS. · 2009
Researchers exposed 32 human subjects to two different pulsed magnetic field sequences that differed in presentation rate, to examine effects on the alpha frequency of the human EEG. Alpha activity was lowered over occipital-parietal regions during Sequence 1 exposure, while alpha activity over the same regions was higher after Sequence 2 exposure. These effects occurred after approximately 5 minutes of pulsed magnetic field exposure.
Balassa T, Szemerszky R, Bárdos G. · 2009
Researchers exposed rats to a 50 Hz electromagnetic field and then tested situational and social anxiety as well as locomotor activity. The tests used included the elevated plus-maze, novel object exploration, social interaction, and territoriality assessments. The researchers found that the field parameters may cause discomfort and may influence behavior, but there was no verified effect on social and territorial behavior.
Wiholm C et al. · 2009
Researchers studied the effects of a 2 1/2 h RF exposure at 884 MHz on spatial memory and learning using a double-blind repeated measures design. The exposure was designed to mimic that experienced during a real-life mobile phone conversation, with an average peak spatial specific absorption rate of 1.4 W/kg. Results showed a significant RF exposure by group effect on distance traveled during the trials, with the symptomatic group improving their performance during RF exposure while there was no such effect in the non-symptomatic group.
Söderqvist F, Carlberg M, Hansson Mild K, Hardell L · 2009
Researchers exposed 41 volunteers to a 30 min GSM 890 MHz signal at an average specific energy absorption rate distribution of 1.0 W/kg in the temporal area of the head. S100B showed no statistically significant increase, while transthyretin showed a statistically significant increase in the final blood sample 60 min after the end of the provocation compared to the sample taken immediately after provocation (p = 0.02). The researchers noted that the clinical significance of this finding, if any, is unknown.
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.
Nittby H et al. · 2009
Rats were exposed in TEM-cells for 2 hours at non-thermal specific absorption rates of 0, 0.12, 1.2, 12, and 120 mW/kg, and albumin extravasation over the blood-brain barrier, neuronal albumin uptake, and neuronal damage were assessed. Albumin extravasation was enhanced in the mobile phone exposed rats compared to sham controls after a 7-day recovery period, with a significant result at the SAR value of 12 mW/kg. There was a low but significant correlation between the exposure level and the occurrence of focal albumin extravasation.
Naziroğlu M, Gümral N. · 2009
Researchers divided thirty rats into five groups to study the effects of 2.45 GHz electromagnetic radiation on the brain's antioxidant system and EEG records. Exposed rats received 2.45 GHz electromagnetic radiation for 60 minutes per day for 28 days, after which EEG records and brain cortex samples were collected. Brain cortex concentrations of vitamin A, vitamin C, and vitamin E were lower in the exposed group than in controls, though these concentrations were increased by selenium and L-carnitine supplementation. L-carnitine appeared to have a more protective effect on vitamin concentrations than selenium.
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
de Tommaso M et al. · 2009
Researchers evaluated whether 900 MHz GSM phone exposure changed a brain electrical measure called the initial contingent negative variation (iCNV) in healthy volunteers using a double blind design. Ten healthy right-handed volunteers were evaluated, each recorded during a 10 min time interval in each of the three experimental conditions: a real emitting phone, a sham phone whose power was dissipated internally, and a phone switched off. The iCNV amplitude decreased and habituation increased during both the real and sham phone conditions compared with the off condition, with no significant prevalence of iCNV amplitude reduction on the left side, where the phones were located.
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.
Daniels WM, Pitout IL, Afullo TJ, Mabandla MV · 2009
Researchers studied the effect of electromagnetic radiation in the mobile phone range on the behaviour of the rat. Behavioural, histological and biochemical tests were performed on exposed and unexposed male and female rats to examine learning and memory, emotional states and corticosterone levels. No significant differences were found in spatial memory or brain morphology between groups, but some exposed animals showed decreased locomotor activity, increased grooming and a tendency of increased basal corticosterone levels. The researchers suggested that EMR exposure may lead to abnormal brain functioning.
Curcio G et al. · 2009
Researchers used functional near-infrared spectroscopy (fNIRS) to measure frontal cortex oxygenation in eleven healthy volunteers during a 40-minute exposure to a GSM mobile phone signal. The study found a slight linear increase in deoxygenated hemoglobin over time during real exposure, but no other measure showed GSM exposure-dependent changes. The researchers noted that their results should be confirmed on a larger sample size and using a multichannel instrument that allows the investigation of a wider portion of the frontal cortex.
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.
Kesari KK, Behari J. · 2009
Researchers investigated the effects of 50-GHz microwave radiation on the brain of Wistar rats. The animals were exposed for 2 hours a day for 45 days continuously at a power level of 0.86 μW/cm2. Exposed rats showed DNA double-strand breaks and a significant decrease in GPx and SOD activity in brain cells, while catalase activity showed a significant increase compared with control. PKC decreased significantly in the whole brain and hippocampus of the exposed group.
