Enin LD, Akoev GN, Potekhina IL, Oleiner VD · 1992
The study aimed to investigate the effect of extremely high-frequency electromagnetic radiation on skin sensory endings in albino rats. Researchers recorded impulse activity from solitary fibers of the tibial nerve and found that receptor units responded to mechanical stimulation of the skin. Irradiation with low-intensity millimeter-band fields at 55.61 and 73 GHz reduced receptor unit sensitivity to mechanical stimulation. Half of the receptor units stopped responding 25 minutes after irradiation, while the other half continued responding after 35 minutes but with a significantly changed response character.
Dutta SK, Das K, Ghosh B, Blackman CF · 1992
Researchers examined the impact of radiofrequency radiation exposure on acetylcholinesterase activity. Neuroblastoma cells (NG108) exposed for 30 minutes to 147-MHz radiation amplitude-modulated at 16 Hz demonstrated enhanced acetylcholinesterase activity. The authors concluded that radiofrequency radiation affects both calcium-ion release and acetylcholinesterase activity in nervous system-derived cells in culture in a common dose-dependent manner.
Phelan AM, Lange DG, Kues HA, Lutty GA · 1992
Researchers exposed B16 melanoma cells to 2.45-GHz pulsed microwaves at 10 mW/cm² for 1 hour and measured membrane ordering using electron paramagnetic resonance. The exposure shifted the cell membrane from a more fluid-like phase to a more solid, ordered state. Similar membrane ordering occurred in melanin-reconstituted liposomes, but not in amelanotic cells or liposomes without melanin. Superoxide dismutase inhibited the microwave-induced ordering, implicating oxygen radicals as a cause.
Lai H, Carino MA, Horita A, Guy AW, · 1992
Researchers investigated which opioid receptor subtypes mediate a microwave-induced decrease in central cholinergic activity in rats. Rats were pretreated with specific antagonists of mu, delta, and kappa opioid receptors before exposure to microwaves. All three receptor subtypes were involved in the decrease in cholinergic activity in the hippocampus.
Kues HA et al. · 1992
Researchers exposed anesthetized monkeys to pulsed 2.45 GHz microwaves after topical treatment with timolol maleate or pilocarpine. Drug pretreatment lowered the power-density threshold for corneal endothelial lesions and increased iris vascular permeability from 10 to 1 mW/cm². Effects occurred at an average SAR of 0.26 W/kg and were confirmed with specular microscopy, fluorescein angiography, and horseradish peroxidase tracer techniques.
Czerska EM, Elson EC, Davis CC, Swicord ML, Czerski P · 1992
Researchers exposed human lymphocytes in vitro for 5 days to continuous-wave (CW) or pulsed-wave (PW) 2450-MHz radiation at non-heating and heating levels, with actual average SARs ranging to 12.3 W/kg. At non-heating levels, CW exposure did not affect spontaneous lymphoblastoid transformation, but PW exposure enhanced it significantly (P less than .002). At heating levels, PW exposure enhanced transformation to a greater extent than either conventional heating or CW heating, a finding significant at the .02 level.
Belyaev IYa, Alipov YD, Shcheglov VS, Lystsov VN · 1992
Researchers studied the effect of low-intensity microwaves on the conformational state of the genome of X-irradiated E. coli cells using the method of viscosity anomalous time dependencies. The frequency dependence of the observed effect had a resonance nature within the ranges of 51.62-51.84 GHz and 41.25-41.50 GHz, with a resonance half-width of the order of 100 MHz. A power density of 1 microW/cm2 was sufficient to suppress radiation-induced repair of the genome conformational state, across a tested range of 0.1-200 microW/cm2.
Garaj-Vrhovac V, Fucic A, Horvat D · 1992
Researchers exposed human whole-blood samples to continuous microwave radiation at a frequency of 7.7 GHz, at power densities of 0.5, 10, and 30 mW/cm2, for 10, 30, and 60 minutes. In all experimental conditions, the frequency of all types of chromosomal aberrations was significantly higher than in the control samples, and dicentric and ring chromosomes were detected in the irradiated samples. The results showed a positive correlation between micronuclei and specific chromosomal aberrations, including acentric fragments and dicentric chromosomes. The researchers indicated that microwave radiation causes changes in the genome of somatic human cells and that the applied tests are equally sensitive for the detection of the genotoxicity of microwaves.
Sandblom J, Theander S · 1991
Researchers examined the effects of microwaves on single-channel kinetics of gramicidin-A channels in lipid bilayer membranes. Microwave radiation did not affect single-channel conductance or channel lifetime beyond what would be expected from thermal effects. The rate of channel formation decreased during exposure, which is opposite to the effect expected from heating alone. The authors discussed the mechanism in terms of the dimerization process of channel formation. They attempted to separate thermal and athermal effects by measuring temperature at the membrane site and relating parameters to their known temperature dependence.
Khramov RN, Sosunov EA, Koltun SV, Ilyasova EN, Lednev VV · 1991
Researchers studied the effects of super high frequency microwaves (34-78 GHz) on spontaneous firing rates of slowly adapting stretch-receptor neurons in crayfish. Irradiation at power densities up to 250 mW/cm2 caused a transient decrease in firing rate, and after the field was turned off the rate increased and stabilized at pre-exposure levels. Firing rates also increased when the receptor muscle was stretched and were inversely correlated with small temperature increases of about 1.5°C. The response did not depend on frequency when temperature was held constant, and no resonant peaks were found across the millimeter-wave range.
Garson OM, McRobert TL, Campbell LJ, Hocking BA, Gordon I. · 1991
Researchers studied chromosome damage in 38 radio-linemen exposed to radio-frequency radiation and 38 matched controls. They analyzed Two hundred metaphases per person, scored blind, and found the rate of aberrant cells was the same in both groups. There were no statistically significant differences in the types of chromosome aberrations.
Ciaravino V, Meltz ML, Erwin DN · 1991
Researchers exposed Chinese hamster ovary cells to adriamycin and pulsed RFR at 2,450 MHz and 33.8 W/Kg for 2 h. The maximal temperature in the tissue-culture medium was 39.7 +/- 0.2 degrees C. The experiments were controlled for chemical and RFR exposures as well as for temperature. Verified statistically, the data indicate that the RFR did not affect changes in cell progression caused by adriamycin and did not change the number of sister chromatid exchanges induced by adriamycin.
Saalman E et al. · 1991
Researchers studied how 2.45 GHz microwave radiation affects the permeability of unilamellar liposomes containing a fluorescent marker. After 10 minutes of exposure, microwave-treated liposomes showed significantly greater marker release than those heated conventionally. The experiments were conducted above the lipid membrane's phase transition temperature, unlike earlier studies.
Spiers DE, Baummer SC · 1991
Researchers exposed Japanese quail eggs to 2,450 MHz microwaves at 5 or 20 mW/cm² for 8 hours daily from day 1 to 15 of incubation. At 30 °C ambient temperature, microwave exposure increased wet-embryo mass on day 16 by 9% at 5 mW/cm² and 61% at 20 mW/cm² compared to predicted masses without microwaves. Post-treatment tests showed no reliable indication that repeated microwave exposure resulted in abnormal physiological development. The authors concluded that microwave radiation can increase egg temperature and embryonic growth rate at below-normal incubation temperatures without altering basic metabolic and thermal characteristics.
Somosy Z, Thuroczy G, Kubasova T, Kovacs J, Szabo LD · 1991
Researchers exposed mouse embryo 3T3 cells to 2450 MHz continuous and 16 Hz square-modulated microwaves at absorbed energies from 0.0024 to 2.4 mW/g. Modulated waves caused more morphological changes than continuous waves at the same intensity. Cell surface negative charge decreased after modulated-wave exposure but was unchanged after continuous-wave exposure at the same dose. Modulated waves at 0.024 mW/g increased cell ruffling and caused cytoplasmic ultrastructural alterations, while continuous waves required higher doses of 0.24 and 2.4 mW/g for similar effects.
Lange DG, Sedmak J · 1991
Microwave exposure produced a dose-dependent increase in JEV-induced lethality. Hypercarbia at 5, 10, and 20% CO2 also produced a dose-dependent increase in JEV-induced lethality.
Lai H, Carino MA, Wen YF, Horita A, Guy AW · 1991
Rats were repeatedly exposed to pulsed, circularly polarized microwaves at 2,450 MHz with 2-microsecond pulses at 500 pps, a power density of 1 mW/cm², and a whole-body SAR of 0.6 W/kg. Ten 45-minute sessions increased muscarinic cholinergic receptor concentration in the hippocampus, while ten 20-minute sessions decreased concentration in the frontal cortex and hippocampus. Pretreatment with naltrexone at 1 mg/kg IP before each exposure session blocked these microwave-induced changes in cholinergic receptors.
Krause D, Mullins JM, Penafiel LM, Meister R, Nardone RM, · 1991
Researchers studied the effects of 2.45-GHz continuous-wave microwaves on interferon-regulated enzymes in murine L929 cells. Radioactive 2-5A binding to RNase L was 14.5% above control in sham-exposed samples and 36.4% above control in microwave-exposed samples. RNase L specific activity rose along with the increased 2-5A binding, but 2-5A synthetase specific activity showed no change. No detectable differences were noted in cell viability, plating efficiency, or proliferation rate after exposure.
Koveshnikov IV, Antipenko EN · 1991
Veyret B et al. · 1991
Researchers exposed Balb/C mice to pulsed microwaves at 9.4 GHz, both with and without amplitude modulation at frequencies between 14 and 41 MHz, to assess effects on the immune system. Exposure took place for five consecutive days at 10 hours per day, at a whole-body-averaged SAR of approximately 0.015 W/kg. When the pulsed field was combined with amplitude modulation, immune responses were significantly augmented or weakened depending on the AM frequency used, while the pulsed field alone did not greatly alter immune responsiveness.
Nageswari KS et al. · 1991
Researchers exposed fourteen male Belgian white rabbits to microwave radiation at 5 mW/cm2, 2.1 GHz, three hours daily, six days a week for three months, while seven rabbits received sham exposure for the same duration. Significant suppression of T lymphocyte numbers was found in the microwave group at two months and during follow-up. Despite lower T lymphocyte counts in the blood, no significant variation was observed in tissue T lymphocyte counts, and a functional immune response test showed no impairment.
Brown HD, Chattopadhyay SK · 1991
Researchers studied how 9.14 GHz continuous-wave microwave radiation affected ouabain inhibition of Na+/K+-ATPase from dog kidney. Exposure for 5 minutes to 9.14 GHz radiation at an estimated SAR of 20 W/kg was applied at several stabilized temperatures between 7.0 and 43.8 °C. The efficacy of ouabain as an inhibitor of ATPase activity was severely diminished by the microwave field, and at 24.9 °C a 23% decrease in activity occurred.
Balcer-Kubiczek EK, Harrison GH. · 1991
Researchers exposed actively growing cultures of C3H/10T1/2 cells for 24 hours to 2.45-GHz microwaves pulse-modulated at 120 Hz. The electromagnetic fields alone had no effect on cell survival or induction of neoplastic transformation. When combined with the tumor promoter TPA, the enhancement of transformation was highly significant and ranged up to a level equivalent to that produced by 1.5 Gy of X rays. The frequency of neoplastic transformation was dependent on the level of electromagnetic exposure and was additive with doses of X rays given as a cocarcinogen.
Garaj-Vrhovac V, Horvat D, Koren Z · 1991
Schwartz JL, House DE, Mealing GA · 1990
