Lokhmatova SA, · 1994
Researchers studied the effect of long-term impulsive electromagnetic irradiation at a power density of 0.25 mW/cm2 for 4 months, 2 hours per day, on rat testes and epididymides. The irradiation was at 3 GHz and the results demonstrated high sensitivity of the rat testes and epididymides, with destructive changes in seminiferous tubules and testicular tissue. Full recovery was not observed even 4 months after irradiation ended.
Krylova IN et al. · 1994
The study aimed to investigate the effect of ultrahigh-frequency electromagnetic radiation on learning and memory processes. Low-intensity electromagnetic field (12.6 cm, 2375 MHz, power density 1 mW/cm2) produced retrograde amnesia in the rat passive avoidance test. No effect was registered of microwave irradiation on the open field behavior and the pain sensitivity.
Dutta SK, Verma M, Blackman CF · 1994
Researchers exposed Escherichia coli cultures to electric and magnetic fields and measured the activity of enolase, an enzyme being tested clinically for detection of neoplasia. Exposure to a 147 MHz carrier wave amplitude-modulated at 16 Hz enhanced enolase activity by 62%, while modulation at 60 Hz reduced it by 28%. Exposure to 16 Hz fields alone enhanced enolase activity by 59%, while 60 Hz fields alone reduced activity by 24%. Sham exposures and continuous-wave 147 MHz radiation showed no change in enolase activity.
Akoev IG, Mel'nikov VM, Usachev AV, Kozhokaru AF, · 1994
Researchers studied whether exposure to low-intensity radiofrequency radiation after a lethal dose of gamma-radiation could modify the resulting injury in mice. The radiofrequency exposure lasted up to 23 hours at an intensity of 5 plus or minus 1.5 microwatts per square centimeter, covering frequency ranges of 2-8, 8-18, and 19-27 GHz with a swing frequency of 12-14 Hz. A clearly pronounced modification of acute radiation injury was obtained when the radiofrequency exposure was applied immediately after the gamma-radiation.
R. Goodman et al. · 1994
The study examined how low-frequency electromagnetic fields affect levels of hsp70 transcripts in cells. In yeast cells, the SSA1 gene, which is homologous to hsp70, was found to be elevated when cells were exposed to electromagnetic fields at 0.8 to 80 μT. The researchers noted that the pattern of gene induction appeared to be related to the stress response model for heat shock.
Haider T, Knasmueller S, Kundi M, Haider M · 1994
Researchers used the Tradescantia-micronucleus bioassay to test whether short-wave electromagnetic fields used for broadcasting (10–21 MHz) may show genotoxic effects. Plant cuttings bearing young flower buds were exposed for 30 hours at various distances from broadcasting antennas, and micronucleus frequencies were compared to laboratory controls. Higher micronucleus frequencies were found at all exposure sites near the antennas where IRPA electric field strength standards were exceeded, and results at all but one site were statistically significant.
Unknown authors · 1993
Researchers measured intracellular calcium concentration in mouse lymphocytes using a fluorescent probe during a 60-minute exposure to cyclotron resonance conditions for calcium ions. They tested resonance conditions at 16 Hz and 50 Hz with DC field amplitudes shifting the frequency up to 25 percent either side of the calculated optimum. Concanavalin A treatment increased intracellular calcium significantly, but no change was detected under any magnetic field combination tested.
Unknown authors · 1993
Ulashchik VS · 1993
The study aimed to investigate changes in drug pharmacokinetics and pharmacodynamics under the influence of microwaves of different ranges. Human and animal experiments were conducted to compare the effect of microwaves of different ranges on drug pharmacodynamics and pharmacokinetics. The results suggested that microwaves could potentiate and prolong the action of some drugs.
Schwartz JL, Mealing GA · 1993
Researchers investigated the effects of AM or CW modulated 1 GHz exposure on calcium efflux and contractile force of isolated atrial muscle stripes of frog heart in vitro. Calcium efflux from electrically stimulated, 45Ca(2+)-preloaded atrial strips of the frog heart was measured from perfusate samples collected at 2-min intervals for 32 min while contractile force was simultaneously monitored. The atrial strips were exposed for 32 min to constant or amplitude-modulated 1 GHz fields at SAR ranging from 3.2 microW/kg to 1.6 W/kg with modulation at 0.5 Hz or 16 Hz. Neither unmodulated nor 0.5 Hz or 16 Hz modulated 1 GHz waves affected the movement of calcium ions or the contractile force in isolated atrial strips of the frog heart.
Rotkovska D, Bartonickova A, Kautska J · 1993
Kunjilwar KK, Behari J · 1993
Researchers exposed developing rats to amplitude-modulated radio frequency radiation at 147 MHz and its sub-harmonics for 30 to 35 days, three hours per day. A significant decrease in acetylcholine esterase activity was found in exposed rats compared to controls. The decrease in enzyme activity was independent of the carrier wave frequencies used. Short-term exposure did not significantly affect acetylcholine esterase activity.
Maes A, Verschaeve L, Arroyo A, De Wagter C, Vercruyssen L · 1993
Researchers exposed human peripheral blood lymphocytes to 2450 MHz microwaves for 30 and 120 minutes at constant body temperature. Exposure caused a marked increase in chromosome aberrations, including dicentric chromosomes and acentric fragments, and micronuclei. Microwave exposure did not influence cell kinetics or sister chromatid exchange frequency.
Fisun OI · 1993
Researchers derived the dispersion relation for intrinsic cellular electrical oscillations from hydrodynamic equations for surface ions inside and outside a cell. They calculated properties for surface-plasmon modes and for a resonant response of a charged membrane bilayer to microwave pumping.
Somosy Z, Thuroczy G, Kovacs J · 1993
Researchers investigated pyroantimonate-precipitable calcium in mouse intestinal epithelial cells after whole-body exposure to 2450 MHz continuous and 16 Hz square-modulated microwaves. Immediately after modulated irradiation at 0.5 and 1 mW/cm², calcium deposits rapidly appeared on the cytoplasmic side of lateral membranes and in the junctional complex including tight junctions. These changes were reversible, with calcium distribution returning to control-like patterns after 24 hours. Continuous-wave exposure at the same energy did not alter calcium distribution.
Seaman RL, DeHaan RL · 1993
Researchers studied inter-beat intervals of aggregated cardiac cells from chicken embryos during 190-second exposures to 2.45 GHz microwaves. The inter-beat interval decreased during exposures at 42.0 W/kg and higher with continuous-wave or square-wave modulation, consistent with thermal effects. Increases occurred during continuous-wave exposures at 1.2-12.2 W/kg and decreases after pulse-modulated exposures at 8.4-12.2 W/kg, which were not consistent with simple thermal effects.
Pakhomov AG · 1993
Researchers investigated effects of 915 MHz pulsed microwave radiation with peak SAR 20-30 W/g on isolated frog nerve cords. Nerve heating did not exceed 2.2°C due to intense Ringer's solution perfusion. Irradiation during stimulation significantly decreased action potential amplitude and peak latency, while conventional heating increased amplitude, supporting a non-thermal mechanism.
Litovitz TA, Krause D, Penafiel M, Elson EC, Mullins JM, · 1993
The study investigated the role of coherence time in the effect of microwaves on ornithine decarboxylase activity. Amplitude-modulated 915 MHz microwaves at SAR 2.5 W/kg modulated at 55, 60, or 65 Hz approximately doubled ornithine decarboxylase activity after 8 h, and switching modulation frequencies at coherence times of 1.0 s or less abolished the enhancement while times of 10 s or longer provided full enhancement.
Lange DG, D'Antuono ME, Timm RR, Ishii TK, Fujimoto JM. · 1993
Field AS, Ginsburg K, Lin JC · 1993
Researchers studied the effects of pulsed microwaves on membrane input resistance and action potential interval statistics in spontaneously active ganglion neurons of land snails (Helix aspersa). Experiments were conducted at strictly constant temperature, so macroscopic heating was not responsible for any observed effects. Exposure significantly increased mean input resistance, while mean firing rate and mean input current were not affected. The net input current was found to be more variable in exposed neurons, though changes in interspike interval standard deviation and input current autocorrelation were not consistent across neurons.
Ellingsrud S, Johnsson A · 1993
Researchers studied the up-and-down rhythmic movements of the lateral leaflets of Desmodium gyrans when exposed to electromagnetic radiation in the radio-frequency range. The RF radiation was applied as homogeneous 27.12 MHz fields in specially-designed exposure cells, and in some cases as non-homogeneous radiation of 27 MHz amplitude modulated by 50 Hz in front of commercial diathermy equipment. The radiation caused temporary changes in amplitude, period, and phase, and could also cause temporary or complete cessations of the rhythms.
Unknown authors · 1992
The study used an ultrasensitive superconducting magnetometer to detect ferromagnetic material in various human brain tissues. High-resolution electron microscopy identified the minerals as belonging to the magnetite-maghemite family, with crystal morphologies resembling those produced by magnetotactic bacteria and fish. The measurements imply at least 5 million single-domain crystals per gram in most brain tissues and over 100 million per gram in the pia and dura.
Bolshakov MA, Alekseev SI · 1992
Researchers recorded spontaneous electrical activity and ionic currents of Lymnea stagnalis neurons during exposure to a 900-MHz field using modified microelectrode and voltage-clamp techniques. When subjected to pulsed waves, rapid burst-like changes in the firing rate of neurons occurred at SARs of a few W/kg. The effect was dependent on modulation but not on modulation frequency, with a threshold SAR near 0.5 W/kg. Continuous-wave radiation had no effect on the firing rate pattern at the same SAR. Mediator-induced activation of acetylcholine, dopamine, serotonin, or GABA receptors was not altered during either exposure, indicating these receptors were not responsible for the bursting effect.
Saffer JD, Profenno LA · 1992
Fucic A, Garaj-Vrhovac V, Skara M, Dimitrovic B · 1992
Researchers used the micronucleus assay with a new mathematical approach to separate clastogenic from aneugenic activity of vinyl chloride monomer, X-rays, and microwaves on human somatic cells. Comparison of micronucleus size distributions in lymphocytes from exposed humans showed X-rays and microwaves were preferentially clastogens while vinyl chloride monomer showed aneugenic activity as well. The authors noted that microwaves possess some mutagenic characteristics typical of chemical mutagens.