Unknown authors · 1996
Researchers investigated interactions of weak ELFMFs with primitive haemopoietic cells in vitro using the multipotential progenitor cell line FDCP-mix(A4). They determined proliferative activity and clonogenic potential under optimal and sub-optimal growth conditions with exposures to ambient laboratory ELFMFs or three other ELFMF regimes including nulled fields, Ca2+-ion cyclotron resonance at 50 Hz, and vertical 50 Hz fields of 6 muT(RMS). Using exposures of 1, 4, 7 and 21 days, they found no significant alteration of growth rate, cell-cycle state or clonogenic efficiency.
Unknown authors · 1996
Exposure of breast cancer cells to 12 mG, 1 G, or 9 G 60-Hz electromagnetic fields failed to stimulate Cdk2 or cyclin B1-cdc2 activity or cyclin D1 synthesis. Simultaneous co-exposure to 60-Hz fields and chemical promoters did not enhance Cdk2 activation beyond the effect of the chemical promoter alone. Estrogen and xenoestrogens stimulated estrogen receptor binding to the estrogen receptor element, but EMF did not.
Sparks PB, Mond HG, Joyner KH, Wood MP · 1996
Researchers exposed 16 implanted Telectronics META pulse generators to simulated GSM transmissions and a 2-W digital mobile telephone. The devices were programmed to maximum sensitivity and tested in unipolar and bipolar settings and rate adaptive and nonrate adaptive modes. At maximum sensitivity, 11 of 16 devices showed no EMI, while brief ventricular triggering, pauses, and one episode of pacemaker-mediated tachycardia occurred in the remaining devices. When programmed to routine sensitivities, only one device displayed rare single beat ventricular triggering, and no changes in minute ventilation rate adaptive pacing were observed.
Maes A, Collier M, Slaets D, Verschaeve L. · 1996
Researchers exposed whole blood samples to a 954 MHz GSM base station antenna and then cultured lymphocytes with mitomycin C. They measured sister chromatid exchange frequencies in metaphase figures.
Irnich W, Batz L, Muller R, Tobisch R · 1996
Wolke S, Neibig U, Elsner R, Gollnick F, Meyer R, · 1996
Unknown authors · 1995
Researchers exposed B-lineage lymphoid cells to low energy electromagnetic fields and found stimulation of Lyn and Syk kinases. EMF exposure enhanced tyrosine phosphorylation in Syk-deficient cells but not in Lyn-deficient cells. Activation of Lyn kinase was found to be sufficient and mandatory for EMF-induced tyrosine phosphorylation.
Unknown authors · 1995
Researchers exposed human lymphoid cells immortalized by Epstein-Barr virus and HL60 leukemic cells to 50 Hz magnetic fields at 10 μT or 1 mT for periods ranging from 20 minutes to 72 hours. C-myc transcript levels were measured by Northern blot analysis normalized to the GaPDH gene. No statistically significant difference in c-myc transcript levels was observed between exposed and control cells for either cell type at any exposure duration, and the same result was found in cells synchronized in G0/G1 phase.
Unknown authors · 1995
Researchers performed an extensive series of experiments with human HL60 and Daudi cells incorporating blind exposures and internal standards. Exposure conditions covered flux densities from 5.7 microT to 10 mT and durations from 20 to 60 minutes. No alteration in the human MYC gene (c-myc) or beta-actin steady-state mRNA levels was observed.
Unknown authors · 1995
The study used quantitative Northern analysis to measure MYC and beta-actin mRNA levels in human leukemic HL60 cells. Cells were exposed to 60 Hz sinusoidal magnetic fields at 0.57, 5.7, or 57 microT for 20 minutes using a new field-exposure system designed to optimize any response. No significant effect of the electromagnetic fields on gene expression was observed with any of the exposure systems or analytical methods.
Semin IuA, Shvartsburg LK, Dubovik BV · 1995
Researchers studied the effect of weak radiofrequency radiation on DNA secondary structure stability in vitro. Exposure at 3 or 4 Hz and 0.6 mW/cm2 peak power significantly increased accumulated DNA damage, while other pulse rates or power levels eliminated the effect. DNA was incubated with glycine and formaldehyde, and damage was assessed via thermal denaturation dynamics.
Cao G, Liu LM, Cleary SF · 1995
Researchers exposed synchronized Chinese hamster ovary (CHO) cells to 27 MHz continuous-wave radio-frequency radiation for 2 hours at specific absorption rates of 5 or 25 W kg−1 under isothermal conditions, meaning no heating occurred. The exposure produced time- and dose-rate-dependent cell cycle alterations, with maximum responses occurring 3 days after exposure at a SAR of 25 W kg−1. Cells in G0/G1- or S-phase showed more pronounced alterations, while G2/M-phase cells showed minimal effects at either SAR.
Unknown authors · 1994
Researchers exposed SV40-transformed human fibroblasts to a 60 Hz continuous-wave sinusoidal electromagnetic field. Exposure resulted in increased levels of virally derived mRNA and protein of large T-antigen. The findings provide evidence that foreign DNA integrated into cells can be affected by EM fields under conditions known to cause increased transcripts from endogenous cellular genes.
Rosaspina S, Salvatorelli G, Anzanel D, Bovolenta R · 1994
Microwave exposure for 90 seconds provided effective, rapid sterilization of surgical scalpel blades contaminated with Candida albicans. Scanning electron microscopy showed that microwave irradiation induced a morphological modification of the cells. Longer exposure times caused greater alterations, with the microorganism fracturing after 9 minutes. Boiling water for the same duration killed the fungus but did not cause morphological alterations.
Zhao Z, Zhang S, Wang S, Yao Z, Zho H, Tao S, Tao L · 1994
The study aimed to investigate exposure limits for ultra-short wave radiation in work environments. Eighteen male rabbits were divided into four groups; three groups were irradiated with ultra-short waves at 100 MHz at power densities of 35, 1.5-3.5, and 0.07 mW/cm2 for 3 hours per day, 5 days per week for 24 weeks. Thermal effects occurred at 35 mW/cm2 and the thermal threshold limit value was set at 1.5 mW/cm2. An epidemiological survey of 136 factory workers and TV operators exposed to 0.2 mW/cm2 for over one year was compared with 108 controls. The exposure limit value for short wave radiation was set at 0.2 mW/cm2 using 15- and 20-fold safety factors.
Singh N, Rudra N, Bansal P, Mathur R, Behari J, Nayar U · 1994
Researchers exposed Twenty-three days old rats to 2.45 GHz microwaves at 1.0 mW/cm2 for sixty days and measured poly ADPR polymerase activity in various organs. The enzyme activity increased by 20% in liver and 35% in testis, while it decreased by 53% in brain diencephalon and 20% in cortex. No change was observed in spleen and kidney, and the changes were accompanied by alterations in NAD+ levels.
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.
Unknown authors · 1993
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
Researchers examined synthesis, degradation, processing, and steady-state levels of specific RNAs in human leukemia HL-60 cells exposed to ELF fields. Overall steady-state RNA levels measured by continuous and equilibrium 3H-uridine labeling were unchanged by ELF exposure. Northern blots showed ELF did not alter steady-state levels of c-myc, beta-actin, or 45S ribosomal RNA. A nuclease protection assay found ELF increased 45S ribosomal RNA transcription by 40-50% without substantially changing c-myc or beta-actin transcription, and pulse-chase labeling showed ELF accelerated processing and degradation of the 45S transcript, reducing its half-life from 115 to 85 minutes.
Unknown authors · 1993
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.
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.
Verma M, Dutta SK. · 1993
The study aimed to investigate microwave induced alteration in neuron specific enolase gene expression. Researchers exposed pNGE7 cells containing the neuron specific enolase gene to 915 MHz, 16 Hz AM radiation at SAR 0.05 mW/kg. Exposure resulted in elevation of neuron specific enolase, a diagnostic marker for neuron and lung cancer. Ion-exchange chromatography separated neuron specific enolase activity from non-neuronal enolase activity and showed altered expression of both.
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.
