Effect of electromagnetic radiation of the decimetric wave range on myocardium cell membranes

The decrease in the rate of lipid peroxidation and the increase in te fluorescence of chlortetracycline, bound with calcium ions absorbed on membrane surface after exposure thereof to decimeter waves, were revealed in myocardium cell membranes. Opposite changes were observed after the effect of p- chlormercuribenzoate . The effect of decimeter waves compensated the p- chlormercuribenzoate -induced changes.     

Effect of millimeter band electromagnetic radiation on a culture of sensory neurons from the chick embryo

The effect of extra-high frequency electromagnetic radiation (EHF EMR) on the development of organotypical culture of the spinal ganglia of a 9–10 day-old chick embryo was investigated. EMR with a wavelength of 5.6 mm and a rate of flow density <1.0, 4.0, and >100 mW/cm² was used. The stimulating action of EMR at rate of flow density of 4.0 mW/cm², manifested in intensification of the growth of neurites of sensory neurons and the proliferation of the peripheral glia, was observed. EHF EMR with a density >100 mW/cm² exerted inhibitory influence. The possibility of using the stimulating effect of EHF EMR in medical practice for intensifying regeneration in pathology and after trauma of the peripheral nervous system is discussed.Neirofiziologiya/Neurophysiology, Vol. 25, No. 3, pp. 175–179, May–June, 1993.     

Effect of low-intensity millimeter wave electromagnetic radiation on regeneration of the sciatic nerve in rats

The effect of low-intensity millimeter wave electromagnetic radiation (MWR) on regeneration of the rat sciatic nerve after transection and microsurgical reapproximation was examined. Rats were exposed to 54 GHz MWR at a power density of 4 mW/cm². It was found that MWR treatment of the femoral skin in the area of suture accelerated the regeneration of nerve fibers. At the twentieth postoperative day, the MWR-treated animals had a 32% increase in the regeneration distance compared to the control animals. The conduction velocity showed a 26% increase in the MWR-treated animals. © 1996 Wiley-Liss, Inc.     

Effect of pulse electromagnetic radiation on erythrocyte ghosts

The pulse microwave radiation has been shown to increase the fluorescence intensity of 2-toluidinonaphthanene-6-sulfonate (2,6-TNS) and 1-anilinonaphthalene-8-sulfonate (1,8-ANS) built-in membranes of erythrocyte ghosts. In experiments with 2,6-TNS a frequency dependence of the effect of microwave radiation with maximum within the frequency range of 55-65 Hz has been found. It is suggested that the changes registered with fluorescent probes are induced by mechanical oscillations generated by the pulse microwave radiation.     

Effects of millimeter band electromagnetic radiation of low intensity on sciatic nerve regeneration in rats

The effect of millimeter-band electromagnetic radiation of low intensity on the regeneration of the sciatic nerve was studied in experiments conducted on rats. The restoration of the functional properties of the nerve following its section and microsurgical suturing was investigated. It was established that irradiation of the site of operation stimulates the growth of nerve fibers and increases the conduction velocity of action potentials along the regenerating nerve.Translated from Neirofiziologiya, Vol. 25, No. 1, pp. 27–31, January–February, 1993.     

Modifying effect of low-intensive electromagnetic radiation on the irradiated cells

The normalising effect of low-intensive electromagnetic radiation on the viability of cell culture of L929 line, irradiated with gamma-quantums of 137Cs in a wide dose range was demonstrated.     

Modeling of the effect of modulated electromagnetic radiation on animal cells

Frequency-dependent modifications of intracellular free calcium concentration ([Ca2+]i) in neutrophils exposures to modulated extremely high frequency electromagnetic radiation were analyzed using a special mathematical model for [Ca2+]i oscillations. The model took into account the activation of Ca2+ influx into the cell by cytosolic Ca2+ and Ca(2+)-induced Ca2+ release from intracellular stores. The calcium channels of plasma membrane were chosen as a target for the influence of harmonic signal and additive noise in the model. The model simulation showed that in response to modulating signal, the rise in [Ca2+]i, has frequency dependence and phase dependence in relation to the moment of chemical stimulation. The phase-frequency dependence of the effect was observed at a certain sequence of delivery of chemical stimulus and modulating signal to the cell. At intensities of modulating signals exceeding the threshold, a rise in [Ca2+]i, reaching a level of more than 50% of the initial level, was observed at a frequency of about 1 Hz and in the phase range of 0.3-2.5 radians. The effect was found only at high intensities of chemical stimulus. The additive noise introduced into the system modified qualitatively and quantitatively the phase-frequency characteristics of the cell response to the modulating signal. An increase in noise intensity resulted in a displacement of the average frequency of the band of rise in [Ca2+]i, and then the emergence of a set of bands with a greater Q-factors. The analysis of dynamics of the nonlinear system in terms of the stability theory showed that, as the intensity of chemical stimulus increases, the system transits by means of a series of bifurcations from regular driving to chaotic, and then to oscillations, induced by a modulating harmonic signal. The boundary of the transition of oscillations from chaotic to induced ones corresponds to a specific "threshold" of the intensity of chemical stimulus for the significant rise in [Ca2+]i in response to the modulating signal. The results of the model analysis are in good correspondence with the experimental data obtained earlier, namely, with the effects of modulated extremely high-frequency electromagnetic radiation on neutrophils, which were observed only in the presence of Ca2+ in extracellular medium and at high concentrations of calcium ionophore A23187. Thus, as the characteristic frequency of the quasi-periodic process of calcium signalling in the cell coincides with the frequency of external field, a narrow-band rise in [Ca2+]i is observed, which can result in a modification of the functional activity of the cell.     

Effect of ionizing radiation on roses: Induction of somatic mutations

Bud-wood from seven rose cultivars exhibiting five different colors were exposed to 0, 3, 4, and 5 krad of gamma rays. A similar response was observed for all exposed cultivars; it included dose response reductions in bud-take, number and height of shoots, survival, flowers, petal weight and pollen fertility.The LD₅₀ for white and mauve-flowered cultivars was found to be lower than the yellow, red andpink-flowered ones; the latter were more prone to mutations. Many phenotypically detectable variations in leaf, flower and growth habit were recorded in irradiated populations. Only three mutations, one in growth habit and two in flower colors, were successfully isolated and propagated. The results suggest that the Floribunda rose, i.e., Pink Parfait was more suitable for induction of mutations as compared with the six Hybrid Teas.     

Role of synchronization in the action of weak electromagnetic signals of millimetric wavelength on living organisms

Possible mechanism of the influence of weak electromagnetic radiation on living organisms is discussed.     

Induced malignant genome reprogramming in somatic cells by testis-specific factors

Germline cell differentiation is controlled by a specific set of genes whose expression is tightly locked into the repressed state in somatic cells. Large-scale epigenome alterations, now evidenced in nearly all cancers, lead to aberrant activation of these normally silenced genes, as attested by the many reports describing the expression of testis-specific factors, known as cancer-testis genes, in various cancer cells. Here, based on the literature, we argue that off-context activity of some of the testis-specific epigenome regulators can reprogram the somatic cell epigenome toward a malignant state by favoring self-renewal and sustaining cell proliferation under stressful conditions, thereby constituting a major oncogenic mechanism.     

Effect of electromagnetic microwave radiation on the growth of Ehrlich ascites carcinoma

Daily exposure of mouse recipients of Ehrlich ascites carcinoma to electromagnetic radiation of the microwave range leads to a change in the dynamics of tumor growth by decreasing the total number of cells. The number of tumor cells with blebbing morphological signs after microwave radiation increases gradually with tumor growth. The maximum content of tumor cells in the state of blebbing is observed during active proliferation in tumor-recipient mice of the control group (without irradiation).     

Effect of electromagnetic radiofrequency radiation on the rats' brain, liver and kidney cells measured by comet assay

The goal of study was to evaluate DNA damage in rat's renal, liver and brain cells after in vivo exposure to radiofrequency/microwave (Rf/Mw) radiation of cellular phone frequencies range. To determine DNA damage, a single cell gel electrophoresis/comet assay was used. Wistar rats (male, 12 week old, approximate body weight 350 g) (N = 9) were exposed to the carrier frequency of 915 MHz with Global System Mobile signal modulation (GSM), power density of 2.4 W/m2, whole body average specific absorption rate SAR of 0.6 W/kg. The animals were irradiated for one hour/day, seven days/week during two weeks period. The exposure set-up was Gigahertz Transversal Electromagnetic Mode Cell (GTEM--cell). Sham irradiated controls (N = 9) were apart of the study. The body temperature was measured before and after exposure. There were no differences in temperature in between control and treated animals. Comet assay parameters such as the tail length and tail intensity were evaluated. In comparison with tail length in controls (13.5 +/- 0.7 microm), the tail was slightly elongated in brain cells of irradiated animals (14.0 +/- 0.3 microm). The tail length obtained for liver (14.5 +/- 0.3 microm) and kidney (13.9 +/- 0.5 microm) homogenates notably differs in comparison with matched sham controls (13.6 +/- 0.3 microm) and (12.9 +/- 0.9 microm). Differences in tail intensity between control and exposed animals were not significant. The results of this study suggest that, under the experimental conditions applied, repeated 915 MHz irradiation could be a cause of DNA breaks in renal and liver cells, but not affect the cell genome at the higher extent compared to the basal damage.     

Nuclear genome diversity in somatic cells is accelerated by environmental stress

DNA transfer to the nucleus from prokaryotic ancestors of the cytoplasmic organelles (mitochondria and plastids) has occurred during endosymbiotic evolution in eukaryotes. In most eukaryotes, organelle DNA transfer to nucleus is a continuing process. The frequency of DNA transposition from plastid (chloroplast) to nucleus has been measured in tobacco plants (Nicotiana tabacum) experimentally. We have monitored the effects of environmental stress on the rate of DNA transfer from plastid to nucleus by exploiting nucleus-specific reporter genes in two transplastomic tobacco lines. DNA migration from plastids to the nucleus is markedly increased by mild heat stress. In addition, insertions of mitochondrial DNA into induced double-strand breaks are observed after heat treatment. These results show that movement of organelle DNA to the nucleus is remarkably increased by heat stress.     

Age-related somatic structural changes in the nuclear genome of human blood cells

Structural variations are among the most frequent interindividual genetic differences in the human genome. The frequency and distribution of de novo somatic structural variants in normal cells is, however, poorly explored. Using age-stratified cohorts of 318 monozygotic (MZ) twins and 296 single-born subjects, we describe age-related accumulation of copy-number variation in the nuclear genomes in vivo and frequency changes for both megabase- and kilobase-range variants. Megabase-range aberrations were found in 3.4% (9 of 264) of subjects ≥60 years old; these subjects included 78 MZ twin pairs and 108 single-born individuals. No such findings were observed in 81 MZ pairs or 180 single-born subjects who were ≤55 years old. Recurrent region- and gene-specific mutations, mostly deletions, were observed. Longitudinal analyses of 43 subjects whose data were collected 7-19 years apart suggest considerable variation in the rate of accumulation of clones carrying structural changes. Furthermore, the longitudinal analysis of individuals with structural aberrations suggests that there is a natural self-removal of aberrant cell clones from peripheral blood. In three healthy subjects, we detected somatic aberrations characteristic of patients with myelodysplastic syndrome. The recurrent rearrangements uncovered here are candidates for common age-related defects in human blood cells. We anticipate that extension of these results will allow determination of the genetic age of different somatic-cell lineages and estimation of possible individual differences between genetic and chronological age. Our work might also help to explain the cause of an age-related reduction in the number of cell clones in the blood; such a reduction is one of the hallmarks of immunosenescence.     

Calcium protects differentiating neuroblastoma cells during 50 Hz electromagnetic radiation

Despite growing concern about electromagnetic radiation, the interaction between 50- to 60-Hz fields and biological structures remains obscure. Epidemiological studies have failed to prove a significantly correlation between exposure to radiation fields and particular pathologies. We demonstrate that a 50- to 60-Hz magnetic field interacts with cell differentiation through two opposing mechanisms: it antagonizes the shift in cell membrane surface charges that occur during the early phases of differentiation and it modulates hyperpolarizing K channels by increasing intracellular Ca. The simultaneous onset of both mechanisms prevents alterations in cell differentiation. We propose that cells are normally protected against electromagnetic insult. Pathologies may arise, however, if intracellular Ca regulation or K channel activation malfunctions.     

Aneugenic effect of ionizing radiation in mammalian and human somatic cells

Aneuploidy is among the most serious impairments of hereditary material in somatic and germline cells of living organisms. Chromosome loss or the appearance of an extra homolog in the chromosome set can result in either cell death or the development of various neoplasms with high probability of malignancy. It was traditionally believed that ionizing radiation produces primarily a clastogenic effect. However, there is apparently an aneugenic component of radiation, with mechanism different from that of structural chromosome damage. The present review focuses on the evidence for the existence of the aneugenic effect of ionizing radiation in mammalian and human somatic cells.     

Influence of electromagnetic radiation on molecular solitons

The soliton model of charge and energy transport in biological macromolecules is used to suggest one of the possible mechanisms for electromagnetic radiation influence on biological systems. The influence of the electromagnetic field (EMF) on molecular solitons is studied both analytically and numerically. Numerical simulations prove the stability of solitons for fields of large amplitude, and allow the study of emission of phonons. It is shown that in the spectra of biological effects of radiation there are two characteristic frequencies of EMFs, one of which is connected with the most intensive energy absorption and emission of sound waves by the soliton, and the other of which is connected with the soliton photodissociation into a delocalized state.