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PubMedDate not supplied

Action of modulated electromagnetic fields on the emotional component of the systems organization of behavioral acts in rats.

This article reviews experimental data providing evidence on the effects of modulated electromagnetic fields of 30-120 V/m with a carrier frequency of 30 MHz modulated sinusoidally at frequencies of 2-50 Hz on the emotional responses accompanying various stages in the systems organization of behavior in rats. The blocking effects of fields were demonstrated in self-stimulation models in different types of conditioned reflex behavior, as well as during extinction of conditioned reflex responses in individual conditions and emotional intercourse. It is suggested that modulated electromagnetic fields which have information effects on the body act on the information component of behavior, i.e., emotion.

Animals↗

PubMed2006

Influence of ELF sinusoidal electromagnetic fields on proliferation and metabolite yield of fungi.

The response of mycelium proliferation in 12 strains of fungi were tested by sinusoidal ELF 50 Hz electromagnetic field treatment in the range B = 0.6-10 mT over 10 days. The ratio of experiment/control indicated three types of proliferation changes: a) no significant change, b) a strong decrease down to E/C = 0.2, c) a maximization of mycelium diameter by treatment at 5-7 mT. According to these results, effects can be produced noninvasively by varying either magnetic intensities or time of treatment. As yet, systematic bioelectromagnetic research using sinusoidal electromagnetic fields (SEMF)-on fermentation of fungi is still in its initial stages.

Cell Division↗

PubMed1994

[Low frequency electromagnetic fields in the working environment--exposure and health effects. Elevated risk of cancer, reproductive hazards or other unwanted health effects?].

The authors describe the physical properties of low frequency electromagnetic fields and occupational exposure to such fields in different working environments. They discuss possible health effects reported in the literature. It is concluded that there seems to be elevated risk of leukemia and brain tumours among persons employed in "electrical work", though there is insufficient evidence that the fields are responsible. No conclusion can be drawn as to risk of adverse outcome of pregnancy. When this is technically and economically feasible, exposure to low frequency electromagnetic fields should be kept to a minimum.

Electromagnetic Fields↗

PubMedDate not supplied

[Hygienic evaluation of the combined effect of electromagnetic fields and pesticides in experimental conditions].

The paper deals with the evaluation of combined effects of some natural and anthropogenic factors that are typical of the Kursk magnetic anomaly region by means of dispersion analysis in the experiments on albino rats and mice. The resultant signs were the indices of animal deaths, nonspecific protective factors, immune responses, changes in body weight, etc. A higher geomagnetic field can modify the biological effects of exposure to agricultural chemicals. The combined effects of a static electromagnetic field with induction of 300 microT to 0.3 T and of chlorpyrifos at various concentrations (0.1, 1, 50, and 100 mg/kg) were found to potentiate the toxic properties of the pesticide. The proportion of the potentiation effects increased as the intensity of the studied factors rose. The dispersion analysis established a predominant role of chlorpyrifos in the combined effects of the factors on the death of animals, serum complementary activity, antibody- and rosette-forming cells of the spleen and other lymphoid organs. The role of a static electromagnetic field is prevalent in the formation of effects of the intensity and completeness of phagocytosis.

Animals↗

PubMed1991

Reproductive integrity of mammalian cells exposed to power frequency electromagnetic fields.

Human lymphocytes and Chinese hamster ovary (CHO) fibroblasts were analyzed for cytogenetic and cytotoxic endpoints to determine whether exposure to power frequency (60 Hz) electromagnetic fields (EMF) interferes with normal cell growth and reproduction. An exposure chamber was built to apply variable electric current densities of 3, 30, 300, and 3,000 microA/cm2, simultaneously with a fixed magnetic field of 2.2 G to proliferating cells. The current densities were chosen to bracket those that may be induced in the human body by fields measured beneath high voltage (765 kV) power transmission lines. The electric current was applied through the media of a cell culture chamber positioned between two stainless steel electrodes but separated from direct contact with the culture media by a salt bridge composed of a 1% agarose gel. The magnetic field was generated using two pairs of Helmholtz coils driven 73 degrees out of phase producing an elliptically polarized magnetic field 36 degrees out of phase with the electric field. The EMFs were measured and mapped inside the cell culture chamber to insure their uniformity. CHO cells were exposed continuously for 24-96 hr (depending on experiment) and human lymphocytes were exposed continuously for 72 hr. The EMFs were monitored throughout the entire treatment period using a multichannel chart recorder to verify continuous application of the desired fields. Sister-chromatid exchange and micronuclei were monitored to evaluate the potential for genotoxicity. In addition, standard growth curves, clonogenicity, and cell cycle kinetics were analyzed to evaluate possible cytotoxic effects. The experimental data consistently showed that the growth rate and reproductive integrity of both cell types was unaffected by exposure to the electromagnetic fields.

Animals↗

PubMed2003

[The efficacy of pulsed electromagnetic fields used alone in the treatment of femoral head osteonecrosis: a report of two cases].

Long-term radiologic and clinical results of pulsed electromagnetic fields (PEMF) are presented with illustration of two patients having Ficat-Arlet grade 2 osteonecrosis of the femoral head. One patient (female, age 33 years) had bilateral involvement due to systemic steroid use, the other (male, age 39 years) had right-sided involvement of unknown etiology. Surgical treatment was ruled out because of aplastic anemia associated with significant thrombocyte deficiency in the first patient, while the other refused surgery. Pulsed electromagnetic fields were applied as the sole treatment modality in three hips for six months with a duration of 10 hours daily (at nights). At the end of 12-year- and five-year-follow-ups, respectively, clinical improvement was observed in all hips, with no radiologic deterioration. It is concluded that application of PEMF stimulation alone may be an alternative treatment modality in patients in whom surgical treatment cannot be performed for femoral head osteonecrosis, in particular Ficat-Arlet grade 1 and 2 disease.

Adult↗

PubMed1989

Effects of noise and electromagnetic fields on reproductive outcomes.

Much public health research has been directed to studies of cancer risks due to chemical agents. Recently, increasing attention has been given to adverse reproductive outcomes as another, shorter-term biologic indicator of public health impact. Further, several low-level ubiquitous physical agents have been implicated recently as possibly affecting human health. These physical factors (noise and electromagnetic fields) represent difficult topics for research with epidemiologic study methods. This paper provides a brief review of the published data related to the risk of adverse reproductive outcomes and exposure to noise or electromagnetic fields. The discussion includes ideas for possible biologic mechanisms, considerations for exposure assessment, and suggestions for epidemiologic research.

Abortion, Spontaneous↗

PubMed2006

[Influence of the chronic exposure to network frequency electromagnetic field on rats under interrupted and continuous action of EMF].

The aim of the study was the investigation of chronic exposure to network frequency electromagnetic field in the rats under interrupted or continuous action of electric magnetic field. We were studying their behavior by the method of "open field". Comparison of behavior of rats in the "open field" has shown that the significant difference in the emotional activity of rats was stated. The number of boluses and urination in rats of B group is 4,5 times more than in the individuals of C group (p<0,001), but the significant difference between the rats of control A and B groups has not been stated. Although, the number of boluses in the rats of B group was a little raised, this raise was not statistically significant (p<0,5). The rats of control A and C groups significantly distinguished from one another. The number of boluses and urination in the animals of C group was significantly lower (p<0,001). In that way, the rats which were under the discontinuous action of electromagnetic field were distinguished by high emotionality, which occur by increase of boluses and urination, the high number grooming behavior and increase of the number of translocation, that influences the functioning of hypothalamohypophysial system.

Animals↗

PubMed1997

Electromagnetic fields can affect osteogenesis by increasing the rate of differentiation.

Electromagnetic fields of various kinds can alter osteogenesis in animals with osteotomies and patients with nonunions, but the underlying cellular mechanisms are unknown. The aims of this study were to determine whether I gauss at 60 Hz affected periosteal proliferation and differentiation in either the normal rat tibia or 1 to 14 days after a surgically induced defect. In the injured rats, using histologic study, autoradiography, and morphometry, it was found that exposure for 1 or 3 days had no effect on proliferation but that it produced an increase in osteoblasts 3 days after the injury. Proliferation and differentiation were unaffected by exposure in the absence of injury. The results suggest that the primary effect of the fields was to promote differentiation but not proliferation. Because fields can stimulate proliferation of osteoblastlike cells in vitro, the results of this study may indicate the presence of an in vivo factor that antagonizes the tendency of fields to increase mitotic activity.

Animals↗

PubMed2005

Connection between electric and magnetic coherence in free electromagnetic fields.

We introduce quantitative measures for the description of the electric and magnetic coherence in a stationary, random electromagnetic field at two points, in a volume, and in the Fourier space. These quantities are applied to free electromagnetic fields, and several theorems regarding the relationship between the two types of coherences in such fields are established. Fields which are statistically homogeneous, and those which, in addition, are statistically isotropic are considered separately. Furthermore, the connection between the electric and magnetic coherence is exemplified for some specific statistically homogeneous fields.

Journal Article↗

PubMed1997

Short cycles of both static and pulsed electromagnetic fields have no effect on the induction of cytokines by peripheral blood mononuclear cells.

We evaluated the effect of short cycles of static and pulsed electromagnetic field exposure on the eventual activation of peripheral blood mononuclear cells. The cells were subjected to three 15-min cycles of EMF, each exposure being followed by 105 min without a field, for a total of 6 hr. The results clearly demonstrate that the proliferative responses of both normal cells and cells stimulated with 1 microg/ml phytohemagglutinin were not distinguishable from control cells not exposed to EMF. Moreover, although the production of interleukin-2, interferon gamma and tumor necrosis factor alpha increased during the first 48 hr of incubation, the values remained unchanged with respect to controls. This indicates that brief exposure to an electromagnetic field has no significant effect on peripheral blood mononuclear cells. The comparison between biological activity and the cytokine antigen present in our samples indicated that the recovery of antigen corresponded to an equal recovery of biological activity, suggesting the absence of either qualitative differences in these proteins or the impairment of transcriptional and translational processes.

Cell Division↗

PubMed2002

The effect of electromagnetic field on undescended testis after orchiopexy.

Undescended testis is a common problem leading to infertility. After orchiopexy some studies support the necessity of hormonal therapy. Electromagnetic field stimulation on living tissues increase cell proliferation, protein and DNA synthesis. Sixteen prepubertal rats was objected to the fixation of left testes to the anterior abdominal wall for 30 days, right testes were removed. Another group of sixteen rats objected only to the right orchiectomy and a manipulation simulating study group without fixation. After orchiopexy, animals were divided into two groups. Both groups had eight rats. Electromagnetic field (EMF) stimulation group had the stimulation for two hours every day for ten days, while the second group did not. The sham group also divided into two groups. The first one applied EMF and name as Group CEM, the second one was sham. Weight of removed testes were measured and fixed in 10% formaldehyde for histopathological evaluation. At the creating of undescended testis and right orchiectomies a blood sample was obtained for testosterone level of prepubertal rats. After finishing EMF stimulation the rats were mated with females for 17 days. After fertility study a blood sample was obtained for testosterone assay and body weight were measured and fixed in formaline for histopathologic evaluation. All the rats were killed with overdose ether anesthesia and number of fetuses were recorded. Histopathological evaluation was based on Johnsen criteria and seminiferous tubule diameter measurements. We conclude that EMF stimulation resulted in Leydig cell proliferation, increase in testosterone level, testis weight, but decrease in germ cell population.

Analysis of Variance↗

PubMed2001

Growth and differentiation of PC6 cells: the effects of pulsed electromagnetic fields (PEMF).

Previous studies in our laboratory showed that neurite outgrowth in vitro and nerve regeneration in vivo were stimulated by 2 Hz, 0.3 mT (3 G) pulsed electromagnetic fields (PEMF). To learn more about the effects of PEMF on nerve cells, we exposed PC6 cells, a standard neuronal-like cell model, to the same pulsed electromagnetic fields for 2 h/day for 2 days and asked whether two different cell processes, proliferation and differentiation, were affected. The cells were also treated with a differentiating agent, nerve growth factor (NGF), to further define any interactive effects. We found that proliferation was unaffected by either PEMF or NGF alone or in combination. Differentiation, expressed as neurite outgrowth, was strongly upregulated with NGF, but this NGF response was significantly depressed in cells treated with PEMF.

Animals↗

PubMed2004

Theory of partially coherent electromagnetic fields in the space-frequency domain.

We construct the coherent-mode representation for fluctuating, statistically stationary electromagnetic fields. The modes are shown to be spatially fully coherent in the sense of a recently introduced spectral degree of electromagnetic coherence. We also prove that the electric cross-spectral density tensor can be rigorously expressed as a correlation tensor averaged over an appropriate ensemble of strictly monochromatic vectorial wave functions. The formalism is demonstrated for partially polarized, partially coherent Gaussian Schell-model beams, but the theory applies to arbitrary random electromagnetic fields and can find applications in radiation and propagation and in inverse problems.

Journal Article↗

PubMed2005

[Effect of electromagnetic field produced by mobile phones on the activity of superoxide dismutase (SOD-1)--in vitro researches].

The aim of the paper was to estimate in vitro the effect of electromagnetic field produced by mobile phones on the activity of superoxide dismutase (SOD-1) in human blood platelets. Suspension of blood platelets exposed to the electromagnetic field of 900 MHz frequency for 1, 3, 5, 7 minutes. Our studies demonstrated that microwaves produced by mobiles significally depleted the activity of SOD-1 after 1, 5, 7 min. of exposition and increased after 3 min. nn comparison wit control test. On the ground of our results we conclude that oxidative stress after exposition to microwaves can be the reason of many disadvantageous changes in cells and may cause many systemic consequences in human organism.

Adult↗

PubMed2006

Genotoxic effects of exposure to radiofrequency electromagnetic fields (RF-EMF) in cultured mammalian cells are not independently reproducible.

Conflicting results have been published regarding the induction of genotoxic effects by exposure to radiofrequency electromagnetic fields (RF-EMF). Using the comet assay, the micronucleus test and the chromosome aberration test with human fibroblasts (ES1 cells), the EU-funded "REFLEX" project (Risk Evaluation of Potential Environmental Hazards From Low Energy Electromagnetic Field Exposure Using Sensitive in vitro Methods) reported clearly positive effects for various exposure conditions. Because of the ongoing discussion on the biological significance of the effects observed, it was the aim of the present study to independently repeat the results using the same cells, the same equipment and the same exposure conditions. We therefore exposed ES1 cells to RF-EMF (1800 MHz; SAR 2 W/kg, continuous wave with intermittent exposure) for different time periods and then performed the alkaline (pH>13) comet assay and the micronucleus test (MNT). For both tests, clearly negative results were obtained in independently repeated experiments. We also performed these experiments with V79 cells, a sensitive Chinese hamster cell line that is frequently used in genotoxicity testing, and also did not measure any genotoxic effect in the comet assay and the MNT. Appropriate measures of quality control were considered to exclude variations in the test performance, failure of the RF-EMF exposure or an evaluation bias. The reasons for the difference between the results reported by the REFLEX project and our experiments remain unclear.

Animals↗

PubMedDate not supplied

Fundamental issues on electromagnetic fields (EMF).

This paper will examine the fundamental principals of Electromagnetic Field Radiation. The discussion will include: The basic physical characteristics of magnetic and electric fields, the numerous sources of EMF in our everyday lives, ways to detect and measure EMF accurately, what to look for in EMF instruments, and the issues and misconceptions on shielding and exposure reduction.

Computer Terminals↗

PubMed1998

Alteration of diurnal rhythms of blood pressure and heart rate to workers exposed to radiofrequency electromagnetic fields.

BACKGROUND: In previous studies we found measurable effects on variability of heart rate and on blood-pressure parameters of workers exposed to radiofrequency electromagnetic fields (EMF)compared with a control population, but none of the effects could be assigned clinical significance. In general, the obtained results strongly suggested that dysregulation of the autonomic control of the circulatory system was occurring. Therefore, it seemed logical that analysis of diurnal rhythms of blood pressure and heart rate, on the basis of data from 24 h recordings, might further support the above hypothesis. OBJECTIVE: The aim of this study was to determine the course of diurnal rhythms of blood pressure and heart rate in a group of workers exposed to various intensities of radiofrequency electromagnetic fields. METHODS: In the study we used 61 healthy workers (aged 30-50 years) who had been exposed to radiofrequency EMF of 0.738-1.503 Mhz and 42 healthy workers at radio-line stations (aged 28-49 years), who had not been exposed to EMF occupationally. The work patterns of these two groups were identical (12 h day working shift, 24 h interval, 12 h night shift and then 48 h rest). During the second day of the rest period 24 h ambulatory blood pressure (ABP) was recorded. For analysis of diurnal rhythms the group of exposed workers was divided into two subgroups: group A of 38 subjects exposed to low intensities of radiofrequency EMF (20-180 V/m) and group B of 23 subjects exposed to high intensities of radiofrequency EMF (200-550 V/m). Parameters of diurnal rhythms of blood pressure and heart rate (acrophase, amplitude and mean) were calculated by performing a least-square fit of a 24 h cosinor (single cosinor analysis) at P < 0.05. RESULTS: Healthy men aged 28-49 years, working on a pattern of 12-24-12-48 h, exhibited typical, well-preserved diurnal rhythms of blood pressure and heart rate with two maxima (at about 1400 and 1700-1800 h) and one minimum (at about 0200-0400 h). For workers exposed to radiofrequency EMF we noted a significant lowering of the amplitudes of rhythms of blood pressure and heart rate (P < 0.01) and a shift of the acrophase to an earlier time (1100-1200 h; P < 0.05). These changes were more pronounced among workers exposed to high intensities of radiofrequency EMF. CONCLUSIONS: Occupational exposure to radiofrequency EMF can result in changes of the diurnal rhythms of blood pressure and heart rate with lowering of their amplitudes and a shift of the acrophase. The clinical relevance of the present finding needs to be investigated in further studies.

Adult↗