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A number of effects of weak combined (static and alternating) magnetic fields with an alternating component of tens and hundreds nT at a collinear static field of 42 microT, which is equivalent to the geomagnetic field, have been found: the activation of fission and regeneration of planarians Dugesia tigrina, the inhibition of the growth of the Ehrlich ascites carcinoma in mice, the stimulation of the production of the tumor necrosis factor by macrophages, a decrease in the protection of chromatin against the action of DNase 1, and the enhancement of protein hydrolysis in systems in vivo and in vitro. The frequency and amplitude ranges for the alternating component of weak combined magnetic fields have been determined at which it affects various biological systems. Thus, the optimal amplitude at a frequency of 4.4 Hz is 100 nT (effective value); at a frequency of 16.5 Hz, the range of effective amplitudes is broader, 150-300 nT; and at a frequency of 1 (0.5) Hz, it is 300 nT. The sum of close frequencies (e.g., 16 and 17 Hz) produces a similar biological effect as the product of the modulating (0.5 Hz) and carrying frequencies (16.5 Hz), which is explained by the ratio A = A0sin omega1t + A0sin omega2t = A0sin(omega1 + omega2)t/2cos(omega1 - omega2)t/2. The efficiency of magnetic signals with pulsations (the sum of close frequencies) is more pronounced than that of sinusoidal frequencies. These data may indicate the presence of several receptors of weak magnetic fields in biological systems and, as a consequence, a higher efficiency of the effect at the simultaneous adjustment to these frequencies by the field. Even with consideration of these facts, the mechanism of the biological action of weak combined magnetic fields remains still poorly understood.

In vitro effects of low-level electromagnetic waves (8.18 GHz, frequency swings within 1 s, intensity 1 microW/cm, exposure for 1 h) and low-energy laser light (He-Ne laser with 632.8 nm, 0.2 mW/cm, dose 1.2 x 10(-2) J/cm2) on the expression of receptor protein TLR4, which is known as a part of the system for microbal toxin recognition, were studied in mouse lymphocytes. In addition, TLR4 expression was examined in situations when stress responses to low-level nonionizing radiation were modified by the antibiotic geldanamycin, which suppresses the activity of the heat shock protein Hsp90. It was found that low-level microwaves significantly raised the amount of TLR4; in contrast, laser light decreased the expression of the receptor in lymphocytes. In cells pretreated with geldanamycin, the TLR4 expression in irradiated cells was reduced to minimum levels, much lower than control values. The results showed that TLR4, which is involved in specific binding of toxin from gram-negative bacteria, can regulate cell responses to signals of other origin, in particular to nonionizig radiation, including low-level microwaves and laser light.

The effects of millimeter (40 GHz) and centimeter (8.15-18.00 GHz) low-intensity waves on the production of tumor necrosis factor (TNE) in macrophages and lymphocytes from exposed mice as well as in exposed isolated cells were compared. It was found that the dynamics of TNF secretory activity of cells varies depending on the frequency and duration of exposure. The application of millimeter waves induced a nonmonotonous course of the dose-effect curve for TNF changes in macrophages and splenocytes. Alternately, a stimulation and a decrease in TNF production were observed following the application of millimeter waves. On the contrary, centimeter waves provoked an activation in cytokine production. It is proposed that, in contrast to millimeter waves, the single application of centimeter waves to animals (within 2 to 96 h) or isolated cells (within 0.5 to 2.5 h) induced a much more substantial stimulation of immunity.

The dose dependence of natural killer (NK) cell activity from mouse spleen upon action of low-intensity millimeter waves in the exposure range from 5 to 96 hours was studied. It has found an increase of NK activity by 24 hours posttreatment that returned to normal level in a day after the cessation of the irradiation. Also the stimulation of isolated NK cell activity after millimeter waves treatment within 1 hour was revealed.

It was found that single total-body exposure to electromagnetic centimeter waves (8.15-18 GHz, 1 microW/cm2, 5 h) stimulated the proliferation of mouse T and B splenic lymphocytes. The same effects were observed upon in vivo treatment of rats for 5 h with millimeter waves (42.2 GHz, amplitude modulation 10 Hz, 1 microW/cm2). The whole-body irradiation with centimeter or millimeter waves did not cause any significant changes in natural activity of killer cells. The cellular responses induced by the irradiation of isolated animal cells in vitro did not coincide with those revealed after the total-body irradiation of animals. Thus, the in vitro irradiation of natural killer cells to millimeter waves for 1 h increased their cytotoxic activity whereas, after treatment to centimeter waves for the same time, the activity of killer cells did not change. On the contrary, irradiation of T and B lymphocytes with millimeter waves (42.2 GHz, amplitude modulation 10 Hz, 1 microW/cm2, 1 h) suppressed the blasttransformation of cells. The results show a higher immunostimulative potential of centimeter waves as compared to millimeter waves.

The effect of low-intensity centimeter electromagnetic waves (8.15-18 GHz, 1 microW/cm2, 1.5 h daily, 20 days) on the production of tumor necrosis factor, intreleukin-2, and interleukin-3 and the expression of the heat shock protein 72 in healthy and tumor-bearing mice was measured. A significant increase in tumor necrosis factor production and a slight reduction of interleukin-2 concentration were observed after exposure to microwaves; we consider these effects as adaptive response. The interleukin-3 production in healthy mice was not affected by microwaves. Low-intensity centimeter waves induced antitumoral resistance in tumor-bearing mice. Thus, exposure of tumor-bearing mice led to a significant rise in the tumor necrosis factor production and the normalization of both interleukin-2 and interleukin-3 concentration. We assume that the significant immunomodulating effect of low-density centimeter microwaves can be used for immunocorrection and suppression of tumor growth.

It was found that weak magnetic fields (constant 42 microT; variable 0.05 microT; summation of frequencies in the range of 3.58-4.88 Hz) substantially (approximately fourfold) accelerate the hydrolysis of the amyloid beta-protein in aqueous solution. A region of the amyloid beta-protein most sensitive to the action of weak magnetic fields was determined. It is localized between Asp and Ser amino acid residues in positions 7 and 8 of the peptide sequence. It is in this region that the hydrolysis of the molecule of the amyloid beta-protein by the action of magnetic fields predominantly takes place.

The effect of low-level millimeter fractionated radiation on the production of tumor necrosis factor, intreleukin-2, interleukine-3, and nitric oxide and on the activity of natural killer cells and proliferation of T and B lymphocytes in mice was studied. Cell activity was measured in four groups of male Balb/c mice (control, exposed, tumor-bearing unexposed, and exposed tumor-bearing animals) within 30 days of tumoral growth and microwave exposure (42.2 GHz, 10 Hz amplitude modulation, 0.5 microW/cm2, 1.5 h daily). A significant increase in the production of tumor necrosis factor and nitric oxide and in the activity of natural killer cells was observed at the early stage of tumor development; this effect was considered as adaptive response. In healthy mice, millimeter radiation produced both stimulating and immunodepressive effects. The changes were nonmonotonous; as the exposure duration was increased, the stimulating effect became weaker and on day 30 it was not observed. Irradiation of tumor-bearing mice did not induce any significant changes in the activity of cells compared to unirradiated tumor-bearing animals. Moreover, exposure to millimeter waves impaired some characteristics of cell immunity in tumor-bearing mice. It was concluded that low-intensity millimeter waves do not increase the resistance against tumor as it was shown earlier in our experiments with centimeter waves.

The mechanism of interaction of an external magnetic field with liquid was proposed. The statistical integral and configurational contributions for a free energy, entropy and specific heat for the soliton model of bulk knitted structures in a magnetic field were calculated. It was shown that the concentration of solitons depends on the effect of external fields. In the specific case of bulk knitted structures (liquid water without magnetic field), the theoretical data are consistent with experimental. The memory effects in systems with hydrogen bonds in magnetic field was explained in the framework of the continuum soliton concept.

Exposure of deionized water of high purity grade to weak magnetic fields (collinear fields: the constant component 42 +/- 0.1 microT; the alternating component: amplitude 60 +/- 2 nT, frequency 3.7 Hz) for 12 h affects the structure formation in a water-xenon system. This is evidenced by the formation of xenon clathrate crystals a few submicrons and microns in size whereas in initial water solution these crystals were absent. The changes in water properties persist for at least two days after the treatment with magnetic fields. The addition into water of calcium ions at a concentration close to physiological completely eliminates the effect of the formation of submicron and micron crystals of xenon gas hydrates.

The effects of low-density centimeter waves (8.15-18 GHz, 1 microW/cm2, 1 h daily for 14 days; MW) on tumor necrosis factor production in macrophages of mice with different growth rate of a cancer solid model produced after hypodermic injection of Ehrlich carcinoma ascites cells into hind legs were studied. After irradiation, an increase in the concentration of tumor necrosis factor in immunocompetent cells of healthy and, specially, of tumor-bearing animals was observed; and the effect of stimulation was higher upon exposure of mice carrying rapidly growing tumors. We suggest that the significant immunomodulating effect of low-density microwaves can be utilized for tumor growth suppression.

We have studied the effect of weak electromagnetic field on the morphogenesis of the planarian Dugesia tigrina. Regeneration of the pharynx was examined after its amputation. We have determined the rate of the appearance of the food response of a new pharynx. Experimental conditions were varied, such as dose and duration of irradiation, season, and time of irradiation after surgery. The results of experiments conducted with 2966 planarians have shown that weak electromagnetic field has various effects, which appear either as stimulation of regeneration or as its inhibition. In some experiments, there was no effect at all. These differences depend on numerous factors and may be modulated.

A new model of liquid water is proposed, which involves the liquid-crystalline phase, namely, the presence of linearly ordered chains of water molecules and large clusters of these molecules. The presence of linearly ordered chains and clusters in liquid water makes itself evident after the exposure of water to low-frequency electromagnetic radiation. The kinetics of the linearly ordered chains is described by nonlinear excitations (solitons). A hydrodynamic equation describing the behavior of this model system was derived. On the basis of the model, the dimensions of clusters were determined (approximately 600 A). The calculated values of dielectric permeability in the range of low frequencies appeared to be close to their experimentally obtained values. A tenfold increase in the stationary value of dielectric permeability compared with the known value of the dielectric constant in the frequency range of 10(4)-10(6) Hz was predicted. The frequency dependence of dielectric permeability in this range was studied.

Irradiation with electromagnetic waves (8.15-18 GHz, 1 Hz within, 1 microW/cm2) in vivo increases the cytotoxic activity of natural killer cells of rat spleen. In mice exposed for 24-72 h, the activity of natural killer cells increased by 130-150%, the increased level of activity persisting within 24 h after the cessation of treatment. Microwave irradiation of animals in vivo for 3.5 and 5 h, and a short exposure of splenic cells in vitro did not affect the activity of natural killer cells.

It was shown that weak combined static (42 microT) and low-frequency variable (40 nT; 3-5 Hz) magnetic fields change the intensity of intrinsic fluorescence of some proteins (cytochrome c, bovine serum albumin, horseradish peroxidase, alkaline phosphatase). The effect can be interpreted as a change in the conformational state of the protein in water environment by the action of weak magnetic fields. The dynamics of the process, the concentration dependence, the binding of proteins to the fluorescence probe 1,8-ANS after treatment with magnetic fields, the frequency dependence of these reactions, and the dependence of the effect on the presence of the static constituent of the magnetic field were studied. It was shown that the changes in the intrinsic fluorescence of some enzymes (horseradish peroxidase, alkaline phosphatase) are related to changes in their functional activity. It was found that the effect is partially transferred via a solvent (water, 0.01 M NaCl) preliminarily treated with magnetic field. In the solvent, changes in its intrinsic fluorescence by the action of weak magnetic fields were also registered.

The effect of weak direct and alternative magnetic fields adjusted to cyclotron frequencies of ions of polar amino acids leads to a functional inactivation of the recombinant reverse transcriptase of Rous sarcoma virus, which is coupled with the proteolysis of this enzyme.

It was shown that combined action of weak magnetic fields adjusted to cyclotronic frequencies of polar amino acids ions, on aqueous solutions of acidic non-histone protein-inhibitor of DNAase 1 led to proteolysis of this inhibitor. The fragments obtained as a result of proteolysis differ from the whole molecule by amino acid composition and the time of elution from column in case of HPLC.

The possible mechanism of action of weak electric and magnetic fields of extremely low frequency on biomolecules is discussed in terms of the resonance effects on the precession of the ion orbits in a static magnetic field. The proposed model retains the principal merits of the familiar model of Liboff, but is free from the basic shortcomings of the latter.