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1.
Current peaks have been observed and measured in electrolytic ionic current of L-glutamic acid aqueous solutions at room temperature, in static magnetic fields of 20, 40, and 60 muT flux densities, with a superimposed extremely low-frequency, (1/10) Hz, alternating magnetic field flux density of 40 nT. The distributions of the peaks have mean values centered at the cyclotron resonance frequency of the singly charged L-glutamic acid ion molecular mass in the corresponding static field. Amplitudes and widths of the peaks are compared and analyzed to extract their correlation. The results can be considered a contribution to the understanding of the experimental phenomenology in low-frequency electromagnetic fields on ionic currents of L-glutamic amino acid aqueous solutions. The results can be of interest in the studies on the interaction of the electromagnetic fields with some structural neurotransmitters in cellular medium.  相似文献   

2.
Weak magnetic and electromagnetic fields affect physiological processes in animals, plants, and microorganisms. Ion cyclotron resonance (ICR) is discussed as one of the sensitive mechanisms, which enable perception of the geomagnetic field and its orientation. Numerous biological effects are observed involving several small ions, showing windows of predicted frequencies and intensities. The pioneering work of Guiliano Preparata and Emilio Del Giudice using quantum electrodynamics showed that spontaneously originating coherent regions in water facilitate ICR effects at incoherent water phase boundaries. Here we examine the ICR response of the calcium ion (Ca2+), crucial for many life processes. We use an aqueous solution containing the biologically ubiquitous membrane lipid L-α-phosphatidylcholine that serves as a biomimetic proxy for dynamic light scattering (DLS) and nonlinear dielectric spectroscopy (NLDS) measurements. One notable result is that this system approaches a new equilibrium upon addition of calcium by means of the oscillatory Belousov–Zhabotinsky chemical reaction, oscillations are significantly reduced under Ca2+ ICR application. Secondly an “oscillator” of calcium ions appears to be able to itself couple coherently and predictably to large-scale coherent regions in water. This system appears able to regulate ion fluxes in response to very weak environmental electromagnetic fields.  相似文献   

3.
A current peak has been observed and measured in ionic electrolytic current of a glutamic acid aqueous solution, placed in a static magnetic field of flux density of 40 microT, with a superimposed low-frequency alternating magnetic field of flux density of 40 nT. The peak occurs at the frequency of the cyclotronic resonance of the molecular mass of a single charged glutamic acid ion, placed in a magnetic flux density equal to that of the static field. The amplitude of the current peak is about 30% of the background electrolytic current. Qualitative considerations and a listing of unsolved problems related to the phenomenology are given. The result is the first contribution to the study we have undertaken on the effects of low-frequency alternating electromagnetic fields on the ionic current of amino acid aqueous solutions which are the basic structural units of the proteins.  相似文献   

4.
In this study we show a reproduction of the Zhadin experiment, which consists of the transient increase of the electrolytic current flow across an aqueous solution of L-arginine and L-glutamic acid induced by a proper low frequency alternating magnetic field superimposed to a static magnetic field of higher strength. We have identified the mechanisms that were at the origin of the so-far poor reproducibility of the above effect: the state of polarization of the electrode turned out to be a key parameter. The electrochemical investigation of the system shows that the observed phenomenon involves the transitory activation of the anode due to ion cyclotron frequency effect, followed again by anode passivation due to the adsorption of amino acid and its oxidation products. The likely occurrence of similar ion cyclotron resonance (ICR) phenomena at biological membranes, the implications on ion circulation in living matter, and the consequent biological impact of environmental magnetic fields are eventually discussed.  相似文献   

5.
Combined parallel static and alternating magnetic fields cause a rapid change in the ionic current flowing through an aqueous glutamic acid solution when the alternating field frequency is equal to the cyclotron frequency. The current peak is 20-30% of the background direct current. The peak is observed with slow sweep in the alternating magnetic field frequency from 1 Hz-10 Hz. Only one resonance peak in the current is observed in this frequency range. The frequency corresponding to the peak is directly proportional to the static magnetic field. The above effect only arises at very small alternating field amplitude in the range from 0.02 μT-0.08 μT. Bioelectromagnetics 19:41–45, 1998. © 1998 Wiley-Liss, Inc.  相似文献   

6.
The fundamental physical mechanisms of resonance action of an extremely weak (40 nT) alternating magnetic field at the cyclotron frequency combined with a weak (40 μT) static magnetic field, on living systems are analyzed in the present work. The experimental effects of such sort of magnetic fields were described in different papers: the very narrow resonant peaks in electrical conductivity of the aqueous solutions in the in vitro experiments and the biomedical in vivo effects on living animals of magnetic fields with frequencies tuned to some amino acids. The existing experimental in vitro data had a good repeatability in different laboratories and countries. Unfortunately, for free ions such sort of effects are absolutely impossible because the dimensions of an ion rotation radius should be measured by meters at room temperature and at very low static magnetic fields used in all the above experiments. Even for bound ions these effects should be also absolutely impossible from the positions of classic physics because of rather high viscosity of biological liquid media (blood plasma, cerebrospinal liquid, cytoplasm). Only modern quantum electrodynamics of condensed media opens the new ways for solving these problems. The proposed article is devoted to analysis of quantum mechanisms of these effects.  相似文献   

7.
A recent experiment on a physical, nonbiological system of ions at room temperature has proved that microscopic ion currents can be induced by applying simultaneously two parallel magnetic fields, one rather weak static field, (-->)B(0) and one much weaker alternating field, (-->) B(ac),[B(ac) approximately 10(-3) B(0)] whose frequency coincides with the cyclotron frequency v = qB(0)/2pim of the selected ion. As a result, ionic bursts lasting up to 20 s and with amplitude up to 10 nA arise. The much larger exchanges of energy induced by thermal agitation (the "kT-problem") appear to play no role whatsoever. We have analyzed this problem in the framework of coherent quantum electrodynamics, reaching the following conclusions: (a) as has been shown in previous articles, water molecules in the liquid and solute ions are involved in their ground state in coherent ordered configurations; (b) ions are able to move without collisions among themselves in the interstices between water coherence domains; (c) because of coherence, ions can follow classical orbits in the magnetic fields. A full quantitative understanding of the experiments is thus reached.  相似文献   

8.
It was shown that preliminary treatment of the protein component (histone H3, protamine sulfate, polyarginine) of a DNA-protein complex with weak combined (42 microT) and low-frequency (3.5-5.0 Hz) alternating (0.06 microT) magnetic fields adjusted formally to the cyclotron resonance of amino acid ions charged under natural conditions leads to substantial changes in complex formation and formation of complexes of a different type than without treatment.  相似文献   

9.
Reports that extremely low-frequency magnetic fields can interfere with normal biological cell function continue to stimulate experimental activity as well as investigations into the possible mechanism of the interaction. The "cyclotron resonance" model of Liboff has been tested by Smith et al. (Bioelectromagnetics 8, 215-227, 1987) using as the biological test system the diatom Amphora coffeiformis. They report enhanced motility of the diatom in response to a low-frequency electromagnetic field tuned to the cyclotron resonance condition for calcium ions. We report here an attempt to reproduce their results. Following their protocol diatoms were seeded onto agar plates containing varying amounts of calcium and exposed to colinear DC and AC magnetic fields tuned to the cyclotron resonant condition for frequencies of 16, 30, and 60 Hz. The fractional motility was compared with that of control plates seeded at the same time from the same culture. We find no evidence of a cyclotron resonance effect.  相似文献   

10.
BACKGROUND: Previous reports indicate altered metabolism and enzyme kinetics for various organisms, as well as changes of neuronal functions and behaviour of higher animals, when they were exposed to specific combinations of weak static and alternating low frequency electromagnetic fields. Field strengths and frequencies, as well as properties of involved ions were related by a linear equation, known as the formula of ion cyclotron resonance (ICR, abbreviation mentioned first by Liboff). Under certain conditions already a aqueous solution of the amino acid and neurotransmitter glutamate shows this effect. METHODS: An aqueous solution of glutamate was exposed to a combination of a static magnetic field of 40 muT and a sinusoidal electromagnetic magnetic field (EMF) with variable frequency (2-7 Hz) and an amplitude of 50 nT. The electric conductivity and dielectric properties of the solution were investigated by voltammetric techniques in combination with non linear dielectric spectroscopy (NLDS), which allow the examination of the dielectric properties of macromolecules and molecular aggregates in water. The experiments target to elucidate the biological relevance of the observed EMF effect on molecular level. RESULTS: An ion cyclotron resonance (ICR) effect of glutamate previously reported by the Fesenko laboratory 1998 could be confirmed. Frequency resolution of the sample currents was possible by NLDS techniques. The spectrum peaks when the conditions for ion cyclotron resonance (ICR) of glutamate are matched. Furthermore, the NLDS spectra are different under ICR- and non-ICR conditions: NLDS measurements with rising control voltages from 100-1100 mV show different courses of the intensities of the low order harmonics, which could possibly indicate "intensity windows". Furthermore, the observed magnetic field effects are pH dependent with a narrow optimum around pH 2.85. CONCLUSIONS: Data will be discussed in the context with recent published models for the interaction of weak EMF with biological matter including ICR. A medical and health relevant aspect of such sensitive effects might be given insofar, because electromagnetic conditions for it occur at many occasions in our electromagnetic all day environment, concerning ion involvement of different biochemical pathways.  相似文献   

11.
It was shown that water with additions of Ca2+, Na+, K+ and Cl- ions preliminarily treated with weak combined constant (42 microT) and low-frequency alternating (0.06 microT) magnetic fields affects the intrinsic fluorescence of bovine serum albumin, the magnitude of the effect being dependent on the frequency of the alternating field and ionic composition of the aqueous salt solution. A practically complete transfer of the effect through a small portion of the solution treated with magnetic fields was revealed. It was also found that after magnetic treatment, the solution contains a rather large (molecular mass 700-900 D) and stable molecular associate, which possesses, at least partially, the properties and characteristics inherent in the whole solution that were as acquired as a result of magnetic treatment.  相似文献   

12.
The alga Ankistrodesmus braunii was grown with [14N]nitrate under optimized conditions of a large-scale mass cultivation. 19.7% of the dried algae were isolated as a mixture of amino acids. The 15N-labelled amino acids (15N content up to 98%) were separated by ion exchange chromatography using pyridine acetate gradients. The 15N cotent of the analytically pure amino acid was determined by combined gas-liquid chromatography-mass spectrometry of the trifluoroacetylated methylesters and by emission spectroscopy in the 15N analysator. Using pulse Fourier transform 13C nuclear magnetic resonance, the pH dependence of the 13C-15N coupling constants of Asp, Pro, Ser, Glu, Gly, Ala, Val, Ile and Leu was determined in aqueous solutions. Increasing coupling constants were found with pH and decreasing electron density, respectively. The relation of Binsch et al. (Binsch, G., Lambert, J.B., Roberts, B.W. and Roberts, J.D. (1964) J.Am. Chem. Soc. 86,5564-5570) between the coupling constant and the product of the S-part of the 13C and 15N hybridization SC - SN = 80 - J (13C-45X) fits best in acidic medium. The magnitude of coupling constants correlates well with the electron densities calculated by Del Re et al. (Del Re, G., Pullman, B. and Yonezawa, T. (1963) Biochim. Biophys. Acta 75, 153-182). The recording of 13C nuclear magnetic resonance spectra over the entire pH range revealed no change in the sign of the 13C-15N coupling constants of the amino acids.  相似文献   

13.
Organisms exposed to a combination of weak, parallel static and alternating magnetic fields show a distinct response when the frequency of the alternating component is formally equal to the cyclotron frequencies for Ca2+ or other biologically important ions. It is impossible to explain the observable phenomenon through a magnetoinduced drift of the ions, as the Lorentz force is too small to change ionic movements. In similar conditions, a resonance-like response arises when the alternating field is tuned to the Larmor frequency for nuclear-spin magnetic moments. The mechanism of these phenomena is also still unclear. In this communication, arguments are presented whereby both types of effect can be treated in a unified context, for which the existence of ion-specific magnetic dipoles must be postulated.  相似文献   

14.
In the present work the results of the known investigation of the influence of combined static (40 μT) and alternating (amplitude of 40 nT) parallel magnetic fields on the current through the aqueous solution of glutamic acid, were successfully replicated. Fourteen experiments were carried out by the application of the combined magnetic fields to the solution placed into a Plexiglas reaction vessel at application of static voltage to golden electrodes placed into the solution. Six experiments were carried out by the application of the combined magnetic fields to the solution placed in a Plexiglas reaction vessel, without electrodes, within an electric field, generated by means of a capacitor at the voltage of 27 mV. The frequency of the alternating field was scanned within the bounds of 1.0 Hz including the cyclotron frequency corresponding to a glutamic acid ion and to the applied static magnetic field. In this study the prominent peaks with half-width of ~0.5 Hz and with different heights (till 80 nA) were registered at the alternating magnetic field frequency equal to the cyclotron frequency (4.2 Hz). The general reproducibility of the investigated effects was 70% among the all solutions studied by us and they arose usually after 40–60 min. after preparation of the solution. In some made-up solutions the appearance of instability in the registered current was noted in 30–45 min after the solution preparation. This instability endured for 20–40 min. At the end of such instability period the effects of combined fields action appeared practically every time. The possible mechanisms of revealed effects were discussed on the basis of modern quantum electrodynamics.  相似文献   

15.
Kinetics of channelized membrane ions in magnetic fields   总被引:5,自引:0,他引:5  
The cyclotron resonance model for channel ion transport in weak magnetic fields is extended to include damping losses. The conductivity tensor is obtained for different electric field configurations, including the circuital field E phi normal to the channel axis. The conductivity behavior close to the cyclotron resonance frequency omega c is compared to existing Ca2+-efflux data in the literature. A collision time of .023 s results from this comparison under the assumption that K+ ions are transiting in a 0.35 G field. We estimate a mean kinetic energy of 3.5 eV for this ion at resonance. This model leads to discrete modes of vibration (eigenfrequencies) in the ion-lattice interaction, such that omega n = n omega c. The presence of such harmonics is compatible with recent results by Blackman et al. [1985b] and McLeod et al. [1986] with the interesting exception that even modes do not appear in their observations, whereas the present model has no restriction on n. This harmonic formalism is also consistent with another reported phenomenon, that of quantized multiple conductances in single patch-clamped channels.  相似文献   

16.
Although considerable experimental evidence now exists to indicate that low-frequency magnetic fileds influence living cells, the mode of coupling remains a mystery. We propose a radical new model for electromagnetic interactions with cells, one resulting from a cyclotron resonance mechanism attached to ions moving through transmembrane channels. It is shown that the cyclotron resonance condition on such ions readily leads to a predicted ELF-coupling at geomagnetic levels. This model quantitatively explains the results reported by Blackman et al. (1984), identifying the focus of magnetic interaction in these experiments as K+ charge carriers. The cyclotron resonance concept is consistent with recent indications showing that many membrane channels have helical configurations. This model is quite testable, can probably be applied to other circulating charge components within the cell and, most important, leads to the feasibility of direct resonant electromagnetic energy transfer to selected compartments of the cell.  相似文献   

17.
Abstract

There is an ongoing question regarding the structure forming capabilities of water at ambient temperatures. To probe for different structures, we studied effects in pure water following magnetic field exposures corresponding to the ion cyclotron resonance of H3O+. Included were measurements of conductivity and pH. We find that under ion cyclotron resonance (ICR) stimulation, water undergoes a transition to a form that is hydroxonium-like, with the subsequent emission of a transient 48.5?Hz magnetic signal, in the absence of any other measurable field. Our results indicate that hydronium resonance stimulation alters the structure of water, enhancing the concentration of EZ-water. These results are not only consistent with Del Giudice's model of electromagnetically coherent domains, but they can also be interpreted to show that these domains exist in quantized spin states.  相似文献   

18.
We investigated the effects of weak combined magnetic fields (MFs) produced by superimposing a constant MF (in the range 30 - 150 µT) and an alternating MF (100 or 200 nT) on cytokine production in healthy Balb/C male mice exposed 2 h daily for 14 days. The alternating magnetic field was a sum of several frequencies (ranging from 2.5 - 17.5 Hz). The frequencies of the alternating magnetic field were calculated formally based on the cyclotron resonance of ions of free amino acids (glutamic and aspartic acids, arginine, lysine, histidine, and tyrosine). The selection of different intensity and frequency combinations of constant and alternating magnetic fields was performed to find the optimal characteristics for cytokine production stimulation in immune cells. MF with a constant component of 60 μT and an alternating component of 100 nT, which was a sum of six frequencies (from 5 to 7 Hz), was found to stimulate the production of tumor necrosis factor-α, interferon-gamma, interleukin-2, and interleukin-3 in healthy mouse cells and induce cytokine accumulation in blood plasma. Then, we studied the effect of this MF on tumor-bearing mice with solid tumors induced by Ehrlich ascite carcinoma cells by observing tumor development processes, including tumor size, mouse survival rate, and average lifespan. Tumor-bearing mice exposed to a combined constant magnetic field of 60 μT and an alternating magnetic field of 100 nT containing six frequencies showed a strong suppression of tumor growth with an increase in survival rate and enhancement of average lifespan.  相似文献   

19.
The action of combined parallel static (DC) and alternating (AC) magnetic fields at the cyclotron frequencies for different biologically active ions, specifically, calcium, sodium, potassium, chlorine, magnesium and lithium, on rat behavior in the "open field" were investigated. It was shown that the DC and AC fields at the calcium cyclotron frequency lower the locomotor and exploratory activity of the rats, whereas action of the fields at the magnesium cyclotron frequency enhances these forms of behavioral activity. The effects were qualitatively alike at the weak (50 microT) and relatively strong (500 microT) DC fields with proportional changes in the frequencies and amplitudes of the AC fields. Statistically significant effects of cyclotron frequencies for other ions studied were not observed.  相似文献   

20.
An elementary model consisting of one charged particle in a viscous medium exposed to weak ac-dc low-frequency magnetic fields is analyzed to identify and explain the fundamental characteristics of the physical mechanisms that result in a resonance response, which is similar to the familiar cyclotron resonance. The model predicts both frequency and amplitude windows, which are explained in terms of synchronization of the particle with electric fields. Although extrapolation of model results to biological systems is limited by the elementary nature of the model, the model results indicate that observed resonant responses by others of biological systems to ac-dc magnetic fields are probably not due to resonant response of ions in solution, since the model predicts that no resonant response is possible unless the viscous damping is very low, many orders of magnitude lower than the viscous damping of ions in solution.  相似文献   

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