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1.
The total current of Ca2+ ions through patch-clamped cell membranes was measured while exposing clonal insulin-producing β-cells (RINm5F) to a combination of DC and AC magnetic fields at so-called cyclotron resonance conditions. Previous experimental evidence supports the theory that a resonant interaction between magnetic fields and organisms can exist. This experiment was designed to test one possible site of interaction: channels in the cell membrane. The transport of Ca2+ ions through the protein channels of the plasma membrane did not show any resonant behavior in the frequency range studied. © 1995 Wiley-Liss, Inc. 相似文献
2.
Transient effect of weak electromagnetic fields on calcium ion concentration in Arabidopsis thaliana
Background
Weak magnetic and electromagnetic fields can influence physiological processes in animals, plants and microorganisms, but the underlying way of perception is poorly understood. The ion cyclotron resonance is one of the discussed mechanisms, predicting biological effects for definite frequencies and intensities of electromagnetic fields possibly by affecting the physiological availability of small ions. Above all an influence on Calcium, which is crucial for many life processes, is in the focus of interest. We show that in Arabidopsis thaliana, changes in Ca2+-concentrations can be induced by combinations of magnetic and electromagnetic fields that match Ca2+-ion cyclotron resonance conditions. 相似文献3.
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
4.
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
5.
We seek to extend the recent suggestion that classical cyclotron resonance of biologically important ions is implicated in weak electromagnetic field-cell interactions. The motion of charged particles in a constant magnetic field and periodic electric field is examined under the simplifying assumption of no damping. Each of the nine terms of the relative dielectric tensor is found to have a dependence on functions that include the factor (omega 2 - omega 2B)-1, where omega B is the gyrofrequency. We also find a plasmalike decomposition of the electric field into oppositely rotating components that could conceivably act to drive oppositely charged ions in the same direction through helical membrane channels. For weak low-frequency magnetic fields, an additional feature arises, namely, periodic reinforcement of the resonance condition with intervals of the order of tens of msec for biological ions such as Li+, Na+, and K+. 相似文献
6.
A helitetrahedral model has been proposed to help explain reports of low-frequency oscillations in pure water following electromagnetic excitation at the hydronium ion cyclotron resonance frequency. The Lorentz force and the intrinsic structure constrain the motion of the H3O+ ion so that it enjoys a unique form of proton-hopping, one whose path is helical. This model may also explain the numerous previously observed cyclotron resonance (ICR) biological couplings for cations other than hydronium by merely substituting hydrogen-bonded versions of these for hydronium in the tetrahedral structure. Thus the effectiveness of resonance stimulation in biological systems is explained in terms of the enhanced conductivity and reduced scattering associated with proton-hopping. It is further shown that the addition of charge-balancing hydroxyl ions act to enable oscillatory electric dipole moments that propagate along the helical axis, giving rise to weak power (≈ femtoWatts) radiation patterns. It is conceivable that the radiation associated with this process may play a role in the interactions at the interface between water and living matter. 相似文献
7.
A. V. Timofeev 《Plasma Physics Reports》2014,40(1):1-13
Physical processes determining the excitation of RF electromagnetic fields in a plasma column in a magnetic field are analyzed. The Alfvén resonance plays an important role at frequencies close to the ion cyclotron frequency. It leads to the enhancement of the RF electric field and transformation of Alfvén oscillations with a predominantly transverse polarization of the electric field into lower hybrid ones, which have a significant longitudinal component of the electric field. Lower hybrid oscillations efficiently interact with electrons causing their heating. Difficulties in the implementation of ion cyclotron resonance heating by the magnetic beach method are outlined. The processes considered in this work can be important for the VASIMR plasma engine. 相似文献
8.
Javier García-Sancho Mayte Montero Javier Alvarez Rosalba I. Fonteriz Ana Sanchez 《Bioelectromagnetics》1994,15(6):579-588
We have investigated the effects of sinusoidal electromagnetic fields (EMF) on ion transport (Ca2+, Na+, K+, and H+) in several cell types (red blood cells, thymocytes, Ehrlich ascites tumor cells, and HL60 and U937 human leukemia cells). The effects on the uptake of radioactive tracers as well as on the cytosolic Ca2+ concentration ([Ca2+]i), the intracellular pH (pHi), and the transmembrane potentsial (TMP) were studied. Exposure to EMF at 50 Hz and 100–2000 μT (rms) had no significant effects on any of these parameters. Exposure to EMF of 20–1200 μT (rms) at the estimated cyclotron magnetic resonance frequencies for the respective ions had no significant effects except for a 12–32% increase of the uptake of 42K within a window at 14.5–15.5 Hz and 100–200 μT (rms), which was found in U937 and Ehrlich cells but not in the other cell types. © 1994 Wiley-Liss, Inc. 相似文献
9.
Liboff AR 《Electromagnetic biology and medicine》2007,26(4):315-325
Based on decades of experimental evidence an excellent argument can be made for the existence of a fundamental functional relationship between living systems and electromagnetic fields. We have previously hypothesized that this relationship can be expressed in terms of a field vector whose source is the distribution of electric polarization within the system and which has both a phylogenetic and ontogenetic time dependence. Ion cyclotron resonance (ICR)-like magnetic signals have resulted in physiologic changes in many in vitro and in vivo model systems and have been applied medically with success to bone repair and spinal fusion. This type of local ICR-like therapy has recently been broadened into a holistic application following the remarkable discovery that the whole-body bioimpedance is sharply dependent on ICR signals. We relate this observation to the integrated electric polarization vector, in turn a measure of the double layer charge distribution at the cell membrane. This discovery, already being applied to a number of clinical problems, lends strong support to the concept of an overarching electromagnetic framework for living systems. 相似文献
10.
Characteristic features of the propagation of electromagnetic electron cyclotron waves in the vicinity of the electron cyclotron
resonance surface are investigated both analytically and numerically with allowance for variation in the magnetic field strength
and a corresponding variation in the magnetic field direction. It is demonstrated that variation in the magnetic field direction
can qualitatively change the wave propagation pattern and can markedly affect the efficiency of electron cyclotron resonance
plasma heating in an axisymmetric magnetic trap. 相似文献
11.
The incorporation of 45Ca in mixed human lymphocytes was measured following one-hour exposures of the cells to combined steady and periodic magnetic fields designed to probe for cyclotron resonance response in calcium incorporation. Measurements were made as a function of magnetic field frequency, up to 30 Hz, and as a function of magnetic field amplitude, up to 1.5 x 10(-4) Trms. The amplitude measurements demonstrated that the relative 45Ca uptake at resonance follows different mechanisms of interaction above and below 0.2 x 10(-4) Trms. After adjusting the magnetic field configuration for maximum incorporation, we then determined the effects of the calcium influx blocker nifedipine on 45Ca incorporation, with and without simultaneous exposure to this specific magnetic field combination. The presence of nifedipine in both unexposed and exposed cell suspensions resulted in decreased 45Ca uptake, presumably through the slow inward calcium channels. Evidence was found suggesting that nifedipine acts antagonistically to the 45Ca cyclotron resonance tuning signal. 相似文献
12.
Alexander Pazur 《Electromagnetic biology and medicine》2018,37(2):100-113
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
13.
Recent observations of low-frequency electromagnetic oscillations in water suggest an inductive structural component. Accordingly, we assume a helical basis enabling us to model water as an LC tuned oscillator. A proposed tetrahedral structure consisting of three water molecules and one hydronium ion is incorporated into the Boerdijk–Coxeter tetrahelix to form long water chains that are shown to have resonance frequencies consistent with observation. This model also serves to explain separately reported claims of ion cyclotron resonance of hydronium ions, in that the tetrahelix provides a built-in path for helical proton-hopping. 相似文献
14.
《Biochimica et Biophysica Acta (BBA)/General Subjects》2001,1526(3):269-276
The effects of magnetic fields of extremely low frequency (ELF, 21 μT r.m.s.) on cells of different Escherichia coli K12 strains and human lymphocytes were studied by the method of anomalous viscosity time dependence (AVTD). Within the frequency range of 6–24 Hz, two resonance-type frequency windows with maximal effects at 9 Hz and 16 Hz were observed in response of GE499 strain. Only one frequency window with maximum effect at 8.5 Hz was found for GE500 cells. These data along with previously obtained for two other E. coli strains, AB1157 and EMG2, indicate that frequency windows are dependent on genotype of cells exposed to ELF. Resonance-type effects of ELF were also observed in human lymphocytes in frequency windows around 8 and 58 Hz. These ELF effects differed significantly between studied donors, but were well reproducible in independent experiments with lymphocytes from the same donors. The frequency windows in response of E. coli strains and human lymphocytes to ELF significantly overlapped suggesting that the same targets may be involved in this response. We compared the frequency windows with predictions based on the ion cyclotron resonance (ICR) model and the magnetic parametric resonance model. These models predicted effects of ELF magnetic fields at the ‘cyclotron’ frequencies of some ions of biological relevance. According to the ICR model, ELF effects should be also observed at harmonics of cyclotron frequencies and, contrary, parametric resonance model predicted effects at subharmonics. While we observed coincidence of each experimental resonance frequency with predictions of one of these two models, all experimentally defined effective frequency windows were in good agreement with relatively narrow frequency ranges of both harmonics and subharmonics for natural isotopes of Na, K, Ca, Mg, and Zn ions. The experimental data support idea that both harmonics and subharmonics of several biologically important ions are involved in frequency-dependent ELF effects in cells of different types. 相似文献
15.
One of the main problems of bioelectromagnetics - the unbelievable narrow resonance peaks at the cyclotron frequency of the alternating magnetic field - was considered. Modern electrodynamics of condensed matter clearly brings out that the reason of this phenomenon is extremely low viscosity within coherence domains of aqueous electrolytic solutions. The electrochemical model of action of combined static and alternating magnetic fields on aqueous solutions of amino acids is proposed. The possibility of arising a succession of changes in ionic forms in these processes was revealed. The dipole ions (zwitterions) together with water molecules electrostatically forming joint groups in the solution, create favorable conditions for arising mixed coherence domains there. Simultaneously with evolution of the coherent processes in these domains, the amino acid zwitterions are transforming into the usual ionic form, fit for cyclotron resonance. The development of cyclotron resonance under action of combined magnetic fields increases the ion kinetic energy, and the ions leave the domains for the incoherent component of the solution according to Del Giudice pattern (Comisso et al., 2006; Del Giudice et al., 2002), creating the peak current through the solution. Then the ions are transforming little by little into zwitterionic form again; after that, the solution becomes ready to react on exposure of magnetic fields again. The possibilities for formation of coherence domains composed of water molecules together with peptide molecules or protein ones are discussed. 相似文献
16.
Calcium cyclotron resonance and diatom mobility 总被引:5,自引:0,他引:5
The hypothesis that movement of biological ions may be predicted by cyclotron resonance theory applied to cell membranes is tested in these experiments. Diatoms (Amphora coffeaeformis) were chosen as the biosystem since they move or don't move, depending on how much calcium is transported across the membrane. The experiments demonstrate that a particular ion (calcium) is apparently moved across the cell membrane in response to the DC and AC values of magnetic flux densities (B) and the frequency derived from the cyclotron resonance theory. A clear resonance is shown and a rather sharp frequency response curve is demonstrated. The experiments also show a dose response as the AC value of the flux density is varied, and that odd harmonics of the basic cyclotron frequency are also effective. 相似文献
17.
J I Jacobson 《Journal of theoretical biology》1991,149(1):97-119
A testable theoretical model for the mechanism of magneto-therapy is presented. The theory delineated is the equation mc2 = Bvl coulomb which sets in dual resonance gravitational and electromagnetic potentials. This proposed unification of Einstein's gravity and Maxwell's electromagnetism is designated Jacobson's resonance and is a general expression of Zeeman and cyclotron resonance. The application of this theory involves the utilization of exogenously sourced very weak magnetic fields on the order of magnitude 10(-8) gauss to reorient the atomic crystal lattice structures of genomic magnetic domains. Examples of genomic magnetic domains are homeoboxes and oncogenes and associated structures like peptide hormone trophic factors. Various phenomena are also analyzed in terms of how they may relate to biological systems such as solitons, phonons, cyclotron resonance, the piezoelectric effect, the fractional quantum Hall effect, string theory, and biologically closed electric circuits. The potential of magneto-therapy in the treatment of various genomic and associated disorders is explored. The ultimate question "Can an oncogene be electromagnetically induced into becoming a structurally homologous normal gene?" is posed. 相似文献
18.
The effects of magnetic fields of extremely low frequency (ELF, 21 microT r.m.s.) on cells of different Escherichia coli K12 strains and human lymphocytes were studied by the method of anomalous viscosity time dependence (AVTD). Within the frequency range of 6-24 Hz, two resonance-type frequency windows with maximal effects at 9 Hz and 16 Hz were observed in response of GE499 strain. Only one frequency window with maximum effect at 8.5 Hz was found for GE500 cells. These data along with previously obtained for two other E. coli strains, AB1157 and EMG2, indicate that frequency windows are dependent on genotype of cells exposed to ELF. Resonance-type effects of ELF were also observed in human lymphocytes in frequency windows around 8 and 58 Hz. These ELF effects differed significantly between studied donors, but were well reproducible in independent experiments with lymphocytes from the same donors. The frequency windows in response of E. coli strains and human lymphocytes to ELF significantly overlapped suggesting that the same targets may be involved in this response. We compared the frequency windows with predictions based on the ion cyclotron resonance (ICR) model and the magnetic parametric resonance model. These models predicted effects of ELF magnetic fields at the 'cyclotron' frequencies of some ions of biological relevance. According to the ICR model, ELF effects should be also observed at harmonics of cyclotron frequencies and, contrary, parametric resonance model predicted effects at subharmonics. While we observed coincidence of each experimental resonance frequency with predictions of one of these two models, all experimentally defined effective frequency windows were in good agreement with relatively narrow frequency ranges of both harmonics and subharmonics for natural isotopes of Na, K, Ca, Mg, and Zn ions. The experimental data support idea that both harmonics and subharmonics of several biologically important ions are involved in frequency-dependent ELF effects in cells of different types. 相似文献
19.
《Electromagnetic biology and medicine》2013,32(4):370-375
AbstractThere 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
20.
It is shown that, under the influence of magnetic field, rotational moments of the same direction appear for all charged particles having the same sign of their charge and freely moving in a thermal fluctuational electromagnetic field in a diamagnetic condensed matter. The magnitude of this rotational moment is proportional to the thermal energy kT and can be substantially increased when the conditions for cyclotron resonance are satisfied. The moments of positively charged particles are directed oppositely to the vector of the magnetic field induction. The so-called "kT problem" has been solved. The evidence for magnetosensitivity is the appearance of rotational moments acting on the particles from the thermal field in the presence of an external magnetic field as a small factor. 相似文献