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1.
Prague Med Rep ; 113(2): 81-94, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22691280

RESUMO

Physical processes in living cells were not taken into consideration among the essentials of biological activity, regardless of the fact that they establish a state far from thermodynamic equilibrium. In biological system chemical energy is transformed into the work of physical forces for various biological functions. The energy transformation pathway is very likely connected with generation of the endogenous electrodynamic field as suggested by experimentally proved electrodynamic activity of biological systems connected with mitochondrial and microtubule functions. Besides production of ATP and GTP (adenosine and guanosine triphosphate) mitochondria form a proton space charge layer, strong static electric field, and water ordering around them in cytosol - that are necessary conditions for generation of coherent electrodynamic field by microtubules. Electrodynamic forces are of a long-range nature in comparison with bond and cohesive forces. Mitochondrial dysfunction leads to disturbances of the electromagnetic field; its power and coherence may be diminished, and frequency spectrum altered. Consequently, defective electrodynamic interaction forces between cancer and healthy cells may result in local invasion of cancer cells. Further deformation of interaction forces connected with experimentally disclosed spatial disarrangement of the cytoskeleton and disordered electrodynamic field condition metastatic process. Cancer therapeutic strategy targeting mitochondria may restore normal physiological functions of mitochondria and open the apoptotic pathway. Apoptosis of too much damaged cancer cells was observed. Considerable experience with DCA (dichloroacetate) cancer treatment in humans was accumulated. Clinical trials should assess DCA therapeutic potential and collect data for development of novel more effective drugs for mitochondrial restoration of various cancers.


Assuntos
Transformação Celular Neoplásica/metabolismo , Mitocôndrias/metabolismo , Trifosfato de Adenosina/metabolismo , Ácido Dicloroacético/uso terapêutico , Fenômenos Eletrofisiológicos , Metabolismo Energético , Guanosina Trifosfato/metabolismo , Humanos , Microtúbulos/metabolismo , Microtúbulos/fisiologia , Mitocôndrias/fisiologia , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo
2.
J Theor Biol ; 286(1): 31-40, 2011 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-21782830

RESUMO

Microtubules are important structures in the cytoskeleton, which organizes the cell. Since microtubules are electrically polar, certain microtubule normal vibration modes efficiently generate oscillating electric field. This oscillating field may be important for the intracellular organization and intercellular interaction. There are experiments which indicate electrodynamic activity of variety of cells in the frequency region from kHz to GHz, expecting the microtubules to be the source of this activity. In this paper, results from the calculation of intensity of electric field and of radiated electromagnetic power from the whole cellular microtubule network are presented. The subunits of microtubule (tubulin heterodimers) are approximated by elementary electric dipoles. Mechanical oscillation of microtubule is represented by the spatial function which modulates the dipole moment of subunits. The field around oscillating microtubules is calculated as a vector superposition of contributions from all modulated elementary electric dipoles which comprise the cellular microtubule network. The electromagnetic radiation and field characteristics of the whole cellular microtubule network have not been theoretically analyzed before. For the perspective experimental studies, the results indicate that macroscopic detection system (antenna) is not suitable for measurement of cellular electrodynamic activity in the radiofrequency region since the radiation rate from single cells is very low (lower than 10⁻²° W). Low noise nanoscopic detection methods with high spatial resolution which enable measurement in the cell vicinity are desirable in order to measure cellular electrodynamic activity reliably.


Assuntos
Campos Eletromagnéticos , Microtúbulos/fisiologia , Modelos Biológicos , Animais , Relógios Biológicos/fisiologia , Membrana Celular/fisiologia , Polaridade Celular/fisiologia , Centrossomo/fisiologia , Potenciais da Membrana/fisiologia , Vibração
3.
Biosystems ; 100(2): 122-31, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20178826

RESUMO

Microtubules are electrically polar structures fulfilling prerequisites for generation of oscillatory electric field in the kHz to GHz region. Energy supply for excitation of elasto-electrical vibrations in microtubules may be provided from GTP-hydrolysis; motor protein-microtubule interactions; and energy efflux from mitochondria. We calculated electric field generated by axial longitudinal vibration modes of microtubules for random, and coherent excitation. In case of coherent excitation of vibrations, the electric field intensity is highest at the end of microtubule. The dielectrophoretic force exerted by electric field on the surrounding molecules will influence the kinetics of microtubule polymerization via change in the probability of the transport of charge and mass particles. The electric field generated by vibrations of electrically polar cellular structures is expected to play an important role in biological self-organization.


Assuntos
Polaridade Celular/fisiologia , Campos Eletromagnéticos , Células Eucarióticas/fisiologia , Microtúbulos/fisiologia , Vibração , Relógios Biológicos/fisiologia , Distribuição Aleatória , Fermento Seco
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