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1.
Int J Biometeorol ; 65(1): 31-44, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33236243

RESUMO

Atmospheric electric fields (AEFs) are produced by both natural processes and electrical infrastructure and are increasingly recognized to influence and interfere with various organisms and biological processes, including human well-being. Atmospheric electric fields, in particular electromagnetic fields (EMFs), currently attract a lot of scientific attention due to emerging technologies such as 5G and satellite internet. However, a broader retrospective analysis of available data for both natural and artificial AEFs and EMFs is hampered due to a lack of a semantic approach, preventing data sharing and advancing our understanding of its intrinsic links. Therefore, here we create an ontology (ENET_Ont) for existing (big) data on AEFs within the context of biological systems that is derived from different disciplines that are distributed over many databases. Establishing an environment for data sharing provided by the proposed ontology approach will increase the value of existing data and facilitate reusability for other communities, especially those focusing on public health, ecology, environmental health, biology, climatology as well as bioinformatics.


Assuntos
Eletricidade , Campos Eletromagnéticos , Humanos , Disseminação de Informação , Estudos Retrospectivos , Semântica
2.
Phys Rev E ; 96(1-1): 012404, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29347215

RESUMO

Microtubules provide the mechanical force required for chromosome separation during mitosis. However, little is known about the dynamic (high-frequency) mechanical properties of microtubules. Here, we theoretically propose to control the vibrations of a doubly clamped microtubule by tip electrodes and to detect its motion via the optomechanical coupling between the vibrational modes of the microtubule and an optical cavity. In the presence of a red-detuned strong pump laser, this coupling leads to optomechanical-induced transparency of an optical probe field, which can be detected with state-of-the art technology. The center frequency and line width of the transparency peak give the resonance frequency and damping rate of the microtubule, respectively, while the height of the peak reveals information about the microtubule-cavity field coupling. Our method opens the new possibilities to gain information about the physical properties of microtubules, which will enhance our capability to design physical cancer treatment protocols as alternatives to chemotherapeutic drugs.


Assuntos
Microtúbulos , Nanotecnologia , Dispositivos Ópticos , Vibração , Fenômenos Biomecânicos , Elasticidade , Desenho de Equipamento , Lasers , Microtúbulos/química , Microtúbulos/metabolismo , Modelos Biológicos
3.
Biosystems ; 109(3): 356-66, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22750075

RESUMO

Eigenmodes of the spherical and ellipsoidal dielectric electromagnetic resonator have been analysed. The sizes and shape of the resonators have been chosen to represent the shape of the interphase and dividing animal cell. Electromagnetic modes that have shape exactly suitable for positioning of the sufficiently large organelles in cell (centrosome, nucleus) have been identified. We analysed direction and magnitude of dielectrophoretic force exerted on large organelles by electric field of the modes. We found that the TM(1m1) mode in spherical resonator acts by centripetal force which drags the large organelles which have higher permittivity than the cytosol to the center of the cell. TM-kind of mode in the ellipsoidal resonator acts by force on large polarizable organelles in a direction that corresponds to the movement of the centrosomes (also nucleus) observed during the cell division, i.e. to the foci of the ellipsoidal cell. Minimal required force (10(-16) N), gradient of squared electric field and corresponding energy (10(-16) J) of the mode have been calculated to have biological significance within the periods on the order of time required for cell division. Minimal required energy of the mode, in order to have biological significance, can be lower in the case of resonance of organelle with the field of the cellular resonator mode. In case of sufficient energy in the biologically relevant mode, electromagnetic field of the mode will act as a positioning or steering mechanism for centrosome and nucleus in the cell, thus contribute to the spatial and dynamical self-organization in biological systems.


Assuntos
Ciclo Celular/fisiologia , Forma Celular/fisiologia , Células/citologia , Fenômenos Eletromagnéticos , Modelos Biológicos , Organelas/fisiologia , Animais
4.
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
5.
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
6.
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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