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1.
Georgian Med News ; (321): 111-115, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35000918

RESUMO

Prostate biopsy is considered to be one of the most aggressive and invasive methods in the diagnosis of prostate cancer. The researchers' efforts are aimed at using alternative and less invasive methods to manifest this disease at an early stage.The authors propose infrared radiation as a method of such research, which, as studies have shown, is characterized by different permeability to tumorous, healthy and hyperplastic prostate tissue, in particular, the more damaged the prostate tissue, the lower its degree of permeability.Experimentally determined that the highest permeability was found in the wavelength range 840-860 nm. It has been found that cancerous, non-cancerous and healthy prostate tissues are characterized by different permeability to infrared radiation. Healthy tissue has been shown to have the highest permeability to infrared radiation. Cancerous tissue permeability is much lower than that of healthy tissue. Prostate tissue permeability with benign hyperplasia is between the permeability of healthy and tumor tissues.Infrared beam transmittance control can be performed by adjusting the radiation intensity of the emitting source. Dependence of permeability on tissue thickness is linear for healthy tissue and sharply non-linear for tumor tissue.


Assuntos
Próstata , Neoplasias da Próstata , Biópsia , Humanos , Raios Infravermelhos , Masculino , Permeabilidade , Próstata/diagnóstico por imagem , Neoplasias da Próstata/radioterapia
2.
Electromagn Biol Med ; 38(4): 297-306, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31303069

RESUMO

The human head and hand being in the near-field zone of a mobile phone antenna can drastically influence the antenna matching with free space. The goal of the presented research is to study this phenomenon on an inhomogeneous human model for different relative positions and distances of hand and fingers when using a mobile phone. The only safety criteria commonly used to estimate RF exposure impact on humans is the specific absorption rate (SAR). Its limits are determined by the Federal Communication Commission (FCC) in the USA and the International Commission on Non-Ionizing Radiation Protection (ICNIRP) in Europe. The maximal values of SAR for a mobile handset are determined for each model by the manufacturer. In this paper, it is shown that the peak values provided by the manufacturers and their understanding may need refinement. It is almost impossible to consider all parameters, such as the dependence of SAR on antenna communication matching, with a variety of shapes and forms and other details during physical measurements or numerical estimation. The premise for such assumptions is based on the analysis of S11 dependency on the exposure scenario and the fact that the Automatic Gain Control (AGC) increases power when the signal strength at the base station drops.


Assuntos
Telefone Celular , Dedos , Imagens de Fantasmas , Campos Eletromagnéticos/efeitos adversos , Dedos/efeitos da radiação , Mãos/efeitos da radiação , Humanos , Doses de Radiação , Ondas de Rádio/efeitos adversos
3.
Electromagn Biol Med ; 33(1): 18-20, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23730820

RESUMO

Penetration of near infrared radiation (NIR) through biological tissues (human wrist, muscle and skin of hen, muscle of mollusk) was studied. The possibilities of visualizing various objects within biological tissues were examined. It is found that: (a) it is possible to see small objects with millimeter and sub-millimeter dimensions; and (b) by using NIR rays it is possible to distinguish different parts of small homogeneous biological tissues. NIR can be a possible tool in the near future to visualize millimeter size cancerous outgrowths located inside human body cavities. It will enable diagnosis of cancer at an early stage of development.


Assuntos
Detecção Precoce de Câncer/métodos , Raios Infravermelhos , Imagem Óptica/métodos , Animais , Humanos
4.
Electromagn Biol Med ; 32(1): 48-58, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23046101

RESUMO

During exposure to the cell phone electromagnetic field (EMF), some neurons in the brain at areas of peak specific absorption rate (SAR) absorb more electromagnetic energy than is permitted by existing guidelines. The goal of the present work was to investigate the influence of cell phone-like EMF signal on excitability and memory processes in single neurons. A Transverse Electromagnetic Cell (TEM Cell) was used to expose single neurons of mollusk to the EMF. Finite-Difference Time-Domain (FDTD) method was used for modeling the TEM Cell and the EMF interactions with living nerve ganglion and neurons. Neuron electrophysiology was investigated using standard microelectrode technique. SAR deposited into the single neuron was calculated to be 8.2 W/kg with a temperature increment of 1.21°C. After acute exposure, the threshold of firing of action potentials (AP) was significantly decreased (p ≈ 0.001). Time of habituation to stimulation with the intracellular current injection was increased (p ≈ 0.003). These results indicate that acute exposure to EMF at high SARs impairs the ability of neurons to store information.


Assuntos
Telefone Celular , Moluscos , Neurônios/efeitos da radiação , Ondas de Rádio/efeitos adversos , Absorção , Animais , Campos Eletromagnéticos/efeitos adversos , Neurônios/citologia , Doses de Radiação
5.
Electromagn Biol Med ; 30(3): 170-9, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21861695

RESUMO

The goal of the present work was to explore the influence of commercially available cell phone irradiation on the single neuron excitability and memory processes. A Transverse Electromagnetic Cell (TEM Cell) was used to expose single neurons of mollusk to the electromagnetic field. Finite-Difference Time-Domain (FDTD) method was used for modeling the TEM Cell and the electromagnetic field interactions with living nerve ganglion and neurons. Neuron electrophysiology was investigated using standard microelectrode technique. The specific absorption rate (SAR) deposited into the single neuron was calculated to be 0.63 W/kg with a temperature increment of 0.1°C. After acute exposure, average firing threshold of the action potentials was not changed. However, the average latent period was significantly decreased. This indicates that together with latent period the threshold and the time of habituation might be altered during exposure. However, these alterations are transient and only latent period remains on the changed level.


Assuntos
Telefone Celular , Moluscos/citologia , Moluscos/efeitos da radiação , Neurônios/efeitos da radiação , Ondas de Rádio/efeitos adversos , Potenciais de Ação/efeitos da radiação , Animais , Espaço Intracelular/efeitos da radiação , Memória/efeitos da radiação , Moluscos/fisiologia , Neurônios/citologia
6.
Electromagn Biol Med ; 27(4): 409-17, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19037790

RESUMO

The aim of present work is to explore the influence of extremely low-frequency electromagnetic fields (8.34 and 217 Hz) utilized in cell phones on habituation of the mollusk single neuron to intracellular stimuli. The isolated nervous system of the mollusk Helix Pomatia was used in the experiments. Helmholtz coils were used to expose brain ganglia to the low-frequency electromagnetic fields. Peak values of the extremely low-frequency fields were between 1 and 6 mT. Neuron electrophysiology was investigated using a standard microelectrode technique. Exposure of the neuron to the low-frequency electromagnetic fields caused dehabituation to intracellular stimulus. The effect was proportional to the magnetic induction peak value. The observed dehabituation occurs by degradation of the signal to noise ratio and by alteration of the neuron's normal function.


Assuntos
Telefone Celular , Campos Eletromagnéticos , Caracois Helix/citologia , Neurônios/efeitos da radiação , Animais , Habituação Psicofisiológica/efeitos da radiação , Espaço Intracelular/metabolismo , Espaço Intracelular/efeitos da radiação , Neurônios/fisiologia
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