Your browser doesn't support javascript.
Show: 20 | 50 | 100
Results 1 - 20 de 489
Braz. j. biol ; 82: e232525, 2022. tab, graf
Article in English | LILACS | ID: biblio-1249239


Abstract The coupling of a ligand with a molecular receptor induces a signal that travels through the receptor, reaching the internal domain and triggering a response cascade. In previous work on T-cell receptors and their coupling with foreign antigens, we observed the presence of planar molecular patterns able to generate electromagnetic fields within the proteins. These planes showed a coherent (synchronized) behavior, replicating immediately in the intracellular domain that which occurred in the extracellular domain as the ligand was coupled. In the present study, we examined this molecular transduction - the capacity of the coupling signal to penetrate deep inside the receptor molecule and induce a response. We verified the presence of synchronized behavior in diverse receptor-ligand systems. To appreciate this diversity, we present four biochemically different systems - TCR-peptide, calcium pump-ADP, haemoglobin-oxygen, and gp120-CD4 viral coupling. The confirmation of synchronized molecular transduction in each of these systems suggests that the proposed mechanism would occur in all biochemical receptor-ligand systems.

Resumo A ligação de um ligante com um receptor molecular induz um sinal que viaja através do receptor, chegando ao domínio interno e disparando uma cascata de resposta. Em trabalhos anteriores em receptores de células T e sua ligação com antígenos estranhos, observamos a presença de padrões moleculares planares capazes de gerar campos eletromagnéticos dentro das proteínas. Esses planos mostraram um comportamento coerente (sincronizado), replicando, instantaneamente, no domínio intracelular o que ocorreu no domínio extracelular, enquanto o ligante era acoplado. No presente estudo, examinamos essa transdução - a capacidade de um sinal de acoplamento de penetrar profundamente a molécula receptora e induzir uma resposta. Verificamos a presença de um comportamento coerente em sistemas diversos de receptor-ligante. Para apreciar essa diversidade, apresentamos quatro sistemas bioquímicos diferentes: TCR-peptídeo, ADP-bomba de cálcio, hemoglobina-oxigênio e gp120-CD4 acoplamento viral. A confirmação de transdução molecular sincronizada em cada um desses sistemas sugere que o mecanismo proposto ocorreria em todos os sistemas bioquímicos receptor-ligante.

Signal Transduction , Electromagnetic Fields , Receptors, Antigen, T-Cell/genetics , Ligands
Rev. cuba. invest. bioméd ; 40(2): e570, 2021. graf
Article in Spanish | LILACS, CUMED | ID: biblio-1347461


Introducción: El panorama demográfico en el mundo está cambiando. La población mayor de 60 años es el segmento que está creciendo más rápidamente y en el que las enfermedades del tejido óseo se presentan con más frecuencia, lo que aumenta la demanda de materiales y tecnologías apropiadas para restaurar estos tejidos. Objetivo: Analizar la información que se ha generado sobre el desarrollo de biomateriales compuestos para la reparación ósea, con énfasis en la identificación de las tecnologías emergentes basadas en el uso del campo electromagnético, sus aplicaciones y potencialidades. Métodos: Se consultaron trabajos científicos publicados en libros, revistas, patentes y tesis. El 80 por ciento de la documentación seleccionada pertenece al periodo 2010-2019. Análisis e integración de la información: Los métodos identificados fueron clasificados en cinco grupos: electrodeposición química, ya sea por electrólisis, electroforesis o síntesis electroforética in situ; electroporación; electrohilado; control magnético distal y bioestimulación electromagnética de células y tejidos, directamente o por la introducción de dispositivos que convierten la energía electromagnética en energía mecánica. Conclusiones: Estos métodos permiten la conformación de matrices celulares y acelulares compuestas y, además, dispositivos bioestimuladores con control de los parámetros de construcción y acción, de tal manera, que se logran procesos con mayor grado de reproducibilidad y a la medida de los requerimientos específicos para cada paciente(AU)

Introduction: The global demographic panorama is changing. The population aged over 60 years is the fastest growing segment, as well as the one where bone tissue diseases are most common, increasing the demand of appropriate materials and technologies to restore those tissues. Objective: To analyze the information so far generated about the development of composite biomaterials for bone repair, with an emphasis on the identification of emerging technologies based on the use of the electromagnetic field, its applications and potential. Methods: An analysis was performed of scientific papers published in books, journals, patents and theses. Of the documentation selected, 80 percent was from the period 2010-2019. Data analysis and integration: The methods identified were classified into five groups: chemical electrodeposition, be it by in situ electrophoretic synthesis, electrolysis or electrophoresis; electroporation; electrospinning; distal magnetic control and electromagnetic biostimulation of cells and tissues, either directly or incorporating devices which convert electromagnetic energy into mechanical energy. Conclusions: These methods permit the conformation of composite cellular and acellular matrices as well as biostimulator devices controlling construction and action parameters in such a way that the processes obtained display greater reproducibility and are more in keeping with the specific requirements of each patient(AU)

Humans , Biocompatible Materials/analysis , Electric Stimulation/methods , Electromagnetic Fields
Article in English | WPRIM | ID: wpr-828975


Objective@#This study aimed to investigate the effect of exposure to a 900 MHz electromagnetic field (EMF) on the cervical spinal cord (CSC) of rats and the possible protective effect of luteolin (LUT) against CSC tissue damage.@*Methods@#Quantitative data were obtained stereological, biochemical, immunohistochemical, and histopathological techniques. We investigated morphometric value, superoxide dismutase (SOD) level, and the expression of high-mobility group box 1 protein molecules, as well as histological changes.@*Results@#The total number of motor neurons in the EMF group significantly decreased in comparison with that in the control group ( < 0.05). In the EMF + LUT group, we found a significant increase in the total number of motor neurons compared with that in the EMF group ( < 0.05). SOD enzyme activity in the EMF group significantly increased in comparison with that in the control group ( < 0.05). By contrast, the EMF+LUT group exhibited a decrease in SOD level compared with the EMF group ( < 0.05).@*Conclusion@#Our results suggested that exposure to EMF could be deleterious to CSC tissues. Furthermore, the protective efficacy of LUT against SC damage might have resulted from the alleviation of oxidative stress caused by EMF.

Animals , Antioxidants , Pharmacology , Electromagnetic Fields , Luteolin , Pharmacology , Male , Rats , Rats, Wistar , Spinal Cord , Radiation Effects
Article in Chinese | WPRIM | ID: wpr-828200


Concerning on the safety risks caused by electromagnetic interference of patients implanted with high-risk active implantable medical devices in the environment of domestic MUs, this study evaluates and focuses on the requirements of electromagnetic compatibility in domestic and international standards for rail transit vehicles, the main mechanism of risks caused by EMI, the actual measurement of environmental data in MUs and the working performance of various active implantables in the compartment. The test results shows that all kinds of active implantable medical device samples works normally in the CRH2A EMU in China, and there is still a large margin between the measured radiation emission in MU and the limit required by the standards.

China , Electromagnetic Fields , Electromagnetic Radiation , Humans , Pacemaker, Artificial , Prostheses and Implants
Article in Chinese | WPRIM | ID: wpr-828169


Wireless power transfer (WPT) is a new power transmission way, which can be widely used in electric vehicles and other fields. Its electromagnetic environment must be analyzed to ensure safe application. A low-power wireless power transfer system experimental platform was built, with 25 W receiving power and 47 kHz resonant frequency, which was used to carry out animal experiments. Treatment mice were exposed to environment of wireless power transfer system for 5 h a day and 6 days as one cycle. At the end of every cycle, learning memory behavior of mice were detected in T-shaped maze. The exposure experiment lasted for 12 weeks. Finally, immune parameters, sex hormones and part of organ physiological structure were detected. The results are as follows: as exposure time increased, memory behavior of mice did not change obviously with no statistical difference in sex hormone either ( > 0.05), the concentration of immune factors including tumor necrosis factor-α (TNF-α), interleukin 6 (IL-6) and interleukin-1 beta (IL-1β) significantly increased ( < 0.05), and the structure of some organs showed some changes. The experimental results show that the environment of the wireless power transfer system has no effect on the memory behavior of mice, and has some effect on physiological properties of mice.

Animals , Cytokines , Electric Power Supplies , Electricity , Electromagnetic Fields , Gonadal Steroid Hormones , Memory , Mice , Wireless Technology
São José dos Campos; s.n; 2020. 70 p. il., graf., tab..
Thesis in Portuguese | LILACS, BBO | ID: biblio-1150925


A utilização de estimulação biofísica através da modalidade de campo eletromagnético pulsado (CEMP) para o tratamento de diversas condições no tecido ósseo tem despertado o interesse científico há décadas. Entretanto, a grande variedade nos parâmetros e protocolos utilizados e a divergência de resultados na literatura dificultam o estabelecimento de uma metodologia que seja eficaz no contexto da terapia com implantes osseointegrados. Dessa forma, torna-se importante avaliar o efeito de diferentes tempos de aplicação do CEMP padronizado em diferentes momentos no processo de osseointegração de implantes de titânio inseridos em tíbias de ratos. Para isso, foram utilizados 60 animais (Rattus norvegicus, variação albinus, Wistar), randomizados em três grupos experimentais: controle, teste A (GTA) submetidos por 3 horas de CEMP, e teste B (GTB) com 1 hora de CEMP, sendo que, a exposição ocorreu em 5 dias semanalmente durante o período experimental. Todos os animais receberam implantes em ambas as tíbias, e a aplicação do CEMP ocorreu apenas nos grupos teste com parâmetros fixos de ± 1 mT, 15 Hz, com 25 ciclos repetidos por 200 microssegundos. Após a eutanásia as peças foram separadas e preparadas para o teste mecânico, análises histomorfométricas, microtomografia computadorizada (µCT) e ensaios biológicos in vitro. Os dados foram tabulados e a análise de variância ANOVA foi aplicada, com nível de significância de 5%. Os resultados obtidos revelaram que, GTB apresentou melhores resultados em comparação ao GTA nos testes de torque de remoção em 07 dias; no volume ósseo e densidade mineral óssea, ambos em 07, 21 e 45 dias; na proliferação celular em 21 dias, na viabilidade celular em 07 e 45 dias, no conteúdo de proteína total em 07 dias e nódulos de mineralização em 03 e 07 dias. O GTA apresentou melhor desempenho na avaliação da espessura do osso trabecular em 03 dias e na proliferação celular em 03 e 45 dias comparado ao GTB. Os grupos teste apresentaram resultados superiores ao controle nas avaliações de contato osso-implante, espessura do osso trabecular, na viabilidade celular, conteúdo de proteína total e fosfatase alcalina. Na análise histomorfométrica e no número de trabéculas não houve diferenças entre os grupos teste. Com os resultados pode-se concluir que, a aplicação do campo eletromagnético pulsado como um bioestimulador foi efetivo na otimização dos eventos no tecido ósseo que acarretam na osseointegração, especialmente quando aplicado por menor tempo e nos períodos iniciais do reparo ósseo(AU)

The use of biophysical stimulation through the pulsed electromagnetic field modality (PEMF) for the treatment of various conditions in bone tissue has aroused scientific interest for decades. However, the wide variety of parameters and protocols used and the divergence of results in the literature make it difficult to establish a methodology that is effective in the context of therapy with osseointegrated implants. Thus, it is important to evaluate the effect of different application times of the standardized PEMF at different times in the osseointegration process of titanium implants inserted in tibiae of rats. For this, 60 animals (Rattus norvegicus, variation albinus, Wistar) were used, randomized in three experimental groups: control, test A (GTA) submitted for 3 hours of CEMP, and test B (GTB) with 1 hour of PEMF, and the exposure occurred in 5 days weekly during the trial period. All animals received implants in both tibiae, and the application of PEMF only occurred in the test groups with fixed parameters ± 1 mT, 15 Hz, with 25 cycles repeated for 200 microseconds. After euthanasia, the pieces were separated and prepared for mechanical testing, histomorphometric analysis, computed microtomography (µCT) and in vitro biological tests. Data were tabulated and ANOVA analysis of variance was applied, with a significance level of 5%. The results obtained revealed that, GTB presented better results in comparison to GTA in the removal torque tests in 07 days; in bone volume and bone mineral density, both at 07, 21 and 45 days; cell proliferation in 21 days, cell viability in 07 and 45 days, total protein content in 07 days and mineralization nodules in 03 and 07 days. GTA performed better in assessing trabecular bone thickness in 03 days and in cell proliferation in 03 and 45 days compared to GTB. The test groups showed results superior to the control in assessments of boneimplant contact, trabecular bone thickness , in cell viability, total protein content and alkaline phosphatase. In the histomorphometric analysis and in the number of trabeculae, there were no differences between the test groups. With the results it can be concluded that the application of the pulsed electromagnetic field as a biostimulator was effective in the optimization of the events in the bone tissue that result in osseointegration, especially when applied for a shorter time and in the initial periods of bone repair(AU)

Osseointegration , Electromagnetic Fields , Bone-Anchored Prosthesis/adverse effects
Int. j. morphol ; 37(2): 719-723, June 2019. tab, graf
Article in English | LILACS | ID: biblio-1002283


Mobile phone use has increased rapidly. The central nervous system has been shown to be adversely affected by its electromagnetic field (EMF) resulting in headache and sleep disturbances. How the cells make up the CNS and are affected by EMF is unclear. However, because of their central role in inflammation through diverse stimuli including radiation, this study aimed to investigate the effects of electromagnetic fields induced by mobile phones on mast cells in rat dura mater. A total of 18 adult, female, SpragueDawley rats were divided into two groups. The choice of female rats for his study was based on recent surveys demonstrating that mobile phone use is more frequent and prolonged among females. The study group was exposed to 900 MHz electromagnetic field (1 h/day for 45 days). In the end of the study, duramater tissue was extracted and stained using Toluidine blue. Mast cells were counted and results were analysed using Student t test. Mean mast cell number was 202.33±9.82 and 456.78±35.01 in the control and study groups, respectively (p<0.05). Analysis of serum electrolyte and immunoglobulin E levels showed no statistically significant difference between the two groups (p>0.05). The study showed that mobile phone exposure increased mast cell number and degranulation in rat dura mater. Further studies are required to evaluate the clinical implications of these findings.

El uso del teléfono móvil ha aumentado rápidamente. Se ha demostrado que el sistema nervioso central (SNC) se ve afectado de manera adversa debido al campo electromagnético (CEM) que produce dolor de cabeza y trastornos del sueño. No está claro cómo se ve afectada la composición celular del SNC por el CEM. Sin embargo, debido a su función principal en la inflamación a través de diversos estímulos que incluyen la radiación, este estudio tuvo como objetivo investigar los efectos de los campos electromagnéticos inducidos por los teléfonos móviles en los mastocitos de la duramadre de ratas. Un total de 18 ratas Sprague-Dawley adultas, hembras, se dividieron en dos grupos. Se usaron ratas hembras para este estudio en base a investigaciones recientes que han demostrado que el uso de teléfonos móviles es más frecuente y prolongado en las mujeres. Los grupos de estudio fueron expuestos a un campo electromagnético de 900 MHz (1 h / día durante 45 días). Al término del estudio, fue extirpado el tejido de la duramadre y teñido con azul de toluidina. Se contaron los mastocitos y se analizaron los resultados utilizando la prueba t de Student. La cantidad media de células cebadas fue de 202,33 ± 9.82 y 456,78 ± 35,01 en los grupos control y estudio, respectivamente (p <0,05). El análisis del electrolito sérico y los niveles de inmunoglobulina E no mostraron diferencias estadísticamente significativas entre los dos grupos (p> 0,05). El estudio mostró que la exposición a teléfonos móviles aumentó el número de mastocitos y la desgranulación en la duramadre de las ratas. Se requieren estudios adicionales para evaluar las implicaciones clínicas de estos hallazgos.

Animals , Rats , Cell Phone , Dura Mater/radiation effects , Electromagnetic Fields/adverse effects , Mast Cells/radiation effects , Rats, Sprague-Dawley
Braz. j. otorhinolaryngol. (Impr.) ; 85(3): 282-289, May-June 2019. tab, graf
Article in English | LILACS | ID: biblio-1011624


Abstract Introduction: In daily life biological systems are usually exposed to magnetic field forces at different intensities and frequencies, either directly or indirectly. Despite negative results, the therapeutic use of the low dose magnetic field has been found in recent studies. The effect of magnetic field forces on cochlear cells is not clear in the literature. Objective: In our study, we first applied in vivo pulsed magnetic fields to laboratory rats to investigate the effects on cochlea with distortion product otoacoustic emission test followed by histopathological examinations. Methods: Twelve rats were included in this study, separated into two groups as study group and control group. The rats in the study group were exposed to 40 Hz pulsed magnetic field for 1 h/day for 30 days; the hearing of the rats was controlled by otoacoustic emission test. Also, their cochleas were removed and histochemical examination was performed by Caspase-3, Caspase-9, and TUNEL methods. Results: A statistically significant difference was determined (p < 0.05) when the hearing thresholds of the groups obtained by using 5714 Hz and 8000 Hz stimuli were compared by Kruskal-Wallis test. A significant reaction was observed in the study group, especially in the outer ciliated cells during immunohistochemical examinations by using Caspase-3 and Caspase-9 methods. A significantly positive difference was determined in the study group, especially at the outer ciliated cells and the support cells of the corti organ, when compared to the control group (p < 0.05) by the TUNEL method. Conclusion: According to the results of our study, the very low dose magnetic field, which is considered to be used for therapeutic purposes recently, can cause both auditory function defects and histopathologic damage in cochlear cells.

Resumo Introdução: Os sistemas biológicos são geralmente expostos a forças de campo magnético em diferentes intensidades e frequências, direta ou indiretamente, na vida diária. Apesar dos resultados negativos, o uso terapêutico do campo magnético de baixa dose tem sido encontrado em estudos recentes. O efeito das forças do campo magnético sobre as células cocleares não está claro na literatura. Objetivo: Em nosso estudo, aplicamos pela primeira vez campos magnéticos pulsados in vivo em ratos de laboratório para investigar os efeitos na cóclea através do teste de emissão otoacústica por produto de distorção e análises histopatológicas. Método: Doze ratos foram incluídos neste estudo, os quais foram separados em dois grupos, grupo de estudo e grupo controle. Os ratos do grupo de estudo foram expostos a campo magnético pulsado de 40 Hz por 1 hora/dia por 30 dias, e a audição dos ratos foi controlada por testes de emissão otoacústica. Além disso, suas cócleas foram colhidas e o exame histoquímico foi feito pelos métodos caspase-3, caspase-9 e TUNEL. Resultados: Foi determinada uma diferença estatisticamente significante (p < 0,05) quando os limiares auditivos dos grupos obtidos por meio dos estímulos de 5714 Hz e 8000 Hz foram comparados pelo teste de Kruskal-Wallis. Uma reação significante foi observada no grupo de estudo, especialmente nas células ciliadas externas nas análises imuno-histoquímicas, com os métodos caspase-3 e caspase-9. Uma diferença significantemente positiva foi determinada no grupo de estudo, especialmente nas células ciliadas externas e nas células de suporte do órgão de Corti, quando comparadas com o grupo controle (p < 0,05) pelo método TUNEL. Conclusão: De acordo com os resultados do nosso estudo, o campo magnético de dose baixa, que tem sido considerado para uso terapêutico recentemente, pode causar defeitos na função auditiva e danos histopatológicos nas células cocleares.

Animals , Male , Rats , Cochlea/pathology , Hair Cells, Auditory, Outer/pathology , Electromagnetic Fields/adverse effects , Immunohistochemistry , Rats, Wistar , Otoacoustic Emissions, Spontaneous , Statistics, Nonparametric
Article in Chinese | WPRIM | ID: wpr-775240


OBJECTIVE@#To investigate the effect of low-frequency pulsed electromagnetic fields (PEMF) on the maturation and mineralization of rat cranial osteoblasts and its relation to IGF-1R/NO signaling pathway.@*METHODS@#The rat osteoblasts were isolated and cultured and randomly divided into blank control group, PEMF group, GSK group (IGF-1R blocker) and PEMF+GSK group. The cells were treated with 50 Hz 0.6 mT PEMF for 1.5 h/d. After 3 d of PEMF treatment, the expressions of protein kinase (AKT), inducible nitric oxide synthase (iNOS) and cGMP-dependent protein kinase (PKG) were detected by Western blotting; on 6 d of PEMF treatment alkaline phosphatase (ALP) activity was determined; on 12 d of PEMF treatment the calcification nodule formation was demonstrated by Alizarin red staining.@*RESULTS@#NO level was significantly increased in rat osteoblasts treated with 50 Hz 0.6 mT PEMF for 1.5 h/d. Western blot analysis showed that the expressions of AKT, iNOS and PKG protein in PEMF group were higher than those in the control group (all <0.01); the ALP activity was increased(<0.05), and the PEMF group had the largest area of Alizarin red staining (<0.01). The expressions of AKT, iNOS and PKG protein in GSK group were lower than those in the control group; the ALP activity was decreased (<0.05), and the GSK group had the least area of Alizarin red staining (<0.01). The expressions of AKT, iNOS, PKG protein, the ALP activity and the area of Alizarin red staining in PEMF+GSK group were between PEMF group and GSK group.@*CONCLUSIONS@#PEMF may enhance the maturation and mineralization of rat cranial osteoblasts through IGF-1R/NO signaling pathway.

Animals , Cell Differentiation , Cell Proliferation , Cells, Cultured , Electromagnetic Fields , Nitric Oxide , Metabolism , Osteoblasts , Radiation Effects , Rats , Receptor, IGF Type 1 , Metabolism , Signal Transduction , Radiation Effects
Article in Chinese | WPRIM | ID: wpr-774004


Objective To compare the effects of 50-Hz 0.6-mT low-frequency pulsed electromagnetic fields(PEMFs) and 50-Hz 1.8-mT sinusoidal alternating electromagnetic fields(SEMFs) in preventing bone loss in tail-suspended rats,with an attempt to improve the prevention and treatment of bone loss caused by weightlessness.Methods Tail-suspension rat models were used to simulate microgravity on the ground. Forty rats were randomly divided into four groups[control group,hindlimb-suspended(HLS) group,HLS+PEMFs group,and HLS+SEMFs group],with 10 rats in each group. In the PEMFs treatment group and SEMFs treatment group,the intervention was 90 min per day. Rats were sacrificed after four weeks. Bone mineral density(BMD) of femur and vertebra was measured by dual-energy X-ray absorptiometry and biomechanical strength by AG-IS biomechanical instrument. Serum osteocalcin(OC),tartrate-resistant acid phosphatase 5b(Tracp 5b),parathyroid hormone(PTH),and cyclic adenosine monophosphate(cAMP) were detected by ELISA. The microstructure of bone tissue was observed by Micro-CT and HE staining.Results The BMD of the femur(P=0.000) and vertebrae(P=0.001) in the HLS group was significantly lower than in the control group;the BMD of the femurs(P=0.001) and vertebrae(P=0.039) in the HLS+PEMFs group was significantly higher than in the HLS group;the BMD of the femurs in the HLS+SEMFs group was significantly higher than in the HLS group(P=0.003),but the BMD of the vertebrae showed no significant difference(P=0.130). There was no significant difference in the BMD of the femur(P=0.818) and vertebrae(P=0.614) between the HLS+PEMFs group and the HLS+SEMFs group. The maximum load(P=0.000,P=0.009) and elastic modulus(P=0.015,P=0.009) of the femurs and vertebrae in the HLS group were significantly lower than those in the control group;the maximum load of the femur(P=0.038) and vertebrae(P=0.087) in the HLS+PEMFs group was significantly higher than that in the HLS group,but the elastic modulus was not significantly different from that in the HLS group(P=0.324,P=0.091). The maximum load(P=0.190,P=0.222) and elastic modulus(P=0.512,P=0.437) of femurs and vertebrae in the HLS+SEMFs group were not significantly different from those in the HLS group. There were no significant differences in the maximum load and elastic modulus of femurs(P=0.585,P=0.948) and vertebrae(P=0.668,P=0.349) between the HLS+PEMFs group and the HLS+SEMFs group. The serum OC level in the HLS group was significantly lower than that in the control group(P=0.000),and the OC level in HLS+PEMFs group(P=0.000) and HLS+SEMFs group(P=0.006) were significantly higher than that in the HLS group. The serum Tracp 5b concentration in the HLS group was significantly higher than that in the control group(P=0.011). There was no significant difference between the HLS+PEMFs group(P=0.459) and the HLS+SEMFs group(P=0.469) compared with the control group.Serum Tracp 5b concentrations in the HLS+PEMFs group(P=0.056) and the HLS+SEMFs group(P=0.054) were not significantly different from those in the HLS group. The PTH(P=0.000) and cAMP concentrations(P=0.000) in the HLS group were significantly lower than those in the control group. The PTH(P=0.000,P=0.000) and cAMP concentrations(P=0.000,P=0.000) in the HLS+PEMFs group and the HLS+SEMFs group were significantly higher than in the HLS group. The femoral cancellous bone of the HLS group was very sparse and small compared with the control group. The density and volume of the cancellous bone were similar among the control group,HLS+PEMFs group,and HLS+SEMFs group. Compared with the control group,the HLS group had lower BMD(P=0.000),bone volume (BV)/tissue volume(TV)(P=0.000),number of trabecular bone (Tb.N)(P=0.000),and trabecular thickness(Tb.Th)(P=0.000) and higher trabecular bone dispersion(Tb.Sp)(P=0.000) and bone surface area(BS)/BV(P=0.000). Compared with the HLS group,the HLS+PEMFs group and the HLS+SEMFs group had significantly lower Tb.Sp(P=0.000,P=0.000) and BS/BV(P=0.000,P=0.000) and significantly increased BMD(P=0.000,P=0.000),BV/TV(P=0.001,P=0.004),Tb.Th(P=0.000,P=0.001),and Tb.N(P=0.000,P=0.001). The trabecular thickness significantly differed between the HLS+PEMFs group and the HLS+SEMFs group(P=0.024). The HLS group(P=0.000),HLS+PEMFs group(P=0.000),and HLS+SEMFs group(P=0.000) had the significantly lower osteoblast density on the trabecular bone surface than the control group;however,it was significantly higher in the HLS+SEMFs group(P=0.000) and the HLS+PEMFs group(P=0.000) than in the HLS group. The HLS group had significantly lower density of osteoblasts in the endothelium than the control group(P=0.000);however,the density of osteoblasts was significantly higher in HLS+PEMFs group(P=0.000) and HLS+SEMFs group(P=0.000) than HLS group and was significantly higher in HLS+PEMFs group than in HLS+SEMFs group(P=0.041). Compared with the control group,a large number of fatty cavities were produced in the bone marrow cavity in the HLS group,but the fat globules remarkably decreased in the treatment groups,showing no significant difference from the control group. The number of adipose cells per mm bone marrow in the HLS group was 4 times that of the control group(P=0.000);it was significantly smaller in the HLS+PEMFs group(P=0.000) and HLS+SEMFs group(P=0.000) than in the HLS group,whereas the difference between the HLS+PEMFs group and the HLS+SEMFs group was not statistically significant(P=0.086). Conclusions 50-Hz 0.6-mT PEMFs and 50-Hz 1.8-mT SEMFs can effectively increase bone mineral density and biomechanical values in tail-suspended rats,increase the concentration of bone formation markers in rat blood,activate the cAMP pathway by affecting PTH levels,and thus further increase the content of osteoblasts to prevent the deterioration of bone micro-structure. In particular,PEMFs can prevent the reduction of bone mineral density and maximum load value by about 50% and increase the bone mass of tail-suspended rats by promoting bone formation.

Absorptiometry, Photon , Animals , Bone Density , Electromagnetic Fields , Femur , Rats , Rats, Sprague-Dawley , Weightlessness
Article in Chinese | WPRIM | ID: wpr-774003


Objective To observe the effect of low-frequency pulsed electromagnetic fields(PEMFs) on bone formation in rat osteoblasts(ROBs) and explore the mechanism of action of the cyclic adenosine monophosphate(cAMP)/protein kinase A(PKA)/cyclic adenosine effect binding protein(CREB) signaling pathway.Methods The skulls of newborn Wistar rats were harvested,and the ROBs were obtained by multiple enzymatic digestion methods for subculture. After treatment with 50 Hz 0.6 mT PEMFs for 3,6,and 9 days,the alkaline phosphatase(ALP) concentration in ROBs was detected;after 0,15,30,60,90,and 120 min,the expression of bone formation-related factor(RUNX2),the protein expression of osteogenesis-associated transcription factor(OSX),the cAMP concentration,as well as the protein expressions of p-PKA,p-CREB,and CREB were detected. The p-CREB nuclear translocation was observed. After interference with IFT88 by RNA interference,the expressions of RUNX2,OSX,p-PKA,and p-CREB protein in ROBs were detected.Results After treatment with PEMFs for 3,6,and 9 days,the ALP activity values in ROBs were 24.356±4.911,37.688±2.151,and 39.922±5.486,respectively,which were significantly higher than 18.531±2.401(P=0.0121),33.675±4.366(P=0.0324),and 36.574±1.339(P=0.0134) in the control groups. RUNX2 and OSX activities in ROBs were significantly higher than untreated group after PEMFs treatment for 30(P=0.0042 and P=0.0058),60(P=0.0097 and P=0.0079),and 90 min(P=0.0083 and P=0.0098). After PEMFs treatment for 30(P=0.0012) and 60 min(P=0.0035),the cAMP concentrations in ROBs were significantly higher than that in untreated group. After PEMFs treatment for 15(P=0.0018),30(P=0.0087),90(P=0.0250),and 120 min(P=0.0350),the p-PKA levels in ROBs were significantly higher than that in the untreated group. After PEMFs treatment for 15(P=0.0075),30(P=0.0017),60(P=0.0074),and 90 min(P=0.0096),the level of p-CREB in the ROBs was significantly higher than in the untreated group. After PEMFs treatment of ROBs for 15 min,CREB phosphorylated and accumulated in the nuclei. PKA and p-PKA were co-localized with primary cilia and stained,and it was found that p-PKA was localized on the primary cilia. After the primary cilia was removed by RNA interference,the protein expression levels of p-PKA(F=78.602,P=0.0270),p-CREB(F=76.082,P=0.0089),RUNX2(F=41.064,P=0.0230) and OSX(F=57.524,P=0.0310) were significantly lower than those of the non-interfered group.Conclusion PEMFs promote bone formation in ROBs by activating the primary cilia-associated cAMP/PKA/CREB signaling pathway.

Animals , Cyclic AMP-Dependent Protein Kinases , Electromagnetic Fields , Osteoblasts , Osteogenesis , Rats , Rats, Wistar
Article in English | WPRIM | ID: wpr-763018


Technological advances of mankind, through the development of electrical and communication technologies, have resulted in the exposure to artificial electromagnetic fields (EMF). Technological growth is expected to continue; as such, the amount of EMF exposure will continue to increase steadily. In particular, the use-time of smart phones, that have become a necessity for modern people, is steadily increasing. Social concerns and interest in the impact on the cranial nervous system are increased when considering the area where the mobile phone is used. However, before discussing possible effects of radiofrequency-electromagnetic field (RF-EMF) on the human body, several factors must be investigated about the influence of EMFs at the level of research using in vitro or animal models. Scientific studies on the mechanism of biological effects are also required. It has been found that RF-EMF can induce changes in central nervous system nerve cells, including neuronal cell apoptosis, changes in the function of the nerve myelin and ion channels; furthermore, RF-EMF act as a stress source in living creatures. The possible biological effects of RF-EMF exposure have not yet been proven, and there are insufficient data on biological hazards to provide a clear answer to possible health risks. Therefore, it is necessary to study the biological response to RF-EMF in consideration of the comprehensive exposure with regard to the use of various devices by individuals. In this review, we summarize the possible biological effects of RF-EMF exposure.

Apoptosis , Brain , Cell Phone , Central Nervous System , Electromagnetic Fields , Human Body , In Vitro Techniques , Ion Channels , Magnets , Models, Animal , Myelin Sheath , Nervous System , Neurons , Smartphone
Article in Chinese | WPRIM | ID: wpr-772556


In the electromagnetic compatibility standards of active implantable medical devices such as ISO 14117,radiated immunity test above 450 MHz frequency is recommended to be carried out in the electromagnetic shielding room.However,different test locations and the shape/size of the shielding room may lead to very different electromagnetic field distribution in the radiation exposure area of the sample,thus affecting the consistency of the test.With the model built by COMSOL software,this paper analyzes the impact of different parameters,such as size of the room and position of torso simulator on the distribution of field intensity,and reaches results about the distribution of field intensity on the torso simulator area under tow sizes of shielding rooms and two typical test positions.The results show that the experimental consistency of the electric field intensity on the surface directly below the center of the antenna is not good enough,which may affect the repeatability of the test.

Electromagnetic Fields , Prostheses and Implants
Article in Chinese | WPRIM | ID: wpr-772337


BACKGROUND@#Electromagnetic navigation bronchoscopy (ENB) has become the latest minimally invasive diagnostic and therapeutic technique due to its characteristics, e.g., non-invasion, accuracy, real-time positioning. In this study, we investigated the application of ENB biopsy combined with Massage staining in the diagnosis and treatment of peripheral pulmonary lesions (PPL).@*METHODS@#The clinical data of 15 PPL patients undergoing ENB biopsy plus Massage staining between August 2017 and January 2018 were retrospectively reviewed. Among them, there were 12 male and 3 female, and the mean age was (51.3±2.1) years old.@*RESULTS@#The diameter of PPLs ranged from 6 mm to 36 mm (mean: 14.0 mm). The successful biopsy rate was 66.7%. All patients successfully underwent Massage staining. The distance between the centers of staining and lesion was (1.0±0.4) cm, and the diameter of staining was (2.8±0.6) cm. The mean operation time was (26.7±5.3 ) min, and the mean blood loss during surgery was (3.3±1.5) mL. There was no pneumothorax, hemothorax and pulmonary vascular injury during the procedure.@*CONCLUSIONS@#The ENB biopsy plus Massage staining technique caused very few complications, and provided high precision, which warrants further application.

Bronchoscopy , Methods , Electromagnetic Fields , Female , Humans , Lung Diseases , Diagnosis , General Surgery , Lung Neoplasms , Diagnosis , General Surgery , Male , Middle Aged , Reproducibility of Results , Retrospective Studies , Sensitivity and Specificity , Staining and Labeling , Methods
Article in Chinese | WPRIM | ID: wpr-772118


OBJECTIVE@#To investigate the effects of millimeter wave (MMW) exposure on apoptosis of human melanoma A375 cells and explore the mechanisms.@*METHODS@#Through electromagnetic field calculation we simulated MMW exposure in cells and calculated the specific absorption rate (SAR). The optimal irradiation parameters were determined according to the uniformity and intensity of the SAR. A375 cells were then exposed to MMV for 15, 30, 60, or 90 min, with or without pretreatment with the caspase-3 inhibitor AC-DEVD-fmk (10 μmol/L) for 1 h at 90 min before the exposure. CCK-8 assay was used to assess the changes in the viability and Annexin-V/ PI staining was used to detect the apoptosis of the cells following the exposures; Western blotting was used to detect the expression of caspase-3 in the cells.@*RESULTS@#The results of electromagnetic field calculation showed that for optimal MMV exposure, the incident field needed to be perpendicular to the bottom of the plastic Petri dish with the antenna placed below the dish. CCk-8 assay showed that MMW exposure significantly inhibited the cell viability in a time-dependent manner ( < 0.05); exposures for 15, 30, 60, and 90 min all resulted in significantly increased apoptosis of the cells ( < 0.05). The cells with MMW exposure showed significantly increased expression of caspase-3. The inhibitory effect of MMW on the cell viability was antagonized significantly by pretreatment of the cells with AC-DEVD-fmk ( < 0.05), which increased the cell viability rate from (36.7±0.09)% to (59.8±0.06)% ( < 0.05).@*CONCLUSIONS@#35.2 GHz millimeter wave irradiation induces apoptosis in A375 cells by activating the caspase-3 protein.

Apoptosis , Caspase 3 , Metabolism , Caspase Inhibitors , Pharmacology , Cell Line, Tumor , Cell Survival , Electromagnetic Fields , Enzyme Activation , Humans , Magnetic Field Therapy , Melanoma , Pathology , Therapeutics , Time Factors
São José dos Campos; s.n; 2019. 55 p. il., tab., graf..
Thesis in Portuguese | LILACS, BBO | ID: biblio-1016892


A doença periodontal (DP) resulta de uma infecção polimicrobiana complexa, levando à destruição dos tecidos periodontais, como consequência da perturbação da homeostase entre a microbiota subgengival e os mecanismos de defesas do hospedeiro em indivíduos suscetíveis. A deficiência estrogênica (DE) é a causa mais comum de osteoporose. A osteoporose é definida como uma doença crônica, multifatorial, provenientes de uma desordem esquelética que promove fragilidade óssea pela redução de sua massa. Vários estudos experimentais têm demonstrado que a estimulação com Campo Eletromagnético Pulsátil (CEMP) pode promover a osteogênese e potencialmente aumentar a mineralização óssea e também, reduzir a inflamação aguda e crônica em tecidos moles e duros. Frente a isso, este estudo teve como objetivo, avaliar por meio da histomorfometria, imunoistoquímica e microtomografia computadorizada (MicroCT), a influência do CEMP na DP induzida em ratas ovariectomizadas e Sham. Para a pesquisa, foram utilizadas 60 ratas adultas (Rattus norvegicus, variação albinus, Wistar) com 3 meses de idade, pesando em torno de 300 gramas e em todos os animais a DP foi induzida. As ratas foram randomizadas em dois grupos experimentais, contendo 30 animais cada, classificados em ovariectomia simulada (Sham) e Ovariectomizada (Ovz), respectivamente. Os grupos foram divididos em dois subgrupos com 15 animais cada: Sham-S (n=15): não receberam terapia com CEMP e este foi nosso grupo controle. Sham-CEMP (n=15): receberam terapia com CEMP. Ovz­O (n=15): não receberam terapia com CEMP. Ovz­CEMP (n=15): receberam terapia com CEMP. As análises histomorfométrica, e MicroCT foram realizadas e os dados obtidos foram submetidos à análise de variância (ANOVA) e teste de Tukey, ambos com nível de significância convencional de 95% e não apresentaram nenhuma diferença estatisticamente significante. Na análise semiquantitativa para os biomarcadores RANKL e OPG, o subgrupo Ovz-O apresentou maior expressão do biomarcador RANKL e menor expressão do biomarcador OPG em relação aos outros subgrupos. Na análise quantitativa da expressão do biomarcador TRAP não foi encontrado nenhuma diferença estatisticamente significante. Apesar de não encontramos evidências significativas da terapia com CEMP na DP em ratas ovariectomizadas, o presente estudo nos sugere que o CEMP pode apresentar um efeito benéfico na remodelação óssea(AU)

Periodontal disease (PD) results from a complex polymicrobial infection, leading to the destruction of periodontal tissues as a consequence of the disturbance of homeostasis between the subgingival microbiota and the host defense mechanisms in susceptible individuals. Estrogen deficiency is the most common cause of osteoporosis. Osteoporosis is defined as a chronic, multifactorial disease from a skeletal disorder that promotes bone fragility by reducing its mass. Several experimental studies have shown that Pulsed Electromagnetic Field (PEMF) stimulation can promote osteogenesis and potentially increase bone mineralization and also reduce acute and chronic inflammation in soft and hard tissues. The aim of this study was to evaluate, through histomorphometry, immunohistochemistry and computerized microtomography (MicroCT), the influence of PEMF on PD induced in ovariectomized and Sham rats. For the research, 60 adult rats (Rattus norvegicus, albinus variant, Wistar) at 3 months of age, weighing around 300 grams were used and in all animals PD was induced. The rats were randomized into two experimental groups, containing 30 animals each, classified as simulated ovariectomy (Sham) and Ovariectomized (Ovz), respectively. The groups were divided into two subgroups with 15 animals each: Sham-S (n = 15): did not receive PEMF therapy and this was our control group. Sham-PEMF (n = 15): received PEMF therapy. Ovz-O (n = 15): did not receive PEMF therapy. Ovz-PEMF (n = 15): received PEMF therapy. The histomorphometric and MicroCT analyzes were performed and the data were submitted to analysis of variance (ANOVA) and Tukey's test, both with a 95% significance level and did not present any statistically significant difference. In the semiquantitative analysis for RANKL and OPG biomarkers, the Ovz-O subgroup showed higher expression of the RANKL biomarker and lower expression of the OPG biomarker in relation to the other subgroups. In the quantitative analysis of TRAP biomarker expression no statistically significant difference was found. Although we did not find significant evidence of PEMF therapy in PD in ovariectomized rats, the present study suggests that PEMF may have a beneficial effect on bone remodeling(AU)

Humans , Periodontal Diseases/complications , Osteoporosis/drug therapy , Bone Remodeling/physiology , Electromagnetic Fields/adverse effects
Rev. chil. dermatol ; 35(3): 95-101, 2019. ilus
Article in Spanish | LILACS | ID: biblio-1116407


Debido al acelerado envejecimiento de la población, cada vez es mayor la cantidad de usuarios portado-res de dispositivos electrónicos cardíacos implan-tables (DECI). Muchos de estos pacientes se verán enfrentados a procedimientos dermatológicos que con frecuencia utilizan equipos de electrocirugía. Es-tos tienen riesgo potencial de producir interferencias electromagnéticas (IEM), y por lo tanto alterar el fun-cionamiento de estos dispositivos. Si bien no todos los DECI tienen las mismas características, las nuevas tec-nologías de estos dispositivos han disminuido, aunque no eliminado completamente, el riesgo de IEM. Este artículo tiene como propósito revisar el tema y recopilar las recomendaciones generales que todo dermatólogo debe conocer tanto en la fase preoperatoria, intraoperatoria, como postoperatoria al utilizar equipos de electrocirugía en un paciente con DECI.

Due to the accelerated population aging, an increa-sing number of users is carrying cardiac implantable electronic devices (CIEDs). Many of these patients will face dermatological procedures that often use electrosurgical equipment. The latter has the poten-tial to produce electromagnetic interference (EMI), and therefore alter the operation of these devices. While not all CIEDs have the same characteristics, new technologies for these devices have decreased if not eliminated completely the risk of EMI.The purpose of this article is to review CIED topic and compile general recommendations that every dermatologist should be aware of, both in the preoperative, intraoperative, and postoperative phases when using electrosurgery equipment in a patient with CIED.

Humans , Pacemaker, Artificial , Defibrillators, Implantable , Electromagnetic Fields/adverse effects , Electrosurgery/methods , Dermatologic Surgical Procedures , Postoperative Care , Preoperative Care , Heart-Assist Devices , Intraoperative Complications/prevention & control
Article in English | WPRIM | ID: wpr-717582


BACKGROUND: Hypnosis monitors analyze small-amplitude electrical signals transmitted from the brain that could be exposed to the electromagnetic field that occurs around the body during electrocautery (ECT). We investigated the influence of ECT on hypnosis monitoring during anesthesia. METHODS: We simultaneously monitored BIS and uCON during 50 gynecologic oncology surgeries. During the episodes of ECT, we compared the absolute difference (a-Diff) between the baseline index and the most deviated index after ECT over either 30–60 s (ECT30–60) or more than 60 s (ECT > 60) between the monitors. We also investigated the bias and the limits of agreement between the monitors. RESULTS: Between the two monitors, the a-Diff of ECT30–60 was 1.4 ± 1.1 for the BIS, which was significantly greater than 0.6 ± 0.9 for the uCON (P = 0.003), and the a-Diff of ECT > 60 was 16.5 ± 8.2 for the BIS, which was also significantly greater than 1.4 ± 1.3 for uCON (P 60 was significantly greater than that during ECT30–60 (P 60 (P = 0.056). The estimated bias between the monitors was 6.3 ± 9.8 and 95% limits agreement was –12.3 to 25.0. CONCLUSIONS: Prolonged ECT intervention might lead to spurious estimations of quantitative EEG indexes. Therefore, hypnosis should be clinically assessed in combination with scrutinized judgment of relevant clinical symptoms and signs for hypnosis.

Anesthesia , Anesthesia, General , Bias , Brain , Electrocoagulation , Electroencephalography , Electromagnetic Fields , Hypnosis , Judgment , Magnets