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Objective:To analyze the changes in the transcriptome of mouse fibroblasts after exposure to extremely low frequency electromagnetic fields (ELF-EMFs) using next-generation sequencing technology, and to screen out related pathways and genes that might be involved in the regulation of fibroblast growth by ELF-EMFs.Methods:The mouse NIH/3T3 cells were divided into the radiation group and the normal control group.The cells in the radiation group were placed in a 0.2 mT, 50 Hz electromagnetic radiation system, and the cells in the normal control group was placed in the same coil system under the same conditions without power.After 24-hour culture in a cell incubator, RNA was extracted.The next-generation high-throughput sequencing technology was used to sequence the transcriptomes of the two groups, and perform gene function annotation and signal pathway database analysis on the selected differential genes.Some highly expressed genes were screened out and verified by real-time fluorescent quantitative PCR.Results:A total of 17 980 genes were identified in the transcriptome sequencing, and there were 140 significantly differentially expressed genes (DEGs), of which 120 were up-regulated and 20 were down-regulated.DEGs were enriched in enzyme catalytic activity, cell metabolism process, biological regulation, biosynthesis and so on.According to the Kyoto Encyclopedia of Genes and Genomes analysis, the DEGs mainly involved 55 pathways, among which the most enriched 10 pathways were aminoacyl-tRNA biosynthesis, platelet activation, neurotrophin signaling pathway, renin-angiotensin system, etc., closely related to cell biosynthesis.The DEGs that might be involved in the post-irradiation stress of cells were further screened out, including mitogen activated protein kinase 12 ( MAPK12), neurotrophic tyrosine kinase receptor type 3 ( NTRK3), angiotensin Ⅱ receptor type 2 ( AGTR2), vascular endothelial growth factor ( VEGF), etc.Real-time fluorescent quantitative PCR results showed that the relative expression levels of MAPK12, NTRK3, AGTR2, VEGF mRNA in the radiation group were 2.389±0.003, 2.481±0.350, 2.354±0.081, 1.559±0.110, respectively, which were significantly higher than 1.011±0.190, 1.011±0.180, 1.007±0.150, 1.008±0.153, respectively in the normal control group ( t=12.540, 6.309, 13.710, 3.078; all at P<0.05). Conclusions:After the mouse fibroblasts were interfered with ELF-EMFs, the expression levels of MAPK12, NTRK3, AGTR2, VEGF and other genes are significantly up-regulated, which mainly involve neurotrophin signaling pathway, renin-angiotensin system and other pathways.These genes and pathways may be the main way that ELF-EMFs affect fibroblasts.
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Introducción: La enfermedad cerebrovascular constituye un importante problema de salud a nivel mundial. En la actualidad se desarrollan investigaciones científicas dedicadas al estudio de los efectos del campo magnético de frecuencia extremadamente baja para su tratamiento. No es suficientemente clara la información acerca de su inocuidad en las dosis estudiadas. Objetivo: Estudiar la seguridad de la aplicación del campo magnético de frecuencia extremadamente baja a nivel del sistema nervioso central a través de un estudio toxicológico a dosis aguda, repetida y ensayo de micronúcleos en médula ósea. Métodos: Se conformaron tres grupos experimentales con ratas Sprague Dawley Cenp:SPRD jóvenes y sanas para los experimentos de toxicidad y ratones CENP: NMRI para la evaluación mutagénica. Se utilizaron controles negativos no tratados. En el ensayo de micronúcleos se incorporó un grupo control positivo al que se administró Ciclofosfamida por vía intraperitoneal. Se aplicó un campo magnético no homogéneo con niveles de inducción magnética de 6,5 y 15 mT, tomando como referencia el valor máximo sobre la superficie de la bobina. Para la aplicación del campo magnético la bobina estimuladora se colocó sobre la cabeza asegurando la exposición completa del encéfalo. Resultados: En ninguno de los ensayos se detectaron signos de toxicidad. Se comprobó así mismo que no se indujeron efectos genotóxicos ni citotóxicos sobre las células somáticas. Conclusiones: El tratamiento con campo magnético de frecuencia extremadamente baja a nivel del sistema nervioso central en las condiciones experimentales y dosis estudiadas es seguro(AU)
Introduction: Stroke is a major health problem all over the world. Nowadays are developed scientific researches devoted to the study of extremely low frequency magnetic field effects over this illness. The information about it safety is unclear yet. Objective: To study the safety of extremely low frequency magnetic field applied at central nervous system level wasby means ofa toxicological assay (Acute, repeated doses and micronucleus in bone marrow assay) Methods: Three experimental groups were made with Sprague Dawley Cenp: SPRD young and healthy rats for toxicity experiments and CENP: NMRI mice for mutagen evaluation. Untreated negative controls were used. In the micronucleus assay, an additional positive control group was included. This group received Cyclophosphamide by intraperitoneal administration. Was applied a non-homogenousmagnetic fieldof 6,5 and 15 mT, taken as reference the maximum value over the coil surface. The coil was positioned over the head, ensuring full exposure of brain to magnetic field. Results : In none of trials were detected any sign of toxicity. It was also found no genotoxic or cytotoxic effects induced on somatic cells. Conclusions : These results indicated the safety of treatmentwith extremely low frequency magnetic field at central nervous system level for experimental conditions and doses studied(AU)
Subject(s)
Animals , Cerebrovascular Disorders/therapy , Magnetic Field Therapy/methods , Toxicological Symptoms/toxicity , Rats, Sprague-Dawley , Neuroprotection , Mutagenicity Tests/methodsABSTRACT
Oective: To discuss the effects of extremely low frequency electromagnetic fields (ELF-EMF) exposure on the function and morphology of liver, kidney and spleen of the SD rats, and to clarify the mechanism of radiation damage of ELF-EMF. Methods: Twenty male SD rats were randomly divided into exposure group and control group (n=10). The rats in exposure group were exposed in an ELF-EMF device with a magnetic induction of 0. IT and a frequency of 50 Hz; the exposure was conducted for 8 h per day for 30 d. The rats in control group didn' t receive any treatment. After exposure for 30 d, the serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), urea nitrogen (UN), creatinine (Cr) of the rats in two groups were detected. HE staining was used to detect the morphology of the liver, kidney, spleen tissues of the rats in two groups. Results: Compared with control group, the serum levels of ALT, AST, UN, and Cr of the rats in exposure group were increased (P<0. 05). In exposure group, the dilatation and congestion were found in the central veios of liver and hepatic sinusoids, glomeruli and interstitial capillaries of kidney, and insinusoids of spleen of the rats; part of the hepatocytes showed necrosis. There was no abnormality morphology in the liver, kidney, and spleen tissues of the rats in control group. Conclusion: Exposure to ELF-EMF (0.1 T, 50 Hz) can affect the function and structures of liver, kidney and spleen tissues of the SD rats, and its mechanism may be related to oxidative stress induced by ELF-EMF.
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Introduction: Chronic exposure of non-ionizing extremely low-frequency magnetic fields (ELF-EMF) is considered as a health hazard due to its adverse effects on human body such as generation of any type of cancer. Stem cells are appropriate models to assess the effects of ELF-EMF on other cell lines and human beings. Materials and methods: Adipose tissue has been known as source of multi potent stromal human mesenchymal stem cells (MSCs) which can be obtained in less invasive method and in large amounts; so adipose-derived stem cells (ADSCs) were used in this study. Effect of ELF-EMF (intensities of 0.5 and 1 mT and 50 Hz) on proliferation rate of hADSCs was assessed in 20 and 40 min per day for 7 days. Trypan blue assay was performed to assess cell proliferation rate. Result: The results shown that 0.5 and 1 mT magnetic fields can promote the proliferation rate of adipose derived hMSCs according to the duration of exposure. Conclusion: These outcomes could approve the effect of ELF-EMF on cancer induction; although the effective mechanisms in this process are still unknown.
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Objective@#To investigate the influence of extremely low-frequency magnetic field on periodical expression of cryptochrome (Cry) gene in mouse embryonic fibroblast NIH3T3 cells.@*Methods@#The NIH3T3 cells were divided into magnetic field group and sham-exposure group. The NIH3T3 cells in the magnetic field group were stimulated by horse serum and then exposed to an extremely low-frequency magnetic field (50 Hz and 0.3 mT) for 48 hours, and those in the sham-exposure group were also stimulated by horse serum and then exposed to a coil for 48 hours. The NIH3T3 cells were collected, total RNA was extracted, and cDNA was obtained via reverse transcription. Real-time fluorescent quantitative RT-PCR was used to measure the changes in transcription cycles of Cry and Period genes in both groups.@*Results@#There was no significant difference in the proliferation rate at 0, 12, 24, and 48 hours of exposure between the two groups (P>0.05) . Both sham-exposure group and magnetic field group showed a rhythmic change in the expression of Cry gene, and compared with the sham-exposure group, the magnetic field group had a significantly shortened circadian rhythm of Cry gene in NIH3T3 cells (t=2.57, P<0.05) . Both groups had rhythmic and periodical expression of Period gene and there was no significant difference between the two groups (t=0.70, P>0.05) .@*Conclusion@#Extremely low-frequency magnetic field can significantly shorten the circadian rhythm of Cry gene in mouse embryonic fibroblasts, while there is no significant change in the circadian rhythm of Period gene.
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Melanogenesis is the biological process that results in the synthesis of skin pigment of melanin and it has various functions in living systems and is synthesized by the melanosome within the melanocytes. A variety of physical treatments are used to promote melanin production in the melanocytes for pigmentation control. The purpose of this study was to evaluate the intensity-dependent effect of extremely low-frequency electromagnetic fields (ELF-EMFs) on melanogenesis by melanocytes in vitro. Melanocytes were exposed to ELF-EMFs at a frequency of 50 Hz and at intensities in the range of 0.5–20 G over 4 days. The results of lactate dehydrogenase assay showed that there were no significant differences between cells exposed to 0.5 G or 2 G groups and the controls. The melanin contents increased 1.2–1.5-fold in cells exposed to ELF-EMFs and tyrosinase activity increased 1.3-fold in cells exposed to ELF-EMFs, relative to the controls. Also, exposure to ELF-EMFs was associated with activation in cyclic-AMP response element binding protein and microphthalmia-associated transcription factor (MITF) was up-regulated. Up-regulation of MITF induces the expression of melanogenesis-related markers, such as tyrosinase, tyrosinase-related protein (TRP)-1, TRP-2. In conclusion, the present study showed that the exposure to ELF-EMFs at low intensities can stimulate melanogenesis in melanocyte, and these results may be used to a therapeutic devices for inducing repigmentation in vitiligo patients.
Subject(s)
Humans , Biological Phenomena , Carrier Proteins , Electromagnetic Fields , In Vitro Techniques , L-Lactate Dehydrogenase , Magnets , Melanins , Melanocytes , Melanosomes , Microphthalmia-Associated Transcription Factor , Monophenol Monooxygenase , Pigmentation , Response Elements , Skin , Up-Regulation , VitiligoABSTRACT
This study was aimed to observe that extremely low frequency magnetic field (ELF-MF) may be relevant to changes of major neurotransmitters in rat brain. After the exposure to ELF-MF (60 Hz, 2.0 mT) for 2 or 5 days, we measured the levels of biogenic amines and their metabolites, amino acid neurotransmitters and nitric oxide (NO) in the cortex, striatum, thalamus, cerebellum and hippocampus. The exposure of ELF-MF for 2 or 5 days produced significant differences in norepinephrine and vanillyl mandelic acid in the striatum, thalamus, cerebellum and hippocampus. Significant increases in the levels of serotonin and 5-hydroxyindoleacetic acid were also observed in the striatum, thalamus or hippocampus. ELF-MF significantly increased the concentration of dopamine in the thalamus. ELF-MF tended to increase the levels of amino acid neurotransmitters such as glutamine, glycine and gamma -aminobutyric acid in the striatum and thalamus, whereas it decreased the levels in the cortex, cerebellum and hippocampus. ELF-MF significantly increased NO concentration in the striatum, thalamus and hippocampus. The present study has demonstrated that exposure to ELF-MFs may evoke the changes in the levels of biogenic amines, amino acid and NO in the brain although the extent and property vary with the brain areas. However, the mechanisms remain further to be characterized.
Subject(s)
Animals , Rats , Biogenic Amines , Brain , Cerebellum , Dopamine , Glutamine , Glycine , Hippocampus , Magnetic Fields , Neurotransmitter Agents , Nitric Oxide , Norepinephrine , Serotonin , ThalamusABSTRACT
The aim of the present study was to assess whether exposure to the combination of an extremely low frequency magnetic field (ELF-MF; 60 Hz, 1 mT or 2 mT) with a stress factor, such as ionizing radiation (IR) or H2O2, results in genomic instability in non-tumorigenic human lung epithelial L132 cells. To this end, the percentages of G2/M-arrested cells and aneuploid cells were examined. Exposure to 0.5 Gy IR or 0.05 mM H2O2 for 9 h resulted in the highest levels of aneuploidy; however, no cells were observed in the subG1 phase, which indicated the absence of apoptotic cell death. Exposure to an ELF-MF alone (1 mT or 2 mT) did not affect the percentages of G2/M-arrested cells, aneuploid cells, or the populations of cells in the subG1 phase. Moreover, when cells were exposed to a 1 mT or 2 mT ELF-MF in combination with IR (0.5 Gy) or H2O2 (0.05 mM), the ELF-MF did not further increase the percentages of G2/M-arrested cells or aneuploid cells. These results suggest that ELF-MFs alone do not induce either G2/M arrest or aneuploidy, even when administered in combination with different stressors.
Subject(s)
Humans , Aneuploidy , Cell Cycle , Cell Death , Electromagnetic Fields , Epithelial Cells , Genomic Instability , Hydrogen Peroxide , Lung , Magnetic Fields , Radiation, IonizingABSTRACT
En varios asentamientos del país se han construido viviendas Petrocasas de policloruro de vinilo, relleno con hormigón sobre balsa y cubierta de lámina de aluminio revestida de papel asfalto por ambas caras. El policloruro de vinilo como material de construcción resulta controversial en relación a sus efectos en la salud. Con el objetivo de caracterizar desde el punto de vista sanitario el ambiente físico en viviendas Petrocasas de Cienfuegos, fue conducido un estudio descriptivo en dos semanas seleccionadas de las estaciones seca y húmeda de 2008 y 2009. Se monitoreó factores de riesgo físico en una muestra de 6 viviendas seleccionadas según la opinión de expertos, del total de las 104 viviendas del asentamiento según su ubicación en las filas de viviendas: centro, culata de fila y fachada. Se estudió el ruido, componente magnético del campo electromagnético de baja frecuencia, iluminación natural, artificial, microclima y penetración del viento. La evaluación del monitoreo se efectuó por descriptores estadísticos, modelos de regresión, varianza y espectro de potencia bivariado con los paquetes estadísticos: SPSS v. 17,0 y Statistica v. 8,0. Durante la estación seca, la temperatura del aire es mayor en la habitación principal de viviendas con fachada al sur. En ambas estaciones, las temperaturas y humedades relativas de las viviendas son más altas que en la intemperie. Las cubiertas y paredes muestran calentamientos ante el asoleamiento. Los coeficientes de iluminación natural presentan elevadas reflexiones. Los valores del campo electromagnético son bajos. En la estación seca los niveles sonoros reflejan una contaminación acústica moderada. Concluimos que el microclima en el interior de las viviendas durante el día es inconfortable(AU)
Petrohouses have been built in several villages in the country. These houses are made of polyvinyl chloride, filled with raft concrete and covered with aluminum sheets coated with asphalt paper on both sides. The health effects of polyvinyl chloride as a construction material is a matter of controversy. With the purpose of carrying out a health characterization of the physical environment in Cienfuegos petrohouses, a descriptive study was conducted during two weeks selected from the dry and wet seasons of 2008 and 2009. Physical risk factors were monitored in a sample of 6 houses selected on the basis of expert opinion, of the total 104 houses in the village, according to their location in the rows: front, mid and end positions. The variables studied were noise, magnetic component of the low frequency electromagnetic field, natural and artificial lighting, microclimate and wind penetration. Monitoring was evaluated with statistical descriptors, regression models, variance and bivariate power spectrum, with the statistical software SPSS v. 17.0 and Statistica v. 8.0. In the dry season, air temperature is higher in the main room of houses with facades facing the south. In both seasons, temperature and relative humidity values are higher inside the houses than outside. Covers and walls heat up when hit by the sun. Natural lighting coefficients show high reflection values. Electromagnetic field values are low. In the dry season, sound levels show moderate acoustic contamination. It is concluded that the microclimate inside houses during the day is uncomfortable(AU)
Subject(s)
Humans , Vinyl Compounds/adverse effects , PVC Pipes/adverse effects , Risk Assessment/statistics & numerical data , Construction Materials/adverse effects , Housing , Environment , /methods , MicroclimateABSTRACT
Aims: This report is the first study of the possible relationship between extremely low frequency (50-60 Hz, ELF) magnetic field (MF) exposure and severe cognitive dysfunction. Earlier studies investigated the relationships between MF occupational exposure and Alzheimer’s disease (AD) or dementia. These studies had mixed results, depending upon whether the diagnosis of AD or dementia was performed by experts and upon the methodology used to classify MF exposure. Study Design: Population-based case-control. Place and Duration of Study: Neurology and Preventive Medicine, Keck School of Medicine, University of Southern California, 2 years. Methodology: The study population consisted of 3050 Mexican Americans, aged 65+, enrolled in Phase 1 of the Hispanic Established Population for the Epidemiologic Study of the Elderly (H-EPESE) study. Mini-Mental State Exam (MMSE) results, primary occupational history, and other data were collected. Severe cognitive dysfunction was defined as an MMSE score below 10. The MF exposure methodology developed and used in earlier studies was used. Results: Univariate odds ratios (OR) were 3.4 (P< .03; 95% CI: 1.3-8.9) for high and 1.7 (P=.27; 95% CI: 0.7-4.1) for medium or high (M/H) MF occupations. In multivariate main effects models, the results were similar. When interaction terms were allowed in the models, the interactions between M/H or high occupational MF exposure and smoking history or age group were statistically significant, depending upon whether two (65-74, 75+) or three (65-74, 75-84, 85+) age groups were considered, respectively. When the analyses were limited to subjects aged 75+, the interactions between M/H or high MF occupations and a positive smoking history were statistically significant. Conclusion: The results of this study indicate that working in an occupation with high or M/H MF exposure may increase the risk of severe cognitive dysfunction. Smoking and older age may increase the deleterious effect of MF exposure.
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Objective To study the combined effect of extremely low frequency electromagnetic fields ( ELF-EMF ) exposure (50 Hz and 3 mT) and high temperature exposure on hsp22 and hsp26 expression in Drosophila melanogaster. Methods Under the conditions of 50 Hz and 3 mT ELF-EMF,the male and female D.melanogaster was separately exposed for 2 h at 25℃, 27.5℃, 30℃, 32.5℃,and 35℃, respectively.The death rate, exercise capacity and the hsp22 and hsp26 expression levels of D.melanogaster were detected after exposure;or at 25℃and 35℃at 2 h, 4 h, 8 h, and 24 h, respectively.The hsp22 and hsp26 expression levels of D.melanogaster were tested after exposure .Results After exposure for 2 h at 25℃, 27.5℃, 30℃, 32.5℃, and 35℃, temperature had a significant effect (P0.05).After exposure for 2 h at 25℃, 27.5℃, 30℃, 32.5℃, and 35℃, the hsp22 and hsp26 expression levels of D.melanogaster were significantly impacted(P<0.01) by gender, temperature, ELF-EMF and exposure time, and tem-perature was the most important factor .Gender, temperature, ELF-EMF and exposure time had some interaction with the results.Conclusion ELF-EMF can influence the expression levels of hsp22 and hsp26.ELF-EMF exposure contributes to heat tolerance in D.melanogaster through accelerated expression of hsp22 and hsp26.
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<p><b>OBJECTIVE</b>To investigate the bioeffects of extremely low frequency (ELF) magnetic field (MF) (50 Hz, 400 μT) and magnetic nanoparticles (MNPs) via cytotoxicity and apoptosis assays on PC12 cells.</p><p><b>METHODS</b>MNPs modified by SiO₂ (MNP-SiO₂) were characterized by transmission electron microscopy (TEM), dynamic light scattering and hysteresis loop measurement. PC12 cells were administrated with MNP-SiO2 with or without MF exposure for 48 h. Cytotoxicity and apoptosis were evaluated with MTT assay and annexin V-FITC/PI staining, respectively. The morphology and uptake of MNP-SiO₂ were determined by TEM. MF simulation was performed by Ansoft Maxwell based on the finite element method.</p><p><b>RESULTS</b>MNP-SiO₂ were identified as ~20 nm (diameter) ferromagnetic particles. MNP-SiO₂ reduced cell viability in a dose-dependent manner. MF also reduced cell viability with increasing concentrations of MNP-SiO₂. MNP-SiO₂ alone did not cause apoptosis in PC12 cells; instead, the proportion of apoptotic cells increased significantly under MF exposure and increasing doses of MNP-SiO₂. MNP-SiO₂ could be ingested and then cause a slight change in cell morphology.</p><p><b>CONCLUSION</b>Combined exposure of MF and MNP-SiO₂ resulted in remarkable cytotoxicity and increased apoptosis in PC12 cells. The results suggested that MF exposure could strengthen the MF of MNPs, which may enhance the bioeffects of ELF MF.</p>
Subject(s)
Animals , Rats , Apoptosis , Cell Proliferation , Magnetic Fields , Magnetite Nanoparticles , Toxicity , Microscopy, Electron, Transmission , PC12 Cells , Silicon DioxideABSTRACT
The present study was designed to investigate the influence of Extremely low frequency magnetic field (ELF MF) on depression related behavior, and mechanism involved therein. Mice were exposed to ELF MF (50Hz, 10G) 8h/day for 7, 30, 60, 90 and 120 days. Depression was assessed using forced swim test (FST), in which no significant effect was observed on 7t h, 30t h, 60t h, 90t h exposure day. However, depression was observed on 120t h exposure day. It is evident that ELF MF exposure modulates level of nitric oxide (NO); therefore, the level of NO was measured in the regions of brain viz; cortex, striatum, hippocampus and hypothalamus. Results established that ELF MF elevated NO levels in the regions of brain. Furthermore, the implication of NO was assessed by nitric oxide synthase (NOS) inhibitors suggesting the involvement of NO in ELF MF induced depression.
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Objective To calculate the electric field intensity and transmembrane voltage of spherical cells and ellipsoi -dal red blood cells ( RBC) in an extremely low frequency electromagnetic field .Through this calculation , we can provide reference to the search for interaction targets and mechanics between the extremely low frequency electromagnetic field and organisms.Methods The Finite Element Method was used in the numerical computation for the spherical cell model and the ellipsoidal RBC model .Results The electric field intensity of the two types of cells on the cellular membrane was both significantly higher than the applied electric field strength , and the values of the induced field strength and transmembrane voltage varied with the direction of the electric field periodically .Conclusion The cell shape and direction of the applied electric field are not the main determinants of the cellular membrane electric field intensity and the transmembrane voltage compared with electromagnetic parameters .The distribution of the electric field intensity and transmembrane voltage are re-lated to the direction of the applied electric field.
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Se realizó un ensayo clinicoterapéutico aleatorizado y controlado en fase III en 52 pacientes con psoriasis vulgar, atendidos en la consulta de Dermatología del Hospital Clinicoquirúrgico Docente “Dr. Joaquín Castillo Duany” de Santiago de Cuba, del 2005 al 2010, quienes fueron asignados a 2 grupos (de 26 integrantes cada uno): el activo, que fue tratado convencionalmente con pomada cádica a 20 %; yel experimental, al que se le aplicó el campo electromagnético de extremada baja frecuencia, con vistas a determinar la eficacia de este último en los afectados durante los períodos de crisis e intercrisis. La población estudiada fue caracterizada clínicamente mediante un análisis de frecuencias, en tanto, se utilizaron las pruebas de hipótesis para la evaluación de proporciones, cuyas hipótesis nulas se aceptaron con 5 % de error como máximo. En la serie el campo empleado resultó eficaz para tratar la afección en la etapa de crisis y más eficaz que la crema cádica para prolongar la fase de intercrisis, sin producir reacciones adversas, por lo que constituyó una terapéutica alternativa novedosa, que puede ser generalizada en los servicios dermatológicos del país, a fin de mejorar la calidad de vida de los que padecen esa dermatosis.
A controlled and randomized clinical therapeutical assay in phase III was carried out in 52 patients with vulgar psoriasis, who were assisted in the Dermatology department of "Dr. Joaquín Castillo Duany" Clinical Surgical Hospital in Santiago de Cuba, from 2005 to 2010 who were divided into 2 groups (26 members each): the active group which was conventionally treated with 20% cade ointment; and the experimental group, to which the extremely low frequency electromagnetic field was applied, with the objective of determining the effectiveness of this field in those affected during the periods of crisis and intercrisis. The studied population was clinically characterized by means of a frequency analysis, while the hypothesis tests were used for the evaluation of proportions which null hypothesis were accepted with 5 % as maximum error. In the series the used field was effective to treat the disorder during crisis and more effective than the cade ointment to prolong the intercrisis stage, without causing adverse reactions, so that it constituted a new alternative therapy that can be generalized in the dermatological services of the country, in order to improve the life quality of those who suffer that dermatosis.
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BackgroundThe effects of extremely low frequency electromagnetic fields (ELF-EMFs) on public health have attracted wide attentions.The association of the thermal effect of ELF-EMFs with cancer and ocular tissue damage has been of concern.However,the pathological changes of scleral tissue after exposure to ELF-EMFs as well as the relationship between these changes and myopia are still poorly understood.ObjectiveThe present study was to investigate the molecular pathological changes of human fetal scleral fibroblasts (HFSFs) after exposure to ELF-EMFs in vitro and to explore the possible mechanism in the occurrence and development of myopia.MethodsHFSFs were cultured and passaged and then exposed to 50 Hz electromagnetic fields,and HFSFs that did not receive the irradiation of ELF-EMFs were used as the control group.The expression of collagen type Ⅰ (COL1A1 ) mRNA and matrix metalloproteinase-2 (MMP-2) mRNA in cultured HFSFs were detected by real-time qualitative polymerase chain reaction (real-time PCR) under different magnetic field intensites (0,0.1,0.2,0.5,1.0 mT) and different exposure time (0,6,12,24,36,48 hours).Cell proliferation assay of HFSFs was detected by the cell counting kit 8 ( CCK8 ) assay.The expression levels of COL1 A1 and MMP-2 proteins in HFSFs were further confirmed by immunofluorescence staining.Results The expression of COL1A1 mRNA was significantly down-regulated under the exposure of 0.2 mT ELF-EMFs for 6 hours,in comparison with the control group;moreover,it decreased in parallel with the increased of flux density (0.099±0.008 vs.0.050±0.004) (P =0.009 ).The expression of MMP-2mRNA was up-regulated conspicuously after exposure to 0.1 mT ELF-EMFs for 24 hours,and it increased with exposure time in comparison with the control group ( 0.009 ±0.001 vs.0.018±0.003 ) ( P =0.038 ).Proliferation of HFSFs (A450) was inhibited following the exposure to 0.2 mT ELF-EMFs for 24 hours in comparison with the control group (P =0.009 ).The expression of COL1 A1 in the experimental group was decreased,compared with the control group,but the expression of MMP-2 was increased.ConclusionsELF-EMFs inhibit the proliferation of HFSFs and expression of COL1 A1 in HFSFs,which might be one of the reasons for the development of myopia.
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We previously demonstrated that repeated exposure to extremely low frequency magnetic fields (ELF-MF) increases locomotor activity via stimulation of dopaminergic D1 receptor (J. Pharmacol. Sci., 2007;105:367-371). Since it has been demonstrated that activator protein-1 (AP-1) transcription factors, especially 35-kDa fos-related antigen (FRA), play a key role in the neuronal and behavioral adaptation in response to various stimuli, we examined whether repeated ELF-MF exposure induces FRA-immunoreactivity (FRA-IR) in the striatum and nucleus accumbens (striatal complex) of the mice. Repeated exposure to ELF-MF (0.3 or 2.4 mT, 1 h/day, for consecutive fourteen days) significantly induced hyperlocomotor activity and FRA-IR in the striatal complex in a field intensity-dependent manner. ELF-MF-induced FRA-IR lasted for at least 1 year, while locomotor activity returned near control level 3 months after the final exposure to ELF-MF. Pretreatment with SCH23390, a dopaminergic D1 receptor antagonist, but not with sulpiride, a dopaminergic D2 receptor antagonist, significantly attenuated hyperlocomotor activity and FRA-IR induced by ELF-MF. Our results suggest that repeated exposure to ELF-MF leads to prolonged locomotor stimulation and long-term expression of FRA in the striatal complex of the mice via stimulation of dopaminergic D1 receptor.
Subject(s)
Animals , Mice , Benzazepines , Magnetic Fields , Magnetics , Magnets , Motor Activity , Neurons , Nucleus Accumbens , Sulpiride , Transcription Factor AP-1 , Transcription FactorsABSTRACT
The increasingly raised morbidity of hematological malignancies have attracted much attention from scientists and clinicians in recent years, especially the childhood leukemia, It has been demonstrated that extremely low-frequency electromagnetic fields is closely related to pediatric leukemia. The extremely lowfrequency electromagnetic fields might change the size, appearance, quantity, chemical state and energy of cellular biological molecules and induce cascade reaction via effects on cell-to-cell signal transduction, cell proliferation and apoptosis, gene expression and DNA damage, etc, subsequently promote the development of childhood leukemia. This paper overviewed the recent advances of relationship between the extremely lowfrequency electromagnetic fields and childhood leukemia.
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To evaluate the biohazard properties of an extremely low frequency electromagnetic field (ELF-EMF), we explored the physical properties of the ELF-EMF that generates the electric current induction in the secondary coil from the chamber of a primary solenoid coil. We subsequently explored the biological effects of a strong alternating electromagnetic field (EMF), ranging from 730-960 Gauss, on the mouse testis. Mice were exposed to an alternating EMF field induced by a rectangular electric current at 1, 7, 20, 40, and 80 Hertz, for 1, 3, 5, and 7 hours. The mouse testes were examined for proliferative activity and apoptosis using the in situ terminal deoxynucleotidyl transferase (TdT) method and by immunostaining of proliferating cell nuclear antigen (PCNA), respectively. We found that the electric current induction increased in the 6-8 Hertz range, and that exposure to an ELF-EMF induced the apoptosis of mouse spermatocytes. In situ TdT staining was found to be most prominent in 7 Hertz group, and gradually reduced in the 20, 40, and 80 Hertz groups. These data suggest that a strong EMF can induce reproductive cell death within a short time, and the harmful effects of the EMF are maximal at low frequency alternating EMFs.
Subject(s)
Animals , Mice , Apoptosis , Cell Death , DNA Nucleotidylexotransferase , Electromagnetic Fields , Germ Cells , Magnets , Proliferating Cell Nuclear Antigen , Spermatocytes , TestisABSTRACT
Objective To investigate the mechanism of extremely low frequency electromagnetic field (ELF-EMF) and X-ray irradiation on liver carcinoma cell lines BEL-7402. Methods Liver carcinoma cell lines BEL-7402 had been incubated with ELF-EMF (100 Hz, 0.7 mT, 30 min, 3 days) after X-ray irradiation at different doses (0, 2, 4, 6, 8,10 Gy). The cells were observed on morphologic changes with scanning electron microscope. Flow cytometry and gene microarray were used to investigate the mechanism of cell apeptosis. Results ELF-EMF plus X-ray induced apoptosis on BEL-7402 was observed under scanning electron microscope.When X-irradiation was 2, 4, 6, 8 and 10 Gy, the apoptosis ratios of combined group and only X-irradiation group were 10.0%, 14.5%, 4.3%, 5.1%, 7.1% and 0.1%, 8.1%, 0.1%, 0.4%, 2.2% (P < 0.05) on flow cytometry. The result of microarray indicated that 1465 genes were up-regulated and 1108 down*regulated in the ELF-EMF plus X-ray group in comparison with the control group. The change rates of 110 apoptosis related genes were above 2 times, which including 71 up-regulated and 39 down-regulated. Gene microarray showed that ELF-EMF and X-ray irradiation had a mainly effect on different gene of apoptosis paths (CDC25 and CHKI, ATM, p38, PTEN, p53, G1/S, Fas, G2/M, Cell Cycle, Apoptosis and Caspase). The same genes of ELF-EMF plus X-ray group were showed 13 in ELF-EMF group and 42 in X-ray group. Conclusions Apoptosis paths were significantly different between ELF-EMF and X-irradiation. ELF-EMF cooperates with X-irradiation on inducing BEL-7402 cell apoptosis.