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1.
Biomed. environ. sci ; Biomed. environ. sci;(12): 1045-1058, 2023.
Artículo en Inglés | WPRIM | ID: wpr-1007880

RESUMEN

OBJECTIVE@#In this study, the combined effect of two stressors, namely, electromagnetic fields (EMFs) from mobile phones and fructose consumption, on hypothalamic and hepatic master metabolic regulators of the AMPK/SIRT1-UCP2/FOXO1 pathway were elucidated to delineate the underlying molecular mechanisms of insulin resistance.@*METHODS@#Weaned Wistar rats (28 days old) were divided into 4 groups: Normal, Exposure Only (ExpO), Fructose Only (FruO), and Exposure and Fructose (EF). Each group was provided standard laboratory chow ad libitum for 8 weeks . Additionally, the control groups, namely, the Normal and FruO groups, had unrestricted access to drinking water and fructose solution (15%), respectively. Furthermore, the respective treatment groups, namely, the ExpO and EF groups, received EMF exposure (1,760 MHz, 2 h/day x 8 weeks). In early adulthood, mitochondrial function, insulin receptor signaling, and oxidative stress signals in hypothalamic and hepatic tissues were assessed using western blotting and biochemical analysis.@*RESULT@#In the hypothalamic tissue of EF, SIRT1, FOXO 1, p-PI3K, p-AKT, Complex III, UCP2, MnSOD, and catalase expressions and OXPHOS and GSH activities were significantly decreased ( P < 0.05) compared to the Normal, ExpO, and FruO groups. In hepatic tissue of EF, the p-AMPKα, SIRT1, FOXO1, IRS1, p-PI3K, Complex I, II, III, IV, V, UCP2, and MnSOD expressions and the activity of OXPHOS, SOD, catalase, and GSH were significantly reduced compared to the Normal group ( P < 0.05).@*CONCLUSION@#The findings suggest that the combination of EMF exposure and fructose consumption during childhood and adolescence in Wistar rats disrupts the closely interlinked and multi-regulated crosstalk of insulin receptor signals, mitochondrial OXPHOS, and the antioxidant defense system in the hypothalamus and liver.


Asunto(s)
Humanos , Ratas , Animales , Adulto , Ratas Wistar , Fructosa/metabolismo , Catalasa , Receptor de Insulina/metabolismo , Proteínas Quinasas Activadas por AMP/metabolismo , Campos Electromagnéticos/efectos adversos , Sirtuina 1/metabolismo , Teléfono Celular , Fosfatidilinositol 3-Quinasas/metabolismo , Proteína Forkhead Box O1/metabolismo , Proteína Desacopladora 2
2.
Artículo en Inglés | WPRIM | ID: wpr-822699

RESUMEN

@#Studies on the potential effect of EMF exposure on permeability of the blood-brain barrier (BBB) in humans are virtually absent. This study was conducted to study the effect of EMF exposure on pericytes in brain tissues and its effect on oxidative stress level in the blood through total protein and malondialdehyde (MDA). About 16 male rats (Wistar) were used and divided into two groups which were negative control and treatment group. In negative control group, the animals were placed in a solenoid without any EMF exposure for 3 hours daily for 5 days. In the treatment group, the animals were placed in a solenoid with 0.3 mT EMF exposure for the same time duration. On day 3 and day 5, animals were sacrificed and the brain was removed for histological examination while on day 1, day 3 and day 5, the blood was collected for biochemistry analysis. Histological observation showed the presence of morphological changes in the brain tissues of rats that exposed to EMF. Statistical analysis showed that there is no significant decrease in total protein (p>0.05) between negative control group and treatment group. Meanwhile, MDA level in blood showed a significant increase in treatment group (p<0.05) as compared to the negative control group. The result obtained in this study, suggest that the exposure to EMF can cause changes to the morphology of pericytes in brain tissues, and can increase the MDA level in blood of rats.

3.
Artículo en Inglés | WPRIM | ID: wpr-728581

RESUMEN

With the explosive increase in exposure to radiofrequency electromagnetic fields (RF-EMF) emitted by mobile phones, public concerns have grown over the last few decades with regard to the potential effects of EMF exposure on the nervous system in the brain. Many researchers have suggested that RF-EMFs can effect diverse neuronal alterations in the brain, thereby affecting neuronal functions as well as behavior. Previously, we showed that long-term exposure to 835 MHz RF-EMF induces autophagy in the mice brain. In this study, we explore whether short-term exposure to RF-EMF leads to the autophagy pathway in the cerebral cortex and brainstem at 835 MHz with a specific absorption rate (SAR) of 4.0 W/kg for 4 weeks. Increased levels of autophagy genes and proteins such as LC3B-II and Beclin1 were demonstrated and the accumulation of autophagosomes and autolysosomes was observed in cortical neurons whereas apoptosis pathways were up-regulated in the brainstem but not in the cortex following 4 weeks of RF exposure. Taken together, the present study indicates that monthly exposure to RF-EMF induces autophagy in the cerebral cortex and suggests that autophagic degradation in cortical neurons against a stress of 835 MHz RF during 4 weeks could correspond to adaptation to the RF stress environment. However, activation of apoptosis rather than autophagy in the brainstem is suggesting the differential responses to the RF-EMF stresses in the brain system.


Asunto(s)
Animales , Ratones , Absorción , Apoptosis , Autofagia , Encéfalo , Tronco Encefálico , Teléfono Celular , Corteza Cerebral , Campos Electromagnéticos , Sistema Nervioso , Neuronas
4.
Artículo en Inglés | WPRIM | ID: wpr-627246

RESUMEN

The aim of this survey is to investigate whether the Electromagnetic Fields (EMF) emitted from various Air conditioners and Electrical Switch boards at different Labs at the Electrical and Electronic Engineering (EEE) department of Southeast University, Bangladesh,affects the students. There is a standard threshold value recommended by World Health Organization (WHO) for both electric and magnetic fields. Electro-Magnetic Fields commonly known as Non Ionizing Radiation is emitted from high power transmission lines, computer monitor/video display unit, radio waves of different frequencies (extremely low frequency to microwaves), telecommunication, satellite, radar etc. which causes health hazards to living system and environment. There has been no such study performed in Bangladesh. Magnetic Fields around the equipments as well as the threshold values of Electric and Magnetic fields were measured.

5.
Artículo en Inglés | WPRIM | ID: wpr-626765

RESUMEN

The emergence of research about the biological effects of electromagnetic field (EMF) have growing concern among researchers. The aim of this study was to investigate the effects on the brain of rats periodically exposed to 0.1 mT EMF. Total 24 adult male Sprague Dawley rats were subdivided randomly to 4 groups: 2 control groups (C1 6 hours: 6 h/ day for 5 days; C2 20 hours: 20 h/day for 5 days) and 2 treatment groups which exposed to 0.1 mT EMF (T1 6 hours: 6 h/day for 5 days; T2 20 hours: 20 h/day for 5 days). A significant decrease in the pyramidal cell number was higher as the exposure duration to EMF was extended (T1, p<0.05; T2, p<0.001). The total numbers of pyramidal cells for T1 was 15.18 % lower than of the total found in C1; and in concurring to the pattern, the number of pyramidal cells in T2 was 33.54 % lower than the total in C2. Similarly, there was a significant decrease of the Purkinje cell number as the duration exposure to EMF, extended (T1, p<0.05; T2, p<0.001). The total numbers of Purkinje cells for T1 was 11.20 % lower than C1, in T2 was 16.19 % lower than in C2. There were significant differences between the thickness of granular layer and molecular layer in the control groups and treatment groups. We also report a significant difference in the levels of norepinephrine in T2, 10.71 % higher than C2. Cumulatively, these results suggested that exposure to EMF can exert negative effect on rats brains.


Asunto(s)
Campos Electromagnéticos
6.
Artículo en Inglés | WPRIM | ID: wpr-728325

RESUMEN

The effects of extremely low frequency electromagnetic fields (EMF) on intracellular Ca2+ mobilization and cellular function in RBL 2H3 cells were investigated. Exposure to EMF (60 Hz, 0.1 or 1 mT) for 4 or 16 h did not produce any cytotoxic effects in RBL 2H3 cells. Melittin, ionomycin and thapsigargin each dose-dependently increased the intracellular Ca2+ concentration. The increase of intracellular Ca2+ induced by these three agents was not affected by exposure to EMF (60 Hz, 1 mT) for 4 or 16 h in RBL 2H3 cells. To investigate the effect of EMF on exocytosis, we measured beta-hexosaminidase release in RBL 2H3 cells. Basal release of beta-hexosaminidase was 12.3+/-2.3% in RBL 2H3 cells. Exposure to EMF (60 Hz, 0.1 or 1 mT) for 4 or 16 h did not affect the basal or 1 microM melittin-induced beta-hexosaminidase release in RBL 2H3 cells. This study suggests that exposure to EMF (60 Hz, 0.1 or 1 mT), which is the limit of occupational exposure, has no influence on intracellular Ca2+ mobilization and cellular function in RBL 2H3 cells.


Asunto(s)
beta-N-Acetilhexosaminidasas , Campos Electromagnéticos , Exocitosis , Ionomicina , Meliteno , Exposición Profesional , Tapsigargina
7.
Cuad. méd.-soc. (Santiago de Chile) ; 51(4): 187-217, 2011. ilus, tab
Artículo en Español | LILACS | ID: lil-691007

RESUMEN

Los efectos en salud de la radiación electromagnética ionizante son bien conocidos; sin embargo hay menos reconocimiento de los efectos en salud causados por exposición a radiación electromagnética no ionizante. La primera parte del presente trabajo se refiere a los efectos en salud de las radiaciones electromagnéticas no ionizantes, independiente de su origen, puesto que no hay diferencias apreciables entre los efectos producidos por los diversos tipos de radiación electromagnética no ionizante y por lo tanto, son también válidas para aquellas emitidas por la telefonía celular. Se describe una asociación estadísticamente significativa de varias enfermedades a radiación electromagnética de frecuencia baja (ELF) proveniente de tendidos o transformadores de alta tensión, radiación electromagnética ELF del tendido eléctrico domiciliario y de artefactos electrodomésticos, exposición ocupacional a radiación electromagnética principalmente ELF, y radiación electromagnética de radiofrecuencia (RF) proveniente de antenas de transmisión de televisión. A continuación se analizan los efectos ya demostrados de la telefonía celular (los teléfonos y sus antenas repetidoras). Luego se analizan los grados de certeza de un estudio del Estado de California (USA) para relacionar las diversas enfermedades causadas por radiación electromagnética no ionizante. Este estudio confirmó la alta o mediana probabilidad de una relación causa-efecto de la radiación electromagnética con las siguientes enfermedades: leucemia en adultos y niños, cáncer cerebral en adultos y niños, cáncer de mama femenino y masculino, abortos espontáneos, suicidio, enfermedad de Alzheimer, esclerosis lateral amiotrófica y enfermedades cardiovasculares incluyendo infarto del miocardio. Se describen cuales son estas enfermedades de acuerdo al origen de estas radiaciones y se analizan cuales pueden ser los mecanismos biológicos que determinan la génesis de éstas...


The health effects of ionizing electromagnetic radiation are well known; neverthless there exist less recognition on the health effects of exposure to non-ionizing electromagnetic radiation. The first part of the present report refers to health effects of non-ionizing electromagnetic radiation, independently of its origin, since there are not important differences among effects caused by the different kind of non-ionizing radiations, therefore, they are valid for those emmited by the mobile telephony. A statistically significant association is described among various diseases and extremely low frequency electromagnetic radiation (ELF) from high tension electric conductors or transformers, intradomiciliary electric lines or electrodomestic appliances, occupational exposure to electromagnetic fields, mainly ELF, and radiofrequency (RF) electromagnetic radiation from television transmission. Already demonstrated effects of mobile telephony (cellular telephones and their antenas). The degrees of certainty from a study of the State of California (USA) is analyzed to relate various diseases caused by non-ionizing radiation. This study confirmed high or moderate probability of a cause-effect relationship for adult and child leukemia, brain cancer in adults and children, female and male breast cancer, spontaneous abortions, suicide, Alzheimer disease, amiotrophic lateral sclerosis and cardiovascular diseases including myocardial infarction. Various diseases are related to the different origin of the radiation, and the biological mechanisms involved in disease generation are analyzed. Research performed in the USSR and afterwards in Russia on health effects of mobile telephony are summarized, these investigations originated the regulation in this country and afterwards in West Europe, and influenced the decisions of WHO on its carcinogenicity...


Asunto(s)
Humanos , Enfermedad de Alzheimer/etiología , Enfermedades Cardiovasculares/etiología , Neoplasias Inducidas por Radiación/etiología , Radiación no Ionizante/efectos adversos , Aborto Espontáneo/etiología , Chile , Campos Electromagnéticos/efectos adversos , Legislación Ambiental , Leucemia/etiología , Microondas , Exposición Profesional , Ondas de Radio/efectos adversos , Límite Permisible de Riesgos Laborales , Televisión , Teléfono Celular
8.
Artículo en Inglés | WPRIM | ID: wpr-727387

RESUMEN

This study was conducted to investigate the effects of extremely low frequency electromagnetic fields (EMF) on signal pathway in plasma membrane of cultured cells (RAW 264.7 cells and RBL 2H3 cells), by measuring the activity of phospholipase A2 (PLA2), phospholipase C (PLC) and phospholipase D (PLD). The cells were exposed to the EMF (60 Hz, 0.1 or 1 mT) for 4 or 16 h. The basal and 0.5 microM melittin-induced arachidonic acid release was not affected by EMF in both cells. In cell-free PLA2 assay, we failed to observe the change of cPLA2 and sPLA2 activity. Also both PLC and PLD activities did not show any change in the two cell lines exposed to EMF. This study suggests that the exposure condition of EMF (60 Hz, 0.1 or 1 mT) which is 2.4 fold higher than the limit of occupational exposure does not induce phospholipases-associated signal pathway in RAW 264.7 cells and RBL 2H3 cells.


Asunto(s)
Ácido Araquidónico , Línea Celular , Membrana Celular , Células Cultivadas , Campos Electromagnéticos , Imanes , Exposición Profesional , Fosfolipasa D , Fosfolipasas , Fosfolipasas A2 , Piridoxal , Transducción de Señal , Fosfolipasas de Tipo C
9.
Artículo en Coreano | WPRIM | ID: wpr-132053

RESUMEN

STUDY DESIGN: An in vitro experiment. OBJECTIVES: To assess the effect of pulsed sinusoidal EMF on human intervertebral disc (IVD) cells. LITERATURE REVIEW SUMMARY: Electromagnetic field (EMF) is known to modify some relevant physiological parameters of cells cultured in vitro, such as proliferation, synthesis, secretion of growth factors and transcription. EMF induces bone formation in delayed, non union and spinal fusion models. Also, the exposure of EMF has been shown to protect against the hazardous effect of smoking in the rabbit IVD. MATERIALS AND METHODS: Human IVD cells were three-dimensionally cultured in alginate beads and exposed to a 650 omega, 1.8millitesla magnetic flux density, 60Hz sinusoidal wave of EMF. The cultures were divided into the control and EMF groups, with various exposure times. The cytotoxicity, and DNA and proteoglycan syntheses were measured by the MTT assay, and [3H]-thymidine and [35S]-sulfate incorporation, respectively. RT-PCRs were performed for aggrecan, and collagen types I and II mRNA expressions. RESULTS: There was no recognizable cytotoxicity in the EMF group, but cellular proliferation was stimulated (p<0.05). Newly synthesized proteoglycan, normalized by DNA synthesis, was decreased in the EMF group (p<0.05) as were the expressions of aggrecan (48hour exposure) and type II collagen (72 hours exposure) mRNA compared to the control group. CONCLUSIONS: EMF seems to be hazardous in the synthesis of the chondrogenic matrix, while marginally beneficial in the cellular proliferation of human IVD cells.


Asunto(s)
Humanos , Agrecanos , Proliferación Celular , Colágeno , Colágeno Tipo II , ADN , Campos Electromagnéticos , Péptidos y Proteínas de Señalización Intercelular , Disco Intervertebral , Imanes , Osteogénesis , Proteoglicanos , ARN Mensajero , Humo , Fumar , Fusión Vertebral
10.
Artículo en Coreano | WPRIM | ID: wpr-132056

RESUMEN

STUDY DESIGN: An in vitro experiment. OBJECTIVES: To assess the effect of pulsed sinusoidal EMF on human intervertebral disc (IVD) cells. LITERATURE REVIEW SUMMARY: Electromagnetic field (EMF) is known to modify some relevant physiological parameters of cells cultured in vitro, such as proliferation, synthesis, secretion of growth factors and transcription. EMF induces bone formation in delayed, non union and spinal fusion models. Also, the exposure of EMF has been shown to protect against the hazardous effect of smoking in the rabbit IVD. MATERIALS AND METHODS: Human IVD cells were three-dimensionally cultured in alginate beads and exposed to a 650 omega, 1.8millitesla magnetic flux density, 60Hz sinusoidal wave of EMF. The cultures were divided into the control and EMF groups, with various exposure times. The cytotoxicity, and DNA and proteoglycan syntheses were measured by the MTT assay, and [3H]-thymidine and [35S]-sulfate incorporation, respectively. RT-PCRs were performed for aggrecan, and collagen types I and II mRNA expressions. RESULTS: There was no recognizable cytotoxicity in the EMF group, but cellular proliferation was stimulated (p<0.05). Newly synthesized proteoglycan, normalized by DNA synthesis, was decreased in the EMF group (p<0.05) as were the expressions of aggrecan (48hour exposure) and type II collagen (72 hours exposure) mRNA compared to the control group. CONCLUSIONS: EMF seems to be hazardous in the synthesis of the chondrogenic matrix, while marginally beneficial in the cellular proliferation of human IVD cells.


Asunto(s)
Humanos , Agrecanos , Proliferación Celular , Colágeno , Colágeno Tipo II , ADN , Campos Electromagnéticos , Péptidos y Proteínas de Señalización Intercelular , Disco Intervertebral , Imanes , Osteogénesis , Proteoglicanos , ARN Mensajero , Humo , Fumar , Fusión Vertebral
11.
Artículo en Inglés | WPRIM | ID: wpr-284993

RESUMEN

We have reviewed epidemiological studies examining the association between residential exposure to extremely low frequency electric and magnetic fields (ELF-EMF) and childhood leukemia. We have excluded studies focusing on electrical appliances, because it is difficult to consolidate transient exposure from multiple sources and equally difficult to control information bias. We have identified 24 studies of residential exposure to ELF-EMF and childhood leukemia. About half of these studies were reported as positive and the remaining as null. For each of the studies reported as positive, however, one or more sources of bias could not be confidently excluded. Moreover, studies which were methodologically more sound, or benefited from high quality registry data, were more frequently null than other investigations. We conclude that the empirical evidence in support of an association between ELF-EMF and childhood leukemia is weak.

12.
Artículo en Japonés | WPRIM | ID: wpr-361501

RESUMEN

We have reviewed epidemiological studies examining the association between residential exposure to extremely low frequency electric and magnetic fields (ELF-EMF) and childhood leukemia. We have excluded studies focusing on electrical appliances, because it is difficult to consolidate transient exposure from multiple sources and equally difficult to control information bias. We have identified 24 studies of residential exposure to ELF-EMF and childhood leukemia. About half of these studies were reported as positive and the remaining as null. For each of the studies reported as positive, however, one or more sources of bias could not be confidently excluded. Moreover, studies which were methodologically more sound, or benefited from high quality registry data, were more frequently null than other investigations. We conclude that the empirical evidence in support of an association between ELF-EMF and childhood leukemia is weak.


Asunto(s)
Leucemia , Sesgo
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