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1.
Altern Ther Health Med ; 29(8): 75-81, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37678874

RESUMO

Objective: Leukemia is the most prevalent cancer among children and adolescents. This study investigated the potential association between exposure to magnetic fields and the risk of pediatric leukemia. Methods: We conducted a comprehensive search of electronic databases, including Scopus, EMBASE, Cochrane, Web of Science, and Medline, up to December 15, 2022, to identify relevant studies examining the link between childhood leukemia and magnetic field exposure. Results: The first meta-analysis revealed a statistically significant inverse association between pediatric leukemia and magnetic field strengths ranging from 0.4 µT to 0.2 µT, suggesting a reduced risk associated with this range. The second meta-analysis focused on wiring configuration codes and observed a potential link between residential magnetic field exposure and childhood leukemia. Pooled relative risk estimates were 1.52 (95% CI = 1.05-2.04, P = .021) and 1.58 (95% CI = 1.15-2.23, P = .006) for exposure to 24-hour magnetic field measurements, suggesting a possible causal relationship. In the third meta-analysis, the odds ratios for the exposure groups of 0.1 to 0.2 µT, 0.2 to 0.3 µT, 0.3 to 0.4 µT, and 0.4 µT above 0.2 µT were 1.09 (95% confidence interval = 0.82 to 1.43 µT), 1.14 (95% confidence interval = 0.68 to 1.92 µT), and 1.45 (95% confidence interval = 0.87 to 2.37 µT), respectively. In contrast to the findings of the three meta-analyses, there was no evidence of a statistically significant connection between exposure to 0.2 µT and the risk of juvenile leukemia. A further result showed no discernible difference between the two groups of children who lived less than 100 meters from the source of magnetic fields and those who lived closer (OR = 1.33; 95% CI = 0.98-1.73 µT). Conclusions: The collective results of three meta-analyses, encompassing magnetic field strengths ranging from 0.1 µT to 2.38 µT, underscore a statistically significant association between the intensity of magnetic fields and the occurrence of childhood leukemia. However, one specific analysis concluded that no apparent relationship exists between exposure to 0.1 µT and an elevated risk of leukemia development in children.


Assuntos
Leucemia , Neoplasias , Adolescente , Criança , Humanos , Campos Eletromagnéticos/efeitos adversos , Leucemia/epidemiologia , Leucemia/etiologia , Campos Magnéticos , Radiação Eletromagnética , Exposição Ambiental/efeitos adversos , Estudos de Casos e Controles
2.
Electromagn Biol Med ; 42(3): 123-132, 2023 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-37638990

RESUMO

Although there are numerous studies on the health impacts of electromagnetic field (EMF) of mobile phone operation frequency 2100 MHz, the published works present contradicting results. Long-term exposure to mobile phone frequencies has unclear health hazards. Therefore, it is important to investigate the molecular mechanism of possible biological effects in mobile phone exposure and to determine the corresponding biological markers. Towards this end, this study was designed to assess the effect of 200 nM selenium (Se) on cell viability% [trypan blue], cell cycle biomarker [cyclin D1] and the transcription factor [nuclear factor kappa b (NF-κB)] in NIH/3T3 fibroblast cells when exposed to 2100 MHz mobile phone frequency. When 2100 MHz EMF was exposed to NIH/3T3 fibroblast cells, the cell viability% was reduced, whereas cyclin D1 level and NF-kB activity increased. Also we show that Se supplementation decreases the effects of 2100 MHz EMF on these parameters. Although future studies will be required to investigate the biological effects of EMF emitted by mobile phones, the results obtained here provide an insight into the molecular mechanisms and specifically underlying selenium's protective effect against 2100 MHz EMF exposure.


Assuntos
Telefone Celular , Selênio , Biomarcadores , Ciclina D1 , Campos Eletromagnéticos/efeitos adversos , NF-kappa B , Selênio/farmacologia , Animais , Camundongos , Células NIH 3T3
3.
Bioelectromagnetics ; 44(3-4): 77-89, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36999566

RESUMO

The increasing use of nonionizing radiofrequency electromagnetic fields (RF-EMFs) in a wide range of technologies necessitates studies to further understanding of biological effects from exposures to such forms of electromagnetic fields. While previous studies have described mechanisms for cellular changes occurring following exposure to low-intensity RF-EMFs, the role of molecular epigenetics has not been thoroughly investigated. Specifically unresolved is the effect of RF-EMFs on deoxyribonucleic acid (DNA) methylation, which is a powerful epigenetic process, used by cells to regulate gene expression. DNA methylation is dynamic and can be rapidly triggered in response to external stimuli such as exposure to RF-EMFs. In the present study, we performed a global analysis of DNA methylation patterns in human keratinocytes exposed to 900 MHz RF-EMFs for 1 h at a low dose rate (estimated mean specific absorption rate (SAR) < 10 mW/kg). We used a custom system to allow stable exposure of cell cultures to RF-EMFs under biologically relevant conditions (37 °C, 5% CO2 , 95% humidity). We performed whole genome bisulfite sequencing directly following RF-EMF exposure to examine the immediate changes in DNA methylation patterns and identify early differentially methylated genes in RF-EMF-exposed keratinocytes. By correlating global gene expression to whole genome bisulfite sequencing, we identified six common targets that were both differentially methylated and differentially expressed in response to RF-EMF exposure. The results highlight a potential epigenetic role in the cellular response to RF-EMFs. Particularly, the six identified targets may potentially be developed as epigenetic biomarkers for immediate responses to RF-EMF exposure. Bioelectromagnetics. 1-13, © 2023 Bioelectromagnetics Society. This article has been contributed to by U.S. Government employees and their work is in the public domain in the USA.


Assuntos
Metilação de DNA , Campos Eletromagnéticos , Humanos , Campos Eletromagnéticos/efeitos adversos , Queratinócitos , Ondas de Rádio/efeitos adversos
4.
Bioelectromagnetics ; 44(1-2): 17-25, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36786436

RESUMO

Medical Physics Department (Medical School, University of Thessaly) participated in a Greek National EMF research program (EDBM34) with the scope to measure and evaluate radiofrequency (RF) exposure (27-3000 MHz) in areas of sensitive land use. A thousand (1000) measurements were carried out at two "metropolitan locations" (Athens and Thessaloniki: 624 points) and several rest urban/rural locations (376 points). SRM 3006 spectrum analyzer manufactured by Narda Safety Test Solutions was used. The broadband mean electric field in metropolitan areas was 0.41 V/m, while in the rest of Greece was 0.36 V/m. In metropolitan areas, the predominant RF source was the TV and Radio FM signals (36.2% mean contribution to the total RF exposure level). In the rest areas, the predominant source was the systems of the meteorological and military/defensive service (31.1%). The mobile sector contributed 14.9% in metropolitan areas versus 12.2% in the rest of Greece. The predominant mobile source was 900 MHz in both cases (4.5% in metropolitan areas vs. 3.3% in the rest of Greece). The total exposure from all RF sources complied with the International Commission on Non-Ionizing Radiation Protection (ICNIRP) 2020 safety guidelines [ICNIRP, 2020]. The maximum exposure level was 0.129% of the limit for the metropolitan areas vs. 0.110% for the rest of Greece. Nonremarkable differences between metropolitan areas' exposure and the rest of Greece. In most cases, new 5 G antennas will be added to the existing base stations. Thus, the total exposure may be increased, leading to higher safety distances. © 2023 Bioelectromagnetics Society.


Assuntos
Telefone Celular , Campos Eletromagnéticos , Grécia , Campos Eletromagnéticos/efeitos adversos , Exposição Ambiental , Ondas de Rádio/efeitos adversos , Eletricidade
5.
Health Phys ; 124(5): 351-371, 2023 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-36735538

RESUMO

ABSTRACT: The Institute for Electrical and Electronic Engineers (IEEE) and the International Commission on Non-ionizing Radiation Protection (ICNIRP) have established limits for exposures to electromagnetic fields across the 0-300 GHz (non-ionizing) spectrum, including limits on contact currents ( CC ) specified by IEEE for 0-110 MHz (ICNIRP issued a CC "guidance level"). Both sets of limits seek to protect against potentially adverse effects, including aversive electrostimulation at frequencies <100 kHz and excessive heating of tissue at frequencies >100 kHz. For the most part, CC is linked to electric field ( E -field) exposures for an ungrounded person contacting a grounded object, with the short-circuit current ( I SC ) through the contact point (usually the hand) equivalent to the current through the grounded feet of a free-standing person exposed to a vertically polarized E -field. The physical linkage between these two quantities dictates that their respective exposure limits align with one another, which is presently not the case, especially with respect to frequencies from100 kHz to 110 MHz. Here we focus specifically on recommendations for revisions to the IEEE standard, IEEE Std C95.1™-2019 ("IEEE C95.1"), in which the E -field exposure limit ( E -field exposure reference levels, ERL s) >100 kHz induces substantially greater currents than the CC ERL s currently prescribed. The most important scenario deserving of attention concerns finger contact through a 1-cm 2 cross-sectional interface between the skin and a grounded conductor in which the rate of temperature rise in the presence of an E -field ERL can be rapid enough to cause a burn injury. This rate is highly dependent on the moistness/dryness of the skin at the contact point (i.e., its impedance)-a highly variable value-with temperature increasing more rapidly with increasing dryness (greater contact impedance). The two main remedies to alleviate the possibility of injury in this "touch" scenario are to (a) limit the time of finger contact to 1 s in all cases and (b) revise the E -field ERL between 100 kHz and 30 MHz from a "hockey-stick-shaped" curve vs. frequency to a "ramp" across this frequency range. These measures factored in with the real-world prevalence of potentially hazardous scenarios should afford greater protection against adverse outcomes than is presently the case. IEEE C95.1 also specifies limits for grasp contact (15 cm 2 in the palm) and associated wrist heating, plus heating in the ankles from free-standing induction. However, these scenarios are more manageable compared to finger touch due mainly to the comparatively lower rates of tissue heating attributable to the wrist's and ankle's relatively greater cross-sectional area. Recommendations for grasp can thus be dealt with separately. Two identified but unaddressed issues in IEEE C95.1 deserving of further attention are first, the circumstance in which a grounded person contacts an ungrounded object situated in an electric field for which there are countless numbers of scenarios that are not amenable to a single ERL . Second, arcing between an extended limb and E -field-exposed object is perhaps the most hazardous of all scenarios. Both of these scenarios cannot be stereotyped and must be dealt with on a case-by-case basis. Future revisions of IEEE Std C95.1-2019 (and the ICNIRP guidelines) will benefit from improved insight into strategies of affording protection from potentially adverse effects in these circumstances.


Assuntos
Campos Eletromagnéticos , Humanos , Eletricidade , Campos Eletromagnéticos/efeitos adversos , Extremidades , Temperatura
6.
Technol Health Care ; 31(4): 1343-1353, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36641696

RESUMO

BACKGROUND: The pulsed electromagnetic fields (PEMFs) seem effective in increasing bone mineral density and promoting osteogenesis and bone healing. OBJECTIVE: To examine the effect of two different modalities of PEMFs therapy in comparison with the recommended pharmacological treatment on experimental osteoporosis in rats. METHODS: The experimental model of estrogen-deficient osteoporosis induced by ovariectomy was used in this study. The animals were exposed to PEMFs of various frequencies (40 Hz and 25 Hzk), intensities (10 mT and 36.4 µT), lengths of exposure, and the effects were compared with the standard treatment with pamidronate, vitamin D, and calcium supplementation. RESULTS: The application of PEMF40Hz, significantly reduced the osteoporotic bone loss in female rats that were confirmed with biochemical, biomechanical, and histological analyses. These effects were more pronounced than in osteoporotic animals treated with pamidronate, vitamin D, and calcium supplementation. On the contrary, the exposure to PEMF25Hz did not show restorative effects but led to further progression of osteoporosis. CONCLUSION: The exposure to PEMF40Hz, significantly restored osteoporosis and attenuated bone fragility in comparison to the rats exposed to PEMF25Hz or those treated with pamidronate, vitamin D, and calcium supplementation.


Assuntos
Cálcio , Campos Eletromagnéticos , Estrogênios , Osteoporose , Pamidronato , Vitamina D , Animais , Feminino , Ratos , Densidade Óssea/efeitos dos fármacos , Cálcio/farmacologia , Cálcio/uso terapêutico , Campos Eletromagnéticos/efeitos adversos , Estrogênios/deficiência , Osteoporose/tratamento farmacológico , Osteoporose/patologia , Pamidronato/uso terapêutico , Vitamina D/farmacologia , Vitamina D/uso terapêutico , Conservadores da Densidade Óssea/uso terapêutico
7.
Trends Cardiovasc Med ; 33(2): 72-78, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-34678423

RESUMO

In recent years, electromagnetic field (EMF) therapy has gathered much attention for its protective effects on cardiovascular functions. From reviewing the literature, it is evident that exposure to specific EMF spectrums, such as static- and extremely low frequency (ELF)- EMFs, by EMF-generating devices can be considered as a safe method for therapeutic means in various cardiovascular diseases, including heart failure, cardiac arrhythmias, and hypertension. This review article will describe registered patents and non-invasive clinically effective devices that generate EMF to target various cardiovascular diseases based on their mechanism of therapeutic effects.


Assuntos
Doenças Cardiovasculares , Hipertensão , Magnetoterapia , Humanos , Campos Eletromagnéticos/efeitos adversos , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/terapia , Magnetoterapia/efeitos adversos
9.
Bioelectromagnetics ; 43(8): 476-490, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36490205

RESUMO

Extremely low frequency pulsed magnetic fields (MFs) have been increasingly used as an effective method in oral therapy, but its potential impact on health has not been clarified. In this study, we investigated the impact of 10 Hz pulsed MF exposure on primary human gingival fibroblasts (HGFs) derived from eight healthy persons (four males and four females). Cells were exposed to 10 Hz pulsed MFs at 1.0 mT for 24 h. Cell apoptosis, cell cycle progression, intracellular reactive oxygen species levels, DNA damage, and cell proliferation were determined after exposure. The results showed that 10 Hz pulsed MFs exposure have slight effects on cellular apoptosis, cell cycle progression, and DNA damage in primary HGFs from some but not all samples. In addition, no significant effect was found on cell proliferation. © 2022 Bioelectromagnetics Society.


Assuntos
Dano ao DNA , Campos Magnéticos , Masculino , Humanos , Espécies Reativas de Oxigênio/metabolismo , Fibroblastos/metabolismo , Apoptose , Campos Eletromagnéticos/efeitos adversos
10.
J Chem Neuroanat ; 122: 102092, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35364275

RESUMO

Humans are exposed to electromagnetic fields (EMF) from various sources throughout life. Because humans are easily impacted by environmental factors during early development, it is believed that EMF can cause structural and functional changes on the developing brain that may lead to behavioural changes. This paper investigates the impact of EMF exposure and zinc supplementation during the prenatal and postnatal periods on behavioural changes and synaptic proteins in a gender-dependent manner. Pups from four groups of pregnant rats were used: Sham, EMF (5 days/wk, 4 h/day EMF-exposure applied), Sham+Zinc (5 days/wk, 5 mg/kg/day zinc applied) and EMF+Zinc (5 days/wk, 4 h/day EMF-exposure and 5 mg/kg/day zinc applied). EMF exposure and zinc supplementation were initiated from the first day of pregnancy to the 42nd postnatal day. Zinc levels in blood, NLGN3 and SHANK3 levels in hippocampus and amygdala, and synaptic structures in amygdala were examined. Behavioural tests showed that EMF exposure had no effect on social behaviour, but adversely affected activity and exploratory behaviour, and led to increased anxiety formation. Zinc supplementation had a partially positive effect on female, but not male offspring. SHANK3 and NLGN3 proteins were significantly lower in EMF groups, however, no positive effect of zinc supplementation was found. In conclusion, EMF exposure may alter the levels of synaptic proteins in the developing brain, leading to behavioural changes in a gender-dependent manner. Evaluation of zinc supplementation at different doses could be beneficial to prevent or reduce the behavioural and structural effects of EMF.


Assuntos
Campos Eletromagnéticos , Efeitos Tardios da Exposição Pré-Natal , Animais , Campos Eletromagnéticos/efeitos adversos , Feminino , Humanos , Gravidez , Efeitos Tardios da Exposição Pré-Natal/etiologia , Ratos , Ratos Sprague-Dawley , Fatores Sexuais , Zinco/farmacologia
11.
Bioelectromagnetics ; 43(4): 268-277, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35476222

RESUMO

This study aimed to evaluate the effectiveness of using low-level, low-frequency pulsed electromagnetic field (LLLF_PEMF) stimulation to improve atopic dermatitis induced by 2,4-dinitrochlorobenzene (DNCB). Twenty 6-week-old hairless mice were randomly divided into Normal (n = 5), PEMF 15 Hz (n = 5), PEMF 75 Hz (n = 5), and Sham (n = 5) groups. Following the onset of atopic dermatitis symptoms, PEMF groups (15 and 75 Hz) were stimulated with LLLF_PEMF (15 mT) for 8 h per day for 1 week. Sensory evaluation analysis revealed a significant difference between the PEMF 15 Hz group and Sham group (P < 0.05), but these differences were not visually obvious. While both the PEMF and Sham groups had atopic dermatitis lesions, lesion size was significantly smaller in the two PEMF groups than in the Sham group (P < 0.001). Additionally, changes in epithelial thickness because of skin inflammation significantly decreased for both PEMF groups, compared with the Sham group (P < 0.001). In conclusion, these results suggest that PEMF stimulation in vivo triggers electro-chemical reactions that affect immune response. © 2022 Bioelectromagnetics Society.


Assuntos
Dermatite Atópica , Campos Eletromagnéticos , Animais , Camundongos , Dermatite Atópica/terapia , Campos Eletromagnéticos/efeitos adversos
12.
Bioelectromagnetics ; 43(3): 160-173, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35233784

RESUMO

Fetal development is vital in the human lifespan. Therefore, it is essential to characterize exposure by a series of typical environmental magnetic and electromagnetic fields. In particular, there has recently been a sharp increase in the twin birth rate. However, lack of appropriate models has prohibited dosimetric evaluation, restricting characterization of the impact of these environmental factors on twins. The present study developed two whole-body pregnant models of 31 and 32 weeks of gestation with twin fetuses and explored several typical exposure scenarios, including 50-Hz uniform magnetic field exposure, local 125-kHz magnetic field (MF), and 13.56-MHz electromagnetic field exposure, as well as wideband planewave radiofrequency (RF) exposure from 20 to 6000 MHz. Finally, dosimetric results were derived. Compared to the singleton pregnancy with similar weeks of gestation, twin fetuses were overexposed at 50-Hz uniform MF, but they were probably underexposed in the RF scenarios with frequencies for wireless communications. Furthermore, the twin fetuses manifested large dosimetric variability compared to the singleton, which was attributed to the incident direction and fetal position. Based on the analysis, the dosimetric results over the entire gestation period were estimated. The results can be helpful to estimate the risk of twin-fetal exposure to electromagnetic fields and examine the conservativeness of the international guidelines.© 2022 Bioelectromagnetics Society.


Assuntos
Campos Eletromagnéticos , Gravidez de Gêmeos , Campos Eletromagnéticos/efeitos adversos , Exposição Ambiental , Feminino , Feto , Humanos , Campos Magnéticos , Gravidez
13.
Am J Mens Health ; 16(1): 15579883221074821, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35172663

RESUMO

The present study aims to investigate the effects of using the supplementation of vitamin E and Omega 3 fatty acids on reproductive indices among workers in an automobile parts manufacturing plant. The effect of exposure to electromagnetic fields on certain sex hormones and sperm parameters will also be assessed. The participants were deployed into four groups as per the double-blind block randomization method. Semen parameters and sex hormones of the participants were analyzed before and after 3-month consumption of supplements. The level of workers' exposure to low-frequency magnetic and electrical fields was measured through the recommendation of National Institute for Occupational Safety and Health. Univariate analysis of variance indicated that exposure to electric fields had a statistically significant effect on sperm count, morphology, and motility. The simultaneous consumption of vitamin E + Omega 3 had a statistically significant effect on sperm morphology and motility.


Assuntos
Ácidos Graxos Ômega-3 , Vitamina E , Campos Eletromagnéticos/efeitos adversos , Ácidos Graxos Ômega-3/farmacologia , Humanos , Masculino , Saúde Reprodutiva , Sêmen , Estados Unidos , Vitamina E/farmacologia
14.
Bioelectromagnetics ; 43(2): 69-80, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35005795

RESUMO

In pediatric magnetic resonance imaging (MRI), infants are exposed to rapid, time-varying gradient magnetic fields, leading to electric fields induced in the body of infants and potential safety risks (e.g. peripheral nerve stimulation). In this numerical study, the in situ electric fields in infants induced by small-sized gradient coils for a 1.5 T MRI scanner were evaluated. The gradient coil set was specially designed for the efficient imaging of infants within a small-bore (baby) scanner. The magnetic flux density and induced electric fields by the small x, y, z gradient coils in an infant model (8-week-old with a mass of 4.3 kg) were computed using the scalar potential finite differences method. The gradient coils were driven by a 1 kHz sinusoidal waveform and also a trapezoidal waveform with a 250 µs rise time. The model was placed at different scan positions, including the head area (position I), chest area (position II), and body center (position III). It was found that the induced electric fields in most tissues exceeded the basic restrictions of the ICNIRP 2010 guidelines for both waveforms. The electric fields were similar in the region of interest for all coil types and model positions but different outside the imaging region. The y-coil induced larger electric fields compared with the x- and z- coils. Bioelectromagnetics. 43:69-80, 2022. © 2021 Bioelectromagnetics Society.


Assuntos
Campos Magnéticos , Imageamento por Ressonância Magnética , Criança , Eletricidade , Campos Eletromagnéticos/efeitos adversos , Humanos , Lactente , Imageamento por Ressonância Magnética/efeitos adversos
15.
Bioelectromagnetics ; 43(2): 106-118, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35066900

RESUMO

Numerous studies have shown that radiofrequency electromagnetic radiation (RF-EMR) may negatively affect human health. We detected the effect of 3500 MHz RF-EMR on anxiety-like behavior and the auditory cortex (ACx) in guinea pigs. Forty male guinea pigs were randomly divided into four groups and exposed to a continuous wave of 3500 MHz RF-EMF at an average specific absorption rate (SAR) of 0, 2, 4, or 10 W/kg for 72 h. After exposure, malondialdehyde (MDA) levels, antioxidant enzyme activity, anxiety-like behavior, hearing thresholds, cell ultrastructure, and apoptosis were detected. Our results revealed that hearing thresholds and basic indexes of animal behavior did not change significantly after exposure (P > 0.05). However, the MDA levels of ACx were increased (P < 0.05), and catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GSH-px) activities were decreased (P < 0.05) in the exposure groups compared to the sham group. Ultrastructural changes of ACx, including swollen mitochondria and layered myelin sheaths, were observed. Cytochrome-c relocalization, caspase-9, and cleaved caspase-3 activation were detected in the exposure groups. In conclusion, these results suggest that oxidative stress is an important mechanism underlying the biological effects of RF-EMR, which can induce ultrastructural damage to the ACx and cell apoptosis through a mitochondria-dependent mechanism. Moreover, oxidative stress, apoptosis induction and ultrastructural damage increase in a SAR-dependent manner. However, RF-EMR does not increase hearing thresholds or induce anxiety. Bioelectromagnetics. 43:106-118, 2022. © 2021 Bioelectromagnetics Society.


Assuntos
Córtex Auditivo , Telefone Celular , Animais , Antioxidantes/metabolismo , Ansiedade/etiologia , Córtex Auditivo/metabolismo , Campos Eletromagnéticos/efeitos adversos , Radiação Eletromagnética , Cobaias , Masculino , Estresse Oxidativo
16.
Electromagn Biol Med ; 41(1): 93-100, 2022 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-34994293

RESUMO

The use of mobile phones is becoming widespread with the development of technology, and as a result, its effects on human health are becoming more and more important every day. Studies have reported that the electromagnetic field (EMF) emitted by mobile phones may have adverse effects on the biological systems. In order to evaluate the effect of zinc (Zn) on C3H cancer fibroblast cells exposed to 2100 MHz EMF, we analyzed cell viability%, nuclear factor kappa b (NF-κB) and DNA methyltransferase (DNMT) activities. Cells were divided to following groups: Control, sham control, 2100 MHz EMF, 50 µM Zn + 2100 MHz EMF, 100 µM Zn + 2100 MHz EMF, and 200 µM Zn + 2100 MHz EMF for 2 h. We measurement cell viability, NF-κB and DNMT activities. There was increased cell viability % in the 2100 MHz EMF group compared to the control group, while the cell viability % was decreased in the 50, 100 and 200 µM Zn + 2100 MHz EMF groups compared to 2100 MHz EMF. NF-κB and DNMT activities were a significant increase in the 2100 MHz EMF group compared to the control group, although were statistically decreased in the 50, 100 and 200 µM Zn + 2100 MHz EMF groups compared to the 2100 MHz EMF group. Our results demonstrate that 2100 MHz EMF exposure in cancer fibroblast cells induce NF-κB and DNMT activities, whereas zinc supplementation reduce NF-κB and DNMT activities-induced 2100 MHz EMF.


Assuntos
Telefone Celular , Neoplasias , DNA , Campos Eletromagnéticos/efeitos adversos , Fibroblastos , Humanos , Metiltransferases , NF-kappa B , Zinco
17.
Bioelectromagnetics ; 43(3): 182-192, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35094404

RESUMO

Workers inside transmission pylons with FM antenna arrays are likely to be exposed to near-field radiation exceeding reference levels for occupational exposure. In this study, the near-field behavior of 64 FM pylons was studied using a new methodology. Near-field characterization was done using field metrics without taking into account field sources' size or distance from field source. The specific absorption rate (SAR) was assessed in five hundred different near-field cases using a human phantom. Estimation formulas for both local and whole-body SAR are provided and validated numerically. Local and whole-body SAR are linked to electric field strength. © 2022 Bioelectromagnetics Society.


Assuntos
Campos Eletromagnéticos , Exposição Ocupacional , Campos Eletromagnéticos/efeitos adversos , Humanos , Exposição Ocupacional/efeitos adversos , Imagens de Fantasmas , Doses de Radiação
18.
Bioelectromagnetics ; 43(1): 47-63, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34859455

RESUMO

The work began in 1972 when three young assistant professors used a slime mold to see if electromagnetic fields would affect it. The fields did, though the effects were small and hard to tease out of the noise. The cell cycle was lengthened and there were changes in respiration. So, the next question was "how and why?" Further changes were seen using these and then other bacterial and eukaryotic cells in respiration, in ATP, in the protein replication chain, and so forth. Changes occurred even in cell extracts that lacked an intact plasma membrane. Nerve cells showed changes in leakage of neurotransmitters and in neurite outgrowth from excised ganglia. Based on some experiments with nerve cells, I also did some computer calculations, modeling the internal electric and magnetic fields and current densities in simplified representations of bone fractures and also of spinal cords in vertebrae. More recently, I have collaborated on some theoretical models of what fields might be doing at the cellular and molecular level, particularly with reference to the radical model. With each piece of research, my collaborators and I generally found a small piece of information about fields and biological systems; and each answer raised another set of questions, which is the way of science. Though bioelectromagnetic scientists have learned much and can say much at greater depth about what happens when an organism is exposed to a field, the fundamental question still remains: What exactly is going on here? © 2021 Bioelectromagnetics Society.


Assuntos
Campos Eletromagnéticos , Campos Magnéticos , Animais , Membrana Celular , Eletricidade , Campos Eletromagnéticos/efeitos adversos , Campos Magnéticos/efeitos adversos , Modelos Teóricos , Neurônios
19.
J Chem Neuroanat ; 119: 102043, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34808256

RESUMO

The purpose of this study was to highlight the possible effects on the hippocampus of the electromagnetic field (EMF) emitted by mobile phones, and to investigate whether these potential effects can be reduced using various antioxidant substances. Twenty-seven female Wistar albino rats were divided into nine equal groups, each containing three pregnant rats aged 8-10 weeks and weighing 200-250 gr. The EMF groups were exposed to 900 Megahertz (MHz) EMF for 1 h (hr) a day for 21 days. No EMF exposure was applied to the Cont and also the groups given only Garcinia kola (GK), Momordica charantia (MC), and thymoquinone (TQ). The Sham group was kept in the polycarbonate EMF exposure system, but was not exposed to EMF. Four weeks after birth, rat pups were subjected to behavioural tests. Brain tissue samples were evaluated using histological, stereological, functional, and immunohistochemical methods. The numbers of pyramidal neurons in the rat cornu ammonis (CA) were determined using the optical fractionator method. Superoxide dismutase (SOD) and catalase (CAT) enzyme activities in the blood samples were also evaluated. The analysis data indicated that total pyramidal neuron numbers were decreased significantly in the CA of the EMF (1 hr) group (p < 0.01). Our results also showed that the protective effect of MC was more potent than that of the other antioxidant substances (p < 0.01). A 900 MHz EMF can cause deleterious changes in the brain. It can also be suggested that GK, MC and TQ are capable of reducing these adverse effects.


Assuntos
Telefone Celular , Campos Eletromagnéticos , Animais , Campos Eletromagnéticos/efeitos adversos , Feminino , Hipocampo/patologia , Gravidez , Células Piramidais , Ratos , Ratos Wistar
20.
Environ Sci Pollut Res Int ; 29(12): 17932-17942, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34686958

RESUMO

Electromagnetic fields (EMFs) are common in our everyday lives. They have many origins and severe effects on individuals and environments where they inflict a great deal of health and psychological harm. The current study investigated the impact of high voltage (H.V.) EMF 5.4 kV/m for 2 and 4 h per day with a frequency equal to 50 Hz alternating current (AC) on body weight (b.wt), blood indices, and certain liver enzymes of albino rats after 25 days of exposure to the electromagnetic field. This work focuses on the therapeutic action of methanol extract of Rosmarinus officinalis (R. officinalis) leaves at a dose (5 mg/kg b. wt) against harmful EMF-induced effects. The findings showed that electromagnetic field exposure induced a substantial decrease in red blood cells (RBC), haemoglobin concentration (Hb), and catalase activity (CAT). Although white blood cells (WBCs), aspartate aminotransferase (AST), alanine aminotransferase (ALT), total bilirubin, urea, creatinine, uric acid, and malondialdehyde (MDA) levels have increased significantly under EMF treatment. Treatment with R. officinalis showed attenuation in these parameters that were induced in rats exposed to H.V. These findings were followed by the histopathological analysis of the liver in the observations. Finally, we conclude that R. officinalis leaves extract offered substantial protection against H.V-induced liver damage and can be applied in drug production.


Assuntos
Campos Eletromagnéticos/efeitos adversos , Extratos Vegetais/farmacologia , Rosmarinus , Animais , Antioxidantes/metabolismo , Aspartato Aminotransferases , Fígado , Estresse Oxidativo , Ratos , Rosmarinus/química
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