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1.
Phys Rev Lett ; 124(6): 064501, 2020 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-32109117

RESUMO

The concentration patterns of DNA molecules attached to the interface between two immiscible aqueous phases forming under an electric field are studied. The pattern formation is driven by hydrodynamic interactions between the molecules originating from the electro-osmotic flow due to the Debye layer around a molecule. A nonlinear integrodifferential equation is derived describing the time evolution of the concentration field at the liquid-liquid interface. A linear stability analysis of this equation shows that a mode of given wavelength is initially stable, but destabilizes after a critical time which is inversely proportional to the wavelength. The scaling behavior of the critical time with electric field strength and viscosity found in the experiments agrees with the predictions by the theoretical model.


Assuntos
DNA/química , Modelos Químicos , Campos Eletromagnéticos , Hidrodinâmica , Pressão Osmótica , Água/química
2.
Toxicol Lett ; 323: 35-40, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-31991167

RESUMO

This article identifies adverse effects of non-ionizing non-visible radiation (hereafter called wireless radiation) reported in the premier biomedical literature. It emphasizes that most of the laboratory experiments conducted to date are not designed to identify the more severe adverse effects reflective of the real-life operating environment in which wireless radiation systems operate. Many experiments do not include pulsing and modulation of the carrier signal. The vast majority do not account for synergistic adverse effects of other toxic stimuli (such as chemical and biological) acting in concert with the wireless radiation. This article also presents evidence that the nascent 5G mobile networking technology will affect not only the skin and eyes, as commonly believed, but will have adverse systemic effects as well.


Assuntos
Campos Eletromagnéticos/efeitos adversos , Tecnologia sem Fio , Consenso , Humanos
3.
Environ Monit Assess ; 192(2): 77, 2020 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-31897614

RESUMO

Several studies have characterized personal exposure to RF-EMF, which allows possible effects on health to be studied. All equipment has a detection limit, below which we obtain nondetects or censored data. This problem is a challenge for researchers as it makes the analysis of such data complex. We suggest reconsidering the statistical protocols of the nondetects analysis by comparing four different methods. Three of them substitute censored data using different approaches: regression on order of statistics (ROS) to simulate data below the detection limit (Method 1), substituting nondetect values by the detection limit divided by 2 (Method 2), a naïve calculation (Method 3) using the detection limit as a valid measurement. The fourth method consists of considering censored data to be missing values (Method 4). This article examines how these methods affect the quantification of personal exposure. We considered data from 14 frequency bands from FM to WiMax measured in Albacete (Spain) for 76 days every 10 s by a personal exposimeter (PEM) Satimo EME Spy 140.Methods 3 and 2 gave similar mean and median values to Method 1, but both underestimated the mean values when high nondetects records occurred, which conditioned the physical description of the real situation. The mean values calculated by Method 4 differed from those obtained by Method 1 but were similar when the percentage of nondetects was below 20%.Our comparison suggests that nondetects can be neglected when the percentage of censored data is low to provide a more realistic physical situation.


Assuntos
Campos Eletromagnéticos , Exposição Ambiental/análise , Ondas de Rádio , Algoritmos , Monitoramento Ambiental , Humanos , Limite de Detecção , Análise de Regressão , Projetos de Pesquisa , Espanha
4.
J Chem Phys ; 152(3): 035104, 2020 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-31968963

RESUMO

Nonthermal effects of the electromagnetic (EM) field in the radio and microwave frequency ranges on basic biological matter are difficult to detect and thus remain poorly understood. In this work, all-atom nonequilibrium molecular dynamics simulations were performed to investigate the molecular mechanisms of an amyloidogenic peptide response to nonionizing radiation of varying field characteristics. The results showed that the EM field induced peptide conformations dependent on the field frequency and strength. At the high field strength (0.7 V/nmrms), the peptide explored a wider conformational space as the frequency increased from 1.0 to 5.0 GHz. At the intermediate strength fields (0.07-0.0385 V/nmrms), the frequencies of 1.0 and 2.5 GHz resulted in the peptide being trapped in specific conformations, with 1.0 GHz enabling both fibril-forming and fibril-inhibiting conformations, while 2.5 GHz led to formation of mostly fibril-forming conformations. In contrast, the 5.0 GHz frequency caused increased peptide dynamics and more extended conformations with fibril-enabling aromatic side-chain arrangement akin to the structures formed under ambient conditions. All the simulated frequencies at low strength fields (0.007-0.0007 V/nmrms) resulted in the formation of amyloid-prone hairpin conformations similar to those formed under the weak static electric field and ambient conditions. These results suggest that specific ranges of EM field parameters produce peptide conformations unfavorable for formation of amyloid fibrils, a phenomenon that can be exploited in treatment and prevention of amyloid diseases. Alternatively, EM field parameters can be selected to modulate the formation of well-ordered peptide assemblies as a rational design strategy for engineering biocompatible materials.


Assuntos
Proteínas Amiloidogênicas/química , Campos Eletromagnéticos , Agregados Proteicos , Agregação Patológica de Proteínas , Simulação de Dinâmica Molecular , Conformação Proteica
5.
Environ Pollut ; 256: 113461, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31706765

RESUMO

OBJECTIVE: Electrohypersensitive people attribute various symptoms to exposure of radiofrequency electromagnetic fields (RF-EMF); sleep disturbance is the most frequently cited. However, laboratory experiments have yielded conflicting results regarding sleep alterations. Our hypothesis was that exposure to RF-EMF alone would lead to slight or non-significant effects but that co-exposure to RF-EMFs and other environmental constraints (such as noise) would lead to significant effects. METHODS: 3-week-old male Wistar rats (4 groups, n = 12 per group) were exposed for 5 weeks to continuous RF-EMF (900 MHz, 1.8 V/m, SAR = 30 mW/kg) in the presence or absence of high-level noise (87.5 dB, 50-20000 Hz) during the rest period. After 5 weeks of exposure, sleep (24 h recording), food and water intakes, and body weight were recorded with or without RF-EMF and/or noise. At the end of this recording period, sleep was scored during the 1 h resttime in the absence of noise and of RF-EMF exposure. RESULTS: Exposure to RF-EMF and/or noise was associated with body weight gain, with hyperphagia in the noise-only and RF-EMF + noise groups and hypophagia in the RF-EMF-only group. Sleep parameters recording over 24 h highlighted a higher frequency of active wakefulness in the RF-EMF-only group and a lower non-rapid eye movement/rapid eye movement sleep ratio during the active period in the noise-only group. There were no differences in sleep duration in either group. During the 1-h, constraint-free sleep recording, sleep rebound was observed in the noise-only group but not in the RF-EMF-only and RF-EMF + noise groups. CONCLUSION: Our study showed effects of RF-EMF, regardless of whether or not the animals were also exposed to noise. However, the RF-EMF + noise group presented no exacerbation of those effects. Our results did not support the hypothesis whereby the effects of RF-EMF on physiological functions studied are only visible in animals exposed to both noise and RF-EMF.


Assuntos
Campos Eletromagnéticos , Ruído , Ondas de Rádio , Animais , Peso Corporal , Ingestão de Alimentos , Exposição Ambiental , Humanos , Masculino , Ratos , Ratos Wistar , Sono/fisiologia
6.
Adv Exp Med Biol ; 1237: 135-149, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31376139

RESUMO

Recently, there has been attention and controversial debate topic about the effect of low-frequency electromagnetic fields (EMFs) on human beings. The catalyst for public awareness initiated from the first epidemiological study in 1979 that reported an association between residential EMFs exposure and the incidence of childhood leukemia. For over 40 years, many epidemiological and laboratory investigations were conducted to identify the possible biological effects of low-frequency EMF. Several studies conducted at frequencies 50/60 Hz, which related to generating of electricity from electrical appliances. Experimental studies on low-frequency EMF have provided conflicting data under specific "in vivo" and "in vitro" environments. Some original papers have reported the damaging effect on DNA molecule in EMF-exposed cells. Other studies have suggested no such damage in EMF-exposed cells. Also, the conclusions from other studies were inconclusive. These conflicting findings may attribute to the differences in the apparatus used to generate electromagnetic fields, experimental design, exposure time, genetic endpoints, and biological materials such as cell lines and animal species, strain, and age. As DNA damage is frequently a prerequisite for cancer disease, this review provided an experimental body of evidence on the effect of EMF on genetic material.


Assuntos
Campos Eletromagnéticos/efeitos adversos , Dano ao DNA , Humanos , Neoplasias/genética , Reprodutibilidade dos Testes
7.
Urology ; 136: 266-271, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31734350

RESUMO

OBJECTIVE: To determine feasibility of an electromagnetic (EM) guidance system (Auris Health, Redwood City, CA) in obtaining percutaneous renal access among urologists and trainees of different experience levels. EM-guidance is appealing for access as it allows real time, 3-dimensional targeting without radiation. Few studies have explored this for percutaneous nephrolithotomy (PCNL) and none have assessed its potential to decrease the learning curve in obtaining access using traditional techniques. METHODS: Institutional Animal Care and Use Committee approval was obtained to compare EM-guided percutaneous access to fluoroscopic guided access in a porcine model. Voluntary participants included urology trainees and faculty. They were categorized as beginner (no prior primary percutaneous nephrolithotomyexperience), intermediate (10-100 prior) and advanced (>100). Each participant attempted an EM and fluoroscopic guided puncture. Primary outcome was successful puncture. Secondary outcomes included access time, fluoroscopy time, and number of attempts. Participants were limited to 3 attempts and 10 minutes total to obtain access using each technique. RESULTS: Fourteen participants (6 beginners, 4 intermediates, and 4 experts) attempted 28 punctures. Overall success using EM-guidance was 93% compared to 71% using fluoroscopy (P = .33). EM punctures had shorter access times (85 vs 255 seconds, P <.01) required fewer attempts (1 vs 2, P = .04) and had decreased associated fluoroscopy times (1 vs 96 seconds, P <.01) excluding the initial retrograde pyelogram and guidance of the ureteroscope to the desired calyx. Beginners showed comparable success rates and outcomes relative to experts despite higher access times. CONCLUSION: EM-guidance is a promising new technique to decrease the learning curve of percutaneous access with high success rates and minimal radiation.


Assuntos
Competência Clínica , Campos Eletromagnéticos , Nefrolitotomia Percutânea/métodos , Urologia , Animais , Estudos de Viabilidade , Projetos Piloto , Suínos
8.
Bioelectromagnetics ; 41(1): 21-33, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31755122

RESUMO

The present study is part of an ongoing effort to develop a simple diagnostic technology for detecting internal bleeding in the brain, which can be used in lieu or in support of medical imaging and thereby reduce the cost of diagnostics in general, and in particular, would make diagnostics accessible to economically disadvantaged populations. The study deals with a single coil inductive device to be used for detecting cerebral hemorrhage. It presents a first-order experimental study that examines the predictions of our recently published theoretical study. The experimental model employs a homogeneous cylindrical phantom in which internal head bleeding was simulated by way of a fluid inclusion. We measured the changes in amplitude and phase across the coil with a network vector analyzer as a function of frequency (100-1,000 MHz), volume of blood simulating fluid, and the site of the fluid injection. We have developed a new mathematical model to statistically analyze the complex data produced in this experiment. We determined that the resolution for the fluid volume increase following fluid injection is strongly dependent on frequency as well as the location of liquid accumulation. The experimental data obtained in this study supports the predictions of our previous theoretical study, and the statistical analysis shows that the simple single coil device is sensitive enough to detect changes due to fluid volume alteration of two milliliters. Bioelectromagnetics. 2020;41:21-33 © 2019 Bioelectromagnetics Society.


Assuntos
Determinação do Volume Sanguíneo/métodos , Simulação por Computador , Imagens de Fantasmas , Acidente Vascular Cerebral/diagnóstico , Volume Sanguíneo , Condutividade Elétrica , Campos Eletromagnéticos , Desenho de Equipamento , Transdutores
9.
Bioelectromagnetics ; 41(1): 73-79, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31746011

RESUMO

Human exposure to electromagnetic fields produced by two wearable antennas operating in the 2.4 GHz frequency band was assessed by computational tools. Both antennas were designed to be attached to the skin, but they were intended for different applications. The first antenna was designed for off-body applications, i.e. to communicate with a device placed outside the body, while the second antenna model was optimized to communicate with a device located inside the body. The power absorption in human tissues was determined at several locations of adult male and female body models. The maximum specific absorption rate (SAR) value obtained with the off-body antenna was found on the torso of the woman model and was equal to 0.037 W/kg at 2.45 GHz. SAR levels increased significantly for the antenna transmitting inside the body. In this case, SAR values ranged between 0.23 and 0.45 W/kg at the same body location. The power absorbed in different body tissues and total power absorbed in the body were also calculated; the maximum total power absorbed was equal to 5.2 mW for an antenna input power equal to 10 mW. Bioelectromagnetics. 2020;41:73-79 © 2019 Wiley Periodicals, Inc.


Assuntos
Campos Eletromagnéticos/efeitos adversos , Desenho de Equipamento/instrumentação , Dispositivos Eletrônicos Vestíveis , Absorção de Radiação , Simulação por Computador , Radiação Eletromagnética , Feminino , Humanos , Masculino , Modelos Biológicos , Próteses e Implantes , Pele/metabolismo
10.
Food Chem ; 304: 125442, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-31491714

RESUMO

In this study, the effects of moderate electric fields during thermal denaturation of ß-lactoglobulin were examined through an in situ circular dichroism approach, complemented by intrinsic extrinsic fluorescence analysis. Results have shown that the effects of electric fields in protein unfolding were linearly dependent on the applied electric field intensity (V/cm) and increased by the use of low electric frequencies - i.e. 50 to 200 Hz. These electric effects caused significant changes on ß-lactoglobulin melting temperature, unfolded conformation and subsequent intermolecular interactions, revealed by the increase of surface hydrophobicity (ANS affinity) and higher conservation of retinol binding. The obtained data provides a clear evidence that moderate electric fields contribute to distinct folding/unfolding of ß-lactoglobulin, resulting in structural modifications. These findings are relevant for (bio)-technological applications involving electric fields processing, bringing new insights for the development of innovative strategies to control protein function and tune production of functional protein systems.


Assuntos
Campos Eletromagnéticos , Lactoglobulinas/química , Desdobramento de Proteína , Temperatura Ambiente , Dicroísmo Circular , Interações Hidrofóbicas e Hidrofílicas , Lactoglobulinas/metabolismo , Conformação Proteica
11.
Bioelectromagnetics ; 41(1): 3-20, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31854006

RESUMO

Wireless wearable and implantable devices are continuing to grow in popularity, and as this growth occurs, so too does the need to consider the safety of such devices. Wearable and implantable devices require the transmitting and receiving of electromagnetic waves near and through the body, which at high enough exposure levels may damage proximate tissues. The specific absorption rate (SAR) is the quantity commonly used to enumerate exposure levels, and various national and international organizations have defined regulations limiting exposure to ensure safe operation. In this paper, we comprehensively review dosimetric studies reported in the literature up to the year 2019 for wearables and implants. We discuss antenna designs for wearables and implants as they relate to SAR values and field and thermal distributions in tissue, present designs that have made steps to reduce SAR, and then review SAR considerations as they relate to applied devices. As compared with previous review papers, this paper is the first review to focus on dosimetry aspects relative to wearable and implantable devices. Bioelectromagnetics. 2020;41:3-20 © 2019 The Authors. Bioelectromagnetics published by Wiley Periodicals, Inc.


Assuntos
Radiometria/instrumentação , Tecnologia sem Fio/instrumentação , Campos Eletromagnéticos , Humanos , Músculo Esquelético/efeitos da radiação , Próteses e Implantes , Exposição à Radiação/análise , Temperatura Ambiente , Dispositivos Eletrônicos Vestíveis
12.
J Orthop Res ; 38(1): 160-172, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31769535

RESUMO

Strategies aiming at controlling and modulating inflammatory cues may offer therapeutic solutions for improving tendon regeneration. This study aims to investigate the modulatory effect of pulsed electromagnetic field (PEMF) on the inflammatory profile of human tendon-derived cells (hTDCs) after supplementation with interleukin-1ß (IL-1ß). IL-1ß was used to artificially induce inflammatory cues associated with injured tendon environments. The PEMF effect was investigated varying the frequency (5 or 17 Hz), intensity (1.5, 4, or 5 mT), and duty-cycle (10% or 50%) parameters to which IL-1ß-treated hTDCs were exposed to. A PEMF actuation with 4 mT, 5 Hz and a 50% duty cycle decreased the production of IL-6 and tumor necrosis factor-α (TNF-α), as well as the expression of TNFα, IL-6, IL-8, COX-2, MMP-1, MMP-2, and MMP-3, while IL-4, IL-10, and TIMP-1 expression increased. These results suggest that PEMF stimulation can modulate hTDCs response in an inflammatory environment holding therapeutic potential for tendon regenerative strategies. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 38:160-172, 2020.


Assuntos
Campos Eletromagnéticos , Interleucina-1beta/farmacologia , Tendões/citologia , Adulto , Comunicação Celular/efeitos dos fármacos , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Humanos , Interleucina-6/metabolismo , Sistema de Sinalização das MAP Quinases , Tendões/imunologia , Fator de Necrose Tumoral alfa/metabolismo
13.
Ecotoxicol Environ Saf ; 188: 109786, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-31698176

RESUMO

In the last few decades, tremendous increase in the use of wireless electronic gadgets, particularly the cell phones, has significantly enhanced the levels of electromagnetic field radiations (EMF-r) in the environment. Therefore, it is pertinent to study the effect of these radiations on biological systems including plants. We investigated comparative cytotoxic and DNA damaging effects of 900 and 1800 MHz EMF-r in Allium cepa (onion) root meristematic cells in terms of mitotic index (MI), chromosomal aberrations (CAs) and single cell gel electrophoresis (comet assay). Onion bulbs were subjected to 900 and 1800 MHz (at power densities 261 ±â€¯8.50 mW m-2 and 332 ±â€¯10.36 mW m-2, respectively) of EMF-r for 0.5 h, 1 h, 2 h, and 4 h. Root length declined by 13.2% and 12.3%, whereas root thickness was increased by 46.7% and 48.3% after 4 h exposure to 900 MHz and 1800 MHz, respectively. Cytogenetic studies exhibited clastogenic effect of EMF-r as depicted by increased CAs and MI. MI increased by 36% and 53% after 2 and 4 h exposure to 900 MHz EMF-r, whereas it increased by 41% and 67% in response to 1800 MHz EMF-r. Aberration index was increased by 41%-266% and 14%-257% during 0.5-4 h of exposure to 900 MHz and 1800 MHz, respectively, over the control. EMF-r exposure decreased % head DNA (DNAH) and increased % tail DNA (DNAT) and olive tail moment (OTM) at both 900 and 1800 EMF-r. In 4 h exposure treatments, head DNA (%) declined by 19% and 23% at 900 MHz and 1800 MHz, respectively. DNAT and OTM were increased by 2.3 and 3.7 fold upon exposure to 900 MHz EMF-r over that in the control, whereas 2.8 and 5.8 fold increase was observed in response to 1800 MHz EMF-r exposure for 4 h and the difference was statistically significant. The study concludes that EMF-r in the communication range (900 and 1800 MHz) adversely affect root meristems in plants and induce cytotoxic and DNA damage. EMF-r induced DNA damage was more pronounced at 1800 MHz than that at 900 MHz.


Assuntos
Aberrações Cromossômicas/efeitos da radiação , Dano ao DNA , Campos Eletromagnéticos/efeitos adversos , Radiação Eletromagnética , Meristema/efeitos da radiação , Cebolas/efeitos da radiação , Telefone Celular , Ensaio Cometa , Relação Dose-Resposta à Radiação , Meristema/citologia , Meristema/genética , Índice Mitótico , Cebolas/citologia , Cebolas/genética , Fatores de Tempo
14.
Phys Rev Lett ; 123(23): 238101, 2019 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-31868441

RESUMO

Ultrasound irradiation makes it possible to generate alternating electric polarization through the electromechanical coupling of materials. It follows that electromagnetic fields are often emitted to the surrounding environment when materials are acoustically stimulated. We investigate the acoustically stimulated electromagnetic (ASEM) response of soft biological tissues. The ASEM signal is detected through a capacitive resonant antenna tuned to the MHz frequency of the irradiated ultrasound waves. The signal is well explained by the stress-induced polarization, which responds linearly to the applied acoustic stress. Induced polarization is clearly observed in the Achilles tendon, aortic wall, and aortic valve samples, whereas it is small in adipose tissue and myocardium samples, indicating that fibrous tissues exhibit electromechanical coupling.


Assuntos
Tendão do Calcâneo/efeitos da radiação , Tecido Adiposo/efeitos da radiação , Aorta/efeitos da radiação , Coração/efeitos da radiação , Ondas Ultrassônicas , Animais , Valva Aórtica/efeitos da radiação , Bovinos , Polaridade Celular/efeitos da radiação , Campos Eletromagnéticos , Modelos Biológicos , Suínos
15.
Spine (Phila Pa 1976) ; 44(22): E1290-E1297, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31689248

RESUMO

STUDY DESIGN: This is an in vitro study of bovine disc cells exposed to pulsed electromagnetic fields. OBJECTIVE: The purpose of the present study was to investigate whether pulsed electromagnetic fields (PEMF) effects on the expression of interleukin-6 (IL-6) expression is mediated by two known inflammation regulators, nuclear factor-κB (NF-κß) and phosphorylated mitogen-activated protein kinase p38 (p38-MAPK) signaling pathways SUMMARY OF BACKGROUND DATA.: Inflammatory cytokines play a dominant role in the pathogenesis of disc degeneration. Increasing evidence showed that PEMF, a noninvasive biophysical stimulation, can have physiologically beneficial effects on inflammation and tissue repair. Our previous research shows that PEMF treatment can reduce IL-6 expression by intervertebral disc cells. However, the underlying mechanisms of PEMF action are yet to be uncovered. METHODS: Intervertebral disc nuclear pulposus cells were challenged with interleukin-1α (IL-1α) (for mimicking inflammatory microenvironment) and treated with PEMF simultaneously up to 4 hours. Cells were then collected for NF-κß and phosphorylated p38-MAPK protein detection with Western blot. Additionally, the RelA (p65) subunit of NF-κß was examined with immunostaining for assessment of NF-κß activation. RESULTS: As expected, Western blot results showed that both NF-κß and phosphorylated p38 expression were significantly increased by IL-1α treatment. This induction was significantly inhibited to control condition levels by PEMF treatment. Immunostaining demonstrated similar trends, that PEMF treatment reduced the NF-κß activation induced by IL-1α exposure. CONCLUSION: Our data indicate that the previously-reported inhibitory effect of PEMF treatment on disc inflammation is mediated by NF-κß and phosphorylated p38-MAPK signaling pathways. These results further establish PEMFs anti-inflammatory activity, and may inform potential future clinical uses for management of inflammation associated with disc degeneration. LEVEL OF EVIDENCE: N/A.


Assuntos
Campos Eletromagnéticos , Interleucina-6/metabolismo , Disco Intervertebral , NF-kappa B/metabolismo , Transdução de Sinais/efeitos da radiação , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Animais , Bovinos , Disco Intervertebral/citologia , Disco Intervertebral/metabolismo , Disco Intervertebral/efeitos da radiação
16.
J Drugs Dermatol ; 18(11): 1088, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31738491

RESUMO

Electromagnetic field devices, specifically high intensity focused electro-magnetic field (HIFEM), comprise the latest class of technologies being developed for dermatologic applications. The FDA clearance of these technologies includes such intended uses as "the stimulation of neuromuscular tissue for bulk muscle excitation in the legs or arms" and improvement of abdominal tone, strengthening of the abdominal muscles, development of firmer abdomen; strengthening, toning and firming of buttocks, thighs and calves; and improve FFcment of muscle tone and firmness, for strengthening muscles in arms."1,2


Assuntos
Campos Eletromagnéticos , Terapia de Campo Magnético/instrumentação , Dermatopatias/radioterapia , Técnicas Cosméticas , Dermatologia , Humanos
17.
Folia Histochem Cytobiol ; 57(4): 159-167, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31746453

RESUMO

INTRODUCTION: The extremely-low frequency electromagnetic field (ELFEMF) has been proposed for use in cancer therapy since it was found that magnetic waves interfere with many biological processes. Gold nanoparticles (Au-NPs) have been widely used for drug delivery during cancer in vitro studies due to their low cytotoxity and high biocompatibility. The electroporation of cancer cells in a presence of Au-NPs (EP Au-NPs) can induce cell apoptosis, alterations of cell cycle profile and morphological changes. The impact of ELFEMF and EP Au-NPs on morphology, cell cycle and activation of apoptosis-associated genes on Hep-2 laryngeal cancer cell line has not been studied yet. MATERIALS AND METHODS: ELFEMF on Hep-2 cells were carried out using four different conditions: 25/50 mT at 15/30 min, while Au-NPs were used as direct contact (DC) or with electroporation (EP, 10 pulses at 200V, equal time intervals of 4 sec). MTT assay was used to check the toxicity of DC Au-NPs. Expression of CASP3, P53, BAX and BCL2 genes was quantified using qPCR. Cell cycle was analyzed by flow cytometry. Hematoxylin and eosin (HE) staining was used to observe cell morphology. RESULTS: Calculated IC50 of DC Au-NPs 24.36 µM (4.79 µg/ml) and such concentration was used for further DC and EP AuNPs experiments. The up-regulation of pro-apoptotic genes (CASP3, P53, BAX) and decreased expression of BCL2, respectively, was observed for all analyzed conditions with the highest differences for EP AuNPs and ELFEMF 50 mT/30 min in comparison to control cells. The highest content of cells arrested in G2/M phase was observed in ELFEMF-treated cells for 30 min both at 25 or 50 mT, while the cells treated with EP AuNPs or ELFEMF 50 mT/15 min showed highest ratios of apoptotic cells. HE staining of electroporated cells and cells exposed to ELFEMF's low and higher frequencies for different times showed nuclear pleomorphic cells. Numerous apoptotic bodies were observed in the irregular cell membrane of neoplastic and necrotic cells with mixed euchromatin and heterochromatin. CONCLUSIONS: Our observations indicate that treatment of Hep-2 laryngeal cancer cells with ELFEMF for 30 min at 25-50 mT and EP Au-NPs can cause cell damage inducing apoptosis and cell cycle arrest.


Assuntos
Antineoplásicos/farmacologia , Ouro/química , Nanopartículas Metálicas/química , Antineoplásicos/química , Antineoplásicos/toxicidade , Apoptose/efeitos dos fármacos , Proteínas Reguladoras de Apoptose/genética , Proteínas Reguladoras de Apoptose/metabolismo , Linhagem Celular Tumoral , Regulação para Baixo , Campos Eletromagnéticos , Eletroporação/métodos , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Ouro/toxicidade , Humanos , Nanopartículas Metálicas/toxicidade , Regulação para Cima
18.
Bioelectromagnetics ; 40(8): 588-601, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31663626

RESUMO

Owing to the development of information technology and the electronics industry, and the increase in the use of electronic products, an increasing number of people are exposed to electromagnetic fields (EMFs) in daily life. There has been concern about the effects of EMFs on the human body. Th9 cells, which are characterized by the generation of interleukin-(IL-9), are a recently defined subset of T helper (Th) cells. In this study, we investigated the effect of extremely low-frequency (60 Hz) EMFs, such as those generated by household power sources, at 0.8 mT intensity on CD4+ T cells. The exposure of CD4+ T cells to such EMFs under Th9-polarizing conditions increased IL-9 secretion and gene expression of transcription factors that are important for Th9 development. The expression of GATA3 increased in the early stage, and the phosphorylation of STAT5 and STAT6, which regulate the expression of GATA3, increased. In addition, EMFs increased the expression of IL-2 by the T cells. In conclusion, the differentiation of CD4+ T cells to the Th9 phenotype was increased by exposure to extremely low-frequency EMFs, and this appeared to be dependent on the IL-2 signaling pathway. Furthermore, co-cultures of EMF-exposed Th9 cells and mast cells showed an increased expression of mast cell proteases, FcεR1α, and mast cell-derived inflammatory cytokines compared with co-cultures of non-EMF-exposed Th9 cells and mast cells. Our results suggest that EMFs enhance the differentiation of CD4+ T cells to the Th9 phenotype, resulting in mast cell activation and inflammation. Bioelectromagnetics. 2019;40:588-601. © 2019 Bioelectromagnetics Society.


Assuntos
Diferenciação Celular , Campos Eletromagnéticos , Interleucina-2/metabolismo , Linfócitos T Auxiliares-Indutores/citologia , Linfócitos T Auxiliares-Indutores/metabolismo , Animais , Linhagem Celular , Humanos , Masculino , Camundongos Endogâmicos C57BL , Transdução de Sinais
19.
Bioelectromagnetics ; 40(8): 578-587, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31642089

RESUMO

A sub-acute electromagnetic field (EMF) biological effect study was carried out on rats exposed in the Transverse ElectroMagnetic exposure chamber at 171 MHz Continuous Wave (CW). The experiments involved three exposure levels (15, 25, and 35 V/m) for 15 days with triplicate parallel sham-exposed controls in each series. All exposure conditions were simulated for the evaluation of the electromagnetic energy distribution and specific absorption rate (SAR) in the rat phantoms. Studies have shown a biphasic biological response depending on time and absorbed electromagnetic energy. Under low SAR, approximately 0.006 W/kg, EMF exposure leads to the stimulation of adrenal gland activity. This process is accompanied by an initial increase of daily excretion of corticosterone and Na+ , which is seen as a higher Na+ /K+ ratio, followed by a decrease of these parameters over time. It is possible that EMF exposure causes a stress response in animals, which is seen as an increased adrenal activity. Bioelectromagnetics. 2019;40:578-587. © 2019 Bioelectromagnetics Society.


Assuntos
Glândulas Suprarrenais/metabolismo , Campos Eletromagnéticos/efeitos adversos , Glucocorticoides/metabolismo , Mineralocorticoides/metabolismo , Animais , Corticosterona/metabolismo , Masculino , Potássio/metabolismo , Ratos , Ratos Wistar , Sódio/metabolismo
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