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1.
Sci Rep ; 14(1): 10182, 2024 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-38702382

RESUMO

Progressive cartilage deterioration leads to chronic inflammation and loss of joint function, causing osteoarthritis (OA) and joint disease. Although symptoms vary among individuals, the disease can cause severe pain and permanent disability, and effective therapies are urgently needed. Human Adipose-Derived Stem Cells (ADSCs) may differentiate into chondrocytes and are promising for treating OA. Moreover, recent studies indicate that electromagnetic fields (EMFs) could positively affect the chondrogenic differentiation potential of ADSCs. In this work, we investigated the impact of EMFs with frequencies of 35 Hertz and 58 Hertz, referred to as extremely low frequency-EMFs (ELF-EMFs), on the chondrogenesis of ADSCs, cultured in both monolayer and 3D cell micromasses. ADSC cultures were daily stimulated for 36 min with ELF-EMFs or left unstimulated, and the progression of the differentiation process was evaluated by morphological analysis, extracellular matrix deposition, and gene expression profiling of chondrogenic markers. In both culturing conditions, stimulation with ELF-EMFs did not compromise cell viability but accelerated chondrogenesis by enhancing the secretion and deposition of extracellular matrix components at earlier time points in comparison to unstimulated cells. This study showed that, in an appropriate chondrogenic microenvironment, ELF-EMFs enhance chondrogenic differentiation and may be an important tool for supporting and accelerating the treatment of OA through autologous adipose stem cell therapy.


Assuntos
Tecido Adiposo , Diferenciação Celular , Condrogênese , Campos Eletromagnéticos , Células-Tronco Mesenquimais , Humanos , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Tecido Adiposo/citologia , Células Cultivadas , Condrócitos/citologia , Condrócitos/metabolismo , Matriz Extracelular/metabolismo , Sobrevivência Celular/efeitos da radiação
2.
Sci Rep ; 14(1): 10283, 2024 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-38704416

RESUMO

In this article, the impact of radiofrequency electromagnetic field (RF-EMF) exposure from a simulated base station for the 5G New Radio (5G NR) telecommunication on rats was studied. The base station affects all age groups of the population, thus, for the first time, the experiment was conducted on male Wistar rats of three different ages (juvenile, adult, and presenile). The base station exposure parameters were chosen according to ICNIRP recommendations for limiting the exposure to radiofrequency electromagnetic field: frequency 2.4 GHz with an average specific absorption rate of 0.0076 W/kg and 0.0059 W/kg over the whole body of experimental animals. Throughout the experiment, body weight was examined weekly, and the dynamics of body weight gain was monitored. Rectal and skin surface temperature on the right hind limb was monitored weekly. Testing in the Morris water maze was performed during the last, Week 5, of RF-EMF exposure. After euthanasia, organ weights were determined in experimental and control animals. None of the investigated parameters did show any statistically significant differences between exposed and control animals of the same age. The data obtained can be used to assess the possible consequences of chronic exposure to RF-EMF from 5G NR base stations.


Assuntos
Cognição , Campos Eletromagnéticos , Ondas de Rádio , Ratos Wistar , Animais , Masculino , Ondas de Rádio/efeitos adversos , Ratos , Campos Eletromagnéticos/efeitos adversos , Cognição/efeitos da radiação , Peso Corporal/efeitos da radiação , Aprendizagem em Labirinto/efeitos da radiação
3.
PLoS One ; 19(5): e0302936, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38713716

RESUMO

Long-term evolution (LTE) radiofrequency electromagnetic field (RF-EMF) is widely used in communication technologies. Thus, the influence of RF-EMF on biological systems is a major public concern and its physiological effects remain controversial. In our previous study, we showed that continuous exposure of various human cell types to 1.7 GHz LTE RF-EMF at a specific absorption rate (SAR) of 2 W/Kg for 72 h can induce cellular senescence. To understand the precise cellular effects of LTE RF-EMF, we elaborated the 1.7 GHz RF-EMF cell exposure system used in the previous study by replacing the RF signal generator and developing a software-based feedback system to improve the exposure power stability. This refinement of the 1.7 GHz LTE RF-EMF generator facilitated the automatic regulation of RF-EMF exposure, maintaining target power levels within a 3% range and a constant temperature even during the 72-h-exposure period. With the improved experimental setup, we examined the effect of continuous exposure to 1.7 GHz LTE RF-EMF at up to SAR of 8 W/Kg in human adipose tissue-derived stem cells (ASCs), Huh7, HeLa, and rat B103 cells. Surprisingly, the proliferation of all cell types, which displayed different growth rates, did not change significantly compared with that of the unexposed controls. Also, neither DNA damage nor cell cycle perturbation was observed in the 1.7 GHz LTE RF-EMF-exposed cells. However, when the thermal control system was turned off and the subsequent temperature increase induced by the RF-EMF was not controlled during continuous exposure to SAR of 8 W/Kg LTE RF-EMF, cellular proliferation increased by 35.2% at the maximum. These observations strongly suggest that the cellular effects attributed to 1.7 GHz LTE RF-EMF exposure are primarily due to the induced thermal changes rather than the RF-EMF exposure itself.


Assuntos
Proliferação de Células , Campos Eletromagnéticos , Ondas de Rádio , Humanos , Proliferação de Células/efeitos da radiação , Ratos , Animais , Células HeLa , Temperatura
4.
Sci Rep ; 14(1): 11060, 2024 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-38744931

RESUMO

In this paper the photobiomodulation on isolated mitochondria of bovine liver is studied as a thermodynamic process of conversion of energy. This analysis is conducted by considering a particular set-up for the photobiomodulation experiments of interest. It allows, in particular, the computation of the electromagnetic field and the related energetic quantities in the stimulated organelles. The measurements of the excess of biochemical power density produced by the illuminated mitochondria are performed at regular time intervals after the experiments. The calculations and the measurements finally allow us to obtain the first results on the efficiency of the process of conversion of electromagnetic energy into excess of biochemical energy released by the isolated organelles.


Assuntos
Mitocôndrias Hepáticas , Animais , Bovinos , Mitocôndrias Hepáticas/metabolismo , Mitocôndrias Hepáticas/efeitos da radiação , Terapia com Luz de Baixa Intensidade/métodos , Metabolismo Energético , Termodinâmica , Campos Eletromagnéticos , Mitocôndrias/metabolismo , Mitocôndrias/efeitos da radiação
5.
Med Pr ; 75(2): 133-141, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38717134

RESUMO

BACKGROUND: The study aimed to investigate the influence of extremely low-frequency electromagnetic fields (ELF-EMF) on clear cell renal cell carcinoma (ccRCC) by assessing alterations in gene expression and the secretion of cytokines and chemokines. MATERIAL AND METHODS: Three ccRCC cell lines (786-O, 769-P, and CAKI-1) and a healthy HEK293 cell line were subjected to ELF-EMF exposure (frequency 50 Hz, magnetic field strength 4.5 mT) for 30 min daily for 5 days. The study examined the expression of ADAM28, NCAM1, and VEGFC genes, along with the secretion of 30 cytokines and chemokines. RESULTS: Notably, primary tumor-derived cell lines, but not those from metastatic sites, exhibited ADAM28 gene expression, which increased following ELF-EMF exposure. A statistically significant reduction in VEGFC gene expression was observed in 769-P cells after ELF-EMF exposure. Additionally, NCAM1 gene expression was upregulated in HEK293, 769-P, and 786-O cells, representing normal embryonic kidney cells and primary tumor cells, but not in CAKI-1 cells, which model metastatic sites. After EMF exposure, there was a statistically significant decrease in transforming growth factor ß1 (TGF-ß1) concentration in the cell culture supernatants of HEK293 and CAKI-1 cell lines, with no other significant changes in the secretion of tested cytokines. CONCLUSIONS: Given the study's findings and available research, caution is warranted when drawing conclusions about the potential inhibitory effect of ELF-EMF on ccRCC progression. Standardization of experimental models is imperative when assessing the effects of EMF in a human context. Med Pr Work Health Saf. 2024;75(2):133-141.


Assuntos
Carcinoma de Células Renais , Citocinas , Campos Eletromagnéticos , Neoplasias Renais , Humanos , Citocinas/metabolismo , Neoplasias Renais/genética , Neoplasias Renais/patologia , Carcinoma de Células Renais/genética , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Expressão Gênica/efeitos da radiação
6.
Anticancer Res ; 44(6): 2407-2415, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38821617

RESUMO

BACKGROUND/AIM: Caffeic acid phenethyl ester (CAPE) exerts anticancer effects against several cancer types, including breast cancer. Pulsed electromagnetic field (PEMF) improves the efficiency of some chemotherapeutic drugs. In this study, we examined the effects of PEMF stimulation on the anticancer activity of CAPE in MCF-7 breast cancer cells and the underlying signal transduction pathways. MATERIALS AND METHODS: MCF-7 cells were seeded and incubated for 24 h. Each of the drugs (5-fluorouracil, paclitaxel, gefitinib, or CAPE) was added to the cells on day 0. Then, cells were immediately stimulated with a 60-min PEMF session thrice a day (with 4-h interval between sessions) for 1-3 days. Cell death and viability were assessed by flow cytometry and trypan blue dye exclusion assay. Molecular mechanisms involved in cell death were confirmed by western blot assay. RESULTS: Compared with treatment with CAPE alone, co-treatment with CAPE and PEMF more strongly reduced the viability of MCF-7 cells, further increased the percentage of the sub-G1 population, poly (ADP-ribose) polymerase (PARP) cleavage, activation of apoptotic caspases, up-regulation of pro-apoptotic proteins, such as Fas cell surface death receptor (FAS) and BCL2 associated X, apoptosis regulator (BAX), and reduced the expression of anti-apoptotic proteins, such as BCL-2 apoptosis regulator (BCL-2), MCL-1 apoptosis regulator, BCL-2 family member (MCL-1), and survivin. PEMF stimulation also increased CAPE-induced phosphorylation of p53, and inhibition of p53 partially restored the PEMF-reduced viability of CAPE-treated MCF-7 cells. CONCLUSION: PEMF stimulation enhanced CAPE-induced cell death by activating p53, which regulates the expression of apoptosis-related molecules, subsequently activating the caspase-dependent apoptotic pathway in MCF-7 cells, suggesting that PEMF can be utilized as an adjuvant to enhance the effect of CAPE on breast cancer cells.


Assuntos
Apoptose , Neoplasias da Mama , Ácidos Cafeicos , Campos Eletromagnéticos , Álcool Feniletílico , Humanos , Ácidos Cafeicos/farmacologia , Álcool Feniletílico/análogos & derivados , Álcool Feniletílico/farmacologia , Neoplasias da Mama/patologia , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Células MCF-7 , Feminino , Apoptose/efeitos dos fármacos , Apoptose/efeitos da radiação , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Transdução de Sinais/efeitos dos fármacos
7.
Metabolomics ; 20(3): 55, 2024 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-38762651

RESUMO

INTRODUCTION: The world is experiencing exponential growth in communication, especially wireless communication. Wireless connectivity has recently become a part of everyone's daily life. Recent developments in low-cost, low-power, and miniature devices contribute to a significant rise in radiofrequency-electromagnetic field (RF-EM) radiation exposure in our environment, raising concern over its effect on biological systems. The inconsistent and conflicting research results make it difficult to draw definite conclusions about how RF-EM radiation affects living things. OBJECTIVES: This study identified two micro-environments based on their level of exposure to cellular RF-EM radiation, one with significantly less exposure and another with very high exposure to RF-EM radiation. Emphasis is given to studying the metabolites in the urine samples of humans naturally exposed to these two different microenvironments to understand short-term metabolic dysregulations. METHODS: Untargeted 1H NMR spectroscopy was employed for metabolomics analyses to identify dysregulated metabolites. A total of 60 subjects were recruited with 5 ml urine samples each. These subjects were divided into two groups: one highly exposed to RF-EM (n = 30) and the other consisting of low-exposure populations (n = 30). RESULTS: The study found that the twenty-nine metabolites were dysregulated. Among them, 19 were downregulated, and 10 were upregulated. In particular, Glyoxylate and dicarboxylate and the TCA cycle metabolism pathway have been perturbed. The dysregulated metabolites were validated using the ROC curve analysis. CONCLUSION: Untargeted urine metabolomics was conducted to identify dysregulated metabolites linked to RF-EM radiation exposure. Preliminary findings suggest a connection between oxidative stress and gut microbiota imbalance. However, further research is needed to validate these biomarkers and understand the effects of RF-EM radiation on human health. Further research is needed with a diverse population.


Assuntos
Metaboloma , Metabolômica , Ondas de Rádio , Humanos , Masculino , Adulto , Metabolômica/métodos , Feminino , Ondas de Rádio/efeitos adversos , Metaboloma/efeitos da radiação , Pessoa de Meia-Idade , Campos Eletromagnéticos/efeitos adversos , Adulto Jovem
8.
J Magn Reson ; 362: 107690, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38692250

RESUMO

This research report describes a novel surface dielectric resonator (SDR) with a flexible connector for in vivo electron paramagnetic resonance (EPR) spectroscopy. Contrary to the conventional cavity or surface loop-gap resonators, the newly developed SDR is constructed from a ceramic dielectric material, and it is tuned to operate at the L-band frequency band (1.15 GHz) in continuous-wave mode. The SDR is designed to be critically coupled and capable of working with both very lossy samples, such as biological tissues, and non-lossy materials. The SDR was characterized using electromagnetic field simulations, assessed for sensitivity with a B1 field-perturbation method, and validated with tissue phantoms using EPR measurements. The results showed remarkably higher sensitivity in lossy tissue phantoms than the previously reported multisegment surface-loop resonators. The new SDR can provide potential new insights for advancements in the application of in vivo EPR spectroscopy for biological measurements, including clinical oximetry.


Assuntos
Campos Eletromagnéticos , Desenho de Equipamento , Imagens de Fantasmas , Espectroscopia de Ressonância de Spin Eletrônica/métodos , Espectroscopia de Ressonância de Spin Eletrônica/instrumentação , Reprodutibilidade dos Testes , Oximetria/instrumentação , Oximetria/métodos
9.
Bull Exp Biol Med ; 176(5): 645-648, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38727954

RESUMO

Using the method of dominant lethal mutations, we assessed the frequency of the death of Drosophila melanogaster embryos under combined exposure to ionizing γ-radiation and non-ionizing pulsed magnetic field at various doses and modes of exposure. Mutagenic effect of combined exposure is antagonistic in nature. The antagonism is more pronounced when the following mode of exposure was used: exposure to non-ionizing pulsed magnetic field for 5 h followed by exposure to γ-radiation at doses of 3, 10, and 60 Gy. In case of reverse sequence of exposures, the antagonistic effect was statistically significant after exposure to γ-radiation at doses of 3 and 10 Gy, whereas at a dose of 20 Gy, a synergistic interaction was noted.


Assuntos
Drosophila melanogaster , Raios gama , Animais , Drosophila melanogaster/efeitos da radiação , Drosophila melanogaster/genética , Raios gama/efeitos adversos , Radiação Eletromagnética , Relação Dose-Resposta à Radiação , Campos Eletromagnéticos/efeitos adversos , Embrião não Mamífero/efeitos da radiação , Radiação Ionizante , Mutação/efeitos da radiação , Mutagênese/efeitos da radiação
10.
Turk J Med Sci ; 54(1): 291-300, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38812630

RESUMO

Background/aim: Congenital anomalies of the kidney and urinary tract(CAKUT) are the leading causes of childhood chronic kidney disease (CKD). The etiology of most of the cases is thought to be multifactorial. In this study, risk factors for CAKUT and the effect of mobile phone-related electromagnetic field (EMF) exposure during pregnancy were investigated. Materials and methods: Fifty-seven cases and 57 healthy controls under 2 years of age were included and their mothers were subjected to a questionnaire. Groups were compared for parents' demographics, pregestational (chronic disease, body mass index, use of the folic acid supplements) and antenatal variables (gestational disease, weight gain during pregnancy,) and exposures during pregnancy. To assess mobile phone-related radiation exposure, all participants were asked about their daily call time, the proximity of the phone when not in use, and the models of their mobile phones. The specific absorption rate (SAR) of the mobile phones and the effective SAR value (SAR × call time) as an indicator of EMF exposure were recorded. Results: Excess weight gain according to BMI during pregnancy was related to an increased risk of CAKUT (p=0.012). Folic acid use before pregnancy was protective for CAKUT (p = 0.028). The call time of mothers of the CAKUT group was significantly longer than the control (p = 0.001). An association was observed between higher effective SAR values and increased risk of CAKUT (p = 0.03). However the proximity of the mobile phone to the mother's body when not in use was not found as a risk factor. Conclusion: The etiology of CAKUT is multifactorial. Our results suggest that prolonged phone call and higher EMF exposure during pregnancy increases the risk of CAKUT in the offspring.


Assuntos
Telefone Celular , Campos Eletromagnéticos , Humanos , Feminino , Gravidez , Fatores de Risco , Campos Eletromagnéticos/efeitos adversos , Adulto , Estudos de Casos e Controles , Anormalidades Urogenitais/epidemiologia , Anormalidades Urogenitais/etiologia , Exposição Materna/efeitos adversos , Efeitos Tardios da Exposição Pré-Natal/epidemiologia , Refluxo Vesicoureteral
11.
Curr Radiopharm ; 17(1): 55-67, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38817005

RESUMO

BACKGROUND: Exposure to physical contamination during chemotherapy, including non-ionizing electromagnetic fields, raises concerns about the widespread sources of exposure to this type of radiation. Glioblastoma multiforme (GBM) is an aggressive central nervous system tumor that is hard to treat due to resistance to drugs such as temozolomide (TMZ). OBJECTIVE: Electromagnetic fields (EMF) and haloperidol (HLP) may have anticancer effects. In this study, we investigated the effects of TMZ, HLP, and EMF on GBM cell lines and analyzed the association between non-ionizing radiation and the risk of change in drug performance. METHODS: Cell viability and reactive oxygen species (ROS) generation were measured by MTT and NBT assay, respectively. Then, the expression levels of breast cancer-resistant protein (BCRP), Bax, Bcl2, Nestin, vascular endothelial growth factor (VEGF) genes, and P53, Bax, and Bcl2 Proteins were evaluated by real-time PCR and western blot. RESULTS: Co-treatment of GBM cells by HLP and TMZ enhanced apoptosis in T-98G and A172 cells by increasing the expression of P53 and Bax and decreasing Bcl-2. Interestingly, exposure of GBM cells to EMF decreased apoptosis in the TMZ+HLP group. CONCLUSION: In conclusion, EMF reduced the synergistic effect of TMZ and HLP. This hypothesis that patients who are treated for brain tumors and suffer from depression should not be exposed to EMF is proposed in the present study. There appears to be an urgent need to reconsider exposure limits for low-frequency magnetic fields, based on experimental and epidemiological research, the relationship between exposure to non-ionizing radiation and adverse human health effects.


Assuntos
Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP , Apoptose , Sobrevivência Celular , Campos Eletromagnéticos , Haloperidol , Proteínas de Neoplasias , Nestina , Temozolomida , Fator A de Crescimento do Endotélio Vascular , Humanos , Apoptose/efeitos dos fármacos , Apoptose/efeitos da radiação , Nestina/metabolismo , Temozolomida/farmacologia , Haloperidol/farmacologia , Fator A de Crescimento do Endotélio Vascular/metabolismo , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Proteínas de Neoplasias/metabolismo , Proteínas de Neoplasias/biossíntese , Glioblastoma/radioterapia , Glioblastoma/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Neoplasias Encefálicas/radioterapia , Neoplasias Encefálicas/metabolismo , Antineoplásicos Alquilantes/farmacologia , Glioma/radioterapia , Glioma/metabolismo , Glioma/patologia
12.
Int J Mol Sci ; 25(10)2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38791113

RESUMO

Since the establishment of regulations for exposure to extremely low-frequency (0-300) Hz electromagnetic fields, scientific opinion has prioritised the hypothesis that the most important parameter determining cellular behaviour has been intensity, ignoring the other exposure parameters (frequency, time, mode, waveform). This has been reflected in the methodologies of the in vitro articles published and the reviews in which they are included. A scope review was carried out, grouping a total of 79 articles that met the proposed inclusion criteria and studying the effects of the different experiments on viability, proliferation, apoptosis, oxidative stress and the cell cycle. These results have been divided and classified by frequency, intensity, exposure time and exposure mode (continuous/intermittent). The results obtained for each of the processes according to the exposure parameter used are shown graphically to highlight the importance of a good methodology in experimental development and the search for mechanisms of action that explain the experimental results, considering not only the criterion of intensity. The consequence of this is a more than necessary revision of current exposure protection regulations for the general population based on the reductionist criterion of intensity.


Assuntos
Apoptose , Campos Eletromagnéticos , Estresse Oxidativo , Humanos , Campos Eletromagnéticos/efeitos adversos , Estresse Oxidativo/efeitos da radiação , Animais , Apoptose/efeitos da radiação , Ciclo Celular/efeitos da radiação , Sobrevivência Celular/efeitos da radiação , Proliferação de Células/efeitos da radiação
13.
Int J Mol Sci ; 25(7)2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38612655

RESUMO

In this paper we would like to highlight the problems of conceiving the "Hydrogen Bond" (HB) as a real short-range, directional, electrostatic, attractive interaction and to reframe its nature through the non-approximated view of condensed matter offered by a Quantum Electro-Dynamic (QED) perspective. We focus our attention on water, as the paramount case to show the effectiveness of this 40-year-old theoretical background, which represents water as a two-fluid system (where one of the two phases is coherent). The HB turns out to be the result of the electromagnetic field gradient in the coherent phase of water, whose vacuum level is lower than in the non-coherent (gas-like) fraction. In this way, the HB can be properly considered, i.e., no longer as a "dipolar force" between molecules, but as the phenomenological effect of their collective thermodynamic tendency to occupy a lower ground state, compatible with temperature and pressure. This perspective allows to explain many "anomalous" behaviours of water and to understand why the calculated energy associated with the HB should change when considering two molecules (water-dimer), or the liquid state, or the different types of ice. The appearance of a condensed, liquid, phase at room temperature is indeed the consequence of the boson condensation as described in the context of spontaneous symmetry breaking (SSB). For a more realistic and authentic description of water, condensed matter and living systems, the transition from a still semi-classical Quantum Mechanical (QM) view in the first quantization to a Quantum Field Theory (QFT) view embedded in the second quantization is advocated.


Assuntos
Campos Eletromagnéticos , Polímeros , Ligação de Hidrogênio , Água , Hidrogênio
14.
Skin Res Technol ; 30(4): e13687, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38566505

RESUMO

BACKGROUND: The physical appearance of an individual plays a primary role as it influences the opinion of the viewer. For this reason, orthodontic therapy to improve perceived aesthetics is in high demand among patients. This factor, combined with the increase in the number of non-invasive facial aesthetic treatments, has led to the need to understand potential risk factors in the application of medical devices to the perioral skin in patients with fixed orthodontic appliances. The aim of this study was to evaluate in vitro heating of the orthodontic bracket following electromagnetic fields and negative pressure (V-EMF) used as an anti-aging treatment. METHODS: Two different types of titanium alloy wires, one made of "beta-Titanium" alloy and the other "Ni-Ti" (DW Lingual Systems GmbH-Bad Essen-Germany) were used. The orthodontic wires and brackets mounted on a resin mouth were covered with porcine muscle tissue, then subjected to anti-aging therapy with a Bi-one LifeTouchTherapy medical device (Expo Italia Srl-Florence-Italy) which generates a combination of vacuum and electromagnetic fields (V-EMF) already adopted for antiaging therapy. During administration of the therapy, the orthodontic brackets and porcine tissue were thermally monitored using a Wavetek Materman TMD90 thermal probe (Willtek Communications GmbH-Germany). In total 20 orthodontic mouths were used, 10 with Beta Titanium wires and 10 with Nickel Titanium wires. RESULTS: A temperature increase of about 1°C was recorded in each group. The outcome of the present research shows that the absolute temperatures measured on orthodontic appliances, which, despite having a slightly different curve, both show an increase in temperature of 1.1°C at the end of the session, thus falling well within the safety range of 2°C as specified by the standard CENELEC EN 45502-1. Therefore, V-EMF therapy can be considered safe for the entire dental system and for metal prostheses, which tend to heat up at most as much as biological tissue (+0.9°C/1.1°C vs. 1.1°C/1.1°C). CONCLUSION: In conclusion, anti-aging therapy with V-EMF causes a thermal increase on orthodontic brackets that is not harmful to pulp health.


Assuntos
Campos Eletromagnéticos , Níquel , Titânio , Humanos , Animais , Suínos , Vácuo , Calefação , Fios Ortodônticos , Ligas , Teste de Materiais
15.
Proc Natl Acad Sci U S A ; 121(15): e2313903121, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38557178

RESUMO

Electromagnetic radiation (EMR) in the environment, particularly in the microwave range, may constitute a public health concern. Exposure to 2.4 GHz EMR modulated by 100 Hz square pulses was recently reported to markedly increase wakefulness in mice. Here, we demonstrate that a similar wakefulness increase can be induced by the modulation frequency of 1,000 Hz, but not 10 Hz. In contrast to the carrier frequency of 2.4 GHz, 935 MHz EMR of the same power density has little impact on wakefulness irrespective of modulation frequency. Notably, the replacement of the 100 Hz square-pulsed modulation by sinusoidal-pulsed modulation of 2.4 GHz EMR still allows a marked increase of wakefulness. In contrast, continuous sinusoidal amplitude modulation of 100 Hz with the same time-averaged power output fails to trigger any detectable change of wakefulness. Therefore, alteration of sleep behavior by EMR depends upon not just carrier frequency but also frequency and mode of the modulation. These results implicate biological sensing mechanisms for specific EMR in animals.


Assuntos
Radiação Eletromagnética , Vigília , Camundongos , Animais , Campos Eletromagnéticos
16.
Biofabrication ; 16(3)2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38604162

RESUMO

Peripheral nerve injuries can lead to sensory or motor deficits that have a serious impact on a patient's mental health and quality of life. Nevertheless, it remains a major clinical challenge to develop functional nerve conduits as an alternative to autologous grafts. We applied reduced graphene oxide (rGO) as a bioactive conductive material to impart electrophysiological properties to a 3D printed scaffold and the application of a pulsed magnetic field to excite the formation of microcurrents and induce nerve regeneration.In vitrostudies showed that the nerve scaffold and the pulsed magnetic field made no effect on cell survival, increased S-100ßprotein expression, enhanced cell adhesion, and increased the expression level of nerve regeneration-related mRNAs.In vivoexperiments suggested that the protocol was effective in promoting nerve regeneration, resulting in functional recovery of sciatic nerves in rats, when they were damaged close to that of the autologous nerve graft, and increased expression of S-100ß, NF200, and GAP43. These results indicate that rGO composite nerve scaffolds combined with pulsed magnetic field stimulation have great potential for peripheral nerve rehabilitation.


Assuntos
Campos Eletromagnéticos , Grafite , Regeneração Nervosa , Impressão Tridimensional , Ratos Sprague-Dawley , Nervo Isquiático , Alicerces Teciduais , Animais , Grafite/química , Nervo Isquiático/fisiologia , Nervo Isquiático/lesões , Regeneração Nervosa/efeitos dos fármacos , Alicerces Teciduais/química , Ratos , Masculino
17.
Environ Sci Pollut Res Int ; 31(21): 31015-31027, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38619766

RESUMO

The 5G sub-6 GHz radio frequency (RF) electromagnetic fields (EMF) are the most widely used in China's communications. The public has expressed concerns about possible brain health effects of the higher frequency bands in 5G compared to 2G, 3G, and 4G bands. It is imperative to empirically investigate the potential health hazards of these novel frequency bands in 5G communication technology. This study evaluates the assessment of brain tissue dose coupling from sub-6 GHz band EMF emitted by base stations in China. Based on the 3D virtual human body model, the simulation environment was established. Dose including specific absorption rate (SAR) and internal electric field (IEF) between 2G, 3G, and 4G bands and 5G sub-6 GHz was investigated using normalized exposure values and exposure limits. The results indicate that the sub-6 GHz high-frequency band of 5G has the lowest dose value. It can be concluded that high-frequency electromagnetic radiation in 5G sub-6 GHz reduces the dose and health threats to the brain. This provides strong support for the promotion of 5G commutation in China and other regions.


Assuntos
Encéfalo , Campos Eletromagnéticos , Ondas de Rádio , China , Humanos , Encéfalo/efeitos da radiação , Radiação Eletromagnética
18.
Environ Int ; 187: 108612, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38640611

RESUMO

BACKGROUND: The technological applications of radiofrequency electromagnetic fields (RF-EMF) have been steadily increasing since the 1950s exposing large proportions of the population. The World Health Organization (WHO) is assessing the potential health effects of exposure to RF-EMF. OBJECTIVES: To systematically assess the effects of exposure to RF-EMF on self-reported non-specific symptoms in human subjects and to assess the accuracy of perceptions of presence or absence of RF-EMF exposure. METHODS: Eligibility criteria: experimental studies carried out in the general population and in individuals with idiopathic environmental intolerance attributed to EMF (IEI-EMF), in any language. INFORMATION SOURCES: Medline, Web of Science, PsycInfo, Cochrane Library, Epistemonikos, Embase and EMF portal, searched till April 2022. Risk of Bias (ROB): we used the RoB tool developed by OHAT adapted to the topic of this review. SYNTHESIS OF RESULTS: we synthesized studies using random effects meta-analysis and sensitivity analyses, where appropriate. RESULTS: Included studies: 41 studies were included, mostly cross over trials and from Europe, with a total of 2,874 participants. SYNTHESIS OF RESULTS: considering the primary outcomes, we carried out meta-analyses of 10 exposure-outcomes pairs. All evidence suggested no or small non-significant effects of exposure on symptoms with high (three comparisons), moderate (four comparisons), low (one comparison) and very low (two comparisons) certainty of evidence. The effects (standard mean difference, where positive values indicate presence of symptom being exposed) in the general population for head exposure were (95% confidence intervals) 0.08 (-0.07 to 0.22) for headache, -0.01 (-0.22 to 0.20) for sleeping disturbances and 0.13 (-0.51 to 0.76) for composite symptoms; and for whole-body exposure: 0.09 (-0.35 to 0.54), 0.00 (-0.15 to 0.15) for sleeping disturbances and -0.05 (-0.17 to 0.07) for composite symptoms. For IEI-EMF individuals SMD ranged from -0.19 to 0.11, all of them with confidence intervals crossing the value of zero. Further, the available evidence suggested that study volunteers could not perceive the EMF exposure status better than what is expected by chance and that IEI-EMF individuals could not determine EMF conditions better than the general population. DISCUSSION: Limitations of evidence: experimental conditions are substantially different from real-life situations in the duration, frequency, distance and position of the exposure. Most studies were conducted in young, healthy volunteers, who might be more resilient to RF-EMF than the general population. The outcomes of interest in this systematic review were symptoms, which are self-reported. The available information did not allow to assess the potential effects of exposures beyond acute exposure and in elderly or in chronically ill people. It cannot be ruled out that a real EMF effect in IEI-EMF groups is masked by a mix with insensitive subjects. However, studies on symptoms reporting and/or field perceptions did not find any evidence that there were particularly vulnerable individuals in the IEI-EMF group, although in open provocation studies, when volunteers were informed about the presence or absence of EMF exposure, such differences were consistently observed. INTERPRETATION: available evidence suggests that acute RF-EMF below regulatory limits does not cause symptoms and corresponding claims in the everyday life are related to perceived and not to real EMF exposure status.


Assuntos
Campos Eletromagnéticos , Exposição Ambiental , Ondas de Rádio , Autorrelato , Humanos , Campos Eletromagnéticos/efeitos adversos , Ondas de Rádio/efeitos adversos
19.
Int J Mol Sci ; 25(7)2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38612847

RESUMO

Even though electromagnetic fields have been reported to assist endogenous neurogenesis, little is known about the exact mechanisms of their action. In this pilot study, we investigated the effects of pulsating extremely low-frequency electromagnetic fields on neural stem cell differentiation towards specific phenotypes, such as neurons and astrocytes. Neural stem cells isolated from the telencephalic wall of B6(Cg)-Tyrc-2J/J mouse embryos (E14.5) were randomly divided into three experimental groups and three controls. Electromagnetic field application setup included a solenoid placed within an incubator. Each of the experimental groups was exposed to 50Hz ELF-EMFs of varied strengths for 1 h. The expression of each marker (NES, GFAP, ß-3 tubulin) was then assessed by immunocytochemistry. The application of high-strength ELF-EMF significantly increased and low-strength ELF-EMF decreased the expression of GFAP. A similar pattern was observed for ß-3 tubulin, with high-strength ELF-EMFs significantly increasing the immunoreactivity of ß-3 tubulin and medium- and low-strength ELF-EMFs decreasing it. Changes in NES expression were observed for medium-strength ELF-EMFs, with a demonstrated significant upregulation. This suggests that, even though ELF-EMFs appear to inhibit or promote the differentiation of neural stem cells into neurons or astrocytes, this effect highly depends on the strength and frequency of the fields as well as the duration of their application. While numerous studies have demonstrated the capacity of EMFs to guide the differentiation of NSCs into neuron-like cells or ß-3 tubulin+ neurons, this is the first study to suggest that ELF-EMFs may also steer NSC differentiation towards astrocyte-like phenotypes.


Assuntos
Astrócitos , Células-Tronco Neurais , Animais , Camundongos , Campos Eletromagnéticos , Projetos Piloto , Tubulina (Proteína) , Diferenciação Celular , Fenótipo
20.
Environ Int ; 185: 108552, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38458118

RESUMO

BACKGROUND: Each new generation of mobile phone technology has triggered discussions about potential carcinogenicity from exposure to radiofrequency electromagnetic fields (RF-EMF). Available evidence has been insufficient to conclude about long-term and heavy mobile phone use, limited by differential recall and selection bias, or crude exposure assessment. The Cohort Study on Mobile Phones and Health (COSMOS) was specifically designed to overcome these shortcomings. METHODS: We recruited participants in Denmark, Finland, the Netherlands, Sweden, and the UK 2007-2012. The baseline questionnaire assessed lifetime history of mobile phone use. Participants were followed through population-based cancer registers to identify glioma, meningioma, and acoustic neuroma cases during follow-up. Non-differential exposure misclassification was reduced by adjusting estimates of mobile phone call-time through regression calibration methods based on self-reported data and objective operator-recorded information at baseline. Hazard ratios (HR) and 95% confidence intervals (CI) for glioma, meningioma, and acoustic neuroma in relation to lifetime history of mobile phone use were estimated with Cox regression models with attained age as the underlying time-scale, adjusted for country, sex, educational level, and marital status. RESULTS: 264,574 participants accrued 1,836,479 person-years. During a median follow-up of 7.12 years, 149 glioma, 89 meningioma, and 29 incident cases of acoustic neuroma were diagnosed. The adjusted HR per 100 regression-calibrated cumulative hours of mobile phone call-time was 1.00 (95 % CI 0.98-1.02) for glioma, 1.01 (95 % CI 0.96-1.06) for meningioma, and 1.02 (95 % CI 0.99-1.06) for acoustic neuroma. For glioma, the HR for ≥ 1908 regression-calibrated cumulative hours (90th percentile cut-point) was 1.07 (95 % CI 0.62-1.86). Over 15 years of mobile phone use was not associated with an increased tumour risk; for glioma the HR was 0.97 (95 % CI 0.62-1.52). CONCLUSIONS: Our findings suggest that the cumulative amount of mobile phone use is not associated with the risk of developing glioma, meningioma, or acoustic neuroma.


Assuntos
Neoplasias Encefálicas , Uso do Telefone Celular , Telefone Celular , Glioma , Neoplasias Meníngeas , Meningioma , Neuroma Acústico , Humanos , Meningioma/epidemiologia , Meningioma/etiologia , Estudos de Coortes , Neuroma Acústico/epidemiologia , Neuroma Acústico/etiologia , Estudos Prospectivos , Neoplasias Encefálicas/epidemiologia , Neoplasias Encefálicas/etiologia , Glioma/epidemiologia , Glioma/etiologia , Campos Eletromagnéticos , Inquéritos e Questionários , Estudos de Casos e Controles
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