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INTRODUCTION: Chronic non-specific low back pain (CNSLBP) is a major worldwide condition that has severe emotional, social, and economic consequences. Management is difficult, requiring the development of new, effective, and safe approaches. OBJECTIVES: This study was conducted to examine the effects of Pulsed Electromagnetic Fields (PEMF) and retrowalking on pain, disability, spinal mobility, hamstring tightness, balance, and kinesiophobia in patients with chronic non-specific low back pain. MATERIALS AND METHODS: Participants (n = 48) with CNSLBP were randomised into four groups; Group A: Conventional group, Group B: PEMF group, Group C: retrowalking group, and Group D: PEMF and retrowalking group. The interventions were given three times per week for six weeks. The outcomes were pain, disability, hamstring tightness, balance, spinal mobility and kinesiophobia, measured at baseline and after 6 weeks. RESULTS: The result suggested a significant improvement in pain, disability, hamstring tightness, kinesiophobia and balance. However, no significant improvement in spinal mobility (flexion and extension ROM) was observed during the sixth week between-group comparison. The maximum improvement was seen in group D followed by group C and group B in comparison to group A. CONCLUSION: It can be concluded that PEMF and retrowalking when given in combination significantly decrease pain, disability, hamstring tightness, kinesiophobia and improve balance patients with chronic non-specific low back pain.

INTRODUÇÃO: A dor lombar crônica inespecífica (DLCI) é uma condição importante em todo o mundo que tem graves consequências emocionais, sociais e econômicas. O gerenciamento é difícil, exigindo o desenvolvimento de abordagens novas, eficazes e seguras. OBJETIVOS: Este estudo foi realizado para examinar os efeitos dos Campos Eletromagnéticos Pulsados (CEMP) e do retrowalking sobre a dor, a incapacidade, a mobilidade da coluna vertebral, a rigidez dos isquiotibiais, o equilíbrio e a cinesiofobia em pacientes com dor lombar crônica não específica. MATERIAIS E MÉTODOS: Os participantes (n = 48) com DLCI crônica foram divididos aleatoriamente em quatro grupos: Grupo A: Grupo convencional, Grupo B: Grupo CEMP, Grupo C: Grupo retrowalking e Grupo D: Grupo CEMP e retrowalking. As intervenções foram realizadas três vezes por semana durante seis semanas. Os resultados foram dor, incapacidade, tensão nos isquiotibiais, equilíbrio, mobilidade da coluna vertebral e cinesiofobia, medidos na linha de base e após seis semanas. RESULTADOS: O resultado sugeriu uma melhora significativa na dor, na incapacidade, na tensão dos isquiotibiais, na cinesiofobia e no equilíbrio. Entretanto, não foi observada melhora significativa na mobilidade da coluna vertebral (flexão e extensão da ADM) quando a comparação entre os grupos foi feita na sexta semana. A melhora máxima foi observada no grupo D, seguida pelo grupo C e pelo grupo B, em comparação com o grupo A. CONCLUSÃO: Pode-se concluir que a CEMP e o retrowalking, quando administrados em combinação, diminuem significativamente a dor, a incapacidade, a rigidez dos isquiotibiais, a cinesiofobia e melhoram o equilíbrio dos pacientes com dor crônica não espinhal.

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The long-term effects of environmental pollution have been of concern as several pollutants are carcinogenic, potentially inducing a variety of cancers, including childhood cancer, which is a leading cause of death around the world and, thus, is a public health issue. The present scoping review aimed to update and summarize the available literature to detect specific environmental pollutants and their association with certain types of childhood cancer. Studies published from 2013 to 2023 regarding environmental pollution and childhood cancer were retrieved from the PubMed database. A total of 174 studies were eligible for this review and were analyzed. Our search strategy brought up most of the articles that evaluated air pollution (29%) and pesticides (28%). Indoor exposure to chemicals (11%), alcohol and tobacco use during pregnancy (16%), electromagnetic fields (12%), and radon (4%) were the subjects of less research. We found a particularly high percentage of positive associations between prenatal and postnatal exposure to indoor (84%) and outdoor (79%) air pollution, as well as to pesticides (82%), and childhood cancer. Positive associations were found between leukemia and pesticides and air pollution (33% and 27%); CNS tumors and neuroblastoma and pesticides (53% and 43%); and Wilms tumor and other rare cancers were found in association with air pollution (50%). Indoor air pollution was mostly reported in studies assessing several types of cancer (26%). Further studies are needed to investigate the mechanisms underlying the potential associations between indoor/outdoor air pollution and pesticide exposure with childhood cancer risk as more preventable measures could be taken.

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Background: A heterogeneous geographic distribution of childhood acute lymphoblastic leukemia (ALL) cases has been described, possibly, related to the presence of different environmental factors. The aim of the present study was to explore the geographical distribution of childhood ALL cases in Greater Mexico City (GMC). Methods: A population-based case-control study was conducted. Children <18 years old, newly diagnosed with ALL and residents of GMC were included. Controls were patients without leukemia recruited from second-level public hospitals, frequency-matched by sex, age, and health institution with the cases. The residence address where the patients lived during the last year before diagnosis (cases) or the interview (controls) was used for geolocation. Kulldorff's spatial scan statistic was used to detect spatial clusters (SCs). Relative risks (RR), associated p-value and number of cases included for each cluster were obtained. Results: A total of 1054 cases with ALL were analyzed. Of these, 408 (38.7%) were distributed across eight SCs detected. A relative risk of 1.61 (p<0.0001) was observed for the main cluster. Similar results were noted for the remaining seven ones. Additionally, a proximity between SCs, electrical installations and petrochemical facilities was observed. Conclusions: The identification of SCs in certain regions of GMC suggest the possible role of environmental factors in the etiology of childhood ALL.

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In 2019, the Government of Mexico City implemented actions that allowed citizens to approach a free Wi-Fi hotspot, where more than 13000 points have been installed throughout the city. In this work, we present the results of the measurements of personal exposure to Radiofrequency Electromagnetic Fields carried out in Plaza de la Constitución, better known as Zócalo located in the center of Mexico City. The measurements were taken by one of the researchers while walking on a weekday morning and afternoon, in different microenvironments (on the street, on public transport: subway, at the Zócalo, and finally, at home). We also carry out spot measurements in the center of the Zócalo. Subsequently, we carried out a comparative analysis of the different microenvironments, through box plot and violin plot, and we elaborate georeferenced and interpolated maps with intensity levels through the Kriging method, using the Geographic Information System. The Kriging interpolation gives us a good visualization of the spatial distribution of RF-EMF exposure in the study area, showing the highest and lowest intensity levels. The mean values recorded at the measured points in the Zócalo were 326 µW/m2 in the 2.4- to 2.5-GHz Wi-Fi band and 2370 µW/m2 in the 5.15- to 5.85-GHz Wi-Fi band. In the case of the mean values recorded on the street, they were 119 µW/m2 in the 2.4- to 2.5-GHz frequency band and 31.8 µW/m2 in the 5.15- to 5.85-GHz frequency band, like the values recorded at home, 122 µW/m2 and 33.9 µW/m2, respectively. All values are well below the reference levels established by the International Commission on Non-Ionizing Radiation Protection.

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BACKGROUND: Patients with advanced hepatocellular carcinoma (HCC) and poor liver function lack effective systemic therapies. Low-energy electromagnetic fields (EMFs) can influence cell biological processes via non-thermal effects and may represent a new treatment option. METHODS: This single-site feasibility trial enrolled patients with advanced HCC, Child-Pugh A and B, Eastern Cooperative Oncology Group 0-2. Patients underwent 90-min amplitude-modulated EMF exposure procedures every 2-4 weeks, using the AutEMdev (Autem Therapeutics). Patients could also receive standard care. The primary endpoints were safety and the identification of hemodynamic variability patterns. Exploratory endpoints included health-related quality of life (HRQoL), overall survival (OS). and objective response rate (ORR) using RECIST v1.1. RESULTS: Sixty-six patients with advanced HCC received 539 AutEMdev procedures (median follow-up, 30 months). No serious adverse events occurred during procedures. Self-limiting grade 1 somnolence occurred in 78.7% of patients. Hemodynamic variability during EMF exposure was associated with specific amplitude-modulation frequencies. HRQoL was maintained or improved among patients remaining on treatment. Median OS was 11.3 months (95% confidence interval [CI]: 6.0, 16.6) overall (16.0 months [95% CI: 4.4, 27.6] and 12.0 months [6.4, 17.6] for combination therapy and monotherapy, respectively). ORR was 24.3% (32% and 17% for combination therapy and monotherapy, respectively). CONCLUSION: AutEMdev EMF exposure has an excellent safety profile in patients with advanced HCC. Hemodynamic alterations at personalized frequencies may represent a surrogate of anti-tumor efficacy. NCT01686412.

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OBJECTIVE: A volume coil with squared slots-end ring was developed to attain improved sensitivity for imaging of rat's brain at 7 T. MATERIAL AND METHODS: The principles of the high cavity resonator for the low-pass case and the law of Biot-Savart were used to derive a theoretical expression of [Formula: see text]. The slotted-end ring resonator showed a theoretical 2.22-fold sensitivity improvement over the standard birdcage coil with similar dimensions. Numerical studies were carried out for the electromagnetic fields and specific absorption rates for our coil and a birdcage coil loaded with a saline-filled spherical phantom and a digital brain of a rat. RESULTS: An improvement of the signal-to-noise ratio (SNR) can be observed for the slotted volume coil over the birdcage regardless of the load used in the electromagnetic simulations. The specific absorption rate simulations show a decrement for the digital brain and quite similar values with the saline solution phantom. Phantom and rat's brain images were acquired at 7 T to prove the viability of the coil design. The experimental noise figure of our coil design was four times less than the standard birdcage with similar dimensions, which showed a 44.5% increase in experimental SNR. DISCUSSION: There is remarkable agreement among the theoretical, numerical and experimental sensitivity values, which all demonstrate that the coil performance for MR imaging of small rodents can be improved using slotted end-rings.

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INTRODUCTION: The present study evaluated the effect of two protocols of Pulsed Electromagnetic Field (PEMF) therapy on bone neoformation on calvaria critical defects in rats. MATERIAL & METHODS: 96 rats were randomly divided into 3 groups: Control Group (CG; n=32); Test Group - PEMF 1 hour (TG1h; n=32) and Test Group - PEMF 3 hour (TG3h; n=32). A Critical-size Bone Defect (CSD) was surgically created in the calvaria of rats. The animals in the test groups were exposure to PEMF for 5 days a week. The animals were euthanized at 14, 21, 45 and 60 days. The specimens were processed for volume and texture (TAn) analysis, by Cone Beam Computed Tomography (CBCT) and histomorphometric analysis, RESULTS: Histomorphometric and volume analyses revealed that there was no statistically significant difference in the repair of bone defects between groups receiving PEMF therapy and CG. TAn revealed a statistically significant difference between the groups only for the entropy parameter, in which TG1h group presented a higher value compared to CG on 21 days. TG1h and TG3h did not accelerate bone repair in calvarial critical size defect and the parameters of PEMF should be considered. DISCUSSION: This study showed that PEMF application on CSD in rats does not accelerate bone repair. Although literature showed a positive association in biostimulation on bone tissue with the parameters applied, studies with other PEMF parameters are essential to verify improving this study design.

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Malaria, which infected more than 240 million people and killed around six hundred thousand only in 2021, has reclaimed territory after the SARS-CoV-2 pandemic. Together with parasite resistance and a not-yet-optimal vaccine, the need for new approaches has become critical. While earlier, limited, studies have suggested that malaria parasites are affected by electromagnetic energy, the outcomes of this affectation vary and there has not been a study that looks into the mechanism of action behind these responses. In this study, through development and implementation of custom applicators for in vitro experimentation, conditions were generated in which microwave energy (MW) killed more than 90% of the parasites, not by a thermal effect but via a MW energy-induced programmed cell death that does not seem to affect mammalian cell lines. Transmission electron microscopy points to the involvement of the haemozoin-containing food vacuole, which becomes destroyed; while several other experimental approaches demonstrate the involvement of calcium signaling pathways in the resulting effects of exposure to MW. Furthermore, parasites were protected from the effects of MW by calcium channel blockers calmodulin and phosphoinositol. The findings presented here offer a molecular insight into the elusive interactions of oscillating electromagnetic fields with P. falciparum, prove that they are not related to temperature, and present an alternative technology to combat this devastating disease.

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Introdução: O tratamento com campo eletromagnético focado de alta intensidade (HIFEM) usa ondas eletromagnéticas de baixa frequência para induzir contrações musculares, causando hipertrofia muscular e reduzindo a gordura subcutânea. Objetivo: avaliar os efeitos de um tratamento com HIFEM na celulite nos glúteos. Métodos: trinta mulheres foram recrutadas e randomizadas em 2 grupos que receberam 8 ou 12 sessões de HIFEM na região dos glúteos. A celulite foi avaliada utilizando a Cellulite Severity Scale, a Global Aesthetic Improvement Scale e um questionário de satisfação. Mudanças na composição corporal foram avaliadas com bioimpedância e medidas da circunferência do quadril. Resultados: a aparência global da região glútea das pacientes melhorou com o tratamento. Houve melhora na celulite de algumas pacientes, mas para a maioria a melhora não foi grande o suficiente para resultar em uma mudança de classificação na Cellulite Severity Scale. A satisfação foi alta e os eventos adversos foram poucos, não-graves e transitórios. Conclusão: os efeitos do tratamento com HIFEM na celulite da região glútea são sutis. Contudo, este tratamento é capaz de melhorar globalmente a aparência da região glútea, melhorando a percepção das pacientes sobre a gravidade de sua celulite

Introduction: High-intensity focused electromagnetic field treatment (HIFEM) uses low-frequency electromagnetic waves to induce supramaximal muscle contractions, causing muscle hypertrophy and reducing fat. Objective: To evaluate the effects of a HIFEM treatment for the improvement of cellulite on the buttocks. Methods: Thirty patients were divided into two groups that received eight or 12 HIFEM sessions on the buttocks for six weeks. We assessed the improvement in cellulite and the buttocks' global appearance through the Cellulite Severity Scale (CSS), the Global Aesthetic Improvement Scale (GAIS), and a satisfaction questionnaire. Changes in body composition were evaluated through bioimpedance and hip circumference measurements. Results: Patients from both groups improved the global appearance of their buttocks. Cellulite lesions of some patients improved, but for most patients, the improvement wasn't great enough to change the grade on the Cellulite Severity Scale. Patient satisfaction was high and adverse events were few, minor, and transitory. Conclusion: The effects of HIFEM on cellulite are subtle, as this treatment modality cannot address the fibrous septa that cause the depressed lesions of cellulite. Nevertheless, HIFEM procedures can improve the buttocks' global appearance, enhancing the patients' subjective perception of their cellulite.

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SUMMARY OBJECTIVE: The aim of this study was to examine the changes on the Purkinje cells in the cerebella of male rat pups born to pregnant dams that were exposed to an electromagnetic field in the prenatal period. METHODS: The first stage of the study involved 12 Sprague-Dawley rats, 6 male and 6 female, weighing between 180 and 250 g. The female rats in the experimental group were exposed to a 900-MHz electromagnetic field for 1 h at the same time every day, and no procedure was performed on the control group. Following pregnancy, six male pups from each group were divided into experimental and control groups without any procedure on the pups. After 2 months, they were sacrificed and their cerebella were removed. Histopathologically, following routine processing and fixation procedures, the cerebella were embedded in the tissue blocks. The sections taken from these blocks were stained with cresyl violet. The Purkinje cells in the cerebella were then counted on sections using the optical dissector method on an image analysis system. RESULTS: The estimation of number of the Purkinje cells in the groups revealed more cells in rats in the control group than in the experimental group. Histopathologically, Purkinje cells exhibited a normal morphological structure in the control group, while the cells in the experimental group showed damage. CONCLUSIONS: It might be asserted that the exposure of mothers to an electromagnetic field in the prenatal period may affect the development of Purkinje cells in the pup cerebella.

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O reparo de defeitos ósseos críticos representa um grande desafio clínico, dentre as terapias adjuvantes que apresentam um potencial benefício na aceleração do reparo ósseo destaca-se o CEMP, o qual por meio da sua estimulação biofísica é capaz de modular parâmetros fisiológicos de diferenciação, proliferação e mineralização das células ósseas. Sendo assim, o presente estudo teve como objetivo avaliar o efeito de dois protocolos de terapia com CEMP na neoformação óssea em defeitos críticos nas calotas de ratos. Noventa e seis ratos machos adultos foram divididos aleatoriamente em 3 grupos experimentais GC: (n= 32), GT1h: (n= 32) e GT3h: (n= 32). Os animais foram submetidos à cirurgia para a confecção de defeito crítico na calota craniana e à terapia com CEMP seguindo os seguintes parâmetros fixos: 25 ciclos de -1 mTesla a + 1 mTesla em 200 microssegundos que se repetiram à taxa de 15 Hz. O tempo de duração da exposição ao CEMP nos grupos testes foram de 1 hora (GT1h) e de 3 horas (GT3h), ambos durante 5 dias por semana. Os animais foram submetidos à eutanásia nos períodos 14, 21, 45 e 60 dias. Os espécimes foram processados para análise histológica, histomorfométrica e para análises de textura e volume, obtidas por meio de TCFC. As análises histomorfométrica e de volume revelaram que não houve diferença estaticamente significante no reparo dos defeitos ósseos entre os grupos que receberam a terapia com CEMP e o GC. A análise de textura revelou que houve diferença estatisticamente significante entre os grupos somente para o parâmetro entropia, no qual o grupo GT1h apresentou um maior valor comparado ao GC, ambos no período de 21 dias. Conclusão: não foi possível neste estudo mostrar um potencial benefício da utilização do CEMP na cicatrização óssea do DOC na calota de ratos. Dessa forma, esta região deve ser melhor explorada em estudos futuros, assim como a busca pelos parâmetros ideais relacionados ao gerador do CEMP de forma a maximizar os efeitos no reparo ósseo. (AU)

The repair of critical bone defects represents a major clinical challenge, among the adjuvant therapies that have a potential benefit in accelerating bone repair, PEMF stands out, which through its biophysical stimulation can modulate physiological parameters of differentiation, proliferation and mineralization of bone cells. Therefore, the present study aimed to evaluate the effect of two protocols of therapy with PEMF on bone neoformation on calvaria critical defects in rats. Ninety-six adult male rats were randomly divided into 3 experimental groups CG: (n=32), GT1h: (n=32) and GT3h: (n=32). The animals were submitted to surgery for the creation of a critical defect in the skull and to therapy with PEMF following the following fixed parameters: 25 cycles of -1 mTesla to + 1 mTesla in 200 microseconds that were repeated at a rate of 15 Hz. The duration of exposure to PEMF in the test groups was 1 hour (GT1h) and 3 hours (GT3h), both for 5 days a week. The animals were euthanized at 14, 21, 45 and 60 days. The specimens were processed for histological, histomorphometric and texture and volume analysis, obtained by CBCT. Histomorphometric and volume analyzes revealed that there was no statistically significant difference in the repair of bone defects between both groups receiving PEMF therapy and GC. The texture analysis revealed that there was a statistically significant difference between the groups, except for the entropy parameter, in which the GT1h group presented a higher value compared to CG, both in the period of 21 days. Conclusion: it was not possible in this study to show a potential benefit of using PEMF on bone healing of calvaria critical defects. Therefore, this region should be better explored in future studies, as well as seeking the ideal parameters related to the PEMF generator in order to maximize effects on bone repair (AU)

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Introducción: La generación de energía eléctrica constituye uno de los indicadores más importantes de desarrollo de una nación. En ese proceso se generan campos electromagnéticos de frecuencia extremadamente baja, que pudieran afectar el corazón. Objetivo: Identificar la asociación entre el riesgo cardiovascular y la exposición a los campos electromagnéticos de frecuencia extremadamente baja. Métodos: Se realizó un estudio transversal, descriptivo en el Área de Salud 27 de Noviembre, del municipio Marianao de la provincia La Habana, en el año 2018. La muestra estuvo constituida por 152 individuos. Se les determinó el riesgo cardiovascular, según las tablas predictivas de Gaziano sin laboratorio. Se realizaron mediciones de las densidades de flujo magnético en sus viviendas. Se valoró si estas, se asociaron a la intensidad de generación de electricidad de la vecina central termoeléctrica y con el riesgo cardiovascular global de los residentes. Se utilizó correlación no paramétrica de Spearman. Resultados: El 31,6 % de la población estudiada fue evaluada con el riesgo cardiovascular alto y muy alto en su conjunto. 120 individuos estuvieron expuestos en sus viviendas a densidades del flujo magnético entre 0 y 0,9 µT. Existió una correlación estadística significativa, entre la intensidad de la corriente generada por la industria y las densidades de flujo magnético en las habitaciones usadas para dormir. Conclusiones: No se observó asociación entre el riesgo cardiovascular y las densidades de flujo magnético medidas en las viviendas. La exposición a los campos electromagnéticos de frecuencia extremadamente baja no constituyó un factor de riesgo cardiovascular para la población estudiada.

Introduction: The generation of electrical energy constitutes one of the most important indicators of development of a nation. In this process, extremely low frequency electromagnetic fields are generated, which could affect the heart. Objective: To identify the association between global cardiovascular risk and exposure to extremely low frequency electromagnetic fields. Methods: A cross-sectional, descriptive study was carried out in the Health Area November 27, of the Marianao municipality of Havana province, in 2018. The sample consisted of 152 individuals. The cardiovascular risk was determined, according to the Gaziano predictive tables without laboratory. Measurements of magnetic flux densities were made in their homes. It was assessed whether these were associated with the intensity of electricity generation at the neighboring thermoelectric plant and with the overall cardiovascular risk of the residents. Spearman's non-parametric correlation was used. Results: 31,6% of the studied population was evaluated with high and very high cardiovascular risk as a whole. 120 individuals were exposed in their homes to magnetic flux densities between 0 and 0,9 µT. There was a statistically significant correlation between the intensity of the current generated by the industry and the magnetic flux densities in the rooms used to sleep. Conclusions: No association was observed between the cardiovascular risk and the magnetic flux densities measured in the dwellings. Exposure to extremely low frequency electromagnetic fields was not a cardiovascular risk factor for the population studied.

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The densification of multiple wireless communication systems that coexist nowadays, as well as the 5G new generation cellular systems advent towards the millimeter wave (mmWave) frequency range, give rise to complex context-aware scenarios with high-node density heterogeneous networks. In this work, a radiofrequency electromagnetic field (RF-EMF) exposure assessment from an empirical and modeling approach for a large, complex indoor setting with high node density and traffic is presented. For that purpose, an intensive and comprehensive in-depth RF-EMF E-field characterization study is provided in a public library study case, considering dense personal mobile communications (5G FR2 @28 GHz) and wireless 802.11ay (@60 GHz) data access services on the mmWave frequency range. By means of an enhanced in-house deterministic 3D ray launching (3D-RL) simulation tool for RF-EMF exposure assessment, different complex heterogenous scenarios of high complexity are assessed in realistic operation conditions, considering different user distributions and densities. The use of directive antennas and MIMO beamforming techniques, as well as all the corresponding features in terms of radio wave propagation, such as the body shielding effect, dispersive material properties of obstacles, the impact of the distribution of scatterers and the associated electromagnetic propagation phenomena, are considered for simulation. Discussion regarding the contribution and impact of the coexistence of multiple heterogeneous networks and services is presented, verifying compliance with the current established international regulation limits with exposure levels far below the aforementioned limits. Finally, the proposed simulation technique is validated with a complete empirical campaign of measurements, showing good agreement. In consequence, the obtained datasets and simulation estimations, along with the proposed RF-EMF simulation tool, could be a reference approach for the design, deployment and exposure assessment of the current and future wireless communication technologies on the mmWave spectrum, where massive high-node density heterogeneous networks are expected.

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In the food industry, some fungi are considered to be common spoilage microorganisms which reduce the shelf life of products. To avoid this outcome, different technologies are being developed to control their growth. Electromagnetic fields (EMF) have been used to combat bacterial growth, but there are few studies on yeasts and their possible action mechanisms. For this reason, we studied the effect of EMF between 1 to 5.9 GHz bands on the growth of Saccharomyces cerevisiae yeast and observed that all the frequencies of the band used cause the reduction of the viability of this yeast. In addition, we observed that the distance between the antenna and the sample is an important factor to consider to control the growing yeast. By using transmission electron microscopy, we found that the EMF caused a loss of continuity of the yeast cell membrane. Therefore, EMF may be used as a control method for yeast growth.

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In recent years, personal exposure to Radiofrequency Electromagnetic Fields (RF-EMF) has substantially increased, and most studies about RF-EMF with volunteers have been developed in Europe. To the best of our knowledge, this is the first study carried out in Mexico with personal exposimeters. The main objective was to measure personal exposure to RF-EMF from Wireless Fidelity or wireless Internet connection (Wi-Fi) frequency bands in Tamazunchale, San Luis Potosi, Mexico, to compare results with maximum levels permitted by international recommendations and to find if there are differences in the microenvironments subject to measurements. The study was conducted with 63 volunteers in different microenvironments: home, workplace, outside, schools, travel, and shopping. The mean minimum values registered were 146.5 µW/m2 in travel from the Wi-Fi 2G band and 116.8 µW/m2 at home from the Wi-Fi 5G band, and the maximum values registered were 499.7 µW/m2 and 264.9 µW/m2 at the workplace for the Wi-Fi 2G band and the Wi-Fi 5G band, respectively. In addition, by time period and type of day, minimum values were registered at nighttime, these values being 129.4 µW/m2 and 93.9 µW/m2, and maximum values were registered in the daytime, these values being 303.1 µW/m2 and 168.3 µW/m2 for the Wi-Fi 2G and Wi-Fi 5G bands, respectively. In no case, values exceeded limits established by the International Commission on Non-Ionizing Radiation Protection (ICNIRP). Of the study participants (n = 63), a subgroup (n = 35) answered a survey on risk perception. According to these results, the Tamazunchale (Mexico) population is worried about this situation in comparison with several European cities; however, the risk perception changes when they are informed about the results for the study.

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BACKGROUND: this study aims to estimate the rate of death by cancer as a result of Radio Base Station (RBS) radiofrequency exposure, especially for breast, cervix, lung, and esophagus cancers. METHODS: we collected information on the number of deaths by cancer, gender, age group, gross domestic product per capita, death year, and the amount of exposure over a lifetime. We investigated all cancer types and some specific types (breast, cervix, lung, and esophagus cancers). RESULTS: in capitals where RBS radiofrequency exposure was higher than 2000/antennas-year, the average mortality rate was 112/100,000 for all cancers. The adjusted analysis showed that, the higher the exposure to RBS radiofrequency, the higher cancer mortality was. The highest adjusted risk was observed for cervix cancer (rate ratio = 2.18). The spatial analysis showed that the highest RBS radiofrequency exposure was observed in a city in southern Brazil that also showed the highest mortality rate for all types of cancer and specifically for lung and breast cancer. CONCLUSION: the balance of our results indicates that exposure to radiofrequency electromagnetic fields from RBS increases the rate of death for all types of cancer.

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OBJECTIVES: The present study aims to evaluate two protocols of pulsed electromagnetic field (PEMF) on osseointegration and establish one that addresses ideal parameters for its use in dentistry, especially in the optimization of the implants osseointegration process. MATERIALS AND METHODS: Sixty male rats (Wistar) were allocated into three experimental groups: control (GC), test A (GTA, 3 h exposed), and test B (GTB, 1 h exposed). All animals received titanium implants in both tibias, and PEMF application (15 Hz, ± 1 mT, 5 days/week) occurred only in the test groups. They were euthanized at 03, 07, 21, and 45 days after PEMF therapy. Removal torque, histomorphometric measurements, three-dimensional radiographic evaluation, and in vitro biological assay analyses were performed. RESULTS: GTB showed better results compared with GTA in removal torque tests, in bone volume and bone mineral density, cell viability, total protein content, and mineralization nodules (p < 0.05). GTA showed better performance in trabecular bone thickness and cell proliferation compared with GTB (p < 0.05), especially at osseointegration early periods. In the histomorphometric analysis and number of trabeculae, there were no differences in the test groups. CONCLUSION: PEMF as a biostimulator was effective in optimizing the events in bone tissue that lead to osseointegration, especially when applied for a shorter time and in the initial periods of bone healing. CLINICAL RELEVANCE: The PEMF therapy is an effective alternative method for optimizing bone healing.

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BACKGROUND: Pulsed radiofrequency (PRF) affects animal and plant tissues; however, the mechanism has not been defined. We hypothesized that the magnetic field produced by PRF exerts its effects by the magnetic sensitivity of transitions between spin states -a spin-correlated radical-pair mechanism (SCRPM)- which, in turn, affects the rates of chemical reactions with participation of paramagnetic species. OBJECTIVES: This study aimed to evaluate the effects of PRF on redox equilibrium and inflammatory status in a standard model of muscle injury in rats. METHODS: Twenty-four animals were subjected to a single impact trauma to the left quadriceps and the groups exposed and not exposed to PRF were compared. On day 7 of the experiment, the animals were killed and the quadriceps muscles were removed for analysis. RESULTS: There was a significant increase in the concentration of thiobarbituric acid reactive substances (TBARS) in the muscle of animals from the trauma group (+233%), and this increase was eliminated by PRF administration. Superoxide dismutase (SOD) activity was increased (+411%) by trauma, resulting in significantly higher consumption of catalase (-72%), while PRF administration brought both of these markers back to levels close to those of the control group. Trauma induced considerable production of interleukins TNF-α, IL-1ß, and IL-6 (+215%, +262%, and +326% vs. controls, respectively) and these effects were also significantly reduced by PRF administration. CONCLUSIONS: In total, PRF inhibits oxidative stress and restores antioxidant enzymes to control levels and may block production of inflammatory markers in muscles of animals subjected to trauma. By modulating redox equilibrium, PRF treatment might block production of noxious mediators involved in development of trauma-induced injury.

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In the last two decades, due to the development of the information society, the massive increase in the use of information technologies, including the connection and communication of multiple electronic devices, highlighting Wi-Fi networks, as well as the emerging technological advances of 4G and 5G (new-generation mobile phones that will use 5G), have caused a significant increase in the personal exposure to Radiofrequency Electromagnetic Fields (RF-EMF), and as a consequence, increasing discussions about the possible adverse health effects. The main objective of this study was to measure the personal exposure to radiofrequency electromagnetic fields from the Wi-Fi in the university area of German Jordanian University (GJU) and prepare georeferenced maps of the registered intensity levels and to compare them with the basic international restrictions. Spot measurements were made outside the university area at German Jordanian University. Measurements were made in the whole university area and around two buildings. Two Satimo EME SPY 140 (Brest, France) personal exposimeters were used, and the measurements were performed in the morning and afternoon, and on weekends and weekdays. The total average personal exposure to RF-EMF from the Wi-Fi band registered in the three study areas and in the four days measured was 28.82 µW/m2. The average total exposure from the Wi-Fi band registered in the ten measured points of the university area of GJU was 22.97 µW/m2, the one registered in the eight measured points of building H was 34.48 µW/m2, and the one registered in the eight points of building C was 29.00 µW/m2. The maximum average values registered in the campus of GJU are below the guidelines allowed by International Commission on Non-ionizing Radiation Protection (ICNIRP). The measurement protocol used in this work has been applied in measurements already carried out in Spain and Mexico, and it is applicable in university areas of other countries.

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INTRODUCCIÓN: Hasta el momento, los resultados de distintas investigaciones sobre la exposición a Radiofrecuencias y sus consecuencias biológicas, son contradictorios. Nuestro estudio nace como un estudio de replicación, en conjunto con investigadores de la Escuela de Tecnología de la Salud de Lisboa, Lisboa, Portugal. Adoptamos el mismo diseño de estudio, para verificar si los resultados de su evaluación de la frecuencia de micronucleos (MN) en los usuarios de teléfonos móviles eran comparables a los resultados obtenidos en este estudio similar en Córdoba, Argentina. MATERIALES Y METODOS: Para estudiar el daño del ADN por la exposición a radiofrecuencia asociada con el teléfono celular se estudiaron los MN (marcadores celulares de daño genómico) en células bucales exfoliadas, extraídas de frotis de células de las mejillas internas derecha e izquierda de usuarios de teléfonos celulares en 83 voluntarios sanos de 18 a 36 años. Las frecuencias de MN fueron analizadas por la duración y el lado preferencial de uso del teléfono celular. RESULTADOS: no se observó relación entre la frecuencia de MN y la duración del uso como tampoco con el lado preferencial. CONCLUSION: nuestros resultados sugieren que la exposición a radiofrecuencia en los niveles observados no induce la formación de MN en células bucales. (AU)

INTRODUCTION: the results of various research on radiofrequency exposure and its biological consequences are contradictory. Taking into account this reasoning, our study was born as a replication study, together with researchers from the School of Health Technology of Lisbon, Lisbon, Portugal. We adopted the same study design, to verify if the results of your evaluation of the frequency of micronuclei (MN) in cell phone users were comparable to the results obtained in this similar study in Cordoba, Argentina. MATERIALS AND METHODS: To study ADN damage from radiofrequency exposure associated with cell phone, MN (cell markers of genomic damage) were studied in exfoliated buccal cells, extracted from right and left internal cheek cell smears of cell phone in 83 healthy volunteers from 18 to 36 years. RESULTS: The MN frequencies were analyzed by the duration and the preferential side of use of the cell phone. No relationship was observed between the MN frequency and the duration of use as well as the preferential side. CONCLUSION: our results suggest that exposure to radiofrequency in the observed levels does not induce the formation of MN in buccal cells. (AU)

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