Electromagnetic field exposure as a plausible approach to enhance the proliferation and differentiation of mesenchymal stem cells in clinically relevant scenarios / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

Mesenchymal stem/stromal cell (MSC)‍-based therapy has been regarded as one of the most revolutionary breakthroughs in the history of modern medicine owing to its myriad of immunoregulatory and regenerative properties. With the rapid progress in the fields of osteo- and musculoskeletal therapies, the demand for MSC-based treatment modalities is becoming increasingly prominent. In this endeavor, researchers around the world have devised new and innovative techniques to support the proliferation of MSCs while minimizing the loss of hallmark features of stem cells. One such example is electromagnetic field (EMF) exposure, which is an alternative approach with promising potential. In this review, we present a critical discourse on the efficiency, practicability, and limitations of some of the relevant methods, with insurmountable evidence backing the implementation of EMF as a feasible strategy for the clinically relevant expansion of MSCs.

Low-frequency pulsed electromagnetic fields promote osteoblast mineralization and maturation of rats through the PC2/sAC/PKA/CREB signaling pathway / 南方医科大学学报

OBJECTIVE@#To explore whether the effect of low-frequency pulsed electromagnetic fields (PEMFs) in promoting osteoblast mineralization and maturation is related to the primary cilia, polycystin2 (PC2) and sAC/PKA/CREB signaling pathway.@*METHODS@#We detected the expression levels of PC2, sAC, PKA, CREB and their phosphorylated proteins in primary rat calvarial osteoblasts exposed to 50 Hz 0.6 mT PEMFs for 0, 5, 15, 30, 60, 90, and 120 min. We blocked PC2 function with amiloride hydrochloride and detected the changes in the activity of sAC/PKA/CREB signal pathway and the mineralization and maturation of the osteoblasts. These examinations were repeated in the osteoblasts after specific knockdown of PC2 via RNA interference and were the co-localization of PC2, sAC, PKA, CREB and their phosphorylated proteins with the primary cilia were using immunofluorescence staining. The expressions of PC2 and the signaling proteins of sAC/PKA/CREB pathway were detected after inhibition of primary ciliation by RNA interference.@*RESULTS@#The expression levels of PC2, sAC, p-PKA and p- CREB were significantly increased in the osteoblasts after exposure to PEMFs for different time lengths (P < 0.01). Blocking PC2 function or PC2 knockdown in the osteoblasts resulted in failure of sAC/PKA/CREB signaling pathway activation and arrest of osteoblast mineralization and maturation. PC2, sAC, p-PKA and p-CREB were localized to the entire primary cilia or its roots, but PKA and CREB were not detected in the primary cilia. After interference of the primary cilia, PEMFs exposure no longer caused increase of PC2 expression and failed to activate the sAC/PKA/CREB signaling pathway or promote osteoblast mineralization and maturation.@*CONCLUSION@#PC2, located on the surface of the primary cilia of osteoblasts, can perceive and transmit the physical signals from PEMFs and promote the mineralization and maturation of osteoblasts by activating the PC2/ sAC/PKA/CREB signaling pathway.

Effect of polycystin2 on differentiation and maturation of osteoblasts promoted by low-frequency pulsed electromagnetic fields / 生物工程学报

It is known that low-frequency pulsed electromagnetic fields (PEMFs) can promote the differentiation and maturation of rat calvarial osteoblasts (ROBs) cultured in vitro. However, the mechanism that how ROBs perceive the physical signals of PEMFs and initiate osteogenic differentiation remains unknown. In this study, we investigated the relationship between the promotion of osteogenic differentiation of ROBs by 0.6 mT 50 Hz PEMFs and the presence of polycystin2 (PC2) located on the primary cilia on the surface of ROBs. First, immunofluorescence staining was used to study whether PC2 is located in the primary cilia of ROBs, and then the changes of PC2 protein expression in ROBs upon treatment with PEMFs for different time were detected by Western blotting. Subsequently, we detected the expression of PC2 protein by Western blotting and the effect of PEMFs on the activity of alkaline phosphatase (ALP), as well as the expression of Runx-2, Bmp-2, Col-1 and Osx proteins and genes related to bone formation after pretreating ROBs with amiloride HCl (AMI), a PC2 blocker. Moreover, we detected the expression of genes related to bone formation after inhibiting the expression of PC2 in ROBs using RNA interference. The results showed that PC2 was localized on the primary cilia of ROBs, and PEMFs treatment increased the expression of PC2 protein. When PC2 was blocked by AMI, PEMFs could no longer increase PC2 protein expression and ALP activity, and the promotion effect of PEMFs on osteogenic related protein and gene expression was also offset. After inhibiting the expression of PC2 using RNA interference, PEMFs can no longer increase the expression of genes related to bone formation. The results showed that PC2, located on the surface of primary cilia of osteoblasts, plays an indispensable role in perceiving and transmitting the physical signals from PEMFs, and the promotion of osteogenic differentiation of ROBs by PEMFs depends on the existence of PC2. This study may help to elucidate the mechanism underlying the promotion of bone formation and osteoporosis treatment in low-frequency PEMFs.

Biomateriales compuestos para restauración ósea obtenidos mediante tecnologías basadas en el uso del campo electromagnético / Composite biomaterials for bone restoration obtained by technologies based on the use of the electromagnetic

Introducción: El panorama demográfico en el mundo está cambiando. La población mayor de 60 años es el segmento que está creciendo más rápidamente y en el que las enfermedades del tejido óseo se presentan con más frecuencia, lo que aumenta la demanda de materiales y tecnologías apropiadas para restaurar estos tejidos. Objetivo: Analizar la información que se ha generado sobre el desarrollo de biomateriales compuestos para la reparación ósea, con énfasis en la identificación de las tecnologías emergentes basadas en el uso del campo electromagnético, sus aplicaciones y potencialidades. Métodos: Se consultaron trabajos científicos publicados en libros, revistas, patentes y tesis. El 80 por ciento de la documentación seleccionada pertenece al periodo 2010-2019. Análisis e integración de la información: Los métodos identificados fueron clasificados en cinco grupos: electrodeposición química, ya sea por electrólisis, electroforesis o síntesis electroforética in situ; electroporación; electrohilado; control magnético distal y bioestimulación electromagnética de células y tejidos, directamente o por la introducción de dispositivos que convierten la energía electromagnética en energía mecánica. Conclusiones: Estos métodos permiten la conformación de matrices celulares y acelulares compuestas y, además, dispositivos bioestimuladores con control de los parámetros de construcción y acción, de tal manera, que se logran procesos con mayor grado de reproducibilidad y a la medida de los requerimientos específicos para cada paciente(AU)

Introduction: The global demographic panorama is changing. The population aged over 60 years is the fastest growing segment, as well as the one where bone tissue diseases are most common, increasing the demand of appropriate materials and technologies to restore those tissues. Objective: To analyze the information so far generated about the development of composite biomaterials for bone repair, with an emphasis on the identification of emerging technologies based on the use of the electromagnetic field, its applications and potential. Methods: An analysis was performed of scientific papers published in books, journals, patents and theses. Of the documentation selected, 80 percent was from the period 2010-2019. Data analysis and integration: The methods identified were classified into five groups: chemical electrodeposition, be it by in situ electrophoretic synthesis, electrolysis or electrophoresis; electroporation; electrospinning; distal magnetic control and electromagnetic biostimulation of cells and tissues, either directly or incorporating devices which convert electromagnetic energy into mechanical energy. Conclusions: These methods permit the conformation of composite cellular and acellular matrices as well as biostimulator devices controlling construction and action parameters in such a way that the processes obtained display greater reproducibility and are more in keeping with the specific requirements of each patient(AU)

Exposure to electromagnetic field, cell phone use behaviors, SAR values, and changes in health following exposure in adolescent university students / Exposição ao campo eletromagnético, comportamentos de uso de telefones celulares, valores SAR mudanças na saúde após exposição em estudantes universitários adolescentes

ABSTRACT Background: The use of technological devices is growing rapidly, and the use of cell phones increases in parallel. Dependence on technological devices is a particular factor in this increased exposure. Many studies have been performed on this electromagnetic field, but no definite conclusions have been drawn. Objective: The purpose of this research was to investigate exposure to electromagnetic field, cell phone use behaviors, the specific absorption rate (SAR) values, and changes in health occurring after exposure in university students. Methods: A questionnaire was administered to 1,019 volunteer students aged 18-24 years at the Niğde Ömer Halisdemir and Recep Tayip Erdoğan Universities in 2018-2019. The questions were based on a survey of the literature. Results: The students spent an average 4-8 hours per day on their cell phones, and findings such as headache (p=0.002), concentration deficit (p=0.001), tiredness on waking in the morning (p=0.001), hyperactivity (p=0.001), general feeling of fatigue (p=0.001), and lethargy (p=0.001) increased in a statistically significant manner with length of use. Conclusions: Participants exhibited high levels of cell phone use and experienced biological, behavioral, and sleep problems. They also had very little knowledge about specific SAR values, an important criterion concerning cell phones.

RESUMO Introdução: O uso de dispositivos tecnológicos está crescendo rapidamente e o uso de telefone celulares aumenta em paralelo. A dependência de dispositivos tecnológicos é um fator nesse aumento de exposição. Diversos estudos sobre o campo eletromagnético foram realizados, mas nenhuma conclusão definitiva foi alcançada. Objetivo: O objetivo desta pesquisa foi investigar a exposição ao campo eletromagnético, os comportamentos de uso do telefone celular, os valores de absorção específica (specific absorption rate — SAR) dos telefones celulares utilizados e as alterações na saúde ocorridas após a exposição em adolescentes universitários. Métodos: Um questionário foi aplicado a 1.019 alunos voluntários com idades entre 18-24 anos nas universidades Niğde Ömer Halisdemir e Recep Tayip Erdoğan em 2018-2019. As perguntas foram baseadas em um levantamento bibliográfico. Resultados: Os estudantes gastaram em média 4-8 horas por dia em seus celulares, e achados como cefaleia (p=0,002), dificuldade de concentração (p=0,001), cansaço ao acordar pela manhã (p=0,001), hiperatividade (p=0,001), sensação geral de fadiga (p=0,001) e letargia (p=0,001) aumentaram de forma estatisticamente significativa com o tempo de uso. Conclusões: Os participantes exibiram altos níveis de uso de telefone celular e problemas biológicos, comportamentais e de sono. Eles também tinham pouco conhecimento sobre valores específicos de SAR, um critério importante para telefones celulares.

A new strategy for the treatment of osteonecrosis of the femoral head / 中国组织工程研究

BACKGROUND: Research evidence shows hip arthroplasty has become the final treatment of osteonecrosis of femoral head, but early-and middle-stage osteonecrosis of femoral head or young patients often give priority to hip preservation treatment, including conservative treatment and surgical treatment. OBJECTIVE: To summarize the progress of hip preservation in the treatment of osteonecrosis of femoral head. METHODS: The literature about hip-preserving treatment of osteonecrosis of femoral head in PubMed, VIP, CNKI and Web of Science databases from 2010 to March 2020 was searched by computer. The key words were “osteonecrosis of femoral head, hyperbaric oxygen, pulsed electromagnetic fields, extracorporeal shock wave, hip arthroscopy, core decompression, stem cell transplantation, non-vascularized free bone grafting, vascularized free bone grafting, porous tantalum rod implantation, intertrochanteric osteotomy, medication”. A total of 197 articles were retrieved, and the full text was consulted. According to the inclusion criteria, 59 articles were included for result analysis. RESULTS AND CONCLUSION: (1) Drug therapy should be used cautiously because of its potential side effects and insufficient research. (2) Physiotherapy is effective for early lesions, and it has the advantages of non-invasion and convenient operation. (3) At present, there are different types of hip preservation surgery. Core decompression is the basic therapy for the treatment of osteonecrosis of femoral head, but it is seldom used alone. At present, it is often treated in combination with other hip preservation therapies. Osteotomy has higher requirements in the selection of patients’ indications and surgical skills, so it should be chosen carefully in clinic. There are some problems in porous tantalum rod implantation, such as long operation time, large blood loss and difficulty of hip replacement in the later stage. Stem cells and arthroscopic therapy show good results, and the research process should be accelerated. Vascularized bone grafting has a good effect on both middle-and late-stage patients.

Artrodesis transcalcánea con injerto libre del peroné por seudoartrosis de tibia distal / Transcalcaneal Arthrodesis with Free Fibula Graft for Distal Tibial Nonunion

RESUMEN Introducción: Las fracturas abiertas del tercio distal de tibia o pilón son poco frecuentes, en nuestro medio se producen por traumas de alta energía como los accidentes de tránsito, y pueden ser de distintos grados según su envergadura. Entre las complicaciones frecuentes están la seudoartrosis, deformidades y artritis postraumática. Cuando el dolor es refractario a los analgésicos están indicadas las artrodesis. Objetivo: Presentar los resultados del tratamiento realizado en un paciente con seudoartrosis distal de tibia y artritis postraumática del tobillo, dolorosa, con gran lesión de partes blandas, por lo que fue imposible realizar los procedimientos quirúrgicos habituales. Presentación del caso: Se realizó artrodesis de las articulaciones tibio-peronea-astragalina-calcánea, mediante un injerto libre del peroné autólogo, compresión, y estabilización con un fijador externo RALCA®; se asoció un campo electromagnético pulsátil para acelerar la formación del callo óseo y disminuir el dolor posquirúrgico. Durante dos años se le hizo seguimiento. Conclusiones: Se logró el objetivo del tratamiento al fusionar la articulación tibiotarsiana, comenzar el apoyo precoz y su capacidad funcional. Los resultados demuestran además los beneficios de la compresión realizada con los fijadores externos en las artrodesis; el uso del campo electromagnético asociado aceleró la osteogénesis, se consiguió la consolidación ósea, la estabilización, disminuyó el edema y el dolor, además la reincorporación del paciente a la sociedad. No se encontró en la bibliografía revisada otra técnica quirúrgica similar(AU)

ABSTRACT Introduction: Open fractures of the distal third of the tibia or pilon are rare, in our environment they are caused by high-energy traumas such as traffic accidents, and can be of different degrees depending on their size. Common complications include nonunion, deformities, and post-traumatic arthritis. When pain is refractory to analgesics, arthrodesis is indicated. Objective: To report the results of the treatment carried out in a patient with distal tibial pseudoarthrosis and post-traumatic arthritis of the ankle, painful, with a large soft tissue injury, which made it impossible to perform the usual surgical procedures. Case report: Arthrodesis of the tibiofibular-talar-calcaneal joints was performed, using a free graft of the autologous fibula, compression, and stabilization with a RALCA® external fixator. A pulsatile electromagnetic field was associated to accelerate bone callus formation and reduce postoperative pain. This patient was followed up for two years. Conclusions: The treatment objective was achieved by fusing the tibiotarsal joint, by starting early support and functional capacity. The results also prove the benefits of compression performed with external fixators in arthrodesis. The use of the associated electromagnetic field accelerated osteogenesis, bone consolidation and stabilization were achieved, edema and pain decreased, as well as the patient's reincorporation into society. No other similar surgical technique was found in the reviewed literature(AU)

Pulsed electromagnetic fields stimulation combined with sclerostin antibody improves bone metabolism and bone microstructure in postmenopausal osteoporosis rabbits / 中国组织工程研究

BACKGROUND: Both pulsed electromagnetic fields (PEMF) stimulation and sclerostin antibody (Scl-Ab) have good effects on the bone metabolism of ovariectomized (OVX) New Zealand rabbits, but research on the combined intervention of PEMF and Scl-Ab in the OVX rabbits is rarely reported. OBJECTIVE: To explore the effect of PEMF combined with Scl-Ab on postmenopausal osteoporosis and to explore the therapeutic value for osteoporosis. METHODS: An animal model of postmenopausal osteoporosis was made in New Zealand white rabbits after ovariectomy. The experimental animals were randomly divided into OVX control group, PEMF group, Scl-Ab group and PEMF+Scl-Ab group, with 10 rats in each group. On the 1st day after surgery, the PEMF group was given PEMF magnetic therapy once a day; the Scl-Ab group was given subcutaneous injection of Scl-Ab twice a week; the PEMF+Scl-Ab group received PEMF magnetic therapy once a day, five times a week, and Scl-Ab subcutaneous injections twice a week; the OVX group was injected subcutaneously with the same dose of normal saline twice a week for 8 weeks. After 8 weeks of treatment, bone metabolism index, bone mineral density, and MicroCT bone microstructure parameters were detected. All animal procedures were approved by the Department of Experimental Animal Science, Fudan University (approval No. 20171263A193). RESULTS AND CONCLUSION: Bone mineral density was significantly decreased in the New Zealand white rabbits after 6 months of OVX, suggesting that the osteoporosis model was successfully established. Compared with the OVX group, the bone mineral density of the L3 vertebral body in the PEMF group, the Scl-Ab group and the PEMF+Scl-Ab group increased significantly (P < 0.05). Compared with the OVX group, serum bone-specific alkaline phosphatase levels were significantly higher, and serum tartrate-resistant acid phosphatase 5b levels were significantly lower in the PEMF group, the Scl-Ab group and the PEMF+Scl-Ab group. The serum tartrate-resistant acid phosphatase 5b level in the PEMF+Scl-Ab group was significantly lower than that in the PEMF group and the Scl-Ab group. The bone metabolism index and bone microstructural parameters (bone volume fraction, trabecular thickness, trabecular number, and trabecular separation) of the PEMF+Scl-Ab group were significantly better than those of the PEMF group and the Scl-Ab group (all P < 0.05). These findings indicate that the combination of Scl-Ab and PEMF can enhance bone mineral density and improve bone metabolism and bone microstructure in postmenopausal osteoporosis New Zealand white rabbits.

Quantum Physics Perspective on Electromagnetic and Quantum Fields Inside the Brain

@#Brain energy is associated commonly with electrochemical type of energy. This energy is displayed in the form of electromagnetic waves or better known as brainwaves. This concept is a classical concept (Newtonian) in which the studied object, that is the brain is viewed as a large anatomical object with its functional brainwaves. Another concept which incorporates quantum principles in it can also be used to study the brain. This perspective viewing the brain as purely waves, including its anatomical substrate. Thus, there are two types of energy or field exist in our brain: electromagnetic and quantum fields. Electromagnetic field is thought as dominant energy in purely motor and sensory inputs to our brain, whilst quantum field or energy is perceived as more influential in brain cognitions. The reason for this notion lies in its features which is diffused, nondeterministic, varied, complex and oneness.

Efficacy of low frequency pulsed electromagnetic field therapy in treatment of peritumoral edema of glioma / 上海预防医学

Objective To evaluate the efficacy of low frequency pulsed electromagnetic field (LFPEMF) on peritumoral edema in patients with glioma, providing a theoretical basis for clinical treatment of peritumoral edema. Methods This study included 32 patients with recurrent cerebral glioma with peritumoral edema after the operation of glioma in department of glioma, Beijing Shijitan Hospital, Capital Medical University from March 2017 to December 2018.The period of LFPEMF treatment was 10-14 days.The clinical symptoms related to brain edema were recorded before and after treatment.The National Institutes of Health Stroke Scale (National Institute of health stroke scale, NIHSS), Karnofsky quality of life score (KPS), brain edema and tumor range in cranial MRI, T lymphocyte subgroup CD4+/CD8+, superoxide dismutase (SOD) were recorded.The SPSS21.0 statistical analysis software was used to carry out analysis by using self controlled study.P < 0.05 was statistically significant. Results After the treatment of LFPEMF, the results showed that LFPEMF was effective in 25 patients, invalid in 7 patients, and the total effective percentage was 78.13%.The area of brain edema was significantly improved after using LFPEMF(P < 0.05).There was no significant improvement in the area of brain tumor after using LFPEMF therapy (P>0.05).KPS and NIHSS scores improved significantly after using LFPEMF (P < 0.05). Conclusion In the patients with peritumoral edema of glioma, the application of LFPEMF in the patients′ Yongquan point and Lao Gong point can reduce peritumoral edema, and improve clinical symptoms.

Efficacy of low frequency pulsed electromagnetic field therapy in treatment of peritumoral edema of glioma / 上海预防医学

Objective To evaluate the efficacy of low frequency pulsed electromagnetic field (LFPEMF) on peritumoral edema in patients with glioma, providing a theoretical basis for clinical treatment of peritumoral edema. Methods This study included 32 patients with recurrent cerebral glioma with peritumoral edema after the operation of glioma in department of glioma, Beijing Shijitan Hospital, Capital Medical University from March 2017 to December 2018.The period of LFPEMF treatment was 10-14 days.The clinical symptoms related to brain edema were recorded before and after treatment.The National Institutes of Health Stroke Scale (National Institute of health stroke scale, NIHSS), Karnofsky quality of life score (KPS), brain edema and tumor range in cranial MRI, T lymphocyte subgroup CD4+/CD8+, superoxide dismutase (SOD) were recorded.The SPSS21.0 statistical analysis software was used to carry out analysis by using self controlled study.P < 0.05 was statistically significant. Results After the treatment of LFPEMF, the results showed that LFPEMF was effective in 25 patients, invalid in 7 patients, and the total effective percentage was 78.13%.The area of brain edema was significantly improved after using LFPEMF(P < 0.05).There was no significant improvement in the area of brain tumor after using LFPEMF therapy (P>0.05).KPS and NIHSS scores improved significantly after using LFPEMF (P < 0.05). Conclusion In the patients with peritumoral edema of glioma, the application of LFPEMF in the patients′ Yongquan point and Lao Gong point can reduce peritumoral edema, and improve clinical symptoms.

Effect of Luteolin on Biochemical, Immunohistochemical, and Morphometrical Changes in Rat Spinal Cord following Exposure to a 900 MHz Electromagnetic Field / 生物医学与环境科学（英文）

Objective@#This study aimed to investigate the effect of exposure to a 900 MHz electromagnetic field (EMF) on the cervical spinal cord (CSC) of rats and the possible protective effect of luteolin (LUT) against CSC tissue damage.@*Methods@#Quantitative data were obtained stereological, biochemical, immunohistochemical, and histopathological techniques. We investigated morphometric value, superoxide dismutase (SOD) level, and the expression of high-mobility group box 1 protein molecules, as well as histological changes.@*Results@#The total number of motor neurons in the EMF group significantly decreased in comparison with that in the control group ( < 0.05). In the EMF + LUT group, we found a significant increase in the total number of motor neurons compared with that in the EMF group ( < 0.05). SOD enzyme activity in the EMF group significantly increased in comparison with that in the control group ( < 0.05). By contrast, the EMF+LUT group exhibited a decrease in SOD level compared with the EMF group ( < 0.05).@*Conclusion@#Our results suggested that exposure to EMF could be deleterious to CSC tissues. Furthermore, the protective efficacy of LUT against SC damage might have resulted from the alleviation of oxidative stress caused by EMF.

The effect of very low dose pulsed magnetic waves on cochlea / Efeito de ondas magnéticas pulsadas de dosagem extremamente baixa na cóclea

Abstract Introduction: In daily life biological systems are usually exposed to magnetic field forces at different intensities and frequencies, either directly or indirectly. Despite negative results, the therapeutic use of the low dose magnetic field has been found in recent studies. The effect of magnetic field forces on cochlear cells is not clear in the literature. Objective: In our study, we first applied in vivo pulsed magnetic fields to laboratory rats to investigate the effects on cochlea with distortion product otoacoustic emission test followed by histopathological examinations. Methods: Twelve rats were included in this study, separated into two groups as study group and control group. The rats in the study group were exposed to 40 Hz pulsed magnetic field for 1 h/day for 30 days; the hearing of the rats was controlled by otoacoustic emission test. Also, their cochleas were removed and histochemical examination was performed by Caspase-3, Caspase-9, and TUNEL methods. Results: A statistically significant difference was determined (p < 0.05) when the hearing thresholds of the groups obtained by using 5714 Hz and 8000 Hz stimuli were compared by Kruskal-Wallis test. A significant reaction was observed in the study group, especially in the outer ciliated cells during immunohistochemical examinations by using Caspase-3 and Caspase-9 methods. A significantly positive difference was determined in the study group, especially at the outer ciliated cells and the support cells of the corti organ, when compared to the control group (p < 0.05) by the TUNEL method. Conclusion: According to the results of our study, the very low dose magnetic field, which is considered to be used for therapeutic purposes recently, can cause both auditory function defects and histopathologic damage in cochlear cells.

Resumo Introdução: Os sistemas biológicos são geralmente expostos a forças de campo magnético em diferentes intensidades e frequências, direta ou indiretamente, na vida diária. Apesar dos resultados negativos, o uso terapêutico do campo magnético de baixa dose tem sido encontrado em estudos recentes. O efeito das forças do campo magnético sobre as células cocleares não está claro na literatura. Objetivo: Em nosso estudo, aplicamos pela primeira vez campos magnéticos pulsados in vivo em ratos de laboratório para investigar os efeitos na cóclea através do teste de emissão otoacústica por produto de distorção e análises histopatológicas. Método: Doze ratos foram incluídos neste estudo, os quais foram separados em dois grupos, grupo de estudo e grupo controle. Os ratos do grupo de estudo foram expostos a campo magnético pulsado de 40 Hz por 1 hora/dia por 30 dias, e a audição dos ratos foi controlada por testes de emissão otoacústica. Além disso, suas cócleas foram colhidas e o exame histoquímico foi feito pelos métodos caspase-3, caspase-9 e TUNEL. Resultados: Foi determinada uma diferença estatisticamente significante (p < 0,05) quando os limiares auditivos dos grupos obtidos por meio dos estímulos de 5714 Hz e 8000 Hz foram comparados pelo teste de Kruskal-Wallis. Uma reação significante foi observada no grupo de estudo, especialmente nas células ciliadas externas nas análises imuno-histoquímicas, com os métodos caspase-3 e caspase-9. Uma diferença significantemente positiva foi determinada no grupo de estudo, especialmente nas células ciliadas externas e nas células de suporte do órgão de Corti, quando comparadas com o grupo controle (p < 0,05) pelo método TUNEL. Conclusão: De acordo com os resultados do nosso estudo, o campo magnético de dose baixa, que tem sido considerado para uso terapêutico recentemente, pode causar defeitos na função auditiva e danos histopatológicos nas células cocleares.

The effects of mobile phone exposure on mast cells in rat dura mater / Efectos de la exposición del teléfono móvil en los mastocitos de la duramadre de ratas

Mobile phone use has increased rapidly. The central nervous system has been shown to be adversely affected by its electromagnetic field (EMF) resulting in headache and sleep disturbances. How the cells make up the CNS and are affected by EMF is unclear. However, because of their central role in inflammation through diverse stimuli including radiation, this study aimed to investigate the effects of electromagnetic fields induced by mobile phones on mast cells in rat dura mater. A total of 18 adult, female, SpragueDawley rats were divided into two groups. The choice of female rats for his study was based on recent surveys demonstrating that mobile phone use is more frequent and prolonged among females. The study group was exposed to 900 MHz electromagnetic field (1 h/day for 45 days). In the end of the study, duramater tissue was extracted and stained using Toluidine blue. Mast cells were counted and results were analysed using Student t test. Mean mast cell number was 202.33±9.82 and 456.78±35.01 in the control and study groups, respectively (p<0.05). Analysis of serum electrolyte and immunoglobulin E levels showed no statistically significant difference between the two groups (p>0.05). The study showed that mobile phone exposure increased mast cell number and degranulation in rat dura mater. Further studies are required to evaluate the clinical implications of these findings.

El uso del teléfono móvil ha aumentado rápidamente. Se ha demostrado que el sistema nervioso central (SNC) se ve afectado de manera adversa debido al campo electromagnético (CEM) que produce dolor de cabeza y trastornos del sueño. No está claro cómo se ve afectada la composición celular del SNC por el CEM. Sin embargo, debido a su función principal en la inflamación a través de diversos estímulos que incluyen la radiación, este estudio tuvo como objetivo investigar los efectos de los campos electromagnéticos inducidos por los teléfonos móviles en los mastocitos de la duramadre de ratas. Un total de 18 ratas Sprague-Dawley adultas, hembras, se dividieron en dos grupos. Se usaron ratas hembras para este estudio en base a investigaciones recientes que han demostrado que el uso de teléfonos móviles es más frecuente y prolongado en las mujeres. Los grupos de estudio fueron expuestos a un campo electromagnético de 900 MHz (1 h / día durante 45 días). Al término del estudio, fue extirpado el tejido de la duramadre y teñido con azul de toluidina. Se contaron los mastocitos y se analizaron los resultados utilizando la prueba t de Student. La cantidad media de células cebadas fue de 202,33 ± 9.82 y 456,78 ± 35,01 en los grupos control y estudio, respectivamente (p <0,05). El análisis del electrolito sérico y los niveles de inmunoglobulina E no mostraron diferencias estadísticamente significativas entre los dos grupos (p> 0,05). El estudio mostró que la exposición a teléfonos móviles aumentó el número de mastocitos y la desgranulación en la duramadre de las ratas. Se requieren estudios adicionales para evaluar las implicaciones clínicas de estos hallazgos.

Bedroom design orientation and sleep electroencephalography signals

Background: Orientation is a significant factor in architectural design that may affect well-being. Body direction does not change during sleeping, and sleeping is sensitive and affected by environmental factors. Aims: This neuroarchitecture study aimed to assess the effects of bed orientation on sleep quality to enhance bedroom design. Materials and Methods: To do so, the effects of earth's electromagnetic field (EMF) on sleep electroencephalography (EEG) signals were evaluated using signal processing techniques. In this cross-sectional study, a total of 21 healthy volunteer participants slept for two consecutive naps, at two rooms with identical interior design and different bed orientations, toward and against earth's EMF in a sleep clinic. Statistical Analysis: In this experiment, discrete wavelet transform extracted five subfrequencies of EEG data as delta, theta, alpha, beta1, and beta2. In addition, the energy signals were computed by measurement of wave frequencies. The mean total sleep time was 1.63 h in North–South (N-S) earth's EMF orientation and 1.38 h in the other direction. Results: t-test results showed significant changes in delta, theta, and alpha frequencies in terms of bed orientation. There was a significant result in the alpha energy ratio over the whole signal energy. Furthermore, there were increases in the average energy of delta, theta, and alpha bands in N-S versus East–West (E-W) bed directions. Conclusions: This study indicated that sleep in N-S direction could be more beneficial than E-W and the sleep EEG signals can be sensitive to earth's EMF. The results show the importance of considering orientation in bedroom design and its benefits on inhabitants' well-being.

Inhibitory effect of extremely low frequency-electromagnetic field combined with static magnetic field on tumor cell proliferation and the possible mechanism / 肿瘤

Objective: To investigate the inhibitory effect of a combination of static magnetic field (SMF) and extremely low frequency-electromagnetic field (ELF-EMF) on the proliferation of tumor cells, and its causal relationship with the induction of intracellular reactive oxygen species (ROS) after exposure. Methods: The intensities of SMF and 50 Hz ELF-EMF both changed periodically and generated a magnetic field (MF) with a time-averaged intensity of 5.1 mT in the center of exposure area. The bronchial epithelium of human lung Beas-2B cells, human renal epithelial 293T cells, human nephroblastoma G401 cells, human gastric adenocarcinoma AGS cells, human pancreatic cancer BxPC cells and human neuroblastoma CHLA255 cells were exposured in MF for 2 h/d (continuous 3 days). The effects of the combined MF on the growth, proliferation, apoptosis and intracellular ROS concentration were detected by trype blue method, BrdU method, FCM method and DCFH-DA fluorescence probe method, respectively. Results: This combined MF showed no inhibitory effect on non-tumor cells including Beas-2B and 293T (both P > 0.05), while it showed inhibitory effect on tumor cells including G401, AGS, BxPC, and CHLA255 cells (all P < 0.01). G401 and CHLA255 cells were more sensitive to the MF, the inhibitory rate of G401 and CHLA255 cells at the third day of exposure was (29.41±0.81)% and (31.71±4.59)%, respectively. The apoptosis rate of G401 cells exposed to MF for 2 h/d was increased in 3 days (P < 0.05, P < 0.01 and P < 0.01). As compared with daily exposure for 2 h, the inhibition rate of daily exposure for 8 h induced another 10% increase (all P < 0.01). Furthermore, the combined MF exhibited more pronounced antitumor effect than that of SMF or ELF-EMF alone, including SMF with the same intensity of the combined field (all P < 0.01). The peak of intracellular ROS levels was reached shortly after initial exposure (1-2 h), for long before the peak of cell inhibition was reached (day 2-3 with accumulated exposure of 4-6 h). Continuous or intermittent increase of MF exposure did not result in further accumulation of intracellular ROS. However, the peak of ROS levels persisted to the next day after termination of exposure. Both SMF and ELF-EMF could induce the elevation of ROS, but without superimposition effect. Conclusion: Extending the exposure time of MF can improve its inhibitory effect on tumor cells. The antitumor effect of the combined MF is related to free radical damage, but this may be not the only mechanism.

Impacts of electromagnetic radiation from cellphones and Wi-Fi on spermatogenesis / 中华男科学杂志

With the development of Wi-Fi technology and widespread exposure to electromagnetic radiation (EMR), people are increasingly concerned about the health hazards caused by radiofrequency electromagnetic fields as from cellphones and Wi-Fi, particularly about the current decline in sperm concentration and increase in male infertility. Long-term exposure to EMR not only damages male reproductive organs, but also affects the number, morphology, motility and oocyte-binding ability of sperm, and indirectly increases the risk of infertility. However, EMR is not unavoidable. Low-intensity short-term or intermittent exposure to EMR has little adverse effect on reproductive organs and sperm. And many antioxidant and anti-free radical agents, such as vitamin E and melatonin, can protect some special populations from EMR. This review presents an overview of the impacts of EMR from cellphones and Wi-Fi on sperm, some countermeasures, and prospects of EMR protection.

Possible Effects of Radiofrequency Electromagnetic Field Exposure on Central Nerve System

Technological advances of mankind, through the development of electrical and communication technologies, have resulted in the exposure to artificial electromagnetic fields (EMF). Technological growth is expected to continue; as such, the amount of EMF exposure will continue to increase steadily. In particular, the use-time of smart phones, that have become a necessity for modern people, is steadily increasing. Social concerns and interest in the impact on the cranial nervous system are increased when considering the area where the mobile phone is used. However, before discussing possible effects of radiofrequency-electromagnetic field (RF-EMF) on the human body, several factors must be investigated about the influence of EMFs at the level of research using in vitro or animal models. Scientific studies on the mechanism of biological effects are also required. It has been found that RF-EMF can induce changes in central nervous system nerve cells, including neuronal cell apoptosis, changes in the function of the nerve myelin and ion channels; furthermore, RF-EMF act as a stress source in living creatures. The possible biological effects of RF-EMF exposure have not yet been proven, and there are insufficient data on biological hazards to provide a clear answer to possible health risks. Therefore, it is necessary to study the biological response to RF-EMF in consideration of the comprehensive exposure with regard to the use of various devices by individuals. In this review, we summarize the possible biological effects of RF-EMF exposure.

Effect of radiofrequency radiation on reproductive health

The development of cellular phone system has greatly increased the extent and magnitude of radiofrequency radiation (RFR) exposure. The RFR emitted from mobile phone and mobile phone base stations exerts thermal and non-thermal effects. The short-term and long-term exposure to RFR may have adverse effect on humans as well as animals. Most laboratory studies have indicated a direct link between exposure to RFR and adverse biological effects. Several in vitro studies have reported that RFR induces various types of cancer and DNA or chromosomal damage. On the other hand, some animal studies have not reported adverse effects of this radiation. The present review summarizes information available on the possible effects of RFR on the reproductive health.

Long term power frequency electromagnetic fields exposure influences the causal network connection pattern of local field potentials during working memory / 生物医学工程学杂志

The possible influence of electromagnetic field (EMF) on the function of neural systems has been widely concerned. In this article, we intend to investigate the effects of long term power frequency EMF exposure on brain cognitive functions and it's mechanism. The Sprague-Dawley (SD) rats were randomly divided into 3 groups: the rats in EMF Ⅰ group were placed in the 2 mT power frequency EMF for 24 days. The rats in EMF Ⅱ group were placed in the 2 mT power frequency EMF for 48 days. The rats in control group were not exposed to the EMF. Then, the 16 channel local field potentials (LFPs) were recorded from rats' prefrontal cortex (PFC) in each group during the working memory (WM) tasks. The causal networks of LFPs were also established by applying the directed transfer function (DTF). Based on that, the differences of behavior and the LFPs network connection patterns between different groups were compared in order to investigate the influence of long term power frequency EMF exposure on working memory. The results showed the rats in the EMF Ⅱ group needed more training to reach the task correction criterion (over 80%). Moreover, the causal network connection strength and the global efficiency of the rats in EMF Ⅰ and EMF Ⅱ groups were significantly lower than the corresponding values of the control group. Meanwhile, significant differences of causal density values were found between EMF Ⅱ group and the other two groups. These results indicate that long term exposure to 2 mT power frequency EMF will reduce the connection strength and the information transfer efficiency of the LFPs causal network in the PFC, as well as the behavior performance of the rats. These results may explain the effect of EMF exposure on working memory from the view of neural network connectivity and provide a support for further studies on the mechanism of the effect of EMF on cognition.