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It is important to study the relationship between extremely low-frequency magnetic fields (ELF-MFs) and childhood leukemia, particularly in locations with a high incidence of this neoplasm in children and an elevated exposure to ELF-MF, such as Mexico City. The aim was to investigate the association between ELF-MF exposure and the risk of B-lineage acute lymphoblastic leukemia (B-ALL). A case-control study was conducted in Mexico City during the period from 2010 to 2011. Residential 24-h ELF-MF measurements were obtained for 290 incident B-ALL patients and 407 controls, aged less than 16 years. Controls were frequency-matched by sex, age (±18 months), and health institution. The adjusted odds ratios (aOR) and 95% confidence intervals (CIs) were calculated. ELF-MF exposure at <0.2 µT was used to define the reference group. ELF-MF exposure at ≥0.3 µT was observed in 11.3% of the controls. Different ELF-MF intensity cutoff values were used to define the highest exposure category; the highest exposure category for each cutoff value was associated with an increased risk of B-ALL compared with the corresponding lower exposure categories. The aORs were as follows: ≥0.2 µT = 1.26 (95% CI: 0.84-1.89); ≥0.3 µT = 1.53 (95% CI: 0.95-2.48); ≥0.4 µT = 1.87 (95% CI: 1.04-3.35); ≥0.5 µT = 1.80 (95% CI 0.95-3.44); ≥0.6 µT = 2.32 (95% CI: 1.10-4.93). ELF-MF exposure as a continuous variable (per 0.2 µT intervals) was associated with B-ALL risk (aOR = 1.06; 95% CI: 1.01-1.12). In the present study, the proportion of children exposed to ≥0.3 µT is among the highest reported worldwide. Additionally, an ELF-MF exposure ≥0.4 µT may be associated with the risk of B-ALL. Bioelectromagnetics. © 2020 Bioelectromagnetics Society.

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Los neonatos pretérminos nacen con inmadurez en los órganos, lo que lleva al compromiso del sistema inmunológico. Los campos electromagnéticos afectan la producción de melatonina a niveles bajos de exposición. Estos niños necesitan equipamiento médico las 24 horas del día para su recuperación, por lo que están expuestos a los campos magnéticos durante todo el tiempo que se encuentren en la Unidad de Terapia Intensiva. El objetivo fue medir los niveles de campo magnético que se generan alrededor de cada una de las incubadoras utilizando un gaussímetro y comparar los resultados con las recomendaciones de la Comisión Internacional para la Protección contra las Radiaciones No Ionizantes de 2010 y la norma de la International Electrotechnical Commission (IEC) IEC 60601-1-2:2004. En 11 neonatos internados, los valores de radiación se encontraban dentro de los recomendados, pero existía interferencia electromagnética por problemas de disposición de los equipos en el área.

Preterm infants are born with immature organs, thus affecting the immune system. Electromagnetic fields influence melatonin production with low exposure levels. These infants require medical equipment 24/7 to recover, so they are constantly exposed to magnetic fields during their stay in the Intensive Care Unit. Our objective was to measure magnetic field levels generated around each incubator using a gauss meter and compare our results to the 2010 recommendations by the International Commission on Non-Ionizing Radiation Protection and the IEC 60601-1-2:2004 standard by the International Electrotechnical Commission (IEC). Among 11 hospitalized newborn infants, radiation was found within the recommended limits, but there was electromagnetic interference resulting from medical equipment layout problems in the unit.

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Preterm infants are born with immature organs, thus affecting the immune system. Electromagnetic fields influence melatonin production with low exposure levels. These infants require medical equipment 24/7 to recover, so they are constantly exposed to magnetic fields during their stay in the Intensive Care Unit. Our objective was to measure magnetic field levels generated around each incubator using a gauss meter and compare our results to the 2010 recommendations by the International Commission on Non-Ionizing Radiation Protection and the IEC 60601-1-2:2004 standard by the International Electrotechnical Commission (IEC). Among 11 hospitalized newborn infants, radiation was found within the recommended limits, but there was electromagnetic interference resulting from medical equipment layout problems in the unit.

Los neonatos pretérminos nacen con inmadurez en los órganos, lo que lleva al compromiso del sistema inmunológico. Los campos electromagnéticos afectan la producción de melatonina a niveles bajos de exposición. Estos niños necesitan equipamiento médico las 24 horas del día para su recuperación, por lo que están expuestos a los campos magnéticos durante todo el tiempo que se encuentren en la Unidad de Terapia Intensiva. El objetivo fue medir los niveles de campo magnético que se generan alrededor de cada una de las incubadoras utilizando un gaussímetro y comparar los resultados con las recomendaciones de la Comisión Internacional para la Protección contra las Radiaciones No Ionizantes de 2010 y la norma de la International Electrotechnical Commission (IEC) IEC 60601-1-2:2004. En 11 neonatos internados, los valores de radiación se encontraban dentro de los recomendados, pero existía interferencia electromagnética por problemas de disposición de los equipos en el área.

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Magnetic fields (MFs) have been used as an external stimulus to increase cell proliferation in chondrocytes and extracellular matrix (ECM) synthesis of articular cartilage. However, previously published studies have not shown that MFs are homogeneous through cell culture systems. In addition, variables such as stimulation times and MF intensities have not been standardized to obtain the best cellular proliferative rate or an increase in molecular synthesis of ECM. In this work, a stimulation device, which produces homogeneous MFs to stimulate cell culture surfaces was designed and manufactured using a computational model. Furthermore, an in vitro culture of primary rat chondrocytes was established and stimulated with two MF schemes to measure both proliferation and ECM synthesis. The best proliferation rate was obtained with an MF of 2 mT applied for 3 h, every 6 h for 8 days. In addition, the increase in the synthesis of glycosaminoglycans was statistically significant when cells were stimulated with an MF of 2 mT applied for 5 h, every 6 h for 8 days. These findings suggest that a stimulation with MFs is a promising tool that could be used to improve in vitro treatments such as autologous chondrocyte implantation, either to increase cell proliferation or stimulate molecular synthesis. Bioelectromagnetics. 2020;41:41-51 © 2019 Bioelectromagnetics Society.

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Temozolomide, a chemotherapeutic drug that is often administered for the treatment of brain cancer has severe side effects and a poor aqueous solubility. In order to decrease the detrimental effect of the drug over healthy cells, a novel drug delivery vehicle was developed where the therapeutic drug was encapsulated within the hydrophobic cavities of b-CD modified magnetite nanoparticles, which are embedded in chitosan nanobeads prepared by salt addition. In-vitro studies have shown that the magnetic properties of the novel delivery vehicle are adequate for targeted drug delivery applications under an external magnetic field. Additionally, an increase in the amount of chitosan was shown to exhibit a strong shielding effect over the magnetic properties of the delivery vehicle, which lead to deterioration of the amount of captured drug at the targeted area, suggesting a delicate balance between the amounts of constituents composing the drug delivery vehicle.

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Abstract Objective: To study the response of myocardial ischemia/reperfusion injury (MI/RI) in rats to simulated geomagnetic activity. Methods: In a simulated strong geomagnetic outbreak, the MI/RI rat models were radiated, and their area of myocardial infarction, hemodynamic parameters, creatine kinase (CK), lactate dehydrogenase (LDH), melatonin, and troponin I values were measured after a 24-hour intervention. Results: Our analysis indicates that the concentrations of troponin I in the geomagnetic shielding+operation group were lower than in the radiation+operation group (P<0.05), the concentrations of melatonin in the shielding+operation group and normal+operation group were higher than in the radiation + operation group (P<0.01), and the concentrations of CK in the shielding + operation group were lower than in the radiation + operation group and normal + operation group (P<0.05). Left ventricular developed pressure (LVDP) and ± dP/dtmax in the radiation+operation group were lower than in the shielding + operation group and normal+operation group (P<0.01). Left ventricular end-diastolic pressure (LEVDP) in the shielding + operation group was higher than in the normal + operation group (P<0.05). There was no significant difference in area of myocardial infarction and LDH between the shielding + operation group and the radiation + operation group. Conclusion: Our data suggest that geomagnetic activity is important in regulating myocardial reperfusion injury. The geomagnetic shielding has a protective effect on myocardial injury, and the geomagnetic radiation is a risk factor for aggravating the cardiovascular and cerebrovascular diseases.

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OBJECTIVE: To study the response of myocardial ischemia/reperfusion injury (MI/RI) in rats to simulated geomagnetic activity. METHODS: In a simulated strong geomagnetic outbreak, the MI/RI rat models were radiated, and their area of myocardial infarction, hemodynamic parameters, creatine kinase (CK), lactate dehydrogenase (LDH), melatonin, and troponin I values were measured after a 24-hour intervention. RESULTS: Our analysis indicates that the concentrations of troponin I in the geomagnetic shielding+operation group were lower than in the radiation+operation group (P<0.05), the concentrations of melatonin in the shielding+operation group and normal+operation group were higher than in the radiation + operation group (P<0.01), and the concentrations of CK in the shielding + operation group were lower than in the radiation + operation group and normal + operation group (P<0.05). Left ventricular developed pressure (LVDP) and ± dP/dtmax in the radiation+operation group were lower than in the shielding + operation group and normal+operation group (P<0.01). Left ventricular end-diastolic pressure (LEVDP) in the shielding + operation group was higher than in the normal + operation group (P<0.05). There was no significant difference in area of myocardial infarction and LDH between the shielding + operation group and the radiation + operation group. CONCLUSION: Our data suggest that geomagnetic activity is important in regulating myocardial reperfusion injury. The geomagnetic shielding has a protective effect on myocardial injury, and the geomagnetic radiation is a risk factor for aggravating the cardiovascular and cerebrovascular diseases.

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Technological advancement has increasingly exposed humans to magnetic fields (MFs). However, more insights are necessary into the potential toxicity of MF exposure as a result of genetic variations related to oxidative metabolism. Therefore, the following study has assessed an in vitro cytotoxic effect of static magnetic field (SMF) (5 mT) on cells with Val16Ala polymorphism (AA, VA, and VV) in the manganese superoxide dismutase gene. Homozygous Val16Ala-superoxide dismutase 2 (SOD2) genotypes present oxidative imbalance that is associated with risk to several chronic degenerative diseases (VV produces less efficient and AA more efficient SOD2 enzyme). Blood samples from healthy adult subject carriers with different Val16Ala-SOD2 genotypes were obtained and exposed to MF at different times (0, 1, 3, 6 h). The cytotoxic effect as well as oxidative stress was evaluated after incubation of 24 h at 37 °C. In addition, apoptosis induction has been analyzed by flow cytometry as well as Bcl-2-associated X protein (BAX), B-cell lymphoma 2 (BCL-2), and caspases 8 and 3 gene expression. SMF cytotoxic effect has been observed in AA cells at all times of exposure, whereas AV cells presented higher mortality only after 6 h of exposure at SMF. Higher apoptosis induction has been observed in AA cells when compared to VV and AV cells. These results suggest a toxicogenetic SMF effect related to an imbalance in SOD2 activity.

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Introducción: la intensidad registrada del campo electromagnético de frecuencia extremadamente baja proveniente del uso de la energía eléctrica en los ambientes laborales y comunales, supera varias veces los valores del fondo natural y se espera que se incrementen en los próximos años. El acercamiento a los CEM y el conocimiento de lo controvertido del tema, motivó la realización de este trabajo. Objetivo: mostrar la influencia de los mismos en el cuerpo humano y sus posibles implicaciones a la salud. Métodos: se realizó una revisión temática sobre este tema en revistas especializadas en salud ambiental, publicadas de 1988-1997, entre las que se encuentran: Occupational and Medicine, Scandinavian Journal of Work, Environmental and Health. Se exploraron bases de datos internacionales, otras fuentes y recursos de información. Resultados: del total de publicaciones referenciadas, solo en 4 no se relaciona la exposición a campo electromagnético con la aparición de afecciones a la salud humana; pero la gran mayoría (55 documentos) si las consideran de una u otra forma; 6 hacen referencias a que los campo electromagnético producen de alguna manera cambios a nivel biológico y fisiológico en humanos, y 49, los asocian a la ocurrencia de enfermedades. Conclusiones: es indudable que el desarrollo tecno productivo no ha sido inocente con la salud de los seres humanos. Es una necesidad actual el determinar, cuantificar y evaluar el riesgo en aras de precisar su relación con la salud humana, lo que permitirá tomar medidas en función de la protección y seguridad en el futuro(AU)

Introduction: recorded intensity of the extremely low frequency electromagnetic field (EMF) from the use of electricity at work and in community settings, exceeds several times the natural background values and is expected to increase in the coming years. The approach to the EMF and knowledge of the controversial issue prompted us to prepare this paper. Objective: to show the influence of the electromagnetic fields on the human body and its possible implications for health. Methods: occupational and Medicine, Scandinavian Journal of Work, Environmental and Health were among the specialized journals on environmental health published from 1988-1997 and used to make a literature review on this topic. International databases, sources and other information resources were explored. Results: of the total number of publications, only 4 did not relate exposure to electromagnetic field with onset of human health problems; but the vast majority (55 documents) did so in one way or another. Six made reference to the electromagnetic field causing somehow biological and physiological changes in humans whereas 49 associated it with the occurrence of diseases. Conclusions: there is no doubt that the productive and technical development has not been unrelated to human health. Therefore, it is required to determine, quantify and assess the risk in order to clarify its relation to human health, which will allow taking actions towards protection and safety in the future(AU)

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Introducción: la intensidad registrada del campo electromagnético de frecuencia extremadamente baja proveniente del uso de la energía eléctrica en los ambientes laborales y comunales, supera varias veces los valores del fondo natural y se espera que se incrementen en los próximos años. El acercamiento a los CEM y el conocimiento de lo controvertido del tema, motivó la realización de este trabajo. Objetivo: mostrar la influencia de los mismos en el cuerpo humano y sus posibles implicaciones a la salud. Métodos: se realizó una revisión temática sobre este tema en revistas especializadas en salud ambiental, publicadas de 1988-1997, entre las que se encuentran: Occupational and Medicine, Scandinavian Journal of Work, Environmental and Health. Se exploraron bases de datos internacionales, otras fuentes y recursos de información. Resultados: del total de publicaciones referenciadas, solo en 4 no se relaciona la exposición a campo electromagnético con la aparición de afecciones a la salud humana; pero la gran mayoría (55 documentos) si las consideran de una u otra forma; 6 hacen referencias a que los campo electromagnético producen de alguna manera cambios a nivel biológico y fisiológico en humanos, y 49, los asocian a la ocurrencia de enfermedades. Conclusiones: es indudable que el desarrollo tecno productivo no ha sido inocente con la salud de los seres humanos. Es una necesidad actual el determinar, cuantificar y evaluar el riesgo en aras de precisar su relación con la salud humana, lo que permitirá tomar medidas en función de la protección y seguridad en el futuro(AU)

Introduction: recorded intensity of the extremely low frequency electromagnetic field (EMF) from the use of electricity at work and in community settings, exceeds several times the natural background values and is expected to increase in the coming years. The approach to the EMF and knowledge of the controversial issue prompted us to prepare this paper. Objective: to show the influence of the electromagnetic fields on the human body and its possible implications for health. Methods: occupational and Medicine, Scandinavian Journal of Work, Environmental and Health were among the specialized journals on environmental health published from 1988-1997 and used to make a literature review on this topic. International databases, sources and other information resources were explored. Results: of the total number of publications, only 4 did not relate exposure to electromagnetic field with onset of human health problems; but the vast majority (55 documents) did so in one way or another. Six made reference to the electromagnetic field causing somehow biological and physiological changes in humans whereas 49 associated it with the occurrence of diseases. Conclusions: there is no doubt that the productive and technical development has not been unrelated to human health. Therefore, it is required to determine, quantify and assess the risk in order to clarify its relation to human health, which will allow taking actions towards protection and safety in the future(AU)

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