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Unrevealing the impact of pulsed electric fields (PEF) on cucumber seed vigour and surface disinfection. EUROBIOTECH JOURNAL 2021. [DOI: 10.2478/ebtj-2021-0027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Abstract
Chemicals used for seed treatments help to increase the agricultural production by preventing pests and pathogens but also cause environmental and health problems. Thus, environmentally-friendly technologies need to be developed for a seed treatment that inactivates surface microflora and improves seed vigor. One such pulsed electric field (PEF) treatment applied to cucumber seeds in the range of 1.07-17.28 Joule (J) significantly enhanced a mean germination rate (MGR) by up to 9%, a normal seedling rate by 25.73%, and a resistance to 100 and 200 mM salt stresses by 96% and 91.67%, respectively, with a stronger and faster growth of roots and seedlings. PEF treatment provided 3.34 and 3.22 log-reductions in the surface microflora of total mold and yeast and total aerobic mesophilic bacteria, respectively. The electrical conductivity (EC) values of the control samples increased over time, from 4 to 24 h. Those of the PEF-treated samples after 4, 12, and 24th hours were also more affected by the measurement time not by the PEF treatment.
The joint optimization of 18 responses based on the best-fit Gaussian process model pointed to 19.78 s and 17.28 J as the optimal settings. The PEF treatment appeared to improve seed germination ability and stress resistance with the adequate inactivation of surface microflora.
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Fei Y, Jin Y, Zhao X, Wang Y, Qian J, Su L, Chen G. The Relative Permittivity Changes of EGF by 50 Hz MF Exposure Neither Affect the Interaction of EGF With EGFR Nor Its Biological Effects. Bioelectromagnetics 2020; 41:241-246. [PMID: 31951053 DOI: 10.1002/bem.22249] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2019] [Accepted: 01/04/2020] [Indexed: 11/10/2022]
Abstract
The biophysical mechanism of magnetic fields (MFs) acting on living systems is not clear. Previous research showed that, similar to epidermal growth factor (EGF), MF exposure induced EGF receptor (EGFR) clustering and activated EGFR signaling. In this study, we investigated whether MF exposure induced the changes in physical characteristics of EGF and downstream effects of EGF and EGFR interaction. The phase-interrogation surface plasmon resonance (SPR) sensing analyses showed that 50 Hz MF exposure at 4.0 mT for 1 h induced reversible relative permittivity changes of EGF solution. However, compared with sham-exposed EGF solution, the MF-exposed EGF solution did not affect the binding of EGF to EGFR, nor the cell viability and EGFR clustering in human amniotic epithelial cells (FL cells). Our data suggest that cellular EGFR clustering response to MF exposure might not be a result of changes in relative permittivity of EGF in cell culture solution. Bioelectromagnetics. © 2020 Bioelectromagnetics Society.
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Affiliation(s)
- Yue Fei
- Bioelectromagnetics Laboratory, Department of Reproductive Endocrinology of Women's Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Yumin Jin
- Bioelectromagnetics Laboratory, Department of Reproductive Endocrinology of Women's Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Xinyuan Zhao
- Bioelectromagnetics Laboratory, Department of Reproductive Endocrinology of Women's Hospital, Zhejiang University School of Medicine, Hangzhou, China.,Department of Occupational Medicine and Environmental Toxicology, School of Public Health, Nantong University, Nantong, China
| | - Yiqin Wang
- State Key Laboratory of Modern Optical Instrumentation (Zhejiang University), Centre for Optical and Electromagnetics Research, Zhejiang Provincial Key Laboratory for Sensing Technologies, JORCEP (Sino-Swedish Joint Research Center of Photonics), Zhejiang University, Hangzhou, China
| | - Jun Qian
- State Key Laboratory of Modern Optical Instrumentation (Zhejiang University), Centre for Optical and Electromagnetics Research, Zhejiang Provincial Key Laboratory for Sensing Technologies, JORCEP (Sino-Swedish Joint Research Center of Photonics), Zhejiang University, Hangzhou, China
| | - Liling Su
- Bioelectromagnetics Laboratory, Department of Reproductive Endocrinology of Women's Hospital, Zhejiang University School of Medicine, Hangzhou, China.,Department of Clinical Medicine, Jiangxi Medical College, Shangrao, China
| | - Guangdi Chen
- Bioelectromagnetics Laboratory, Department of Reproductive Endocrinology of Women's Hospital, Zhejiang University School of Medicine, Hangzhou, China
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Imani M, Kazemi S, Saviz M, Farahmand L, Sadeghi B, Faraji-Dana R. Morphological Changes Induced By Extremely Low-Frequency Electric Fields. Bioelectromagnetics 2019; 40:375-390. [PMID: 31157927 DOI: 10.1002/bem.22195] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2018] [Accepted: 04/16/2019] [Indexed: 01/27/2023]
Abstract
In this paper, morphological effects of electric fields on avian erythrocytes (nucleated red blood cells) have been studied in detail. Morphological changes include rounding and cytoplasm transparency. It has been shown that the effect is non-thermal. Careful imaging and image analyses have been carried out to show that the degree of this effect is frequency-dependent, and has a higher conversion rate at higher temperatures. Furthermore, to better understand the mechanisms behind the morphological changes, we investigated the dedifferentiation hypothesis and performed a series of tests on avian erythrocytes including fluorescence spectroscopy for hemoglobin, and tests on human umbilical cord blood, mesenchymal stem cells, and bone marrow mesenchymal stem cells including flow-cytometry analysis for expression of certain markers and calcium staining. Bioelectromagnetics. 2019;40:375-390. © 2019 Bioelectromagnetics Society.
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Affiliation(s)
- Mahdi Imani
- Department of Biomedical Engineering, Amirkabir University of Technology (Tehran Polytechnic), Tehran, Iran
| | - Sepide Kazemi
- Department of Immunotherapy and Regenerative Medicine, Breast Cancer Research Center, Motamed Cancer Institute, ACECR, Tehran, Iran
| | - Mehrdad Saviz
- Department of Biomedical Engineering, Amirkabir University of Technology (Tehran Polytechnic), Tehran, Iran
| | - Leila Farahmand
- Department of Recombinant Proteins, Breast Cancer Research Center, Motamed Cancer Institute, ACECR, Tehran, Iran
| | - Behnam Sadeghi
- Department of Immunotherapy and Regenerative Medicine, Breast Cancer Research Center, Motamed Cancer Institute, ACECR, Tehran, Iran
| | - Reza Faraji-Dana
- INSF Chair of Computational Electromagnetics and Bio-electromagnetics, School of Electrical and Computer Engineering, University of Tehran, Tehran, Iran
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Torres L, Guevara B, Cruz V, Valdivia M. Myrciaria dubia "camu camu" flour as a magnetoprotector in male mouse infertility. Bioelectromagnetics 2019; 40:91-103. [PMID: 30830977 DOI: 10.1002/bem.22174] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2018] [Accepted: 01/24/2019] [Indexed: 11/06/2022]
Abstract
Possible adverse effects of extremely low frequency magnetic fields (ELF-MF) are linked to a decrease of antioxidant defenses and the production of free radicals. The increase of free radicals affects the mitochondrial functionality inducing apoptosis, which affects the phosphorylation and generation of key ATP in fertilization. Myrciaria dubia, known as "camu camu," is a fruit with high levels of ascorbic acid, which exerts an important antioxidant function in the prevention of premature cell damage. In this study, the effect of Myrciaria dubia flour on oxidative damage produced by ELF-MF (610 μT) was evaluated by detecting the activity of endogenous mitochondrial oxidoreductase enzymes in a complete sperm cycle of mice. We found that the MF caused a significant (P < 0.05) decrease in sperm quality, whereas the groups supplied with Myrciaria dubia flour (50 and 75 mg/kg of body mass) in ELF-MF exposure showed a significant recovery (P < 0.05) in parameters of viability, percentage of plasma membrane integrity and mitochondrial activity, and index of epidymal sperm. This suggests that Myrciaria dubia flour would have an antioxidant activity that counteracts the damaging effects of ELF-MF in spermatogenesis and could be used as a natural ELF-MF protector. Bioelectromagnetics. 40:91-103, 2019. © 2019 Bioelectromagnetics Society.
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Affiliation(s)
- Lizeth Torres
- Zoology Department, Universidad Nacional Mayor de San Marcos, Lima, Perú
| | - Bladimir Guevara
- Telecomunications Engineering Department, Universidad Nacional Mayor de San Marcos, Lima, Perú
| | - Víctor Cruz
- Telecomunications Engineering Department, Universidad Nacional Mayor de San Marcos, Lima, Perú
| | - Martha Valdivia
- Zoology Department, Universidad Nacional Mayor de San Marcos, Lima, Perú
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Erdem O, Akay C, Cevher SC, Canseven AG, Aydın A, Seyhan N. Effects of Intermittent and Continuous Magnetic Fields on Trace Element Levels in Guinea Pigs. Biol Trace Elem Res 2018; 181:265-271. [PMID: 28534099 DOI: 10.1007/s12011-017-1053-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/11/2017] [Accepted: 05/11/2017] [Indexed: 10/19/2022]
Abstract
Electromagnetic fields (EMFs) can affect living cells due to biochemical changes, followed by changes in levels of trace elements in serum and different organs. This study focuses on the effect of whole body exposure to EMF, presented everywhere in our environment, and on the levels of trace elements in serum, femur, brain, kidney, and liver tissues. The analyses performed on 29 guinea pigs were divided into five groups. Guinea pigs were exposed to a magnetic field of 50 Hz of 1.5 mT. Groups A and B were exposed to the magnetic field for a period of 4 h/day continuously (4 h/day) for 4 and 7 days, respectively. Groups C and D were exposed to the magnetic field for a period of 4 h/day intermittently for 4 and 7 days, respectively. Group E animals were enrolled as control. Copper (Cu), zinc (Zn), calcium (Ca), and magnesium (Mg) levels were determined by atomic absorption spectroscopy in serum, femur, brain, kidney, and liver tissues in all guinea pigs. When compared to the control groups, the changes in the levels of Cu in serum samples, femur, and kidney tissues of the treated groups were statistically significant. The same was also true for the levels of Mg in the brain, kidney, and lung tissues. Our results suggest that in vivo continuous and intermittent exposure to EMF may cause disturbances in homeostasis of bioelements. These effects could be important risk factors for toxic effects of EMF, especially in relation to deterioration of bioelements.
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Affiliation(s)
- Onur Erdem
- Department of Pharmaceutical Toxicology, University of Health Sciences, Ankara, Turkey.
| | - Cemal Akay
- Department of Pharmaceutical Toxicology, Gulhane Military Medical Academy, Ankara, Turkey
| | - Sule Coşkun Cevher
- Department of Biology, Faculty of Science and Literature, Gazi University, Ankara, Turkey
| | - Ayse Gulnihal Canseven
- Department of Biophysics, Faculty of Medicine and Gazi Non-Ionizing Radiation Protection Center, Gazi University, Ankara, Turkey
| | - Ahmet Aydın
- Department of Pharmaceutical Toxicology, Faculty of Pharmacy, Yeditepe University, Istanbul, Turkey
| | - Nesrin Seyhan
- Department of Biophysics, Faculty of Medicine and Gazi Non-Ionizing Radiation Protection Center, Gazi University, Ankara, Turkey
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Wang Z, Wang L, Zheng S, Ding Z, Liu H, Jin W, Pan Y, Chen Z, Fei Y, Chen G, Xu Z, Yu Y. Effects of electromagnetic fields on serum lipids in workers of a power plant. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2016; 23:2495-2504. [PMID: 26423285 DOI: 10.1007/s11356-015-5500-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2015] [Accepted: 09/23/2015] [Indexed: 06/05/2023]
Abstract
This study aimed to evaluate the effects of electromagnetic fields (EMF) exposure on levels of serum lipids in workers of an electric power plant. A cross-sectional study was carried out in an electric power plant in Zhejiang province, China, from August to September 2011. All participants were divided into two groups with high occupational EMF exposure and low occupational EMF exposure. The occupational EMF exposure included radiofrequency EMF and extremely low-frequency EMF. Occupational EMF exposure was associated with an increased level of low-density lipoprotein cholesterol (LDL-c; β = 0.17 mmol/L, P = 0.022). High EMF exposure group with longer employment duration, longer daily EMF exposure duration, and more mobile phone or electric fee per month had significantly higher levels of total cholesterol, LDL-c, or triglyceride than the corresponding reference group. However, significantly decreased level of high-density lipoprotein cholesterol was only observed in high EMF exposure group with more mobile phone fee per month. Similar results were also found in 544 participants with available data of serum lipids in 2010. The findings showed that chronic EMF exposure was associated with the change of serum lipid levels. EMF exposure might modulate the process of lipid metabolism.
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Affiliation(s)
- Zhaopin Wang
- Department of Epidemiology & Health Statistics, School of Public Health, Faculty of Medicine, Zhejiang University, 866 Yu-Hang-Tang Road, Xihu District, Hangzhou, 310058, Zhejiang, China
- Chronic Disease Research Institute, School of Public Health, Faculty of Medicine, Zhejiang University, Hangzhou, Zhejiang, China
| | - Lijuan Wang
- Department of Epidemiology & Health Statistics, School of Public Health, Faculty of Medicine, Zhejiang University, 866 Yu-Hang-Tang Road, Xihu District, Hangzhou, 310058, Zhejiang, China
- Chronic Disease Research Institute, School of Public Health, Faculty of Medicine, Zhejiang University, Hangzhou, Zhejiang, China
| | - Shuangshuang Zheng
- Department of Epidemiology & Health Statistics, School of Public Health, Faculty of Medicine, Zhejiang University, 866 Yu-Hang-Tang Road, Xihu District, Hangzhou, 310058, Zhejiang, China
- Chronic Disease Research Institute, School of Public Health, Faculty of Medicine, Zhejiang University, Hangzhou, Zhejiang, China
| | - Zheyuan Ding
- Department of Epidemiology & Health Statistics, School of Public Health, Faculty of Medicine, Zhejiang University, 866 Yu-Hang-Tang Road, Xihu District, Hangzhou, 310058, Zhejiang, China
- Chronic Disease Research Institute, School of Public Health, Faculty of Medicine, Zhejiang University, Hangzhou, Zhejiang, China
| | - Hui Liu
- Department of Epidemiology & Health Statistics, School of Public Health, Faculty of Medicine, Zhejiang University, 866 Yu-Hang-Tang Road, Xihu District, Hangzhou, 310058, Zhejiang, China
- Chronic Disease Research Institute, School of Public Health, Faculty of Medicine, Zhejiang University, Hangzhou, Zhejiang, China
| | - Wen Jin
- Department of Epidemiology & Health Statistics, School of Public Health, Faculty of Medicine, Zhejiang University, 866 Yu-Hang-Tang Road, Xihu District, Hangzhou, 310058, Zhejiang, China
- Chronic Disease Research Institute, School of Public Health, Faculty of Medicine, Zhejiang University, Hangzhou, Zhejiang, China
| | - Yifeng Pan
- Department of Epidemiology & Health Statistics, School of Public Health, Faculty of Medicine, Zhejiang University, 866 Yu-Hang-Tang Road, Xihu District, Hangzhou, 310058, Zhejiang, China
- Chronic Disease Research Institute, School of Public Health, Faculty of Medicine, Zhejiang University, Hangzhou, Zhejiang, China
| | - Zexin Chen
- Department of Epidemiology & Health Statistics, School of Public Health, Faculty of Medicine, Zhejiang University, 866 Yu-Hang-Tang Road, Xihu District, Hangzhou, 310058, Zhejiang, China
- Chronic Disease Research Institute, School of Public Health, Faculty of Medicine, Zhejiang University, Hangzhou, Zhejiang, China
| | - Ying Fei
- Department of Epidemiology & Health Statistics, School of Public Health, Faculty of Medicine, Zhejiang University, 866 Yu-Hang-Tang Road, Xihu District, Hangzhou, 310058, Zhejiang, China
- Chronic Disease Research Institute, School of Public Health, Faculty of Medicine, Zhejiang University, Hangzhou, Zhejiang, China
| | - Guangdi Chen
- Bioelectromagnetics Laboratory, Faculty of Medicine, Zhejiang University, Hangzhou, Zhejiang, China
| | - Zhengping Xu
- Bioelectromagnetics Laboratory, Faculty of Medicine, Zhejiang University, Hangzhou, Zhejiang, China
| | - Yunxian Yu
- Department of Epidemiology & Health Statistics, School of Public Health, Faculty of Medicine, Zhejiang University, 866 Yu-Hang-Tang Road, Xihu District, Hangzhou, 310058, Zhejiang, China.
- Chronic Disease Research Institute, School of Public Health, Faculty of Medicine, Zhejiang University, Hangzhou, Zhejiang, China.
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Elferchichi M, Mercier J, Ammari M, Belguith H, Abdelmelek H, Sakly M, Lambert K. Subacute static magnetic field exposure in rat induces a pseudoanemia status with increase in MCT4 and Glut4 proteins in glycolytic muscle. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2016; 23:1265-1273. [PMID: 26358208 DOI: 10.1007/s11356-015-5336-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2015] [Accepted: 08/28/2015] [Indexed: 06/05/2023]
Abstract
The purpose of this study was to investigate the effect of subacute exposure to static magnetic fields (SMF) on hematological and muscle biochemical parameters in rats. Male Wistar rats, daily exposed to SMF, were exposed to SMF (128 mT, 1 h/day) during 15 consecutive days. SMF-exposed rats showed a significant decrease in red blood cell (RBC) count, hemoglobin (Hb), and hematocrit (Ht) values compared to sham-exposed rats (p < 0.05). Concomitant decreases of plasma iron level against increase in transferrin amount were also observed after SMF exposure (p < 0.0.05). In postprandial condition, SMF-exposed rats presented higher plasma lactate (p < 0.01). Additionally, SMF exposure increased monocarboxylate transporters (MCT4) and glucose transporter 4 (Glut4)'s contents only in glycolytic muscle (p < 0.05). SMF exposure induced alteration of hematological parameters; importantly, we noticed a pseudoanemia status, which seems to affect tissue oxygen delivery. Additionally, SMF exposure seems to favor the extrusion of lactate from the cell to the blood compartment. Given that, these arguments advocate for an adaptive response to a hypoxia status following SMF exposure.
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Affiliation(s)
- Miryam Elferchichi
- Laboratoire de Physiologie Intégrée, Faculté des Sciences de Bizerte, Université de Carthage, Jarzouna, 7021, Tunisia.
- PHYMEDEXP, INSERM U1046, CNRS UMR 9214, Université de Montpellier, Montpellier, France.
| | - Jacques Mercier
- PHYMEDEXP, INSERM U1046, CNRS UMR 9214, Université de Montpellier, Montpellier, France
| | - Mohamed Ammari
- Laboratoire de Physiologie Intégrée, Faculté des Sciences de Bizerte, Université de Carthage, Jarzouna, 7021, Tunisia
| | - Hatem Belguith
- Laboratoire de Physiologie Intégrée, Faculté des Sciences de Bizerte, Université de Carthage, Jarzouna, 7021, Tunisia
| | - Hafedh Abdelmelek
- Laboratoire de Physiologie Intégrée, Faculté des Sciences de Bizerte, Université de Carthage, Jarzouna, 7021, Tunisia
| | - Mohsen Sakly
- Laboratoire de Physiologie Intégrée, Faculté des Sciences de Bizerte, Université de Carthage, Jarzouna, 7021, Tunisia
| | - Karen Lambert
- PHYMEDEXP, INSERM U1046, CNRS UMR 9214, Université de Montpellier, Montpellier, France
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Dimitrijević D, Savić T, Anđelković M, Prolić Z, Janać B. Extremely low frequency magnetic field (50 Hz, 0.5 mT) modifies fitness components and locomotor activity ofDrosophila subobscura. Int J Radiat Biol 2014; 90:337-43. [DOI: 10.3109/09553002.2014.888105] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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Deng Y, Zhang Y, Jia S, Liu J, Liu Y, Xu W, Liu L. Effects of aluminum and extremely low frequency electromagnetic radiation on oxidative stress and memory in brain of mice. Biol Trace Elem Res 2013; 156:243-52. [PMID: 24158621 DOI: 10.1007/s12011-013-9847-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/27/2013] [Accepted: 10/11/2013] [Indexed: 12/25/2022]
Abstract
This study was aimed to investigate the effect of aluminum and extremely low-frequency magnetic fields (ELF-MF) on oxidative stress and memory of SPF Kunming mice. Sixty male SPF Kunming mice were divided randomly into four groups: control group, ELF-MF group (2 mT, 4 h/day), load aluminum group (200 mg aluminum/kg, 0.1 ml/10 g), and ELF-MF + aluminum group (2 mT, 4 h/day, 200 mg aluminum/kg). After 8 weeks of treatment, the mice of three experiment groups (ELF-MF group, load aluminum group, and ELF-MF + aluminum group) exhibited firstly the learning memory impairment, appearing that the escaping latency to the platform was prolonged and percentage in the platform quadrant was reduced in the Morris water maze (MWM) task. Secondly are the pathologic abnormalities including neuronal cell loss and overexpression of phosphorylated tau protein in the hippocampus and cerebral cortex. On the other hand, the markers of oxidative stress were determined in mice brain and serum. The results showed a statistically significant decrease in superoxide dismutase activity and increase in the levels of malondialdehyde in the ELF-MF group (P < 0.05 or P < 0.01), load aluminum group (P < 0.01), and ELF-MF + aluminum group (P < 0.01). However, the treatment with ELF-MF + aluminum induced no more damage than ELF-MF and aluminum did, respectively. In conclusion, both aluminum and ELF-MF could impact on learning memory and pro-oxidative function in Kunming mice. However, there was no evidence of any association between ELF-MF exposure with aluminum loading.
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Affiliation(s)
- Yuanxin Deng
- Bio-wave Research Center, Department of Laboratory Medicine, Third Military Medical University, Chongqing, 400038, China
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Ding C, Luo L. Measurement of entropy production in living cells under an alternating electric field. Cell Biol Int 2013; 37:233-8. [PMID: 23364867 DOI: 10.1002/cbin.10017] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2012] [Accepted: 10/31/2012] [Indexed: 11/07/2022]
Abstract
Entropy is a thermodynamic property toward equilibrium based on the dissipation of energy. Cells constitute such a thermodynamic system, in which entropy production is both inevitable and highly significant. Although the experimental measurement of entropy production in a cell is very difficult, a new method to accomplish this in living cells is reported herein. Through heating the sample by alternating electric fields and recording the heat flow from cells, the entropy production in two normal cell lines, MCF10A and HL-7702, and two cancerous cell lines, MDA-MB-231 and SMMC-7721, was measured and compared. The scaled electroinduced entropy production rate (SEEP) of cancer cells monotonically increases with electric field strength at 5-40 V/cm, while that of normal cells changes nonmonotonically with electric field strength, reaching a peak at 5-30 V/cm. For all cell lines, the cancerous-to-normal ratio of field-induced entropy production is clearly <1 in a large range of field strength from 5 to 25 V/cm. Therefore, this work presents an easy and effective strategy for experimentally investigating the thermodynamic properties of the cell, and gives deeper insight into the physical differences between normal and cancerous cells exposed to electric fields.
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Affiliation(s)
- Changjiang Ding
- Laboratory of Theoretical Biophysics, School of Physical Science and Technology, Inner Mongolia University, Hohhot 010021, China
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Foletti A, Grimaldi S, Lisi A, Ledda M, Liboff AR. Bioelectromagnetic medicine: the role of resonance signaling. Electromagn Biol Med 2013; 32:484-99. [PMID: 23323834 DOI: 10.3109/15368378.2012.743908] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Only recently has the critical importance of electromagnetic (EM) field interactions in biology and medicine been recognized. We review the phenomenon of resonance signaling, discussing how specific frequencies modulate cellular function to restore or maintain health. The application of EM-tuned signals represents more than merely a new tool in information medicine. It can also be viewed in the larger context of EM medicine, the all-encompassing view that elevates the EM over the biochemical. The discovery by Zhadin that ultrasmall magnetic intensities are biologically significant suggests that EM signaling is endogenous to cell regulation, and consequently that the remarkable effectiveness of EM resonance treatments reflects a fundamental aspect of biological systems. The concept that organisms contain mechanisms for generating biologically useful electric signals is not new, dating back to the nineteenth century discovery of currents of injury by Matteucci. The corresponding modern-day version is that ion cyclotron resonance magnetic field combinations help regulate biological information. The next advance in medicine will be to discern and apply those EM signaling parameters acting to promote wellness, with decreasing reliance on marginal biochemical remediation and pharmaceuticals.
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Affiliation(s)
- Alberto Foletti
- Institute of Translational Pharmacology - CNR , Rome , Italy
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Ramírez-Cadavid DA, Galindo-Muñoz AR, Zapata-Ocampo PA, Rojas-Vahos DF, Fernández-Ossa C, Atehortúa-Garcés L. Efecto de los campos eléctricos sobre la producción de biomasa micelial del hongo medicinal <i>Ganoderma lucidum</i> [(W. Curt.: Fr.) P. Karst. (Ganodermataceae)]. ACTUALIDADES BIOLÓGICAS 2012. [DOI: 10.17533/udea.acbi.331479] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Se evaluó el efecto de los campos eléctricos sobre el crecimiento del hongo Ganoderma lucidum [(W. Curt.: Fr.) P. Karst. Ganodermataceae] bajo condiciones de cultivo sumergido, con el objetivo de optimizar su producción de biomasa. Ganoderma lucidum fue expuesto a tres factores diferentes [tipo de campo eléctrico corriente alterna (AC), corriente continua (DC) y corriente pulsada (IM)]; intensidad del campo [siete intensidades de campo desde 0,0 kV cm-1] (cultivo control) hasta 3,0 kV cm-1; y periodo de estimulación [dependiendo de la fase de crecimiento del hongo, después de la inoculación día 0 (fase lag), día 3 (fase exponencial o log) y día 6 (fase estacionaria)]. Los resultados mostraron que la combinación del campo eléctrico AC, con una intensidad de 1,5 kV cm-1 y aplicado al día 3 presentaron una mejor producción de biomasa con una media de 35,6450 ± 0,6684 g l-1, mientras que la combinación de los tres factores tipo de campo eléctrico DC a una intensidad de 2,5 kV cm-1 y aplicado el día 6 presentaron una menor producción de biomasa con una media de 26,2950 ± 3,9926 g l-1. Los anteriores resultados muestran que según la combinación de los factores evaluados es posible estimular la producción de biomasa del hongo Ganoderma lucidum bajo condiciones de cultivo sumergido mediante la aplicación de campo eléctrico.
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Dymek K, Dejmek P, Panarese V, Vicente AA, Wadsö L, Finnie C, Galindo FG. Effect of pulsed electric field on the germination of barley seeds. Lebensm Wiss Technol 2012. [DOI: 10.1016/j.lwt.2011.12.019] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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14
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Effect of ELF electric field on some on biochemistry characters in the rat serum. Toxicol Ind Health 2010; 27:329-33. [DOI: 10.1177/0748233710387005] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The present study has investigated the potential effects of extremely low frequency (ELF) electric field exposure on plasma cholesterol and triglyceride levels of adult male rats. Sixty rats have been divided into three independent groups randomly, 20 of which arranged as controls (without exposure to 50 Hz electric field), 20 of which have been exposed to a 50 Hz electric field for 10 days and 20 of which have been exposed to a 50-Hz electric field for 30 days. Levels of total cholesterol and triglyceride in plasma samples have been measured. Total cholesterol concentration of the plasma in group 2 with short-term exposure and group 3 with long-term exposure to 50 Hz EF (65.33 ± 15.31 mg/dL and 59.55 ± 15.01 mg/dL, respectively) has showed significant decrease when compared with control groups (70.44 ± 19.60 mg/dL). Also, plasma triglyceride showed similar changes (control: 84.44 ± 16.79 mg/dL, 67.33 ± 15.63 and 51.53 ± 14.17 mg/dL in group 1 and 2, respectively). Fifty Hz electric field may decrease plasma total cholesterol and triglyceride levels in rodents significantly, especially with long-term exposure.
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Kula B, Sobczak A, Kuśka R. EFFECTS OF STATIC AND ELF MAGNETIC FIELDS ON FREE-RADICAL PROCESSES IN RAT LIVER AND KIDNEY. ACTA ACUST UNITED AC 2009. [DOI: 10.1081/jbc-100100300] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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16
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Li JKJ, Lin JCA, Liu HC, Chang WHS. Cytokine Release from Osteoblasts in Response to Different Intensities of Pulsed Electromagnetic Field Stimulation. Electromagn Biol Med 2009; 26:153-65. [PMID: 17886003 DOI: 10.1080/15368370701572837] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
We use an in-vitro osteoblast cell culture model to investigate the effects of low-frequency (7.5 Hz) pulsed electromagnetic field (PEMF) stimulation on osteoblast population, cytokines (prostaglandin E(2) (PGE(2)), transforming growth factor beta1(TGFbeta1), and alkaline phosphatase (ALP) activity to find the optimal intensity of PEMF for osteoblast growth. The results demonstrate that PEMF can stimulate osteoblast growth, release of TGFbeta1, and, in addition, an increase of ALP activity. The synthesis and release of PGE(2) in the culture medium are reduced with increasing numbers of cells. Higher intensity does not necessarily mean increased osteoblast growth, and the most efficient intensity is about 2 mV/cm in this case. Although the lower intensities of the PEMF are yet to be determined, the results of this study can shed light on the mechanisms of PEMF stimulation on non union fracture therapy and osteoporosis prevention in the future.
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Affiliation(s)
- Jimmy Kuan-Jung Li
- Bone Tissue Engineering Research Lab, Center for Nano Bioengineering, Chung Yuan Christian University, Chung Li, Taiwan, Republic of China
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Li J, Chang WH, Jan HW, Ruaan RC, Liu HC, Sun J. Optimum Parameters of Specific 7.5 Hz Single Pulsed Electromagnetic Field Stimulation on Osteoblast Growth. Electromagn Biol Med 2009. [DOI: 10.1081/jbc-120024619] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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18
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Erdal N, Gürgül S, Tamer L, Ayaz L. Effects of long-term exposure of extremely low frequency magnetic field on oxidative/nitrosative stress in rat liver. JOURNAL OF RADIATION RESEARCH 2008; 49:181-187. [PMID: 18367817 DOI: 10.1269/jrr.07070] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Thirty-two adult Wistar-Albino female and male rats were used to investigate the long-term (45 days) effects of extremely low frequency magnetic field (ELF-MF; 50Hz, 1mT, 4h/day) exposure on oxidative/nitrosative stress in liver tissues of rats. The rats were divided randomly into four groups: female control (FC; n = 8) and MF-exposed female rats (F-MF; n = 8); male control (MC; n = 8) and MF-exposed male rats (M-MF; n = 8). Liver tissue from each animal was harvested and utilized for malondialdehyde (MDA) and 3-nitrotyrosine (3-NT) detection. MDA levels were measured by MDA-TBA method, while the 3-NT levels were determined by the HPLC-UV system. There were no significant differences between the MDA levels of the control (FC; MC) and MF-exposed (F-MF; M-MF) rats (P > 0.05). In the F-MF rats, 3-NT levels were significantly increased when compared to those of the FC rats (P < 0.05). There were no significant differences between the 3-NT levels of the MC and M-MF rats. In conclusion, our study suggests that the long-term ELF-MF exposure may enhance the oxidative/nitrosative stress in liver tissue of the female rats and could have a deteriorative effect on cellular proteins rather than lipids by enhancing 3-NT formation.
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Affiliation(s)
- Nurten Erdal
- Department of Biophysics, Faculty of Medicine, Mersin University, Turkey.
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Kula B, Sobczak A, Grabowska‐Bochenek R, Piskorska D. Effect of Electromagnetic Field on Serum Biochemical Parameters in Steelworkers. J Occup Health 2006. [DOI: 10.1539/joh.41.177] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Affiliation(s)
- Bogusław Kula
- Department of Biochemistry and ChemistryMedical University of SilesiaKatowicePoland
| | - Andrzej Sobczak
- Department of Biochemistry and ChemistryMedical University of SilesiaKatowicePoland
| | | | - Danuta Piskorska
- Department of Biochemistry and ChemistryMedical University of SilesiaKatowicePoland
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Jelenković A, Janać B, Pesić V, Jovanović DM, Vasiljević I, Prolić Z. Effects of extremely low-frequency magnetic field in the brain of rats. Brain Res Bull 2005; 68:355-60. [PMID: 16377443 DOI: 10.1016/j.brainresbull.2005.09.011] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2005] [Revised: 09/19/2005] [Accepted: 09/22/2005] [Indexed: 11/16/2022]
Abstract
An extremely low-frequency magnetic field (50 Hz, 0.5 mT) was used to investigate its possible effect on the brain of adult male Wistar rats following a 7-day exposure. The control rats were sham-exposed. Superoxide dismutase activities and production of superoxide radicals, lipid peroxidation, and nitric oxide were examined in the frontal cortex, striatum, basal forebrain, hippocampus, brainstem, and cerebellum. Significantly increased superoxide radical contents were registered in all the structures examined. Production of nitric oxide, which can oppose superoxide radical activities, was significantly increased in some structures: the frontal cortex, basal forebrain, hippocampus, and brainstem. Augmentation of lipid peroxydation was also observed, with significance only in the basal forebrain and frontal cortex, in spite of the significantly increased superoxide dismutase activities and nitric oxide production in the basal forebrain, and increased production of nitric oxide in the frontal cortex. The results obtained indicate that a 7-day exposure to extremely low-frequency magnetic field can be harmful to the brain, especially to the basal forebrain and frontal cortex due to development of lipid peroxidation. Also, high production of superoxide anion in all regions may compromise nitric oxide signaling processes, due to nitric oxide consumption in the reaction with the superoxide radical.
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Affiliation(s)
- A Jelenković
- Institute for Biological Research Sinisa Stanković, Bulevar Despota Stefana 142, 11000 Beograd, Serbia and Montenegro.
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Sobczak A, Kula B, Danch A. Effects of Electromagnetic Field on Free‐Radical Processes in Steelworkers. Part II: Magnetic Field Influence on Vitamin A, E and Selenium Concentrations in Plasma. J Occup Health 2002. [DOI: 10.1539/joh.44.230] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Affiliation(s)
- Andrzej Sobczak
- Department of General and Analytical ChemistrySilesian School of Medicine
| | - Bogusław Kula
- Department of Experimental and Clinical BiochemistrySilesian School of Medicine40‐752 KatowicePoland
| | - Alojzy Danch
- Department of Experimental and Clinical BiochemistrySilesian School of Medicine40‐752 KatowicePoland
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Wang X, Zhou A, Liu M, Yu H, Pang L, Zhu M, Wang L, Berg H. Effects of ELF capacitively coupled weak electric fields on metabolism of 6B1 cells. BIOELECTROCHEMISTRY AND BIOENERGETICS (LAUSANNE, SWITZERLAND) 1999; 48:369-73. [PMID: 10379556 DOI: 10.1016/s0302-4598(99)00024-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
In this study, we adopted several methods of MTT colorimetry, DAPI fluorimetry and ELISA to study the effects of extremely low frequency (ELF) capacitively coupled electric fields (EFs) on the metabolism of 6B1 cells. The result shows that 50 mV cm(-1) ELF EF (10-100 Hz) has no significant effect on proliferation, DNA synthesis and activity of succinate dehydrogenase of 6B1 cells, indicating that the effect of ELF (10-100 Hz) EF on the metabolism of 6B1 cells is not obvious. However, 50 mV cm(-1), 50 Hz EF significantly promotes the HBs-Ab (Hepatitis B surface antibody) secretion of 6B1 cells, implying that under this situation, EF has some distinctive effect on the outerface of 6B1 cell membrane.
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Affiliation(s)
- X Wang
- Department of Biophysical Science and Technology, Nankai University, Tianjin, China
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23
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Tang Q, Chen G, Zhao N. Effects of ELF electric field on proliferation of mouse osteoblastic cells. ACTA ACUST UNITED AC 1998. [DOI: 10.1016/s0302-4598(98)00205-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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24
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Effects of the weak alternating electric field on Na+ concentration inside human red blood cells. ACTA ACUST UNITED AC 1998. [DOI: 10.1016/s0302-4598(98)00065-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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25
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Cogalniceanu G, Radu M, Fologea D, Moisoi N, Aurelia Brezeanu. Stimulation of tobacco shoot regeneration by alternating weak electric field. ACTA ACUST UNITED AC 1998. [DOI: 10.1016/s0302-4598(97)00074-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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26
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Santoro N, Lisi A, Pozzi D, Pasquali E, Serafino A, Grimaldi S. Effect of extremely low frequency (ELF) magnetic field exposure on morphological and biophysical properties of human lymphoid cell line (Raji). BIOCHIMICA ET BIOPHYSICA ACTA 1997; 1357:281-90. [PMID: 9268052 DOI: 10.1016/s0167-4889(97)00032-3] [Citation(s) in RCA: 86] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Human B lymphoid cells (Raji) were exposed for 72 h to a 50 Hz sinusoidal magnetic field at a density of 2 milliTesla (rms). The results of exposure showed a decrease in membrane fluidity as detected by Laurdan emission spectroscopy and DPH fluorescence polarization. Field exposure also resulted in a reorganization of cytoskeletal components. Scanning electron microscopy (SEM) revealed a loss of microvilli in the exposed cells. This change in plasma membrane morphology was accompanied by a different actin distribution, as detected by phalloidin fluorescence. We also present evidence that EMF exposure of Raji cells can interfere with protein phosphorylation. Our observations confirm the hypothesis that electric and magnetic fields may modify the plasma membrane structure and interfere with the initiation of the signal cascade pathways.
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Affiliation(s)
- N Santoro
- Istituto di Medicina Sperimentale, CNR, Rome, Italy
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Cai G, Liu J, chen G, Zhao N. Ca2+ flux as a response of peritoneal exudative macrophages to weak alternating electric fields. ACTA ACUST UNITED AC 1996. [DOI: 10.1016/0302-4598(95)05043-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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28
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Jerčinović A, Hinsenkamp M, Scarceriaux B, Willaert F, de Graef C, Heenen M, Goldshmidt D. Effects of direct constant current (DC) on keratinocytes in vitro. ACTA ACUST UNITED AC 1996. [DOI: 10.1016/0302-4598(95)01900-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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29
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Jurášková V, Vetterl V, Chramosta O. Effect of cadmium and 50 Hz electric and magnetic fields on bone marrow and tumour cells. ACTA ACUST UNITED AC 1996. [DOI: 10.1016/0302-4598(95)01816-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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30
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A study of magnetic field effects on fibroblast cultures part 3. The evaluation of the effects of static and extremely low frequency (ELF) magnetic fields on glycosaminoglycan metabolism in fibroblasts, cell coats and culture medium. ACTA ACUST UNITED AC 1996. [DOI: 10.1016/0302-4598(96)89536-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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31
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Gamaley I, Augsten K, Berg H. Electrostimulation of macrophage NADPH oxidase by modulated high-frequency electromagnetic fields. ACTA ACUST UNITED AC 1995. [DOI: 10.1016/0302-4598(95)01836-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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32
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33
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Berg H. Possibilities and problems of low frequency weak electromagnetic fields in cell biology. ACTA ACUST UNITED AC 1995. [DOI: 10.1016/0302-4598(95)01831-x] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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34
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Goodman EM, Greenebaum B, Marron MT. Effects of electromagnetic fields on molecules and cells. INTERNATIONAL REVIEW OF CYTOLOGY 1995; 158:279-338. [PMID: 7721540 DOI: 10.1016/s0074-7696(08)62489-4] [Citation(s) in RCA: 202] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Evidence suggests that cell processes can be influenced by weak electromagnetic fields (EMFs). EMFs appear to represent a global interference or stress to which a cell can adapt without catastrophic consequences. There may be exceptions to this observation, however, such as the putative role of EMFs as promoters in the presence of a primary tumor initiator. The nature of the response suggests that the cell is viewing EMFs as it would another subtle environmental change. The age and state of the cell can profoundly affect the EMF bioresponse. There is no evidence that direct posttranscription effects occur as a result of EMF exposure. Although transcription alterations occur, no apparent disruption in routine physiological processes such as growth and division is immediately evident. What is usually observed is a transient perturbation followed by an adjustment by the normal homeostatic machinery of the cells. DNA does not appear to be significantly altered by EMF. If EMF exposure is associated with an increased risk of cancer, the paucity of genotoxic effects would support the suggestion that the fields act in tumor promotion rather than initiation. The site(s) and mechanisms of interaction remain to be elaborated. Although there are numerous studies and hypotheses that suggest the membrane represents the primary site of interaction, there are also several different studies showing that in vitro systems, including cell-free systems, are responsive to EMFs. The debate about potential hazards or therapeutic value of weak electromagnetic fields will continue until the mechanism of interaction has been clarified.
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Affiliation(s)
- E M Goodman
- Biomedical Research Institute, University of Wisconsin-Parkside, Kenosha 53141, USA
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