1
|
Rabbani M, Rahman E, Powner MB, Triantis IF. Making Sense of Electrical Stimulation: A Meta-analysis for Wound Healing. Ann Biomed Eng 2024; 52:153-177. [PMID: 37743460 PMCID: PMC10808217 DOI: 10.1007/s10439-023-03371-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2023] [Accepted: 09/11/2023] [Indexed: 09/26/2023]
Abstract
Electrical stimulation as a mode of external enhancement factor in wound healing has been explored widely. It has proven to have multidimensional effects in wound healing including antibacterial, galvanotaxis, growth factor secretion, proliferation, transdifferentiation, angiogenesis, etc. Despite such vast exploration, this modality has not yet been established as an accepted method for treatment. This article reviews and analyzes the approaches of using electrical stimulation to modulate wound healing and discusses the incoherence in approaches towards reporting the effect of stimulation on the healing process. The analysis starts by discussing various processes adapted in in vitro, in vivo, and clinical practices. Later it is focused on in vitro approaches directed to various stages of wound healing. Based on the analysis, a protocol is put forward for reporting in vitro works in such a way that the outcomes of the experiment are replicable and scalable in other setups. This work proposes a ground of unification for all the in vitro approaches in a more sensible manner, which can be further explored for translating in vitro approaches to complex tissue stimulation to establish electrical stimulation as a controlled clinical method for modulating wound healing.
Collapse
Affiliation(s)
- Mamun Rabbani
- Research Centre for Biomedical Engineering, School of Science and Technology, City University of London, Northampton Square, London, ECIV 0HB, UK
| | - Enayetur Rahman
- Research Centre for Biomedical Engineering, School of Science and Technology, City University of London, Northampton Square, London, ECIV 0HB, UK
| | - Michael B Powner
- Centre for Applied Vision Research, School of Health and Psychological Sciences, City University of London, Northampton Square, London, ECIV 0HB, UK
| | - Iasonas F Triantis
- Research Centre for Biomedical Engineering, School of Science and Technology, City University of London, Northampton Square, London, ECIV 0HB, UK.
| |
Collapse
|
2
|
Şenol N, Şahin M, Şahin U. The protective role of 5-hydroxy-1,4-naphthoquinone against the harmful effects of 50 Hz electric field in rat lung tissue. Electromagn Biol Med 2023; 42:133-143. [PMID: 37811636 DOI: 10.1080/15368378.2023.2265935] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2022] [Accepted: 09/16/2023] [Indexed: 10/10/2023]
Abstract
There is strong scientific evidence that the electric field is harmful to life. Exposure to an electric field (EF) can cause lung toxicity and respiratory disorders. In addition, the electric field has been shown to cause tissue damage through inflammation and apoptosis. Juglone (JUG) is one of the powerful antioxidants with anti-apoptotic and anti-inflammatory, various pharmacological properties in the biological system. In this study, we evaluated the efficacy of JUG against the potential adverse effects of electric field on the lung. Twenty-four Wistar albino rats were randomly divided into three groups; control group (Cont), EF group, and EF exposure+JUG-treated group (EJUG). After routine histological procedures, sections stained with hematoxylin-eosin (H&E) showed significant changes in lung tissues in the EF group compared to the Cont group. Significant protective effects were observed in the building volumes and histopathology in the EJUG group. Our immunohistochemical and gene expression results increased the expression of caspase-3 and tumor necrosis factor alpha (TNF-α) in the EF group (p < 0.05). Juglon increased cytokine signal suppressor (SOCS) expression (p < 0.001). These findings were consistent with the antioxidant effect of JUG treatment. We reasoned that exposure to EF damaged rat lung tissues and administration of JUG alleviated the complications caused by 50 Hz EF.
Collapse
Affiliation(s)
- Nurgül Şenol
- Department of Nutrition and Dietetics, Faculty of Health Sciences, Süleyman Demirel University, Isparta, Türkiye
| | - Melda Şahin
- Department of Bioengineering, Institute of Science, Süleyman Demirel University, Isparta, Türkiye
| | - Uğur Şahin
- Department of Chemistry, Faculty of Art and Science, University of Süleyman Demirel, Isparta, Türkiye
- Genetic Research Unit, Innovative Technologies Application and Research Center, Süleyman Demirel University, Isparta, Türkiye
| |
Collapse
|
3
|
Modulation of Macrophage Activity by Pulsed Electromagnetic Fields in the Context of Fracture Healing. Bioengineering (Basel) 2021; 8:bioengineering8110167. [PMID: 34821733 PMCID: PMC8615107 DOI: 10.3390/bioengineering8110167] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Revised: 10/22/2021] [Accepted: 10/27/2021] [Indexed: 01/05/2023] Open
Abstract
Delayed fracture healing and fracture non-unions impose an enormous burden on individuals and society. Successful healing requires tight communication between immune cells and bone cells. Macrophages can be found in all healing phases. Due to their high plasticity and long life span, they represent good target cells for modulation. In the past, extremely low frequency pulsed electromagnet fields (ELF-PEMFs) have been shown to exert cell-specific effects depending on the field conditions. Thus, the aim was to identify the specific ELF-PEMFs able to modulate macrophage activity to indirectly promote mesenchymal stem/stromal cell (SCP-1 cells) function. After a blinded screening of 22 different ELF-PEMF, two fields (termed A and B) were further characterized as they diversely affected macrophage function. These two fields have similar fundamental frequencies (51.8 Hz and 52.3 Hz) but are emitted in different groups of pulses or rather send-pause intervals. Macrophages exposed to field A showed a pro-inflammatory function, represented by increased levels of phospho-Stat1 and CD86, the accumulation of ROS, and increased secretion of pro-inflammatory cytokines. In contrast, macrophages exposed to field B showed anti-inflammatory and pro-healing functions, represented by increased levels of Arginase I, increased secretion of anti-inflammatory cytokines, and growth factors are known to induce healing processes. The conditioned medium from macrophages exposed to both ELF-PEMFs favored the migration of SCP-1 cells, but the effect was stronger for field B. Furthermore, the conditioned medium from macrophages exposed to field B, but not to field A, stimulated the expression of extracellular matrix genes in SCP-1 cells, i.e., COL1A1, FN1, and BGN. In summary, our data show that specific ELF-PEMFs may affect immune cell function. Thus, knowing the specific ELF-PEMFs conditions and the underlying mechanisms bears great potential as an adjuvant treatment to modulate immune responses during pathologies, e.g., fracture healing.
Collapse
|
4
|
Sueiro-Benavides RA, Leiro-Vidal JM, Salas-Sánchez AÁ, Rodríguez-González JA, Ares-Pena FJ, López-Martín ME. Radiofrequency at 2.45 GHz increases toxicity, pro-inflammatory and pre-apoptotic activity caused by black carbon in the RAW 264.7 macrophage cell line. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 765:142681. [PMID: 33071139 DOI: 10.1016/j.scitotenv.2020.142681] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2020] [Revised: 09/15/2020] [Accepted: 09/20/2020] [Indexed: 06/11/2023]
Abstract
Environmental factors such as air pollution by particles and/or electromagnetic fields (EMFs) are studied as harmful agents for human health. We analyzed whether the combined action of EMF with fine and coarse black carbon (BC) particles induced cell damage and inflammatory response in RAW 264.7 cell line macrophages exposed to 2.45 GHz in a gigahertz transverse electromagnetic (GTEM) chamber at sub-thermal specific absorption rate (SAR) levels. Radiofrequency (RF) dramatically increased BC-induced toxicity at high doses in the first 24 h and toxicity levels remained high 72 h later for all doses. The increase in macrophage phagocytosis induced after 24 h of RF and the high nitrite levels obtained by stimulation with lipopolysaccharide (LPS) endotoxin 24 and 72 h after radiation exposure suggests a prolongation of the innate and inflammatory immune response. The increase of proinflammatory cytokines tumor necrosis factor-α, after 24 h, and of interleukin-1β and caspase-3, after 72 h, indicated activation of the pro-inflammatory response and the apoptosis pathways through the combined effect of radiation and BC. Our results indicate that the interaction of BC and RF modifies macrophage immune response, activates apoptosis, and accelerates cell toxicity, by which it can activate the induction of hypersensitivity reactions and autoimmune disorders.
Collapse
Affiliation(s)
- Rosa Ana Sueiro-Benavides
- Research Institute on Chemical and Biological Analysis, Dept. of Microbiology and Parasitology, University of Santiago de Compostela, E-15782 Santiago de Compostela, Spain.
| | - Jose Manuel Leiro-Vidal
- Research Institute on Chemical and Biological Analysis, Dept. of Microbiology and Parasitology, University of Santiago de Compostela, E-15782 Santiago de Compostela, Spain.
| | - Aarón Ángel Salas-Sánchez
- CRETUS Institute, Dept. Applied Physics, Faculty of Physics, University of Santiago de Compostela, E-15782 Santiago de Compostela, Spain; ELEDIA@UniTN - DISI - University of Trento, 38123, Trentino-Alto Adige, Italy.
| | - J Antonio Rodríguez-González
- CRETUS Institute, Dept. Applied Physics, Faculty of Physics, University of Santiago de Compostela, E-15782 Santiago de Compostela, Spain.
| | - Francisco J Ares-Pena
- CRETUS Institute, Dept. Applied Physics, Faculty of Physics, University of Santiago de Compostela, E-15782 Santiago de Compostela, Spain.
| | - M Elena López-Martín
- CRETUS Institute, Dept. Morphological Sciences, Faculty of Medicine, University of Santiago de Compostela, E-15782 Santiago de Compostela, Spain.
| |
Collapse
|
5
|
Naghibzadeh M, Gholampour S, Naghibzadeh M, Sadeghian-Nodoushan F, Nikukar H. The effect of electromagnetic field on decreasing and increasing of the growth and proliferation rate of dermal fibroblast cell. Dermatol Ther 2020; 33:e13803. [PMID: 32526050 DOI: 10.1111/dth.13803] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2020] [Revised: 04/06/2020] [Accepted: 06/06/2020] [Indexed: 11/29/2022]
Abstract
Maintaining the health of dermal fibroblast cells and controlling their growth and proliferation would directly affect the health of skin tissues. The present study encompassed three control and three experimental specimens, which were different in terms of the duration of exposure to electromagnetic field (EMF) and intensity. With a decrease in intensity from 2 to 1 mT during 24, 48, and 72 h after exposing the cells to EMF, the frequency of the sample fibroblast cells increased by 60.3%, 144.9%, and 90.1%, respectively. With an increase in intensity from 3 to 4 mT during 48 and 72 h of exposure to EMF, the frequencies of the sample fibroblast cells decreased by 6.8% and 86.7%, respectively. It seems to be possible to achieve the most desirable condition to help the restoration of wounds and skin lesions through decreasing the exposure intensity from 2 to 0.5 mT and increasing EMF exposure time from 24 to 72 h simultaneously and non-invasively. The most desirable approach to improve the treatment of skin cancers non-invasively is to increase the intensity from 3 to 5 mT and to enhance EMF exposure time from 48 to 72 h.
Collapse
Affiliation(s)
- Mehran Naghibzadeh
- Department of Biomedical Engineering, North Tehran Branch, Islamic Azad University, Tehran, Iran
| | - Seifollah Gholampour
- Department of Biomedical Engineering, North Tehran Branch, Islamic Azad University, Tehran, Iran
| | - Majid Naghibzadeh
- Medical Nanotechnology and Tissue Engineering Research Center, Yazd Reproductive Sciences Institute, Shahid Sadoughi University of Medical Sciences, Yazd, Iran
| | - Fatemeh Sadeghian-Nodoushan
- Medical Nanotechnology and Tissue Engineering Research Center, Yazd Reproductive Sciences Institute, Shahid Sadoughi University of Medical Sciences, Yazd, Iran.,Department of Tissue engineering and Applied Cell Sciences, School of Advanced Technologies in Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Habib Nikukar
- Medical Nanotechnology and Tissue Engineering Research Center, Yazd Reproductive Sciences Institute, Shahid Sadoughi University of Medical Sciences, Yazd, Iran
| |
Collapse
|
6
|
Pulsed Electromagnetic Field Inhibits Synovitis via Enhancing the Efferocytosis of Macrophages. BIOMED RESEARCH INTERNATIONAL 2020; 2020:4307385. [PMID: 32596310 PMCID: PMC7273431 DOI: 10.1155/2020/4307385] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/06/2019] [Accepted: 03/06/2020] [Indexed: 01/15/2023]
Abstract
Synovitis plays an important role in the pathogenesis of arthritis, which is closely related to the joint swell and pain of patients. The purpose of this study was to investigate the anti-inflammatory effects of pulsed electromagnetic fields (PEMF) on synovitis and its underlying mechanisms. Destabilization of the medial meniscus (DMM) model and air pouch inflammation model were established to induce synovitis in C57BL/6 mice. The mice were then treated by PEMF (pulse waveform, 1.5 mT, 75 Hz, 10% duty cycle). The synovitis scores as well as the levels of IL-1β and TNF-α suggested that PEMF reduced the severity of synovitis in vivo. Moreover, the proportion of neutrophils in the synovial-like layer was decreased, while the proportion of macrophages increased after PEMF treatment. In addition, the phagocytosis of apoptotic neutrophils by macrophages (efferocytosis) was enhanced by PEMF. Furthermore, the data from western blot assay showed that the phosphorylation of P38 was inhibited by PEMF. In conclusion, our current data show that PEMF noninvasively exhibits the anti-inflammatory effect on synovitis via upregulation of the efferocytosis in macrophages, which may be involved in the phosphorylation of P38.
Collapse
|
7
|
Zhang M, Wang J, Sun Q, Zhang H, Chen P, Li Q, Wang Y, Qiao G. Immune response of mollusk Onchidium struma to extremely low-frequency electromagnetic fields (ELF-EMF, 50 Hz) exposure based on immune-related enzyme activity and De novo transcriptome analysis. FISH & SHELLFISH IMMUNOLOGY 2020; 98:574-584. [PMID: 32014586 DOI: 10.1016/j.fsi.2020.01.062] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/15/2019] [Revised: 01/07/2020] [Accepted: 01/30/2020] [Indexed: 06/10/2023]
Abstract
Along with rapid offshore and onshore wind power development in modern society, extremely low frequency electromagnetic fields (ELF-EMF) is produced extensively in the habits of aquatic organisms. However, the biological effects of ELF-EMF on aquatic organisms are almost sparse. In this study, Onchidium struma without shell was chosen to aim whether ELF-EMF can elicit immune response of mollusk based on immune-related enzyme activities and gene expression through high-throughput transcriptome sequencing. Three experimental groups, i.e. ELF-EMF unexposed control group (C), ELF-EMF (50 Hz, 100 μT) exposed E1 group, and ELF-EMF (50 Hz, 500 μT) exposed E2 group, were set, and coelomocytes were collected to analyze. The results showed that total coelomocyte and spherulocyte density in E1 group increased significantly compared to groups C and E2 (P < 0.05). There were no significant differences on amoebocyte and chromatocyte density among groups C, E1 and E2. ELF-EMF exposure could significantly increase immune-related enzyme activities in coelomic fluid of O. struma, including acidic phosphatase, alkaline phosphatase, antioxidative capacity, catalase, superoxide dismutase, and polyphenol oxidase (P < 0.05). A total of 54.32 Mb and 55.27 Mb raw reads with average length of 1520 bp were obtained from coelomocytes of O. struma in unexposed and exposed groups, respectively. There were 341 differentially expressed genes (DGEs) between unexposed and exposed groups, including 209 up-regulated and 132 down-regulated unigenes. All the DGEs were allocated to 14 Kyoto Encyclopedia of Genes and Genomes pathways, and five pathways were associated with immune response, including TLR/TNF/NOD-like receptor/MAPK/Fc epsilon RI signaling pathways. Altogether, short-term (to one week) exposure of O. struma to lower luxy density ELF-EMF (<500 μT) could elicit the immune response, and antioxidant system is recommended as indicators of immunological effects. Hopefully, this study will further provide insights into exploring biomarker for evaluation of the effect of ELF-EMF exposure on aquatic organisms regarding to field density, frequency and exposure duration, and provide good guidance for exploitation and utilization of renewable energy.
Collapse
Affiliation(s)
- Mingming Zhang
- Department of Marine Science and Technology, School of Marine and Biological Engineering, Yancheng Institute of Technology, Yancheng, 224051, Province Jiangsu, China
| | - Jiawei Wang
- Department of Marine Science and Technology, School of Marine and Biological Engineering, Yancheng Institute of Technology, Yancheng, 224051, Province Jiangsu, China
| | - Qirui Sun
- Department of Marine Science and Technology, School of Marine and Biological Engineering, Yancheng Institute of Technology, Yancheng, 224051, Province Jiangsu, China
| | - Hu Zhang
- Jiangsu Marine Fisheries Research Institute, Nantong, 226007, Province Jiangsu, China
| | - Peng Chen
- Department of Marine Science and Technology, School of Marine and Biological Engineering, Yancheng Institute of Technology, Yancheng, 224051, Province Jiangsu, China; Department of Aquaculture, School of Fisheries and Life, Dalian Ocean University, Dalian, 116023, Province Liaoning, China
| | - Qiang Li
- Department of Marine Science and Technology, School of Marine and Biological Engineering, Yancheng Institute of Technology, Yancheng, 224051, Province Jiangsu, China.
| | - Yinan Wang
- Department of Marine Science and Technology, School of Marine and Biological Engineering, Yancheng Institute of Technology, Yancheng, 224051, Province Jiangsu, China
| | - Guo Qiao
- Department of Marine Science and Technology, School of Marine and Biological Engineering, Yancheng Institute of Technology, Yancheng, 224051, Province Jiangsu, China.
| |
Collapse
|
8
|
Jang YW, Gil KC, Lee JS, Kang W, Park SY, Hwang KW. T-Cell Differentiation to T Helper 9 Phenotype is Elevated by Extremely Low-Frequency Electromagnetic Fields Via Induction of IL-2 Signaling. Bioelectromagnetics 2019; 40:588-601. [PMID: 31663626 DOI: 10.1002/bem.22219] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2018] [Accepted: 08/27/2019] [Indexed: 01/16/2023]
Abstract
Owing to the development of information technology and the electronics industry, and the increase in the use of electronic products, an increasing number of people are exposed to electromagnetic fields (EMFs) in daily life. There has been concern about the effects of EMFs on the human body. Th9 cells, which are characterized by the generation of interleukin-(IL-9), are a recently defined subset of T helper (Th) cells. In this study, we investigated the effect of extremely low-frequency (60 Hz) EMFs, such as those generated by household power sources, at 0.8 mT intensity on CD4+ T cells. The exposure of CD4+ T cells to such EMFs under Th9-polarizing conditions increased IL-9 secretion and gene expression of transcription factors that are important for Th9 development. The expression of GATA3 increased in the early stage, and the phosphorylation of STAT5 and STAT6, which regulate the expression of GATA3, increased. In addition, EMFs increased the expression of IL-2 by the T cells. In conclusion, the differentiation of CD4+ T cells to the Th9 phenotype was increased by exposure to extremely low-frequency EMFs, and this appeared to be dependent on the IL-2 signaling pathway. Furthermore, co-cultures of EMF-exposed Th9 cells and mast cells showed an increased expression of mast cell proteases, FcεR1α, and mast cell-derived inflammatory cytokines compared with co-cultures of non-EMF-exposed Th9 cells and mast cells. Our results suggest that EMFs enhance the differentiation of CD4+ T cells to the Th9 phenotype, resulting in mast cell activation and inflammation. Bioelectromagnetics. 2019;40:588-601. © 2019 Bioelectromagnetics Society.
Collapse
Affiliation(s)
- Ye Won Jang
- College of Pharmacy, Chung-Ang University, Seoul, Republic of Korea
| | - Ki Cheol Gil
- College of Pharmacy, Chung-Ang University, Seoul, Republic of Korea
| | - Ji Soo Lee
- College of Pharmacy, Chung-Ang University, Seoul, Republic of Korea
| | - WonKu Kang
- College of Pharmacy, Chung-Ang University, Seoul, Republic of Korea
| | - So-Young Park
- Laboratory of Pharmacognosy, College of Pharmacy, Dankook University, Cheonan, Republic of Korea
| | - Kwang Woo Hwang
- College of Pharmacy, Chung-Ang University, Seoul, Republic of Korea
| |
Collapse
|
9
|
Nasrabadi N, Soheili ZS, Bagheri A, Ahmadieh H, Amizadeh Y, Sahebjam F, Tabeie F, Rezaei Kanavi M. The effects of electromagnetic fields on cultured human retinal pigment epithelial cells. Bioelectromagnetics 2019; 39:585-594. [PMID: 30462846 DOI: 10.1002/bem.22154] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Accepted: 10/16/2018] [Indexed: 12/26/2022]
Abstract
A great deal of evidence has confirmed that electromagnetic fields (EMFs) can affect the central nervous system. In this study, cultured neonatal human retinal pigment epithelial (hRPE) cells were exposed to pulsed EMF of 1 mT intensity and 50 Hz frequency 8 h daily for 3 days. In addition to cell proliferation and cell death assays, immunocytochemistry for RPE65, PAX6, nestin, and cytokeratin 8/18 proteins were performed. Real-time reverse transcriptase polymerase chain reaction (RT-PCR) was performed for NES, PAX6, RPE65, and ACTA2 gene expression. Exposed hRPE cells did not demonstrate significant change in terms of cytomorphology, cell proliferation, or cell death. Protein expression of PAX6 was decreased in treated cells compared to controls and remained unchanged for RPE65, cytokeratin 8/18, and nestin. Gene expressions of NES, RPE65, and PAX6 were decreased in treated cells as compared to controls. Gene expression of ACTA2 did not significantly change. In conclusion, viability of cultivated neonatal hRPE cells did not change after short exposure to a safe dose of pulsed EMF albeit that both gene and protein expressions of retinal progenitor cell markers were reduced. Whether longer exposure durations that are being constantly produced by widely-used electronic devices may induce significant changes in these cells, needs further investigation. Bioelectromagnetics. 39:585-594, 2018. © 2018 Wiley Periodicals, Inc.
Collapse
Affiliation(s)
- Niyousha Nasrabadi
- Ocular Tissue Engineering Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | | | - Abouzar Bagheri
- Faculty of Medicine, Department of Clinical Biochemistry and Genetics, Molecular and Cell Biology Research Center, Mazandaran University of Medical Sciences, Sari, Iran
| | - Hamid Ahmadieh
- Ophthalmic Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Yashar Amizadeh
- Ophthalmic Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Farzin Sahebjam
- School of Veterinary Science, Massey University, Palmerston North, New Zealand
| | - Faraj Tabeie
- Department of Nuclear Medicine, Taleghani Hospital, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Mozhgan Rezaei Kanavi
- Ocular Tissue Engineering Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| |
Collapse
|
10
|
Simkó M, Mattsson MO. Activation of the intracellular temperature and ROS sensor membrane protein STIM1 as a mechanism underpinning biological effects of low-level low frequency magnetic fields. Med Hypotheses 2018; 122:68-72. [PMID: 30593427 DOI: 10.1016/j.mehy.2018.10.013] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2018] [Revised: 10/16/2018] [Accepted: 10/20/2018] [Indexed: 01/22/2023]
Abstract
The biological effects of low frequency magnetic fields (LF MF) at high flux densities are well known and the underlying mechanism is established. In contrast, health associated effects at lower flux densities, which can be found in the human environment, are controversial, and no accepted interaction mechanism has been presented. Here we present a hypothesis regarding the biological aspect of interaction between LF MF and cells. We suggest that the endoplasmic reticulum (ER) membrane protein STIM1, which functions as a sensor for several cellular conditions (low Ca2+ levels, temperature increase, increased levels of oxygen radicals, hypoxia), is a candidate LF MF sensor. Such a sensor function can be either direct (via local temperature increase caused by intracellularly induced electric fields), or indirect due to responses to increased reactive oxygen species (ROS) levels. Activated STIM1 leads to downstream effects by activation of signal transduction processes and changes in gene expression leading to secondary events. The nature of these changes would be dependent on both cell type and the particular physiological state the cell displays at the time of STIM1 activation. Results from testing of this hypothesis, as suggested in this paper, would greatly assist in understanding of the possible health-related effects of low-level LF MF. This would benefit both safety assessments regarding MF exposure as well as possible use of MF in medicine. A better understanding of the biological mechanisms underpinning MF exposure effects of living matter allows the targeted use of the fields in medical applications. There are several examples already in use based on empiric and not on mechanistic knowledge. Knowledge generated from our hypothesis testing makes it possible for MF based medical applications to be optimized.
Collapse
|
11
|
Wyszkowska J, Jędrzejewski T, Piotrowski J, Wojciechowska A, Stankiewicz M, Kozak W. Evaluation of the influence of in vivo exposure to extremely low-frequency magnetic fields on the plasma levels of pro-inflammatory cytokines in rats. Int J Radiat Biol 2018; 94:909-917. [DOI: 10.1080/09553002.2018.1503428] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Affiliation(s)
- Joanna Wyszkowska
- Department of Biophysics, Faculty of Biology and Environmental Protection, Nicolaus Copernicus University, Toruń, Poland
| | - Tomasz Jędrzejewski
- Department of Immunology, Faculty of Biology and Environmental Protection, Nicolaus Copernicus University, Toruń, Poland
| | - Jakub Piotrowski
- Department of Immunology, Faculty of Biology and Environmental Protection, Nicolaus Copernicus University, Toruń, Poland
| | - Anna Wojciechowska
- Chair of Geobotany and Landscape Planning, Faculty of Biology and Environmental Protection, Nicolaus Copernicus University, Toruń, Poland
| | - Maria Stankiewicz
- Department of Biophysics, Faculty of Biology and Environmental Protection, Nicolaus Copernicus University, Toruń, Poland
| | - Wieslaw Kozak
- Department of Immunology, Faculty of Biology and Environmental Protection, Nicolaus Copernicus University, Toruń, Poland
| |
Collapse
|
12
|
Comparative Analysis of Biological Effects Induced on Different Cell Types by Magnetic Fields with Magnetic Flux Densities in the Range of 1–60 mT and Frequencies up to 50 Hz. SUSTAINABILITY 2018. [DOI: 10.3390/su10082776] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Moderate static magnetic fields (SMFs) are generated from sources such as new-generation electric trams and trains, electric arc welding, and magnetic resonance imaging (MRI) devices, as well as during the industrial production of aluminium, while extremely low frequency pulsed magnetic fields (ELF-PMFs) are produced by house power installations, household appliances, and high voltages transmission lines. Moderate SMFs and ELF-PMFs with magnetic flux densities (B) in the range of 1–60 mT and frequencies (f) up to 50 Hz are common MF exposure sources for the population. Even though humans are continually exposed to these MFs, to date no definitive endpoint has been drawn about their safety. In this review, the state of knowledge about the biological effects induced by these MFs on different cell types will be addressed. In our own observation, the putative modulation of Ca2+/H+ and Na+/H+ plasma membrane antiporters of human peripheral blood lymphocytes (PBLs) was found to occur after a 24 h exposure to a 6 mT SMF, and the bystander effect observed on U937 cells cultivated for up to 6 h in the conditioned medium harvested from human PBLs previously exposed for 24 h to the same MF (secondary necrosis induction) will be also herein discussed.
Collapse
|
13
|
Dornelles EB, Goncalves BD, Schott KL, Barbisan F, Unfer TC, Glanzner WG, Machado AK, Cadona FC, Azzolin VF, Montano MAE, Griner J, da Cruz IBM. Cytotoxic effects of moderate static magnetic field exposure on human periphery blood mononuclear cells are influenced by Val16Ala-MnSOD gene polymorphism. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2017; 24:5078-5088. [PMID: 28004364 DOI: 10.1007/s11356-016-8176-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/22/2016] [Accepted: 11/28/2016] [Indexed: 06/06/2023]
Abstract
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.
Collapse
Affiliation(s)
- Eduardo B Dornelles
- Biological Science Graduate Program: Toxicological Biochemistry, Universidade Federal de Santa Maria, Av Roraima 1000, Prédio 19, Santa Maria, RS, 97105900, Brazil.
| | - Bayard D Goncalves
- Veterinary Medicine Graduate Program, Universidade Federal de Santa Maria, Santa Maria, RS, Brazil
| | - Karen Lilian Schott
- Biological Science Graduate Program: Toxicological Biochemistry, Universidade Federal de Santa Maria, Av Roraima 1000, Prédio 19, Santa Maria, RS, 97105900, Brazil
| | - Fernanda Barbisan
- Pharmacology Graduate Program, Universidade Federal de Santa Maria, Santa Maria, RS, Brazil
| | - Tais C Unfer
- Pharmacology Graduate Program, Universidade Federal de Santa Maria, Santa Maria, RS, Brazil
| | - Werner G Glanzner
- Veterinary Medicine Graduate Program, Universidade Federal de Santa Maria, Santa Maria, RS, Brazil
| | - Alencar K Machado
- Pharmacology Graduate Program, Universidade Federal de Santa Maria, Santa Maria, RS, Brazil
| | - Francine C Cadona
- Biological Science Graduate Program: Toxicological Biochemistry, Universidade Federal de Santa Maria, Av Roraima 1000, Prédio 19, Santa Maria, RS, 97105900, Brazil
| | | | - Marco Aurélio Echart Montano
- Health and Biosciences Post-Graduate Program, Universidade do Oeste de Santa Catarina, Rua Dirceu Giordani, 696, Xanxerê, 89820-000, SC, Brazil
| | - John Griner
- Biological Science Graduate Program: Toxicological Biochemistry, Universidade Federal de Santa Maria, Av Roraima 1000, Prédio 19, Santa Maria, RS, 97105900, Brazil
| | - Ivana B M da Cruz
- Biological Science Graduate Program: Toxicological Biochemistry, Universidade Federal de Santa Maria, Av Roraima 1000, Prédio 19, Santa Maria, RS, 97105900, Brazil
- Pharmacology Graduate Program, Universidade Federal de Santa Maria, Santa Maria, RS, Brazil
| |
Collapse
|
14
|
Akbarnejad Z, Eskandary H, Vergallo C, Nematollahi-Mahani SN, Dini L, Darvishzadeh-Mahani F, Ahmadi M. Effects of extremely low-frequency pulsed electromagnetic fields (ELF-PEMFs) on glioblastoma cells (U87). Electromagn Biol Med 2016; 36:238-247. [PMID: 27874284 DOI: 10.1080/15368378.2016.1251452] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
The impact of extremely low-frequency pulsed electromagnetic fields (ELF-PEMFs) at various frequencies and amplitudes was investigated on cell cycle, apoptosis and viability of the Glioblastoma Multiforme (GBM) cell line (U87), in vitro. The GBM is a malignant brain tumor with high mortality in humans and poorly responsive to the most common type of cancer treatments, such as surgery, chemotherapy and radiation therapy. U87 cells with five experimental groups (I-V) were exposed to various ELF-PEMFs for 2, 4 and 24 h, as follows: (I) no exposure, control; (II) 50 Hz 100 ± 15 G; (III) 100 Hz 100 ± 15 G; (IV) 10 Hz 50 ± 10 G; (V) 50 Hz 50 ± 10 G. The morphology properties, cell viability and gene expression of proteins involved in cell cycle regulation (Cyclin-D1 and P53) and apoptosis (Caspase-3) were investigated. After 24 h, the cell viability and Cyclin-D1 expression increased in Group II (30%, 45%), whereas they decreased in Groups III (29%, 31%) and IV (21%, 34%); P53 and Caspase-3 elevated only in Group III; and no significant difference was observed in Group V, respectively, compared with the control (p < 0.05). The data suggest that the proliferation and apoptosis of human GBM are influenced by exposure to ELF-PEMFs in different time-dependent frequencies and amplitudes. The fact that some of the ELF-PEMFs frequencies and amplitudes favor U87 cells proliferation indicates precaution for the use of medical devices related to the MFs on cancer patients. On the other hand, some other ELF-PEMFs frequencies and intensities arresting U87 cells growth could open the way to develop novel therapeutic approaches.
Collapse
Affiliation(s)
- Zeinab Akbarnejad
- a Neuroscience Research Center, Institute of Neuropharmacology , Kerman University of Medical Sciences , Kerman , Iran
| | - Hossein Eskandary
- a Neuroscience Research Center, Institute of Neuropharmacology , Kerman University of Medical Sciences , Kerman , Iran.,b Afzal Research Institute (NGO) , Kerman , Iran
| | - Cristian Vergallo
- c Department of Biological and Environmental Science and Technology (Di.S.Te.B.A.) , University of Salento , Lecce , Italy
| | | | - Luciana Dini
- c Department of Biological and Environmental Science and Technology (Di.S.Te.B.A.) , University of Salento , Lecce , Italy.,e CNR Nanotec , Lecce , Italy
| | - Fatemeh Darvishzadeh-Mahani
- a Neuroscience Research Center, Institute of Neuropharmacology , Kerman University of Medical Sciences , Kerman , Iran
| | - Meysam Ahmadi
- a Neuroscience Research Center, Institute of Neuropharmacology , Kerman University of Medical Sciences , Kerman , Iran
| |
Collapse
|
15
|
He GL, Luo Z, Shen TT, Li P, Yang J, Luo X, Chen CH, Gao P, Yang XS. Inhibition of STAT3- and MAPK-dependent PGE 2 synthesis ameliorates phagocytosis of fibrillar β-amyloid peptide (1-42) via EP2 receptor in EMF-stimulated N9 microglial cells. J Neuroinflammation 2016; 13:296. [PMID: 27871289 PMCID: PMC5117690 DOI: 10.1186/s12974-016-0762-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2016] [Accepted: 11/09/2016] [Indexed: 12/16/2022] Open
Abstract
Background Prostaglandin E2 (PGE2)-involved neuroinflammatory processes are prevalent in several neurological conditions and diseases. Amyloid burden is correlated with the activation of E-prostanoid (EP) 2 receptors by PGE2 in Alzheimer’s disease. We previously demonstrated that electromagnetic field (EMF) exposure can induce pro-inflammatory responses and the depression of phagocytosis in microglial cells, but the signaling pathways involved in phagocytosis of fibrillar β-amyloid (fAβ) in microglial cells exposed to EMF are poorly understood. Given the important role of PGE2 in neural physiopathological processes, we investigated the PGE2-related signaling mechanism in the immunomodulatory phagocytosis of EMF-stimulated N9 microglial cells (N9 cells). Methods N9 cells were exposed to EMF with or without pretreatment with the selective inhibitors of cyclooxygenase-2 (COX-2), Janus kinase 2 (JAK2), signal transducer and activator of transcription 3 (STAT3), and mitogen-activated protein kinases (MAPKs) and antagonists of PG receptors EP1-4. The production of endogenous PGE2 was quantified by enzyme immunoassays. The phagocytic ability of N9 cells was evaluated based on the fluorescence intensity of the engulfed fluorescent-labeled fibrillar β-amyloid peptide (1-42) (fAβ42) measured using a flow cytometer and a fluorescence microscope. The effects of pharmacological agents on EMF-activated microglia were investigated based on the expressions of JAK2, STAT3, p38/ERK/JNK MAPKs, COX-2, microsomal prostaglandin E synthase-1 (mPGES-1), and EP2 using real-time PCR and/or western blotting. Results EMF exposure significantly increased the production of PGE2 and decreased the phagocytosis of fluorescent-labeled fAβ42 by N9 cells. The selective inhibitors of COX-2, JAK2, STAT3, and MAPKs clearly depressed PGE2 release and ameliorated microglial phagocytosis after EMF exposure. Pharmacological agents suppressed the phosphorylation of JAK2-STAT3 and MAPKs, leading to the amelioration of the phagocytic ability of EMF-stimulated N9 cells. Antagonist studies of EP1-4 receptors showed that EMF depressed the phagocytosis of fAβ42 through the PGE2 system, which is linked to EP2 receptors. Conclusions This study indicates that EMF exposure could induce phagocytic depression via JAK2-STAT3- and MAPK-dependent PGE2-EP2 receptor signaling pathways in microglia. Therefore, pharmacological inhibition of PGE2 synthesis and EP2 receptors may be a potential therapeutic strategy to combat the neurobiological deterioration that follows EMF exposure. Electronic supplementary material The online version of this article (doi:10.1186/s12974-016-0762-9) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Gen-Lin He
- Department of Tropic Hygiene, Institute of Tropical Medicine, Third Military Medical University, 30 Gaotanyan Street, Chongqing, 400038, People's Republic of China
| | - Zhen Luo
- Department of Tropic Hygiene, Institute of Tropical Medicine, Third Military Medical University, 30 Gaotanyan Street, Chongqing, 400038, People's Republic of China
| | - Ting-Ting Shen
- Department of Tropic Hygiene, Institute of Tropical Medicine, Third Military Medical University, 30 Gaotanyan Street, Chongqing, 400038, People's Republic of China
| | - Ping Li
- Department of Tropic Hygiene, Institute of Tropical Medicine, Third Military Medical University, 30 Gaotanyan Street, Chongqing, 400038, People's Republic of China
| | - Ju Yang
- Department of Tropic Hygiene, Institute of Tropical Medicine, Third Military Medical University, 30 Gaotanyan Street, Chongqing, 400038, People's Republic of China
| | - Xue Luo
- Department of Tropic Hygiene, Institute of Tropical Medicine, Third Military Medical University, 30 Gaotanyan Street, Chongqing, 400038, People's Republic of China
| | - Chun-Hai Chen
- Key Laboratory of Medical Protection for Electromagnetic Radiation Ministry of Education, Third Military Medical University, Chongqing, 400038, People's Republic of China
| | - Peng Gao
- Key Laboratory of Medical Protection for Electromagnetic Radiation Ministry of Education, Third Military Medical University, Chongqing, 400038, People's Republic of China
| | - Xue-Sen Yang
- Department of Tropic Hygiene, Institute of Tropical Medicine, Third Military Medical University, 30 Gaotanyan Street, Chongqing, 400038, People's Republic of China.
| |
Collapse
|
16
|
Altunkaynak BZ, Altun G, Yahyazadeh A, Kaplan AA, Deniz OG, Türkmen AP, Önger ME, Kaplan S. Different methods for evaluating the effects of microwave radiation exposure on the nervous system. J Chem Neuroanat 2016; 75:62-9. [DOI: 10.1016/j.jchemneu.2015.11.004] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2015] [Revised: 11/16/2015] [Accepted: 11/16/2015] [Indexed: 01/13/2023]
|
17
|
Shekoohi-Shooli F, Mortazavi SMJ, Shojaei-Fard MB, Nematollahi S, Tayebi M. Evaluation of the Protective Role of Vitamin C on the Metabolic and Enzymatic Activities of the Liver in the Male Rats After Exposure to 2.45 GHz Of Wi-Fi Routers. J Biomed Phys Eng 2016; 6:157-164. [PMID: 27853723 PMCID: PMC5106548] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2015] [Indexed: 06/06/2023]
Abstract
BACKGROUND The use of devices emitted microwave radiation such as mobile phones, wireless fidelity (Wi-Fi) routers, etc. is increased rapidly. It has caused a great concern; the researchers should identify its effects on people's health. We evaluated the protective role of Vitamin C on the metabolic and enzymatic activities of the liver after exposure to Wi-Fi routers. MATERIAL AND METHODS 70 male Wistar rats weighing 200-250 g were randomly divided into 7 groups (10 rats in each group).The first stage one -day test: Group A (received vitamin C 250 mg/kg/day orally together with 8- hour/day Wi-Fi exposure).Group B (exposed to Wi-Fi radiation). Group C (received vitamin C). Group D or Control (was neither exposed to radiation of Wi-Fi modem nor did receive vitamin C). The second phase of experiment had done for five consecutive days. It involved Group E (received vitamin C), Group F (exposed to Wi-Fi radiation), Group G (received vitamin C together with Wi-Fi radiation). The distance between animals' restrainers was 20 cm away from the router antenna. Finally, blood samples were collected and assayed the level of hepatic enzymes including alkaline phosphatase(ALP), alanine amino transferase(ALT) aspartate amino transferase (ASL), gamma glutamyl transferase (GGT) and the concentration of Blood Glucose, Cholesterol , Triglyceride(TG),High density lipoprotein (HDL)and low density lipoprotein (LDL). RESULTS Data obtained from the One day test showed an increase in concentration of blood glucose, decrease in Triglyceride level and GGT factor (P<0.05), however no observed significant difference on the Cholesterol , HDL , LDL level and hepatic enzymes activities in compare to control group. Groups of the five-day test showed reduction in the amount of blood glucose, elevation of cholesterol level and LDL relative to control group(P<0.05). CONCLUSION WiFi exposure may exert alternations on the metabolic parameters and hepatic enzymes activities through stress oxidative and increasing of free radicals, but the use of vitamin C protects them from changing induced. Also taking optimum dose of vitamin C is essential for radioprotective effect and maintaining optimum health.
Collapse
Affiliation(s)
- F Shekoohi-Shooli
- Ionizing and Non-ionizing Radiation Protection Research Center, Shiraz University of Medical Sciences, Shiraz, Iran
| | - S M J Mortazavi
- Ionizing and Non-ionizing Radiation Protection Research Center, Shiraz University of Medical Sciences, Shiraz, Iran
| | - M B Shojaei-Fard
- Department of Physiology, Fasa University of Medical Sciences, Fasa, Iran; Ionizing and Non-ionizing Radiation Protection Research Center, Shiraz University of Medical Sciences, Shiraz, Iran
| | - S Nematollahi
- Biostatistics Department, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran
| | - M Tayebi
- Ionizing and Non-ionizing Radiation Protection Research Center, Shiraz University of Medical Sciences, Shiraz, Iran
| |
Collapse
|
18
|
Ferchichi S, Trabelsi H, Azzouz I, Hanini A, Rejeb A, Tebourbi O, Sakly M, Abdelmelek H. Evaluation of oxidative response and tissular damage in rat lungs exposed to silica-coated gold nanoparticles under static magnetic fields. Int J Nanomedicine 2016; 11:2711-9. [PMID: 27354800 PMCID: PMC4907707 DOI: 10.2147/ijn.s103140] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
The purpose of our study was the evaluation of toxicological effects of silica-coated gold nanoparticles (GNPs) and static magnetic fields (SMFs; 128 mT) exposure in rat lungs. Animals received a single injection of GNPs (1,100 µg/kg, 100 nm, intraperitoneally) and were exposed to SMFs, over 14 days (1 h/day). Results showed that GNPs treatment induced a hyperplasia of bronchus-associated lymphoid tissue. Fluorescence microscopy images showed that red fluorescence signal was detected in rat lungs after 2 weeks from the single injection of GNPs. Oxidative response study showed that GNPs exposure increased malondialdehyde level and decreased CuZn-superoxide dismutase, catalase, and glutathione peroxidase activities in rat lungs. Furthermore, the histopathological study showed that combined effects of GNPs and SMFs led to more tissular damages in rat lungs in comparison with GNPs-treated rats. Interestingly, intensity of red fluorescence signal was enhanced after exposure to SMFs indicating a higher accumulation of GNPs in rat lungs under magnetic environment. Moreover, rats coexposed to GNPs and SMFs showed an increased malondialdehyde level, a fall of CuZn-superoxide dismutase, catalase, and glutathione peroxidase activities in comparison with GNPs-treated group. Hence, SMFs exposure increased the accumulation of GNPs in rat lungs and led to more toxic effects of these nanocomplexes.
Collapse
Affiliation(s)
- Soumaya Ferchichi
- Laboratory of Integrative Physiology, Faculty Of Sciences of Bizerte, Carthage University, Carthage, Tunisia
| | - Hamdi Trabelsi
- Laboratory of Integrative Physiology, Faculty Of Sciences of Bizerte, Carthage University, Carthage, Tunisia
| | - Inès Azzouz
- Laboratory of Integrative Physiology, Faculty Of Sciences of Bizerte, Carthage University, Carthage, Tunisia
| | - Amel Hanini
- Laboratory of Vascular Pathology, Carthage University, Carthage, Tunisia
| | - Ahmed Rejeb
- Laboratory of Pathological Anatomy, National School of Veterinary Medicine of Sidi Thabet, Manouba Univeristy, Manouba, Tunisia
| | - Olfa Tebourbi
- Laboratory of Integrative Physiology, Faculty Of Sciences of Bizerte, Carthage University, Carthage, Tunisia
| | - Mohsen Sakly
- Laboratory of Integrative Physiology, Faculty Of Sciences of Bizerte, Carthage University, Carthage, Tunisia
| | - Hafedh Abdelmelek
- Laboratory of Integrative Physiology, Faculty Of Sciences of Bizerte, Carthage University, Carthage, Tunisia
| |
Collapse
|
19
|
Golbach LA, Philippi JG, Cuppen JJ, Savelkoul HF, Verburg-van Kemenade BL. Calcium signalling in human neutrophil cell lines is not affected by low-frequency electromagnetic fields. Bioelectromagnetics 2015; 36:430-43. [DOI: 10.1002/bem.21924] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2014] [Accepted: 05/11/2015] [Indexed: 12/18/2022]
Affiliation(s)
- Lieke A. Golbach
- Cell Biology and Immunology Group; Wageningen University; The Netherlands
| | - John G.M. Philippi
- Lab of Biophysics and Wageningen NMR Centre; Wageningen University; The Netherlands
| | | | | | | |
Collapse
|
20
|
Nofouzi K, Sheikhzadeh N, Mohamad-Zadeh Jassur D, Ashrafi-Helan J. Influence of extremely low frequency electromagnetic fields on growth performance, innate immune response, biochemical parameters and disease resistance in rainbow trout, Oncorhynchus mykiss. FISH PHYSIOLOGY AND BIOCHEMISTRY 2015; 41:721-731. [PMID: 25869215 DOI: 10.1007/s10695-015-0041-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2014] [Accepted: 03/09/2015] [Indexed: 06/04/2023]
Abstract
The effects of extremely low frequency electromagnetic fields on rainbow trout growth performance, innate immunity and biochemical parameters were studied. Rainbow trout (17-18 g) were exposed to electromagnetic fields (15 Hz) at 0.01, 0.1, 0.5, 5 and 50 µT, for 1 h daily over period of 60 days. Growth performance of fish improved in different treatment groups, especially at 0.1, 0.5, 5 and 50 µT. Immunological parameters, specifically hemagglutinating titer, total antiprotease and α1-antiprotease levels in treatment groups, were also enhanced. Total protein and globulin contents in the serum of fish exposed to 0.1, 0.5, 5 and 50 µT were significantly higher than those in the control group. No significant differences were found in serum enzyme activities, namely aspartate aminotransferase and alanine aminotransferase of fish in all treatment groups. Conversely, alkaline phosphatase level decreased in fish exposed to 0.01 and 50 µT electromagnetic fields. Meanwhile, electromagnetic induction at 0.1, 0.5, 5 and 50 µT enhanced fish protection against Yersinia ruckeri. These results indicated that these specific electromagnetic fields had possible effects on growth performance, nonspecific immunity and disease resistance of rainbow trout.
Collapse
Affiliation(s)
- Katayoon Nofouzi
- Department of Pathobiology, Faculty of Veterinary Medicine, University of Tabriz, Tabriz, Iran,
| | | | | | | |
Collapse
|
21
|
Effect of long-term pulsed electromagnetic field exposure on hepatic and immunologic functions of rats. Wien Klin Wochenschr 2015; 127:959-62. [PMID: 25910613 DOI: 10.1007/s00508-015-0732-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2014] [Accepted: 01/19/2015] [Indexed: 02/04/2023]
Abstract
BACKGROUND In this report, the effects of long-term pulsed electromagnetic field (PEMF) exposure on hepatic and immunologic functions were examined. METHODS Male rats were randomly divided into four groups: a control group and three experimental groups exposed to a 50-Hz PEMF at 5, 10, or 20 mT for 10 weeks. RESULTS Compared with the control group, activities of serum alanine aminotransferase and aspartate aminotransferase and concentrations of serum, liver, and spleen Metabolism of lipid peroxidation (MDA) in the 10- and 20-mT PEMF groups were significantly increased. The activities of Glutathione peroxidase (GSH-Px) and Superoxide Dismutase (SOD) in the serum, liver, and spleen and concentrations of serum immunoglobulins were significantly decreased. CONCLUSION These results demonstrate that long-term exposure to PEMF can lead to oxidative damage of the liver and spleen.
Collapse
|
22
|
Mattsson MO, Simkó M. Grouping of Experimental Conditions as an Approach to Evaluate Effects of Extremely Low-Frequency Magnetic Fields on Oxidative Response in in vitro Studies. Front Public Health 2014; 2:132. [PMID: 25229055 PMCID: PMC4151017 DOI: 10.3389/fpubh.2014.00132] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2014] [Accepted: 08/19/2014] [Indexed: 11/13/2022] Open
Abstract
A large body of literature deals with biological effects of extremely low-frequency magnetic fields (ELF MFs) studied in vitro. Despite the multitude of studies, no coherent picture has evolved regarding the plausibility of effects at low-flux densities or regarding the interaction mechanisms. Here, we propose that ELF MF exposure in vitro causes changes in oxidative status as an early response. We tested this hypothesis by scrutinizing the literature and applying a grouping approach for analyzing relevant biological properties and exposure conditions. A total of 41 scientific original publications were analyzed for this purpose. The conclusion from the work is that ELF MF (modulated or unmodulated) consistently can influence the oxidative status, at or above 1 mT, in a broad range of cell types and independent of exposure duration. A response at lower flux densities is seen in certain studies, although not consistently. Further studies with stringent protocols for sham exposure, blinding, and statistical analysis as well as appropriate positive controls are needed to establish if true dose-relationships for effects on oxidative status exist.
Collapse
Affiliation(s)
- Mats-Olof Mattsson
- Environmental Resources and Technologies, Department Health and Environment, AIT Austrian Institute of Technology, Tulln, Austria
| | - Myrtill Simkó
- Environmental Resources and Technologies, Department Health and Environment, AIT Austrian Institute of Technology, Tulln, Austria
| |
Collapse
|
23
|
D'Angelo C, Costantini E, Kamal MA, Reale M. Experimental model for ELF-EMF exposure: Concern for human health. Saudi J Biol Sci 2014; 22:75-84. [PMID: 25561888 DOI: 10.1016/j.sjbs.2014.07.006] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2014] [Revised: 07/16/2014] [Accepted: 07/17/2014] [Indexed: 11/29/2022] Open
Abstract
Low frequency (LF) electromagnetic fields (EMFs) are abundantly present in modern society and in the last 20 years the interest about the possible effect of extremely low frequency (ELF) EMFs on human health has increased progressively. Epidemiological studies, designed to verify whether EMF exposure may be a potential risk factor for health, have led to controversial results. The possible association between EMFs and an increased incidence of childhood leukemia, brain tumors or neurodegenerative diseases was not fully elucidated. On the other hand, EMFs are widely used, in neurology, psychiatry, rheumatology, orthopedics and dermatology, both in diagnosis and in therapy. In vitro studies may help to evaluate the mechanism by which LF-EMFs affect biological systems. In vitro model of wound healing used keratinocytes (HaCaT), neuroblastoma cell line (SH-SY5Y) as a model for analysis of differentiation, metabolism and functions related to neurodegenerative processes, and monocytic cell line (THP-1) was used as a model for inflammation and cytokines production, while leukemic cell line (K562) was used as a model for hematopoietic differentiation. MCP-1, a chemokine that regulates the migration and infiltration of memory T cells, natural killer (NK), monocytes and epithelial cells, has been demonstrated to be induced and involved in various diseases. Since, varying the parameters of EMFs different effects may be observed, we have studied MCP-1 expression in HaCaT, SH-SY5Y, THP-1 and K562 exposed to a sinusoidal EMF at 50 Hz frequency with a flux density of 1 mT (rms). Our preliminary results showed that EMF-exposure differently modifies the expression of MCP-1 in different cell types. Thus, the MCP-1 expression needs to be better determined, with additional studies, with different parameters and times of exposure to ELF-EMF.
Collapse
Affiliation(s)
- C D'Angelo
- Dept. Experimental and Clinical Sciences, Immunodiagnostic and Molecular Pathology Section, University "G. d'Annunzio" Chieti-Pescara, Italy
| | - E Costantini
- Dept. Experimental and Clinical Sciences, Immunodiagnostic and Molecular Pathology Section, University "G. d'Annunzio" Chieti-Pescara, Italy
| | - M A Kamal
- King Fahd Medical Research Center, King Abdulaziz University, P.O. Box 80216, Jeddah 21589, Saudi Arabia
| | - M Reale
- Dept. Experimental and Clinical Sciences, Immunodiagnostic and Molecular Pathology Section, University "G. d'Annunzio" Chieti-Pescara, Italy
| |
Collapse
|
24
|
Rauš Balind S, Selaković V, Radenović L, Prolić Z, Janać B. Extremely low frequency magnetic field (50 Hz, 0.5 mT) reduces oxidative stress in the brain of gerbils submitted to global cerebral ischemia. PLoS One 2014; 9:e88921. [PMID: 24586442 PMCID: PMC3929496 DOI: 10.1371/journal.pone.0088921] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2013] [Accepted: 01/16/2014] [Indexed: 11/04/2022] Open
Abstract
Magnetic field as ecological factor has influence on all living beings. The aim of this study was to determine if extremely low frequency magnetic field (ELF-MF, 50 Hz, 0.5 mT) affects oxidative stress in the brain of gerbils submitted to 10-min global cerebral ischemia. After occlusion of both carotid arteries, 3-month-old gerbils were continuously exposed to ELF-MF for 7 days. Nitric oxide and superoxide anion production, superoxide dismutase activity and index of lipid peroxidation were examined in the forebrain cortex, striatum and hippocampus on the 7th (immediate effect of ELF-MF) and 14th day after reperfusion (delayed effect of ELF-MF). Ischemia per se increased oxidative stress in the brain on the 7th and 14th day after reperfusion. ELF-MF also increased oxidative stress, but to a greater extent than ischemia, only immediately after cessation of exposure. Ischemic gerbils exposed to ELF-MF had increased oxidative stress parameters on the 7th day after reperfusion, but to a lesser extent than ischemic or ELF-MF-exposed animals. On the 14th day after reperfusion, oxidative stress parameters in the brain of these gerbils were mostly at the control levels. Applied ELF-MF decreases oxidative stress induced by global cerebral ischemia and thereby reduces possible negative consequences which free radical species could have in the brain. The results presented here indicate a beneficial effect of ELF-MF (50 Hz, 0.5 mT) in the model of global cerebral ischemia.
Collapse
Affiliation(s)
- Snežana Rauš Balind
- Institute for Biological Research, University of Belgrade, Belgrade, Serbia
- * E-mail:
| | - Vesna Selaković
- Institute for Medical Research, Military Medical Academy, Belgrade, Serbia
| | - Lidija Radenović
- Department of Physiology and Biochemistry, Faculty of Biology, University of Belgrade, Belgrade, Serbia
| | - Zlatko Prolić
- Institute for Biological Research, University of Belgrade, Belgrade, Serbia
| | - Branka Janać
- Institute for Biological Research, University of Belgrade, Belgrade, Serbia
| |
Collapse
|
25
|
Tiwari R, Lakshmi NK, Bhargava SC, Ahuja YR. Epinephrine, DNA integrity and oxidative stress in workers exposed to extremely low-frequency electromagnetic fields (ELF-EMFs) at 132 kV substations. Electromagn Biol Med 2014; 34:56-62. [DOI: 10.3109/15368378.2013.869755] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
|
26
|
Nie Y, Chen Y, Mou Y, Weng L, Xu Z, Du Y, Wang W, Hou Y, Wang T. Low frequency magnetic fields enhance antitumor immune response against mouse H22 hepatocellular carcinoma. PLoS One 2013; 8:e72411. [PMID: 24278103 PMCID: PMC3835892 DOI: 10.1371/journal.pone.0072411] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2012] [Accepted: 07/16/2013] [Indexed: 12/05/2022] Open
Abstract
Objective Many studies have shown that magnetic fields (MF) inhibit tumor growth and influence the function of immune system. However, the effect of MF on mechanism of immunological function in tumor-bearing mice is still unclear. Methods In this study, tumor-bearing mice were prepared by subcutaneously inoculating Balb/c mice with hepatocarcinoma cell line H22. The mice were then exposed to a low frequency MF (0.4 T, 7.5 Hz) for 30 days. Survival rate, tumor growth and the innate and adaptive immune parameters were measured. Results MF treatment could prolong survival time (n = 28, p<0.05) and inhibit tumor growth (n = 9, p<0.01) in tumor-bearing mice. Moreover, this MF suppressed tumor-induced production of cytokines including interleukin-6 (IL-6), granulocyte colony- stimulating factor (G-CSF) and keratinocyte-derived chemokine (KC) (n = 9–10, p<0.05 or 0.01). Furthermore, MF exposure was associated with activation of macrophages and dendritic cells, enhanced profiles of CD4+ T and CD8+ T lymphocytes, the balance of Th17/Treg and reduced inhibitory function of Treg cells (n = 9–10, p<0.05 or 0.01) in the mice model. Conclusion The inhibitory effect of MF on tumor growth was related to the improvement of immune function in the tumor-bearing mice.
Collapse
Affiliation(s)
- Yunzhong Nie
- State Key Laboratory of Pharmaceutical Biotechnology, Division of Immunology, Medical School, Nanjing University, Nanjing, China
| | - Yueqiu Chen
- State Key Laboratory of Pharmaceutical Biotechnology, Division of Immunology, Medical School, Nanjing University, Nanjing, China
| | - Yongbin Mou
- Stomatological Hospital Affiliated Medical School, Nanjing University, Nanjing, China
| | - Leihua Weng
- State Key Laboratory of Pharmaceutical Biotechnology, Division of Immunology, Medical School, Nanjing University, Nanjing, China
| | - Zhenjun Xu
- State Key Laboratory of Pharmaceutical Biotechnology, Division of Immunology, Medical School, Nanjing University, Nanjing, China
| | - Youwei Du
- National Laboratory of Solid Microstructures, Nanjing University, Nanjing, China
| | - Wenmei Wang
- Stomatological Hospital Affiliated Medical School, Nanjing University, Nanjing, China
| | - Yayi Hou
- State Key Laboratory of Pharmaceutical Biotechnology, Division of Immunology, Medical School, Nanjing University, Nanjing, China
- Jiangsu Key Laboratory of Molecular Medicine, Nanjing University, Nanjing, China
- * E-mail: (YH); (TW)
| | - Tingting Wang
- State Key Laboratory of Pharmaceutical Biotechnology, Division of Immunology, Medical School, Nanjing University, Nanjing, China
- Jiangsu Key Laboratory of Molecular Medicine, Nanjing University, Nanjing, China
- * E-mail: (YH); (TW)
| |
Collapse
|
27
|
Bekhite MM, Figulla HR, Sauer H, Wartenberg M. Static magnetic fields increase cardiomyocyte differentiation of Flk-1+ cells derived from mouse embryonic stem cells via Ca2+ influx and ROS production. Int J Cardiol 2013; 167:798-808. [DOI: 10.1016/j.ijcard.2012.02.020] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/15/2011] [Revised: 01/16/2012] [Accepted: 02/26/2012] [Indexed: 11/16/2022]
|
28
|
Could radiotherapy effectiveness be enhanced by electromagnetic field treatment? Int J Mol Sci 2013; 14:14974-95. [PMID: 23867611 PMCID: PMC3742283 DOI: 10.3390/ijms140714974] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2013] [Revised: 06/25/2013] [Accepted: 07/01/2013] [Indexed: 12/19/2022] Open
Abstract
One of the main goals in radiobiology research is to enhance radiotherapy effectiveness without provoking any increase in toxicity. In this context, it has been proposed that electromagnetic fields (EMFs), known to be modulators of proliferation rate, enhancers of apoptosis and inductors of genotoxicity, might control tumor recruitment and, thus, provide therapeutic benefits. Scientific evidence shows that the effects of ionizing radiation on cellular compartments and functions are strengthened by EMF. Although little is known about the potential role of EMFs in radiotherapy (RT), the radiosensitizing effect of EMFs described in the literature could support their use to improve radiation effectiveness. Thus, we hypothesized that EMF exposure might enhance the ionizing radiation effect on tumor cells, improving the effects of RT. The aim of this paper is to review reports of the effects of EMFs in biological systems and their potential therapeutic benefits in radiotherapy.
Collapse
|
29
|
Szerencsi Á, Kubinyi G, Váliczkó É, Juhász P, Rudas G, Mester Á, Jánossy G, Bakos J, Thuróczy G. DNA integrity of human leukocytes after magnetic resonance imaging. Int J Radiat Biol 2013; 89:870-6. [PMID: 23679232 DOI: 10.3109/09553002.2013.804962] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
PURPOSE This study focuses on the effects of high-field (3T) magnetic resonance imaging (MRI) scans on the DNA integrity of human leukocytes in vitro in order to validate the study where genotoxic effects were obtained and published by Lee et al. MATERIALS AND METHODS The scanning protocol and exposure situation were the same as those used under routine clinical brain MRI scan. Peripheral blood samples from healthy non-smoking male donors were exposed to electromagnetic fields (EMF) produced by 3T magnetic resonance imaging equipment for 0, 22, 45, 67, and 89 min during the scanning procedure. Samples of positive control were exposed to ionizing radiation (4 Gy of (60)Co-γ). Single breaks of DNA in leukocytes were detected by single-cell gel electrophoresis (Comet assay). Chromosome breakage, chromosome loss and micronuclei formations were detected by a micronucleus test (MN). Three independent experiments were performed. RESULTS The data of comet tail DNA%, olive tail moment and micronucleus frequency showed no DNA damages due to MRI exposure. CONCLUSIONS The results of the Comet assay and the micronucleus test indicate that the applied exposure of MRI does not appear to produce breaks in the DNA and has no significant effect on DNA integrity.
Collapse
Affiliation(s)
- Ágnes Szerencsi
- "Fréderic Joliot-Curie" National Research Institute for Radiobiology and Radiohygiene , Budapest
| | | | | | | | | | | | | | | | | |
Collapse
|
30
|
Akpinar D, Ozturk N, Ozen S, Agar A, Yargicoglu P. The effect of different strengths of extremely low-frequency electric fields on antioxidant status, lipid peroxidation, and visual evoked potentials. Electromagn Biol Med 2012; 31:436-48. [DOI: 10.3109/15368378.2012.692342] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Affiliation(s)
- Deniz Akpinar
- Department of Biophysics, Akdeniz University,
Antalya, Turkey
| | - Nihal Ozturk
- Department of Biophysics, Akdeniz University,
Antalya, Turkey
| | - Sukru Ozen
- Department of Electrical and Electronics Engineering, Akdeniz University,
Antalya, Turkey
| | - Aysel Agar
- Department of Physiology, Akdeniz University,
Antalya, Turkey
| | | |
Collapse
|
31
|
Ebrahimi-Kalan A, Roudkenar MH, Halabian R, Milan PB, Zarrintan A, Roushandeh AM. Down-regulation of metallothionein 1 and 2 after exposure to electromagnetic field in mouse testis. IRANIAN BIOMEDICAL JOURNAL 2012; 15:151-6. [PMID: 22395140 DOI: 10.6091/ibj.926.2012] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
BACKGROUND It is proved that testis is sensitive to electromagnetic field (EMF) and its damage results in infertility. Exposure to EMF induces reactive oxygen species production and affects on anti-oxidants defense mechanisms. Metallothionein (MT) is a name for a group of low molecular weight (6-7 kDa), sulfhydryl rich proteins. Expression of MT1 and MT2 genes in testis tissue after EMF exposure was aimed in this study. METHODS Male BALB/c mice (8 weeks old) were exposed to 3 MT EMF for 8 weeks, 4 hours/day. After 8 weeks, the mice were sacrificed and the testis tissue was removed. The testis pieces were stained with hematoxylin and eosin and analyzed under an optical microscope. Assessment of MT1 and MT2 genes and also protein expression was performed by real-time PCR and Western-blot, respectively. RESULTS In light microscopic observation, the number of primary spermatocytes was increased significantly in EMF group (P < 0.01). In addition, in interstitial space, the number of leydig cells was increased significantly in EMF group (P < 0.01) and basement membrane thickness was increased as well. MT1 and MT2 genes were down-regulated significantly in testis tissue of mice exposed to EMF both in mRNA and protein level compared to control. CONCLUSION It is clear that MT is mediated in testis development and spermatogenesis. Down-regulation of MT1 and MT2 after EMF in mouse testis might be followed by some consequences that result in infertility.
Collapse
Affiliation(s)
- Abbas Ebrahimi-Kalan
- Dept. of Anatomical Sciences, Faculty of Medicine, Medical University of Tabriz, Tabriz, Iran
| | - Mehryar Habibi Roudkenar
- Blood Transfusion Research Center, High Institute for Research and Education in Blood Transfusion Organization, Tehran, Iran
| | - Raheleh Halabian
- Blood Transfusion Research Center, High Institute for Research and Education in Blood Transfusion Organization, Tehran, Iran
| | - Peiman Broki Milan
- Dept. of Anatomical Sciences, Faculty of Medicine, Medical University of Tabriz, Tabriz, Iran
| | - Armin Zarrintan
- Dept. of Anatomical Sciences, Faculty of Medicine, Medical University of Tabriz, Tabriz, Iran
| | | |
Collapse
|
32
|
Consales C, Merla C, Marino C, Benassi B. Electromagnetic fields, oxidative stress, and neurodegeneration. Int J Cell Biol 2012; 2012:683897. [PMID: 22991514 PMCID: PMC3444040 DOI: 10.1155/2012/683897] [Citation(s) in RCA: 109] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2012] [Revised: 06/19/2012] [Accepted: 06/19/2012] [Indexed: 12/21/2022] Open
Abstract
Electromagnetic fields (EMFs) originating both from both natural and manmade sources permeate our environment. As people are continuously exposed to EMFs in everyday life, it is a matter of great debate whether they can be harmful to human health. On the basis of two decades of epidemiological studies, an increased risk for childhood leukemia associated with Extremely Low Frequency fields has been consistently assessed, inducing the International Agency for Research on Cancer to insert them in the 2B section of carcinogens in 2001. EMFs interaction with biological systems may cause oxidative stress under certain circumstances. Since free radicals are essential for brain physiological processes and pathological degeneration, research focusing on the possible influence of the EMFs-driven oxidative stress is still in progress, especially in the light of recent studies suggesting that EMFs may contribute to the etiology of neurodegenerative disorders. This review synthesizes the emerging evidences about this topic, highlighting the wide data uncertainty that still characterizes the EMFs effect on oxidative stress modulation, as both pro-oxidant and neuroprotective effects have been documented. Care should be taken to avoid methodological limitations and to determine the patho-physiological relevance of any alteration found in EMFs-exposed biological system.
Collapse
Affiliation(s)
- Claudia Consales
- Unit of Radiation Biology and Human Health, ENEA-Casaccia, Rome 00123, Italy
| | | | | | - Barbara Benassi
- Unit of Radiation Biology and Human Health, ENEA-Casaccia, Rome 00123, Italy
| |
Collapse
|
33
|
Patruno A, Pesce M, Marrone A, Speranza L, Grilli A, De Lutiis MA, Felaco M, Reale M. Activity of matrix metallo proteinases (MMPs) and the tissue inhibitor of MMP (TIMP)-1 in electromagnetic field-exposed THP-1 cells. J Cell Physiol 2012; 227:2767-74. [PMID: 21928345 DOI: 10.1002/jcp.23024] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Matrix metalloproteinases (MMPs) and tissue inhibitors of MMPs (TIMPs) are the main determinants of tissue remodeling in both physiological and pathological processes. Metabolic processes, which generate oxidants and antioxidants can be influenced by environmental factors such as electromagnetic fields (EMF). We analyzed the effects of EMF on the activity and expression of MMPs in THP-1 cells. Cells were exposed to a 50 Hz, 1 mT EMF for 24 h and incubated with or without LPS. Our data indicate that THP-1 cells exposed to EMF causes a reduction of anti-oxidant enzyme activity and an enhancement of nitrogen intermediates involving the iNOS pathway. We then analyzed the role of nitration of TIMP-1 in increasing the activity of MMPs in EMF exposed cells. Molecular modeling tools were employed to identify the most plausible sites in the active conformation of TIMP-1; at least two protein sites, Y120 and Y38 and/or Y72 were identified. Reactive nitrogen species (RNS) may affect protein targets, such as TIMP-1, which are crucial for the regulation of MMP activities by oxidation of sulfydryl groups, or by nitration of tyrosine residues. These results may suggest a pathway connecting an imbalance of MMPs and their cognate inhibitor TIMP-1.
Collapse
Affiliation(s)
- Antonia Patruno
- Department of Drug Sciences, University G. d'Annunzio, Chieti, Italy.
| | | | | | | | | | | | | | | |
Collapse
|
34
|
Pedata P, Garzillo EM, Miranda R, Antonucci A, Feola D, Miraglia N, Sannolo N, Lamberti M. Functional changes in human peripheral neutrophils in workers with different exposure to noxious agents. INTERNATIONAL JOURNAL OF ENVIRONMENTAL HEALTH RESEARCH 2012; 22:458-467. [PMID: 22369506 DOI: 10.1080/09603123.2011.654329] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Peripheral neutrophils (PMN) are a useful model to study cell activation and to evaluate the multiple stressors' interference with signalling pathways. This study aimed to evaluate the effects of different exposure to noxious agents on PMN activity by chemiluminescence assays. Two groups of office workers were recruited: peripheral whole blood cells and isolated PMNs were analyzed, performing intra- and extra-cellular chemiluminescence evaluation to study compartmental release of radical species. The exposed group shows a higher emission in resting whole blood chemiluminescence than in controls; the intracellular chemiluminescence emission in urban employees was increased, whereas the extracellular was not affected. After stimulation, the extracellular chemiluminescence was decreased in urban employees, whereas the intracellular emission did not show differences. We hypothesize that once stimulated, exposed subjects' PMNs respond to stimuli less than unexposed: PMNs could be considered indicators of chronic exposure to noxious agents.
Collapse
Affiliation(s)
- Paola Pedata
- Occupational Medicine, Hygiene and Industrial Toxicology Section, Department of Experimental Medicine, Second University of Naples, Via L. De Crecchio, 7, Naples, 80138, Italy
| | | | | | | | | | | | | | | |
Collapse
|
35
|
Extremely low frequency electromagnetic field exposure does not modulate toll-like receptor signaling in human peripheral blood mononuclear cells. Cytokine 2011; 54:43-50. [DOI: 10.1016/j.cyto.2010.12.016] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2010] [Revised: 11/08/2010] [Accepted: 12/18/2010] [Indexed: 01/23/2023]
|
36
|
Martino CF, Portelli L, McCabe K, Hernandez M, Barnes F. Reduction of the Earth's magnetic field inhibits growth rates of model cancer cell lines. Bioelectromagnetics 2010; 31:649-55. [PMID: 20830734 DOI: 10.1002/bem.20606] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2010] [Accepted: 07/14/2010] [Indexed: 11/06/2022]
Abstract
Small alterations in static magnetic fields have been shown to affect certain chemical reaction rates ex vivo. In this manuscript, we present data demonstrating that similar small changes in static magnetic fields between individual cell culture incubators results in significantly altered cell cycle rates for multiple cancer-derived cell lines. This change as assessed by cell number is not a result of apoptosis, necrosis, or cell cycle alterations. While the underlying mechanism is unclear, the implications for all cell culture experiments are clear; static magnetic field conditions within incubators must be considered and/or controlled just as one does for temperature, humidity, and carbon dioxide concentration.
Collapse
Affiliation(s)
- Carlos F Martino
- Electrical, Computer, & Energy Department, University of Colorado, Boulder, Colorado, USA.
| | | | | | | | | |
Collapse
|
37
|
Abstract
It is becoming evident that failure in the removal of dying cells causes and/or promotes the onset of chronic diseases. Impairment of phagocytosis of apoptotic cells can be due not only to genetic or molecular malfunctioning but also to external/environmental factors. Two of these environmental factors have been recently reported to down regulate the clearance of apoptotic cells: cigarette smoke and static magnetic fields. Cigarette smoke contains highly reactive carbonyls that modify proteins which directly/indirectly affects cellular function. Human macrophages interacting with carbonyl or cigarette smoke modified extracellular matrix (ECM) proteins dramatically down regulated their ability to phagocytose apoptotic neutrophils. It was postulated that changes in the ECM environment as a result of cigarette smoke affect the ability of macrophages to remove apoptotic cells. This decreased phagocytic activity was as a result of sequestration of receptors involved in the uptake of apoptotic cells towards that of recognition of carbonyl adducts on the modified ECM proteins leading to increased macrophage adhesion. Downregulation of the phagocytosis of apoptotic cells was also described when performed in presence of static magnetic fields (SMFs) of moderate intensity. SMFs have been reported to perturb distribution of membrane proteins and glycoproteins, receptors, cytoskeleton and trans-membrane fluxes of different ions, especially calcium [Ca(2+)]i, that in turn, interfere with many different physiological activities, including phagocytosis. The effects of cigarette smoke and SMF on the phagocytosis of dying cells will be here discussed.
Collapse
Affiliation(s)
- Luciana Dini
- Department Biological and Environmental Science and Technology, University of the Salento, Lecce, Italy.
| |
Collapse
|
38
|
Akan Z, Aksu B, Tulunay A, Bilsel S, Inhan-Garip A. Extremely low-frequency electromagnetic fields affect the immune response of monocyte-derived macrophages to pathogens. Bioelectromagnetics 2010; 31:603-12. [PMID: 20809504 DOI: 10.1002/bem.20607] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2009] [Accepted: 07/14/2010] [Indexed: 11/12/2022]
Abstract
This study aimed to determine the effect of extremely low-frequency electromagnetic fields (ELF-EMF) on the physiological response of phagocytes to an infectious agent. THP-1 cells (human monocytic leukemia cell line) were cultured and 50 Hz, 1 mT EMF was applied for 4-6 h to cells induced with Staphylococcus aureus or interferon gamma/lipopolysaccharide (IFγ/LPS). Alterations in nitric oxide (NO), inducible nitric oxide synthase (iNOS) levels, heat shock protein 70 levels (hsp70), cGMP levels, caspase-9 activation, and the growth rate of S. aureus were determined. The growth curve of exposed bacteria was lower than the control. Field application increased NO levels. The increase was more prominent for S. aureus-induced cells and appeared earlier than the increase in cells without field application. However, a slight decrease was observed in iNOS levels. Increased cGMP levels in response to field application were closely correlated with increased NO levels. ELF-EMF alone caused increased hsp70 levels in a time-dependent manner. When cells were induced with S. aureus or IFγ/LPS, field application produced higher levels of hsp70. ELF-EMF suppressed caspase-9 activation by a small extent. These data confirm that ELF-EMF affects bacterial growth and the response of the immune system to bacterial challenges, suggesting that ELF-EMF could be exploited for beneficial uses.
Collapse
Affiliation(s)
- Zafer Akan
- Department of Biophysics, School of Medicine, Marmara University, Istanbul, Turkey
| | | | | | | | | |
Collapse
|
39
|
Kovacic P, Somanathan R. Electromagnetic fields: mechanism, cell signaling, other bioprocesses, toxicity, radicals, antioxidants and beneficial effects. J Recept Signal Transduct Res 2010; 30:214-26. [DOI: 10.3109/10799893.2010.488650] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
|
40
|
Bernabò N, Tettamanti E, Russo V, Martelli A, Turriani M, Mattoli M, Barboni B. Extremely low frequency electromagnetic field exposure affects fertilization outcome in swine animal model. Theriogenology 2010; 73:1293-305. [PMID: 20176397 DOI: 10.1016/j.theriogenology.2009.12.010] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2009] [Revised: 12/23/2009] [Accepted: 12/27/2009] [Indexed: 11/16/2022]
Abstract
Modern society continuously exposes the population to electromagnetic radiation, the effects of which on human health, in particular reproduction, are still unknown. The aim of this research was to assess the effect of acute (1h) exposure of boar spermatozoa to a 50 Hz extremely low frequency electromagnetic field (ELF-EMF) on early fertility outcome. The effect of intensities ranging from 0 to 2 mT on morpho-functional integrity of capacitated spermatozoa was examined in vitro. The oviducts containing or without spermatozoa were then exposed to the minimum in vivo, TD(50,) and maximum intensities determined in vitro, 4h before ovulation. The effects of ELF-EMF on spermatozoa in terms of early embryo development were evaluated after 12h and 6 days. It was found that in vitro ELF-EMF > 0.5 mT induced a progressive acrosome damage, thus compromising the ability of spermatozoa to undergo acrosomal reaction after zona pellucida stimulation and reducing the in vitro fertilization outcome. These effects became evident at 0.75 mT and reached the plateau at 1 mT. Under in vivo conditions, the ELF-EMF intensity of 1 mT was able to compromise sperm function, significantly reducing the fertilization rate. In addition, the exposure of oviducts to fields > or = 0.75 mT in the absence of spermatozoa was able to negatively affect early embryo development. In fact, it was found to cause a slowdown in the embryo cleavage. In conclusion, it was demonstrated how and at which intensities ELF-EMF negatively affect early fertility outcome in a highly predictive animal model.
Collapse
Affiliation(s)
- N Bernabò
- Department of Comparative Biomedical Science, University of Teramo, 64100 Teramo, Italy
| | | | | | | | | | | | | |
Collapse
|
41
|
Exposure to ELF magnetic fields modulate redox related protein expression in mouse macrophages. Toxicol Lett 2010; 192:330-6. [DOI: 10.1016/j.toxlet.2009.11.010] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2009] [Revised: 10/24/2009] [Accepted: 11/04/2009] [Indexed: 11/20/2022]
|
42
|
Agarwal A, Desai NR, Makker K, Varghese A, Mouradi R, Sabanegh E, Sharma R. Effects of radiofrequency electromagnetic waves (RF-EMW) from cellular phones on human ejaculated semen: an in vitro pilot study. Fertil Steril 2009; 92:1318-1325. [DOI: 10.1016/j.fertnstert.2008.08.022] [Citation(s) in RCA: 164] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2008] [Revised: 07/31/2008] [Accepted: 08/07/2008] [Indexed: 01/10/2023]
|
43
|
Güler G, Türközer Z, Seyhan N. Electric Field Effects on Guinea Pig Serum: The Role of Free Radicals. Electromagn Biol Med 2009; 26:207-23. [PMID: 17886007 DOI: 10.1080/15368370701585490] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The present study was carried out to investigate the potential effects of ELF (extremely low frequency) electric field exposure on generating free radicals in guinea pigs. For this purpose, we determined thiobarbituric acid reactive substances (TBARS) levels, one of the byproducts of lipid peroxidation, the changes of the activities of superoxide dismutase (SOD), as an antioxidant enzyme, and gamma-Glutamyl transferase (GGT) as the key enzyme in GSH metabolism. Moreover, in order to investigate electric field effects on functions of organs, we measured the alanine aminotransferase (ALT) activity, alkaline phosphatase (ALP) activity, lactate dehydrogenase (LDH) activity, total cholesterol (TC), LDL cholesterol, HDL cholesterol, VLDL cholesterol, triglycerides (TG), urea, uric acid, creatin, glucose, and blood-urea nitrogen (BUN) in serum of guinea pigs exposed to different intensities and directions electric fields. In this study we have found that vertical and horizontal application of ELF electric fields in the range of 1.35, 1.5, and 1.8 kV/m increased TBARS and SOD levels as compared to the controls (p < 0.05) and to applied electric fields of 0.3, 0.6, 0.8, and 1 kV/m. On the other hand, other serum levels of some biochemical parameters that were also investigated did not undergo statistically significant changes (p > 0.05).
Collapse
Affiliation(s)
- Göknur Güler
- Department of Biophysics, Gazi University, Ankara, Turkey.
| | | | | |
Collapse
|
44
|
Lupke M, Rollwitz J, Simkó M. Cell Activating Capacity of 50 Hz Magnetic Fields to Release Reactive Oxygen Intermediates in Human Umbilical Cord Blood-derived Monocytes and in Mono Mac 6 Cells. Free Radic Res 2009; 38:985-93. [PMID: 15621717 DOI: 10.1080/10715760400000968] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
The aim of this study was to investigate the mechanism of cell activation induced by extremely low frequency magnetic fields (ELF-MF) (50 Hz) in human cells. We examined the production of free radicals in human umbilical cord blood-derived monocytes and in human Mono Mac 6 cells. The release of superoxide radical anions was analyzed using nitroblue tetrazolium chloride and the total of reactive oxygen species (ROS) was detected using dihydrorhodamine 123. Our results show a significant increase of superoxide radical anion production up-to 1.4 fold as well as an increase in ROS release up-to 1.2 fold upon exposure of monocytes to 1 mT ELF-MF (45 min). Mono Mac 6 cells exhibit higher superoxide radical anion and ROS production up-to 1.4 and 1.5 fold, respectively. These results indicate that Mono Mac 6 cells are more sensitive to ELF-MF than monocytes. Using diphenyleneiodonium chloride (DPI) a specific inhibitor for the NADPH oxidase, the MF-effect was not inhibited in Mono Mac 6 cells. Therefore, we suggest that ELF-MF exposure induces the activation of NADH oxidase in these cells. However, the MF-effect was inhibited by DPI in monocytes, indicating the activation of the NADPH oxidase after exposure to ELF-MF.
Collapse
Affiliation(s)
- Madeleine Lupke
- University of Rostock, Institute of Cell Biology and Biosystems Technology, Division of Environmental Physiology, Albert-Einstein-Str. 3, D-18059 Rostock, Germany
| | | | | |
Collapse
|
45
|
Ahuja YR, Bhargava SC, Ratnakar KS. Electric and Magnetic Fields in Stem Cell Research. Electromagn Biol Med 2009. [DOI: 10.1080/15368370500205480] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
|
46
|
Björåsen AM, Sjödin A, Mild KH, Mattsson MO. Sine Wave Extremely Low Frequency Magnetic Fields Protect Chick Embryos Against UV-Induced Death. Electromagn Biol Med 2009. [DOI: 10.1081/lebm-200037573] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
|
47
|
Güler G, Turkozer Z, Tomruk A, Seyhan N. The protective effects of N-acetyl-L-cysteine and Epigallocatechin-3-gallate on electric field-induced hepatic oxidative stress. Int J Radiat Biol 2009; 84:669-80. [DOI: 10.1080/09553000802241747] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
|
48
|
Juutilainen J, Kumlin T, Naarala J. Do extremely low frequency magnetic fields enhance the effects of environmental carcinogens? A meta-analysis of experimental studies. Int J Radiat Biol 2009; 82:1-12. [PMID: 16546898 DOI: 10.1080/09553000600577839] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
PURPOSE This paper is a meta-analysis of data from in vitro studies and short-term animal studies that have combined extremely low frequency magnetic fields with known carcinogens or other toxic physical or chemical agents. MATERIALS AND METHODS The data was analyzed by systematic comparison of study characteristics between positive and negative studies to reveal possible consistent patterns. RESULTS The majority of the studies reviewed were positive, suggesting that magnetic fields do interact with other chemical and physical exposures. Publication bias is unlikely to explain the findings. Interestingly, a nonlinear 'dose-response' was found, showing a minimum percentage of positive studies at fields between 1 and 3 mT. The radical pair mechanism (magnetic field effects on recombination of radical pairs) is a good candidate mechanism for explaining the biphasic dose-response seen in the present analysis. CONCLUSIONS Most of the studies reviewed used magnetic fields of 100 microT or higher, so the findings are not directly relevant for explaining the epidemiological findings suggesting increased risk of childhood leukemia above 0.4 microT. However, confirmed adverse effects even at 100 microT would have implications for risk assessment and management, including the need to reconsider the exposure limits for magnetic fields. There is an obvious need for further studies on combined effects with magnetic fields.
Collapse
Affiliation(s)
- Jukka Juutilainen
- University of Kuopio, Department of Environmental Sciences, Kuopio, Finland.
| | | | | |
Collapse
|
49
|
Hashish AH, El-Missiry MA, Abdelkader HI, Abou-Saleh RH. Assessment of biological changes of continuous whole body exposure to static magnetic field and extremely low frequency electromagnetic fields in mice. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2008; 71:895-902. [PMID: 17996303 DOI: 10.1016/j.ecoenv.2007.10.002] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2006] [Revised: 09/11/2007] [Accepted: 10/02/2007] [Indexed: 05/25/2023]
Abstract
The question whether static magnetic fields (SMFs) and extremely low frequency electromagnetic fields (ELF-EMF) cause biological effects is of special interest. We investigated the effects of continuous whole body exposure to both fields for 30 days on some liver and blood parameters in mice. Two exposure systems were designed; the first produced a gradient SMF while the second generated uniform 50 Hz ELF-EMF. The results showed a gradual body weight loss when mice were exposed to either field. This is coupled with a significant decrease (P<0.05) in the levels of glucose, total protein and the activity of alkaline phosphatase in serum. A significant increase in lactate dehydrogenase activity was demonstrated in serum and liver paralleled with a significant elevation in hepatic γ-glutamyl transferase activity. The glutathione-S-transferase activity and lipid peroxidation level in the liver were significantly increased while a significant decrease in hepatic gluthathione content was recorded. A significant decrease in the counts of monocytes, platelets, peripheral lymphocytes as well as splenic total, T and B lymphocytes levels was observed for SMF and ELF-EMF exposed groups. The granulocytes percentage was significantly increased. The results indicate that there is a relation between the exposure to SMF or ELF-EMF and the oxidative stress through distressing redox balance leading to physiological disturbances.
Collapse
Affiliation(s)
- A H Hashish
- Department of Physics, Faculty of Science, University of Mansoura, Mansoura 35516, Egypt
| | | | | | | |
Collapse
|
50
|
Static magnetic field selects undifferentiated myelomonocytes from low-glutamine concentration stimulated U937 cells. Tissue Cell 2008; 40:177-84. [DOI: 10.1016/j.tice.2007.11.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2007] [Revised: 11/16/2007] [Accepted: 11/27/2007] [Indexed: 11/21/2022]
|