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Askaripour K, Żak A. A systematic review on cellular responses of Escherichia coli to nonthermal electromagnetic irradiation. Bioelectromagnetics 2024; 45:16-29. [PMID: 37807247 DOI: 10.1002/bem.22484] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2022] [Revised: 06/23/2023] [Accepted: 08/07/2023] [Indexed: 10/10/2023]
Abstract
Investigation of Escherichia coli under electromagnetic fields is of significance in human studies owing to its short doubling time and human-like DNA mechanisms. The present review aims to systematically evaluate the literature to conclude causality between 0 and 300 GHz electromagnetic fields and biological effects in E. coli. To that end, the OHAT methodology and risk of bias tool were employed. Exponentially growing cells exposed for over 30 min at temperatures up to3 7 ∘ C $3{7}^{\circ }\,{\rm{C}}$ with fluctuations below1 ∘ C ${1}^{\circ }\,{\rm{C}}$ were included from the Web-of-Knowledge, PubMed, or EMF-Portal databases. Out of 904 records identified, 25 articles satisfied the selection criteria, with four excluded during internal validation. These articles examined cell growth (11 studies), morphology (three studies), and gene regulation (11 studies). Most experiments (85%) in the included studies focused on the extremely low-frequency (ELF) range, with 60% specifically at 50 Hz. Changes in growth rate were observed in 74% of ELF experiments and 71% of radio frequency (RF) experiments. Additionally, 80% of ELF experiments showed morphology changes, while gene expression changes were seen in 33% (ELF) and 50% (RF) experiments. Due to the limited number of studies, especially in the intermediate frequency and RF ranges, establishing correlations between EMF exposure and biological effects on E. coli is not possible.
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Affiliation(s)
- Khadijeh Askaripour
- Department of Biomechatronics, Gdansk University of Technology, Gdansk, Pomorskie, Poland
| | - Arkadiusz Żak
- Department of Biomechatronics, Gdansk University of Technology, Gdansk, Pomorskie, Poland
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Regulatory and Enterotoxin Gene Expression and Enterotoxins Production in Staphylococcus aureus FRI913 Cultures Exposed to a Rotating Magnetic Field and trans-Anethole. Int J Mol Sci 2022; 23:ijms23116327. [PMID: 35683006 PMCID: PMC9181688 DOI: 10.3390/ijms23116327] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2022] [Revised: 06/02/2022] [Accepted: 06/04/2022] [Indexed: 11/29/2022] Open
Abstract
The study aimed to examine the influence of a rotating magnetic field (RMF) of two different frequencies (5 and 50 Hz) on the expression of regulatory (agrA, hld, rot) and staphylococcal enterotoxin (SE—sea, sec, sel) genes as well as the production of SEs (SEA, SEC, SEL) by the Staphylococcus aureus FRI913 strain cultured on a medium supplemented with a subinhibitory concentration of trans-anethole (TA). Furthermore, a theoretical model of interactions between the bacterial medium and bacterial cells exposed to RMF was proposed. Gene expression and SEs production were measured using quantitative real-time PCR and ELISA techniques, respectively. Based on the obtained results, it was found that there were no significant differences in the expression of regulatory and SE genes in bacteria simultaneously cultured on a medium supplemented with TA and exposed to RMF at the same time in comparison to the control (unexposed to TA and RMF). In contrast, when the bacteria were cultured on a medium supplemented with TA but were not exposed to RMF or when they were exposed to RMF of 50 Hz (but not to TA), a significant increase in agrA and sea transcripts as compared to the unexposed control was found. Moreover, the decreased level of sec transcripts in bacteria cultured without TA but exposed to RMF of 50 Hz was also revealed. In turn, a significant increase in SEA and decrease in SEC and SEL production was observed in bacteria cultured on a medium supplemented with TA and simultaneously exposed to RMFs. It can be concluded, that depending on SE and regulatory genes expression as well as production of SEs, the effect exerted by the RMF and TA may be positive (i.e., manifests as the increase in SEs and/or regulatory gene expression of SEs production) or negative (i.e., manifests as the reduction in both aforementioned features) or none.
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Proner MC, de Meneses AC, Veiga AA, Schlüter H, Oliveira DD, Luccio MD. Industrial Cooling Systems and Antibiofouling Strategies: A Comprehensive Review. Ind Eng Chem Res 2021. [DOI: 10.1021/acs.iecr.0c05985] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Mariane Carolina Proner
- Department of Chemical and Food Engineering, Federal University of Santa Catarina (UFSC), Florianópolis, Santa Catarina 88040-900, Brazil
| | - Alessandra Cristina de Meneses
- Department of Chemical and Food Engineering, Federal University of Santa Catarina (UFSC), Florianópolis, Santa Catarina 88040-900, Brazil
| | - Andrea Azevedo Veiga
- Petrobras R&D Center, CENPES, Av. Horácio Macedo, 950, Cidade Universitária, Ilha do Fundão, Rio de Janeiro, Rio de Janeiro 21941-915, Brazil
| | - Helga Schlüter
- Petrobras R&D Center, CENPES, Av. Horácio Macedo, 950, Cidade Universitária, Ilha do Fundão, Rio de Janeiro, Rio de Janeiro 21941-915, Brazil
| | - Débora de Oliveira
- Department of Chemical and Food Engineering, Federal University of Santa Catarina (UFSC), Florianópolis, Santa Catarina 88040-900, Brazil
| | - Marco Di Luccio
- Department of Chemical and Food Engineering, Federal University of Santa Catarina (UFSC), Florianópolis, Santa Catarina 88040-900, Brazil
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Del Re B, Giorgi G. Long INterspersed element-1 mobility as a sensor of environmental stresses. ENVIRONMENTAL AND MOLECULAR MUTAGENESIS 2020; 61:465-493. [PMID: 32144842 DOI: 10.1002/em.22366] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/26/2019] [Revised: 03/03/2020] [Accepted: 03/04/2020] [Indexed: 06/10/2023]
Abstract
Long INterspersed element (LINE-1, L1) retrotransposons are the most abundant transposable elements in the human genome, constituting approximately 17%. They move by a "copy-paste" mechanism, involving reverse transcription of an RNA intermediate and insertion of its cDNA copy at a new site in the genome. L1 retrotransposition (L1-RTP) can cause insertional mutations, alter gene expression, transduce exons, and induce epigenetic dysregulation. L1-RTP is generally repressed; however, a number of observations collected over about 15 years revealed that it can occur in response to environmental stresses. Moreover, emerging evidence indicates that L1-RTP can play a role in the onset of several neurological and oncological diseases in humans. In recent years, great attention has been paid to the exposome paradigm, which proposes that health effects of an environmental factor should be evaluated considering both cumulative environmental exposures and the endogenous processes resulting from the biological response. L1-RTP could be an endogenous process considered for this application. Here, we summarize the current understanding of environmental factors that can affect the retrotransposition of human L1 elements. Evidence indicates that L1-RTP alteration is triggered by numerous and various environmental stressors, such as chemical agents (heavy metals, carcinogens, oxidants, and drugs), physical agents (ionizing and non-ionizing radiations), and experiential factors (voluntary exercise, social isolation, maternal care, and environmental light/dark cycles). These data come from in vitro studies on cell lines and in vivo studies on transgenic animals: future investigations should be focused on physiologically relevant models to gain a better understanding of this topic.
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Affiliation(s)
- Brunella Del Re
- Department of Pharmacy and Biotechnology, Alma Mater Studiorum University of Bologna, Bologna, Italy
| | - Gianfranco Giorgi
- Department of Biological, Geological and Environmental Sciences, Alma Mater Studiorum University of Bologna, Bologna, Italy
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Makinistian L, Marková E, Belyaev I. A high throughput screening system of coils for ELF magnetic fields experiments: proof of concept on the proliferation of cancer cell lines. BMC Cancer 2019; 19:188. [PMID: 30819144 PMCID: PMC6396543 DOI: 10.1186/s12885-019-5376-z] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2018] [Accepted: 02/18/2019] [Indexed: 12/26/2022] Open
Abstract
Background It has been demonstrated that relatively small variations of the parameters of exposure to extremely low frequency magnetic fields (ELF-MF) can change significantly the outcome of experiments. Hence, either in trying to elucidate if these fields are carcinogenic, or in exploring their possible therapeutic use, it is desirable to screen through as many different exposures as possible. The purpose of this work is to provide a proof of concept of how a recently reported system of coils allows testing different field exposures, in a single experiment. Methods Using a novel exposure system, we subjected a glioblastoma cancer cell line (U251) to three different time modulations of an ELF-MF at 60 different combinations of the alternated current (AC) and direct current (DC) components of the field. One of those three time modulations was also tested on another cell line, MDA-MB-231 (breast cancer). After exposure, proliferation was assessed by colorimetric assays. Results For the U251 cells, a total of 180 different exposures were tested in three different experiments. Depending on exposure modulation and AC field intensity (but, remarkably, not on DC intensity), we found the three possible outcomes: increase (14.3% above control, p < 0.01), decrease (16.6% below control, p < 0.001), and also no-effect on proliferation with respect to control. Only the time modulation that inhibited proliferation of U251 was also tested on MDA-MB-231 cells which, in contrast, showed no alteration of their proliferation on any of the 60 AC/DC field combinations tested. Conclusions We demonstrated, for the first time, the use of a novel system of coils for magnetobiology research, which allowed us to find that differences of only a few μT resulted in statistically different results. Not only does our study demonstrate the relevance of the time modulation and the importance of finely sweeping through the AC and DC amplitudes, but also, and most importantly, provides a proof of concept of a system that sensibly reduces the time and costs of screening. Electronic supplementary material The online version of this article (10.1186/s12885-019-5376-z) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Leonardo Makinistian
- Department of Radiobiology, Cancer Research Institute, Biomedical Center, Slovak Academy of Sciences, Dúbravská cesta 9, 845 05, Bratislava, Slovakia.,Department of Physics and Instituto de Física Aplicada (INFAP), Universidad Nacional de San Luis-CONICET, Ejército de los Andes 950, CP5700, San Luis, Argentina
| | - Eva Marková
- Department of Radiobiology, Cancer Research Institute, Biomedical Center, Slovak Academy of Sciences, Dúbravská cesta 9, 845 05, Bratislava, Slovakia
| | - Igor Belyaev
- Department of Radiobiology, Cancer Research Institute, Biomedical Center, Slovak Academy of Sciences, Dúbravská cesta 9, 845 05, Bratislava, Slovakia.
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Saliev T, Begimbetova D, Masoud AR, Matkarimov B. Biological effects of non-ionizing electromagnetic fields: Two sides of a coin. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2018; 141:25-36. [PMID: 30030071 DOI: 10.1016/j.pbiomolbio.2018.07.009] [Citation(s) in RCA: 56] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/11/2018] [Revised: 07/12/2018] [Accepted: 07/16/2018] [Indexed: 12/12/2022]
Abstract
Controversial, sensational and often contradictory scientific reports have triggered active debates over the biological effects of electromagnetic fields (EMFs) in literature and mass media the last few decades. This could lead to confusion and distraction, subsequently hampering the development of a univocal conclusion on the real hazards caused by EMFs on humans. For example, there are lots of publications indicating that EMF can induce apoptosis and DNA strand-breaks in cells. On the other hand, these effects could rather be beneficial, in that they could be effectively harnessed for treatment of various disorders, including cancer. This review discusses and analyzes the results of various in vitro, in vivo and epidemiological studies on the effects of non-ionizing EMFs on cells and organs, including the consequences of exposure to the low and high frequencies EM spectrum. Emphasis is laid on the analysis of recent data on the role of EMF in the induction of oxidative stress and DNA damage. Additionally, the impact of EMF on the reproductive system has been discussed, as well as the relationship between EM radiation and blood cancer. Apart from adverse effects, the therapeutic potential of EMFs for clinical use in different pathologies is also highlighted.
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Affiliation(s)
- Timur Saliev
- Kazakh National Medical University Named After S.D. Asfendiyarov, Tole Bi Street 94, Almaty, 050000, Kazakhstan; National Laboratory Astana, Nazarbayev University, 53 Kabanbay batyr Ave., Astana, 010000, Kazakhstan.
| | - Dinara Begimbetova
- National Laboratory Astana, Nazarbayev University, 53 Kabanbay batyr Ave., Astana, 010000, Kazakhstan
| | - Abdul-Razak Masoud
- National Laboratory Astana, Nazarbayev University, 53 Kabanbay batyr Ave., Astana, 010000, Kazakhstan
| | - Bakhyt Matkarimov
- National Laboratory Astana, Nazarbayev University, 53 Kabanbay batyr Ave., Astana, 010000, Kazakhstan
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Consales C, Merla C, Marino C, Benassi B. The epigenetic component of the brain response to electromagnetic stimulation in Parkinson's Disease patients: A literature overview. Bioelectromagnetics 2017; 39:3-14. [PMID: 28990199 DOI: 10.1002/bem.22083] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2017] [Accepted: 08/20/2017] [Indexed: 12/12/2022]
Abstract
Modulations of epigenetic machinery, namely DNA methylation pattern, histone modification, and non-coding RNAs expression, have been recently included among the key determinants contributing to Parkinson's Disease (PD) aetiopathogenesis and response to therapy. Along this line of reasoning, a set of experimental findings are highlighting the epigenetic-based response to electromagnetic (EM) therapies used to alleviate PD symptomatology, mainly Deep Brain Stimulation (DBS) and Transcranial Magnetic Stimulation (TMS). Notwithstanding the proven efficacy of EM therapies, the precise molecular mechanisms underlying the brain response to these types of stimulations are still far from being elucidated. In this review we provide an overview of the epigenetic changes triggered by DBS and TMS in both PD patients and neurons from different experimental animal models. Furthermore, we also propose a critical overview of the exposure modalities currently applied, in order to evaluate the technical robustness and dosimetric control of the stimulation, which are key issues to be carefully assessed when new molecular findings emerge from experimental studies. Bioelectromagnetics. 39:3-14, 2018. © 2017 Wiley Periodicals, Inc.
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Affiliation(s)
- Claudia Consales
- ENEA-Italian National Agency for New Technologies, Energy and Sustainable Economic Development, Rome, Italy
| | - Caterina Merla
- ENEA-Italian National Agency for New Technologies, Energy and Sustainable Economic Development, Rome, Italy.,CNRS, Gustave Roussy, University of Paris-Sud, Université Paris-Saclay, Villejuif, France
| | - Carmela Marino
- ENEA-Italian National Agency for New Technologies, Energy and Sustainable Economic Development, Rome, Italy
| | - Barbara Benassi
- ENEA-Italian National Agency for New Technologies, Energy and Sustainable Economic Development, Rome, Italy
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Mercier A, Bertaux J, Lesobre J, Gravouil K, Verdon J, Imbert C, Valette E, Héchard Y. Characterization of biofilm formation in natural water subjected to low-frequency electromagnetic fields. BIOFOULING 2016; 32:287-299. [PMID: 26905178 DOI: 10.1080/08927014.2015.1137896] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Electromagnetic field (EMF) treatment has proven to be effective against mineral scaling in water systems. Therefore, it should be assessed for the treatment of other deposits such as biofilms. In this study, a commercial device producing low-frequency EMF (1-10 kHz) was applied to a reactor fed with natural water for 45 days. The treatment promoted the concentration of microorganisms in suspension and limited the amount of sessile microorganisms in the biofilm, as determined by the measurement of total DNA, qPCR and microscopy. The structure of the bacterial community was assessed by t-RFLP and pyrosequencing analysis. The results showed that EMF treatment affected both planktonic and sessile community composition. EMFs were responsible for a shift in classes of Proteobacteria during development of the biofilm. It may be speculated that the EMF treatment affected particle solubility and/or microorganism hydration. This study indicated that EMFs modulated biofilm formation in natural water.
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Affiliation(s)
- Anne Mercier
- a Equipe Microbiologie de l'Eau, Ecologie et Biologie des Interactions, Centre National de la Recherche Scientifique UMR 7267 , Université de Poitiers , Poitiers , France
| | - Joanne Bertaux
- b Equipe Ecologie Evolution Symbiose, Ecologie et Biologie des Interactions, Centre National de la Recherche Scientifique UMR 7267 , Université de Poitiers , Poitiers , France
| | - Jérôme Lesobre
- a Equipe Microbiologie de l'Eau, Ecologie et Biologie des Interactions, Centre National de la Recherche Scientifique UMR 7267 , Université de Poitiers , Poitiers , France
- b Equipe Ecologie Evolution Symbiose, Ecologie et Biologie des Interactions, Centre National de la Recherche Scientifique UMR 7267 , Université de Poitiers , Poitiers , France
| | - Kevin Gravouil
- c Laboratoire coopératif ThanaplastSP-EBI-Carbios Bioplastics, Ecologie et Biologie des Interactions, Centre National de la Recherche Scientifique UMR 7267 , Université de Poitiers , Poitiers , France
| | - Julien Verdon
- a Equipe Microbiologie de l'Eau, Ecologie et Biologie des Interactions, Centre National de la Recherche Scientifique UMR 7267 , Université de Poitiers , Poitiers , France
| | - Christine Imbert
- a Equipe Microbiologie de l'Eau, Ecologie et Biologie des Interactions, Centre National de la Recherche Scientifique UMR 7267 , Université de Poitiers , Poitiers , France
| | - Eric Valette
- d Planet Horizons Technologies , Technopole 5, Sierre , Switzerland
| | - Yann Héchard
- a Equipe Microbiologie de l'Eau, Ecologie et Biologie des Interactions, Centre National de la Recherche Scientifique UMR 7267 , Université de Poitiers , Poitiers , France
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Spasić S, Kesić S, Stojadinović G, Petković B, Todorović D. Effects of the static and ELF magnetic fields on the neuronal population activity in Morimus funereus (Coleoptera, Cerambycidae) antennal lobe revealed by wavelet analysis. Comp Biochem Physiol A Mol Integr Physiol 2015; 181:27-35. [DOI: 10.1016/j.cbpa.2014.11.018] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2014] [Revised: 11/19/2014] [Accepted: 11/20/2014] [Indexed: 12/21/2022]
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Del Re B, Giorgi G. Cell-host, LINE and environment: Three players in search of a balance. Mob Genet Elements 2014; 3:e24040. [PMID: 23734298 PMCID: PMC3655780 DOI: 10.4161/mge.24040] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2013] [Revised: 02/13/2013] [Accepted: 02/18/2013] [Indexed: 12/19/2022] Open
Abstract
Long interspersed nuclear elements -1 (LINEs, L1s) are retroelements occupying almost 17% of the human genome. L1 retrotransposition can cause deleterious effects on the host-cell and it is generally inhibited by suppressive mechanisms, but it can occur in some specific cells during early development as well as in some tumor cells and in the presence of several environmental factors. In a recent publication we reported that extremely low frequency pulsed magnetic field can affect L1 retrotransposition in neuroblastoma cells. In this commentary we discuss the interaction between environment and L1 activity in the light of the new emerging paradigm of host-LINE relationship.
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Affiliation(s)
- Brunella Del Re
- Department of Pharmacy and Biotechnology; University of Bologna; Bologna, Italy
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Nawrotek P, Fijałkowski K, Struk M, Kordas M, Rakoczy R. Effects of 50 Hz rotating magnetic field on the viability ofEscherichia coliandStaphylococcus aureus. Electromagn Biol Med 2013; 33:29-34. [DOI: 10.3109/15368378.2013.783848] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Del Re B, Marcantonio P, Gavoçi E, Bersani F, Giorgi G. Assessing LINE-1 retrotransposition activity in neuroblastoma cells exposed to extremely low-frequency pulsed magnetic fields. Mutat Res 2012; 749:76-81. [PMID: 22981769 DOI: 10.1016/j.mrgentox.2012.07.004] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2012] [Revised: 06/05/2012] [Accepted: 07/25/2012] [Indexed: 06/01/2023]
Abstract
Mobile genetic elements represent an important source of mutation and genomic instability, and their activity can be influenced by several chemical and physical agents. In this research we address the question whether exposure to extremely low-frequency pulsed magnetic fields (EMF-PMF) could affect the mobility of the human LINE-1(RP) retrotransposon. To this purpose, an in vitro retrotransposition assay was used on human neuroblastoma BE(2) cells exposed for 48h to 1mT, 50Hz PMF, or sham-exposed. Moreover, since it is well known that retrotransposition causes DNA double-strand breaks (DSB), an estimation of γ-H2AX foci, which is a marker of DNA DSB, was carried out on PMF- and sham-exposed samples. The results show that PMF-exposed cells had a lower number of both retrotransposition events and DNA DSB compared with sham-exposed samples. These results suggest that exposure to PMF can interfere with retrotransposition activity by inducing a decrease of retrotransposition events.
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Affiliation(s)
- Brunella Del Re
- Department of Experimental Evolutionary Biology, University of Bologna, Bologna, Italy.
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Evaluations of the Effects of Extremely Low-Frequency Electromagnetic Fields on Growth and Antibiotic Susceptibility of Escherichia coli and Pseudomonas aeruginosa. Int J Microbiol 2012; 2012:587293. [PMID: 22577384 PMCID: PMC3335185 DOI: 10.1155/2012/587293] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2011] [Accepted: 01/26/2012] [Indexed: 12/02/2022] Open
Abstract
We aimed to investigate the effects of exposure to extremely low-frequency electromagnetic fields (2 mT; 50 Hz) on the growth rate and antibiotic sensitivity of E. coli ATCC 25922 and P. aeruginosa ATCC 27853. The electromagnetic field treatment significantly influenced the growth rate of both strains when incubated in the presence of subinhibitory concentrations of kanamycin (1 μg/mL) and amikacin (0.5 μg/mL), respectively. In particular, at 4, 6, and 8 h of incubation the number of cells was significantly decreased in bacteria exposed to electromagnetic field when compared with the control. Additionally, at 24 h of incubation, the percentage of cells increased (P. aeruginosa∼42%; E. coli∼5%) in treated groups with respect to control groups suggesting a progressive adaptive response. By contrast, no remarkable differences were found in the antibiotic susceptibility and on the growth rate of both bacteria comparing exposed groups with control groups.
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