18 GHz electromagnetic field induces permeability of Gram-positive cocci

Nguyen, The Hong Phong; Shamis, Yury; Croft, Rodney J.; Wood, Andrew W.; McIntosh, R.; Crawford, Russell J.; Ivanova, Elena P.

doi:10.1038/srep10980

Cited by 30 publications

(59 citation statements)

References 61 publications

(143 reference statements)

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“…It is obvious that the electromagnetic field changes physicochemical properties and hydration ability of water molecules and solubility of the antibiotics in the surrounding area was changed (20,23). c) One of the factors that can influence antibacterial sensitivity is the cell wall structure of bacteria and peptidoglycan (PG) nature (3,46,47). In gram-positive bacteria, cell wall thickness is greater than that of gram negatives.…”

Section: Discussionmentioning

confidence: 99%

Evaluation of the 900 MHz Radiofrequency Radiation Effects on the Antimicrobial Susceptibility and Growth Rate of Klebsiella pneumoniae

et al. 2017

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Introduction: Drug resistance to one or more antibiotics is mainly believed to be a serious threat to global public health which occurs by various mechanisms. The electromagnetic field as a nonchemical tool is capable of altering the antimicrobial susceptibility of bacteria. The aim of this study is the evaluation of the antimicrobial susceptibility of the Klebsiella pneumoniae to antibiotics before and after exposure to 900 MHz radiofrequency (RF) radiation produced by a mobile phone.Methods: Antimicrobial susceptibility of the bacteria to antibiotics disks were performed after exposure to 900 MHz radiofrequency radiation. Antimicrobial susceptibility was carried out by Kirby-Bauer and the inhibition zone of each antibiotic disk was measured (as mean). Additionally, growth variations under exposure were recorded and an outgrowth curve was drawn.Results: Based on the results, after 12 hours of exposure to 900MHz radiofrequency, there was observed a maximum increase in the sensitivity of K. pneumoniae and shown that radiofrequency (RF) radiation can change antimicrobial sensitivity significantly (P < 0.05). Also, the radiofrequency radiation effect on the bacterial proliferation was evaluated and showed that exposure enables the bacteria to grow faster in the exponential phase than the non-exposed bacteria. Conclusions:The findings of the study indicated that the sensitivity of K. pneumoniae was significantly increased to the various antibiotics after 12 hours of exposure to 900 MHz radiofrequency radiation. These observations could be interpreted by the concept of non-linearity in the responses of K. pneumoniae to different antibiotics after exposure to electromagnetic radiofrequency radiation and can be useful in the management of serious infectious diseases.

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Section: Discussionmentioning

confidence: 99%

Evaluation of the 900 MHz Radiofrequency Radiation Effects on the Antimicrobial Susceptibility and Growth Rate of Klebsiella pneumoniae

et al. 2017

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“…Lowenergy high-frequency (51 to 73 GHz) exposure to growing Escherichia coli cells results in an elongation of cells, overall decrease in growth rate (37), and an increase in cell permeability at low frequency (2.45 GHz) (38) and high frequencies (51 to 73 GHz) (39). An increase in cell permeability was also observed in the Grampositive bacteria Planococcus maritimus, Staphylococcus aureus, and Staphylococcus epidermidis exposed to 18 GHz low-energy microwave radiation, with no subsequent change in cell morphology (40).…”

Section: Discussionmentioning

confidence: 63%

Molecular Mechanisms Contributing to the Growth and Physiology of an Extremophile Cultured with Dielectric Heating

Cusick

Lin

Malanoski

et al. 2016

Appl Environ Microbiol

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The effect of microwave frequency electromagnetic fields on living microorganisms is an active and highly contested area of research. One of the major drawbacks to using mesophilic organisms to study microwave radiation effects is the unavoidable heating of the organism, which has limited the scale (<5 ml) and duration (<1 h) of experiments. However, the negative effects of heating a mesophile can be mitigated by employing thermophiles (organisms able to grow at temperatures of >60°C). This study identified changes in global gene expression profiles during the growth of Thermus scotoductus SA-01 at 65°C using dielectric (2.45 GHz, i.e., microwave) heating. RNA sequencing was performed on cultures at 8, 14, and 24 h after inoculation to determine the molecular mechanisms contributing to long-term cellular growth and survival under microwave heating conditions. Over the course of growth, genes associated with amino acid metabolism, carbohydrate metabolism, and defense mechanisms were upregulated; the number of repressed genes with unknown function increased; and at all time points, transposases were upregulated. Genes involved in cell wall biogenesis and elongation were also upregulated, consistent with the distinct elongated cell morphology observed after 24 h using microwave heating. Analysis of the global differential gene expression data enabled the identification of molecular processes specific to the response of T. scotoductus SA-01 to dielectric heating during growth. IMPORTANCEThe residual heating of living organisms in the microwave region of the electromagnetic spectrum has complicated the identification of radiation-only effects using microorganisms for 50 years. A majority of the previous experiments used either mature cells or short exposure times with low-energy high-frequency radiation. Using global differential gene expression data, we identified molecular processes unique to dielectric heating using Thermus scotoductus SA-01 cultured over 30 h in a commercial microwave digestor. Genes associated with amino acid metabolism, carbohydrate metabolism, and defense mechanisms were upregulated; the number of repressed genes with unknown function increased; and at all time points, transposases were upregulated. These findings serve as a platform for future studies with mesophiles in order to better understand the response of microorganisms to microwave radiation. T he impact of microwave frequency (300 MHz to 300 GHz) electromagnetic fields on living organisms is of significant interest across multiple industries, including medical, food, and biotechnology (1-5). However, confirmation that a biological effect results from exposing live cells to an electromagnetic field has yet to be definitively demonstrated. Most studies to date involving the physiological or transcriptional effects of microwave radiation on living microorganisms have been performed with mesophilic bacteria, archaea (6), and select eukaryotic systems (7,8). The selection of mesophilic organisms coupled with highly varied experime...

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“…This research determined, for the first time, that regardless of the differences in cell wall/membrane structures, exposure to 18 GHz EMF induced cell permeabilisation, as confirmed via the ability of the cells to uptake silica nanospheres (23 nm and 46 nm in diameter), in all of the cell types studied, in a manner that could not be duplicated using conventional heating methods under similar bulk temperature conditions [29,30,31]. Moreover, a large proportion of the cells remained viable (85%) throughout the exposures (excluding erythrocytes) as confirmed directly using the colony-forming units counting technique.…”

Section: Mechanisms Of Interactionmentioning

confidence: 99%

“…These results are important in that the membrane effects do not occur with Peltier plate-induced equivalent bulk temperature increases, and cannot be explained via traditional electroporation mechanisms, which require brief pulsed fields [32]. It is hypothesised that the taxonomic affiliation and cell wall/membrane structures (e.g., the presence of peptidoglycan layer, mannoprotein/β-glucan layer, phosphatidyl-glycerol and/or pentadecanoic fatty acid) may affect the extent of permeabilisation to allow the uptake of 46 nm nanospheres [29,30]. However, precisely how this relates to EMF itself is not clear.…”

Section: Mechanisms Of Interactionmentioning

confidence: 99%

“…However, the electrical characteristics of biological tissue in this range, with particular emphasis on energy absorption in bacterial spores and human skin, are largely unknown. Recent ACEBR work on bacterial spores [29] indicates a possible method of infection control using THz exposure, and this work is aimed at further modelling THz absorption patterns in tissue. Given their increasing use, this work will help to determine whether the THz EMF frequencies could adversely impact on biological function and human health.…”

Section: Dosimetrymentioning

confidence: 99%

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Bioelectromagnetics Research within an Australian Context: The Australian Centre for Electromagnetic Bioeffects Research (ACEBR)

Loughran

Hossain

Bentvelzen

et al. 2016

IJERPH

Self Cite

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Mobile phone subscriptions continue to increase across the world, with the electromagnetic fields (EMF) emitted by these devices, as well as by related technologies such as Wi-Fi and smart meters, now ubiquitous. This increase in use and consequent exposure to mobile communication (MC)-related EMF has led to concern about possible health effects that could arise from this exposure. Although much research has been conducted since the introduction of these technologies, uncertainty about the impact on health remains. The Australian Centre for Electromagnetic Bioeffects Research (ACEBR) is a National Health and Medical Research Council Centre of Research Excellence that is undertaking research addressing the most important aspects of the MC-EMF health debate, with a strong focus on mechanisms, neurodegenerative diseases, cancer, and exposure dosimetry. This research takes as its starting point the current scientific status quo, but also addresses the adequacy of the evidence for the status quo. Risk communication research complements the above, and aims to ensure that whatever is found, it is communicated effectively and appropriately. This paper provides a summary of this ACEBR research (both completed and ongoing), and discusses the rationale for conducting it in light of the prevailing science.

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18 GHz electromagnetic field induces permeability of Gram-positive cocci

Cited by 30 publications

References 61 publications

Evaluation of the 900 MHz Radiofrequency Radiation Effects on the Antimicrobial Susceptibility and Growth Rate of Klebsiella pneumoniae

Evaluation of the 900 MHz Radiofrequency Radiation Effects on the Antimicrobial Susceptibility and Growth Rate of Klebsiella pneumoniae

Molecular Mechanisms Contributing to the Growth and Physiology of an Extremophile Cultured with Dielectric Heating

Bioelectromagnetics Research within an Australian Context: The Australian Centre for Electromagnetic Bioeffects Research (ACEBR)

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