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In the last years, radiofrequency (RF) has demonstrated that it can reduce DNA damage induced by a subsequent treatment with chemical or physical agents in different cell types, resembling the adaptive response, a phenomenon well documented in radiobiology. Such an effect has also been reported by other authors both in vitro and in vivo, and plausible hypotheses have been formulated, spanning from the perturbation of the cell redox status, to DNA repair mechanisms, and stress response machinery, as possible cellular mechanisms activated by RF pre-exposure. These mechanisms may underpin the observed phenomenon, and require deeper investigations. The present study aimed to determine whether autophagy contributes to RF-induced adaptive response. To this purpose, SH-SY5Y human neuroblastoma cells were exposed for 20 h to 1950 MHz, UMTS signal, and then treated with menadione. The results obtained indicated a reduction in menadione-induced DNA damage, assessed by applying the comet assay. Such a reduction was negated when autophagy was inhibited by bafilomycin A1 and E64d. Moreover, CRISPR SH-SY5Y cell lines defective for ATG7 or ATG5 genes did not show an adaptive response. These findings suggest the involvement of autophagy in the RF-induced adaptive response in human neuroblastoma cells; although, further investigation is required to extend such observation at the molecular level.

In previous studies we demonstrated that radiofrequency (RF) electromagnetic fields (EMF) is able to reduce DNA damage induced by a subsequent treatment with genotoxic agents, resembling the adaptive response, a phenomenon well known in radiobiology. In this study we report on the capability of the culture medium from SH-SY5Y neuroblastoma cells exposed to 1950 MHz to elicit, in recipient non-exposed cells, a reduction of menadione-induced DNA damage (P < 0.05; comet assay), indicating the capability of non-ionizing radiation to elicit a bystander effect. A comparable reduction was also detected in cultures directly exposed to the same EMF conditions (P < 0.05), confirming the adaptive response. In the same exposure conditions, we also evidenced an increase of heat shock protein 70 (hsp70) in culture medium of cells exposed to RF with respect to sham exposed ones (P < 0.05; western blot analysis), while no differences were detected in the intracellular content of hsp70. On the whole, our results evidence a protective effect of RF against menadione-induced DNA damage in directly and non-directly exposed cells, and suggest hsp70 pathway to be investigated as one of the potential candidate underpinning the interaction between RF exposure and biological systems.

Background Exposure to radiofrequency electromagnetic fields (RF-EMF, 100 kHz – 300 GHz) emitted by wireless communication technologies is pervasive and ubiquitous. Concern has been raised about possible adverse effects to human health. In 2011 the International Agency for Research on Cancer has classified RF-EMF as possibly carcinogenic to humans, highlighting that the evidence is weak and far from conclusive. Updated systematic reviews of the scientific literature on this topic are lacking, especially for mechanistic studies. Objectives To develop a protocol for a systematic review of experimental studies investigating genotoxic effects induced by RF-EMF in in vitro cellular models. Genotoxicity is one of the key-biological indicators of carcinogenicity, and the most common characteristics of established carcinogens. The predefined procedures for conducting the systematic review are outlined below. Methods We will follow the guidelines developed by the National Toxicology Program-Office of Health Assessment and Translation (NTP-OHAT), adapted to the evaluation of in vitro studies. Eligibility criteria We will include experimental in vitro studies addressing the relationship between controlled exposures to RF-EMF and genotoxicity in mammalian cells only. Eligibility for inclusion will be further restricted to peer reviewed articles reporting findings from primary studies. Information sources We will search the scientific literature databases NCBI PubMed, Web of Science, and EMF-Portal. No filter on publication date will be applied. Only studies published in English will be considered. The reference lists of the included papers and available reviews will be screened for unidentified relevant papers. References will be managed through Endnote X9 software. Data extraction and synthesis of results Data from included papers will be extracted according to predefined forms. Heterogeneity within the available evidence will determine the type of evidence synthesis that is appropriate. Findings will be summarized in tables, graphical displays and in a narrative synthesis of the available evidences. A meta-analysis will be carried out if subgroups of studies homogeneous in terms of exposure characteristics, endpoint, and cell types will be identified. Risk of bias The internal validity of included studies will be assessed using the NTP-OHAT Risk of Bias Rating Tool for animal studies, adapted to in vitro studies. This stage of the process will be managed through the Health Assessment Workspace Collaborative (HAWC). Evidence appraisal To rate confidence in the body of evidence, we will use the OHAT GRADE-based approach for animal studies. Framework and funding This protocol concerns one of the evidence streams considered in a larger systematic review of the scientific literature on the potential carcinogenicity of RF-EMF, performed by scientists from several Italian public research agencies. The project is supported by the Italian Workers’ Compensation Authority (INAIL) in the framework of the CRA with the Istituto Superiore di Sanita “BRiC 2018/06 – Scientific evidence on the carcinogenicity of radiofrequency electromagnetic fields”.

Magnetic resonance imaging (MRI) is one of the most-used diagnostic imaging methods worldwide. There are ~50,000 MRI scanners worldwide each of which involves a minimum of five workers from different disciplines who spend their working days around MRI scanners. This review analyzes the state of the art of literature about the several aspects of the occupational exposure to electromagnetic fields (EMF) in MRI: regulations, literature studies on biological effects, and health surveillance are addressed here in detail, along with a summary of the main approaches for exposure assessment. The original research papers published from 2013 to 2021 in international peer-reviewed journals, in the English language, are analyzed, together with documents published by legislative bodies. The key points for each topic are identified and described together with useful tips for precise safeguarding of MRI operators, in terms of exposure assessment, studies on biological effects, and health surveillance. Graphical abstract: [Figure not available: see fulltext.]

In this paper, the circuital model of the plasma membrane of a giant squid axon, implementing the Hodgkin and Huxley equations for the initiation of action potentials, is adopted to analyze the behavior of ionic channel currents under ns pulsed electric fields (nsPEFs) stimuli. The time behavior of the currents of sodium, potassium and leakage channels is computed upon the application of liminal, subliminal and supraliminal, 100 ns long pulses. The here adopted approach allows to give insight into mechanistic details of electrostimulation of excitable cells by nsPEFs, that has been recently demonstrated by experimental studies.

In the last decades, experimental studies have been carried out to investigate the effects of radiofrequency (RF, 100 kHz–300 GHz) electromagnetic fields (EMF) exposure on the apoptotic process. As evidence-based critical evaluation of RF and apoptosis in vitro is lacking, we performed a scoping literature review with the aim of systematically mapping the research performed in this area and identifying gaps in knowledge. Eligible for inclusion were in vitro studies assessing apoptosis in mammalian cells exposed to RF-EMF, which met basic quality criteria (sham control, at least three independent experiments, appropriate dosimetry analysis and temperature monitoring). We conducted a systematic literature review and charted data in order to overview the main characteristics of included studies. From the 4362 papers retrieved with our search strategy, 121 were pertinent but, among them, only 42 met basic quality criteria. We pooled data with respect to exposure (frequency, exposure level and duration) and biological parameters (cell type, endpoint), and highlighted some qualitative trends with respect to the detection of significant effect of RF-EMF on the apoptotic process. We provided a qualitative picture of the evidence accumulated so far, and highlighted that the quality of experimental methodology still needs to be highly improved.

Millimetre wave (MMW) and THz wave (THz) applications are already employed in certain industrial and medical environments for non-destructive quality control, and medical imaging, diagnosis, and therapy, respectively. The aim of the present study is to investigate if published experimental studies (in vivo and in vitro) provide evidence for "non-thermal" biological effects of MMW and THz. Such effects would occur in absence of tissue heating and associated damage and are the ones that can be exploited for therapeutic medical use. The investigated studies provide some evidence for both MMW and THz that can influence biological systems in a manner that is not obviously driven by tissue heating. However, the number of relevant studies is very limited which severely limits the drawing of any far-reaching conclusions. Furthermore, the studies have not addressed specific interaction mechanisms and do not provide hints for future mechanistic studies. Also, the studies do not indicate any specific importance regarding power density levels, frequencies, or exposure duration. It is also unclear if any specific biological endpoints are especially sensitive. Any therapeutic potential of MMW or THz has to be evaluated based on future high-quality studies dealing with physical, bio-physical, and biological aspects that have specific health-related perspectives in mind.

The last decades have seen a huge increase in applications and devices using and emitting non-ionizing radiation, otherwise referred to as “electromagnetic fields” (EMF) [...]

In previous investigations, we demonstrated that pre-exposure of different cell cultures to radiofrequency fields can reduce the damage induced by genotoxic agents, an effect resembling the so-called adaptive response. In this study, we pre-exposed human peripheral blood lymphocytes and Chinese hamster lung fibroblast cell line to 1950 MHz, UMTS (Universal Mobile Telecommunication System) signal, for 20 h, and then treated cultures with Mitomycin-C. After confirming the induction of an adaptive response in terms of the reduction of micronuclei formation, we observed that such a response was negated by treatments with 3-aminobenzamide. Since 3-aminobenzamide is an inhibitor of poly (ADP-ribose) polymerase enzyme, which is involved in DNA repair, these results support the possible involvement of DNA repair mechanisms in radiofrequency-induced adaptive response.

Electroporation (EP) involves the application of short (ms to $\mu\mathrm{s}$ ), high voltage electric pulses to increase the permeability of biological membranes to external ions or molecules. In the clinical practice, reversible EP is used to increase the uptake of chemotherapeutic drugs in local, nonthermal tumor treatment (electrochemotherapy, ECT), by applying a standard pulsing protocol consisting of 8 rectangular pulses, 1000 V/cm electric field amplitude, $100\ \mu\mathrm{s}$ duration, 1 Hz or 5 kHz pulse repetition rate. In the standard protocol, electric pulses are used in combination with a non- permeant (bleomycin) or a low- permeant (cisplatin) anticancer drug with a very high intrinsic cytotoxicity, and are applied just after, or few minutes after, local or systemic injection of the drug. In the last decades, ECT has been increasingly used for the treatment of cutaneous and subcutaneous metastatic tumor nodules or deep-seated tumors of various histologies at different body sites, and is currently adopted in over 150 clinical centers in Europe. Recently, the use of calcium has been introduced in combination with electric pulses, as a new, EP-based cancer treatment modality (CaEP). In vitro studies have demonstrated that: 1) the introduction of supraphysiological doses of calcium into cells causes necrotic cell death associated with an acute and severe energy depletion.; 2) CaEP kills tumor cells with an efficiency similar to that of ECT with the chemotherapeutic agent bleomycin; 3) cancer cells are more sensitive to CaEP than normal cells; 4) efficacy of CaEP can be increased by optimization of pulsing conditions. The results of in vivo studies and of the first clinical trials further suggest that CaEP: 1) is very efficient at the local level on different tumor types (head and neck cancer, cutaneous metastases from breast cancer and malignant melanoma); 2) is also able to trigger a systemic immune response to target untreated metastases. Due to low intrinsic cytotoxicity of calcium, its easy preparation, handling, and storage procedures, and to the availability of electroporation equipment already used in the clinical practice, CaEP represents an effective, innovative cancer treatment technique, which can be implemented without chemotherapy, and with simplified procedure and reduced costs. An overview of CaEP will be presented in this contribution, spanning from the state of the art of basic research, to the results of recent clinical trials, and to future perspectives.

In questo intervento verrà presentata una analisi degli studi sperimentali condotti in vitro e in vivo volti alla valutazione degli effetti di esposizioni a campi elettromagnetici nel range delle onde millimetriche, incluse le frequenze che saranno impiegate per la tecnologia 5 G. Verranno descritti i risultati disponibili in letteratura con l'obiettivo di valutare se esistono evidenze di una risposta, robusta e riproducibile, nei sistemi biologici in condizioni di regime non termico e che siano in grado di fornire indicazioni sul possibile rischio per la salute umana. Inoltre, verranno anche considerate le implicazioni di tali effetti per le applicazioni diagnostiche e terapeutiche. Infine sarà discussa la qualità della ricerca in bioelettromagnetismo, che rappresenta un punto critico nella determinazione del peso dell'evidenza per la valutazione del rischio associato all'esposizione.

The occurrence of modulation-specific effects after co-exposures to radio-frequency (RF) and other agents has been discussed in the literature. In this paper, the influence of modulation and bandwidth in eliciting the DNA damage of RF alone and in combination with mitomycin-C (MMC) is analyzed in human lymphocytes. Blood cultures from healthy donors were exposed to 1950 MHz, and continuous wave (CW), wideband direct-sequence code division multiple access (WCDMA, 4.5 MHz bandwidth), and additive white Gaussian noise (AWGN, 9 MHz bandwidth) signals were considered. For each signal, specific absorption rate (SAR) values of 0.15, 0.3, 0.6, 1.25 W/kg were tested. RF exposure alone never induced DNA damage in the micronucleus assay. When RF exposure was followed by MMC treatment, the effect depended on modulation and bandwidth. CW exposure never altered the MMC-induced DNA damage, while such damage was reduced when either signals WCDMA at 0.3 W/kg SAR or AWGN at 0.15 and 0.3 W/kg were applied. These results indicate the influence of modulation for the occurrence of the protective effect, with a relation between the bandwidth and the power absorbed by samples. If confirmed in vivo , clinical applications using modulated RF signals could be devised to protect cells from side effects of therapeutic treatments.

The purpose of this review is to make a contribution to build a comprehensive knowledge of the main aspects related to the occupational exposure to electromagnetic fields (EMFs) in magnetic resonance imaging (MRI) environments. Information has been obtained from original research papers published in international peer-reviewed journals in the English language and from documents published by governmental bodies and authorities. An overview of the occupational exposure scenarios to static magnetic fields, motion-induced, time-varying magnetic fields, and gradient and radiofrequency fields is provided, together with a summary of the relevant regulation for limiting exposure. A particular emphasis is on reviewing the main EMF exposure assessment approaches found in the literature. Exposure assessment is carried out either by measuring the unperturbed magnetic fields in the MRI rooms, or by personal monitoring campaigns, or by the use of numerical methods. A general lack of standardization of the procedures and technologies adopted for exposure assessment has emerged, which makes it difficult to perform a direct comparison of results from different studies carried out by applying different assessment strategies. In conclusion, exposure assessment approaches based on data collection and numerical models need to be better defined in order to respond to specific research questions. That would provide for a more complete characterization of the exposure patterns and for identification of the factors determining the exposure variability. Graphical abstract Main approaches adopted in the literature to perform occupational exposure assessment to electromagnetic fields (EMFs) in magnetic resonance imaging (MRI) environments. SMF: static magnetic field; GMF: gradient magnetic fields; RF: radio-frequencies.

This study aims to investigate the capability of pre-exposure to 1950 MHz to protect from the amyloid beta (Abeta)-induced cytotoxicity in human neuroblastoma SH-SY5Y cells. Pre-exposure to radiofrequency (RF) reduced of about 30% the Abeta-induced DNA damage, while RF exposure alone did not affect DNA integrity, as assessed by the alkaline comet assay. Moreover, pre-exposure to RF increased microRNA 107, affecting the enzyme responsible for the Abeta plaques deposition BACE1 and decreased the expression of microRNAs related to long term potentiation and excito-toxicity (miRNA335 and miRNA26b). On the woole, RF seems to induce a protective effect against the damage induced by Abeta in human neuroblastoma cells.

La diffusione di tecnologie basate sull'utilizzo di campi elettromagnetici (CEM) negli ambienti di lavoro, ha determinato un crescente interesse verso lo sviluppo di strumenti e metodi per la valutazione del rischio per i lavoratori sottoposti a tale tipologia di esposizione. La direttiva definisce un nuovo sistema di limiti e valori di azione, e prescrive l'obbligo per i datori di lavoro di effettuare la valutazione del rischio, e di informare e formare i lavoratori rispetto all'esito di tale valutazione. I sistemi per Imaging a Risonanza Magnetica (MRI) sono sorgenti di esposizioni multiple a CEM: campi di induzione magnetica statici (fino ad alcuni T), CM di bassa frequenza (campi di gradiente) e CEM impulsivi a radiofrequenza (RF). Gli scenari di esposizione dipendono dall'attività svolta (tecnici, infermieri, medici, addetti alla pulizia o alla manutenzione) e dal layout dell'impianto MRI. Dal 2012 al 2017 l'INAIL-CONTARP Regione Campania e il CNR-IREA hanno svolto un'intensa attività di valutazione del rischio a CM, bio-monitoraggio, formazione e informazione dei lavoratori in ambienti MRI, mettendo a punto strumenti e procedure che possono essere utilizzati dal datore di lavoro e dai responsabili per la sicurezza.

There are many diagnostic and therapeutic situations where presently available tools (physical, chemical, biological) are insufficient. The search for improved approaches includes investigations of the usefulness of millimetre (MMW) and terahertz waves (THz). Here we investigated if published in vivo and in vitro studies provide support for the use of these waveforms in therapeutic applications, during conditions that do not cause tissue heating. Our conclusion is that there is some evidence for that both MMW and THz can influence biological systems in a manner that is not obviously driven by tissue heating. However, the number of relevant studies is very low which limits the drawing of any far-reaching conclusions.

This study aims to assess whether a 1950 MHz radiofrequency (RF) electromagnetic feld could protect human neuroblastoma SH-SY5Y cells against a subsequent treatment with menadione, a chemical agent inducing DNA damage via reactive oxygen species formation. Cells were pre-exposed for 20h to specifc absorption rate of either 0.3 or 1.25W/kg, and 3h after the end of the exposure, they were treated with 10µM menadione (MD) for 1h. No diferences were observed between sham- and RFexposed samples. A statistically signifcant reduction in menadione-induced DNA damage was detected in cells pre-exposed to either 0.3 or 1.25W/kg (P

Reversible electroporation is used to increase the uptake of chemotherapeutic drugs in local tumor treatment (electrochemotherapy) by applying the pulsing protocol (8 rectangular pulses, 1000 V/cm, 100 µs) standardized in the framework of the European Standard Operating Procedure on Electrochemotherapy multicenter trial. Currently, new electrochemotherapy strategies are under development to extend its applicability to tumors with different histology. Electrical parameters and drug type are critical factors. A possible approach is to test pulse parameters different from European Standard Operating Procedure on Electrochemotherapy but with comparable electroporation yield (European Standard Operating Procedure on Electrochemotherapy-equivalent protocols). Moreover, the use of non-toxic drugs combined with electroporation represents the new frontier for electrochemotherapy applications; calcium electroporation has been recently proposed as a simple tool for anticancer therapy. In vitro investigations facilitate the optimization of electrical parameters and drugs for in vivo and clinical testing. In this optimization study, new pulsing protocols have been tested by increasing the pulse number and reducing the electric field with respect to the standard. European Standard Operating Procedure on Electrochemotherapy-equivalent protocols have been identified in HL-60 and A431 cancer cell models, and a higher sensitivity in terms of electroporation yield has been recorded in HL-60 cells. Moreover, cell killing efficacy of European Standard Operating Procedure on Electrochemotherapy-equivalent protocols has been demonstrated in the presence of increasing calcium concentrations on both cell lines. Equivalent European Standard Operating Procedure on Electrochemotherapy protocols can be used to optimize the therapeutic effects in the clinic, where different regions of the same cancer tissue, with different electrical properties, might result in a differential electroporation yield of the standard protocol over the same tissue, or, eventually, in an override of the operational limits of the instrument. Moreover, using calcium can help overcome the drawbacks of standard drugs (side effects, high costs, difficult handling, preparation, and storage procedures). These results support the possibility of new treatment options in both standard electrochemotherapy and calcium electroporation, with clear advantages in the clinic.

We report here a new procedure for THz timedomain spectroscopic analysis of mammalian cell samples exposed to electroporating pulsed electric fields. Suspensions of human monocytes, Mono-Mac 6 (MM-6), were exposed to 8, 100 ?s, 400 V (100 kV/m between the cuvette electrodes) pulses at 5 kHz, and then their spectral response between 0.2 and 1.5 THz was recorded with a commercial THz time-domain spectrometer. Pulse-exposed cells absorb more THz radiation than sham-exposed cells, suggesting that THz spectroscopy can be used as a powerful, labelfree method for characterization of electroporation.

In this paper, we study the influence of radiofrequency signal modulation and bandwidth, in eliciting the genotoxic effect of radiofrequency per se and in combination with Mitomycin-C, a chemical mutagen, in a combined exposure protocol on cultured human lymphocytes.

ELF-MF exposures have been described to modulate oxidative responses. A recent review indicated changes in oxidative status as an early response to ELF-MF, although the interaction mechanisms are still lacking. Here we aim to address Reactive Oxygen Species formation in immune relevant cells during ELF-MF exposure, and to investigate if intracellular localized temperature increase (hot spots) is involved.

Pulsed electric fields (PEFs) for permeabilization of biological membranes have gained increasing consensus in the last decades for medical and industrial applications. Since ten years, our research groups have been studying the basic mechanisms of cellular responses to microsecond and nanosecond PEFs, by developing innovative experimental and modeling approaches

An ongoing research project aimed to investigate if autophagy is involved in the radiofrequency-induced adaptive response will be presented. It is funded by the ANSES and the activities, carried out in cooperation between Italian and France laboratories, will be described

I sistemi per Imaging a Risonanza Magnetica (MRI) costituiscono una sorgente di esposizioni multiple a campi elettromagnetici (CEM) per gli operatori del settore. La valutazione del rischio da esposizione ai CEM è particolarmente complessa considerando anche i diversi scenari di esposizione che dipendono dall'attività specifica svolta (tecnici, infermieri, medici, addetti alla pulizia o alla manutenzione), oltre che dal layout dell'impianto MRI. In questo lavoro verranno presentati i risultati di uno studio pilota condotto sui lavoratori MRI dell'Istituto Nazionale Tumori, Fondazione G. Pascale di Napoli, con il duplice obiettivo di valutare i livelli di esposizione e di identificare potenziali biomarcatori per la valutazione del rischio.

Electroporation (electropermeabilization) increases the electrical conductivity of biological cell membranes and lowers transport barriers for normally impermeant materials. Molecular simulations suggest that electroporation begins with the reorganization of water and lipid head group dipoles in the phospholipid bilayer interface, driven by an externally applied electric field, and the evolution of the resulting defects into water-filled, lipid pores. The interior of the electroporated membrane thus contains water, which should provide a signature for detection of the electropermeabilized state. In this feasibility study, we use THz time-domain spectroscopy, a powerful tool for investigating biomolecular systems and their interactions with water, to detect electroporation in human cells subjected to permeabilizing pulsed electric fields (PEFs). The time-domain response of electroporated human monocytes was acquired with a commercial THz, time-domain spectrometer. For each sample, frequency spectra were calculated, and the absorption coefficient and refractive index were extracted in the frequency range between 0.2 and 1.5 THz. This analysis reveals a higher absorption of THz radiation by PEF-exposed cells, with respect to sham-exposed ones, consistent with the intrusion of water into the cell through the permeabilized membrane that is presumed to be associated with electroporation.

This study aims to assess whether a 1950 MHz radiofrequency (RF) electromagnetic field could protect human neuroblastoma SH-SY5Y cells against a subsequent treatment with menadione, a chemical agent inducing DNA damage via reactive oxygen species formation. Cells were pre-exposed for 20 h to specific absorption rate of either 0.3 or 1.25 W/kg, and 3 h after the end of the exposure, they were treated with 10 µM menadione (MD) for 1 h. No differences were observed between sham- and RF-exposed samples. A statistically significant reduction in menadione-induced DNA damage was detected in cells pre-exposed to either 0.3 or 1.25 W/kg (P

Misure di campi magnetici di gradiente con metodo del picco ponderato presso impianti MRI di ospedali Campani. Bio-monitoraggio dei lavoratori esposti e di soggetti di controllo mediante analisi del danno cromosomico in campioni di mucosa buccale. Diffusione e disseminazione dei risultati in strutture pubbliche e private della Regione Campania

In this study we address the question if there is a possible correlation between reactive oxygen species formation and intracellular localized temperature increase ("hot spots") in immune relevant cells under ELF magnetic field exposure. A specific in vitro experimental procedure has been established for real-time and post-exposure measurements of ROS formation and intracellular temperature change.

Comet assay is one of the most popular tests for the detection of DNA damage at single cell level. In this study, an algorithm for comet assay analysis has been proposed, aiming to minimize user interaction and providing reproducible measurements. The algorithm comprises two-steps: (a) comet identification via Gaussian pre-filtering and morphological operators; (b) comet segmentation via fuzzy clustering. The algorithm has been evaluated using comet images from human leukocytes treated with a commonly used DNA damaging agent. A comparison of the proposed approach with a commercial system has been performed. Results show that fuzzy segmentation can increase overall sensitivity, giving benefits in bio-monitoring studies where weak genotoxic effects are expected.