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1.
Electromagn Biol Med ; 35(2): 126-33, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-25577980

RESUMO

This work shows the effects of exposure to an electromagnetic field at 900 MHz on the catalytic activity of the enzymes lactoperoxidase (LPO) and horseradish peroxidase (HRP). Experimental evidence that irradiation causes conformational changes of the active sites and influences the formation and stability of the intermediate free radicals is documented by measurements of enzyme kinetics, circular dichroism spectroscopy (CD) and cyclic voltammetry.


Assuntos
Peroxidase do Rábano Silvestre/metabolismo , Lactoperoxidase/metabolismo , Micro-Ondas/efeitos adversos , Domínio Catalítico/efeitos da radiação , Peroxidase do Rábano Silvestre/química , Cinética , Lactoperoxidase/química
2.
Cells ; 11(24)2022 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-36552798

RESUMO

Exposure to artificial radio frequency electromagnetic fields (RF-EMFs) has greatly increased in recent years, thus promoting a growing scientific and social interest in deepening the biological impact of EMFs on living organisms. The current legislation governing the exposure to RF-EMFs is based exclusively on their thermal effects, without considering the possible non-thermal adverse health effects from long term exposure to EMFs. In this study we investigated the biological non-thermal effects of low-level indoor exposure to RF-EMFs produced by WiFi wireless technologies, using Drosophila melanogaster as the model system. Flies were exposed to 2.4 GHz radiofrequency in a Transverse Electromagnetic (TEM) cell device to ensure homogenous controlled fields. Signals were continuously monitored during the experiments and regulated at non thermal levels. The results of this study demonstrate that WiFi electromagnetic radiation causes extensive heterochromatin decondensation and thus a general loss of transposable elements epigenetic silencing in both germinal and neural tissues. Moreover, our findings provide evidence that WiFi related radiofrequency electromagnetic fields can induce reactive oxygen species (ROS) accumulation, genomic instability, and behavioural abnormalities. Finally, we demonstrate that WiFi radiation can synergize with RasV12 to drive tumor progression and invasion. All together, these data indicate that radiofrequency radiation emitted from WiFi devices could exert genotoxic effects in Drosophila and set the stage to further explore the biological effects of WiFi electromagnetic radiation on living organisms.


Assuntos
Drosophila melanogaster , Campos Eletromagnéticos , Animais , Campos Eletromagnéticos/efeitos adversos , Drosophila melanogaster/genética , Elementos de DNA Transponíveis/genética , Ondas de Rádio/efeitos adversos , Instabilidade Genômica
3.
J Altern Complement Med ; 10(6): 947-57, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15673988

RESUMO

OBJECTIVES: The aim of the present study was to evaluate the effects of nonthermal extremely high-frequency microwave radiations in a plant-based bioassay, represented by tobacco plants reacting to tobacco mosaic virus with a hypersensitive response leading to the appearance of necrotic lesions at the infection sites. DESIGN: This study was performed blind and different experimental protocols on tobacco plants inoculated with tobacco mosaic virus were used. BIO-OBJECTS: Tobacco plants (Nicotiana tabacum L. cultivar Samsun) carrying the resistance gene N against tobacco mosaic virus. INTERVENTIONS: Tobacco plants or leaf disks were either directly or indirectly (water-mediated) irradiated using a medical device, designed for microwave resonance therapy. It produces nonthermal weak-intensity extremely high-frequency radiations, either modulated at extremely low frequency or in continuous flux of waves, coupled with a nonthermal red/near-infrared radiation. OUTCOME MEASUREMENTS: The working variable was the number of hypersensitive lesions per leaf disk. RESULTS: Both direct and indirect nonthermal microwave radiations led to significant effects on the hypersensitive response of tobacco plants: modulated radiations generally induced a resistance increase, whereas a continuous flux of waves induced a resistance decrease with direct treatments only. CONCLUSIONS: Nonthermal microwave radiations are effective on the hypersensitive response of tobacco to tobacco mosaic virus and their low-frequency modulation seems to be more bioactive than the continuous-flux of waves, particularly in the indirect water-mediated treatments.


Assuntos
Micro-Ondas , Nicotiana/efeitos da radiação , Doenças das Plantas , Folhas de Planta/efeitos da radiação , Vírus do Mosaico do Tabaco/efeitos da radiação , Bioensaio , Doenças das Plantas/virologia , Folhas de Planta/virologia , Nicotiana/virologia , Vírus do Mosaico do Tabaco/imunologia
4.
Biomatter ; 42014.
Artigo em Inglês | MEDLINE | ID: mdl-25050758

RESUMO

Magnetic force microscopy (MFM) is an atomic force microscopy (AFM) based technique in which an AFM tip with a magnetic coating is used to probe local magnetic fields with the typical AFM spatial resolution, thus allowing one to acquire images reflecting the local magnetic properties of the samples at the nanoscale. Being a well established tool for the characterization of magnetic recording media, superconductors and magnetic nanomaterials, MFM is finding constantly increasing application in the study of magnetic properties of materials and systems of biological and biomedical interest. After reviewing these latter applications, three case studies are presented in which MFM is used to characterize: (i) magnetoferritin synthesized using apoferritin as molecular reactor; (ii) magnetic nanoparticles loaded niosomes to be used as nanocarriers for drug delivery; (iii) leukemic cells labeled using folic acid-coated core-shell superparamagnetic nanoparticles in order to exploit the presence of folate receptors on the cell membrane surface. In these examples, MFM data are quantitatively analyzed evidencing the limits of the simple analytical models currently used. Provided that suitable models are used to simulate the MFM response, MFM can be used to evaluate the magnetic momentum of the core of magnetoferritin, the iron entrapment efficiency in single vesicles, or the uptake of magnetic nanoparticles into cells.


Assuntos
Materiais Revestidos Biocompatíveis/química , Microscopia de Força Atômica/métodos , Apoferritinas/química , Linhagem Celular Tumoral , Portadores de Fármacos/química , Ácido Fólico/química , Humanos , Ferro/química , Campos Magnéticos , Modelos Teóricos , Nanopartículas/química , Óxidos/química , Tamanho da Partícula , Polietilenoglicóis/química , Polilisina/química , Propriedades de Superfície
5.
Int J Environ Res Public Health ; 10(4): 1631-46, 2013 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-23603867

RESUMO

This work assesses the environmental impact from chemical emissions due to military tests and routine activities in the area occupied by the Italian Inter-force Test Range (PISQ), located at Salto di Quirra, Sardinia, Italy. After reviewing the military activities carried out at PISQ, such as rocket launching, blasting and armament destruction, projectile and mortar fire impact, the associated pollution is evaluated. Chemical analyses were performed by means of Scanning Electronic Microscopy and Energy Dispersion Spectrometry on biotic and abiotic matrices. Residues of Rb, Tl, W, Ti and Al were found in matrices collected in the PISQ areas and environs. A review of experimental data on air, water, soil, milk, forage and animal tissues obtained by various Public Agencies of Sardinia proved that toxic element residues often exceeded the legal limits. PM10 and PM2.5 air concentrations also exceeded the legal limits after military blasting. Cd and Pb contents in the liver and kidneys of sheep living in farms at PISQ and in control farms that were located more than 20 km away from PISQ were higher than the legal limits. This work was performed to investigate concentration of xenobiotics in ecosystems emitted from PISQ activities. This assessment could be useful to focus future epidemiological studies carried out in PISQ and its neighbouring areas.


Assuntos
Poluentes Ambientais/química , Instalações Militares , Agricultura , Poluição do Ar/análise , Dióxido de Carbono , Monóxido de Carbono , Monitoramento Ambiental , Substâncias Perigosas , Humanos , Itália , Metais , Material Particulado
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