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ABSTRACT: Structural and functional effects of exposing murine fibroblasts (NIH 3T3) to therapeutic ultrasound at 1 MHz frequency are described. These bioeffects can be attributed to the formation of free radical species by sonolysis of water. When cavitation occurs, dissociation of water vapor into H atoms and OH radicals is observed; these H atoms and OH radicals combine to form H(2), H(2)O(2), and HO(2). The radicals can chemically modify biomolecules, for example enzymes, DNA, and lipids. Generation of free radicals during exposure to ultrasound with or without encapsulated microbubbles (contrast agents) was studied by use of electron paramagnetic resonance with DMPO spin trapping. Recently the potential for possible use of these microbubbles in gene therapy has been investigated, because of the ability of the stabilized microbubbles to release their content when exposed to ultrasound. Structural changes were studied by Fourier-transform infrared spectroscopy, and induction of possible genotoxic damage by exposure of the cells to therapeutic ultrasound at 1 MHz frequency with our experimental device was verified by use of the cytokinesis-block micronucleus assay.
Biophysics of Structure and Mechanism 08/2011; 40(10):1115-20. · 2.44 Impact Factor
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ABSTRACT: The structural effect induced by therapeutic ultrasound on proteins in aqueous solution has been investigated with FTIR spectroscopy, UV-VIS spectroscopy, circular dichroism and light scattering. Six proteins (cytochrome, lysozyme, myoglobin, bovine serum albumin, trypsinogen, and alpha-chymotrypsinogen A) with different molecular weight and secondary structure have been studied. The experiment has been performed using an ultrasound source at resonant frequency of 1 MHz and sonication times of 10, 20, 30, 40, 50, and 60 min. A different behaviour of proteins under sonication depends on the dominant secondary structure type (alpha-helix or beta-sheets) and on the grade of the ordered structure. The results suggest that the free radicals, produced by water sonolysis, have an important role in the changes of structural order.
Ultrasonics 03/2009; 49(6-7):569-76. · 1.84 Impact Factor
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ABSTRACT: Great effort is now devolved to the study of the biological effects induced by exposure to the electromagnetic fields. Using flat strip lines and slotted cables, we realised an emitting system to irradiate a spatial region with opportune sizes and shapes. The first system provides the use of a flat strip line 8 m long, supplied by a microwave signal at the frequency in the range 900-960 MHz to reproduce a typical frequency range used by the TACS-GSM radio mobile systems. The second system, provides the use of a slotted cable 6 m long, supplied by the same microwave signal. The effective electric field emitted has been measured in a box close to the emitting system. The analysis shows that: most of the values, 88.5%, measured close to the flat strip line in a total volume whose dimensions are 800times20times6 centimetres are distributed in the range of level 1,6divide3,0 V/m; also most of the values, 77.0%, measured close to the slotted cables in a total volume whose dimensions are 600times6times10 centimetres are distributed in the range of level 1,0divide3,0 V/m. Then, the e. e. f. values produced by the strip line are distributed more uniformly than that of the slotted cable in a wider volume.
Microwave, Antenna, Propagation and EMC Technologies for Wireless Communications, 2007 International Symposium on; 09/2007
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ABSTRACT: It is presented the work performed by ISPESL, related to the analysis of the wide band electromagnetic field measurements, carried out in the urban area of Rome, in the period from 1998 to 2001. ISPESL carried out approximately 500 wide band measurements near the sites selected and proposed by the network companies for the installation of new radio base stations (SRB). The measurements have been carried out using a wide band probe equipped with an isotropic electric field probe, in areas where people stay for more than four hours. The results of the electromagnetic measurements have been compared with the electric field levels fixed by the Italian law to prevent hazardous due to long term people exposure to the electromagnetic field sources with frequency between 100 kHz-300 GHz, which is 6 V/m. The electric field levels have been shared in classes, to analyse the statistical distribution of the electric field levels measured and calculated in the urban environment of Rome.
Electromagnetic Compatibility and Electromagnetic Ecology, 2005. IEEE 6th International Symposium on; 07/2005
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ABSTRACT: Presents the work carried out by the Laboratory of Radiations and Ultrasounds Pollution of the National Institute of Occupation Safety and Prevention (ISPESL) about the measurement of radiofrequency and microwave electromagnetic field in the urban area of Rome (Italy) from 1998 to 2001. The measurements have been carried out within the framework of the technical and scientific advice paid by ISPESL to the public authority and to the companies to implement the cellular networks in TACS, GSM and DCS technologies. Presents the result of approximately 220 wide band measurements of the electromagnetic field background in the urban area of Rome, carried out near the sites selected for the installation of new base stations.
Electromagnetic Compatibility, 2003. EMC '03. 2003 IEEE International Symposium on; 06/2003
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ABSTRACT: In this study we have used for the first time the infrared spectroscopy as a tool to reveal the effects induced on a cell line, Jurkat T-lymphocytes, by ultrasound (US) used in therapy at 1 MHz frequency. We carried out the experiments using two different setups allowing to change the acoustic field parameters by varying the position of the sample with respect to the ultrasonic transducer and the sonication time with different duty cycles. The parameters of acoustic field measured by a hydrophone were compatible with the cavitation phenomenon in both setups. Genotoxic damage in exposed cells was ascertained by the cytokinesis-block micronucleus (CBMN) assay whilst cell structural changes due to sonication, were revealed by attenuated total reflection-Fourier transform infrared (ATR-FTIR) spectroscopy, a non-destructive technique that allows, by the acquisition of IR spectra within a few minutes, one to obtain simultaneous information on all cellular macromolecules in a cell population. Infrared spectroscopy results highlight changes of functional groups typical of proteins, nucleic acids and lipids at 118 J/cm2 energy dose, while the micronuclei test shows no toxic damage to the cellular samples; higher energy doses are necessary to reveal significant toxic effects together with structural changes.
Vibrational Spectroscopy 52(1):79-84. · 1.65 Impact Factor
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ABSTRACT: The structural effect induced by therapeutic ultrasound on proteins in aqueous solution has been investigated with FTIR spectroscopy, UV–VIS spectroscopy, circular dichroism and light scattering. Six proteins (cytochrome, lysozyme, myoglobin, bovine serum albumin, trypsinogen, and α-chymotrypsinogen A) with different molecular weight and secondary structure have been studied. The experiment has been performed using an ultrasound source at resonant frequency of 1 MHz and sonication times of 10, 20, 30, 40, 50, and 60 min. A different behaviour of proteins under sonication depends on the dominant secondary structure type (α-helix or β-sheets) and on the grade of the ordered structure. The results suggest that the free radicals, produced by water sonolysis, have an important role in the changes of structural order.
Ultrasonics.
