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The periodic evaluation of the Faraday cage efficiency for diagnostic Magnetic Resonance is mandatory by Italian legislation and it is recommended by manufacturers. An inadequate shielding could affect clinical images with artifacts, reducing the quality of examinations. The International reference standard for shielding effectiveness measurements is represented by IEEE Standard 299-2006, but it results poorly applicable in Magnetic Resonance sites. In this study, an alternative approach is proposed to simplify the applicability of the IEEE Standard. The experimental set-up for measurements is composed by a signal generator and a transmitting antenna, coupled with the signal generator. The novelty of the proposed methodology consists in the absence of the receiver antenna; for this purpose, the Magnetic Resonance scanner is used. This approach permits to test the entire Faraday cage by means of a single measure. If the Magnetic Resonance device picks up the radiofrequency signal from outside of the cage, this would be visible on the acquired images as a "zipper" artifact. Four Faraday cages, different in building materials, were tested by using the proposed methodology, and the results were compared with those obtained by using the IEEE Standard. The presence of the "zipper" artifact on the images made us inspect the entire Faraday cage and not just the openings, finding that the radiofrequency signal entered from an area without openings, thus denoting a poor construction of the cage. The proposed methodology provides an immediate evaluation of the shielding efficiency, furnishing information on the entire Faraday cage and not only on its apertures. The method is simple, easily reproducible, and constitutes a valid alternative to the IEEE Standard; in particular, during constancy tests. [ABSTRACT FROM AUTHOR]

In order to ascertain whether erythropoietin plays a role in early and late repair processes following ischaemic skin flap injury, a dorsal, caudally based skin flap was created in rats. The rats were successively divided into four groups. Group 1 was not treated. The other groups were treated with a subcutaneous administration of 0.9% NaCl saline solution (group 2), a subcutaneous administration of vehicle (group 3) or a subcutaneous administration of 300 IU/kg/day of recombinant human erythropoietin (group 4). We evaluated the possible relationships between neutrophil accumulation, myeloperoxidase activity and content in flap tissue, flap survival, flap temperature (using telethermography) and flap revascularization (using videocapillaroscopy). Necrosis in the flap was significantly less extensive in group 4 than in groups 1, 2 and 3. A significant increase in neutrophil infiltration occurred between the 1st and 24th hour in these groups, but this was not observed in group 4. These findings were confirmed by biochemical data of myeloperoxidase activity and malonyldialdehyde content. Between the 1st and 7th days, we recorded an increase of about 20% in flap temperature in groups 1, 2 and 3, whereas no significant variation was observed in group 4. On the 7th day, videocapillaroscopic findings showed an increase in the mean vascularization index in group 4. Our findings suggest that recombinant human erythropoietin administration can improve the wound healing process, in both early and late stages of injury, by reducing inflammatory response, increasing the density of capillaries in ischaemic flaps and allowing earlier repair of a damaged area. [ABSTRACT FROM AUTHOR]