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PubMed2003

Response of disordered matter to electromagnetic fields.

We have studied a variety of different disordered materials, including molecular and ionic liquids, supercooled liquids, glasses, ionic conductors, and doped semiconductors, in ac electromagnetic fields over an exceptional broad dynamic range, including the rarely investigated GHz to THz region. All classes of disordered matter exhibit an astonishingly similar response: In addition to Jonscher's time-honored "universal dielectric response," a superlinear power-law increase of the frequency-dependent conductivity shows up bridging the gap between the classical dielectric and the infrared region. Thus the universal dielectric behavior of disordered matter extends up to much higher frequencies than thought until now.

Journal Article↗
PubMed1983

[Effect of an electromagnetic field on conditioned reflex maintenance and the nucleic acid content of brain tissues during carotid artery constriction].

It has been discovered in chronic experiments on 54 rats that during ligation of the carotid artery, the action of the decimetric electromagnetic field (DMB-irradiation) produces in some cases the deterioration of the rats' status that manifests in paroxysms eventuating in lethal outcomes, whereas in other ones, makes the conditioned reflexes return to normal, accompanied by an increase in RNA content in the cortex of the large hemispheres. The mechanisms of an inconclusive action of DMB-irradiation is discussed as is the importance of changes in RNA content in the cortex for the mechanisms of a favourable action of irradiation on the recovery of brain function in circulatory disorders. The possibilities of using DMB-irradiation under the clinical conditions are also discussed.

Animals↗
PubMed1995

Parkinsonian micrographia reversed by treatment with weak electromagnetic fields.

Micrographia is one of the characteristic clinical signs of Parkinson's disease (PD) which is linked to striatal dopaminergic deficiency. It has been reported recently that external application of weak electromagnetic fields (EMFs) in the picotesla (pT) range and of low frequency produced dramatic improvements in motor symptoms in Parkinsonian patients indicating that a specific range of electromagnetic energy increases, among others, striatal dopaminergic neurotransmission. In the present communication, I present two fully mediated Parkinsonian patients who, prior to the application of EMFs, drew lilliputian sized figures reflecting the micrographia of the disease. In both patients a series of treatments with pT EMFs produced, in addition to improvement in motor symptoms, a dramatic increase in the size of their drawings with reversal of their micrographia. Since both patients were maintained on dopaminergic medications prior to and during treatment with EMFs it is suggested that Parkinsonian micrographia is related also to abnormalities of nondopaminergic systems which are affected by weak EMFs. This report corroborates previous observations demonstrating the powerful antiParkinsonian effect of pT range EMFs and highlights the unique efficacy of this treatment modality in Parkinsonism.

Aged↗
PubMed2003

Evaluation of rat thyroid gland morphophysiological status after three months exposure to 50 Hz electromagnetic field.

Objective of our study was to use morphophysiological criteria in order to determine the sensitivity of male rat thyroid gland to an extremely low frequency electromagnetic field (ELF-EMF) influence and the ability of the gland to repair after period of exposure. Animals were exposed to 50Hz, 50-500 microT ELF-EMF for 3 months when a part of them (group I) were sacrificed, while the rest of animals were subjected to recovery evaluation of the gland and sacrificed after 1 (group II), 2 (group III) and 3 (group IV) weeks. Histological and stereological analyses were performed on paraffin and semifine thyroid gland sections. Serum T3 and T4 were also determined. Histological and stereological analyses showed that the volume density of follicular epithelium and thyroid activation index decreased, while the volume density of colloid and capillary network increased in group I, II and III. The values of all these parameters in group IV were similar to corresponding controls. Serum T3 and T4 concentrations were significantly lower in all exposed animals, except in group I. Results of this study demonstrate that after significant morphophysiological changes caused by ELF-EMF exposure thyroid gland recovered morphologically, but not physiologically, during the investigated repair period.

Animals↗
PubMed1989

Effects of pulsed electromagnetic fields on Steinberg ratings of femoral head osteonecrosis.

Between 1979 and 1985, 95 patients with femoral head osteonecrosis met the protocol for treatment of 118 hips with selected pulsed electromagnetic fields (PEMFs). Etiologies included trauma (17), alcohol (9), steroid use (46), sickle cell disease (2), and idiopathy (44). The average age was 38 years, and the average follow-up period since the onset of symptoms was 5.3 years. PEMF treatment had been instituted an average of 4.1 years earlier. By the Steinberg quantitative staging method of roentgenographic analysis, none of the 15 hips in Stages 0-III showed progression, and grading improved in nine of 15. Eighteen of 79 hips (23%) with Stage IV lesions progressed and none improved. In the Stage V category, one of 21 hips (5%) worsened and none improved. Three Stage VI lesions were unchanged. The overall rate of quantified progression for the 118 hips, 87% of which had collapse present when entering the program, was 16%. This value represents a reversal of the percentage of progression reported recently by other investigators using conservative and selected surgical methods. PEMF patients also have experienced long-term improvements in symptoms and signs, together with a reduction in the need for early joint arthroplasty.

Adult↗
PubMed2003

Health risks of electromagnetic fields. Part III: Risk analysis.

The management of potential health risks from electromagnetic (EM) fields presents both scientific and nonscientific challenges. When the scientific evidence is ambiguous, as is the case with EM fields, expert judgment of this evidence becomes particularly important. This article provides biomedical researchers with a comprehensive assessment of the status of EM health risk based on our two previous articles [Parts I and II, Critical Reviews in Biomedical Engineering, Volume 31, Issue 3]. Ambiguous evidence also necessitates rigorous public debate. This article also discusses effective risk communication approaches that play a key role in the EM risk issue. Because of uncertainty about health risks associated with EMF exposure, the public is more likely to experience difficulty in evaluating the available information and rely more on perceptions than facts when drawing conclusions. Even the most effective risk communication approaches are not likely to clarify all of the subtleties surrounding EM fields as a population health issue. Thus it is essential that all stakeholders involved in this issue participate in developing consensus solutions.

Attitude to Health↗