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PubMed2002

The preventive effect on bone loss of 50-Hz, 1-mT electromagnetic field in ovariectomized rats.

Osteoporosis is a common health problem, especially in the elderly and in women after menopause. Although there are some treatment methods, they impose serious side effects. Recently, the use of an electromagnetic field (EMF) has been a promising candidate for better treatment of osteoporosis. In the present study, we investigated the preventive effects of low-frequency (50 Hz), low-intensity (1 mT), and long-term (6 weeks) EMF on bone loss in ovariectomized rats. We used 18 female albino Wistar rats (8 unexposed and 10 exposed) to assess the effect of EMF. We examined the mineralization and the morphology of the tibia in control and EMF-exposed rats. The cortical thickness of the tibia was increased in EMF-exposed rats ( P < 0.002). The levels of Na and K in the tibia were significantly increased in rats exposed to EMF ( P < 0.001; P < 0.002, respectively). We also observed an increased blood alkaline phosphatase (ALP) level after EMF exposure ( P < 0.05). No significant differences in the levels of Ca, Mg, Li, or creatine were found between the exposed and unexposed groups. Our data support the notion that an EMF may prove to be an effective treatment method for osteoporosis and other abnormalities related to bone loss.

Alkaline Phosphatase↗
PubMed2004

Weak electromagnetic fields (50 Hz) elicit a stress response in human cells.

The aim of this study was to demonstrate the expression of heat shock (HS) genes in human cells in response to extremely low-frequency electromagnetic fields (ELF-EMF) alone and in combination with thermal stress. After exposing human myeloid leukemia (HL-60) cells to the stressor(s) for 30 min we quantified the expression of the HS genes HSP27, HSP60, HSP70 (A, B, and C), HSC70, HSP75, HSP78, and HSP90 (alpha and beta) by RT-PCR. The results clearly show that HS genes, in particular the three HSP70 genes (A, B, and C), are induced by ELF-EMF, a reaction that is enhanced by simultaneous HS (43 degrees C for 30 min). The results show similarities and some significant differences to previous experiments in which transgenic nematodes were used to monitor the induction of the HSP70 gene under similar stress conditions. We also studied the effect of different flux densities on gene expression in the range of 10-140 microT. Even the lowest dose tested (10 microT) resulted in a significant induction of the genes HSP70A, HSP70B, and HSP70C. The reaction to ELF-EMF shows a maximum at a flux density of 60-80 microT. The unusual dose-response relation reveals an interesting difference to other stressors that elicit the HS response.

Acute Disease↗
PubMed2002

Testicular cancer and electromagnetic fields (EMF) in the workplace: results of a population-based case-control study in Germany.

OBJECTIVES: In a population-based case-control study, we examined the association of testicular cancer and electromagnetic fields (EMF) in the workplace. METHODS: Incident cases (n = 269) were recruited between 1995 and 1997. A total of 797 controls matched on age and region were randomly selected from mandatory registries of residents. EMF exposure was assessed for five categories in standardized face-to-face interviews using closed questions. For each exposure category, odds ratios (OR) were calculated, stratified by age and region, and in a more complex model weighted by duration and distance using conditional logistic regression. Subgroup analyses were conducted for seminoma and non-seminoma and for blue- and white-collar workers. Additionally, potential radar exposure was individually assessed by experts based on all available information including free text. RESULTS: There was no excess risk for cases who reported to have ever worked near the following: radar units (OR = 1.0; 95% CI = 0.60-1.75); radiofrequency emitters (OR = 0.9; 95% CI = 0.60-1.24); electrical machines (OR = 1.0; 95% CI = 0.72-1.33): high-voltage lines or high-voltage electrical transmission installations (OR = 0.7; 95% CI = 0.38-1.18); or visual display units or complex electrical environments (OR = 0.9; 95% CI = 0.67-1.21). The results for the weighted exposure and subgroup analyses did not differ substantially. For radar exposure as assessed by the experts, the OR was 0.4 (95% CI = 0.13-1.16). CONCLUSIONS: EMF exposure in the workplace does not seem to be a relevant risk factor for testicular cancer in our study.

Adolescent↗
PubMed1997

Amyotrophic lateral sclerosis and occupational exposure to electromagnetic fields.

In an hypothesis-generating case-control study of amyotrophic lateral sclerosis, lifetime occupational histories were obtained. The patients (n = 28) were clinic based. The occupational exposure of interest in this report is electromagnetic fields (EMFs). This is the first and so far the only exposure analyzed in this study. Occupational exposure up to 2 years prior to estimated disease symptom onset was used for construction of exposure indices for cases. Controls (n = 32) were blood and nonblood relatives of cases. Occupational exposure for controls was through the same age as exposure for the corresponding cases. Twenty (71%) cases and 28 (88%) controls had at least 20 years of work experience covering the exposure period. The occupational history and task data were used to classify blindly each occupation for each subject as having high, medium/high, medium, medium/low, or low EMF exposure, based primarily on data from an earlier and unrelated study designed to obtain occupational EMF exposure information on workers in "electrical" and "nonelectrical" jobs. By using the length of time each subject spent in each occupation through the exposure period, two indices of exposure were constructed: total occupational exposure (E1) and average occupational exposure (E2). For cases and controls with at least 20 years of work experience, the odds ratio (OR) for exposure at the 75th percentile of the E1 case exposure data relative to minimum exposure was 7.5 (P < 0.02; 95% CI, 1.4-38.1) and the corresponding OR for E2 was 5.5 (P < 0.02; 95% CI, 1.3-22.5). For all cases and controls, the ORs were 2.5 (P < 0.1; 95% CI, 0.9-8.1) for E1 and 2.3 (P = 0.12; 95% CI, 0.8-6.6) for E2. This study should be considered an hypothesis-generating study. Larger studies, using incident cases and improved exposure assessment, should be undertaken.

Adult↗
PubMed1994

The effect of pulsed electromagnetic fields in the treatment of osteoarthritis of the knee and cervical spine. Report of randomized, double blind, placebo controlled trials.

OBJECTIVE: We conducted a randomized, double blind clinical trial to determine the effectiveness of pulsed electromagnetic fields (PEMF) in the treatment of osteoarthritis (OA) of the knee and cervical spine. METHODS: A controlled trial of 18 half-hour active or placebo treatments was conducted in 86 patients with OA of the knee and 81 patients with OA of the cervical spine, in which pain was evaluated using a 10 cm visual analog scale, activities of daily living using a series of questions (answered by the patient as never, sometimes, most of the time, or always), pain on passive motion (recorded as none, slight, moderate, or severe), and joint tenderness (recorded using a modified Ritchie scale). Global evaluations of improvement were made by the patient and examining physician. Evaluations were made at baseline, midway, end of treatment, and one month after completion of treatment. RESULTS: Matched pair t tests showed extremely significant changes from baseline for the treated patients in both knee and cervical spine studies at the end of treatment and the one month followup observations, whereas the changes in the placebo patients showed lesser degrees of significance at the end of treatment, and had lost significance for most variables at the one month followup. Means of the treated group of patients with OA of the knee showed greater improvement from baseline values than the placebo group by the end of treatment and at the one month followup observation. Using the 2-tailed t test, at the end of treatment the differences in the means of the 2 groups reached statistical significance for pain, pain on motion, and both the patient overall assessment and the physician global assessment. The means of the treated patients with OA of the cervical spine showed greater improvement from baseline than the placebo group for most variables at the end of treatment and one month followup observations; these differences reached statistical significance at one or more observation points for pain, pain on motion, and tenderness. CONCLUSION: PEMF has therapeutic benefit in painful OA of the knee or cervical spine.

Aged↗
PubMed2004

Electromagnetic field of extremely low frequency decreased adenylate kinase activity in retinal rod outer segment membranes.

Adenylate kinase activity in rod outer segment membranes of bovine retina decreased of about 55% when exposed to an extremely low frequency electromagnetic field of 75 Hz and 250 microT. The effect was independent of the time of permanence in the field. Negligible effects of the field were found on the enzymatic activity of a soluble isoform of adenylate kinase or of rod outer segment membranes solubilized with Triton, suggesting the importance of the membrane in determining the conditions of the enzyme inactivation.

Adenosine Triphosphate↗
PubMed1985

Healing of surgically created defects in the equine superficial digital flexor tendon: effects of pulsing electromagnetic field therapy on collagen-type transformation and tissue morphologic reorganization.

The effect of pulsing electromagnetic field (PEMF) therapy on the healing of surgically created defects in equine superficial digital flexor tendons was evaluated. Defects were created in both front superficial digital flexor tendons of 20 horses. The defect in 1 limb was exposed to a PEMF for 2 hours daily. The other limb served as a control. Histologic and immunofluorescent evaluations were done in horse killed at postsurgical weeks 2, 4, 8, 12, and 24. Therapy with the PEMF significantly (P less than 0.05) delayed the maturation of the tissue formed within the defect at postsurgical weeks 8 and 12, as determined by histologic examination. The collagen-type transformation was also delayed by the PEMF therapy, but to a degree that was not significant.

Animals↗
PubMed2006

Therapeutic effect of pulsed electromagnetic field in conservative treatment of subacromial impingement syndrome.

Subacromial impingement syndrome (SIS) is a frequent cause of shoulder pain. Our purpose in this double-blinded, randomized, and controlled study was to demonstrate whether the pulsed electromagnetic field (PEMF) provides additional benefit when used with other conservative treatment modalities in acute phase rehabilitation program of SIS. Forty-six patients with unilateral shoulder pain who had been diagnosed as having SIS were included in this trial. The cases were randomly separated into two groups. All cases received a treatment program for 3 weeks consisting of Codman's pendulum exercises and subsequent cold pack gel application on shoulders with pain 5 times a day, restriction of daily activities that require the hands to be used over the head, and meloxicam tablet 15 mg daily. One group was given PEMF; the other group was given sham PEMF daily, 25 min per session, 5 days per week for 3 weeks. Shoulder pain during rest and activity and which causes disturbance of sleep was evaluated using a visual analogue scale, and total Constant score investigated shoulder function. Daily living activities were evaluated by shoulder disability questionnaire. Results were assessed before and after treatment. When compared with the baseline values, significant improvements in all these variables were observed at the end of the treatment in both groups (p<0.05). No significant difference between treatments was observed for any of these variables (p>0.05). There is no convincing evidence that electromagnetic therapy is of additional benefit in acute phase rehabilitation program of SIS.

Activities of Daily Living↗
PubMed1993

Magnetic healing, quackery, and the debate about the health effects of electromagnetic fields.

Although the biological effects of low-frequency electromagnetic radiation have been studied since the time of Paracelsus, there is still no consensus on whether these effects are physiologically significant. The recent discovery of deposits of magnetite within the human brain as well as recent, highly publicized tort litigation charging adverse effects after exposure to magnetic fields has rekindled the debate. New data suggest that electromagnetic radiation generated from power lines may lead to physiologic effects with potentially dangerous results. Whether these effects are important enough to produce major epidemiologic consequences remains to be established. The assumption of quackery that has attended this subject since the time of Mesmer's original "animal magnetism" investigations continues to hamper efforts to compile a reliable data base on the health effects of electromagnetic fields.

Adult↗
PubMed1991

Effect of pulsed electromagnetic field on healing of experimental nonunion in rat tibiae.

To see the effect of Pulsed Electromagnetic Field (PEMF) on nonunited fracture healing, nonunion was induced in rat tibiae and PEMF was applied on it. Out of five different techniques utilised for inducing nonunion soft tissue interposition was found to be the most suitable and effective method of experimental induction of nonunion. Twenty eight experimental and 15 control rats were finally evaluated for the effect of PEMF applied for up to 8 weeks. After sacrifice of 8 experimental and 4 controls, 6 experimental and 3 controls, again 6 experimental and 3 controls and finally 8 experimental and 5 controls at 2, 4, 6 and 8 weeks respectively of PEMF application no significant difference as to the quality of healing was observed between the experimental and control animals. It was thus concluded that PEMF appeared to have no beneficial effect on the healing of nonunited fractures in experimental set-up.

Animals↗
PubMed2001

Biological processes, quantum mechanics and electromagnetic fields: the possibility of device-encapsulated human intention in medical therapies.

The general hypothesis that quantum mechanics (QM) and thermodynamic concepts relate to biological systems is discussed and applied to the biological influence of: (1) electromagnetic fields (EMFs); and (2) EMFs that have been exposed to human intention. We illustrate our hypothesis with experiments involving four simultaneous treatments: exposure to ambient EMFs in the laboratory environment (C), exposure in a Faraday cage (F) and exposure in a Faraday cage with either: (i) an electronic device (IIED) which had been exposed to a specific human intention (d,j); or (ii) a non-exposed, physically identical, device (d,o). Experimental systems were fitness and energy metabolism in Drosophila melanogaster, in vitro enzyme activity and molecular concentration variability over time. Results indicated that shielding from ambient EMFs via a Faraday cage (F) made a significant difference relative to the unshielded control (C). Further, (d,o) had a significant lowering effect in the shielded environment. Finally, there was a strong 'intention' effect with the IIED (d,j) producing significant and positive effects in comparison to (d,o) in each experimental system.

Adenosine Diphosphate↗
PubMed1996

Resolution of partial cataplexy in multiple sclerosis by treatment with weak electromagnetic fields.

Cataplexy, an ancillary symptom of narcolepsy, involves the sudden loss of muscle tone without altered consciousness usually brought on by sudden excitement or emotional influence and extreme exertions (Guilleminault et al., 1974; Parks et al., 1974; Guilleminault, 1976; Aldrich, 1992; 1993; Scrima, 1981; Baker, 1985). Attacks of generalized cataplexy produce complete atonic, areflexic partial or complete paralysis of striated muscles commonly involving the leg muscles resulting in collapse of the knees and falling while milder forms often termed partial cataplexy may manifest by sagging of the face, eyelid, or jaw, dysarthria, blurred vision, drooping of the head, weakness of an arm or leg, buckling at the knees, or simply a momentary sensation of weakness that is imperceptible to observers (Guilleminault, 1976; Aldrich, 1993). The duration of cataplexy is usually a few seconds, although severe episodes can last several minutes and rarely several hours or days in the case of "status cataplecticus" (Parkes et al., 1974; Guilleminault, 1976; Billiard & Cadilhac, 1985; Aldrich, 1992; 1993). This report concerns a 51 year old man with chronic progressive multiple sclerosis who exhibited daily episodes of partial cataplexy which resolved within 3 weeks after he received treatment with picotesla electromagnetic fields.

Brain↗
PubMed1984

Pulsed electromagnetic field therapy of persistent rotator cuff tendinitis. A double-blind controlled assessment.

The value of pulsed electromagnetic fields (PEMF) for the treatment of persistent rotator cuff tendinitis was tested in a double-blind controlled study in 29 patients whose symptoms were refractory to steroid injection and other conventional conservative measures. The treated group (15 patients) had a significant benefit compared with the control group (14 patients) during the first 4 weeks of the study, when the control group received a placebo. In the second 4 weeks, when all patients were on active coils, no significant differences were noted between the groups. This lack of difference persisted over the third phase, when neither group received any treatment for 8 weeks. At the end of the study 19 (65%) of the 29 patients were symptomless and 5 others much improved. PEMF therapy may thus be useful in the treatment of severe and persistent rotator cuff and possibly other chronic tendon lesions.

Clinical Trials as Topic↗
PubMed1999

Industrialization, electromagnetic fields, and breast cancer risk.

The disparity between the rates of breast cancer in industrialized and less-industrialized regions has led to many hypotheses, including the theory that exposure to light-at-night and/or electromagnetic fields (EMF) may suppress melatonin and that reduced melatonin may increase the risk of breast cancer. In this comprehensive review we consider strengths and weaknesses of more than 35 residential and occupational epidemiologic studies that investigated the association between EMF and breast cancer. Although most of the epidemiologic data do not provide strong support for an association between EMF and breast cancer, because of the limited statistical power as well as the possibility of misclassification and bias present in much of the existing data, it is not possible to rule out a relationship between EMF and breast cancer. We make several specific recommendations for future studies carefully designed to test the melatonin-breast cancer and EMF-breast cancer hypotheses. Future study designs should have sufficient statistical power to detect small to moderate associations; include comprehensive exposure assessments that estimate residential and occupational exposures, including shift work; focus on a relevant time period; control for known breast cancer risks; and pay careful attention to menopausal and estrogen receptor status.

Breast Neoplasms↗
PubMedDate not supplied

Treatment of nonuniting osteotomies with pulsating electromagnetic fields. A controlled animal experiment.

To evaluate treatment of nonunions or pseudarthrosis in humans by pulsating electromagnetic fields (PEMF), the authors tested the method in four- to six-year-old beagle dogs with midshaft osteotomies of both ulnae. This type of osteotomy in dogs leads to nonunion. After surgery one foreleg of each dog was stimulated for an average of 25 days; the second foreleg served as a control. Subsequently all ulnae were harvested, radiographs were obtained, and the stiffness of the callus was mechanically tested. Thus, the reputed efficiency is not confirmed by controlled experiments on dogs. The stimulated bones were neither radiologically nor mechanically superior to the controls.

Animals↗
PubMed2004

Electromagnetic fields around silver nanoparticles and dimers.

We use the discrete dipole approximation to investigate the electromagnetic fields induced by optical excitation of localized surface plasmon resonances of silver nanoparticles, including monomers and dimers, with emphasis on what size, shape, and arrangement leads to the largest local electric field (E-field) enhancement near the particle surfaces. The results are used to determine what conditions are most favorable for producing enhancements large enough to observe single molecule surface enhanced Raman spectroscopy. Most of the calculations refer to triangular prisms, which exhibit distinct dipole and quadrupole resonances that can easily be controlled by varying particle size. In addition, for the dimer calculations we study the influence of dimer separation and orientation, especially for dimers that are separated by a few nanometers. We find that the largest /E/2 values for dimers are about a factor of 10 larger than those for all the monomers examined. For all particles and particle orientations, the plasmon resonances which lead to the largest E-fields are those with the longest wavelength dipolar excitation. The spacing of the particles in the dimer plays a crucial role, and we find that the spacing needed to achieve a given /E/2 is proportional to nanoparticle size for particles below 100 nm in size. Particle shape and curvature are of lesser importance, with a head to tail configuration of two triangles giving enhanced fields comparable to head to head, or rounded head to tail. The largest /E/2 values we have calculated for spacings of 2 nm or more is approximately 10(5).

Journal Article↗
PubMed1984

[Evaluation of maximum permissible intensity of electromagnetic fields].

E-m fields and radiation in natural environment are characterized by the ratio of vectors: E:H = 120 II omega. For technological purposes a specific ratio of U:I in circuits is set, which imposes a change in the E:H ratio in the e-m being dispersed. It has been suggested that under the allowable intensities of e-m fields at workplaces the E:H = 120 II omega ratio be maintained. Critically evaluated were presently mandatory allowable values of e-m fields, inconsistensies of protective zones and irrationality of the E:H ratio being enhanced. Basing on analysis of results of studies on biological effects of e-m fields and verified standards GOST 12.1.006-76 1982 and ANSI C.95.1 1982, a draft project of allowable intensities of e-m fields has been submitted, distinguishing between general exposure related to general population and professional exposure related to those working in e-m fields exposure. Maximum values of e-m fields, differentiated in the frequency function are characterized by the ratio E:H = = 120 II omega and relate to workplaces and other places where people may stay. Furthermore, additional guidelines reducing the risk of e-m fields exposure have been presented.

Electromagnetic Fields↗
PubMed2003

Electromagnetic fields and breast cancer on Long Island: a case-control study.

The EMF and Breast Cancer on Long Island Study (EBCLIS) was a case-control study designed to evaluate the possible association between exposure to electromagnetic fields (EMFs) and breast cancer. Eligible women were participants in the population-based Long Island Breast Cancer Study Project, were under 75 years of age at enrollment, were residentially stable, and were identified between August 1, 1996, and June 20, 1997. Of those eligible, 576 cases and 585 controls participated in EBCLIS (87% and 83%, respectively). In-home data collection included various spot and 24-hour EMF measurements, ground-current magnetic field measurements, wire mapping of overhead power lines servicing the home, and an interview. Odds ratios and 95% confidence intervals were based on multivariate logistic regression analyses. All odds ratios were close to 1 and nonsignificant. For the highest quartile of 24-hour EMF measurements, the odds ratio was 0.97 (95% confidence interval (CI): 0.69, 1.37) in the bedroom and 1.09 (95% CI: 0.78, 1.51) in the most lived-in room. For the highest exposure category of ground-current measurements, the odds ratio was 1.13 (95% CI: 0.88, 1.44) in the bedroom and 1.08 (95% CI: 0.85, 1.38) in the most lived-in room. These and other EBCLIS results agree with other recent reports of no association between breast cancer and residential EMF exposures.

Adult↗