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At least 1,243 records · Page 69Linked to original sources
PubMed2006

[Are SPA therapy and pulsed electromagnetic field therapy effective for chronic neck pain? Randomised clinical trial. Second part: medicoeconomic approach].

UNLABELLED: We report the results of a cost-effectiveness evaluation of pulsed electromagnetic field (PEMF) therapy and spa therapy (ST) versus usual care (control) for chronic neck pain. MATERIALS AND METHODS: Inclusion criteria were age 18 to 80 years with pain in the neck area of more than 3 months' duration and no contraindications for PEMF therapy and ST. Randomization to the ST (n=25) and PEMF groups (n=26) was blinded, as was collection of data. Non-included subjects (n=29) underwent usual care. The trial respected the Helsinki declaration, and informed consent was obtained from subjects. The analysis was intent to treat; the main outcome measure was increase in health dimension scores on the MOS SF-36 in terms of increase in French health care costs from 6 months preceding to 6 months after the start of the study. RESULTS: The increase in health care costs was less for the PEMF group (+68 euro+/-539 [95% confidence interval (CI)]: -145.0+281) than the ST and control groups. The increase tended to be less, but not significantly, for the ST group (+373+/-938 euro [95% CI, -14.0+76.0]) than for controls (+618+/-2715 euro [95% CI, -434.0+167.0]). The gain of one physical MOS SF-36 unit during one year cost 3400 euro [95% CI, -6759+13 100] for the PEMF group, 29,000 euro [95% CI, -1093+59 375] for the ST group and 95076 euro [95% CI, -66 769+256 923] for the control group, but the differences were not significant. COMMENTARY: These results suggest a potential cost-effectiveness for ST and particularly PEMF as compared to usual care in chronic cervical pain. Our results perhaps lack significance probably because of lack of statistical power and do not distinguish costs related or not to chronic cervical pain.

Adult↗
PubMed2002

Electromagnetic-field distribution measurements in the soft x-ray range: full characterization of a soft x-ray laser beam.

We report direct measurement of the electromagnetic-field spatial distribution in a neonlike Ar capillary discharge-driven soft x-ray laser beam. The wave front was fully characterized in a single shot using a Shack-Hartmann diffractive optics sensor. The wave front was observed to be dependent on the discharge pressure and capillary length, as a result of beam refraction variations in the capillary plasma. The results predict approximately 70% of the laser beam energy can be focused into an area 4 times the size of the diffraction-limited spot, reaching intensities of approximately 4 x 10(13) W/cm(2).

Journal Article↗
PubMed1986

In vitro exposure to electromagnetic fields: changes in tumour cell properties.

Two human colon cancer cell lines, Colo 205 and Colo 320 DM, have been studied for their responses to 60 Hz-generated electromagnetic fields (EMF) using soft agar cloning and monoclonal antibody binding assays to assess exposure-induced changes. Cellular responses have been studied after 24 h continuous exposure of cells concurrently to four experimental conditions; i.e. no EMF (E-M-), magnetic field only (M+, 1.0 G rms), electric field only (E+, 300 mA/m2 rms), and combined electric plus magnetic fields at these intensities (E+M+). Under these conditions, both cell lines demonstrated significantly increased colony formation in soft agar and increased expression of tumor associated antigens after exposure to E+M+ and to M+ as compared to unexposed controls.

Animals↗
PubMed1989

Acute effects of ELF electromagnetic fields: a field study of linesmen working with 400 kV power lines.

The aim of the study was to investigate the possible acute effects of exposure to electric and magnetic fields. Twenty six experienced linesmen, aged 25 to 52, were studied during two working days while performing a simulated routine inspection of insulators on steel poles of a 400 kV power line. During one of the working days the inspection was performed on a power line in operation and on the other day the same procedure was performed on an identical power line, which was not in operation. The two days were found to be comparable with regard to the physical workload which, on the basis of heart rate measurements, was estimated to be high. Exposure to the electric and magnetic fields was measured using a device designed for on-worker sampling on each linesman. The mean exposure for the working day was estimated to be 2.8 kV/m (SD = 0.35) and 23.3 microT (SD = 4.2). The possible effects of exposure were studied using a battery of four automated performance tests, EEG, a mood scale, and a questionnaire to assess subjective symptoms. All workers were examined immediately before and after each workday. Furthermore, blood samples were collected for each subject on three different occasions during each workday. The battery of behavioural tests comprised a test of simple reaction time, a vigilance test, a test of short term memory (digit span), and a perceptual test (symbol digit). The four EEG recordings for each worker were judged blindly and sorted with regard to amount and stability of alpha activity. The blood samples were used for an analysis of possible changes during the workday with regard to the following hormones: thyroid stimulated hormone, luteinising hormone, follicle stimulating hormone, prolactin, cortisol, testosterone, and neopterin. Detailed analyses of the results using both parametric and nonparametric tests showed no statistically significant difference between the two conditions which could be attributed to exposure to electric and magnetic fields.

Adult↗
PubMed2007

[Are SPA therapy and pulsed electromagnetic field therapy effective for chronic neck pain? Randomised clinical trial First part: clinical evaluation].

OBJECTIVES: The purpose of this study was to compare SPA therapy (ST) with pulsed electromagnetic field (PEMF) therapy in chronic neck pain. MATERIALS AND METHODS: Inclusion criteria were age between 18 and 80 years, neck pain of more than 3 months' duration and pain score>30 mm on a visual analog scale (VAS). Exclusion criteria were contraindication to ST or PEMF. The protocol was approved by the ethics committee of Grenoble Hospital. Randomisation to the ST (n=44) and PEMF groups (n=42) was blinded. The main outcome measure was number of improved patients at 6 months in each group. A patient was considered improved if pain score decreased by more than 20%. Secondary measures were score on the Copenhagen and MOS SF-36 scales. Evaluation and intent-to-treat analysis were also blinded. RESULTS: Patients' preferences were for PEMF. At 6 months, in the PEMF group, 33 patients were improved, 5 not improved and 4 lost to follow-up. In the ST group, 24 patients were improved, 14 not improved and 6 lost to follow-up, for significantly greater improvement in the PEMF than ST group (p=0.02). Significant improvement was seen in both groups in terms of pain score, Copenhagen scale score and score on some dimensions of the MOS SF-36 survey. CONCLUSION: PEMF seems to be superior to standard ST without massage in control of neck pain. The difference between groups, although perhaps biased, seem to suggest the importance of our conclusions.

Adult↗
PubMedDate not supplied

[The effect on an impulse electromagnetic field on the bioamine allowance of the spinal ganglion in rats under whole-body exposure].

In experiments with albino male rats subjected to whole-body pulse electromagnetic irradiation of 100 mTl magnetic induction, the luminescent histochemical methods and the subsequent microspectrofluorometry were used to determine the content of biogenic amines (catecholamines, serotonin, and histamine) in spinal ganglia neurons. Significant changes were revealed not only in the content of all studied bioamines but in the histamine/serotonin ratio as well.

Animals↗
PubMed1997

Electromagnetic field exposure induces rapid, transitory heat shock factor activation in human cells.

Stimulation of human promyelocytic HL60 cells by a 60Hz magnetic field at normal growth temperatures results in heat shock factor 1 activation and heat shock element binding, a sequence of events that mediates the stress-induced transcription of the stress gene HSP70 and increased synthesis of the stress response protein hsp70kD. Thus, the events mediating the electromagnetic field-stimulated stress response appear to be similar to those reported for other physiological stresses (e.g., hyperthermia, heavy metals, oxidative stress) and could well be the general mechanism of interaction of electromagnetic fields with cells.

Binding Sites↗
PubMed1989

Effects of 50-hertz electromagnetic fields on proliferation and on chromosomal alterations in human peripheral lymphocytes untreated or pretreated with chemical mutagens.

Cultivation of human peripheral lymphocytes (HPL) in the presence of 50-Hz electromagnetic fields (EMFs) does not alter the spontaneous frequencies of sister-chromatid exchanges (SCE) and of chromosomal aberrations (CA), but leads to an enhancement of the cell cycle progression of HPLs in vitro. Pretreatment of HPLs with trenimon (TRN), diepoxybutane (DEB), or methylnitrosourea (MNU) in the G0 phase of the cell cycle results in dose-dependent elevations of the SCE frequencies. In some cases culturing of HPLs pretreated with MNU or TRN in the presence of EMFs led to significantly higher frequencies of SCEs when compared to cells cultivated in the absence of EMFs. Since we did not use multiple fixation times these data may rather result from differential influences on HPL subsets than from EMF exposure.

Alkylating Agents↗
PubMed2004

Correlation matrix of a completely polarized, statistically stationary electromagnetic field.

It is shown that, for a 3 x 3 correlation matrix Wij(r, r, omega), (i, j = x, y, z) of the electric vector of a random, stationary electromagnetic field to represent a field that is completely polarized at a point r and frequency omega, each element of the matrix must factorize. More precisely, a necessary and sufficient condition for the correlation matrix to represent a fully polarized field at a point r is that the matrix has the form Wij(r, r, omega) = epsilon(i)*(r, omega)epsilon(j)(r, omega), where epsilon(i)(r, omega) (i = x, y, z) are deterministic functions, i.e., that all pairs of the Cartesian components of the electric field at a point r and frequency omega are completely correlated.

Journal Article↗
PubMedDate not supplied

[Does a powerful electromagnetic field in the decimetric range possess genetic activity in relation to microorganisms?].

It was shown that mutants can occur in various microorganisms after a short-term exposure to electromagnetic field of 40 to 100 W/cm3 at 2375 MHz. Induction of mutants usually increases as the temperature rises and cell death rate grows to reach a maximum at a minimum survival rate. Colonial-morphological and biochemical phenotype changes are noted. Both specific and individual radiosensitivity are observed (from a 100 per cent loss of the studied character to the complete absence of the effect). Changes occur more frequently in the parameters determined by plasmids. There is a possibility to select thermoresistant variants without changing the genotype.

Bacteria↗
PubMed2003

Effect of a 902 MHz electromagnetic field emitted by mobile phones on human cognitive function: A replication study.

Our study was a replication and extension with methodological improvements to a previous study on effects of the electromagnetic field (EMF) emitted by a 902 MHz mobile phone on human cognitive functioning. Improvements on the previous study included multicentre testing and a double blind design. A total of 64 subjects (32 men and 32 women) in two independent laboratories performed a battery of 9 cognitive tasks twice: while the EMF was on and while it was off. Reaction times (RTs) and accuracy were recorded. The order of exposure and tasks was counterbalanced across subjects and gender. There were no statistically significant differences in performance between genders or laboratories. Although the RTs and the accuracy of answers were very similar to those of our previous study, our previous results were not replicated. We concluded that EMF had no effect on RTs or on the accuracy of the subjects' answers. Further, our results indicate that our EMF had no immediate effect on human cognitive functioning or that such effects are so small that they are observed on behavior only occasionally.

Adult↗