bluuebunny/crossref_metadata_2025_split huggingface dataset:
Astrocytoma risk related to job exposure to electric and magnetic fields
Authors: Mack Wendy , Preston‐Martin Susan , Peters John M. 
Published: February 2006

AbstractTo investigate the association between occupational exposure to low‐frequency electric and magnetic (EM) fields and risk of brain tumors, a study was performed in Los Angeles County on 272 male adults with primary intracranial gliomas or meningiomas and 272 neighborhood controls. Complete occupational histories were collected. Risk associated with employment for more than 10 years in jobs that are presumed to entail exposure to EM fields was computed for various histological groupings. A nonsignificantly elevated risk of 1.7 was found for gliomas (all types pooled: 95% confidence interval 0.7–4.4), and a nonsignificantly reduced risk of 0.3 (95% confidence interval 0.03–3.2) was found for meningiomas. For astrocytomas, which form a subtype of the gliomas, a significantly elevated risk of 10.3 (95% confidence interval 1.3–80.8) was found; a significant upward trend (P = .01) of tumor incidence with increasing length of employment was observed. Most astrocytoma patients who worked in occupations involving exposure to EM fields were electricians or electrical engineers.
Ouabain inhibition of kidney ATPase is altered by 9.14 GHz radiation
Authors: Brown H. D. , Chattopadhyay S. K. 
Published: February 2006

AbstractAt each of several stabilized temperatures between 7.0 and 43.8 °C, increases in dog‐kidney, Na+ −, K+‐ATPase catalytic activity were usually observed in association with exposure for 5 min to 9.14 GHz CW microwave radiation in a thin tubular reactor. However, at 24.9 °C, a 23% decrease occurred. Comparisons of activity of ouabain‐inhibited reactions revealed that the efficacy of the cardiac glycoside as an inhibitor of ATPase activity was severely diminished by the microwave field. The ouabain‐site control mechanism may be a specific microwave target at this exposure frequency. Experimental results can be interpreted in terms of molecular structural changes or direct energy input. The estimated SAR of energy that was incident on preparations is 20 W/kg.
Calcium uptake by leukemic and normal T‐lymphocytes exposed to low frequency magnetic fields
Authors: Lyle Daniel B. , Wang Xinghua , Ayotte Robert D. , Sheppard Asher R. , Adey W. Ross 
Published: February 2006

AbstractCalcium‐ion uptake by normal and leukemia lymphocytes increased during a 30‐min exposure to a 13.6 Hz, sinusoidal magnetic field at 20 μT peak. The time‐varying field was horizontal and parallel to a 16.5 μT component of the ambient static magnetic field. The uptake of 45Ca2+ increased 102% in a line of murine, cytotoxic T‐lymphocytes (C57B1/6‐derived CTLL‐1), increased 126% in freshly‐isolated spleen lymphocytes (C57B1/6 mice), and increased 75% in a line of lymphoma cells (C57B1/6‐derived EL4). In contrast, there was no effect when the same field was applied for 30 min immediately before—as opposed to during—incorporation of calcium ions. When spleen lymphocytes were exposed during incubation with 45Ca2+ to a 60 Hz magnetic field at 20 μT peak, a small but statistically significant increase (37%) in uptake of the labeled ions occurred. These results indicate that weak, alternating magnetic fields might affect calcium‐dependent functions of normal and leukemic lymphocytes.
Millimeter‐wave effects on electric activity of crayfish stretch receptors
Authors: Khramov R. N. , Sosunov E. A. , Koltun S. V. , Ilyasova E. N. , Lednev V. V. 
Published: February 2006

AbstractThe effects of super high frequency (SHF) microwaves (34–78 GHz) on rates of spontaneous firing of the slowly adapting, stretch‐receptor neurons of crayfish were studied. Initially, irradiation of continuously perfused, fluid‐cooled preparations at power densities to 250 mW/cm2 caused a transient decrease in the rate of spontaneous firing (the dynamic response). Subsequently, with extinction of the SHF field, the rate of firing increased, finally stabilizing at pre‐exposure levels (stationary phase). Rates of firing also increased when the receptor muscle was stretched, and they were inversely correlated with small, field‐induced increases of temperature (∼1.5°C). The response to SHF radiation did not depend on frequency if temperature of the medium was constant. No resonant peaks were found when the millimeter range of frequencies was scanned.
Cancer promotion in a mouse‐skin model by a 60‐Hz magnetic field: II. Tumor development and immune response
Authors: McLean Jack R. N. , Stuchly Maria A. , Mitchel Ronald E. J. , Wilkinson Diana , Yang H. , Goddard Michael , Lecuyer David W. , Schunk Michael , Callary Eva , Morrison David 
Published: February 2006

AbstractThis paper describes preliminary findings on the influence of 60‐Hz (2‐mT) magnetic fields on tumor promotion and co‐promotion in the skins of mice. The effect of magnetic fields on natural killer (NK) cell activity in spleen and blood was also examined. Groups of 32 juvenile female mice were exposed to the magnetic field as described in part I. The dorsal skin of all animals was treated with a subthreshold dose of the carcinogen 7, 12‐dimethylbenz(a)anthracene (DMBA). One week after the treatment, two groups were sham exposed (group A) or field exposed at 2 mT (group B) 6 h/day for 21 weeks, to test whether the field would act as a tumor promoter. No tumors developed in these two groups of mice. To test whether the magnetic field would modify tumor development by directly affecting tumor growth or by suppressing immune surveillance, two additional groups of mice were treated weekly with the tumor promoter 12–0‐tetradecanoylphorbol‐13‐acetate (TPA) and then either sham exposed (group C) or field exposed (group D). The time to appearance of tumors was shorter (but not statistically so) in the group exposed to magnetic fields and TPA. Some differences in NK cell activity and spleen size were observed between the sham‐ and field‐exposed groups.
Transcription in Drosophila melanogaster salivary gland cells is altered following exposure to low‐frequency electromagnetic fields: Analysis of chromosome 3R
Authors: Goodman Reba , Weisbrot David , Uluc Alun , Henderson Ann 
Published: February 2006

AbstractThe use of the transcription autoradiographic method permits identification of nascent RNA chains directly on identifiable regions of Drosophila salivary gland chromosomes. Changes in transcriptional activity at 13 defined regions of the right arm of chromosome 3 (3R) were observed following 20‐min exposures of salivary glands to five different extremely low frequency (ELF) electromagnetic (EM) fields. Changes in translational patterns were also induced by the ELF EM fields in exposed cells. Differences included an increase in over‐all polypeptide synthesis as well as in the number of polypeptides resolved in cells exposed to EM fields. © 1992 Wiley‐Liss, Inc.
An analysis of associations between social class and ambient magnetic fields in metropolitan melbourne
Authors: Salzberg M. R. , Farish S. J. , Delpizzo Vincent 
Published: February 2006

AbstractIn the course of a study on residential magnetic‐field exposure, some incidental data were obtained that bear on the issue of confounding of magnetic field exposure by social class. We have explored the possibility that the magnetic flux density of 50 Hz fields measured in Melbourne streets is correlated with a number of variables that index the socio‐economic status of the neighborhood. We have examined also for a correlation between field‐intensity levels and sums of some or all of the indicators, which were weighted to provide an overall score on socio‐economic status. Although some of the indexes were weakly, but significantly, correlated with environmental levels of magnetic fields, the combined indices were not. These results indicate that socio‐economic status is not likely to be a confounder in epidemiological studies of residential exposure to ELF magnetic fields in Melbourne. © 1992 Wiley‐Liss, Inc.
An integrated ELF magnetic‐field generator and incubator for long‐term in vitro studies
Authors: Jones Robert A. , Sheppard Asher R. 
Published: February 2006

AbstractLong‐term studies of the effects of low‐frequency magnetic fields on cells in culture require an incubator that is free of contaminating magnetic fields and that provides automatic control of exposure duration, uniform applied fields, a uniform and well‐controlled environmental temperature, and high reliability of the total system. We describe a dual‐incubator system in which the enclosed solenoid of either unit can provide a sham exposure while the other generates a magnetic induction of up to 500 μT. Each solenoid‐incubator unit contains an enclosed rack that can hold as many as 140 petri dishes for culturing cells; each unit is heated radiantly by circulating warm water. Field‐exposure conditions and temperatures are continuously monitored and controlled by a microcomputer. © 1992 Wiley‐Liss, Inc.
Alternative functional relationships between ELF field exposure and possible health effects: Report on an expert workshop
Authors: Morgan M. Granger , Nair Indira 
Published: February 2006

AbstractIf exposure to 60 Hz fields poses risks to public health, the relationship between exposure and risk may involve something other than the product of field strength and time. Such alternative possible relations, or “effects functions,” are of great interest to epidemiologists, engineers, risk analysts, and regulators. A structured survey and workshop were used to explore whether leading researchers in bioelectromagnetics share similar views about alternative possible effects functions. Substantial agreement was found about several effects functions in a few specific contexts such as calcium‐ion efflux and cell signaling, and biosynthesis pathways. No significant agreement emerged in many other contexts. No effects function possibilities were ruled out. Further effort of this sort was judged unlikely to yield greater consensus until more complete scientific understanding becomes available. However, a series of structured workshops on research planning and priority setting were judged to hold great potential for useful results. 1992 Wiley‐Liss, Inc.
Rats are not aversive when exposed to 60‐Hz magnetic fields at 3.03 mT
Authors: Lovely R. H. , Creim J. A. , Kaune W. T. , Miller M. C. , Phillips R. D. , Anderson L. E. 
Published: February 2006

AbstractThirty‐two male rats were tested in two replicates of an experiment to determine whether body currents induced by 60‐Hz magnetic fields might lead to avoidance behavior comparable to that which results from exposure to strong 60‐Hz electric fields. The test apparatus was a two‐compartment Plexiglas® shuttlebox enclosed in a sound‐attenuating plywood chamber, which in turn was encompassed by two copper bus bars that, when energized, served as a source of 60‐Hz magnetic fields. Location of the rat, and traverse activity in the shuttlebox were monitored by nine infra‐red photo detectors equally spaced along the length of the apparatus. Rats were divided into 2 groups: 1 group of rats (n = 8 per group per replicate) was sham exposed while rats in the other group (n = 8 per group per replicate) were exposed to a 3.03 mT (30.3 G), 60‐Hz magnetic field whenever they traversed to or were located on the side (L or R) predetermined as the exposed side. To control artifact incident to side preference, the side exposed (L or R) was alternated over the exposed rats. Each rat was tested individually in a 1‐h session. A 2‐factor ANOVA (exposed vs. control, replicate 1 vs. replicate 2) failed to reveal any significant effects due to either factor or to an interaction between factors. These data demonstrate that rats do not avoid exposure to 60‐Hz magnetic fields at a flux density of 3.03 mT and further imply that the avoidance by rats of high level 60‐Hz electric fields is mediated by something other than the internal body currents induced by the exposure. 1992 Wiley‐Liss, Inc.
Effects of 45‐Hz magnetic fields on the functional state of the human brain
Authors: Lyskov Evgeny B. , Juutilainen Jukka , Jousmäki Veikko , Partanen Juhani , Medvedev Sviatoslav , Hänninen Osmo 
Published: February 2006

AbstractThe influence of sinusoidal 45‐Hz magnetic fields on the brain functions of 20 volunteers was investigated in a double‐blind study using spectral analysis of EEG and measurements of Omega potentials and reaction time (RT). The field strength was 1,000 A/m (1.26 mT) and the duration of exposure was 1 h. Ten volunteers were exposed to a continuous field and ten received an intermittent exposure (1 s on/1 s off). Each person received one real and one sham exposure. One half of the volunteers got the real exposure first and the sham treatment after at least 24 h. For the rest, the sequence was inverse. The measurements of EEG, omega potentials and RT were performed before and after each exposure. Several statistically significant changes were observed, most of them after intermittent exposure. In the EEG, an increase of alpha (7.6–13.9 Hz) activity and a decrease of delta (1.5–3.9 Hz) activity were observed. β waves (14.2–20 Hz) increased in the frontal derivations as did the total power in occipital derivations. The mean and peak frequencies of EEG increased mainly in the frontal derivations. No direct effects on RT were seen. Learning to perform the RT test (decrease of RT in repeated trials), however, seemed to be affected by the exposure. The persons who received real exposure first learned more slowly than those who got sham exposure first. Further experiments are necessary to confirm the findings and for understanding the mechanisms of the effects. © 1993 Wiley‐Liss. Inc.
Misclassification of ELF occupational exposure resulting from spatial variation of the magnetic field
Authors: Delpizzo Vincent 
Published: February 2006

AbstractThe adequacy of a single hip‐ or chest‐worn magnetic field dosimeter to reliably classify subjects with respect to their occupational ELF magnetic field exposure is investigated. Hip‐worn dosimeters consistently underestimate both whole‐body average exposure and head exposure, tentatively regarded here as two possible definitions of the “true” exposure measurement. The approximate resulting bias in the relative risk estimate in hypothetical case‐control studies is evaluated. A chest‐worn dosimeter is found to be generally superior to a hip‐worn one in assessing exposure during the occupational tasks considered here. © 1993 Wiley‐Liss. Inc.
Design and characterization of a system for exposure of cultured cells to extremely low frequency electric and magnetic fields over a wide range of field strengths
Authors: Mullins Roland D. , Sisken Jesse E. , Hejase Hassan A. N. , Sisken Betty F. 
Published: February 2006

AbstractA system is described that is capable of producing extremely low frequency (ELF) magnetic fields for relatively short‐term exposure of cultured mammalian cells. The system utilizes a ferromagnetic core to contain and direct the magnetic field of a 1,000 turn solenoidal coil and can produce a range of flux densities and induced electric fields much higher than those produced by Helmholtz coils. The system can generate magnetic fields from the microtesla (μT) range up to 0.14 T with induced electric field strengths on the order of 1.0 V/m. The induced electric field can be accurately varied by changing the sample chamber configuration without changing the exposure magnetic field. This gives the system the ability to separate the bioeffects of magnetic and induced electric fields. In the frequency range of 4–100 Hz and magnetic flux density range of 0.005–0.14 T, the maximum total harmonic distortion of the induced electric field is typically less than 1.0%. The temperature of the samples is held constant to within 0.4°C by constant perfusion of warmed culture medium through the sample chamber. © 1993 Wiley‐Liss, Inc.
Action of 50 Hz magnetic fields on neurite outgrowth in pheochromocytoma cells
Authors: Blackman C. F. , Benane S. G. , House D. E. , Pollock M. M. 
Published: February 2006

AbstractThis study tests the capacity of 50 Hz magnetic and electric fields to stimulate neurite outgrowth in PC‐12D cells, a cell line which originated from a pheochromocytoma in rat adrenal medulla. The cells were plated on collagen‐coated, plastic petri dishes and exposed to sinusoidal 50 Hz magnetic fields for 22 h in a 5% CO2 incubator at 37°C. Two 1,000 turn coils, 20 cm in diameter, were assembled in a Helmholtz configuration to generate a magnetic field in a vertical orientation, thereby inducing a companion electric field in the dish with intensity proportional to radius. A magnetic‐field shield housed the control samples in the same incubator. Total cells and number of cells with neurites at least as long as one cell diameter or having a growth cone were counted within a radius of 0.3 cm of the dish center and within an annulus of 1.7–1.8 cm radii in 60 mm dishes, at 3.6 cm radius in 100 mm dishes, and between 1.9 and 2.1 cm radii in the outer well of organ culture dishes, which are physically separated into two concentric wells. Sham exposure demonstrated no difference in percentage of cells with neurites between the exposed and control locations in the incubator. Exposures were done at 4.0. 8.9, 22, 29, 40, 120, 236, and 400 milliGauss (mG). At dish radii of 1.7–1.8 cm in the 60 mm dishes these magnetic flux densities induced electric fields of 1.1, 2.5, 5.9, 8.1, 11, 33, 65, and 110 μV/m, respectively, while within a radius of 0.3 cm, the induced electric fields were less than 0.2, 0.4, 1.0, 1.5, 1.9, 6.0, 11, and 19 μV/m, respectively. For other dishes, the larger radii produced proportionally larger induced electric fields. At each field strength, there were two control dishes and four to nine exposed dishes: 100 or more cells were counted at each location on the dishes. The results demonstrate that magnetic fields stimulate neurite outgrowth in a flux‐density‐dependent manner between 22 and 40 mG, reaching an apparent stimulation plateau between 40 and 400 mG; no effects were seen at 8.9 mG or lower. There was no apparent neurite stimulation due to the electric field. Although relatively low intensity (≫22mG) magnetic fields alone can stimulate a morphological response in a cell which is normally stimulated by nerve growth factor molecules binding to membrane receptors, the chemical basis of this response is unknown. © 1993 Wiley‐Liss. Inc.
Influence of 50 Hz electric and magnetic fields on the human heart
Authors: Korpinen L. , Partanen J. , Uusitalo A. 
Published: February 2006

AbstractThis investigation studied the effect of 50 Hz electric and magnetic fields on the human heart. The electrocardiograms of 27 transmission‐line workers and 26 male volunteers were recorded with a Holter recorder both in and outside the fields. The measurements took from half an hour to a few hours. The electric field strength varied from 0.14 to 10.21 kV/m and the magnetic flux density from 1.02 to 15.43 μT.Analysis of the ECG recordings showed that extrasystoles or arrhythmias were as frequent outside the field as in the field. In some cases a small decrease in heart rate was observed after field exposure. © 1993 Wiley‐Liss, Inc.
Pretreatment of rats with pulsed electromagnetic fields enhances regeneration of the sciatic nerve
Authors: Kanje Martin , Rusovan Ana , Sisken Betty , Lundborg Göran 
Published: February 2006

AbstractRegeneration of the sciatic nerve was studied in rats pretreated in a pulsed electromagnetic field (PEMF). The rats were exposed between a pair of Helmholtz coils at a pulse repetition rate of 2 pps at a field density of 60 or 300 μT. The PEMF treatment was then discontinued. After an interval of recovery, regeneration of the sciatic nerve was initiated by a crush lesion. Regeneration of sensory fibers was measured by the “pinch test” after an additional 3–6 days. A variety of PEMF pretreatments including 4 h /day for 1–4 days or exposure for 15 min/day during 2 days resulted in an increased regeneration distance, measured 3 days after the crush lesion. This effect could be demonstrated even after a 14‐day recovery period. In contrast, pretreatment for 4 h/day for 2 days at 60 μT did not affect the regeneration distance. The results showed that PEMF pretreatment conditioned the rat sciatic nerve in a manner similar to that which occurs after a crush lesion, which indicates that PEMF affects the neuronal cell body. However, the mechanism of this effect remains obscure. © 1993 Wiley‐Liss, Inc.
Influence of weak static and 50 Hz magnetic fields on the redox activity of cytochrome‐C oxidase
Authors: Nossol Bruno , Buse Gerhard , Silny Jiri 
Published: February 2006

AbstractThe effects of static and 50 Hz magnetic fields on cytochrome‐C oxidase activity were investigated in vitro by strictly controlled, simultaneous polarographic measurements of the enzyme's high‐ and low‐affinity redox reaction. Cytochrome‐C oxidase was isolated from beef heart. Control experiments were carried out in the ambient geomagnetic and 50 Hz magnetic fields at respective flux densities of 45 and 1.8 μT. The experimentally applied fields, static and time‐varying, were generated by Helmholtz coils at flux densities between 50 μT and 100 mT. Exposures were timed to act either on the combined enzyme‐substrate interchange or directly on the enzyme's electron and proton translo‐cations. Significant changes as high as 90% of the overall cytochrome‐C oxidase activity resulted during exposure (1) to a static magnetic field at 300 μT or 10 mT in the high‐affinity range, and (2) to a 50 Hz magnetic field at 10 or 50 mT in the low‐affinity range. No changes were observed at other flux densities. After exposure to a change‐inducing, static or time‐varying field, normal activity returned. © 1993 Wiley‐Liss. Inc.
Synergistic effects of ionizing radiation and 60 Hz magnetic fields
Authors: Hintenlang David E. 
Published: February 2006

AbstractExperiments designed to evaluate the synergistic production of clastogenic effects by ionizing radiation and 60 Hz magnetic fields were performed using human lymphocytes from peripheral blood. Following exposure to ionizing radiation, cells were cultured in 60 Hz magnetic fields having field strengths up to 1.4 mT. Cells exposed to both ionizing radiation and 60 Hz magnetic fields demonstrated an enhanced frequency of near tetraploid chromosome complements, a feature not observed following exposure to only ionizing radiation. The results are discussed in the context of a multiple‐stage model of cellular transformation, employing both initiating and promoting agents. © 1993 Wiley‐Liss. Inc.
Effect of electromagnetic stimulation with different waveforms on cultured chick tendon fibroblasts
Authors: Guzelsu N. , Salkind A. J. , Shen X. , Patel U. , Thaler S. , Berg R. A. 
Published: February 2006

AbstractAn energy efficient electromagnetic stimulator device for fracture healing was compared to a commercially available device in stimulating cell growth in tissue cultures. The energy efficient device, which conserves energy by using a bidirectional time‐dependent magnetic wave form, and the commercially available stimulator, which uses a unidirectionaltime‐dependent magnetic wave form, were tested on chick tendon fibroblasts in primary culture. Comparing non‐stimulated control and cells electromagnetically stimulated with unidirectional and bidirectional waveforms showed that at the growth phase between days 2 and 3, both electrical stimulation techniques increased cell division as measured by DNA synthesis. When cells were dividing rapidly, collagen synthesis was reduced. When the cells reached the confluence there was no difference among the groups (control, unidirectionally stimulated, and bidirectionally stimulated) in terms of number of cells or collagen produced. © 1994 Wiley‐Liss, Inc.