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Shielding the First 24 Postnatal Months of Life: A Proposal for a Prospective Cohort Study of Early-Life Electromagnetic Exposure and Autism Risk.

BACKGROUND: Autism Spectrum Disorder (ASD) involves Mirror Neuron System (MNS) dysfunction, driving core social and imitative impairments. Systemic physiological alterations such as autonomic dysregulation, mitochondrial dysfunction and neuroinflammation are known to impair synchronization and plasticity of neuronal clusters. A less-evident environmental cofactor, coinciding with rising ASD prevalence, is the considerable world-wide increase in electromagnetic radiation (EMR) overall exposure among children. Experimental evidence shows how low-intensity EMR influences cellular processes, via voltage-gated calcium channels (VGCCs), oxidative stress, and mitochondrial metabolism. The Resonant Convergence framework, allow to predict how chronic EMR exposure during the first 24 postnatal months of life can act as a factor in ASD pathogenesis. The best candidate mechanism is chronic Ion Cyclotron Resonance (ICR) detuning the Ca2+-calmodulin pathway, thus disrupting MNS synchronization. METHODS AND ANALYSIS: A prospective observational pilot cohort study (24-month follow-up) proposes to enroll 1000 full-term newborns into two arms: an EMR-reduced cohort (n = 500, rest and sleep-phase Faraday shielding) and a standard exposure cohort (n = 500). Exposure is quantified via radiofrequency (RF)/extremely low frequency(ELF) measurements, proximity analysis, device inventories and wearable dosimetry. The primary endpoint is a continuous neurodevelopmental trajectory score (joint attention, language, electroencephalogram (EEG) mu-rhythm); binary ASD diagnosis (Autism Diagnostic Observation Schedule, Second Edition (ADOS-2), Autism Diagnostic Interview-Revised (ADI-R)) is a secondary, exploratory endpoint. Moreover, an optional genomic screening will evaluate gene-environment interactions within extremely low-frequency electromagnetic field (ELF-EMF) vulnerable pathways, including ASD-associated genes upregulated by RF via bromodomain and extraterminal protein (BET)-mediated epigenetic mechanisms. Analyses will employ risk ratios, Fisher's exact tests and logistic regression adjusted for confounders; mixed-effects and Bayesian modeling will evaluate longitudinal outcomes and exposure reduction effects. Given a 2-3% baseline prevalence, approximately 20-30 ASD cases are expected. The study is therefore powered for exploratory signal detection rather than definitive causal inference, providing the critical baseline data required to justify and design future confirmatory trials. Sex-stratified modeling will address the 4:1 male-to-female prevalence ratio. ETHICS AND DISSEMINATION: Ethics committee approval is not yet sought; full protocol review and approval will be obtained prior to the study initiation, in strict accordance with the Declaration of Helsinki. Written parental informed consent will be mandatory for all participants prior to enrollment. Study findings and methodological milestones will be disseminated through peer-reviewed international scientific publications. This protocol provides a structured methodological framework for the first prospective investigation of sleep-phase EMR reduction as a potential modulator of ASD incidence during early neurodevelopment. Results will inform adequately powered confirmatory trials in electromagnetic neurodevelopmental epidemiology.

autism spectrum disorder↗

A comparison of various "housekeeping" probes for northern analysis of normal and osteoarthritic articular cartilage RNA.

Several approaches are commonly used to normalize variations in RNA loading on Northern blots, including: ethidium bromide (EthBr) fluorescence of 18S or 28S rRNA or autoradiograms of radioactive probes hybridized with constitutively expressed RNAs such as elongation factor-1alpha (ELF), glyceraldehyde-3-phosphate dehydrogenase (G3PDH), actin, 18S or 28S rRNA, or others. However, in osteoarthritis (OA) the amount of total RNA changes significantly and none of these RNAs has been clearly demonstrated to be expressed at a constant level, so it is unclear if any of these approaches can be used reliably for normalizing RNA extracted from osteoarthritic cartilage. Total RNA was extracted from normal and osteoarthritic cartilage and assessed by EthBr fluorescence. RNA was then transferred to a nylon membrane hybridized with radioactive probes for ELF, G3PDH, Max, actin, and an oligo-dT probe. The autoradiographic signal across the six lanes of a gel was quantified by scanning densitometry. When compared on the basis of total RNA, the coefficient of variation was lowest for 28S ethidium bromide fluorescence and oligo-dT (approximately 7%), followed by 18S ethidium bromide fluorescence and G3PDH (approximately 13%). When these values were normalized to DNA concentration, the coefficient of variation exceeded 50% for all signals. Total RNA and the signals for 18S, 28S rRNA, and oligo-dT all correlated highly. These data indicate that osteoarthritic chondrocytes express similar ratios of mRNA to rRNA and mRNA to total RNA as do normal chondrocytes. Of all the "housekeeping" probes, G3PDH correlated best with the measurements of RNA. All of these "housekeeping" probes are expressed at greater levels by osteoarthritic chondrocytes when compared with normal chondrocytes. Thus, while G3PDH is satisfactory for evaluating the amount of RNA loaded, its level of expression is not the same in normal and osteoarthritic chondrocytes.

Actins↗

Chronic or intractable medical problems associated with prolonged exposure to unsuspected harmful environmental electric, magnetic or electro-magnetic fields radiating in the bedroom or workplace and their exacerbation by intake of harmful light and heavy metals from common sources.

Unsuspected prolonged exposure to abnormal environmental (very high frequency) electro-magnetic fields (EMF), electric fields (EF) or magnetic fields (MF) at 60 Hz or 16K Hz in the bedroom or workplace may contribute to the development of various intractable medical problems. Most of the clinical symptoms appear when the individuals are exposed to EMF for many hours a day for at least several months to 1-year for relatively benign diseases or symptoms (such as intractable pain or medical problems), or several to over 10 years for more serious diseases (such as cancers of the digestive system or other organs), all of which seem to appear with the additional co-existence of micro-circulatory disturbances with Thromboxane B2 (TXB2), bacterial or viral infections and decrease or absence of acetylcholine, and lead, mercury, or aluminum deposits, with or without asbestos. These abnormal environmental EMF's or EF's can be detected by the Bi-Digital O-Ring Test, which has good correlation with standard laboratory measurement, especially with EF measurement, and the distribution of EMF often includes a linear band-like appearance on the abnormal part of the patient's body, as well as on the patient's corresponding area of the bed, or at the workplace. These EMF's can be eliminated either by a metal sheet, acting as a reflector, which redirects the harmful EMF or eliminates it completely by grounding the metal sheet at high frequency range, while extremely low frequency (ELF) magnetic fields at the near field are more difficult to eliminate. Several examples of medical problems that appear to be associated with repeated and prolonged exposure to abnormal environmental EMF, EF or MF are summarized in this article. EF or MF-induced abnormalities were artificially and reversibly created in humans by exposing the extremities or head to a 10Volt/Meter (V/M) EF at 60 Hz about 33 (evening) to 50 cm (daytime or after midnight) from a pair of rubber insulated wires connected to an AC source, but where no current is passed, so that no extra MF exists. After exposing normal parts of the extremities and head to a 10 V/M EF for 5 minutes, abnormal increase of TXB2 and disappearance or significant reduction of acetylcholine was observed for 5 minutes, and slightly longer abnormal time duration was observed in those who have aluminum, lead, or mercury deposits. This indicates that the upper limit of relatively safe EF should be around 10V/M at 60 Hz rather than 25V/M at ELF by Swedish Government recommendation, which is now widely accepted.(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗

C/EBP alpha and Ets protein family members regulate the human myeloid IgA Fc receptor (Fc alpha R, CD89) promoter.

Fc alpha R (CD89), the FcR for IgA, is expressed exclusively in myeloid cells, including monocytes/macrophages, neutrophils, and eosinophils, and is thought to mediate IgA-triggered cellular functions in immunity. Here we demonstrate that the Fc alpha R 5'-flanking region from -102 to -64 relative to the ATG translation initiation codon is essential for promoter activity and contains two functional binding motifs for C/EBP and Ets family members at -74 and -92, respectively. EMSAs and cotransfection experiments show that C/EBP alpha acts as a major activator of the Fc alpha R promoter at least in immature myeloid cells. In addition, we found two additional functional targets of C/EBP alpha at -139 and -127. On the other hand, the Fc alpha R Ets binding motif could bind Elf-1 and mediate the trans-activation by cotransfected Elf-1, but a major component of the complex forming on this site appears to be an unidentified Ets-like nuclear protein that is preferentially detected in cells of hemopoietic origin. Furthermore, separation of the C/EBP and Ets binding sites reduces Fc alpha R promoter activity, suggesting some functional interaction between these factors. As the in vivo role of Fc alpha R is still incompletely defined, these findings reveal the features controlling the Fc alpha R promoter in myeloid lineage and provide a foundation for clarifying regulatory mechanisms of Fc alpha R gene expression associated with its potential roles.

5' Untranslated Regions↗

Transcriptional regulation of CD1D1 by Ets family transcription factors.

CD1 molecules are MHC class I-like glycoproteins specialized in presenting lipid/glycolipid Ags to T cells. The distinct cell-type specific expression of CD1D1 plays an important role in the development and function of NKT cells, a unique subset of immunoregulatory T cells. However, the mechanisms regulating CD1D1 expression are largely unknown. In this study, we have characterized the upstream region of the CD1D1 gene and identified a minimal promoter region within 200 bp from the translational start site of CD1D1 that exhibits cell-type specific promoter activity. Analysis of this region revealed an Ets binding site critical for CD1D1 promoter activity. Gel shift assays and chromatin immunoprecipitation experiments showed that Elf-1 and PU.1 bind to the CD1D1 promoter. Furthermore, we found that gene disruption of Elf-1 resulted in decreased CD1D1 expression on B cells but not other cell types, whereas conditional activation of PU.1 negatively regulated CD1D1 expression in PU.1-deficient myeloid cells. These findings are the first to demonstrate that Ets proteins are involved in the transcriptional regulation of CD1D1 and that they may function uniquely in different cell types.

Animals↗

Measurements of extremely low-frequency magnetic fields around video display terminals.

The extremely low-frequency (ELF) magnetic field emissions of seven video display terminal (VDT) models were measured. A measuring coil with a linearized frequency response (50 Hz to 25 kHz) was used. The dominating ELF magnetic field around the terminals was the 50 or 60 Hz asymmetric triangular waveform from the vertical deflection coil of the cathode ray tube. At the distance of 50 cm, the magnetic field strength was still slightly higher than the background level in usual office rooms, but several orders of magnitude lower than the thresholds of known interaction mechanisms. Some recent experiments suggest that certain biological effects may occur at field strengths only a few times higher than those found at the position of VDT operators, but the significance of these effects to human health is not known.

Computer Systems↗

[Nasal soluble levels of ICAM-1 in allergic rhinitis].

UNLABELLED: Adhesion molecules, such as intercellular adhesion molecule-1 (ICAM-1), play an important role in the development of the inflammatory allergic response in the nose. ICAM-1 expression on nasal epithelial cells during allergic reaction is regarded as a major hallmark of allergic inflammation. OBJECTIVE: The aim of the study was to evaluate the levels of soluble ICAM-1 (sICAM-1) in nasal epithelial lining fluid (ELF) in patients with allergic rhinitis. PATIENTS: Seventeen patients with perennial allergic rhinitis (age: 34,6 +/- 14,6) were screened and the results were compared with those from 11 seasonal allergic rhinitis patients (age: 25.9 +/- 7.4) and 10 non-allergic patients. METHODS: The study was performed outside the pollen season. The scores of subjective symptoms were estimated by two differents methods. First, on the basis of a visual analog scale for the symptoms including nasal obstruction, rhinorrhea, sneezing and pruritus. This score was called "Autoscore" (fullmark =40 points). Second, on the basis of a four mark scale for each symptom defined (0 =no symptom, 1 =mild, 2 =moderate, 3 =severe). This score was called "Heteroscore" (fullmark =12 points). Specimens of nasal mucosa were collected by brushing the surface of nasal cavity. Levels of sICAM-1 and sECP (soluble Eosinophilic cationic protein) were measured by specific enzyme-linked immunosorbent assay. RESULTS: The levels of sICAM-1 in ELF were significantly higher (p <0.01) in patients with perennial rhinitis compared to patients with seasonal rhinitis outside the pollen season and to non allergic patients. Levels of sICAM-1 in patients with perennial allergic rhinitis were correlated with levels of sECP (p <0.003) and with the four mark scale scores (p <0. 03) but did not correlate with the visual analog scale scores. CONCLUSIONS: sICAM-1 increased in nasal secretions during natural perennial rhinitis and could be considered as a representative hallmark for clinical severity and follow-up evaluation in perennial allergic rhinitis.

Adult↗

[Effects of extremely low frequency weak magnetic fields on the intracellular free calcium concentration in PC-12 tumor cells].

In this study the effects of the extremely low frequency (ELF) magnetic fields on intracellular Ca2+ concentration ([Ca2+]i) of rat chromaffinoma PC-12 cells were examined by using a digital fluorescence image microscopy system. A 50 Hz, 100 microT sinusoidal ELF magnetic field increased [Ca2+]i to a marked level, whereas a static field or a field of higher frequency (2000 Hz) did not cause a [Ca2+]i increase. The magnetic field-induced [Ca2+]i rise was partly due to an influx of extracellular Ca2+ and partly due to the release of intracellular Ca2+ pool. It seemed likely that the Ca2+ transport ability of the cell membranes was increased by the 50 Hz magnetic field.

Animals↗

Influence of alternating low frequency magnetic fields on reactivity of central dopamine receptors in neonatal 6-hydroxydopamine treated rats.

The aim of this study was to evaluate the influence of extremely low frequency magnetic field (ELF MF) on the reactivity of the central dopamine D(1) receptor in rats with dopamine neurons chemically damaged by 6-hydroxydopamine (6-OHDA), an animal model of human's Parkinson's disease. The experiment was carried out on male Wistar rats. On day 3 of postnatal life, a lasting and selective chemical damage of the central dopamine system was induced in the rats by infusion of 6-OHDA HBr (133.4 microg intracerebroventricular, base form) given bilaterally into lateral ventricles of the brain. Control animals received similar treatments injecting only vehicle. At 2 months of age, both 6-OHDA treated and control rats were randomly divided into two groups. Rats from the first group were exposed to 10 Hz sinusoidal, 1.8-3.8 mT magnetic field one hour daily for 14 days. Rats of the second group were sham exposed, with the applicator solenoid turned off. On the day after the final exposure the evaluations were made of the rat's spontaneous irritability, oral activity, and catalepsy. The MF exposed rat with chemically induced dopamine neurons damage exhibited a reduction of irritability and oral activity when stimulated with SKF 38393 (the agonist of central dopamine D(1) receptor) and some increase of catalepsy after administration of SCH 23390(the antagonist of central dopamine D(1) receptor). These results indicate that ELF MF reduce the reactivity of central dopamine D(1) receptors in rats.

Animals↗

[Infantile leukemia and exposure to 50/60 Hz magnetic fields: review of epidemiologic evidence in 2000].

We review the epidemiological evidence on childhood leukemia and residential exposure to 50/60 Hz magnetic fields. The possibility of carcinogenic effects of power frequency magnetic fields (ELF-EMF), at levels below units of micro tesla (microT), was first raised in 1979 by a case-control study on childhood cancer carried out in Denver, USA. In that study, excess risks of total cancer and leukemia were observed among children living in homes with "high or very high current configuration", as categorised on the basis of proximity to electric lines and transformers. Many other epidemiological studies have been published since then, characterised by improved--although still not optimal--methods of exposure assessment. At the end of 2000, the epidemiological evidence to support the association between exposure to extremely-low-frequency magnetic fields and the risk of childhood leukemia is less consistent than what was observed in the mid 90s. At the same time, a growing body of experimental evidence has accumulated against both a direct and a promoting carcinogenic effect of ELF-EMF. Such "negative" experimental evidence hampers a causal interpretation of the "positive" epidemiological studies.

Child↗

Bronchoalveolar glutathione and nitrite/nitrate in idiopathic pulmonary fibrosis and sarcoidosis.

BACKGROUND AND AIM OF THE WORK: Bronchoalveolar lavage (BAL) is useful in diagnosis and management of interstitial lung diseases. Glutathione (GSH) represents an important defence molecule against reactive oxygen species produced during inflammation, which underlies both idiopathic pulmonary fibrosis (IPF) and sarcoidosis. Nitric oxide has been suggested as a marker of airway inflammation. The aim of this study was to examine the content of GSH and NO stable metabolites, nitrite/nitrate, in the BAL of a group of patients with IPF and sarcoidosis. METHODS: BAL was performed in 13 patients with newly diagnosed IPF, 13 patients with sarcoidosis and 4 controls. Total GSH and nitrite/nitrate were measured. BAL was repeated, in 5 patients with IPF, after 6 and 12 months and GSH was measured again. RESULTS: IPF patients had significantly lower levels of total GSH compared to sarcoidosis patients or controls (129 +/- 22 vs. 324 +/- 40 and 383 +/- 23 mM; p < 0.001) in the epithelial lining fluid (ELF). In patients with IPF (n = 5), total GSH levels in the ELF increased after 6 and 12 months (T0 = 98 +/- 19; T6 = 219 +/- 22; T12 = 301 +/- 34 microM; p < 0.05) following therapy with immunosuppressive drugs such as corticosteroids, methotrexate, cyclosporin A. Levels of nitrite/nitrate were found significantly elevated in IPF (n = 8) and sarcoidosis (n = 10) patients compared to controls (230 +/- 37 and 216 +/- 36 vs. 86 +/- 11 microM; p < 0.05). CONCLUSION: These observations support the role of inflammation and antioxidant defences in interstitial lung diseases and may provide insights into the pathogenesis of oxidant-induced interstitial disease and their therapy.

Bronchoalveolar Lavage Fluid↗

Electromagnetic exposure effects the hippocampal dentate cell proliferation in gerbils (Meriones unguiculatus).

The chronic effect on hippocampal neurogenesis after exposure (30 min/day for 14 days) to a high frequency (35,53 kHz) electromagnetic field, double modulated at extremely low frequencies (ELF; 1, 8, 12, 29 and 50 Hz), was studied in young adult gerbils. Immediately after the last exposure proliferation of dentate granule cells was identified by in vivo labeling with 5-bromo-2-desoxyuridine (BrdU). Exposure to 1, 29 and 50 Hz resulted in a statistically significant reduction of cell proliferation rates, but only the 50 Hz-group manifested the effect highly significantly (-29,3 %). On the other hand, gerbils exposed to 8 and 12 Hz showed no significant change of postmitotic cell proliferation as compared with the sham treated controls. The results suggest that the effects of ELF on the granule cell proliferation are mediated by neurotransmitters and hormones which regulate hippocampal neurogenesis.

Animals↗

[Clinical characterization of interleukin-8 in patients with idiopathic pulmonary fibrosis].

The levels of interleukin-8 (IL-8) in the serum, bronchoalveolar fluid (BALF) and epithelial lining fluid (ELF) were measured in patients with idiopathic pulmonary fibrosis. (IPF), in order to evaluate the clinical significance of IL-8. The serum levels were significantly higher in patients with active IPF (34.4 +/- 11.9 pg/ml, n = 8) than in those with stable IPF (mean: 14.6 +/- 10.9 pg/ml, n = 18), but neither correlated with the serum level of KL-6 or of SP-D, or with the intensity of chest Ga67-scintigraphy. There were no significant differences in BALF or ELF IL-8 levels between the active and stable IPF groups. These results suggest that the serum level of IL-8 is a useful marker for evaluating the disease activity in patients with IPF.

Aged↗

[Effects of extremely low frequency electromagnetic field and its combination with lead on the antioxidant system in mouse].

OBJECTIVE: To study the effects of extremely low frequency electromagnetic field(ELF EMF) and its combination with lead on the antioxidant system in mouse brain and liver tissues. METHOD: Mice were exposed to a 50 Hz sinusoidal 0.2 mT or 6.0 mT EMF for 2 weeks. At the same time, some groups were exposed to lead(50 mg/kg). After the exposure, the antioxidant system and cell membrane fluidity in brain and liver were measured. RESULTS: Malondiadehyde(MDA) content in brain and liver increased from the control levels of (1.33 +/- 0.12) and (3.95 +/- 0.21) nmol/mg pro to (1.35 +/- 0.09) and (6.15 +/- 0.28) nmol/mg pro respectively following 0.2 mT exposure, and to (3.98 +/- 0.10) and (6.50 +/- 0.79) nmol/mg pro respectively following 6.0 mT exposure. Total antioxidant capability(T-AOC) in brain and liver decreased from the control levels of (4.39 +/- 0.48) and (2.45 +/- 0.21) U/mg pro to (3.99 +/- 0.39) and (1.92 +/- 0.32) U/mg pro respectively following 0.2 mT, and to (3.12 +/- 0.37) and (1.57 +/- 0.14) U/mg pro respectively following 6.0 mT. GSH content decreased only in liver tissue from the control level of (194.60 +/- 20.93) mg/g pro to (189.24 +/- 5.61) mg/g pro(0.2 mT) and (153.04 +/- 1.18) mg/g pro(6.0 mT). Cellular membrane fluidity decreased from the control levels of (1.396 +/- 0.040) and (2.899 +/- 0.552) to (1.224 +/- 0.190) and (1.894 +/- 0.0761) (0.2 mT), (1.159 +/- 0.179) and (1.516 +/- 0.204)(6.0 mT) respectively. Compared with single EMF exposure(6.0 mT), EMF combined with lead exposure induced remarkable increase in MDA, GSH content and T-AOC and decrease in cell membrane fluidity both in the brain and liver, and increase in SOD activity only in liver. CONCLUSION: ELF EMF might alter the metabolism of free radicals, decrease anti-oxidant capability and enhance lipid peroxidation. The combination of EMF with lead showed synergic effects on lipid peroxidation.

Animals↗

[Effects of extremely low frequency electromagnetic fields on apoptosis and cell cycle of mouse brain and liver cells].

OBJECTIVE: To study the effects of extremely low frequency electromagnetic fields (ELF EMFs) on apoptosis and cell cycle of mouse brain and liver cells. METHODS: Mice were exposed to 50 Hz, 0.2 mT or 6.0 mT electromagnetic fields for 2 weeks. TUNEL and flow cytometric methods were used to analyze apoptosis and cell cycle of brain and liver cells. RESULTS: After exposure to 0.2 mT and 6.0 mT ELF EMFs for 2 weeks, apoptosis rates of brain cells [(5.60 +/- 1.47)% and (4.73 +/- 0.48)% respectively] were higher than that of control [(2.90 +/- 0.75)%], and apoptosis rates of liver cells [(4.19 +/- 2.08)% and (3.38 +/- 0.65)% respectively] were higher than that of control [(1.84 +/- 0.76)%]. G0/G1 cell percentage of brain cells [(80.21 +/- 1.68)% and (79.54 +/- 0.56)% respectively] were higher than that of control [(76.85 +/- 0.83)%], and those of liver cells [(79.42 +/- 1.80)% and (80.47 +/- 1.79)% respectively] were higher than that of control [(73.36 +/- 3.10)%]. The above differences were all statistically significant as P < 0.05. At the same time S and G2 + M cell percentage of brain and liver cells were significantly decreased. CONCLUSION: Exposure to 50 Hz EMFs may alter cell cycle and induce apoptosis of mouse brain and liver cells.

Animals↗

[Effects of extremely low frequency electromagnetic fields on male reproduction in mice].

OBJECTIVE: To investigate the effects of extremely low frequency electromagnetic fields (ELF EMFs) on male reproduction in mice. METHODS: 94 adult male mice were exposed to 50 Hz sinusoidal electromagnetic fields of 0.2, 3.2 or 6.4 mT for 2 weeks or 4 weeks. Testicular histology and weight, sperm amount, sperm motility and morphology were measured. The percentages of different ploidy cells and cell phases, and DNA content of testis cells were estimated by flow cytometry. The micronucleus rate of bone-marrow cell was also observed. RESULTS: The testicular weight of the mice exposed to 6.4 mT for 4 weeks [(76.06 +/- 32.25) mg] was significantly lower than that of the control [(111.44 +/- 19.99) mg, P < 0.05]; no significant histopathological changes were observed on the testis in EMFs exposed mice;the sperm amount was decreased after EMFs exposure for 4 weeks, and those of the mice exposed to 0.2 mT and 6.4 mT for 4 weeks [(4.87 +/- 0.94) x 10(6)/ml and (4.30 +/- 1.89) x 10(6)/ml respectively] were significantly lower than that of the control [(6.67 +/- 0.70) x 10(6)/ml, P < 0.05]; the rates of sperm motility also showed a decline. After 0.2, 3.2 or 6.4 mT EMFs exposure for 2 weeks, the deformity rates of sperm [(7.416 +/- 3.352)%, (6.862 +/- 2.947)% and (8.112 +/- 4.615)% respectively] were significantly higher than that of the control [(4.098 +/- 2.028)%, P < 0.01]. Similarly, those of the mice exposed for 4 weeks [(10.267 +/- 3.836)%, (11.027 +/- 7.059)%, (8.814 +/- 3.678)% respectively] were higher than that of the control [(3.714 +/- 1.830)%]. After 6.4 mT exposure for 2 weeks, the percentages of 1C testis cells [(69.56 +/- 4.07)%] was significantly lower than that of the control [(73.45 +/- 3.10)%, P < 0.05]. There were not any remarkable changes in those of 2C, 4C cells. DNA content in different ploidy cells of the mice exposed to 6.4 mT was decreased. Moreover, the cell percentage in S phase was increased significantly (P < 0.01). CONCLUSION: ELF EMFs exposure may have some adverse effects on reproduction in mice.

Animals↗

Effects of 60 Hz electromagnetic field exposure on testicular germ cell apoptosis in mice.

AIM: To evaluate the effects of 60 Hz extremely low frequency (ELF) elelctromagnetic field (EMF) exposure on germ cell apoptosis in the testis of mice. METHODS: Adult male BALB/c mice (7 weeks of age) were exposed to a 60 Hz EMF of 0.1 mT or 0.5 mT for 24 h/day. A sham-exposed group served as the control. After 8 weeks of exposure, the mice were sacrificed. Germ cell apoptosis in the testis was assessed by histopathological examination, the terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling assay (TUNEL) and flow cytometric examination of isolated spermatogenic cells stained with 7 aminoactinomycin D (7-AAD). RESULTS: EMF exposure did not significantly affect the body and testis weights, but significantly increased the incidence of germ cell death. The distinguishing morphological feature of EMF exposure was a decrement in the number of well organized seminiferous tubules. Quantitative analysis of TUNEL-positive germ cells showed a significantly higher apoptotic rate in the 0.5 mT exposed mice than that in the sham controls (P<0.05), while the difference between the two exposed groups was insignificant. The TUNEL-positive cells were mainly spermatogonia. In flow cytometry analysis, the percentage of live cells [forward scatter count (FSC)(high)7-AAD(-)] was lower in the exposed groups than that in the controls (Figure 5A), but the decrease in viability was not statistically significant. CONCLUSION: Continuous exposure to ELF EMF may induce testicular germ cell apoptosis in mice.

Animals↗

Exposure assessment for electric and magnetic fields.

Exposure assessment for extremely low frequency (ELF) electric and magnetic fields (EMF) is discussed. It is suggested that such assessments can be designed by attempting to mimic the receptor's experience of interest. Present efforts are, however, hampered by the lack of clearly defined human health effects, or even important interaction mechanisms, which might be used to define the appropriate exposure measure, the experience of interest. The state of the art of ELF EMF exposure assessment is described, including the use of surrogates, models, and available instrumentation. Data indicate that magnetic field levels in the home are of the order of 0.1 microT and that nonoccupational total exposures may best be predicted by levels in the bedroom. Occupational exposures may be orders of magnitude higher where high currents are present.

Carbon Monoxide↗