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PubMed1991

Inhibition of hypochlorous acid by lidocaine and native components of alveolar epithelial lining fluid.

Alveolar epithelial lining fluid (ELF) contains several antioxidant substances that may provide in vivo protection. We studied the ability of ELF and ELF components to inhibit the neutrophil oxidant hypochlorous acid (HOCI). Normal bronchoalveolar lavage fluid containing ELF was incubated with physiologically relevant concentrations of HOCI (0.04 mM). After incubation, residual HOCI activity was titered by the iodide method. The inhibitory activity of lavage fluid was unexpectedly strong. For example, lavage fluid diluted 20-fold in the assay system quenched 49% of starting HOCI. We initially postulated that ELF total protein and glutathione would account for most of the inhibition of HOCI. However, several experimental approaches demonstrated that the total protein and glutathione concentrations in diluted lavage fluid were too low to explain the observed inhibition. Instead, the majority of HOCI inhibition was due to the lidocaine used for upper airway anesthesia. Reagent lidocaine exhibited strong reactivity in the HOCI assay system. Furthermore, the lavage fluid lidocaine concentration (32.4 +/- 6.9 micrograms/ml) was sufficient to explain most of the observed quenching activity. Additional experiments explored the hypothetical quenching activity of ELF components devoid of lidocaine. These findings demonstrate the technical problems posed by lidocaine in antioxidant studies involving lavage fluid or ELF.

Adult↗

PubMed1999

A high-resolution, fluorescence-based method for localization of endogenous alkaline phosphatase activity.

We describe a high-resolution, fluorescence-based method for localizing endogenous alkaline phosphatase in tissues and cultured cells. This method utilizes ELF (Enzyme-Labeled Fluorescence)-97 phosphate, which yields an intensely fluorescent yellow-green precipitate at the site of enzymatic activity. We compared zebrafish intestine, ovary, and kidney cryosections stained for endogenous alkaline phosphatase using four histochemical techniques: ELF-97 phosphate, Gomori method, BCIP/NBT, and naphthol AS-MX phosphate coupled with Fast Blue BB (colored) and Fast Red TR (fluorescent) diazonium salts. Each method localized endogenous alkaline phosphatase to the same specific sample regions. However, we found that sections labeled using ELF-97 phosphate exhibited significantly better resolution than the other samples. The enzymatic product remained highly localized to the site of enzymatic activity, whereas signals generated using the other methods diffused. We found that the ELF-97 precipitate was more photostable than the Fast Red TR azo dye adduct. Using ELF-97 phosphate in cultured cells, we detected an intracellular activity that was only weakly labeled with the other methods, but co-localized with an antibody against alkaline phosphatase, suggesting that the ELF-97 phosphate provided greater sensitivity. Finally, we found that detecting endogenous alkaline phosphatase with ELF-97 phosphate was compatible with the use of antibodies and lectins. (J Histochem Cytochem 47:1443-1455, 1999)

Alkaline Phosphatase↗

PubMed1995

Use of a new fluorogenic phosphatase substrate in immunohistochemical applications.

We used the phosphatase substrate 2-(5'-chloro-2'-phosphoryloxyphenyl)-6- chloro-4-[3H]-quinazolinone, with standard alkaline phosphatase-mediated immunohistochemical techniques, to visualize a number of antibodies that bind to adult zebrafish retinal tissue. This compound, known as the ELF (enzyme-labeled-fluorescence) phosphatase substrate, produces a precipitate that fluoresces at approximately 500-580 nm (bright yellow-green). We show that the precipitated product from the ELF phosphatase substrate has a number of characteristics that make it superior to fluorescein-labeled secondary reagents. The staining produced with the ELF substrate is much more photostable than that produced by fluorescein-labeled secondary reagents, thus allowing time to examine, focus, and photograph the ELF-labeled tissue under high magnification. Moreover, the ELF precipitate exhibits a Stokes shift of greater than 100 nm, a characteristic that has enabled us to overcome the problem of distinguishing signal from background in this autofluorescent tissue. In addition, we show that the ELF product's large Stokes shift makes the ELF substrate ideal for multicolor applications.

Alkaline Phosphatase↗

PubMed2004

Effect of sex and AIDS status on the plasma and intrapulmonary pharmacokinetics of rifampicin.

OBJECTIVE: To compare the steady-state plasma and intrapulmonary concentrations of oral rifampicin (rifampin) in men and women with and without AIDS. DESIGN: Prospective nonblinded pharmacokinetic study. PARTICIPANTS: Ten men with AIDS, ten men without AIDS, ten women with AIDS, and ten women without AIDS. METHODS: Rifampicin 600 mg was administered orally once daily for 5 days to 40 adult volunteers. Blood was obtained 2 hours after the last dose and at the time of bronchoalveolar lavage (BAL) performed 4 hours after the last dose. Rifampicin was measured in plasma, epithelial lining fluid (ELF) and alveolar cells. Standardised BAL was performed without systemic sedation. The volume of ELF was calculated by the urea dilution method, and alveolar cells were recovered by a standardised centrifugation technique. The volume of alveolar cells was calculated from the cell count and differential performed on the BAL fluid. Rifampicin was measured by high-performance liquid chromatography. RESULTS: Sex or AIDS status had no effect on plasma concentrations of rifampicin at 2 hours, 4 hours, or in ELF. Plasma concentrations (mean +/- SD) of rifampicin at 2 hours (9.15 +/- 5.4 mg/L) were not significantly different (p > 0.05) from those at 4 hours (9.10 +/- 5.6 mg/L) following the last dose. The ELF concentration was 2.0 +/- 1.6 mg/L with a range of 0-7.3 mg/L and the ELF/plasma ratio at 4 hours was 0.2 +/- 0.2. Rifampicin was not detectable in ELF in eight subjects (three with AIDS and five without AIDS) or in alveolar cells in three subjects without AIDS. There was no significant effect of AIDS on alveolar cell concentrations of rifampicin. Alveolar cell concentrations of rifampicin were significantly greater in women (13.9 +/- 6.7 mg/L) than in men (6.6 +/- 4.1 mg/L) [p = 0.0003]. Alveolar cell rifampicin concentrations were 78% greater in smoking women (17.8 +/- 7.0 mg/L) than in nonsmoking women (10.0 +/- 2.4 mg/L), but the difference was not significant (p > 0.05). CD4+ cell counts in the AIDS subjects were not correlated with the concentrations of rifampicin in plasma, ELF or alveolar cells. CONCLUSIONS: The absorption of oral rifampicin was not affected by sex or AIDS. Plasma and alveolar cell concentrations were not significantly different, were both greater than ELF concentrations, and were adequate to inhibit Mycobacterium tuberculosis. Considerable interpatient variability was detected despite witnessed drug administration. The clinical significance of these findings is unknown but merits further investigation.

Acquired Immunodeficiency Syndrome↗

PubMed1996

Overexpression of the proto-oncogene/translation factor 4E in breast-carcinoma cell lines.

The expression of the proto-oncogene, translation factor elF-4E, was examined in breast-cell lines: 5 carcinomas and 2 normal. At the protein level, elF-4E was 10 times higher in the carcinoma lines than in normal cells, which is comparable to the level found in breast-cancer biopsies. The elevation appears to be due to increased transcription, since the elF-4E mRNA was correspondingly increased. These results demonstrate that cells isolated from naturally occurring breast carcinomas maintain an elevated expression of the factor. Turnover rates for elF-4E (mRNA and protein) were determined for normal and cancer cells. We found that elF-4e mRNA is relatively stable during an 8-hr incubation with Actinomycin D, but the half-life of the protein is fairly short (approximately 4.5 hr). This suggests that, in proliferating cells, elF-4E may be turning over rapidly, possibly to fine-tune the changes in translation rates which occur during the cell cycle.

Base Sequence↗

PubMed1997

Dramatic attenuation of hypusine formation on eukaryotic initiation factor 5A during senescence of IMR-90 human diploid fibroblasts.

Deoxyhypusine synthase catalyzes the conversion of lysine to deoxyhypusine residue on the eukaryotic initiation factor 5A (elF-5A) precursor using spermidine as the substrate. Subsequent hydroxylation of the deoxyhypusine residue completes hypusine formation on elF-5A. Hypusine formation is one of the most specific polyamine-dependent biochemical events in eukaryotic cells. Although changes in polyamine metabolism have been demonstrated in human diploid fibroblasts during senescence (Chen and Chang, 1986, J. Cell. Physiol., 128:27-32.), it is unclear whether or not polyamine-dependent hypusine formation itself is an age-dependent biochemical event. In the present study, hypusine-forming activity was measured by a radiolabeling assay in cells whose polyamines have been depleted by prior treatment of alpha-difluoromethyl ornithine (DFMO). In addition, an in vitro cross-labeling assay was developed for simultaneous measurement of the deoxyhypusine synthase activity and protein substrate (elF-5A precursor) amount. We showed that the hypusine-forming activity in low-passage presenescent IMR-90 cells [population doubling level (PDL) = 15-23, termed young cells] was prominently induced by serum whereas little or no hypusine-forming activity could be detected in late-passage senescent cells (PDL = 46-54, termed old cells). The striking difference in hypusine-forming activity between young and old cells was due to changes in both deoxyhypusine synthase activity and elF-5A precursor amount in IMR-90 cells during senescence. However, Northern blot analysis showed no significant difference in the elF-5A messenger RNA (mRNA) between young and old cells, suggesting that the age-dependent attenuation of elF-5A precursor protein may be regulated at either translational or post-translational level.

Antineoplastic Agents↗

PubMed2003

Extremely low frequency magnetic field exposure modulates the diurnal rhythm of the pain threshold in mice.

The aim of this study was to determine whether exposure to extremely low frequency magnetic field (ELF-MF) affects the normal diurnal rhythm of the pain threshold in mice. Pain thresholds were evaluated in mice using the hot plate test. A significant increase of pain threshold during night was observed compared to that during day. This rhythm was attenuated by both constant exposure to light (LL) and constant exposure to darkness (DD) for 5 days. Under DD exposure, the diurnal rhythm in pain threshold was restored when mice were exposed to ELF-MF (60 Hz, 1.5 mT for 12 h daily, from 08:00 to 20:00 h) for 5 days. The diurnal rhythm was not reversed under dark with reversed ELF-MF cycle (exposure to 1.5 mT from 20:00 to 08:00 h, next day) for 5 days, although pain threshold in the ELF-MF exposed period of night was slightly decreased. The diurnal rhythm of melatonin analgesic effect related to pain threshold was also observed under DD by the exposure of ELF-MF for 5 days, but not for 5 nights. The present results suggest that ELF-MF may participate in the diurnal rhythm of pain threshold by acting on the system that is associated with environmental light-dark cycle.

Animals↗

PubMed2005

A joint study based on the electron localization function and catastrophe theory of the chameleonic and centauric models for the Cope rearrangement of 1,5-hexadiene and its cyano derivatives.

A novel interpretation of the chameleonic and centauric models for the Cope rearrangements of 1,5-hexadiene (A) and different cyano derivatives (B: 2,5-dicyano, C: 1,3,4,6-tetracyano, and D: 1,3,5-tricyano) is presented by using the topological analysis of the electron localization function (ELF) and Thom's catastrophe theory (CT) on the reaction paths calculated at the B3LYP/6-31G(d,p) level. The progress of the reaction is monitorized by the changes of the ELF structural stability domains (SSD), each being change controlled by a turning point derived from CT. The reaction mechanism of the parent reaction A is characterized by nine ELF SSDs. All processes occur in the vicinity of the transition structure and corresponding to a concerted formation/breaking of C(1)-C(6) and C(3)-C(4) bonds, respectively, together with an accumulation of charge density onto C(2) and C(5) atoms. Reaction B presents the same number of ELF SSDs as A, but a different order appears; the presence of 2,5-dicyano substituents favors the formation of C(1)-C(6) bonds over the breaking of C(3)-C(4) bond process, changing the reaction mechanism from a concerted towards a stepwise, via a cyclohexane biradical intermediate. On the other side, reaction C presents the same type of turning points but two ELF SSD less than A or B; there is an enhancement of the C(3)-C(4) bond breaking process at an earlier stage of the reaction by delocalizing the electrons from the C(3)-C(4) bond among the cyano groups. In the case of competitive effects of cyano subsituents on each moiety, as it is for reaction D, seven different ELF SSDs have been identified separated by eight turning points (two of them occur simultaneously). Both processes, formation/breaking of C(1)-C(6) and C(3)-C(4) bonds, are slightly favored with respect to the parent reaction (A), and the TS presents mixed electronic features of both B and C. The employed methodology provides theoretical support for the centauric nature (half-allyl, half-radical) for the TS of D.

Journal Article↗

PubMed2004

No effects of intermittent 50 Hz EMF on cytoplasmic free calcium and on the mitochondrial membrane potential in human diploid fibroblasts.

The recently described increase in DNA strand breaks of cultured human diploid fibroblasts after intermittent exposure to extremely-low-frequency electromagnetic fields (ELF-EMF) of more than about 70 microT ELF-EMF is difficult to explain by a direct induction of covalent bond disruption. Therefore the hypothesis has been tested that ELF-EMF-induced DNA strand breaks might be mediated by cellular processes that cause alteration of the intracellular concentration of free calcium ([Ca2+]i) and/or the membrane potential (DeltaPsi(m)). [Ca2+]i was determined by the ratiometric fura-2 technique. Changes in DeltaPsi(m) were assessed by using the potential-dependent lipophilic cationic probe JC-1. Human fibroblasts were exposed to intermittent ELF-EMF (50 Hz, 1000 microT). Although exposure of fiboblasts to ELF-EMF resulted in a highly significant increase in DNA strand breaks as determined by the comet assay, no effect on JC-1 fluorescence emission or on [Ca2+]i has been observed when comparing exposed with sham-exposed cells. Therefore, it is suggested that ELF-EMF-induced DNA strand breaks are unlikely to be caused by intracellular changes that affect [Ca2+]i and/or DeltaPsi(m).

Calcium↗

PubMed2006

Effects of 17 b-estradiol and extremely low-frequency electromagnetic fields on social recognition memory in female rats: a possible interaction?

We have investigated a potential memory-enhancing effect of exposure to extremely low-frequency electromagnetic fields (ELF EMF) in female rats and its dependence on estrogen, using a social recognition task. A juvenile social recognition paradigm was used and memory retention tested at 30 and 300 min after an adult was exposed to a juvenile during two 4-min trials. Results showed that an intact social recognition memory was present at 30 min in both gonadally intact and ovariectomized rats with, or without, ELF-EMF. However, whereas gonadally intact control females failed to show retention of the recognition memory at 300 min, those additionally exposed to ELF EMF did. This shows that the enhanced duration effect of ELF EMF on social recognition memory occurs in gonadally intact females as well as in males. In addition, results showed that the ELF EMF facilitation of memory retention was prevented by ovariectomy but restored by exogenous treatment with estrogen. This suggests that this ELF EMF effect on social recognition memory is estrogen-dependent.

Age Factors↗

PubMed2006

Distribution characteristics of orally administered olamufloxacin, a newly synthesized fluoroquinolone antibacterial, in lung epithelial lining fluid and alveolar macrophage in rats.

This study described distribution characteristics of olamufloxacin (HSR-903) in lung epithelial lining fluid (ELF) and alveolar macrophage (AM) in rats, two important representative infectious sites in lower respiratory tract infections. The rats were orally administered at a dose of 10mg/kg. At each designated time, rats were sacrificed, and blood samples were collected from the superior vena cava, and ELF and AM samples were gathered by the bronchoalveolar lavage method. The AUC ratios of ELF/plasma and AM/plasma of HSR-903 were 3.03+/-0.54 and 97.5+/-24.2, respectively, notably higher than those of ciprofloxacin (CPFX). Kinetic analyses of concentration-time profiles of HSR-903 in ELF and AM indicated that the influx clearance from plasma to ELF across the alveolar barrier was 5.8-fold higher than the efflux clearance from ELF. Furthermore, the permeability of HSR-903 across the cultured AM plasma membrane was 5.5 and 14.5 times greater than those of CPFX and pipemidic acid (PPA), respectively. A significant correlation (r2 = 0.995) was achieved between permeability across AM plasma membrane and hydrophobicity, implying that passage through AM membrane was principally involved in the passive diffusion. The extent of AM intracellular binding was the greatest for grepafloxacin, followed by HSR-903, CPFX, levofloxacin and PPA. In conclusion, HSR-903 distributed more efficiently in ELF and AM than CPFX, and the high accumulation of HSR-903 by AM cells may be accounted for by both the high transferability across the AM membrane and avid binding to the membrane phospholipids.

Administration, Oral↗

PubMed2006

Effects of 50 Hz extremely low frequency magnetic field on the morphology and function of boar spermatozoa capacitated in vitro.

The aim of this study was to evaluate the effect of an acute exposure to a sinusoidal MF-ELF (50 Hz, 1mT) on the ability of boar mature spermatozoa to acquire the fertilizing competence in vitro. The spermatozoa exposed during the 4h of incubation to the MF-ELF were evaluated for morphological (surface morphology and acrosome integrity) and functional parameters (cell viability, motility, induction of acrosomal reaction, AR, and the ability to in vitro fertilize oocytes). In parallel, the intracellular Ca(2+) levels as well as the major mechanisms of Ca(2+) clearance were assessed: (45)Ca intakes and intracellular Ca(2+) sequestration by analyzing intracellular Ca(2+) elevation induced by thapsigargin or studying mitochondrial function with Mito-Tracker. The MF-ELF exposure did not affect sperm viability and morphology during the first h of incubation when sperm Ca(2+) homeostasis were already compromised. First of all, MF-ELF treated spermatozoa showed resting intracellular Ca(2+) levels significantly lower than those recorded in controls. This result was dependent on a lower extracellular Ca(2+) intake and from the inhibitory role exerted on both intracellular Ca(2+) storages. As a consequence, after 1h of incubation MF-ELF exposed cells displayed a reduced motility, a modest reactivity when coincubated with solubilized zonae pellucidae and a reduction in oocyte penetrating ability. After 2 or 4h of incubation, in addition, signs of morphological damage appeared on plasma membrane and at acrosomal level. In conclusion, MF-ELF influence negatively spermatozoa first by impairing cell Ca(2+) homeostasis then by dramatically affecting sperm morphology and function.

Animals↗

PubMed1999

Effect of electromagnetic fields on several CD markers and transcription and expression of CD4.

We carried out flow cytometric analysis for multiparametric evaluation of cell surface markers related to cellular functions. Specifically, we studied the expression of CD4, CD8, CD3, CD16, CD19, HLA-DR, and CD14 macrophage receptors expression and cell cycle progression on cells exposed to ELF-EMF. In addition, we tested the effects of ELF-EMF on CD4 mRNA protein transcription and translation and the cell-cycle progression using an immunofluorescence method. Our data show that same CD surface marker expression are weakly influenced by electromagnetic fields, with no differences between cells exposed or not exposed to ELF-EMFs. However, when the CD4 protein generation was studied, an indication of protein production was found in lymphocytes exposed to ELF-EMF, as evidenced by immunofluorescence, Western blotting and RT-PCR analysis. CD16 and CD14 expression were affected by EMF exposure at all times studied (24, 48, 72 h). The results obtained with cell cycle analysis show that after 48 h of exposure to ELF-EMF, PHA-activated and not activated cells in S phase increase with respect to non-exposed cells. The findings from this study demonstrate that under our defined experimental conditions there is evidence that ELF-EMF has a slight effect on CD4, CD14 and CD16 receptor expression, while the other CD receptors are not affected.

Antigens, CD↗

PubMedDate not supplied

Healing of chronic arterial and venous leg ulcers through systemic effects of electromagnetic fields [corrected].

BACKGROUND: Mitogen-activated autologous peripheral blood mononuclear cells applied locally on the ulcer surface promote healing of chronic arterial and venous leg ulcers. In vitro, extremely low frequency electromagnetic fields (ELF) interact with peripheral blood mononuclear cells (PBMC) via Ca++ channels, activating signal transduction cascades, promoting cytokine synthesis, and changing cell proliferation patterns. METHODS: ELF frequencies were configured to interact in vitro with the proliferation patterns of PBMC obtained from normal human volunteers. These ELF were then applied peripherally as the sole treatment to 26 patients with 42 chronic leg ulcers of predominantly arterial or venous etiology unresponsive to previous medical and/or surgical treatments in a phase I before-after design. RESULTS: At admission, age of ulcers had a skewed distribution with a median of 639 days. Wound healing or deleterious effects began in all patients during the first 2 weeks after ELF exposure, permitting their previously unresponsive ulcers to function as internal controls. After ELF exposure, 69% of all lesions were cured or healed >50% in a period <4 months. Defective wound healing was observed in lesions associated with important arterial occlusion, uncontrolled arterial hypertension, severe lipodermatosclerosis, non-pitting edema, and obesity (body mass index >30). Lesions worsened in patients with autoimmune diseases. CONCLUSIONS: Systemic effects are hypothetically explained by ELF activation of PBMC and their subsequent transportation to the ulcer site via humoral route. This therapy is effective in selected patients with chronic arterial and venous leg ulcers.

Arteries↗

PubMed2003

Mouse early embryos obtained by natural breeding or in vitro fertilization display a differential sensitivity to extremely low-frequency electromagnetic fields.

We have investigated the sensitivity of pre-implantation embryos obtained by natural breeding (NB) or in vitro fertilization (IVF) to extremely low-frequency magnetic fields (ELF-MF). Fertilized eggs obtained by NB were removed from mothers 12h after mating and cultured in vitro for 5 days under continuous ELF-MF exposure (constant strength of 50Hz and various intensities, i.e. 60, 120 and 220 microT). Alternatively, zygotes obtained by IVF were subjected to ELF-MF exposure (50Hz, 60 microT), starting 12h after IVF for 5 days. We found that ELF-MF exposure causes a small yet significant (P<0.05) decrease in the survival rate of NB-derived embryos at the latest stages of pre-implantation development, i.e. the eight cell-to-blastocyst transition. In embryos exposed to the highest field intensity (220 microT), the effect became apparent somewhat earlier. When IVF-derived embryos were exposed to ELF-MF, the reduction in the rate of embryo survival was more pronounced and the difference from controls was more significant (P<0.01). Moreover, the decreased survival rate in IVF embryos became apparent as early as the first cleavage and persisted throughout pre-implantation. These results suggest that IVF-derived embryos are more sensitive than NB-generated embryos to ELF-MF, and that this sensitivity occurs earlier in development.

Animals↗

PubMed2004

Four-dimensional elastic light-scattering fingerprints as preneoplastic markers in the rat model of colon carcinogenesis.

BACKGROUND & AIMS: Identification of preneoplastic changes in histologically normal epithelium (the "field effect") could provide a powerful screening tool for colorectal cancer. However, to date, reliable detection has not been possible. We have recently developed a new generation of optical technology, 4-dimensional elastic light-scattering fingerprinting (4D-ELF), which enables us to probe the nanoscale/microscale architecture of living cells. We therefore investigated whether 4D-ELF would be able to identify preneoplastic changes in the colonocytes of the azoxymethane (AOM)-treated rat model of colon carcinogenesis. METHODS: Forty-eight Fisher 344 rats were randomized to either 2 weekly injections of AOM or saline. Animals were killed 2-20 weeks after the second injection of AOM. Colons were removed and subjected to 4D-ELF analysis, with a subset undergoing assessment of aberrant crypt foci (ACF). All AOM-treated animals were compared with age-matched saline-treated controls. RESULTS: AOM-induced ACF became apparent at approximately 4-6 weeks and continued to increase over time. ACF were predominantly located in the distal colon. At 2 weeks (before development of ACF), there were marked changes in a number of 4D-ELF signatures. The relevance to carcinogenesis of these 4D-ELF-detected microarchitectural abnormalities is supported by their spatial and temporal correlation with subsequent development of ACF. All changes reported were highly statistically significant. CONCLUSIONS: We show that probing the nanoscale cellular architecture with 4D-ELF provided an unprecedented tool for detecting the earliest stages of colon carcinogenesis. Future studies are necessary to explore the clinical applicability of this technology and elucidate the biological determinants of these microarchitectural changes.

Animals↗

PubMed2005

Using urea dilution to standardise components of pleural and bronchoalveolar lavage fluids in the dog.

AIM: To develop a technique to estimate the volume of epithelial lining fluid (ELF) obtained during bronchoalveolar lavage (BAL) and pleural lavage (PL) in the dog, using the urea dilution method. METHODS: BAL and PL fluids were obtained by saline lavage of pulmonary and pleural cavities of nine clinically healthy mixed-breed dogs immediately after euthanasia. Cell counts in the BAL and PL fluids were measured using standard techniques. The concentration of ELF in each lavage fluid was calculated from the relative concentration of urea in plasma and in each type of lavage fluid. Cell counts in ELF were then calculated. RESULTS: There were substantially higher cell counts in ELF compared to BAL or PF fluid. However, nucleated cell counts in ELF could not be predicted from cell counts in BAL or PL fluid. CONCLUSIONS AND CLINICAL RELEVANCE: These results suggest that accurate assessment of cellular or non-cellular components in lavage fluids should include a calculation of the proportion of ELF recovered, using a method such as urea dilution.

Animals↗

PubMed2003

Occupational exposure to extremely low frequency magnetic fields and mortality from cardiovascular disease.

The authors evaluated the relation between occupational exposure to extremely low frequency (ELF) magnetic fields and mortality from cardiovascular diseases. The study was based on 27,790 subjects from the Swedish Twin Registry. Exposure to ELF magnetic fields was assessed by linking occupation reported in 1967 or 1973 to a job exposure matrix. Four levels of exposure were related to cause-specific mortality through 1996, and primary and contributing causes of death were considered. The authors estimated relative risks by Cox regression, with adjustment for several cardiovascular disease risk indicators. The authors calculated the synergy index to evaluate potential interaction between exposure to ELF magnetic fields (>0.2 microT) and genetic susceptibility to acute myocardial infarction (AMI). Arrhythmia-related death, ischemic heart disease other than AMI, and atherosclerosis showed no association with ELF magnetic fields. The authors found a low-level increase in AMI risk in the highest exposure group (relative risk=1.3, 95% confidence interval: 0.9, 1.9) and suggestions of an exposure-response relation (p=0.02). A synergy index of 2.7 (95% confidence interval: 1.1, 6.6) in monozygotic twins indicated that the risk of AMI was strengthened among ELF magnetic field-exposed subjects with genetic susceptibility to the disease. The results for AMI corroborate previous findings from the United States. The unusual opportunity to include genetic susceptibility in the present analyses showed that evaluations of effect modification in vulnerable subjects are warranted in ELF magnetic field research.

Adult↗