ISSN:
0197-8462
Schlagwort(e):
electromagnetic field
;
genome
;
viscosity
;
intercellular communication
;
extremely low frequency (ELF)
;
anomalous viscosity time dependence (AVTD)
;
genome conformational state (GCS)
;
Life and Medical Sciences
;
Occupational Health and Environmental Toxicology
Quelle:
Wiley InterScience Backfile Collection 1832-2000
Thema:
Biologie
,
Physik
Notizen:
The effects of weak magnetic fields of extremely low frequency (ELF) on E. coli K12 AB1157 cells were studied by the method of anomalous viscosity time dependencies (AVTD). E. coli cells at different densities within a range of 5 × 105-109 cell/ml were exposed to ELF (sinusoidal, 30 μT peak, 15 min) at a frequency of 9 Hz. A transient effect with maximum 40-120 min after exposure was observed. Kinetics of the per-cell-normalised ELF effects fitted well to a Gaussian distribution for all densities during exposure. A maximum value of these kinetics and a time for this maximum were strongly dependent on the cell density during exposure. These data suggest a cell-to-cell interaction during response to ELF. Both dependencies had three regions close to a plateau within the ranges of 3 × 105 - 2 × 107 cell/ml, 4 × 107 - 2 × 108 cell/ml and 4 × 108-109 cell/ml and two rather sharp transitions between these plateaus. The effect reached a maximum value at a density of 4 × 108 cell/ml. Practically no effect was observed at the lowest density of 3 × 105 cell/ml. The data suggested that the ELF effect was mainly caused by a secondary rather than a primary reaction. The filtrates from exposed cells neither induced significant AVTD changes in unexposed cells nor increased the ELF effect when were added to cells before exposure. The data did not provide evidence for significant contribution of stable chemical messengers, but some unstable compounds such as radicals could be involved in the mechanism of cell-to-cell interaction during response to ELF. The results obtained were also in accordance with a model based on an re-emission of secondary photons during resonance fluorescence. Bioelectromagnetics 19:300-309, 1998. © 1998 Wiley-Liss, Inc.
Zusätzliches Material:
4 Ill.
Materialart:
Digitale Medien
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