Effects of extremely low frequency electromagnetic fields on in-vitro cellular cultures HeLa and CHO.

This paper presents the cellular proliferation effects of the exposure to extremely low frequency electromagnetic fields (ELF-EMF) on in-vitro cellular cultures HeLa and CHO. Through the magnetic stimulation system (MSS) the cells were exposed to magnetic fields with sinusoidal waveform at 50 Hz; initially for 40 minutes at intensities of 0.4 mT, 1.4 mT, 2.13 mT, 2.49 mT and 2.53 mT in parallel and perpendicular directions to the culture plates. Subsequently, the repetitive electromagnetic field (rEMF) was applied to 2.49 mT in parallel direction (for 40 minutes every twelve hours during 4 days) with which the highest cellular proliferation rate was obtained at 66.6 %. The results show a greater effect on proliferation in radiated cell lines, particularly in the application of rEMF a greater effect of ELF-EMF was observed in the proliferation rate of HeLa cells than in CHO cells, in contrast to the respective control cells. These results supported by other studies serve as a reference in the search for alternatives for the treatment of cervical cancer and the maintenance and preservation of cell lines.

Effects of the ionophore anticoccidial semduramicin on broiler breeders.

Three experiments were conducted to assess the effects on broiler breeders of contamination of feed with the ionophore anticoccidial semduramicin. In Experiment 1, individually caged females received 0, 12.5, or 25 mg/kg diet for 3 wk from 48 to 50 wk of age. In Experiment 2, males and females in floor pens received 0, 12.5, or 25 mg/kg diet for 3 wk from 63 to 65 wk of age. In Experiment 3, individually caged males and females received 0, 3, 6, or 25 mg/kg diet for 1 wk at 31 wk of age and were mated by artificial insemination. There was a dose-related decrease in cumulative egg production and percentage shell in Experiment 1 after more than 1 wk exposure, but these effects were not observed in the other experiments. There was a decrease in cumulative fertile hatchability and a dose-related decrease after 3 wk exposure due to an increase in early embryonic mortality in Experiment 2, but these changes were not observed during the 1-wk exposure in Experiment 3. The data show that adverse effects of semduramicin require greater than 1 wk of exposure to be evident.