Martirosyan V.,Chair in Life science International Postgraduate Educational Center |
Markosyan L.,Armenian National Academy of Sciences |
Hovhanesyan H.,Armenian National Academy of Sciences |
Hovnanyan K.,Institute of Molecular Biology |
Ayrapetyan S.,Chair in Life science International Postgraduate Educational Center
Environmentalist | Year: 2012
The aim of this work was to investigate the frequency-dependent effects of extremely low-frequency electromagnetic field (ELF-EMF) and mechanical vibration at infrasound frequency (MV at IS frequency or MV) on growth and development of Escherichia coli K-12, by using classical microbiological (counting colony forming units), isotopic, spectrophotometric and electronmicroscopic methods. The frequency-dependent effects of MV and ELF-EMF were shown that they could either stimulate or inhibit the growth and the division of microbes depending on the periods following exposure. However, the mechanism through which the MV and ELF-EMF effects affect the bacteria cell is not clear yet. It was suggested that the aqua medium could serve a target through which the biological effect of MV and ELF-EMF on microbes could be realized. To check this hypothesis, the frequency-dependent effects (2, 4, 6, 8, 10 Hz) of both MV and ELF-EMF on the bacterial growth, division and their motility in cases of exposure, the preliminary treated microbes-free medium and microbes containing medium were studied. Both MV and ELF-EMF effect on microbes have frequency and post-exposure period duration-dependent characters. The [ 3H]-thymidine involving experiments shown that EMF at 4 Hz exposure has pronounced stimulation effect on cell proliferation while 4 Hz MV has inhibition effect. But at 8-10 Hz, the both EMF and MV have inhibitory effects on cell proliferation. It is suggested that 4 and 8 Hz EMF have different biological effects on microbes. © 2011 Springer Science+Business Media, LLC.
Ayrapetyan S.,Chair in Life science International Postgraduate Educational Center |
De J.,Chair in Life science International Postgraduate Educational Center
TheScientificWorldJournal | Year: 2014
"Changes in cell hydration" have been hypothesized as an input signal for intracellular metabolic cascade responsible for biological effects of nonionizing radiation (NIR). To test this hypothesis a comparative study on the impacts of different temperature and NIR (infrasound frequency mechanical vibration (MV), static magnetic field (SMF), extremely low frequency electromagnetic field (ELF EMF), and microwave (MW)) pretreated water on the hydration of barley seeds in its dormant and germination periods was performed. In dormant state temperature sensitivity (Q 10) of seed hydration in distilled water (DW) was less than 2, and it was nonsensitive to NIR treated DW, whereas during the germination period (48-72 hours) seeds hydration exhibited temperature sensitivity Q 10 > 2 and higher sensitivity to NIR treated DW. Obtained data allow us to suggest that the metabolic driving of intracellular water dynamics accompanied by hydrogen bonding and breaking is more sensitive to NIR-induced water structure changes in seed bathing aqua medium than the simple thermodynamic processes such as osmotic gradient driven water absorption by seeds in dormant state. Therefore, cell hydration is suggested to be a universal and extrasensitive biomarker for detection of biological effects of NIR on cells and organisms.
Heqimyan A.,Chair in Life science International Postgraduate Educational Center |
Narinyan L.,Chair in Life science International Postgraduate Educational Center |
Nikoghosyan A.,Chair in Life science International Postgraduate Educational Center |
Deghoyan A.,Chair in Life science International Postgraduate Educational Center |
And 2 more authors.
Environmentalist | Year: 2012
Age dependency of [ 3H]-ouabain binding, 45Ca 2+ eflux and its magnetosensitivity in rats' brain cortex and heart muscle tissues were studied. Curves of dose-dependent [ 3H]-ouabain binding consisted of three components with different affinities (10 -7-10 -4 M (α 1); 10 -9-10 -7 M (α 2); and 10 -11-10 -9 M (α 3)). These curves were also characterized by different dose-dependent kinetics. [ 3H]-ouabain binding with α 3 receptors in brain cortex and heart muscle tissues of young and adult animals had a dose-dependent character, while that in old ones had a dose-independent character. A 0.2 T static magnetic field (SMF) exposure had modulation effect on ouabain binding with α 1, α 2 and α 3 receptors in young rats, while in adult ones, only α 3 receptors were magnetosensitive. In old animals, SMF exposure had no significant effect on ouabain binding with α 3 receptors in brain cortex, while in heart muscle, it had inhibitory effect on it. Age-dependent effect of ouabain impact on 45Ca 2+ efflux showed that all concentrations of ouabain lead to inhibitory effect in young animals' brain cortex and heart muscle (with the exception of 10 -10 and 10 -6 M), while in old ones, it had activation effect as compared with data received without ouabain. SMF exposure in young animals had activation effect on 45Ca 2+ efflux from brain cortex and heart muscle in data without ouabain, and in old rats, 45Ca 2+ efflux from brain cortex was magnetic insensitive. In old animals, SMF increased 45Ca 2+ efflux even after extra low concentration of ouabain. It is suggested that α 3 receptors having a crucial role in the regulation of Na +/Ca 2+ exchange serve as age-dependent magnetosensors of excitable cells. © 2012 Springer Science+Business Media, LLC.