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Metabolizm tlenowy krwinek płytkowych eksponowanych na promieniowanie elektromagnetyczne generowane przez telefonie komórkowa - badania IN VITRO

Buczynski A., Dziedziczak-Buczyńska M., Jankowski W., Olszański R., Buczyński J., Pacholski K., Henrykowska G.

Polish Hyperbaric Research

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2007

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Nr 4(21)

31-37

PL

Celem pracy była ocena wpływu promieniowania elektromagnetycznego wysokiej częstotliwości emitowanego przez telefon komórkowy, na metabolizm tlenowy i zmiany wolnorodnikowe w krwinkach płytkowych. Zawiesinę ludzkich płytek krwi poddano działaniu pola EM o częstotliwości 900 i 1800 MHz przez 1, 3, 5 minut. W porównaniu do wartości kontrolnych aktywność dysmutazy ponadtlenkowej zmalała po 1,i 5 , a po 3 minucie wzrosła (EM 900 MHz). Promieniowanie o częstotliwości 1800 MHz powodowało stały spadek SOD-1 w stosunku do długości czasu ekspozycji. Stężenie dialdehydu malonowego wzrosło po 1 i 5 min ekspozycji, natomiast po 3 minutach odnotowano istotne jego obniżenie (EM 900 MHz). Promieniowanie o częstotliwości 1800 MHz powodowało wzrost stężenia MDA w stosunku do długości czasu ekspozycji. Na podstawie uzyskanych wyników można stwierdzić, że przyczyną niekorzystnych zmian w czynności enzymów antyoksydacyjnych i stężeniu dialdehydu malonowego może być stres oksydacyjny powstający przy narażeniu krwinek płytkowych na mikrofale, a wraz z nim tworzenie się nadmiernej ilości wolnych rodników tlenowych.

EN

The aim of the study was to assess the influence of electromagnetic field produced by mobile phones on oxygen metabolism In human blond plateletes. The suspension of blood platelets was exposed to the electromagnetic field with frequency of 900 and 1800 MHz after 1, 3, 5 min. Our studies demonstrated that microwaves produced by mobile phones (900 MHz) significantly depleted SOD-1 activity after 1, 5 min exposure and increased after 3 min in comparison with the control test. Microwaves 1800 MHz significantly depleted SOD-1 activity after 1, 3 and 5 min in comparison with the control test. There was a significant increase in concentration of MDA after 1, 5 min and decrease after 3 min of exposure as compared with the control test (900 MHz). Electromagnetic field tith frequency of 1800 MHz significantly increased in concentration of MDA after 1, 3, 5 min. On the grounds of our results we conclude that oxidative stress after exposure to microwaves may be the reason for many adverse changes in cells and may cause a number of systemic disturbance in the human body.

2

The energy approach for prediction of the behaviour of the notched specimens and components

Buczynski A., Glinka G., Baum Ch.

Zeszyty Naukowe. Mechanika / Politechnika Opolska

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2002

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z. 73

27-45

EN

The stress-strain behaviour in the notch tip of elastic-plastic bodies is discussed in the presentation. The approach is based on the incremental formulation which relates hypothetical elastic energy density to elastic-plastic energy density at the notch root. The Mróz-Garud multisurface cyclic plasticity theory is employed for simulation of the material response due to the current load increments. The equations of the energy density balance in the notch root together with constitutive relations formulate a set of algebraic equations. The fictitious elastic load history at the notch root and the material constitutive relations provide the parameters, so that the set of equations can be easily solved for the stress and strain increments. A shaft with a circumferential notch subjected to random load events is addressed to as an example of a component specified to predict the material stress-strain behaviour. The calculation results, obtained for general non-proportional load paths, are compared to the corresponding finite element data.

3

Computer visualization of the material stress-strain behaviour after Mróz model and typical effects

Buczynski A., Baum Ch.

Zeszyty Naukowe. Mechanika / Politechnika Opolska

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2002

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z. 73

11-25

EN

The discussion addresses the description of material behaviour due to stress-controlled load histories. It is restricted to 2D-problems, and a principal stress piane will be employed to demonstrate specified load events, assuming that the principal stress components are fixed to the material element. In order to tracę the general rules of the model evolution, due to the current load development, the assumptions postulated in the original formulation are described. As it was originally composed, the plastic module field and its variations, in respect to the actual load event of the considered load path, will be demonstrated. The attention will be paid to the ability to reproduce the Bausch-inger effect, and the plastic strain accumulation occurring under specific nonpropor-tional load conditions.