Essential oils (EOs) are lipophilic secondary metabolites obtained from plants; terpenoids represent the main components of them. A lot of studies showed neurotoxic actions of EOs. In insects, they cause paralysis followed by death. This feature let us consider components of EOs as potential bioinsecticides. The inhibition of acetylcholinesterase (AChE) is the one of the most investigated mechanisms of action in EOs. However, EOs are rather weak inhibitors of AChE. Another proposed mechanism of EO action is a positive allosteric modulation of GABA receptors (GABArs). There are several papers that prove the potentiation of GABA effect on mammalian receptors induced by EOs. In contrast, there is lack of any data concerning the binding of EO components in insects GABArs. In insects, EOs act also via the octopaminergic system. Available data show that EOs can increase the level of both cAMP and calcium in nervous cells. Moreover, some EO components compete with octopamine in binding to its receptor. Electrophysiological experiments performed on Periplaneta americana have shown similarity in the action of EO components and octopamine. This suggests that EOs can modify neuron activity by octopamine receptors. A multitude of potential targets in the insect nervous system makes EO components interesting candidates for bio-insecticides.

Electromagnetic fields (EMFs) are present throughout the modern world and are derived from many man-made sources including overhead transmission lines. The risks of extremely-low frequency (ELF) electromagnetic fields are particularly poorly understood especially at high field strengths as they are rarely encountered at ground level. Flying insects, however, can approach close to high field strength transmission lines prompting the question as to how these high levels of exposure affect behaviour and physiology. Here we utilise the accessible nervous system of the locust to ask how exposure to high levels of ELF EMF impact at multiple levels. We show that exposure to ELF EMFs above 4 mT leads to reduced walking. Moreover, intracellular recordings from an identified motor neuron, the fast extensor tibiae motor neuron, show increased spike latency and a broadening of its spike in exposed animals. In addition, hind leg kick force, produced by stimulating the extensor tibiae muscle, was reduced following exposure, while stress-protein levels (Hsp70) increased. Together these results suggest that ELF EMF exposure has the capacity to cause dramatic effects from behaviour to physiology and protein expression, and this study lays the foundation to explore the ecological significance of these effects in other flying insects.

Based on these data we conclude that exposure duration (dose-response) plays a significant role in the immune response, specifically at the cellular level. While single 24 h-lasting exposure provoked changes that indicate an immune alarm stimulation, under the conditions which are typical for therapeutic use of ELF-MFs (repeated short daily exposure) the immune potentially harmful response has not been observed.

The aim of this work is to present the current knowledge about the possible participation of electromagnetic fields in the occurrence and also in treatment of neurodegenerative diseases. The literature data indicate both the negative and positive effects of electromagnetic fields and not allow to draw unambiguous conclusions. Undoubtedly, the topic is still open and needs further intensive research to finally assess the mechanism of action of the electromagnetic field on neurodegenerative diseases. Streszczenie. Celem niniejszej pracy jest przedstawienie aktualnej wiedzy o możliwym udziale pól elektromagnetycznych w występowaniu oraz w leczeniu chorób neurodegeneracyjnych. Dane literaturowe wskazują zarówno na negatywny, jak i pozytywny wpływ pól elektromagnetycznych i nie pozwalają na wyciągnięcie jednoznacznych wniosków. Niewątpliwie temat jest nadal otwarty i wymaga dalszych intensywnych badań, aby ostatecznie ocenić mechanizm działania pola elektromagnetycznego na choroby neurodegeneracyjne. (Pola elektromagnetyczne i choroby neurodegeneracyjne)

StreszczenieWstęp: Badania nad oddziaływaniem pola elektromagnetycznego na organizmy żywe są istotnym elementem badań biofizycznych. Są to badania interdyscyplinarne, łączące nierozerwalnie biologię i medycynę z techniką wytwarzania i pomiaru pól elektromagnetycznych. Celem pracy jest analiza układów ekspozycyjnych pola magnetycznego ekstremalnie niskich częstotliwości w badaniach biomedycznych oraz metod pomiarów parametrów pola. Materiał i metody: Badaniom poddano 2 najpopularniejsze układy ekspozycyjne pola magnetycznego niskiej częstotliwości -solenoid i cewki Helmholtza. Przeprowadzono analizy teoretyczne i weryfikację pomiarową rozkładu pola w układach w celu oceny jednorodności pola. Zbadano również czynniki dodatkowe wpływające na ocenę biologicznych efektów ekspozycji -drgania i zmiany temperatury. Wyniki: Na podstawie przeprowadzonych badań przedstawiono analizę porównawczą solenoidów i cewek Helmholtza jako układów ekspozycyjnych pola magnetycznego oraz sformułowano wnioski dotyczące opisu warunków ekspozycji na pole magnetyczne. Wnioski: Autorzy podkreślają znaczenie świadomego doboru warunków ekspozycji i ich jednoznacznego opisu. Jest to podstawą odtworzenia warunków doświadczalnych oraz weryfikacji uzyskanych wyników. Med. Pr. 2015;66(2):185-197 Słowa kluczowe: pole elektromagnetyczne, układ ekspozycyjny, metrologia pola elektromagnetycznego, solenoid, cewki Helmholtza, bioelektromagnetyzm Abstract Background: Experiments on the electromagnetic field influence on organisms are an important part of biophysical studies. It is an interdisciplinary research spanning biology and medicine with the engineering in generation and measurement of electromagnetic fields. The aim of the study consists in the analysis of parameters estimations and measurements of extremely low frequency magnetic field (ELF MF) as well as exposure systems parameters in biomedical research. Material and Methods: Experiments were performed on 2 most popular low magnetic field exposure systems: the solenoid and Helmholtz coils. A theoretical analysis and a measurement verification of the magnetic field distribution inside the systems were carried out to evaluate the homogeneity of the magnetic field. Additional factors, vibrations and temperature changes, affecting the assessment of the biological effects of magnetic field exposure were also examined. Results: Based on the study results, a comparative analysis of solenoids and Helmholtz coils as the magnetic field exposure systems was presented. Proposals for the description of magnetic field exposure were also formulated. Conclusions: The authors emphasize the importance of a conscious choice of exposure conditions and their explicit description. These are fundamental requirements for both the reproduction of experimental conditions and the verification of results. Med Pr 2015;66(2): [185][186][187][188][189][190][191][192][193][194][195][196][197]

Exposure to electromagnetic field (EMF) induces physiological changes in organism that are observed at different levels—from biochemical processes to behavior. In this study, we evaluated the effect of EMF exposure (50 Hz, 7 mT) on cockroach’s response to noxious heat, measured as the latency to escape from high ambient temperature. We also measured the levels of lipid peroxidation and glutathione content as markers of oxidative balance in cockroaches exposed to EMF. Our results showed that exposure to EMF for 24, 72 h and 7 days significantly increases the latency to escape from noxious heat. Malondialdehyde (MDA) levels increased significantly after 24-h EMF exposure and remained elevated up to 7 days of exposure. Glutathione levels significantly declined in cockroaches exposed to EMF for 7 days. These results demonstrate that EMF exposure is a considerable stress factor that affects oxidative state and heat perception in American cockroach.

The abrupt disappearance of the bees that pollinate crops is a significant subject of recent study. One theory points to the development of telecommunications technology and an increasing number of electromagnetic field sources as a possible cause of the phenomenon.This paper presents the results of preliminary studies of honeybee exposure to extremely low frequency electromagnetic field (50 Hz; 1 mT, 7 mT) Streszczenie. Nagłe znikanie pszczół, które zapylają uprawy, jest jednym z istotnych tematów ostatnich badań. Jedna z teorii wskazuje na rozwój telekomunikacji i zwiększenie liczby źródeł pola elektromagnetycznego jako możliwą przyczynę tego zjawiska. Artykuł prezentuje wyniki wstępnych badań nad ekspozycję pszczół miodnych na pole elektromagnetyczne o wyjątkowo niskiej częstotliwości (50 Hz; 1 mT 7 mT) (Pola elektromagnetyczne i zespół masowego ginięcia pszczoły miodnej).

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