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\nPlain Language SummaryThe effect of non-ionizing millimeter range electromagnetic waves (MM EMW) (30–300 GHz) on the bovine serum albumin (BSA) interaction peculiarities with acridine orange (AO) has been studied in vitro. The frequencies 41.8 and 50.3 GHz were chosen, since the first one is nonresonant frequency for the water, while the second one is resonant for water. The binding constant and number of binding sites were calculated at both irradiation presence and absence. AO was revealed to bind to BSA, while after the protein irradiation the interaction force strengthens. However, it was also shown that there are differences of the interaction parameters while irradiating by 41.8 or 50.3 GHz. AO binds to BSA, irradiated by MM EMW with the frequency 41.8 GHz much more weaker, than to that, irradiated by MM EMW with the frequency 50.3 GHz.The manuscript is devoted to the study of the effect of millimeter range electromagnetic waves with the frequencies 41.8 and 50.3 GHz on the model biological system, being on molecular level of organization. Nowadays millimeter range electromagnetic waves compose a significant part of electromagnetic pollution in the environment and affect biological material, besides these waves are used in extremely high frequencies-therapy ((30–300 GHz), which are millimeter range electromagnetic waves (1–10 mm)). On the other hand, the problem of their effect mechanism is mainly connected to water, since the resonant frequencies for water molecules are in the interval of millimeter waves. In the present study, as such biological molecule, the bovine serum albumin has been chosen, which interacts with acridine orange. Serum albumins are known to carry and transport various endogenous and exogenous agents, including drugs throughout circulatory system. In turn, acridine orange has been extensively used for biological staining to differentiate DNA from RNA by fluorescence emission for years, Nowadays, it is considered as a promising agent for antitumorous treatment and diagnosis.The data obtained show that the interaction between bovine serum albumin and acridine orange changes, when the solution of albumin is irradiated by the millimeter waves with the frequencies 41.8 and 50.3 GHz. However, the interaction alteration depends on the frequency as well. Thus, the irradiation with the frequency 41.8 GHz makes insignificant changes, while that with the frequency 50.3 GHz induces significant changes of measured parameters. The studies were conducted by absorption, fluorescence and CD spectroscopy methods. [ABSTRACT FROM AUTHOR]

In this work the study of the effect of millimeter range electromagnetic waves (MM EMW) on the complexes of human serum albumin (HSA) with methyl violet (MV) has been carried out at the different frequencies, using the methods of fluorescence and thermodenaturation. It was shown that MV binds to HSA, forming a complex, and increasing of the intensity of the protein own fluorescence takes place, meanwhile the stabilization of HSA increases. MM EMW irradiation of HSA by various frequencies invokes additional changes in the protein structure. Thus, at the protein irradiation with the frequency 41.8 GHz the protein stabilization increases as well as hydrophobicity around the tryptophan rises, while at the irradiation with 51.8 GHz the stabilization is expressed less and the hydrophobicity enhancement around the tryptophan can be neglected. [ABSTRACT FROM AUTHOR]

The effect of electromagnetic waves of the millimeter region on the conformation and fluorescence characteristics of human serum albumin was studied. It is shown that the irradiation of the albumin solution leads to an increase of the fluorescence intensity depending on the duration of irradiation. At an irradiation frequency of 48 GHz the fluorescence intensity of albumin hardly changes at all, while at 41.8 and 51.8 GHz it increases. It is also shown that when the irradiation frequency is 51.8 GHz, the intensity of the albumin solution fluorescence increases with increase of the irradiation time. [ABSTRACT FROM AUTHOR]

In present work the effect of millimeter electromagnetic radiation on the surface charge density of rat blood erythrocytes has been studied. The experiments were carried out irradiating suspension of erythrocytes of rat blood by different frequencies. It was shown that in the case of the irradiation by water non-resonant as well as resonant frequencies the value of studying parameter decreases compared to control samples. In the case of the irradiation by water resonant frequency the decrease of the value of studying parameter is more pronounced. In both cases a reliable changes of the surface charge density value of rat blood erythrocytes take place. [ABSTRACT FROM AUTHOR]

We propose a procedure for mathematical treatment of the spectra of complexes between ligands and DNA, which allows us to determine the position of the isosbestic point with high precision. As a specific example, we consider the absorption spectra of ethidium bromide complexes titrated against a DNA solution. As a result of using the method, besides the main type of binding we have identified the appearance of additional types of binding between the ethidium bromide and DNA. [ABSTRACT FROM AUTHOR]

Thermostability of mitoxantrone complexes with DNA of sarcoma 45 and healthy rat liver earlier irradiated by non-thermal (50 µW/cm²) resonant (64.5 GHz and 50.3 GHz) and non-resonant (48.3 GHz) of water hexagonal structure frequencies millimeter electromagnetic waves (MEW) oscillations has been studied. It was shown that at irradiation of solutions by resonant with water hexagonalstructurefrequencies, a dehydration of nucleotides of irradiated DNA and Na+ ions existing in the solution occurs. At relatively low concentrations of mitoxantrone it results in decreasing of thermostability of complexes with DNA, moreover this change is more pronounced at complex-formation with DNA from sarcoma 45 tumor. It was shown that the thermostability of the radiated by non-resonant frequents DNA-MTX complexes does not change. [ABSTRACT FROM AUTHOR]

The effect of electromagnetic waves of extremely high frequencies (EMW EHF) on the blood plasma surface tension coefficient and the albumin denaturation parameters was studied. It was shown that blood plasma irradiation, taken from rats, results in significant increasing of its surface tension coefficient value compared to that of non- irradiated samples. It was also shown that a reliable difference between irradiated samples by 41.8 GHz and 51.8 GHz frequencies was not noticed. Albumin solution denaturation parameters under to irradiation were studied. It was shown that protein denaturation curve shifting to high temperature region occurs which means that stabilization of protein structure takes place. It was shown that protein denaturation curve shifts to high temperature region, which means that stabilization of protein structure, takes place. [ABSTRACT FROM AUTHOR]

Aim. To investigate the thermodynamic characteristics of complexes of calf thymus double-stranded DNA with methylene blue (MB), ethidium bromide (EtBr) and Hoechst 33258 (H33258). Methods. The binding of MB with double-stranded DNA was observed by UV-melting method. Results. Several types of MB binding to DNAintercalating, semi-intercalating and electrostatic with DNA phosphate backbone, have been revealed at low concentrations of Na+ (2 mM). At high concentrations of cations and low ratios of rb = [ligand]/[DNA] (⩽0.05), the molecules of ligand semi-intercalate into the space between adjacent bases. At higher concentrations of ligand the main mode becomes electrostatic binding of MB to DNA phosphate groups. Conclusions. The comparison of thermodynamic characteristics of DNA-MB complexes with those of EtBr and H33258 indicates that there is more than one mode of binding ligands to DNA: besides nonspecific, external electrostatic binding with phosphate groups, intercalation and semi-intercalation modes of interaction coexist. [ABSTRACT FROM AUTHOR]

We have used absorption and fl uorimetric methods to study the interaction between methylene blue (MB) and calfthymus DNA. Based on Scatchard analysis of the experimental data, we plotted the methylene blue-DNA binding curve. This curve consists of two linear sections, which indicates two types of interaction, for which we determined the constants K and the number of binding sites n for binding of this ligand to DNA. Comparison of the data obtained with analogous values found for interaction between ethidium bromide and DNA allowed us to conclude that there are two modes of interaction between methylene blue and DNA: strong binding (semi-intercalation) and weak binding (electrostatic). [ABSTRACT FROM AUTHOR]