The comparative analysis of influence of low-intensity electromagnetic fields on the processes of self-assembly of core histones H2A and H2B was performed. To study the self-organization of histones H2A and H2B used the method of wedge dehydration. Image-facies analysis included their qualitative characteristics, as well as the calculation of quantitative indicators, followed by statistical analysis. It was established that electromagnetic radiation changes the self-organization of histones. At the same time, there is a differential sensitivity of histones to the influence of the red laser and UHF irradiation. Established fact influence of low-intensity electromagnetic fields on the process of self-assembly of core histones offers the prospect of further study of the biological effects of these types of radiation.
The analysis of influence of low-intensity electromagnetic field on the processes of self-assembly of core histones H3.2 and H4 was performed. To study the self-organization of histones H3.2 and H4 used the method of wedge dehydration. Image-facies analysis included their qualitative characteristics, as well as the calculation of quantitative indicators, followed by statistical analysis. It was established that UHF-Radiation (1GHz, 0,1 μW/cm2, 10 min) significantly modifies the process of self-assembly of core histones H3.2 and H4. Established fact influence of low-intensity electromagnetic field on the process of self-assembly of core histones offers the prospect of further study of the biological effects of this type of radiation.
The aim of the present work was to investigate the ability of inhibiting the growth of various strains of Staphylococcus aureus by low-intensity laser light. As object of research used methicillin-sensitive and methicillinresistant strains of Staphylococcus aureus. For irradiation was used a semiconductor laser, which generates linearly polarized radiation of the red spectral region (λ - 660 nm). Power density was 100 mW/cm2, irradiation time – 5, 10, 15 and 30 min, heat density respectively 30, 60, 90, and 180 J/cm2. It was established that low-intensity laser radiation has an inhibitory effect on growth of colonies of both methicillin-sensitive and methicillin-resistant strains of Staphylococcus aureus. But resistant strain is more sensitive to the action of red light, as the bacteriostatic effect is detected at the lower doses.
Analysis of the influence of low-intensity electromagnetic field on the processes of self-assembly of the lincer histone H1 was performed. To study used a wedge dehydration method. Image-analysis of facies included their qualitative characteristics and calculation of quantitative parameters with subsequent statistical processing. It was established that UHF-Radiation (1GHz, 0,1 μW/cm2 , 10 min) significantly modifies the process of self-organization of lincer histone, which determines the possibility of the involvement of the genetic apparatus of the cell in the effects of this type of radiation on biological objects.
The influence of red laser irradiation on the growth of colonies of Staphylococcus aureus and photodynamic effect of the photosensitizer Photoditazine were performed. It was established that the emission of red laser light caused an inhibition of bacterial growth. This effect on standard strain of Staphylococcus aureus was evident only when relatively high doses of radiation (180 j/cm2). Photosensitivity of the methicillin-resistant strains was much higher: bacteriostatic effect of red light was observed already at the dose of 60 j/cm2 . Pre-treatment of bacterial cells by Photoditazine significantly enhances the inhibitory effect of the laser light.
The influence of low-intensity electromagnetic radiation on the process of self-assembly, spectral-fluorescent characteristics and lethal effect of bacterial lipopolysaccharide (endotoxin) was performed. A solution of bacterial lipopolysaccharide exposed to electromagnetic waves with a frequency of 1 GHz, the power density of 0.1 μW/cm2 for 10 min. In experiments on a large group of control and irradiated mice, a comparative analysis of the estimated lethal dose of endotoxin was performed. It was proved that UHF radiation of certain parameters reduces the lethal effects of bacterial lipopolysaccharide on 26%.
KEYWORDS: Biomedical optics, Medical devices, Pathogens, Bacteria, In vitro testing, Scanning electron microscopy, Microorganisms, Crystals, Medical research, Electron microscopy
The current study was designed to investigate the dynamics of microbial biofilm-formation in standard and clinical strains of uropathogenic Escherichia coli (UPEC), using spectrophotometric and electron microscopic methods. For achieving this goal, three E. coli strains were used (one standard and two clinical). These isolates differ in the existence of fimH virulence gene. The process involved the using of electron microscopy and immunological microtitration plates under in vitro conditions for 96 hours. We found that standard and clinical strains of E. coli were capable of forming a microbial biofilm in vitro, with a higher intensity related to the clinical strain E. coli 245. The using of scanning electron microscopy confirmed the obtained results. The combined use of different optical methods gives a complete characterization of film-forming ability of pathogenic microorganisms.
Analysis of the influence of red laser irradiation on the processes of self-assembly of the core histones H2A and H2B was performed using a wedge dehydration method. Image-analysis of facies included their qualitative characteristics and calculation of quantitative parameters with subsequent statistical processing. It was established that linearly polarized red laser light (λ - 660 nm, 1 J/cm2) significantly modified the process of self-assembly of core histone H2B, whereas the structure of the facies of H2A histone changed to a lesser extent. Histones were used in the form of aqueous salt solutions. The effect of red light seems to result from the formation of singlet oxygen by direct laser excitation of molecular oxygen.
The influence of red laser irradiation on the growth of colonies of methicillin-resistant strain of Staphylococcus aureus and photodynamic effects of the photosensitizers Photoditazine and Dimegin were performed. It was established that the red semiconductor laser (λ - 660 nm, 100 mW/cm2) at 10-, 15- and 30-mins exposure, has a direct bacteriostatic action on the growth of S. aureus. Pre-treatment of bacterial cells by Photoditazine significantly enhances the inhibitory effect. The photosensitizing action of Dimegin does not appear at influence on methicillin-resistant S. aureus.
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