Platelet activation plays a key role in the pathogenesis of cardiovascular complications in patients with coronary and cerebrovascular ischemic disease. The most important task in the treatment and prevention such complications is the complete suppression of platelet activity. Inhibition of platelet aggregation is currently a key therapeutic approach in the treatment and prevention of cardiovascular atherosclerotic origin. The development of new and more effective methods for prediction of the response of patients to antiplatelet therapy and its subsequent correction appears to be the most important task of modern physics, biophysics, and medicine. Platelets obtained from patient specimens have been investigated by Surface-enhanced Raman spectroscopy (SERS) with the diode-pumped solid-state laser (λ = 532 nm) on Au/Ti rough surfaces. As a result, a set of optimal experimental parameters for platelets discrimination have been determined. Platelet spectral data for healthy volunteers, healthy volunteers on antiplatelet therapy and individuals with cardiovascular pathology on antiplatelet therapy have been analyzed. We suggest that the obtained results allow the usage of the SERS as a diagnostic tool for determination of both inhibition of platelet aggregation and its structure conformation.

The article describes the results of finite-difference time-domain (FDTD) mathematical modeling of electric field strength distribution near the gold laser-induced periodic surface structures (LIPSS). Both theoretical and experimental results have been described for two fabricated morphologies: round «hill-like» and grating structures. The structures were fabricated by using a femtosecond Yb-fiber laser with a wavelength of λ=1032 nm, pulse duration τ=280 fs, and repetition rate υ=25 kHz. Morphological properties of the surfaces have been investigated by means of scanning electron microscopy (SEM). The plasmonic activity was analyzed by means of the surface-enhanced Raman spectroscopy (SERS) technique. FDTD-calculated electric field values were converted into the electromagnetic field enhancement coefficient and the theoretical SERS intensity. The prospects of the theoretical approach for LIPSS to evaluate optimal field amplification and light scattering parameters has been shown. The presented approach could be applied as a basis for performing the methods of controlled synthesis for LIPPS.

Biologically active substances from microalgae can exhibit antioxidant, immunostimulating, antibacterial, antiviral, antitumor, antihypertensive, regenerative, and neuroprotective effects. Lipid complexes of microalgae Chlorella vulgaris and Arthrospira platensis exhibit antibacterial activity and inhibit the growth of the Gram-positive strain Bacillus subtilis; the maximum zone of inhibition is 0.7 ± 0.03 cm at all concentrations. The carbohydrate-containing complex of C. vulgaris exhibits antibacterial activity, inhibits the growth of the Gram-positive strain B. subtilis, Bacillus pumilus; the maximum zone of inhibition is 3.5 ± 0.17 cm at all concentrations considered. The carbohydrate complex of A. platensis has antimicrobial activity against the Gram-negative strain of Escherichia coli at all concentrations, and the zone of inhibition is 2.0–3.0 cm. The presence of mythelenic, carbonyl groups, ester bonds between fatty acids and glycerol in lipid molecules, the stretching vibration of the phosphate group PO2, neutral lipids, glyco- and phospholipids, and unsaturated fatty acids, such as γ-linolenic, was revealed using FTIR spectra. Spectral peaks characteristic of saccharides were found, and there were cellulose and starch absorption bands, pyranose rings, and phenolic compounds. Both algae in this study had phenolic and alcohol components, which had high antibacterial activity. Microalgae can be used as biologically active food additives and/or as an alternative to antibiotic feed in animal husbandry due to their antibacterial properties.

Abstract This work presents the dependences of the absorption intensity of the acid-soluble chitosan biopolymer films in the infrared (IR) region of the spectrum on the concentrations of silver and gold nanoparticles (NPs) of different morphologies. The interaction mechanisms in the vibrational spectra overlapping area of the silver NPs and chitosan molecules (2500–3500 cm−1) were observed. The influence of the metal NPs on the dipole moments of the OH-, NH3+- and CH-chitosan molecule group oscillations was established. This interaction leads to a linear increase of the IR absorption intensity with an increase of the silver nanoparticle concentration, synthesized by the citrate and borohydride methods. The presence of silver and gold ablative NPs in the chitosan films demonstrates the IR absorption intensity exponential decrease with the metal NPs’ concentrations.

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We have been searching for new photosensitizers (PS) for photodynamic therapy (PDT) of cancer based on extracts from Amazonian plants since 2009. In this paper, we demonstrate that, under certain conditions, the extract from fruits of the Amazonian palm Euterpe oleraceae (popular name Açaí) can serve as a PS for PDT treatment of murine breast cancer cells (4T1 cell line). We have been first to show directly that the photodynamic effect of plant PS is due to singlet oxygen.

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