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1.
Chem Biol Interact ; 357: 109880, 2022 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-35271822

RESUMO

Sosnovsky's hogweed, Heracleum sosnowskyi has a high photosensitizing ability. Although Sosnovsky's hogweed is known as a poisonous plant, its chemical composition and phototoxicity are poorly studied. We analyzed the chemical composition of the Sosnovsky's hogweed juice that grew in natural conditions. It was found that the content of 8-methoxypsoralen in the juice is 1332.7 mg/L, and that of 5-methoxypsoralen is 34.2 mg/L. We have developed and analyzed liposomes containing furanocoumarins of Sosnovsky's hogweed juice and studied their photocytotoxicity in L929 mouse fibroblast cell culture. It was found that liposomes containing furanocoumarins of Sosnovsky's hogweed juice are more toxic for L929 cells in comparison with liposomal forms of pure substances 8-methoxypsoralen and 5-methoxypsoralen. It was found that when exposed to UV radiation at 365 nm at a dose of 22.2 J/cm2, the liposomal form of furanocoumarins Sosnovsky's hogweed is 3 times more toxic to L929 cells than in the dark. It was found that the photocytotoxic effect of liposomal furanocoumarins Sosnovsky's hogweed is a strongly stimulation of apoptosis.The data obtained suggest that the raw material of Sosnovsky's hogweed claims to be a source of furanocoumarins, and the liposomal form, given the hydrophobic properties of furanocoumarins, is very suitable for creating a phototherapeutic drug.


Assuntos
Furocumarinas , Heracleum , Animais , Furocumarinas/toxicidade , Heracleum/química , Lipossomos , Metoxaleno , Camundongos , Raios Ultravioleta
2.
J Acoust Soc Am ; 146(3): 1968, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31590497

RESUMO

Sound propagation in an area of shallow sea with circular isobaths and the bottom depth increasing towards their curvature center is considered. Such an area could be part of a bay, a lagoon, or a lake with bowl-like bottom relief. The possible formation of whispering gallery waves localized in the vicinity of curved isobaths is considered. Simple criteria for the formation of such whispering gallery due to horizontal refraction are derived; their transverse modal structure is described analytically in terms of Bessel functions and using the Wentzel-Kramers-Brillouin-Jeffreys approximation. The corresponding azimuthal wavenumbers and radial mode functions are computed. Dispersion of such waves is also investigated, and the possibility of their experimental observation is discussed.

3.
J Acoust Soc Am ; 146(3): 1946, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31590495

RESUMO

A wide class of three-dimensional sound propagation problems in shallow water where the bathymetry can be locally approximated by a parametric quadratic function is considered. Relevant examples of such bathymetry functions include underwater canyons and ridges. Asymptotic solution for this class of problems is derived under the adiabaticity assumption. The solution is based on mode parabolic equation theory and group-theoretical disentanglement formulas for operator exponentials. Two examples are considered (a ridge and a bottom with quadratic slope), and respective wavefront geometry is studied.

4.
Polymers (Basel) ; 11(5)2019 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-31130638

RESUMO

This study looked into the synthesis and study of Dextrane Sulfate-Doxorubicin Nanoparticles (DS-Dox NP) that are sensitive to amylase and show anticoagulant properties. The particles were obtained by the method of solvent replacement. They had a size of 305 ± 58 nm, with a mass ratio of DS:Dox = 3.3:1. On heating to 37 °C, the release of Dox from the particles was equal to 24.2% of the drug contained. In the presence of amylase, this ratio had increased to 42.1%. The study of the biological activity of the particles included an assessment of the cytotoxicity and the effect on hemostasis and antitumor activity. In a study of cytotoxicity on the L929 cell culture, it was found that the synthesized particles had less toxicity, compared to free doxorubicin. However, in the presence of amylase, their cytotoxicity was higher than the traditional forms of the drug. In a study of the effect of DS-Dox NP on hemostasis, it was found that the particles had a heparin-like anticoagulant effect. Antitumor activity was studied on the model of ascitic Zaidel hepatoma in rats. The frequency of complete cure in animals treated with the DS-Dox nanoparticles was higher, compared to animals receiving the traditional form of the drug.

5.
Molecules ; 23(5)2018 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-29757999

RESUMO

Betulin-3,28-diphosphate (BDP) obtained by phosphorylation of betulin using POCl3 has two main structural forms-BDP-1 and BDP-2-which differ in ethanol solubility, melting point, FTIR spectra, thermoanalytical characteristics and biological activity. Betulin-3,28-diphosphate and its sodium salt (Na-BDP) were characterized using 13C and 31P-NMR spectra, powder XRD experiments, as well as differential scanning calorimetry (DSC) and thermogravimetric analysis (TG) methods. The exo-effects at 193 ± 8 °C for ethanol soluble BDP-1 samples (-19.7 ± 0.2 kJ∙mol-1) were about three times less than for ethanol insoluble BDP-2 samples f (-70.5 ± 0.7 kJ∙mol-1). The DSC curves of Na-BDP-1 and Na-BDP-2 characterized the endo-effects having a maximum at 95⁻112 °C. Water-soluble Na-BDP-1 was obtained as needle-like crystals, unlike poorly crystalline Na-BDP-2, whereas BDP-1 and BDP-2 aged with time and were isolated as amorphous substances. In vitro experiments on rats showed that compared to the control, Na-BDP-1 increased catalase and SOD activity and improved energy metabolism more effectively than Na-BDP-2.


Assuntos
Difosfatos/química , Triterpenos/química , Triterpenos/farmacologia , Varredura Diferencial de Calorimetria , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier , Triterpenos/síntese química , Água , Difração de Raios X
6.
J Acoust Soc Am ; 139(3): 1343-52, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27036271

RESUMO

A problem of sound propagation in a shallow-water waveguide with a weakly sloping penetrable bottom is considered. The adiabatic mode parabolic equations are used to approximate the solution of the three-dimensional (3D) Helmholtz equation by modal decomposition of the acoustic pressure field. The mode amplitudes satisfy parabolic equations that admit analytical solutions in the special case of the 3D wedge. Using the analytical formula for modal amplitudes, an explicit and remarkably simple expression for the acoustic pressure in the wedge is obtained. The proposed solution is validated by the comparison with a solution of the 3D penetrable wedge problem obtained using a fully 3D parabolic equation that includes a leading-order cross term correction.

7.
J Acoust Soc Am ; 136(4): EL281-7, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25324111

RESUMO

The problem of the sound propagation in shallow-water waveguide with a seabottom featuring canyon-type inhomogeneity of a specific form is considered. The sound pressure in such waveguide is represented in a form of modal expansion and the equations for modal coefficients are derived. In case of a single-mode adiabatic propagation, it is possible to neglect the mode interaction and omit the coupling terms in these equations. The uncoupled equation for the mode amplitude admits an explicit analytical solution via the separation of variables.

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