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This work deals with the problem of synthesis and investigation of the structure and properties of polymer calcium phosphate biopolymer suspensions, their use to obtain film samples containing drugs, and the study of the kinetics of drug release from the polymer matrix. The compositions were synthesized using the method of mechano-acoustic activation. The use of the mechano-acoustic activation technique and ultrasonic dispersion makes it possible to synthesize calcium phosphate compounds in aqueous media, to modify the synthesized products with drugs and bioactive substances, and to form biocompositions for the manufacture of bone implants.

H2O absorption lines broadened by air pressure were recorded in the 5900–6100-cm−1 spectral region with the use of a Bruker IFS 125 HR spectrometer. The intensities and broadening and shift coefficients of H2O absorption lines are determined for the Voigt profile and the modified Voigt profile which takes into account the dependence of the broadening on the speed of the colliding molecules. The atmospheric transmission is calculated with the use of H2O line parameters from different versions of the HITRAN and GEISA spectroscopic databases and our new data. Model spectra are compared with atmospheric solar spectra measured with a ground-based Fourier spectrometer. It is shown that the use of our new data on H2O absorption line parameters improves the agreement between the model and measured atmospheric spectra.

The effect of the partial substitution of M = Ti, V, Cr, Zr, and Nb for Fe in the Pr2Fe17 and Tm2Fe17 alloys on their structural, magnetic, and magnetocaloric properties have been studied using magnetic measurements, X-ray, and neutron diffraction. The character of substitution of Ti, V, Cr, Zr, and Nb atoms for Fe atoms, along with the differences in atomic radii of these elements, substantially affects variations of the lattice parameters and Curie temperatures of the Tm2Fe17 – xMx and Pr2Fe17 – xMx alloys. The Curie temperature of all the substituted alloys increases; the rate of the increase in the Curie temperature of the Tm2Fe17 – xMx alloys is twice that of the Pr2Fe17 – xMx alloys. The magnetic moment of iron atoms MFe and the magnetocaloric effect –ΔSM decrease for the substituted Tm2Fe17 – xMx and Pr2Fe17 – xMx alloys and become close in the case of all M.

The objective of this study was screening of ommochromes from the compound eyes of insects and comparison of their antioxidant properties. Ommochromes were isolated in preparative quantities from insects of five different families: Stratiomyidae, Sphingidae, Blaberidae, Acrididae, and Tenebrionidae. The yield of ommochromes (dry pigment weight) was 0.9-5.4% of tissue wet weight depending on the insect species. Isolated pigments were analyzed by high-performance liquid chromatography and represented a mixture of several ommochromes of the ommatin series. The isolated ommochromes displayed a pronounced fluorescence with the emission maxima at 435-450 nm and 520-535 nm; furthermore, the emission intensity increased significantly upon ommochrome oxidation with hydrogen peroxide. The ommochromes produced a stable EPR signal consisting of a singlet line with g = 2.0045-2.0048, width of 1.20-1.27 mT, and high concentration of paramagnetic centers (> 1017 spin/g dry weight). All the investigated ommochromes demonstrated high antiradical activity measured from the degree of chemiluminescence quenching in a model system containing luminol, hemoglobin, and hydrogen peroxide. The ommochromes strongly inhibited peroxidation of the photoreceptor cell outer segments induced by visible light in the presence of lipofuscin granules from the human retinal pigment epithelium, as well as suppressed iron/ascorbate-mediated lipid peroxidation. The obtained results are important for understanding the biological functions of ommochromes in invertebrates and identifying invertebrate species that could be used as efficient sources of ommochromes for pharmacological preparations to prevent and treat pathologies associated with the oxidative stress development.

A global analysis of the fluorescence decay kinetics of a chloroform extract of lipofuscin granules from the retinal pigment epithelium cells of human cadaver eyes is performed. The analysis makes it possible to reconstruct the individual fluorescence properties of four groups of fluorophores belonging to bisretinoids and the products of their photooxidation and photodegradation. The characteristic fluorescence lifetimes are correlated with the spectral characteristics of the indicated fluorophore groups using the averaged spectral and kinetic characteristics of the chloroform extract.

Fluorescence and chromatographic analysis of bisretinoids from the retina and retinal pigment epithelium of mouse eyes was carried out before and after exposure to accelerated protons in the Bragg peak. It has been shown that ionizing radiation at doses of 1–4 Gy leads to a shift in the short-wave region of the maximum of the fluorescence spectrum in the chloroform extract obtained from both the retinal pigment epithelium and the retina. Chromatographic analysis of these extracts has shown a change in the relative content of individual bisretinoids. The obtained spectral and chromatographic data indicate that the exposure of mice to accelerated protons in the Bragg peak at doses of 1–4 Gy leads to radiation oxidation of bisretinoids in eye tissues.

The fluorescence lifetimes of lipofuscin fluorophores contained in chloroform extracts from retinal pigment epithelium (RPE) of human cadaver eyes without signs of pathology were evaluated by single photon counting. The comparison of fluorescence lifetimes of N-retinylidene-N-retinylethanolamine (A2E) and its photooxidation and photodegradation products has been carried out. It was shown that the contribution of A2E to the total fluorescence of chloroform extract from lipofuscin granules is not major. The results are important for the improvement of noninvasive diagnostic method of degenerative diseases of the retina and RPE-fundus autofluorescence (FAF).

Integral parameters of bacterial lipopolysaccharide concentration and antiendotoxin immunity activity were determined in the blood serum of subjects with two extreme variants of eating disorders: obesity and anorexia nervosa (in its clinical model, long-term starvation). The results of the study showed that obese patients had initially higher endotoxin concentrations (2.41 ± 0.11 vs 1.13 ± 0.05 EU/mL in the control), which significantly decreased as a result taking a course of orlistat or after starvation (for no longer than 20 days) (to 1.34 ± 0.04 and 1.01 ± 0.09 EU/mL, respectively). The decrease in the endotoxin serum level was associated with an increase in the concentration of high-density lipoproteins (HDLs) and a decrease in the concentration of low-density lipoproteins (LDLs). This allowed us to assume that the complex of the latter with the endotoxin is the LDL fraction that may function as a depot of the hydrophobic form of the lipopolysaccharide molecule in the bloodstream. Long-term starvation (starting from day 20) led to the appearance of symptoms characteristic of septic states, which was preceded by a twofold increase in the concentration of the endotoxin and antibodies against the enterobacterial common antigen and subsequent increase in the level of anti-glycolipid antibodies (from 133.2 ± 2.6 to 355.6 ± 15.0 optical density arbitrary units) starting from day 25–27 of starvation, which is characteristic for the initial phase of the systemic inflammatory response syndrome.

Reactions of copper(II) carboxylates with dibenzyl ether (DBE) gave binuclear complexes of the formula Cu2(μ-OOCR)4(DBE)2 (R = But, Ph, and CF3). The complexes were characterized by X-ray diffraction. The axial positions in the lantern-type dimer are occupied by the coordinated DBE molecules. The complexes seem to be analogs of intermediate catalysts for the oxidation of DBE with atmospheric oxygen in the presence of transition metal complexes. When stored in air, the complex Cu2(μ-OOCPh)4(DBE)2 underwent oxidation into Cu2(μ-OOCPh)4(HOOCPh)2, which was characterized by X-ray diffraction. The geometry of its framework is similar; the structure is stabilized by intramolecular H bonds between the axially oriented benzoic acid molecules and the adjacent bridging benzoate anions.

A room-temperature reaction of cupric acetate dihydrate with 3,5-bis(trifluoromethyl)pyrazole ((CF3)2pzH) in chloroform in the presence of triethylamine gave a complex of the formula [Cu2(μ-(CF3)2pz)2(μ-OH2)(OC(Me)OHNEt3)(OH2)(HCCl3)(OOCMe)(μ-OOCMe)]2 (2). Heating of this complex at 180°C in dibenzyl ether (DBE) in air yielded the tetranuclear pyrazolate-benzoate cluster Cu4(μ4-OH)(μ-(CF3)2pz)4(μ-OOCPh)2(μ-OH)2(OH2)(Et3NH)[O(CH2Ph)2]2. It was suggested that such complexes can be intermediates in the liquid-phase oxidation of DBE with atmospheric oxygen in the presence of copper complexes containing pyrazolate bridges.

Deprotonation reactions of pyrazole and its analogs by aqueous copper acetate in benzene at room temperature in the presence of triethylamine were studied. Unlike 3,5-dimethylpyrazole, more acidic pyrazole, 5-methyl-3-trifluoromethylpyrazole, and 3,5-bis(trifluoromethyl)pyrazoles are deprotonated to give pyrazolate bridges. The structural features of the obtained compounds are discussed based on X-ray diffraction data.

The reaction between Co(Hdmpz)2(OOCPh)2 and cobalt acetate hydrate leads to the deprotonation of coordinated pyrazole and formation of pyrazolate-bridged Co2(μ-dmpz)2(Hdmpz)2(OOCPh)2 binuclear complex. The structure of the complex was determined by X-ray crystallography.

Dissolution of benzoic or pivalic acid in excess triethylamine followed by crystallization was found to yield single crystals of 1: 1 and 1: 2 complexes, respectively. X-ray crystallography have shown that the complex with benzoic acid is an (Et3NH)+(OOCPh)− ion pair, in which the proton is transfered from the acid to the base (N⋯O 2.629(2) A), and the complex with pivalic acid contains, in addition to the ion pair (N⋯O 2.649 A), the homoconjugate anion (ButCOO)(H)(OOCBut)− (O⋯O 2.521 A).

The dissolution of aqueous copper acetate in tetrahydrofuran gives the Cu2(μ-OOCMe)4(thf)2 complex (1), and its reaction with triethylamine in the presence of acetic acid yields “[Cu2(μ-OOCMe)4[μ-OOCMe(HNEt3)]”n polymer (2). Complexes 1 and 2 react with 3,5-dimethylpyrazole to form Cu(Hdmpz)2(OOCMe)2 (3) and Cu2(μ-OOCMe)4(Hdmpz)2 (4), respectively. The structures of complexes 1–4 and that of solvate 4 × 0.5C6H6 (5) are determined by X-ray diffraction.

The placement of 1918 redwing nests has been analyzed, including 214 nests of 90 marked females (2–8 known nests per female). A high level of intraspecific and individual variation in utilization of different types of nest supports is described. It is shown that redwings choose nest sites without regard to previous experience (either positive or negative) or to the placement of their parent nest. Under conditions of the northern taiga, such behavior provides for significant reduction of chick mortality by the end of the season. This is con- firmed by comparison with the song thrush (T. philomelos), which nests mainly on spruce trees.

Carotenoids were found for the first time in the vitreous body of human eye during the fetal period from week 15 until week 28. Their maximum content was timed to week 16–22. No carotenoids were found the vitreous body of 31-week fetuses, as well as adult humans, which corresponds to the published data. It was shown using HPLC that chromatographic characteristics of these carotenoids correspond to those of lutein and zeaxanthin, characteristic pigments of the retinal yellow macula.

The possibility of replacing the electrolyte based on imported ethylene carbonate with a domestic SO2-containing electrolyte based on propylene carbonate was considered for the example of operation of the negative electrode of a lithium-ion battery.