Hydroxyapatite-biopolymers-ZnO composite with sustained Ceftriaxone release as a drainage system for treatment of purulent cavities.

Composite based on nano-sized hydroxyapatite (HA), zinc oxide (ZnO), chitosan (CS), alginate (Alg) with the function of sustained Ceftriaxone (CF) release was created as molecular sorption-aspiration drainage system (SADS), designed for the treatment of purulent cavities of various genesis, including peritonitis. ZnO stabilizes the composite structurally, reducing the swelling by 1.5 and porosity by 1.

Single-walled carbon nanotubes loaded hydroxyapatite-alginate beads with enhanced mechanical properties and sustained drug release ability.

Single-walled carbon nanotubes (SWCNTs) containing biomaterial with enhanced mechanical properties for the potential orthopedic application were synthesized and investigated. X-ray diffraction and X-ray fluorescence analysis were indications of the formation of calcium-deficient (Ca/P = 1.65) hydroxyapatite (HA) with a small carbonate content under influence of microwave irradiation.

Synthesis, characterization, in vitro biocompatibility and antibacterial properties study of nanocomposite materials based on hydroxyapatite-biphasic ZnO micro- and nanoparticles embedded in Alginate matrix.

The paper presents the results of studies of biocompatibility and antibacterial properties of multiphase nanocomposite materials based on HA-Alg-ZnO (hydroxyapatite‑sodium alginate-biphasic zinc oxide) and HA-ZnO (hydroxyapatite‑zinc oxide), which were synthesized from the analytically pure calcium nitrate tetrahydrate, ammonium hydrophosphate, hydrous ammonia, zinc nitrate hexahydrate and calcium chloride. The samples' antimicrobial activity assessment was carried out on Gram-negative (E. coli, P.

C fullerene loaded hydroxyapatite-chitosan beads as a promising system for prolonged drug release.

Bioactive composite material in the form of beads, based on natural polysaccharide Chitosan (CS), hydroxyapatite (HA), and C fullerene (C), was synthesized under influence of microwave irradiation (MW). The bead is a 3D matrix consisting of CS macromolecules cross-linked with sodium tripolyphosphate with HA and C particles immobilized in its structure. XRD and FTIR data confirmed the formation of calcium deficient carbonate substituted HA with needle-shaped nanocrystallites of about 80 nm.

C fullerene and its nanocomplexes with anticancer drugs modulate circulating phagocyte functions and dramatically increase ROS generation in transformed monocytes.

Background: C fullerene-based nanoformulations are proposed to have a direct toxic effect on tumor cells. Previous investigations demonstrated that C fullerene used alone or being conjugated with chemotherapeutic agents possesses a potent anticancer activity. The main aim of this study was to investigate the effect of C fullerene and its nanocomplexes with anticancer drugs on human phagocyte metabolic profile in vitro.

Composite material based on hydroxyapatite and multi-walled carbon nanotubes filled by iron: Preparation, properties and drug release ability.

The novel bioactive composite material based on hydroxyapatite and multi-walled carbon nanotubes filled by iron was synthesized by the "wet chemistry" method and characterized in detail by various experimental techniques including the X-ray diffraction, Fourier transform infrared and energy-dispersive X-ray fluorescence spectroscopy, thermogravimetric and differential thermal analysis. The swelling behaviour was quantified by measuring the changes in sample weight as a function of sample immersion time in a phosphate buffered saline (PBS). Bioactivity test was carried out by soaking the samples in PBS.

Structural features of hydroxyapatite and carbonated apatite formed under the influence of ultrasound and microwave radiation and their effect on the bioactivity of the nanomaterials.

The samples of hydroxyapatite and carbonate substituted hydroxyapatite (CHA) were obtained under the influence of physical factors, namely ultrasound (US) and microwave (MW) radiations. The results of Fourier transform infrared spectroscopy and X-ray diffraction analysis have proved the formation of the calcium deficient hydroxyapatite and B-type CHA with the Ca/P ratio in the ranges 1.62-1.

Controllability of brushite structural parameters using an applied magnetic field.

The paper studies the influence of low intensity static magnetic field on brushite structural and microstructural parameters using the X-ray diffraction and the transmission electron microscopy. This effect was shown to have various influences on DCPD (Dicalcium Phosphate Dihydrate) structure depending on a magnetic field configuration or time of synthesis, which allows achieving controllability of the main properties of an obtained material. The influence of the magnetic field leads mostly to the decrease of crystallite sizes with no impact on the crystal lattice parameters.

[Interaction of DNA nucleotide bases with anticancer drug ThioTEPA: molecular docking and quantum-mechanical analysis].

Using modern methods of molecular docking, quantum chemistry and quantum theory of atoms in molecules the interaction of anticancer drug ThioTEPA with isolated nucleotide bases and deoxyribonucleosidemonophosphates of DNA has been studied. Physical properties and some trends of binding have been established for the complexes of "nucleotide base + ThioTEPA" and "deoxyribonucleosidemonophosphate + ThioTEPA" types. It has been shown that strong hydrogen bonds of NH.

Silver-doped hydroxyapatite coatings formed on Ti-6Al-4V substrates and their characterization.

Coatings with antibacterial components for medical implants are recommended to reduce the risk of bacterial infections. Therefore hydroxyapatite (HA) coatings with addition of chitosan (CS) and silver (Ag) are proposed in this work in an attempt to resolve this problem. Ti-6Al-4V substrates were modified by a chitosan film to study the influence of surface modification on the formation of the HA-Ag and HA-CS-Ag coatings.

Characterization and in vivo evaluation of chitosan-hydroxyapatite bone scaffolds made by one step coprecipitation method.

Chitosan/hydroxyapatite scaffolds could be used for bone regeneration in case the application of auto- or allografts is impossible. The objective of the present work was to characterize and study in vivo biodegradation of simple chitosan/hydroxyapatite scaffolds. For this purpose, a series of chitosan/hydroxyapatite composites has been synthesized in aqueous medium from chitosan solution and soluble precursor salts by a one step coprecipitation method.

252Cf plasma desorption mass spectrometric study of interactions of steroid glycosides with amino acids.

252Cf Plasma desorption with time-of-flight mass spectrometry (TOF-PDMS) has been applied to comparative studies of the interactions of steroid glycosides (SGs) of the spirostan series with amino acids. SGs can interact with amino acids to form heteroclusters of the type [SG + aminoacid + H](+) and [SG + aminoacid + K](+). It is shown how the affinity of SGs for amino acids depends on the structures of both the SG carbohydrate chain and the SG aglycone, and on the nature of the amino acid side chain.

[Measurement of trace elements in blood serum by atomic absorption spectroscopy with electrothermal atomization].

Describes a method for measuring trace elements Cr, Mn, Co, Fe, Cu, Zn, and Mo in the blood serum using non-flame atomization (KAC 120.1 complex). Optimal conditions for preparing the samples were defined, temperature regimens for analysis of each element selected, and original software permitting automated assays created.

[Mass spectrometric and quantum chemical study of dimeric associates of nucleosides].

Deoxyribonucleosides H-bonded pairs were investigated using fast atom bombardment mass spectrometry and MNDO/H quantum chemistry method. It was shown that "rare" (enol or imin) forms of the nitrogen bases could form pairs with energy comparable with "canonical" base pair energy. It was shown that pair stability rows, which are measured using different experimental techniques, were in conformity each with other.

[Use of time-of-flight mass spectrometry with ionization division fragments of californium-252 for studying the mechanisms of action of drugs on DNA and its components].

Using soft-ionization mass spectrometry (252-Cf particle desorption mass spectrometry, PDMS) a minor adduct of anticancer drug prospidine and deoxyguanosine-5-phosphate (pdG) has been found. It has been shown experimentally that PDMS is very useful for study of biological mixtures as well as mechanisms of interactions between drugs and biomolecules.

Study of anticancer drug interaction with DNA by means of particle-induced desorption mass spectrometry: prospydine and deoxyguanosine-5'-monophosphate.

Using 252CF particle desorption mass spectrometry, the interaction between an antitumour drug prospydine (Pro) and deoxyguanosine-5'-monophosphate (pdG) has been studied. The adduct which corresponds to a peak at m/z 524.5 and which occurs as a result of the particular degradation of Pro during its alkylating of pdG has been found.

[Study of the interaction of triethylenethiophosphamide with nucleotides by mass spectrometry with ionization by fission fragments of californium-252].

Study of interaction of the antitumor alkylating drug triethylenethiophosphoramide (thioTEPA) with nucleotides (dGMP and dCMP) suggests highly perspective employment of 252-Cf fission fragment induced desorption mass spectrometry (252-Cf PDMS) in biochemical pharmacology. Using the 252-Cf PDMS the molecular masses of the unstable, unvolatile, high-molecular substances of biological origin and the chemical adducts or complexes with drugs can be used to establish some structural-functional parameters of the above mentioned biomolecules and their derivatives in microvolumes of the incubation medium. The resulting data may be used for modelling chemotherapeutic processes of "drug-biomolecule-target" type.

Direct observation of the alkylation products of deoxyguanosine and DNA by fast atom bombardment mass spectrometry.

By the methods of fast atom bombardment (FAB) mass spectrometry, thin-layer chromatography and ultraviolet absorption spectroscopy adducts have been studied which are formed by an antitumour alkylating drug thiotepa both in a model system, containing only deoxyguanosine (dGuo), and in DNA. Analysis of the model reaction mixture (dGuo + thiotepa) by FAB mass spectrometry permitted observation of adducts dGuo thiotepa, 2dGuo thiotepa, and also the products of their further modification in solution, which occurs by hydrolysis of the glycosidic bond and also by opening of the imidazole ring. In the case of DNA FAB mass spectrometry made it possible to characterize adducts of thiotepa with guanosine (Gua) and adenosine (Ade) without their preliminary purification.

Experimental and theoretical study of energetics of complex formation between nucleic acid bases and the bases with amide group.

A number of nucleic acid base pairs and complexes between the bases and the amide group of acrylamide have been studied experimentally by using mass spectrometry and theoretically by the method of atom-atom potential function calculations. It has been found from temperature dependencies of peak intensities in mass spectra of m2.2.

Associate hydrations and energies of nucleotide bases as revealed by low-temperature field ionization mass-spectrometric data.

The formation of water clusters, polyhydrates of nucleotide bases and their associates during simultaneous condensation of water and base molecules in vacuo onto a surface of a needle emitter cooled to 170 K was studied by field ionization mass spectrometry. It was found that different emitter temperatures are characterized by a specific distribution of intensities of cluster currents, depending on the number of water molecules in clusters. These distributions correlate with structural peculiarities and the relative energetics of formation of water clusters, polyhydrates of nucleotide bases and their associates at low temperature.

[Ultraviolet irradiation of blood in patients with pulmonary tuberculosis].

The described methods for ultraviolet blood radiation were used in 80 patients: 51 had tuberculosis of the bronchopulmonary system and 29 nonspecific pulmonary diseases. A marked clinical effect was confirmed by subjective and objective methods. In all cases blood pressure moderately decreased, there was a tendency to hypercoagulation decline, the erythrocyte count and hemoglobin level increased.