Cyclic Methacrylate Tetrahydropyrimidinones: Synthesis, Properties, (Co)Polymerization.

During radical polymerization of novel biocidal methacrylate guanidine monomers, a cyclic byproduct was discovered and identified as 2-imino-5-methyltetrahydropyrimidin-4(1H)-one (THP). Its methacrylate salt (MTHP) was synthesized and characterized via H and C NMR and pyrolysis chromatography. Synthesis conditions of both THP and MTHP were optimized to high yields, and both MTHP homopolymerization (in aqua) and copolymerization with diallyldimethylammonium chloride (in aqua in salt form) were successfully carried out with middle to high yields, providing a promising platform for potential tailored biocide polymers.

[The role of endoscopic methods in treatment of tracheal cicatricial stenoses].

Treatment of tracheal cicatricial stenosis is one of the most difficult problems of modem medicine. There are two main therapeutic approaches--endoscopic (bronchoscopic) and surgical (open). The paper describes the methods of endoscopic treatment of stenoses allowing achieving complete recovery of tracheal lumen in some cases.

Symmetric C-C stretching mode splitting versus CH2-chain conformation order in sodium montmorillonite modified by cetyltrimethylammonium bromide.

Exploiting Raman spectroscopy and computational modeling, for the first time, we report and explain an interesting phenomenon in clay modified by cetyltrimethylammonium bromide. A splitting of the CH(2)-chain's symmetric C-C stretching Raman mode found at ~1128 cm(-1) in cetyltrimethylammonium bromide into two bands at 1128 and 1139 cm(-1) in clay modified by cetyltrimethylammonium bromide is observed. We demonstrate that this splitting appears if two types of trans-segments with nonequivalent lengths and terminal groups coexist in the CH(2)-chain of the alkylammonium ion embedded into the clay interlayer space.

[Composite biodegradable materials based on polyhydroxyalkanoate].

Conditions for the processing and mixing of biodegradable polymers at temperatures less than their thermal destruction (130-150 degrees C) using standard equipment have been identified. The structure of the polyhydroxybutyrate/valerate (PHB/V) copolymer has been revealed and peculiarities of the crystal phase formation at different monomer ratios have been investigated. It was shown that pure PHB with molecular mass 180-270 kDa has elastic module approximately 1.

[Photodynamic therapy in treatment of lung cancer].

The effectiveness of photodynamic therapy was studied in 20 patients with different stages of lung cancer. We used the photosensitizer--PHOTOHEM and gold vapor laser (Auran). Photodynamic therapy was combined with high-energy laser photodestruction of tumors in 7 patients.