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Tumor development is the consequence of expanding the population of low differentiated cells with unlimited self-maintenance potential, i.e. cancer stem cells (CSCs). Application of new forms of nanocomposites capable of binding to CSCs and inducing the tumor destruction is perspective direction for treating this pathology. There have been developed the methods of obtaining hybrid nanocomplexes containing rare-earth orthovanadates GdYVO4:Eu³⁺, cholesterol and luminescent dye Dil. By immune fluorescence method using monoclonal antibodies to CD44, CD24, CD117 and Sca-1 markers there has been established the change in the ratio of tumor progenitors of various differentiation levels in a general pool of Ehrlich carcinoma (EC) after treatment with hybrid nanocomplexes. Essential reduction in the concentration of the most tumorogenic CD44high cells with simultaneous rise in the number of CD117⁺-cells resulted in an increased index of CD44high/CD117⁺ ratio. It has been demonstrated that application of hybrid nanocomplexes suppressed the tumor growth almost by 80%. The value of cooperative interactions of the cells with different phenotype signs in tumor sites has been proved. The index of CD44high/CD117⁺ ratio can be used as one of diagnostic and prognostic parameters of development and inactivation rate of tumor process when using different types of anti-tumor therapy.

In this work the integral components of the cytoplasmic membrane, lecithin and cholesterol were used for mass spectrometry analysis carried out on polyhexamethyleneguanidine (PHMG) mixtures with lipids. The study was performed by mass-spectrometry methods of the MALDI-TOF MS. Our results showed that despite the common use of PHGM polymer derivatives as disinfectants the persistent intermolecular complexes of PHMG oligomers with lipids were not formed. The binding of polycation PHMG with the membrane has been explained by the model proposed. According to this model PHGM can adhere to negatively charged plasma membrane of bacterial cell due to electrostatic interaction and the formation of loop-like structures. Similar stereochemistry mechanism makes the adsorption of the investigated polycation to membrane robust. The mechanism described together with additional destructive factors provides a reasonable explanation for the PHMG induced damage of bacterial cell plasma membrane and the biocide action of disinfectants prepared on the basis of the PHMG salts.

Changes of lipid components ratio in the rat bile after bombesin neuropeptide infusion (1 microg per 100 g of body weight) were studied in the acute experiment using the thin-layer chromatography. The cholates-to-cholesterol, phospholipids-to-cholesterol, cholesterol-to its esters ratios and also the potent cholesterol crystallization index were calculated and analyzed. Obtained data indicate that bombesin takes influence on the colloidal parameters of bile enhancing the secretion of phospholipids, cholesterol and its esters and free fatty acids. The peptide also intensifies cholesterol etherification and improves the colloidal stability of bile. After bombesin application the potential ability of cholesterol to crystallization remains at normal rate indicating that the useful balance of micelle forming elements is unaffected, that prevents from the development of gallstone disease.

The effect N-stearoilethanolamines on lipide classes and their fatty acid composition was studied in the isolated rat heart under ischemia--reperfusion. It was shown that the amount of cholesterol esters increased at ischemia--reperfusion by 4.6 fold. The addition of 10(-7) M, 10(-6) M and 10(-5) M of N-stearoilethanolamines into perfused solution prevented these negative consequences of the myocardium ischemic injury. The addition of N-stearoilethanolamines decreased the quantity oleinic (18:1 omega 9) and free n-6 fatty acids. N-stearoilethanolamine lowered the amount of short chain saturated fatty acids and also polyunsaturated n-6 fatty acids in cholesterol esters. As well the lipide composition of perfused solutions was also investigated.