Lipemia modeled by injections of Triton WR-1339 (500 mg/kg) and poloxamer 407 (500 mg/kg) to mice were compared. LP fraction and subfraction compositions were compared by small-angle X-ray scattering on a diffractometer. Both compounds in the same dose caused a sharp increase in serum concentrations of total cholesterol (CH) and triglycerides (TG), the increases in response to poloxamer 407 being more pronounced. The differences in the models consisted in the levels of atherogenic fractions: CH-VLDL (subfractions CH-VLDL 1-2 ) and CH-LDL, which were higher under the effect of poloxamer 407. Similar increases were observed for atherogenic fractions: TG-VLDL (subfractions TG-VLDL 1-2 ) and TG-LDL (subfractions TG-LDL 1-3 ). A specifi c feature of the model induced by poloxamer 407 was elevation of the concentrations of antiatherogenic CH-HDL and TG-HDL (subfractions CH-HDL 2 and TG-HDL 2 ). Both models exhibited high similarity, but changes in atherogenic fractions were more pronounced under the effect of poloxamer 407.

The sizes of semiconductor nanocrystals of CdSe/CdS quantum dots (QDs) synthesized by the colloidal method were estimated using small-angle X-ray scattering. The distribution of QD nanocrystals in organic solvents of different polarities and in polymer gels and matrices is studied. Structural invariants of scattering QD particles (heterogeneities of the electron density)—namely, inertia radii and sizes, forms, and dispersive composition of particles—are determined. The contribution of scattering by QDs in solutions and gels is calculated. The effective sizes of particles and their aggregates are determined, and the parameters of the distribution over the QD sizes in organic solvents and polymer matrices are estimated. The typical distance between particles in samples is determined. The position of the maximum at the beginning of the small-angle scattering curves corresponds to the distance d m = 2π/h 0 between the planes (here, h 0 is the position of the maximum on the scale h). It is 74–76.9 Å for solutions, 60 Å for gels, and 99 Å for polymer matrices with concentrations of up to 0.15% and 77 Å for those with the concentrations exceeding 0.15%, which is close to the estimation of the sizes of separate CdSe QDs that was obtained from the distribution histograms (60–80 Å). This result shows that CdSe/CdS QDs introduced in the polymer matrices disperse to form either separate particles or small aggregates and located at a distance on the order of 80 Å from each other.

A new technical approach to investigation of heterogeneous catalysts with deposited metallic nanoparticles of the active component is suggested. Small-angle X-ray scattering (SAXS) patterns for powder samples of the support matrices with deposited metal particles (Pt, Pd and others) taken at varying density contrast are shown to provide essential information on the structure and dispersity of the active components and their interaction with the support surface, which allows an integral assessment of the formation of strong chemical binding of deposited metal to the support matrix. The measured structural characteristics are compared with data obtained by other physicochemical methods, in particular, transmission electron microscopy (TEM). The suggested technique is verified using mathematical models and applied to a real heterogeneous catalyst Pt/γ-Al2O3. The proposed method of SAXS data analysis makes it possible to reveal the formation of active sites in heterogeneous catalysts and optimize their preparation procedures.

We compared fractional composition of blood serum lipoproteins (LP) in female ICR mice and Wistar rats induced by single administration of a nonionic detergent Triton WR 1339 in doses of 300 and 500 mg/kg. Lipemia in animals of both species was characterized by a sharp increase in the concentration of cholesterol and, particularly, of triglycerides in blood serum lipoproteins by the 24th hour after administration of the detergent. We revealed a significant increase in the concentrations of atherogenic VLDL cholesterol (due to VLDL2), intermediate density lipoproteins, and LDL. These changes were more pronounced in rats. The model of lipemia can be used to study the role of fractional composition of lipoproteins and, particularly, of triglycerides in the pathogenesis of atherosclerosis. Moreover, this model holds much promise for evaluation of the efficiency of hypolipidemic drugs (statins and fibrates) in normalizing the increased level of atherogenic cholesterol of VLDL and LDL.

Using a novel small-angle X-ray scattering (SAXS) method for determination of fractional and subfractional composition of lipoproteins (LPs), a significant elevation of total cholesterol-lipop- roteins (C-LP) and, especially, total triglyceride- lipoproteins (TG-LP), was shown in this work. Among the LP fractions, poloxamer 407 was shown to significantly increase proatherogenic total C-LDL, TG-LDL and, especially, their precursors C-VLDL and TG-VLDL, while only exhibiting a moderate increase in the antiatherogenic C-HDL and TG-HDL fractions. With regard to the VLDL subfractions, significant elevations were observed in both subfractions studied; namely, C-VLDL1-2 and C-VLDL3-5. Similar chang- es were noted in the TG-VLDL1-2 and TG- VLDL3-5 subfractions. The C-IDL and TG-IDL subfractions were increased significantly (?20- to 30- fold), while the C-LDL1-3 subfraction was moderately (?3- to 5-fold) increased at 48 hrs and at day 4. In the moderately elevated (?2- to 4-fold) anti-atherogenic HDL fraction, the C-HDL2 subfraction was increased more significantly (?4- fold) compared to the C-HDL3 subfraction; how- ever, both C-HDL subfractions returned to base- line by day 4. The elevation in the TG-HDL2 subfraction was observed only at 24 hrs. Mouse models of hyperlipidemia and atherosclerosis are useful to evaluate the role of “individual” LPs, as well as their fractions and subfractions, in hyperlipidemia and the genesis of atherosclerosis.

Objective. To characterize specters of common and modified lipoproteins (LP) in serum of pts with rheumatoid arthritis (RA) according to age and sex and compare with healthy donors (with normal lipid level). Material and methods. 103 pts with RA (88 female and 15 male) aged 21 to 69 years were included. Specters of common and modified LP in serum and plasma were evaluated with small-angle x-ray scattering. Results. Low level of intermediate density lipoproteins (IDLP) subfractions and very low density lipoproteins (VLDLP) as well as high level of low density lipoproteins (LDLP)30 was revealed in pts with RA. Mean level of LP modification was about 60%. High density lipoproteins (HDLP) subfraction was least and IDLP subfraction – most susceptible to modification. LP modification level increased due to LDLP and VLDLP fractions. This level had a tendency to increase with age because of elevation of atherogenic LP part. Mean values of common LP did not differ between sex and age groups of pts with RA. Unexpectedly low (in comparison with normal lipid content) level of LP modification of the whole fraction of HDLP was the feature of modified LP specter in pts with RA. Conclusion. Level of common and modified LP in blood plasma and serum of RA pts is connected with general state of lipid metabolism and immune defense factors balance. Low level of VLDLP cholesterol and high level of LDLP cholesterol as well as high degree of LP of these fractions modification may be probably considered as markers of RA activity.

Lactoferrin (LF) is a Fe3+-transferring glycoprotein and is contained in human barrier fluids, blood, and milk. LF is an acute phase protein, is involved in nonspecific defense, and displays a unique set of biological functions. Small-angle X-ray scattering and light scattering experiments demonstrated that DNA and oligosaccharides added to LF with various levels of initial oligomerization increased the oligomerization rate. Almost complete dissociation into monomers was observed when 1 M NaCl was added to LF oligomers obtained in the presence of DNA, oligosaccharides, and nucleotides, previously identified as oligomerization effectors. LF complexes obtained with different oligomerization effectors differed in stability. Incubation with 50 mM MgCl2 completely destructed LF complexes formed in the presence of ATP and oligosaccharides but only partly destructed AMP- and d(pT)(10)-dependent complexes, which was followed by the formation of new complexes with a higher salt stability. A possible role of oligomerization in various LF functions is discussed.

Objective. To characterize specters of common and modified lipoproteins (LP) in serum of pts with rheumatoid arthritis (RA) according to age and sex and compare with healthy donors (with normal lipid level). Material and methods. 103 pts with RA (88 female and 15 male) aged 21 to 69 years were included. Specters of common and modified LP in serum and plasma were evaluated with small-angle x-ray scattering. Results. Low level of intermediate density lipoproteins (IDLP) subfractions and very low density lipoproteins (VLDLP) as well as high level of low density lipoproteins (LDLP)30 was revealed in pts with RA. Mean level of LP modification was about 60%. High density lipoproteins (HDLP) subfraction was least and IDLP subfraction – most susceptible to modification. LP modification level increased due to LDLP and VLDLP fractions. This level had a tendency to increase with age because of elevation of atherogenic LP part. Mean values of common LP did not differ between sex and age groups of pts with RA. Unexpectedly low (in comparison with normal lipid content) level of LP modification of the whole fraction of HDLP was the feature of modified LP specter in pts with RA. Conclusion. Level of common and modified LP in blood plasma and serum of RA pts is connected with general state of lipid metabolism and immune defense factors balance. Low level of VLDLP cholesterol and high level of LDLP cholesterol as well as high degree of LP of these fractions modification may be probably considered as markers of RA activity.

The effect of the sintering temperature on the structural characteristics of nanosized zirconium dioxide particles treated by microwave radiation during the drying process was investigated by small-angle X-ray scattering and the BET method. It was shown that the specific surface area, particle size, polydispersivity index, and surface and mass fractal dimensionality of zirconium dioxide depend on its heat treatment conditions.

Lactoferrin (LF) is a multifunctional acute-phase protein involved in nonspecific defense against bacteria, viruses, and cancer diseases and is present in human barrier fluids, blood, and milk. Small-angle X-ray scattering (SAXS) and light scattering (LS) demonstrated for the first time that LF occurs in the form of oligomers, with a high monomer unit number in the solution. The degree of LF oligomerization depends on the LF concentration and the storage period of non-frozen neutral LF solutions. The average inertial radius of scattering particles (Rg) reaches 100–450 Å at LF concentrations comparable with those in human milk, while Rg of LF monomers is 26.7 Å. LF forms complexes with various nucleotides and hydrolyzes them. The addition of ATP or AMP to LF solutions accelerates LF oligomerization and increases Rg to 600–700 Å, regardless of the initial degree of LF oligomerization. According to the different models (sphere, plate, and cylinder) of LF aggregates, its complexes with such Rg presumably contain several tens to thousands of LF monomers. The possible role of oligomeric complexes in multiple biological functions of LF is discussed.

It is shown that in thermoneutral conditions ISIAH (Inherited Stress-Induced Arterial Hypertension) hypertensive rats had a lower level of high-density lipoproteins (HDLP) in plasma and a higher atherogenic coefficient compared to normotensive Wistar rats. After cooling there were different changes in fractional composition of plasma lipoproteins both in normo- and hypertensive rats. These changes depended on the cooling rate and were more pronounced after slow cooling. Slow cooling resulted in a more significant increase of plasma HDLP and in a greater decrease in LDLP and atherogenic coefficient in hypertensive rats compared to normotensive ones.

Using a novel approach, we have analyzed 30 parameters characterizing detailed spectrum and fractional content of LPs in plasma of patients with tick-borne encephalitis (TBE). The blood plasma of all TBE patients (30 patients), as compared with that of healthy individuals (120 patients), is characterized by decreased concentrations of many LP subfractions and of the total concentration of all plasma LPs (hypolipoproteinemia). The observed difference in some parameters was statistically significant. Using computer-assisted factor analysis, we have shown that according to these 30 parameters TBE patients are similar to patients with multiple sclerosis and systemic lupus erythematosus. The results provide grounds for using data on blood plasma LPs as additional criteria for diagnosis of TBE.

Molecular interactions of RNA cleaving compounds - conjugates of 1,4-diazabicyclo[2.2.2.]-octane substituted at the bridge position with tetradecamethylene fragment AA and imidazole were investigated using light scattering and small angle x-ray scattering methods. The compounds are known to efficiently cleave RNA and one source of the activity could result from micellar catalysis. It was found that the compounds indeed are capable of forming complex aggregates in solution. However, maximal efficacy of RNA cleavage by the conjugates is observed at concentrations well below the concentration required for micelle formation.

As a result of large-scale nuclear tests on the Novaya Zemlya test site (1955-62) the Tundra Nentsy population of Yamal-Nentsy autonomous region (YNAR) fell under the constant influence of incorporated radioactive isotopes (137Cs and 90Sr). Therefore, it is very important to analyze a possible spectrum of diseases of Tundra Nentsy population.

In thermoneutral conditions, inherited stress-induced arterial hypertensive (ISIAH) rats had a lower level of high-density lipoproteins (HDL) in plasma and a higher value of the atherogenic coefficient in comparison with normotensive Wistar rats. Five days after cooling, there were different changes in the fractional composition of plasma lipoproteins in normo- and hypertensive rats. These changes depended on the cooling rate and were more expressed after slow cooling. Slow cooling caused a more significant increase in plasma HDL and a marked decrease in low-density lipoproteins (LDL) in hypertensives compared to normotensives. These changes resulted in normalization of plasma HDL and a decrease in the atherogenic coefficient value in hypertensive rats.