The transformation of separate crystals of CaS04·2H20 (DH) into CaS04·0.5H20 (HR) in an aqueaus solution of H3P04 and H2S04 at 90-97°C was studied using a JSM-35CF SEM. The source DR and acids were reagent or eommereial (taken from the produetion of H3P04 by a wet process). DR was allowed to eonvert into HR and periodie samples of the suspension were drawn, filtered, and investigated in the solid phase by SEM. It was shown that the dehydration of reagent DH speeimens oeeurred through the reerystallization mechanism, whereas the transformation of eommereial DR into HH was basieally topoehemieal and developed by a relay race meehanism without any phase transformation front. The observed differenee between eommereial and reagent DR speeimens may be explained by differenees in their erystalline strueture, initial partiele size and by the presenee of impurities in DH and aeids. It is established that ehemieal impurities ean ehange the meehanism of the phase transformation of the erystals DH into HH.

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The possibilities of using electrical and viscoelastic parameters of erythrocytes in patients with colorectal cancer (CRC) of different stages were demonstrated using optical cell detection system based on the dielectrophoresis method. The deformation amplitude, portion of deformed cells, generalized viscosity, rigidity, equilibrium frequency position, and electrical conductivity were the most significant parameters for determining patients with CRC, as well as early and late stages, included in the created model of a riskometer for the disease diagnosis. The created diagnostic “panels” with a high diagnostic accuracy, sensitivity, and specificity allowed to one determine patients with CRC (specificity 0.91, sensitivity 0.96), as well as early and late stages of the disease (specificity 0.64, sensitivity 0.86).

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Hemorheological disorders in structural and functional parameters of erythrocytes are involved in the pathological process in type 2 diabetes mellitus (DM). Aim: to investigate the feasibility of differential diagnosis of the degrees of rheological disturbances in patients with type 2 DM by dielectrophoresis of erythrocytes. Methods: 62 subjects (58.7 ± 1.6 years) with type 2 DM diagnosed according to the criteria of the ADA were subdivided into two groups: medium (n = 47) and high (n = 15) risk of microcirculatory disturbances (EASD, 2013). Electric and viscoelastic parameters of erythrocytes were determined by dielectrophoresis using an electric optical system of cell detection. Results: the progression of rheological disturbances in the patients with type 2 DM was accompanied by significant decreases in deformation amplitude; dipole moment; polarizability; and membrane capacity; and increases in conductivity, viscosity, rigidity, hemolysis, and formation of aggregates (p < 0.05). Combined use of the parameters increased sensitivity (97.8%) and specificity (86.7%) for diagnosis of rheological disturbances in type 2 DM. Conclusion: the proposed experimental approach possesses low invasiveness, high productivity, shorter duration, vividness of the results. The method allows to evaluate not only local (renal and ocular) but also systemic status of microcirculation using more than 20 parameters of erythrocytes.

Possible early diagnostic application of optical methods (dielectrophoresis, spectral and imaging ellipsometry, Fourier-transform infrared spectroscopy, Raman spectroscopy) in studies of red blood cells and serum of patients with diffuse liver disease with varying degrees of fibrosis has been evaluated. Application of combined optical methods was confirmed to significantly improve the performance of sensitivity, specificity, and accuracy index as well as to achieve the reliable results in diagnosis of both severe fibrosis and slight ulterior liver fibrosis. Identified diagnostic potential of optical methods can be effectively utilized in noninvasive screening evaluation of stages of diffuse liver disease of various geneses.

67 patients (mean age 48 ± 1 year) with diffuse liver diseases of various origins were examined. It has been established that an increase in the degree of fibrosis is associated with an increase in the resonance intensity of glucose-6-phosphates, adenosine monophosphate (AMP), inosine monophosphate (IMP), pyrophosphates, 2,3-DPH and a decrease in the resonances of inorganic phosphates and phosphocreatine, γ-, alpha- and beta- ATP, -UTP, Hb- and Mg-ATP, as well as beta- and alpha-ADP. The predictive value of a positive result of erythrocyte 31P NMR spectroscopy for liver fibrosis is 92.3% (sensitivity 85.71%, specificity 80%). In the IR spectra of the blood serum of patients with severe fibrosis, in contrast to moderate fibrosis, the resonance intensity is higher at 1280, 3190 and significantly lower at 776, 818, 889, 966, 1399.1450, 1570, 1635 cm-1, which indicates the presence of protein molecules with a secondary structure mainly in the form of a helix (alpha-helix) compared with the structure in the form of a folded sheet (beta-sheet) (p <0.001-0.05). The combined use of 31P NMR spectroscopy of erythrocyte suspensions and IR spectroscopy of blood serum made it possible to increase diagnostic accuracy (96%), sensitivity (97%) and specificity (91%) in distinguishing between degrees of liver fibrosis in contrast to the isolated use of these methods.

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