Vol. 47 No. 1 (230) (2013)

Interactions of potassium salt–dimethylsulfoxide (DMSO)–water systems in 25–45°C temperature range were studied using electrical conductivity method. The results show that the conductance of these solutions depends on anions salvation state and is reduced according to this row: NO$^–_–3$>Cl^–>I^–>Br^–. Ion mobility increases with rising of temperature, which leads to an increase in the limiting conductance. With the addition of DMSO appears an extreme point on the dependence, which becomes more harshly when the temperature increases. At DMSO high concentrations (>1.60 M), K⁺–DMSO interaction becomes more intensive, which leads to the formation of bulky solvate shell affecting negatively on the ion mobility. 

New method of synthesizing NH₂/NH₂ capped polyaniline tetramer – 4,4'-di(p-aminoanilino)-diphenylene, by oxidative condensation of 4-aminoacetanilide with N-acetyldiphenylamine and subsequent hydrolysis of the obtained 4,4'-di(p-acetylamino)-N-acetyldiphenylamine is discussed. 

Interaction of monomethylol urea with isotsianuric acid has been investigated at different molar rations. Mono-, di- and tris-substituted derivatives of isotsianuric acid have been obtained. The compounds have been studied by IR, PMR spectroscopy and elemental analysis. 

In present work the study of frequency-dependent effects of extremely low frequency electromagnetic field (ELF–EMF) and mechanical vibration (MV) on specific electrical conductivity (SEC) of distilled water (DW) and physiological solutions (PS) is described. The purpose of this study was to find out the frequency windows and demonstrate the dependency of these physical factors’ effect on the environmental conditions. With this aim frequency-dependent (1–9 Hz) effect of ELF–EMF and MV (1 h) on SEC of DW and PS in light and normal background radiation (NBGR) has been investigated. As the “windows” have been observed only at 4 and 8 Hz the next experiments have been performed at this frequency. The experiments were carried out in the following media: in light ($ E_v=500–550~lux$ ) and NBGR, in dark and NBGR (in wooden box), in dark and low background radiation (in lead box, $R<1\mu R / h$ ) during 10 min.

The melting of DNA–methylene blue (MB) complexes has been carried out at 0.002 M and 0.02 M Na⁺ concentration. The values of melting parameters – melting temperature and melting interval width were obtained in concentration ratio change interval r=[ligand]/[DNA] – 0<r≤0.33. It was revealed that melting interval width change of complexes depending on ligand concentration arises at 0.02 M Na⁺ and r≤0.1 and gets out on plateau at r>0.1, while at 0.002 M Na⁺ this dependence acquires bell-like form. The increase of the interval of melting temperature was revealed at mentioned ionic strengths of solution depending on ligand concentration.

In the current study we investigated the Rana ridibunda tadpole’s liver arginase limited trypsinolysis in order to obtain information about the sensitive bonds towards proteases, as well as about the structural and functional interrelations during metamorphose. After 18 h of limited trypsinolysis in the early stages of tadpole development (21–27) appeared relatively massive fragments, the degradation of fragments deepen concomitant to the real metamorphose approach (28–29 stages). Enzyme pre-incubation with Mn²⁺ leads to stabilization of activity and protects the enzyme from proteolytic inactivation. 

Thermophilic L-aminoacylase Geobacillus stearotermophilus was immobilized on silochrome C-80 with glutaraldehyde. Immobilization process does not affect the temperature optima of derived preparations, but increase in the thermal stability of the immobilized aminoacylase was observed. Michaelis constants ( K_m) were calculated for N-acetyl-L-methionine, N-acetyl-L-valine and N-acetyl-L-alanine. It was shown that as a result of immobilization K_m for N-acetyl-L-methionine increased more than 2-fold. 

It is shown that the amyloid beta peptides Aβ(1-16) and Aβ(1-40) and a cytokine from neurosecretory granules of bovine neurohypophysis, Proline Rich Peptide PRP-4, are truncated at the presence of multifunctional dipeptidyl peptidase IV (CD26/DPPIV), widely expressed in different mammalian tissues. It means that these neuropeptides represent substrates of the enzyme. Besides, it appeared that at the presence of CD26/DPPIV the process of Aβ(1-40) aggregation in vitro was hindered. 

By statistical analysis of study results it has been established that there are not any significant differences between indices of ammonifiers in brown forest soils sprayed and non-sprayed by tested biopesticides. The study indicates that BT-based insecticides, introduced into forest biocenosis, are preserved in brown forest soils during four (BT E-3, BT CM-25) or five (BT AP-8, BT AM-22) months, do not influence adversely on soil-inhabiting ammonifiers of mentioned soils and, therefore, can be widely used in plant protection.

11 new species and 2 new genera belonging to Malvaceae, Onagraceae, Rosaceae, Asteraceae, Liliaceae, Lamiaceae, Boraginaceae, Papaveraceae, Crassulaceae families were found during study of the flora and vegetation of Eastern part of Ijevan floristic region. 

A single cell cytophotometry was used to analyze the amount of RNA and proteins in porcine cells that are susceptible to African Swine Fever Virus (ASFV). The obtained results show that ASFV infection results in depletion of total RNA in the nucleus of monoblasts and monocytes. The level of nuclear acidic proteins in monoblasts is also less, than in control during all time of infection, whereas in monocytes it is higher, than in uninfected cells at the final stage of infection. These data can be used in further researches to elucidate cytopathogenesis of ASFV infection. 

Three-D excitation-emission matrix (EEM) fluorescence spectra of Human Serum Albumin (HSA) were measured at the presence of dimethylsulfoxide (DMSO) at t=25°C during 270 min before and after adding DMSO in different concentrations. It has been shown that DMSO at low concentrations (5%) increase heat-resistance of HSA changing the solvent structure around the protein molecule, it causes conformational changes as well in protein. Drastic changes are observed in the protein struture at DMSO higher concentration (20%). Keywords: human serum albumin, excitation-emission matrix, fluorescence spectroscopy, dimethylsulfoxide, structural changes.

MEFV (Mediterranean Fever) gene is responsible for Familial Mediterranean Fever (FMF). Association of the MEFV gene mutations with clinical conditions other than FMF has recently been a subject of discussion where patients with other inflammatory conditions have also been diagnosed with FMF.