Analysis of the Effects Produced by Trade Liberalization in the Republic of Uzbekistan and the EAEU.

This study quantitatively assesses the consequences arising from the liberalization of the regional market in the EAEU member states for the exports of the Republic of Uzbekistan using a number of trade indicators, including Balassa index of revealed comparative advantage, the regional orientation index and others. It is shown that for a significant part of the exports of the Republic of Uzbekistan, the reduction in trade barriers (in particular, nontariff measures of customs regulation) will have a positive effect, i.e., it will contribute to the growth of exports to the Member States of the Union. It is also demonstrated that the main part of the export from the Republic of Uzbekistan does not compete with the export of the EAEU member states in the markets of third countries.

Specific Antibodies to the Fragments of Meningococcal IgA1 Protease during the Formation of Immunity to Bacterial Infections.

The features of individual fragments of IgA1 protease of Neisseria meningitidis serogroup B during the formation of immunity to bacterial infections in animals and humans were studied. The antibodies to the immunogenic regions of the studied proteins are also detected in mice infected with some bacterial pathogens and in humans with bacterial meningitis. A region of IgA1 protease was identified that is not capable of producing antibodies during immunization of animals, but that detects homologous antibodies in the blood of humans and animals recovered from bacterial infections. It has been suggested that this fragment plays a regulatory role in the process of immunogenesis.

Peculiarities of the Formation of Antimeningococcus Immunity in Mice Immunized with Fragments of N. meningitidis IgA1 Protease.

We studied immunogenicity of two recombinant proteins FR.9 and FR.11-3 created on the basis of fragments of the primary structure of N. meningitidis IgA1 protease with different molecular weights containing different sets of T and B epitopes. The proteins actively protect animals infected with live virulent culture of meningococci, serogroups A, B, and C. Analysis of CD4+, CD8+, and CD19+ lymphocyte populations in mouse blood showed predominant contribution of different cell populations to the formation of immune response to different proteins. Injection of FR.11-3 protein to animals did no affect the immunoregulatory index, hence, this protein can be used for creation of immunologically safe vaccine preparation.

Serological Analysis of Immunogenic Properties of Recombinant Meningococcus IgA1 Protease-Based Proteins.

Using the genome sequence of IgA1 protease of N. meningitidis of serogroup B, four recombinant proteins of different structure and molecular weight were constructed. These proteins were equal in inducing the formation of specific antibodies to IgA1 protease and had protective properties against meningococci. In the sera of immunized mice, anti-IgA1 protease antibodies were detected by whole-cell ELISA, which indicated the presence of IgA1 protease on the surface of these bacteria. We hypothesized that the protective properties of IgA1 protease-based antigens and IgA1 protease analogs could be realized not only via impairment of bacterium adhesion to the mucosa, but also via suppression of this pathogen in the organism. The presented findings seem promising for using these proteins as the basis for anti-meningococcus vaccine.

Truncated Variants of Serratia proteamaculans Oligopeptidase B Having Different Activities.

Treatment of native psychrophilic oligopeptidase B from Serratia proteamaculans (PSP, 78 kDa) with chymotrypsin (soluble or immobilized on modified porous glass MPG-PA) in the presence of 50% glycerol leads to production of a truncated enzyme form (PSP-Chtr, ~66 kDa), which retains activity toward the low molecular weight substrate of PSP, BAPNA, but in contrast to PSP, is active toward the protein substrate azocasein. It has been shown by MALDI-TOF mass-spectrometry that PSP-Chtr lacks the N-terminal region of the molecule that envelops the catalytic domain of PSP and supposedly prevents hydrolysis of high molecular weight substrates. It has also been established that the lacking fragment corresponds to the N-terminal highest rank element of the informational structure of PSP. This finding confirms the usefulness of the method of informational structure analysis for protein engineering of enzymes. A similar treatment of PSP with immobilized trypsin also led to production of a stable truncated enzyme form (PSP-Tr, ~75 kDa) which lacked 22 C-terminal amino acid residues and completely lost enzymatic activity, presumably because of changes in the nearest environment of His652 of the catalytic triad.

[Protective properties of recombinant IgA1 protease from meningococcus].

The study of enzymatic and protective properties of recombinant IgA1 protease in active and mutant form showed that active form of IgA1 protease exhibited species - and type-specificity for mouse and human immunoglobulins. Mutant form, which did not exhibit enzymatic activity, had protective properties against meningococcal infection, induced by meningococcus serogroup A, B and C protecting the mice from lethal infection by living virulent culture of heterologous serogroups of meningococcus. Obtained results make it possible to consider IgA1 protease as a perspective preparation at the stages of development of polyvalent vaccine for protection the people from meningococcal infection of various etiology.

Structural features of the interfaces in enzyme-inhibitor complexes.

Specific protein-protein interaction is essential for the function of life systems. A variety of computational methods are being extensively used now-a-days to investigate this interaction and to identify structural features of binding sites. In this paper, the informational structure analysis method was applied to the study of protein-protein interaction interfaces in enzyme-inhibitor complexes. The analysis of amino acid sequence by informational structure analysis method reveals three types of sites (ADD+, NORMAL and ADD-) which differ in the density of first rank elements in the informational structure. ADD+, NORMAL and ADD- sites also differ in their ability towards adaptive conformational reorganization which contributes to the formation of protein-protein interaction interfaces in enzyme-inhibitor complexes. The study of hydrolytic enzymes in complex with their protein inhibitors shows that at least one of the interaction interface sites is of ADD- type. ADD- sites possess an increased ability towards adaptive conformational changes thus enabling effective protein interaction.

Application of DNA condensation for removal of mercury ions from aqueous solutions.

DNA has a unique character that allows it to combine with various chemical substrates at the molecular level, and the DNA binding with chemical pollutants can cause serious damage to the organism. The purpose of this research was to apply the strong bonding character of DNA for the removal of mercury ions. In this research, we used DNA condensation promoted by the action of DNA condensing agents, such as cetyltrimethylammonium bromide and a commercially available combination flocculant made of zeolite, to precipitate out the DNA bound with mercury ion in an aqueous solution. When solutions of mercury at 0.02-100 ppm (parts per million) concentrations at a pH range of 2-11 were treated with double-stranded DNA followed by the condensing agent, more than 95% of the mercury ions could be removed after simple filtration or sedimentation.

[Development of a rapid method for the detection of prostate-specific antigen by immunochromatography].

A single-step qualitative rapid test for the determination of prostate-specific antigen (PSA) in samples of human blood serum by immunochromatography using a complex of colloidal gold with monoclonal antibodies to PSA as the detection agent was developed. The determination limit for PSA in serum blood samples is 10 ng/ml; the analysis time, 15-25 min; the sensitivity of the method, 100%; and its specificity, 92.5%.

[Modified method for determining circulating immune complexes in the complement fixation test with polyethylene glycol precipitate].

The authors have modified a method for determining circulating immune complexes in the complement fixation test. It is shown that with the 7% concentration of polyethylene glycol (PEG)-6000, there is a more complete precipitation of low- and medium-molecular weight immune complexes. The time and temperature of serum incubation were optimized when PEG-6000 was obtained. The use of the soluble circulating immune complexes (sCIC) prepared from human serum as a standard for the construction of a standard plot could substantially enhance the sensitivity of the method (0.325 microg/ ml). The content of circulating immune complexes was studied in donors and in patients with connective tissue dysplasia (CTD) by the improved procedure. In the group of donors, the mean level of sCIC was 0.62 +/- 0.24 mg/ml. In the CTD group, that was 2.32 +/- 0.93 mg/ml; the serum concentrations of sCIC ranging from 1.1 to 5.0 mg/ml. In the donors and patients, the detection rate of serum sCIC was 100%. The proposed method may be clinically used to measure the human serum levels of sCIC.

Development and validation of reversed phase high performance liquid chromatography method for determination of dexpanthenol in pharmaceutical formulations.

This paper describes the validation of an isocratic HPLC method for the assay of dexpanthenol in aerosol and gel. The method employs the Vydac Proteins C4 column with a mobile phase of aqueous solution of trifluoroacetic acid and UV detection at 206 nm. A linear response (r>0.9999) was observed in the range of 13.0-130 microg mL(-1). The method shows good recoveries and intra and inter-day relative standard deviations were less than 1.0%. Validation parameters as specificity, accuracy and robustness were also determined. The method can be used for dexpanthenol assay of panthenol aerosol and gel with dexpanthenol as the method separates dexpanthenol from aerosol or gel excipients.

[Comparison of the antigenic spectrum A1, A2, and Ax erythrocytes: inhibition of mab with glucoconjugates of lipid and protein nature with different isoelectric properties].

The inhibition of monoclonal antibodies (MAbs) (anti-A1 2-24, anti-A 2-22, anti- 2-19, and anti- A 2-18; Workshop IV) by glycotopes (glycoconjugates) obtained by the enzymatic treatment of A1, A2, and Ax erythrocytes and by chloroform-methanol method from the membranes of these erythrocytes, followed by ion-exchange gel chromatography was evaluated. According to specificity and isoelectric properties, glycoconjugates (in the sequence of desorption from an anion exchanger) of glycoprotein (A(pr-00), A(pr-0), A(pr-1), A(pr-3)) and glycosphingolipid (A1p,00, A(1p-0), A(1p-1), A(1p-3), A(1p-3)) origin were identified. A1 erythrocytes showed the broad-spectrum inhibiting activity of glycoconjugates, which being at maximum with acid A(1p-00) and A(pr-3) (the ionic points of pH 6.55 and 6.45), as well as with A(lp-00) and A(1p-00) 1 The inhibition of A(pr-3) from A2 was significantly weaker that that from A1. An A(pr-3) fraction from Ax erythrocytes inhibited as strongly as in A1 and A2. The inhibition of A(pr-3p) from Ax either failed to develop at all (MAb 2-19) or turned out be weakened (MAbs 2-22 and 2-18). Thus, the cascade decrease in agglutinogenicity in the order of A1, A2, and Ax correlated with the reduction in the inhibiting capacity of A(pr-3) in all the study groups, including Ax.

A method for evaluation of volatile sulfur-containing substances in preparations for intravenous infusions.

Gas chromatographic method for measuring volatile sulfur compounds in solutions for intravenous infusions is proposed.

[Immunochromatographic analysis of 2,4-dichlorophenoxyacetic acid and simazine using monoclonal antibodies labelled with colloidal gold]. / Immunokhromatograficheskii analiz 2,4-dikhlorfenoksiukusnoi kisloty i simazina s ispol'zovaniem monoklonal'nykh antitel, mechennykh kolloidnym zolotom.

A method of the competitive immunochromatographic assay of the pesticides 2,4-D (2,4-dichlorophenoxyacetic acid) and simazine (2-chloro-4,6-bis(N-ethylamino)-1,2,5-triazine) in aqueous samples was developed. Monoclonal antibodies to these pesticides labeled with colloidal gold were used to visualize the results. The sensitivity of the 2,4-D and simazine assay is 12 ng/ml, and the time of analysis is 3-7 min. The method does not differ in sensitivity from the competitive EIA using conjugates of monoclonal antibodies to the pesticides with horseradish peroxidase; however, the time of the EIA is 1.5 h. The immunochromatographic method of the pesticide detection is available and simple and may be recommended for the development of assays of any other low-molecular compounds. The English version of the paper: Russian Journal of Bioorganic Chemistry, 2004, vol. 30, no. 2; see also http://www.maik.ru.

[A noninstrumental Immunoassay based on colloidal dyes]. / Neinstrumental'nyi immunoanaliz na osnove kolloidnykh krasitelei.

Detecting labels based on water dispersions of colloidal textile dyes were developed that are useful in various analytical and diagnostic test systems for a simple visual assessment of the assay. Colored water-insoluble particles of dyes were used for the sorptional immobilization of streptavidin on their surface. The resulting streptavidin-dye (STR-DYE) complexes possessed a high visualizing capacity and were used for the combined detection of pesticides (simazine and 2,4-dichlorophenoxyacetic acid) by noninstrumental immunoassay (DYE-comb-assay, competitive dot-immunoassay in the comb format). The detection limits and the duration of our DYE-comb-assay (4 ng/ml, 20-25 min), HRP-comb-assay (competitive dot-immunoassay in the comb format using the enzymic conjugate of STR with horseradish peroxidase) (16 ng/ml), and the traditional competitive ELISA (12-16 ng/ml, 1.5 h) were compared. This DYE-comb-assay is simple enough and can be used under field conditions.

Interplay between folding/unfolding and helix/coil transitions in giant DNA.

It has been well established that double-stranded DNA undergoes a melting, or helix/coil, transition into a single-stranded coil state with an increase in temperature. On the other hand, it has recently been found that, at a fixed temperature, long DNA, larger than several kilobase pairs, exhibits a discrete transition, or switching, between elongated and folded states, preserving its double-stranded structure, with the addition of various condensation agents, such as alcohol, hydrophilic polymer, multivalent cation, and cationic surfactant. In the present study, we examined the interplay between the folding/unfolding transition and the helix/coil transition in individual giant DNA molecules, by observing the conformation of single molecular chains with fluorescence microscopy. The results indicate that the helix-to-coil transition tightly cooperates with the unfolding transition in DNA.

[Isolation and purification of a protective protein from Propionibacterium freudenreichii subsp. Shermanii]. / Vydelenie i ochistka protektornogo belka iz kletok Propionibacterium freudenreichii substp. Shermanii.

A protein responsible for the protective and reactivating activities of two active fractions (AF1 and AF2) of the cells of Propionibacterium freudenreichii subsp. shermanii was isolated. The active fraction AF1 was obtained by fractional precipitation of the cell-free extract of propionic acid bacteria between 20 and 40% ammonium sulfate saturation, whereas fraction AF2 was precipitated between 60 and 80% saturation. Further fractionation of AF1 and AF2 by gel filtration on Sephacryl S-200 and by ion-exchange chromatography on DEAE-Sepharose yielded seven active subfractions, as revealed by testing for their protective activity on UV-inactivated cells of Escherichia coli. Analysis of subfraction AF2-2.5 by SDS-electrophoresis and HPLC showed that it contained an apparently homogeneous protein with a molecular mass of 44 +/- 2 kDa. The concentrational dependence of the protective activity of this protein was derived. Peptides of subfractions AF2-2.1 and AF2-2.2 with molecular masses lower than 15 kDa also exhibited protective activity.

[Simple immunoassays of pesticides based on the biotin-streptavidin system]. / Prostye immunokhimicheskie metody opredeleniya pestitsidov na osnove biotin-streptavidinovoi sistemy.

A simple method was developed for the preparation of a highly active streptavidin-peroxidase conjugate that enhances fourfold the sensitivity of bioassays. Using this conjugate, a quantitative assay of simazine and 2,4-dichlorophenoxyacetic acid (competitive ELISA) and a noninstrumental express method for simultaneous detection of these pesticides (dot-immunofiltration assay) were developed. The detection limit of the pesticides is 3-4 and 2 ng/ml and the duration of the assays is 1.5 h and 5 min for ELISA and dot-immunofiltration, respectively. The express method is easy and straightforward and enables the assay to be performed outside the laboratory.