ACUTE EFFECTS OF MOVEMENT VELOCITY ON BLOOD LACTATE AND GROWTH HORMONE RESPONSES AFTER ECCENTRIC BENCH PRESS EXERCISE IN RESISTANCE-TRAINED MEN

This study aimed to compare the effects of different velocities of eccentric muscle actions on acute blood lactate and serum growth hormone (GH) concentrations following free weight bench press exercises performed by resistance-trained men. Sixteen healthy men were divided into two groups: slow eccentric velocity (SEV; n = 8) and fast eccentric velocity (FEV; n = 8). Both groups performed four sets of eight eccentric repetitions at an intensity of 70% of their one repetition maximum eccentric (1RMecc) test, with 2-minute rest intervals between sets. The eccentric velocity was controlled to 3 seconds per range of motion for SEV and 0.5 seconds for the FEV group. There was a significant difference (P < 0.001) in the kinetics of blood lactate removal (at 3, 6, 9, 15, and 20 min) and higher mean values for peak blood lactate (P = 0.001) for the SEV group (9.1 ± 0.5 mM) compared to the FEV group (6.1 ± 0.4 mM). Additionally, serum GH concentrations were significantly higher (P < 0.001) at 15 minutes after bench press exercise in the SEV group (1.7 ± 0.6 ng · mL⁻¹) relative to the FEV group (0.1 ± 0.0 ng · mL⁻¹). In conclusion, the velocity of eccentric muscle action influences acute responses following bench press exercises performed by resistance-trained men using a slow velocity resulting in a greater metabolic stress and hormone response.     

A method of acoustic analysis for detection of bacteriophage-infected microbial cells

The dependence of the changes of physical parameters of the suspension of Azospirillum brasilense Sp7 cells infected by FAb-Sp7 bacteriophage on their number and exposure time was studied using a biological sensor based on a piezoelectric resonator with a lateral electric field. The change in the value of the analytical signal was recorded at 1 minute from the beginning of the infection of the cells by bacteriophage. The selectivity of the action of the FAb-Sp7 bacteriophage was studied for Azospirillum brasilense (strains Cd, Sp107, Sp245, Jm6B2, Br14, KR77, S17, S27, SR55, and SR75), A. lipoferum (strains Sp59b, SR65, and RG20a), A. halopraeferans Au4, Nitrospirillum amazonense Am14, Niveispirillum irakense (strains KBC1 and KA3) bacteria, as well as for heterologous bacteria of the genera Escherichia coli (strains XL-1 and B-878), Pseudomonas putida (strains C-11 and BA-11), and Acinetobacter calcoaceticum A-122. The limit of the reliable determination of the concentration of microbial cells during bacteriophage infection process was found: ~10⁴ cells/mL. At the same time, the presence of heterologous cell cultures (E. coli XL-1 cells) did not complicate the detection. It was shown that the method of electroacoustical analysis of cell suspensions can be used for the detection of microbial cells of Azospirillum infected by the FAb-Sp7 bacteriophage. The results are promising for the development of methods for determining and controlling the number of soil microorganisms.     

Biosensor for the detection of bacteriophages based on a super-high-frequency resonator

Azospirillum lipoferum Sp59b microbial cells were immobilized on the surface of thin polystyrene films modified in plasma from a high-frequency discharge of argon (13.56 MHz). The optimal conditions for immobilization, under which cell activity was maintained with respect to specific bacteriophages, were established. It was shown that it is possible to record the interaction of immobilized microbial cells and bacteriophages with a microwave-based resonant system (5–8.5 GHz). It was found that the biosensor made it possible to distinguish the interaction of bacterial cells with specific bacteriophages from the control, in which such interaction was absent. With the obtained super-high-frequency sensor, it was possible to determine the content of ΦAl-Sp59b bacteriophages in a suspension containing ~106 phages/mL. The analysis time was about 10 min. The viability of microbial cells after immobilization was also determined with this sensor. The results obtained with the use of the sensor on the basis of a super-high-frequency resonator have shown that it is promising for the development of methods to determine viral particles and the viability of microbial cells.     

Obtaining phage mini-antibodies and using them for detection of microbial cells with an electroacoustic sensor

Phage mini-antibodies to bacterial cells of strain Azospirillum brasilense Sp245 were obtained, and the possibility of using them for detection of microbial cells with a lateral field excited piezoelectric resonator was studied. It has been found that the frequency dependences of the real and imaginary parts of electrical impedance of such a resonator loaded with a suspension of A. brasilense Sp245 cells with the mini-antibodies differ significantly from the dependences of the resonator with a control cell suspension without mini-anti-bodies. The limit of possible determination of the concentration of microbial cells is found to be 10³ cells/mL upon interaction with mini-antibodies. It has been ascertained that detection of A. brasilense Sp245 cells with the aid of mini-antibodies is possible even in the presence of other cultures, for example, E. coli BL-Ril and A. brasilense Sp7. Therefore, it has been shown for the first time that detection of microbial cells with an electroacoustic sensor is feasible.     

Multiplicity of molecular forms and thermostability of Torula thermophila UzPT-1 protease]

Alkaline protease preparations with different ratio of molecular forms are isolated from cultural medium of thermophilic fungi Torula thermophila UzPT-1 by means of protein fractionation with (NJ/)2SO4 and gel filtration through Sephadex G-75. The enzyme preparations differ in their thermostability in water at 60 degrees C. High molecular weight oligomeric enzyme forms dissociate in water (at 2-4 degrees C) forming dimeric and monomeric forms. Disaggregation is accompanied by the change in the thermostability of the enzyme preparations. It is concluded that protease thermostability depends on the ratio of dimeric and monomeric forms of the preparation, and it is associated with the conformational state of the enzyme molecules, and it is associated with the conformational state of the enzyme molecules. Oligomeric forms do not dissociate in 1% sodium dodecylsulphate and in 6 M urea. Ca2+ produces dissociation of high molecular weight enzyme forms and the conformational transition into the thermostable state.     

Phage Antibodies as Bioreceptors for Ampicillin Detection

Applied Biochemistry and Microbiology - Ampicillin-specific antibodies were obtained using a sheep display library of scFv fragments (Griffin.1, UK). Ampicillin was determined by dot-immunoassay...