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111.
Katerina Stambolieva Dorina Petrova Mariya Irikeva 《Somatosensory & motor research》2017,34(2):129-133
Purpose: To evaluate the effectiveness of 8-week low-frequency plantar vibration training on patients with sensorimotor diabetic peripheral neuropathy (DPN).
Participants: Twelve patients took part in the investigation.
Results: An increase of the nerve conductive velocity of soral and peroneal nerves of feet, increased postural stability, and disappearance of the pain and tingling were observed.
Conclusion: The obtained results provide evidence for beneficial effects of 8-week plantar vibration training in patients with DPN. 相似文献
112.
A.?K.?Velichko N.?V.?Petrova S.?V.?RazinEmail author O.?L.?Kantidze 《Molecular Biology》2017,51(1):130-135
Reactions of genetically identical cells to various exogenous and endogenous stimuli can vary significantly. One of the main factors of this non-genetic cellular heterogeneity is the cell cycle. The most convenient way to study the subcellular processes depending on the cell cycle stage is the synchronization of the cells. Toxic inhibitors of DNA replication and/or mitotic spindle assembly are typically used to synchronize cells. It is important to accurately select the synchronization method for a particular experiment. In this study, we performed a comparative analysis of the synchronization methods of normal and transformed human cells, paying special attention to the accuracy of synchronization and toxicity of the methods used. 相似文献
113.
Kiril Tishinov Nikolina Stambolieva Svetla Petrova Boris Galunsky Peter Nedkov 《Acta Physiologiae Plantarum》2009,31(1):199-205
The sunflower seed (Helianthus annuus L.) major peptidase was purified to molecular homogeneity. It is an 80 kDa enzyme with pI of 4.6 and optimal activity at
pH 7.5–8.0 and 45–50°C. It is a thiol-dependent aminopeptidase hydrolyzing peptides in a step-by-step manner as cleaving after
the N-terminal amino acid residue of the substrate. It requires substrate acyl parts with a free amino group in either α-
or β-position and l-configuration of the adjacent carbon atom. The enzyme prefers amino acid residues with bulky hydrophobic side chains at P1-position and its catalytic efficacy is affected by the structure of both P1 and P1′ parts of the substrate. 相似文献
114.
T. I. Ivanova N. P. Kuz’mina S. V. Petrova A. P. Chevychelov A. P. D’yachkovskii 《Contemporary Problems of Ecology》2009,2(1):27-32
Specific features of soil microbial colonies in industry-affected mountainous-taiga permafrost landscapes in the El’kon uranium ore district on the territory of South Yakutia are revealed: a high number of ecological trophic groups of microorganisms (2.0 × 103 ?7.6 × 107 cells/g), comparable to the density of microbes in meadow steppe soils of Central Yakutia and a special nature of their distribution over the soil profile depending on the uranium content of the soil. In the soil of a uranium-contaminated pit, the number of individuals in all examined groups of microorganisms increases with a decrease in uranium content to 161 ppm. In the remaining samples of this pit, the disappearance of microorganisms or their decline by one or two orders of magnitude with increasing uranium content of the soil is observed. A different situation is with microorganisms in the soil of native landscape: Their numbers remain there high over the entire soil profile. Estimated correlations between the number of individuals of the main ecological trophic groups of microorganisms and factors such as uranium content, temperature, and humidity of soil shows that the relationship with the concentration of this radionuclide was strongly negative (r = ?0.6) in the radiation-contaminated alluvial soil, while a strict relationship between the number of microorganisms and soil temperature was revealed for the uncontaminated soil (r = ±1). 相似文献
115.
I. Yu. Petrova A. A. Bulgakov E. L. Nazarenko E. V. Shamshurina S. S. Kobelev M. G. Eliseikina 《Russian Journal of Marine Biology》2009,35(2):171-177
A mannan-binding lectin activity was revealed in the coelomic fluid of the following echinoderm species inhabiting the coastal areas of the Sea of Japan, the holothurian Eupentacta fraudatrio, sea urchins Echinocardium cordatum, Strongylocentrotus nudus and S. intermedius, brittle star Amphipholis kochii, sea stars Asterina pectinifera, Lethasterias fusca, Lysastrosoma anthosticta, and Distolasterias nipon. It was shown that, concurrently with the general pattern of lectin interaction with branched bacterial mannans, there were also distinctions caused by the fine carbohydrate specificity of lectins. The obtained data preconditioned the further study of physical and chemical properties and structural features of the echinoderm MBL and the revelation of their role in the formation of the adaptive immune response and in other biological processes. 相似文献
116.
117.
Tatiana Petrova Vladimir Y. Lunin Isabelle Hazemann André Mitschler Andrzej Joachimiak 《Journal of molecular biology》2009,387(5):1092-825
X-rays interact with biological matter and cause damage. Proteins and other macromolecules are damaged primarily by ionizing X-ray photons and secondarily by reactive radiolytic chemical species. In particular, protein molecules are damaged during X-ray diffraction experiments with protein crystals, which is, in many cases, a serious hindrance to structure solution. The local X-ray-induced structural changes of the protein molecule have been studied using a number of model systems. However, it is still not well understood whether these local chemical changes lead to global structural changes in protein and what the mechanism is.We present experimental evidence at atomic resolution indicating the movement of large parts of the protein globule together with bound water molecules in the early stages of radiation damage to the protein crystal. The data were obtained from a crystal cryocooled to ~ 100 K and diffracting to 1 ?. The movement of the protein structural elements occurs simultaneously with the decarboxylation of several glutamate and aspartate residues that mediate contacts between moving protein structural elements and with the rearrangement of the water network. The analysis of the anisotropy of atomic displacement parameters reveals that the observed atomic movements occur at different rates in different unit cells of the crystal. Thus, the examination of the cooperative atomic movement enables us to better understand how radiation-induced local chemical and structural changes of the protein molecule eventually lead to disorder in protein crystals. 相似文献
118.
E. V. Daev M. V. Petrova L. S. Onopa V. A. Shubina T. S. Glinin 《Russian Journal of Genetics》2017,53(10):1105-1112
It is shown by single-cell gel electrophoresis that the exposure of CBA mouse males with pheromone 2,5-dimethylpyrazine for 4 or 24 h increases DNA damage level in interphase nuclei of bone marrow cells. The results may reflect the work of a mechanism of formation of chromosomal aberrations and other mitotic disturbances, detected at the stage of ana-telophase, the frequency of which in dividing bone marrow cells increased after similar pheromonal exposure. The comparison of the damaged cell distribution types is proposed as an approach to analysis of comet assay data. The significance of the revealed effects on the immune system in the recipient organism is discussed. 相似文献
119.
Petrova NS Meschaninova MI Venyaminova AG Zenkova MA Vlassov VV Chernolovskaya EL 《FEBS letters》2011,585(14):2352-2356
The thermodynamic properties of siRNA duplexes are important for their silencing activity. siRNAs with high thermodynamic stability of both the central part of the duplex and in the whole, usually display low silencing activity. Destabilization of the central part of the siRNA duplex could increase its silencing activity. However, mismatches located in the central part of the duplex could substantially decrease the amount of RNAi efficacy, hindering active RISC formation and function. In this study, we examined the impact of duplex destabilization by nucleotide substitutions in the central part (7-10 nt counting from the 5'-end of the antisense strand) of the nuclease-resistant siRNA on its silencing activity. 相似文献
120.
The interaction of Pseudomonas aeruginosa with surfaces has been described as a two-stage process requiring distinct signaling events and the reciprocal modulation of small RNAs (sRNAs). However, little is known regarding the relationship between sRNA-modulating pathways active under planktonic or surface-associated growth conditions. Here, we demonstrate that SagS (PA2824), the cognate sensor of HptB, links sRNA-modulating activities via the Gac/HptB/Rsm system postattachment to the signal transduction network BfiSR, previously demonstrated to be required for the development of P. aeruginosa. Consistent with the role of SagS in the GacA-dependent HtpB signaling pathway, inactivation of sagS resulted in hyperattachment, an HptB-dependent increase in rsmYZ, increased Psl polysaccharide production, and increased virulence. Moreover, sagS inactivation rescued attachment but abrogated biofilm formation by the ΔgacA and ΔhptB mutant strains. The ΔsagS strain was impaired in biofilm formation at a stage similar to that of the previously described two-component system BfiSR. Expression of bfiR but not bfiS restored ΔsagS biofilm formation independently of rsmYZ. We demonstrate that SagS interacts directly with BfiS and only indirectly with BfiR, with the direct and specific interaction between these two membrane-bound sensors resulting in the modulation of the phosphorylation state of BfiS in a growth-mode-dependent manner. SagS plays an important role in P. aeruginosa virulence in a manner opposite to that of BfiS. Our findings indicate that SagS acts as a switch by linking the GacA-dependent sensory system under planktonic conditions to the suppression of sRNAs postattachment and to BfiSR, required for the development of P. aeruginosa biofilms, in a sequential and stage-specific manner. 相似文献