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111.
The secondary peptide metabolites produced by the Trichoderma asperellum strain F-1087 were isolated, and their properties were studied. It has been shown these metabolites at concentrations of 0.08 and 0.02 mg/mL inhibit the human prostate cancer cell line by 97 and 34%, respectively.  相似文献   
112.
In warm-blooded vertebrates, the α- and β-globin genes are organized in domains of different types and are regulated in different fashion. In cold-blooded vertebrates and, in particular, the tropical fish Danio rerio, the α- and β-globin genes form two gene clusters. A major D. rerio globin gene cluster is in chromosome 3 and includes the α- and β-globin genes of embryonic-larval and adult types. The region upstream of the cluster contains c16orf35, harbors the main regulatory element (MRE) of the α-globin gene domain in warm-blooded vertebrates. In this study, transient transfection of erythroid cells with genetic constructs containing a reporter gene under the control of potential regulatory elements of the domain was performed to characterize the promoters of the embryonic-larval and adult α- and β-globin genes of the major cluster. Also, in the 5th intron of c16orf35 in Danio rerio was detected a functional analog of the warm-blooded vertebrate MRE. This enhancer stimulated activity of the promoters of both adult and embryonic-larval α- and β-globin genes.  相似文献   
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114.
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   

115.
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   
116.
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   
117.
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   
118.
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   
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120.
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   
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