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51.
Demin Konstantin A. Refeld Aleksandr G. Bogdanova Anna A. Prazdnova Evgenya V. Popov Igor V. Kutsevalova Olga Yu. Ermakov Alexey M. Bren Anzhelica B. Rudoy Dmitry V. Chistyakov Vladimir A. Weeks Richard Chikindas Michael L. 《Probiotics and antimicrobial proteins》2021,13(4):926-948
Probiotics and Antimicrobial Proteins - Pathogenic Candida and infections caused by those species are now considered as a serious threat to public health. The treatment of candidiasis is... 相似文献
52.
Russian Journal of Plant Physiology - Changes in invertase activities were studied upon hardening of chilling-sensitive (Nicotiana tabacum L.) and cold-resistant (Arabidopsis thaliana Heynh. (L.))... 相似文献
53.
I. N. Bolotov A. A. Makhrov Yu. V. Bespalaya I. V. Vikhrev O. V. Aksenova P. E. Aspholm M. Yu. Gofarov A. N. Ostrovskii I. Yu. Popov I. S. Pal’tser M. Rudzite M. Rudzitis I. S. Voroshilova S. E. Sokolova 《Biology Bulletin》2013,40(2):221-231
This paper continues a discussion on the number of pearl mussel species of the genus Margaritifera in northern Europe. A biometric study of 1711 pearl mussel Margaritifera margaritifera shells from 15 rivers in Russia and Latvia (basins of the White and Baltic seas) has been conducted. All the examined samples fall into two groups: the northern group (with the shells more flattened on average, f. margaritifera) and the southern one (with more convex shells, f. elongata); the boundary between these groups is at 63° N. Analysis of intrapopulation variation has shown that the samples contain individuals that correspond to f. margaritifera, f. elongata, and f. borealis. However, any hiatus between these forms is absent in all the samples, and individuals belonging to two intermediate forms are rather frequent. The hypothesis on the species specificity of the shell valve frontal section has not been confirmed based on examination of large shell samples. The pearl mussels inhabiting rivers of Northern Europe belong to a single species, M. margaritifera. 相似文献
54.
Alexander V. Kachur Anatoliy V. Popov Joel S. Karp E. James Delikatny 《Cell biochemistry and biophysics》2013,66(1):1-5
We report a reaction of direct electrophilic fluorination of phenolsulfonphthalein at mild conditions. This reaction affords the synthesis of novel positron-emitting 18F-labeled pH indicators. These compounds are useful for non-invasive in vivo pH measurement in biological objects. 相似文献
55.
D. V. Popov R. A. Zinovkin E. M. Karger O. S. Tarasova O. L. Vinogradova 《Human physiology》2013,39(2):190-195
It is well recognized that PGC-1α protein is a key regulator of mitochondrial biogenesis. Mechanical and metabolic perturbations in a skeletal muscle during and after aerobic exercise lead to an increased expression of PGC-1α gene. This increased expression of PGC-1α gene after exercise depends on the relative workload intensity and does not depend on the fitness level. The goal of this study was to compare mRNA expression of PGC-1α, TFAM, and TFB2M regulators of mitochondrial biogenesis and FOXO1 and Atrogin-1 proteolysis-related genes in a skeletal muscle of untrained and trained men after aerobic exercise with the same relative workload. This study showed that PGC-1α gene expression after exercise was the same in the two groups, but the expression of TFAM and TFB2M genes was higher in untrained muscles than in trained ones. In contrast, the expression of FOXO1 and Atrogin-1 genes increased only in the muscles of trained men. 相似文献
56.
The basic assumption of the analysis is that the stratigraphical change of relative abundance of the small mammal species is a phenomenon due to a certain number of environmental factors. In order to reveal these factors and to make some palaeoclimatic reconstructions the following approaches have been used: 1. Analysis of intrinsic structure of the initial data by using principal component analysis (PCA)—delimitation of recurrent groups of species and ordination of assemblages; 2. Extension backward in time of known ecological preference of taxa, forming a particular recurrent group; 3. Comparison of the results with the analysis of assemblages from “known”; (Holocene) environment. On the basis of ecological appearance of particular recurrent groups it is assumed that the main factors are temperatures and effective moisture. The reconstructed values for these environmental factors obtained on the basis of the Holocene recurrent groups of small mammals shows similarity to the recent climate in the area. 相似文献
57.
A. M. Popov A. N. Osipov E. A. Korepanova O. N. Krivoshapko A. A. Artyukov 《Biophysics》2013,58(5):607-615
Rosmarinic acid is found in many species of different families of higher plants and its chemical structure is phenol propanoid with various biological activity. In this paper, we conducted a comparative study of antioxidant (radical-scavenging) properties of rosmarinic acid in systems of 2,2tāzo-bis(2-methylpropionamidin)dihydrochloride-luminol and hemoglobin-hydrogen peroxide-luminol, determined its protective potential in preventing peroxidation of linoleic acid, and evaluated the effect on the permeability of planar bilayer lipid membranes. Linoleic acid peroxidation was assessed by iron-thiocyanate method. In these studies, trolox was used as a reference antioxidant, and ascorbic acid, and dihydroquercetin were taken as standards. Rosmarinic acid is significantly superior to trolox, ascorbic acid and dihydroquercetin in the tests for antioxidant activity in the systems studied, as well as in inhibition of linoleic acid peroxidation. According to their activity the investigated substances can be arranged in the following order: rosmarinic acid > dihydroquercetin trolox > ascorbic acid. Rosmarinic acid does not cause significant changes in the permeability of planar bilayer membranes in a dose range of 0.5 to 10 μg/mL. Antioxidant activity of rosmarinic acid is due to the neutralization of reactive oxygen species and/or luminol radicals generated in model systems. The observed features of the antioxidant and membrane activity of rosmarinic acid, which may underlie the previously mentioned pharmacological effects are discussed. 相似文献
58.
Myung-Chul Chung Aarthi Narayanan Taissia G. Popova Fatah Kashanchi Charles L. Bailey Serguei G. Popov 《Biochemical and biophysical research communications》2013,430(1):125-130
Bacillus anthracis, a causative agent of anthrax, is able to germinate and survive within macrophages. A recent study suggested that B. anthracis-derived nitric oxide (bNO) is a key aspect of bacterial defense that protects bacterial DNA from oxidative burst in the macrophages. However, the virulent effect of bNO in host cells has not been investigated. Here, we report that bNO contributes macrophage killing by S-nitrosylation of bioenergetic-relating proteins within mitochondria. Toxigenic Sterne induces expression of the bnos gene and produces bNO during early stage of infection. Nitroso-proteomic analysis coupled with a biotin-switch technique demonstrated that toxigenic infection induces protein S-nitrosylation in B. anthracis-susceptible RAW264.7. For each target enzyme tested (complex I, complex III and complex IV), infection by B. anthracis Sterne caused enzyme inhibition. Nω-nitro-l-arginine methyl ester, a NO synthase inhibitor, reduced S-nitrosylation and partially restored cell viability evaluated by intracellular ATP levels in macrophages. Our data suggest that bNO leads to energy depletion driven by impaired mitochondrial bioenergetic machinery that ultimately contributes to macrophage death. This novel mechanism of anthrax pathogenesis may offer specific approach to the development of therapeutics. 相似文献
59.
Gergana Gacheva Liliana Gigova Natalia Ivanova Ivan Iliev Reneta Toshkova Elena Gardeva Vesselin Kussovski Hristo Najdenski 《Journal of applied phycology》2013,25(1):183-194
The cytotoxic, antibacterial, and antifungal activities of cyanobacterium Gloeocapsa sp. strain Gacheva 2007/R-06/1 were investigated and the possibility for an enhancement of these activities by changing the culture conditions evaluated. Fatty acids of this cyanobacterium were found to be active against Streptococcus pyogenes. Exopolysaccharides inhibited the growth of both Gram-positive and Gram-negative bacteria and the fungus Candida albicans. Both exopolysaccharides and fatty acid mixtures also significantly decreased the viability of human cervical carcinoma cells, HeLa. Greater biological activities were exhibited by Gloeocapsa sp., cultured at suboptimal temperatures (15–26°C) than at optimal and supraoptimal ones. In comparison with higher light intensity, the low-light cultivation stimulated the cytotoxicity of the fatty acids. In general, low temperatures decreased the growth of Gloeocapsa sp., but promoted its biological activity. Prolonged cultivation also had a beneficial impact on the bioactivity. Compared to 4 days, the 17-day cultivation resulted in fourfold higher antibacterial and antifungal activities of exopolysaccharides and more than twice increases in their cytotoxicity. The study revealed that this cyanobacterial isolate is a new source of natural products with potential for pharmacological and medical applications. 相似文献
60.
Inter‐Fullerene Electronic Coupling Controls the Efficiency of Photoinduced Charge Generation in Organic Bulk Heterojunctions
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Bryon W. Larson Obadiah G. Reid David C. Coffey Stanislav M. Avdoshenko Alexey A. Popov Olga V. Boltalina Steven H. Strauss Nikos Kopidakis Garry Rumbles 《Liver Transplantation》2016,6(24)
Photoinduced charge generation (PCG) dynamics are notoriously difficult to correlate with specific molecular properties in device relevant polymer:fullerene organic photovoltaic blend films due to the highly complex nature of the solid state blend morphology. Here, this study uses six judiciously selected trifluoromethylfullerenes blended with the prototypical polymer poly(3‐hexylthiophene) and measure the PCG dynamics in 50 fs–500 ns time scales with time‐resolved microwave conductivity and femtosecond transient absorption spectroscopy. The isomeric purity and thorough chemical characterization of the fullerenes used in this study allow for a detailed correlation between molecular properties, driving force, local intermolecular electronic coupling and, ultimately, the efficiency of PCG yield. The findings show that the molecular design of the fullerene not only determines inter‐fullerene electronic coupling, but also influences the decay dynamics of free holes in the donor phase even when the polymer microstructure remains unchanged. 相似文献