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A comparative analysis of structural variability of C-bands on chromosomes 1, 9, 16 and Y was conducted in 50 phenotypically normal adults and 25 couples with repeated spontaneous abortions. Reduction of both the total amount of heterochromatin in the cell and the lengths of these regions on chromosomes 1, 9, and 16 is revealed in the group of pathology. No differences were found in the lengths of C-bands on Y chromosome. 相似文献
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Biochemistry (Moscow) - Stress negatively affects processes of synaptic plasticity and is a major risk factor of various psychopathologies such as depression and anxiety. HOMER1 is an important... 相似文献
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Pleshakova Y. V. Zelenova N. A. Ngun C. T. Reshetnikov M. V. 《Biology Bulletin》2021,48(10):1761-1770
Biology Bulletin - Abstract—In a long-term model experiment, the abundance dynamics of soil microorganisms was studied as affected by the pollution of southern chernozem soils with various... 相似文献
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Reshetnikov Yu. S. Sterligova O. P. Anikieva L. V. Koroleva I. M. 《Journal of Ichthyology》2020,60(3):491-502
Journal of Ichthyology - Wide adaptive capabilities of fish introduced into new water bodies are shown by the example of vendace Coregonus albula and European smelt Osmerus eperlanus. Analysis of... 相似文献
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Mansurova GV Pogrebnaia OG Ponomarev GV Reshetnikov AV Potapenko AIa Bezdetnaia LN Gimya F 《Biofizika》2003,48(2):251-255
A comparative analysis of the ability of 4-(1-methyl-3-hydroxybutyl)-deuteroporphyrin-IX (I) and 2,4-di-(1-methyl-3-hydroxybutyl)-deuteroporphyrin-IX (II) to photosensitize hemolysis of human erythrocytes was performed. The photohemolytic efficiency of dye I was shown to be about 60 times higher than that of dye II. It was found that a part of each dye tightly binds to erythrocyte membranes and is not removed by washing. A method for estimating the share of the dye tightly bound to the membrane (beta) was proposed, which takes into account the shielding effect produced by the free dye and the photohemolytic efficiency of the bound dye. It was shown that the beta values for dyes I and II are 86 and 61% and correlate with the coefficients of distribution of the dyes in the octanol/water system (20.7 and 17.0, respectively). 相似文献
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E. A. Popowich A. P. Firsov T. Y. Mitiouchkina V. L. Filipenya S. V. Dolgov V. N. Reshetnikov 《Plant Cell, Tissue and Organ Culture》2007,90(3):237-244
Transgenic plants of hyacinth (Hyacinthus orientalis L.) cvs. Edisson and Chine Pink have been obtained by Agrobacterium-mediated transformation. Leaf explants of the both hyacinth cultivars regenerated shoots on MS medium containing 2.2 μM BAP
and 0.3 μM NAA at a frequency of 95%. A. tumefaciens strain CBE21 carrying binary vector pBIThau35 was used for transformation. Plasmid pBIThau35 has been produced by cloning
preprothaumatin II cDNA into pBI121 instead of uidA gene. Inoculated leaf explants formed calli and shoots at high frequency on selective medium with 100 mg l−1 kanamycin. Four hyacinth transgenic lines of cv. Chine Pink and one line of cv. Edisson have been selected on medium containing 200 mg l−1 kanamycin. The insertion of thaumatin II gene into hyacinth genome has been confirmed by PCR-analysis. All transgenic plants
expressed substantial amounts of thaumatin II (between 0.06 and 0.28% of the total soluble protein). Hyacinth transgenic lines
were assayed for resistance to the pathogenic fungi Fusarium culmorum and Botrytis cinerea. There were no significant differences between nontransformed control and transgenic leaves of both cultivars. At the same
time the bulbs of the transgenic line Н7401 cv. Chine Pink showed the higher level of resistance to B. cinerea, the bulbs of the transgenic line Н7404 were more resistant to F. culmorum. In both cases the signs of the fungal disease were developed more slowly. The resistance of the bulbs cv. Edisson line to these fungi was not changed. All transgenic hyacinth plant were successfully transferred to soil for further evaluation. 相似文献
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Reshetnikov AS Mustakhimov II Khmelenina VN Trotsenko YA 《Biochemistry. Biokhimii?a》2005,70(8):878-883
L-2,4-Diaminobutyrate (DAB) acetyltransferase (DABAcT) catalyzes one of the key reactions of biosynthesis of the bacterial osmoprotectant ectoine--acetylation of L-2,4-DAB yielding Ngamma-acetyl-2,4-DAB. Gene ectA encoding DABAcT was cloned from DNA of the halotolerant methanotroph Methylomicrobium alcaliphilum 20Z and expressed in Escherichia coli with an additional six His residues at the C-terminus. Homogeneous enzyme preparation with specific activity 200 U/mg was obtained by affinity metal-chelating chromatography. DABAcT was found to be a homodimer with molecular mass 40 kD. The enzyme is most active at pH 9.5 and 20 degrees C, and its activity increased threefold in the presence of 0.1-0.2 M NaCl or 0.2 M KCl. The Km values of recombinant DABAcT measured at the optimal pH and temperature in the presence of 0.2 M KCl were 460 and 36.6 microM for L-2,4-DAB and acetyl-CoA, respectively. The enzyme is specific for L-2,4-DAB and acetyl-CoA and is also active against propionyl-CoA (20%). Zn2+ and Cd2+ at 1 mM concentration completely inhibit the recombinant enzyme; 10 mM ATP inhibits 26% of the enzyme activity, whereas EDTA, o-phenanthroline, ADP, NAD(P), and NAD(P)H do not significantly effect the enzyme activity. The possible participation of DABAcT in regulation of ectoine biosynthesis in M. alcaliphilum 20Z is discussed. 相似文献
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Uzdensky AB Dergacheva OY Zhavoronkova AA Reshetnikov AV Ponomarev GV 《Life sciences》2004,74(17):2185-2197
Chlorin e(6) and its derivatives are promising sensitizers for photodynamic therapy (PDT). In order to compare the photodynamic effects of 8 novel derivatives of chlorin e(6) and to explore some mechanisms of their effects at the cellular level, we studied PDT-induced changes in bioelectric activity of crayfish mechanoreceptor neuron that was used as a sensitive experimental model. Neurons were insensitive to red laser irradiation (632.8 nm; 0.3 W/cm(2)) or to photosensitizers alone, but changed firing rate and died under the photodynamic effect of nanomolar concentrations of sensitizers. The dynamics of neuron responses depended on photosensitizer type and concentration. The dependence of neuron lifetime on photosensitizer concentration allowed comparing efficiencies of different photosensitizers. Radachlorin was the most potent photosensitizer comparable with mTHPC. High photodynamic efficiency of some chlorin e(6) derivatives was related to weak dependence of neuron lifetime on sensitizer concentration, indicating to the initiation of 2-3 secondary processes such as free radical membrane damage by one absorbed photon. Photodynamic efficiency of sensitizers depended on amphiphilicity influencing their intracellular localization. 相似文献
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Andrey N. Reshetnikov 《Hydrobiologia》2003,510(1-3):83-90
The fish rotan (Perccottus gleniiDybowski) was accidentally introduced into European Russia from the Amur River basin. Rotan is capable of colonising small waterbodies – favourable breeding sites of native amphibians. To reveal its influence on the native aquatic fauna, monitoring of small waterbodies has been carried out since 1994 in the region of Lake Glubokoe Reserve (Moscow Province, Russia). The fish's diet includes a wide range of animal species of all trophic levels. Rotan considerably decreases the species richness of aquatic macroinvertebrates and larval amphibians. As a rule, most amphibian species (Triturus cristatus, T. vulgaris, Rana temporaria, R. arvalis, R. lessonae) and the fish Carassius carassius failed to breed successfully in ponds inhabited by rotan. In contrast, the toad Bufo bufo bred successfully in such sites because its larvae are distasteful to rotan. Rotan–amphibian interactions are discussed. 相似文献