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151.
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G A Belokrylov I V Molchanova O Ia Popova 《Biulleten' eksperimental'no? biologii i meditsiny》1989,108(11):584-587
In experiments on mice and in vitro the influence of neurotensin pentagastrin and thymopentin on the immune response, the phagocytosis of staphylococcus aureus by polymorphoneutrophil leucocytes and enzymatic activity of these cells by NBT-test were investigated. It was shown that neurotensin and thymopentin increase enzymatic and phagocytic function of polymorphoneutrophil leucocytes. Pentagastrin, as well as thymopentin stimulates the immune response, enzymatic but not phagocytic function of polymorphoneutrophil leucocytes. Immunostimulating effect of the studied peptides was realized by facility differentiation of mouse bone marrow cells into T-lymphocytes and by the interaction of the peptides with T-cells. 相似文献
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156.
Ahmed Salama Elena Popova Maxwell P. Jones Mukund R. Shukla Nathan S. Fisk Praveen K. Saxena 《In vitro cellular & developmental biology. Plant》2018,54(1):69-78
In this study conservation of Castilleja levisecta Greenm., a globally endangered species was addressed through in vitro cryopreservation of shoot tips. In vitro cultures were successfully established using seedlings received from British Columbia, Canada. Shoot tips excised from in vitro propagated plants were cryopreserved using a droplet-vitrification method following optimization of individual protocol steps such as pre-culture, treatment with vitrification solutions, and unloading. The highest plant regrowth after cryopreservation (66%) was achieved when shoot tips were pre-cultured in 0.3 M sucrose for 17 h followed by 0.5 M sucrose for 4 h, incubated in an osmo-protectant solution (17.5% [v/v] glycerol and 17.5% [w/v] sucrose) for 20 min, exposed to vitrification solution A3 (37.5% [v/v] glycerol plus 15% [v/v] dimethylsulfoxide (DMSO) plus 15% [v/v] ethylene glycol (EG) plus 22.5% [w/v] sucrose) on ice for 40 min, and unloaded in 0.8 M sucrose solution for 30 min. Healthy plants were developed from cryopreserved shoot tips and propagated in vitro using nodal segments. Plants derived from in vitro culture and from cryopreserved tissues were successfully rooted and acclimated in a greenhouse with 100% survival rate. Acclimatized plants were reintroduced in a naturalized propagation area at the Conservation Nursery at Fort Rodd Hill, Canada. Twenty of 94 reintroduced plants (21%) survived the transit from lab to field and some had started to flower. This is the first report for cryopreservation of C. levisecta, an important step in conserving and re-introducing this critically imperiled species in nature. 相似文献
157.
Tatyana V. Popova Hamda Khan Alexey S. Chubarov Vladimir A. Lisitskiy Natalya M. Antonova Andrey E. Akulov Oleg B. Shevelev Evgenii L. Zavjalov Vladimir N. Silnikov Saheem Ahmad Tatyana S. Godovikova 《Bioorganic & medicinal chemistry letters》2018,28(3):260-264
Human serum albumin is playing an increasing role as a drug carrier in clinical settings. Biotin molecules are often used as suitable tags in targeted anti-tumor drug delivery systems. We report on the synthesis and properties of a new multimodal theranostic conjugate based on an anti-cancer fluorinated nucleotide conjugated with a biotinylated dual-labeled albumin. Interestingly, in vitro and in vivo study revealed stronger anti-tumor activity of the non-tagged theranostic conjugate than that of the biotin-tagged conjugate, which can be explained by decreased binding of the biotin-tagged conjugate to cellular receptors. Our study sheds light on the importance of site-specific albumin modification for the design of albumin-based drugs with desirable pharmaceutical properties. 相似文献
158.
This work is directed at continuous studies of cyclicity of long-term (1980–2010) population dynamics of odonates in the basin of Lake Chany (in the south of Western Siberia). Four sympatric species of the genus Sympetrum have been investigated by spectral analysis method. The cycle spectra of population dynamics have been constructed for each species; the basic parameters of these cycles (period, phase, and power) have been calculated. Special number cycles have been found for each species. Interspecies differences increased in the direction from high to low frequencies of the spectrum. In the cases of similar cycles, interspecies differences have been shown in the ratio of cycle powers and/or phases: identical phases can indicate the ability of species to increase their number synchronously with any of close species; different phases can indicate the possibility of a small-numbered species to reach its maximum number against the minimum number of numerous species. A comparison of sympatric species spectra of the genera Coenagrion and Sympetrum has led to the conclusion that, the more similarity there is in environmental standards among species inside a genus (as for Sympetrum), the more specific the species frequency spectra are. All species of the genus Sympetrum can synchronize their number fluctuations with 2- to 3 and 4- to 5-year fluctuations of the local climate. Also specific synchronization with important nature-climatic rhythms was found for each species: for S. danae, with an 18-year rhythm of the level of Lake Chany and with a 16-year rhythm of June temperatures; for S. flaveolum, with a 24-year Brickner cycle, with an 8-year cycle of rainfall, and with a 28-year cycle of April and May temperatures; for S. vulgatum, with a 40- to 42-year cycle of the level of Lake Chany, with 12-year cycle of rainfall, and with a 7-year cycle of April and June temperatures; and for S. sanguineum, with a 7-year cycle of April and June temperatures. Perhaps the adaptation mechanism of species to each other and to environments is enclosed in the cyclicity of long-term fluctuations of species number. 相似文献
159.
Svetlana E Medvedeva Anatoly Boyandin Yuly Lankin Dmitry Kotov Emma Rodicheva Lyudmila Popova 《Luminescence》2005,20(2):90-96
The Institute of Biophysics SB RAS hosts and maintains a specialized collection of luminous bacteria (CCIBSO 836) containing over 700 strains isolated in various regions of the world's oceans. The culture collection is a source of lux genes and biologically active substances. The wide application of bioluminescence in medicine and ecology has given importance to analysing information on the structure and functioning of bioluminescence systems in natural and transgenic microorganisms, as well as on their features that are closely interrelated with bioluminescence. The aims of our BIOLUMBASE database are: gathering information on microorganisms with lux genes, their analysis and free access, and distribution of this data throughout the global network. The database includes two sections, natural and transgenic luminous microorganisms, and is updated by our own experimental results, the published literature and internet resources. For the future, a publicly available internet site for BIOLUMBASE is planned. This will list the strains and provide comprehensive information on the properties and functions of luminous bacteria, the mechanisms of regulation of bioluminescence systems, constructs with lux genes, and applications of bioluminescence in microbiology, ecology, medicine and biotechnology. It is noteworthy that this database will also be useful for evaluation of biological hazards of transgenic strains. Users will be able to carry out bibliographic and strain searches starting from any feature of interest. 相似文献
160.
A. M. Bezborodov T. A. Popova D. N. Chermenskii L. V. Andreyev 《Folia microbiologica》1973,18(3):223-228
Acid-soluble (“free”) nucleotides, nucleosides and bases were analyzed in the mycelium and in the culture filtrate of the
fungusPenicillium sizowi, using micro-thin-layer chromatography on alumina and densitometry of the zones of the individual components. It was found
that the levels of the various components underwent complicated changes, the corresponding curves exhibiting from one to three
maxima which occur at different periods of cultivation. It was observed that a substantial amount of nucleotides, nucleosides
and bases occurs in the medium as early as at the beginning of the exponential phase of growth. An attempt was made to elucidate
some peculiarities of the nucleotide pool ofPenicillium species, using enzymes responsible for the individual transformations of nucleotides, nucleosides and bases. 相似文献