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1.
The ergosterol and lecithin absorption IR-spectra were studied in a nonpolar anhydrous medium. The thermodynamical and spectral characteristics of dimeric associates and the enthalpy value for trimeric associates of this sterol are determined. Thermodynamical and spectral parameters of ergosterol intermolecular associates with lecithin in a nonpolar anhydrous medium are found. It is established that the intermolecular interaction of lecithin with ergosterol occurs according to the mechanism of hydrogen bond. A conclusion is drawn that the presence of binary bonds and methyl groups in the cyclic and aliphatic parts of the sterol molecule affects greatly the structure of the model membrane and its strength. It is shown that under conditions of the experiment the oxygen of the phosphate group contributes to formation of the molecular associates of lecithin with sterols and not that of the carbonyl group. The obtained experimental data may be at use when studying structural disturbances of native membranes in norm and with different pathologies. 相似文献
2.
G F Shereme'teva E Z Kocharian M M Morozova 《Arkhiv anatomii, gistologii i émbriologii》1989,97(8):18-25
Dynamics of reparative regeneration of the sutural anastomosis of the abdominal aorta has been studied in 90 white mice during the time from 1 day up to 1 year. The operation has been performed by means of microsurgical technique. Histological, histochemical, electron microscopic and radioautographic (3H-thymidine and 3H-uridine labelling) methods have been used. By the 7th day fibrin is organized on the adventitia, the scar along the resection line is formed, endothelial lining and middle layer of the vascular wall are restored. As sources of regeneration in the anastomosis serve cellular elements preserved in the lesion margins. Further maturation of the formed structures and formation of the initial thickening by migrating smooth muscle cells of the middle layer take place. Completeness and typicity depend on preservation of the elastic carcass in the middle layer and adventitia. 相似文献
3.
R P Morozova V A Kokunin I A Nikolenko N V Kanivets M V Stefanov 《Ukrainski? biokhimicheski? zhurnal》1988,60(4):18-24
DEAE-cellulose chromatography and SDS-PAAG electrophoresis were used to study proteins from endoplasmic reticulum of smooth and rough enterocyte membranes in the vitamin D-replete and deficient rat. The membrane-bound vitamin-D-dependent protein with a molecular weight of 21-25 kDa is shown to consist of the endoplasmic reticulum of smooth membranes. The intensive binding of calcium by these membranes is established. 相似文献
4.
R. Yu. Kiselyova M. A. Myagkova I. V. Shakir E. A. Bryun V. S. Morozova 《Applied Biochemistry and Microbiology》2011,47(7):707-710
Enzyme-linked immunosorbent assay (ELISA) for detection of amphetamines in urine was developed. The conditions for ELISA using an antigen obtained from the derivative of amphetamine and ovalbumin were optimized. It was shown that the specificity of the proposed method when used in clinical conditions corresponds to that of gas chromatography with mass spectrometric detection. 相似文献
5.
M. A. Maslov N. G. Morozova T. V. Solomatina N. G. Shaforostova G. A. Serebrennikova 《Russian Journal of Bioorganic Chemistry》2011,37(4):507-515
Amino analogues of cholic acid were synthesized by reduction of oximes using titanium(III) chloride in the presence of sodium cyanoborohydride. 相似文献
6.
Dubinina EE Gavrovskaya SV Kuzmich EV Leonova NV Morozova MG Kovrugina SV Smirnova TA 《Biochemistry. Biokhimii?a》2002,67(3):343-350
Specific features of metal-catalyzed oxidation (MCO) of purified proteins (human serum albumin and human erythrocyte superoxide dismutase) were analyzed by the oxidation level of tryptophan and tyrosine. The production of dityrosine cross-links and the oxidation of tryptophan residues were recorded by fluorescence. The degree of oxidative modification of the amino acid residues of the proteins depended on the concentration of the Fenton's medium components and on the incubation time. These changes were different in different proteins. By electrophoresis and gel-permeation chromatography, changes in the superoxide dismutase structure are shown to be caused by oxidative modification of the enzyme and to be accompanied by a decrease in its activity. Findings with OH. scavengers (mannitol and ethanol) suggest that oxidative modification of the proteins in Fenton's medium should be associated not only with hydroxyl radical but also with ferryl and perferryl ions and with the radical PH3. 相似文献
7.
Levashov PA Popov DV Popova VM Zhilenkov EL Morozova OA Belogurova NG Sedov SA Dyatlov IA Klyachko NL Levashov AV 《Biochemistry. Biokhimii?a》2010,75(9):1160-1164
Bacteriophage enzyme preparations exolysin and endolysin were studied. Exolysin (a phage-associated enzyme) was obtained from
tail fraction and endolysin from phage-free cytoplasmic fraction of disintegrated Salmonella enteritidis cells. A new method for purification of these enzymes was developed, and their molecular masses were determined. The main
catalytic properties of the studied enzymes (pH optimum and specificity to bacterial substrates) were found to be similar.
Both enzymes lyse Escherichia coli cells like chicken egg lysozyme, but more efficiently lyse S. enteritidis cells and cannot lyse Micrococcus luteus, a good substrate for chicken egg lysozyme. Similar properties of exolysin and endolysin suggest that these enzymes are structurally
similar or even identical. 相似文献
8.
A major determinant of plant architecture is the arrangement of branches around the stem, known as phyllotaxis. However, the
specific form of branching conditions is not known. Here we discuss this question and suggest a branching model which seems
to be in agreement with biological observations.
Recently, a number of models connected with the genetic network or molecular biology regulation of the processes of pattern
formation appeared. Most of these models consider the plant hormone, auxin, transport and distribution in the apical meristem
as the main factors for pattern formation and phyllotaxis. However, all these models do not take into consideration the whole
plant morphogenesis, concentrating on the events in the shoot or root apex. On the other hand, other approaches for modeling
phyllotaxis, where the whole plant is considered, usually are mostly phenomenological, and due to it, do not describe the
details of plant growth and branching mechanism.
In this work, we develop a mathematical model and study pattern formation of the whole, though simplified, plant organism
where the main physiological factors of plant growth and development are taken into consideration. We model a growing plant
as a system of intervals, which we will consider as branches. We assume that the number and location of the branches are not
given a priori, but appear and grow according to certain rules, elucidated by the application of mathematical modeling.
Four variables are included in our model: concentrations of the plant hormones auxin and cytokinin, proliferation and growth
factor, and nutrients—we observe a wide variety of plant forms and study more specifically the involvement of each variable
in the branching process. Analysis of the numerical simulations shows that the process of pattern formation in plants depends
on the interaction of all these variables. While concentrations of auxin and cytokinin determine the appearance of a new bud,
its growth is determined by the concentrations of nutrients and proliferation factors. Possible mechanisms of apical domination
in the frame of our model are discussed. 相似文献
9.
Victoria?BrankinEmail author Marcus?RP?Mitchell Bob?Webb Morag?G?Hunter 《Reproductive biology and endocrinology : RB&E》2003,1(1):55
Oocyte control of granulosa and theca cell function may be mediated by several growth factors via a local feedback loop(s)
between these cell types. This study examined both the role of oocyte-secreted factors on granulosa and thecal cells, cultured
independently and in co-culture, and the effect of stem cell factor (SCF); a granulosa cell derived peptide that appears to
have multiple roles in follicle development. Granulosa and theca cells were isolated from 2–6 mm healthy follicles of mature
porcine ovaries and cultured under serum-free conditions, supplemented with: 100 ng/ml LR3 IGF-1, 10 ng/ml insulin, 100 ng/ml
testosterone, 0–10 ng/ml SCF, 1 ng/ml FSH (granulosa), 0.01 ng/ml LH (theca) or 1 ng/ml FSH and 0.01 ng/ml LH (co-culture)
and with/without oocyte conditioned medium (OCM) or 5 oocytes. Cells were cultured in 96 well plates for 144 h, after which
viable cell numbers were determined. Medium was replaced every 48 h and spent medium analysed for steroids. 相似文献
10.
RP Tucker K Drabikowski JF Hess J Ferralli R Chiquet-Ehrismann JC Adams 《BMC evolutionary biology》2006,6(1):60-17