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41.
42.
M P Filatova N A Krit O M Komarova V N Orekhovich S Reissmann 《Bioorganicheskaia khimiia》1986,12(1):59-70
To investigate conformations of peptide inhibitors of the angiotensin-converting enzyme in the enzyme-inhibitor complex, the synthesis, studies of inhibitory activity, and conformational calculations of analogues of bradykinin-potentiating peptides with N-methylalanine or D-alanine in place of L-proline or L-alanine residues have been carried out. All the analogues showed a sharp decrease of inhibitory activity in comparison with the natural peptides, that might be considered as an indirect confirmation of the earlier proposed "conformation of inhibition" of the above-mentioned peptides. 相似文献
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Killer whale discrete calls include types containing an overlapping high-frequency component (biphonic calls) and types without
an overlapping high-frequency component (monophonic calls). In the resident killer whales of the Northeast Pacific, biphonic
discrete calls exhibit higher source levels than monophonic calls, which suggests different active space and consequently
different functions for monophonic and biphonic call types. In this study we investigate the potential communicative functions
of monophonic and biphonic discrete calls produced by killer whales from Kamchatka (Northwest Pacific). We analyze how the
usage of these calls depends on the number of pods present in the area and type of activity. Our results show that the usage
of monophonic and biphonic calls in Kamchatkan killer whales depends on the number of pods in the area and is less dependent
on the type of activity. Biphonic calls are more common when more than one pod is present in the area and could therefore
function as markers of pod and matriline affiliation, serving mainly as cohesion signals. Monophonic calls dominated the vocalizations
when a single pod was present, while in the presence of more than one pod both categories were used in equal proportions. 相似文献
46.
The present work focused on the role of cholesterol-rich membrane microdomains (rafts) in cellular mechanisms of innate immunity and anticancer defence. The lytic effect of natural killers (NK) was examined in dependence on cholesterol content in transformed target cells. In the current study, K562 human erythroleukaemia cells were the targets. K562 cells were treated with methyl-beta-cyclodextrin (MbCD) to deplete membrane cholesterol that was verified by enzymatic method. With the use of 3H-uridine test, NK (mouse splenocytes) cytotoxity was estimated under various conditions, specifically, after incubation of K562 cells with MbCD or inactive analog alpha-cyclodextrin. The data obtained show that cholesterol-depleting treatment (2.5 or 5 mM MbCD) of target cells results in full loss of their sensitivity to NK lysis. The effect is likely to be due to disintegrity of lipid rafts that is critically dependent on the level of membrane cholesterol. Visualization of cell surface changes by fluorescent labeling of ganglioside GM1 confirmed our conclusions. 相似文献
47.
V. L. Myshkina E. A. Ivanov D. A. Nikolaeva T. K. Makhina A. P. Bonartsev E. V. Filatova A. O. Ruzhitsky G. A. Bonartseva 《Applied Biochemistry and Microbiology》2010,46(3):289-296
The ability of Azotobacter chroococcum strain 7B, producer of poly(3-hydroxybutyrate) (PHB), to synthesize its copolymer poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (P(3HB-co-3HV)) was studied. It was demonstrated, for the first time, that A. chroococcum strain 7B was able to synthesize P(3HB-co-3HV) with various molar rates of HV in the polymer chain when cultivated on medium with sucrose and carboxylic acids as precursors of HV elements in the PHB
chain, namely, valeric (13.1–21.6 mol %), propanoic (3.1 mol %), and hexanoic (2.1 mol %) acids. Qualitative and functional
differences between PHB and P(3HB-co-3HV) were demonstrated by example of the release kinetic of methyl red from films made
of synthesized polymers. Maximal HV incorporation into the polymer chain (28.8mol %) was recorded when the nutrient medium
was supplemented with 0.1% peptone on the background of 20 mM valerate. These results suggest that that the studied strain
can be regarded as a potential producer of not only PHB but also P(3HB-co-3HV). 相似文献
48.
E. V. Akhidova T. D. Volkova D. O. Koroev Ya. S. Kim M. P. Filatova N. M. Vladimirova T. A. Karmakova L. E. Zavalishina Yu. Yu. Andreeva O. M. Volpina 《Russian Journal of Bioorganic Chemistry》2010,36(2):164-171
Survivin, an endogenous protein, is a promising marker for the cancer diagnosis. The aim of the present work was to obtain
antibodies specific to survivin and capable of detecting this protein in tumor tissues. Four peptides corresponding to fragments
(1–22), (54–74), (80–88)–(153–165), and (118–144) of the survivin-2B sequence were selected and synthesized. Rabbits were
immunized with the synthetic peptides. It has been shown that all peptides in a free state, without conjugation with a high-molecular-weight
carrier, stimulate the production of antibodies capable of binding with recombinant survivin. Antipeptide antibodies were
isolated from sera and their performance in the immunohistochemical detection of survivin in human tumor tissues was studied.
It was shown that only antibodies to the (80–88)–(153–165) peptide bind to the survivin present in breast and bladder tumors.
The ability of antibodies to this peptide to detect survivin in tumor tissue lysates was demonstrated by immunoblotting. The
part of the sequence targeted by the antibodies against the (80–88)–(153–165) peptide was localized using truncated peptide
fragments. 相似文献
49.
Filatova OV Kiselev VD Trebukhov AV Kozlova LG 《Rossi?skii fiziologicheski? zhurnal imeni I.M. Sechenova / Rossi?skaia akademiia nauk》1999,85(12):1503-1511
In anaesthetised rabbits, femoral artery manifested a maximal reserve capacity in its vasodilatory response to the flow speed acceleration. In order of the capacity diminishing, this artery is followed by renal artery, abdominal aorta, celiacus tube, common carotid artery. The endothelium-dependent flow-induced response is important for restricting the flow's linear speed. 相似文献
50.
New fluorescent bichromophoric probes for studying mechanisms of donor-donor energy migration (DDEM)
Three fluorescent probes were synthesized for studying the excitation energy migration between two identical fluorophores. Each probe has two identical fluorescent groups (dansyl, 7-nitrobenz-2-oxa-1,3-diazole-4-yl, or fluoresceinyl) linked by the rigid bis-(8-aminooctyl)amide of 4,4'-biphenyldicarbonic acid or flexible dotriacontanedioic acid spacer, which enables the intramolecular energy migration through the distance of 3.2-3.5 nm. 相似文献