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101.
102.
N V Popova V S Kesarev I I Poletaeva L G Romanova 《Zhurnal vysshe? nervno? deiatelnosti imeni I P Pavlova》1983,33(3):576-582
The cortex cytoarchitectonics was studied in mice, which had been genetically selected for high (H-line) and low (L-line) brain weight and manifested some differences in their behaviour. Microscopic brain sections were analysed to estimate the areas of the neocortex, archicortex and paleocortex and to investigate quantitatively the microstructure in different zones of the neocortex. In the H-line, absolute value of total cortical area is, on the average, by 18% higher than that in the L-line--mainly owing to the larger area of neocortex, while the mean values of neurone volume fraction and profile field reveal no significant difference between the H- and L-line. Hence, the total number of neurones in the neocortex of mice from H-line should be greater, as compared with the L-line. Besides, within the framework of the same cerebral organization in general, the obtained data are indicative of a somewhat higher spatial differentiation of the neocortex in mice from the H-line. 相似文献
103.
The effects of sodium hydroxybutyrate and piracetam on compensatory-reparative processes in the central nervous system have been investigated in rats after extirpation of the frontal cortex. The animals were pretrained to conditioned reflex of active avoidance. Extirpation of the frontal cortex has been shown to disturb the conditioned reflex. Sodium hydroxybutyrate (50 mg/kg) and piracetam (200 mg/kg) were found to precipitate the recovery of the damaged reflexes. 相似文献
104.
L G Gorina R Iu Romanova S A Goncharova 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》1986,(4):18-21
In the peripheral blood of patients with chronic bronchitis the presence of Mycobacterium pneumoniae antigens has been registered in 20.0% of cases and the presence of group A Streptococcus haemolyticus antigens, in 24.0% of cases, the transformation of streptococci into the L-form being observed in 12.0% of cases. The presence of M. pneumoniae, streptococci and their L-forms, as well as associations of these microorganisms, is characteristic of patients with chronic obstructive bronchitis, which is, probably, one of the reasons for the maintenance of bronchial obstruction. In patients with chronic pneumonia and fibrosing alveolitis the antigens of the bacterial form of streptococcus and its L-forms have been detected only in a few cases. 相似文献
105.
106.
Aver’yanov A. A. Pasechnik T. D. Lapikova V. P. Romanova T. S. Babosha A. V. Baker C. J. 《Russian Journal of Plant Physiology》2019,66(6):932-941
Russian Journal of Plant Physiology - The study is aimed at the induction of systemic disease resistance by a local oxidative burst caused by inhibition of plant antioxidant enzymes. A possible... 相似文献
107.
Monakhova M. V. Kubareva E. A. Romanova E. A. Semkina A. S. Naberezhnov D. S. Rao D. N. Zatsepin T. S. Oretskaya T. S. 《Russian Journal of Bioorganic Chemistry》2019,45(2):144-154
Russian Journal of Bioorganic Chemistry - Diketone DNA derivatives have been proposed to modify the guanidine group of Arg in proteins. The β-diketo group at the C2' atom of the sugar... 相似文献
108.
Il'ina TS Romanova IuM Gintsburg AL 《Molekuliarnaia genetika, mikrobiologiia i virusologiia》2006,(3):22-29
A review of the literature about the bacterial systems of regulation of expression of the genes controlled by signals generated by the bacteria themselves is given. Three types of presently known Quorum sensing systems contributing to the expression of the pathogenicity factors, infection process, and formation of biofilms by pathogenic bacteria are described. Possible mechanisms of enhanced resistance of bacteria in films to antibacterial preparations and factors of immune protection of human body are discussed. The perspectives of the development of new approaches to treatment of chronic diseases caused by the pathogens producing bacterial films are considered. 相似文献
109.
Bakhteeva VT Fok EM Lavrova EA Gorbushin AM Romanova IV Nikolaeva SD Parnova RG 《Rossi?skii fiziologicheski? zhurnal imeni I.M. Sechenova / Rossi?skaia akademiia nauk》2006,92(8):1022-1028
In experiments on frog Rana temporaria L. urinary bladder, we investigated localization of NO-synthase (NOS) in urinary bladder slices and measured NOS activity in the suspension of mucosal epithelial cells. Intensive NADPH-diaphorase staining which is widely used as an indicator of NOS activity was found in mucosal epithelium. Almost all mucosal epithelial cells isolated in Ca2+ -free conditions demonstrated positive NADPH-diaphorase reactivity. Direct measurement of NOS activity in suspension of mucosal cells determined by the rate of conversion of L-arginine to L-citrullin showed that the enzyme activity was reduced in absence of external Ca2+ and was inhibited by L-NAME: non-specific NOS inhibitor, and 1400 W: a highly selective iNOS inhibitor (control: 754 +/- 184; L-NAME, 1 mM 329 +/- 87; 1400 W, 20 mM: 547 +/- 25; Ca2+ -free/EDTA: 490 +/- 184 cpm [3H]-citrullin/10(6) cells per 45 min, p < 0.05, n = 7-8). The data obtained demonstrate that frog urinary bladder mucosa epithelial cells provided antidiuretic hormone-induced increase of osmotic water permeability contain nitric oxide synthase. The presence of inducible (iNOS) as well as constitutive isoform(s) revealed in these cells allows to suggest involvement of NOS in intracellular signaling pathways regulated water transport across the epithelium. 相似文献
110.
Liudmila Romanova Anthony Grand Liying Zhang Samuel Rayner Nobuko Katoku-Kikyo Steven Kellner Nobuaki Kikyo 《The Journal of biological chemistry》2009,284(8):4968-4977
Nucleostemin is a nucleolar protein widely expressed in proliferating
cells. Nucleostemin is involved in the regulation of cell proliferation, and
both depletion and overexpression of nucleostemin induce cell cycle arrest
through the p53 signaling pathway. Although the presence of p53-independent
functions of nucleostemin has been previously suggested, the identities of
these additional functions remained to be investigated. Here, we show that
nucleostemin has a novel role as an integrated component of ribosome
biogenesis, particularly pre-rRNA processing. Nucleostemin forms a large
protein complex (>700 kDa) that co-fractionates with the pre-60 S ribosomal
subunit in a sucrose gradient. This complex contains proteins related to
pre-rRNA processing, such as Pes1, DDX21, and EBP2, in addition to several
ribosomal proteins. We show that the nucleolar retention of DDX21 and EBP2 is
dependent on the presence of nucleostemin in the nucleolus. Furthermore, the
knockdown of nucleostemin delays the processing of 32 S pre-rRNA into 28 S
rRNA. This is accompanied by a substantial decrease of protein synthesis as
well as the levels of rRNAs and some mRNAs. In addition, overexpressed
nucleostemin significantly promotes the processing of 32 S pre-rRNA.
Collectively, these biochemical and functional studies demonstrate a novel
role of nucleostemin in ribosome biogenesis. This is a key aspect of the role
of nucleostemin in regulating cell proliferation.Nucleostemin (NS)2
is a nucleolar protein preferentially expressed in actively proliferating
cells. The structure of NS is characterized by two GTP-binding domains, which
are involved in the regulation of its dynamic shuttling between the nucleolus
and nucleoplasm (1). NS was
originally identified as a nucleolar protein prominently expressed in rat
neural stem cells and down-regulated during differentiation of these cells
in vitro (2). The same
authors also found that NS is widely expressed in neural precursor cells in
early mouse embryos as well as in a variety of cancer cells and stem cells,
including embryonic stem cells and a hematopoietic stem cell-enriched
fraction. NS is generally down-regulated in the early stage of differentiation
before exit from the cell cycle. In addition, knockdown of NS significantly
inhibits proliferation of cortical stem cells and cancer cells. These initial
observations led to suggestions that NS is involved in multipotency in stem
cells as well as in the regulation of cancer and stem cell proliferation
(2).Recent work, however, has demonstrated that NS is in fact widely expressed
in many types of normal proliferating cells at levels similar to those in
malignant cells. For instance, NS is expressed in normal kidney cells and
renal carcinoma cells at comparable levels as detected in histological
sections (3). The expression of
NS is significantly up-regulated when normal T lymphocytes are activated by
concanavalin A (3) and when
bone marrow stem cells are stimulated by fibroblast growth factor 2
(4). Cells in NS-null mouse
embryos fail to enter the S phase, resulting in embryonic death at the
blastocyst stage (5,
6). In early Xenopus
embryos NS is also expressed in the sites of active cell proliferation and
local depletion of NS results in a decrease in proliferating neural progenitor
cells (6). Based on these
observations, it was proposed that expression of NS is more closely linked
with cell proliferation than with the malignant state or differentiation
status of a cell.Several studies have provided evidence that the p53 signaling pathway is
involved in the G1 arrest of the cell cycle induced by the
down-regulation of NS. Physical interaction between NS and p53 was initially
reported by Tsai and McKay (2).
Later, it was shown that the G1 arrest requires the presence of p53
(7). In the most recent study
Dai et al. (8) showed
that knockdown of NS enhances the interaction between the p53-binding protein
MDM2 and the ribosomal protein L5 or L11, preventing MDM2 from inducing
ubiquitylation-based p53 degradation. However, other studies have also
suggested that NS may have a p53-independent role in the regulation of cell
proliferation. For instance, the depletion of p53 from NS-null blastocysts did
not rescue them from the embryonic lethality
(6). In addition, NS partial
loss-of-function in mouse fibroblasts did not result in any change in the p53
level (5). Furthermore,
knockdown of L5 and L11 only partially rescued the G1 arrest in NS
knockdown cells (8). Finally,
the fact that NS is primarily localized in the nucleolus, whereas the
p53-mediated mechanism occurs in the nucleoplasm, suggests that NS might have
an additional role more directly relevant to nucleolar functions.To identify novel functions of NS, we purified an endogenous NS complex
from HeLa cell extract and investigated whether NS interacts with other
proteins not described previously. Identification of the components of this
complex and the alterations of the expression level of NS in HeLa cells led us
to uncover a novel role of NS in the processing of rRNA. Our findings not only
provide supporting evidence for the hypothesis that NS has a p53-independent
function but also demonstrate that NS is critical for ribosome biogenesis, one
of the most fundamental processes common for all cell types. 相似文献