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41.
A. M. Derbentseva A. A. Cherentsova L. P. Mayorova T. I. Matveenko E. A. Popova A. V. Brikmans 《Contemporary Problems of Ecology》2016,9(5):652-661
The ecological state of soils as a component of technogenic and industrial systems has been characterized in the impact zone of mine terricones of empty coal-mining rocks. The results of analytical works showed the regional features of lithostrats and soils: the increased total content of hexavalent chromium (700 maximum permissible concentration (MPC) or more) and trivalent iron (18000 mg/kg or more). This is due to the relationship between the geochemical background of the area and natural technogenic factors under the conditions of monsoon climate promoting acidogenesis development. 相似文献
42.
Belokopytova Irina I. Kondaurova Elena M. Kulikova Elizabeth A. Ilchibaeva Tatiana V. Naumenko Vladimir S. Popova Nina K. 《Biochemistry. Biokhimii?a》2022,87(10):1206-1218
Biochemistry (Moscow) - The mechanisms of autism are of extreme interest due to the high prevalence of this disorder in the human population. In this regard, special attention is given to the... 相似文献
43.
Prabakaran Nagarajan Paula A. Agudelo Garcia Chitra C. Iyer Liudmila V. Popova William D. Arnold Mark R. Parthun 《Aging cell》2019,18(5)
Histone acetyltransferase 1 (Hat1) is responsible for the acetylation of newly synthesized histone H4 on lysines 5 and 12 during the process of chromatin assembly. To understand the broader biological role of Hat1, we have generated a conditional mouse knockout model of this enzyme. We previously reported that Hat1 is required for viability and important for mammalian development and genome stability. In this study, we show that haploinsufficiency of Hat1 results in a significant decrease in lifespan. Defects observed in Hat1+/? mice are consistent with an early‐onset aging phenotype. These include lordokyphosis (hunchback), muscle atrophy, minor growth retardation, reduced subcutaneous fat, cancer, and paralysis. In addition, the expression of Hat1 is linked to the normal aging process as Hat1 mRNA and protein becomes undetectable in many tissues in old mice. At the cellular level, fibroblasts from Hat1 haploinsufficient embryos undergo early senescence and accumulate high levels of p21. Hat1+/? mouse embryonic fibroblasts (MEFs) display modest increases in endogenous DNA damage but have significantly higher levels of reactive oxygen species (ROS). Consistently, further studies show that Hat1?/? MEFs exhibit mitochondrial defects suggesting a critical role for Hat1 in mitochondrial function. Taken together, these data show that loss of Hat1 induces multiple hallmarks of early‐onset aging. 相似文献
44.
45.
Transcriptome‐based phylogeny of endemic Lake Baikal amphipod species flock: fast speciation accompanied by frequent episodes of positive selection 下载免费PDF全文
46.
R Jablenska P Popova G Guencheva J Duhault M Lesourd P Petkov 《Cellular and molecular biology, including cyto-enzymology》1991,37(6):575-583
The effect of neurotropin (NSP) in combination with streptozotocin (STZ) and cyclophosphamide (CY) on blood glucose and pancreatic histopathology on day 7 and day 14 after the initiation of the treatment was studied in C57Bl/6 male mice. STZ (40 mg/kg) and NSP (1 mg/kg) were applied intraperitoneally on five consecutive days and CY (150 mg/kg)--twice on day 1 and day 3. In single B cells dilatation of the endoplasmic reticulum was found. On day 7 in proximity to some endocrine cells in the mice treated with STZ, STZ + CY + NSP and STZ + CY macrophages were observed. On day 14 lymphocytic infiltration of the islets was demonstrated only in the groups of mice injected with STZ, STZ + CY while in the group treated with the combination STZ + CY + NSP no infiltration was seen. All experimental groups showed no biochemical evidence for hyperglycemia probably due to the mild destruction of a small number of B cells. The results indicate that NSP might possess a restorative action on insulitis induced by multiple low dose streptozotocin administration in mice. 相似文献
47.
Inactivation of the nitrate-reducing system in whole cells of Chlorella vulgaris Bejerinck by darkening, nitrogen starvation, ammonium, or cycloheximide brings cells into a state with a high yield of the millisecond-delayed fluorescence of chlorophyll. Activation of this system by illumination, by adding glucose to dark-adapted cells or nitrate to nitrogen-starved cells brings the cells into a low-yield state. The transitions between the lowand high-yield state induced by alternating light and dark periods are suppressed by tungstate and restored by subsequent molybdate addition. The drop in the delayed-fluorescence yield upon activation of the nitrate-reducing system is associated with the decrease of the amplitude of the electrochemical proton gradient across the thylakoid membrane of the chloroplast, as evidenced by the kinetics of the light-induced adsorption changes at 520 nm. The decrease of the proton gradient may be caused by the electron flow diverting from the cyclic path in photosystem I as a result of the activation of the electron transfer from ferredoxin to nitrite.Abbreviation DCMU
3-(3,4-dichlorophenyl)-1,1-dimethylurea 相似文献
48.
Yu. I. Arshavskii E. S. Meizerov G. N. Orlovskii G. A. Pavlova L. B. Popova 《Neurophysiology》1985,17(3):226-231
Activity of propriospinal neurons in segments C3 and C4 was recorded in immobilized decerebrate cats, whose spinal cord was divided at the lower thoracic level, during locomotor activity of neuronal mechanisms controlling the forelimbs (fictitious locomotion of the forelimbs). Neurons were identified according to antidromic responses to stimulation of the lateral column of the spinal cord at level C6. Antidromic responses also appeared in 70% of these neurons to stimulation of the medullary lateral reticular nucleus. During fictitious locomotion, i.e., in the absence of afferent signals from the limb receptors, rhythmic modulation of the discharge of most neurons was observed, correlating with activity of motoneurons. If the rostral region of the cervical enlargement of the spinal cord was cooled, causing generation of the locomotor rhythm to cease, rhythmic activity of propriospinal neurons in segments C3 and C4 also ceased. The main source of modulation of activity of propriospinal neurons in segments C3 and C4 is thus the central spinal mechanisms controlling activity of the forelimbs.Institute for Problems in Information Transmission, Academy of Sciences of the USSR, Moscow. M. V. Lomonosov Moscow University. Translated from Neirofiziologiya, Vol. 17, No. 3, pp. 320–326, May–June, 1985. 相似文献
49.
Malgorzata M. Barczyk Ning Lu Svetlana N. Popova Anne Isine Bolstad Donald Gullberg 《Journal of cellular physiology》2013,228(5):1108-1119
We have previously determined that integrin α11β1 is required on mouse periodontal ligament (PDL) fibroblasts to generate the force needed for incisor eruption. As part of the phenotype of α11?/? mice, the incisor PDL (iPDL) is thickened, due to disturbed matrix remodeling. To determine the molecular mechanism behind the disturbed matrix dynamics in the PDL we crossed α11?/? mice with the Immortomouse and isolated immortalized iPDL cells. Microarray analysis of iPDL cells cultured inside a 3D collagen gel demonstrated downregulated expression of a number of genes in α11‐deficient iPDL cells, including matrix metalloproteinase‐13 (MMP‐13) and cathepsin K. α11?/? iPDL cells in vitro displayed disturbed interactions with collagen I during contraction of attached and floating collagen lattices and furthermore displayed reduced MMP‐13 protein expression levels. The MMP‐13 specific inhibitor WAY 170523 and the Cathepsin K Inhibitor II both blocked part of the α11 integrin‐mediated collagen remodeling. In summary, our data demonstrate that in iPDL fibroblasts the mechanical strain generated by α11β1 integrin regulates molecules involved in collagen matrix dynamics. The positive regulation of α11β1‐dependent matrix remodeling, involving MMP‐13 and cathepsin K, might also occur in other types of fibroblasts and be an important regulatory mechanism for coordinated extracellular and intracellular collagen turnover in tissue homeostasis. J. Cell. Physiol. © 2012 Wiley Periodicals, Inc. 相似文献
50.
N. A. Sinyakova E. M. Kondaurova A. V. Kulikov V. S. Naumenko M. A. Tikhonova N. K. Popova 《Molecular Biology》2013,47(3):411-418
The glycoprotein gp130 mediates intracellular transduction of signal from receptors of cytokines belonging to the interleukin-6 group. The linkage of the Il6st gene encoding the gp130 protein to heritable predisposition to hypertrophic freezing reaction (catalepsy) has been demonstrated previously in mice. The aim of the present work was to investigate the levels of Il6st mRNA, as well as the distribution of the gp130 protein and the degree of its glycosylation, in five brain regions of mice of the non-cataleptic AKR/J line and the cataleptic lines CBA/LacJ and congenic line AKR.CBA-D13Mit76, which carries the CBA variant of the Il6st gene in the AKR/J genome. These parameters were also studied in mice of the ASC line obtained by backcrossing CBA and AKR mice with the simultaneous selection for the high predisposition to catalepsy. Maximum levels of unglycosylated and glycosylated forms of the gp130 protein were detected in the midbrains of mice from all investigated lines. The highest levels of Il6st mRNA were found in the midbrain, striatum, and hypothalamus of mice of all lines. The level of Il6st mRNA in the striatum of AKR.CBA-D13Mit76 mice was higher than in the striatum of AKR/J mice. Therefore, one can assume that there is a connection between heritable catalepsy and the increased expression of the Il6st gene in the striatum. 相似文献