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51.
The Y-box binding protein 1 (YB-1) is a member of the family of DNA- and RNA binding proteins. It is involved in a wide variety of DNA/RNA-dependent events including cell proliferation and differentiation, stress response, and malignant cell transformation. Previously, YB-1 was detected in neurons of the neocortex and hippocampus, but its precise role in the brain remains undefined. Here we show that subchronic intranasal injections of recombinant YB-1, as well as its fragment YB-11−219, suppress impairment of spatial memory in olfactory bulbectomized (OBX) mice with Alzheimer’s type degeneration and improve learning in transgenic 5XFAD mice used as a model of cerebral amyloidosis. YB-1-treated OBX and 5XFAD mice showed a decreased level of brain β-amyloid. In OBX animals, an improved morphological state of neurons was revealed in the neocortex and hippocampus; in 5XFAD mice, a delay in amyloid plaque progression was observed. Intranasally administered YB-1 penetrated into the brain and could enter neurons. In vitro co-incubation of YB-1 with monomeric β-amyloid (1–42) inhibited formation of β-amyloid fibrils, as confirmed by electron microscopy. This suggests that YB-1 interaction with β-amyloid prevents formation of filaments that are responsible for neurotoxicity and neuronal death. Our data are the first evidence for a potential therapeutic benefit of YB-1 for treatment of Alzheimer’s disease.  相似文献   
52.
Russian Journal of Bioorganic Chemistry - The membrane receptor for advanced glycation endproducts (RAGE) is involved in the development of a number of pathological conditions, including...  相似文献   
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54.
Health status of trees was studied in five types of native spruce forests in the Pechora-Ilych Nature Biosphere Reserve. The study has shown that trees in the old-growth bilberry-spruce and fern-shamrock-spruce forests can be characterized as “healthy”, with damage index varying from 0.03 to 0.5. The haircap-moss spruce forest with damage index 0.7 is categorized as a “weakened stand”. Regeneration was pronounced in all forest types. Young growth (1500 to 4300 stems/ha) is mainly composed of conifers and is classified as “healthy”.  相似文献   
55.
For 6 months the rats were kept on 20 degrees ethanol. Then, the rats could choose whether to drink alcohol (A) or water. The rats formed 2 groups: those preferring A and those preferring water. The control rats were kept on water. The function of hypothalamus monoamine- and peptidergic systems were disturbed following chronic A treatment. Alcohol-preferring, unlike water-preferring rats, have revealed higher hypothalamus levels of serotonin and lower levels of dopamine and noradrenaline, which correlated with changes in fluorescence intensity of hypothalamus noradrenaline structures and were accompanied by remarkable disturbances in nonapeptide neurohormone transport in the paraventricular nucleus region.  相似文献   
56.
Separation of alpha- and beta-subunits of phenylalanyl-tRNA-synthetases from E. coli MRE-600 and Thermus thermophilus HB8 using FPLC has been carried out for the first time. The separated subunits of both enzymes do not possess any detectable tRNA-amino-acylation activity. It was found that in the case of the E. coli enzyme beta-subunits exist in solution mainly in the monomeric form with negligible formation of beta 2-dimers, while alpha-subunits predominantly form alpha 2-dimers over the same concentration range. In the case of Thermus thermophilus phenylalanyl-tRNA-synthetase, both alpha- and beta-subunits mainly exist in the dimeric form. The putative mechanisms of alpha-subunit aggregation and of subunit association for alpha 2 beta 2-type enzymes are discussed.  相似文献   
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Ctenophores are one of the most basally branching lineages of metazoans with the largest mitochondrial organelles in the animal kingdom. We sequenced the mitochondrial (mtDNA) genome from the Pacific cidipid ctenophore, Pleurobrachia bachei. The circular mitochondrial genome is 11,016 nts, with only 12 genes, and one of the smallest metazoan mtDNA genomes recorded. The protein coding genes are intronless cox1-3, cob, nad1, 3, 4, 4L and 5. The nad2 and 6 genes are represented as short fragments whereas the atp6 gene was found in the nuclear genome. Only the large ribosomal RNA subunit and two tRNAs were present with possibly the small subunit unidentifiable due to extensive fragmentation. The observed unique features of this mitochondrial genome suggest that nuclear and mitochondrial genomes have evolved at very different rates. This reduced mtDNA genome sharply contrasts with the very large sizes of mtDNA found in other basal metazoans including Porifera (sponges), and Placozoa (Trichoplax).  相似文献   
59.
The study of glutathione in the blood plasma of NMR1 mice during the development of a pathology that simulates neurodegeneration caused by removal of the olfactory bulbs (bulbectomy) was carried out in comparison with sham-operated (not subjected to the removal of the olfactory bulbs) and control (before surgery) animals. At 1 month after surgery, a twofold increase in the levels of reduced and oxidized glutathione was detected and an increase in the thiol/disulfide ratio in the blood plasma of bulbectomized mice relative to sham-operated animals was observed. A decrease in the thiol/disulfide ratio as a result of depletion of reduced glutathione and accumulation of oxidized glutathione in animal blood plasma was observed during the period from 3 to 12 months, which is a sign of a pathological process. The major disorders related to oxidative stress were revealed during the maximum manifestation of the disease. During this period, a significant decrease in the reducing capacity of cellular redox pairs, such as reduced glutathione/glutathione disulphide was observed.  相似文献   
60.
Abstract. Among malacostracan crustaceans, intracerebral ocelli were first discovered in Isopoda, but they have been more recently reported from a crayfish ( Cherax destructor ) and a sandhopper ( Talitrus saltator ). This electron microscopic study increases the number of crayfish taxa in which intracerebral ocelli are now known to occur by two: Astacidae and Cambaridae. These photoreceptors are always integrated into the anteromedio-dorsal part of the brain and are not visible externally. Each ocellus is made up of 4–5 photoreceptor cells and is characterized by the presence of a fused rhabdom. The occurrence of different kinds of lysosomes in the cytoplasm is indicative of metabolic activity and perhaps membrane turnover. One typical feature of crayfish ocelli is their extraordinary variability in number. This trait is exemplified by individuals of Pacifastacus leniusculus , where as many as 14 ocelli were identified in a single brain. The arrangement of the ocelli is often not symmetrical with regard to the brain's midline and the ocelli always lack dioptric structures. Thus, it is difficult to see how they are involved in image formation. However, further research is needed to determine the precise role of these "hidden" receptors.  相似文献   
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