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51.
Tretyakov Valentin F. Burdeynaya Tatyana N. Davydova Margarita N. Matyshak Valerii A. Glebov Leonid S. 《Topics in Catalysis》2001,16(1-4):243-245
The process of selective catalytic reduction of nitrogen oxides by propane in the presence of O2, as well as in the presence or absence of CO, was studied over series of commercial oxide catalysts used in petrochemical processes. For the first time synergistic effect was observed for catalytic systems consisting of mechanical mixtures of Cu–Zn–Ni–Al (catalyst I) + Fe–Cr (catalyst II) and Cu–Zn–Ni–Al (catalyst I) + Ni–Cr (catalyst III). The activity of these mixtures in nitrogen oxides reduction by propane was greater than that of individual components in each case. The worked-out catalytical systems showed high effectivity in the process of simultaneous removal of several toxic components: NO
x
, CO, hydrocarbons – from model gas mixtures, as well as from real exhausts of automotive transport. 相似文献
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Tatyana A. Vasilyeva Andrey V. Marakhonov Sergey I. Kutsev Rena A. Zinchenko 《International journal of molecular sciences》2022,23(12)
Genome-wide sequencing metadata allows researchers to infer bias in the relative frequencies of mutational events and to predict putative mutagenic models. In addition, much less data could be useful in the evaluation of the mutational frequency spectrum and the prevalent local mutagenic process. Here we analyzed the PAX6 gene locus for mutational spectra obtained in our own and previous studies and compared them with data on other genes as well as the whole human genome. MLPA and Sanger sequencing were used for mutation searching in a cohort of 199 index patients from Russia with aniridia and aniridia-related phenotypes. The relative frequencies of different categories of PAX6 mutations were consistent with those previously reported by other researchers. The ratio between substitutions, small indels, and chromosome deletions in the 11p13 locus was within the interval previously published for 20 disease associated genomic loci, but corresponded to a higher end due to very high frequencies of small indels and chromosome deletions. The ratio between substitutions, small indels, and chromosome deletions for disease associated genes, including the PAX6 gene as well as the share of PAX6 missense mutations, differed considerably from those typical for the whole genome. 相似文献
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Pavel P. Tregub Anton S. Averchuk Tatyana I. Baranich Maria V. Ryazanova Alla B. Salmina 《International journal of molecular sciences》2022,23(20)
There is growing evidence that the remodeling of cerebral microvessels plays an important role in plastic changes in the brain associated with development, experience, learning, and memory consolidation. At the same time, abnormal neoangiogenesis, and deregulated regulation of microvascular regression, or pruning, could contribute to the pathogenesis of neurodevelopmental diseases, stroke, and neurodegeneration. Aberrant remodeling of microvesselsis associated with blood–brain barrier breakdown, development of neuroinflammation, inadequate microcirculation in active brain regions, and leads to the dysfunction of the neurovascular unit and progressive neurological deficits. In this review, we summarize current data on the mechanisms of blood vessel regression and pruning in brain plasticity and in Alzheimer’s-type neurodegeneration. We discuss some novel approaches to modulating cerebral remodeling and preventing degeneration-coupled aberrant microvascular activity in chronic neurodegeneration. 相似文献
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Margarita Alfimova Nikolay Kondratyev Galina Korovaitseva Tatyana Lezheiko Victoria Plakunova Marina Gabaeva Vera Golimbet 《International journal of molecular sciences》2022,23(20)
As genetic and environmental influences on schizophrenia might converge on DNA methylation (DNAm) within loci which are both associated with the disease and implicated in response to environmental stress, we examined whether DNAm within CYP17A1, a hypothalamus–pituitary–adrenal axis gene which is situated within the schizophrenia risk locus 10q24.32, would mediate genetic and environmental effects on stress-related schizophrenia symptoms. DNAm within an exonic–intronic fragment of CYP17A1 was assessed in the blood of 66 schizophrenia patients and 63 controls using single-molecule real-time bisulfite sequencing. Additionally, the VNTR polymorphism of the AS3MT gene, a plausible causal variant within the 10q24.32 locus, was genotyped in extended patient and control samples (n = 700). The effects of local haplotype, VNTR and a polyenviromic risk score (PERS) on DNAm, episodic verbal memory, executive functions, depression, and suicidality of patients were assessed. Haplotype and PERS differentially influenced DNAm at four variably methylated sites identified within the fragment, with stochastic, additive, and allele-specific effects being found. An allele-specific DNAm at CpG-SNP rs3781286 mediated the relationship between the local haplotype and verbal fluency. Our findings do not confirm that the interrogated DNA fragment is a place where genetic and environmental risk factors converge to influence schizophrenia symptoms through DNAm. 相似文献
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Volodymyr V. Oberemok Refat Z. Useinov Oleksii A. Skorokhod Nikita V. Galchinsky Ilya A. Novikov Tatyana P. Makalish Ekaterina V. Yatskova Alexander K. Sharmagiy Ilya O. Golovkin Yuri I. Gninenko Yelizaveta V. Puzanova Oksana A. Andreeva Edie E. Alieva Emre Eken Kateryna V. Laikova Yuri V. Plugatar 《International journal of molecular sciences》2022,23(24)
Insects vastly outnumber us in terms of species and total biomass, and are among the most efficient and voracious consumers of plants on the planet. As a result, to preserve crops, one of the primary tasks in agriculture has always been the need to control and reduce the number of insect pests. The current use of chemical insecticides leads to the accumulation of xenobiotics in ecosystems and a decreased number of species in those ecosystems, including insects. Sustainable development of human society is impossible without useful insects, so the control of insect pests must be effective and selective at the same time. In this article, we show for the first time a natural way to regulate the number of insect pests based on the use of extracellular double-stranded DNA secreted by the plant Pittosporum tobira. Using a principle similar to one found in nature, we show that the topical application of artificially synthesized short antisense oligonucleotide insecticides (olinscides, DNA insecticides) is an effective and selective way to control the insect Coccus hesperidum. Using contact oligonucleotide insecticide Coccus-11 at a concentration of 100 ng/μL on C. hesperidum larvae resulted in a mortality of 95.59 ± 1.63% within 12 days. Green oligonucleotide insecticides, created by nature and later discovered by humans, demonstrate a new method to control insect pests that is beneficial and safe for macromolecular insect pest management. 相似文献