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81.
82.
Lilia Mourenets Alexander Pushin Vadim Timerbaev Tatyana Khmelnitskaya Eduard Gribkov Nikita Andreev Sergey Dolgov 《International journal of molecular sciences》2023,24(1)
Sharka disease, caused by the Plum pox virus (PPV), is one of the most harmful, quarantine viral diseases that affect stone fruit crops. The absence of natural resistance to the virus in stone fruits has become a decisive factor for the use of genetic transformation methods to obtain stable forms. The eIF(iso)4G and eIF(iso)4E genes encode translation initiation factors used in the PPV life cycle. In the presented study, the effect of silencing these genes using the RNA interference method on the resistance of sour cherry rootstock 146-2 plants (Prunus pumila L. x Prunus tomentosa Thunb) to the sharka disease was studied. Two vectors have been created for the genetic transformation of plants, with self-complementary sequences of the eIF(iso)4G and eIF(iso)4E gene fragments. The hairpin expression cassette contains a strong promoter of the peach ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCo) gene, as well as an intron and terminator of the same gene. We used the pMF1 vector containing recombinase R and a codA-nptII gene which makes it possible to obtain intragenic marker-free plants. A successful genetic transformation was carried out by the AGL0 strain of A. tumefaciens. Whole leaves of shoots cultivated in vitro were used as a source of explants. Eight independent transgenic lines of rootstock 146-2 were obtained in experiments (sixlines with a hairpin to the eIF(iso)4G gene and two lines with a hairpin to the eIF(iso)4E gene). Their status was confirmed by the PCR and Southern blotting. The obtained plants were acclimatized in a greenhouse. The silencing of the eIF(iso)4G and eIF(iso)4E genes in transgenic plants was confirmed by the quantitative PCR. The presence of specific small interfering (si) RNAs was confirmed by the method of Northern blotting. Plants of all transgenic rootstock lines were infected with PPV by the method of grafting with infected buds. Resistance to the PPV infection of the obtained transgenic plants was carried out by using an enzyme immunoassay. The ELISA results showed that silencing the eIF(iso)4G gene did not lead to increased resistance while silencing the eIF(iso)4E factor gene led to increased resistance to the PPV, and the one line’s plants showed no signs of infection for two years after infecting. The work demonstrates a (promising) approach in which the creation of stone cultures resistant to the plum pox virus can be achieved by suppressing the genes of translation initiation factors in clonal rootstocks. 相似文献
83.
Maxim V. Tarasov Olga D. Bochkova Tatyana V. Gryaznova Asiya R. Mustafina Yulia H. Budnikova 《International journal of molecular sciences》2023,24(1)
The present work describes an efficient reaction of electrochemical phosphorylation of phenylacetylene controlled by the composition of catalytic nanoparticles based on non-noble-metals. The sought-after products are produced via the simple synthetic protocol based on room temperature, atom-economical reactions, and silica nanoparticles (SNs) loaded by one or two d-metal ions as nanocatalysts. The redox and catalytic properties of SNs can be tuned with a range of parameters, such as compositions of the bimetallic systems, their preparation method, and morphology. Monometallic SNs give phosphorylated acetylene with retention of the triple bond, and bimetallic SNs give a bis-phosphorylation product. This is the first example of acetylene and phosphine oxide C-H/P-H coupling with a regenerable and recyclable catalyst. 相似文献
84.
Anton S. Rudovich Miroslav Peina Anastasiya V. Krech Maria Y. Novozhilova Anastasia M. Tumilovich Tatyana V. Shkel Irina P. Grabovec Miroslav Kvasnica Luk Mada Maria G. Zavialova Arif R. Mekhtiev Radek Jorda Vladimir N. Zhabinskii Vladimir A. Khripach 《International journal of molecular sciences》2022,23(21)
85.
86.
The sulfated polysaccharides from brown algae – the fucoidans – are known to be a topic of numerous studies, due to their beneficial biological activities including anti-tumour activity. In this study the effect of fucoidans isolated from brown algae Saccharina cichorioides, Fucus evanescens, and Undaria pinnatifida on the proliferation, neoplastic transformation, and colony formation of mouse epidermal cells JB6 Cl41, human colon cancer DLD-1, breast cancer T-47D, and melanoma RPMI-7951 cell lines was investigated. The algal fucoidans specifically and markedly suppressed the proliferation of human cancer cells with less cytotoxic effects against normal mouse epidermal cells. The highly sulfated (1 → 3)-α-l-fucan from S. cichorioides was found to be vitally important in the inhibition of EGF-induced neoplastic transformation of JB6 Cl41 cells. In colony formation assay the fucoidans from different species of brown algae showed selective anti-tumour activity against different types of cancer, which depended on unique structures of the investigated polysaccharides. These results provide evidence for further exploring the use of the fucoidans from S. cichorioides, F. evanescens, and U. pinnatifida as novel chemotherapeutics against different types of cancer. 相似文献
87.
Tatyana V. Laurinavichene Kestutis S. Laurinavichius Anatoly A. Tsygankov 《International Journal of Hydrogen Energy》2014
Purple non-sulfur bacteria Rhodobacter sphaeroides N7 was integrated into the heterotrophic starch-hydrolyzing consortium containing Clostridium butyricum as the main component. The resulting light-dependent consortium with Bchl ∼9 μg/ml was maintained during 12 months of regular transfers. The protein content in this consortium was four-fold higher compared to the heterotrophic consortium, suggesting that purple bacteria became its important component. Under illumination, the starch hydrolysis by the light-dependent consortium (as opposed to heterotrophic consortium) resulted in the absence of VFAs, hydrogen production being quite similar and residual hexose higher. Fermentation of glucose (unlike to starch) by the light-dependent consortium or Rb. sphaeroides alone resulted in ∼3 fold increase of hydrogen production compared to the heterotrophic consortium. Apparently, hydrolysis of starch to hexose was the bottleneck in H2 photoproduction by the light-dependent consortium. Availability of residual hexose after photofermentation of starch/glucose by the light-dependent consortium or Rb. sphaeroides is discussed. 相似文献
88.
Elena Burakova Tatyana Dyachkova Alexey Tkachev Evgeny Tugolukov Nariman Memetov Evgeny Galunin 《Fullerenes, Nanotubes and Carbon Nanostructures》2020,28(4):348-352
AbstractIn the present paper, the features of obtaining a metal oxide Fe–Co/Al2O3 catalyst for the synthesis of carbon nanostructured materials through thermal decomposition are considered. It was experimentally proved that the temperature and duration of the stage of thermal decomposition of the initial components solution significantly affect the catalyst activity in the synthesis of carbon nanostructured materials by the CVD method. It was found that controlling the mode parameters of the thermal decomposition of the initial components solution of the Fe–Co/Al2O3 catalyst, one can not only obtain a catalyst with the required characteristics but also directionally synthesize carbon nanostructured materials over the resulting catalytic systems. During the experiments, rational modes for the implementation of the method for producing catalysts were determined, allowing to form a metal oxide system with a specific surface area of 108?m2/g, the use of which in the synthesis of carbon nanostructured materials leads to the formation of multi-walled carbon nanotubes with an external diameter of 30?nm. 相似文献
89.
The Al ― Mg ― Si phase diagram was studied and the formation conditions for a regular two-phase eutectic structure (α-Al + Mg2Si) were established. Concentration limits were found for optimum alloy compositions with maximum melting point (~595°C) and a narrow (or zero) melting (crystallization) range (less than 5°C). The structures of these alloys are formed by Mg2Si monocrystal fibers and lamellae with a high degree of ordering, located in the aluminum matrix. 相似文献
90.
In a partial replication and extension of a survey conducted 25 years ago (Smith, 1982), over 2,400 North American psychotherapists completed a Web-based survey in which they identified prominent figures in the psychotherapy field who have most influenced their practice and the best psychotherapy books they had read in the past 3 years. There is a continued prominence to leaders of the field from 25 years ago but who are now deceased, notably the top-ranked Carl Rogers. Three books on the top-10 list represent empirically supported therapies (ESTs); two are treatment manuals for an EST, and one is a self-help book derived from an EST that has itself been shown to be efficacious bibliotherapy. Differences between psychologist and nonpsychologist therapists in the choice of influential figures, authors, and books are negligible. Implications are discussed in terms of the contemporary context into which therapeutic innovations are disseminated, as well as the conditions that may be necessary for successful dissemination. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献