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排序方式: 共有802条查询结果,搜索用时 109 毫秒
1.
Mri Miczi Mria Golda Balzs Kunkli Tibor Nagy Jzsef Tzsr Jnos Andrs Mtyn 《International journal of molecular sciences》2020,21(24)
The novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the causative agent of coronavirus disease-19 (COVID-19) being associated with severe pneumonia. Like with other viruses, the interaction of SARS-CoV-2 with host cell proteins is necessary for successful replication, and cleavage of cellular targets by the viral protease also may contribute to the pathogenesis, but knowledge about the human proteins that are processed by the main protease (3CLpro) of SARS-CoV-2 is still limited. We tested the prediction potentials of two different in silico methods for the identification of SARS-CoV-2 3CLpro cleavage sites in human proteins. Short stretches of homologous host-pathogen protein sequences (SSHHPS) that are present in SARS-CoV-2 polyprotein and human proteins were identified using BLAST analysis, and the NetCorona 1.0 webserver was used to successfully predict cleavage sites, although this method was primarily developed for SARS-CoV. Human C-terminal-binding protein 1 (CTBP1) was found to be cleaved in vitro by SARS-CoV-2 3CLpro, the existence of the cleavage site was proved experimentally by using a His6-MBP-mEYFP recombinant substrate containing the predicted target sequence. Our results highlight both potentials and limitations of the tested algorithms. The identification of candidate host substrates of 3CLpro may help better develop an understanding of the molecular mechanisms behind the replication and pathogenesis of SARS-CoV-2. 相似文献
2.
Pavel Strunz Debashis Mukherji Přemysl Beran Ralph Gilles Lukas Karge Michael Hofmann Markus Hoelzel Joachim Rösler Gergely Farkas 《Metals and Materials International》2018,24(5):934-944
An addition of boron largely increases the ductility in polycrystalline high-temperature Co–Re alloys. Therefore, the effect of boron on the alloy structural characteristics is of high importance for the stability of the matrix at operational temperatures. Volume fractions of ε (hexagonal close-packed—hcp), γ (face-centered cubic—fcc) and σ (Cr2Re3 type) phases were measured at ambient and high temperatures (up to 1500 °C) for a boron-containing Co–17Re–23Cr alloy using neutron diffraction. The matrix phase undergoes an allotropic transformation from ε to γ structure at high temperatures, similar to pure cobalt and to the previously investigated, more complex Co–17Re–23Cr–1.2Ta–2.6C alloy. It was determined in this study that the transformation temperature depends on the boron content (0–1000 wt. ppm). Nevertheless, the transformation temperature did not change monotonically with the increase in the boron content but reached a minimum at approximately 200 ppm of boron. A probable reason is the interplay between the amount of boron in the matrix and the amount of σ phase, which binds hcp-stabilizing elements (Cr and Re). Moreover, borides were identified in alloys with high boron content. 相似文献
3.
4.
The atomistic structure and energies of high-index interphase boundaries are explored using a combination of molecular statics
and dynamics simulations with embedded atom potentials. We investigate planar boundaries between the α2 and γ phases in the Ti−Al system. The class of boundaries considered has a high-index boundary orientation; the orientation
relationship between the α2 and γ phases also is high index, and a set of planes from each phase meet edge to edge at the boundary plane. For the particular
case of a boundary that is commensurate in one direction and coincides with a moiré plane given by the so-called “Δg” diffraction condition, the boundary is not structurally singular, but it is energetically stable and does not appear to
dissociate into other low-energy configurations. Misfit compensating defects are not observed; misfit in directions other
than the commensurate one appears to be distributed uniformly. The boundary energy is evaluated as a function of the orientation
of the boundary plane, and the edge-to-edge (moiré) boundary is found to lie in an energy cusp.
This article is based on a presentation made in the “Hume-Rothery Symposium on Structure and Diffusional Growth Mechanisms
of Irrational Interphase Boundaries,” which occurred during the TMS Winter meeting, March 15–17, 2004, in Charlotte, NC, under
the auspices of the TMS Alloy Phases Committee and the co-sponsorship of the TMS-ASM Phase Transformations Committee. 相似文献
5.
Kahler Christopher W.; Read Jennifer P.; Wood Mark D.; Palfai Tibor P. 《Canadian Metallurgical Quarterly》2003,17(3):226
Structural equation modeling was used to test the mediational role of social environmental selection on alcohol use in cross-sectional samples of 447 students from a rural state university and 421 students from an urban private university. Results showed that male gender, White ethnicity, and sensation seeking were uniquely associated with greater alcohol use. Mediational analyses indicated that socioenvironmental factors (i.e., Greek involvement, friends' approval of drinking/getting drunk) were positively associated with alcohol use and significantly accounted for parts of the effects of ethnicity and sensation seeking, but not gender, on alcohol use. Results suggest that White students and those high on sensation seeking may drink more heavily in college, in part because they select social environments in which alcohol use is encouraged. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
6.
Cellular plates are constructed from two base plates and an orthogonal grid of stiffeners welded between them. Halved rolled
I-section stiffeners are used for fabrication aspects. The torsional stiffness of cells makes the plate very stiff. In the
case of uniaxial compression the buckling constraint is formulated on the basis of the classic critical stress derived from
the Huber’s equation for orthotropic plates. The cost function contains the cost of material, assembly and welding and is
formulated according to the fabrication sequence. The unknown variables are the base plate thicknesses, height of stiffeners
and numbers of stiffeners in both directions. The cellular plate is lighter and cheaper than the plate stiffened on one side.
The Particle Swarm Optimization and the IOSO techniques are used to find the optimum. PSO contains crazy bird and dynamic
inertia reduction criteria, IOSO is based on a response surface technology. 相似文献
7.
Bruno Gabel Denis Thiéry Vaclav Suchy Frédéric Marion-Poll Peter Hradsky Pavel Farkas 《Journal of chemical ecology》1992,18(5):693-701
The European grapevine moth (EGVM),Lobesia botrana, is a major pest of grapes in Europe. Females are attracted to a nonhost plant: tansy (Tanacetum vulgare L.), which is a common weed in Slovakian vineyards. A steam distillate extract of tansy flowers was analyzed by means of a GC-EAG technique to screen constituents detected by the olfactory receptors of EGVM females. From more than 200 GC peaks, nine peaks corresponding to monoterpenoids released an EAG response in more than 70% of the females (N=15):p-cymene,d-limonene,-thujene,-thujone,-thujone, thujyl alcohol, terpinene-4-ol, (Z)-verbenol, and piperitone. The steam distillate of tansy as well as a synthetic blend of identified compounds released consistent attraction in a field cage. The use of nonhost plants and host plant odors in integrated pest management is discussed. 相似文献
8.
Galina M. Viryasova Ekaterina A. Golenkina Tibor Hianik Nataliya V. Soshnikova Nina G. Dolinnaya Tatjana V. Gaponova Yulia M. Romanova Galina F. Sudina 《International journal of molecular sciences》2021,22(5)
Neutrophil-mediated innate host defense mechanisms include pathogen elimination through bacterial phagocytosis, which activates the 5-lipoxygenase (5-LOX) product synthesis. Here, we studied the effect of synthetic oligodeoxyribonucleotides (ODNs), which mimic the receptor-recognized sites of bacterial (CpG-ODNs) and genomic (G-rich ODNs) DNAs released from the inflammatory area, on the neutrophil functions after cell stimulation with Salmonella typhimurium. A possible mechanism for ODN recognition by Toll-like receptor 9 (TLR9) and RAGE receptor has been proposed. We found for the first time that the combination of the magic peptide LRR11 from the leucine-rich repeat (LRR) of TLR9 with the CpG-ODNs modulates the uptake and signaling from ODNs, in particular, dramatically stimulates 5-LOX pathway. Using thickness shear mode acoustic method, we confirmed the specific binding of CpG-ODNs, but not G-rich ODN, to LRR11. The RAGE receptor has been shown to play an important role in promoting ODN uptake. Thus, FPS-ZM1, a high-affinity RAGE inhibitor, suppresses the synthesis of 5-LOX products and reduces the uptake of ODNs by neutrophils; the inhibitor effect being abolished by the addition of LRR11. The results obtained revealed that the studied peptide-ODN complexes possess high biological activity and can be promising for the development of effective vaccine adjuvants and antimicrobial therapeutics. 相似文献
9.
The enantioselective hydrogenation of ethyl pyruvate to (S)-ethyl lactate over cinchonine- and -isocinchonine-modified Pt/Al2O3 catalysts was studied as a function of modifier concentration and reaction temperature. The maximum enantioselectivities obtained under the applied mild conditions were 89% ee using cinchonine (0.014 mmoldm–3, 1 bar H2, 23°C, 6% AcOH in toluene), and 76% ee in the case of -isocinchonine (0.14 mmoldm–3, 1 bar H2, –10°C, 6% AcOH in toluene). Since -isocinchonine of rigid structure exists only in anti-open conformation these data provide additional experimental evidence to support the former suggestion concerning the dominating role of anti-open conformation in these cinchona-modified enantioselective hydrogenations. 相似文献
10.
The development of adipose tissue in the chick embryo was investigated using two groups of fertile eggs which differed by
1.7-fold in their initial yolk lipid levels. The triacylglycerol content of the subcutaneous adipose depot in both groups
increased dramatically from day 12 of the 21-day embryonic period, attaining a maximal value just prior to hatching. During
this period, the amount of triacylglycerol deposited in the adipose tissue was very highly correlated with the amount of lipid
transferred from the yolk. The triacylglycerol content of the depot was also dependent on the initial yolk lipid content.
During the hatching period, the amount of adipose triacylglycerol remained approximately constant in the group with the higher
initial yolk lipid content but, in the case of the group with the lower initial yolk lipid levels, decreased by approximately
25%. The size distribution of adipocytes isolated from the tissue was determined by computerized image analysis microscopy.
The mean adipocyte diameter increased from approximately 6 to 35 μm between days 12 and 19, irrespective of the initial yolk
content, although development within the eggs with the lower initial yolk content resulted in a decrease in cell size over
the hatching period. Both the triacylglycerol and phospholipid fractions of the isolated adipocytes contained substantial
proportions (approximately 6%, w/w) of docosahexaenoic acid (DHA) at days 12 and 14, and lower levels of this fatty acid at
the later stages. The amount (mg/depot) of DHA in adipose triacylglycerol decreased dramatically over the hatching period.
The amount (mg/brain) of DHA in brain phospholipid increased by more than 5-fold between day 12 of development and hatching.
A possible explanation for the data may be that DHA is preferentially mobilized from adipose tissue in order to deliver the
fatty acid to the developing neural tissues in a form suitable for uptake. 相似文献