166 results match your criteria: "Peter the Great Saint Petersburg Polytechnic University[Affiliation]"

Transition to flowering is an important stage of plant development. Many regulatory modules that control floral transition are conservative across plants. This process is best studied for the model plant .

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Aberrant protein acetylation is strongly linked to tumorigenesis, and modulating acetylation through targeting histone deacetylase (HDAC) with small-molecule inhibitors has been the focus of clinical trials. However, clinical success on solid tumours, such as colorectal cancer (CRC), has been limited, in part because the cancer-relevant mechanisms through which HDAC inhibitors act remain largely unknown. Here, we have explored, at the genome-wide expression level, the effects of a novel HDAC inhibitor CXD101.

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Quench me if you can: Alpha-2-macroglobulin trypsin complexes enable serum biomarker analysis by MALDI mass spectrometry.

Biochimie

June 2021

Smorodintsev Research Institute of Influenza, Russian Ministry of Health, 197376, Prof. Popov St. 15/17, St. Petersburg, Russia; Peter the Great Saint Petersburg Polytechnic University, 194064, Politekhnicheskaya 29, St. Petersburg, Russia; Petersburg Nuclear Physics Institute named by B. P. Konstantinov of National Research Center "Kurchatov Institute", 188300, mkr. Orlova roshcha 1, Gatchina, Russia. Electronic address:

One of the main functions of alpha-2-macroglobulin (A2M) in human blood serum is the binding of all classes of protease. It is known that trypsin, after such interaction, possesses modified proteolytic activity. Trypsin first hydrolyzes two bonds in A2M's 'bait region', and the peptide VGFYESDVMGR is released from A2M.

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The polymer deformability under load and heating is the determining factor in calculating reinforced polymer structures used under heating. Deformability-load/temperature relations make it possible to calculate temperature stresses and deformations in bearing cross-sections of polymer structures such as chimneys, smokestacks, etc. The present study suggests a method of calculating deformability of polymers subjected to the temperature loads.

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According to the World Health Organization, human life expectancy has increased significantly around the world over the past century, but this process is inevitably accompanied by aging. Therefore, persons who have reached the elderly and senile age often become infirm, especially physically. As a result, such people find it increasingly difficult to make movements related to self-service and movement when using standard clothing and shoes.

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The most common causes of conducting a hip revision surgery after total hip replacement are aseptic loosening (aseptic instability) of the endoprosthesis, bone destruction as a result of contact with the endoprosthesis, and a periprosthetic fracture. These are the effects of load transfer to the bone tissue in arthroplasty resulting due to the difference in stiffness of the endoprosthesis and the bone. Titanium alloy is widely used in endoprostheses manufacturing because of its high biocompatibility, good wear properties, and corrosion resistance, but such endoprostheses are stiffer than the femur.

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Experimental determination and data-driven prediction of homotypic transmembrane domain interfaces.

Comput Struct Biotechnol J

October 2020

Center for Integrated Protein Science Munich (CIPSM) at the Lehrstuhl für Chemie der Biopolymere, Technische Universität München, Weihenstephaner Berg 3, 85354 Freising, Germany.

Interactions between their transmembrane domains (TMDs) frequently support the assembly of single-pass membrane proteins to non-covalent complexes. Yet, the TMD-TMD interactome remains largely uncharted. With a view to predicting homotypic TMD-TMD interfaces from primary structure, we performed a systematic analysis of their physical and evolutionary properties.

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Controlled growth of heterostructured nanowires and mechanisms of their formation have been actively studied during the last decades due to perspectives of their implementation. Here, we report on the self-catalyzed growth of axially heterostructured GaPN/GaP nanowires on Si(111) by plasma-assisted molecular beam epitaxy. Nanowire composition and structural properties were examined by means of Raman microspectroscopy and transmission electron microscopy.

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Copper-based composite materials strengthened with nanosized fullerene soot particles were produced by mechanical milling and hot pressing technology with a content of carbon up to 5 wt. %. The microstructure of the composite powders and the compacts prepared using them were examined by light microscopy, SEM, EDS, XRD, and XPS; hardness, heat conductivity, and tribological characteristics were measured.

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Ion signal detection at the true (unperturbed) cyclotron frequency instead of the conventional reduced cyclotron frequency has remained a formidable challenge since the inception of Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS). Recently, routine FT-ICR MS at the true cyclotron frequency has become a reality with the implementation of ICR cells with narrow aperture detection electrodes (NADEL). Here, we describe the development and implementation of the next generation of these cells, namely, a 2xNADEL ICR cell, which comprises four flat detect and four ∼45° cylindrical excite electrodes, enabling independent ion excitation and quadrupolar ion detection.

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Controversy in the description/identification of so-called intermediate phase(s) in PbHfO, stable in the range ∼420-480 K, has existed for a few decades. A synchrotron diffraction experiment on a partially detwinned crystal allowed the structure to be solved in the superspace group Imma(00γ)s00 (No. 74.

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Over the last few years, incidental thyroid nodules are being diagnosed with increasing frequency with the use of highly sensitive imaging techniques. The ultrasound thyroid gland examination, followed by the fine-needle aspiration cytology is the standard diagnostic approach. However, in cases of the follicular nature of nodules, cytological diagnosis is not enough.

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Background: There is a plethora of methods for genome-wide association studies. However, only a few of them may be classified as multi-trait and multi-locus, i.e.

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Interaction between water and composite films based on chitosan and chitin nanofibrils was studied. Isotherms of water vapor sorption by composite films were used to calculate partial values of entropy and enthalpy of sorbate; dependences of entropy and enthalpy on water sorption value were obtained. It was demonstrated that introducing chitin nanofibrils into chitosan matrix leads to decrease in sorption capacity of composite films.

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Extracellular vesicles (EV) are involved in important processes of glioblastoma multiforme (GBM), including malignancy and invasion. EV secreted by glioblastoma cells may cross the hematoencephalic barrier and carry molecular cargo derived from the tumor into the peripheral circulation. Therefore, the determination of the molecular composition of exosomes released by glioblastoma cells seems to be a promising approach for the development of non-invasive methods of the detection of the specific exosomal protein markers in the peripheral blood.

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Biological Safety and Biodistribution of Chitosan Nanoparticles.

Nanomaterials (Basel)

April 2020

ITMO University, Laboratory of Digital and Display Holography, 49 Kronverksky ave., 197101 Saint Petersburg, Russia.

The effect of unmodified chitosan nanoparticles with a size of ~100 nm and a weakly positive charge on blood coagulation, metabolic activity of cultured cardiomyocytes, general toxicity, biodistribution, and reactive changes in rat organs in response to their single intravenous administration at doses of 1, 2, and 4 mg/kg was studied. Chitosan nanoparticles (CNPs) have a small cytotoxic effect and have a weak antiplatelet and anticoagulant effect. Intravenous administration of CNPs does not cause significant hemodynamic changes, and 30 min after the CNPs administration, they mainly accumulate in the liver and lungs, without causing hemolysis and leukocytosis.

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The paper suggests a method for optimization of the process of integrated tests for complex technical equipment of automotive, aviation, and rocket systems based on an analysis of efficiency dynamics models. The method makes it possible to determine scopes of ground tests for complex technical equipment, which are minimally required to start field tests under the necessity to combine ground and field development. Exponential models of complex systems' development are used as efficiency dynamics models for the whole testing process as well as efficiency dynamics models at various levels of the hierarchy of tests.

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A method for simple and fast (30-60 s) synthesis of spherical "FeO core-carbon shell" structures by atmospheric pressure aerosol pyrolysis of benzoic acid in dimethylformamide solutions containing dispersed FeO nanoparticles is described. It has been experimentally shown that it is possible to control both the size of the core-shell particles and the size of FeO grains and their amount in the particle core by the variation of benzoic acid concentration in solution and using pre-stabilized by mannitol iron oxide nanoparticles. It has been found that particles with an average size of 250-350 nm are formed at the concentration of benzoic acid in the range 0.

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During host colonization, bacteria use the alarmones (p)ppGpp to reshape their proteome by acting pleiotropically on DNA, RNA, and protein synthesis. Here, we elucidate how the initiating ribosome senses the cellular pool of guanosine nucleotides and regulates the progression towards protein synthesis. Our results show that the affinity of guanosine triphosphate (GTP) and the inhibitory concentration of ppGpp for the 30S-bound initiation factor IF2 vary depending on the programmed mRNA.

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Novel thermostable variants of glucoamylase (GA) from filamentous fungus Aspergillus awamori X100 were constructed using the directed evolution approach based on random mutagenesis by error-prone PCR of the catalytic domain region of glucoamylase gene located on a new episomal expression vector pPEHα in Pichia pastoris cells. Out of 3000 yeast transformants screened, six new thermostable GA variants with amino acid substitutions Val301Asp, Thr390Ala, Thr390Ala/Ser436Pro, Leu7Met/His391Tyr, Asn9His/Ile82Phe and Ser8Arg/Gln338Leu were identified and studied. To estimate the effect of each substitution in the double mutants, we have constructed the relevant single mutants of GA by site-directed mutagenesis and analyzed their thermal properties.

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Motivation: Epistasis, the context-dependence of the contribution of an amino acid substitution to fitness, is common in evolution. To detect epistasis, fitness must be measured for at least four genotypes: the reference genotype, two different single mutants and a double mutant with both of the single mutations. For higher-order epistasis of the order n, fitness has to be measured for all 2n genotypes of an n-dimensional hypercube in genotype space forming a "combinatorially complete dataset".

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Effect of alpha-lactalbumin and lactoferrin oleic acid complexes on chromatin structural organization.

Biochem Biophys Res Commun

November 2019

Department of Molecular and Radiation Biophysics, Petersburg Nuclear Physics Institute Named by B. P. Konstantinov of National Research Center "Kurchatov Institute", 188300, mkr. Orlova roshcha 1, Gatchina, Russia; National Research Centre Kurchatov Institute, 123182, Akademika Kurchatova Sq. 1, Moscow, Russia; Department of Molecular Biology of Viruses, Smorodintsev Research Institute of Influenza, Russian Ministry of Health, 197376, Prof. Popov St. 15/17, St. Petersburg, Russia; Department of Molecular Genetics, Federal State Budgetary Scientific Institution "Institute of Experimental Medicine", 197376, Akademika Pavlova St. 12, St. Petersburg, Russia.

Article Synopsis
  • The study investigates the interactions of multimeric complexes formed by alpha-lactalbumin and lactoferrin with oleic acid, focusing on their potential pro-apoptotic effects in tumor cells.
  • Using small-angle neutron scattering (SANS), the research reveals that alpha-lactalbumin forms complexes with polydisperse oleic acid micelles, while lactoferrin forms a uniform nanoscale particle system.
  • Additionally, both complexes appear to influence chromatin structure in isolated nuclei, suggesting their role in exhibiting specific anti-tumor activities.
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Reflectance of graphene-coated dielectric plates in the framework of Dirac model: joint action of energy gap and chemical potential.

J Phys Condens Matter

December 2019

Central Astronomical Observatory at Pulkovo of the Russian Academy of Sciences, St.Petersburg, 196140, Russia. Institute of Physics, Nanotechnology and Telecommunications, Peter the Great Saint Petersburg Polytechnic University, St.Petersburg, 195251, Russia.

We investigate the reflectance of a dielectric plate coated with a graphene sheet which possesses the nonzero energy gap and chemical potential at any temperature. The general formalism for the reflectance using the polarization tensor is presented in the framework of Dirac model. It allows calculation of the reflectivity properties for any material plate coated with real graphene sheet on the basis of first principles of quantum electrodynamics.

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Minimal Age-Related Alterations in Behavioral and Hematological Parameters in Trace Amine-Associated Receptor 1 (TAAR1) Knockout Mice.

Cell Mol Neurobiol

March 2020

Institute of Translational Biomedicine and Saint Petersburg University Hospital, Saint Petersburg State University, Universitetskaya nab., 7-9, Saint Petersburg, Russia, 199034.

Since the discovery in 2001, the G protein-coupled trace amine-associated receptor 1 (TAAR1) has become an important focus of research targeted on evaluation of its role in the central nervous system (CNS). Meanwhile, impact of TAAR1 in the peripheral organs is less investigated. Expression of TAAR1 was demonstrated in different peripheral tissues: pancreatic β-cells, stomach, intestines, white blood cells (WBC), and thyroid.

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In this work, we developed a simple method for the preparation of N-(3-azido-2-hydroxypropyl)chitosan. We compared the antibacterial activity of N-(3-azido-2-hydroxypropyl)chitosans and previously synthesized N-(2-azidoethyl)chitosans. N-(3-azido-2-hydroxypropyl)chitosans possess higher antibacterial effect which is comparable with that of ampicillin and gentamicin.

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