Publications by authors named "Igor Ivanov"

Bioreactor-grown plant cells have emerged as a sustainable, high-quality source of plant biomass and bioactive phytochemicals alternative to overcollection of pharmaceutically important wild plant species. At the same time, concerns were raised about the potential biosynthetic instability of plant cell cultures during long-term bioreactor cultivation, which was rarely investigated. In this work, this concern was addressed by performing the first long-term (1.

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: Coronary microvascular dysfunction (CMD) is emerging as a critical factor in patients presenting with anginal symptoms without obstructive coronary artery disease (CAD). This study aims to investigate the relationship between invasive measurements of coronary flow reserve (CFR) and the index of microcirculatory resistance (IMR) using thermodilution techniques, compared to non-invasive assessments of CFR with transthoracic Doppler echocardiography (TDE). : In this observational prospective cross-sectional study, a total of 49 patients, clinically characterized as having angina with no obstructive CAD (ANOCA) or ischemia with no obstructive CAD (INOCA), underwent both TDE and invasive coronary angiography (ICA) followed by thermodilution assessment of CFR and IMR.

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Vortex states of photons, electrons, and other particles are freely propagating wave packets with helicoidal wave fronts winding around the axis of a phase vortex. A particle prepared in a vortex state carries a nonzero orbital angular momentum projection on the propagation direction, a quantum number that has never been exploited in experimental particle and nuclear physics. Low-energy vortex photons, electrons, neutrons, and helium atoms have been demonstrated in experiment and found numerous applications, and there exist proposals of boosting them to higher energies.

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Bacterial and viral RNA polymerases are promising targets for the development of new transcription inhibitors. One of the potential blockers of RNA synthesis is 7,8-dihydro-8-oxo-1,-ethenoadenine (oxo-εA), a synthetic compound that combines two adenine modifications: 8-oxoadenine and 1,-ethenoadenine. In this study, we synthesized oxo-εA triphosphate (oxo-εATP) and showed that it could be incorporated by the RNA-dependent RNA polymerase of SARS-CoV-2 into synthesized RNA opposite template residues A and G in the presence of Mn ions.

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Background: Skin melanoma is a highly metastatic cancer with an increasing global incidence. Despite advancements in immunotherapy, new treatment strategies based on tumor biology are essential for improving outcomes and developing novel therapies. Autophagy plays a critical role in melanoma cell metabolism and affects the tumor microenvironment (TME).

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Background: A considerable number of symptomatic patients leave the cardiac catheterization lab without a definitive diagnosis for their symptoms because no epicardial stenoses are found. The significance of disorders of coronary microvasculature and vasomotion as the cause of symptoms and signs of ischemia has only recently been appreciated. Today we have a wide spectrum of invasive coronary physiology tools but little is known about when and how these tools are used in clinical practice.

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Accurate and high coverage genome assemblies are the basis for downstream analysis of metagenomic studies. Long-read sequencing technology is an ideal tool to facilitate the assemblies of metagenome, except for the drawback of usually producing reads with high sequencing error rate. Many polishing tools were developed to correct the sequencing error, but most are designed on the ground of one or two species.

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Article Synopsis
  • The human genome consists of six Arachidonic Acid (AA) lipoxygenase genes, with enzymes that play roles in various disorders, including inflammation and metabolic issues.
  • Humans have two main AA 15-lipoxygenating enzymes, ALOX15 and ALOX15B, which have been linked to different reaction pathways despite being part of the same enzyme family.
  • The diversity of mammalian ALOX isoforms and differing enzyme names can be confusing, highlighting the need to clarify their biological functions and regulatory mechanisms.
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  • This study investigated how irradiation from krypton and helium ions affects the structure and composition of high-entropy alloys (HEAs) at room temperature, specifically CoCrFeNi and CoCrFeMnNi.
  • Findings showed that while elemental distribution remained stable, blisters formed on nickel surfaces due to the irradiation process, with large ones averaging 3.8 μm in diameter.
  • The research noted significant changes in lattice parameters, stress levels (compressive and tensile), and dislocation densities in the HEAs post-irradiation, indicating differences in material responses between the two alloys.
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The paper presents the results of studying the structure and phase state of tungsten and tungsten-copper alloy after pulsed action of compression plasma flows and irradiation with helium ions. The compression plasma flows were used to modify the surface layer of tungsten, as well as to create an alloy based on tungsten and copper. Using scanning electron microscopy and X-ray structural analysis, the formation of radiation defects on the tungsten surface was detected in the form of local areas of exfoliation and destruction, which begin to form at helium ion irradiation doses of 2 × 10 cm.

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Article Synopsis
  • * The study examined changes in their structure and surface morphology after irradiation, revealing the development of a porous surface with microchannels, and noted that CoCrFeMnNi had smaller blister sizes compared to CoCrFeNi.
  • * Results showed that while elemental compositions remained stable under high temperatures, CoCrFeMnNi demonstrated better radiation resistance by forming compressive macrostresses and a higher dislocation density compared to CoCrFeNi.
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Photochemical transformations of small molecules, such as -substituted benzaldehydes, in the absence of a photocatalyst are significantly underexplored and may reveal unexpected outcomes. In the present paper, we showed that 2-(2-formylphenoxy)acetic acid and its esters undergo photocyclization into chromanone and benzofuranone derivatives under 365 nm irradiation. The reaction occurs exclusively in dimethyl sulfoxide and can be used to efficiently obtain hydroxychromanones in good yields (27-91%).

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The photoelectric effect is not truly instantaneous but exhibits attosecond delays that can reveal complex molecular dynamics. Sub-femtosecond-duration light pulses provide the requisite tools to resolve the dynamics of photoionization. Accordingly, the past decade has produced a large volume of work on photoionization delays following single-photon absorption of an extreme ultraviolet photon.

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Existing methods for the mass detection of viruses are limited to the registration of small amounts of a viral genome or specific protein markers. In spite of high sensitivity, the applied methods cannot distinguish between virulent viral particles and non-infectious viral particle debris. We report an approach to solve this long-standing challenge using the SARS-CoV-2 virus as an example.

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Seasonal influenza remains a serious global health problem, leading to high mortality rates among the elderly and individuals with comorbidities. Vaccination is generally accepted as the most effective strategy for influenza prevention. While current influenza vaccines are effective, they still have limitations, including narrow specificity for certain serological variants, which may result in a mismatch between vaccine antigens and circulating strains.

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SARS-CoV-2 variants have evolved over time in recent years, demonstrating immune evasion of vaccine-induced neutralizing antibodies directed against the original S protein. Updated S-targeted vaccines provide a high level of protection against circulating variants of SARS-CoV-2, but this protection declines over time due to ongoing virus evolution. To achieve a broader protection, novel vaccine candidates involving additional antigens with low mutation rates are currently needed.

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Rabies is a zoonotic disease with high lethality. Most human deaths are associated with the bites received from dogs and cats. Vaccination is the most effective method of preventing rabies disease in both animals and humans.

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(LEXSY) system is an inexpensive and effective expression approach for various research and medical purposes. The stated advantages of this system are the possibility of obtaining the soluble product in the cytoplasm, a high probability of correct protein folding with a full range of post-translational modifications (including uniform glycosylation), and the possibility of expressing multi-subunit proteins. In this paper, a LEXSY expression system has been employed for obtaining the receptor binding domain (RBD) of the spike-protein of the SARS-CoV-2 virus and the homopentameric acetylcholine-binding protein (AChBP) from .

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Article Synopsis
  • The study focuses on the molecular mechanism of gausemycins, which are a class of antibiotics, and details the isolation of new variants named gausemycins C, D, E, and F.
  • It was found that gausemycins A and B exhibit antimicrobial properties that depend on calcium concentrations, requiring more calcium than daptomycin but less than other antibiotics like malacidine.
  • The research confirmed that gausemycins affect bacterial membranes by forming pores, with the ability to do so influenced by the composition of the lipid membranes and calcium levels, as suggested by NMR studies on gausemycin B.
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Affinity chromatography resins that are obtained by conjugation of matrices with proteins of bacterial origin, like protein A, are frequently used for the purification of numerous therapeutic monoclonal antibodies. This article presents the development of a biocatalytic method for the production of novel affinity resins with an immobilized mutant form of protein A via sortase A mediated reaction. The conditions for activation of the agarose Seplife 6FF matrix, selection of different types of linkers with free amino groups and conditions for immobilization of recombinant protein A on the surface of the activated matrix were studied.

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This paper describes a fast and flexible microfabrication method for thermal conductivity gas sensors useful in high-temperature applications. The key parts of the sensor, the microheater and the package, were fabricated from glass-coated platinum wire and the combination of laser micromilling (ablation) of already-sintered monolithic ceramic materials and thick-film screen-printing technologies. The final thermal conductivity gas sensor was fabricated in the form of a complete MEMS device in a metal ceramic package, which could be used as a compact miniaturized surface-mounted device for soldering to standard PCB.

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SLURP-1 is a three-finger human protein targeting nicotinic acetylcholine receptors (nAChRs). The recombinant forms of SLURP-1 produced in differ in added fusion fragments and in activity. The closest in sequence to the naturally occurring SLURP-1 is the recombinant rSLURP-1, differing by only one additional N-terminal Met residue.

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In Phi29-α-hemolysin (α-HL) nanopore sequencing systems, a strong electrochemical signal is dependent on a high concentration of salt. However, high salt concentrations adversely affect polymerase activity. Sequencing by synthesis (SBS) requires the use of phi29 polymerase without exonuclease activity to prevent the degradation of modified nucleotide tags; however, the lack of exonuclease activity also affects polymerase processivity.

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Spontaneous coronary artery dissection (SCAD) is a rare but increasingly recognized cause of acute coronary syndrome (ACS) with recent advancements in cardiac imaging facilitating its identification. However, SCAD is still often misdiagnosed due to the absence of angiographic hallmarks in a significant number of cases, highlighting the importance of meticulous interpretation of angiographic findings and, when necessary, additional usage of intravascular imaging to verify changes in arterial wall integrity and identify specific pathoanatomical features associated with SCAD. Accurate diagnosis of SCAD is crucial, as the optimal management strategies for patients with SCAD differ from those with atherosclerotic coronary disease.

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