Publications by authors named "Panchenko T"

Article Synopsis
  • Antibody responses are crucial for defending against SARS-CoV-2 by stopping the virus from entering cells, and a new assay called 2D-MBBA has been developed to measure various antibody isotypes simultaneously.
  • This assay was used to analyze IgG, IgM, and IgA levels against the spike protein and its variants, and machine learning significantly improved predictions of how well these antibodies neutralize the virus in convalescent patients.
  • The method can differentiate between antibody profiles in convalescent and vaccinated individuals and offers the potential for rapid testing of neutralization efficacy against new variants and pathogens using just a small blood sample.
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Article Synopsis
  • - Understanding antibody responses to SARS-CoV-2 is crucial for effective COVID-19 containment strategies; however, predicting neutralization capacity remains challenging, as convalescent patients show variable outcomes.
  • - A study examined sera from 101 recovered healthcare workers, revealing sustained IgG levels against SARS-CoV-2 proteins, but most individuals had low neutralization ability, with only 6% demonstrating high neutralizing titers.
  • - Findings suggest that possessing a variety of antibody isotypes (IgG, IgM, IgA) correlates with stronger neutralization responses, indicating that a broader antibody repertoire may enhance SARS-CoV-2 neutralization effectiveness.
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  • The study focuses on developing a cost-effective multiplex bead binding assay (MBBA) for analyzing protein-ligand interactions without the need for specialized equipment or expensive reagents.
  • The method innovatively uses biotin-streptavidin interactions and fluorescently labeled magnetic beads to enhance experimental throughput.
  • The effectiveness of this new MBBA method is demonstrated by characterizing antibodies against SARS-CoV-2, significantly improving efficiency and reducing the amount of antigen required compared to traditional methods.
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  • * Research on convalescent sera from COVID-19 patients showed that only a small number of antibodies specifically targeted the ACE2-interacting surface on the spike protein, indicating potential immune evasion by the virus.
  • * Selection experiments revealed that while unbiased approaches favored antibodies targeting regions away from ACE2IS, biased methods successfully identified ACE2IS-binding antibodies, suggesting that the ACE2IS has evolved to be less immunogenic, which is key for vaccine development.
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  • - The COVID-19 pandemic is a persistent global challenge, where host immunity is crucial for protection, with the spike protein on SARS-CoV-2 being a key target for neutralizing antibodies through its interaction with the ACE2 receptor.
  • - Research involving an RBD mutant showed that only a small portion of antibodies from recovered COVID-19 patients targeted the critical ACE2-interacting surface, indicating limited immune recognition of this viral component.
  • - Different antibody selection methods revealed that while unbiased selection favored regions outside the ACE2IS, biased selection was effective in identifying ACE2IS-targeting antibodies, suggesting that the ACE2IS is less immunogenic, which is significant for future vaccine development.
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Complex organisms can rapidly induce select genes in response to diverse environmental cues. This regulation occurs in the context of large genomes condensed by histone proteins into chromatin. The sensing of pathogens by macrophages engages conserved signalling pathways and transcription factors to coordinate the induction of inflammatory genes.

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The purpose of the work is to develop individual treatment regimens for children with secretory otitis media (SOM) depending on the results of an in-depth examination of them, in particular, the identification of Epstein-Barr virus (EBV), the presence of pathogenic microflora in the nasopharynx and the results of a level 1 immunogram. Laboratory examination for the presence of serological markers: IgM to the capsid complex (VCA), IgG to the early antigen (EA) and the nuclear antigen EBNA in the blood serum by enzyme-linked immunosorbent assay (ELISA). 68 children were exposed, children's department of the 30th hospital.

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Aim: To study the efficacy and tolerability of cortexin in the treatment of cognitive dysfunction in children.

Material And Methods: The study included 635 patients, aged 3-7 years. Patients were divided into 4 clinical groups: group 1 (269 children with attention deficit hyperactivity disorder (ADHD)), group 2 (215 children with speech delay), group 3 (82 patients with the consequences of a perinatal lesion of the central nervous system), group 4 (69 patients with asthenic/neurotic syndrome).

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  • ATP-dependent chromatin remodellers help control access to genetic information by altering the positions of nucleosomes, but the way they identify and interact with different nucleosome types is not fully understood.
  • A study used a DNA-barcoded mononucleosome library to evaluate the activity of human ISWI family remodellers and found that their accessory subunits can differentiate between nucleosomes with various modifications.
  • The research revealed that the nucleosome's acidic patch is crucial for the activity of ISWI, CHD, and SWI/SNF remodellers, indicating that this region serves as an important interaction site that can be modulated by nearby nucleosome modifications.
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  • - Histone covalent modifications, especially new lysine acylations like crotonylation, butyrylation, and propionylation, play a crucial role in epigenetic regulation through 'reader' modules.
  • - The double PHD finger (DPF) domains of proteins MOZ and DPF2 show a strong preference for binding to crotonylated histones, as revealed by detailed structural studies.
  • - Experiments, including immunofluorescence and ChIP-qPCR, demonstrate that MOZ interacts specifically with crotonylated histones, highlighting a novel regulatory mechanism in gene expression influenced by histone modification.
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  • Histone modifications play a key role in epigenetic regulation, with proteins like bromodomains binding to acetylated lysines, but new non-acetyl modifications like crotonylation are being studied.
  • The AF9 YEATS domain has been found to preferentially bind to crotonyllysine instead of acetyllysine, showcasing specific interactions due to its unique structural features.
  • Experimental findings indicate that AF9 interacts with crotonylated histone H3 and enhances gene expression, linking crotonylation directly to active transcription processes in cells.
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The centromere is the locus on the chromosome that acts as the essential connection point between the chromosome and the mitotic spindle. A histone H3 variant, CENP-A, defines the location of the centromere, but centromeric chromatin consists of a mixture of both CENP-A-containing and H3-containing nucleosomes. We report a surprisingly uniform pattern of primarily monomethylation on lysine 20 of histone H4 present in short polynucleosomes mixtures of CENP-A and H3 nucleosomes isolated from functional centromeres.

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The centromere-defined by the presence of nucleosomes containing the histone H3 variant, CENP-A-is the chromosomal locus required for the accurate segregation of chromosomes during cell division. Although the sequence determinants of human CENP-A required to maintain a centromere were reported, those that are required for early steps in establishing a new centromere are unknown. In this paper, we used gain-of-function histone H3 chimeras containing various regions unique to CENP-A to investigate early events in centromere establishment.

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The centromere, responsible for chromosome segregation during mitosis, is epigenetically defined by CENP-A containing chromatin. The amount of centromeric CENP-A has direct implications for both the architecture and epigenetic inheritance of centromeres. Using complementary strategies, we determined that typical human centromeres contain ∼400 molecules of CENP-A, which is controlled by a mass-action mechanism.

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The histone H2A-H2B heterodimer is an integral component of the nucleosome. The cellular localization and deposition of H2A-H2B into chromatin is regulated by numerous factors, including histone chaperones such as nucleosome assembly protein 1 (Nap1). We use hydrogen-deuterium exchange coupled to mass spectrometry to characterize H2A-H2B and Nap1.

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Centromeres are chromosomal loci required for accurate segregation of sister chromatids during mitosis. The location of the centromere on the chromosome is not dependent on DNA sequence, but rather it is epigenetically specified by the histone H3 variant centromere protein A (CENP-A). The N-terminal tail of CENP-A is highly divergent from other H3 variants.

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The centromere is the chromosomal locus that ensures fidelity in genome transmission at cell division. Centromere protein A (CENP-A) is a histone H3 variant that specifies centromere location independently of DNA sequence. Conflicting evidence has emerged regarding the histone composition and stoichiometry of CENP-A nucleosomes.

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Centromeres are defined by the presence of chromatin containing the histone H3 variant, CENP-A, whose assembly into nucleosomes requires the chromatin assembly factor HJURP. We find that whereas surface-exposed residues in the CENP-A targeting domain (CATD) are the primary sequence determinants for HJURP recognition, buried CATD residues that generate rigidity with H4 are also required for efficient incorporation into centromeres. HJURP contact points adjacent to the CATD on the CENP-A surface are not used for binding specificity but rather to transmit stability broadly throughout the histone fold domains of both CENP-A and H4.

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Centromere protein A (CENP-A) is a histone H3 variant that marks centromere location on the chromosome. To study the subunit structure and folding of human CENP-A-containing chromatin, we generated a set of nucleosomal arrays with canonical core histones and another set with CENP-A substituted for H3. At the level of quaternary structure and assembly, we find that CENP-A arrays are composed of octameric nucleosomes that assemble in a stepwise mechanism, recapitulating conventional array assembly with canonical histones.

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Maintenance of genome stability during cell division depends on establishing correct attachments between chromosomes and spindle microtubules. Correct, bioriented attachments are stabilized, whereas incorrect attachments are selectively destabilized. This process relies largely on increased phosphorylation of kinetochore substrates of Aurora B kinase at misaligned versus aligned kinetochores.

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Mass spectrometry-based hydrogen/deuterium exchange (H/DX) has been used to define the polypeptide backbone dynamics of full-length methyl CpG binding protein 2 (MeCP2) when free in solution and when bound to unmethylated and methylated DNA. Essentially the entire MeCP2 polypeptide chain underwent H/DX at rates faster than could be measured (i.e.

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The centromere serves as the control locus for chromosome segregation at mitosis and meiosis. In most eukaryotes, including mammals, the location of the centromere is epigenetically defined. The contribution of both genetic and epigenetic determinants to centromere function is the subject of current investigation in diverse eukaryotes.

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Article Synopsis
  • Researchers investigated how varying levels of fluorinated amino acids affect the function and stability of an enzyme called chloramphenicol acetyltransferase (CAT).
  • They found that replacing all leucine residues with 5',5',5'-trifluoroleucine (TFL) retains enzymatic activity at room temperature and improves secondary structure, but reduces stability when exposed to heat and solvents.
  • While the enzyme's catalytic activity remains similar to the wild type, increasing TFL levels leads to decreased stability, indicating that enhanced structure from fluorination doesn’t guarantee better overall stability.
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Cardiodepressive and arrhythmogenic properties of cordarone were studied on cat in conditions of experimental acute ischemia and myocardial infarction upon intravenous infusion. The obtained results showed an increase cordarone cardiotoxicity and arrhythmogenic properties in conditions of myocardial infarction. No reliable difference was observed in dynamics of cordarone-induced changes in ECG parameters in animals with myocardial ischemia of various duration and intact animals.

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