Publications by authors named "Polyakova S"

Background: The COVID-19 pandemic has led to the rapid development of new vaccines and methods of testing vaccine-induced immunity. Despite the extensive research that has been conducted on the level of specific antibodies, less attention has been paid to studying the avidity of these antibodies. The avidity of serum antibodies is associated with a vaccine showing high effectiveness and reflects the process of affinity maturation.

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Article Synopsis
  • - Fluorescently labeled (strept)avidins are commonly used to detect biotinylated molecules in immunology and histochemistry, but they can also bind to various glycans, including components of blood group antigens and other oligosaccharides.
  • - This binding occurs in a dose-dependent manner, meaning that the presence of certain polymeric glycan conjugates can inhibit this interaction, but monomeric forms do not have the same effect.
  • - The ability of (strept)avidins to bind glycans may lead to inaccuracies in carbohydrate sample analysis, suggesting that researchers should avoid using excessive amounts of (strept)avidin in their experiments to minimize these errors.
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Glycan-binding specificity was studied for Jacalin, RCA 120, SBA, PHA-L, PHA-E, WGA, UEA, AAL, LTL, LEL, SNA, DSA, LCA, MAH and Con A, lectins widely used in histochemistry. Oligosaccharide- and polysaccharide-based glycan arrays were applied. Expected specificity was confirmed for only 6 of the 15 lectins and the glycan binding profiles of some lectins were dramatically broader than generally accepted.

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Viscumin, a lectin used in anti-cancer therapy, was originally considered as βGal recognizing protein; later, an ability to bind 6'-sialyl N-acetyllactosamine (6'SLN) terminated gangliosides was found. Here we probed viscumin with a printed glycan array (PGA) containing a large number of mammalian sulfated glycans, and found a strong binding to glycans with 6-O-SuGal moiety as lactose, N-acetyllactosamine (LN), di-N-acetyllactosamine (LacdiNAc), and even 6-O-SuGalNAcα (but not SiaTn). Also, the ability to bind some of αGal terminated glycans, including Galα1-3Galβ1-4GlcNAc, was observed.

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Previous studies have shown that in the blood of healthy donors (1) there are no natural antibodies against sialylated glycoproteins, which contain Neu5Acα (N-acetylneuraminic acid) as the most widespread form of human sialic acid, and (2) there is a moderate level of antibodies capable of binding unnatural oligosaccharides, where Neu5Ac is beta-linked to a typical mammalian glycan core. In the present study, we investigated antibodies against βNeu5Ac in more detail and verified the presence of Kdn (2-keto-3-deoxy- D-glycero-D-galacto-nonulosonic acid) as a possible cause behind their appearance in humans, taking into account the expected cross-reactivity to Kdn glycans, which are found in bacterial glycoconjugates in both the α- and β-forms. We observed the binding of peripheral blood immunoglobulins to sialyllactosamines (where "sialyl" is Kdn or neuraminic acid) in only a very limited number of donors, while the binding to monosaccharide Kdn occurred in all samples, regardless of the configuration of the glycosidic bond of the Kdn moiety.

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Purpose: To compare the efficacy and safety of ketoprofen plasters and diclofenac plasters after 3 weeks of administration in patients with osteoarthritis-related knee pain.

Methods: This multicenter, randomized, active-controlled, open-label, parallel-group, noninferiority phase III study randomized 236 adults with osteoarthritis-related knee pain for 3 weeks with ketoprofen plaster 30 mg twice daily (n = 118) or diclofenac plaster 15 mg once daily (n = 118). The primary efficacy end point was the mean change from baseline to week 3 in the mean knee pain intensity score during walking, as measured by a 100-mm visual analog scale with a predefined noninferiority margin of 10.

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Unlabelled: The results of epidemiological studies as well as statistical data show that in recent years the dental morbidity rate in the world has remained stable at a high level. Inflammatory diseases of periodontal tissues, in particular generalized forms of periodontitis, reach 80% in the world. The tendency of increasing the prevalence rate of these diseases in Ukraine, 60-99%, is being observed nowadays.

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The human gut microbiota is currently seen as an important factor that can promote autism spectrum disorder (ASD) development in children. This study aimed to detect differences in the taxonomic composition and content of bacterial genes encoding key enzymes involved in the metabolism of neuroactive biomarker compounds in the metagenomes of gut microbiota of children with ASD and neurotypical children. A whole metagenome sequencing approach was used to obtain metagenomic data on faecal specimens of 36 children with ASD and 21 healthy neurotypical children of 3-5 years old.

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We report here a draft genome sequence of sp. ASD88, a strain from the intestinal microbiota of a child with autism spectrum disorder, representing a previously undescribed species of the genus The assembled sequence consists of 88 scaffolds, and the total size is 2.59 Mb.

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Pancreatology Club Professional Medical Community, 1A.S. Loginov Moscow Clinical Research and Practical Center, Moscow Healthcare Department, Moscow; 2A.

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We describe APS1 in a boy with generalized lipodystrophy, oral candidiasis, autoimmune hepatitis and adrenal insufficiency. It is the first time when generalized lipodystrophy is associated with APS1.

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We represented a case history of multiple hepatic adenomas in an adolescent with severe clinical course of glycogen storage disease type lb (compound heterozygous mutations c.1042_1043delCT and c.817G>A in the SLC37A4).

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A series of stable organosuperbases, N-alkyl- and N-aryl-1,3-dialkyl-4,5-dimethylimidazol-2-ylidene amines, were efficiently synthesized from N,N'-dialkylthioureas and 3-hydroxy-2-butanone and their basicities were measured in acetonitrile. The derivatives with tert-alkyl groups on the imino nitrogen were found to be more basic than the tBuP(1) (pyrr) phosphazene base in acetonitrile. The origin of the high basicity of these compounds is discussed.

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Details about molecular membrane dynamics in living cells, such as lipid-protein interactions, are often hidden from the observer because of the limited spatial resolution of conventional far-field optical microscopy. The superior spatial resolution of stimulated emission depletion (STED) nanoscopy can provide new insights into this process. The application of fluorescence correlation spectroscopy (FCS) in focal spots continuously tuned down to 30 nm in diameter distinguishes between free and anomalous molecular diffusion due to, for example, transient binding of lipids to other membrane constituents, such as lipids and proteins.

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Cholesterol-mediated lipid interactions are thought to have a functional role in many membrane-associated processes such as signalling events. Although several experiments indicate their existence, lipid nanodomains ('rafts') remain controversial owing to the lack of suitable detection techniques in living cells. The controversy is reflected in their putative size of 5-200 nm, spanning the range between the extent of a protein complex and the resolution limit of optical microscopy.

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We have designed and synthesized a new functional (amino reactive) highly efficient fluorescent molecular switch (FMS) with a photochromic diarylethene and a rhodamine fluorescent dye. The reactive group in this FMS -N-hydroxysuccinimide ester- allows selective labeling of amino containing molecules or other materials. In ethanolic solutions, the compound displays a large fluorescent quantum yield of 52 % and a large fluorescence modulation ratio (94 %) between two states that may be interconverted with red and near-UV light.

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The study examined the cultural context of psychological illness among elder immigrants from the former Soviet Union (FSU). Kleinman's (1980) explanatory model of illness and Leininger's theory of culture care (1997) provided the conceptual framework for the study. Participant Observations were conducted in an Adult Day Care Center and Senior Housing.

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