Sulfonated Hydroxyaryl-Tetrazines with Increased pK for Accelerated Bioorthogonal Click-to-Release Reactions in Cells.

Bioorthogonal reactions that enable switching molecular functions by breaking chemical bonds have gained prominence, with the tetrazine-mediated cleavage of trans-cyclooctene caged compounds (click-to-release) being particularly noteworthy for its high versatility, biocompatibility, and fast reaction rates. Despite several recent advances, the development of highly reactive tetrazines enabling quantitative elimination from trans-cyclooctene linkers remains challenging. In this study, we present the synthesis and application of sulfo-tetrazines, a class of derivatives featuring phenolic hydroxyl groups with increased acidity constants (pK).

The Hydrogen-Bond Continuum in the Salt/Cocrystal Systems of Quinoline and Chloro-Nitrobenzoic Acids.

This study investigates the hydrogen-bond geometry in six two-component solid systems composed of quinoline and chloro-nitrobenzoic acids. New X-ray diffraction studies were conducted using both the conventional independent-atom model and the more recent Hirshfeld atom-refinement method, with the latter providing precise hydrogen-atom positions. The systems can be divided into salts (the hydrogen atom transferred to the quinoline nitrogen), cocrystals (the hydrogen atom retained by the acid), and intermediate structures.

[Experience of using eculizumab in refractory myasthenia gravis].

Myasthenia gravis (MG) is a chronic autoimmune disease mediated by autoreactive T- and B-cells and manifested by progressive pathological muscle weakness and fatigue. Traditional immunomodulatory treatment does not always lead to the clinical picture significant improvement, despite adequate dosage and duration of use. Refractory myasthenia gravis requires new therapeutic approaches development and implementation.

Determination of physicochemical parameters of (bio)molecules and (bio)particles by capillary electromigration methods.

The review provides an overview of recent developments and applications of capillary electromigration (CE) methods for the determination of important physicochemical parameters of various (bio)molecules and (bio)particles. These parameters include actual and limiting (absolute) ionic mobilities, effective electrophoretic mobilities, effective charges, isoelectric points, electrokinetic potentials, hydrodynamic radii, diffusion coefficients, relative molecular masses, acidity (ionization) constants, binding constants and stoichiometry of (bio)molecular complexes, changes of Gibbs free energy, enthalpy and entropy and rate constants of chemical reactions and interactions, retention factors and partition and distribution coefficients. For the determination of these parameters, the following CE methods are employed: zone electrophoresis in a free solution or in sieving media, isotachophoresis, isoelectric focusing, affinity electrophoresis, electrokinetic chromatography, and electrochromatography.

The separation of cyclic diadenosine diphosphorothioate and the diastereomers of its difluorinated derivative and the estimation of the binding constants and ionic mobilities of their complexes with 2-hydroxypropyl-β-cyclodextrin by affinity capillary electrophoresis.

The incorporation of phosphorothioate linkages has recently been extensively employed in therapeutic oligonucleotides. For their separation and quality control, new high-efficient and high-sensitive analytical methods are needed. In this work, a new affinity capillary electrophoresis method has been developed and applied for the separation of a potential anticancer drug, 2',3'-cyclic diadenosine diphosphorothioate (R, R) (ADU-S100), and three recently newly synthesized diastereomers of its difluorinated derivative, 3',3'-cyclic di(2'-fluoro, 2'-deoxyadenosine phosphorothioate).

Acidity constants and protonation sites of cyclic dinucleotides determined by capillary electrophoresis, quantum chemical calculations, and NMR spectroscopy.

Cyclic dinucleotides (CDNs) are important second messengers in bacteria and eukaryotes. Detailed characterization of their physicochemical properties is a prerequisite for understanding their biological functions. Herein, we examine acid-base and electromigration properties of selected CDNs employing capillary electrophoresis (CE), density functional theory (DFT), and nuclear magnetic resonance (NMR) spectroscopy to provide benchmark pK values, as well as to unambiguously determine the protonation sites.

[Possibilities of optimizing therapy in COVID-19 survivors with focal epilepsy].

Objective: To study the effect of phenosanoic acid therapy on the frequency of seizures, asthenia and quality of life of adult patients with focal epilepsy who had a new coronavirus infection caused by SARS-CoV-2.

Material And Methods: The data of 20 patients with focal epilepsy who suffered COVID-19 and received therapy with phenosanic acid (Dibufelon) were studied. The frequency of epileptic seizures, the severity of asthenia and the quality of life were evaluated according to clinical scales.

Recent developments and applications of capillary and microchip electrophoresis in proteomics and peptidomics (mid-2018-2022).

This review gives a wide overview of recent advances and applications of capillary electrophoresis and microchip capillary electrophoresis methods in the fields of proteomics and peptidomics in the period from mid-2018 up to the end of 2022. The methodological topics covering sample preparation and concentration techniques, hyphenation of capillary electrophoresis methods with mass spectrometry, and multidimensional separations by on-line or off-line coupled different capillary electrophoresis and liquid chromatography techniques are described and new developments in both bottom-up and top-down approaches in proteomics are presented. In addition, various applications of capillary electrophoresis methods in proteomic and peptidomic studies are demonstrated.

Bis(oxiranes) Containing Cyclooctane Core: Synthesis and Reactivity towards NaN.

Reactions of oxirane ring opening provide a powerful tool for regio- and stereoselective synthesis of polyfunctional and heterocyclic compounds, widely used in organic chemistry and drug design. Cyclooctane, alongside other medium-sized rings, is of interest as a novel molecular platform for the construction of target-oriented leads. Additionally, cyclooctane derivatives are well known to be prone to transannular reactions, which makes them a promising object in the search for novel approaches to polycyclic structures.

Cross-syndrome: myasthenia gravis and the demyelinating diseases of the central nervous system combination. Systematic literature review and case reports.

Nowadays the problem of comorbidity is still relevant. In this review, we describe clinical cases of the disease of the neuromuscular junction (myasthenia gravis (MG) generalized form) and the demyelinating disease of the central nervous system (DD CNS) (multiple sclerosis, neuromyelitis optica spectrum disorder (NMOSD), etc.) combinations registered in our practice with precise pathogenetic analysis.

Applications of capillary electromigration methods for separation and analysis of proteins (2017-mid 2021) - A review.

This paper provides a detailed overview of relevant developments in separation and analysis of proteins by capillary electromigration (CE) methods in the period 2017-mid 2021. The presented topics embrace sample preparation, suppression of protein sorption, control of electroosmotic flow, separations of proteins by the particular CE methods and protein identification and quantification by various detection techniques. To illustrate the wide usability of CE methods for protein analysis, the paper shows several novel applications of CE methods, such as quality control and characterization of protein biopharmaceuticals, determination of proteins in complex biomatrices, investigation of posttranslational modification, peptide mapping, interactions of proteins with other (bio)molecules and determination of their physicochemical and biochemical characteristics.

[Determination of the prevalence of postcovid syndrome and assessment of the effectiveness of the drug Cortexin in the treatment of neurological disorders in patients with postcovid syndrome. Results of the multicenter clinical and epidemiological observational program CORTEX].

Objective: To study the prevalence of clinical manifestations of postcoid syndrome in patients at an outpatient neurological appointment, to evaluate the effectiveness of therapy regimens using Cortexin at doses of 10 mg and 20 mg IM for 10 days.

Materials And Methods: 674 neurologists from all regions of the Russian Federation, Azerbaijan, Kyrgyzstan and Kazakhstan took part in the study. A total of 979 COVID-19 patients were recruited.

Nonaqueous capillary electrophoresis and quantum chemical calculations applied to investigation of acid-base and electromigration properties of azahelicenes.

Nonaqueous capillary electrophoresis (NACE) using methanol (MeOH) as a solvent of the BGEs and quantum mechanical density functional theory (DFT) have been applied to determine the thermodynamic acidity (ionization) constants (pK ) of mono- and diaza[5]helicenes, mono- and diaza[6]helicenes, and their dibenzo derivatives in MeOH and water. First, the mixed acidity constants, , of ionogenic pyridinium groups of azahelicenes and their derivatives in MeOH were obtained by nonlinear regression analysis of pH dependence of their effective electrophoretic mobilities. The effective mobilities were measured by NACE in a large series of methanolic BGEs within a wide conventional pH range (pH 1.

Diagnostic value of microbiome biomarkers of the periodonite microbiome in patients with the association of chronic periodontitis and diabetes mellitus type 2.

The place of high-tech methods of molecular biology in clinical laboratory diagnostics of various diseases and the development of a system of biomarkers as an important component of diagnostic research is currently attracting the closest attention of the scientific community. In this paper, an attempt is made to use high-tech metagenomic analysis to solve problems that arise due to the high frequency of association of periodontal diseases with systemic pathology, in particular, with type 2 diabetes mellitus. The aim of the study was to determine the taxonomic and metabolic features of the microbiome of periodontal tissues in periodontal diseases associated with type 2 diabetes mellitus, as a model of the ratio of local and systemic effects of periodontal pathogenic bacteria.

Peptidomics and Capillary Electrophoresis.

Peptides play a crucial role in many vitally important functions of living organisms. The goal of peptidomics is the identification of the "peptidome," the whole peptide content of a cell, organ, tissue, body fluid, or organism. In peptidomic or proteomic studies, capillary electrophoresis (CE) is an alternative technique for liquid chromatography.

Phenolic acids and antioxidant potential of Caragana frutex shoots.

The phenolic acid composition of flowering Caragana frutex shoots was analyzed by the HPLC method. The quantitative content of seven phenolic acids and their derivatives has been determined: gallic, p-hydroxyphenyl acetic, chlorogenic, caffeic, р-coumaric, trans-ferulic, and sinapic) acids. Sinapic acid (513.

[Acupuncture in the prevention and treatment of stroke: a review of foreign studies].

Acupuncture has been recommended by the World Health Organization (WHO) as an alternative and complementary method for treating stroke and a way to increase the effectiveness of rehabilitation. The data available in the literature suggest that acupuncture has a beneficial effect on the status of patients with stroke. The mechanism of action of acupuncture for stroke includes the following components: 1) stimulation of neurogenesis and cell proliferation in the CNS; 2) regulation of cerebral blood flow; 3) antiapoptosis; 4) regulation of neurotransmitters; 5) improvement of the neuronal synaptic function, stimulation of long-term potentiation; 6) stimulation of neuroplasticity; and 7) decrease in blood-brain barrier permeability.

[The methodology of complex social hygienic investigation of various groups of population and families (In memoriam of professor O. V. Grinina)].

The article expounds main principal positions of professor O. V. Grinina scientific educational methodological school of social hygienic investigations of health of population and family.

Copper-Promoted C-Se Cross-Coupling of 2-Selenohydantoins with Arylboronic Acids in an Open Flask.

The modification of Chan-Lam-Evans cross-coupling reaction for the selective Se-arylation of 2-selenohydantoins under base-free mild conditions via aryl boronic acids is described herein. This approach was used to synthesize novel 5-arylidene-3-substituted-2-(arylselanyl)-imidazoline-4-ones with high yields. The anticancer activity of the final compounds was evaluated in vitro against different cancer cells, and thus, the possibility of 5-arylidene-3-substituted-2-(arylselanyl)-imidazoline-4-ones successful application as cytotoxic agents was demonstrated.

[Clinical and molecular-genetic characteristics of X-linked spinal-bulbar amyotrophy (Kennedy's disease) in the Sakha Republic (Yakutia)].

Aim: To perform a clinical-genealogical and molecular genetic analysis of X-linked spinal-bulbar amyotrophy (Kennedy's disease) in the Sakha Republic (Yakutia).

Material And Methods: Six patients, aged from 30 to 60 years, from 4 unrelated Yakut families registered in the Republican genetics registry of hereditary and congenital abnormalities of the Sakha Republic were studied. The average age of onset was 45.

Dataset of phytoplankton productive parameters and environmental forces in autumn in the Kara Sea.

This data article contains data on the photosynthetic activity, shares of the main algae groups in the total phytoplankton biomass and the main environmental forces in the Kara Sea. The data were collected from 17 to 29 of September, 2011 in the following different areas: the Kara Sea Shelf with and without river runoff influence, the shelf edge and continental slope. The photosynthetic activity parameters include the relative electron transport rate (rETR) values, the maximum quantum efficiency of PSII (Fv/Fm) and the P/rETR ratio as photosynthetic performance.

Recent developments and applications of capillary and microchip electrophoresis in proteomics and peptidomics (2015-mid 2018).

This review summarizes recent developments and applications of capillary and microchip electroseparation methods in proteomic and peptidomic analyses since the year 2015 to ca. mid 2018. Sample preparation procedures for the removal of interfering components or for pre-fractionation and preconcentration of proteins and peptides of interest are discussed.

Separation of rotamers of 5-nitrosopyrimidines and estimation of binding constants of their complexes with β-cyclodextrin by capillary electrophoresis.

For the first time, capillary electrophoresis has been successfully employed for the fast and highly efficient separations of a novel type of stereoisomers - planar rotamers (planamers) of four newly synthesized 5-nitrosopyrimidine derivatives. These derivatives can form two rotamers differing in the orientation of nitroso group due to strong intramolecular hydrogen bonds. Partial separation of rotamers of two 5-nitrosopyrimidines was achieved in alkaline 50 mM sodium tetraborate, pH 9.

Analysis of proteins and peptides by electromigration methods in microchips.

This review presents the developments and applications of microchip electromigration methods in the separation and analysis of peptides and proteins in the period 2011-mid-2016. The developments in sample preparation and preconcentration, microchannel material, and surface treatment are described. Separations by various microchip electromigration methods (zone electrophoresis in free and sieving media, affinity electrophoresis, isotachophoresis, isoelectric focusing, electrokinetic chromatography, and electrochromatography) are demonstrated.