516 results match your criteria: "V.N. Karazin Kharkiv National University[Affiliation]"

Objective: The aim: To investigate the epidemiological and clinical characteristics of COVID-19 in children for the period 2020-2022.

Patients And Methods: Materials and methods: A retrospective analysis of 1144 case histories of children who were hospitalized at the St. Zinaida Children's Clinical Hospital (Sumy, Ukraine) for coronavirus disease for 2020-2022 was carried out.

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Objective: The aim: To investigate the clinical characteristics of EBV infection in the pediatric nervous system using laboratory methods and brain MRI data.

Patients And Methods: Materials and methods: We observed 41 children with EBV encephalitis ranging from 8 months to 17 years old. The diagnosis of EBV-encephalitis was established on the basis of clinical and medical history, laboratory and instrumental (brain MRI) data.

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An efficient protocol for the synthesis of novel methotrexate-betulonic acid hybrids with a (tert-butoxycarbonylamino)-3,6-dioxa-8-octanamine (Boc-DOOA) linkage has been developed. Reaction of N-(2-(2-(2-aminoethoxy)ethoxy)ethyl)-betulonamide with methotrexate resulted in a mixture of isomeric conjugates which were separated by column chromatography. Their structures and composition have been fully established by H NMR, C spectra, FAB mass spectrometry and elemental analysis.

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Crystal structure of 2-methyl-1-imidazol-3-ium 3,5-di-carb-oxy-benzoate.

Acta Crystallogr E Crystallogr Commun

November 2023

Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany.

The structure of the title salt, CHN ·CHO (), is reported. The compound is built from a protonated 2-methyl-imidazole and a singly deprotonated trimesic acid. Detailed analysis of bond distances and angles for both ions reveals subtle differences compared with their neutral mol-ecule counterpart.

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In the last 10 years the interest in deep eutectic solvents (DESs) as a new class of green solvents has considerably increased. The emergence of numerous of hydrophobic DESs has stimulated intensive research into their application in extraction technologies, including sample preparation. As the properties of such systems are highly dependent on the properties of their components (hydrogen bond donors and acceptors) and can be finely tuned, DESs can be successfully used for the extraction of both metal ions and organic substances, including biomolecules.

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For the first time, a complete all-atom molecular dynamics (MD) model of a virus, bacteriophage MS2, in its entirety, including a protein outer shell, native genomic RNA with necessary divalent ions, and surrounding explicit aqueous solution with ions at physiological concentration, was built. The model is based on an experimentally measured cryo-EM structure, which was substantially augmented by reconstructing missing or low-resolution parts of the measured density (where the atomistic structure cannot be fit unambiguously). The model was tested by a quarter of a microsecond MD run, and various biophysical characteristics are obtained and analyzed.

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Trilogy of Fallot (ToF) is a rare congenital heart disease characterized by a combination of atrial septal defect, pulmonary stenosis, and right ventricular hypertrophy. It is more common in females and can cause symptoms such as cyanosis and breathlessness. ToF can lead to complications like thromboembolic events, including infective endocarditis (IE) and cerebral venous thrombosis (CVT).

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Work objective - to study the relationship between the duration of remission after the onset, the severity of relapses against the background of different duration of the relapsing stage (RS) and the nature of the prognosis in the secondary progressive multiple sclerosis (SPMS) using clinical and mathematical analysis. Patients with different prognosis for SPMS; neurological examination using The Expanded Disability Status Scale (EDSS); a survey method. Mathematical methods: 'contingency tables 2x2' (determining the significance of the connection between a pair of two indicators - different duration of remission after the onset and RS in four groups of patients), Yule's Coefficient of Association (determining the magnitude of differences between the group and the studied indicator), a permutation test (defining clinical indicators on RS, which significantly differed in mild and severe relapses).

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The review compiles information on the spectral classification of flavonoids, the changes in their electronic structure upon complex formation, and the manifestation of these changes in the absorption and emission spectra. Part of the review is devoted to the regioselectivity of the complex formation process, including types of complexation sites, the structure of chelates and 'open' complexes, and the correlation between the structure of complexes and their spectral properties. The interplay between complex formation and other processes occurring in flavonoids during electronic excitation is also considered, such as intramolecular inter-fragment charge transfer (ICT) and intramolecular proton transfer (ESIPT).

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Objective: The aim: Study of the levels of leptin and the growth modulator TGF-β1 in the blood serum of patients with hypertension, which occurs on the background of AO and without it.

Patients And Methods: Materials and methods: Carbohydrate metabolism was studied by the enzymatic method, the level of insulin in the blood (by the enzyme immunoassay method), the oral glucose tolerance test and the calculation of the NOMA index.

Results: Results: The data obtained in the work indicate a significant role of leptin in the formation of hypertension itself and the development of obesity, carbohydrate and lipid metabolism disorders.

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Objective: The aim: To study the activity of inducible NO synthase in the blood, the content of NO metabolites and peroxynitrite in the skin and blood of guinea pigs during erythema periods after local ultraviolet skin irradiation.

Patients And Methods: Materials and methods: The studies were carried out on 24 guinea pigs, subjected to local ultraviolet irradiation. The control group consisted of intact guinea pigs (n=6).

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Fluorescent Probes and Quenchers in Studies of Protein Folding and Protein-Lipid Interactions.

Chem Rec

February 2024

Department of Biochemistry and Molecular Biology, The University of Kansas Medical Center, 3901 Rainbow Boulevard, Kansas City, KS, 66160, United States.

Fluorescence spectroscopy provides numerous methodological tools for structural and functional studies of biological macromolecules and their complexes. All fluorescence-based approaches require either existence of an intrinsic probe or an introduction of an extrinsic one. Moreover, studies of complex systems often require an additional introduction of a specific quencher molecule acting in combination with a fluorophore to provide structural or thermodynamic information.

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Our study aimed to examine whether there are differences in the proliferation trend of microsporidia in mosquito larvae of the same genus (Culex spp.). DNA-barcoding and quantitative analyses were used to determine microsporidian rDNA copies in 'early' (L1 + L2) and 'late' (L3 + L4) Culex larvae in a natural population.

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Dihydroazolopyrimidines are an important class of heterocycles that are isosteric to natural purines and are therefore of great interest primarily as drug-like molecules. In contrast to the heteroaromatic analogs, synthetic approaches to these compounds were developed much later, and their chemical properties and biological activity have not been studied in detail until recently. In the review, different ways to build dihydroazolopyrimidine systems from different building blocks are described - via the initial formation of a partially hydrogenated pyrimidine ring or an azole ring, as well as a one-pot assembly of azole and azine fragments.

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A post-thyroidectomy hematoma is a rare, potentially fatal surgical complication that may present as hoarseness, dysphagia, and difficulty in breathing, which could progress to complete airway obstruction and, ultimately, death. The treatment for a neck hematoma is emergent surgical drainage. While certain precautions can be taken to prevent this complication, such as the cessation of any anticoagulants prior to surgery, it is still a feared complication of thyroidectomy with an increasing prevalence.

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Background: Telomerase reverse transcriptase (TERT) plays a crucial role in synthesizing telomeric repeats that safeguard chromosomes from damage and fusion, thereby maintaining genome stability. Mutations in the TERT gene can lead to a deviation in gene expression, impaired enzyme activity, and, as a result, abnormal telomere shortening. Genetic markers of productivity traits in livestock can be developed based on the TERT gene polymorphism for use in marker-associated selection (MAS).

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We assessed the diversity and composition of fungal communities in different functional tissues and the rhizosphere soil of and stands along the latitudinal gradient of these tree species distributions in Europe to model possible changes in fungal communities imposed by climate change. For each tree species, living needles, shoots, roots, and the rhizosphere soil were sampled and subjected to high-throughput sequencing. Results showed that the latitude and the host tree species had a limited effect on the diversity and composition of fungal communities, which were largely explained by the environmental variables of each site and the substrate they colonize.

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We consider the impact of strong biological correlations on the epidemic process. The biological correlations mean the influence of the environment on the individual state of immunity of the infected person. Accounting for the correlations turns the traditional SIRS model into the 3D Lotka-Volterra model, the parameters of which are uniquely determined by the parameters of the original SIRS model.

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The high mutation rate of SARS-CoV-2, which has led to the emergence of a number of virus variants, creates risks of transmission from humans to animal species and the emergence of new animal reservoirs of COVID-19. This study aimed to identify animal species among livestock susceptible to infection and develop an approach that would be possible to use for assessing the hazards caused by new SARS-CoV-2 variants for animals. Bioinformatic analysis was used to evaluate the ability of receptor-binding domains (RBDs) of different SARS-CoV-2 variants to interact with ACE2 receptors of livestock species.

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Protonation of key histidine residues has been long implicated in the acid-mediated cellular action of the diphtheria toxin translocation (T-) domain, responsible for the delivery of the catalytic domain into the cell. Here, we use a combination of computational (constant-pH Molecular Dynamics simulations) and experimental (NMR, circular dichroism, and fluorescence spectroscopy along with the X-ray crystallography) approaches to characterize the initial stages of conformational change happening in solution in the wild-type T-domain and in the H223Q/H257Q double mutant. This replacement suppresses the acid-induced transition, resulting in the retention of a more stable protein structure in solutions at pH 5.

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Despite previous studies, understanding the fundamental mechanism of melting metal nanoparticles remains one of the major scientific challenges of nanoscience. Herein, the kinetics of melting of a single Sn nanoparticle was investigated using transmission electron microscopy heating techniques with a temperature step of up to 0.5 °C.

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Background: Herein, we describe a new species of turtle blood-feeding leech, Placobdella nabeulensis sp. nov. from Palearctic North Africa (Tunisia and Algeria).

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Tuberculosis: current challenges and beyond.

Breathe (Sheff)

March 2023

Centre for Multidisciplinary Research in Health Science, University of Milan, Milan, Italy.

Despite being a preventable and curable disease, tuberculosis (TB) is still a major global health threat and the second leading cause of death due to an infectious agent worldwide. All the efforts invested to end TB have resulted overall in rather slow decreases in TB incidence and mortality rates, which have been further negatively affected by the ongoing coronavirus disease 2019 (COVID-19) pandemic. While the majority of targets of the End TB Strategy remain off track, and we have not yet overcome the disruptions caused by the COVID-19 pandemic, recent conflicts such as the ongoing war in Ukraine are threatening the decrease of the burden of TB even further.

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We explore the rich nature of correlations in the ground state of ultracold atoms trapped in state-dependent optical lattices. In particular, we consider interacting fermionic ytterbium or strontium atoms, realizing a two-orbital Hubbard model with two spin components. We analyze the model in one-dimensional setting with the experimentally relevant hierarchy of tunneling and interaction amplitudes by means of exact diagonalization and matrix product states approaches, and study the correlation functions in density, spin, and orbital sectors as functions of variable densities of atoms in the ground and metastable excited states.

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Objective: The aim: To clarify the frequency with which various variants of the formation and course of drug-resistant epilepsy occur in children with genetic polymor¬phisms of cytochromes CYP2C9, CYP2C19, CYP3A4.

Patients And Methods: Materials and methods: The genotyping of CYP2C9*2, CYP2C9*3, CYP2C19*2, CYP3A4*1B by the allele-specific polymerase chain reaction was performed in 116 children with drug-resistant epilepsy aged from 2 to 17 years. Thirty cases (boys-15; girls-15) with a follow-up period of more than 5 years were analyzed in detail.

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