Helicity-dependent resonant X-ray scattering in CuB2O4.

Exploitation of X-ray circular polarized beams to study forbidden Bragg reflections and new information that could be obtained in these experiments are discussed. It is shown that the intensities of such reflections can be different for the right- and left-circular polarizations (i.e. exhibiting circular dichroism) even for the dipole-dipole resonant transitions involved in the scattering process. This difference can be observed only in crystals having no center of inversion. Here, this approach is used to study helicity-dependent resonant diffraction in copper metaborate CuB2O4 single crystal, which is non-centrosymmetric but achiral. Nonetheless, a strong circular dichroism has been observed for hh0 forbidden reflections in the vicinity of the Cu K-edge. This effect is shown to originate from dipolar transitions in Cu atoms occupying the 8(d) Wyckoff position only.

Genetic analysis of genotype G57 H9N2 avian influenza virus isolate A/chicken/Tajikistan/2379/2018 recovered in Central Asia.

This paper presents genetic data on the full genome analysis of A/chicken/Tajikistan/2379/2018 H9N2 influenza virus isolated in September 2018 from chicken pathological material received from poultry farms of the Republic of Tajikistan and subtyped as H9N2 by serological and molecular methods. According to the results of hemagglutinin gene sequencing, the amino acid sequence of the cleavage site was RSSR/GLF, which is typical for low-virulent avian influenza virus. Phylogenetic analysis of the nucleotide sequence of a hemagglutinin gene fragment (nt 1-1539 of the open reading frame) showed that the A/chicken/Tajikistan/2379/2018 H9N2 isolate belongs to the Y280 genetic group of low-virulent A/H9 influenza virus, which is widespread in Southeast Asia. The complete nucleotide sequence of the viral genome was determined. Comparative analysis of all genomic segments revealed that the A/chicken/Tajikistan/2379/2018 H9N2 virus is closely related to an A/H9 influenza virus isolated in the Far East of the Russian Federation in 2018. Genetic similarity (97.1-99% identity in four out of eight viral genes) was found to isolates of an H7N9 subtype virus recovered in the Inner Mongolia and Hebei regions of China in 2017. According to the analysis of the predicted amino acid sequence of the studied isolate, the positions of some molecular markers indicate possible adaptation of the virus to mammals. Further genetic analysis showed that this virus belongs to genotype G57.

A Sorbent with Synthetic Ligand for Removing Pro-atherogenic and Pro-inflammatory Components from Human Blood Plasma.

Elevated levels of apoB-100 containing lipoproteins and markers of systemic inflammation are often observed in patients with cardiovascular diseases. The concentrations can be reduced by pharmacotherapy or extracorporeal treatment. The sorbent, which removes CRP and atherogenic lipoproteins, simultaneously reduces the bloodstream concentration of these components. The efficacy and selectivity of the designed sorbent were studied, desorption constants of CRP (Kd = 4.2 × 10-8 M) and LDL (Kd = 7.7 × 10-7 M) were distribution coefficients of CRP (Kc = 101) and Lp(a) (Kc = 38) were calculated, and the ability to bind large amounts of atherogenic lipoproteins (up to 32 mg of TC per mL of the sorbent gel) was demonstrated. Our sorbent can be recommended for performing complex removal of CRP and atherogenic lipoproteins from the blood plasma in patients with refractory hyperlipidemia and CVD that are accompanied by elevated levels of CRP.

Chronic hyponatremia in the elderly: association with geriatric syndromes (review of literature).

Hyponatremia is more common in the elderly. A number of studies suggest that even mild chronic hyponatremia is a serious danger, increasing the risks of developing geriatric syndromes, falls, low bone density, fractures, cognitive impairment, and death of all causes. Although the mechanism for the development of such complications is currently not completely clear. Questions remain about the need and methods for correcting this condition, although there is some evidence that the correction of hyponatremia improves cognitive functions, postural balance, minimizing the risk of falls and fractures. These issues are addressed in this review of the literature.

[Low concentrations of hepatitis C virus RNA in serologically mild infection.]

Occult HCV infection (OCI) provides significant interest recently. HCV RNA in this case can be detected not in plasma, but in blood cells and/or in liver tissue. In case of antibody genesis impairment anti-HCV detection may lead to negative or "uncertain" result. The aim of the study was to estimate infection type in blood donors and patients with hematological diseases by exploration of samples with uncertain anti-HCV detection results. Blood samples of 30 180 potential blood donors' and 4322 patients with hematological diseases were tested. Comparative analysis of wide pattern of HCV markers was performed. 33 blood donors and 42 patients were enrolled in follow-up examination. Uncertain results of Anti-HCV detection in donors' samples were in 0.18% of cases. Follow-up examination of 33 donors provided discordant results using immunochemiluminescence assay and ELISA. 15.2% donors' samples contained HCV RNA in low concentration. Follow-up observation of 42 patients with incomplete antiviral antibody pattern showed HCV RNA presence in 40.5% cases (21.4% high viremia and 19.0% low viremia). Samples with low RNA concentration contained low titers of anti-core antibodies. Samples with high titers of anti-core antibodies contained high HCV RNA level. Uncertain results of anti-HCV in 15.2% of potential blood donors' samples were confirmed by detection of HCV RNA in low concentration. It proved OCI presence in these individuals and called for testing for wide pattern of HCV markers in addition to routine screening. Patients with hematological diseases showed low level of HCV RNA along with low titers of antibodies against one or two viral antigens.

New Sorbent on the Basis of Covalently Immobilized Lysozyme for Removal of Bacterial Lipopolysaccharide (Endotoxin) from Biological Fluids.

It was demonstrated for the first time that immobilized lysozyme can efficiently remove Escherichia coli and Pseudomonas aeruginosa lipopolysaccharides (endotoxins) from solutions. Experimentally confirmed sorption capacity for the developed sorbent was at least 400 ng of endotoxin per ml sorbent. The new sorbent is compatible with the whole human blood and can be potentially used in extracorporeal therapy in the treatment of sepsis.

[Impact of current approaches to laboratory screening of donated blood and its components on hepatitis B virus infection in patients with blood system diseases]. / Vliianie sovremennykh podkhodov k laboratornomu obsledovaniiu donorov krovi i ee komponentov na infitsirovannost' virusom gepatita V u bol'nykh s zabolevaniiami sistemy krovi.

AIM: To evaluate the detection rate of markers for hepatitis B virus (HBV) in the blood samples taken from patients with blood system diseases, by applying the current approaches to examining donated blood and its components for markers of viral infections. MATERIAL AND METHODS: The investigation included blood samples from patients with blood system diseases (n=364) and donors (n=5,011). The results of laboratory screening of donated blood samples (n=13,081) were retrospectively analyzed. Commercial kits of reagents were used for immunochemical assay and polymerase chain reaction. RESULTS: Patients with blood system diseases were recorded to have markers of active HBV infection in 12.6% of cases, anti-HBc in 31.3%, and anti-HBs in 37.6%. A retrospective analysis of the results of screening donated blood samples showed the presence of markers for active HBV infection in 0.28% of cases. A prospective examination of blood donors revealed markers of HBV infection in 4.83% of cases, including those of active forms in 0.54% and anti-HBc in 4.79%. The markers of active HBV infection in donors were only anti-HBc IgM in 0.42% of cases. The blood samples from donors with an anti-HBs titer of >200 mIU/ml contained anti-HBc IgM in 10.5%. CONCLUSION: In the last 5-7 years, the detection rate of markers of HBV infection in the blood samples of patients with blood system diseases have remained at a high level. Screening for decreed markers fails to identify people with inapparent infections among the donors. Even high anti-HBs concentrations in the donated blood may be a risk for HBV transmission by transfusion to a recipient.

Band Filling Control of the Dzyaloshinskii-Moriya Interaction in Weakly Ferromagnetic Insulators.

We observe and explain theoretically a dramatic evolution of the Dzyaloshinskii-Moriya interaction (DMI) in the series of isostructural weak ferromagnets, MnCO_{3}, FeBO_{3}, CoCO_{3}, and NiCO_{3}. The sign of the interaction is encoded in the phase of the x-ray magnetic diffraction amplitude, observed through interference with resonant quadrupole scattering. We find very good quantitative agreement with first-principles electronic structure calculations, reproducing both sign and magnitude through the series, and propose a simplified "toy model" to explain the change in sign with 3d shell filling. The model gives insight into the evolution of the DMI in Mott and charge transfer insulators.

Bacteriolytic Activity Of Human Interleukin-2, Chicken Egg Lysozyme In The Presence Of Potential Effectors.

The bacteriolytic activity of interleukin-2 and chicken egg lysozyme in the presence of various substances has been studied. Glycine and lysine do not affect the activity of interleukin-2 but increase that of lysozyme, showing a bell-shape concentration dependence peaking at 1.5 mM glycine and 18 mM lysine. Arginine and glutamate activate both interleukin-2 and lysozyme with a concentration dependence of the saturation type. Aromatic amino acids have almost no effect on the activity of both interleukin-2 and lysozyme. Aromatic amines, tryptamine, and tyramine activate interleukin-2 but inhibit lysozyme. Peptide antibiotics affect interleukin and lysozyme similarly and exhibit maximum activity in the micromolar range of antibiotics. Taurine has no effect on the activity of interleukin-2 and lysozyme. Mildronate showed no influence on lysozyme, but it activated interleukin-2 with the activity maximum at 3 mM. EDTA activates both interleukin-2 and lysozyme at concentrations above 0.15 mM.

Human Interleukin-2 and Hen Egg White Lysozyme: Screening for Bacteriolytic Activity against Various Bacterial Cells.

The bacteriolytic activity of interleukin-2 and hen egg white lysozyme against 34 different species of microorganisms has been studied. It was found that 6 species of microorganisms are lysed in the presence of interleukin-2. All interleukin-2-sensitive microorganisms belong either to the Enterobacteriaceae, Bacillaceae, or the Lactobacillaceae family. It was also found that 12 species of microorganisms are lysed in the presence of lysozyme, and 16 species of microorganisms are lysed in the presence of sodium dodecyl sulfate (SDS). The bacteriolytic activity of interleukin-2 and lysozyme was studied at various pH values.

[The screening of donor blood on antibodies to nuclear antigen of hepatitis B virus as a tool of increasing of safety of transfusion for patients with diseases of blood system.]

Despite application of decreed modes of laboratory analysis of components of donors' blood, the risk of infection of recipients with hepatitis B virus continues to be actual. The isolated identification of HBsAg provides no control of all categories of persons infected with hepatitis B virus. The analysis of presence of antibodies to nuclear antigen of hepatitis B virus that are the first out of antiviral ones and are preserved for life, is an expedient technique of screening testing of donor's blood that permits implementing an additional selection of donors. During March 2014 - March 2015, cohort of regular anti-hepatitis B virus negative donors of blood and its components. The testing of blood samples for anti-hepatitis B virus can be recommended as a routine test increasing viral safety of blood transfusions for patients with diseases of blood system.

[Tyramine and tryptamine as ligands for medical and biotechnological affinity sorbents].

A novel technique for preparation affinity sorbent based on tyramine and tryptamine was proposed. It was shown that tryptamine-Sepharose and tyramine-Sepharose effectively bind IgG, IgA, lipoprotein (a) (Lp(a)) and low density lipoproteins (LDL) from blood plasma. The sorption capacity is 4-9 mg of IgG, 2-4 mg IgA, 3-5:mg of Lp(a) and 5-7 mg of LDL per mL of gel. It was found that new sorbents can bind Lp(a) and IgG as themselves or in a complex of Lp(a) with IgG. The existence of this complex may indicate the presence of anti-Lp(a) autoantibodies in the blood of some patients. The advantages of new sorbents are easiness of its synthesis and stability during use and storage. In practice they can be applied for medical and biotechnological purposes where it is necessary to bind Lp(a), LDL, IgG, IgA.

[Affine Haemosorbents Based on Aromatic Peptides for Binding of the Immunoglobulin G].

Affinity haemoadsorbents based on WY, WTY, WNY ligands and polysaccharide matrix were developed for the human immunoglobulin G binding. The characteristics of new sorbents such as the binding of total IgG and binding of IgG subclasses were compared. It was found that all new sorbents well extract the IgG from the blood plasma. It was evidenced that WNY-based sorbent is more effective for binding of IgG subclass 3. The determination of physic-chemical characteristics of IgG binding revealed that desorption constants for IgG are 10 ± 3, 28 ± 4 and 13 ± 3 µM for WY, WTY, WNY based sorbents respectively. Maximum sorption capacities for IgG are 43 ± 2, 45 ± 3 and 46 ± 3 mg IgG per ml of sorbent for WY, WTY, WNY based sorbents respectively. Also it was shown that the new sorbents are compatible with blood and are suitable for the medical purposes.

[Non-convulsive status epilepticus with a phenomenon of transitory amnesia].

This article describes clinical cases of 13 year old boy with two non-convulsive status epilepticus which had transient epileptic amnesia as a clinical implication. Status EEG pattern in form of diffuse epileptic activity "benign epileptiform discharge of childhood" type was registered.

[DNA aptamer based sorbents for binding human IgE].

DNA aptamer based sorbents are synthesized for binding human IgE. Sorbents effectively removed IgE from human blood plasma. The experimental values of IgE desorption constants were from 11 x 10(-l0) to 1.7 x 10(-10) M depending on the orientation of the aptamer, an insoluble matrix. The sorbents were stable during multiple use. Conditions for sorbent regeneration were picked up. These chromatographic materials can be used for medical and biotechnological applications.

[Peculiarities of the surgical treatment of nasal septum perforations].

The objective of the present study was the retrospective analysis of the results of nasal septum perforation (NSP) surgery. We report our experience with the operations on the perforated nasal septum based on the treatment of a total of 84 patients. Plastic repair of the perforated nasal septum was undertaken in 54 of them. The endonasal approach with the use of local tissue flaps was employed in 47 cases. Additional bucco-gingival flaps were used in another 4 patients and the open rhinoplastic approach in 3 cases. The complete closure of nasal septum perforations was achieved in 34 (63%) patients. The reduction of the size of perforations was documented in 17 (31%) patients whereas in the remaining three the perforation size slightly increased. The surgical technique and peculiarities of the postoperative management of the patients are described; the possible causes of NSP relapses following surgery are discussed.

[Affine sorbent with typtophil-threonil-tirosine for binding immunoglobulin G: sorption characteristics and aspects of practical application].

New chromatographic material based on tryptophil-threonil-tirosine was prepared. This sorbent effectively binds human, sheep, goat and cow immunoglobulins G. New sorbent shows high selectivity for removing immunoglobulins from blood plasma. Effective sorption capacity is 15-25 mg of immunoglobulin G per ml of matrix. Optimal method of covalent attachment ligand to polysaccharide matrix allows achieving high stability of the sorbents in terms of use and storage. This sorbent can be used in medicine and biotechnology.

Ab initio calculations of the forbidden Bragg reflections energy spectra in wurtzites versus temperature.

Thermal-motion induced (TMI) scattering is caused by the influence of atomic displacements on electronic states in crystals and strongly depends on temperature. It corresponds to dipole-dipole resonant x-ray scattering, but is usually accompanied by dipole-quadrupole scattering. The phenomenological theory supposes the dipole-quadrupole term to be temperature independent (TI). As a result, the transformation of the energy spectra with temperature observed experimentally in ZnO and GaN corresponds to the interference between the TMI and TI terms. In the present paper the direct confirmation of this theoretical prediction is given. Ab initio molecular dynamics was used to simulate the sets of atomic sites at various temperatures followed by quantum mechanical calculation of resonant Bragg reflection energy spectra. The results of simulation are in excellent coincidence with experimental energy spectra of forbidden reflections and confirm the earlier phenomenological conjecture about the interference between the TI dipole-quadrupole and TMI dipole-dipole contributions to the resonant atomic factor.

Numerical simulation of the forbidden Bragg reflection spectra observed in ZnO.

Thermal motion induced (TMI) scattering is a unique probe of changes in electronic states with atomic displacements in crystals. We show that it provides a novel approach to extract atomic correlation functions. Using numerical calculations, we are able to reproduce the temperature-dependent energy spectrum of the 115 'forbidden' Bragg reflection in ZnO. Our previous experimental studies showed that the intensity growth of such reflections over a wide range of temperatures is accompanied by a dramatic change in the resonant spectral lineshape. This is the result of the interplay between the temperature-independent (TI) and temperature-dependent TMI contributions. Here, we confirm that the TI part of the resonant structure factor can be associated with the dipole-quadrupole contribution to the structure factor and show that the temperature-dependent part arises from the zinc and oxygen vibrations, which provide additional temperature-dependent dipole-dipole tensor components to the structure factor. By fitting the experimental data at various temperatures we have determined the temperature dependences of autocorrelation and correlation functions.

Interplay of inequivalent atomic positions in resonant x-ray diffraction of Fe(3)BO(6).

'Forbidden' Bragg reflections of iron orthoborate Fe(3)BO(6) were studied theoretically and experimentally in the vicinity of the iron K edge. Their energy spectra are explained as resulting from the interference of x-rays scattered from two inequivalent crystallographic sites occupied by iron ions. This particular structure property gives rise to complex azimuthal dependences of the reflection intensities in the pre-edge region as they result from the interplay of site specific dipole-quadrupole and quadrupole-quadrupole resonant scattering. Also evidenced is an anisotropic character of the absorption spectrum. Self-absorption correction to the diffraction data, as well as possible contributions of thermal vibrations and magnetic order, are discussed. Particular care is given to extracting clean spectra from the data, and it is demonstrated that excellent results can be obtained even from measurements that appear corrupted by several effects such as poor crystal quality and multiple scattering.