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Systemic scleroderma is a rare chronic disease characterized by the development of diffuse fibrosis, pathological changes in the skin, blood vessels, joints and internal organs. The article presents a clinical case of a patient with systemic scleroderma with such obvious manifestations of skin and vascular lesions as sclerodactyly, masking of the face, "purse-string mouth", Raynaud's syndrome, as well as lesions of the joints, muscles, immunological disorders, the development of steroid osteoporosis with multiple fractures

Iron(ii) and iron(iii) salts of strong acids form iron glycerolates on heating at 180 °C with glycerol in the presence of an equivalent amount of alkali. Individual iron(iii) glycerolate was obtained for the first time. When Fe3O4 magnetic nanoparticles were heated with glycerol, an iron(iii) glycerolate shell was formed on their surface. This journal is © The Royal Society of Chemistry. Ministry of Education and Science of the Russian Federation, Minobrnauka: 075-15-2020-777 The work was carried out with nancial support from the Ministry of Science and Higher Education of the Russian Federation (grant 075-15-2020-777) using the equipment of the Centre for Joint Use “Spectroscopy and Analysis of Organic Compounds” at the Postovsky Institute of Organic Synthesis of UB RAS. Mössbauer spectroscopy, XRD, and HRTEM studies were carried out within the state programs of Miheev Institute of Metal Physics of UB RAS («Function»), Institute of Solid State Chemistry of UB RAS, and Ural Federal University, correspondingly. Authors are grateful to Dr Maksim S. Karabanov (Ural Center for Shared Use “Modern Nanotechnology” at the Ural Federal University) for HRTEM study.

The high efficiency of using N-(phosphonomethyl)iminodiacetic acid (PMIDA) as a surfactant for formation of a silica coating on Fe3O4 magnetic nanoparticles (MNPs) with a large surface area has been demonstrated. The coating of PMIDA-stabilized MNPs with silica and their further APS-functionalization significantly increased the specific area (up to 203 m2 g−1) and the number of amino groups (up to 1.12 mmol/g) grafted on their surface compared to nanomaterials synthesized without preliminary SiO2-coating. The comparative study of the peptide modification efficiency, using as an example pH-low insertion peptide (pHLIP), of MNPs coated with 3-aminopropylsilane (APS) or SiO2/APS was carried out. It has been shown that silica coating of PMIDA-stabilized MNPs leads to a significant increase in the degree of immobilization of the peptide (up to 22 μmol per g of MNPs). Comprehensive characterization of the obtained materials at each stage of the synthesis was carried out using scanning electron microscopy (SEM), energy dispersive X-ray fluorescence spectroscopy (EDX), BET analysis, ATR Fourier transformed infrared spectroscopy (FTIR), termogravimetric analysis (TGA), CHN-elemental analysis, dynamic light scattering (DLS), and vibrating sample magnetometry (VSM). The proposed approach to applying SiO2-coating of MNPs can be useful for design of new materials for biomedical and chemical purposes.

Novel nanocomposite materials based on Fe3O4 magnetic nanoparticles (MNPs) coated with silica and covalently modified by [(3-triethoxysilyl)propyl]succinic acid–polyethylene glycol (PEG 3000) conjugate, which provides a high level of doxorubicin (Dox) loading, were obtained. The efficiency of Dox desorption from the surface of nanomaterials under the action of an alternating magnetic field (AMF) in acidic and neutral media was evaluated. Their high cytotoxicity against tumor cells, as well as the drug release upon application of AMF, which leads to an increase in the cytotoxic effect, was demonstrated. © 2022 by the authors. Ministry of Education and Science of the Russian Federation, Minobrnauka: 075-15-2020-777 This research was funded by the Ministry of Science and Higher Education of the Russian Federation, grant number 075-15-2020-777.

Peculiar features of the modification of Fe3O4 magnetic nanoparticles (MNPs) obtained by co-precipitation from solutions of FeII and FeIII salts (10-nm MNPs) and by the gas-condensation method (30-nm MNPs) with 3-aminopropylsilane and then with l-lysine were studied. The chemically obtained MNPs possess more pronounced hydrophilic properties and therefore readily form stable aqueous colloidal solutions and can be loaded with a larger amount of l-Lys. However, samples based on the physically obtained MNPs were characterized by more efficient internalization and longer retention times by the NIH 3T3 cells. The results obtained can be used in the design of novel nanomaterials for magnetic cell labeling.

Surface modification of magnetic nanoparticles (MNPs) with tetramethylorthosilicate and 3-aminopropyltrimethoxysilane was studied. The use of N-phosphonomethyliminodiacetic acid for the stabilization of the initial MNPs can significantly increase the coating thickness and specific surface area of SiO2/APS-modified (APS is 3-aminopropylsilane) MNPs. The possibility of sorption of antitumor drug doxorubicin (DOX) on the synthesized nanoparticles was studied. The degree of sorption of DOX increases with an increase in the specific surface area of the particles.

Magnetic iron nanoparticles (MNPs) encapsulated in a carbon shells and containing sulfo groups on the surface (Fe@C-SO3H) were synthesized. The aggregative stability of aqueous suspensions of the Fe@C-SO3H nanoparticles was studied in solutions of bovine serum albumin and calcium chloride and in phosphate-buffered saline, which simulate blood plasma. It is shown that the Fe@C-SO3H particles practically do not aggregate in the phosphate buffer saline for a long time (several days). On the contrary, MNPs encapsulated in a protein shells using ultrasonic treatment form aggregates up to 110–120 nm in size under these conditions. Suspensions of the Fe@C-SO3H particles are stable in aqueous solutions of calcium chloride in the range of the solid phase concentration between 0.05 and 0.10 g L−1. The results obtained indicate the possibility of using the functionalized Fe@C-SO3H nanoparticles in vitro experiments in biological media.

Derivatives of RGD peptides are promising vector molecules for targeting biomolecules and nanoparticles into tumor tissues and are used for the design of diagnostic agents. The immobilization of the glutaryl-containing derivative of Gly-l-Arg(Pbf)-Gly-l-Asp(OMe)2 (GRGD) tetrapeptide on Fe3O4 magnetic nanoparticles (MNPs) was studied. The results of thermogravimetric and elemental analysis, as well as IR spectroscopy, were used to estimate the amount of organic components at each stage of modification of MNPs.

Molecular dynamics (MD) modeling of the thermal hysteresis of pure metallic gold (Au) is considered in order to study nonequilibrium processes during melting - crystallization phase transformations, i.e. in the transition from solid to liquid. The results of alternative calculations are presented, in which the thermal hysteresis is obtained. The limiting temperatures of overheating of the solid phase during melting and supercooling of the liquid phase during the crystallization of gold have been obtained. The possibility of the formation of highly superheated metastable states of the solid phase upon rapid heating of Au has been confirmed.

The applicability of a high-pressure xenon based spectrometer for determining the parameters of radioactive contamination of soil or building structures by 137Cs resulting from a radiation accident was studied. For soil contaminated by 137Cs with an exponential depth distribution, the Monte Carlo method was used to calculate the characteristics of the radiation field at the detection height and the instrumental gamma spectra. It is shown that there is promise in using such a detector to determine the parameters of the contamination penetration into the interior volume of the material. It is shown that the sensitivity of the measurement of activity along depth depends on the width of the working zone in the valley and the influence of the thickness of the body of the detector is determined.

The article presents the results of the study of the current development direction of applied aspects of the game theory tools application in order to improve the quality of substantiation of selecting managerial decisions by participants in construction activities in relation to the situation of uncertainty in changing the external environment. The authors consider some methodological and applied aspects of modeling the process of substantiating the selection of innovative solutions in the activities of construction organizations using statistical games taking into account the situation of insufficient information for making managerial decisions that affect the efficiency of economic activities of construction participants and generate economic risks. A methodological example of applying game-theoretic modeling is considered in substantiating the selection of priority innovative solutions in the field of industrial-civil and transport construction using the “games with nature” class in a situation of partial uncertainty in changes in the external environment. There have been identified some potential applications of statistical games in combination with probability theory that expand the scope of game-theoretic modeling in order to improve the substantiation quality of selecting priority innovative solutions and reducing economic risks in the activities of construction participants.

Работа посвящена проблемам выявления фундаментальных причин, которые привели к увеличению потребления энергоносителей для нагрева сырья и охлаждения продуктов реакции до требуемых температур, а также к снижению производительности установки гидроочистки дизельного топлива при достижении предельных параметров технологического режима. Цель работы - определение параметров теплообменников, в частности, коэффициентов загрязнения, и параметров технологического процесса, в частности, расход сырья, потребление топливного газа. Мониторинг осуществлялся и при вводе реагентов с целью решения проблем, связанных с образованием смолистых отложений. Выявлено, что реагенты незначительно влияют как на улучшение коэффициента теплообмена, так и на снижение удельного расхода топливного газа. Предложено уточнить дозировку реагентов и разработать проект по использованию реагентов для поддержания чистоты теплообменной поверхности сырьевых теплообменников установки гидроочистки дизельных топлив.

The architecture of a nanoparticles' surface formed due to a modification with a ligand and protein corona formation in biofluids is critical for interactions with cells in vivo. Here we studied interactions of immune cells with magnetic nanoparticles (MNPs) covalently modified with polyethylene glycol (PEG) and their counterparts conjugated with peptides: a pH (low) insertion peptide (pHLIP) and cycloRGD as a targeting ligand in human serum. The conjugation of MNPs-PEG with pHLIP, but not with cycloRGD, enhanced the association of these particles with mononuclear phagocytic cells in vitro and in vivo. We did not find a clear difference in protein corona composition between the pHLIP-modified and parental PEGylated nanoparticles. Analysis of the effect of autologous human serum on MNP uptake by monocytes showed that the efficiency of endocytosis varies among healthy donors and depends on intrinsic properties of serum. Nevertheless, using classic blood, coagulation, biochemical tests, and anti-PEG IgG serum level, we failed to identify the cause of the observed interdonor variation. These individual differences should be taken into consideration during testing of nanotherapeutics.

New derivatives of tetrapeptides GRGD (Gly-Arg(Pbf)-Gly-Asp(OMe)-OMe) and KRGD (Boc-Lys-Arg(Pbf)-Gly-Asp(OMe)-OMe) containing a glutaric acid fragment as a linker were synthesized. The linker provides the possibility for binding these derivatives to other biologically active molecules or nanoparticles.

The possibility of using the transverse relaxation time T2 of protons in aqueous media for quantitative measurement of the capture of magnetic nanoparticles by cells has been studied and demonstrated. The measurement of T2 was performed on a portable original NMR relaxometer with a measuring cell for a standard well of a biological plate. The novelty of the approach is that quantitative measurements of the capture kinetics were carried out using measurements of the proton relaxation time of the nutrient medium, which is determined by the remaining number of magnetic particles (not captured by the cells) in the medium. To study the kinetics of capture, two types of magnetic nanoparticles were synthesized: magnetite particles Fe3O4 and composite particles Fe@C with an iron-carbon shell structure. The surface of the particles was functionalized with amine-and carboxyl groups. The capture of aminated particles of Fe@C cells is established by microscopy and NMR-relaxometry by measuring the time T2. It is shown that the proposed method makes it possible to register very small concentrations of trapped magnetic nanoparticles equal to tens of pg/cell.

The covalent immobilization of a pH-low insertion peptide to aminosilane-coated magnetic nanoparticles with two core diameters (10 and 20 nm) was carried out. The materials obtained were characterized by TEM, XRD, vibrating sample magnetometry, DLS, IR spectroscopy, TGA and elemental analyses. The materials did not have significant cytotoxicity, and they can be used as MRI-guided nanocarriers for tumour targeting.

Magnetic Fe3O4 nanoparticles (MNPs) are often used to design agents enhancing contrast in magnetic resonance imaging (MRI) that can be considered as one of the efficient methods for cancer diagnostics. At present, increasing the specificity of the MRI contrast agent accumulation in tumor tissues remains an open question and attracts the attention of a wide range of researchers. One of the modern methods for enhancing the efficiency of contrast agents is the use of molecules for tumor acidic microenvironment targeting, for example, pH-low insertion peptide (pHLIP). We designed novel organosilicon MNPs covered with poly(ethylene glycol) (PEG) and covalently modified by pHLIP. To study the specific features of the binding of pHLIP-modified MNPs to cells, we also obtained nanoconjugates with Cy5 fluorescent dye embedded in the SiO2 shell. The nanoconjugates obtained were characterized by transmission electron microscopy (TEM), attenuated total reflection (ATR), diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS), dynamic light scattering (DLS), UV and fluorescence spectrometry, thermogravimetric analysis (TGA), CHN elemental analyses, and vibrating sample magnetometry. Low cytotoxicity and high specificity of cellular uptake of pHLIP-modified MNPs at pH 6.4 versus 7.4 (up to 23-fold) were demonstrated in vitro. The dynamics of the nanoconjugate accumulation in the 4T1 breast cancer orthotopically grown in BALB/c mice and MDA-MB231 xenografts was evaluated in MRI experiments. Biodistribution and biocompatibility studies of the obtained nanoconjugate showed no pathological change in organs and in the blood biochemical parameters of mice after MNP administration. A high accumulation rate of pHLIP-modified MNPs in tumor compared with PEGylated MNPs after their intravenous administration was demonstrated. Thus, we propose a promising approach to design an MRI agent with the tumor acidic microenvironment targeting ability.

A procedure for the synthesis of 2-(diethylamino)-N-(2-methylphenyl)acetamide nitrate (monomecaine) exhibiting a pronounced antiarrhythmic activity has been optimized. A procedure for its identification and quality control of the drug substance by HPLC has been developed, and the limit of detection of o-toluidine impurity therein has been estimated at 0.02%. Procedures for HLPC and extraction-titration quantification of monomekain in the drug substance have been proposed and validated. The obtained relative standard deviation (RSD) indicates good specificity, linearity, and precision of the developed procedures.

The immobilization of fluorescent protein TagGFP2 on Fe3O4-based magnetic nano particles (MNPs), preliminarily functionalized with 3-aminopropylsilane and N-(phosphonomethyl) iminodiacetic acid (PMIDA), was studied. Protein binding to MNPs depending on the nature of the surface functional groups, the medium, and the presence of a coupling agent, namely, 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide (EDC), was studied using fluorimetry, UV and IR spectroscopy. It was shown that protein immobilization can occur by both non-covalent and covalent binding with surface groups of MNPs. The best results (up to 150 μg of TagGFP2 per 1 mg of MNPs) were obtained for MNPs preliminarily functionalized with PMIDA and using EDC. The results of this study can be used for the design of imaging agents having both magnetic and optical properties to be applied in biomedicine.

The method of Fe3O4 magnetic nanoparticle synthesis by co-precipitation, modification by 3-aminopropylsilane and conjugation with pH-(low)-insertion peptide (pHLIP) is reported. The characterization of nanoparticles by scanning electron microscopy, transmission electron microscopy, Fourier-transform infrared spectroscopy, elemental and thermogravimetric analyses as well as dynamic light scattering and z-potential measurements is provided. The effect of nanoparticles on the viability of mouse and human peripheral blood mononuclear cells is tested by flow cytometry. The experimental details of nanoparticle administration to tumor-bearing mice, magnetic resonance imaging scanning as well as subsequent tumor sample collection and their processing for transmission electron microscopy, inductively coupled plasma atomic emission spectroscopy, histological and immunohistochemical analyses are described. Biodistribution of the nanoparticles in mice and blood serum analysis data for experimental animals are given. The data are useful for an experiment workflow design and for the development of theranostic systems based on magnetic nanoparticles. © 2020 The Authors Russian Foundation for Basic Research, RFBR: 18-015-00319_a Ministry of Education and Science of the Russian Federation, Minobrnauka: RFMEFI62117X0015 This work was supported by the Russian Foundation for Basic Research [grant number 18-015-00319_a ]. The ICP-AES measurements were carried out using the core facilities of TPU's “Physical and chemical methods of analysis” (project VIU-RSCBS-142/2019). The research involving PBMC experiments was carried out within the framework of the state assignment theme (No. AAAA-A18-118031490008-7) of the Siberian State Medical University. The research into nanoparticle characterization by IR spectroscopy, elemental analysis (CHN) and TGA was carried out within the framework of the state assignment theme (No. АААА-А19-119011790130-3) in the Joint-Use Center for Spectroscopy and Analysis of Organic Compounds, Postovsky Institute of Organic Synthesis UB RAS. Dynamic light scattering (DLS) and zeta potential (z P ) characterization were carried out within the framework of the state assignment theme No. АААА-А18-118020290129-5 in the Miheev Institute of Metal Physics UB RAS. The experiments with animals and MRI were carried out at the Center for Genetic Resources of Laboratory Animals at the Institute of Cytology and Genetics SB RAS, supported by the Ministry of Education and Science of Russia (Unique identifier of the project RFMEFI62117X0015 ). TEM analysis was carried out at the Multiple-access Center for Microscopy of Biological Subjects, Institute of Cytology and Genetics SB RAS.

Systematic and in-depth studies of the structure, composition, and efficiency of hydrogen evolution reactions (HERs) in MoSx films, obtained by means of on- and off-axis pulsed laser deposition (PLD) from a MoS2 target, have been performed. The use of on-axis PLD (a standard configuration of PLD) in a buffer of Ar gas, with an optimal pressure, has allowed for the formation of porous hybrid films that consist of Mo particles which support a thin MoSx~2+δ (δ of ~0.7) film. The HER performance of MoSx~2+δ/Mo films increases with increased loading and reaches the highest value at a loading of ~240 μg/cm2. For off-axis PLD, the substrate was located along the axis of expansion of the laser plume and the film was formed via the deposition of the atomic component of the plume, which was scattered in Ar molecules. This made it possible to obtain homogeneous MoSx~3+δ (δ~0.8–1.1) films. The HER performances of these films reached saturation at a loading value of ~163 μg/cm2. The MoSx~3+δ films possessed higher catalytic activities in terms of the turnover frequency of their HERs. However, to achieve the current density of 10 mA/cm2, the lowest over voltages were −162 mV and −150 mV for the films obtained by off- and on-axis PLD, respectively. Measurements of electrochemical characteristics indicated that the differences in the achievable HER performances of these films could be caused by their unique morphological properties.

The paper presents the results of research in the technical diagnostics field. The criterion for assessing the state based on the parameters of the vibroacoustic signal characteristic function was selected and substantiated as a result of the conducted research. The proposed criterion is integral evaluation and makes it possible to form diagnostic signs of rolling bearings faults and failures of components for reciprocating compressors. In this work, the boundary values of the diagnostic signs are investigated on the basis of the values for the area under the curve of the modulus for the vibroacoustic signal characteristic function. The decision-making risk curves are built, the probabilities of missing a fault and a false alarm for selected values of diagnostic signs are calculated. The using of the proposed diagnostic signs in the system of the fault the defining criteria for rolling bearings and piston compressors makes it possible to increase diagnosis reliability.

The mechanism of N-phosphonomethyl iminodiacetic acid (PMIDA) binding with the Fe3O4 magnetic nanoparticle (MNPs) surface by Fourier transformed infrared spectroscopy, X-ray photoelectron spectroscopy and thermogravimetry was comprehensive studied. To study of microstructure, size and core structure of synthesized nanoparticles the scanning electron microscopy, X-ray diffraction analysis and Raman spectroscopy were carried out. A new scheme for the tridentate bonding of the phosphonomethyl derivative with surface Fe atoms involving unequal P O Fe bonds was proposed. The mechanism of thermal decomposition of PMIDA molecules on the MNP surface was studied using a thermogravimetric analyzer combined with infrared spectrometer. It was shown for the first time that during the thermal treatment of phosphonomethyl-modified MNPs, PMIDA molecules are not desorbed from the surface of MNPs but gradually decompose. We believe that obtained in this work data will be useful for a deeper understanding of the mechanisms of phosphonic acid derivatives interaction with MNPs, as well as in the design of new biomedical materials, in which the conjugation of biomolecules with carboxyl groups of PMIDA-modified MNPs is assumed.