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Results of studying the catalytic properties of systems based on complexes with [Pd(Cp)(L)n]m[BF4]m (where Cp = η5-C5H5; n = 2, m = 1: L = tris(ortho-methoxyphenyl)phosphine, triphenylphosphine, tris(2-furyl)phosphine (TFP); n = 1, m = 1: L = 1,1'-bis(diphenylphosphino)ferrocene, 1,3-bis(diphenylphosphino)propane, 1,4-bis(diphenylphosphino)butane, 1,5-bis(diphenylphosphino)pentane; n = 1, m = 2 or 3: L = 1,6-bis(diphenylphosphino)hexane) in the addition homo- and copolymerization of norbornene (NB) and NB derivatives have been described. It has been found that these complexes can be activated with Lewis acids (BF3⋅OEt2 or AlCl3). The productivity of the [Pd(Cp)(PPh3)2][BF4]/BF3⋅OEt2 catalyst system in NB polymerization can achieve 188 800 molNB . The homopolymerization of 5-methoxycarbonylnorbornene and the copolymerization of NB with 5-methoxycarbonylnorbornene or 5-phenylnorbornene in the presence of BF3⋅OEt2 and [Pd(Cp)(L)2][BF4] (L = PPh3 or TFP) has been studied. A hypothesis for the formation of the catalyst via the intramolecular rearrangement of the η5-Cp ligand into the η1-Cp form upon interaction with a Lewis acid has been proposed. The structure of the [Pd(Cp)(TFP)2]BF4 complex (I) has been determined by X-ray diffraction (XRD) analysis. In the crystal structure of complex I, the coordination sphere of palladium is characterized by a slight distortion of the square planar geometry of the central atom, while the cyclopentadiyl moiety is in an eclipsed conformation. Based on XRD data, the steric hindrance of the TFP ligand has been determined (cone angle is 149°). [ABSTRACT FROM AUTHOR]

The responses of tumor stem cells and various populations of CD4 and CD8 T cells of young and aged C57BL/6 mice were studied in a lung cancer model. Using Lewis lung carcinoma cell line, an orthotopic model of lung cancer was modeled. Cancer stem cells, circulating tumor cells, and various populations of CD4 and CD8 T cells in the blood and lung tissue were studied by cytometry. We revealed age-related differences in the content of various populations of CD4 and CD8 T cells in the blood and lungs of intact young and aged mice. Age-related features of the reaction of various populations of cancer stem cells and CD4 and CD8 T cells in the blood and lungs of animals in the Lewis lung carcinoma were shown. [ABSTRACT FROM AUTHOR]

Regenerative processes in the liver were studied in 3-month-old (young) and 9-month-old (aged) male Wistar rats on day 1 after 30 and 70% hepatectomy. Regardless of the resected liver volume, shifts in the biochemical parameters of the serum in aged rats were more pronounced than in young animals. After 30% hepatectomy, no age differences in the rate of hepatic regeneration were found, while after 70% liver resection this parameter was higher in young rats. Hepatectomy in young rats led to recruitment of MSC, hepatocyte precursors, endothelial and epithelial progenitor cells into the liver parenchyma and increased fluidity of the plasma and mitochondrial membranes of hepatocytes. In aged rats, the recruitment of MSC, hepatocyte precursors, and endothelial progenitor cells into the injured liver was impaired and the rigidity of the mitochondrial membranes of hepatocytes increased. [ABSTRACT FROM AUTHOR]

A new cationic palladium complex [Pd(η5-C5H5)(PPh2Cy)2]BF4 (I) is prepared by the reaction of [Pd(acac)(PCyPh2)2]BF4 with cyclopentadiene in the presence of BF3·OEt2. The structure of complex I is determined by XRD. Results of the DFT studies at the BP86-D3/def2-TZVP level of theory along with QTAIM and NOCV methods suggest that the hapticity of the cyclopentadienyl ligand in I adopts an intermediate type of coordination between η3 and η5. Compound I demonstrates a catalytic activity in the reaction of 1,3-butadiene telomerization with methanol with a catalyst turnover number up to 43100 (mol·BD)/(mol·Pd) for 6 h and a 76% selectivity to telomeres. [ABSTRACT FROM AUTHOR]

Resolved spectroscopic binaries are unique among other types of binaries. They provide the only possibility (aside from trigonometric parallaxes) to accurately determine distances to objects, which is one of the most important characteristics in astronomy. Such binaries are not numerous, but an exhaustive catalog of them still does not exist. The authors have developed a pilot version of a new catalog of resolved spectroscopic binaries. It contains information about orbital elements, component masses, parallaxes, and other parameters for 107 stars. Thus, the catalog represents the most extensive list of resolved spectroscopic binaries known to date. A preliminary analysis of the distributions of the stellar parameters of the objects in the catalog has been carried out, as well as a comparison of the trigonometric parallaxes from Gaia DR3 with the orbital parallaxes. The article is partly based on a report presented at the conference "Modern Stellar Astronomy-2022," which was held at the Caucasian Mountain Observatory of the Astronomical institute of Lomonosov Moscow State University on November 8–10, 2022. [ABSTRACT FROM AUTHOR]

We studied the effects of the extract of the terrestrial part of Aconitum baicalense in BALB/c female mice at the early stages after the injection of N-methyl-N-nitrosourea (MNU). The extract reduced inflammatory activity and tumor growth in the mammary gland. The antitumor and anti-inflammatory effects of the extract are based on the inhibition of cancer stem cells, hematopoietic stem cells, and hematopoietic progenitor cells that promote inflammation. The extract of A. baicalense disrupted the recruitment of epithelial progenitor cells and angiogenesis precursors to the mammary gland preventing neovascularization and transformation of epithelial cells into tumor cells. [ABSTRACT FROM AUTHOR]

Thiosulfate is a sulfur species in an intermediate oxidation state between sulfate and sulfide. It appears during bacterial and chemical sulfide oxidation processes. Thiosulfate plays a prominent role in sulfide oxidation and its presence may clarify the mechanism of redox reactions in the biogeochemical cycles of sulfur and carbon. This study presents the thiosulfate distribution, determined by the derivatization technique with the reagent 2,2'-Dithiobis(5-nitropyridine), in the upper part of the anoxic water column of Black Sea in 2018–2021. The studies were carried out annually at the station located seaward of Gelendzhik in the area of continental slope. Independently of observation time, the thiosulfate concentration increases with depth simultaneously with increasing sulfide. Thiosulfate concentration above the detection limit of 0.01 µM is found at water depths with a density (σθ) of 16.3 kg/m3 and sulfide concentration of 8–11 µM. Thiosulfate reaches its maxima of 0.30 µM at the maximal studied depth of 600 m. We suggest that in the absence of oxidants in anoxic waters, the appearance of thiosulfate is attributed to the sulfate reduction process in the reductive part of the sulfur cycle. Thiosulfate disappears in the upper part of anoxic water column before sulfide. [ABSTRACT FROM AUTHOR]

The effect of ketanserin on inflammation, liver fibrosis, and microviscosity of the plasma and mitochondrial membranes of hepatocytes was studied on young (3 months) and old (9 months) male Wistar rats with experimental liver cirrhosis. Ketanserin reduced inflammation, area of the connective tissue, and liver damage and improved serum biochemical parameters in rats of both age groups; in old rats, the effects were more pronounced than in young animals. In old rats, ketanserin reduced polarity of hepatocyte plasma and mitochondrial membranes in the area of protein-lipid contacts, which determined higher effectiveness of ketanserin during the treatment of liver cirrhosis in aged animals. [ABSTRACT FROM AUTHOR]

Abstract—Two classical theories of synchronization of main-sequence components in binary systems developed by J.P. Zahn and J.-L. Tassoul are considered. These two theories predict significantly different synchronization time scales. Within the framework of this study, the times and probabilities of synchronization for a set of O–G-type model stars are estimated and compared with the results based on recent observational data from the catalog of detached eclipsing binaries by G. Torres. For each of the catalog objects, the maximum period of axial rotation is computed and compared with the known orbital period. A conclusion about the synchronization of each of the systems is then made based on the above theoretical estimates. Zahn's theory, which yields longer synchronization time scales, is found to describe the observational data better than Tassoul's theory. The results of this analysis will be useful for estimating the probability of synchronization in binary systems. [ABSTRACT FROM AUTHOR]

Various stem cells were studied in female BALB/c mice at the early terms after administration of N-methyl-N-nitrosourea to search early diagnostic markers and therapeutic targets. At these terms, damage to the epithelium and endothelium, inflammation, and fibrosis were observed in the mammary gland, but the tumor was not detected. Cancer stem cells, hematopoietic stem cells (HSC), hematopoietic progenitor cells, angiogenic precursors, and epithelial progenitor cells were found in the blood and mammary gland. Cancer stem cells (CD44+CD24—) are proposed as the early diagnostic marker of breast cancer, and short-living HSC, hematopoietic progenitor cells, and angiogenic precursors (CD45—CD117+FLK-1+) as predictors of the formation of tumor microenvironment. [ABSTRACT FROM AUTHOR]

The structure of complex [Pd(acac){P(NEt2)3}2]BF4 (I) is determined by XRD. In the crystal structure of I, the coordination sphere of palladium is characterized by a significantly distorted planar-square geometry of the central atom. Steric hindrance of the P(NEt2)3 ligand is determined using the XRD and DFT data (the Tolman cone angle is 170-175°). It is established that the pair of P(NEt2)3 ligands in the coordination sphere of palladium is represented by two isomers differing by the geometries (planar and pyramidal) of the nitrogen atom environment. DFT calculations at the BP86/def2-TZVP level of theory suggest that the difference between the substituent geometries in the ligands is due to steric hindrances. In combination with BF3·OEt2, compound I demonstrates catalytic activity in the addition polymerization of norbornene whose average activity reaches 3.6·105 g(NB)/(mol(Pd)·h) at 100 °C. [ABSTRACT FROM AUTHOR]

The viscosity of plasma and mitochondrial membranes of hepatocytes was studied in young (3-month-old) and old (9-month-old) male Wistar rats. It was shown that viscosity of hepatocyte plasma and mitochondrial membranes in young rats under optimal vital functions in the area of protein—lipid membrane contacts was significantly lower than in old rats. No age-related differences in the viscosity of lipid—lipid membrane contacts and in the polarity of protein—lipid contacts and lipid layers were found. Liver cirrhosis induced by carbon tetrachloride and ethanol administration was associated with increased fluidity of the plasma and mitochondrial membranes of hepatocytes in rats of both age groups. The decrease in membrane viscosity in young rats occurred due to a decrease of the viscosity in the area of protein—lipid and lipid—lipid contacts, while in old rats in the area of protein—lipid contacts. Carbon tetrachloride and ethanol did not affect the polarity of lipid contacts and lipid layers. [ABSTRACT FROM AUTHOR]

Reaction of Pd(acac)2 with BF3·OEt2 in the presence of tri(2-furyl)phosphine in toluene yields complex [Pd(acac)(TFP)2]BF4 (I) (TFP is tri(2-furyl)phosphine) whose structure is determined by XRD. The crystal structure of I contains short H⋯F contacts. The energies of these contacts are studied using DFT quantum chemical methods. Coordination complex I in combination with BF3·OEt2 in appropriate concentrations and solvents demonstrates catalytic activity in the reaction of morpholine allylic alkylation characterized by the catalyst turnover number from 198 mol to 268 mol of 4-allylmorpholine per mole of palladium and an integral selectivity to the main product of 88-99%. [ABSTRACT FROM AUTHOR]

We studied the age-related characteristics of the response of stem cells and liver in male Wistar rats to administration of carbon tetrachloride (CCl4) and ethanol. It was shown that modeling of liver cirrhosis caused inflammation, fibrosis, damage to sinusoidal capillaries, necrosis, and disturbances in the functional activity of hepatocytes in young rats. These processes were accompanied by mobilization of profibrotic mesenchymal stem cells (MSC), proinflammatory hematopoietic stem cells (HSC) and lymphocytes (CD45hiCD133+) from the bone marrow into the blood and migration to the liver. On the other hand, the number of hepatocyte precursors expressing Sox9 (cells of Hering's canal), immature cholangiocytes, Ito cells, oval cells, and endothelial cells of the liver sinusoids) sharply increased in the liver. In young rats, mobilization and migration of MSC, HSC, and hepatocyte precursors against the background of liver cirrhosis were more intensive than in old animals. The higher resistance of old rats to exposure is associated with age-related changes in the niches as well as in mobilization and migration of cells. [ABSTRACT FROM AUTHOR]

We studied the formation of injuries in lung endothelium and the response of angiogenesis cells during modeling of pulmonary emphysema in male and female C57BL/6 mice with metabolic disorders. Hemodynamic disturbances and reduction in the area of the microvasculature caused by combined pathology in male mice were more pronounced than in females. Mobilization and migration of angiogenic precursors were impaired in both male and female mice. In males, activity of recruiting endothelial progenitor cells, vascular smooth muscle cells, luminal cells of nascent vessels and pericytes into the lungs was additionally reduced. In females, accumulation of endothelial progenitor cells (CD45—CD31+CD34+), vascular smooth muscle cells, and pericytes in the lungs was observed, which indicated activation of endothelial regeneration. Sex differences in the reaction of the lung endothelium and angiogenesis cells can be explained by genetic factors of lipid and glucose metabolism. [ABSTRACT FROM AUTHOR]

We studied the effects of spiperone, a selective blocker of dopamine D2 receptors, on the model of pulmonary emphysema provoked by administration of elastase and D-galactosamine hydrochloride to female C57BL/6 mice and characterized by activation of proteases in the lungs and systemic deficiency of its inhibitor α1-antitrypsin. In this model, spiperone prevented the development of inflammatory reaction and reduced the area of emphysematous expanded alveolar tissue. The expression of angiogenic marker CD31 in the lungs increased under these conditions. Regeneration of the damaged microvascular bed under the action of spiperone resulted from recruiting of Notch1+ endothelial progenitor cells (CD45—CD31+CD34+) into the lungs and blockade of the inhibitory effect of dopamine on phosphorylation of VEGF-2 receptors in endothelial cells of different maturity. In addition, spiperone produced a protective effect on hepatocytes and restored the production and secretion of α1-antitrypsin by these cells. [ABSTRACT FROM AUTHOR]

The changes in endothelial progenitor cells and progenitor cells of angiogenesis, pericytes and smooth muscle cells, were studied in female C57BL/6 mice with a combination of metabolic impairments induced by injections of sodium glutamate and lung emphysema modeled by the administration of cigarette smoke extract. It was observed that sodium glutamate significantly enhances pathological changes in the lungs (inflammation and lung emphysema) induced by the administration of cigarette smoke extract. Recruiting of endothelial progenitor cells (CD45—CD31+CD34+ and CD31+CD34+CD146—) and progenitor cells of angiogenesis (CD45—CD117+CD309+) was registered in the injured lungs. Angiogenesis impairment induced by combined exposure is related to altered migration of pericytes (CD31—CD34—CD146+) and smooth muscle cells (CD31—CD34+CD146+) in emphysema-like enlarged lung tissue. [ABSTRACT FROM AUTHOR]

We studied the effects of elastase, cigarette smoke extract, D-galactosamine hydrochloride, and tyrosine kinase inhibitor SU5416 on endothelial progenitor cells and angiogenesis precursors, as well as on Notch-1 expression by immature endothelial cells. Simultaneously with pulmonary emphysema, different damaging factors with diverse mechanisms of action caused pathological changes in the microvascular network of the lungs and destroyed the alveolar endothelium in female C57Bl/6 mice. D-galactosamine hydrochloride disturbed mobilization of endothelial progenitor cells expressing VEGFR (CD45—CD309+) and angiogenesis progenitors (CD45—CD309+CD117+) and their migration into emphysema expanded lungs. Elastase inhibited VEGFR-expressing endothelial progenitor cells, while cigarette smoke extract inhibited cells with CD45—CD31+CD34+ phenotype. In pulmonary emphysema provoked by elastase or D-galactosamine hydrochloride, angiogenesis was provided by endothelial cells with CD45—CD31+CD34+ phenotype, whereas in emphysema modeled with SU5416 or cigarette smoke extract, it was provided by the endothelial VEGFR-expressing cells and mature CD31+ endothelial cells, respectively. Replenishment of immature endothelial cells damaged by elastase and SU5416 involved Notch-1+ angiogenesis precursors and Notch-1+ endothelial progenitor cells with VEGFR. [ABSTRACT FROM AUTHOR]

The effects of the pegylated form of glucagon-like peptide 1 (pegGLP-1) on oligopotent β cell precursors (CD45—TER119—CD133+CD49flow) in the pancreas were studied in C57Bl/6 mice. Under conditions of streptozotocin-induced type 1 diabetes mellitus, intraperitoneal injection of pegGLP1 increased the content of β cell precursors and dithizone-stained cells in the pancreas. β Cell precursors of mice with diabetes demonstrated high self-maintenance potential. In contrast to pegGLP-1, native GLP-1 did not affect β cell precursors in diabetic animals. Treatment of a culture of β cell precursors from mice with diabetes induced the yield of dithizone-stained mononuclears. In conditioned mediums of dithizone-positive cells obtained as a result of differentiation of β cell precursors from mice with diabetes, insulin was detected after administration of pegGLP-1 (10—7 M) and glucose (3 mmol/liter); the level of insulin increased with increasing glucose concentration (to 20 mmol/liter). The in vitro effect of pegGLP-1 did not differ from the effect of GLP-1 (10—7 M). [ABSTRACT FROM AUTHOR]

Biogeochemical structures of three permanently stratified waterbodies were studied: a sea water basin (the Black Sea), an estuary (Hunnbunn fjord), and a freshwater lake (Nordbytjernet), with focus on the distributions of methylmercury (MeHg) and total mercury (THg). THg concentrations were similar in the sea water basin (0.2-1.8 ng/L) and the freshwater lake (0.8-1.2 ng/L), but significantly higher in the estuary (0.6-9.4 ng/L). An increase in the MeHg concentration and MeHg/THg ratio were found in the redox zone in all three basins, indicating bacterial production of MeHg in the aqueous phase. In the lake and estuary, the maximum MeHg concentration and MeHg/THg ratio were found in samples located closest to the bottom sediments, likely due to the formation of MeHg in surface sediments and subsequent diffusion to the overlying waters. [ABSTRACT FROM AUTHOR]

The determination of iron(II) with 1,10-phenanthroline in aqueous solutions was carried out exemplarily by thermal lens spectrometry. The peculiarities of analytical reactions at the nanogram level of reactants can be studied using this method. Under the conditions of the competing reaction of ligand protonation, the overall stability constant for iron(II) chelate with 1,10-phenanthroline was determined at a level of n × 10–7 mol L–1, log β 3 = 21.3 ± 0.1. The rates of formation and dissociation of iron(II) tris-(1,10-phenanthrolinate) at a level of n × 10–8 mol L–1 were found to be (2.05 ± 0.05) × 10–2 min–1 and (3.0 ± 0.1) × 10–3 min–1, respectively. The conditions for the determination of iron(II) with 1,10-phenanthroline by thermal lensing were reconsidered, and ascorbic acid was shown to be the best reducing agent, which provided minimum and reproducible sample pretreatment. Changes in the conditions at the nanogram level improved both the selectivity and sensitivity of determination. The optimum measurement conditions for thermal lensing were determined not only by the absorption of the analyte and reagents, but also by the background absorption of the solvent. The limits of detection and quantification of iron(II) at 488.0 nm (excitation beam power 140 mW) are 1 × 10–9 and 6 × 10–9 mol L–1, respectively; the reproducibility RSD for the range n × 10–8–n × 10–6 mol L–1 is 2–5%. [ABSTRACT FROM AUTHOR]

The dependence of the representative weight of a geological sample of quartz sulfide gold-containing ores on their particle size is studied. It is shown that the weight of the furrow samples selected in the chemical assay of gold-containing ores of the first group can be reduced two-to threefold. [ABSTRACT FROM AUTHOR]

The assembly of ball screws is considered theoretically and experimentally in the case where the screw and nut are combined with an optimal combination of systematic and random errors in the screw pitch (optimal pitch error ratio). [ABSTRACT FROM AUTHOR]

The title of the article should read: "Role of β Cell Precursors in the Regeneration of Insulin-Producing Pancreatic β Cells under the Influence of the Pegylated Form of Glucagon-Like Peptide 1". [ABSTRACT FROM AUTHOR]