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•Synthesis of magnetic fluid-loaded liposomes (MFLs) is developed.•Magnetite concentrations in MFLs for contrasting at T2, T1 images are determined.•MFLs distribution in carcinoma ...upon intratumoral dosing and their MRI are shown.•Lack of toxic MFL effect on normal tissues upon intratumoral dosing is demonstrated.•MFLs are promising agents to effectively increase the contrast in T2 weighted images.
Magnetic fluid-loaded liposomes (MFLs) were fabricated using magnetite nanoparticles (MNPs) and natural phospholipids via the thin film hydration method followed by extrusion. The size distribution and composition of MFLs were studied using dynamic light scattering and spectrophotometry. The effective ranges of magnetite concentration in MNPs hydrosol and MFLs for contrasting at both T2 and T1 relaxation were determined. On T2 weighted images, the MFLs effectively increased the contrast if compared with MNPs hydrosol, while on T1 weighted images, MNPs hydrosol contrasting was more efficient than that of MFLs. In vivo magnetic resonance imaging (MRI) contrasting properties of MFLs and their effects on tumor and normal tissues morphology, were investigated in rats with transplanted renal cell carcinoma upon intratumoral administration of MFLs. No significant morphological changes in rat internal organs upon intratumoral injection of MFLs were detected, suggesting that the liposomes are relatively safe and can be used as the potential contrasting agents for MRI.
Cr–O–N coatings were formed by cathodic arc evaporation at different O2/(N2+O2) relative oxygen concentrations onto HS6-5-2 (DIN standard) steel substrates. The chemical and phase composition, ...surface morphology on the as-deposited coatings were investigated by Wavelength Dispersive Spectrometry, X-ray Diffraction, Atomic Force Microscopy, Scanning Electron Microscopy and Raman Spectroscopy. The coatings deposited in pure nitrogen atmosphere had a cubic CrN structure. Structural properties of the coatings synthesized in mixed oxygen and nitrogen atmosphere depended strongly on the relative oxygen concentration. High relative oxygen concentration caused amorphization of the coating. XRD diffraction lines were shifted and broadened, indicating increasing stress and decreasing mean crystallite size, from 109nm for coatings deposited at relative oxygen concentration equal 0% to 23nm at 20%. The coatings formed at 50% relative oxygen concentration had a rhombohedral Cr2O3 structure with a grain size of about 11nm and lattice distortion of about 2%. Increasing the relative oxygen concentration also increased the surface roughness and the fraction of the surface rate covered by macroparticles.
•Cr-O-N coatings were deposited using cathodic arc evaporation•The increase in the relative oxygen concentration causes macropoarticle number increase•The coatings with oxygen concentrations to 23 at.% have cubic CrN structure and coating with 56 at.% - rhombohedral Cr2O3 structure•The coatings with oxygen concentrations to 23 at.% have lower roughness than coating with 56 at.%•The increase in the relative oxygen concentration causes grain size decrease
The Cr1−xVxN monolayer coatings were synthesized using vacuum arc plasma flux method. The properties of the coatings were compared with CrN and VN, i.e. for coatings where x = 0 or 1. The surface ...morphology, microstructure and chemical composition of (Cr,V)N coatings were investigated using Scanning Electron Microscopy (SEM) and Atomic Force Microscopy (AFM), X-ray Diffraction (XRD) and Energy Dispersive X-ray Spectroscopy (EDS). The mechanical and tribological properties of coatings were characterized using nano-indentation, scratch test and Daimler-Benz test and ball-on-disk tribometer. It was found that the cubic CrN phase was formed. In coatings with vanadium the solid solution (Cr,V)N phase was observed. The diffraction lines of the coatings were shifted to lower angles which indicated the stress occurring there. The roughness parameter Ra increased linearly with vanadium concentration, from about 0.05 µm (CrN) to about 0.13 µm (VN) which was probably connected with significantly higher number of surface defects. The hardness and elastic modulus of Cr1−xVxN coatings increased from 20 GPa (CrN) to 35 GPa (VN) and 300 GPa (CrN) to about 500 GPa (VN) respectively. Adhesion of the coatings was very high. The critical load of the complete coating detachment exceeds 100 N. The highest wear rate was for CrN coating - (1.7 ± 0.1) × 10−6 mm3/Nm, while the lowest was for VN coating - (1.2 ± 0.6) × 10−7 mm3/Nm. The wear mechanism for all coatings against Al2O3 ball was mainly abrasive. The VN coating showed the lowest friction coefficient in the set of coatings investigated.
•Cr-V-N coatings were deposited using cathodic arc evaporation.•Roughness of Cr-V-N coatings increases with vanadium concentration.•Hardness of Cr-V-N coatings increases with vanadium concentration.•Coefficient of friction of Cr-V-N coatings decreases with vanadium concentration.•The wear rate of Cr-V-N coatings decreases with vanadium concentration.
Dysfunction of the oxidative phosphorylation (OXPHOS) system is a major cause of human disease and the cellular consequences are highly complex. Here, we present comparative analyses of mitochondrial ...proteomes, cellular transcriptomes and targeted metabolomics of five knockout mouse strains deficient in essential factors required for mitochondrial DNA gene expression, leading to OXPHOS dysfunction. Moreover, we describe sequential protein changes during post-natal development and progressive OXPHOS dysfunction in time course analyses in control mice and a middle lifespan knockout, respectively. Very unexpectedly, we identify a new response pathway to OXPHOS dysfunction in which the intra-mitochondrial synthesis of coenzyme Q (ubiquinone, Q) and Q levels are profoundly decreased, pointing towards novel possibilities for therapy. Our extensive omics analyses provide a high-quality resource of altered gene expression patterns under severe OXPHOS deficiency comparing several mouse models, that will deepen our understanding, open avenues for research and provide an important reference for diagnosis and treatment.
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Over four years in the spring–summer period, the species composition and the community structure of planktonic heterotrophic nanoflagellates (HNF) were studied in different types of littoral waters ...of the Rybinsk Reservoir (Upper Volga), including those affected by the vital activity of colonial birds. A total of 105 species and forms of HNF from 13 large taxa and a group of uncertain taxonomic position were identified. The taxa Choanoflagellida and Chrysomonadida were represented by the largest number of species in all the littoral zones studied. Fewer species of HNF were recorded in the littoral zone affected by the bird colonies than in areas outside the zones of their influence. The maximum number of species (81) was recorded in the protected overgrown littoral zone, and the minimum (48 species), in the open littoral zone near the heron colony. In the entire littoral area, 35 species were common. Among them, three species (
Bodo designis, Paraphysomonas imperforata,
and
Spumella
sp. 1) had a high frequency of occurrence (≥50%). However, the basis of the diversity of the GNF was formed by the species, the frequency of occurrence of which was less than 20%. However, the species the frequency of which was ≤20% were the basis for the diversity of HNF. They made up more than half of the species list in all habitats. The dominant complex of the littoral communities in the reservoir was represented by 19 species.
The particularities of the impact of the addition of lanthanum cations on the thermochemical behavior of modified zirconium hydroxide were investigated. It is shown that the composition and ...properties of the obtained materials are determined by the concentration of the modifier and the formation temperature of the oxide phase.
A series of the cadmium and zinc carboxylate complexes with anions of pentafluorobenzoic (HРfbz) and 2,3,4,5-tetrafluorobenzoic (HТfbz) acids and N
-
donor ligands (1,10-phenanthroline (Phen) and ...quinoline (Quin)), Cd(Pfbz)
2
(Phen)
n
(
I
), Cd(Рfbz)
2
(Рhen)
2
·2MeCN (
II
), Zn(H
2
O)-(Рfbz)
2
(Рhen) (
III
), Zn
2
Cd(Рfbz)
6
(Рhen)
2
⋅2C
6
H
6
(
IV
), Cd
2
(H
2
O)
2
(Tfbz)
4
(Рhen)
2
(
V
), Cd
2
-(H
2
O)
2
(Tfbz)
4
(Quin)
2
(
VI
), and Cd(Tfbz)
2
(Phen)
2
⋅HTfbz (
VII
), is synthesized. The structures of new complexes
I
–
VII
are determined by X-ray diffraction analysis (CIF files CCDC nos. 1871300, 2005461, 2005462, 2005464, 2005466, 2005465, and 2005459, respectively). The majority of the synthesized compounds is typical of intramolecular stacking interactions between the coordinated molecules of the aromatic N
-
donor ligands and fluorinated substituents of the carboxylate anions. These interactions lead to the formation of unusual compounds, which are different in the cases of pentafluorobenzoates and tetrafluorobenzoates, in particular, coordination polymer
I
and binuclear complexes
V
and
VI
with coordinated water molecules. The synthesized zinc and cadmium compounds differ in structure and composition.
The aim of the present work was investigation of the fluorescent dye thioflavin T (ThT) binding to acetylcholinesterase (AChE). ThT is an effective test for protease activity, as well as a probe for ...amyloid fibril formation. Despite the extended and active investigation of ThT–AChE binding, there is still no common view on the stoichiometry of this interaction. In particular, there is a hypothesis explaining the spectral properties of bound to AChE dye and high quantum yield of its fluorescence by formation of dimers or excimers of ThT. In order to confirm or deny this hypothesis, we proposed a new experimental approach for examination of ThT–AChE interaction based on spectroscopic investigation of samples prepared by equilibrium microdialysis. This approach allowed us to prove 1/1 ThT/AChE binding stoichiometry. The increase of ThT fluorescence quantum yield and lifetime accompanying its binding to AChE can be explained by the molecular rotor nature of this dye. Together with the coincidence of the positions of free and AChE-bound ThT fluorescence spectra, the obtained results prove the groundlessness of the hypotheses about ThT aggregation while binding to AChE. The model of ThT localization in the active site of AChE was proposed by using molecular docking simulations. These results also allowed us to suggest the key role of aromatic residues in ThT–AChE interaction, as observed for some amyloid fibrils.
The dynamics of the size-morphological groups of heterotrophic prokaryotoplankton of the largest freshwater reservoir in the Caucasus, Lake Sevan (Armenia), has been studied, which makes it possible ...to explain its spatiotemporal organization and succession. The lake is characterized by an alternation of stable and unstable periods of existence of hydrobionts due to abrupt changes in environmental conditions, mainly caused by anthropogenic impacts. In the community of planktonic prokaryotes of the lake, the following size-morphological groups were distinguished: small cocci and coccobacilli, small rods and vibrios, medium-sized cocci and coccobacilli, large rods and vibrios, filaments, and particle attached cells. The main contribution (on average 55.5%) to the formation of the prokaryotoplankton biomass of the lake was made by small rods and vibrios. The biomass of each of the groups fluctuated in time and space within relatively narrow limits, and the development of the groups occurred in close relationship to each other. Apparently, different size-morphological groups of prokaryotes are adapted to exist within similar ecological and phylogenetic niches and jointly and consistently perform common functions in the mineralization of organic matter and trophic interactions in the lake. At the same time, these groups implement various ecological strategies that can be successful at different periods of the ecosystem’s existence.
Objective: philosophical reflection problems of the frontiers of science, knowledge and creativity in the modern intercultural integration; rationale for new interpretations and understanding of the ...concept "border" providing an integrative model for science and culture, which, in turn, implies the unacceptability of Orthodox approaches, and rigid demarcation between different spheres of cultural production. This explains the need to develop a "rational-reflexive culture" that meets the new demands of modern society.
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