The degeneration of cartilage in articular joints is a significant medical concern due to its high incidence rate. Damaged articular cartilage has a limited ability to regenerate naturally and thus often requires regenerative therapy. Intra-articular matrix-associated autologous chondrocyte transplantation, which involves the introduction of chondrocytes into the damaged area either as part of tissue-engineered constructs with a carrier matrix (scaffold) or in the form of tissue spheroids (chondrospheres), is generally considered the gold standard for treating such defects. This approach is probably the most biomimetic restorative articular cartilage treatment in the sense that it supports the cells in spheroids to produce and accumulate their own extracellular matrix. The growing interest in large-scale production of such biomedical cellular products raises the question of accessible and effective methods for assessing the quality of obtained chondrospheres, both in terms of their chemical composition and biological properties. Here, a sensor prototype based on comparative electrochemical profiling of chondrospheres is proposed for quantitative assessment of the accumulation of extracellular matrix components in hyaline cartilage.

Plant microbial fuel cells (PMFC) offer a promising alternative to traditional electricity sources. However, their practical application is limited due to poor electrochemical performance, which is enhanced using various electrode modifications. In this study, MnO₂ was electrochemically deposited on the surface of carbon felt and then used as a bifunctional material for the anode and cathode configurations in PMFC systems. The modified carbon felt samples were characterized in terms of electrochemically active surface area and the number of defects determined using cyclic voltammetry and Raman spectroscopy. The resulting density power was 15, 2, and 33 mW/m² for the control system, PMFC-anode-MnO₂, and PMFC-cathodeMnO₂, respectively. Thus, the deposition of MnO₂ on the cathode in PMFC systems results in a twofold increase of electrical energy generation.

The complexation of new complexones, analogues of nitrilotriacetic (H₃NTA) and nitrilotrimethylenephosphonic (H₆NTP) acids containing monobasic (O-alkyl)methylenephosphonic fragments as donor groups, with trivalent cations of lanthanides was studied. The stability and deprotonation constants of 1:1 complexes and the fractional distribution of complex forms were determined using pH-metric titration in combination with mathematical modeling. The complexation properties of N-[(O-butyl)hydroxyphosphorylmethyl]iminodiacetic acid were compared with those of H₃NTA based on the linear free-energy relationships.

The antioxidant capacity and phenolic composition of Cistanche tinctoria (Orobanchaceae) were evaluated in the crude, flavonoid, and tannin extracts prepared from air-dried flowers using methanol, ethyl acetate, and acetone, respectively. The highest extraction yield (11.3 %) was obtained with the crude extract. The elevated total phenolic (168 ± 24 mg GAE/g) and flavonoid (27 ± 3 mg QE/g) contents in the crude extract were revealed. The tannin extract exhibited the highest antioxidant activity (IC₅₀ 8 ± 2 µg/mL), but, in terms of antioxidant and antiradical properties, all extracts were significantly less effective than ascorbic acid. The flavonoid extract demonstrated the greatest hemolysis inhibition (23 %). The highest absorbance (0.432) was observed for the tannin extract at a concentration of 0.1 mg/mL. Based on the high-performance liquid chromatography analysis, chlorogenic acid and naringenin were identified as the major phenolic compounds in the crude extract. The results validate the health benefits of phenolic compounds in C. tinctoria and highlight further research priorities for its applied and medicinal use.

Isonicotinoyl hydrazone of 6-carbaldehyde pyridoxine 1, existing as a mixture of E and Z isomers, is known to exhibit potent activity against drug-resistant strains of M. tuberculosis. This article continues earlier research on the development of anti-tuberculosis drugs by examining the photostability of compound 1 and its structural analogs, which is important for the production of pharmaceutical substances and the determination of the specific activity of various isomers in vivo. Under the action of UV irradiation, a significant tarring of the reaction mixture in the solutions of compounds 1 and 2 containing free hydroxymethyl groups at positions 4 and 5 of pyridoxine was observed, apparently due to the formation of reactive ortho-quinone methides. However, when ketal protection was employed for hydroxymethyl groups in the pyridoxine derivative containing the isonicotinoyl hydrazone fragment at position 6, a transition from the thermodynamically more stable E isomer to Z isomer was induced by UV irradiation through the formation of an intramolecular hydrogen bond of the NH...N_pyr type. In contrast, owing to the presence of an intramolecular hydrogen bond of the OH...N_C=N type, the pyridoxine derivative bearing the isonicotinoyl hydrazone fragment at position 2, underwent no significant photoisomerization.

Obtaining spatial structures with high resolution by the XRD method is still associated with significant difficulties for laboratory single-crystal diffractometers incorporating modern confocal multilayer optics with high intensity and small X-ray beam diameter (≤ 100 μm). As the unit cell size increases, the distance between reflections in the diffraction pattern decreases, which leads to their overlapping. To minimize the overlap and separate reflections as distinct peaks, the distance from the crystal to the detector is traditionally increased. However, this approach is not always successful due to the divergence of the X-ray beam. A potential alternative solution is to optimize the beam divergence parameters in the optical device of the X-ray source. Using an Era protein crystal from Staphylococcus aureus with large unit cell parameters (a = b = 78.1(1) Å and c = 244.9(2) Å), a successful optimization of the X-ray beam divergence parameter selection for high-resolution XRD data acquisition was demonstrated.

This study evaluates the antifibrotic properties of Xymedon, a pyrimidine derivative (1,2-dihydro-4,6-dimethyl-1-(2-hydroxyethyl)-pyrimidin-2-one), and its conjugate with L-ascorbic acid in a rat model of experimental liver fibrosis. Liver fibrosis was induced in female Wistar rats by oral administration of 5 % oil solution of CCl₄ at a dose of 2 mL/kg twice weekly and 5 % ethanol in drinking water with constant access for 8 weeks. After discontinuing the administration of toxicants, the rats were treated with Xymedon at a dose of 0.24 mg/kg and its conjugate with L-ascorbic acid at an equimolar dose of 0.5 mg/kg for 2 or 4 weeks. Histological evaluation of the liver tissue was performed using hematoxylin– eosin and Van Gieson’s staining. Serum biochemical indicators of liver function were determined. Additionally, the cytokine profile of the liver tissue and serum was examined using the MagPix multiplex immunoassay, and liver COX-2 levels were measured by western blot analysis. The findings demonstrate that the treatment with the conjugate of Xymedon with L-ascorbic acid for 2 weeks significantly promoted fibrosis resolution by reducing the area of collagen fibers in the liver tissue of rats. This treatment also resulted in a more pronounced normalization of blood biochemical parameters, cytokine profile markers, and COX-2 levels compared to Xymedon alone and the untreated control group.

Cell-free translation systems are gaining increasingly widespread use, from both practical and fundamental standpoints. Their applications are diverse but typically revolve around preparative biosynthesis of proteins in cases where expression in living cells is either problematic or unfeasible. They also enable rapid evaluation of the effects produced by external components on the translation process. Existing cell-free systems have been derived from bacterial, yeast, plant, insect, mammalian, and human cells. However, no cell-free systems have been developed from avian cells, despite the ecological and economic significance of birds (in daily life, food production, light industry, agriculture, etc.). Such systems would be powerful biotechnological tools and bring considerable benefits for both poultry farming and fundamental research on the protein synthesis in birds. To address this gap, a cell-free translation system using the extracts from the cells of domestic chicken (Gallus gallus) embryos was developed. Following the sample preparation and mRNA selection, the cell-free biosynthesis of firefly luciferase was performed in a chemically supplemented cell extract.

This article reviews modern methods for harvesting microalgae biomass from culture media, explores their advantages and limitations, as well as argues that the choice of an optimal and efficient method depends on the scale of production, the types of microalgae, and the composition of culture media. Here, the methods of centrifugation, gravity sedimentation, and separation were evaluated for their efficiency in the recovery of Porphyridium purpureum cells. During the experiments, separation outperformed the other two methods in terms of the resulting biomass dry weight and the time consumed. When applied to Porphyridium purpureum, it yielded 20.75 g of dry biomass by processing a 100 times larger volume of the suspension at 1 kW of energy input, thus demonstrating a fivefold increase in overall efficiency compared to centrifugation. To achieve a high biomass concentration ratio and reduce energy costs in the recovery of P. purpureum, a multi-stage harvesting process, combining initial gravity sedimentation with either centrifugation or separation, was proposed. The findings can serve as the basis for developing practical guidelines on selecting an optimal strategy for large-scale harvesting of microalgae.

The demographic, vitality, and spatial structures of Quercus robur L. cenopopulations were examined under different phytocenotic conditions of the Kulikovo Field Museum-Reserve and its surroundings (Tula region), including various oak-dominated stands, small-leaved forests, shrub thickets along forest edges, and meadow steppe areas. A total of 17 cenopopulations were analyzed. These populations occupied the interfluves, as well as the ravine slopes of varying steepness, exposure, and moisture levels in the thalweg. The highest cenopopulation densities were observed in a slope oak stand, small-leaved forests, and meadow steppe areas. All cenopopulations were ontogenetically incomplete, classified as either normal or invasive. Most cenopopulations of the oak stands had ontogenetic spectra peaking at middle-aged generative individuals, with pregenerative stages notably absent. In contrast, most cenopopulations of the small-leaved forests, shrub thickets, and meadow steppe areas exhibited spectral peaks at pregenerative individuals. Individuals with normal vitality were most prevalent in the meadow steppe areas and shrub thickets. The spatial distribution structure was largely uneven. The most favorable conditions for maintaining the flow of generations in the species cenopopulations were revealed in the sparse oak stand on a gentle slope of the moist ravine, as well as in the shrub thickets and meadow steppe areas.

Once ordinary chondrites fall on Earth, Fe–Ni minerals and troilite they contain oxidize and transform into iron oxyhydroxides and/or iron oxides, which is expected to modify their magnetic properties. In this study, the effect of long-term terrestrial weathering on the magnetic properties (magnetic susceptibility and hysteresis parameters) of 117 H and L ordinary chondrites from the Atacama Desert (Chile), a region hosting the oldest meteorite collection in the world, was investigated. The measurements revealed a consistent weathering-induced decrease in the saturation magnetization and magnetic susceptibility of both H and L chondrites. The observed trends indicate a faster initial weathering of Fe–Ni minerals compared to troilite, their transformation into mostly paramagnetic iron oxyhydroxides, as well as the formation of magnetite in the later weathering stages.