This article describes the one-pot microwave synthesis of silver nanoparticles (AgNPs) assisted with natural polyelectrolytes—humic substances (HS). The humic polyelectrolytes served both as chemical reductants for silver ions and as end-capping agents for AgNPs. Three commercially available sodium humates extracted from lignites and leonardite and one sodium fulvate isolated from natural brown water seeped through peat deposits were used in this study. The dynamics of the growth rate of AgNPs was characterised by UV–VIS spectroscopy by measuring the intensity of surface plasmon resonance at 420 nm. Transmission electron microscopy was used to characterise the size and morphology of AgNPs. Dynamic light scattering was used to determine size distributions of the synthesised AgNPs in the solutions. It was established that both conventional and microwave syntheses assisted with the coal humates produced small-size AgNPs in the range from 4 to 14 nm, with the maximum share of particles with sizes of (6 ± 2) nm by TEM estimates. The peat fulvate yielded much larger NPs with sizes from 10 to 50 nm by TEM estimates. DLS measurements revealed multimodal distributions of AgNPs stabilised with HS, which included both single NPs with the sizes from 5 to 15 nm, as well as their dominating aggregates with sizes from 20 to 200 nm and a smaller portion of extra-large aggregates up to 1000 nm. The given aggregates were loosely bound by humic polyelectrolyte, which prevented the coalescence of AgNPs into larger particles, as can be seen in the TEM images. The significant acceleration in the reaction time—a factor of 60 to 70—was achieved with the use of MW irradiation: from 240 min down to 210–240 s. The coal humate stabilised AgNPs showed antimicrobial properties in relation to S. aureus. A conclusion was made regarding the substantial advantages of microwave synthesis in the context of time and scaling up for the large-scale production of AgNP-HS preparations with antimicrobial properties suitable for external wound-healing applications.

The umbilical cord is a material that enhances regeneration and is devoid of age-related changes in the extracellular matrix (ECM). The aim of this work was to develop a biodegradable scaffold from a decellularized human umbilical cord (UC-scaffold) to heal full-thickness wounds. Decellularization was performed with 0.05% sodium dodecyl sulfate solution. The UC-scaffold was studied using morphological analysis methods. The composition of the UC-scaffold was studied using immunoblotting and Fourier transform infrared spectroscopy. The adhesion and proliferation of mesenchymal stromal cells were investigated using the LIVE/DEAD assay. The local reaction was determined by subcutaneous implantation in mice (n = 60). A model of a full-thickness skin wound in mice (n = 64) was used to assess the biological activity of the UC-scaffold. The proposed decellularization method showed its effectiveness in the umbilical cord, as it removed cells and retained a porous structure, type I and type IV collagen, TGF-β3, VEGF, and fibronectin in the ECM. The biodegradation of the UC-scaffold in the presence of collagenase, its stability during incubation in hyaluronidase solution, and its ability to swell by 1617 ± 120% were demonstrated. Subcutaneous scaffold implantation in mice showed gradual resorption of the product in vivo without the formation of a dense connective tissue capsule. Epithelialization of the wound occurred completely in contrast to the controls. All of these data suggest a potential for the use of the UC-scaffold.

The bacteriostatic effects of human umbilical cord-derived matrices and hydrogels were examined. The use of biomimetics based on the extracellular matrix of extraembryonic organs, including the human umbilical cord, is promising for regenerative medicine and tissue engineering. Cell-free products from the extracellular matrix of various human organs and tissues are resistant to intentional bacterial contamination. Two acellular scaffolds prepared using different human umbilical cord decellularization protocols and two derived hydrogels were evaluated for their bacteriostatic properties. Two clinical cases of the use of lyophilisates of umbilical cord-derived hydrogels were described. The compositions of human umbilical cord-derived acellular matrices and hydrogels were studied using biochemical analysis techniques. The sensitivities of Staphylococcus aureus and Escherichia coli to umbilical cord-derived matrices and hydrogels were assessed using culture techniques, and metabolic activities of bacteria were also examined. Human umbilical cord-derived acellular matrices and hydrogels consist of collagens and contain proteins and glycosaminoglycans. A significant bacteriostatic effect of hydrogels against Escherichia coli was detected during the first 16 h of incubation, regardless of the type of detergents used for their preparation. The matrices did not show a bacteriostatic effect, which indicates that the hydrolysis of structural components contributes to the release of substances with bacteriostatic activities. The effect was presumed to be due to the influence on the level of metabolic activity of microorganisms. The use of powdered lyophilized hydrogels derived from human umbilical cord as an adjunct to autodermal graft in the treatment of infected deep wounds in two volunteer patients promoted healing without infections. In general, the use of hydrogel lyophilisates from acellular human umbilical cord as an additional treatment allows for the engraftment of skin autografts and promotes the healing of extensive deep wounds at risk of infection.

Background. Hordeum bulbosum L. is the only wild species of the genus Hordeum, the gene pool of which is successfully used in introgressive hybridization to increase the genetic diversity of H. vulgare L. When creating introgression forms based on hybrids of H. vulgare with H. bulbosum, it is necessary to take into consideration the ploidy of the parent species, and their genetic features that determine the intensity of the process of H. bulbosum chromosomes elimination in embryogenesis. The purpose of our investigation was to study the features associated with the elimination of bulbous barley chromosomes in embryos obtained in various combinations of crosses involving the tetraploid hybrid H. bulbosum with H. vulgare for its effective use in obtaining introgression lines of H. vulgare. Material and methods. The analysis was performed on 9-15 days old embryos obtained in crosses of the tetraploid hybrid F2 (H. bulbosum A17 (4x) × H. vulgare ‘Borwina’ (4x)) (HbHbHvHv) with ‘Igri’ (2x) and ‘Borwina’ (2x) barley varieties, with H. bulbosum A17 (4x), as well as during its self-pollination. The chromosomal composition of embryos of different ages was analyzed on squashed embryo slides using genomic in situ hybridization (GISH). Results. Among the 11-15 days old embryos obtained from self-pollination of the hybrid, approximately half of the studied ones were mixoploids, while in other embryos the majority of cells contained only the genomic material of H. vulgare. The elimination process was very intensive in crosses of the hybrid with the barley varieties ‘Igri’ (2x) and ‘Borwina’ (2x), and by day 10-11 after pollination cells containing only the genomic material of H. vulgare predominated in all embryos, regardless of the direction of crossing and the variety used. Hybrid embryos with a stable chromosomal composition resulted from a cross of a tetraploid hybrid with H. bulbosum A17 (4x). Embryos with recombinant H. vulgare chromosomes carrying alien genetic material of bulbous barley were identified in all types of crosses. Conclusion. The most efficient way for the mass production of introgression lines of cultivated barley varieties based on the partially fertile hybrid F2 (H. bulbosum A17 (4x) × H. vulgare ‘Borwina’ (4x)), is the crossing with varieties of H. vulgare (2x). The progeny from such crosses will contain only cultivated barley plants, among which it is possible to identify forms with the introgression of H. bulbosum and use already the first generation from their self-pollination for selecting H. vulgare lines carrying the genetic material of bulbous barley in both homologs.

BACKGROUND: Whartons jelly of the human umbilical cord is one of the sources of multipotent mesenchymal stromal cells. The cell population obtained from the postpartum biomaterial is characterized by high proliferative and regenerative properties. Isolation of a culture of multipotent mesenchymal stromal cells from the umbilical cord does not pose a threat to the health and life of the donor. AIM: Optimization of the technique for isolating a reproducible population of multipotent mesenchymal stromal cells from Whartons jelly is an urgent task in biomedicine, which can accelerate the process of obtaining donor cells for cell therapy and tissue engineering. MATERIALS AND METHODS: In the study, the main techniques and methods for isolating the culture of umbilical cord stroma cells were tested, the cultivation process was optimized to increase its efficiency and reduce the time of growth of cell biomass. The effect of the components of the nutrient medium on the cells obtained from Whartons jelly of the human umbilical cord was studied. Currently, there is no universal composition of the growth medium; in various studies, nutrient media from different manufacturers are used, which differ in composition. The most discussed issue is the selection of serum, which is part of the nutrient medium. RESULTS: In the work, a comparative evaluation of five different sera was carried out. It has been shown that the most stable physiological parameters are observed in cell suspension samples with the addition of FBS (SKPK, Russia) and FBS (Capricorn, USA) sera. A study of the effect of hypoxia on cell culture in combination with the most effective sera showed that hypoxic stress acts as an activator of primary cell proliferation. The assessment of the effect of serum and hypoxia on cell culture was carried out visually using microscopy, assessment of changes in cell morphology during cultivation, and the results of testing the action of sera by the intensity of respiration of free and immobilized cells under the action of inhibitors. CONCLUSION: As a result of the experiments, the influence of the type of serum on the initiation of cell expansion from primary explants and further cell proliferation in vitro was established. Hypoxia during exposure of primary explants enhances the expansion of cells from tissue fragments of Whartons jelly tissue.

Non-healing ulcers pose a serious problem for public health due to the high cost of treatment, prolonged disability of patients, and low efficacy of therapy. They are the leading cause of non-traumatic lower limb amputations. The development of innovative bioengineering products is a significant step in the treatment of non-healing diabetic foot ulcers. One such product is a tissue-engineered acellular product made from highly regenerative human umbilical cord biomaterial. It contains growth factors, cytokines, and components of the extracellular matrix of Wharton’s jelly, which accelerates wound healing. THE AIM of this clinical study is to evaluate the safety and efficacy of a tissue-engineered acellular product from Wharton’s jelly of the umbilical cord for the treatment of chronic non-healing lower limb ulcers in patients with diabetic foot syndrome. RESULTS: a 60-year-old woman diagnosed with type 2 diabetes mellitus had chronic ulcers that had not responded to standard treatment for more than a year and a half. She was observed for 4 weeks in August 2024. As a result of the local application of an acellular product from human umbilical cord, signs of reduction in wound size and their complete healing were noted 4 weeks after the start of observation. CONCLUSION: clinical observation has demonstrated the safety and efficacy of the acellular product from human umbilical cord for the treatment of chronic non-healing ulcers of diabetic origin.