Polycaprolactone Nanofibers Functionalized by Fibronectin/Gentamicin and Implanted Silver for Enhanced Antibacterial Properties, Cell Adhesion, and Proliferation.

Novel nanomaterials used for wound healing should have many beneficial properties, including high biological and antibacterial activity. Immobilization of proteins can stimulate cell migration and viability, and implanted Ag ions provide an antimicrobial effect. However, the ion implantation method, often used to introduce a bactericidal element into the surface, can lead to the degradation of vital proteins. To analyze the surface structure of nanofibers coated with a layer of plasma COOH polymer, fibronectin/gentamicin, and implanted with Ag ions, a new X-ray photoelectron spectroscopy (XPS) fitting method is used for the first time, allowing for a quantitative assessment of surface biomolecules. The results demonstrated noticeable changes in the composition of fibronectin- and gentamicin-modified nanofibers upon the introduction of Ag ions. Approximately 60% of the surface chemistry has changed, mainly due to an increase in hydrocarbon content and the introduction of up to 0.3 at.% Ag. Despite the significant degradation of fibronectin molecules, the biological activity of Ag-implanted nanofibers remained high, which is explained by the positive effect of Ag ions inducing the generation of reactive oxygen species. The PCL nanofibers with immobilized gentamicin and implanted silver ions exhibited very significant antipathogen activity to a wide range of Gram-positive and Gram-negative strains. Thus, the results of this work not only make a significant contribution to the development of new hybrid fiber materials for wound dressings but also demonstrate the capabilities of a new XPS fitting methodology for quantitative analysis of surface-related proteins and antibiotics.

PRP of T2DM Patient Immobilized on PCL Nanofibers Stimulate Endothelial Cells Proliferation.

Diabetic foot ulcers (DFU) are a common complication of Type 2 Diabetes Mellitus (T2DM). Development of bioactive wound healing covers is an important task in medicine. The use of autologous platelet-rich plasma (PRP) consisting of growth factors, cytokines and components of extracellular matrix is a perspective approach for DFU treatment, but we previously found that some T2DM PRP samples have a toxic effect on mesenchymal stem cells (MSCs) in vitro. Here, we covalently immobilized T2DM PRP proteins on polycaprolactone (PCL) nanofibers, and the growth of endothelial cells on the PCL-COOH-PRP was investigated. Additionally, the level of NO reflecting the cytotoxic effects of PRP, angiogenin, and VEGF levels were measured in T2DM PRP samples. The results showed that the application of PCL-COOH-PRP nanofibers allows to remove the cytotoxicity of T2DM PRP and to improve endothelial cell adhesion and proliferative activity. We showed that the origin of T2DM PRP (the level of PRP toxicity or presence/absence of DFU) does not influence the efficiency of cell growth on PCL-COOH-PRP, and on the level of angiogenin, vascular epidermal growth factor (VEGF) in PRP itself.

Sex Differences in Liver, Adipose Tissue, and Muscle Transcriptional Response to Fasting and Refeeding in Mice.

Fasting is often used for obesity correction but the "refeeding syndrome" limits its efficiency, and molecular mechanisms underlying metabolic response to different food availability are under investigation. Sex was shown to affect hormonal and metabolic reactions to fasting/refeeding. The aim of this study was to evaluate hormonal and transcriptional responses to fasting and refeeding in male and female C57Bl/6J mice. Sex asymmetry was observed both at the hormonal and transcriptional levels. Fasting (24 h) induced increase in hepatic Fgf21 gene expression, which was associated with elevation of plasma FGF21 and adiponectin levels, and the upregulation of expression of hepatic (Pparα, Cpt1α) and muscle (Cpt1ß, Ucp3) genes involved in fatty acid oxidation. These changes were more pronounced in females. Refeeding (6 h) evoked hyperinsulinemia and increased hepatic expression of gene related to lipogenesis (Fasn) only in males and hyperleptinemia and increase in Fgf21 gene expression in muscles and adipose tissues only in females. The results suggest that in mice, one of the molecular mechanisms underlying sex asymmetry in hepatic Pparα, Cpt1α, muscle Cpt1ß, and Ucp3 expression during fasting is hepatic Fgf21 expression, and the reason for sex asymmetry in hepatic Fasn expression during refeeding is male-specific hyperinsulinemia.

Chromosomal evolution of Arvicolinae (Cricetidae, Rodentia). II. The genome homology of two mole voles (genus Ellobius), the field vole and golden hamster revealed by comparative chromosome painting.

Using cross-species chromosome painting, we have carried out a comprehensive comparison of the karyotypes of two Ellobius species with unusual sex determination systems: the Transcaucasian mole vole, Ellobius lutescens (2n = 17, X in both sexes), and the northern mole vole, Ellobius talpinus (2n = 54, XX in both sexes). Both Ellobius species have highly rearranged karyotypes. The chromosomal paints from the field vole (Microtus agrestis) detected, in total, 34 and 32 homologous autosomal regions in E. lutescens and E. talpinus karyotypes, respectively. No difference in hybridization pattern of the X paint (as well as Y paint) probes on male and female chromosomes was discovered. The set of golden hamster (Mesocricetus auratus) chromosomal painting probes revealed 44 and 43 homologous autosomal regions in E. lutescens and E. talpinus karyotypes, respectively. A comparative chromosome map was established based on the results of cross-species chromosome painting and a hypothetical ancestral Ellobius karyotype was reconstructed. A considerable number of rearrangements were detected; 31 and 7 fusion/fission rearrangements differentiated the karyotypes of E. lutescens and E. talpinus from the ancestral Ellobius karyotype. It seems that inversions have played a minor role in the genome evolution of these Ellobius species.

Chromosomal evolution of Arvicolinae (Cricetidae, Rodentia). I. The genome homology of tundra vole, field vole, mouse and golden hamster revealed by comparative chromosome painting.

Cross-species chromosome painting has become the mainstay of comparative cytogenetic and chromosome evolution studies. Here we have made a set of chromosomal painting probes for the field vole (Microtus agrestis) by DOP-PCR amplification of flow-sorted chromosomes. Together with painting probes of golden hamster (Mesocricetus auratus) and mouse (Mus musculus), the field vole probes have been hybridized onto the metaphases of the tundra vole (Microtus oeconomus). A comparative chromosome map between these two voles, golden hamster and mouse has been established based on the results of cross-species chromosome painting and G-banding comparisons. The sets of paints from the field vole, golden hamster and mouse identified a total of 27, 40 and 47 homologous autosomal regions, respectively, in the genome of tundra vole; 16, 41 and 51 fusion/fission rearrangements differentiate the karyotype of the tundra vole from the karyotypes of the field vole, golden hamster and mouse, respectively.

Spontaneously formed trans-anethol/water/alcohol emulsions: mechanism of formation and stability.

We studied the spontaneous emulsification and droplet growth mechanism in trans-anethol/water/ethanol solutions, also known as the beverage ouzo, using dynamic light scattering spectroscopy. This simple ternary mixture is a generic example of a system that forms microemulsions spontaneously when brought into the two-phase region. The volume fraction of the dispersed phase was found to profoundly affect the growth rates of the droplets, which is a new finding that has not been predicted by the Lifshitz-Slyozov-Wagner theory. Time-dependent measurements show that the droplet growth is governed by Ostwald ripening (OR), and no coalescence was observed. Furthermore, the OR rates increase with increasing oil concentration at low alcohol content. We attribute this behavior to enhanced droplet-droplet interactions. At high ethanol concentrations, we found that the measured rates decreased as the oil concentration increased. The OR growth mechanism completely correlates with changes in droplet size. The kinetics of droplet growth shows that the ripening has a saturation limit at a droplet radius of about 1.5 mum. Thus, formed emulsions remain stable for months.