Yulia Gordeeva

Introduction. Traumatic brain injury (TBI) is one of the main causes of mortality and disablement in humans and animals worldwide. Early assessment of TBI severity enables reducing deferred adverse effects and mortality. However, implementation of artificial intelligence (AI) technologies in clinical practice is hindered due to the shortage of qualified personnel and lack of specialized datasets in blood cytology. The aim of the study is to analyse changes in cellular composition of peripheral blood in mice after severe TBI and to create a dataset of blood smears to be used in AI algorithms. Materials and М ethods. The study was conducted at Don State Technical University in the period from November to December 2025. The objects for the study were images of the peripheral blood smears obtained from mice with TBI: blood samples from the caudal vein were collected, and smears were prepared and digitized. Image labeling was performed using the PULLAR platform (a development of “MedTsifra” Research Laboratory, Rostov-on-Don). Results. A dataset of TBI blood smears was created, and 60 images containing neutrophils, monocytes, and lymphocytes were labeled. Elevated counts of segmented neutrophils and monocytes indicate the development of the acute inflammatory response in traumatic brain injury condition. A decrease in lymphocyte count is consistent with the data about reduction of the lymphocyte numbers at the early TBI stages and indicates the state of immunosuppression. Discussion and Conclusion. The obtained data demonstrate the informative value of the peripheral blood cell composition analysis in mice with traumatic brain injury, which confirms the potential of developing and implementing AI technologies for improving the quality of diagnostics and automating the routine tasks.

Severe traumatic brain injury (TBI) is one of the leading causes of mortality and disability worldwide. To date, there are no clinically effective neuroprotective agents. Biomaterials that combine structural support for damaged tissue with a depot for therapeutic agents may represent a key solution to this problem. To evaluate the neuroprotective potential of a collagen matrix derived from the jellyfish Rhizostoma pulmo (R. pulmo) and modified with sodium thiosulfate (Na₂S₂O₃) as an hydrogen sulfide (H₂S) donor in a bioengineered platform for the treatment of severe TBI. Comprehensive characterization of the collagen matrix (electrophoresis, fluorescence microscopy), its implantation in a mouse model of severe TBI, and subsequent morphological, histological, ultrastructural, and immunohistochemical analyses of connexin 43 (Cx43) and p53 protein (p53) were performed. In addition, molecular dynamics simulations of the interactions between sulfur-containing compounds and target proteins were conducted. The effects were compared with inhibition of endogenous H₂S synthesis using aminooxyacetic acid (AOAA). The collagen matrix retains the properties of type I collagen and forms a three-dimensional porous structure with high hydrophilicity and biocompatibility. Implantation ensures effective defect filling, reduces cystic degeneration, and preserves cortical structure. Modification with Na₂S₂O₃ results in a significant reduction in both nuclear and cytoplasmic accumulation of p53, prevention of Cx43 dysregulation, a decrease in the proportion of damaged neurons and inflammatory infiltration, and preservation of tissue ultrastructure. In contrast, inhibition of CBS with AOAA exacerbates pathological changes. Molecular modeling demonstrated that S₂O₃²⁻ is capable of forming stable electrostatic interactions with domains of p53 and Cx43 under conditions of acidosis and elevated Ca²⁺. A collagen matrix derived from R. pulmo and modified with Na₂S₂O₃ represents a promising biodegradable platform that combines structural support with local H₂S-dependent regulation of key mechanisms of secondary brain injury. This approach provides a multilevel neuroprotective effect and opens new opportunities for the development of therapeutic implants for severe TBI.

Background: Connexins (Cx) are a family of transmembrane proteins that form gap junctions and connexin hemichannels (HCs), enabling direct intercellular communication within the nervous system. Connexin 43 (Cx43), the principal astrocytic connexin, exhibits a context-dependent dual role: under physiological conditions it maintains tissue homeostasis and metabolic support, whereas under pathological conditions excessive activation of Cx43 hemichannels promotes neuroinflammation, excitotoxicity, blood–brain barrier disruption, and secondary neural tissue damage. Other connexin isoforms also contribute to the pathogenesis of neurological and psychiatric disorders through alterations in neuronal synchronization, glial signaling, and myelin integrity. Objective: To systematize current evidence on the role of key connexin isoforms in acute nervous system injuries—including stroke, traumatic brain injury, spinal cord injury, and peripheral nerve injury—as well as chronic disorders such as neurodegenerative diseases, epilepsy, and psychiatric disorders, with particular emphasis on the functional duality of connexin channels and the therapeutic potential of their selective modulation. Methods: A systematic literature search was conducted in the PubMed, Scopus, and Web of Science databases in accordance with the PRISMA framework and the PRISMA Extension for Scoping Reviews guidelines. The review included data from experimental models, postmortem brain studies, genetic association analyses, and pharmacological intervention studies. The retrieved studies were screened, assessed for eligibility, and integrated using a qualitative narrative synthesis approach. Results: In acute neural injuries, hyperactivation of Cx43 hemichannels amplifies inflammatory signaling, edema formation, and neuronal death, whereas selective HCs inhibitors reduce lesion volume and improve functional outcomes in experimental models. Connexin 36 (Cx36) contributes to cortical spreading depolarization and seizure propagation, while Connexin 32 (Cx32) and Connexin 47 (Cx47) are critically involved in oligodendrocyte function and white-matter demyelination. In PNI, Cx43 upregulation contributes to neuropathic pain, whereas mutations in Cx32 cause hereditary demyelinating neuropathies. In neurodegenerative diseases—including Alzheimer’s disease, Parkinson’s disease, and amyotrophic lateral sclerosis—Cx43 hemichannel activity promotes neuroinflammation and pathological protein accumulation, while reduced Cx32/Cx47 expression disrupts metabolic support of axons. In psychiatric disorders such as major depressive disorder, bipolar disorder, and schizophrenia, decreased astrocytic connexin expression (Cx43 and Cx30) has been associated with impaired glial–neuronal communication and cognitive–emotional dysfunction. In epilepsy, increased Cx43/Cx30 expression contributes to neuronal hypersynchronization and blood–brain barrier dysfunction, whereas selective hemichannel blockade suppresses seizure activity. Conclusions: Cx—particularly Cx43—occupies a central position in the molecular mechanisms of secondary neural injury and network dysfunction. The dual functional properties of gap junctions and hemichannels determine their context-dependent effects across neurological and psychiatric diseases. Selective inhibition of pathological HCs activity shows significant neuroprotective and anticonvulsant potential and represents a promising direction for the development of targeted therapeutic strategies. Further studies are required to determine optimal therapeutic time windows, tissue-specific effects, and the long-term safety of Cx modulation.

Collagen is a major extracellular-matrix protein widely used in regenerative medicine, yet conventional terrestrial sources raise biosafety and acceptability concerns, motivating the search for marine alternatives. This study evaluates the jellyfish Rhizostoma pulmo (R. pulmo) from the Azov Sea as a sustainable collagen source and assesses its suitability for biomedical materials. Acid-soluble collagen was extracted using 0.5 M acetic acid and purified by salt precipitation and dialysis, followed by physicochemical/structural characterization (sodium dodecyl sulfate–polyacrylamide gel electrophoresis (SDS–PAGE), Limulus amebocyte lysate (LAL) endotoxin testing, transmission electron microscopy (TEM), and immunofluorescence with type I collagen antibodies) and biological evaluation in vitro (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) cytotoxicity on MRC5 fibroblasts; adhesion and proliferation assays on HeLa cells). The extracted collagen showed a high yield (~26.2%), a type I-like electrophoretic profile with α-, β-, and γ-components, fibrillar ultrastructure by TEM, and positive type I collagen immunoreactivity; endotoxin levels were low (0.461 EU/µL), and no cytotoxicity was detected under the tested conditions. Porous collagen sponges/scaffolds were fabricated by lyophilization, displaying interconnected pores with an average size of ~80 µm and pH-dependent swelling, and they supported 3D cell growth and tumor-cell dissemination in an in vitro breast carcinoma scaffold model. Overall, Azov Sea R. pulmo collagen demonstrates promising structural quality, low endotoxin burden, and cytocompatibility, supporting its potential as a marine biomaterial for sponge/scaffold-based tissue engineering and wound-related applications.

The intensive application of antimicrobial agents in industrial poultry farming contributes to the formation and maintenance of an extensive resistome – the collection of antibiotic resistance genes within microbial communities. This review synthesizes current data on the structure, diversity, and circulation of antibiotic resistance genes in poultry production systems within the context of the “One Health” concept. It offers a unique, systemic perspective, viewing a poultry farm as an integrated ecosystem for the circulation of resistance genes. Metagenomic studies have revealed over 600 types of resistance genes in the poultry microbiome, conferring resistance to 25 classes of antibiotics. The most prevalent genes confer resistance to tetracyclines (tetA, tetB, tetM), β-lactams (blaTEM, blaCTX-M, blaCMY-2), macrolides (ermB, ermA), fluoroquinolones (qnrS, qnrB), and aminoglycosides. Of particular concern is the detection of carbapenemase genes (blaNDM, blaOXA-48) and genes conferring resistance to last-resort drugs such as tigecycline (tetX4) and colistin (mcr-1). The concentration of resistance genes in poultry litter can reach 10¹⁶ copies per gram, exceeding levels found in other types of livestock waste. The review details key ecological reservoirs, including the gut microbiome, hatcheries, biofilms in water systems, litter, and production surfaces. The primary dissemination mechanisms encompass vertical transmission via hatcheries, horizontal gene transfer mediated by plasmids and transposons, and large-scale dispersion through litter into agro-ecosystems. The role of co-selection with heavy metal and biocide resistance genes in maintaining the resistome in the absence of antibiotic pressure is highlighted. This review emphasizes the necessity for an integrated approach to resistome control. This includes optimizing antimicrobial use, enhancing biosecurity measures, developing alternative prophylactic strategies, and implementing effective waste management protocols to mitigate environmental and epidemiological risks.

This work introduces a novel and specialized dataset of high-resolution fluorescence microscopic images focused on astrocytic gap junctions, aiming to get insights into intercellular communication in both healthy and pathological brain conditions. The dataset includes 20 z-stack image series -- 10 from human glioblastoma tissue and 10 from healthy rat brain tissue -- each containing between 24 and 126 optical slices. These images were acquired using standardized protocols following immunofluorescence labeling with antibodies against connexin 43 (Cx43), enabling visualization of gap junction localization at the subcellular level. The dataset is uniquely tailored to support detailed morphological and quantitative analyses of gap junction networks, featuring metadata including species, age, sex, imaging parameters, tissue characteristics, and localization of gap junctions in images provided by bounding boxes and image masks. Its structure facilitates comparative studies across physiological states and species, enhancing translational and evolutionary perspectives on astrocytic connectivity. Given the labor-intensive nature of manual gap junction quantification and 3D statistical analysis for Z-stacks, this dataset serves as a resource for the development of machine learning tools capable of automating the detection and analysis of Cx43-positive signals.