Over the past two decades, developments in the field of nanobiomedicine have come a long way despite the unresolved hindrances. The creation and development of effective theranostic agents based on nanomaterials are urgent needs of modern medicine. Upconversion nanoparticles (UCNP) appear to be the most promising agents for developing theranostics due to their unique optical properties. There has been extensive research on new approaches to obtain stable colloids capable of prolonged circulation in the bloodstream, particularly with bovine serum albumin (BSA). The present work contributes to solving the problem of obtaining stable agents based on UCNP by coating water-soluble UCNPNOBF4 with a stable protein corona layer of BSA. The assembled nanocomplex is promising for usage as a diagnostic agent and is set for further investigation.
|The Assembly оf а Photoluminescent Nanocomplex Based оn Upconversion Nanoparticles.pdf||487.42 KB|
Methylation of DNA cytosine bases is a key epigenetic modification that plays an important role in the regulation of gene expression and the formation of the epigenome. Numerous studies of the human genome show that there is a close relationship between DNA methylation, age and sex of a person. Until now, the popular model has been the linear change in the methylation level with age. Here we find a fundamentally different DNA methylation behavior, namely the nonlinear dependence of the methylation level on age. We identify CpG probes whose methylation changes exponentially with age or according to a power law, and perform Gene Ontology enrichment analysis of the latter. Our results are relevant to understanding how DNA methylation changes with age and the found nonlinear CpG sites can be used to construct new epigenetic clocks.
|DNA Methylation in Aging- Beyond the Linear Processes.pdf||729 KB|
3D bioengineering constructs are currently a promising area of research in the regeneration of various tissues. In our work, several modifications of scaffolds based on hyaluronic acid glycidyl methacrylate are presented. Scaffolds have been tested for biocompatibility with nerve cells in an in vivo model of traumatic brain injury. Throughout the experiment, the neurological status of the animals was monitored, and at the end, a histological examination of the brain was carried out. It has been shown that scaffolds are non-toxic to nerve cells and reduce the development of neurological deficit in animals in the post-traumatic period. The possibility of using the scaffold with a lower biodegradation rate as a carrier of a therapeutic drug has also been demonstrated.
Decellularized matrices of animal organs can serve as a promising platform for creating highly relevant threedimensional in vitro models of tumor growth. In this work, the applicability of two decellularization protocols for obtaining the extracellular matrices of various murine organs was examined. The resulting decellularized matrices were characterized by visual integrity and preservation of the tissue architectonics. A high degree of the cellular component elimination was demonstrated while maintaining the basic structures of the extracellular matrix. From the point of view of convenience and ease of use, as well as the quality of the obtained matrices, the method based on the use of detergent sodium dodecyl sulfate and trypsin-aprotinin complex has demonstrated the greatest suitability. In the future, the developed protocol will be used to study tumor-matrix interaction and tissue-specific characteristics of growth and morphology of tumor cells.
An experimental trauma was performed for the studying of morphological changes characteristics of the brain under the action of neuroprotectors soon after the brain injury. The closed craniocerebral injury was modeled by the free fall of a load on the parietooccipital area of the brain. We made repeat studies of the influence of succinate medicaments (cytoflavin and mexicor) on histological examination and morphometric analysis of the microcirculatory bed of the cerebral cortex. The experiments were made on the 1st, 3rd, 7th, and 12th day after the traumatic brain injury. An experimental morphological study has established that the use of neuroprotetors after the trauma recovers of brain tissue and positively affects the angio- and cytoarchitectonics of the cerebral cortex in the posttraumatic period.
|Morphological Disturbances of Brain Structures in Traumatic Brain Injury.pdf||1.05 MB|
ADHD is considered one of the most common neurobehavioral disorders of childhood and among the most prevalent chronic health conditions affecting school-age children. This makes research of psychophysiological correlates of ADHD very important. The aim of our pilot study was to find out the specific aspects of autonomic regulation of a sensorimotor activity in children with ADHD. To assess objectively the functional state dynamics of the children, the technology of event-related telemetry of the heart rate was used (cogni-nn.ru, Lobachevsky State University). This technology integrates the ApWay.ru Web platform for the controlled activation of primary cognitive functions. The conducted study allowed us to reveal some specific aspects of sensorimotor activity and autonomic regulation for children with ADHD. A digital map of psychophysiological status based on the integration of indicators of sensorimotor activity and event-related parameters of autonomic regulation can be an effective tool to increase the specificity, sensitivity and reliability of the diagnosis of ADHD in children.
|Heart and Mind Interaction for ADHD.pdf||642.68 KB|
The development of clinical forms of infection and endoscopic changes in the gastric mucosa depends on the H.pylori genetic diversity in a given region. The aim of this work was to study the relationship of the genetic profile of H.pylori pathogenicity factors with clinical and endoscopic features of Helicobacter-associated gastritis in Nizhny Novgorod. A number of H.pylori pathogenicity genes of DNA isolates obtained by endoscopy from 151 patients with chronic H.pylori-associated gastritis (non-destructive, erosive, and atrophic) were studied by PCR. Results. In destructive processes in the gastric mucosa, the detection frequency of cagA, vacA s1 m1 genes and a combination of several pathogenicity factors, including iceA A1 and babA was higher than in other forms of gastritis. Atrophic gastritis is characterized by the genetic profile cagA and vacA s2 m2. Infection with several H.pylori strains is determined more often in erosive gastritis and atrophy of the gastric mucosa. Conclusions. In chronic gastritis in Nizhny Novgorod, a predominantly "European" character of the pathogen population structure was revealed - with a moderate content of the most pathogenic cagA, vacA s1-positive strains. Colonization of the gastric mucosa by H.pylori with a genetic structure containing pathogenicity factors cagA, vacA, babA, ice A2, in chronic H.pylori-associated diseases, it is a factor in increasing the severity, activity and prevalence of the inflammatory process, the appearance of signs of atrophy of the gastric mucosa. The greatest influence on these indicators is exerted by the presence of cagA and vacA s1 in the microorganism genome, as well as a combination of several pathogenicity factors.
|Genetic Variants of H.pylori in Different Forms of Chronic Gastritis.pdf||474.77 KB|
Genomic instability is one of the biomarkers of aging. Studies show that the spontaneous level of chromosomal aberrations in lymphocytes increases with age. However, it is not yet fully understood whether there is an agedependent increase in genomic instability. The aim of this study was to establish the patterns of the influence of age on the level of chromosomal aberrations in human lymphocytes. For this purpose, the spontaneous frequency of chromosomal aberrations, mitotic activity and the number of aneuploidies in the lymphocytes of centenarians (people over 85 years old) were assessed. A standard cytogenetic research method was used. It was shown that the overall frequency of chromosomal aberrations in peripheral blood lymphocytes in centenarians was significantly higher than in the control group. It was revealed that there is a decrease in the mitotic activity of lymphocytes in the sample of centenarians, while the level of aneuploidies corresponds to the control group. It was also found that, despite the fact that the total number of aberrations increases with age, a decrease in the frequency of deletions is observed in the group of centenarians. No correlation was found between biological age and the frequency of aberrations.
|Features of Karyotype Changes in Centenarians.pdf||398.86 KB|
The research of stress reaction under the influence of bee venom and immobilization on rat is made in this paper. It is demonstrated that the stress reaction is developed under the influence of both factors. However, it’s shown that the second phase of stress reaction connected with hypothalamo-pituitary-adrenal axis activation and glucocorticoid concentration increase predominates in case of bee venom injection. The revealed prolongation of the second, compensatory phase may define the organism resistance increase after the bee venom injection and bee venom therapeutic action.
|The Particularities of Organism Stress Reaction Development under the Influence of Bee Venom.pdf||610.34 KB|
The possibility of using laser interference microscopy to explore the morphological and functional state of erythrocytes was studied. The possibilities of this method based on the rapid determination of the structure and physiological state of erythrocytes were shown. The analysis of erythrocytes by laser interference microscopy showed that erythrocytes have a typical biconcave discocyte shape. On erythrocytes’ surface, there is a slight heterogeneity due to the presence of membrane-bound proteins. The impact on erythrocytes of stress hormones caused changes in erythrocyte surface that were different from physiologically normal. Numerous loosening of the structure appeared on cell surface during erythrocyte incubation with cortisol. Incubation of cells with adrenaline caused a greater effect of erythrocyte membranes deformation which was expressed by the appearance of convex seals and spicules on the surface. The molecular mechanisms of membrane modifications arising under the action of adrenaline and cortisol were discussed. The results of the work may be interesting both for basic research of erythrocyte properties and for practical medicine.
|Research of Erythrocytes Membranes Change by Laser Interference Microscopy.pdf||691.41 KB|