Соціальний контекст підготовки здобувача вченого ступеня у вищій школі України й США ( кейс-стаді)

Розглядається вплив нових умов модернізації життя на трансформацію соціального портрету майбутнього вченого в системі вищої школи України та США. Виокремлюються деякі найважливіші особливості підготовки здобувача вченого ступеня з суспільних і гуманітарних наук як результат традицій вищої школи. Загальне та особливе у підготовці здобувача вченого ступеня підтверджується даними кейс-стаді за матеріалами американського та українського університетів. The article deals with the influence of new conditions of life modernization in society on transformation of social portrait of a future scientist in higher education system of Ukraine and the USA. Some important peculiarities in preparation of seekers of scientific degree in social sciences and humanities as the result of higher education traditions are singled out. General and specific in preparation of a scientific degree-seeker is confirmed by data of case study of American and Ukrainian Universities

Political science for medical students: a tutorial for the course in Political Science for the School of Medicine

Розміщено вступ до навчального посібника англійською мовою.This English-language tutorial presents the most important topics of political science, introducing students to this discipline’s basic categories and to the development of political processes in society thus contributing to the formation of the world outlook of future medics. The tutorial is designated to deepen students’ knowledge of chosen topics and can be used for self-study in preparation for practical classes in political science

Mitochondrial malfunction mediates impaired cholinergic Ca2+ signalling and submandibular salivary gland dysfunction in diabetes

Xerostomia (dry-mouth syndrome) is a painful and debilitating condition that frequently occurs in individuals with diabetes and is associated with impaired saliva production and salivary gland hypofunction. Saliva fluid production relies on Ca2+-coupled secretion driven by neurotransmitter stimulation of submandibular acinar cells. Although impairments in intracellular Ca2+ signalling have been reported in various xerostomia models, the specific Ca2+-dependent mechanisms underlying saliva fluid hypofunction in diabetes remain unclear. In this study, we show that diabetic animals exhibit severe xerostomia, evident by reduced saliva flow rate, diminished total protein content, and decreased amylase activity in the saliva secreted by submandibular glands. These impairments remained resistant to exogenous cholinergic stimulation. In submandibular acinar cells in diabetes, the intracellular Ca2+ signals evoked by cholinergic stimulation were reduced and delayed, caused by malfunctioning mitochondria. Upon initiation of cholinergic-evoked Ca2+ signals, mitochondria accumulate higher Ca2+ and fail to redistribute Ca2+ influx and facilitate the store-operated Ca2+ entry effectively. Structural damage to mitochondria was evident in the acinar cells in diabetes. These findings provide insights into the potential targeting of malfunctioning mitochondria for the treatment of diabetic xerostomia as an alternative strategy to the existing pharmacotherapeutic approaches

Isolation of Neural Stem Cells from the embryonic mouse hippocampus for in vitro growth or engraftment into a host tissue

For both stem cell research and treatment of the central nervous system disorders, neural stem/progenitor cells (NSPCs) represent an important breakthrough tool. In the expanded stem cell-based therapy use, NSPCs not only provide a powerful cell source for neural cell replacement but a useful model for developmental biology research. Despite numerous approaches were described for isolation of NSPCs from either fetal or adult brain, the main issue remains in extending cell survival following isolation. Here we provide a simple and affordable protocol for making viable NSPCs from the fetal mouse hippocampi, which are capable of maintaining the high viability in a 2D monolayer cell culture or generating 3D neuro-spheroids of cell aggregates. Further, we describe the detailed method for engraftment of embryonic NSPCs onto a host hippocampal tissue for promoting multilinear cell differentiation and maturation within endogenous environment. Our experimental data demonstrate that embryonic NSPCs isolated using this approach show the high viability (above 88%). Within a host tissue, these cells were capable of differentiating to the main neural subpopulations (principal neurons, oligodendrocytes, astroglia). Finally, NSPC-derived neurons demonstrated matured functional properties (electrophysiological activity), becoming functionally integrated into the host hippocampal circuits within a couple of weeks after engraftment

Optimized Model of Cerebral Ischemia In situ for the Long-Lasting Assessment of Hippocampal Cell Death

Among all the brain, the hippocampus is the most susceptible region to ischemic lesion, with the highest vulnerability of CA1 pyramidal neurons to ischemic damage. This damage may cause either prompt neuronal death (within hours) or with a delayed appearance (over days), providing a window for applying potential therapies to reduce or prevent ischemic impairments. However, the time course when ischemic damage turns to neuronal death strictly depends on experimental modeling of cerebral ischemia and, up to now, studies were predominantly focused on a short time-window—from hours to up to a few days post-lesion. Using different schemes of oxygen-glucose deprivation (OGD), the conditions taking place upon cerebral ischemia, we optimized a model of mimicking ischemic conditions in organotypical hippocampal slices for the long-lasting assessment of CA1 neuronal death (at least 3 weeks). By combining morphology and electrophysiology, we show that prolonged (30-min duration) OGD results in a massive neuronal death and overwhelmed astrogliosis within a week post-OGD whereas OGD of a shorter duration (10-min) triggered programmed CA1 neuronal death with a significant delay—within 2 weeks—accompanied with drastically impaired CA1 neuron functions. Our results provide a rationale toward optimized modeling of cerebral ischemia for reliable examination of potential treatments for brain neuroprotection, neuro-regeneration, or testing neuroprotective compounds in situ

Comparative analysis of algorithms calculating distances of DNA sequences and some related problems

The main focus of this article is to describe our original approach to compare the quality of defined metrics on the set of DNA sequences. The approach is based on the fact, that the triples of distances between genomes should ideally form isosceles acute triangles. On the basis of this assumption, we proposed value of the norm, gives in practice aссeptable results. In the course of work on the implementation of algorithms have been carried out computational experiments with 100 DNA of “distant” species, as well as with representatives of several genomes of great apes and humans.The reported study was funded by RFBR according to the research project № 16-47-630829

Satellite microglia display spontaneous electrical activity uncorrelated with activity of the attached neuron

Microglia are innate immune cells of the brain. We have studied a subpopulation of microglia, called satellite microglia. This cell type is defined by a close morphological soma-to-soma association with a neuron, indicative of a direct functional interaction. Indeed, ultrastructural analysis revealed closely attached plasma membranes of satellite microglia and neurons. However, we found no apparent morphological specializations of the contact and biocytin injection into satellite microglia showed no dye-coupling with the apposed neuron or any other cell. Likewise, evoked local field potentials or action potentials and postsynaptic potentials of the associated neuron did not lead to any transmembrane currents or non-capacitive changes in the membrane potential of the satellite microglia in the cortex and hippocampus. Both satellite and non-satellite microglia, however, showed spontaneous transient membrane depolarizations which were not correlated with neuronal activity. These events could be divided into fast and slow rising depolarisations, which exhibited different characteristics in satellite and non-satellite microglia. Fast and slow rising potentials differed with regard to voltage dependence. The frequency of these events was not affected by application of TTX, but fast rising event frequency decreased after application of GABA. We conclude that microglial cells show spontaneous electrical activity uncorrelated with the activity of adjacent neurons

Algorithm of realization of the problem of double-arc welding with coated electrodes of different types

In the article the algorithm of realization of a problem of two-arc welding by the covered electrodes of different types is considered. When burning two welding arcs from electrodes of different composition into one welding bath, we change the chemical composition of the deposited metal. Thus, without creating new electrodes, we obtain the required chemical composition of the weld metal and weld. The study of the possibility of obtaining samples for the analysis of the chemical composition of the deposited metal, an arc of indirect action. This method can reduce the cost of welding materials in the process of obtaining samples, as well as reduce the complexity and energy intensity of the work

Some new heuristic algorithms in analysis of the similarity of DNA-sequences

This paper describes algorithms, corresponding computer programs and the results of computations, supplementing results published earlier. We consider the multiple sequence alignment problem, which can be nominated by a central problem in computational biology. For it, we continue to consider some different versions of socalled “triangular norm” defined on the set of triangles formed by the different distance between genomes computed by different algorithms. Basically, the new results are associated with incorrect variants of obtaining the triangle inequality, which for matrices of the order of about 50 × 50 is violated in the two most successful metrics (including the Panin’s metric earlier developed by us) in less than 1% of cases. Possible improvements are related to the use of neural networks that were not used by us in previous calculations. In this case, neural networks solve the inverse problem: we improve (reduce) the overall badness of the matrix of distances between genomes, forcibly changing the previously obtained distances; further, we try to reflect these forced changes in the original algorithms for calculating distances. In this paper, we present the results of concrete calculations obtained by us.The authors of the article express their gratitude to Vladislav Dudnikov (Togliatti State University, Russia) for his help in preparing this paper. The reported study was partially supported by RFBR according to the research project No. 16-47-630829