Low-temperature barrier discharge plasma modification of scaffolds based on polylactic acid

We have explored the effect of low-temperature barrier discharge plasma treatment in oxygen, nitrogen, and argon on modification of the physicochemical properties of polylactic acid (PLA)-based scaffolds. The cellular-mediated immune response to the interaction of macrophages of three donors with the modified surface of PLA-based scaffolds was also nvestigated. Carbonization of the PLA surface accompanied by a carbon atomic concentration increase is shown to occur following plasma treatment. Argon plasma significantly affects the wettability characteristics of PLA; the hydrophilicity and lipophilicity are improved, and the surface energy is increased. The viability of cells in the presence of plasma-modified PLA scaffolds is lower than that for unmodified PLA but remains greater than that for the negative control. We find that PLA scaffolds do not cause increased expression of the proinflammatory (TNFα, IL-6, IL-1β) cytokines after 6 days of cell cultivation. At the same time, PLA scaffolds do not affect the increased production of anti-inflammatory cytokines (IL-10)

THE WORLD OF CHILDHOOD AND YOUTH IN RUSSIAN NOBLE FAMILIES OF THE FIRST HALF OF THE NINETEENTH CENTURY IN THE CONTEXT OF STRATIFICATION APPROACH

traditions. Hence, it is one of the criteria for evolutionary or revolutionary changes in a particular society, accentuating the culture of everyday life and the connection of generations. In a rigidly structured estate society, such as the population of the Russian Empire, the world of childhood and youth developed in the context of social traditionalism, adopted in one or another estate community. Methodology: The basis of the study is based on the principles of historicism, objectivity, and science. To prove these theses, comparative-historical, problem-chronological, logical-analytical methods were used, which made it possible to reliably reconstruct the world of childhood and youth in noble families of Russia of the first half of the nineteenth century. Result: The most detailed system of socialization of children and adolescents was developed in an environment of a noble family, distinguished by more strict and complex etiquette, where pride in belonging to a noble class was inculcated at an early age. But the feeling of belonging to the upper class among the young nobles was different and mediated by many factors, first of all, the ancient lineage, the level of the material wealth of the family, education, upbringing,  and culture. That is, the variability of the socialization of children and adolescents was extensive. Applications: This research can be used for universities, teachers, and students. Novelty/Originality: In this research, the model of The World of Childhood and Youth in Russian Noble Families of the First Half of the Nineteenth Century in the Context of Stratification Approach is presented in a comprehensive and complete manner

Immunomodulatory properties of composite materials based on polylactide and hydroxyapatite

In the present study composites based on polylactide and hydroxyapatite with the content of components 50:50 and 75:25 were investigated. Components were mixed at 40°C, which was followed by the sonication procedures and its precipitation in ethanol. The analysis of the following composite materials revealed that their chemicalcrystallographic characteristics of individual components remained intact after varying its dispersion and material crystallinity degree. Composite material of the ratio 75:25 were characterized by the lowest degree of crystallinity - 20.5% and the average crystallite size up to 28.8 nm showed an increased roughness and dispersive component of surface energy. In comparison to polylactide, the composite has a high capacity for osseointegration. In the paper, special attention is given to the immunomodulatory properties of composite materials. Assessment of the immune system cells showed that the macrophages are most viable in the presence of pure polylactide and composite 75/25. Intensive secretion of proinflammatory cytokines in macrophage cultures in vitro was not found at that

The balance of Polo-like kinase 1 in tumorigenesis

Polo-like kinase 1 (Plk1) belongs to a family of conserved serine/threonine kinases with a polo-box domain, which have similar but non-overlapping functions in the cell cycle progression. Plk1 plays a key role to ensure the normal mitosis. Interestingly, overexpression of Plk1 is associated with tumor development and could serve as a prognostic marker for many cancers. Due to Plk1 overexpression, several Plk1 inhibitors have been developed and tested for the cancer treatment. However, in a recent study, it has been suggested that down-regulation of Plk1 could also induce aneuploidy and tumor formation in vivo. Therefore, a normal level of Plk1 is important for mitosis. And caution should be taken when Plk1 inhibitors are used in the clinical trial and their side effects including tumorigenesis should be carefully evaluated

Surface Properties of Manganese(II) Carbonate

The energies of unoccupied and occupied orbitals have been used as correlation parameters between the electronic and adsorptive properties of organic molecules. A model describing the chemisorption of organic compounds on MnCO 3 was proposed. This involves three types of interaction: 1-, 2- and 3-electron donor–acceptor interaction between adsorbent and adsorbate frontier orbitals

Particularities of speech readiness for schooling in pre-school children having general speech underdevelopment: a social and pedagogical aspect

The relevance of the research is due to the necessity of creating the pedagogical conditions for correction and development of speech in children having the general speech underdevelopment. For them, difficulties generating a coherent utterance are characteristic, which prevents a sufficient speech readiness for schooling forming in them as well as successful socialization. With regard to this, the paper is aimed at finding out the particularities of coherent monologic and dialogical speech in senior pre-school children having the general speech underdevelopment. The leading method to studying this problem is experimental studying, which allows viewing the particularities of coherent dialogical and monologic speech in pre-schoolers having the general speech underdevelopment in an integrated way. The paper describes particularities of coherent monologic and dialogical speech in pre-school children having the general underdevelopment depending on the level of formation. The quantitative and qualitative analysis of the data obtained has shown that pre-school children having the general speech underdevelopment have significant difficulty carrying on a dialogue and making up detailed utterances. Examples of various lexical and grammatical, logical and meaning-related mistakes of the children are given. The materials of the paper may be of use for specialists rendering the psychological and pedagogical support for children having speech disorders in the educational process

Labor Strategies for Russian Youth

Based on empirical sociological studies, the article reflects dispositions, factorial models of choice, life strategies in the field of labor trajectories of modern Russian youth. The paper gives the author’s typology of labor and career orientations of young people which show the meaningfulness of career aspirations in the ranks of value dispositions. The primary life choices of young respondents in the field of career and labor decisions are outlined, the importance of career ladder in labor strategy for a fourth of the respondents is emphasized. The problems in the implementation of state youth policy, discrimination in labor activity, as well as the risks of migration behavior associated with failed expectations and requests to labor strategies of youth are stated.  The inconsistence associated with the transformation of views and attitudes of modern young people to measuring success of labor strategies, based on the construction of a risk map of Russian youth is stressed

Immunomodulatory properties of composite materials based on polylactide and hydroxyapatite

In the present study composites based on polylactide and hydroxyapatite with the content of components 50:50 and 75:25 were investigated. Components were mixed at 40°C, which was followed by the sonication procedures and its precipitation in ethanol. The analysis of the following composite materials revealed that their chemicalcrystallographic characteristics of individual components remained intact after varying its dispersion and material crystallinity degree. Composite material of the ratio 75:25 were characterized by the lowest degree of crystallinity - 20.5% and the average crystallite size up to 28.8 nm showed an increased roughness and dispersive component of surface energy. In comparison to polylactide, the composite has a high capacity for osseointegration. In the paper, special attention is given to the immunomodulatory properties of composite materials. Assessment of the immune system cells showed that the macrophages are most viable in the presence of pure polylactide and composite 75/25. Intensive secretion of proinflammatory cytokines in macrophage cultures in vitro was not found at that

Nitrogen Plasma Treatment of Composite Materials Based on Polylactic Acid and Hydroxyapatite

The effect of surface modification by an arc discharge plasma in a nitrogen flow with treatment durations of 5 and 10 min on the physicochemical properties and biocompatibility of the surface of composites based on polylactic acid and hydroxyapatite (PLA/HA) with different mass ratios (80/20, 70/30, 60/40) has been investigated. The aim of this work was to show the correlation between the changes of the physicochemical characteristics (chemical compound, morphology, wettability) of the surface layer of the PLA/HA composites and the cell viability (macrophages) in the presence of the plasma-modified materials. The dependence of alterations of the functional properties (wettability, biocompatibility) on the change in the chemical composition under the plasma exposure has been established. The chemical composition was studied using X-ray photoelectron spectroscopy (XPS), the surface morphology was researched with scanning electron microscopy (SEM), and the wettability of the composite’s surface was analyzed by measuring the contact angle and surface energy calculation. In addition, the viability of macrophages was investigated when the macrophages from three donors interacted with a modified PLA/HA surface. It was found that the formation of the new functional groups, –C-N and N-C=O/C=O, improves the wettability of the surface of the composites and promotes the viability of macrophages in the presence of the composite materials. The fundamental principles for obtaining promising materials with the required properties for eliminating bone defects have been created