Population Dynamics of MafA-Positive Cells During Ontogeny of Human Pancreas

© 2016, Springer Science+Business Media New York.Diverse transcription factors influencing cell differentiation are often chosen as markers of β cell progenitors. One of these transcription factors is MafA, which according to data in literature activates the expression of insulin gene in β cells. Other data support the hypothesis that MafA is required solely for the regulation of insulin secretion by β cells of adult islets and is not involved in the development of islet cells. In this paper, we study the role of MafA through both examination of human pancreas ontogeny and comparison of these data with dynamic changes in the population of insulin-positive and glucagon-positive cells. The aim of this research was the immunohistochemical analysis of MafA, insulin, and glucagon expression during human pancreas ontogeny. The research was conducted on whole embryos and isolated human fetal organs, obtained as a result of either miscarriage or legal medical abortion with voluntary consent of patients, and also on autopsy material from infant and adult human pancreas. As a result of this study, it was found that, during the ontogeny of human pancreas, the first MafA-positive cells appear in the islets at 12.5 weeks of gestation, that is, later than both insulin-positive cells (11.5 weeks of gestation) and glucagon-positive cells (8.5 weeks of gestation). No MafA-positive cells were found in the epithelium of pancreatic ducts. The number of MafA-positive cells in the islets increases during pancreatic organogenesis. The results of our research do not allow us to regard MafA as a marker of undifferentiated progenitors of islet cells. Based on this, we believe that the results obtained in this study are a supplementary contribution to the hypothesis that relates MafA to the markers of adult β cells

C-kit and desmin-positive cells in expression in islets of pancreas during alloxan diabetes in rats.

Nowadays there are findings that C-kit-positive and desmin-positive stellate cells help to regenerate endocrine part of pancreas. But still it is unknown about their role and the way of differentiation of these cells during pancreas regeneration. That's why the aim of our work was to study the dynamic of these cells population during alloxan diabetes in rats. The work was made on 33 rats with experimental diabetes. Blood glucose, insulin and glucagon levels were analyzed. Also the expression of desmin (marker of stellate cells), α-SMA (marker of myofibroblast), C-kit (marker of endocrine stem cells), insulin and glucagon (marker of differentiated α- And β-cells of Langerhans islets) was studied. The expression of desmin was found after one day of experimental diabetes in islets cells of pancreas. Maximum of these cells was after the third day of the experiment. Also after one day of the experiment C-kit-positive cells, which expressed insulin and glucagon were found. We suppose that stellate cells are the main factor of microenvironment for differentiation of C-kit-positive progenitor cells into β-cells through the stage of glucagon-positive cells because stellate pancreas cells can produce different growth factors and components of intercellular matrics. © Human stem cells institute, 2013

Realization of potential of enterprise structure development as the criterion of ensuring the object-differentiated approach to rendering the state support : the Russian Federation

The objective of the research. Undertaken in the conditions of an economic crisis and sanctions restrictions the attempts of system optimization of business activity state regulation in Russia still don't contribute to increase in business sector efficiency and to full accomplishment of all assigned social and economic functions. In the article the author rationalizes the point, assuming that in the basis of state regulation system the implementation level of entrepreneurial structure capacity, as the most adequate criterion of rendering the state support of business activity, which besides shall carry an object-differentiated nature, shall be laid. Short description of methodology. In the article authors offer an original interpretation of the concept "potential of enterprise structure development" and a method to calculate an indicator "the realization level of potential of enterprise structure development" as key criterion at realizing an object-differentiated approach to rendering the state support of enterprise structures. Compilation of the most important research results and their significance. In the article based on the formed differentiation criteria of measures of the state support of entrepreneurial structures authors offer the measures system differentiated on the bases of the implementation level of potential of entrepreneurial structures development and the importance of this structure in strategic priorities system of territorial development on preferential creation of institutional conditions for an entrepreneurship development; on internal capacity development of entrepreneurial structures; on direct support of business activity.peer-reviewe

Conditions for the formation of a non-autonomous phase at the structural deformation of complex vanadium oxides

Received: 02.03.2018. Accepted: 10.04.2018. Published: 10.05.2018.A new previously unknown effect of a reversible transition from a singlephase system to a heterophase system containing a non-autonomous phase was observed during thermal and chemical deformations of the Zn2–2xCd2xV2O7 structure.The role of local symmetry in the formation of the non-autonomous phase is shown on the basis of X-ray diffraction studies in situ and a comparative crystal-chemical analysis of the structural deformations of isoform monoclinic solid solutions of zinc and copper pyrovanadates with zero volumetric thermal expansion.The work was supported by UB RAS (project 18-10-3-32)

Structural and Functional Organization of the Vestibular Apparatus in Rats Subjected to Weightlessness for 19.5 Days Aboard the Kosmos-782 Satellite

The vestibular apparatus was investigated in rats subjected to weightlessness for 19.5 days. The vestibular apparatus was removed and its sections were fixed in a glutaraldehyde solution for investigation by light and electron microscopes. Structural and functional charges were noted in the otolith portions of the ear, with the otolith particles clinging to the utricular receptor surface and with the peripheral arrangement of the nucleolus in the nuclei of the receptor cells. It is possible that increased edema of the vestibular tissue resulted in the destruction of some receptor cells and in changes in the form and structure of the otolith. In the horizontal crista, the capula was separated

Integral assessment of the social and economic development of megacities in Russia

The relevance of the analyzed issue is due to the existing need for more attention to the problems of large cities, which are the social and economic centers that perform important functions and realize the interests of the population, business and local government. The purpose of this article is to disclose the sources of the urban growth and development, the integrated assessment of the size and spatial distribution of the economic activity, regional planning and the government activity. The leading approaches to the study of this issue are systemic and reproduction, which, along with the use of econometric modeling and statistical analysis, allowed revealing significant shortcomings of the institutional urban management mechanism and proposing a number of measures to correct these shortcomings. The article illustrates the theoretical basis of modeling of large cities as spatial economic systems, determines their sources of growth, gives the characteristic features of the urban development in modern conditions, and proposes a conceptual model of a modern city. The contents of the article may be useful for the development of social and economic development strategies both the urban district, and the region as a whole, since large cities act as a locomotive, and they move the regional economy in the direction of the social and economic well-being. © 2016 Malikh et al

Native and Activated Hepatic Stellate Cells Stimulate Liver Regeneration in Rats After Partial Hepatectomy and 2-Acetylaminofluorene Injection

© 2016, Springer Science+Business Media New York.One the current challenges of modern hepatology is to find new approaches to stimulate liver regeneration and to find new methods for liver disease treatment. Cell therapies, which are based on using regional stem cells for disease treatment, are under active development. However, studies, devoted to their transplantation, are currently scarce. In recent years, hepatic stellate cells are considered to be hepatic stem cells. It is known that activated hepatic stellate cells can transdifferentiate into myofibroblasts and lead to liver fibrosis. The aim of our work was to study the influence of native and activated hepatic stellate cells in vivo by lead nitrate injection after transplantation into partial hepatectomized rats, which is considered to be a classical model to study liver regeneration. Injection of 2-acetylaminofluorene (AAF), which selectively eliminates hepatocyte proliferation, was used to understand the hepatic stellate cells role in liver regeneration process better. Our results suggest that transplanted native and activated hepatic stellate cells can differentiate into hepatocyte-like cells and positively influence liver regeneration without inducing liver fibrosis