Sox9-Meis1 Inactivation Is Required for Adipogenesis, Advancing Pref-1+ to PDGFRα+ Cells.

Adipocytes arise from the commitment and differentiation of adipose precursors in white adipose tissue (WAT). In studying adipogenesis, precursor markers, including Pref-1 and PDGFRα, are used to isolate precursors from stromal vascular fractions of WAT, but the relation among the markers is not known. Here, we used the Pref-1 promoter-rtTA system in mice for labeling Pref-1+ cells and for inducible inactivation of the Pref-1 target Sox9. We show the requirement of Sox9 for the maintenance of Pref-1+ proliferative, early precursors. Upon Sox9 inactivation, these Pref-1+ cells become PDGFRα+ cells that express early adipogenic markers. Thus, we show that Pref-1+ cells precede PDGFRα+ cells in the adipogenic pathway and that Sox9 inactivation is required for WAT growth and expansion. Furthermore, we show that in maintaining early adipose precursors, Sox9 activates Meis1, which prevents adipogenic differentiation. Our study also demonstrates the Pref-1 promoter-rtTA system for inducible gene inactivation in early adipose precursor populations

REFUSAL TO COMMUNICATE AS A POSITIVE AND NEGATIVE COMMUNICATION STRATEGY

The paper has an overall focus on the refusal to communicate, which naïve language users would often interpret as “zero communication”. This aspect of human interaction has not yet been thoroughly investigated, which accounts for the novelty of the research. The paper analyses reasons for the refusal to communicate, its types, strategies, positive and negative effects, as well as verbal and nonverbal ways of its expression. The study uses a mixed-method research design based on observation, discourse analysis and method of introspection. The material of the research includes 389 acts of refusal to communicate selected from real-life or Internet conversations, fiction of the late 20th – early 21st centuries, and films in English and in Russian. All the communicative acts are investigated along the following lines: a) reasons; b) types; c) communication strategies; d) functions and e) forms of linguistic expression of refusal to communicate. We identify regularities and classify our data within each of the devised categories. The paper argues that refusal to communicate, which in fact manifests the intention to terminate communication, is part and parcel of human interaction possessing strong pragmatic, functional and emotional value. Though it is generally seen as a negative communication strategy, this study shows that under certain circumstances it can also have a positive effect on the outcome of interaction

A comparative study of hydrophilic phosphine hexanuclear rhenium cluster complexes’ toxicity

Octahedral rhenium cluster compound Na2H8[{Re6Se8}(P(C2H4CONH2)(C2H4COO)2)6] has recently emerged as a very promising X-ray contrast agent for biomedical applications. However, the synthesis of this compound is rather challenging due to difficulty to control the hydrolysis of initial P(C2H4CN)3 ligand during the reaction process. Therefore, in this report we compare the in vitro and in vivo toxicity of Na2H8[{Re6Se8}(P(C2H4CONH2)(C2H4COO)2)6] with those of related compounds featuring fully hydrolysed form of the phosphine ligand, namely Na2H14[{Re6Q8}(P(C2H4COO)3)6] (Q = S or Se). Our results demonstrate that cytotoxicity and acute in vivo toxicity of the complex Na2H8[{Re6Se8}(P(C2H4CONH2)(C2H4COO)2)6] solutions were considerably lower than those of compounds with fully hydrolysed ligand P(C2H4COOH)3. Such behavior can be explained by the higher osmolality of Na2H14[{Re6Q8}(P(C2H4COO)3)6] versus Na2H8[{Re6Se8}(P(C2H4CONH2)(C2H4COO)2)6]

The Study of Adipose Tissue Differentiation and Development

AbstractThe Study of Adipose Tissue Differentiation and DevelopmentbyOlga GulyaevaDoctor of Philosophy in EndocrinologyUniversity of California, BerkeleyProfessor Hei Sook Sul, ChairTwo functionally different adipose tissues exist in mammals: white (WAT) and brown(BAT). WAT is the primary energy storage site and a critical organ for regulation ofenergy metabolism through secretion of various adipokines. In contrast, BAT is a keythermogenic organ, capable of burning chemical substrates for heat generation throughunique protein UCP1. Interestingly, UCP1 is only expressed in brown or beigeadipocytes found in WAT, however all the transcriptional activators of UCP1 promoteridentified by far are not tissue-specific and, therefore, cannot solely explain BAT-specificexpression of UCP1. BAT is believed to form early in embryogenesis from muscle-likeprogenitors, while WAT depending on the anatomical locations, develops in lateembryogenesis or postnatally from non-muscle–like progenitors. Although embryogenicBAT precursors have been well characterized, the molecular identity of WAT precursorsremains controversial. The aim of this dissertation work was to identify novel tissuespecifictranscriptional regulator of UCP1 in BAT as well as to identify and characterizeWAT precursors at various stages of adipogenic commitment and differentiation.Chapter 1 reviews developmental origin of adipose tissue. Most of subcutaneous WATdepots develop perinatally, while visceral WAT develops postnatally from adiposeprecursors expressing markers such as Myf5, Pref-1, Wt1, and Prx1 depending on theanatomical location. BAT develops in early embryogenesis form Myf5+, Pax7+ musclelikeprecursors. Brown fat-like cells found in WAT upon cold exposure or b3-adrenergicstimulation may arise from transdifferentiation of white adipocytes or by de-novodifferentiation of yet to be characterized precursors. Finally, transcriptional andepigenetic control of brown and beige adipocyte differentiation is discussed.Chapter 2 demonstrates my efforts to characterize the hierarchy of adipose progenitorsin WAT in vivo. By using Pref-1 promoter-mediated conditional ablation of Sox9, one ofPref-1 targets in inhibiting adipogenesis, coupled with fluorescent labeling, I identifiedand characterized a population of early adipose progenitors that express Pref-1, Sox9and CD24. This early WAT precursor population is highly proliferative and does not yetexpress adipogenic markers and rather resembles stem cell-like population. Sox9appeared to be critical for maintaining these early precursors in highly proliferative andundifferentiated state. Loss of Sox9 in Pref-1+ cells lead to a depletion of this precursorpopulation and an increase in more committed PDGFRa+ preadipocytes that do notproliferate and express early adipogenic markers. This switch in precursor populationsfrom Pref-1+ to PDGFRa+ in the absence of Sox9 leads to enhanced adipogenesis andincreased adiposity impairing insulin sensitivity in vivo.Chapter 3 describes a role of novel BAT-enriched transcription factor, Zfp516 inregulating UCP1 transcription and BAT differentiation and development. I found thatZfp516 is induced upon cold exposure and directly binds and activates UCP1 andPGC1a promoters. I also showed that knockdown of Zfp516 in cultured cells impairsBAT-gene program and induces muscle-like gene signature. Thus, total body Zfp516KO mice exhibit severe defect in BAT development, while transgenic miceoverexpressing Zfp516 in all adipose tissues show increased browning of WAT. Thisleads to improved cold tolerance and reduces body weight accumulation upon high fatdiet improving metabolic parameters.Chapter 4 focuses on my efforts to identify Zfp516 interacting partners for activationBAT-gene program resulting in discovery of lysine-specific demethylase 1, Lsd1, as adirect binding partner of Zfp516. Lsd1 through interaction with Zfp516 is recruited toUCP1 and PGC1a promoters to demethylate H3K9 and therefore promotertranscription. Lsd1 is induced during BAT differentiation and its ablation using Myf5-Creresults in impaired embryonic BAT development. UCP1-Cre mediated ablation of Lsd1impairs BAT gene program and results in formation of BAT that resembles WAT,therefore reducing thermogenic capacity and causing obesity in mice. Lastly, Zfp516-Lsd1 interaction is required for Lsd1 function for BAT gene program in vitro.Supplement summarizes my effort to identify a novel gene critical for BAT function andcharacterizes one such gene, C11orf54. I found that C11orf54 is highly expressed inmurine BAT, kidney and liver and is highly induced during BAT cell line differentiation.C11orf54 is localized to the nucleus and cytoplasm and appears to be important for BATdifferentiation as CRISPR-mediated KO lines demonstrate dramatically impairedadipogenic differentiation. Overexpression of C11 in Cos7 cells results in increasedformation of TAG through yet-to be identified mechanism.Finally, chapter 5 summarizes my work describing importance of novel genes identifiedfor BAT and WAT development, future directions and remaining questions.Thus, these studies provide a better understanding of how BAT and WAT developmentand differentiation are regulated in vivo, as well as explain the hierarchy of adiposeprogenitors with various degree of commitment and differentiation in WAT

A public debt: its essence, impact on economy and redemption possibilities

An essence of public debt is reviewed in this article along with its impacts (good and bad) on economy and society of borrowing countries. Evolution of main indicators of public debt in certain countries is analyzed in this article. Authors also review public loan’s redemption possibilities. Governments had to attract free capital of other business entities and citizens to satisfy various public needs and to cover its expenditures. Public debt together with taxes Financial climate of any country, its development possibilities are defined by such indicators as public budget, deficit and, of course public debt, which is an aggregate indicator of both budget and deficit. Nowadays this problem becomes more and more important in the view of global economic crisis. A purpose of this research is to define essence and economic impacts of public debt and its redemption possibilities. The following tasks were set to reach these goals: to specify economic essence of public debt, to show pros and cons of public debt for social and economic activities; to analyze certain countries’ public debt’s evolution; to review its redemption possibilities. The economic point of view is that «A public debt is a system of monetary relations that cause redistribution of free capital of residents, non-residents, foreign countries and international monetary funds that transfer to debts aiming at public needs’ satisfaction». Nowadays public debt’s increase is reviewed as a condition of economic growth. A public debt provides government’s ability to solve social-economic problems. A public debt can have positive or negative impact on the country. The amount of the public debt can be analyzed together with the other indicators, such as GDP, for example. This indicator show an ability to cover the debt with the output produced in the country for a period. The main point is that a growth rate of the GDP should be higher than a growth rate of GDP. A public debt is a normal thing for modern countries according to world public borrowing practice. Nevertheless it shows a difference between country’s economic potential and society’s needs. The amount of a public debt of modern countries increases annually, and nowadays full redemption of this debt is unreal grace to its size, so it becomes virtual. That’s why many country-borrowers try not to become bad debtors. Their main method is to mobilize their efforts to internal economic growth, namely to cut budgetary expenditures, to rationalize import, to diverse economic potential, to improve efficiency of external borrowing, etc. At the same time we must admit that mutual obligations of different countries are stimulating economic growth and enlarge international cooperation

Replication Data for: RUSSIAN IMAGES OF THE EUROPEAN UNION: BEFORE AND AFTER MAIDAN

This articles probes into scope conditions for image change, investigating what changes in Russian images of the European Union (EU) have taken place as a result of the Russian-Ukrainian crisis. The crisis, a catalytic event, has been surrounded by uncertainty and strong emotions and is seen as a potential historical watershed in EU-Russian relations. The article examines Russia’s images of the EU’s intentions (good or bad?), capabilities (strong or weak?), and cultural and political status (inferior or superior?); and how they change in connection with the Russian-Ukrainian crisis. The article compares EU images across time found in Russian major newspapers and public opinion (studies undertaken in 2011-12 and 2015, before and after the crisis)