59 research outputs found
Differentiation of mouse embryonic stem cells along a hepatocyte lineage
No full textThe development of implantable engineered liver tissue constructs, ex vivo hepatocyte based therapeutic devices and drug discovery studies are limited by an inadequate hepatocyte cell source. Embryonic stem (ES) cells, characterized by their self-renewing and multi-lineage differentiating capabilities, represent a promising mature cell source required for these applications. Previous research has utilized embryoid body (EB) formation in both guided, through extracellular matrix and growth factor supplementation, and unguided, or spontaneous, differentiation to generate hepatocyte like cells. However, these characterizations have been limited to only one or several lineage specific protein or gene expression patterns. In addition, there have been few reports of long term propagation or characterization of long term function for ES cell derived hepatocyte precursors. In this thesis, we have implemented a platform for the long term propagation and augmentation of functional hepatocytes generated from murine ES cell sources. We first utilize a controlled, reproducible, EB mediated differentiation system to characterize efficiency of hepatocyte lineage commitment in four parallel culture configurations. These studies have shown that, EB mediated stem cell differentiation spontaneously yield populations of hepatocyte lineage cells expressing mature hepatocyte markers such as albumin (ALB) and Cytokeratin 18 (CK-18). We then used secondary culture configurations to study the effects of collagen sandwich culture and Oncostatin-M (OSM) or S-nitroso-N-acetylpenicillamine (SNAP) supplementation of EB derived hepatocyte-lineage cell function. The results of these studies suggest that SNAP, independent of the collagen supplementation, maintains the highest levels of ALB expression, however mature liver specific CK-18 is only expressed in the presence of both gel sandwich culture supplemented with SNAP. In addition, albumin secretion and Cytochrome P450 detoxification studies indicated that this condition was the best for the augmentation of hepatocyte-like function. Maintenance and augmentation of hepatocyte-like cells isolated from heterogeneous EB cell populations will be a critical step in generating large numbers of functional differentiated cells for therapeutic use.Ph.D.Includes bibliographical references (p. 45-48)
Ethnic affiliation, common memory and traditional culture of Macedonian Muslims in Albania: adaptating and preserving the identity (fieldworks of 2008-2010)
No full textThe paper is devoted to the question of ethnic affiliation of Macedonian Muslims in conditions of combined ethnical neighborhood. There are around ten settlements with Macedonian population in the Eastern part of the Republic of Albania (Mac. Golo Brdo, Alb. Golloborda). Five scientific researchers from St. Petersburg: Andrej Sobolev, Alexander Novik, Denis Ermolin, Maria Morozova and Alexandra Dugushina (Institute of Linguistic Studies of the Russian Academy of Sciences, Peter the Great Museum of Anthropology and Ethnography and St. Petersburg State University) had organized fieldwork in the villages Trebisht, Klenje, Ostren etc. in 2008-2010. The author puts into academic context a new description of almost unexplored Macedonian community. The data have been obtained during the fieldworks in Eastern Albania. In conditions of long-term neighborhood with other languages and religious denominations, the adapting mechanisms have worked out specific approaches to preserving ethnical identity and traditional culture, perceiving their value and necessity of translating to descendants. Materials of fieldwork include data about identity, language, culture of Macedonian community in different periods of the state of Albania (Osmanli time, Royal Albania, Enver Hoxha monism period, post-communist transition, modern republic). These expedition materials are archived in the Kunstkamera (Museum of Anthropology and Ethnography of the Russian Academy of Sciences). The founds of the Museum have traditional clothes of Macedonian Muslims from Golo Brdo which are collected during the fieldworks 2008-201
Markers for an In vitro skin substitute
No full textThe tissue engineering self-assembly approach allows the production of skin substitutes comprising both the dermis and epidermis, using methods promoting the secretion and organization of a dense extracellular matrix by skin cells. In a reconstructed epidermis, all cellular layers of the native tissue are present. An evaluation of the expression and localization of a number of specific protein markers revealed that the self-assembled, tissue-engineered skin substitute shares some common features with normal human skin, such as the expression of Ki-67, keratins 10 and 14, filaggrin, involucrin, transglutaminase, DLK, a3-integrin subunit, laminin-S, and collagens I, II, 1V, and VII. At the ultrastructural level, many differentiation markers can be observed, including desmosomes, as well as an organized basement membrane presenting hemidesmosomes, lamina densa, and lamina lucida. In this chapter, protocols to generate skin substitutes by the self-assembly approach will be presented and the methods including the labeling of the principal skin differentiation markers by immunofluorescence will be examined.
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Long-term hepatitis B infection in a scalable hepatic co-culture system.
No full textVolume 8, Issue 1, 1 December 2017, Article number 125, pgs. 1-11. Authors: Benjamin Y. Winer, Tiffany S. Huang, Eitan Pludwinski, Brigitte Heller, Felix Wojcik, Gabriel E. Lipkowitz, Amit Parekh, Cheul Cho, Anil Shrirao, Thomas W. Muir (Tom W. Muir), Eric Novik & Alexander Ploss.Hepatitis B virus causes chronic infections in 250 million people worldwide. Chronic hepatitis B virus carriers are at risk of developing fibrosis, cirrhosis, and hepatocellular carcinoma. A prophylactic vaccine exists and currently available antivirals can suppress but rarely cure chronic infections. The study of hepatitis B virus and development of curative antivirals are hampered by a scarcity of models that mimic infection in a physiologically relevant, cellular context. Here, we show that cell-culture and patient-derived hepatitis B virus can establish persistent infection for over 30 days in a self-assembling, primary hepatocyte co-culture system. Importantly, infection can be established without antiviral immune suppression, and susceptibility is not donor dependent. The platform is scalable to microwell formats, and we provide proof-of-concept for its use in testing entry inhibitors and antiviral compounds.The lack of models that mimic hepatitis B virus (HBV) infection in a physiologically relevant context has hampered drug development. Here, Winer et al. establish a self-assembling, primary hepatocyte co-culture system that can be infected with patient-derived HBV without further modifications
Testing the 8-syndrome structure of the child behavior checklist in 30 societies
No full textThere is a growing need for multicultural collaboration in child mental health services, training, and research. To facilitate such collaboration, this study tested the 8-syndrome structure of the Child Behavior Checklist (CBCL) in 30 societies. Parents' CBCL ratings of 58,051 6- to 18-year-olds were subjected to confirmatory factor analyses, which were conducted separately for each society. Societies represented Asia; Africa; Australia; the Caribbean; Eastern, Western, Southern, and Northern Europe; the Middle East; and North America. Fit indices strongly supported the correlated 8-syndrome structure in each of 30 societies. The results support use of the syndromes in diverse societies.Masha Y. Ivanova; Thomas M. Achenbach; Levent Dumenci; Leslie A. Rescorla; Fredrik Almqvist; Sheila Weintraub; Niels Bilenberg; Hector Bird; Wei J. Chen; Anca Dobrean; Manfred Dpfner; Nese Erol; Eric Fombonne; Antnio Castro Fonseca; Alessandra Frigerio; Hans Grietens; Helga Hannesdttir; Yasuko Kanbayashi; Michael Lambert; Bo Larsson; Patrick Leung; Xianchen Liu; Asghar Minaei; Mesfin S. Mulatu; Torunn S. Novik; Kyung Ja Oh; Alexandra Roussos; Michael Sawyer; Zeynep Simsek; Hans-Christoph Steinhausen; Christa Winkler Metzke; Tomasz Wolanczyk; Hao-Jan Yang; Nelly Zilber; Rita Zukauskiene; Frank C. Verhuls
Изучение источников заражения цыплят-бройлеров сальмонеллами с использованием ERIC-ПЦР и реакции агглютинации с флюоресцентно-мечеными антигенами (ИРА)
No full textThe study aims to develop diagnostic algorithms for using ERIC-PCR and IRA, which make it possible to identify the routes of Salmonella introduction into a poultry farm. The authors studied the genetic differences of 15 isolates of Salmonella spp., isolated from pathological material, feed raw materials and swabs from poultry houses of broiler poultry farms (parent stock and replacement young animals) in the West Siberian region. The species of Salmonella cultures were confirmed by sequencing and using biochemical tests and agglutination sera. Bacterial DNA was isolated using the standard silicosorption method. Analysis of the genomic DNA of the studied collection of Salmonella using the ERIC-PCR method allowed us to group the resulting strains and isolates into three genotypes that differ in amplicon patterns on polyacrylamide gel electrophoresis. Comparison of IRA results with blood sera of birds from the parent flock and replacement young animals of poultry farm No. 1 made it possible to identify antibodies to both Salmonella genotype one and Salmonella genotype 2 in most of the examined poultry flocks. Analysis of the correlation of antibody titers to Salmonella antigens of the 1st and 2nd genotypes made it possible to exclude a cross-reaction in some poultry houses. The correlation was negative. It was positive in two poultry houses, and there was no correlation in one. The immunofluorescence agglutination reaction system makes it possible to precisely distinguish the seroprevalence of different Salmonella strains at individual agricultural enterprises. The totality of data from serological analysis suggests that some birds have an increased susceptibility to infection with Salmonella of both genotypes, which means that these individuals have genetic characteristics or characteristics of the intestinal microbiota associated with exposure to infection with Salmonella.Цель исследования — разработать диагностические алгоритмы использования ERIC-ПЦР и ИРА, которые позволят выявлять пути заноса сальмонелл на птицефабрику. Изучали генетические различия 15 изолятов Salmonella spp., выделенных из патологического материала, кормового сырья и смывов из птичников птицефабрик бройлерного направления (родительское стадо и ремонтный молодняк) Западно- Сибирского региона. Видовую принадлежность культур сальмонелл подтверждали методом секвенирования и/или с использованием биохимических тестов и агглютинационных сывороток. ДНК бактерий выделяли стандартным силико - сорбционным методом. Анализ геномной ДНК изучаемой коллекции сальмонелл методом ERIC-ПЦР позволил сгруппировать полученные штаммы и изоляты в три генотипа, отличающиеся друг от друга паттернами ампликонов на электрофорезе в полиакриламидном геле. Сопоставление результатов ИРА с сыворотками крови птицы родительского стада и ремонтного молодняка птицефабрики №1 позволило выявить антитела как к сальмонеллам генотипа 1, так и к сальмонеллам генотипа 2 в большинстве обследованных стад птицы. Анализ корреляции титров антител к антигенам сальмонелл 1-го и 2-го генотипов позволил исключить перекрестную реакцию, так как в отдельных птичниках корреляционная зависимость была отрицательной, в двух птичниках положительной и в одном птичнике отсутствовала. Система реакции иммунофлуоресцентной агглютинации позволяет достаточно специфично различать серопревалентность к разным штаммам сальмонелл на отдельно взятых сельскохозяйственных предприятиях. Совокупность данных серологического анализа позволяет говорить о том, что у части птицы наблюдается повышенная восприимчивость к заражению сальмонеллами обоих генотипов, что позволяет предполагать у данных особей наличие генетических особенностей или особенностей кишечной микробиоты, связанных с восприимчивостью к заражению сальмонеллами
Discourses of biopolitics and human security in the context of new challenges and threats to humanity
No full textThe research aims at explicating two discourses that are most important for solving global problems of humanity: biopolitics and human security. The similarity of the studied concepts is revealed. According to the authors, it consists in the sameness of their object, and the differences - in its interpretation. Biopolitics sees its interest in finding ways to control the impersonal “man in General”, and human security - in its individuation. The measure of correlation of these concepts and their relation to the philosophical discourse about freedom is revealed. The author traces the dialectics of biopolitics and human security, the moments when the biopolitical discourse of “insured” and “uninsured” life intersects with the “colonizing” discourse. It is concluded that the conflict of interests of the studied discourses is inevitable, none of them is able to “rise above the fray”, having the opportunity to answer complex questions of human security. The measure of their effectiveness as an intellectual tool and practical mechanism for solving problems is illustrated by “fragile States” (the case of sub-Saharan Africa) and in the context of the COVID-19 pandemic
Balkan Colonists in the Azov Region: Diversity of Identities and Demise of the Ethnic Paradigm
No full textThrough his work, the author analyzes the influence of state ideology and cultural codes on the ethnic and national self-identification of the migrants from Southeastern Europe to the Azov region of Russia. Through his research, he has revealed the degree of influence of various factors contributing to the sustainable preservation or loss of ethnic, regional, linguistic and religious identities within the framework of the development of a separate multi-ethnic territory. The source base for the study is the documents of the State Archive of the Rostov Region and the materials of complex expeditions, the Archive of the Museum of Anthropology and Ethnography of the Russian Academy of Sciences. The author comes to the conclusion, that at the present, most residents of the villages on the shores of the Taganrog Bay are well aware of the history of their settlements; many are ready to claim that they have Greek/ Arnaut roots, and therefore they resolutely declare their “autochthony.” However, there are no attempts to revitalize this traditional culture or it’s holidays - “like in Greece or Albania” (as it is happening in the Zaporozhye and Donetsk regions). In the region, belonging to one’s people, by those born and living there, is perceived as a more significant marker than ethnic origin, ethnic self-identification and declaration of ethnic preferences
Socio-humanitarian knowledge and education: development paradoxes / E. K. Novik
No full textРассматриваются проблемы развития системы образования в Республике Беларусь. Анализируются упущения и просчеты реформирования социального гуманитарного блока дисциплин, связанные с вступлением в болонский процесс, переходом к централизованному тестированию, модульной системе обучения. Внесены предложения по совершенствованию действующей системы высшего образования.The problems of the development of the education system in the Republic of Belarus are considered, omissions and miscalculations of the reform of the social humanitarian block of disciplines, connected with entering the Bologna process, the transition to centralized testing, the modular system of education are analyzed. The author makes proposals on improving the current system of higher education
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