Article is focused on environmental scanning electron microscopy as a universal method for investigation of insulating and water containing samples. Advantages of this microscopy method are demonstrated by experiments that study biological tissues of fossil insects embedded in amber or analyze morphological structure of root canal walls prepared by laser. and Článek se zabývá environmentální rastrovací elektronovou mikroskopií jako univerzální metodou pro zkoumání izolačních vzorků a vzorků obsahujících vodu. Výhody této mikroskopické metody jsou presentovány na základě experimentů zabývajících se studiem zbytků biologických tkání fosilního hmyzu v jantaru a studiem povrchu stěny kořenových kanálků zubů po preparaci pevnolátkovým laserem.
The dental pulp represents an easily acces-sible source of adult dental pulp stem cells (DPSCs). The preferred approach to DPSC isolation is enzymatic digestion. However, the duration of the enzymatic activity is crucial. The purpose of this study was to isolate the DPSC populations using this method, characterize their biological properties and proliferation capacity, and to determine their ability to differentiate into mature cells. Before enzymatic
digestion using 0.05% trypsin, we used the homogenization method in order to obtain a fine homogenate from the solid pulp tissue. The stem cells were cultivated in modified cultivation medium for mesenchymal adult progenitor cells containing 2% foetal bovine serum, growth factors and insulin-transferrin-
selenium supplement. We were successfully able to isolate 10 populations of DPSCs. The vitality of DPSCs did not drop below
90 %. However, the DPSCs showed a significant decrease in the relative telomere length number with increasing passaging (P < 0.05). Isolated DPSCs highly expressed the CD markers: CD29, CD44, CD90, CD13, CD73 and CD166. In contrast, CD markers CD31, CD106, CD34 and CD45 were negative or low positive. We confirmed the high osteogenic and chondrogenic potential of the isolated stem cells. Isolated DPSCs did not show signs of cell degeneration or spontaneous differentiation during the entire cultivation. In addition, we were able to shorten the enzyme activity duration, and we were the first to demonstrate trypsin as the enzyme used for the enzymatic digestion method with the viability over 90 % of isolated DPSCs using this method. and Corresponding author: Nela Pilbauerová
This article considers the fiction of Vítězslav Nezval (1900–1958), which, incomparison with his verse, sometimes seemed to represent a marginal area ofhis work. The lyrical quality of some of his fiction was also emphasized. Thoughthese texts do not constitute an absolute dissolution of the story into lyric verse,they do reveal a number of features of the traditional epic model, which Nezval,however, uses in new contexts, with new functions. The key point is the framelikenature of the fictional world, which oscillates between the “possible” and“impossible.” Subsequently there is a considerable increase in the role of theswitching mechanism from level to level of the text structure, and in the role of the narrator, who highlights the two fundamental levels. A stream of associationsthen moves to the foreground, often expressed in distinctively stylized poeticlanguage. On the other hand, apart from the well-known and often-noted analogieswith the work of Proust, one finds in Nezval’s fiction a number of intertextualreferences to the tradition of the novel from Flaubert to Meyerink; above all it isthe strong, evident inspiration of Trivialliteratur. Nezval, however, employing theschematic approaches of Trivialliteratur, plays a game, often verging on parodyand the absurd, and principally, maintaining tension between verisimilitude andfantasy. This dualism, on the boundary between reality and fiction, to which thereader is led and where the action takes place and the characters move, seems to bea fundamental feature of Nezval’s epic model. and Studie se zabývá prózou Vítězslava Nezvala, která ve srovnání s poesií zdánlivě představovala okrajovou oblast autorovy tvorby; lyričnost také byla zdůrazňována jako klíčový prvek Nezvalova prozaického umění. Příslušné texty přesto nejsou absolutním rozplynutím příběhu v lyrice a vykazují dokonce řadu rysů tradičního epického modelu; Nezval ovšem tyto prvky používá v nových souvislostech a s novými funkcemi. Klíčovým bodem je rámcová povaha fikčního světa, kolísajícího mezi „možným“ a „nemožným“ pólem. Následně zásadně vzrostla role přepínačů mezi jednotlivými vrstvami textové struktury a zároveň i role vyprávěče, který zaujímá pozici reflektoru mezi oběma základními rovinami. Do popředí pak vystupuje proud asociací, vyjadřovaných často osobitě stylizovaným básnickým jazykem. Na druhou stranu lze v Nezvalových prózách – kromě známých a mnohokrát evidovaných analogií s texty Proustovými - nalézt řadu intertextuálních odkazů k románové tradici od Flauberta k Meyerinkovi; silná a zjevná je ale především inspirace triviální literaturou: Nezval ovšem hraje se schematickými postupy pokleslých žánrů hru, která je často dovádí na okraj parodie, stupňuje do absurdity a především udržuje „dvojlomné“ napětí mezi věrohodností a fantastičností příběhu. Ona podvojnost na rozhraní reality a fikce, na kterém je veden čtenář, odehrávají se děje a na němž se pohybují jednající postavy, se zdá být základním rysem Nezvalova epického modelu.
IFN-γ is a pleiotropic cytokine crucial for both innate and adaptive immunity, which also plays a critical role in immunological surveillance of cancer. Genetic defects or gene silencing in the IFN-γ signal transduction pathways as well as in the expression of IFN-γ-regulated genes represent frequent mechanisms by which tumour cells can escape from immune responses. Epigenetic control of the IFN-γ signalling pathway activation associated with epigenetic changes in the corresponding regulatory gene regions, such as chromatin remodelling, histone acetylation and methylation, and DNA demethylation is frequently dysregulated in tumour cells. Epigenetic silencing of the IFN-γ regulatory pathway components, as well as of the IFN-γ-regulated genes crucial for tumour cell recognition or induction of anti-tumour immune responses, has been documented in various cancer models. Expression of both IFN-γ signalling pathway components and selected IFN-γ-regulated genes can be influenced by epigenetic modifiers, namely DNA methyltransferase and histone deacetylase inhibitors. These agents thus can mimic, restore, or boost the immunomodulatory effects of IFN-γ in tumour cells, which can contribute to their anti-tumour therapeutic efficacies and justifies their potential use in combined epigenetic therapy with immunotherapeutic approaches. and Corresponding author: Milan Reiniš
The incidence of metabolic syndrome increases in the developed countries, therefore biomedical research is focused on the understanding of its etiology. The study of exact mechanisms is very complicated because both genetic and environmental factors contribute to this complex disease. The ability of environmental fac tors to promote phenotype changes by epigenetic DNA modifications (i.e. DNA methylation, histone modifications) was demonstrated to play an important role in the development and predisposition to particular symptoms of metabolic syndrome. There is no doubt that the early life, such as the fetal and perinatal periods, is critical for metabolic syndrome development and therefore critical for prevention of this disease. Moreover, these changes are visible not only in individuals exposed to environmental factor s but also in the subsequent progeny for multiple generations and this phenomenon is called transgenerational inheritance. The knowledge of molecular mechanisms, by which early minor environmental stimuli modify the expression of genetic information, might be the desired key for the understanding of mechanisms leading to the change of phenotype in adulthood. This review provides a short overview of metabolic syndrome epigenetics., J. Kuneš, I. Vaněčková, B. Mikulášková, M. Behuliak, L. Maletínská, J. Zicha., and Obsahuje bibliografii