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3462. CARM1 modulators affect epigenome of stem cells and change morphology of nucleoli

Creator:
Franek, M., Legartová, S., Suchánková, J., Milite, C., Castellano, S., Sbardella, G., Stanislav Kozubek, and Bártová, E.
Format:
print, bez média, and svazek
Type:
article, články, model:article, and TEXT
Subject:
Fyziologie člověka a srovnávací fyziologie, buňky, ekologická genetika, cells, ecological genetics, epi-drugs, histones, epigenetics, ES cells, iPS cells, nucleoli, 14, and 612
Language:
English
Description:
CARM1 i nteracts with numerous transcription factors to mediate cellular processes, especially gene expression. This is important for the maintenance of ESC pluripotency or intervention to tumorigenesis. Here, we studied epigenomic effects of two potential CARM1 m odulators: an activator (EML159) and an inhibitor (ellagic acid dihydrate, EA). We examined nuclear morphology in human and mouse embryonic stem cells (hESCs, mESCs), as well as in iPS cells. The CARM1 modulators did not function similarly in all cell type s. EA decreased the levels of the pluripotency markers, OCT4 and NANOG, particularly in iPSCs, whereas the levels of these proteins increased after EML159 treatment. EML159 treatment of mouse ESCs led to decreased levels of OCT4 and NANOG, which was accomp anied by an increased level of Endo -A. The same trend was observed for NANOG and Endo -A in hESCs affected by EML159. Interestingly, EA mainly changed epigenetic features of nucleoli because a high level of arginine asymmetric di- methylation in the nucleoli of hESCs was reduced after EA treatment. ChIP -PCR of ribosomal genes confirmed significantly reduced levels of H3R17me2a, in both the promoter region of ribosomal genes and rDNA encoding 28S rRNA, after EA addition. Moreover, EA treatment changed the nuclear pattern of AgNORs (silver -stained nucleolus organizer regions) in all cell types studied. In EA -treated ESCs, AgNOR pattern was similar to the pattern of AgNORs after inhibition of RNA pol I by actinomycin D. Together, inhibitory effect of EA on arginine methylation and effect on related morphological parameters was especially observed in compartment of nucleoli., M. Franek, S. Legartová, J. Suchánková, C. Milite, S. Castellano, G. Sbardella, S. Kozubek, E. Bártová., and Obsahuje bibliografii
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

3463. Carnap and Newton: two approaches to the method of theory construction (Part I)

Creator:
Hanzel, Igor
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
Carnap, Hempel, Standard Conception of Scientific Theories, Newton, Principia, and cyclical method of theory construction
Language:
Slovak
Description:
The paper compares Carnap’s and Hempel’s Standard Conception of Scientific Theories with Newton’s method of theory construction as applied in his Principia. It is shown that the latter is built, contrary to Carnap’s and Hempel’s views, by a cyclical method., Příspěvek porovnává Carnapovu a Hempelovu standardní koncepci vědeckých teorií s Newtonovou metodou konstrukce teorie, jak je aplikován v jeho Principii. To je ukazováno že latter je postaven, na rozdíl od Carnap je a Hempel pohledy, cyklickou metodou., and Igor Hanzel
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

3464. Carnap and Newton: two approaches to the method of theory construction (Part II)

Creator:
Hanzel, Igor
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
Newton’s method of theory construction, method of measures, and meaning change of the term ''harmonic law''
Language:
Slovak
Description:
The paper, as a continuation of the paper Hanzel (2009), provides a methodological generalization of Newton’s method of theory construction as applied in Book I and Book III of his Principia. It reconstructs also the method of measures applied in those books. Finally, it shows how the term ''harmonic law'' changes its meaning in the Principia., Příspěvek, jako pokračování článku Hanzel (2009), poskytuje metodologickou zobecnění Newtonovy metody teorie konstrukce, jak je aplikováno v knize I a knize III jeho Principia. Rekonstruuje také metodu opatření uplatňovanou v těchto knihách. Nakonec ukazuje, jak pojem ,,harmonické právo'' mění svůj význam v Principii., and Igor Hanzel
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

3465. Carnapova modální logika C

Creator:
Punčochář, Vít
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
Carnap, modal logic, logic C, logic S5, possible worlds, and substitution
Language:
Slovak
Description:
In this paper, we present Carnap’s modal logic C, which is one of the first attempts to use the concept of possible world (that of state description in the Carnapian original terminology) in shaping the semantics for modalities. Some older technical results, which concern the logic C, are summarized, namely two different kinds of axiomatization of C, one unusual characterization of C as the only set of formulae having one special property, and semantical and syntactical relations of C to S5. The fact that C is not closed under the universal substitution is shortly discussed. Finally, the predicate version of C, which is not axiomatizable, is defined., V tomto příspěvku prezentujeme Carnapovu modální logiku C, která je jedním z prvních pokusů o využití konceptu možného světa (státního popisu v karnapské původní terminologii) při formování sémantiky modalit. Jsou shrnuty některé starší technické výsledky, které se týkají logiky C, a to dva různé druhy axiomatizace C, jedna neobvyklá charakterizace C jako jediná množina vzorců s jednou speciální vlastností a sémantické a syntaktické vztahy C až S5. Krátce je diskutována skutečnost, že C není uzavřena pod univerzální substitucí. Nakonec je definována predikátová verze C, která není axiomatizovatelná., and Vít Punčochář
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

3466. Carnitine pretreatment can partially change the excitability of the immature nervous tissue

Creator:
Dana Marešová, Hana Rauchová, and Kateřina Jandová
Format:
print, bez média, and svazek
Type:
article, články, model:article, and TEXT
Subject:
Fyziologie člověka a srovnávací fyziologie, epileptické záchvaty, epileptic seizures, carnitine treatment, hypobaric hypoxia, neuronal excitability, rat, 14, and 612
Language:
English
Description:
The possible protective action of L-carnitine on neuronal excitability was studied in 21-day-old male Wistar rats with implanted electrodes. Administration of L-carnitine did not change the elicitation and duration of the epileptic seizures (cortical afterdischarges, ADs) in rats under normobaric oxygen atmosphere conditions. However, in animals exposed to 30 min hypobaric hypoxia the duration of the ADs was shortened after the second, fourth and sixth stimulation (in comparison with the first evoked ADs) while carnitine-treated rats retained their neuronal excitability and the duration of ADs was shortened only after the third stimulation., D. Marešová, H. Rauchová, K. Jandová, I. Valkounová, J. Koudelová, S. Trojan., and Obsahuje bibliografii
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

3469. Carotenoid composition and photochemical activity of four sandy grassland species

Creator:
Veres, S., Tóth, V. R., Láposi, R., Oláh, V., Lakatos, G., and Mészáros, I.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
dry mass, photochemical efficiency, photosystem 2, seasonal changes, and xanthophyll cycle
Language:
Multiple languages
Description:
The photosynthetic pigments and photochemical efficiency of photosystem 2 (PS2) were studied in four constitutive species (Achillea millefolium L., Festuca pseudovina Hack. ex Wiesb., Potentilla arenaria Borkh., and Thymus degenianus Lyka) of a semiarid grassland in South-eastern Hungary. Every species displayed typical sun-adapted traits and substantial plasticity in the composition and functioning of the photosynthetic apparatus. The contents of chlorophylls (Chls) and carotenoids (Cars) on a dry matter basis declined from May to July, however, the amount of total Cars on a Chl basis increased. This increase was the largest in Potentilla (48 %) and the smallest in Achillea (14 %). The pool of xanthophylls (VAZ) was between 25 % and 45 % of the total Car content and was larger in July than in May. The content of β-carotene increased by July, but lutein content did not change significantly. The Chl fluorescence ratio Fv/Fm was reduced by 3-10 % at noon, reflecting the down-regulation of PS2 in the period of high irradiance and high temperature. The occurrence of minimal values of ΔF/Fm' showed close correlation to the de-epoxidation rate of violaxanthin. Hence in natural habitats these species developed a considerable capacity to dissipate excess excitation energy in the summer period in their photosynthetic apparatus through the xanthophyll cycle pool and a related photoprotective mechanism, when the photochemical utilization of photon energy was down-regulated. and S. Veres ... [et al.]
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

3470. Carotenoid composition of peridermal twigs does not fully conform to a shade acclimation hypothesis

Creator:
Levizou, E., Petropoulou, Y., and Manetas, Y.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
Arbutus, chlorophylls, leaves, Pistacia, Populus, Prunus, Quercus, sun/shade acclimation, twig internal microenvironment, and xanthophyll cycle
Language:
Multiple languages
Description:
The photosynthetic pigments of twigs in five tree and shrub species possessing chlorenchyma under a well developed, stomata-less, and highly photon absorptive periderm were analysed and compared to those of the corresponding canopy leaves. We asked whether the unavoidable shade acclimation of corticular chlorenchyma results in photosynthetic pigment complements typically found in shade leaves. As expected, chlorophyll (Chl) a/b ratios in twigs were consistently low. However, carotenoid (Car) analysis did not confirm the initial hypothesis, since twigs generally contained increased Chl-based pool sizes of the xanthophyll cycle components. The contents of photo-selective neoxanthin and lutein were high as well. Yet, β-carotene content was extraordinarily low. In addition, twigs retained high pre-dawn ratios of the deepoxidized antheraxanthin and zeaxanthin, although environmental conditions were not pre-disposing for such a state. The unexpected Car composition allows the conclusion that other micro-environmental conditions within twigs (hypoxia, increased red to blue photon ratios, and extremely high CO2 concentrations) are more important than shade in shaping the Car profiles. and E. Levizou, Y. Petropoulou, Y. Manetas.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

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