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  • Author or Editor: Attila Virág x
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Abstract

A single tooth from the locality of Üröm-hegy (Hungary) was designated as the holotype specimen of “Archidiskodon meridionalis ürömensis” by Vörös (1979). The observed morphology of the tooth, with a minimum of 15 molar plates (most likely 17) led to the conclusion that this specimen belongs to Mammuthus trogontherii rather than a subspecies of M. meridionalis. On the basis of rodent biostratigraphy a date in the region of MIS 19-17 seems likely (i.e. c. 0.8 Ma — c. 0.7 Ma). Taking into account the meridionalis-like enamel thickness (3.1 to 3.4 mm, mean 3.2 mm) as well as the intermediate or slightly advanced relative crown height (1.65) and lamellar frequency (6), the specimen shows mosaic morphology, which fits well in the framework of the contemporaneous European mammoth-bearing localities (e.g. Voigtstedt). Taking all the evidence together it seems that this molar is not only a misinterpreted specimen, but a representative of a very important period of mammoth evolution in Eurasia, when M. meridionalis and M. trogontherii occurred together in Europe and when the genetic mixing between the adjacent populations resulted in a hybrid zone, which was responsible for mosaic or intermediate individuals, such as the holotype of “Archidiskodon meridionalis ürömensis”.

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Ukraine belongs among those young countries where the beginnings of democratisation and nation-building approximately coincided. While the development of nation states in Central Europe was usually preceded by the development of nations, the biggest dilemma in the Ukraine is whether a nation-state programme — parallel to the aim of state-building — is able to bring unfinished nation-building to completion. Ukraine sways between the EU and Russia with enormous amplitude. The alternating orientation between the West and the East can be ascribed to superpower ambitions reaching beyond Ukraine. Eventually, internal and external determinants are intertwined and mutually interact with one another. The aim of the paper is to explain the dilemmas arising from identity problems behind the Ukraine’s internal and external orientation.

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Abstract

A total of 1,514 fossil bones were studied from the Vaskapu II rock shelter (Bükk Mountains, North Hungary). The objective of this study was to investigate those processes of bone modification that were important in the dispersal, destruction and preservation of bone in the deposit. Size-selective taphonomic processes were detected in the accumulation of vertebrate remains. The fossils were transported by water through a 15 m high fissure system above the locality during repeated precipitation and thawing. Size-sorting of the bones occurred within the fissures. During this process the fossils were damaged and fragmented and the remains were eventually emplaced into the Vaskapu II rock shelter. The size-sorting is statistically established by a method based on the chisquare test. This method clearly describes the differences between the life and death assemblages.

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For over half a decade, Syria, one of the key states in the Middle Eastern region has been experiencing turmoil. Many consider ethnic and religious differences as the main source of the confl ict. While this starting point is correct, analysts have failed to emphasize the energy confl icts in the background of the international and regional frontlines. The paper aims to investigate the energy related motivations of the most important regional and global actors amidst the confl ict in Syria.

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Authors: Trudy Scalise, Andrea Győrffy, István Tóth, Dávid Kiss, Virág Somogyi, Gréta Goszleth, Tibor Bartha, László Frenyó and Attila Zsarnovszky

Oestrogen (E2) and thyroid hormones (THs) are key regulators of cerebellar development. Recent reports implicate a complex mechanism through which E2 and THs influence the expression levels of each other’s receptors (ERs and TRs) to precisely mediate developmental signals and modulate signal strength. We examined the modulating effects of E2 and THs on the expression levels of their receptor mRNAs and proteins in cultured cerebellar cells obtained from 7-day-old rat pups. Cerebellar granule cell cultures were treated with either E2, THs or a combination of these hormones, and resulting receptor expression levels were determined by quantitative PCR and Western blot techniques. The results were compared to non-treated controls and to samples obtained from 14-day-old in situ cerebella. Additionally, we determined the glial effects on the regulation of ER-TR expression levels. The results show that (i) ER and TR expression depends on the combined presence of E2 and THs; (ii) glial cells mediate the hormonal regulation of neuronal ER-TR expression and (iii) loss of tissue integrity results in characteristic changes in ER-TR expression levels. These observations suggest that both E2 and THs, in adequate amounts, are required for the precise orchestration of cerebellar development and that alterations in the ratio of E2/THs may influence signalling mechanisms involved in neurodevelopment. Comparison of data from in vitro and in situ samples revealed a shift in receptor expression levels after loss of tissue integrity, suggesting that such adjusting/regenerative mechanisms may function after cerebellar tissue injury as well.

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Authors: Virág Somogyi, Tamás L. Horváth, István Tóth, Tibor Bartha, László Vilmos Frenyó, Dávid Sándor Kiss, Gergely Jócsák, Annamária Kerti, Frederick Naftolin and Attila Zsarnovszky

Thyroid hormones (THs) and oestrogens are crucial in the regulation of cerebellar development. TH receptors (TRs) mediate these hormone effects and are regulated by both hormone families. We reported earlier that THs and oestradiol (E2) determine TR levels in cerebellar cell culture. Here we demonstrate the effects of low concentrations (10–10 M) of the endocrine disruptor (ED) bisphenol A (BPA) on the hormonal (THs, E2) regulation of TRα,β in rat cerebellar cell culture. Primary cerebellar cell cultures, glia-containing and glia-destroyed, were treated with BPA or a combination of BPA and E2 and/or THs. Oestrogen receptor and TH receptor mRNA and protein levels were determined by real-time qPCR and Western blot techniques. The results show that BPA alone decreases, while BPA in combination with THs and/or E2 increases TR mRNA expression. In contrast, BPA alone increased receptor protein expressions, but did not further increase them in combination with THs and/or E2. The modulatory effects of BPA were mediated by the glia; however, the degree of changes also depended on the specific hormone ligand used. The results signify the importance of the regulatory mechanisms interposed between transcription and translation and raise the possibility that BPA could act to influence nuclear hormone receptor levels independently of ligand–receptor interaction.

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