A hajdúszoboszlói Kéthalom recens löszvegetációjának fitolit morfotípus-diverzitás vizsgálata

A kunhalmok az alföldi táj kiemelkedő természetvédelmi és kultúrtörténeti értékei. Az intenzív mezőgazdaság elől a kunhalmok felszínére visszaszorult löszpusztai növényzet fitolitkészletét a Hajdúszoboszló melletti Kéthalmon vizsgáltuk. A halom növényzetének kevésbé degradált palástját a domináns pázsitfüvek alapján három részre osztottuk; ezeket cönológiai felvételezéssel jellemeztük. A cönológiai felvételekben előforduló 27 faj egy-egy példányából hamvasztásos módszerrel nyertük ki a biogén szilíciumot. Minden egyes faj fitolitkészletét több száz fénymikroszkópi fotóval dokumentáltuk. A kétszikűekben 19 fitolit morfotípust különböztettünk meg, szemben a pázsitfüvek 25 fitolit formájával. Ebből 9 morfotípus csak a vizsgált kétszikű fajokban fordult elő, míg a pázsitfüvekben 16 olyan morfotípust találtunk, amely a vizsgált kétszikű fajokra nem jellemző. Várható módon a vizsgált pázsitfüvek fitolit produkciója volt kiemelkedő. A löszvegetáció leíró fitolitvizsgálata mellett vizsgáltuk a növényi fajdiverzitás, és a növényekben tárolódó fitolit morfotípus-diverzitás összefüggéseit. Vizsgálataink alapján összefüggés mutatható ki a halom vegetációjának fajdiverzitása, illetve annak fitolitdiverzitása között. A pázsitfűfajok dominanciája jelentkezik a vegetációra jellemző fitolitkészlet diverzitásban. Eredményeink megalapozzák a fitolit morfotípus-diverzitás, mint paleoökológiai eszköz vegetáció rekonstrukcióban, illetve környezet- és tájtörténeti vizsgálatokban történő alkalmazását is

Zöngedöző

Im Exkurs werden einige Überlegungen angeführt, warum die Gattung »Gemeindelied des 16.-17. Jahrhunderts« in der Geschichte der ungarischen Literatur ihren Platz haben sollte. Im literaturgeschichtlichen Beitrag sind Bemerkungen zu fünf Liedern (2.1-5) von Balázs Lövei zu finden. Balázs . Lövei war evangelisch-lutherischer Pfarrer in Győr und bewegte sich in einem geistigen Kreis in Transdanubien, wo die wichtigste Bekenntnis- und Frömmigkeitsliteratur übersetzt wurde. Lövei soil der Herausgeber des Gesangbuchs Zöngedöző mennyei kar (»Singende himmlische Schar«, zwischen 1692 und 1696) gewesen sein. In diesem Gesangbuch werden evangelisch-lutherische Lieder gesammelt, die in den protestantischen Gesangbüchern nach 1635 fehlten. Im 18. Jahrhundert entfaltete sich eine neue Kirchenlieddichtung innerhalb der lutherischen Kirche, die im wesentlichen durch die Sammlung Zöngedöző mennyei kar angeregt worden war. Im musikalischenAbschnitt werden deutsche Choralmelodien (1-7) analysiert. Der Grof3teil dieser Choralmelodien ist zur Basis kirchenmusikalischer Werke (Choralbearbeitungen, Orgelwerke) geworden. Diese Melodien finden sich nun auch in Zöngedöző mennyei kar. Aus diesem Grunde helfen zahlreiche Chor- und Orgelwerke deutscher Komponisten vergangener Jahrhunderte auch dem heutigen ungarischen Gottesdienstbesucher die Kirchenmusik im Rahmen einer alten Tradition zu verstehen, in der Theologie, Sprache und Musik in einem engen Zusammenhang stehen

Zöngedöző

Im Exkurs werden einige Überlegungen angeführt, warum die Gattung »Gemeindelied des 16.-17. Jahrhunderts« in der Geschichte der ungarischen Literatur ihren Platz haben sollte. Im literaturgeschichtlichen Beitrag sind Bemerkungen zu fünf Liedern (2.1-5) von Balázs Lövei zu finden. Balázs . Lövei war evangelisch-lutherischer Pfarrer in Győr und bewegte sich in einem geistigen Kreis in Transdanubien, wo die wichtigste Bekenntnis- und Frömmigkeitsliteratur übersetzt wurde. Lövei soil der Herausgeber des Gesangbuchs Zöngedöző mennyei kar (»Singende himmlische Schar«, zwischen 1692 und 1696) gewesen sein. In diesem Gesangbuch werden evangelisch-lutherische Lieder gesammelt, die in den protestantischen Gesangbüchern nach 1635 fehlten. Im 18. Jahrhundert entfaltete sich eine neue Kirchenlieddichtung innerhalb der lutherischen Kirche, die im wesentlichen durch die Sammlung Zöngedöző mennyei kar angeregt worden war. Im musikalischenAbschnitt werden deutsche Choralmelodien (1-7) analysiert. Der Grof3teil dieser Choralmelodien ist zur Basis kirchenmusikalischer Werke (Choralbearbeitungen, Orgelwerke) geworden. Diese Melodien finden sich nun auch in Zöngedöző mennyei kar. Aus diesem Grunde helfen zahlreiche Chor- und Orgelwerke deutscher Komponisten vergangener Jahrhunderte auch dem heutigen ungarischen Gottesdienstbesucher die Kirchenmusik im Rahmen einer alten Tradition zu verstehen, in der Theologie, Sprache und Musik in einem engen Zusammenhang stehen

Sleep has no critical role in implicit motor sequence learning in young and old adults

The influence of sleep on motor skill consolidation has been a research topic of increasing interest. In this study we distinguished general skill learning from sequence-specific learning in a probabilistic implicit sequence learning task (Alternating Serial Reaction Time) in young and old adults before and after a 12-hour offline interval which did or did not contain sleep (pm-am and am-pm groups respectively). The results showed that general skill learning, as assessed via overall RT, improved offline in both the young and older groups, with the young group improving more than the old. However, the improvement was not sleep-dependent, in that there was no difference between the am-pm and pm-am groups. We did not find sequence-specific offline improvement in either age group for either the am-pm or pm-am groups, suggesting that consolidation of this kind of implicit motor sequence learning may not be influenced by sleep

The detection and modeling of direct effects in latent class analysis

Several approaches have been proposed for latent class modeling with external variables, including one-step, two-step and three-step estimators. However, very little is known yet about the performance of these approaches when direct effects of the external variable to the indicators of latent class membership are present. In the current article, we compare those approaches and investigate the consequences of not modeling these direct effects when present, as well as the power of residual and fir statistics to identify such effects. The results of the simulations show that not modeling direct effect can lead to severe parameter bias, especially with a weak measurement model. Both residual and fit statistics can be used to identify such effects, as long as the number and strength of these effects is low and the measurement model is sufficiently strong

GABAB receptor-mediated activation of astrocytes by gamma-hydroxybutyric acid

The gamma-aminobutyric acid (GABA) metabolite gamma-hydroxybutyric acid (GHB) shows a variety of behavioural effects when administered to animals and humans, including reward/addiction properties and absence seizures. At the cellular level, these actions of GHB are mediated by activation of neuronal GABAB receptors (GABABRs) where it acts as a weak agonist. Because astrocytes respond to endogenous and exogenously applied GABA by activation of both GABAA and GABABRs, here we investigated the action of GHB on astrocytes on the ventral tegmental area (VTA) and the ventrobasal (VB) thalamic nucleus, two brain areas involved in the reward and proepileptic action of GHB, respectively, and compared it with that of the potent GABABR agonist baclofen. We found that GHB and baclofen elicited dose-dependent (ED50: 1.6 mM and 1.3 µM, respectively) transient increases in intracellular Ca2+ in VTA and VB astrocytes of young mice and rats, which were accounted for by activation of their GABABRs and mediated by Ca2+ release from intracellular store release. In contrast, prolonged GHB and baclofen exposure caused a reduction in spontaneous astrocyte activity and glutamate release from VTA astrocytes. These findings have key (patho)physiological implications for our understanding of the addictive and proepileptic actions of GHB

Anti-inflammatory effects of cell-based therapy with tyrosine hydroxylase-positive catecholaminergic cells in experimental arthritis

Objectives: Studies in rheumatoid arthritis (RA), osteoarthritis (OA) and mice with arthritis demonstrated tyrosine hydroxylase-positive (TH+) cells in arthritic synovium and parallel loss of sympathetic nerve fibres. The exact function of TH+ cells and mode of TH induction are not known. Methods: Synovial cells of RA/OA were isolated and cultured under normoxic/hypoxic conditions with/without stimulating enzyme cofactors of TH and inhibitors of TH. We studied TH expression and release of cytokines/catecholamines. In vivo function was tested by cell therapy with TH+ neuronal precursor cells (TH+ neuronal cells) in DBA/1 mice with collagen type II-induced arthritis (CIA). Results: Compared with normoxic conditions, hypoxia increased TH protein expression and catecholamine synthesis and decreased release of tumour necrosis factor (TNF) in OA/RA synovial cells. This inhibitory effect on TNF was reversed by TH inhibition with α-methyl-para-tyrosine (αMPT), which was particularly evident under hypoxic conditions. Incubation with specific TH cofactors (tetrahydrobiopterin and Fe2+) increased hypoxia-induced inhibition of TNF, which was also reversed by αMPT. To address a possible clinical role of TH+ cells, murine TH+ neuronal cells were generated from mesenchymal stem cells. TH+ neuronal cells exhibited a typical catecholaminergic phenotype. Adoptive transfer of TH+ neuronal cells markedly reduced CIA in mice, and 6-hydroxydopamine, which depletes TH+ cells, reversed this effect. Conclusions: The anti-inflammatory effect of TH+ neuronal cells on experimental arthritis has been presented for the first time. In RA/OA, TH+ synovial cells have TH-dependent anti-inflammatory capacities, which are augmented under hypoxia. Using generated TH+ neuronal cells might open new avenues for cell-based therapy

Effects of dimethyl fumarate on neuroprotection and immunomodulation

BACKGROUND: Neuronal degeneration in multiple sclerosis has been linked to oxidative stress. Dimethyl fumarate is a promising novel oral therapeutic option shown to reduce disease activity and progression in patients with relapsing-remitting multiple sclerosis. These effects are presumed to originate from a combination of immunomodulatory and neuroprotective mechanisms. We aimed to clarify whether neuroprotective concentrations of dimethyl fumarate have immunomodulatory effects. FINDINGS: We determined time- and concentration-dependent effects of dimethyl fumarate and its metabolite monomethyl fumarate on viability in a model of endogenous neuronal oxidative stress and clarified the mechanism of action by quantitating cellular glutathione content and recycling, nuclear translocation of transcription factors, and the expression of antioxidant genes. We compared this with changes in the cytokine profiles released by stimulated splenocytes measured by ELISPOT technology and analyzed the interactions between neuronal and immune cells and neuronal function and viability in cell death assays and multi-electrode arrays. Our observations show that dimethyl fumarate causes short-lived oxidative stress, which leads to increased levels and nuclear localization of the transcription factor nuclear factor erythroid 2-related factor 2 and a subsequent increase in glutathione synthesis and recycling in neuronal cells. Concentrations that were cytoprotective in neuronal cells had no negative effects on viability of splenocytes but suppressed the production of proinflammatory cytokines in cultures from C57BL/6 and SJL mice and had no effects on neuronal activity in multi-electrode arrays. CONCLUSIONS: These results suggest that immunomodulatory concentrations of dimethyl fumarate can reduce oxidative stress without altering neuronal network activity

Gamma-hydroxybutyrate does not maintain self-administration but induces conditioned place preference when injected in the ventral tegmental area

Gamma-hydroxybutyric acid (GHB) is an endogenous brain substance that has diverse neuropharmacological actions, including rewarding properties in different animal species and in humans. As other drugs of abuse, GHB affects the firing of ventral tegmental neurons (VTA) in anaesthetized animals and hyperpolarizes dopaminergic neurons in VTA slices. However, no direct behavioural data on the effects of GHB applied in the VTA or in the target regions of its dopaminergic neurons, e.g. the nucleus accumbens (NAc), are available. Here, we investigated the effects of various doses of intravenous GHB in maintaining self-administration (from 0.001 to 10 mg/kg per infusion), and its ability to induce conditioned place preference (CPP) in rats when given orally (175-350 mg/kg) or injected directly either in the VTA or NAc (from 10 to 300 microg/0.5 microl per side). Our results indicate that while only 0.01 mg/kg per infusion GHB maintained self-administration, although not on every test day, 350 mg/kg GHB given orally induced CPP. CPP was also observed when GHB was injected in the VTA (30-100 microg/0.5 microl per side) but not in the NAc. Together with recent in-vitro findings, these results suggest that the rewarding properties of GHB mainly occur via disinhibition of VTA dopaminergic neurons