Szomatosztatin receptor funkcionális morfológiai vizsgálata a központi idegrendszerben = Functional morphological study of somatostin receptors in the central nervous system

A szomatosztatin 2-es típusú receptor (sst2) in vivo agonista-indukált internalizációja lehetővé tette a receptort expresszáló sejtek azonosítását a patkány parietális agykérgében. Az sst2 receptor a kéreg V. rétegében pyramissejteken, a VI. rétegben kisméretű multipoláris, feltételezhetően glutamaterg neuronokon helyezkedik el. Az sst2 receptor a gyrus dentatusban és a hypothalamus paraventricularis és arcuatus magjaiban perikaryonok és dendritek sejtmembránján helyezkedik el, extraszinaptikusan, egyenletes eloszlásban. A receptor periszinaptikus vagy/és szinaptikus elhelyezkedését vizsgálataink nem támasztották alá. Agonista hatására a hippocampus pyramis- és szemcsesejtjeinek dendritjein elhelyezkedő sst2 receptorok retrográd úton, mikrotubulus-dependens transzporttal a sejttestbe vándorolnak, ott a transz-Golgi hálózatban és a közelében elhelyezkedő vezikulákban tárolódnak, majd visszakerülnek a dendritek membránjára. Hippocampus sclerosissal járó temporális lebeny epilepsziában a gyrus dentatus molekuláris rétegének külső részében, a szomatosztatinerg idegrostok hipertrófiájának megfelelően a szomatosztatin sst2 receptorának helyi down-regulációja következik be. A down-regulácio feltehetően a krónikusan megnövekedett szomatosztatin felszabadulás következménye. | Unraveling the distribution of somatostatin sst2 receptor in the rat parietal cortex was achieved through in vivo agonist-induced internalization of the receptor. Sst2 receptor-expressing cells are pyramidal cells in layer V and small multipolar, presumably glutamatergic neurons in layer VI. In the dentate gyrus and the hypothalamic paraventricular and arcuate nuclei, the sst2 receptor is localized at the plasma membrane of perikarya and dendrites. The sst2 receptor evenly distributed on the entire membrane surface, specific targeting of the receptor to perisynaptic and/or synaptic sites was not revealed. Upon agonist stimulation, dendritic receptors of hippocampal pyramidal and granule cells are retrogradely transported through a microtubule-dependent mechanism to a trans-Golgi network domain, before recycling. In temporal lobe epilepsy with hippocampal sclerosis, in the outer molecular layer of the dentate gyrus, the somatostatin sst2 receptor undergo local down-regulation which corresponded with the sprouting of somatostatinergic fibers. This receptor down-regulation is likely result from chronic somatostatin exposure

The role of currency swaps in the domestic banking system and the functioning the swap market during the crisis

The basic purpose of this study is to didactically demonstrate the factors shaping the currency swap stock of domestic banks prior to the crisis and to provide a descriptive analysis of how the structure and the functioning of the market changed during the crisis. The main conclusions of the study are as follows. In addition to the wide ranging applicability of the transaction, the rise in the currency swap stock of domestic credit institutions is also attributable to macroeconomic factors. The bulk of the exchange rate risk resulting from the high external borrowing requirement and rising external debt was carried by the domestic private sector, while the foreign sector shared a decreasing portion of the risk. The rapid increase in the swap stock was also due to the fact that the synthetic production of foreign currency funds with currency swaps was often more successful than the direct inflow of foreign currency funds. On the basis of the decomposition of the domestic banking system’s on-balance sheet foreign currency position, we can state that it increased mainly as a result of items that also increased the balance sheet total. Following the outbreak of the global financial crisis in the autumn of 2008, the conditions for ensuring foreign currency liquidity deteriorated significantly, which had a substantial effect on implied forint yields, and the turnover and structure of the swap market. While the total average turnover of the domestic FX swap market did not drop radically when the crisis was spreading, market liquidity did decline significantly for a few days and access to foreign currency liquidity became limited. The active role assumed by parent banks and shortening maturities contributed to moderating the decline in turnover. Anecdotal information relating to the tightening of counterparty limits vis-a-vis domestic banks is supported by the decline in the number of non-resident counterparties. The crisis also contributed to changes in the structure of the swap stock. The average remaining maturity of the gross stock began to decline directly after the Lehman bankruptcy, at the time of global dollar liquidity problems, followed by a rise starting from early 2009, principally owing to transactions concluded with parent banks. Domestic subsidiary banks managed to increase maturity primarily through cross-currency swap transactions concluded with intra-group counterparties, but non-group counterparties also concluded transactions with longer maturity with domestic banks.FX swap, currency swap, foreign currency based loan, crisis, counterparty limit, margin call, liquidity requirement

Fuzzy Modeling of Thermoplastic Composites' Melt Volume Rate

Melt volume-flow rate (MVR) is one of the most important quality indicators of composite materials, which depends on the proportion of the component materials. This paper reports the development of a low complexity fuzzy model that describes the relation between percentage amount of multiwall carbon nanotube (MWCNT), acrylonitrile-butadiene-styrene (ABS), polycarbonate (PC) and MVR of the resulting composite. The rule base was generated from a sample data set obtained from experiments by the rule base extension using default set shapes (RBE-DSS) method, and the applied fuzzy inference technique was the least squares method based fuzzy rule interpolation (LESFRI). The resulting model was validated against a separate test data set as well, and it was compared to a fuzzy model generated by a traditional commercial software tool

Ghrelin Decreases Firing Activity of Gonadotropin-Releasing Hormone (GnRH) Neurons in an Estrous Cycle and Endocannabinoid Signaling Dependent Manner.

The orexigenic peptide, ghrelin is known to influence function of GnRH neurons, however, the direct effects of the hormone upon these neurons have not been explored, yet. The present study was undertaken to reveal expression of growth hormone secretagogue receptor (GHS-R) in GnRH neurons and elucidate the mechanisms of ghrelin actions upon them. Ca(2+)-imaging revealed a ghrelin-triggered increase of the Ca(2+)-content in GT1-7 neurons kept in a steroid-free medium, which was abolished by GHS-R-antagonist JMV2959 (10µM) suggesting direct action of ghrelin. Estradiol (1nM) eliminated the ghrelin-evoked rise of Ca(2+)-content, indicating the estradiol dependency of the process. Expression of GHS-R mRNA was then confirmed in GnRH-GFP neurons of transgenic mice by single cell RT-PCR. Firing rate and burst frequency of GnRH-GFP neurons were lower in metestrous than proestrous mice. Ghrelin (40nM-4μM) administration resulted in a decreased firing rate and burst frequency of GnRH neurons in metestrous, but not in proestrous mice. Ghrelin also decreased the firing rate of GnRH neurons in males. The ghrelin-evoked alterations of the firing parameters were prevented by JMV2959, supporting the receptor-specific actions of ghrelin on GnRH neurons. In metestrous mice, ghrelin decreased the frequency of GABAergic mPSCs in GnRH neurons. Effects of ghrelin were abolished by the cannabinoid receptor type-1 (CB1) antagonist AM251 (1µM) and the intracellularly applied DAG-lipase inhibitor THL (10µM), indicating the involvement of retrograde endocannabinoid signaling. These findings demonstrate that ghrelin exerts direct regulatory effects on GnRH neurons via GHS-R, and modulates the firing of GnRH neurons in an ovarian-cycle and endocannabinoid dependent manner

Integrált 4D filmelőkészítő rendszer

Az integrált 4D filmelőkészítő rendszer (i4D-PS) egyedülálló módon nyújt támogatást filmes szakemberek számára a filmgyártás előkészítési fázisában. Rendszerünkkel lehetőség nyílik a teljes forgatókönyv-tervezési folyamat egyszerűbb megvalósítására különböző valós és virtuális helyszínek szintézisén és háromdimenziós megjelenítésén keresztül. Az így elkészült filmvízió mozgókép formájában megtekinthető, és a forgatás szimulációja során kinyert technikai adatok precízen felhasználhatóak a filmgyártásban

A dopamin D4 receptor gén promoter polimorfizmusainak hatása a génexpresszióra in vitro rendszerekben, illetve ezek szerepe a drogfüggőség kialakulásában = Effect of polymorphisms in the dopamine D4 receptor gene promoter on gene expression in vitro and their role in the development of drug addiction

A jelen projekt három részből állt össze. Az első szakaszban folyó molekuláris biológiai munka során a drogfüggőség kialakulásában feltételezhetően szerepet játszó dopamin D4-es receptor (DRD4) gén promoterének polimorfizmusait vizsgáltuk génexpressziós kísérletekkel. Olyan riporter gén-konstruktumokat hozunk létre, melyek a DRD4 gén promoter szakaszának különböző szekvencia-változatait tartalmazták, majd megmértük ezeknek a szekvenciáknak a promoter aktivitását idegi eredetű és kontroll sejteken. A megszokottól eltérő promoter aktivitással rendelkező variánsok funkcionális jelentőségűek lehetnek az opiátfüggőség patogenezisében. A projekt második részében, a pszichológiai vizsgálat során a budapesti Nyírő Gyula kórházban kezelt, és a metadon programban résztvevő opiátfüggők részletes pszichológiai jellemzésére került sor, különös tekintettel a metadonkezelésre adott terápiás válaszukra. A harmadik, genetikai asszociáció-vizsgálatban a DRD4, a szerotonin transzporter (SERT), illetve néhány további, a heroinfüggés kialakulásában, valamint a metadonválszban esetleg szerepet játszó gén polimorfizmusait tanulmányoztuk. A 171 betegtől DNS mintát vettünk, meghatároztuk bennük a különböző genetikai variációkat, majd statisztikai asszociációelemzést végeztünk a metadonválasz, a genetikai markerek és a felvett pszichológiai mérőszámok között. | The current project consists of three parts. In the first phase during the molecular biological work we performed gene expression analyses of the promoter polymorphisms of the dopamine D4 receptor (DRD4) gene, which might play a role in the development of substance dependence. We created gene constructs that included different sequence variants of the DRD4 gene promoter and measured the expressional activity of these constructs in different neural and control cell lines. The variants with an unusual promoter activity might have functional relevance in the pathogenesis of opiate dependence. During the second phase of the project we performed detailed psychological assessment of opiate dependent subjects on methadone maintenance therapy at Nyírő Gyula Hospital in Budapest with special emphasis on their response to methadone. During the third, the genetic association part we studied polymorphisms of genes previously implicated in the development of heroin dependence or involved in methadone response, such as DRD4, the serotonin transporter (SERT), as well as some other genes. We collected DNA samples of 171 patients, determined different genetic variations and performed statistical association analyses regarding methadone response, the genetic markers and the psychological assessment data

Method for Analysis and Prediction of Dwell Times at Stops in Local Bus Transportation

The punctuality of local public bus transportation contributes to the service quality and has impact on mode choice. Appropriate planning and control measures as well as adequate passenger information require efficient analysis and prediction methods. Advanced fleet tracking systems provide enough data for these research purposes. The main factors that cause schedule deviation has been identified through the analysis of the data. As important time elements of the journey time are dwell times at stops, the research focused on it; however, the elaborated database structure is adequate also for analysis of the other time elements, which coincides with our further research intentions too. Innovative methods based on the historical data have been elaborated for the prediction of dwell times. The essence of the method: multi-variate analysis of the dwell times by exploration of the significant influencing factors, and then prediction of times based on the factors describing the certain situations. Soundness of the methods has been verified with examples, and the results well approximated the real values