Differential recruitment of ventral pallidal e-types by behaviorally salient stimuli during Pavlovian conditioning

The ventral pallidum (VP) is interfacing striatopallidal and limbic circuits, conveying information about salience and valence crucial to adjusting behavior. However, how VP neuron populations with distinct electrophysiological properties (e-types) represent these variables is not fully understood. Therefore, we trained mice on probabilistic Pavlovian conditioning while recording the activity of VP neurons. Many VP neurons responded to punishment (54%), reward (48%), and outcome-predicting auditory stimuli (32%), increasingly differentiating distinct outcome probabilities through learning. We identified e-types based on the presence of bursts or fast rhythmic discharges and found that non-bursting, non-rhythmic neurons were the most sensitive to reward and punishment. Some neurons exhibited distinct responses of their bursts and single spikes, suggesting a multiplexed coding scheme in the VP. Finally, we demonstrate synchronously firing neuron assemblies, particularly responsive to reinforcing stimuli. These results suggest that electrophysiologically defined e-types of the VP differentially participate in transmitting reinforcement signals during learning. © 2021 The Author(s

Változás-detekció és orientáció = Change-detection and orientation

A vizuális eltérési negativitás (vEN) eseményhez kötött potenciál (EKP) összetevő vizsgálatával megállapítottuk, hogy a létezik olyan implicit szenzoros emlékezeti rendszer, mely nem csupán egyedi vizuális sajátságokat tárol, hanem érzékeny sajátság-együttesek (objektumok) változásaira, szekvenciális sajátságokra. Az emlékezeti rendszer 170-200 ms tartományban integrálja a vizuális eseményeket. Az integráció nem magyarázható alacsony szintű szummációs folyamatokkal (mint ahogy a hasonló akusztikus integráció sem). A vizuális ingerlés szabályosságaitól eltérő ingereknek szerepük lehet orientációs folyamatokban, azonban vannak olyan események, melyek önmagukban véve is orientációs hatásokat váltanak ki. Ilyenek lehetnek egyes különöses irritáló hangok, melyek eredményeink szerint már igen kis latenciával kiváltanak olyan EKP összetevőket, melyek eltérnek semleges ingerek hatásaitól. Az orientációra jellemző EKP komponenseket (N2b, P3a), valamint az orientációt kísérő vegatatív válaszokat az életkori változások függvényében elemeztük. Kimutattuk, hogy idős személyeknél ezek a válaszok kisebb intenzitásúak, azonban amennyiben megjelennek, hosszabb ideig maradnak fenn. E jelenséget a gátló működések csökkent hatékonyságával magyarázzuk. Az EKP hatásokhoz hasonló életkori változásokat tapasztaltunk a bőrvezetéses válaszban, a szívritmus változás ugyanakkor nem mutatott hasonló hatásokat. Az orientációs változásokat elemeztük hipoxia esetében. | Investigating the visual mismatch negativity (vMMN) event-related potential (ERP) component, we disclosed a sensory memory system capable of registering feature conjunctions (objects) and sequential regularities. This memory system is working in chunks of 170-200 ms. This temporal integration process is beyond the level of temporal summation. Accordingly, like in the auditory modality, this system is not only a ?change-detection device? sensitive to individual stimulus features. Detecting violations of regularities, processes underlying vMMN (and auditory MMN) may contribute to the initialization of orienting processes. However, certain stimuli elicit orientation-like responses without regulation violation. We demonstrated such early ERP effects to particularly unpleasant noises. We investigated orientation-related ERP effects (N2b, P3a) and autonomous responses in older participants. According to the results these responses are less intensive in elderly. However, habituation processes appeared to slower in the older group. Unlike heart-rate, skin-conductance responses had similar aging-related changes to the ERPs. Orientation-related ERP changes were also investigated in hypoxia

Order of current variance and diffusivity in the rate one totally asymmetric zero range process

We prove that the variance of the current across a characteristic is of order t^{2/3} in a stationary constant rate totally asymmetric zero range process, and that the diffusivity has order t^{1/3}. This is a step towards proving universality of this scaling behavior in the class of one-dimensional interacting systems with one conserved quantity and concave hydrodynamic flux. The proof proceeds via couplings to show the corresponding moment bounds for a second class particle. We build on the methods developed by Balazs-Seppalainen for asymmetric simple exclusion. However, some modifications were needed to handle the larger state space. Our results translate into t^{2/3}-order of variance of the tagged particle on the characteristics of totally asymmetric simple exclusion.Comment: 23 pages; some minor typos correcte

A legismertebb termesztett gombafajok környezetkímélő, korszerű táptalajainak kidolgozása = Preparing up-to-date, environment friendly substrates for the best known cultivated mushroom species

A terméshozamok növelése céljából kétféle hőkezeléssel (nedves, száraz) előállított szalma táptalajon dúsítási kísérletet végeztünk négy gombafajjal (Agaricus bisporus, Agaricus bitorquis, Pleurotus ostreatus, Lentinula edodes). A hőkezelt szalmához borsószalmát, szójaszalmát, lucernalisztet, buzakorpát és ProMycelt kevertünk 1, 2 és 3%-ban. A kísérletet petri-csészében laboratóriumban kezdtük. A legjobb eredményt adó dúsítóanyagggal folytattuk tovább 500, 2000, majd 5000 g-ros kiszerelésű zacskóban, két ismétlésben. A vizsgálatok kiterjedtek a táptalaj N-tartalmának a vizsgálatára, az első szedés idejére, a terméshozamra és az éréslefutásra. A nedvesen hőkezelt dúsított táptalajon az első szedés három fajnál (A. bisporus, A. bitorquis, Lentinula edodes) néhány nappal megelőzte a szárazon hőkezelt táptalajról való szedést. A dúsítóanyagok közül a legmagasabb hozamot a nedvesen hőkezelt ProMycel (3%) dúsítóanyaggal kevert táptalajról kaptuk (A. bisporusnál 3400 g, A. bitorquisnál 2300g L. edodesnél 2600 g/10 kg táptalaj). Néhány százalékkal kisebb hozamot értünk el a szárazon hőkezelt táptalajon. A legkevesebb hozamot a kezeletlen tehát a kontroll szalma adta. A terméshozamot kisebb mértékben lehetett növelni lucernaliszttel és búzakorpával is. Az eerdmények azt mutattak, hogy a hőkezelt szalna N-dúsításának nagy jelentősége van a hozamok növelése szempontjából. A vizsgált dúsítóanyagok mindegyike egyedül a Pleurotus ostreatusnál nem okoztak termésnövekedést. | In order to increase yield quantities 4 mushroom species (Agaricus bisporus, Agaricus bitorquis, Pleurotus ostreatus, Lentinula edoes) were tested for reaction to enrichment on heat-treated (dry and wet) straw substrate. Pea straw, alfalfa meal, wheat bran and ProMycel were mixed into the heat-treated straw in proportion of 1, 2, 3 per cent. Trials started in the laboratory in Petri dishes and were continued with agents of the best results in bags of 500, 2000 and 5000 g in 2 replications. Tests included the N-content of the substrate, the time of the first harvest and the ripening period. In 3 species (A. bisporus, A. bitorquis, Lentinula edodes) the first flush on wet heat-treated and enriched substrate was some days earlier than on dry heat-treated substrate. Of the enrichment agents 3% ProMycel produced the highest yield on wet heat-treated substrate (in A. bisporus 3400 g, in A. birorquis 2300 g, in L. edodes 2600 g/10 kg substrate). Some per cent lower yield was harvested on the dry heat-treated substrate. The untreated straw control gave the lowest yield. In smaller extent yield could also be improved with alfalfa meal and wheat bran

Synthesis and serum protein binding of novel ring-substituted harmine derivatives

A series of new derivatives of the natural β-carboline alkaloid harmine, introducing hydrophobic substituents into positions 7 and 9 were synthetized as potential anticancer agents. Their binding affinities for human serum albumin (HSA) and α1-acid glycoprotein (AAG) were investigated by affinity chromatography combined with fluorescence, circular dichroism (CD) and UV absorption spectroscopy. The weak binding of harmine to both proteins (Ka ~ 3 × 104 M-1) was highly increased by aromatic substitutions (Ka ~ 105-106 M-1). Derivatives having a substituted benzyl group in the N9-position of the β-carboline nucleus showed about tenfold and hundredfold affinity enhancement for HSA and AAG, respectively. Such a strong plasma protein interaction would be of pharmacokinetic relevance for these potential drug candidates. Induced CD spectra indicated the variant selective, dimeric binding of the 7-pyridylethoxy derivative to AAG. Absorbance and fluorescence spectra refer to the binding preference of the neutral form of the studied β-carbolines for both proteins

Influence of acid-induced conformational variability on protein separation in reversed phase high performance liquid chromatography

Influence of acid concentration in the mobile phase on protein separation was studied in a wide concentration range of using trifluoroacetic acid (TFA) and formic acid (FA). At low, 0.001-0.01 v/v% TFA concentration and appropriate solvent strength proteins elute before the column's dead time. This is explained by the proteins having a structured, but relatively extended conformation in the eluent; and are excluded from the pores of the stationary phase. Above ca. 0.01-0.05 v/v% TFA concentration proteins undergo further conformational change, leading to a compact, molten globule-like structure, likely stabilized by ion pairing. Proteins in this conformation enter the pores and are retained on the column. The results suggest a pore exclusion induced separation related to protein conformation. This effect is influenced by the pH and type of acid used, and is likely to involve ion-pair formation. The TFA concentration needed to result in protein folding (and therefore to observe retention on the column) depends on the protein; and therefore can be utilized to improve chromatographic performance. Conformation change was monitored by circular dichroism spectroscopy and mass spectrometry; and it was shown that not only TFA, but FA can also induce molten globule formation