Astrocyte-Dependent Slow Inward Currents (SICs) Participate in Neuromodulatory Mechanisms in the Pedunculopontine Nucleus (PPN)

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Ritka betegség, atípusos bőrtünetekkel: felnőttkori Still-betegség = Adult Onset Still’s disease with atypical cutaneous manifestations

A felnőttkori Still-betegség a juvenilis reumatoid artritisz ismeretlen etiológiájú, ritka, felnőttkori variánsa. A szerzők egy 62 éves nőbeteg esetét ismertetik, akit intermittáló magas láz, ízületi fájdalmak, maculo-papulosus bőrtünetek, elesett állapota miatt hoszpitalizáltak. Infekció, reumatológiai betegség, malignus alapbetegség kizárása után, felmerült a felnőttkori Still-betegség lehetősége, melyet az igen magas, izoláltan emelkedett ferritin szint is alátámasztott. A szerzők a cikkben összefoglalják ezzel a komoly diagnosztikus kihívást jelentő betegséggel kapcsolatos új ismereteket is. The adult onset Still’s disease is a rare variant of the systemic juvenile rheumatoid arthritis of unknown origin. This case report is about a 62-year-old woman, who was hospitalized with high recurrent fever, arthralgia and maculopapular rash, in very bad condition. After excluding any infectious, rheumatologic and malignant disease, the possibility of Still’s disease had been confirmed by extreme elevated serum ferritin level. This case report reviews current knowledge about this disease, pointing out it’s diagnostic challenge

Reviving of natural networks in Hungary

In the lecture we explore the habitat restoration works in Hungary in general and we are focusing on the area of Hanság where the latest rehabilitation works enhanced the ecologic value of the area reviving the former richness of marshlands. With the reviving of the former landscape values we are making recommendations for the elaboration of Greenway Natural Jewels of Hanság

The M-current contributes to high threshold membrane potential oscillations in a cell type-specific way in the pedunculopontine nucleus of mice.

The pedunculopontine nucleus is known as a cholinergic nucleus of the reticular activating system, participating in regulation of sleep and wakefulness. Besides cholinergic neurons, it consists of GABAergic and glutamatergic neurons as well. According to classical and recent studies, more subgroups of neurons were defined. Groups based on the neurotransmitter released by a neuron are not homogenous, but can be further subdivided. The PPN neurons do not only provide cholinergic and non-cholinergic inputs to several subcortical brain areas but they are also targets of cholinergic and other different neuromodulatory actions. Although cholinergic neuromodulation has been already investigated in the nucleus, one of its characteristic targets, the M-type potassium current has not been described yet. Using slice electrophysiology, we provide evidence in the present work that cholinergic neurons possess M-current, whereas GABAergic neurons lack it. The M-current contributes to certain functional differences of cholinergic and GABAergic neurons, as spike frequency adaptation, action potential firing frequency or the amplitude difference of medium afterhyperpolarizations (AHPs). Furthermore, we showed that high threshold membrane potential oscillation with high power, around 20 Hz frequency is a functional property of almost all cholinergic cells, whereas GABAergic neurons have only low amplitude oscillations. Blockade of the M-current abolished the oscillatory activity at 20 Hz, and largely diminished it at other frequencies. Taken together, the M-current seems to be characteristic for PPN cholinergic neurons. It provides a possibility for modulating gamma band activity of these cells, thus contributing to neuromodulatory regulation of the reticular activating system

Cholinergic and endocannabinoid neuromodulatory effects overlap on neurons of the pedunculopontine nucleus of mice

The pedunculopontine nucleus (PPN) is a part of the reticular activating system and one of the main sources of the cholinergic fibers in the midbrain, while it is also subject to cholinergic modulation. This nucleus is known to be a structure that controls sleep-wake cycles, arousal, and locomotion. Neurons of the PPN are targets of several neuromodulatory mechanisms, which elicit heterogeneous pharmacological responses including hyperpolarization and depolarization, whereas lack of response can also be observed. In agreement with previous findings, we found that PPN neurons respond to the muscarinic agonist carbachol in a heterogeneous manner: they were depolarized and showed increased firing rate, decreased firing frequency, and were hyperpolarized, or showed no response. The heterogeneity of the muscarinic activation was similar to our previous observations with type 1 cannabinoid (CB1) receptor agonists; therefore, we investigated whether muscarinic and endocannabinoid modulatory mechanisms elicit the same action on a certain neuron. To achieve this, whole-cell patch clamp experiments were conducted on midbrain slices containing the PPN. Carbachol was applied first and, after recording the changes in the membrane potential and the firing frequency and achieving washout, the CB1 receptor agonist arachidonyl-2'-chloroethylamide (ACEA) was applied. A marked but not full overlap was observed: all neurons depolarized by carbachol were depolarized by the CB1 receptor agonist ACEA, and all neurons lacking response to carbachol lacked response to ACEA as well. However, neurons hyperpolarized by carbachol were depolarized, hyperpolarized, or not affected by the ACEA. These results indicate that endocannabinoid and muscarinic modulatory effects involve similar mechanisms of action

A palagáz szerepe a globális földgázkészletek kiaknázásában és az energiaellátásban 2040-ig

Az utóbbi években kiemelt figyelem kíséri a szénhidrogének nem hagyományos úton történő kitermelését és az ehhez kapcsolódó technológia fejlődését. 2040-ig a világon a földgáz lesz az első számú (fosszilis) energiahordozó, a földgáz készleteken belül a palagáz szerepe felértékelődhet. A kitermelési potenciál szempontjából a repesztéses technológia költségei (tőkeigénye) és az ehhez kapcsolódó környezetszennyezés meghatározó tényezők (célzott kutatás-fejlesztéssel próbálják ezeket mérsékelni), ezért a palagáz kitermelésének gyenge a társadalmi elfogadottsága (főként Európában). Globális szinten az USA és a legnagyobb lelőhellyel rendelkező országok pozíciója fogja meghatározni a piacot; az EU várhatóan továbbra is nettó importőr maradhat földgáz tekintetében, azonban az Oroszország-függőség e tekintetben csökkenhet. A potenciális földgáz-palagáz átrendeződés érzékenyen érintheti a jelenleg legnagyobb klasszikus földgázexportőr országok gazdaságát, a politikai stabilitását is, mely komoly következménye lehet a palagázkitermelés lehetséges növekedésének. Kérdés azonban, hogy a környezeti szempontok felülkerekednek-e a politikai kérdéseken, hogy a palagáz kitermelés valóban megoldható-e emberi egészség veszélyeztetése nélkül