[ANTISEIZURE ACTIVITY OF C EPHALARIA GIGANTEA ROOT EXTRACT].

Antiseizure activity of Cephalaria gigantea root extract was studied using PTZ- and/or audiogenic seizure models in outbred Wistar and inbred Krouchinsky- Molodkina rats respectively. In PTZ - model onset of tonic- clonic seizures, latencies to the beginning of the seizure activity, and mortality, and similarly in audiogenic seizures behavioral convulsive reactions , facial automatisms and latency to wild running were evaluated. The extract is used traditionally in Georgian folk medicine as anticonvulsant drug. In this study it was evidenced experimentally that extract demonstrates anticonvulsant properties as in both model, as in both routs of administration - peroral and intraperitoneal. Extract appeared most effective in case of preliminary repetitive administration: in PTZ model seizures were eliminated in 9 of 10 animals, and in audiogenic model convulsive response was no more observable during 7 days of treatment termination. It was found also that sedative properties are characteristic of this antiseizure extract according to the sleeping prolongation in barbiturate treated mice. Safety of the extract was evaluated in toxicological acute and chronic experiments, and consequently it is considered a substance of moderate general toxicity.

Preliminary phytochemical and biological evaluation of daphne glomerata extracts.

The article reports on the phytochemical and biological potentials of leaves and stems of Daphne glomerata Lam. (Fam. Thymelaeaceae). Study indicated that crude extracts from the leaves and stems of the plant have high biological activity. Cytotoxicity was assessed using resazurin on an automated 96-well Fluoroskan Ascent F1_ plate reader (Labsystems) using excitation and emission wavelengths of 530 nm and 590 nm, respectively. High cytotoxic activity (<1,563 µg/ml) of both extracts toward lung carcinoma cell lines was elucidated. The specificity of extracts to WS-1 human fibroblast cell lines was observed. For the first time, the profiles of compounds with terpenic and phenolic nature were described in Daphne glomerata leaves and stems MeOH extracts by TLC and (HPLC-DAD-MS) techniques.

Selective presynaptic terminal remodeling induced by spatial, but not cued, learning: a quantitative confocal study.

The hippocampal mossy fibers (MFs) are capable of behaviorally selective, use-dependent structural remodeling. Indeed, we previously observed a new layer of Timm's staining induced in the stratum oriens (SO) in CA3 after spatial but not cued water maze learning (Rekart et al., (2007) Learn Mem 14:416-421). This led to the prediction that there is a learning-specific induction of presynaptic terminal plasticity of MF axons. This study confirms this prediction demonstrating, at the confocal level of analysis, terminal-specific, and behavior-selective presynaptic structural plasticity linked to long-term memory. Male adult Wistar rats were trained for 5 days to locate a hidden or visible platform in a water maze and a retention test was performed 7 days later. MF terminal subtypes, specifically identified by an antibody to zinc transporter 3 (ZnT3), were counted from confocal z-stacks in the stratum lucidum (SL) and the SO. In hidden platform trained rats, there was a significant increase in the number of large MF terminals (LMTs, 2.5-10 µm diameter, >2 µm(2) area) compared to controls both in the proximal SL (P < 0.05) and in the SO (P < 0.01). Surprisingly, there was no detectable increase in small MF terminals (SMTs, 0.5-2 µm diameter, <2 µm(2) area) in either SL or SO as a consequence of training. This distinction of the two MF terminal types is functionally important as LMTs synapse on CA3 pyramidal neurons, while SMTs are known to target inhibitory interneurons. The present findings highlight the pivotal role in memory of presynaptic structural plasticity. Because the "sprouting" observed is specific to the LMT, with no detectable change in the number of the SMT, learning may enhance net excitatory input to CA3 pyramidal neurons. Given the sparse coding of the MF-CA3 connection, and the role that granule cells play in pattern separation, the remodeling observed here may be expected to have a major impact on the long-term integration of spatial context into memory.

[Chromosome instability in patients with different forms of cardiomyopathy and their relatives].

Comparative studies on spontaneous and induced by two agents (mytomycin C and Nickel chloride) chromosome instability have been conducted in cultured lymphocytes derived from patients with hypertrophic and dilated forms of cardiomyopathy (HCMP and DCMP) and their relatives compiling a high-risk group to develop mentioned pathologies. In patients with HCMP and DCMP, as well as in their relatives higher levels of spontaneous chromosome instability were found in comparison with the control group (comprising healthy individuals without cardiomyopathic anamnesis). Almost all the affected patients and their relatives revealed tendency to increased aneuploidy and significant elevation of polyploidy when compared with control values. It was demonstrated that nickel chloride-induced chromosome disorders registered more frequently in lymphocytes of the patients and their relatives than in cells of control subjects, but mytomycin C did not have such an affect. We assume to explain the similarity of studied parameters in patients with cardiomyopathy and their relatives as a consequence of identical rearrangements in genome functioning. The revealed analogy should be interpreted as a pre-illness condition for the individuals included in the risk-group.