The present study aimed at exploring a potentially neuroprotective effect of topiramate (TPM), one of the most commonly used newer-generation, broad-spectrum, antiepileptic drugs against ultrastructural damage of hippocampal synaptic endings in the experimental model of febrile seizures (FS). The study used male young Wistar rats aged 22-30 days, divided into three experimental groups and the control group. Brain maturity in such animals corresponds to that of 1-or 2-year-old children. Hyperthermic stress was evoked by placing animals in a 45°C water bath for four consecutive days. TPM at a dose of 80 mg/kg b.m. was administered with an intragastric tube before and immediately after FS. Specimens (1 mm 3) collected from the hippocampal CA1 and CA3 sectors, fixed via transcardial perfusion with a solution of paraformaldehyde and glutaraldehyde, were routinely processed for transmission-electron microscopic analysis. Advanced ultrastructural changes induced by hyperthermic stress were manifested by distinct swelling of hippocampal pre-and post-synaptic axodendritic and axospinal endings, including their vacuolization and disintegration. The axoplasm of the presynaptic boutons contained a markedly decreased number of synaptic vesicles and their abnormal accumulation in the active synaptic region. The synaptic junctions showed a dilated synaptic cleft and a decreased synaptic active zone. TPM used directly after FS was ineffective in the prevention of hyperthermia-induced injury of synaptic endings in hippocampal CA1 and CA3 sectors. However, "prophylactic" administration of TPM, prior to FS induction, demonstrated a neuroprotective effect against synaptic damage in approximately 25% of the synaptic endings in the hippocampal sectors, more frequently located in perivascular zones. It was manifested by smaller oedema of both presynaptic and postsynaptic parts, containing well-preserved mitochondria, increased number and regular distribution of synaptic vesicles within the axoplasm, and increased synaptic active zone. Our current and previous findings suggest that TPM administered "prophylactically", before FS, could exert a favourable effect on some synapses, indirectly, via the vascular factor, i.e. protecting blood-brain barrier components and through better blood supply of the hippocampal CA1 and CA3 sectors, which may have practical implications.

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The commodity market has been becoming one of the main popular segments of the financial markets among individual and institutional investors in recent years, due to downward trend on the stock exchanges. Likely to the equity market, the problem of anomalies in the commodities market is becoming an interesting phenomenon, particularly in the segment of the agricultural market. This paper tests the hypothesis of monthly, the day-of-the week and weekend effects of seven agricultural commodities quoted in the period of 01.01.1994 -31.12.2014. Calculations presented in this paper indicate the absence of the monthly effect on coffee market and the existence of monthly effect in the case of another six analyzed agricultural commodities: corn, wheat, sugar, cocoa, cotton and soybeans. In the analyzed period, no occurrence of day-of-theweek effect was proven for corn, cotton and soybeans. The day-of-the-week effect was registered on the markets of: wheat, coffee, sugar and cocoa and the weekend effect was observed only on the cocoa market.

The commodity market has been becoming one of the most popular segments of the financial markets among individual and institutional investors in recent years. Similarly to the eąuity market, the problem of anomalies in the commodities market is becoming an interesting phenomenon, especially in the segment of the precious metals. This paper tests the hypothesis of monthly, the day-of-the week and weekend effects of the precious metal markets ąuoted on the London Metal Exchange for gold, silver, platinum and copper in the period of 1.01.1995-31.12.2015 considering also palladium in the period 1.01.1998-31.12.2015. Calculations presented in this paper indicate the absence of the monthly effect on gold, silver, platinum, copper markets but proved occurrence of monthly anomaly in the month of September on palladium market. In the analyzed period day- of-the week effect for any of the studied metal markets was not observed but the weekend effect was registered on the gold and copper markets.