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Background and purpose Acute mortality rate of stroke in Hungary is significantly higher than in Western Europe, which is likely to be partially attributable to suboptimal treatment. Methods We examined the use of acute vascular imaging and mechanical thrombectomy for acute ischaemic stroke patients. We collected data on 20 consecutive patients from Hungarian stroke centers before 31st August 2016. Results Out of the reported 410 patients, 166 (40.4%) underwent CT angiography and 44 (10.7%) had mechanical thrombectomy. Conclusion Only about 1/3 of acute ischaemic stroke patients eligible for thrombectomy actually had it. The underlying reasons include long onset-to-door time, low utilization of acute vessel imaging and a limited neuro-intervention capacity needing improvement.

Summary: Purpose: Valproate (VPA) is an extensively used drug in the therapy of epilepsies. One of the most frequently reported side effects of VPA is hemorrhagic diathesis. Some authors emphasized the decreased platelet count as the basis of VPA-induced hemorrhagic diathesis, but some reports suggested that a significant proportion of patients with normal platelet count may still have an altered platelet function. The mechanism of the VPA-induced platelet dysfunction has not yet been elucidated. A determining element of platelet functions is the arachidonate cascade. Present ex vivo experiments were designed to determine whether a relation exists between the incidence of hemostasis caused by VPA and the effect of this drug on the arachidonate cascade of platelets. Methods: Platelets were isolated from patients receiving long-term VPA treatment (serum level, 36.04 ± 16.12 μg/ml; n = 10) or carbamazepine (CBZ) treatment (serum level, 5.24 ± 2.67 μg/ml; n = 10) and were labeled with [14C]arachidonic acid. (CBZ-treated patients were chosen as a control group, because CBZ causes blood dyscrasias similar to those elicited by VPA, but there has been no report that CBZ induces a platelet dysfunction.) The 14C-eicosanoids were separated by means of overpressure thin-layer chromatography and determined quantitatively by liquid scintillation. Results: Even when the mean plasma concentration of the drug was low, VPA treatment reduced the activity of the arachidonate cascade in platelets. VPA effectively inhibited the cyclooxygenase pathway and the synthesis of the strong platelet aggregator thromboxane A2. Conclusions: Inhibition of the platelet arachidonate cascade may contribute to the platelet-function alterations caused by VPA.

Dystonia is a syndrome characterized by sustained muscle contraction. It is frequently causing twisting and repetitive movements, or leading to development abnormal postures. The management of the disease is usually consists of medication, surgical interventions, botulinum toxin injection, or other complementary methods. The authors have been using the botulinum toxin treatment since 1991.The goal of the study was to investigate the efficacy and safety of the botulinum toxin injection, in patients with focal dystonia and hemifacial spasm.A total of 94 patients diagnosed with cervical dystonia (n=33), blepharospasm (n=32), or hemifacial spasm (n=29) were treated. The mean age of the patients was 62.4 years, and the mean duration of the therapy was 6.8 years. The medication took place with local injection of botulinum toxin type A. The efficacy of the treatment was assessed with Patient Global Impression scale. The authors also evaluated the side effects and complications of the therapy, as well as the causes of the treatment discontinuation.The botulinum toxin treatment was effective in 92% of the patients. It is a great importance that the therapy resulted significantly improvement in 56% of the patients. There was no significant difference neither among the types of the dystonia (cervical dystonia 87%, blepharospasm 93%, and hemifacial spasm 96%), nor among the medications (Botox 92%, Dysport 92%) in point of efficacy. Temporary weakness occurred only at 6 patients. There was neither serious side effect, nor complication related to the treatment.The authors can conclude that the botulinum toxin injection is effective and safe therapy, in the patients with cervical dystonia, blepharospasm, and hemifacial spasm.

Summary: Purpose: The functional significance of gap-junction (GJ) channels in seizure susceptibility and induction and maintenance of seizures in the developing rat brain was investigated on the 4-aminopyridine (4-AP) in vivo epilepsy model. Methods: In electrophysiological experiments, GJs were manipulated with a blocker or opener before induction or at the active epileptic foci between postnatal days 9 and 28 (P9–28). Semiquantitative reverse transcriptase–polymerase chain reaction (RT-PCR) amplification was used to measure the levels of connexin (Cx) 26, 32, 36, and 43 mRNAs at the untreated cortex or epileptic foci. Results: The basic electrocorticogram (ECoG) and Cx messenger RNA (mRNA) expression patterns exhibited characteristic maturation; the 4-AP–induced epileptiform activity correlated well with these changes. Cx mRNA expressions were significantly upregulated around P16 (except for Cx26). The Cx26, 36, and 43 gene inducibility was highest around P16 and then declined significantly. In the youngest animals, the GJ opener induced rhythmic synchronous cortical activity. On maturation, the seizures became focalized and periodic; the discharges accelerated their amplitude and frequency increase. A transient decrease (P13–14) and then increase (P15–16) in seizure susceptibility were followed by a tendency to periodicity and focalization. Conclusions: The study suggests that GJ communication is involved in rhythm genesis and synchronization of cortical activity and may enhance the epileptogenicity of the developing brain.

In the present electrophysiological study the effect of aminooxyacetic acid (AOAA) on the cortical epileptogenicity, and on the basic electro-cortical activity was investigated in anesthetized rats. AOAA did not induce spontaneous epileptiform discharges but modified the somato-sensory evoked responses and the cortical epileptogenicity (induced by 4-aminopyridine) in the same manner depending on its concentration. AOAA at low concentrations increased the amplitude of evoked responses and the ipsilateral manifestation of epileptiform activity, however, at high concentrations significantly suppressed both the evoked responses and the induction and expression of seizures discharges. The anticonvulsive effect of AOAA was time-dependent (reached its maximum after 2h AOAA pre-treatment) and reversible. AOAA at low concentrations probably increases the efficacy of the NMDA excitatory system and decreases GABA-synthesis, resulting neuronal hyperexcitation. However, AOAA at high concentrations can lead to an effective cortical inhibition through intra- and extracellular accumulation of GABA. The gradual GABA accumulation - up to a certain level - at the synapses could also explain the time-dependency of the anticonvulsive effect of AOAA.

Long-term administration of the antiepileptic drug valproate can induce hematologic, hepatic and endocrine abnormalities and morphologic alterations in the brain capillaries and glial cells. Valproate elicits bone marrow suppression, reducing the number of red blood cells and platelets, and causes platelet functional abnormalities. Various data suggest that more than one mechanism of valproate-associated toxicity may exist, but the pathomechanism of cell function alterations elicited by valproate has not yet been elucidated. The reported ex vivo experiments were designed to investigate the effects of valproate on the arachidonic acid cascade of rat brain capillaries and platelets. Valproate was administered (300 mg/kg body weight/day) in the drinking water to male Wistar rats for 2 weeks. isolated platelets and brain microvessels were labelled with [C-14]arachidonic acid and the released [C-14]eicosanoids were separated by overpressure thin-layer chromatography and determined quantitatively by liquid scintillation counting. Valproate treatment reduced the synthesis of cyclooxygenase and lipoxygenase products in rat platelets, in brain microvessels valproate stimulated the synthesis of Lipoxygenase metabolites and attenuated the cyclooxygenase pathway. Modifications of the arachidonate cascade in platelets and brain microvessels may contribute to the cell function alterations caused by valproate. (C) 2000 Elsevier Science B.V. All rights reserved.