Clinical Neuroscience

[Effective, safe stroke prevention with novel oral anticoagulants in patients with atrial fibrillation. Focus on dabigatran]

SZAPÁRY László, FEHÉR Gergely, BOSNYÁK Edit, DELI Gabriella, CSÉCSEI Péter

MAY 30, 2013

Clinical Neuroscience - 2013;66(05-06)

[Non-valvular AF is the most common cardiac arrhytmia. Its incidence increases with age. AF is an independent risk factor for ischaemic stroke, representing a five times higher risk for it, associated with a high mortality rate. Beside AF, there are several other risk factors which influence the risk of stroke. Stroke risk calculator can be used to assess the risk of patient having a stroke. The most endangered group of patients with AF are those who have already suffered from cerebrovascular event. The only effective medication for prevention of stroke due to AF had been the application of vitamin K antagonists (VKA) which considerably decrease the rate of ischaemic event in a patient with AF providing that the INR is in the therapeutic range. VKA have several limitations of use in clinical practice and the fear of bleeding complications results an underusing of these drugs. Only 50% of all patients treated with VKA reaches the therapeutic range of INR. The breakthrough of prevention of stroke in recent years is undisputedly the coming out of novel oral anticoagulants (NOACs, thrombin and Xa-factor inhibitors). Recent studies suggest that these novel drugs prove the same efficacy as VKA drugs, furthermore dabigatran in a dose of 2×150 mg or apixaban in 2×5mg was statistically superior to warfarin in the prevention of stroke. NOACs have shown a large reduction in intracranial hemorrhage compared with warfarin. They are given as a fixed dose and do not require persistent monitoring making them much more convenient. NOACs at guidelines of European Society of Cardiology act as a preferable drugs in case of ischaemic stroke with AF. Probably the extended use of NOACs in clinical practice will be the mainstream of stroke prevention in the future.]

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[Diseased brain, diseased nerves, diseased mind 2013;66(05-06)]

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URBÁN Edina, SZÉL István, FÁY Veronika, DÉNES Zoltán, LIPPAI Zoltán, FAZEKAS Gábor

[We have read several publications of great authority on the neurological profession in the last two years in which were expressed assessments of the current situation combined with opinions about neurology and the necessity to reorganize neurological patient care. These articles took up the question of neurorehabilitation too. The authors, who on a daily basis, deal with the rehabilitation of people with disabilities as a consequence of neurological conditions, summarize some important definitions of rehabilitation medicine and the present system of neurological rehabilitation, as it is defined by the rehabilitation profession.]

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[Targeted nanomedicine in diagnostics and therapy of neurological diseases]

FODOR Bertalan, BARKAI László, VALIKOVICS Attila

[The incidence of neurological diseases increases. The up to date diagnostics and therapeutics approaches require the cost-effective and personalized solutions. The nanomedicine now, - and likely more in the future - opens a new horizon in the treatment of neurological diseases. The nano-size materials have several advantages that make it their use as drug delivery systems, and imaging agent. Very important aspect is that these materials can transfer across the bloodbrain barrier. The functionalization and surface modification of nanomaterials enhances this effect. The authors summarize of neurological application of nanoparticles according to the current data. They provide an overview about the most common used nanomedical materials, targeted drug delivery mechanisms and nano-imaging opportunities.]

Clinical Neuroscience

[Spectral, phase-synchronization, and graph theoretical EEG changes related to mental arithmetics]

BOHA Roland, TÓTH Brigitta, GAÁL Zsófia Anna, KARDOS Zsófia, FILE Bálint, MOLNÁR Márk

[During mental arithmetic operations working memory playsan important role, but there are only few studies in which anattempt was made to separate this effect from the process ofarithmetics per se. In this study the effects of arithmetic onthe EEG of young adults (14 participants, six of themwomen, mean age 21.57 years, SD: 2.62) was investigatedduring a subtraction task in the θ(4-8 Hz) frequency band.Besides the power density spectrum analysis phasesynchrony based on recently developed graph theoreticalmethods were used and strength of local connections (clustercoefficient; C) and global interconnectedness of network(characteristic path length; L) were determined. Before thearithmetic task passive viewing (control situation) and anumber recognition paradigms were used. During the arith-metic task compared to the control situation significantlyincreasing phase synchrony and C values were found. L wassignificantly shorter (F(2, 26)=818.77, p<0.0001) only dur-ing the arithmetic task: this fact and the former two resultsimply that the network topology shifted towards the “smallworld” direction. Our findings concerning regionaldifferences confirm those reported earlier in the literature:compared to the control condition significant task-relatedincrease was found in C values in the parietal areas [moreexplicitly in the left side, (F(1, 13)=7.2020, p=0.0188)],which probably corresponds to stronger local connectionsand more synchronized (sub)networks. During the task con-dition significantly increased θband power; (F(1,13)=7.9708, p=0.0144) and decreased L values werefound in the left frontal region compared to the right side(F(1, 13)=6.0734, p=0.0284), which can also be interpret-ed as an indicator of optimized network topology ofinformation processing.]

Clinical Neuroscience

[Possibilities of gene therapy with recombinant adenovirus in the cortex and hippocampus]

KOSKA Péter, VALIKOVICS Attila, KISS-TÓTH Éva, SZALAI Adrienn, NAGY Zoltán, FODOR Bertalan

[Background and purpose - Neurodegenerative diseases eg. ischemic stroke causes lifelong disabilities in cognitive functions and movement, furthermore high frequency of death. Antiapoptotic, or growth factor gene targeting to cortical structures could be a useful tool for neuroprotection in ischemic brain diseases. In present study we examined the feasibility of the gene therapy of the cortex and hippocampus via transfecting brain with recombinant adenovirus containing LacZ reporter gene in normal and postischemic condition. Since translation of proteins can be inhibited following ischemia by the phosphorylation of ribosomal subunit eIF2α, phosphor-eIF2α immunohystochemistry were performed. Methods - Our adenovirus vector was introduced via the cisterna magna into control and postischemic gerbil brain. After 48 hours of transfection the brains were examined for X-gal staining. LacZ expressing cells showed blue colour. Five min. transient global ischemia was induced by clipping the vertebral and carotid arteries of gerbil. Phosphor-eIF2α immunohystochemistry were performed following 48 hours of ischemia. Results - Administration of adenoviral vector resulted in transfection of hippocampal CA1, CA2, CA3 cell layers while gyrus dentatus remained untransfected. Cortical pyramidal cell layers were also transfected. In postischemic brain the lack of LacZ gene expression were detected in the CA1 and CA2 layer of hippocampus. Ischemia caused eIF2α phosphorylation in hippocampal CA1, CA2, CA3 and most neuronal layers in the cortex. Conclusion - Introducing adenovirus vector via the cisterna magna may results in effective gene therapy of cortex and hippocampus. To develop effective gene therapy in postischemic hippocampal CA1 and CA2 cell layers needs further investigation. eIF2α phosphorylation probably doesn’t interfere with transgene expression.]

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Clinical Neuroscience

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