Clinical Neuroscience

[Diseased brain, diseased nerves, diseased mind]


MAY 30, 2013

Clinical Neuroscience - 2013;66(05-06)

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



Further articles in this publication

Clinical Neuroscience

[Neurorehabilitation, neurology, rehabilitation medicine]

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.]

Clinical Neuroscience

[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

[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

[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.]

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.]

All articles in the issue

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Clinical Neuroscience

Late simultaneous carcinomatous meningitis, temporal bone infiltrating macro-metastasis and disseminated multi-organ micro-metastases presenting with mono-symptomatic vertigo – a clinico-pathological case reporT

JARABIN András János, KLIVÉNYI Péter, TISZLAVICZ László, MOLNÁR Anna Fiona, GION Katalin, FÖLDESI Imre, KISS Geza Jozsef, ROVÓ László, BELLA Zsolt

Although vertigo is one of the most common complaints, intracranial malignant tumors rarely cause sudden asymmetry between the tone of the vestibular peripheries masquerading as a peripheral-like disorder. Here we report a case of simultaneous temporal bone infiltrating macro-metastasis and disseminated multi-organ micro-metastases presenting as acute unilateral vestibular syndrome, due to the reawakening of a primary gastric signet ring cell carcinoma. Purpose – Our objective was to identify those pathophysiological steps that may explain the complex process of tumor reawakening, dissemination. The possible causes of vestibular asymmetry were also traced. A 56-year-old male patient’s interdisciplinary medical data had been retrospectively analyzed. Original clinical and pathological results have been collected and thoroughly reevaluated, then new histological staining and immunohistochemistry methods have been added to the diagnostic pool. During the autopsy the cerebrum and cerebellum was edematous. The apex of the left petrous bone was infiltrated and destructed by a tumor mass of 2x2 cm in size. Histological reexamination of the original gastric resection specimen slides revealed focal submucosal tumorous infiltration with a vascular invasion. By immunohistochemistry mainly single infiltrating tumor cells were observed with Cytokeratin 7 and Vimentin positivity and partial loss of E-cadherin staining. The subsequent histological examination of necropsy tissue specimens confirmed the disseminated, multi-organ microscopic tumorous invasion. Discussion – It has been recently reported that the expression of Vimentin and the loss of E-cadherin is significantly associated with advanced stage, lymph node metastasis, vascular and neural invasion and undifferentiated type with p<0.05 significance. As our patient was middle aged and had no immune-deficiency, the promoting factor of the reawakening of the primary GC malignant disease after a 9-year-long period of dormancy remained undiscovered. The organ-specific tropism explained by the “seed and soil” theory was unexpected, due to rare occurrence of gastric cancer to metastasize in the meninges given that only a minority of these cells would be capable of crossing the blood brain barrier. Patients with past malignancies and new onset of neurological symptoms should alert the physician to central nervous system involvement, and the appropriate, targeted diagnostic and therapeutic work-up should be established immediately. Targeted staining with specific antibodies is recommended. Recent studies on cell lines indicate that metformin strongly inhibits epithelial-mesenchymal transition of gastric cancer cells. Therefore, further studies need to be performed on cases positive for epithelial-mesenchymal transition.

Clinical Neuroscience

Atypical presentation of late-onset Sandhoff disease: a case report

SALAMON András , SZPISJAK László , ZÁDORI Dénes, LÉNÁRT István, MARÓTI Zoltán, KALMÁR Tibor , BRIERLEY M. H. Charlotte, DEEGAN B. Patrick , KLIVÉNYI Péter

Sandhoff disease is a rare type of hereditary (autosomal recessive) GM2-gangliosidosis, which is caused by mutation of the HEXB gene. Disruption of the β subunit of the hexosaminidase (Hex) enzyme affects the function of both the Hex-A and Hex-B isoforms. The severity and the age of onset of the disease (infantile or classic; juvenile; adult) depends on the residual activity of the enzyme. The late-onset form is characterized by diverse symptomatology, comprising motor neuron disease, ataxia, tremor, dystonia, psychiatric symptoms and neuropathy. A 36-year-old female patient has been presenting progressive, symmetrical lower limb weakness for 9 years. Detailed neurological examination revealed mild symmetrical weakness in the hip flexors without the involvement of other muscle groups. The patellar reflex was decreased on both sides. Laboratory tests showed no relevant alteration and routine electroencephalography and brain MRI were normal. Nerve conduction studies and electromyography revealed alterations corresponding to sensory neuropathy. Muscle biopsy demonstrated signs of mild neurogenic lesion. Her younger brother (32-year-old) was observed with similar symptoms. Detailed genetic study detected a known pathogenic missense mutation and a 15,088 base pair long known pathogenic deletion in the HEXB gene (NM_000521.4:c.1417G>A; NM_000521:c.-376-5836_669+1473del; double heterozygous state). Segregation analysis and hexosaminidase enzyme assay of the family further confirmed the diagnosis of late-onset Sandhoff disease. The purpose of this case report is to draw attention to the significance of late-onset Sandhoff disease amongst disorders presenting with proximal predominant symmetric lower limb muscle weakness in adulthood.

Clinical Neuroscience

Neuroscience highlights: The mirror inside our brain

KRABÓTH Zoltán, KÁLMÁN Bernadette

Over the second half of the 19th century, numerous theories arose concerning mechanisms involved in understanding of action, imitative learning, language development and theory of mind. These explorations gained new momentum with the discovery of the so called “mirror neurons”. Rizzolatti’s work inspired large groups of scientists seeking explanation in a new and hitherto unexplored area of how we perceive and understand the actions and intentions of others, how we learn through imitation to help our own survival, and what mechanisms have helped us to develop a unique human trait, language. Numerous studies have addressed these questions over the years, gathering information about mirror neurons themselves, their subtypes, the different brain areas involved in the mirror neuron system, their role in the above mentioned mechanisms, and the varying consequences of their dysfunction in human life. In this short review, we summarize the most important theories and discoveries that argue for the existence of the mirror neuron system, and its essential function in normal human life or some pathological conditions.

Clinical Neuroscience

A variant of Guillain-Barre syndrome after SARS-CoV-2 vaccination: AMSAN

TUTAR Kaya Nurhan, EYIGÜRBÜZ Tuğba, YILDIRIM Zerrin, KALE Nilufer

Introduction - Coronavirus disease 2019 (COVID-19) is a respiratory infection that has rapidly become a global pandemic and vaccines against SARS-CoV-2 have been developed with great success. In this article, we would like to present a patient who developed Guillain-Barré syndrome (GBS), which is a serious complication after receiving the inactive SARS-CoV-2 vaccine (CoronaVac). Case report – A 76-year-old male patient presented to the emergency department with nine days of progressive limb weakness. Two weeks prior to admission, he received the second dose of CoronaVac vaccine. Motor examination revealed decreased extremity strength with 3/5 in the lower extremities versus 4/5 in the upper extremities. Deep tendon reflexes were absent in all four extremities. Nerve conduction studies showed predominantly reduced amplitude in both motor and sensory nerves, consistent with AMSAN (acute motor and sensory axonal neuropathy). Conclusion - Clinicians should be aware of the neuro­logical complications or other side effects associated with COVID-19 vaccination so that early treatment can be an option.

Clinical Neuroscience

Neuroscience highlights: Main cell types underlying memory and spatial navigation

KRABOTH Zoltán, KÁLMÁN Bernadette

Interest in the hippocampal formation and its role in navigation and memory arose in the second part of the 20th century, at least in part due to the curious case of Henry G. Molaison, who underwent brain surgery for intractable epilepsy. The temporal association observed between the removal of his entorhinal cortex along with a significant part of hippocampus and the developing severe memory deficit inspired scientists to focus on these regions. The subsequent discovery of the so-called place cells in the hippocampus launched the description of many other functional cell types and neuronal networks throughout the Papez-circuit that has a key role in memory processes and spatial information coding (speed, head direction, border, grid, object-vector etc). Each of these cell types has its own unique characteristics, and together they form the so-called “Brain GPS”. The aim of this short survey is to highlight for practicing neurologists the types of cells and neuronal networks that represent the anatomical substrates and physiological correlates of pathological entities affecting the limbic system, especially in the temporal lobe. For that purpose, we survey early discoveries along with the most relevant neuroscience observations from the recent literature. By this brief survey, we highlight main cell types in the hippocampal formation, and describe their roles in spatial navigation and memory processes. In recent decades, an array of new and functionally unique neuron types has been recognized in the hippocampal formation, but likely more remain to be discovered. For a better understanding of the heterogeneous presentations of neurological disorders affecting this anatomical region, insights into the constantly evolving neuroscience behind may be helpful. The public health consequences of diseases that affect memory and spatial navigation are high, and grow as the population ages, prompting scientist to focus on further exploring this brain region.