Clinical Neuroscience

[László Vécsei: Kynurenines in the Brain: From Experiments to Clinics]

FAZEKAS András

JULY 30, 2006

Clinical Neuroscience - 2006;59(07-08)

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Clinical Neuroscience

[THE IMPACT OF MOOD ALTERATIONS ON CREATIVITY]

JANKA Zoltán

[Basic elements of artistic (and other) creativity are the technical-professional skill and knowledge, the special talent and ability and the willingness or motivation; one of which being absent results in partially realised creativities like juvenile, frustrated or abandoned types, respectively. Psychometric scales have been developed to measure everyday and eminent creativities, which show that creativity correlates with higher psychoticism, impulsivity and venturesomeness scores and with lower neuroticism and conformity scores of the personality test employed in a general population. Among the psychological components of creativity are the cognitive processes, mood, motivation, and personality traits. Regarding mood, a theory of “inverted U” has been proposed as elevation of mood facilitates creativity to a certain point after what extreme increase has an adverse effect on achievement. Analysing psychopathology and creativity among various professions, higher rates of psychopathology, especially affective symptoms, have been found in art-related professions. Examples of immortal poets, writers, painters, sculptors and composers, having created invaluable cultural treasures for the mankind, illustrate that many of them showed signs of mood alterations (unipolar or bipolar affective disorder spectrum) which were expressed in their artistic products.]

Clinical Neuroscience

[PARALLEL PROCESSING OF VISUAL INFORMATION]

BENEDEK György, JANÁKY Márta, BENEDEK Krisztina, KÉRI Szabolcs

[This is a survey on the function of parallel visual pathway with a special emphasis on its clinical implications. It is based on data in the literature and own results of our group. The paper primarily deals with the X, Y, W pathways and by the magnocellular, parvocellular and koniocellular visual pathways characterized by cells of various size as well as by nerve fibers of various thickness. Electrophysiological, microelectrode recording of single-unit activity makes the distinction between the pathways available in animal modell. Much more difficulties arise if we intend to characterize the pathways in humans or to detect the selective damage of one of these pathways in patients. The non-invasive diagnostic methods that could be used in the diagnosis are detailed here, too. Finally, the neurological, ophtalmological and psychological diseases are discussed in which a selective damage of any visual pathway is suspected. Summing it up, the survey provides evidences for the introduction of the novel concept of parallel pathways into the diagnostic aspects of ophthalmology, neurology and psychiatry.]

Clinical Neuroscience

[Novel forms of eating disorders]

TÚRY Ferenc, LUKÁCS Liza

Clinical Neuroscience

[THE AUGMENTATION OF CLOZAPINE TREATMENT WITH ELECTROCONVULSIVE THERAPY]

GAZDAG Gábor, KOCSIS-FICZERE Nárcisz, TOLNA Judit

[Objectives - The assessment, in terms of safety and efficacy, of augmenting clozapine monotherapy, as well as combined psychopharmacotherapy involving clozapine, with electroconvulsive therapy (ECT). Method - Reviewed were the charts of patients who received clozapine-ECT treatment in the Department of Psychiatry and Psychotherapy of Semmelweis University between November 1999 and December 2003. Results - During the studied period there were altogether 43 patients treated with the combination of clozapine and electroconvulsive therapy. In the schizoaffective group, the values for post-electroconvulsive therapy CGI were significantly lower than either in the catatonic (Z=-3.72, p<0.01) or in the hebephrenic (Z=-3.17, p<0.01) group. Among the groups created on the basis of the number of augmentation strategies utilized, the clozapine+3 group consisted of patients significantly older than the clozapine+1 group (Z=2.45, p=0.01). In the clozapine monotherapy group, the values for post-electroconvulsive therapy CGI were significantly lower than in any of the groups that had received a combination of augmentations (monotherapy-1 augmentation: Z=-3.01, p<0.01; monotherapy-2 augmentation: Z=-2.89, p<0.01; monotherapy- 3 augmentation: Z=-2.41, p=0.01). Conclusions - According to our examinations, the augmentation of clozapine treatment with electroconvulsive therapy should be tried primarily on schizoaffective patients, in case the clozapine monotherapy is ineffective. The simultaneous use of different augmentation strategies is expected to increase only the side effects not the efficacy of the treatment.]

Clinical Neuroscience

[THE ROLE OF MICRO-AROUSALS IN THE REGULATION OF SLEEP]

HALÁSZ Péter

[This work give a short account about a three decades research of the sleep microstructure. The studies, executed by the Strassbourg, Budapest and Parma schools, paved the way of exploring the participation of micro-arousals in the sleep regulation. It was shown that micro-arousals, not leading to instant arousal but influencing the later course of sleep are weaved into the network of sleep. A certain class of microarousals differs from the traditional desyncronisation-type and in a paradox way result a rebound like mobilisation of sleeplike activity with deltas and K-complexes. The desynchronisation- and synchronisation-type micro-arousals show different distribution along the sleep cyclicity and may play different role in sleep regulation. On the basis of the studies dealing with micro-arousals we can assume that beside the traditional long time constant, brain stem driven tonic chemical regulation, an other phasic regulation, with shorter time constant, underlied by the micro-arousals, also exist. This kind of phasic regulation makes sleep flexible and possible to adapt the actual sleep course to the inner and outer demands. An other important role of micro-arousals in pathological sleeps is to provide a gate for the different pathological events, pinpointing the key-points where these events could be expected in the sleep process.]

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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

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

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.

Clinical Neuroscience

Matrix metalloproteinases and their tissue inhibitors in relapsing remitting multiple sclerosis: Possible markers and treatment agents

SANLI Arzu, OZTURK Musa, SOYSAL Aysun, DOVENTAS Yasemin, BASOGLU Fulya, GOZUBATIK-CELIK R. Gokcen, BAYBAS Sevim

Matrix metalloproteinases (MMPs), which are synthesized by many cell groups and responsible for the destruction of matrix proteins, and endogen tissue inhibitors of MMPs (TIMPs) have a role in the pathogenesis of Multiple Sclerosis (MS) by affecting the blood-brain barrier. We aimed to investigate the role of MMPs and TIMPs in the immunopathogenesis and in the course of multiple sclerosis (MS). We enrolled 25 relapsing remitting MS patients, who had a definite MS diagnosis according to McDonald criteria and 25 healthy subjects similar for age and gender as control group. MMP-9- and TIMP-1 levels were measured twice in patient group (one time during an attack and one in remission) and once in healthy subjects. MMP-9- and TIMP-levels of patients during attack and remission period and MMP-9/TIMP-1 ratio were found significantly higher than in the control subjects. In patient group MMP-9 and TIMP-1 levels and MMP-9/TIMP-1 ratio during attacks were not significantly different than during remission period. However, when subdivided according to their number of attacks, patients with 2 attacks had significantly higher levels during attack period comparing to remission period (p<0.05); in case of patients with more than 2 attacks did not have a statistically significant difference in attack and remission periods. Matrix metalloproteinases are important actors in MS immunopathogenesis, particularly in the early period and inhibitor agents for these enzymes can be used as a treatment option.

Clinical Neuroscience

Life threatening rare lymphomas presenting as longitudinally extensive transverse myelitis: a diagnostic challenge

TOLVAJ Balázs, HAHN Katalin, NAGY Zsuzsanna, VADVÁRI Árpád, CSOMOR Judit, GELPI Ellen, ILLÉS Zsolt, GARZULY Ferenc

Background and aims – Description of two cases of rare intravascular large B-cell lymphoma and secondary T-cell lymphoma diagnosed postmortem, that manifested clinically as longitudinally extensive transverse myelitis (LETM). We discuss causes of diagnostic difficulties, deceptive radiological and histological investigations, and outline diagnostic procedures based on our and previously reported cases. Case reports – Our first case, a 48-year-old female was admitted to the neurological department due to paraparesis. MRI suggested LETM, but the treatments were ineffective. She died after four weeks because of pneumonia and untreatable polyserositis. Pathological examination revealed intravascular large B-cell lymphoma (IVL). Our second case, a 61-year-old man presented with headache and paraparesis. MRI showed small bitemporal lesions and lesions suggesting LETM. Diagnostic investigations were unsuccessful, including tests for possible lymphoma (CSF flow cytometry and muscle biopsy for suspected IVL). Chest CT showed focal inflammation in a small area of the lung, and adrenal adenoma. Brain biopsy sample from the affected temporal area suggested T-cell mediated lymphocytic (paraneoplastic or viral) meningoencephalitis and excluded diffuse large B-cell lymphoma. The symptoms worsened, and the patient died in the sixth week of disease. The pathological examination of the presumed adenoma in the adrenal gland, the pancreatic tail and the lung lesions revealed peripheral T-cell lymphoma, as did the brain and spinal cord lesions. Even at histological examination, the T-cell lymphoma had the misleading appearance of inflammatory condition as did the MRI. Conclusion – Lymphoma can manifest as LETM. In cases of etiologically unclear atypical LETM in patients older than 40 years, a random skin biopsy (with subcutaneous adipose tissue) from the thigh and from the abdomen is strongly recommended as soon as possible. This may detect IVL and provide the possibility of prompt chemotherapy. In case of suspicion of lymphoma, parallel examination of the CSF by flow cytometry is also recommended. If skin biopsy is negative but lymphoma suspicion remains high, biopsy from other sites (bone marrow, lymph nodes or adrenal gland lesion) or from a simultaneously existing cerebral lesion is suggested, to exclude or prove diffuse large B-cell lymphoma, IVL, or a rare T-cell lymphoma.