Clinical Neuroscience - 2010;63(01-02)

Clinical Neuroscience

JANUARY 30, 2010

[How does the brain create rhythms?]

SZIRMAI Imre

[Connection was found between rhythmic cortical activity and motor control. The 10 Hz μ-rhythm and the 20-30 Hz bursts represent two functional states of the somatomotor system. A correspondence of the central μ-rhythm of the motor cortex and the physiological hand tremor (8-12 Hz) is presumed. The precise tuning of the motor system can be estimated by the frequency of repetitive finger movements. In complex tapping exercise, the index finger is the most skillful, the 3rd, 4th and 5th fingers keep rhythm with less precision. It was found that the organization of mirror movements depends on the cortical representation of fingers. Mirror finger movements are more regular if the subject begins the motor action with the 5th (small) finger. Concerning cortical regulation of finger movements, it was suggested that there are two time-keeping systems in the brain; one with a sensitivity above and another with a sensitivity below the critical frequency of 3 Hz. The preferred meter which helps to maintain synchronous finger movements is the cadence of 4/4 and 8/8. We observed that the unlearned inward-outward sequential finger movement was equally impaired in nonmusician controls and patients with Parkinson-disease. In movement disorders, the ability of movement and the “clock-mechanism” are equally involved. The polyrhythmic finger movement is not our inborn ability, it has to be learned. The “timer” function, which regulates the rhythmic movement, is presumably localised in the basal ganglia or in the cerebellum. The meter of the music is built on the reciprocal values of 2 raised to the second to fifth power (1/12, 1/22, 1/23, 1/24, 1/25). The EEG frequencies that we consider important in the regulation of cons-cious motor actions are approximately in the same domain (4, 8, 16, 32, 64 Hz). During music performance, an important neural process is the coupling of distant brain areas. Concerning melody, the musical taste of Europeans is octavebased. Musical ornaments also follow the rule of the gothic construction, that is: pursuit of harmony towards the single one rising from the unification of 8-4-2 classes. Leibnitz concerned music as the unconscious mathematics of the soul. Movement-initiating effect of music is used in rehabilitation of patients with movement disorders. The meter and rhythm have superiority over the melody. It is possible that rhythmic movements can be generated also in the absence of sensory input and the central oscillators can produce “fictive motor patterns”.]

Clinical Neuroscience

JANUARY 30, 2010

[Anterior cervical fusion on the lower cervical spine: own clinical experiences]

PAZDERNYIK Szilárd, SÁNDOR László, ELEK Péter, BARZÓ Pál

[Both acute and chronic instability of the cervical spine can be succesfully treated by anterior crevical fusion. The main goal is to create a spondylodesis through which the instable motion segments are fixed in the position defined by the surgeon. The spondylodesis is realised by the bone healing of the intervertebral space. The consolidation itself is facilitated by the operative stabilisation of the segments involved, and also by the implantation/transplantation of the osteoproductive/ osteoinductive materials. The sooner consolidation is achieved, the more likely it is to be able to avoid the material dependent complications and/or that of dislocation. So as to support this theory a retrospective clinical/radiological study was performed. During this the length and the safety of the consolidation was measured by applying various anterior cervical plating systems. A total of 485 patients having cervical injuries or degenerative disc disease were treated by anterior cervical plating. For bone transplantation partly pure autolog spongious partly autolog cortico-spongious morsalised bone chips, furthermore autolog tricortical bone block were applied. A standard protocoll was used for data collection, evaluation and also follow-up. The patients treated with plate systems were divided into 3 groups: Group 1: Non-locked H-plate system with autogeneous cancellous bone (155 trauma patients, for a total of 210 cervical motion segments, 1.35 segments/patients). Group 2: Non-locked H-plate system with tricortical autograft (167 patients, for a total of 290 cervical motion segments, 1.73 segments/patients). Group 3: Locked cervical plate system with tricortical autograft (73 patients, for a total of 110 cervical motion segments, 1.5 segments/patients). Patients treated with standalone cage belong to group 4. These cages were filled with autogenous cortico-spongiosus bone chips (90 patients, for a total of 90 cervical motion segments, 1.0 segments/patients). Evaluations included postoperative clinical, X-ray and CT examination, and follow-ups at 6, 16, 52, and 104 weeks. We established three grades, and classified the degree of bony fusion between the graft and vertebra: not-yet-fused, fused or non-union. When evaluating the results the following statements/observations were made: a) There is a fast and safe consolidation in the case of those patients that underwent dinamic disc osteosynthesis (p=0.00001). b) Whereas performing fixation with non-locked or locked screw plate systems and strutgrafted with tricortical autograft created prolonged healing requiring months and developed non-unions more often (non-locked screw-plate system versus locked screwplate system) (p>0.05). c) Using locked screw-plate fixation systems non-union rate in our study was 21%, suggesting that this form of fixation has only a limited use. d) In our study complete consolidation without pseudoarthrosis was achieved by using standalone cages filled with autolog cortico- spongiosus bone chips, but bony healing was delayed due to cage coating and the substitution of pure autogenous spongiosa for cortico-spongiosus bone chips. It is recommended to treat acute/chronic instability of the cervical spine both by using non-fixed plate system with autolog cancellosus bone and by standalone cage filled with cortico-spongiosus bone chips as well. It is worth keeping in mind that by applying this lattest an extra surgery to harvest the graft will be avoided.]

Clinical Neuroscience

JANUARY 30, 2010

[Extracellular matrix of intracerebral tumors with different invasion activity]

KLEKNER Álmos, VARGA Imre, BOGNÁR László, HUTÓCZKI Gábor, KENYERES Annamária, TÓTH Judit, HANZÉLY Zoltán, SCHOLTZ Beáta

[Objectives - Ineffective surgical and radiotherapy of glioblastoma is mainly due to its intensive infiltrating behavior. Contrarily, brain metastases of anaplastic carcinomas are well-circumscribed intracerebral lesions that can be easily exstirpated in most cases. The molecules of the extracellular matrix (ECM) play a pivotal role in the peritumoral infiltration. In this study the mRNA expression of the ECM components was investigated in two types of intracerebral malignoma with different invasion activity. Our aim was to identify the ECM molecules that are responsible for the different intensity of peritumoral infiltration of tumors from different origin. Methods - The mRNA expression of twenty-three ECM molecules was determined by quantitative reverse transcriptase polymerase chain reaction. Four pieces of glioblastoma and four pieces of intracerebral lung adenocarcinoma metastasis from neurosurgical operation were investigated. Immunohistochemical investigations were performed in case of five molecules. Results - The mRNA expression of nine molecules (brevican, neurocan, neuroglycan-C, syndecan-1,2,4, tenascin-C, versican and matrix-metalloproteinase-[MMP]2) differed significantly by comparison of the two tumor types. By immunohistochemistry, neurocan, syndecan, versican and MMP-2 showed alteration in staining intensity according to the mRNA expression, while MMP-9 showed higher staining intensity in the metastatic tumor. Conclusions - The identified molecules can play an important role in the different infiltration activity of tumors from different origin. Thus these ECM-components could serve as targets for anti-invasion therapy in the future.]

Clinical Neuroscience

JANUARY 30, 2010

[Posterior cortical atrophy (Benson-syndrome)]

RÓZSA Anikó, SZILVÁSSY Ildikó, KOVÁCS Krisztina, BOÓR Krisztina, GÁCS Gyula

[We present the characteristics of posterior cortical atrophy - a very rare cortical dementia - in a 69 year old woman’s case. Our patient’s symptoms began with a visual problem which was initially explained by ophthalmological disorder. After neurological exam visual agnosia was diagnosed apart from other cognitive disorder (alexia without agraphia, acalculia, prosopagnosia, constructional disorder, clock-time recognition disorder, dressing apraxia, visuospatial disorientation). The brain MRI showed bilateral asymmetric parieto-occipital atrophy which is characteristic of posterior cortical atrophy.]

Clinical Neuroscience

JANUARY 30, 2010

[Molecular genetic mutation analysis in Menkes-disease with prenatal diagnosis]

LÁSZLÓ Aranka, ENDREFFY Emőke, TÜMER Zeynep, HORN Nina, SZABÓ János

[Menkes disease (MD) is an X-linked recessive multisystemic lethal, heredodegenerative disorder. Progressive neurodegeneration and connective tissue disturbances with microscopically kinky hair are the main symptoms. Molecular genetic mutation analysis was made at a Hungarian male infant suffering from MD and prenatal diagnosis was done in this MD loaded family. Method - The 12th exon of ATP7A gene has been analyzed by dideoxy-finger printing (DDF), polymerase chain reaction (PCR), direct sequencing of exon 12. The specific mutation was screened from chorionic villi of the maternal aunt at the 14th gestational week. Results - In the exon 12th a basic pair substitution with Arg 844 His change was detected leading to very severe fatal missense mutation.]

Clinical Neuroscience

JANUARY 30, 2010

[Frontotemporal dementia, Pick’s disease]

ANDREW Kertesz

[A significant expansion of knowledge in the last few years, especially in the molecular biology of frontotemporal dementia (FTD) is summarized. This condition, formerly known as Pick’s disease and considered rare, is estimated to be 12-15% of all dementias and 30-50% early onset ones. The clinical picture is protean, mainly a behavioural and language impairment, but the extrapyramidal syndromes of CBD and PSP also belong. These seemingly different presentations converge, as one or other areas in the brain are affected. Less than half of the cases are tauopathies, the majority has been discovered to have a TDP-43 and most recently a FUS proteinopathy, shared with ALS, opening potential opportunities for pharmacological approaches to treatment. Tau and progranulin mutations on Ch-17 and some others, point to molecular mechanisms. A glossary is provided to navigate the complex terminology.]

Clinical Neuroscience

JANUARY 30, 2010