Clinical Neuroscience

[THE SIGNIFICANCE OF CHLAMYDIA PNEUMONIAE IN SELECTED NEUROLOGIC DISORDERS]

HORVÁTH Zoltán, VÉCSEI László

JANUARY 30, 2006

Clinical Neuroscience - 2006;59(01-02)

[Chlamydia pneumoniae has recently been implicated in the pathogenesis of several neurological diseases. As an intracellular parasite with its unusual life cycle it is able to circumvent the immune system and to persist in the organism. It has the ability to modify the function of the infected cell and supposedly induce autoimmune reactions. These properties can make it pathogenic in several chronic neurological diseases including multiple sclerosis, atherosclerosis, stroke, Alzheimer dementia and giant cell arteriitis. The evaluation of the available, often contradictory, data that are based on various different methods is not easy. The importance of the issue is enhanced by the potential need for antibiotic treatment.]

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Clinical Neuroscience

[COMPLEX TREMOR ANALYSIS FOR THE DIFFERENTIAL DIAGNOSIS OF ESSENTIAL TREMOR AND PARKINSON’S DISEASE]

FARKAS Zsuzsanna, CSILLIK Anita, PÁLVÖLGYI László, TAKÁCS Annamária, SZIRMAI Imre, KAMONDI Anita

[Objective - Tremor is the most common movement disorder which is most often either essential or caused by Parkinson’s disease. The differentiation of these disorders at the initial stage may be difficult. Objective assessment of the efficacy of tremor medications is only possible by instrumental measurements. The aim of this study was to determine whether the computer assisted tremor analysis system CATSYS 2000 can help in the differentiation of parkinsonian from essential tremor. Methods - The rhythmicity and maximal frequency of fast alternating hand and finger movements, simple reaction time and postural instability were recorded in healthy controls (n=18), patients with Parkinson’s disease (n=39) and essential tremor (n=37). Data were digitally converted and statistically analyzed. Results - Tremor intensity, median frequency and frequency distribution showed characteristic differences in the three groups. Performance in fast alternating movements of hands and fingers were significantly worse in both tremor groups compared to the healthy controls. Conclusions - The data also indicated that quantitative measurements of tremor parameters must be performed on both sides, because the presence of significant side differences support the diagnosis of Parkinson’s disease. The method presented can be used to objectively analyze tremor and performance in rhythmic movements. The results show that it helps to differentiate parkinsonian from essential tremor as well as to predict disease course and the effectiveness of therapy. Multivariate statistical analysis of tremor and movement performance also provides an opportunity to study the pathogenesis of human tremor.]

Clinical Neuroscience

[Neurosurgical ways…]

CSÓKAY András

Clinical Neuroscience

[The potential role of spinal ketamine in multi-component antinociception]

JOÓ Gabriella

Clinical Neuroscience

[CONGRESS CALENDAR]

[Congress calendar 2006;59(01-02)]

Clinical Neuroscience

[A NEURO-MECHANICAL TRANSDUCER MODEL FOR CONTROLLING JOINT ROTATIONS AND LIMB MOVEMENTS]

LACZKÓ József, KERRY Walton, RODOLFO Llinas

[Here we report on the development of an integrated general model for the control of limb movements. The model computes muscle forces and joint rotations as functions of activation signals from motoneuron pools. It models the relationship between neural signals, muscle forces and movement kinematics by taking into account how the discharge rates of motoneuron pools and the biomechanical characteristics of the musculoskeletal system affect the movement pattern that is produced. The lengths and inertial properties of limb segments, muscle attachment sites, the muscles’ force-length, force-frequency and force-velocity (of contraction) relationships, as well as a load parameter that simulates the effect of body weight are considered. There are a large number of possible ways to generate a planned joint rotation with muscle activation. We approach this “overcompleteness problem” by considering each joint to be controlled by a single flexor/extensor muscle pair and that only one of the two muscles is activated at a given time. Using this assumption, we have developed an inverse model that provides discharge rates of motoneuron pools that can produce an intended angular change in each joint. We studied the sensitivity of this inverse model to the muscle force-length relationship and to limb posture. The model could compute possible firing rates of motoneuron pools that would produce joint angle changes observed in rats during walking. It could also compare motoneuron activity patterns received for two different hypothetical force-length relations and show how the motoneuron pool activity would change if joints would be more flexed or extended during the entire movement.]

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The applications of transcranial Doppler in ischemic stroke

FINNSDÓTTIR Herdis, SZEGEDI István, OLÁH László, CSIBA László

Background: This overview provides a summary of the applications of transcranial Doppler (TCD) in ischemic stroke. Results: A fast-track neurovascular ultrasound protocol has been developed for detecting occlusion or stenosis. The technique is more reliable in the carotid area than in the posterior circulation. By monitoring the pulsatility index the in­crea­sed intracranial pressure can be diagnosed. TIBI score was developed for grading residual flow. TCD has been shown to accurately predict complete or any recanalization. Regarding recanalization, TCD has a sensitivity of 92%, a specificity of 88%, a positive predictive value of 96%, a negative predictive value of 78% and an overall accuracy of 91%, respectively. Sonothrombolysis seemed to be a promising application but randomized controlled trials have shown that it does not improve clinical outcome. TCD examination can detect microembolic signals (MES) which are associated with an increased risk of stroke. Micro­em­boli were detected in symptomatic and asymptomatic carotid artery stenosis and during carotid endarterectomy. The number of microemboli can be decreased by antithrombotic therapy. Contrast en­chan­ced examination and Valsalva maneuver with continuous TCD monitoring can accurately screen for right-to-left shunt.

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

[Family planning in multiple sclerosis: conception, pregnancy, breastfeeding]

RÓZSA Csilla

[Family planning is an exceptionally important question in multiple sclerosis, as women of childbearing age are the ones most often affected. Although it is proven that pregnancy does not worsen the long-term prognosis of relapsing-remitting multiple sclerosis, many patients are still doubtful about having children. This question is further complicated by the fact that patients – and often even doctors – are not sufficiently informed about how the ever-increasing number of available disease-modifying treatments affect pregnancies. Breastfeeding is an even less clear topic. Patients usually look to their neurologists first for answers concerning these matters. It falls to the neurologist to rationally evaluate the risks and benefits of contraception, pregnancy, assisted reproduction, childbirth, breastfeeding and disease modifying treatments, to inform patients about these, and then together come to a decision about the best possible therapeutic approach, taking the patients’ individual family plans into consideration. Here we present a review of relevant literature adhering to international guidelines on the topics of conception, pregnancy and breastfeeding, with a special focus on the applicability of approved disease modifying treatments during pregnancy and breastfeeding. The goal of this article is to provide clinicians involved in the care of MS patients with up-to-date information that they can utilize in their day-to-day clinical practice. ]

Clinical Neuroscience

[Controversies in neurology: Diagnosis, follow up and therapy of multiple sclerosis with pathomechanismal approach]

VÉCSEI László

[The clinical boundaries between the relapsing and progressive course of multiple sclerosis are often indistinct. Despite the variable patterns of evolution, there are no biological reasons for discerning different multiple sclerosis phenotypes. Indeed, both primary progressive and secondary forms of the disease share similar pathological features in respect of the extent of inflammatory infiltrates, axonal damage, and cortical demyelination. The data indicating that primary progressive multiple sclerosis is preceded by an asymptomatic relapsing remitting phase. The proposed definition of secondary progressive multiple slcerosis, the attainment of at least EDSS of 4 is required to mark the transition to the progressive phase. Therefore, the clinical progress can be uncovered in the early phase of the disease. Furthermore, a continuous progression independent of relapsing activity is commonly observed during the relapsing remitting phase. A continuous smouldering process underpins the subtle clinical deterioration, which stands out as an important unmet treatment target. Concerning cognitive dysfunction of the patients pro-inflammatory cytokines have been associated with worse cognition in active multiple sclerosis, and this inflammatory milieu could also contribute to altered mentation during relapses. Therefore, long before people with multiple sclerosis become physically disabled, they have usually acquired hidden disabilities related to cognitive impairment. Silent progression appears during the relapsing remitting phase and it associates with brain atrophy. This suggests that the same process that underlies secondary progressive multiple sclerosis likely begins far earlier than is generally recognized. This supports a unitary view of multiple sclerosis biology. ]

Clinical Neuroscience

[Current questions of multiple sclerosis: the secunder progressive form of the disease]

VÉCSEI László

[Recent data suggest that long-term worsening is common in relapsing-remitting multiple sclerosis patients and is largely independent of relapses or new lesion formation on brain MRI. The current definition of secunder progressive multiple sclerosis is worsening of disability independent of relapses over at least 6-month interval. Early focal inflammatory disease activity and spinal cord lesion are predictors of very-long term disease outcomes in relapse - onset multiple sclerosis. The potential of PET imaging to visualize hidden inflammation in MS brain in vivo is an important contribution for better understanding the progression of the disease. Therefore, PET imaging is a promising tool in detecting the conversion from relapsing remitting multiple sclerosis to secunder progressive form of multiple sclerosis. Furthermore, neuro-axonal damage is the pathological substrate of permanent disability in different neurological disorders including multiple sclerosis. The neurofilament proteins have promise in this context because their levels rise upon neuro-axonal damage not only in the cerebrospinal fluid but also in blood. Patients with increased serum levels of neurofilament at baseline, independent of other clinical and MRI variables, experience significantly more brain and spinal cord volume loss over 2 years and 5 years of follow-up. The kynurenine-pathway abnormalities may be associated with the swich from early-mild stage multiple sclerosis to debilitating progressive forms of the disease. Analysis of these metabolites in serum may have application as multiple sclerosis disease biomarkers. Free radical action has been suggested as a causal factor in the illness. Increased free radical production and consumption of the scavenger molecules were found during the active phase of the disease. Based on the clinical findings (EXPAND Study) and pathomechanism of the disease siponimod is approved by the US Food and Drug Administration for the treatment of relapsing remitting forms of multiple sclerosis, to include secunder progressive multiple sclerosis with active disease, relapsing-remitting multiple sclerosis and clinically isolated syndrome.]