Clinical Neuroscience

[ANIMAL MODELS OF CEREBRAL ISCHEMIA - TESTING THERAPEUTIC STRATEGIES IN VIVO]

ERDŐ Franciska, KONSTANTIN-ALEXANDER Hossmann

SEPTEMBER 30, 2007

Clinical Neuroscience - 2007;60(09-10)

[Acute cerebral ischemia is one of the leading causes of mortality and chronic disability worldwide. Animal models of focal (stroke-type) and global (cardiac arrest-type) ischemia have been established to investigate the morphological, functional and molecular consequences and to design therapeutic strategies for the improvement of ischemic injury. Despite highly beneficial effects in experimental studies, most human clinical trials were disappointing, suggesting inefficacies in the design and/or translation of animal experiments. In this review the pathophysiologically relevant particularities of ischemia models will be discussed to provide a rational basis for the proper selection of animal models for testing therapeutic strategies under experimental conditions.]

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Clinical Neuroscience

[PERSISTENT AKINETIC-RIGID SIDE EFFECTS OF NEUROLEPTICS MAY INDICATE WILSON'S DISEASE]

ASCHERMANN Zsuzsanna, SZALAY Ferenc, SCHMIDT Erzsébet, KOMOLY Sámuel, ILLÉS Zsolt

[Here we report two cases, where neuroleptic treatment provoked persistent akinetic-rigid symptoms resulting in the diagnosis of Wilson's disease. No liver function abnormalities suggested Wilson's disease in one of the cases. In both cases, the akinetic-rigid symptoms were originally attributed to side effects of neuroleptics, but symptoms persisted after discontinuation of treatment. In one of the cases, T2-weighted cranial MRI indicated bilateral hyperintense signals in the basal ganglia. Our cases suggest that in a subgroup of Wilson's disease, dopamin receptor antagonists may provoke akinetic-rigid neurological symptoms possibly due to the damage of dopaminergic neurons. Persistent akinetic-rigid side effects of neuroleptics in young patients thus require diagnostic tests to exclude Wilson's disease even in unsuspected cases.]

Clinical Neuroscience

[POSSIBLE ROLE OF THE BASAL GANGLIA IN THE GENERATION OF THE N30 POTENTIAL OF THE MEDIAN NERVE SOMATOSENSORY EVOKED POTENTIALS]

BENICZKY Sándor, NAGY Helga, VARGA Edina, VÖRÖS Erika, KÉRI Szabolcs, VÉCSEI László

[Background and purpose - The origin and afferentation of the frontal N30 component of the median nerve somatosensory evoked potentials (SEPs) have not yet been fully elucidated. The aim of this study was to assess the possible selective impairment of the N30 component in patients with lacunar infarcts of the basal ganglia as compared to patients with lacunar infarctions sparing the basal ganglia and to a group of healthy subjects. Methods - Median nerve SEPs were measured in ten patients with lacunar infarctions of the brain (but no cortical atrophy or leukoaraiosis) and 13 healthy volunteers. Four patients had lacunar infarctions affecting the basal ganglia and 6 patients had lesions affecting other structures. Results - In two patients with lesions affecting the head of the caudate nucleus, there was no identifiable N30 component on the affected side. In one patient with bilateral lesions of the globus pallidus, the amplitude of the N30 component was significantly reduced. In one patient with lesion of the tail of the caudate nucleus, the N30 component was unaffected. The amplitude of the N30 component was also reduced in two patients with frontal subcortical white matter lesions. In all the other subjects, we recorded normal N30 components on both sides. Conclusion - Our results further support the importance of the basal ganglia, especially the head of the caudate nucleus in the generation of the N30 component of the median nerve SEPs.]

Clinical Neuroscience

[IDIOPATHIC NOCTURNAL FRONTAL LOBE EPILEPSY - AN UNUSUAL EPILEPSY SYNDROME]

HALÁSZ Péter, SZŰCS Anna, KELEMEN Anna

[This paper provides an overview of the development of conceptions about nocturnal frontal lobe epilepsy syndrome and describes the electro-clinical characteristics, the identity of the genetic and sporadic variant, and the relationship of the EEG and clinical signs with NREM sleep specific features. The differential diagnostic difficulties and open questions on the pathomechanism are emphasized especially in relation with the lack of epileptiform EEG signs, circumsribed seizure onset zone and cognitive deficits. The relationship of frontal automatisms and NREM parasomnias are also discussed in relation of the place of nocturnal frontal lobe epilepsy among other epilepsies.]

Clinical Neuroscience

[SIMULTANEOUS CENTRAL AND PERIPHERAL NERVOUS SYSTEM INVOLVEMENT IN SYSTEMIC LUPUS ERYTHEMATOSUS]

ILNICZKY Sándor, KAMONDI Anita, ARÁNYI Zsuzsanna, VÁRALLYAY György, GAAL Barbara, SZIRMAI Imre, NAGY György

[Systemic lupus erythematosus is a frequent autoimmune disease, affecting several organs, including the brain, spinal cord and nerves. Cerebral vasculitis, transverse myelitis and polyneuropathy are the most common neurological manifestations. We report a case of a 46 years old woman who suffered incomplete transverse myelitis in her age of 44. After 2 years the second relapse presented with arthralgias, painful paraesthesias and weakness of the lower limbs. Neurological signs suggested involvement of the central and the peripheral nervous system. Based upon clinical and laboratory findings systemic lupus erythematosus was diagnosed. Magnetic resonance imaging revealed two hyperintense lesions on T2 weighted scans within the cervical spinal cord. The brain scan was normal. Protein content was slightly elevated in the cerebrospinal fluid, with normal cell count. Electrophysiological examinations diagnosed a subacute sensory-motor axonal polyneuropathy. On methylprednisolone treatment her condition improved. Simultaneous development of central and peripheral lesions of the nervous system in cases with systemic lupus erythematosus may lead to a challenge to establish the diagnosis.]

Clinical Neuroscience

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[The connection between the socioeconomic status and stroke in Budapest]

VASTAGH Ildikó, SZŐCS Ildikó, OBERFRANK Ferenc, AJTAY András, BERECZKI Dániel

[The well-known gap bet­ween stroke mortality of Eastern and Western Euro­pean countries may reflect the effect of socioeconomic diffe­rences. Such a gap may be present between neighborhoods of different wealth within one city. We set forth to compare age distribution, incidence, case fatality, mortality, and risk factor profile of stroke patients of the poorest (District 8) and wealthiest (District 12) districts of Budapest. We synthesize the results of our former comparative epidemiological investigations focusing on the association of socioeconomic background and features of stroke in two districts of the capital city of Hungary. The “Budapest District 8–12 project” pointed out the younger age of stroke patients of the poorer district, and established that the prevalence of smoking, alcohol-consumption, and untreated hypertension is also higher in District 8. The “Six Years in Two Districts” project involving 4779 patients with a 10-year follow-up revealed higher incidence, case fatality and mortality of stroke in the less wealthy district. The younger patients of the poorer region show higher risk-factor prevalence, die younger and their fatality grows faster during long-term follow-up. The higher prevalence of risk factors and the higher fatality of the younger age groups in the socioeconomically deprived district reflect the higher vulnerability of the population in District 8. The missing link between poverty and stroke outcome seems to be lifestyle risk-factors and lack of adherence to primary preventive efforts. Public health campaigns on stroke prevention should focus on the young generation of socioeconomi­cally deprived neighborhoods. ]

Clinical Neuroscience

[The Comprehensive Aphasia Test in Hungarian]

ZAKARIÁS Lilla, RÓZSA Sándor, LUKÁCS Ágnes

[In this paper we present the Comprehensive Aphasia Test-Hungarian (CAT-H; Zakariás and Lukács, in preparation), an assessment tool newly adapted to Hungarian, currently under standardisation. The test is suitable for the assessment of an acquired language disorder, post-stroke aphasia. The aims of this paper are to present 1) the main characteristics of the test, its areas of application, and the process of the Hungarian adaptation and standardisation, 2) the first results from a sample of Hungarian people with aphasia and healthy controls. Ninety-nine people with aphasia, mostly with unilateral, left hemisphere stroke, and 19 neurologically intact control participants were administered the CAT-H. In addition, we developed a questionnaire assessing demographic and clinical information. The CAT-H consists of two parts, a Cognitive Screening Test and a Language Test. People with aphasia performed significantly worse than the control group in all language and almost all cognitive subtests of the CAT-H. Consistent with our expectations, the control group performed close to ceiling in all subtests, whereas people with aphasia exhibited great individual variability both in the language and the cognitive subtests. In addition, we found that age, time post-onset, and type of stroke were associated with cognitive and linguistic abilities measured by the CAT-H. Our results and our experiences clearly show that the CAT-H provides a comprehensive profile of a person’s impaired and intact language abilities and can be used to monitor language recovery as well as to screen for basic cognitive deficits in aphasia. We hope that the CAT-H will be a unique resource for rehabilitation professionals and aphasia researchers in aphasia assessment and diagnostics in Hungary. ]

Clinical Neuroscience

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

Hyperhomocysteinemia in female migraineurs of childbearing ages

ALEMDAR Murat, SELEKLER Macit Hamit

Background and purpose - Migraine is a risk factor for ischemic stroke in women of childbearing ages. Previous researches revealed a higher prevalence of hyperhomocysteinemia in migraineurs. Possible differences on the frequencies of hyperhomocysteinemia between migraine with aura and migraine without aura could contribute the established variances in stroke risk between these migraine types. Therefore, we aimed to search if the frequency of hyperhomocysteinemia was different between these subtypes of migraine or not. Methods - We analyzed the findings of serum homocysteine levels in female migraineurs of 16-49 years old who admitted to our outpatient clinic. Results - Homocysteine level was elevated in 13.3% of study population. There were not any significant differences on median serum homocysteine levels between migraine with aura (8.0 mikromol/L) and without aura (8.5 mikromol/L). (p=0.426) The frequencies of hyperhomocysteinemia were also similar (9.1% versus 16.7%, respectively; p=0.373). Correlation analyses did not reveal any linear correlation between ages and homocysteine levels either in group of migraine with aura or in group of migraine without aura (p=0.417 and p=0.647, respectively). Similarly, any linear correlation between disease ages and homocysteine levels either in group of migraine with aura or in group of migraine without aura was not detected (p=0.359 and p=0.849, respectively). Conclusion - The median serum homocysteine levels and the frequencies of hyperhomocysteinemia are similar between migraine with aura and without aura in women of childbearing ages. Therefore, the variances on stroke risk ratios between these types of migraine are probably not originated from the differences of serum homocysteine status.

Clinical Neuroscience

[Hypertension and it’s therapy in acut phase of stroke]

KÁPOSZTA Zoltán, RÁCZ Klára

[The elevation of blood pressure above normal and premorbid values within the first 24 hours of symptom onset in patients with stroke is relatively common. This acute hypertensive response is usually managed by different group of physicians, including general practitioners, emergency physicians, neurologists, internists, intensivisists. Management strategies of this phenomenon vary considerably. The first consideration in blood pressure management in this clinical setting is to determine whether the patient might be a candidate for thrombolytic therapy. For those patients are not entitled to that therapy premorbide blood pressure values and the type of stroke are the key data for sufficient control of hypertension. In patients with chronic hypertension, the lower end of the autoregulation curve is shifted toward high pressure and an impaired autoregulation due to acute stroke may increase the risk for further brain tissue damage if the blood pressure is inadequately controlled. The current guidelines recommend lowering blood pressure in patients with an intracranial haemorrhage below 160- 180/100-105 mmHg, if the patient is normotensive, while the target level is 180/105 mmHg in hipertensive patients. However, in ischaemic stroke no treatment is recommended if systolic blood pressure <220 mmHg and/or diastolic blood pressure <120 mmHg in the acute stage. Clinical studies are rare which assess the effectiveness of different antihipertensive drugs in acute stroke. The first strong evidence came from the ACCESS (The Acute Candesartan Cilexetil Therapy in Stroke Survivors) trial which suggested that a 7-day course of candesartan after an acute ischaemic stroke significantly improves cardiovascular morbidity and mortality.]