Search

In 24 adults and 29 children both with Gilles de la Tourette syndrome and in 24 control adults and 17 control children we studied auditory event-related potentials (ERP's) evoked in 2 different oddball paradigms: a passive listening paradigm (PLP) in which subjects had only to attend tones (260 standards, 40 deviants), followed by an active discrimination paradigm (ADP) in which subjects had to press a microswitch in response to the deviant tones. In the adult Tourette patients the PLP disclosed between 200-300 msec at all derivations (Fz, Cz, Pz, C3, C4, P3, P4) a significantly more negative activity than in the controls. In the Tourette children such a result was only found at Fz. In the ADP the differences between both adult groups disappeared, but the curves of the control children became now significantly more positive than those of the Tourette ones except at C3 and P3. Between 200-300 msec the curves of all 4 groups were significantly less negative in the ADP than in the PLP. This decrease in negativity was significantly larger in the adult Tourette patients than in the adult controls, but in the children groups the reverse occurred. It is hypothesized that the differences in amplitude between patients and controls and between both paradigms are due to differences in amplitude of an endogenous negative component overlapping the exogenous N100-N200 standard curve. Based on this hypothesis the results could suggest that one of the problems in Tourette syndrome is an increased attention to non-relevant stimuli.

Animal studies showed that benzodiazepines decrease the concentration of dopamine in the striatum. Benzodiazepines may therefore affect the treatment of Parkinson's disease. This study determined whether start of a benzodiazepine in patients on levodopa was followed by a faster increase of antiparkinsonian drug treatment.Data came from the PHARMO database, which includes information on drug dispensing for all residents of six Dutch cities. Selected were all patients aged 55 years and older who used levodopa for at least 360 days. The rate of increase of antiparkinsonian drug treatment was compared between starters of a benzodiazepine and controls who did not start a benzodiazepine with the use of Cox's proportional hazard model.Identified were 45 benzodiazepine starters (27 women, mean age 76.4 years) and 169 controls (83 women, 74.3 years). Antiparkinsonian drug treatment increased faster in the benzodiazepine group; relative risk was 1.44 (95% confidence interval 0.80-2.59).This study has not found any statistically significant increase in antiparkinsonian drug treatment when a benzodiazepine was started in a small population of chronic levodopa users.

Based on the recent discovery of co-localization of beta/A4 and cystatin C in cortical blood vessels of patients with cerebral hemorrhages due to sporadic amyloid angiopathy and patients with Alzheimer's disease we investigated the presence of these two proteins in the cortical blood vessels of patients suffering from hereditary cerebral hemorrhage with amyloidosis of the Dutch (n = 11) and the Icelandic (n = 2) type. The brains of three patients with sporadic cerebral amyloid angiopathy were also investigated. Blood vessels of the Dutch patients clearly showed immunostaining with beta/A4 as well as with cystatin C antibodies, whereas the blood vessels of Icelandic patients showed only staining with cystatin C. In one of the three sporadic amyloid angiopathy patients co-localization was shown as well. The co-localization of mutated beta/A4 with normal cystatin C in the Dutch patients suggests that cystatin C deposition occurs secondarily to beta/A4 deposition. This is probably also the case in sporadic amyloid angiopathy and Alzheimer's disease. Cystatin C deposition may play a role in the development of cerebral hemorrhages and leukoencephalopathy.

The effect of Tiapride on dyskinesia was evaluated in 12 patients with tardive dyskinesia in a double-blind controlled cross-over trial. The effect was measured by a Doppler-radar device and by counting the number of involuntary movements from video-recordings. Besides these methods, subjective assessments were made on analogue scales by family, nurses and attendant doctors. The subjective evaluation appeared to be useless because of many inconsistent answers. The quantitative methods revealed a significant diminution of the involuntary movements in the Tiapride therapy period (P less than 0.01). It appears that tiapride is an effective drug in the treatment of tardive dyskinesia. No clinically important side-effects have been observed. The drug appeared not to induce parkinsonism.

A simple and effective method is described to quantify involuntary movements. The method is based on the Doppler radar principle. Reproducibility of the method is demonstrated in a group of patients with Huntington's chorea and Tardive Dyskinesia. It is shown that the method correlates with clinical assessments, but is preferable because of its objectivity and simplicity.