0000000000402417

AUTHOR

Jürgen Bierbrauer

Automated determination of clozapine and major metabolites in serum and urine.

Clozapine is an atypical neuroleptic that is increasingly used for the treatment of schizophrenia. An automated method was developed for the routine quantification of clozapine and its major metabolites, N-desmethylclozapine and clozapine N-oxide, in human serum and urine by column switching and online high-performance liquid chromatography with ultraviolet detection. The method included adsorption of clozapine and its metabolites on a cyanopropyl-coated clean-up column (10 microns; 10 mm x 4.0 mm ID), washing interfering serum constituents to waste by deionized water, and, after column switching, separation on C18 ODS Hypersil reversed-phase material (5 microns; 250 mm x 4.6 mm ID). The co…

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Increased frequency of migraine in narcoleptic patients

We explored the relationship between narcolepsy and different types of headaches. We interviewed 68 patients with idiopathic narcolepsy for the presence of headache symptoms based on the criteria of the International Headache Society (IHS). Eighty-one percent of the patients reported headaches that warranted an IHS headache diagnosis. Fifty-four percent of the patients (64% women, 35% men) had migraine with all IHS criteria fulfilled.

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Increased prevalence of obesity in narcoleptic patients and relatives

Increased Body Mass Indices (BMIs), increased prevalences of non insulin-dependent diabetes and sleep apnoe syndrome have been reported to be associated with narcolepsy. Our objective was to explore and possibly confirm the association of narcolepsy and increased BMI. In addition, we addressed the question whether increased BMIs also occur in relatives of narcoleptic patients. Together with narcolepsy-related clinical parameters we measured body weight and height of 132 narcoleptic patients who agreed to participate in our narcolepsy research program. In addition, 52 first degree relatives of 22 index patients, mostly from multiplex families, were included in the study. Data were compared t…

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Visual memory in Alzheimer patients: effects of practice, retention interval and severity of cognitive decline.

The study was aimed at estimating the effect size of practice, retention interval and dementia severity on free recall performance in Alzheimer patients. Patients met DSM-III-R criteria for dementia of Alzheimer type. Different picture sets were presented on 4 days. The forgetting curves on different days were compared using ANOVA for repeated measurements. Practice had a minor, but significant negative effect on recall performance explaining 1% of the variance in recall performance. The retention interval varied between zero and 24 h explaining 23% of the total variance. Dementia severity explained 52% of the variance. For the development of memory improvement strategies in Alzheimer patie…

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