Biomedical subjects

S von Nessen

Publications and source records attributed to S von Nessen.

3 recordsLinked to original sources

PubMed2000

[Narcolepsy. An illness in transition].

The signs of narcolepsy have been known since the last century and the tetrad of symptoms was described 50 years ago: excessive sleepiness, cataplexy, sleep paralysis, and hallucinations. Polysomnography typically shows decreased sleep and REM sleep latency, and laboratory testing reveals a high association with the human leucocyte antigens (HLA) DQB1*0602 and DQA1*102. Actual studies suggest disturbances in the orexin (hypocretin) neurotransmitter system. However, the exact pathophysiology is still unclear. In Germany, about 1500 patients diagnosed with narcolepsy are known. The prevalence in Caucasian populations is estimated at 50/100,000. Thus, the number of undiagnosed patients is likely to be high.

Cross-Sectional Studies↗

PubMed1996

[Subjective diurnal fatigue and sleep deprivation response].

29 major depressive patients, the majority suffering from a melancholic subtype and typical diurnal variation of mood, rated subjective tiredness on a 100 mm analogous scale before and after total sleep deprivation (TSD). In study A every four hours during the day before and after TSD and every 2 hours during the TSD-night ratings were performed, in study B at 8.00 a.m. before and after TSD. The mean response rate was 55.2% in the 2 studies. In study A subsequent responders were less tired during the afternoon before TSD. Responding patients were more alert the morning after sleep deprivation than non-responders. A higher inter-individually variability of tiredness ratings in responders before and after sleep deprivation was found in study B, assuming an arousing property and a greater variability in subjective arousal at least during the morning hours. In summary the determination of the subjective arousal level may help to predict response.

Adult↗

PubMed1995

[Structure of wakefulness of depressed patients before and after therapeutic sleep deprivation].

Responders spent more time in active wakefulness than non-responders. Responders after TSD also spent significantly less time in substage C than non-responders, even before TSD. Parallel to the decrease of substage C, substage B slightly, but not significantly increased in responders after TSD. The Hamilton-scores before TSD correlated significantly with the time spent in substage C. Our system of scoring polygraphically defined waking stages, which combine electrophysiological, behavioral and cognitive aspects of the waking states in a setting comparable a every-day condition, differentiated responders and non-responders to sleep deprivation therapy. Thus it may serve as an useful tool to further elaborate wakefulness within the sleep-wake-cycle with special reference to chronotherapeutic interventions.

Adult↗