Biomedical subjects

K Meier-Ewert

Publications and source records attributed to K Meier-Ewert.

At least 37 records · Page 2Linked to original sources

PubMed1988

Cellular approach for detecting narcolepsy-specific alterations in DR2 haplotypes.

In an attempt to detect disease-associated genetic variations and/or exogenously induced alterations in DR2 haplotypes of narcolepsy patients, primed lymphocytes (PLs) were generated in nine families against DR2 haplotypes of narcolepsy patients and healthy family members. Twenty-four PL reagents were obtained and restimulated by cells of unrelated narcolepsy patients and DR2/Dw2-positive healthy individuals. The mean restimulation rates triggered by cells of patients or healthy controls, respectively, never differed significantly. In primary MLC as well as PLT combinations of patients and their HLA-identical siblings no significant stimulation was observed in both directions. We conclude that narcolepsy-specific alterations of class II molecules cannot be cellularly detected or do not exist on peripheral lymphocytes.

Female↗

PubMed1988

[ENT medical findings in obstructive sleep apnea syndromes].

Correlations between the manifestation of obstructive sleep apnoea syndrome (OSAS) and anatomical or functional changes in the upper respiratory tract remain controversial. The correlation between obstruction of the upper respiratory tract and the degree of sleep apnoea syndrome was investigated in 60 patients with obstructive sleep apnoea (diagnosed by polysomnography) and in 55 healthy controls. After clinical examination, rhinomanometry and determination of the size of the lower jaw and oropharynx, the motility of the pharyngeal walls during Mueller's manoeuvre was evaluated by flexible endoscopy. No significant anatomical or functional differences were observed between OSAS patients and healthy controls. There was no correlation between the degree of OSAS (expressed by the apnoea index) and pharyngeal size. Although no specific statement concerning diagnosis or degree of OSAS can be made on the basis of an otolaryngological examination, OSAS patients should always undergo otolaryngological examination to exclude pharyngeal disease.

Airway Obstruction↗

PubMed1987

Rapid eye movements, muscle twitches and sawtooth waves in the sleep of narcoleptic patients and controls.

Seventeen unmedicated patients with narcolepsy-cataplexy and 17 age- and sex-matched controls were recorded polygraphically for 3 consecutive nights. Rapid eye movements (REMs), m. mentalis twitches and sawtooth waves in the EEG were visually scored. REM and twitch densities during REM sleep were significantly higher in the patients than in the controls. The distribution pattern of REMs and twitches was altered in the patients: twitch density peaked in the first REM period and density of REMs showed an even distribution across all the REM periods of the night. In the controls both REM and twitch density increased from the first to the second REM period. We therefore assume that in the narcoleptics phasic activity of REM sleep is disinhibited. Densities of REMs, twitches and sawtooth waves did not correlate with one another in patients and controls. They appear to be independently regulated. The REM periods of the patients contained 3 times as many waking epochs as those of the controls. This suggests that in narcolepsy the transition REM/waking is selectively facilitated. The REM/NREM ratio of twitch and sawtooth wave densities was the same in patients and controls.

Adult↗

PubMed1987

Possible male segregation distortion of DR2 haplotypes in narcolepsy patients.

Segregation of disease-associated DR2-linked haplotypes from patients with narcolepsy was studied in 18 German families. Of these, 13 were informative, as transmission could be traced from DR2 heterozygous patients to their healthy offspring. Although the composition of extended haplotypes was equal in males and females, DR2 was transmitted to 78.6% of the offspring by diseased fathers but only to 57.1% by diseased mothers. Compared to an expected 1:1 ratio according to Mendelian segregation this means a statistically significant deviation (p less than or equal to 0.03) for male but not for female patients. In contrast, transmission distortion was not observed with 30 DR2 haplotypes in 27 healthy families. These data represent a new example of male segregation distortion in an HLA-associated disorder.

Female↗

PubMed1986

[Therapy of obstructive sleep apnea syndrome].

Symptomatology and sequelae, as well as diagnosis and therapy of the obstructive sleep apnea syndrome are discussed. The Esmarch prosthesis, which we developed for the prosthetic treatment of obstructive sleep apnea syndrome, was tested in 7 patients. Patients were polysomnographically recorded during two sequential nights with and without Esmarch prosthesis. All apnea parameters improved significantly (apnea time by 78%, apnea index by 67% of baseline values). The mean duration of the remaining apnea phases diminished by 31%. Improvement of O2 saturation of haemoglobin and O2 partial pressure in the tissue paralleled that of the apnea parameters. The severely disturbed sleep profile of the patients showed a clear tendency towards normalization. The Esmarch prosthesis is an efficient method for the treatment of the obstructive sleep apnea syndrome.

Adult↗

PubMed1986

HLA and narcolepsy in a German population.

In this paper the first MHC data including HLA-A, B, C, DR, DQ and complement BF, C4A, C4B determinants in German narcoleptics are presented together with the first family studies in European Caucasoids. 57 out of 58 unrelated patients (98.3%) were positive for DR2 and DQw1, respectively. In contrast to all other reports, one patient with typical signs of narcolepsy was found to be DR2/DQw1 negative. Data showing significant increase in the frequency of B7, and normal frequencies of B35 were discordant with data from Japanese patients. Definition of the extended DR2 linked haplotypes, deduced from 6 families, revealed that 5 out of 12 were DQw1, DR2, BFS, C4B1, C4A3, B7 (Cw7), while 11/12 had DR2, DQw1, BFS, C4A3, C4B1 in common. In one multiple case family two genotypically different DR2 haplotypes were identified in affected siblings. Results from the family study were concordant with a dominant mode of inheritance with incomplete penetrance of a hypothetical disease susceptibility gene.

Complement C4↗

PubMed1985

Propranolol: long-term treatment in narcolepsy-cataplexy.

Forty-eight sequential narcoleptic patients were treated with propranolol (80-240 mg/day) for an average period of 18.4 months. Initially all patients received single drug therapy; after 10 days or longer, however, 50% of patients also received tricyclics or stimulants because propranolol alone did not sufficiently suppress the narcoleptic symptoms. Fifty percent of patients judged the initial effectiveness of propranolol on daytime sleepiness to be good to very good; in these patients the effects seemed comparable to that of pemoline. Within 6 months, however, the effectiveness started to decrease, and after 26 months only 8% (2 out of 24) of those patients taking the single drug were satisfied with propranolol therapy alone. Side effects included disturbed night sleep, decreased blood pressure, increased lethargy, allergic skin rash, and asthma; 58% of the patients dropped out of the study after 26 months. Vigilance tests during the first 4 months (16 patients) showed significant improvements in all test criteria, including a shorter reaction time. All-night polygraphic electroencephalogram recordings of 14 patients on the eighth and ninth day of medication showed that average total sleep time decreased by 5.7%, but other sleep characteristics did not change significantly.

Arousal↗

PubMed1983