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U Koehler

Publications and source records attributed to U Koehler.

At least 19 recordsLinked to original sources
PubMed2005

[Nocturnal long-term recording of breath sounds in patients with bronchial asthma -- a reasonable diagnostic option?].

Alterations in normal breath sounds are an important indication of pathophysiological processes in the bronchial system and the lung. In the presence of non-specific symptoms like dyspnea, wheezing or cough while sleeping it seems reasonable to make a nocturnal long-term recording of breath sounds. Thus specific auscultation phenomena can be recorded qualitative and particularly quantitative in the course. A mobile recording system provides a non-invasive monitoring at home which is independent of vigilance. Furthermore it can be used for follow-up examinations of medical interventions.

Asthma↗
PubMed2003

[Why is obstructive sleep apnea (OSA) a cardiovascular risk factor?].

Patients with obstructive sleep apnea (OSA) frequently suffer from cardiovascular diseases. Mechanisms like intrathoracic pressure variations, changes in blood gases (hypoxia), arousals and neurohumeral adaptation mechanisms, combined with breathing disorders are causing these cardiovascular sequelae. In particular repetitive hypoxemia and activation of the sympathetic nervous system have to be considered as stressors for the cardiovascular system. Special clinical findings should take OSA into consideration as a differential diagnosis. A systematic anamnesis with questions to daytime conditions (hypersomnia, decrease of performance), snoring and apneas while sleeping is easy to ascertain, and will lead to the correct diagnosis in more than 90% of cases. The extent and need for therapy should be assessed by three criteria: 1) daytime symptoms, 2) the extent of breathing disorder and 3) cardiovascular comorbidity.

Arousal↗
PubMed2003

[Acoustic follow-up of nocturnal bronchial obstruction therapy].

Long acting beta 2-agonists belong to the basic therapy of COPD. Especially patients with nocturnal respiratory problems may benefit from this therapy. Long term recording of lung sounds is a new method for quantitative measurements of bronchial obstructions. In combination with polysomnography an evaluation of cardiorespiratory parameters and sleep structure is possible. A total of 10 patients (8 male and 2 female) with moderate COPD (FEV1 58 +/- 11 %) and signs of bronchial obstruction were investigated. The combination of acoustic long term recording and polysomnography was done for 2 or 3 nights without and under therapy (long acting beta 2-agonist, 50 microg Salmeterol). In all patients we could find nocturnal bronchial obstruction events. Nocturnal wheezing time was reduced during therapy to 33 +/- 17 % (1. therapy night, n. s.) compared to 49 +/- 30 % without therapy (control night) and to 17 +/- 17 % (2. therapy night, n = 6, p < 0.05) vs. 51 +/- 30 % (control night, n = 6). Sleep efficiency and REM sleep increased (n. s.) under therapy, deep sleep stages NREM III/IV were nearly the same. Acoustic long term monitoring confirms the reduction of nocturnal bronchial obstructions under therapy with beta 2-agonists. A better sleep quality may be expected from the improvement of the respiratory situation during sleep.

Adrenergic beta-Agonists↗
PubMed2003

[Effect of subcutaneous fatty tissue on normal respiratory sounds].

Auscultation is an important, non-invasive and simple measure in the diagnosis of lung diseases that can detect sometimes pathological processes prior to radiography. Attempts have already been made to automatically detect characteristic pathological sounds, but a knowledge of potential influencing factors is a must for correct interpretation. In this study we have investigated the effect of the subcutaneous fat layer on normal lung sounds. This is of importance to determine corrective factors for the automatic detection of bronchial breathing in pneumonia. The lung sounds of 125 healthy people (55f, 70m) were digitally recorded at four different positions of the thorax (3. ICR paravertebral, 7. ICR medioscapular, all left and right). Evaluation was done separately for gender. The subcutaneous fat layer was measured with a Holtain Skinfold Caliper at the identical four recording positions. For a quantitative evaluation of the sounds we calculated the relative power of frequency bands 330-600 Hz and 60-330 Hz and their ratio. The relation between these parameters and the subcutaneous fat layer was analyzed with the Pearson correlation. The results of this study show that the influence of subcutaneous fat layer is negligible and can be ignored in the automatic detection of lung sounds.

Adipose Tissue↗
PubMed2002

Chromosome painting reveals that galagos have highly derived karyotypes.

The differences in chromosome number between Otolemur crassicaudatus (2n = 62) and Galago moholi (2n = 38) are dramatic. However, the total number of signals given by hybridizing human chromosome paints to galago metaphases is similar: 42 in O. crassicaudatus and 38 G. moholi. Many human chromosome homologs are found fragmented in each species, and numerous translocations have resulted in chromosomal syntenies or hybridization associations which differ from those found in humans. Only 7 human autosomes showed conserved synteny in O. crassicaudatus, and 9 in G. moholi. Both galago species have numerous associations or syntenies not found in humans: O. crassicaudatus has 11, and G. moholi has 21. The phylogenetic line leading to the last common ancestor of the two galago species accumulated 6 synapomorphic fissions and 5 synapomorphic fusions. Since the divergence of the two galago species, 10 Robertsonian translocations have further transformed the G. moholi karyotype, and 2 fissions have been incorporated into the O. crassicaudatus karyotype. Comparison with other primates, tree shrews, and other mammals shows that both galagos have karyotypes which are a mixture of derived and conserved chromosomes, and neither has a karyotype close to that of the proposed ancestor of all primates. Am J Phys Anthropol 117:319-326, 2002. Published 2002 Wiley-Liss, Inc.

Animals↗
PubMed2002

[Acoustic analysis of nocturnal bronchial obstruction].

Patients with obstructive pulmonary disease also have respiratory problems in sleep. The continuous acoustic lung sound detection together with a cardiorespiratory polysomnography allows a synchronous registration of bronchial obstruction as well as vigilance and respiratory parameters in sleep.A total of 20 patients (9 male and 11 female) with known obstructive airway disease and evident diurnal bronchial obstruction were investigated. We did a monitoring in all patients with a nocturnal continuous acoustic lung sound detection together with a cardiorespiratory polysomnography. The mean age was 55 +/- 12 years (range 23 to 74). In all patients acoustic nocturnal bronchial obstructions could be registered. The wheezing-time (time portion of wheezing while sleeping) was 32.1 +/- 27.4 % (mean +/- SD). We could not proof reliable a rhythm of bronchial obstructions. Only 3 patients had increased bronchial obstructions between 3 and 5 AM. The sleep structure was disturbed in 16 of 20 patients with reduced deep sleep, REM sleep and prolonged sleep latency. Knowing about nocturnal bronchial obstructions helps to adapt the antiobstructive therapy. One can expect that an improvement of the respiratory situation also improves sleep quality.

Adult↗
PubMed2002

[Continuous acoustic monitoring of nocturnal bronchial obstructions].

Patients with bronchial asthma often have respiratory problems in sleep. The effects of bronchial obstructions while sleeping have been analysed in some studies. For an exact assessment the sleep itself must not be disturbed by the method. The continuous acoustic lung sound detection is such a method. It helps to assess the circadian rhythm during antiobstructive therapy which may lead to a better sleep quality and daytime fitness.

Airway Resistance↗
PubMed2002

Detection of bronchial breathing caused by pneumonia.

The classic auscultation with stethoscope is the established clinical method for the detection of lung diseases. The interpretation of the sounds depends on the experience of the investigating physician. Therefore, a new computer-based method has been developed to classify breath sounds from digital lung sound recordings. Lung sounds of 11 patients with one-sided pneumonia and bronchial breathing were recorded on both the pneumonia side and on contralateral healthy side simultaneously using two microphones. The spectral power for the 300-600 Hz frequency band was computed for four respiratory cycles and normalized. For each breath, the ratio R between the time-segments (duration = 0.1 s) with the highest inspiratory and highest expiratory flow was calculated and averaged. We found significant differences in R between the pneumonia side (R = 1.4 +/- 1.3) and the healthy side (R = 0.5 +/- 0.5; p = 0.003 Wilcoxon-test) of lung. In 218 healthy volunteers we found R = 0.3 +/- 0.2 as a reference-value. The differences of ratio R (delta R) between the pneumonia side and the healthy side (delta R = 1.0 +/- 0.9) were significantly higher compared to follow-up studies after recovery (delta R = 0.0 +/- 0.1, p = 0.005 Wilcoxon-test). The computer based detection of bronchial breathing can be considered useful as part of a quantitative monitoring of patients at risk to develop pneumonia.

Auscultation↗
PubMed2001

GTG banding pattern on human metaphase chromosomes revealed by high resolution atomic-force microscopy.

Surface topography of human metaphase chromosomes following GTG banding was examined using high resolution atomic force microscopy (AFM). Although using a completely different imaging mechanism, which is based on the mechanical interaction of a probe tip with the chromosome, the observed banding pattern is comparable to results from light microscopy and a karyotype of the AFM imaged metaphase spread can be generated. The AFM imaging process was performed on a normal 2n = 46, XX karyotype and on a 2n = 46, XY, t(2;15)(q23;q15) karyotype as an example of a translocation of chromosomal bands.

Azure Stains↗
PubMed2000

[Eosinophilic myocarditis in Churg-Strauss syndrome. A rare cause of left heart decompensation with lung edema].

HISTORY: A 50-year-old woman was admitted because of marked dyspnoea at rest and signs of left heart failure with pulmonary oedema. 9 years ago, the diagnostic constellation of bronchial asthma, polyneuropathy, pericardial effusion and eosinophilia had indicated Churg-Strauss syndrome. Since then she had remained symptom-free under maintenance doses of azathioprine (for 2 years) and gradually reduced doses of steroids. INVESTIGATIONS: Chest X-ray showed signs of pulmonary congestion and cardiomegaly, echocardiography demonstrating enlargement of the left heart with marked impairment of ventricular function, and both revealed pericardial effusion. The electrocardiogram showed complete absence of R waves and ST elevation in leads V1-V5. Coronary angiography excluded coronary artery disease. Myocardial biopsy contained signs of active but no longer acute myocarditis with eosinophilic tissue infiltration and microgranulomas. White blood cell count was normal, but there was marked eosinophilia (39%). IgE was elevated (601 kIU/l). DIAGNOSIS, TREATMENT AND COURSE: In view of the good therapeutic effects 9 years ago, this relapse of Churg-Strauss syndrome with eosinophilic myocarditis was again treated with azathioprine and steroids. In addition, diuretics, digitalis and ACE-inhibitors successfully treated the heart failure. In the course of treatment the signs of inflammation, including the eosinophilia, regressed or became normal. CONCLUSION: After a 10-year remission without complication of a Churg-Strauss syndrome the onset of cardiac signs is the decisive long-term prognostic factor.

Biopsy↗
PubMed2000

Outcome of patients with sleep apnea-associated severe bradyarrhythmias after continuous positive airway pressure therapy.

Twenty-nine patients in whom severe bradyarrhythmias occurred exclusively during obstructive sleep apnea and in whom advanced sinus node disease or atrioventricular conduction system dysfunction had been excluded by invasive electrophysiologic evaluation were prospectively followed on nasal continuous positive airway pressure. During 54 +/- 10 months follow-up, no syncope and no sudden deaths were observed, suggesting that patients with sleep apnea-associated bradyarrhythmias and a normal electrophysiologic study appear to have a favorable prognosis with continuous positive airway pressure.

Bradycardia↗