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P Wichert

Publications and source records attributed to P Wichert.

18 recordsLinked to original sources

Effects of selective tachykinin-receptor antagonists on tachykinin-induced airway mucus secretion in the rat.

Tachykinins like substance P (SP), neurokinin A (NKA), neurokinin B (NKB) differentially stimulate airway mucus secretion with the following rank order of potency in rat trachea: SP>NKA>NKB. These differential actions are most likely due to different affinities to the tachykinin receptors, termed neurokinin (NK)(1), NK(2)and NK(3). In this study we characterized the receptor subtype responsible for the differential secretagogue effects in rat trachea by means of selective receptor antagonists and receptor agonists.SR 140333 [NK(1)-antagonist] completely inhibited SP action (283,29+/-21, 12%-->84,53+/-4, 09%; P<0,01) and significantly reduced the effects of NKA (179,08+/-17,34%-->118,86+/-6,7%; P<0,01) and NKB (171,89+/-5, 75%-->109,5+/-4,11%; P<0,01). SR 48968 [NK(2)-antagonist] did not affect SP action, but reduced the effects of NKA and NKB. SR 142801 [NK(3)-antagonist] did not change any effect of SP, NKA or NKB. [Sar(9)]SP (NK(1)-agonist) caused strong dose-dependent secretagogue effects similar to SP, [betaAla(8)]NKA (NK(2)-agonist) showed only slight and [Pro(7)]NKB (NK(3)-agonist) no effects. The present data suggest that the secretagogue effects elicited by tachykinins in rat trachea are mediated via NK(1)receptors.

Animals↗

Assessment of the nocturnal blood pressure relative to sleep stages in patients with obstructive sleep apnea.

To determine the mean blood pressure relative to sleep stages, two nocturnal cardiorespiratory polysomnographs were recorded in 60 male patients with hypertension and obstructive sleep apnea (OSA). The mean age was 50.2 years, the BMI 32.0 kg/m2, the respiratory disturbance index (RDI) 44, and the blood pressure by the WHO protocol 158/98 mm Hg. A new evaluation program was used to determine the invasively measured mean arterial pressure (mean +/- SEM) and heart rate (mean +/- SEM) during sleep (mean total sleep time 361 +/- 48 min) referred to sleep stages 1 (99.5 +/- 1.5 mm Hg/67.6 +/- 1.1 bpm), 2 (98.7 +/- 1.6 mm Hg/66.6 +/- 1.1 bpm), 3 (97.6 +/- 1.8 mm Hg/67.4 +/- 1.3 bpm), and 4 (97.6 +/- 2.2 mm Hg/66.3 +/- 1.6 bpm) and to REM sleep (103.3 +/- 1.7 mm Hg/68 +/- 1.2 bpm) as 1 s mean values and to compare them with the waking state (98.3 +/- 1.6 mm Hg/83.6 +/- 1.1 bpm). There was no physiological fall in blood pressure in patients with pronounced OSA. Sleep-stage-specific analysis of invasive continuous blood pressure signals is the gold standard. The sleep structure is disturbed less than with other methods.

Adult↗

[Errors and risks in administration of nasal respiratory therapy of obstructive sleep apnea].

Over a period of 1 year we observed in our sleep laboratory in 502 patients with sleep related breathing disorders several side effects of positive airway pressure treatment, furthermore we observed in 5 patients unexpected dangerous complications due to the application of CPAP and BIPAP. We observed mask leakages which lead to insufficient positive airway pressure-therapy and an occurence of short central apnoeas during NREM sleep after arousal or wakefulness periods. Finally we observed in 5 patients during treatment with CPAP and BIPAP an unexpected appearance of long central apnoeas up to 110s and central hypoventilations up to 5 min accompanied by excessive hypoxaemia (SaO2 < 20%) and cardiac arrhythmias. We conclude that in the treatment of obstructive sleep apnoeas we have to expect in 1-2% complications of the positive airway pressure treatment itself. To avoid life endangered complications the first night application should be done only in conventional sleep laboratories.

Equipment Failure↗

[Allergic alveolitis].

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Alveolitis, Extrinsic Allergic↗

[Serum endothelin in patients with Raynaud syndrome before and following cold provocation].

To determine wether there is a pathogenetic effect of endothelin (ET) in vasoconstriction in Raynaud's phenomenon, plasma-endothelin and it's association to extent of vasoconstriction was measured before and after digital cooling. Only in cases with massive vasoconstriction ET rose significantly after cooling. In conclusion ET seems to be involved in the pathogenesis of RS, whereas the exact pathomechanism remains unclear.

Cold Temperature↗

[Assessment of the MESAM and Biox 3700 early warning methods for the diagnosis of sleep-related respiratory disorders in young men].

We can use pulse oximetry as a method for diagnosis of the sleep apnoea syndrome, as well as L-EKG, MESAM II and the actigraph. In this study MESAM II and pulse oximetry were combined for finding out discrete sleep-related breathing disorders. The results were compared with polysomnography. 5 (15.1%) of 32 patients had an index of apnoea (AI) greater than 10, whereas 4 (12.1%) patients showed an AI greater than 5. All of the patients with positive signs in MESAM II/pulse oximetry had an AI greater than 5 in polysomnography, whereas non of the patients with negative signs in MESAM II/pulse oximetry had an AI greater than 5 in polysomnography.

Adult↗

[Which factors promote chronic alveolar hypoventilation in patients with obstructive sleep apnea?].

The pathogenesis of obesity hypoventilation is incompletely understood. We investigated 505 patients with sleep apnoea in respect of determinants that correlate with chronic hypercapnia. 14 patients (2.8 per cent) exhibited daytime hypercapnia (PCO2 greater than or equal to 45 mmHg). Compared with the entire group of patients, these patients showed heavier overweight (p less than 0.001) and their nightly respiratory dysregulation defined by the apnoea index was more severe (p less than 0.001). If these patients were compared with 14 normocapnic controls matched for apnoea index, weight and age, there was no difference in respect of lung function data. We conclude that overweight and the severity of sleep apnoea are determinants that predispose to chronic alveolar hypoventilation.

Adult↗

[Persulfate asthma in hairdressers].

At the a two-year apprenticeship, a young female hairdresser developed rhinoconjunctivitis and bronchial asthma, induced by a hair bleach containing the substance persulphate. On each occasion, her symptoms occurred in the form of an immediate reaction. The causative role of the bleach was demonstrated with the aid of an inhalation challenge test. In addition, the prick test produced a positive reaction vis-a-vis persulphate. The long latency period and the positive prick test might militate in favour of an allergic pathomechanism.

Adolescent↗

Decreased dipalmitoyllecithin content found in lung specimens from patients with so-called shock-lung.

Lung specimens were obtained from 9 patients with shock lung (adult respiratory distress syndrome), immediately after death, and from 8 controls. They were analysed for phospholipid content anf for fatty acid composition of sphingomyelin and lecithin. We found an elevated phospholipid content in the affected lungs but a decreased dipalmitoyllecithin fraction of total lecithin as indicated by 127% elevated content of oleic acid in lecithin. As a consequence the relation between the palmitic acid and oleic acid moiety of lecithin shifted from 2.32 in the normal lungs to 1.64 in the diseased lungs. Since the content of dipalmitoyllecithin is closely related to the function of the surfactant system we conclude, that the alteration of surfactant function, observed in patients with adult respiratory distress syndrome may be at least in part a result of an altered surfactant metabolism, but we cannot rule out, that the findings represent an epiphenomenon in shock lung.

Adult↗

[Behavior of serum IgE in patients with atopic extrinisic asthma. Studies with a modified radioimmunologic sorbent technic, Phadebas-IgEtest].

Serum IgE levels were measured by radioimmunosorbent techniqueera from patients with atopic extrinsic asthma, from patients with chronic bronchitis and from healthy adults. 51 of 65 patients with atopic extrinsic asthma had IgE values above the mean normal. Patients who were hypersensitive to different allergens commonly showed higher IgE concentrations than those who were hypersensitive to a single allergen only. Compared with IgE values found in patients with chronic bronchitis the differences were statistically highly significant. However the measurement of serum IgE may be a valuable diagnostic tool but only in supplement to other clinical investigations.

Adsorption↗