Biomedical subjects

K Philipson

Publications and source records attributed to K Philipson.

9 recordsLinked to original sources

PubMed1979

Elimination of test particles from the human tracheobronchial tract by voluntary coughing.

The effect of coughing on the elimination of inhaled 6 micrometer radioactively tagged teflon particles in humans was studied by external measurements of the radioactivity retained in the lungs before and after 1--2 min of voluntary coughing. In six healthy subjects coughing produced no substantial elimination of the particles. Six out of eight patients with lung disease produced expectorate and also eliminated particles from the lungs by coughing. The other two patients had no phlegm, did not produce any expectorate and did not eliminate particles by coughing. An increased amount of tracheobronchial secretion thus seems to be necessary for coughing to be effective. In the patients, the elimination of particles by coughing was fairly reproducible, suggesting that the test model may be useful for investigation of the influence of physiological and pharmacological factors on the elimination process.

Adult↗

PubMed1978

Tracheobronchial clearance 5-15 months after infection with Mycoplasma pneumoniae.

Tracheobronchial clearance was studied in 17 non-smokers who had suffered from a serologically verified Mycoplasma pneumoniae pneumonia 5-15 months earlier. The subjects inhaled 6 micron teflon particles tagged with 99mTc. The retention of the particles in the lungs was measured for 2 h. The retention after 2 h in this group was significantly higher than in a control group of healthy non-smokers. The results suggest that some impairment persists 5-15 months after the infection or that persons with slow clearance contract a mycoplasma pneumonia more easily than do those with fast clearance.

Adolescent↗

PubMed1978

Tracheobronchial clearance in patients with emphysema associated with alpha1-antitrypsin deficiency.

Tracheobronchial clearance was studied in five patients who had emphysema associated with deficiency of serum alpha1-antitrypsin but no history of chronic bronchitis. After the patients had inhaled an aerosol of 6 micrometer teflon particles tagged with 99mTc, the radioactivity in the lungs was followed externally during 2 h. Clearance in the emphysematous patients was normal or even rapid as compared with clearance in healthy subjects, and was significantly more rapid than clearance in patients with a history of chronic bronchitis. The results indicate that emphysema can develop in patients with alpha1-antitrypsin deficiency without their having an impairment of mucociliary transport.

Aged↗

PubMed1978

Cystic fibrosis compared with the immotile-cilia syndrome. A study of mucociliary clearance, ciliary ultrastructure, clinical picture and ventilatory function.

Patients with cystic fibrosis (CF) were investigated for mucociliary clearance (with and without stimulation by terbutaline), clinical picture, ventilatory function and ultrastructure of cilia. The results were compared with those of patients with congenitally immotile cilia (immotile-cilia syndrome). Mucociliary clearance could be demonstrated in all the seven CF patients who succeeded in inhaling the test aerosol. Ciliary ultrastructure from a deceased CF patient was normal. Patients with the immotile cilia syndrome had no substantial clearance and defective cilia. The CF patients coughed more during the clearance measurements than any other group studied earlier, and their coughing was effective. One patient succeeded in avoiding coughing in both measurements and had faster clearance when he got terbutaline than when he got the vehicle. Although younger, the CF patients tended to be more obstructed in their lungs and more handicapped than the patients suffering from the immotile-cilia syndrome. The latter patients had more discomfort from rhinitis, sinusitis and otitis than had the CF patients. An impairment of the mucociliary transport rate is hence unlikely to be a primary pathogenic factor for the respiratory tract disease in CF patients.

Adult↗

PubMed1976

Tracheobronchial clearance and beta-adrenoceptor stimulation in patients with chronic bronchitis.

The effect of a beta-adrenoceptor stimulating agent, terbutaline, on mucociliary transport in the lungs was studied in 10 patients with chronic bronchitis. Mucociliary transport was studied by having the patients inhale 6mum teflon particles tagged with 99mTc and by external measurement of the radioactivity in the lungs in the supine position. Terbutaline 0.25 mg and vehicle respectively were given subcutaneously in a cross-over double-blind study. On the average, clearance was slow in the examinations where the patients were given vehicle. Terbutaline produced a marked increase in mucociliary transport in four patients, a smaller increase in one and no effect in the others. Three out of the four patients who showed a marked inrease in clearance had less ventilatory impairment than the other seven patients. This may indicate that the mucociliary transport mechanism is less severely damaged in relatively early stages of the disease than in later stages. On the average FEV1.0 deteriorated significantly during the clearance measurements when vehicle was given, but did not change significantly when terbutaline was given.

Adult↗

PubMed1976

Tracheobronchial clearance in bronchial asthma: response to beta-adrenoceptor stimulation.

Tracheobronchial clearance was studied in 12 patients with bronchial asthma. They inhaled a test aerosol of 6 mum teflon particles tagged with 99mTc, after which external measurement of the radioactivity in the lungs was made for 2 h in the supine position. Clearance was determined after subcutaneous administration of 0.25 mg of the beta-adrenoceptor stimulating compound terbutaline and vehicle, respectively, in a crossover, double-blind study. The average clearance in the asthmatics did not differ significantly from that of healthy non-smokers. Terbutaline significantly enhanced clearance in the asthmatics, though considerably less than reported for healthy subjects. Alternative explanations for this weak effect of terbutaline in the asthmatics might be that the mucociliary transport system was affected by the asthma disease, or that earlier treatment with beta-adrenoceptor stimulating compounds or other drugs had produced increased tolerance and/or carry-over effects. Ventilatory function measured as FEV1.0 deteriorated significantly during the clearance measurement when vehicle was given, but not when terbutaline was given. Terbutaline thus counteracted the unfavourable effect of the supine position on ventilation.

Adult↗

PubMedDate not supplied

Increased mucociliary transport by adrenergic stimulation.

Tracheobronchial clearance of inhaled 6mum Teflon particles (density 2 gm/cu cm) tagged with technetium 99m was studied in healthy subjects by external measurement of the radioactivity in the lungs for two hours. Clearance, salivary secretion, blood pressure, and heart rate were determined in eight subjects after double-blind, subcutaneous administration of 0.25 mg terbutaline sulfate, a beta-adrenoceptor stimulating compound and vehicle, respectively, in a crossover study. Terbutaline produced a marked increase in clearance and a slight increase in heart rate, but had no important effect on salivary secretion or blood pressure. The result indicates that the blood concentrations of catecholamines might be of importance for the regulation of the mucociliary transport rate.

Adrenergic beta-Agonists↗

PubMedDate not supplied

Lung clearance of 4-micron particles coated with silver, carbon, or beryllium.

Lung clearance in rabbits during the first week after inhalation of 4-micron teflon particles tagged with chromium-51 and coated with silver, carbon, or beryllium was studied by external measurements of the radioactivity in the lungs. Ten rabbits were exposed to silver- and carbon-coated particles on two separate occasions within 3 weeks. Clearances of the two types of particles were quite similar. Clearance in eight other rabbits that had inhaled silver-coated particles was quite similar to clearance in eight rabbits that had inhaled beryllium-coated particles. The result is regarded as evidence that alveolar macrophages do not play an active role in removing intact particles from the lung the first week after inhalation.

Animals↗

PubMedDate not supplied

Human alveolar deposition of 4 micron teflon particles.

On two occasions ten healthy men inhaled with maximally deep inhalations at 0.5 1/sec a test aerosol of 4 micron teflon particles tagged with 111In. Radioactivity in the lungs was measured a few min, 24 hr, and 2, 3, and 4 days after inhalation. Retention decreased greatly between the measurements performed a few min and 24 hr after inhalation, but was similar in measurements 1 to 4 days after inhalation. Among individuals, retention varied considerably 1 to 4 days after inhalation (by a factor of 2), but the retention in each individual subject was uniform. Measuring the retention of a radioactively tagged test aerosol 1 day after inhalation, and regarding this retention as alveolar deposition, might be of value in preventive measures against certain toxic dusts.

Adult↗