The mucociliary activity of the upper respiratory tract. I. A method for use in experimental studies on human material

The effects of uncinectomy and natural ostial dilatation on maxillary sinus ventilation: a clinical experimental study

The purpose of this study was to determine the effect of uncinectomy without sinusotomy and natural ostial dilatation on maxillary sinus ventilation in chronic rhinosinusitis. Twenty patients with chronic rhinosinusitis were included in this study. The patients were randomly divided into two groups. Group 1 consisted of patients with uncinectomy (n = 10), while group 2 was made up of patients treated with natural ostial dilatation (n = 10). The CO(2) tension and pressure levels of the maxillary sinus during inspiration and expiration phases were obtained and compared before and after the procedures within and between the groups. The mean CO(2) tension levels in both groups were significantly decreased after the procedures. The mean maxillary sinus pressure during inspiration was significantly decreased to a negative value after uncinectomy; however, no significant change was observed during expiration. There were no significant changes in maxillary sinus pressures after natural ostial dilatation procedure. Both uncinectomy and natural ostial dilatation seem to be equally effective in decreasing maxillary sinus pCO(2) levels. The effects of decreased maxillary sinus pressure during inspiration after uncinectomy on mucociliary clearance and development mechanisms of chronic rhinosinusitis seem to be worth investigating.

Gaseous dynamics of the rabbit maxillary sinus

To better understand the mechanisms underlying maxillary sinus function, the gas composition of the sinus antrum in spontaneously breathing and tracheotomized rabbits (n = 17) was compared. The gas composition of samples (n = 117) obtained from rabbit maxillary sinuses was determined by gas chromatography. Results demonstrated significant differences (P < .005) in sinus gas composition between nasal breathing and tracheotomized animals for oxygen (02) and carbon dioxide (CO2). In tracheotomized animals O2 levels decreased while CO2 levels increased markedly to suprasystemic levels. This unexpected finding may be due to reduced sinus blood flow and the effects of nasal versus tracheal respiration. We conclude that the gaseous dynamics and perhaps the function of the maxillary sinus vary under different respiratory conditions. A better understanding of these processes may lead to earlier diagnosis and the development of improved treatments for sinus disease.

A device for measuring mucociliary activity in the human bronchi during fibre-optic bronchoscopy

An in vivo method for the study of mucociliary activity in the human trachea and bronchi is presented. The method is based on a two-way fibre-optic system whereby reflections of light emitted by one glass-fibre and reflected by the cilia are picked up by a second glass fibre and transmitted to a recording unit. The glass fibre system is designed to be used in conjunction with a regular fibre bronchoscope, and is convenient for routine use in daily clinical work. As reference material, 15 subjects aged 23-73 years without evidence of disease were examined in their right upper bronchus. The average cilial beat frequency was found to be 12.0 +/- 1.0 (SD) waves per second.

Ciliary beat of cultured human respiratory cells studied with differential interference microscope and high speed video system

The ciliary beating of upper respiratory tract cells cultured on cover glasses was studied by using differential interference microscope equipped with high speed video. By culturing the cells on collagen coated cover glasses, objectives with higher magnifications could be used. With this system we could evaluate not only ciliary beat frequency, but also amplitude, wave form, orientation and synchrony of ciliary beating. Also some structural anomalies such as compound cilia and tide cilia bundles could be recognized. Ciliary beat frequency measured from 1,026 ciliated cells was 20.6 +/- 4.7 Hz (mean +/- SD). The orientation of ciliary beat directions was random and the mean standard deviation for measured angles was 73.0 degrees +/- 28.9 degrees (mean SD +/- SD). When the ciliary beat frequency was 20 Hz, the time used for effective phase was 0.022 +/- 0.002 s (mean +/- SD), and 0.028 +/- 0.004 s (mean +/- SD) for the recovery phase of beat. This system is advantageous for studying ciliary function because all parts can be studied simultaneously with higher magnification, and the effects of chemical physical mediators can be studied without disturbing effects of the autonomic nervous system or secretory cells. Also, the same cells could be observed before and after challenge with test medication and thus evaluated more accurately.

Laser light scattering spectroscopy: a new method to measure tracheobronchial mucociliary activity

Laser light scattering spectroscopy is based on the evaluation of the frequency shift of coherent light scattered by moving particles. This makes it particularly suitable for use in light guiding systems. In this study laser light scattering spectroscopy was assessed for its ability to provide information on the motility of respiratory cilia. In vitro and in vivo measurements were undertaken with animal tracheal mucosa. The intensity fluctuations of laser light scattered from moving cilia were analysed in terms of their autocorrelation functions to provide information on the frequency and synchrony of beating cilia. In vitro measurements were performed on fresh bovine trachea to estimate a safe laser power level for mucosal exposure and to test the method by defining the temperature dependence of the ciliary beat frequency. Power densities not exceeding 0.3 kW/cm2 were found to be the upper limit for long term exposure of the mucosa in vitro. Ciliary beat frequency showed a pronounced temperature dependence, ranging from 5.8 to 28.3 Hz over the temperature range 20-43.5 degrees C. A maximum frequency was found at 41.5 degrees C. In vivo measurements of ciliary activity were performed in six pigs by means of optical fibres for light transmission combined with fibreoptic bronchoscopy. A ciliary beat frequency of 5 Hz was obtained; heart and breathing frequencies could be separated and identified. These results suggest that laser light scattering spectroscopy might provide a convenient method of studying the mucociliary system of the lower airways.

Effects of Staphylococcus aureus on the ciliary activity of the middle ear lining

Our previous investigation using normal guinea pigs disclosed that, like respiratory mucosa, the middle ear lining has ciliary activity, and that this ciliary activity becomes more active as the location becomes more distal to the eustachian tube. In this experimental study, the effects of Staphylococcus aureus on the middle ear lining was examined from functional and morphological viewpoints. In conclusion, the ciliary activity at the entrance to the eustachian tube and that more distal to the tube present a similar pattern of reaction to S aureus in an in vitro system. On the other hand, the ciliary activity of the middle ear lining displays a varying pattern of reaction according to the locations within the tympanic cavity.

The effect of carbon dioxide on the activity of cilia. A study on rabbit sinus mucosa in vitro

The relation of ciliary activity to the partial pressure of carbon dioxide was studied with a photoelectric method on rabbit sinus mucosa in vitro. A dose-response relationship was found, where by ciliary activity was impaired at pCO2 above 5 kPa. The effect of elevated partial pressure of carbon dioxide on ciliary activity in secretory otitis media and sinusitis is discussed.

Effects of neuropeptides on mucociliary activity

The effects of four neuropeptides, vasoactive intestinal polypeptide, enkephalin, bombesin, and substance P, on mucociliary activity in the rabbit maxillary sinus were investigated in vivo. The peptides were administered via the feeding artery (arteria maxillaris), and the resulting effects were registered with a noninvasive photoelectric technique. The peptides were tested in the dose range 0.0001 to 10 micrograms/kg body weight. The following results were observed: 1) vasoactive intestinal polypeptide and enkephalin did not influence mucociliary activity; 2) bombesin had only a slight accelerating effect on the mucociliary activity at doses of 0.1 to 10 micrograms/kg; and 3) substance P markedly accelerated the mucociliary activity in a dose-dependent manner in the dose range 0.01 to 10 micrograms/kg, the maximal increase being about 50%. The effect of substance P was atropine-resistant, and probably acted directly on the mucosa.

A versatile and quantitative computer-assisted photoelectronic technique used for the analysis of ciliary beat cycles

The beat cycles of rabbit tracheal cilia in culture and Mytilus laterofrontal cirri were recorded using a phototransistor, transillumination, video, and phase-contrast microscopy. The photoelectronic signal and video image of the ciliary activity were simultaneously recorded as a composite image. The photoelectronic signal was converted into a digital signal by a data acquisition system for further computer processing. By the selection of a small detector area and accurate detector alignment, a simple, repetitive photoelectronic signal representing ciliary activity was obtained. This signal records the ciliary beat frequency and demonstrates the triphasic nature of the beat cycle. The photoelectronic signal can be precisely correlated with the ciliary activity by analysis of the composite video recordings to provide the duration of the effective, recovery, and rest phases of the beat cycle. The video-photoelectronic signal correlations were verified by high-speed cinematography. High-speed films of ciliary activity were digitized, and the image density of selected pixels was analyzed by computer with respect to time and ciliary motion. These studies indicate that duration of the phases of the beat cycle are differentially reduced with increased beat frequency; the effective phase duration was quickly reduced to a minimum. This was followed by the reduction of the duration of the recovery phase to a minimum. The rest phase continues to be reduced without reaching a minimum, over the range of beat frequencies observed. These results suggest that ciliary beat frequency may be regulated either by modifying the rates of dynein-microtubule interactions or the rate of transition from one beat phase to the next.

Effects of penicillins in vitro on mucociliary activity of rabbit trachea

The effect of eight penicillins on the mucociliary activity of rabbit trachea was tested in vitro. Carbenicillin and ampicillin had a minor inhibitory effect. Penicillin G and V and pheneticillin were a little more ciliestatic. Propicillin, cloxacillin and dicloxacillin were most toxic. The mucociliary toxicity increased with increasing lipophilicity of the penicillins and correlated well with their known neurotoxic in vivo effects.

Effects of cystic fibrosis serum and cell culture medium on the mucociliary activity of the respiratory tract. An in vitro study in rabbits

As previously reported a cystic fibrosis factor (CFF) is associated with the dyskinetic ciliary motion induced by serum and cell culture medium from patients with cystic fibrosis (CF). In this study a sensitive, standardization method, for the photoelectric recording of mucociliary activity was used to examine the effect of sera and media from cell cultures taken from patients with CF and healthy controls, on the mucociliary activity of rabbit trachea in vitro. No signs of decreased mucociliary activity were observed and electron microscopy showed normal ultrastructure and orientation of cilia.

The mucociliary activity of the respiratory tract. I. Inhibitory effects of products of Pseudomonas aeruginosa on rabbit trachea in vitro

Bacteriological filtrates of three strains of Pseudomonas aeruginosa were compared with respect to inhibitory effect on ciliary movements and a quantitative difference was established between them. The cilia inhibitory effect was strictly concentration-dependent and was resistant to heating. The ciliotoxic effect disappeared from filtrates after chloroform extraction. The chloroform-extracted sediment ws dissolved in physiological saline and the solution revealed an inhibitory effect on cilia. Involvement of endotoxin is not probable, since E. coli endotoxin in a high concentration was not toxic. Partially purified Pseudomonas aeruginosa phenazine pigment as well as haemolysin inhibited ciliary activity and the effect was standardized in the present experimental system.

The mucociliary activity of the upper respiratory tract. II. A method for in vivo studies on maxillary sinus mucosa of animals and human beings

A method for photoelectric in vivo recordings of the mucociliary activity of the mucosa of the upper respiratory tract is described and tested in model experiments. In vivo recordings from the maxillary sinus mucosa of rabbits were easy to analyse and the method is useful for further experimental research on animals. Examples of in vivo recordings from the human maxillary sinus during Caldwell-Luc operations are also presented. These results are compared with subsequent in vitro recordings of biopsy material.