Nasal mucociliary transport: new evidence for a key role of ciliary beat frequency

Novel nasal formulation of xylometazoline with hyaluronic acid: In vitro ciliary beat frequency study

Acute viral rhinosinusitis (viral ARS), or commonly referred to as the "common cold", is caused by respiratory viruses that cause disruption of the airway epithelial barrier and mucociliary dysfunction. Treatment of ARS is mainly symptomatic, with xylometazoline, a direct-acting α-adrenoceptor agonist, commonly used as a nasal decongestant. Unfortunately, this treatment does not resolve the epithelial dysfunction observed in ARS, and its use might negatively impact the nasal mucosa causing issues such as dryness, stinging, burning, rebound congestion, as well as atrophy. In light of this, a novel nasal spray formulation containing both xylometazoline and hyaluronic acid (HA) was developed to provide a more effective and safer treatment for viral ARS. HA is a natural polysaccharide known to hydrate and moisturise the upper respiratory tract, maintain the integrity of the nasal mucosa, and promote mucociliary clearance and wound healing. To investigate the potential of this combination, this study was conducted using the nasal MucilAirTMin vitro model and high-speed phase-contrast microscopy to examine the effect of xylometazoline and HA on ciliary function by measuring ciliary beat frequency and their cytotoxicity by morphological, histological and ultrastructural analysis. This research is the first to assess the effects of a specific dose and molecular weight of HA as an active pharmaceutical ingredient in nasal spray formulations. The combination of a fast-acting decongestant and an additional active agent targeting nasal epithelial dysfunction has the potential to provide an improved, reliable and safe treatment for viral ARS, and may serve as the basis for future clinical studies.

Impact of Bepanthen® and dexpanthenol on human nasal ciliary beat frequency in vitro

BACKGROUND

Dexpanthenol-containing ointments/fluids are recommended to restore impaired nasal mucosa. To date, there are no data about the influence of dexpanthenol or formulations including dexpanthenol on ciliary beat frequency (CBF) of nasal epithelial cells.

METHODS

We tested the ciliary beat frequency of human nasal epithelial cells in RPMI 1640 cell solution using in vitro high-frequency video microscopy every 60 s over a period of 15 min (min). Bepanthen^® solution and dexpanthenol in two clinically relevant concentrations (1.67% and 3.33%) were added to the cells. Addition of sterile water served as control group. To get a better overview, the measurements after 1 min, 5 min and 15 min were combined.

RESULTS

The CBF in the control group (n = 17) after 15 min was 7.3 ± 2.6 Hz. In comparison, the CBF after 15 min was 1.8 ± 1.0 Hz in the 3.33% Bepanthen^® group (n = 17) and 3.2 ± 1.2 Hz in the 1.67% group, which was statistically significantly lower in both groups (p < 0.001). With regard to the dexpanthenol group (n = 17) a CBF of 6.0 ± 2.6 Hz with 3.33% and 6.1 ± 2.4 Hz with 1.67% dexpanthenol, was detected, which was again statistically significantly lower (p = 0.06) compared to the control group except CBF at 15 min with 1.57% (n = 17; p = 0.04). In general, the effect on CBF was less pronounced with dexpanthenol compared with Bepanthen^® with a statistically significant difference between the two formulations. The results were verified by calculating an analysis of variance (ANOVA).

CONCLUSIONS

Bepanthen^® as an ointment, solution or inhalation is commonly used in ENT for mucosal care. Our results have shown that both substances reduce CBF in clinically relevant concentrations, although the effect was more pronounced with Bepanthen^® compared to dexpanthenol solution, which could be related to additives or change of physical properties in the solution. Further research is needed to assess potential clinical relevance.

Pulmonological issues

Pediatric leukodystrophies are rare neurodegenerative diseases involving multiple systems. Each form has unique neurologic features but are characterized by encephalopathy with accompanying impairments evidenced in reflexes, muscle tone and movement control. Weakness of expiratory, inspiratory, and upper airway muscles may lead to impaired airway secretion clearance resulting in recurrent respiratory infections, dysphagia, sleep-disordered breathing, restrictive lung disease, and ultimately chronic respiratory insufficiency.

Nasal Irrigation Delivery in Three Post-FESS Models From a Squeeze-bottle Using CFD

Purpose

Nasal saline irrigation is highly recommended in patients following functional endoscopic sinus surgery (FESS) to aid the postoperative recovery. Post-FESS patients have significantly altered anatomy leading to markedly different flow dynamics from those found in pre-op or non-diseased airways, resulting in unknown flow dynamics.

Methods

This work investigated how the liquid stream disperses through altered nasal cavities following surgery using Computational Fluid Dynamics (CFD). A realistic squeeze profile was determined from physical experiments with a 27-year-old male using a squeeze bottle with load sensors. The administration technique involved a head tilt of 45-degrees forward to represent a head position over a sink. After the irrigation event that lasted 4.5 s, the simulation continued for an additional 1.5 s, with the head orientation returning to an upright position.

Results

The results demonstrated that a large maxillary sinus ostium on the right side allows saline penetration into this sinus. The increased volume of saline entering the maxillary sinus limits the saline volume available to the rest of the sinonasal cavity and reduces the surface coverage of the other paranasal sinuses. The average wall shear stress was higher on the right side than on the other side for two patients. The results also revealed that head position alters the sinuses’ saline residual, especially the frontal sinuses.

Conclusion

While greater access to sinuses is achieved through FESS surgery, patients without a nasal septum limits posterior sinus penetration due to the liquid crossing over to the contralateral cavity and exiting the nasal cavity early.

An Adverse Outcome Pathway for Decreased Lung Function Focusing on Mechanisms of Impaired Mucociliary Clearance Following Inhalation Exposure

Adverse outcome pathways (AOPs) help to organize available mechanistic information related to an adverse outcome into key events (KEs) spanning all organizational levels of a biological system(s). AOPs, therefore, aid in the biological understanding of a particular pathogenesis and also help with linking exposures to eventual toxic effects. In the regulatory context, knowledge of disease mechanisms can help design testing strategies using in vitro methods that can measure or predict KEs relevant to the biological effect of interest. The AOP described here evaluates the major processes known to be involved in regulating efficient mucociliary clearance (MCC) following exposures causing oxidative stress. MCC is a key aspect of the innate immune defense against airborne pathogens and inhaled chemicals and is governed by the concerted action of its functional components, the cilia and airway surface liquid (ASL). The AOP network described here consists of sequences of KEs that culminate in the modulation of ciliary beat frequency and ASL height as well as mucus viscosity and hence, impairment of MCC, which in turn leads to decreased lung function.

Results of a RCT assessing saline and xylitol nasal irrigation for CRS and fatigue in Gulf War illness

OBJECTIVE

To assess the efficacy of saline nasal irrigation (S-NI) and xylitol nasal irrigation (X-NI) for chronic rhinosinusitis in participants with Gulf War illness (GWI).

METHODS

This 26 week, 3-arm (1:1:1) randomized controlled trial examined veterans meeting criteria for GWI with moderate-to-severe chronic rhinosinusitis and fatigue symptoms. All participants received standard of care for chronic rhinosinusitis (CRS); additionally, S-NI or X-NI participants added twice-daily NI using 2% saline or 5% xylitol solutions. Outcomes included disease-specific quality of life (primary; sino-nasal outcome test [SNOT-20]; 0-100 points), overall quality of life (Short-Form 36), and fatigue (Multidimensional Fatigue Index). Outcome assessors were blind to allocation group. Intention-to-treat analysis used repeated measures modeling; statistical significance was evaluated at the two-sided α level of .05.

RESULTS

Randomization (N = 40) produced three similar groups regarding sex (male, 80%), age (53.8 ± 7.8 years), duration (19.8 ± 7.7 years), and illness severity (48.5 ± 12.7 SNOT-20 points). Age- and gender-adjusted between-group comparison showed that X-NI participants, compared with control, reported improved SNOT-20 scores at 8 weeks (13.5 points, 95% confidence interval [CI] -27.9 to 0.9) and at 26 weeks (15.4 points, 95% CI -30.1 to -0.6). S-NI participants improved by 13.4 points (95% CI -28.8, 2.1) at 26 weeks compared with control.The improvement in both NI groups approached minimal clinical important difference compared to control for the SNOT-20 in the general population. Secondary outcomes were not different between groups. Satisfaction in both irrigation groups was high.

CONCLUSIONS

This randomized controlled trial suggests that NI with saline or xylitol improves chronic sinus symptoms among participants with GWI with improvement scores similar to those in the general population.

LEVEL OF EVIDENCE

1b, individual randomized controlled trial.

In vivo and in vitro observation of nasal ciliary motion in a guinea pig model

IMPACT STATEMENT

Cilia play an important role in the airway defense mechanism. So far, studies on ciliary function have mainly been based on in vitro methods. Images of in vivo ciliary motion are very difficult to capture. In this study, we describe a novel approach to observe and analyze nasal ciliary motion in living animals with comparison to in vitro observation. Such images of ciliary motion from living animals have not been reported to date. The result of the study indicates that in vivo ciliary physiological function differs from ex vivo and in vitro conditions in many ways, such as the stability over time and response to temperature variation. This is a good foundation for further in vivo analysis of airway ciliary physiological function in animals as well as humans.

Pediatric neuromuscular disorders: Care considerations during the COVID-19 pandemic

COVID-19, the respiratory and frequently systemic disease caused by the novel SARS-COV-2 virus, was first recognized in December 2019 and quickly spread to become a pandemic and world-wide public health emergency over the subsequent 3-4 months. While COVID-19 has a very low morbidity rate across approximately 80% of the population, it has a high morbidity and mortality rate in the remaining 20% of the population.1 These numbers have put a significant strain on medical systems around the world. Patients with neuromuscular diseases such as those with Duchenne muscular dystrophy (DMD) and spinal muscular atrophy (SMA), tend to be more medically fragile and have higher health care needs than the general population. Respiratory insufficiency, cardiac disease, obesity, and immunocompromised status due to chronic steroid treatments in certain patient populations with neuromuscular conditions are specific risk factors for severe COVID-19 disease. In general, the pediatric population has shown to be less severely impacted with lower infection rates and lower morbidity and mortality rates than the adult population, however, as expected, children with underlying medical conditions are at higher risk of morbidity from COVID-19 than their peers.2 Many patients with neuromuscular disease also rely heavily on caregiver support through their lifetime and thus maintaining the health of their primary caregivers is also a significant consideration in the health and well-being of the patients. This paper will address routine and emergency medical care, rehabilitation services, and other considerations for the pediatric patient with a neuromuscular condition during the COVID-19 pandemic.

Nasal Irrigation as Treatment in Sinonasal Symptoms Relief: A Review of Its Efficacy and Clinical Applications

Nasal irrigations have been used for centuries without any scientific data to determine its efficacy. Despite their widespread use, much confusion exist about the mechanism of action, preparation, indications and therapeutic advantage of nasal irrigations. Anecdotal evidence and poorly controlled studies add to the confusion. Recent evidence provides strong scientific justification of the benefits and advantages of using nasal irrigations in sinonasal symptoms relief. The present review of the evidence based literature highlights its efficacy and clinical applications.

Sinus irrigation penetration after balloon sinuplasty vs functional endoscopic sinus surgery in a cadaveric model

BACKGROUND

Nasal irrigation is a cornerstone of treatment for chronic rhinosinusitis. The purpose of this study was to quantify irrigation penetration to the sinuses following balloon sinuplasty and functional endoscopic sinus surgery (FESS).

METHODS

Balloon sinuplasty followed by FESS was performed on 4 cadaver heads. Using a high-volume, high-flow bottle, each head was irrigated with fluorescein-dyed water prior to and following each procedure, and recorded by rigid endoscopy through trephinations. Three blinded, fellowship-trained rhinologists reviewed videos and scored the extent of staining (using an accepted scale of 0 to 3) for each site.

RESULTS

The mean score prior to any procedure was maxillary sinus 1.67, frontal sinus 1.29, and nasal cavity 1.71. After balloon sinuplasty the mean was maxillary 2.25, frontal 2.04, and nasal cavity 2.17. After FESS the mean was maxillary 2.75, frontal 2.08, and nasal cavity 2.63. There was a statistically significant increase for both maxillary (p = 0.005) and frontal sinuses (p = 0.006) following balloon sinuplasty. There was a statistically significant increase following FESS compared to balloon for the maxillary sinus (p = 0.003), but not the frontal sinus (p = 0.96). Interrater reliability was good, with Cronbach's alpha of 0.85.

CONCLUSION

Irrigation improved in all sinuses following balloon sinuplasty and FESS. There was further improvement to the maxillary sinus after FESS; however, there was no difference in irrigation to the frontal sinuses following FESS compared to balloon sinuplasty. Extended frontal sinus approaches such as the Modified Lothrop procedure should be considered if more extensive access for irrigation is required.

Effectiveness of nasal irrigation devices: a Thai multicentre survey

Background

Nasal irrigation is widely used as an adjunctive treatment for nasal diseases. There is little evidence regarding the efficacy of the devices used in this procedure. The objective of this survey was to evaluate the effectiveness of nasal irrigation devices based on the experiences of patients and physicians.

Methods

We conducted a multicentre survey study between November 2017 and October 2018. Physician and patient questionnaires were developed based on the available literature and expert opinion. The physician questionnaire was submitted to the Otolaryngology residents and staff of each centre and their network. The physicians were also asked to distribute the patient questionnaire to their patients.

Results

Information regarding 331 devices used by the patients was collected. The mean age of the patients was 45.46 ± 17.19 years (from 5 to 81). Roughly half were male, and half were female (48.6%: 51.4%). Among the high-pressure devices, we found that the high-pressure large-volume nasal irrigation devices yielded significantly higher symptom scores in seven of 12 domains (p < 0.05). Among the large-volume devices, we found that the large-volume high-pressure nasal irrigation devices received significantly higher symptom scores in 4 of 12 domains (p < 0.05). However, a higher proportion of patients using the large-volume high-pressure devices had retained fluid in the sinuses compared to those using large-volume low-pressure devices (p < 0.001).

Conclusions

This survey supports the regular use of nasal irrigation, particularly with large-volume high-pressure devices, as an effective treatment for nasal disease. It may be effective at clearing nasal secretion, improve nasal congestion, decrease post-nasal drip, improve sinus pain or headache, improve taste and smell, and improve sleep quality. It could be used by patients with good compliance and minimal side effects.

Particularities and Clinical Applicability of Saccharin Transit Time Test

Introduction  The importance of mucociliary clearance (MCC) for the respiratory system homeostasis is clear. Therefore, evaluating this defense mechanism is fundamental in scientific research and in the clinical practice of pulmonology and of associated areas. However, MCC evaluation has not been so usual due to the complexity of methods that use radiolabeled particles. Nevertheless, as an interesting alternative, there is the saccharin transit time (STT) test. This method is reproducible, simple to perform, noninvasive, does not demand high costs, and has been widely used in studies of nasal MCC. Although the STT test is widely used, there is still lack of a detailed description of its realization. Objective  The present literature review aims to provide basic information related to the STT test and to present the findings of the previous studies that used this method, discussing variations in its execution, possible influences on the obtained results and limitations of the method, as well as to relate our experience with the use of STT in researches. Data Synthesis  There are several factors that can alter the results obtained from STT tests, which would raise difficulties with proper interpretation and with the discussion of the results among different studies. Conclusions  Saccharin transit time is a widely used method for the evaluation of nasal MCC, and therefore, the standardization related to the previous and concurrent to test orientations, and also its execution, become essential to improve its accuracy, and allow comparisons among different studies.

Mucociliary transport as a link between chronic rhinosinusitis and trace element dysbalance

Chronis rhinosinusitis is considered as a widespread public health issue with a prevalence of 10%. The disease significantly reduces quality of life and increases the risk of cardiovascular diseases as well as certain forms of cancer. Alteration of mucociliary clearance frequently observed in the patients and plays a significant role in disease pathogenesis. Certain studies have demonstrated that patients with chronic rhinosinusitis are characterized by significant reduction of essential trace elements and toxic metal overload. However, the particular mechanisms of the role of trace element dysbalance in chronic rhinosinusitis are unclear. We hypothesize that exposure to toxic trace elements (arsenic, nickel, cadmium) damages ciliary mucosal epithelium thus affecting mucociliary transport. In turn, altered mucociliary transport results in reduced removal of the inhaled metal-containing particles from nasal mucosa leading to their absorption and further aggravation of toxicity. Essential trace elements (zinc, selenium) play a significant role in regulation of mucociliary transport and immunity, thus their deficiency (either dietary or due to antagonism with toxic metals) may be associated with impaired functions and increased toxic metal toxicity. Therefore, a vicious circle involving metal accumulation and toxicity, essential element deficiency, impairment of mucociliary transport and metal particle removal, resulting in further accumulation of metals and aggravation of toxic effects is formed. The present hypothesis is supported by the findings on the impact of trace elements especially zinc and arsenic on mucociliary clearance, the role of mucociliary transport in heavy metal particles elimination from the airways, trace element dysbalance in chronic rhinosinusitis, as well as toxic and essential metal antagonism. The data from hypothesis testing and its verification may be used for development of therapeutic approach for management of chronic rhinosinusitis. Particularly, the use of essential elements (zinc, selenium) may reduce toxic metal toxicity thus destroying the vicious circle of heavy metal exposure, toxicity, alteration of mucociliary clearance, and aggravation of chronic rhinosinusitis. Essential element supplementation may be considered as a tool for management of chronic refractory rhinosinusitis. In addition, analysis of essential and toxic trace element status may provide an additional diagnostic approach to risk assessment of chronic rhinosinusitis in highly polluted environments.

[Nasal irrigation: opportunities and disadvantages]

RELEVANCE

Despite the widespread use of nasal irrigation in routine medical practice and a significant list of salt solution for nasal irrigation on the pharmaceutical market, contradictions remain in understanding of process essence, when salt solution acts on the mucous membrane of nasal cavity and evaluation of their effectiveness.

AIM

analysis of current data of frequency, methods and efficiency of systematic nasal irrigation and effect of salt solution at the mucous membrane of nasal cavity.

RESULTS

In review the authors generalized and analyzed recent information about meaning of nasal irrigation for upper respiratory tract disease, about role of nasal mucus at maintaining homeostasis in nasal cavity and initial respiratory tract in general. Describes the data about effect of nasal irrigation on antinfectious protect of mucous membrane of nasal cavity.

Chinese Society of Allergy Guidelines for Diagnosis and Treatment of Allergic Rhinitis

Allergic rhinitis (AR) is a global health problem that causes major illnesses and disabilities worldwide. Epidemiologic studies have demonstrated that the prevalence of AR has increased progressively over the last few decades in more developed countries and currently affects up to 40% of the population worldwide. Likewise, a rising trend of AR has also been observed over the last 2-3 decades in developing countries including China, with the prevalence of AR varying widely in these countries. A survey of self-reported AR over a 6-year period in the general Chinese adult population reported that the standardized prevalence of adult AR increased from 11.1% in 2005 to 17.6% in 2011. An increasing number of Journal Articles and imporclinical trials on the epidemiology, pathophysiologic mechanisms, diagnosis, management and comorbidities of AR in Chinese subjects have been published in international peer-reviewed journals over the past 2 decades, and substantially added to our understanding of this disease as a global problem. Although guidelines for the diagnosis and treatment of AR in Chinese subjects have also been published, they have not been translated into English and therefore not generally accessible for reference to non-Chinese speaking international medical communities. Moreover, methods for the diagnosis and treatment of AR in China have not been standardized entirely and some patients are still treated according to regional preferences. Thus, the present guidelines have been developed by the Chinese Society of Allergy to be accessible to both national and international medical communities involved in the management of AR patients. These guidelines have been prepared in line with existing international guidelines to provide evidence-based recommendations for the diagnosis and management of AR in China.

Regional Analysis of Sinonasal Ciliary Beat Frequency

Background

Mucociliary clearance, a primary host defense mechanism, depends on mucus production and its clearance by the coordinated beating of cilia lining the airways. Numerous investigations have analyzed ciliary activity in brushings from the inferior turbinate. To date, only one study has investigated whether there exists variation in ciliary beat frequency (CBF) within the sinonasal cavity. We analyzed CBF from the inferior turbinate, uncinate process, and sphenoethmoid recess in nonsinusitis patients to determine regional variability of ciliary activity within the sinonasal cavity.

Methods

Explants of sinonasal epithelium were analyzed at 37°C. Beating cilia were visualized with differential interference contrast microscopy. Images were captured using a high-speed digital camera with a sampling rate of 250 frames per second. A one-dimensional tracking algorithm analyzed individual pixel grayscale values within each frame of the video. The differences in grayscale were plotted as a time-dependent waveform, and frequency was calculated as the inverse of the peak-to-peak distance. A minimum of three areas of beating cilia were analyzed per regional sample. Statistical analysis was performed with repeated-measures analysis of variance.

Results

Complete sampling of all three sites was accomplished in 10 patients. No difference in CBF within the sinonasal cavity was identified (p < 0.05). The mean CBF for all sites in all patients was 12.6 ± 2.9 Hz, in agreement with published values.

Conclusion

This study shows no regional differences in CBF within the sinonasal cavity, supporting previous work and validating analysis of inferior turbinate cilia.

Early Effect of Exogenous Na Hyaluronate on Mucociliary Clearance

Background

An animal study is performed to determine the early effect of 1% Na hyaluronate on mucociliary clearance function.

Methods

One percent of Na hyaluronate was introduced into the maxillary sinuses of rabbits by anterior antrostomy. A physiological solution of 1% NaCl was introduced into the maxillary sinuses of a control group to equalize the influence of Na for both groups. The treatment material was sprayed with an atomizer for coating the maxillary sinus lining. Technetium-99m diethylenetriamine pentaacetate dynamic scintigraphic imaging was performed to evaluate mucociliary clearance function on all rabbits 72 hours after the surgical procedure.

Results

Although the mean rate of mucociliary clearance of the Na hyaluronate group was slightly worse than the control group; there was no statistically significant difference between them.

Conclusion

There is no early effect of exogenous 1% Na hyaluronate on mucociliary clearance function.

[About the safety of application of nasal decongestants in the practice of pediatricians]

Undesirable effects of the application of the intransal vasoconstricting medications are a frequent occurrence in the pediatric practice. The objective of the present study was to evaluate the role of the intranasal vasoconstricting medications in the structure of the means and methods currently available for the treatment of toxicological pathologies based at a multi-field clinical hospital. The retrospective analysis of the medical histories of the patients admitted to the toxicological department and annual reports for the period from 2015 to 2016 was undertaken. The study has demonstrated that intoxication associated with the use of the intranasal vasoconstricting medications was the most common cause of hospitalization of the children in the toxicological departments. Intoxication of this origin accounted for 15-20% of the total number of toxicological pathologies among the children. The cases of intoxication are most frequently documented in the group of children at the age between 1 and 3 years. The risk of the undesirable serious complications is especially high after the application of naphazoline-based intranasal vasoconstricting medications (71.7-77.4% of all the cases of intoxication with these products). It is concluded that the use of intranasal vasoconstricting medications in the pediatric practice should be carried out under the strict control, with the naphazoline-based preparations being totally excluded from the application.

Nasal care in intensive care unit patients

PURPOSE

The aim of this study was to investigate nasal hygiene in intensive care patients and improve patient care using isotonic saline nasal spray.

MATERIAL AND METHODS

In the study group, over a period of tendays saline nasal spray was administered four times daily. Nasal treatment was not given to the control group. Each patient was examined with a flexible nasopharyngoscope before and after the treatment and a nasal culture was taken.

RESULTS

In the study group, the secretion score (1- absent; 2- serosal; 3- seropurulent and 4- purulent) mean value improved from 1.9 to 1.4. In the control group, the secretion score mean value had risen from 1.7 to 3.1. At the beginning of the study, there was no difference in secretion scores between the groups, but on the tenth day a statistically significant difference was found.

CONCLUSION

The use of saline nasal spray in this group of intensive care patients was found to be effective in achieving nasal hygiene.

Pulmonary Toxicity of Benzalkonium Chloride

The available toxicity data of benzalkonium chloride (BKC) clearly shows that it is toxic; however, the weight of evidence favors the view that at doses encountered in nasally and orally inhaled pharmaceutical preparations it is well tolerated. The adverse toxicological data predominantly come from in vitro and animal studies in which doses and exposure periods employed were excessive in relation to the clinical doses and their posology and, therefore, not directly applicable to the clinic. The conflict between the in vitro and animal data and the clinical experience can be reconciled by understanding some of the physicochemical properties of BKC, the nasal and respiratory tract microenvironments, the doses used, and the posology.

Model identifies causes of nasal drying during pressurised breathing

Patients nasally breathing pressurised air frequently experience symptoms suggestive of upper airway drying. While supplementary humidification is often used for symptom relief, the cause(s) of nasal drying symptoms remains speculative. Recent investigations have found augmented air pressure affects airway surface liquid (ASL) supply and inter-nasal airflow apportionment. However the influence these two factors have on ASL hydration is unknown. The purpose of this study is to determine how ASL supply and airflow apportionment affect ASL hydration status for both ambient and pressurised air breathing conditions. This is done by modifying and adapting a nasal air-conditioning and ASL supply model. Model predictions of change in inter-nasal airflow apportionment closely follow in-vivo results and demonstrate for the first time abnormal ASL dehydration occurring during augmented pressure breathing. This work quantitatively establishes why patients nasal breathing pressurised air frequently report adverse airway drying symptoms. The findings from this investigation demonstrate that both nasal airways simultaneously experience severe ASL dehydration during pressurised breathing.

Airway Epithelial Cell Cilia and Obstructive Lung Disease

Airway epithelium is the first line of defense against exposure of the airway and lung to various inflammatory stimuli. Ciliary beating of airway epithelial cells constitutes an important part of the mucociliary transport apparatus. To be effective in transporting secretions out of the lung, the mucociliary transport apparatus must exhibit a cohesive beating of all ciliated epithelial cells that line the upper and lower respiratory tract. Cilia function can be modulated by exposures to endogenous and exogenous factors and by the viscosity of the mucus lining the epithelium. Cilia function is impaired in lung diseases such as COPD and asthma, and pharmacologic agents can modulate cilia function and mucus viscosity. Cilia beating is reduced in COPD, however, more research is needed to determine the structural-functional regulation of ciliary beating via all signaling pathways and how this might relate to the initiation or progression of obstructive lung diseases. Additionally, genotypes and how these can influence phenotypes and epithelial cell cilia function and structure should be taken into consideration in future investigations.

Radioactive Merano SPA Treatment for Allergic Rhinitis Therapy

Allergic rhinitis is a common nasal disorder with a high impact on quality of life, high social costs in therapies, and a natural development towards asthma. Pharmacological therapy is based on several genres of medications, of which intranasal corticosteroids are currently the most widespread. Thermal water treatment has traditionally been used as adjunctive treatment for chronic rhinitis and sinusitis. The present study was carried out to assess the clinical efficacy of nasal inhalation of radioactive oligomineral water vapours from the Merano hot spring and to compare it with the clinical efficacy of mometasone furoate nasal spray. A comparative prospective study was performed in 90 allergic patients treated at Merano hot springs: a group of 54 subjects treated with radioactive thermal oligomineral water and a control group of 36 subjects treated with mometasone nasal spray. Patients of both groups were assessed before and after treatment by Sino-Nasal Outcome Test questionnaire, active anterior rhinomanometry with flow and resistance monitoring, measurement of mucociliary transport time, and cytological examination of nasal brushing/scraping. The study showed that inhalation treatment with radioactive hydrofluoric thermal water for two weeks produces an objective clinical and cytological improvement in allergic patients, similar to that obtained with mometasone furoate nasal spray.

Model demonstrates functional purpose of the nasal cycle

Background

Despite the occurrence of the nasal cycle being well documented, the functional purpose of this phenomenon is not well understood. This investigation seeks to better understand the physiological objective of the nasal cycle in terms of airway health through the use of a computational nasal air-conditioning model.

Method

A new state-variable heat and water mass transfer model is developed to predict airway surface liquid (ASL) hydration status within each nasal airway. Nasal geometry, based on in-vivo magnetic resonance imaging (MRI) data is used to apportion inter-nasal air flow.

Results

The results demonstrate that the airway conducting the majority of the airflow also experiences a degree of ASL dehydration, as a consequence of undertaking the bulk of the heat and water mass transfer duties. In contrast, the reduced air conditioning demand within the other airway allows its ASL layer to remain sufficiently hydrated so as to support continuous mucociliary clearance.

Conclusions

It is quantitatively demonstrated in this work how the nasal cycle enables the upper airway to accommodate the contrasting roles of air conditioning and the removal of entrapped contaminants through fluctuation in airflow partitioning between each airway.

Combined inhaled salbutamol and mannitol therapy for mucus hyper-secretion in pulmonary diseases

This study focuses on the co-engineering of salbutamol sulphate (SS), a common bronchodilator, and mannitol (MA), a mucolytic, as a potential combination therapy for mucus hypersecretion. This combination was chosen to have a synergic effect on the airways: the SS will act on the β2-receptor for relaxation of smooth muscle and enhancement of ciliary beat frequency, whilst mannitol will improve the fluidity of mucus, consequently enhancing its clearance from the lung. A series of co-spray-dried samples, containing therapeutically relevant doses of SS and MA, were prepared. The physico-chemical characteristics of the formulations were evaluated in terms of size distribution, morphology, thermal and moisture response and aerosol performance. Additionally, the formulations were evaluated for their effects on cell viability and transport across air interface Calu-3 bronchial epithelial cells, contractibility effects on bronchial smooth muscle cells and cilia beat activity using ciliated nasal epithelial cells in vitro. The formulations demonstrated size distributions and aerosol performance suitable for inhalation therapy. Transport studies revealed that the MA component of the formulation enhanced penetration of SS across the complex mucus layer and the lung epithelia cells. Furthermore, the formulation in the ratios of SS 10(-6) and MA 10(-3) M gave a significant increase in cilia beat frequency whilst simultaneously preventing smooth muscle contraction associated with mannitol administration. These studies have established that co-spray dried combination formulations of MA and SS can be successfully prepared with limited toxicity, good aerosol performance and the ability to increase ciliary beat frequency for improving the mucociliary clearance in patients suffering from hyper-secretory diseases, whilst simultaneously acting on the underlying smooth muscle.

In vitro evaluation of the ciliary beat frequency of the rat nasal epithelium using a high-speed digital imaging system

Mucociliary clearance (MC) is an important factor in determining nasal drug absorption and the ciliary beat of ciliated epithelial cells of the nasal mucosa is the driving force of MC. However, the relationship between MC and ciliary beat frequency (CBF) is still ambiguous. The purpose of this study was to establish an evaluation method of CBF as an index of mucociliary function and examine the relationship between MC and CBF. A sequence of images of ciliary beating of an excised rat nasal septum was captured using a high-speed digital video camera. CBF (beats per second, Hz) was determined from periodic changes in the contrast value of a specific location in a sequence of images. CBF under control conditions was 8.49±0.38 Hz, which is similar to values reported for cultured human nasal epithelial cells and rat tracheal cells. β-Adrenergic and cholinergic antagonists decreased CBF, while β-adrenergic agonists and acetylcholine increased CBF. These results were similar with those observed for MC in our previous study. It was found that CBFs were significantly and linearly correlated with MC, indicating that MC is directly regulated by CBF and that this evaluation system allows the quantitative determination of nasal mucociliary function.

Tap water nasal irrigation in adults with seasonal allergic rhinitis: a randomized double-blind study

Saline nasal irrigation is effective in the treatment of seasonal allergic rhinitis, and sodium chloride itself has no antiallergic effects. The mechanism of saline nasal irrigation depends mainly on washing away allergens and inflammatory mediators induced by allergic reactions. Tap water has the same washing effects as saline. In this study, it was investigated if tap water nasal irrigation was effective in the treatment of seasonal allergic rhinitis. Sixty-four patients diagnosed with seasonal allergic rhinitis were enrolled. Patients were randomized to tap water nasal irrigation group and non-tap water nasal irrigation group for treatment. Patients of both groups were treated with desloratadine. Treatment outcomes were measured using allergic rhinitis Quality of Life (QoL) survey was completed at baseline and after 3 weeks of therapy. There were statistically significant differences in QoL scores between tap water nasal irrigation group and non-tap water nasal irrigation group. The tap water nasal irrigation group had better QoL scores than the non-tap water nasal irrigation group. Tap water nasal irrigation can be a valuable adjuvant therapy for patients with seasonal allergic rhinitis.

Efficacy of nasal irrigation in the treatment of acute sinusitis in atopic children

BACKGROUND

Nasal irrigation has been used as adjunctive therapy for sinonasal disease but is under-researched in children. The study aim was to evaluate the effectiveness of nasal irrigation with normal saline in the management of acute sinusitis in atopic children.

METHODS

We enrolled 60 atopic children with acute sinusitis, of whom 29 received nasal irrigation with normal saline and 31 did not receive nasal irrigation. All participants underwent a nasal peak expiratory flow rate (nPEFR) test, a nasal smear examination, and radiography (Water's projection) and were requested to complete a Pediatric Rhinoconjunctivitis Quality-of-Life Questionnaire (PRQLQ) during the baseline visit. All participants were requested to record symptoms in a daily diary and were followed up at 1-week intervals. A physical examination, nasal smear, and nPEFR were performed at each visit, and all daily diaries were collected. At the final visit (after 3 weeks), the symptom diaries were reviewed and participants were requested to complete the PRQLQ again. nPEFR, radiography, and a nasal smear were also repeated.

RESULTS

There were significant improvements in mean PRQLQ and nPEFR values (p < 0.05) for the irrigation compared to the non-irrigation group. There was no significant difference in radiographic findings between the groups (p > 0.05). The irrigation group recorded significant improvements in eye congestion, rhinorrhea, nasal itching, sneezing, and cough symptoms compared with the non-irrigation group.

CONCLUSION

Nasal irrigation is an effective adjunctive treatment for acute sinusitis in atopic children.

Correlation of nasal morphology to air-conditioning and clearance function

Nasal morphology plays an important functional role in the maintenance of upper airway health. Identification of functional regions, based on morphological attributes, assists in correlating location to primary purpose. The effects of morphological variation on heat and water mass transport in congested and patent nasal airways were investigated by examining nasal cross-sectional MRI images from 8 healthy subjects. This research confirms the previous identification of functional air-conditioning regions within the nose. The first is the anterior region where the morphology prevents over-stressing of tissue heat and fluid supply near the nares. The second is the mid region where low flow velocity favours olfaction and particle deposition. The third is the posterior region which demonstrates an increase in heat and water mass flux coefficients to compensate for rising air humidity and temperature. Factors identified within the congested airway that favour enhanced mucocillary clearance were also identified.

Effects of nitric oxide in mucociliary transport

The airways are made up of ciliated epithelium which secretes mucous, protecting the respiratory tract from particles inhaled during breathing. Its is paramount to understand the physiology and the mechanisms involved in mucociliary activity. Literature suggests that Nitric oxide (NO), especially the one produced by iNOS expression, maintains the mucociliary function and the immune defense of the nasal cavity.

Aim

to assess NO participation and the enzymatic pathways in the production of NO and mucociliary transport, using constructive and inductive NO synthetase inhibitors, L-NAME and aminoguanidine, respectively.

Materials and methods

frog palates were prepared and immerse in ringer (control), L-NAME or aminoguanidine solutions. The palates were immerse in these solutions for four periods of 15 minutes. Mucociliary transport measures were carried out before and after each exposure.

Results

control palates maintained stable their transportation speed. L-NAME increased, while aminoguanidine reduced mucous transportation velocity.

Conclusion

unspecific cNOS block with L-NAME and relatively specific iNOS block with aminoguanidine results leads us to propose that depending on the pathway, the NO can increase or reduce mucociliary transport in frog palates.

The effect of myrtol standardized on human nasal ciliary beat frequency and mucociliary transport time

BACKGROUND

This study was designed to observe the effects of myrtol standardized (Gelomyrtol forte), a secretomucolytic phytomedicine, on both ciliary beat frequency (CBF) in vitro and mucociliary transport time (MTT) in vivo.

METHODS

Changes in cultured human nasal CBF in response to immediate treatment with 75, 150, or 300 ng/mL of myrtol standardized and prolonged treatment (12 or 24 hours) with 300 ng/mL of myrtol standardized were quantified by using high-speed digital microscopy. In addition, MTT before and after oral application of myrtol standardized (three times a day, 900 mg/day, 10 days) was determined using the saccharine test, and the effects of this treatment regime on nasal patency was measured by acoustic rhinometry and active anterior rhinomanometry in 22 patients with nonallergic chronic rhinitis. Another 10 patients without medication, who had the same examinations twice with a 10-day interval, were involved as controls.

RESULTS

Neither immediate nor prolonged treatment with myrtol standardized produced a distinguishable change in CBF. Meanwhile, only in patients with treatment, MTT, as well as a unilateral minimum cross-sectional area, the volume of 0-5 cm inside the nasal cavity, the unilateral nasal resistance at 75 Pa and total symptom visual analog score were significantly improved after treatment.

CONCLUSION

Based on these results we propose that a 10-day treatment with an herbal medicine, myrtol standardized, improves nasal mucociliary clearance as well as nasal patency in patients with chronic rhinitis. However, it has no impact on ex vivo CBF.

Evaluation of the nasal mucociliary transport rate by rhinoscintigraphy before and after surgery in patients with deviated nasal septum

In this study, we have investigated the effect of nasal septal deviation (NSD) on nasal mucociliary activity and how does a septoplasty operation affecs the nasal mucociliary transport rate in the first and third months during the post-operative period. Twenty-two patients who were diagnosed with NSD and 22 healthy controls were studied using rhinoscintigraphy with Tc-99m-macroaggregated albumin (Tc-99m-MAA). On each case, the nasal mucociliary transport rate (NMTR) was measured pre-operatively only on five cases, on the first and third months of post-operative period. The NMTRs of patients with a deviated septum were significantly lower than the NMTRs of the healthy controls on both the convex and concave sides. Significant improvement was observed in the first post-operative month. On the concave and convex sides, the average postop third month post-operative NMTR value was higher than the first month post-operative NMTR values. It was concluded that the septoplasty operation improves reduced NMTRs after surgery. The effect of nasal surgery on nasal mucociliary activity may be more accurately evaluated in the third month than the first month of post-operative period.

The ciliary beat frequency of middle ear mucosa in children with chronic secretory otitis media

The chronic secretory otitis media (CSOM) is a common disease in children. Its cardinal symptoms are recurrent middle ear effusions and conductive hearing loss. Until today, the pathophysiological mechanism of this disease remains unknown. The correlation with adenoids and tubal dysfunction during childhood seems to be obvious, but the origin of middle ear effusions still has to be clarified. It is known that the CSOM affects the mucociliary system in several ways. In order to find out more about these correlations, the ciliary beat frequency was examined in 123 samples of infantile middle ear mucosa suffering from CSOM. Samples were surveyed using a stroboscopic microscopy method. The results of this study showed a significant decrease of ciliary beat frequency (CBF) to an average of 7.4 s(-1) in children with a CSOM. The healthy group of control showed a frequency of 10.1 s(-1). The measured CBF dataset was correlated with microbiological findings. We found a typical bacterial profile in nearly all the cases that were examined but were unable to find a specific bacterium decreasing CBF. This study provides evidence for the diminution of CBF in cases of CSOM in comparison to a healthy control group. Our findings emphasize the importance of stopping the vicious circle of recurrent effusions by paracentesis or grommet insertion.

Assessment of Upper Respiratory Tract and Ocular Irritative Effects of Volatile Chemicals in Humans

Accurate assessment of upper respiratory tract and ocular irritation is critical for identifying and remedying problems related to overexposure to volatile chemicals, as well as for establishing parameters of irritation useful for regulatory purposes. This article (a) describes the basic anatomy and physiology of the human upper respiratory tract and ocular mucosae, (b) discusses how airborne chemicals induce irritative sensations, and (c) reviews practical means employed for assessing such phenomena, including psychophysical (e.g., threshold and suprathreshold perceptual measures), physiological (e.g., cardiovascular responses), electrophysiological (e.g., event-related potentials), and imaging (e.g., magnetic resonance imaging) techniques. Although traditionally animal models have been used as the first step in assessing such irritation, they are not addressed here since (a) there are numerous reviews available on this topic and (b) many rodents and rabbits are obligate nose breathers whose nasal passages differ considerably from those of humans, potentially limiting generalization of animal-based data to humans. A major goal of this compendium is to inform the reader of procedures for assessing irritation in humans and to provide information of value in the continued interpretation and development of empirical databases upon which future reasoned regulatory health decisions can be made.

Influence of essential and fatty oils on ciliary beat frequency of human nasal epithelial cells

BACKGROUND

In alternative and complementary medicine, the use of essential and fatty oils has become more and more popular. In addition to conventional medical therapies, self-medication is showing increasing popularity, using agents with unclear compounds and poorly controlled dosages. Among other disorders, these alternative treatments are used in bronchitis and rhinitis, including some topical applications. Thus, the influence on ciliated epithelia should be evaluated, because a disturbance of the ciliary function can lead to recurrent sinusitis and chronic rhinosinusitis. The aim of this study was to test the influence of fatty and essential oils on the ciliary beat frequency (CBF) of nasal mucosa in vivo.

METHODS

The influence of sesame oil, soy oil, peanut oil, Miglyol 840, thyme oil, lavender oil, eucalyptus oil, and menthol on the ciliary activity of nasal brushings was evaluated by digital high-speed imaging.

RESULTS

The presence of most fatty oils resulted in an increase in CBF, the effect being highest for peanut oil. Miglyol 840 had no significant influence on CBF. The essential oils were tested at a concentration of 0.2 and 2%. Thyme oil did not affect CBF, whereas the presence of all other essentials oils resulted in an increase in CBF; the effect was higher at 0.2% than at 2%.

CONCLUSION

Except thyme oil and Miglyol 840, all tested oils caused an increase in CBF. Interestingly, the 0.2% concentrations of essential oils resulted in stronger effects when compared with the 2% concentrations.

Effect of oxymetazoline on healthy human nasal ciliary beat frequency measured with high-speed digital microscopy and mucociliary transport time

OBJECTIVES

We investigated the effects of oxymetazoline hydrochloride on the regulation of healthy human nasal ciliary beat frequency (CBF) and its influence on nasal mucociliary transport time (MTT).

METHODS

Changes in (cultured) human nasal CBF in response to increasing concentrations of oxymetazoline within 20 minutes were quantified by use of high-speed digital microscopy. Moreover, the MTT before and after application of 0.05% oxymetazoline was determined by use of the saccharin test.

RESULTS

Whereas no statistically significant difference was identified when compared to basal CBF at the concentration of 0.025% or 0.05%, both 0.10% and 0.20% oxymetazoline induced a significantly lower CBF at the end of the observation period. The decrement induced by 0.20% oxymetazoline appeared earlier. At concentrations ranging from 0.025% to 0.20%, the inhibitory effect was dependent on the concentration of oxymetazoline. In addition, the use of 0.05% oxymetazoline increased the mean (+/- SD) human nasal MTT from 474 +/- 21 seconds to 572 +/- 41 seconds (n = 29).

CONCLUSIONS

The clinical concentration of oxymetazoline, 0.05%, has no obvious inhibitory effect on human nasal CBF in vitro. The increased MTT caused by 0.05% oxymetazoline in vivo is within the normal range.

Topical treatment of rhinosinusitis

We reviewed current clinical evidence for the use of topical treatments in pediatric rhinosinusitis. Repeated Entrez PubMed searches were done using the template algorithm [rhinosinusitis AND (...)] with the settings: [Humans; English; All Child 0-18; Clinical trial; Last 10 yr] for the following comparators: steroid, irrigation, saline, antihistamine, decongestant, antibiotic, antimycotic, fungicide. The authors' clinical experience in the pediatric allergy unit of a university hospital was also drawn upon. Pediatric studies were retrieved but only one satisfied current evidence-based medicine standards for reporting clinical trials. Studies could not be systematized because of methodological, analytical, and interpretation biases. While saline irrigation, nasal decongestants, steroids, antibiotics, antihistamines and fungicides are all in widespread pediatric use, comparing studies from the literature for evidence of efficacy implied subjective appraisal, except in the case of topical steroids. Evidence for the efficacy of topical treatment for pediatric rhinosinusitis is narrative albeit this modality cannot be excluded from individualized patient protocols on the basis of the clinical literature alone. With the exception of topical steroids, no weighable evidence of effectiveness supports the premise that topical treatments actually serve the purpose for which they are widely prescribed in pediatrics.

The effect of endogenous nitric oxide on mechanical ciliostimulation of human nasal mucosa

BACKGROUND

Endogenous nitric oxide (NO) production by the inducible NO-synthase is enhanced in the nasal respiratory epithelium of patients with allergic rhinitis. Recent experimental data suggest endogenous NO to be strongly involved in the regulation of ciliary activity, the driving force of the mucociliary transport system.

OBJECTIVE

In this study, we investigated the effect of endogenous NO on mechanical stimulation of ciliary activity in a nasal mucosa explant model.

METHODS

Cultures of nasal mucosa explants were incubated with TNF-alpha and bacterial lipopolysaccharides (LPS) to enhance endogenous NO production. Direct in vitro NO imaging was performed by the fluorescent NO-indicator DAF-2 DA and laser scanning confocal microscopy. Ciliary beat frequency (CBF) was determined using a photoelectric technique. Mechanical stimulation was performed by two consecutive flow increments in a closed perfusion chamber. Endogenous NO-synthesis was blocked by l-NAME before the second flow stimulation.

RESULTS

Under control conditions the mean rise of CBF relative to baseline was 30.2% during the first flow increment and 30.7% during the second flow increment. Blocking of the endogenous NO synthesis in TNF-alpha/LPS-stimulated cultures reduced baseline CBF by 10.6+/-2.1% (P<0.05) but the effect of mechanical ciliostimulation on CBF remained unchanged (36.0% vs. 38.2%).

CONCLUSION

In conclusion, endogenous NO- and Ca(2+)-dependent mechanical stimulation of ciliary activity probably use independent intracellular signalling pathways. The combination of both effects on ciliary activity is likely to improve the local defence against inhaled allergens in patients with nasal allergies.

Techniques d’étude pharmacologique et clinique de l’obstruction nasale : application à la xylométazoline

Nasal obstruction, a prominent feature of rhinitis, may be quantified in humans by haemodynamic techniques (measuring local blood flux), static methods (measuring the geometry of nasal cavities) and dynamic methods (assessing the patency of nasal airways through the measure of resistance to air flow). These methods demonstrated the nasal decongestant activity of xylometazoline in healthy volunteers and rhinitis patients. Controlled double-blind studies established the clinical efficacy of xylometazoline in infectious and allergic (seasonal and perennial) rhinitis versus placebo and in comparison with various reference substances. The effects on nasal epithelium ciliary activity which are observed in vitro are modest and even less pronounced in vivo owing to dilution in situ and protective physiological processes.

Potential New Avenues of Treatment for Chronic Rhinosinusitis: an Anti-inflammatory Approach

Chronic rhinosinusitis is a complex disease process, one that is characterized by much more than just infection. Until its pathophysiology is understood fully, truly definitive therapy may remain elusive. As this underlying inflammatory process begins to unravel, however, new avenues of therapy will begin to emerge. This article discusses some of these new therapies and provides some clues as to where future avenues may go.

Sleep, breathing and the nose

During sleep there is a discrete fall in minute ventilation and an associated increase in upper airway resistance. In normal subjects, the nasal part of the upper airway contributes only little to the elevation of the total resistance, which is mainly the consequence of pharyngeal narrowing. Yet, swelling of the nasal mucosa due to congestion of the submucosal capacitance vessels may significantly affect nasal airflow. In many healthy subjects an alternating pattern of congestion and decongestion of the nasal passages is observed. Some individuals demonstrate congestion of the ipsilateral half of the nasal cavity when lying down on the side. Nasal diseases, including structural anomalies and various forms of rhinitis, tend to increase nasal resistance, which typically impairs breathing via the nasal route in recumbency and during sleep. A role of nasal obstruction in the pathogenesis of sleep-disordered breathing has been implicated by many authors. While it proves difficult to show a relationship between the degree of nasal obstruction and the number of disturbed breathing events, the presence of nasal obstruction will most likely have an impact on the severity of sleep-disordered breathing. Identification of nasal obstruction is important in the diagnostic work-up of patients suffering from snoring and sleep apnea.

Effect of topical nasal steroid sprays on nasal mucosa and ciliary function

PURPOSE OF REVIEW

This review was conducted to examine current evidence focusing on the effect of nasal steroid sprays on nasal ciliary function.

RECENT FINDINGS

Review of current literature suggests that long term effects of topical corticosteroid nasal sprays are safe and fail to cause damage to local nasal structure and function.

SUMMARY

The use of corticosteroid nasal sprays for the treatment of allergic rhinitis is widely accepted. Popularity of this class of medications is based on a well-established combination of efficacy, tolerability, and safety. Although current literature suggests that the use of intranasal steroids is indeed safe, increasing indications for prolonged administration continue to fuel debate regarding the long-term effect on local nasal structure and function. The purpose of this article is to review current literature addressing the effects of the components of local intranasal steroid sprays on the structure and function of the nasal mucosa.

A new approach to pharmacological effects on ciliary beat frequency in cell cultures--exemplary measurements under Pelargonium sidoides extract (EPs 7630)

The ciliary beat frequency (CBF) is an important parameter of the defence mechanism of the mucociliary system. We present a new method to determine pharmacological effects on CBF in vitro. Ciliated cell cultures of human nasal epithelium were obtained from partial resection of hyperplastic inferior turbinates in rhinosurgery. An adherent monolayer culture of ciliated cells was present after 10 days in vitro. This study exemplary examines, if a special extract from the roots of Pelargonium sidoides (EPs 7630) has an effect on the CBF in vitro. The influence of three concentrations of the extract (1, 30, 100 microg/ml) was tested. EPs 7630 significantly and concentration-dependently increased CBF to 123% at 30 microg/ml and to 133% at 100 microg/ml compared to the equilibration phase (100%). After rinsing with extract-free medium the CBF of cultured cells returned to nearly the normal range. In future, drug manipulation of the CBF by local application of rhinologics could be a new therapeutical concept in the treatment of upper airway diseases.

The effect of endogenous nitric oxide on cholinergic ciliary stimulation of human nasal mucosa

OBJECTIVES/HYPOTHESIS

Endogenous nitric oxide (NO) production by inducible nitric oxide synthase is enhanced in the nasal ciliated respiratory tract epithelium of patients with allergic rhinitis. Recent experimental data have suggested endogenous NO to be strongly involved in the complex regulation of ciliary activity, the driving force of the mucociliary transport system. The authors investigated the effect of endogenous NO on acetylcholine-stimulated ciliary activity of human nasal mucosa.

STUDY DESIGN

In vitro study.

METHODS

Cultures of human nasal mucosa explants were incubated with tumor necrosis factor-alpha and bacterial lipopolysaccharides to enhance endogenous NO production. Expression of inducible NO synthase was morphologically demonstrated by immunohistochemistry. Ciliary beat frequency was determined by phase-contrast microscopy of ciliated epithelium, using a computerized photoelectric technique. Stimulation experiments were performed in vitro with acetylcholine and N(G)-nitro-l-arginine methyl ester (L-NAME), a NO synthase inhibitor.

RESULTS

Upregulation of inducible NO synthase in the respiratory tract epithelium after stimulation with tumor necrosis factor-alpha and lipopolysaccharide was visualized by immunohistochemical analysis. Experimental inhibition of enhanced endogenous NO production by 10 mol/L L-NAME significantly reduced baseline ciliary beat frequency from 8.6 +/- 0.2 to 7.8 +/- 0.2 Hz (P < .05). Cholinergic ciliary stimulation above baseline by 10 mol/L acetylcholine was not significantly different before (11.5%) or after (10.8%) blocking of endogenous NO production.

CONCLUSION

Taken together, the study results suggest that baseline ciliary activity depends on endogenous NO production but that the extent of cholinergic ciliary stimulation is independent of endogenous NO production. The combination of the two effects may improve nasal mucociliary clearance of inhaled allergens in patients with allergic rhinitis.