Patient-reported experience with hypoglossal nerve stimulation in the treatment of obstructive sleep apnea

BACKGROUND

Breathing-synchronized hypoglossal nerve stimulation (HNS) is routinely used as an alternative treatment for patients with obstructive sleep apnea (OSA). Significant and clinically relevant improvements in disease severity and OSA symptoms such as daytime sleepiness as well as overall quality of life have been reported in randomized-controlled trials and large real-world cohort studies. However, so far, few data exist on patient-reported experience with the treatment.

METHODS

A structured survey with 22 questions was constructed using five-level Likert scales (1 = no agreement, 5 = complete agreement) to evaluate patient experience with HNS and perception of the treatment in the domains "Overall experience with therapy," "Experience with treatment process," and "Side-effects from treatment." Additional data were collected on current symptom status, measured with Epworth sleepiness scale (ESS) questionnaire, and OSA disease history. Multiple linear regression analysis was conducted to test associations of medical variables and response behavior. Correlations between variables and domains, as well as individual items, were assessed using Spearman rank test.

RESULTS

A total of 75 patients from Germany who were treated with breathing-synchronized HNS were enrolled (mean age 57.3 years, 78% male), and 71 questionnaires with complete data were included for analysis. Two-thirds of participants (67%) had a history of OSA history for 5 years or longer. Of all patients, 76% had normalized OSA symptoms at time of the study (ESS: 6.4 ± 5.0) and 98% reported using stimulation therapy every night. Regression analysis revealed an association of current symptoms measured with ESS and response behavior. Hence, patients with normalized daytime sleepiness reported significantly more positive experience across all domains assessed, compared to patients with residual daytime sleepiness. Overall, only 2% of participants reported side effects that made them reduce or discontinue stimulation therapy. The rate of reported side effects was associated with current symptom control under therapy.

CONCLUSIONS

Overall patient-reported experience with breathing-synchronized HNS therapy was positive and high satisfaction with the treatment process was observed. Side effects occurred, but rarely affected subjective use of the therapy or satisfaction. Subjective experience and perception are influenced by residual daytime sleepiness with stimulation therapy.

Patient-reported outcomes with hypoglossal nerve stimulation for treatment of obstructive sleep apnea: a systematic review and meta-analysis

INTRODUCTION

Hypoglossal nerve stimulation (HNS) has recently been introduced as an alternative treatment for patients with OSA. A large number of studies have demonstrated substantial changes in OSA with this therapy by reducing respiratory events and improving symptoms such as daytime sleepiness and quality of life. The objective of this review was to conduct a systematic review and meta-analysis to evaluate patient-reported outcomes and experience with HNS therapy.

METHODS

A systematic literature search of MEDLINE, Cochrane, and Web of Science was performed to identify randomized controlled and observational studies reporting subjective outcomes with different HNS systems in patients with OSA. Abstracts of 406 articles were screened and a subset of 55 articles were reviewed for eligibility. Risk of bias was assessed using the ROBINS-I tool. Meta-analysis using RevMan was performed when > 2 studies were identified that reported data on a specific outcome.

RESULTS

Thirty-four publications reporting data on 3785 patients with a mean follow-up of 11.8 ± 12.2 months were identified and included in the meta-analysis. The analysis revealed a pooled effect of 4.59 points improvement in daytime sleepiness as measured by the ESS questionnaire (Z = 42.82, p < .001), 2.84 points improvement in daytime functioning as measured by the FOSQ score (Z = 28.38, p < .001), and 1.77 points improvement in sleep quality as measured by the PSQI questionnaire (Z = 2.53, p = .010). Patient-reported experience was consistently positive and revealed additional relevant aspects from this perspective.

CONCLUSION

HNS therapy significantly improves quality of life in patients with OSA and reliably produces clinically meaningful effects on daytime sleepiness, daytime functioning, and sleep quality. Treatment regularly meets or exceeds the minimum clinically important differences defined for the respective instruments. Additional research is needed to further investigate effects on quality of life beyond improvements in daytime sleepiness and daytime functioning.

Bilateral vs Unilateral Hypoglossal Nerve Stimulation in Patients With Obstructive Sleep Apnea

Objective

Unilateral hypoglossal nerve stimulation (uniHNS) is an effective treatment for obstructive sleep apnea. Bilateral hypoglossal nerve stimulation (biHNS) is a novel therapeutic option and a different approach to hypoglossal nerve stimulation. The aim of this study was to analyze the clinical outcome of the first 10 biHNS cases vs the first 10 uniHNS cases ever implanted.

Study Design

Prospective data analysis.

Setting

International multicenter comparative clinical trial.

Methods

The first 10 patients in 2020 who received a biHNS device (Genio System; Nyxoah) and the first 10 patients in 2014 who received a uniHNS system (Inspire II; Inspire Medical Systems) were included. Treatment outcome was evaluated at 3 months after surgery. Data collection included demographics, apnea hypopnea index (AHI), oxygen saturation and desaturation index, Epworth Sleepiness Scale, and adverse events.

Results

The mean ± SD age was 52.1 ± 9.6 years (biHNS) and 58.3 ± 8.6 years (uniHNS). The mean body mass index was 26.4 ± 5.6 kg/m² (biHNS) and 26.2 ± 2.2 kg/m² (uniHNS). The mean preimplantation AHI (biHNS, 39.9 ± 14.8/h; uniHNS, 32.2 ± 11.0/h) decreased in both groups after 3 months (biHNS, 19.2 ± 14.0/h, P = .008; uniHNS, 13.1 ± 16.8/h, P = .037) with no significant difference between groups (P = .720). The mean preimplantation Epworth Sleepiness Scale (biHNS, 11.8 ± 6.2; uniHNS, 11.1 ± 4.9) decreased as well after 3 months (biHNS, 9.4 ± 6.3; uniHNS, 6.0 ± 5.0).

Conclusion

Preliminary postmarket data suggest that biHNS may be as safe and effective as uniHNS. Long-term follow-up in a larger sample size is required to assess the stability of biHNS.

Sleep position, patient comfort, and technical performance with two established procedures for home sleep testing

Purpose

In patients with a high pre-test probability of suffering from obstructive sleep apnea (OSA), (cardio)-respiratory polygraphy (RP; level 3) is commonly used for home sleep testing (HST); however, testing based on peripheral arterial tonometry (PAT) is increasingly recognized as an alternative method. The aim of the study was to compare sleep position, patients’ comfort, and technical failure rates of HST with RP and PAT in patients with suspected OSA.

Methods

Sleep position, patients’ comfort, and technical failure rates of RP and PAT were compared in 56 patients receiving two nights of HST with either RP or PAT in a randomized fashion.

Results

Time in supine position with PAT was significantly lower (173.7±88 min) compared to RP (181.7±103.7 min; p < 0.001), although the absolute mean difference was not clinically significant. Patients reported to sleep better, feeling less disturbed when falling asleep, losing less sensors, and fewer nightly awakenings with PAT, but experienced more pain at the side of the finger probe. Forty-five out of 56 patients (80%) rated PAT as being the superior sleep test and 49 out of 56 (88%) would prefer PAT for further investigations (p<0.001). PAT testing was associated with less technical failures.

Conclusion

The results demonstrate that HST with PAT leads to less time in supine sleep positioning, which may be clinically relevant in selected patients. Moreover, PAT is associated with less technical failures and is perceived with less discomfort during testing and a reduced number of nocturnal awakenings in patient self-reports.

Cocaine Reduces Ciliary Beat Frequency of Human Nasal Epithelial Cells

BACKGROUND/AIM

Cocaine is a widely used recreational drug and is known for its nasal complications including epithelial, cartilage and bone damage. The aim of the study was to analyze the impact of cocaine on ciliary beat frequency (CBF) of human nasal epithelial cells and therefore better understand its side effects on nasal mucosa.

MATERIALS AND METHODS

Nasal epithelial cells of 21 healthy subjects were harvested and exposed in vitro to cocaine hydrochloride solutions ranging from 0.875% to 7%. High-speed video footage was acquired with phase contrast microscopy and CBF was analyzed with Sissons-Ammons Video Analysis (SAVA) software.

RESULTS

All tested concentrations led to a significant reduction in CBF compared to the control. Effects increased over time and with concentration. A mechanical inhibition of cilia by cocaine crystals was also observed.

CONCLUSION

We assume that CBF reduction is part of the pathomechanism leading to nasal complications in cocaine abuse. Considering these results, clinical usage of cocaine should be critically evaluated and restricted to select cases only.

Apoptosis-related Proteins Are Altered by Selective Tyrosine Kinase Inhibitors and Everolimus in HPV-dependent SCC

BACKGROUND

Head and neck squamous cell cancer (HNSCC) affects the oral cavity and the pharynx. The aim of the study was to investigate the effects of selective tyrosine kinase inhibitors (TKIs) erlotinib, gefitinib, nilotinib and dasatinib and the mammalian target of rapamycin (mTOR) inhibitor everolimus on the expression of apoptosis-related proteins caspase-3, FAS cluster of differentiation (CD)-95 and FAS ligand in human papilloma virus (HPV)-dependent squamous cancer.

MATERIALS AND METHODS

Two HPV-negative cell lines (UMSCC-11A/-14C) and one HPV-positive cell line (CERV196) were incubated with TKIs or everolimus and protein concentrations of target proteins were analyzed with enzyme-linked immunosorbent assay (ELISA).

RESULTS

Caspase-3 was affected by the tested TKIs in HPV-positive SCC, whereas FAS CD95 and FAS ligand were influenced in HPV-negative SCC.

DISCUSSION

This is the first study to analyze the influence of TKIs and everolimus on key proteins of apoptosis. Our results provide novel information contributing to a better understanding of the cell biology of HPV-dependent HNSCC and might contribute to the discovery of novel pharmaceutical treatment strategies for HNSCC.

Diagnosis and treatment of isolated snoring-open questions and areas for future research

STUDY OBJECTIVES

Snoring is a common phenomenon which is generated by vibration of soft tissue of the upper airway during sleep. Due to the high incidence of isolated snoring and the substantial burden for the patient and the bed partner, a thorough examination and appropriate therapy are required. Many recommendations for the treatment of isolated snoring are either not evidence-based or are derived from recommendations for the management of obstructive sleep apnea. Therefore, the aim of this study is the identification and description of open questions in the diagnosis and treatment of isolated snoring and the illustration of areas for further research.

METHODS

In the context of the development of the new version of the German guideline "Diagnosis and treatment of isolated snoring in adults," a multidisciplinary team of experts performed a systematic literature search on the relevant medical data and rated the current evidence regarding the key diagnostic and therapeutic measures for snoring.

RESULTS

The systematic literature review identified 2293 articles. As a major inclusion criterion, only studies on primary snoring based on objective sleep medical assessment were selected. After screening and evaluation, 33 full-text articles remained for further analysis. Based on these articles, open questions and areas for future research were identified for this review.

CONCLUSION

Several major gaps in the literature on the diagnosis and treatment of isolated snoring were identified. For the majority of diagnostic and therapeutic measures for snoring, high-level scientific evidence is still lacking.

Changes in breath cycle sensing affect outcomes in upper airway stimulation in sleep apnea

BACKGROUND

Upper Airway Stimulation (UAS) is a well-established therapy option for obstructive sleep apnea (OSA).

AIMS

There are no data on whether respiratory sensing contributes to successful UAS therapy.

MATERIALS & METHODS

After initial measurements of 3 implanted patients (M1), the sensing signal was inverted (M2) without changing other parameters. Two weeks later, the signal was converted back again, and the sensitivity of breathing cycle detection was turned to a very low state (M3).

RESULTS

At M2 and M3, the apnea-hypopnea index and oxygen desaturation index increased.

DISCUSSION

Correct respiratory sensing is important for controlling OSA using UAS.

CONCLUSIONS

Therefore, implant centers should should optimize respiratory sensing placement and adjustment.

Nondiffusive fluxes in a Brownian system with Lorentz force

The Fokker-Planck equation provides a complete statistical description of a particle undergoing random motion in a solvent. In the presence of Lorentz force due to an external magnetic field, the Fokker-Planck equation picks up a tensorial coefficient, which reflects the anisotropy of the particle's motion. This tensor, however, cannot be interpreted as a diffusion tensor; there are antisymmetric terms which give rise to fluxes perpendicular to the density gradients. Here, we show that for an inhomogeneous magnetic field these nondiffusive fluxes have finite divergence and therefore affect the density evolution of the system. Only in the special cases of a uniform magnetic field or carefully chosen initial condition with the same full rotational symmetry as the magnetic field can these fluxes be ignored in the density evolution.

Reflex swallowing elicited by electrical stimulation in obstructive sleep apnea patients: A preliminary study

This study tested whether electrical stimulation of the pharyngeal mucosa is able to induce reliably the swallowing reflex in awake and asleep obstructive sleep apnea (OSA) patients, and whether the induced reflexes affect the sleep variables. In addition, the latency, occurrence, and morphology of swallows were evaluated. Eight patients received an esophageal catheter that was used on three consecutive nights for electrical stimulation and manometric recordings. The electrical stimulation proved itself safe, but its efficiency in inducing swallows sank from 80.0 % in awake to 37.4 % in sleeping subjects and was lowest in the sleep stage N3. The swallowing reflex was triggered with a mean latency of 3.69 ± 0.70 s, was predominantly induced in the hyperventilation phase, and had no significant effect on the subject's sleep variables. These findings indicate that electrical stimulation can more effectively trigger the swallowing reflex while the subjects are awake than during sleep without showing remarkable clinical benefits in terms of apnea-hypopnea index (AHI) improvement.

Implantation of the nyxoah bilateral hypoglossal nerve stimulator for obstructive sleep apnea

Objectives

This report describes the surgical implantation of a novel bilateral hypoglossal nerve stimulator (Genio system®, Nyxoah S.A., Belgium) and the successful treatment of a patient with moderate obstructive sleep apnea (OSA).

Study Design

Surgical technique description and case study report.

Methods

The bilateral implantable stimulator (IS) simultaneously stimulates both genioglossus (GG) muscles to reduce airway obstruction. At night, patients wear an activation chip under their chin that wirelessly transmits energy to the implant and enables the nerve stimulation. Surgical implantation of the IS is performed under general anesthesia by making a small incision above the hyoid bone and dissecting through the platysma, mylohyoid, and geniohyoid muscles to the GG muscle. The hypoglossal nerve branches are then identified, followed by suturing the IS in place. The system was evaluated in an otherwise healthy, 60-year-old woman with moderate OSA (apnea hypopnea index (AHI): 25/hr, nadir O₂ saturation: 78%). Appropriate stimulation settings were determined at 2-, 3-, and 6-months post implantation during polysomnography (PSG) and changes in apnea and hypopnea events and oxygen desaturation recorded.

Results

The surgery was well tolerated by the patient with an uneventful recovery. The PSG at 6 months showed that AHI per hour, obstructive apnea events per hour, hypopnea events per hour, and oxygen desaturation index have been reduced by 88%, 92%, 88%, and 97%, respectively, and nadir O₂ saturation improved to 91%.

Conclusions

The absence of complications and considerable reduction of apnea and hypopnea events in this case study help demonstrate the potential safety and efficacy of the bilateral hypoglossal nerve stimulator.

Level of Evidence

4.

Previous Surgery and Hypoglossal Nerve Stimulation for Obstructive Sleep Apnea

Objective

To examine whether previous palate or hypopharyngeal surgery was associated with efficacy of treatment of obstructive sleep apnea with hypoglossal nerve stimulation.

Study Design

Cohort (retrospective and prospective).

Setting

Eleven academic medical centers.

Subjects and Methods

Adults treated with hypoglossal nerve stimulation were enrolled in the ADHERE Registry. Outcomes were defined by the apnea-hypopnea index (AHI), in 3 ways: change in the AHI and 2 definitions of therapy response requiring ≥50% reduction in the AHI to a level <20 events/h (Response20) or 15 events/h (Response15). Previous palate and hypopharyngeal (tongue, epiglottis, or maxillofacial) procedures were documented. Linear and logistic regression examined the association between previous palate or hypopharyngeal surgery and outcomes, with adjustment for age, sex, and body mass index.

Results

The majority (73%, 217 of 299) had no previous palate or hypopharyngeal surgery, while 25% and 9% had previous palate or hypopharyngeal surgery, respectively, including 6% with previous palate and hypopharyngeal surgery. Baseline AHI (36.0 ± 15.6 events/h) decreased to 12.0 ± 13.3 at therapy titration ( P < .001) and 11.4 ± 12.6 at final follow-up ( P < .001). Any previous surgery, previous palate surgery, and previous hypopharyngeal surgery were not clearly associated with treatment response; for example, any previous surgery was associated with a 0.69 (95% CI: 0.37, 1.27) odds of response (Response20 measure) at therapy titration and a 0.55 (95% CI: 0.22, 1.34) odds of response (Response20 measure) at final follow-up.

Conclusion

Previous upper airway surgery was not clearly associated with efficacy of hypoglossal nerve stimulation.

Post-approval upper airway stimulation predictors of treatment effectiveness in the ADHERE registry

Upper airway stimulation (UAS) has been shown to reduce severity of obstructive sleep apnoea. The aim of this study was to identify predictors of UAS therapy response in an international multicentre registry.Patients who underwent UAS implantation in the United States and Germany were enrolled in an observational registry. Data collected included patient characteristics, apnoea/hypopnoea index (AHI), Epworth sleepiness scale (ESS), objective adherence, adverse events and patient satisfaction measures. Post hoc univariate and multiple logistic regression were performed to evaluate factors associated with treatment success.Between October 2016 and January 2018, 508 participants were enrolled from 14 centres. Median AHI was reduced from 34 to 7 events·h^-1, median ESS reduced from 12 to 7 from baseline to final visit at 12-month post-implant. In post hoc analyses, for each 1-year increase in age, there was a 4% increase in odds of treatment success. For each 1-unit increase in body mass index (BMI), there was 9% reduced odds of treatment success. In the multivariable model, age persisted in serving as statistically significant predictor of treatment success.In a large multicentre international registry, UAS is an effective treatment option with high patient satisfaction and low adverse events. Increasing age and reduced BMI are predictors of treatment response.

Uvulopalatopharyngoplasty with or without tonsillectomy in the treatment of adult obstructive sleep apnea - A systematic review

BACKGROUND

The most commonly performed surgical procedure for obstructive sleep apnea (OSA) is uvulopalatopharyngoplasty with or without tonsillectomy (UPPP ± TE). However, there is currently no review solely focusing on clinically relevant effects of standard UPPP technique with or without tonsillectomy as a monotherapy in patients with OSA.

METHODS

A systematic review and meta-analysis were performed to assess the effects of isolated UPPP ± TE in patients with OSA. Studies of any design referring to adult patients with obstructive sleep apnea diagnosed via polysomnography or comparable objective measures were considered, in which isolated "standard" UPPP ± TE was performed.

RESULTS

Forty-eight studies were included for the qualitative analysis. All but one study demonstrated a reduction in the frequency of respiratory events and success/response rates ranged from 35 to 95.2%. In the six studies that reported pre- and postoperative mean scores of the Epworth Sleepiness Scale (ESS), a reduction in sleepiness scores was demonstrated. Data addressing the effect of UPPP ± TE in comparison to no treatment or control were available from two randomized controlled trials (RCT). When pooling the data, UPPP ± TE was significantly more effective in reducing the apnea-hypopnea index (AHI) and Epworth Sleepiness Scale (ESS) (large effect): an AHI mean difference (MD) of -18.59 (95% CI -34.14, -3.04) and an ESS MD of -5.37 (95% CI -7,03, -3.72). Data addressing effect of UPPP ± TE in comparison to baseline was available from three RCT. When pooling the data, the AHI was reduced from a mean 35.4 to 17.9 (49.5% reduction); a MD of -20.41, 95% CI -32.78, -8.04 (-1.80, -1.15) (large effect). Various additional beneficial effects of UPPP ± TE were demonstrated including improvement in sexual function, ventricular function, sleep stages, serum lipid, depressive disorder and driving performance.

CONCLUSION

UPPP ± TE reduces respiratory events and daytime sleepiness in adult patients with OSA and UPPP ± TE is superior to non-treated controls in this regard. Further research is needed to establish the long-term benefit, the impact on cardiovascular morbidity and the role of UPPP ± TE in the variety of available treatment options for OSA.

Influence of MP 29-02 on ciliary beat frequency in human epithelial cells in vitro

PURPOSE

MP 29-02, which contains fluticasone propionate and azelastine hydrochloride, is used as a topical nasal application for the treatment of seasonal and perennial allergic rhinitis. Although a multitude of data is available on the clinical symptom reduction and treatment safety of MP 29-02, the effect of MP 29-02 on ciliary beat frequency (CBF) has not been evaluated thus far.

METHODS

MP 29-02-containing solution was applied at concentrations of 2.5, 5, 10, and 20% to 14 healthy subjects, and nasal ciliated epithelial cells were then visualized using a phase-contrast microscope. CBF was measured after the application of MP 29-02. For a comparison, fluticasone propionate was used. CBF measurements were then performed for 15 min at 22 °C. Ringer's solution was applied as a negative control.

RESULTS

MP 29-02 significantly reduced CBF at all the tested concentrations compared with that of the control group within the observation time. At a 2.5% concentration, MP 29-02 significantly reduced CBF from 6.81 Hz (SD ± 1.35 Hz) at baseline to 4.88 Hz (SD ± 1.52 Hz, p < 0.001) after 15 min. In contrast, for fluticasone propionate, a significant reduction was observed only with the 20% concentration after 5, 10, and 15 min.

CONCLUSIONS

MP 29-09 significantly reduced CB, with an almost linear relationship between the MP 29-09 concentration and reduction in CBF. For fluticasone propionate, a significant reduction of CBF was observed only at the highest analyzed concentration. The findings have implications for the long-term use of the MP 29-02. Yet, further clinical studies are needed to confirm these results in vivo, especially in patients with seasonal or perennial allergic rhinits.

Upper Airway Stimulation for Obstructive Sleep Apnea: Results from the ADHERE Registry

Objective

Upper airway stimulation (UAS) is an alternative treatment option for patients unable to tolerate continuous positive airway pressure (CPAP) for the treatment of obstructive sleep apnea (OSA). Studies support the safety and efficacy of this therapy. The aim of this registry is to collect retrospective and prospective objective and subjective outcome measures across multiple institutions in the United States and Germany. To date, it represents the largest cohort of patients studied with this therapy.

Study Design

Retrospective and prospective registry study.

Setting

Ten tertiary care hospitals in the United States and Germany.

Subjects and Methods

Patients were included who had moderate to severe OSA, were intolerant to CPAP, and were undergoing UAS implantation. Baseline demographic and sleep study data were collected. Objective and subjective treatment outcomes, adverse events, and patient and physician satisfaction were reviewed.

Results

The registry enrolled 301 patients between October 2016 and September 2017. Mean ± SD AHI decreased from 35.6 ± 15.3 to 10.2 ± 12.9 events per hour ( P < .0001), and Epworth Sleepiness Scale scores decreased from 11.9 ± 5.5 to 7.5 ± 4.7 ( P < .0001) from baseline to the posttitration visit. Patients utilized therapy for 6.5 hours per night. There were low rates of procedure- and device-related complications. Clinical global impression scores demonstrated that the majority of physicians (94%) saw improvement in their patients’ symptoms with therapy. The majority of patients (90%) were more satisfied with UAS than CPAP.

Conclusions

Across a multi-institutional registry, UAS therapy demonstrates significant improvement in subjective and objective OSA outcomes, good therapy adherence, and high patient satisfaction.

Polysomnographie bei Kindern: nicht nur an obstruktive Schlafapnoe denken

Heubi CH et al. Polysomnography in Pediatric Otolaryngology: If Not Obstructive Sleep Apnea, What Is It? Otolaryngol Head Neck Surg 2017; 157: 1053–1059

Ärzte der Abteilung für Hals-Nasen-Ohren-Heilkunde, Kopf- und Hals-Chirurgie der Universität von Cincinnati überprüften die Polysomnographie- Diagnosen von Kindern mit Verdacht auf schlafbezogene Atmungsstörungen (SBAS) und obstruktiver Schlafapnoe (OSA).

Influence of static magnetic fields on human myoblast/mesenchymal stem cell co‑cultures

The results of surgical repair of extensive muscle tissue defects are still of primary concern, leaving patients with residual cosmetic and functional impairments. Therefore, skeletal muscle tissue engineering attempts to grow functional neo‑tissue from human stem cells to promote tissue regeneration and support defect closure. Despite intensive research efforts, the goal of stable induction of myogenic differentiation in expanded human stem cells by using clinically feasible stimuli, has not yet been reached to a sufficient extent. Therefore, the present study investigated the differentiation potential of static magnetic fields (SMFs), using co‑cultures of human satellite cells and human mesenchymal stem cells (MSCs). It has previously been demonstrated that SMFs may act as a promising myogenic stimulus. Tests were performed on co‑cultures with and without SMF exposure, using growth medium [high growth factor concentrations (GM)] and differentiation medium [low growth factors concentrations (DM)]. AlamarBlue® assay‑based cell proliferation analysis revealed no significant difference between co‑cultures with, vs. without SMF stimulation, regardless of growth factor concentrations in the cell culture medium. To determine the degree of differentiation in co‑cultures under stimulation with SMFs, semi‑quantitative gene expression measurements of the following marker genes were performed: Desmin, myogenic factor 5, myogenic differentiation antigen 1, myogenin, adult myosin heavy chain 1 and skeletal muscle α1 actin. In neither GM nor DM was a steady, significant increase in marker gene expression detected. Verifying the gene expression findings, immunohistochemical antibody staining against differentiation markers revealed that SMF exposure did not enhance myogenic maturation. Therefore, SMF treatment of human satellite cell/MSC co‑cultures did not result in the desired increase in myogenic differentiation. Further studies are required to identify a suitable stimulus for skeletal muscle tissue engineering.

Heated air humidification versus cold air nebulization in newly tracheostomized patients

Background

After tracheostomy, the airway lacks an essential mechanism for warming and humidifying the inspired air with the consequent functional impairment and discomfort. The purpose of this study was to compare airway hydration with cold‐air nebulization versus heated high‐flow humidification on medical interventions and tracheal ciliary beat frequency (CBF).

Methods

Newly tracheostomized patients (n = 20) were treated either with cold‐air nebulization or heated humidification. The number of required tracheal suctioning procedures to clean the trachea and tracheal CBF were assessed.

Results

The number of required suctions per day was significantly lower in the heated humidification group with medians 3 versus 5 times per day. Mean CBF was significantly higher in the heated humidification group (6.36 ± 1.49 Hz) compared to the cold‐air nebulization group (3.99 ± 1.39 Hz).

Conclusion

The data suggest that heated humidification enhanced mucociliary transport leading to a reduced number of required suctioning procedures in the trachea, which may improve postoperative patient care.

[Treatment of supine position-related obstructive sleep apnea with smartphone applications]

BACKGROUND

Positional obstructive sleep apnea (POSA) is common in mild and moderate forms of obstructive sleep apnea (OSA). Two smartphone applications (apps) professing to avoid the supine position (SP) are available: for Android the "Apnea Sleep Position Trainer" and for iOS the "SomnoPose-Sleep Position Monitor". The smartphone needs to be attached to the chest to recognize SP, which then triggers a vibration alarm. This is intended to encourage the patient to change position and the vibration stops as soon as SP is left. These apps, however, have not yet undergone a systematic evaluation.

METHODS

Adult patients with polysomnographically diagnosed POSA were invited to participate in the study. POSA was defined as an apnea-hypopnea index (AHI) in SP >10, with AHI in a lateral position <10 and doubling of the AHI in SP. After 1 month, a control polysomnography (PSG) was performed and compliance (at least 4 h/night on 5 of 7 days) was evaluated after 6 months by phone. A sufficient therapy was defined as reduction in SP to <10% of the total sleep time and to an overall AHI <10.

RESULTS

Although 57 patients entered the study, 24 did not appear to the PSG control; therefore, 33 patients finished the study, of whom 25 were treated successfully. The overall AHI in 33 patients was reduced from 14.5 ± 9.0 to 9.5 ± 12.6 and the time in SP decreased significantly from 71.1 ± 50.5 to 25.4 ± 65.0 min. Compliance among the 25 continuously treated patients after 6 months was 79.2%.

CONCLUSION

Both smartphone apps have the capability to prevent PS in POSA patients and can potentially offer a cost-effective option in the treatment of POSA.

Innovative Surgery for Obstructive Sleep Apnea: Nerve Stimulator

Obstructive sleep apnea (OSA) as a multifactorial disease is treated with continuous positive airway pressure (CPAP) as the gold standard. Yet, if patients suffer from CPAP incompliance, traditional OSA surgery only targets morphological changes of the upper airway while neglecting functional issues. With the advent of upper airway stimulation, and in particular hypoglossal nerve stimulation as a treatment option, a highly effective, clinically proven and functional therapy with good evidence is available. This article gives a comprehensive overview of current and upcoming hypoglossal nerve stimulation systems (Inspire, ImThera, and Nyxoah), the specific advantages of this approach, the selection criteria and screening process, relevant clinical data, and a description of the different implantation procedures. Upper airway stimulation and hypoglossal nerve stimulation appears to be a long-term, low-morbidity treatment for moderate-to-severe OSA patients suffering from CPAP incompliance.

[Handling and reprocessing of semicritical medical devices in the ENT - a prospective study]

Numerous laws, guidelines and recommendations govern the handling and reprocessing of semi-critical medical devices in the field of ENT. Although mechanically reprocessing is characterized as a preferential, manual reprocessing is still conducted in most ENT clinics and medical practices for reasons of cost and practicability. In the presented study, we developed an optimized hygienic concept for reprocessing of medical products in the field of ENT.A demand analysis of rigid endoscopes and of ENT equipment was carried out based on hypothesis that only mechanical reprocessing was performed for the entire instrumentation. Additionally, patient-free activities like preparing instrumentation for examination were investigated. As a result, we could demonstrate that such patient-free activities represent a considerable time factor and as a consequence a cost factor in daily patient care. Necessary investments for only mechanical reprocessing of instrumentation including rigid endoscopes are considerably high, since number of endoscopes have to be kept very high.

Outcome after one year of upper airway stimulation for obstructive sleep apnea in a multicenter German post-market study

OBJECTIVE/HYPOTHESIS

Upper airway stimulation (UAS) of the hypoglossal nerve has been implemented in the routine clinical practice for patients with moderate-to-severe obstructive sleep apnea (OSA) who could not adhere to continuous positive airway pressure. This study reports objective and patient-reported outcome after 12 months of implantation.

STUDY DESIGN

Multicenter prospective single-arm study.

METHODS

Consecutive patients who received the UAS system (Inspire Medical Systems, Inc., Minneapolis, Minnesota, Maple Grove, MN, U.S.A.) were enrolled in three German centers. Key study exclusion criteria included body mass index > 35 kg/m² , apnea-hypopnea index (AHI) < 15 or > 65, or complete concentric collapse at the soft palate during sedated endoscopy. Data collection at 6- and 12-month visit include home sleep test and patient-reported outcome measures.

RESULTS

Among the total of 60 participants, the median AHI reduced from 28.6 to 9.5 from baseline to 12 months. Patient-reported outcome measured in Epworth Sleepiness Scale and Functional Outcomes of Sleep Questionnaire both improved significantly from baseline to 12 months. The average usage time was 39.1 ± 14.9 hours per week among all participants based on recordings by the implanted device. One patient requested a removal of the device for cosmetic and other personal reasons and was completed without sequelae.

CONCLUSION

This study supported that UAS is a safe and effective treatment option for patients with OSA in routine clinical practice.

LEVEL OF EVIDENCE

4. Laryngoscope, 128:509-515, 2018.

Outcomes of Upper Airway Stimulation for Obstructive Sleep Apnea in a Multicenter German Postmarket Study

Objective Selective stimulation of the hypoglossal nerve is a new surgical therapy for obstructive sleep apnea, with proven efficacy in well-designed clinical trials. The aim of the study is to obtain additional safety and efficacy data on the use of selective upper airway stimulation during daily clinical routine. Study Design Prospective single-arm study. Setting Three tertiary hospitals in Germany (Munich, Mannheim, Lübeck). Subjects and Methods A multicenter prospective single-arm study under a common implant and follow-up protocol took place in 3 German centers (Mannheim, Munich, Lübeck). Every patient who received an implant of selective upper airway stimulation was included in this trial (apnea-hypopnea index ≥15/h and ≤65/h and body mass index <35 kg/m²). Before and 6 months after surgery, a 2-night home sleep test was performed. Data regarding the safety and efficacy were collected. Results From July 2014 through October 2015, 60 patients were included. Every subject reported improvement in sleep and daytime symptoms. The average usage time of the system was 42.9 ± 11.9 h/wk. The median apnea-hypopnea index was significantly reduced at 6 months from 28.6/h to 8.3/h. No patient required surgical revision of the implanted system. Conclusion Selective upper airway stimulation is a safe and effective therapy for patients with obstructive sleep apnea and represents a powerful option for its surgical treatment.

CpG-Oligodeoxynucleotides in Chronic Rhinosinusitis Cell Culture

In chronic rhinosinusitis (CRS) an important feature is the infiltration of eosinophils, triggered by T-helper type 2 cells (TH2). Binding of the CpG oligodeoxynucleotide (CpG-ODN) ligand to toll-like receptor 9 (TLR9) induces a shift from a TH2- to a TH1-type response. We evaluated the hypothesis that CpG-ODN could reduce the predominantly TH2-driven response in our cultures.

MATERIALS AND METHODS

Twenty samples from CRS patients with (CRSwNP) and without nasal polyposis (CRSsNP) were cultivated. The expression of interleukin 5 (IL-5), eotaxin 3 and matrix metalloprotease 9 (MMP-9) were evaluated with and without CpG-ODN.

RESULTS

Addition of CpG did not influence the expression of IL-5 and eotaxin-3 DNA. Elevated MMP-9 expression in cultures from CRSwNP and CRSsNP patients could be established.

CONCLUSION

CpG does not reduce the attraction of eosinophils since no reduced IL-5 expression was measured in our cultures. Yet, MMP-9 - an important factor in tissue remodelling - was elevated in cultures from CRS patients.

Influence of static magnetic fields combined with human insulin-like growth factor 1 on human satellite cell cultures

Tissue engineering represents a promising research field, targeting the creation of new functional muscle tissue in vitro. The aim of the present study was to show the influence of static magnetic fields (SMF) and insulin-like growth factor-1 (IGF1), as enhancing stimuli on human satellite cell cultures, which are preferred sources of stem cells in engineering skeletal muscle tissue. To detect effects on myogenic maturation and proliferation, AlamarBlue® proliferation, assay and semi-quantitative reverse transcription-polymerase chain reaction of following markers was performed: desmin (DES), myogenic factor-5 (MYF5), myogenic differentiation antigen-1 (MYOD1), myogenin (MYOG), myosin heavy chain (MYH) and α1 actin (ACTA1). As a distinct marker of differentiation, immunohistochemical staining and fusion index determination was performed on satellite cell cultures stimulated with IGF1 and IGF1-plus-SMF with an intensity of 80 mT. Proliferation was increased by additional SMF application to IGF1-stimulated cell cultures on the first day of myogenesis. Relative gene expression of measured markers was increased by IGF1 application in the first days of myogenesis except for ACTA1. Additional SMF application enhanced this effect. Nevertheless we were unable to demonstrate the formation of contractile muscle tissue. Immunhistochemical staining verified muscle origin and all markers were displayed.

Trigeminal induced arousals during human sleep

BACKGROUND

Arousals caused by external stimuli during human sleep have been studied for most of the sensorial systems. It could be shown that a pure nasal trigeminal stimulus leads to arousals during sleep. The frequency of arousals increases dependent on the stimulus concentration. The aim of the study was to evaluate the influence of different stimulus durations on arousal frequency during different sleep stages.

METHODS

Ten young healthy volunteers with 20 nights of polysomnography were included in the study. Pure trigeminal stimulation with both different concentrations of CO2 (0, 10, 20, 40% v/v) and different stimulus durations (1, 3, 5, and 10 s) were applied during different sleep stages to the volunteers using an olfactometer. The application was performed during different sleep stages (light sleep, deep sleep, REM sleep).

RESULTS

The number of arousals increased with rising stimulus duration and stimulus concentration during each sleep stage.

CONCLUSION

Trigeminal stimuli during sleep led to arousals in dose- and time-dependent manner.

Anti-inflammatory effects of polihexanide and polyethylene glycol in an in vitro study in chronic rhinosinusitis

The majority of patients affected by chronic rhinosinusitis (CRS) suffer from eosinophilic infiltration. We hypothesised that polihexanide and polyethylene glycol as an antiseptic might alter the eosinophil-associated IL-5 and eotaxin-3 expression in CRS and also the expression of MMP-9, being involved in the tissue-remodelling in CRS. After obtaining samples from 10 CRS patients with (CRSwNP) and without nasal-polyposis (CRSsNP) and 2 patients with inverted-papilloma undergoing functional endoscopic sinus surgery (FESS), the expression of interleukin-5, eotaxin-3 and MMP-9 were evaluated by an ELISA assay with and without the tested agent. CRSwNP showed a significantly increased expression of IL-5. Polihexanide seems not to alter the attraction of eosinophils in patients with CRS via IL-5 expression. Also elevated levels of MMP-9 could not be reduced to normal values. But there exists statistically significant evidence that the self-amplification process of eosinophils via eotaxin-3 could be influenced by the administration of polihexanide.

[Position paper "Chemosensory testing for expert opinion in smell disorders"]

Providing expert opinion in the context of smell disorders is often challenging, not only with regard to general aspects of providing an expert opinion but particularly with regard to chemosensory testing. Currently there is no consensus which chemosensory test should be selected and how they should be executed. This positions paper from Committee on Olfaction and Gustation of the German Society of Otorhinolaryngology, Head and Neck Surgery aims to give concrete recommendations for chemosensory testing for providing expert opinion for smell disorders with regard to the selection and execution of these test.

In vitro effects of doxycycline on inflammatory cytokines and gelatinases in chronic rhinosinusitis

BACKGROUND/AIM

The pathophysiology of chronic rhinosinusitis (CRS) is unknown, but the majority of patients suffer from eosinophilic infiltration. We hypothesised that doxycycline might alter the eosinophil-associated expression of interleukin-5 (IL-5) and eotaxin-3 in CRS and also the expression of matrix metalloproteinase 9 (MMP-9), being involved in the tissue-remodelling in CRS.

MATERIALS AND METHODS

After obtaining samples from 10 CRS patients with and without nasal-polyposis undergoing functional endoscopic sinus surgery and two healthy individuals, the expression of IL-5, eotaxin-3 and MMP-9 were evaluated by an ELISA technique. The tested agent was doxycycline at 0.1 or 1 mg/ml.

RESULTS

IL-5 levels remained unchanged, but eotaxin-3 levels actually increased under doxycycline treatment. The only marker showing a slight drop was MMP-9, albeit not significant.

CONCLUSION

As first clinical trials with doxycycline in the treatment of CRS produced reasonable results we could demonstrate that the underlying pathology is more complex, and doxycycline affects only a part of the factors believed to support the chronic infection of the respiratory mucosa.

Does drug-induced sleep endoscopy change the treatment concept of patients with snoring and obstructive sleep apnea?

PURPOSE

Success rates of non-ventilation therapies for sleep disordered breathing (SDB) remain hardly acceptable. Drug-induced sleep endoscopy (DISE) tends to show the level and mechanism of obstruction and helps to specify therapy individually. Therefore, increasing success rates are expected. The objective of this study is to detect whether locations of treatment recommendations given after DISE are different to those made after clinical basic ENT (ear, nose, throat) examination (CBE).

METHODS

This study included patients with obstructive sleep apnea (OSA) and primary snoring who wish or require an alternative therapy to the gold standard, continuous positive airway pressure (CPAP). After CBE, a theoretical treatment recommendation was given comprising surgery (possible surgical target: soft palate, tonsils, tongue base, epiglottis) and mandibular advancement splints (MAS) or both. A second ENT specialist conducted a DISE and independently recommended a second therapy concept without knowing the first one. A third person compared both theoretical locations of treatment recommendations (CBE vs. DISE).

RESULTS

A total of 97 patients (eight female and 89 male, age 30-85 years, AHI 1.9-88.6/h, body mass index [BMI] 20.3-36.3 kg/m²) received two therapy recommendations. Regarding surgical options only, 63.9% of the examined patients got a different recommendation in at least one of four levels. If MAS was included, a change was found in 78.4% of the patients. Subdivided into each type of intervention, the following changes were found in the therapy concept: 24.7% (n = 24/97) soft palate, 12.4% (n = 12/97) tonsils, 33.0% (n = 32/97) tongue base, 27.8% (n = 27/97) epiglottis, 38.1% (n = 37/97) MAS.

CONCLUSIONS

DISE shows a relevant influence on the location of treatment recommendation. Thus, a change in success rates of non-CPAP therapy in OSA and snoring appears possible.

Ciliary function of the nose in patients with Osler`s disease and the effect of topically applied estrogens as a nose ointment

BACKGROUND

In recent years, the positive effect of topically applied estriol nose ointment in the adjuvant therapy of Morbus-Rendu-Osler (HHT) has been proven. Due to the induced metaplasia, a complete destruction of the ciliated cells may be expected. However, data regarding the ciliary function of HHT patients with and without the use of topical estriol application are currently lacking.

METHODOLOGY/PRINCIPAL

Ciliated samples were obtained by gently brushing the inferior nasal turbinate of 19 healthy volunteers and 15 patients with known HHT (8 of them regularly using 0.1% estriol nose ointment for 2 years (HHTwE) and 7 of them not using the ointment in the last 12 months (HHTwoE)). Analysis was done with an inverted phase contrast microscope connected to a high-speed digital camera. Recorded parameters were the visual integrity (VI) of the ciliary beat and its frequency (CBF) in Hz.

RESULTS

The VI index of all samples showed an undisrupted, even beating pattern with a difference between the three groups. The mean CBF in all HHT patients was reduced compared to the control group`s mean CBF. Within the HHT group itself, the mean CBF was reduced in the HHTwE group compared to the HHTwoE group.

CONCLUSIONS

The ciliary beat frequency of HHT patients is impaired compared to the control group and even more so if the HHT patients topically apply estriol more than 6 months. An undisrupted beating pattern is found in the HHTwE group despite the fact that estrogens induce a transformation of the ciliated columnar into a keratinizing squamous epithelium. This data may justify the adjuvant application of estriol as a nose ointment in the treatment of epistaxis in HHT patients without the fear of damage to the nose`s mucus clearance.

Palatal implants in the treatment of obstructive sleep apnea: a randomised, placebo-controlled single-centre trial

Palatal implants have been used to treat snoring and mild to moderate obstructive sleep apnea (OSA). Two previous controlled trials have published conflicting results regarding the effects of palatal implants on objective outcome measures, although they both could demonstrate superiority over placebo. The aim of the present study was to assess the effects of palatal implants in patients with mild to moderate sleep apnea in a randomised, placebo-controlled trial. Twenty-two patients with mild to moderate OSA (AHI 18 ± 5, BMI 28 ± 3, age 51 ± 13 years) due to palatal obstruction were enrolled in this randomised, double-blind, placebo-controlled trial. Respiratory parameters and sleep efficiency (evaluated by polysomnography), snoring (evaluated by the bed partner), and daytime sleepiness (evaluated by ESS) were assessed before and 90 days after surgery. One patient in each group did not show up for follow-up. The AHI, HI and LSAT showed statistically significant improvement in the treatment group (p < 0.05). Snoring as rated by bed partners also showed statistically significant improvement within the treatment group (p = 0.025). There was no statistical difference when comparing the means of the treatment group with the placebo group. There were no peri- or post-operative complications and no extrusions during the follow-up period. The study supports the idea that palatal implants lead to a reduction in respiratory events in patients with mild to moderate OSA, although a statistically significant superiority of palatal implants over placebo could not be demonstrated in this trial.

Chemotherapeutic alteration of β-catenin and c-kit expression by imatinib in p16-positive squamous cell carcinoma compared to HPV-negative HNSCC cells in vitro

The most common neoplasm arising in the upper aerodigestive tract is head and neck squamous cell carcinoma (HNSCC). Tumor growth, invasion and systemic dissemination is a multistep process of dysregulated cellular signaling pathways and an altered cell-cell and cell-matrix interaction. Aberrant Wnt/β-catenin signaling is linked to tumor development and dissemination in several tumor entities. β-catenin is a multifunctional protein within the canonical Wnt pathway, which is an important factor for reducing cell-cell adhesion in malignant tissue and for triggering cell cycle progression and unscheduled proliferation. Another pivotal factor in carcinogenesis is the tyrosine kinase receptor c-kit, which in the case of dysregulated expression is associated with neoplastic transformation in epithelial tissue. This study evaluates the expression pattern of secreted and nuclear β-catenin and c-kit in p16-positive and HPV-negative squamous cell carcinomas (SCC) and the vulnerability of therapy with the tyrosine kinase inhibitor imatinib as a potential targeted treatment modality compared to platinum-based chemotherapeutic drugs. The different squamous tumor cell lines were incubated with increasing concentrations of carboplatin (3 or 7.5 µmol/ml) and imatinib (18 or 30 µmol/ml). ELISA and immunohistochemical methods were carried out after 48, 72, 120, 192 and 240 h. We detected a reliable trend towards significantly decreased cytosolic and nuclear β-catenin and c-kit expression levels in p16-positive SCC and non-HPV HNSCC cells induced by imatinib exposure for an extended incubation period, whereas platinum-based agents had no or, at best, a slight influence. Virus-transformed squamous cell carcinoma (CERV196) cells were characterized by a reduced susceptibility to an imatinib-altered β-catenin expression. Further studies are planned to investigate this observance in HPV-positive HNSCC in vitro. The implementation of a selective molecular therapy in established chemotherapeutic regimes may enhance the efficacy of platinum-based chemotherapy without increased toxicity and could thus improve the clinical outcome in HNSCC, irrespective of the HPV status.

Chemotherapeutic alteration of VEGF-/PDGF- and PDGF-Rα/β expression by imatinib in HPV-transformed squamous cell carcinoma compared to HPV-negative HNSCC in vitro

Head and neck squamous cell carcinoma (HNSCC) is an aggressive epithelial malignancy known to be the most common neoplasm appearing in the upper aerodigestive tract. The poor five-year survival rate has remained unchanged in the last decades despite the emergence of improved techniques in surgery, radiation and chemotherapy. In the last 20 years awareness of a subset of squamous cell carcinomas induced by oncogenic forms of the human papilloma virus (HPV) (high-risk types 16 and 18) has increased. The incidence of HPV-associated oropharyngeal cancer is rising, indicating the increased importance of the viral etiology. Cell proliferation, migration, induction of tumor vascularization and carcinogenesis, as well as invasion facilitation is regulated by a variety of angiogenic peptides like PDGF, PDGF-R and VEGF. They might be an encouraging target for biological anticancer therapy by inhibiting disrupted cellular signaling pathways. Imatinib has been shown to target specific tyrosine kinases, inhibiting proliferation in various cancer entities. The purpose of this study was to evaluate the expression pattern of angiogenic factors (VEGF, PDGF and PDGF-R) in HPV-positive (p16-CERV196 SCC) and (-negative squamous cell carcinoma (HNSCC). The study also evaluated the vulnerability of anti-angiogenesis therapy depending on the HPV status as potential treatment modality compared to established platinum-based chemotherapeutic drugs. The different squamous tumor cell lines were incubated with increasing concentrations of carboplatin (3 and 7.5 µmol) and imatinib (18 and 30 µmol). ELISA immunohistochemical methods were carried out after 48, 72, 120, 192 and 240 h. We demonstrated a significant reduction of VEGF and PDGF-Rα/β expression patterns after incubation of imatinib in ELISA and immunohistochemical methods, irrespective of the HPV status of the tumor cells, whereas the application of carboplatin had no impact on the expression of angiogenic peptides. Viral oncogen-transformed squamous cell carcinoma (CERV196) cells were characterized by a reduced susceptibility for an imatinib-altered VEGF expression. Further studies are planned to investigate this observance in HPV-positive HNSCC in vitro. The implementation of a selective molecular anti-angiogenic therapy in established chemotherapeutic regimens may enhance the efficacy of platinum-based chemotherapy without an increased toxicity profile and could thus improve the clinical outcome in HNSCC, irrespective of the HPV status.

Down-regulation of MMP-2 expression due to inhibition of receptor tyrosine kinases by imatinib and carboplatin in HNSCC

Squamous cell carcinoma of the head and neck (HNSCC) is the most common neoplasm arising in the upper aerodigestive tract. Unfortunately, the survival for this type of cancer has not improved significantly in the past 25 years. To enhance the survival rate multimodal therapy regimens have been set up. In these regimens chemotherapy plays a pivotal role in the majority of advanced cases. Transmembrane protein- tyrosine kinases (PTK) are fundamental elements of the signal transduction. In consequence, they might be promising targets for cancer therapy. Imatinib (STI 571) was originally designed to inhibit the BCR-ABL tyrosine kinase in chronic myeloid leukemia. But imatinib also has an inhibitory impact on the PTK receptor c-kit and on its PTK activity. Furthermore, growth and invasion of HNSCC are strongly influenced by the extracellular matrix (ECM). The ECM is altered by matrix metalloproteinases (MMP). In this study, we incubated different HNSCC cell lines with rising concentrations of imatinib and/or carboplatin. After an incubation time of up to 10 days, we evaluated c-kit, MMP-2 and MMP-14 by ELISA techniques and immunohistochemical methods. Especially the combination of 7.5 μmol carboplatin with 30 μmol imatinib resulted in a significant decrease in MMP-2 expression in all observed cell lines (p<0.05). We did not demonstrate a significant alteration in c-kit expression by imatinib and carboplatin. We observed an increase in apoptosis in HNSCC cells by the combination of the two observed chemotherapeutic drugs. In all cell lines tested, expression of c-kit and MMP could be demonstrated. Our results indicate that MMP-2 expression was suppressed in the presence of imatinib. Thus, imatinib may exert in part its inhibitory effect on malignant cell growth via the blockage of the signal transduction of PTK receptors. Further studies are warranted, especially one keeping in mind the moderate toxicity of imatinib.

Synergistic effects of imatinib and carboplatin on VEGF, PDGF and PDGF-Rα/ß expression in squamous cell carcinoma of the head and neck in vitro

Head and neck squamous cell carcinoma (HNSCC) is an aggressive epithelial malignancy. The development of new treatment modalities in order to improve long-term survival of patients with HNSCC is imperative. Numerous studies have demonstrated that carcinogenesis and tumor cell dissemination is influenced by the tumor microenvironment. The protein-kinase-receptors (PTKs) are essential elements of the intracellular signal transduction pathway and regulate cell growth, development and apoptosis. Cell proliferation, migration, induction of tumor vascularization and carcinogenesis, invasion is regulated by a variety of angiogenic factors, such as PDGF (platelet-derived growth factor), VEGF (vascular endothelial growth factor) and their respective tyrosine kinase receptors (PDGF-R and VEGF-R). They present promising targets for anti-cancer therapy through abrogation of impaired signaling pathways. Indeed, imatinib, a small molecule drug targeting these protein kinases, has antiproliferative effects in several cancer types. The purpose of this study was to investigate the potential synergism of imatinib and carboplatin on the expression of PDGF, PDGF-R α/ß and VEGF in different HNSCC cell lines. Several tumor cell lines were subjected to increasing concentrations of carboplatin (3 and 7.5 µmol/l) and imatinib (18 and 30 µmol/l) and ELISA, immunohistochemical methods and RQ-PRC after 48, 72, 120 and 240 h were used to assess their expression levels. While PDGF-Rα/ß expression was unimpaired at lower imatinib concentrations (18 µmol/l), PDGF-Rα/ß expression was suppressed at 30 µmol/l, and suppression was enhanced by the presence of carboplatin. By RQ-PCR, a significant reduction of PDGF-Rα/ß expression was detected (p<0.5). We observed explicit significant reduction in VEGF levels with increasing concentrations of imatinib and with the combination of the two chemotherapeutic drugs (p<0.5). We report for the first time evidence of synergism of imatinib and carboplatin in suppressing VEGF, PDGF and PDGF-Rα/ß expression in HNSCC.

[Obstructive sleep apnea in children]

Obstructive sleep apnea (OSA) is a common disease in children. It is defined by the onset of snoring, hypopneas or apneas with impaired sleep and daytime function. Obstruction of the upper airway during sleep is the underlying pathogenetic mechanism. It is caused either by an anatomic obstruction, increased airway collapsibility or both. Normally OSA in children is diagnosed by its typical anamnesis including snoring and exerted breathing patterns. The diagnosis is confirmed in unclear cases using polysomnography. Treatment consists of conservative measures such as weight reduction and--provided appropriate anatomical findings exist--adenotonsillectomy or adenotonsillotomy. Surgery is an effective treatment for OSA in children as proven by numerous studies of high evidence levels.

ENT manifestations in patients with primary ciliary dyskinesia: prevalence and significance of otorhinolaryngologic co-morbidities

Primary ciliary dyskinesia (PCD) is a rare inherited disease with a prevalence of about 1:20,000. The underlying pathogenesis is disrupted ciliary function, which results in delayed mucus transportation leading to chronic inflammation, mainly in the upper and lower respiratory tract. Although the pathogenesis of the disease and its clinical presentation is somewhat understood, data regarding the prevalence of accompanying symptoms is limited, especially in the field of otorhinolaryngology. A total of 44 patients diagnosed with PCD answered a questionnaire regarding the diagnosis and clinical presentation of the disease, their medical history and clinical manifestations, and medical treatment in the field of otorhinolaryngology. The majority of participants (70%) had seen a physician more than 50 times before the diagnosis was made at an average age of 10.9 ± 14.4 years. As much as 59% of all patients had recurring problems at the paranasal sinuses and 69% of these patients needed corresponding surgical intervention. Even more patients (81%) suffered from recurring otitis media and, as a result, 78% of these patients underwent paracentesis with temporary tympanostomy tubes at least once at an average age of 9.5 ± 13.0 years. Otorhinolaryngologic symptoms, especially chronic otitis media and chronic rhinosinusitis, are frequently associated with PCD. Surgical intervention to treat these symptoms is common. The awareness of this disease should be raised, especially among ENT physicians, and surgical intervention should be indicated carefully.

Time-dependent changes in nasal ciliary beat frequency

As the ex vivo lifetime of nasal ciliary cells is limited, these cells have to be transferred to a culture medium for analysis with vital cytology immediately. Although the ciliary beat frequency (CBF) is likely to change over time, sufficient data regarding changes in the ex vivo CBF has not been published to date. In the present study, nasal epithelial cells were harvested from the mucosa of the inferior turbinate of 19 healthy volunteers with a cytology brush. Beating cilia were visualized with phase-contrast microscopy. Over a 12-h timeframe, 2 s epochs of video were captured every 5 min from the identical group of cells using a high-speed digital camera with a sampling rate of 100 fps. Temperature was maintained at about 22 degrees C and controlled by an infrared pyrometer. The CBF rapidly increased by 47 +/- 53% during the first 3 h of measurement. A relative plateau followed this increase from 3 to 9 h. After 9 h, CBF reduced linearly. After 12 h, the mean frequency reduced to 20 +/- 69% of baseline. However, there was considerable variance between the samples. The initial increase in CBF has not been reported previously. This interval seems to be unsuitable for meaningful measurements. Measurements of CBF are most reliable during the plateau phase between 3 and 9 h. After 9 h, there is clearly a significant decrease in CBF, together with a considerable interindividual variance.

Direct visualization of random crystallization and melting in arrays of nanometer-size polymer crystals

Using tapping mode atomic force microscopy, we visualized in direct space and time resolved the changes in viscoelastic properties during crystallization and melting of polyethyleneoxide in 12 nm spheres of a block copolymer mesophase. All spheres crystallized individually and independently, randomly distributed sphere by sphere. Melting of the confined crystals also proceeded in a stochastic manner. Not all spheres melted at the same temperature, indicating different degrees of order of the individual nanometer-size polymer crystals. The independence of the spheres opens the possibility to manipulate material properties of surfaces at the nanometer scale.

Liquidlike morphological transformations in monolamellar polymer crystals

We performed annealing experiments on monolamellar polyethyleneoxid crystals. Even well below the melting point, local relaxations of metastable folded states led to pronounced liquidlike morphological changes on a micron scale of shape and perimeter of the crystalline domains, similar to dewetting of liquids. First, a rim of less folded molecules was formed around the lamellae, making relaxations of the interior difficult. On longer time scales, hole formation within these domains was observed. Our experiments showed that, due to such spatial anisotropy in relaxations, polymer crystal morphology depends on the thermal pathway taken, implying that a time-temperature superposition principle does not apply.