Search PubMed⌕ Search

Biomedical subjects

W Stoll

Publications and source records attributed to W Stoll.

At least 19 recordsLinked to original sources
PubMed2006

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.

Cilia↗
PubMed2006

Induction of CXC chemokines in A549 airway epithelial cells by trypsin and staphylococcal proteases - a possible route for neutrophilic inflammation in chronic rhinosinusitis.

While various microorganisms have been recovered from patients with chronic rhinosinusitis, the inflammatory impact of virulence factors, in particular proteases from Staphylococcus aureus and coagulase negative staphylococci on the nasal epithelium, has not yet been investigated. Expression of CXC chemokines was determined in the epithelium of patients with chronic rhinosinusitis by immunohistochemistry. In a cell culture system of A549 respiratory epithelial cells, chemokine levels were quantified by enzyme-linked immunosorbent assay (ELISA) after stimulation with supernatants originating from three different staphylococcal strains or with trypsin, representing a serine protease. Inhibition experiments were performed with prednisolone, with the serine protease inhibitor 4-(2-aminoethyl)-benzenesulphonylfluoride (AEBSF) and with the nuclear transcription factor (NF)-kappaBeta inhibitor (2E)-3-[[4-(1,1-dimethylethyl)phenyl]sulphonyl]-2-propenenitrite (BAY) 11-7085. Electromobility shift assays (EMSA) were used to demonstrate NF-kappaB-dependent protein synthesis. CXC chemokines interleukin (IL)-8, growth-related oncogene alpha (GRO-alpha) and granulocyte chemotactic protein-2 (GCP-2) were expressed in the patients' epithelium whereas epithelial cell-derived neutrophil attractant 78 (ENA-78) was rarely detected. In A549 cells, chemokines IL-8, ENA-78 and GRO-alpha but not GCP-2 were induced by trypsin and almost equal levels were induced by staphylococcal supernatants. IL-8, GRO-alpha and ENA-78 synthesis was suppressed almost completely by AEBSF and BAY 11-7085, whereas prednisolone reduced chemokine levels differentially dependent on the supernatant added. CXC chemokines were detectable in the epithelium of patients with chronic rhinosinusitis. Staphylococcal serine proteases induced CXC chemokines in A549 cells, probably by the activation of proteases activated receptors, and thus might potentially be involved in neutrophilic inflammation in chronic sinusitis.

Adult↗
PubMed2005

[Principles of hearing aids].

The diagnostic and therapy of hearing impairment is one of the main tasks of the Otolaryngologist. This article deals with the treatment of hearing aids in adults and young persons according to the laws and the guidelines of the "Heil- und Hilfsmittelrichtlinien" in Germany. It shall serve the Otolaryngologist as a guideline. The first part of the article is about the indications of hearing aids laid down in the "Heil- und Hilfsmittelrichtlinien". Especially the possibilities of the treatment of uni- and bilateral hearing impairment are discussed. The principles of the actual hearing aids technology are described to support the Otolaryngologist in his consultation.

Adolescent↗
PubMed2005

[Principles of hearing aids].

The diagnostic and therapy of hearing impairment is one of the main tasks of the Otolaryngologist. This article deals with the treatment of hearing aids in adults and young persons according to the laws and the guidelines of the "Heil- und Hilfsmittelrichtlinien" in Germany. It shall serve the Otolaryngologist as a guideline. The second part of the article is about the different strategies to adjust hearing aids. Then the examination of the hearing aids by the otolaryngologist is described. Finally the importance of aftercare is stressed and the future of hearing aids in Germany according to the concept of "OHRWELL" is pointed out.

Auditory Threshold↗
PubMed2005

Neutrophil chemokines in epithelial inflammatory processes of human tonsils.

CXC chemokines are thought to play an important role at sites of inflammation. Because ELR(+) CXC chemokines are expressed in different types of tonsillitis we investigated the role of the surface/crypt epithelium of human tonsils in producing ELR(+) CXC chemokines: interleukin (IL)-8 (CXCL8), ENA-78 (CXCL5), GRO-alpha (CXCL1) and GCP-2 (CXCL6). Tonsillar tissue was obtained from patients undergoing tonsillectomy and chemokine expression was investigated by means of immunohistochemistry. A549 cells were used as a model to study kinetics of chemokine expression in epithelial cells. Cells were stimulated with tumour necrosis factor (TNF)-alpha, lipopolysaccharide (LPS) and supernatants derived from aerobic/anaerobic Staphylococcus aureus strains. Chemokine expression was measured by quantitative reverse transcription-polymerase chain reaction (RT-PCR) and enzyme-linked immunosorbent assay (ELISA). We observed epithelial expression of IL-8, GRO-alpha and GCP-2 in different types of tonsillitis, whereas ENA-78 was rarely expressed. In A549 cells abundant expression of ENA-78 was detected. IL-8 and GCP-2 are expressed in an acute type of tonsillitis whereas GRO-alpha was frequently detectable both in chronically and acutely inflamed tonsils. ENA-78 does not seem to play a pivotal role in tonsillitis in vivo.

Adolescent↗
PubMed2004

Lateral inhibition and habituation of the human auditory cortex.

The goal of this study was to compare the lateral inhibition and the habituation in the human auditory cortex, two important physiological effects during auditory processing that can be reliably measured by means of magnetoencephalography when recording auditory evoked fields. Applying 40-Hz amplitude-modulated stimuli allowed us to record simultaneously the slow transient evoked and the steady-state fields and thus to characterize the lateral inhibition and the habituation effect in primary and non-primary auditory cortical structures. The main finding of the study is that the lateral inhibition effect of non-primary auditory areas as measured on the major component of the slow transient auditory evoked field (N1) is significantly stronger than the corresponding habituation effect. By contrast, this effect was not observed for the 40-Hz steady-state fields, characterizing the activation of the primary auditory cortex in humans. The results might be interpreted as (i) evidence that the inhibition mediated by lateral connections is stronger than the habituation of excitatory neurons in the non-primary auditory cortex and (ii) the processing hierarchy in the human auditory cortex is demonstrated by the different behaviour of lateral inhibition and habituation in primary and non-primary auditory cortical structures.

Acoustic Stimulation↗
PubMed2003

[Primary nasal epithelial cells and fibroblasts have inflammation-inducing functions].

BACKGROUND: The appearance of neutrophils in rhinitis and sinusitis led to the working hypothesis that neutrophil-specific attractants commonly called chemokines are generated by stimulation with proinflammatory cytokines and bacteria. The receptor mechanism of chemokine synthesis by bacterial products is under discussion and still has to be elucidated. PATIENTS AND METHODS: The primary nasal cultures of epithelial cells and fibroblasts ( n=4) were incubated with TNF-alpha (tumor necrosis factor) for 24 and 72 h. Bacterial stimulation of the cell cultures was performed by adding supernatants from the mucoid phenotype of Pseudomonas aeruginosa (PA01) in dilution 1:5 for 24 and 72 h. Supernatants were collected and the concentration of the chemokines interleukin-8 (IL-8), GRO-alpha (growth-related oncogene-alpha), and ENA-78 (epithelial neutrophil-activating peptide) were determined by ELISA technique. Our results revealed that the protein concentration of the chemokines GRO-alpha and IL-8 was upregulated by TNF-alpha as well as by bacterial supernatants in epithelial cells. CONCLUSION: We conclude that GRO-alpha and IL-8 were inducible by bacterial supernatants in nasal epithelial cells and fibroblasts.

Chemokine CXCL1↗
PubMed2003

[Prognostic factors in hearing recovery following sudden unilateral deafness].

A perilymph fistula is a possible cause for sudden unilateral sensory deafness. In this retrospective study the data of 73 patients with unilateral sudden deafness were analyzed. All of them underwent an exploratory tympanotomy during which both windows were packed with soft tissue. Postoperatively all patients received rheological therapy with pentoxifyllin and steroids. The following possible prognostic indicators were analyzed: age, sex, tinnitus, vertigo, vomiting, spontaneous nystagmus, positive fistula test, time between onset of symptoms and therapy, intraoperative proof of a perilymph fistula, and signs of barotrauma in the patient's history. A significant postoperative recovery of the hearing loss (>20%) was found in 29 patients (39.7%) (group 1), and 44 patients (60.3%) showed only an increase of <20% (group 2). The statistical analyses showed the following significant difference: The symptoms vertigo (p=0.002) and spontaneous nystagmus (p=0.014) occurred more frequently in group 2 (patients with a poor hearing recovery) than in group 1. Patients with a barotrauma,however, had an overproportionally good outcome (50-100% hearing recovery). A perilymph fistula was seen intraoperatively equally often in both groups. In summary, the symptoms vertigo and spontaneous nystagmus are indicators of complex damage in cases of sudden deafness and are associated with a worse prognosis concerning hearing recovery. Exploratory tympanotomy in combination with drug treatment is a reasonable therapy as an ultima ratio in every case of unilateral sudden deafness.

Adolescent↗
PubMed2003

[Therapeutic management of necrotizing neck infections].

BACKGROUND: Necrotizing neck infections are uncommon soft-tissue infections, usually caused by virulent, toxin producing bacteria. Necrotizing fasciitis represents a special form of necrotizing soft tissue infection with a mortality rate of up to 76% even though aggressive therapy is recommended. PATIENTS AND METHODS: In the last 2 years we treated four patients with severe necrotizing neck infections and five suffering from necrotizing fasciitis. RESULTS: Microbiological analysis revealed mixed infections with Candida albicans, Streptococcus pyogenes, Fusobacterium, Proprioni bacteria and Staphylococcus. The surgical management was not only restricted to drainage, but also included functional neck dissection in order minimize the spread of the disease. Eight of our patients recovered completely, but one died due to toxic shock as consequence of a delayed in therapy. CONCLUSION: Complete recovery of patients suffering from necrotizing fasciitis depends on early and aggressive surgical therapy including neck dissection and drainage as well as an interdisciplinary strategy of conservative therapy. Hyperbaric oxygen should be considered as a treatment adjunct in patients with necrotizing fasciitis if surgery and antibiotic treatment fail.

Adult↗
PubMed2003

[Drug treatment for vertigo].

The approach to drug treatment of vertigo is almost exclusively symptomatic. There are 3 major goals for drug treatment of vertigo: to eliminate the hallucination of motion, to reduce the accompanying neurovegetative and psychoaffective signs (nausea, vomiting, anxiety), and to enhance the process of "vestibular compensation" to allow the brain to find a new sensory equilibrium in spite of the vestibular lesion. Three different types of vertigo drug treatment must be distinguished: the treatment of acute vertigo attacks, the treatment of chronic vertigo, and the treatment of patients with Menière's disease to avoid vertigo attacks. Furthermore, this paper deals with the treatment of motion sickness and of the postoperative nausea and vomiting.

Antiemetics↗
PubMed2002

[Differential diagnosis and management of retropharyngeal space-occupying lesions].

BACKGROUND: Diseases of the retropharyngeal space place high request on the diagnostic and therapeutic knowledge of the otorhinolaryngologist. METHODS: Under consideration of six own cases and of all other published case reports, this inhomogeneous symptom is analysed systematically. RESULTS: Commonly, these alterations of the retropharyngeal space are observed incidentally during routine throat examination or in patients suffering from dyspnoea, dysphagia, dysphonia, sleep apnoea syndrome or neck pain. Six own cases show the very inhomogeneous aetiology (retropharyngeal abscess, lipoma, malignant schwannoma, sarcoidosis, aberrant internal carotid artery, Forestier disease). Therefore, before surgery, a sufficient radiologic diagnosis (lateral neck radiography and CT or MRI respectively) is necessary to avoid grave complications (injury to the cervical spine, the brain, the spinal cord or the internal carotid artery). A tissue sample can be obtained by the transoral approach while the lateral cervical approach seems to be the better way to treat a retropharyngeal abscess. CONCLUSION: Because of the very different aetiology of retropharyngeal space diseases the therapy finally depends on the definite diagnosis.

Adult↗
PubMed2002

[Clinical aspects of abscess development in parotitis].

OBJECTIVE: The purpose of this paper was to analyse parotideal abscesses on the basis of a larger number of patients. PATIENTS AND METHODS: The data of 36 patients (mean age 44 years) with a parotideal abscess was analysed. RESULTS: Ultrasound scan was always necessary to verify the diagnosis. The surgical drainage was done under myoelectric monitoring of the facial nerve. Only in 1 patient a temporary minor paralysis of the mandibular branch was noticed. The most common bacteria were Staph. aureus, Streptococcus, and Peptostreptococcus. In 2 cases a tuberculosis and in 2 children an atypical mycobacterial infection was discovered. In another patient a metastasis of a squamous cell carcinoma was found. CONCLUSIONS: In every patient with an acute swelling of the parotid region without consideration of age, number of leucocytes or a typical fluctuation, an ultrasound scan should be used. The surgical drainage of the abscess should be done under myoelectric monitoring (Cave: muscle relaxant). In every case, a specimen for microbiological analysis (bacterial determination) and a biopsy (to exclude malignoma or atypical mycobacteria) are necessary. A peri- and post-operative therapy with a combination of aminopenicillin and clavulanic acid or with cephalosporine is recommended.

Abscess↗
PubMed2002

[Trauma of the Membranous Trachea Managed by the ENT-Surgeon].

BACKGROUND: Isolated perforations of the membranous trachea are extremely rare but potentially life-threatening complications of endotracheal intubations and minimally invasive tracheostomy techniques. Most of the case-reports have been written by thoracic surgeons or anesthesiologists but both the diagnostic procedures and the therapy are not standardized. The aim of this study was to evaluate the position of the ENT-surgery in the management of these lesions. PATIENTS AND METHODS: Over a period of 6 years we treated 5 females, 3 males and 3 children with iatrogenic lacerations of the posterior tracheal wall. The lesions were complications of percutaneous tracheostomies or emergent intubations. The charts and videoprints of each patient were reviewed. RESULTS: Clinical presentation was marked in all patients by the characteristical symptoms of paratracheal air leakage, i.e. pneumothorax, emphysema or airway obstruction. In 6 patients the onset of the symptoms occurred with a significant delay until to 2 days after the lesion was originated. Perforations were located at the distal third (8) and at the medial third (2) of the trachea or the subglottic area (1) and had a vertical shape with a length of 0.3-5.5 cm. Surgical repair using a transtracheal cervical approach or an endoscopical procedure was performed in 8 cases. 3 lesions having a length below 2 cm were treated nonoperatively. Outcome was excellent in all patients but a certain percentage of them claimed cough and dysphonia one or more years after the acute phase. CONCLUSIONS: Because of their life-threatening character perforations of the membranous trachea must be diagnosed as soon as possible. However, the clinical presentation is not obvious in many cases. For the exact detection of the perforations rigid endoscopy is superior to flexible technique. The early surgical repair is recommended for the majority of the cases. Therefore, the transtracheal approach and endoscopical procedures are favorized. Moreover, these methods used routinely in ENT-surgery are also appropriate for lesions of the distal part of the membranous trachea and can be an alternative to the more invasive thoracotomy. Conservative treatment strategies should be limited to selected patients with small lacerations.

Adolescent↗
PubMed2002

[Diagnosis and management of benign paroxysmal positional vertigo].

Benign paroxysmal positional vertigo (BPPV) is a common disorder of the vestibular labyrinth which should be suspected in all patients with a history of vertigo during changes of head position. The BPPV appears to be caused by free-floating debris in the posterior semicircular canal. The diagnosis is confirmed by eliciting characteristic symptoms during the Dix-Hallpike test. Although the BPPV usually is a self-limited disorder treatment with a specific bedside maneuver is effective and can shorten the duration of symptoms.

Female↗
PubMed2001

[Voice change and laryngeal obstruction caused by a median thyroglossal duct cyst].

Thyroglossal duct cysts are common primary neck tumors, resulting from remnants of the ductus thyroglossus. They can occur at any point along the migratory path of the thyroid gland anlage until the 2nd or 3rd decade of life. The usual symptoms leading to the diagnosis are painless midline neck masses orfistulas. Despite their close proximity, the cysts normally do not affect the larynx. We report on the eighth case mentioned in the world literature of a thyroglossal duct cyst invading the larynx in a 62-year-old patient. Preoperatively, the voice of the patient sounded metallic, and the frequency of the voice field was reduced. Postoperatively, the voice onset was physiological, and the voice increased by an octave in the higher frequencies. The intonation of the voice was steady. The analysis of formants of the vowels "a" and "i" showed that the fourth formant of the vowel "i" was lower in frequency postoperatively.

Follow-Up Studies↗
PubMed2001

[Oncocytic neoplasms of the parotid gland. Differential diagnosis, clinical course and review of the literature].

BACKGROUND AND OBJECTIVE: Oncocytic neoplasms of the salivary glands are rare. PATIENTS/METHODS: We report on seven cases of oncocytic neoplasms of the parotid gland (one multifocal nodular oncocytic hyperplasia, five oncocytomas, and one oncocytic carcinoma). RESULTS: While the history, clinical presentation, and histology of all oncocytic neoplasms showed no characteristic differences, intraoperatively the well-differentiated oncocytic carcinoma displayed an infiltrative, locally aggressive growth pattern. A local carcinoma recurring 7 years later corresponded to the primary tumor. There were no metastases. Immunohistochemistry revealed that all oncocytic neoplasms were positive for markers of cytokeratins (KI-1) and negative for markers of carcinoembryonal antigen (CEA), S-100 protein, and smooth muscle actin (SMA). In contrast to the benign neoplasms, the oncocytic carcinoma showed an increased rate of proliferating cells (MIB-1) and a strongly positive reaction with the antibody MA-903 against high molecular weight cytokeratins. CONCLUSIONS: In a review of the literature, we could identify a group of locally aggressive, low-grade oncocytic carcinomas with a considerably better prognosis, similar to that of our case. The therapeutic significance of these findings is discussed.

Adenoma, Oxyphilic↗
PubMed2001

[Differential perilymph fistula diagnosis].

If sudden unilateral deafness accompanied by vertigo and spontaneous nystagmus on the afflicted side occurs during birth, a perilymph fistula with rupture of the round window membrane caused by pressure has to be considered. A 35-year-old pregnant patient was presented with the aforementioned symptoms on the day she gave birth to triplets. During examination, surditas and a paranasal hyposensitivity were found on the right side. Furthermore, a spontaneous nystagmus on the affected side occurred which was not suppressed by fixation. The nystagmus was apparent as a direction-fixed gaze nystagmus. Saccades during smooth pursuit testing as well as a lack of the auriculofacial reflex during contralateral stimulation of the deaf ear could be observed. Magnetic resonance imaging (MRI) of the skull revealed a fresh hemorrhagic cavernoma of the cerebellar pedunculi. This rare lesion caused a nerve compression of the fifth and eighth cranial nerve due to perifocal edema. Neurosurgical intervention was not necessary because of subsequent spontaneous resorption of the lesions and abatement of the deafness within a few days.

Adult↗