PubMed Health⌕ Search

Biomedical subjects

M Streppel

Publications and source records attributed to M Streppel.

At least 55 records · Page 3Linked to original sources
PubMed1998

Significance of trigeminal sensory input on regrowth of hypoglossal and facial motoneurons after hypoglossal facial anastomosis in rats.

Hypoglossal facial anastomosis (HFA) is a standard surgical technique for restoration of facial movements in cases of intratemporal lesions of the facial nerve. Case reports provide evidence that an affected trigeminal system reduces functional outcome. In order to detect morphological changes in the hypoglossal nucleus responsible for this phenomenon, we used 18 Wistar rats and performed three different surgical combinations. In group 1, six animals received HFA only. In group 2, HFA was combined with resection of the contralateral infraorbital nerve. In group 3, HFA was combined with resection of the ipsilateral infraorbital nerve. Fifty-six days after the operation, horseradish peroxidase (HRP) was injected into the whisker pad. As shown in previous studies using HRP, retrograde-labelled motoneurons occurred in the hypoglossal and facial nuclei. Counts of the labelled motoneurons showed no change in the number of projecting hypoglossal motoneurons in group 2 when compared to HFA only, but a significantly smaller number in group 3 (-35%). Furthermore, the number of projecting facial motoneurons was significantly reduced in group 2 (-85%) and group 3 (-45%). These morphological findings indicate an absent or insufficient functional connection between the contralateral infraorbital nerve and the hypoglossal nucleus, and a strong influence of the infraorbital nerve to the ipsi- and contralateral facial nuclei. Additionally, our study provides morphological evidence that the integrity of the sensory trigeminal system is very important in reconstructive facial nerve surgery.

Analysis of Variance↗
PubMed1998

Variability of repeated facial nerve electroneurography in healthy subjects.

BACKGROUND: Facial electroneurography is an objective measurement of a muscle compound action potential. The amplitude ratio between the paretic and the normal side is used as a basis for estimating the prognosis of facial palsy. According to Esslen, the difference of amplitudes in healthy subjects is only 3%. Twenty healthy test persons were investigated with the aim of 1. reproducing the published data on the left-right difference in normal test subjects and 2. determining whether the amplitude ratio is constant over time after repeated measurements. STUDY DESIGN: Bilateral electroneurography was conducted on 20 healthy volunteers (age range, 23-36 y; 12 men, eight women). Two investigators performed four measurements at 1-week intervals on every subject. RESULTS: Mean amplitude ratio was 32.5%. Repeated measurements on the same individual differed considerably-- from 0% to 80%. The 99% confidence interval computed from the data ranged from 26% to 39% amplitude ratio. CONCLUSION: The symmetry of facial evoked compound potentials postulated by Esslen and Fisch is not supported by these data. As have other investigators, the authors found significant left-right differences in healthy subjects. Furthermore, they showed for the first time that the amplitude ratio is not constant in every individual at repeated measurements. In light of these data, prognosis of facial palsy based on electroneurographic data alone seems doubtful.

Adult↗
PubMed1998

Altered expression of immune-related antigens by neuronophages does not improve neuronal survival after severe lesion of the facial nerve in rats.

Injection of Fluoro-Gold (FG) into the whiskerpad muscles of rats yields a permanent retrograde labeling of motoneurons in the facial nucleus. Following subsequent resection of 10 mm of the facial nerve, one-third of the facial motoneurons die and the microglia phagocytize the dead FG-labeled neurons, take up FG, and get labeled in vivo. The resulting identification of all FG-labeled cells allows long-term comparative investigations on the behavior of neuronophages. In this study, we used two groups of rats to test whether the quantified expression of five immune-related antigens by neuronophages was related to quantified decline in neuron number (counts after immunostaining for neuron-specific enolase) 3 to 224 days after resection of the facial nerve. Rats of the first group received standard food and those of the second group, pellets containing 1,000 ppm of the calcium channel blocker nimodipine. Image analysis of the number of FG-containing cells and the number and projection area of immunopositive neuronophages in serial sections for each antigen showed that nimodipine significantly attenuated the immunostaining for CR3, MHC class I, and class II antigens (monoclonal antibodies [MAbs] OX-42, OX-18, and OX-6); enhanced the expression of monocyte-macrophage-specific antigen (MAb ED1); and did not change the expression of rat macrophage differentiation antigen (MAb ED2). The altered expressions, however, had no effect on the loss of motoneurons in the lesioned facial nucleus. We conclude that the degree of expression of immune-related antigens by neuronophages has no influence on the delayed neuronal cell death induced by permanent target deprivation.

Animals↗
PubMed1997

[Effectiveness of partial and complete instrumental masking in chronic tinnitus. Studies with reference to retraining therapy].

Jastreboff und Hazell [9] developed a neurophysiological approach to tinnitus perception, including the important role of the central nervous system in the maintenance and intrusiveness of tinnitus. They introduced tinnitus-retraining therapy, consisting of four different strategies: (1) directive and person-centered counseling; (2) hearing aids and/or noise generators and/or environmental sounds; (3) psychological therapy; (4) adjacent therapies. Tinnitus should not be masked as with a tinnitus-masker, but must be able to be heard in addition to the noise! A noise generator or hearing aid should be worn at least 6-8 h per day over a period of up to 18 months. In additions several clinical visits are required in order to reinforce the counseling. The actual results show complete tinnitus remission for about 20-30% and partial remission for 50-60% of the patients [6]. We report on a retrospective study in patients wearing hearing aids or tinnitus-maskers over a period of 3 years. We compared the results of patients using partial tinnitus masking to those using complete masking. The tinnitus-related and general psychological complaints were acquired by the 52-item tinnitus questionnaire developed by Hallam et al. [4] and modified by Goebel and Hiller [3]. To describe the dimensions of tinnitus-related distress the scales are labelled emotional distress, cognitive distress, emotional and cognitive distress, intrusiveness, auditory perceptual difficulties, sleep disturbance and somatic complaints. Positive changes for the global tinnitus questionnaire score of more than 10 points are significant in the dimensions of tinnitus-related distress and are described as partial tinnitus-reduction. The group with partial masking effects can be compared to those performing retraining therapy to day because directive and personal centered counseling were integrated for all patients. Patients reporting partial masking effects through their aids (hearing aid or noise generator) showed more effective treatment results (reduced or disappeared tinnitus) than those using complete masking effects (P < 0.05). The reported results are improved by current investigations in Germany showing about 20-30% tinnitus remission and 50-60% significant reduction after 1 year of treatment [1]. Further scientific investigations must be carried out to evaluate the appropriateness and effectiveness of the retraining therapy and with regard to unique quality standards.

Cognitive Behavioral Therapy↗
PubMed1997

Axotomy induces transient calbindin D28K immunoreactivity in hypoglossal motoneurons in vivo.

Calbindin D28K, an intracellular calcium-binding protein, acts as Ca2+ buffering system in the cytoplasm. By means of this property, calbindin may protect neurons against large fluctuations in free intracellular Ca2+ and, hence, may prevent cell death. Although axotomy causes a massive influx of calcium into the lesioned neurons, resection of the hypoglossal nerve does not induce extensive neuronal cell death in rats. Even several weeks after axotomy, about 70% of the motoneurons survive despite permanent target deprivation. The mechanisms responsible for this remarkable survival rate are unknown. In this study, we have looked at the modification of calbindin immunoreactivity in axotomized hypoglossal motoneurons. In non-axotomized motoneurons, no calbindin is detectable by immunocytochemistry. Axotomy induced an increase of calbindin immunoreactivity in lesioned motoneurons. This increase, visualised by the number of calbindin-immunoreactive neurons extended from 1 day to 28 days. At this time most, but not all, motoneurons located on the side of the lesion were calbindin-positive as shown by retrograde labeling and immunoquenching. From 14 days post operation, calbindin immunoreactivity decreased and reached its basal value after 35 days post operation. At that time, only fibres were still calbindin immunoreactive. Interestingly, calbindin-immunoreactivity was also increased in almost all cell nuclei, compatible with a nuclear regulation. These data are consistent with the hypothesis that, as a reaction to axotomy, motoneurons trigger an increase in calbindin expression which acts as a compensatory Ca(2+)-buffering system, enabling neurons to maintain Ca2+ homeostasis and the survival of many motoneurons after axotomy.

Animals↗
PubMed1997

[Drug treatment of invasive aspergillosis of the paranasal sinuses].

Aspergillosis belongs to the group of mycotic diseases of the paranasal sinuses. The invasive forms, and particularly the fulminant forms, are potentially fatal. Primary surgical intervention with complete removal of the mycotic mass should be performed. Additionally an antimycotic drug therapy with amphotericin B must be started. In a review of the literature, there is no case surviving an extended invasive aspergillosis after failure of the operative therapy and after failure of the postoperative amphotericin B treatment. We report an interesting case of a complete remission of an invasive, partially fulminant aspergillosis of the paranasal sinuses and frontal and basal regions. After incomplete removal of the mycotic mass by an endo- and extranasal approach, we started postoperative drug therapy with amphotericin B. Under this treatment the mycosis progressed. Additionally the patient developed severe renal side effects requiring suspension of the treatment. At this time, we started a combined antimycotic drug therapy with liposomal amphotericin B (AmBisome) and itraconazol. Within 10 weeks there was complete clinical and radiologic remission. The patient died 63 weeks after this treatment because of a fulminant bacterial pneumonia. Post mortem examination showed no aspergillosis in the skull base, the paranasal sinuses, or in the lung. The question arises as to whether this drug combination of liposomal amphotericin B (AmBisome) and itraconazol is a real alternative to high-risk surgical interventions in this region.

Amphotericin B↗
PubMed1997

[Progressive hearing loss in children with hearing aids].

BACKGROUND: The possibility of hearing aid induced deterioration was first described in 1939 (Berry 1939, Holmgren 1939). Since then numerous studies discussed this problem controversely. However, it is undisputed that in cases of profound sensorineural hearing loss in childhood powerful hearing aids are necessary for maturation and auditory and speech development. An increase of progressive sensorineural hearing loss in the last three years in children with profound sensorineural hearing loss fitted with hearing aids (2 children in 1993, 6 children in 1996) drew our attention to this problem. METHOD: Over a period of four years, we collected the data of 16 children with progressive hearing loss. RESULTS: The comparison of the duration of the hearing aid use since fitting and the maximum output level fail to explain this increase. Moreover our strategy in hearing aid fitting remained unchanged during this period especially with regard to SSPL max. We also performed an analysis of the childhood disorders associated with the sensorineural hearing losses. This analysis provided no further information for the increase of hearing loss. CONCLUSION: There is no evidence that powerful hearing aids damage hearing and induce progressive sensorineural hearing loss in childhood. Therefore we believe that there is no need to change our hearing aid fitting strategy particularly with regard to the maximum output level up to 135 dB SPL measured in situ. The increase in the number of progressive cases in the last two years indicates the necessity of further investigations in this field.

Child↗
PubMed1997

Effect of delayed facial-facial nerve suture on facial nerve regeneration. A horseradish peroxidase tracing study in the rat.

In clinical practice, the lesioned facial nerve is usually restored by facial-facial nerve anastomosis (FFA) with some delay. The optimal time-point for facial nerve reconstruction is still unknown. This study, using rats, compared the effects of immediate and delayed FFA, i.e. FFA 7-56 days after interruption of the facial nerve. Muscle reinnervation was studied 42 days after nerve suture by counting all retrogradely labelled facial motoneurons after injection of horseradish peroxidase (HRP) into the whiskerpad of the rats. Immediate FFA caused a local hyperinnervation of the target muscle, i.e. the projection of more neurons into the whiskerpad muscles than under normal conditions. FFA delayed for 7 days resulted in a significant suppression of this hyperinnervation, whereas longer delay times of 10-56 days showed no difference from immediate FFA.

Analysis of Variance↗
PubMed1997

[No evidence for hearing aid-induced progressive pediatric hearing loss in the Cologne region].

Progressive hearing loss during childhood caused by a hearing-aid induced deterioration has been discussed controversely since 1939. However, it is unchallenged that in cases of profound sensorineural hearing loss in infancy and early childhood powerful hearing aids are necessary for auditory and speech development. Due to an increase of progressive hearing losses during the last 4 years, we discussed the possible causes and the probability of hearing aid induced progressions once more. Our study consists of two investigations: First, all patients since 1993 suffering from progressive hearing loss among all hearing impaired children in the department of Audiology and Pedaudiology of the ENT-Hospital of Cologne were taken into account. Second, all children of the Rheinische school for hearing impaired children were investigated. The evaluated data included the degree of severity and etiology of the hearing loss, the duration of the hearing aids use and the amplification of the hearing aid. 23 children were diagnosed with a progressive hearing loss in the period. We observed a massive increase over these years. No correlation between the duration of the hearing aid usage and the maximum output level was found. Furthermore, there was no difference between the causes of the hearing losses between the children of the school and the children with progressive hearing loss. At the moment, we do not see any reason to change our strategy for fitting hearing aids. The increase of progressive cases in the last 2 years should be the reason for further investigations in this field.

Adolescent↗
PubMed1996

Nimodipine accelerates axonal sprouting after surgical repair of rat facial nerve.

Facial-facial anastomosis (FFA), i.e., suture of transected facial nerve, was performed in adult Wistar rats. For 10-112 d post-operation (DPO), half of the animals received standard food (placebo) and half received food pellets containing 1000 ppm nimodipine, a Ca2+ channel blocker. The time course of mimetic reinnervation between these two groups was compared by counting all retrogradely labeled motoneurons after injection of horseradish peroxidase (HRP) into the whiskerpad. In unoperated animals, injection of HRP labeled 1280 +/- 113 motoneurons. After FFA, this number dropped to zero, and the first HRP-labeled facial motoneurons reappeared in both placebo- and nimodipine-treated animals at 14 DPO. The treatment with nimodipine yielded two beneficial effects. (1) It accelerated axonal sprouting until 28 DPO. Whereas the number of HRP-labeled cells in the placebo group was 171 +/- 9 (mean +/- SD) at 16 DPO, 372 +/- 43 at 21 DPO, and 636 +/- 187 at 28 DPO, the number of sprouted motoneurons in nimodipine-treated rats was twice as high: 386 +/- 34 at 16 DPO, 620 +/- 28 at 21 DPO, and 756 +/- 257 at 28 DPO. (2) Nimodipine reduced the polyneuronal innervation of the target muscles. Whereas the number of HRP-labeled cells in the placebo group increased to 1430 +/- 36 at 56 DPO and 1600 +/- 31 at 112 DPO, the number of labeled motoneurons in nimodipine-treated rats remained almost within the normal range: 1315 +/- 31 at 56 DPO and 1354 +/- 33 at 112 DPO.

Anastomosis, Surgical↗
PubMed1996

ED2-positive perivascular cells act as neuronophages during delayed neuronal loss in the facial nucleus of the rat.

Injection of Fluoro-Gold (FG) into the whisker pad of rats yields a stable retrograde labeling of facial motoneurons. After removal of 10 mm from the facial nerve the microglia phagocytose the FG-prelabeled dead neurons and assume the label. A subsequent brightfield immunostaining of the sections with HRP-DAB as end-product fully quenches the fluorescence of FG from all specifically stained structures (immunoquenching). Combining FG-labeling of neuronophages with immunoquenching, we recently described a population of enigmatic fluorescent cells, found in immediate vicinity to the motoneurons after the general neuronofugal migration of microglia. As the fluorescence of these cells was not quenched after a triple immunostaining with anti neuron-specific enolase, anti-GFAP, and OX-42 (quenching all fluorescence from neurons and glia), they seemed to represent a new, immunologically not identified neuronophage. Now we have further characterized this cell type. Following triple immunostaining, we tested a broad panel of mabs (OX-33, OX-19, OX-18, OX-6, R73, ED1, and ED2) to stain, quench fluorescence, and thus immunotype the unknown phagocytes. Only the mab ED2, the classical marker for perivascular cells, specifically stained the small round neuronophages. This surprising migration of perivascular cells toward decaying neurons was additionally tested and confirmed by intracerebroventricular application of FG prior to resection of the facial nerve Providing evidence for neuronophagia by ED2-positive cells, our results strongly support the hypothesis that the latter are the APC (antigen presenting cells) of the CNS.

Animals↗
PubMed1996

[Interdisciplinary therapeutic concept in severe bacterial infections of the central respiratory tract in childhood].

BACKGROUND: Apart from all advances made in the management of central airway infections, Acute Epiglottitis (AE) and Bacterial Tracheitis (BT) continue to be causes of life-threatening airway obstruction in children. The aim of this retrospective study was to evaluate deficiencies in the diagnostical protocol, to clarify the role of airway endoscopy in acute childhood stridor, and to identify current reasons for fatalities in these diseases. MATERIAL: In the observation period between 1980-92, we found 12 patients suffering from BT and 21 from AE managed in close cooperation of the involved disciplines at the pediatric intensive care unit of the University of Cologne. RESULTS: Laryngoscopy with fiberoptic or small rigid endoscopes allowed in awake cooperative children accurate diagnose of AE, and the exclusion of supraglottic inflammation in BT without complications. Furthermore, additional endoscopic information of the degree of inflammation was helpful in the next critical decision, whether artificial airway or rigid tracheobronchoscopy was required. Nasotracheal intubation was necessary in 76% of our patients, in one child tracheostomy was performed (5%). Premature extubation necessitating reintubation occurred in 33% of the children suffering from BT. In these patients, our method of advancing a flexible endoscope for tracheoscopy through the respiration tube failed because of a low tube diameter. Another remarkable finding was the high mortality in AE (14%). Affected children were admitted in poor post-hypoxia conditions following outdoor cardiorespiratory arrest. CONCLUSION: In the analysis of the clinical course we found three decisive turning points in managing the disorder; First, the confirmation of the correct admission diagnosis; second, the decision, as to whether an artificial airway should be established; and third, the proper time of extubation. The most decisive factor in decreasing mortality seems to be timely, appropriate presentation at referral centers if AE or BT is suspected. Clinically, progressive management of childhood stridor requires close cooperation between the Pediatric, Anesthesiologic, and ENT Departments. Fiberoptic endoscopy as a guide to current airway management is a major step forward and should be a part of every established protocol.

Airway Obstruction↗
PubMed1996

[Hypoglossal nerve paralysis after endonasal paranasal sinus operation in intubation narcosis].

BACKGROUND: In the literature the possibility of a pressure trauma to the hypoglossal nerve between the root of the tongue and the ligamentum stylohyoideum is discussed. A recent in vivo study examined the effects of forced reclination of the head on the nerve. PATIENT: A left sided hypoglossal nerve paralysis occurred in a patient after an endoscopically controlled endonasal operation under general anesthesia with transoral intubation. RESULTS: Clinically and electrophysiologically the palsy seemed to be transient due to neurapraxia. An X-ray of the neck performed after the operation revealed a calcification of the left ligamentum stylohyoideum. All the other diagnostic studies (ultrasound of the neck, neurological examination, serological tests, and CT scan of the head) did not show any abnormalities. This is the first time, that a postoperative hypoglossal nerve palsy has been observed, which could not be explained by extensive stretching or pressure. CONCLUSION: We believe that the short pressure of the Mcintosh spatula produced the hypoglossal nerve palsy described.

Adult↗
PubMed1993

A multicenter comparative study of brodimoprim and amoxicillin therapy in the treatment of tonsillopharyngitis in adults.

STUDY OBJECTIVE: To compare the efficacy and safety of brodimoprim (BDP) with those of amoxicillin (AMX) in patients with acute bacterial pharyngitis/tonsillitis. DESIGN: Randomized controlled study. SETTING: Hospital and general practices in Austria, Germany and Switzerland. PATIENTS: 519 adult patients of both sexes aged 12 to 75 years. INTERVENTION: Patients were allocated to an 8- to 12-day treatment with BDP (400 mg loading dose followed by 200mg once a day) or AMX (750mg t.i.d). MAIN OUTCOME MEASURES: Resolution of clinical signs/symptoms and negative bacterial examination at completion of therapy. RESULTS: Clinical cure/improvement rate of 97.8% and 94.8% in respectively the BDP and the AMX group. Bacterial eradication in 87.7% of the cases treated with BDP and 88.3% of those receiving AMX. Very good/good tolerability in 85.2% BDP- and 82.8% AMX treated patients.

Acute Disease↗
PubMed1990

Selective hearing in the aged with regard to speech perception in quiet and in noise.

Most listening environments contain some noise which is mixed up with the speech. The effects of noise on speech perception depend on the parameters of the noise (long term spectrum, fluctuations of the intensity in time and average intensity relative to the intensity of speech) and on the speech material (sentences, monosyllables, CV-, CVC-, VC-syllables). The most effective at masking are noises with spectra similar to the speech spectrum, such as the speech simulating noise (CCITT-noise) or cocktail-party-noise. The cocktail-party situation is judged to be a difficult communication situation not only by the hearing impaired but also by patients with presbycusis. We examined different age-dependent changes of the speech discrimination in noise ability. Using sentences and CV-syllables (rhyme test) the critical signal-to-noise ratios (S/N-dB) for a speech discrimination of 35%-45% were investigated for monaural and binaural noise representations for different age groups. The results are compared to several types of hearing loss and to those of similar studies in literature. The data of this study prove that hearing impaired and elderly patients are greatly affected by noise. While younger patients with moderate high-tone hearing loss may profit from a special hearing aid device with an integrated noise suppression-system, an improvement of speech discrimination in noise for the elderly can be achieved only by enhancing the signal-to-noise ratio by more than 10 dB. This is possibly because of the reduced capacity for frequency-, intensity- and time-resolution in the peripheral and central pathways of the hearing organ of the aged.

Adult↗