Biomedical subjects
Publications and source records attributed to W Mann.
We present the technique to gain free calvarian split bone grafts for reconstruction of the anterior wall of the frontal sinus. The indication for surgery, the surgical technique and the results in 12 patients are discussed.
The addition of 10 mM CaCl2 to glutaraldehyde fixative leads to the formation of small electron-dense deposits in the organ of Corti of the guinea-pig. These precipitates are mainly attached to cell membranes in contact with different extracellular lymphatic fluids. A higher number of precipitates is localized in the acellular parts of tectorial and basilar membrane. Electron energy-loss spectroscopy (EELS) was used to determine the elemental composition of the deposits formed. The spectra showed a prominent signal at the Ca2+ L2,3 ionization edge. Oxygen could also be detected in all the precipitates analysed. EELS analysis of mitochondria of the inner and outer hair cells after conventional fixation (glutaraldehyde followed by post-fixation in OsO4) revealed a small but significant calcium signal.
Thirty-six patients underwent biopsy of clinically suspicious lesions of the mucosa of the upper aerodigestive tract. The biopsy material was evaluated histologically and cytologic smears out of the same lesion underwent quantitative DNA analysis using a numerical index derived from the single cell DNA content. In 30 patients, histologically diagnosed squamous cell cancer was confirmed by DNA analysis with the malignancy grade correlating with the morphologic differentiation of the tumor. Six lesions were histologically benign: i.e. dysplasia (n = 3), hyperplasia (n = 2) and chronic inflammation (n = 1). DNA analysis confirmed the benign nature in 4 cases, but in 2 cases of dysplasia, a diagnosis of malignancy was made. From these results, there appears to be an excellent correlation between DNA analysis and the histologic diagnosis of malignancy. It remains to be proven if this technique of DNA analysis will prove to be a more accurate determinant of malignant potential in premalignant conditions and a method to determine aggressiveness of behavior. An added advantage is that this technique can be performed on cytologic smears, without the need for incisional biopsy.
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The aim of this study was to detect changes of transient evoked otoacoustic emissions (TEOAE) during chemotherapy with cisplatin and fluorouracil (5FU). A review of the literature reveals that the incidence of cisplatin ototoxicity varies from 9% to 50%; this variation is due to differences in doses, duration of administration, to the criteria for ototoxicity and on audiological methods. Three cycles of chemotherapy (1000 mg/m2 5FU from day 1 to 5 and 100 mg/m2 cisplatin on day 1) were given to 12 patients; the OAE were measured before chemotherapy and after each administration. In 86% of the ears measured we found changes in the TEOAE; the mean values for the amplitude of the TEOAE decreased about 13% after the end of the chemotherapy. Pure tone thresholds were reduced in almost 50% of the measured ears. The decrease of amplitude of TEOAE is an early sign of an ototoxic secondary effect, probably due to damage to the outer hair cells. TEOAE is a sensitive method for detecting ototoxicity in cisplatin-treated patients and more reliable than pure-tone audiometry or evoked acoustic potentials.
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Five guinea pigs were exposed to an interrupted 90 dB SPL pure tone of 3.2 kHz for a total application time of 5 min. Following sound application all animals were decapitated and the cochleae were removed. After that, calcium-binding sites were located by the potassium pyroantimonate precipitation method. Another three animals served as control animals and did not receive the sound treatment. Findings confirmed previous studies showing the spatial arrangements of precipitate rich regions in the inner ear's two acellular structures (the basilar membrane and tectorial membrane) and the two cellular structures (the inner hair cells and Huschke's teeth). By using semiquantitative evaluation we found a relative diminution of precipitable calcium in inner hair cells and in Huschke's teeth of sound-exposed animals when compared to untreated animals.
In a retrospective study 256 cases with curative or prophylactic neck dissection were evaluated with regard to neck recurrence and survival. In 173 cases the spinal accessory nerve had been preserved, in the remaining 86 cases it had been sacrificed. The results demonstrate that preservation of the accessory nerve has no influence on the regional recurrence rate and on survival if preservation of the nerve is possible without compromising the radicality of the neck dissection and if the patient is subjected to post-operative radiation.
Jugular foramen tumors involve a critical area of the skull base. Usually they are characterized by palsy of the ninth, tenth, and eleventh cranial nerves. Depending on the extent of the tumor there are various approaches to the skull base and various surgical strategies to preserve the cranial nerves. The study is based on 31 patients who were operated on between 1982 and 1989 at the University ENT and Neurosurgery Departments in Freiburg and Mainz. The neurological findings were analyzed on admission, on discharge, and in the follow-up. While there was partial or complete dysfunction of the lower cranial nerves on discharge, long-term compensation was excellent. All patients were able to breath normally and maintain their weight by oral diet. Rerouting of the facial nerve endangers its postoperative function. Nevertheless, the long-term follow-up demonstrated excellent recovery and good functional and cosmetic results.
Lower cranial neuropathies are a leading presenting symptom in patients with tumors involving the jugular foramen. The purpose of this study is to assess acute and chronic functional deficits along with neurologic findings in 31 patients who underwent resection of a tumor involving the jugular foramen. Preoperative nerve dysfunction made intraoperative preservation unlikely, while postoperative lower cranial nerve dysfunction was found to be transient in many patients. Compensation of permanent dysfunction was usually excellent.
Potassium antimonate was used to precipitate calcium in the cochlea of the guinea-pig. The distribution of the calcium antimonate precipitates was analysed by electron microscopy. The precipitate density was determined in different cell types in the organ of Corti by counting the number of calcium binding sites in a 10-micron 2 area. The size of the precipitates varied considerably, and thus the relative amount of the precipitable calcium was estimated only semi-quantitatively. As the prominent carbon signal is superimposed over the nearby small Ca(2+)-edge signals, the combined signal of the antimony M4,5-edge and the oxygen K-edge of the calcium antimonate salt formed was chosen for the semi-quantitative estimation. Images of the inelastically scattered electrons of the precipitates at delta E = 570 eV were recorded by electron spectroscopic imaging. The area covered by the calcium precipitates within a given cell type was determined in different ultrathin sections of the same organ of Corti by an image processing system.
A new endonasal microsurgical technique for decompression after traumatic optic neuropathy is presented. Compared to the external transethmoidal, the transfrontal or the pterional approach, the main benefit of this method is the superb stereoscopic vision of the medial aspect of the optic canal. The nerve is approached from a 60 degree to 90 degree angle and continuous suction irrigation allows for safe removal of the bony shell. This surgery is done via the endonasal route and therefore has fewer serious complications compared to intracranial, extradural or intradural approaches. Additional trauma due to retraction of the brain is avoided. The anterior ethmoidal cells and the nasofrontal duct remain untouched, avoiding late mucocele formation.
The historical review of submucous septal surgery includes the German pioneers Hartmann (1882) and Petersen (1883), Krieg (1886) and Killian (1899) who finally refined this operation. Besides his technical notes and the development of new instruments Killian defined indications and contraindications for this type of surgery which are considered valid even today.
Cations were precipitated with potassium-pyroantimonate in the middle ear mucosa of the rat and the distribution of the formed precipitates was studied by electron microscopy. The precipitate density in various cells of the different epithelia of the middle ear mucosa was determined on electron micrographs by counting the number of precipitates per unit area. Electron spectroscopic imaging was also performed to obtain information about the spatial distribution of the precipitates and their elemental composition.
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The ciliary activity of the guinea pig tracheal respiratory epithelium was measured using a photoelectric device. Fourteen animals were administered 75 mg diltiazem/kg body weight 2 days, 1 day and 4 h prior to the investigation. Thirteen animals served as controls. In the pretreated group, the mean ciliary stroke frequency (13.4 +/- 3.0 Hz) was significantly lower (P = 0.02) than in the control group (16.6 +/- 3.7 Hz). The application of aerosolized 0.3 mmol/l nifedipine solution on the tracheal preparations of the control animals also significantly reduced the stroke frequency (P = 0.02). The ciliary activity never dropped beyond a frequency of about 8 Hz. The most probable interpretation of these results is a modulating effect of Ca2+ antagonists on ciliary activity by blocking voltage-gated calcium channels.
The present study further examined the in vitro response of human mononuclear cells (MNC) to the Sarcocystis gigantea lectin (SGL). The results confirm our previous report that SGL is mitogenic for human MNC. We now report that SGL is not only a potent mitogen but also a polyclonal activator for human peripheral B cells. As was true for pokeweed mitogen (PWM, 2 micrograms/ml), the addition of SGL (25 micrograms protein/ml) to cultures of MNC caused lymphocyte proliferation and B-cell maturation, indicated by a marked increase in IgG and IgM production. As measured by the [3H]-thymidine incorporation assay, SGL induced significantly higher proliferative responses than PWM (P less than 0.01, n = 24). The values obtained by SGL and PWM for IgG and IgM synthesis were essentially identical. As opposed to SGL, the sarcotoxin-containing fraction (SGTF) did not induce antibody formation or proliferative responses in human MNC.