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Biomedical subjects

F Hoppe

Publications and source records attributed to F Hoppe.

At least 37 records · Page 2Linked to original sources
PubMed2000

Detection of pharyngeal perforation: comparison of aqueous and barium-containing contrast agents.

OBJECTIVE: We sought to assess the value of aqueous and barium-containing contrast agents in the detection of pharyngeal perforation. SUBJECTS AND METHODS: Visual and objective in vitro comparisons of an iodinated aqueous contrast agent, a 50% weight/volume barium suspension, and a 100% weight/volume barium suspension were performed. Moreover, to exclude pharyngeal perforation after surgery, we prospectively examined 109 patients by pharyngography, using the aqueous contrast agent and the 100% weight/volume barium suspension. All patients with a pharyngeal perforation were followed up clinically to exclude complications due to barium application. RESULTS: As opposed to the 100% weight/volume barium suspension, in vitro comparison between the aqueous contrast agent and the 50% weight/volume barium suspension yielded no substantial differences. Seventeen perforations could be detected with the aqueous contrast agent. Although 10 of 17 perforations could be slightly better visualized with the 100% weight/volume barium suspension, two perforations were missed with this agent. Five perforations were equally well detected with both. CONCLUSION: Because of a higher radiopacity, 100% weight/volume barium suspensions may more sharply delineate perforations. However, in contrast to aqueous contrast media, narrow pharyngeal perforations can be missed. Thus, the use of a 100% weight/volume barium suspension does not improve the detection of pharyngeal perforation.

Adult↗
PubMed1999

Current value of double-contrast pharyngography and of computed tomography for the detection and for staging of hypopharyngeal, oropharyngeal and supraglottic tumors.

In light of recent endoscopic techniques the current value of double-contrast pharyngography (DCP) and of CT for detection and staging of hypo-, oropharyngeal, and supraglottic tumors is evaluated. The DCP of 151 patients and CT obtained from 99 of these patients were retrospectively analyzed in a double-blinded manner. We used a standard protocol which comprised all relevant anatomical subregions. Results were compared with direct microlaryngoscopy (DL), indirect laryngoscopy (IL), and post-operative histopathological findings. Sensitivity and specificity of DCP was 75.0 % and 86.7 %, respectively. The DCP and IL techniques together yielded a higher sensitivity (96.7 %) than each method separately. Sensitivity and specificity of CT was 87.5 and 100 %, respectively. In 74.7 % CT provided correct staging. Subregional analysis revealed that the results of DCP and CT depend highly on the localization of the tumor. Our results indicate that DCP represents an important screening method for diagnosing hypo-, oropharyngeal, and supraglottic tumors to complete IL and DL. We show that CT is a reliable method for preoperative staging, although small superficial tumors may occasionally be missed by this method.

Administration, Oral↗
PubMed1999

Proteolytic patterns of head and neck squamous cell carcinoma.

The significance of plasminogen activators and matrix metalloproteases for clinical outcome, growth and metastatic behavior of head and neck squamous cell carcinoma (SCC) is still controversial. The majority of studies has been based on either immunohistological stainings, which provide only limited quantitative information, or in vitro experiments. We analyzed 44 head and neck SCC and 11 mucosa tissue samples for the expression of gelatinolytic or fibrinolytic proteases by quantitative zymographic analysis and compared lytic activities to clinical and histopathological data. We calculated activation ratios for matrix metalloproteinases-2 and -9 (MMP-2 and MMP-9) by separate evaluations of inactive and activated MMP forms. Increased gelatinolytic and fibrinolytic activity was found in head and neck SCC when compared to mucosa. Increased values were caused by MMP-9 and urokinase type plasminogen activator, respectively. No statistically significant correlations of either protease lytic activity or activation ratio could be related to T-stage, metastasis, tissue necrosis or the differentiation stage of tumors. The data recorded are compared with previously published reports.

Carcinoma, Squamous Cell↗
PubMed1999

Free-flap reconstruction for laryngeal preservation after partial laryngectomy in patients with extended tumors of the oropharynx and hypopharynx.

Partial laryngeal resection often results in major aspiration problems, making larynx preservation during surgical removal of tumors of the oropharynx and hypopharynx impossible. However, free flaps can be used to reconstruct perilaryngeal tissue, thus preserving the larynx and ensuring a better quality of life for patients. We present the results of forearm free-flap reconstruction of the supraglottis in 22 patients who underwent resections of extended squamous cell carcinomas of the oropharynx and hypopharynx. A total of 9 patients had T3 lesions and 13 had T4 lesions. All patients were additionally treated with radiation therapy alone (to 70 Gy) or in combination with chemotherapy (Cisplatin; 5-fluorouracil). The mean follow-up was 2.4 years. In four patients, tracheostomy could be closed. Five patients suffered from severe aspiration, one of whom had to undergo a laryngectomy. Six patients had mild aspiration and 7 patients had no aspiration, but extensive edema made decanulation impossible. A total of 13 patients were free of disease, 4 patients died of disease, 1 patient died as the result of a second primary cancer and 1 patient died of other causes. Three patients are alive with persistent tumor. Although the majority of patients experienced a better quality of life as a result of larynx preservation, aspiration has remained a problem following treatment.

Adult↗
PubMed1999

[Outcome after resection of extensive oropharyngeal carcinomas and defect coverage by microvascular anastomosis of a radialis flap].

BACKGROUND: Extensive tumors of the oropharynx require an open approach and plastic reconstruction for good oncologic and functional results. PATIENTS AND METHODS: From January 1988 through December 1996 at the Department of Otolaryngology, Head and Neck Surgery, of the University of Würzburg, 62 patients with extensive tumors of the oropharynx underwent surgical treatment (T2 = 6, T3 = 24, T4 = 32). In 40 patients, the resection was performed via a median mandibulotomy approach, in 22 patients using a lateral pharyngotomy. All patients underwent postoperative radiotherapy up to 70 Gy. RESULTS: Using the Kaplan-Meier method, the five-year survival was 80% for T2, 52% for T3, and 22% for T4. Four patients (7%) presented with a second primary carcinoma, and one also had a third carcinoma. Seven patients who died of T3- and T4-tumors had distant metastases, among them 5 patients who were free of local disease. A regular oral diet was possible on average 14 days postoperatively. All patients underwent tracheostomy. Ninety percent of them were decanulated one year postoperatively. CONCLUSIONS: Resection of extensive carcinomas of the oropharynx and microvascular reconstruction produces good oncological and functional results. The best access to extensive tumors is provided by a mandibulotomy. The advantage of this excellent approach outweighs an increasing morbidity in occasional cases.

Combined Modality Therapy↗
PubMed1999

Increased levels of urokinase receptor in plasma of head and neck squamous cell carcinoma patients.

Urokinase-type plasminogen activator (uPA) is important for matrix degradation and motility of cancer cells. The binding of uPA to its cell surface receptor on cancer cells is essential for effective invasion. A soluble form of urokinase receptor (suPAR) has been described in serum and ascites of ovarian cancer patients and in plasma samples of non-small cell lung cancer patients. Plasma samples from 36 head and neck squamous cell carcinoma patients and 24 healthy control persons were analysed for the presence of suPAR using enzyme-linked immunosorbent assay (ELISA) and the expression levels were correlated with clinical and histopathological data. Significantly elevated levels of suPAR in blood plasma from head and neck cancer patients were observed (p = 0.000), and the suPAR plasma levels decreased after resection of the carcinoma in 8 of 11 patients. suPAR plasma levels of cancer patients showed no significant correlations with T staging, metastasis, recurrence or differentiation stage of the tumours. The significance of suPAR plasma levels in head and neck squamous cell carcinoma patients for prognosis of the disease is discussed.

Adult↗
PubMed1998

[Indications and risks of manual lymph drainage in head-neck tumors].

BACKGROUND: Secondary lymphedema of the head and neck can develop as a result of obstruction of lymphatic channels following the surgical removal of lymph nodes and fibrosis due to irradiation. This can be treated with manual lymphatic drainage. An increase of tumor recurrence due to this therapy is at controversial discussion. PATIENTS: In a retrospective study 191 patients treated for head and neck cancer were questioned on occurrence of lymphedema and therapy with manual lymphatic drainage. RESULTS: 100 patients had received lymphatic drainage, whereas 91 patients belonged to the group without lymphatic drainage therapy. In 37 cases a tumor recurrence or local metastases were reported, 18 of whom had received lymphatic drainage and 19 belonged to the control group. Among these 37 patients neither the group with lymphatic drainage nor the control group differed significantly concerning stage of cancer, histopathological grading, the in sano/non in sano resection of the primary tumor and a lymphangiosis carcinomatosa. An increased recurrence rate among patients who underwent a lymphatic drainage therapy could not be found. CONCLUSION: A lymphatic drainage therapy for patients presenting with lymphedema after the oncological therapy does not increase the rate of local recurrencies. Moreover it improves the quality of life after the cancer therapy. As only few data are available for cases with non in sano surgery and tumors with lymphangiosis carcinomatosa these cases should be excluded from a lymphatic drainage therapy. A spreading of occult tumor cells in these patients might be possible.

Carcinoma, Squamous Cell↗
PubMed1998

Cytotoxic and genotoxic effects of paclitaxel (Taxol) and radiation in a squamous cell carcinoma cell line of the larynx.

Paclitaxel (Taxol) is an antimicrotubular agent which blocks the cells in the G2/M phase of the cell cycle. Because of this mechanism it is presumed that this drug could function as a radiation sensitizer. The cytotoxic and genotoxic effects of paclitaxel and a combination of paclitaxel and radiation were studied in the human laryngeal carcinoma cell line HLac 79. The growth of the cells was significantly reduced at concentrations of paclitaxel as low as 10 nM. Flow cytometry data showed a G2/M block after exposure to paclitaxel. Radiation at 12 and 24 h after drug treatment exerted an additive but no radiation sensitizing effect. As genotoxic effect paclitaxel induced multinucleated cells, possibly in a synergistic manner, at low concentrations (10 nM) and radiation doses up to 3 Gy.

Antineoplastic Agents, Phytogenic↗
PubMed1996

[Morphologic studies of autologous and homologous ossicles after long-term implantation].

BACKGROUND: Although ossicular bone implants have been used to restore the middle ear sound conduction mechanism for more than 30 years, controversy still exists regarding their morphology after long-term implantation. METHODS: Fifty-seven ossicular implants that had been in the middle ear for a mean duration of 12 years (ranged from 3-33 years) were removed at the time of revision surgery and prepared for histological study by light microscopy. These revision operations were performed because of failure to control the disease and/or persistent or recurring hearing loss. Each ossicle was examined for the presence of living bone, extended bone resorption, and inflammatory cells. The findings were correlated to origin, duration of implantation, and the reason for revision surgery. RESULTS: More than a half of the specimens with cholesteatoma and chronic otitis media as reasons for revision surgery showed extended bone resorption and inflammatory cells. Even in clinically uninfected ears, inflammation and bone resorption could be observed. Lymphocytic infiltration as an inflammatory pathologic change predominates in autologous implants. CONCLUSIONS: On the basis of these histological observations, we conclude that autologous ossicles from cholesteatoma should not be used in reconstructive middle ear surgery. Furthermore, the use of ossicular implants after revision surgery should be avoided.

Bone Resorption↗
PubMed1995

[Detection of DNA of human papillomaviruses (HPV) in an "aggressively" growing cholesteatoma. Is cholesteatoma a virus-induced tumor?].

It is yet unknown why under certain circumstances the benign epithelium covering the outer ear canal in a protective role causes an erosion of bony structures after migration into the middle ear. Histologically, a papillomatous growth and clusters of koilocytes are typical features of the aggressively growing, bone-destructive areas of the cholesteatoma. Since these resemble the characteristics of a papilloma, biopsies originating from cholesteatomas were examined for the presence of human papillomavirus (HPV) DNA. Findings demonstrated that HPV-11-related DNA was present in one such lesion. In general, papilloma viruses need specific conditions to be able to replicate and induce a papillomatous growth. Retraction pockets of epithelium, junction lines between squamous epithelium and mucosa as well as inflammatory processes may stimulate this replication. Because these conditions are characteristic for cholesteatoma, we therefore suggest a possible papillomavirus etiology for the development of aggressive cholesteatoma.

Biopsy↗
PubMed1995

[Proliferation behavior of cholesteatoma].

Two types of growth can be observed clinically in cholesteatoma: an aggressive and a less aggressive type. In this study monoclonal antibodies to Ki-67 proliferation antigen, epidermal growth-related factor (EGFR) and collagen type IV were used to examine cholesteatoma specimens from 36 patients undergoing tympanomastoid surgery. Mitotic cells were found in various amounts in each sample and an increase was seen in tissue folds and recesses. No difference was observed between the aggressive and less aggressive types. The expression of EGFR was restricted to basal and suprabasal layers and showed no differences between the groups. Small defects of the basal membrane were seen frequently and reflected the invasive growth potential of the cholesteatoma epithelium. These results showed that clinically less aggressive cholesteatomas also have a high proliferation rate. As a consequence, leaving small rests of epithelium in situ during middle ear surgery increases the risk for recurrences. Morphologically, no differences could be observed between an aggressive and a less aggressive cholesteatoma.

Basement Membrane↗
PubMed1994

Human-papillomavirus DNA in cholesteatomas.

Cholesteatoma of the middle ear is a relatively common disorder, often with severe consequences. Histologically, the aggressively growing, bone-destructing form shows papillary growth and koilocytosis, which are characteristic of papillomavirus-induced lesions. A PCR (polymerase chain reaction) method using degenerate primers for the detection of any known or as yet unknown HPV (human papillomavirus) type was applied in screening 51 biopsies from 42 patients. A resulting 36% (16/45) of the cholesteatomas were found to contain papillomavirus DNA, which hybridized under stringent conditions with an HPV-II DNA probe. In 3 cases the presence of HPV-II DNA could be confirmed by sequencing the PCR products. The mere presence of this HPV DNA does not prove an etiological role of this group of viruses in the induction of cholesteatomas. It does, however, identify another group of human proliferative lesions putatively linked to papillomavirus infections.

Adolescent↗
PubMed1994

[Is reuse of autologous ear ossicles in cholesteatoma or chronic suppurative otitis media justified?].

From the 1950s onwards ossicular bone autografts have been used to restore the middle ear sound conduction mechanism. Controversy still exists regarding the appropriateness of autologous ossicular bone grafts in chronic middle ear diseases. This communication is based on a study of 149 ossicles surgically removed from 120 patients with different ear diseases, at the Department of Otolaryngology, Head and Neck Surgery of the University of Wuerzburg. It is the object of this study to systematically investigate the histological findings in the ossicles in cholesteatoma and chronic suppurative otitis media, and also to try to assess their significance. For comparison the ossicles of traumatic subluxation and otosclerosis are also included in our material. In about one-fourth of the incidences of cholesteatoma, squamous epithelium is found adherent to the ossicles with subepithelial connective tissue of varying thickness separating the matrix from the involved ossicle so that the matrix is never in direct contact with the underlying bone. Osteomyelitis is shown in both groups. Bone resorption predominates in the complicated metaplastic process due to the action of osteoclasts irrespective of the cholesteatoma group or the chronic otitis media group. Bone erosion is evident not only on the surface of the ossicles but also in the bone. On the other hand, ossicles in the groups of traumatic subluxation and otosclerosis remain histologically normal without evidence of pathologic changes. On the basis of these histological observations and on account of the high probability of adherent squamous epithelium in our opinion autologous ossicles from cholesteatoma and chronic suppurative otitis media should not be used in reconstructive middle ear surgery.

Adolescent↗
PubMed1994

Juvenile nasopharyngeal fibroma: androgen receptors and their significance for tumor growth.

Since the publications of Martin, et al. (1948) and Schiff (1959), who were the first to report on the administration of sex hormones to juvenile nasopharyngeal fibroma (JNF) patients, several authors have described the different clinical effects and histologic changes after androgen and estrogen application. Since the mechanism of action of sex steroids in juvenile nasopharyngeal fibroma is almost unknown, the authors have studied androgen receptor binding in cultured tumor fibroblasts from three patients with JNF. Maximum androgen binding (Bmax) of the tumor fibroblasts approximated to that of genital skin fibroblasts, which served as a control androgen target tissue with high receptor density. Furthermore, in vitro experiments showed that the growth rate of tumor fibroblasts increased when testosterone was added to the culture medium, while the addition of two antiandrogens, cyproterone and flutamide, caused a reduction in growth rate. It is concluded from these results that JNF is a hormone-dependent tumor stimulated by testosterone whose growth rate may, at least in vitro, be reduced by antiandrogens such as cyproterone and flutamide.

Cell Division↗
PubMed1990

Characterization of a protein with an acetylcholine receptor epitope from myasthenia gravis-associated thymomas.

Immunohistochemical studies have shown that almost all thymomas of myasthenia gravis patients contain at least one protein sharing an antigenic determinant with the nicotinic acetylcholine receptor (AchR) of human muscle. We describe the characterization of this protein (p153) which has a molecular weight of 153 and an isoelectric point of 5.0. By treatment of p153 with endoglycosidases, no significant glycosylation has been detected. Immunologically, p153 crossreacts with monoclonal antibodies against the amino acid sequence 371-378 of the alpha-chain of the AchR. No cross-reactivity to the main immunogenic region of the AchR nor an alpha-bungarotoxin binding site are found. By Western blotting, p153 was generally neither detectable in normal tissues nor extrathymic tumors with the exception of paraganglioma and neuroblastoma. In conclusion, the structure of p153 is apparently unrelated to the AchR from muscle or the alpha-bungarotoxin binding proteins from thymoma. Since there is no evidence for an AchR expression in thymoma, the antigenic homology of p153 with the nicotinic AchR might be relevant for triggering an intrathymomatous autosensitization of maturing T cells and could be responsible for the high association of thymomas with myasthenia gravis.

Antibodies, Monoclonal↗
PubMed1989

Proliferation-associated expression of DNA methyltransferase in human embryonic lung cells.

The cell cycle-dependent and proliferation-associated expression of the enzyme DNA methyltransferase has been evaluated immunocytochemically in synchronized L-132 human embryonic lung cells, using the anti-DNA methyltransferase monoclonal antibody M1F6D7/5C10. DNA methyltransferase-reactivity was firstly seen in mid-G1 cells. An intense and granular reaction in the cell nuclei with a sparing of the nucleoli was observed in addition to a homogenous and faint cytoplasmic staining. The staining intensity in the cell nuclei increased progressively up to mitosis. In early mitotic cells an intense perichromosomal staining was observed in addition to a homogenous staining of cyto- and karyoplasm after the resolving of the core membrane. In late mitosis the staining intensity decreased rapidly. Early G1 cells and density inhibited, resting G0 cells showed no DNA methyltransferase reactivity at all. Our results indicate that anti-DNA methyltransferase monoclonal antibodies could become valuable tools to detect proliferating cells in cell cultures and tissues.

Cell Cycle↗
PubMed1989

Proteins with epitopes of the acetylcholine receptor in epithelial cell cultures of thymomas in myasthenia gravis.

Thymomas from 12 patients with myasthenia gravis (MG) were investigated for the presence of epitopes of the alpha-subunit of the nicotinic acetylcholine receptor (AchR) using monoclonal antibodies (MAb) reacting against the AchR. In all but two of the tumors epitopes corresponding to antigenic determinants located on the cytoplasmic side of the AchR were identified. From eight thymomas cell lines were established that have been kept in culture for up to 6 months. The cultured cells expressed the same AchR-epitopes as did the primary tumors. During early passages the percentage of epithelial cells positive for the AchR epitopes approximately mirrored the percentage of positive cells in the original tumors. With passaging the relative number of positive cells usually declined but in some cultures an increase was observed. Three cell lines that showed extensive staining with an MAb against the AchR were radiolabeled to characterize the antigen. From protein extracts of these three cell lines proteins of 45 kd and 156 kd molecular weight (MW) were precipitated. These proteins are different from other proteins described in the context of both thymomas and MG. The negative reactivity with MAb against other epitopes of the alpha-subunit, especially against the main immunogenic region (MIR), speaks in favor of membrane-associated proteins of only limited crossreactivity to the AchR. A previous study found an almost exclusive occurrence of these AchR-epitopes in thymomas associated with MG, but not in other thymomas of similar histologic type. The expression of the proteins described here could therefore play a role in the triggering of the autoimmune process against the AchR of the motor, endplate in MG patients.

Adult↗