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V Jahnke

Publications and source records attributed to V Jahnke.

At least 37 records · Page 2Linked to original sources
PubMed1998

[Glands of the human nasal mucosa--electron microscopy and immunohistochemical studies].

BACKGROUND: Ultrastructural characteristics of the nasal glands are presented and possible changes concerning different diseases of the nasal mucosa are investigated. METHODS AND PATIENTS: Specimens from 23 patients suffering from primary ciliary dyskinesia, allergic rhinopathy, and chronic inflammatory hyperplasia were the subject of electron microscopic and immunohistochemical studies. RESULTS: All preparations exclusively showed glands of the serous type. The end segments of the glands were surrounded by contractile myoepithelial cells in a basket-like fashion. Distinct differences in the fine structure of the glands were not observed between the individual groups. The epithelial cells of the efferent ducts consisted of numerous rows forming one layer with pronounced interlockings. These cells in particular showed a high content of mitochondria. This segment of the duct probably has the function of changing the content of water and ions in the nasal secretion. CONCLUSIONS: Our immunofluorescence and electronmicroscopic investigations present the ultrastructure of the nasal glands in detail. We assume an influence of the efferent ducts on the composition of the nasal secretion.

Biopsy↗
PubMed1998

Influence of tumour necrosis factor microsatellite polymorphisms on susceptibility to head and neck cancer.

While cigarette smoking and alcohol consumption are recognized covariates for head and neck squamous cell carcinoma (SCC), the role of genetic factors in determining individual susceptibility is unknown. The human tumour necrosis factor (TNF) region on chromosome 6p21 within the major histocompatibility complex (MHC) includes a number of immunologically important genes. Recently, five microsatellite markers have been described in the TNF locus. TNF levels vary with different TNF microsatellite alleles, and associations of these microsatellite markers with autoimmune diseases and different types of cancer have been shown. Therefore, the TNF locus represents candidate susceptibility genes for head and neck cancer. This study describes the influence of TNF a-d microsatellite polymorphisms on susceptibility to head and neck cancer by comparing the allele frequencies of 269 patients suffering from laryngeal cancer and 123 patients suffering from oral cavity pharyngeal cancer and 113 German controls. DNA was extracted from peripheral blood samples, amplified by polymerase chain reaction with fluorescently labelled primers for TNF microsatellite (a-d) and electrophoresed on polyacrylamide gels using an automated DNA sequencer. The data showed no differences in allele frequencies between controls and pharyngeal cancer patients. By contrast, the TNF b3 allele was associated with altered risk for laryngeal cancer (p = 0.0006, odds ratio 2.2). Homozygosity for TNF b3/b3 resulted in an increased risk of developing laryngeal cancer (p = 0.004, odds ratio 5.3). Susceptibility to supraglottic SCC and multiple primary tumours was mediated by the absence of the a11 allele. The data provide the first evidence that allelism at the TNF microsatellite markers alter the risk of developing SCC of the larynx.

Alleles↗
PubMed1998

The glutathione S-transferase GSTP1 polymorphism: effects on susceptibility to oral/pharyngeal and laryngeal carcinomas.

We have examined the hypothesis that the polymorphic, glutathione S-transferase GSTP1 gene is a susceptibility candidate for squamous cell cancer of the oral/pharynx and larynx. We describe GSTP1 genotype frequencies in 380 cases and 180 controls. We found a lower frequency of GSTP1 AA in the oral/pharyngeal cases compared with controls (p = 0.003, odds ratio = 0.47) after correction for age and gender. We used an immunohistochemical approach to show widespread expression of the GSTP1 subunit throughout the pharynx and larynx. In uninfiltrated tissue, strong positivity was found throughout the squamous cell epithelium with the exception of the basal cell layer. The cilia of the respiratory epithelium of the larynx also showed positivity for GSTP1. In tumour tissue, expression of GSTP1 was similar in pharyngeal and laryngeal samples. These data are the first to show that polymorphism at GSTP1 mediates susceptibility to squamous cell cancer of the upper aerodigestive tract. No significant interactions were identified between GSTP1 and GSTM1, GSTM3, GSTT1 and the cytochrome P450 CYP1A1, CYP2D6 and CYP1A1 genotypes.

Alcohol Drinking↗
PubMed1998

Polymorphism in cytochrome P450 CYP2D6, CYP1A1, CYP2E1 and glutathione S-transferase, GSTM1, GSTM3, GSTT1 and susceptibility to tobacco-related cancers: studies in upper aerodigestive tract cancers.

Glutathione S-transferase GSTM1, GSTM3 and GSTT1 and cytochrome P450 CYP2D6, CYP1A1 and CYP2E1 loci are susceptibility candidates for cancers of the upper aerodigestive tract because putatively protective and risk genotypes have been identified from studies in other diseases associated with alcohol and tobacco consumption. We describe genotype frequencies in 398 oral, pharyngeal and laryngeal squamous cell carcinoma patients and 219 control individuals. Of the genotypes presumed to be protective, only GSTM1 A/B influenced susceptibility; the GSTM1 A/B frequency was lower in the patients than the control individuals both before [odds ratio = 0.3, 95% confidence interval (CI) 0.1-0.7] and after correction for imbalances in age, sex, smoking and alcohol consumption (odds ratio = 0.2, 95% CI 0.1-0.5). Of the putatively risk genotypes, GSTM3 AA, previously associated with susceptibility to skin cancer, was higher in the cases (odds ratio = 1.6, 95% CI 1.1-2.4). Dividing cases into oral/pharyngeal and laryngeal squamous cell carcinoma showed the GSTM3 AA frequency was higher in laryngeal squamous cell carcinoma than control individuals (odds ratio = 1.6, 95% CI 1.1-2.5) and the difference between control individuals and oral/pharyngeal squamous cell carcinoma approached significance (odds ratio = 1.7, 95% CI 1.0-2.8). The putatively protective GSTM3 BB genotype was lower in patients with glottic (1.0%) than supraglottic (3.0%) squamous cell carcinoma. We identified no differences between patients and control individuals in the frequencies of presumed risk genotypes (e.g. CYP2D6 EM, CYP1A1 m1/m1, CYP1A1 Ile/Ile, CYP2E1 DD, CYP2E1 c1c1, GSTT1 null) or, interactions between genotypes and smoking or alcohol consumption. We conclude, first, that mu class glutathione S-transferase influence risk of upper aerodigestive tract cancers thereby complementing studies in skin cancer patients showing GSTM1 A/B is protective, while GSTM3 AA moderately increases risk. The influence of GSTM1 A/B, but not GSTM1 A or GSTM1 B (mostly heterozygotes with GSTM1*0) suggests that two expressed alleles may attenuate risk. While we found immunohistochemical evidence of GSTM3 expression in the cilia lining the larynx, the biochemical consequences of the polymorphism are unclear. Indeed, the influence of the gene may reflect linkage disequilibrium with another gene. However, we did not find an association with GSTM1 genotypes. Second, we conclude that the CYP2D6, CYP2E1, CYP1A1 and GSTT1 alleles studied, although putatively good candidates, either do not determine the effectiveness of detoxification of tobacco-derived carcinogens in the upper aerodigestive tract or, that chronic consumption of tobacco and alcohol overwhelms enzyme defences, irrespective of genotype.

Aged↗
PubMed1998

[Ameloblastoma of the maxillary sinus: an electron microscopy study].

BACKGROUND: The morphological demonstration and classification of rare tumor types occurring in the region of the head and neck may involve a number of problems. PATIENT AND METHODS: In the following the exceptional case of a plexiform ameloblastoma located in the main nasal cavity is presented. The morphological peculiarities of this locally destructive tumor are revealed by light and electron microscopy. RESULTS: The light microscopic investigations show one-layered epithelial units which are interlinked in a plexiform manner and extend as far as up to the surface epithelium. The electron microscopic investigations show solid and loosened areas. The organelles are well developed, their number varied; rough endoplasmic reticulum is scarce. Glycogen incorporations occur regularly. The tumor cells are connected with a number of desmosomes. The cell surface is characterized by microvilli. CONCLUSIONS: The combination of different methods of investigation is sometimes justified for diagnostic purposes. Especially electron microscopic studies may serve to demonstrate decisive structural peculiarities to classify a certain tumor type. Complete surgical removal is recommended. Postoperative radiation is generally advisable.

Aged↗
PubMed1998

Polymorphism within the cyclin D1 gene is associated with prognosis in patients with squamous cell carcinoma of the head and neck.

We have examined the correlation of a frequent A/G polymorphism within exon 4 of the cyclin D1 gene (CCND1) with genetic susceptibility and clinical outcome in 384 patients with squamous cell carcinoma (SCC) of the head and neck. CCND1 genotype frequencies were similar in the cases and 191 controls. Furthermore, the CCND1 genotype was not associated with susceptibility to SCC of the larynx, pharynx, or oral cavity. The influence of the CCND1 genotype on clinical outcome was also assessed. We found no correlation between genotype and tumor size (T1-T4), the involvement of nodes at presentation, or patient age and gender. However, the distribution of CCND1 genotypes in cases with poorly differentiated tumors was significantly different to that in patients with well-/moderately differentiated tumors (P = 0.016; chi2(2) = 8.71). Homozygosity for CCND1*G (GG genotype) was associated with poorly differentiated tumors (G3). We used Cox's proportional hazards model to investigate the influence of the CCND1 genotype on disease-free interval. CCND1 GG was associated with reduced disease-free interval [P = 0.001; hazard ratio (HR) = 2.95; 95% confidence interval (CI) = 1.54-5.63]. This remained significant after correction for tumor differentiation (P = 0.013; HR = 2.34; 95% CI = 1.2-4.6) and tumor stage (P = 0.005; HR = 2.64; 95% CI = 1.34-5.19). Analysis of the data from patients with tumors at different sites showed that the CCND1 GG genotype was associated with reduced disease-free interval in laryngeal (P = 0.004; HR = 3.63; 95% CI = 1.44-8.83) and pharyngeal (P = 0.006; HR = 3.48; 95% CI = 1.43-8.46) tumors. This is the first report of an association between CCND1 polymorphism and prognosis in SCC of the head and neck. These data show that the CCND1 GG genotype is an independent prognostic indicator of disease-free interval and supports initial observations in non-small cell lung cancer, that polymorphism within CCND1 influences tumor behavior.

Adult↗
PubMed1997

Patterns of chromosomal alterations in metastasizing and nonmetastasizing primary head and neck carcinomas.

In an attempt to define chromosomal alterations that are associated with the metastatic phenotype, we investigated a total of 29 metastasizing (pN+) and 19 non-metastasizing (pN0) head and neck squamous cell carcinomas by comparative genomic hybridization (CGH). The analysis indicated that the pN0 tumors carried preferentially overrepresentations of chromosomes 5p, 6p, and 7p and that the pN+ tumors were frequently characterized by deletions on chromosomes 7q, 10q, 11p, 11q, 15q, and 20p and overrepresentations of the chromosomes 19q and 20q. In particular, the use of difference histograms and statistical analysis indicated that the deletions on chromosomes 10q25-q26 and 11p13-p14 were highly significant for metastasizing carcinomas. The findings on chromosome 10q were supported by loss of heterozygosity analysis in the primary tumors and eight synchronous lymph node metastases using four microsatellite polymorphisms. The data suggest that distinct patterns of genetic lesions are responsible for the metastatic phenotype of head and neck squamous cell carcinomas.

Carcinoma, Squamous Cell↗
PubMed1997

Glutathione S-transferase and cytochrome P450 genotypes as risk factors for laryngeal carcinoma.

While cigarette smoking and alcohol consumption have been linked to laryngeal squamous cell carcinoma (SCC), the role of genetic factors in determining individual susceptibility is unknown. We describe the role of allelism at the glutathione S-transferase GSTM1, GSTM3, GSTT1 and cytochrome P450 CYP1A1, CYP2E1, CYP2D6 loci in determining individual susceptibility to laryngeal SCC. Enzyme genotypes were determined using polymerase chain reaction and restriction enzyme digestion of leukocyte DNA collected from 269 patients with T1-T4 laryngeal carcinomas and 216 controls. While the frequencies of the heterozygote GSTM1 A/B genotype and the homozygote GSTM3 B/B genotype were statistically significantly lower in the patients with tumors than in controls, the frequency of the GSTT1 null genotype was higher in the patients than in controls. The data suggest that allelism at GST loci mediates susceptibility to SCC of the larynx. GSTM1 A/B and GSTM3 B/B appear to be associated with reduced risk, while GSTT1 null may confer increased risk. These findings are compatible with the view that genetic predisposition is important in determining risk for this cancer.

Alcohol Drinking↗
PubMed1997

[A phase-I/II study on the local hyperthermia of cervical N2/N3 lymph node metastases].

BACKGROUND: Patients with advanced lymph node metastases from head and neck tumors at stage N2/N3 (i.e. UICC IV) present a difficult therapeutic problem. Despite combined radio-chemotherapy and hyperfractionated and/or accelerated fractionation regimens, local control of these tumors remains unsatisfactory. For this reason, the value of local radio wave/microwave hyperthermia was examined for this patient group in a phase I/II study.

Adult↗
PubMed1996

Local hyperthermia of N2/N3 cervical lymph node metastases: correlationof technical/thermal parameters and response.

PURPOSE: Patients with advanced head and neck carcinomas, primarily nonresectable as well as recurrent cases, were treated in multimodality regimens with radiotherapy, chemotherapy, and local hyperthermia. Commercially available microwave and radiowave applicators were used in 50 patients with N2/N3 cervical lymph node metastases during more than 250 heat treatments. To assess technical suitability, the achieved power densities and thermal parameters were tested for correlation with anatomical and geometrical factors. To assess effectiveness, the response was compared with derived parameters of the achieved temperature distributions. METHODS AND MATERIALS: The temperature measurement points (in thermometry catheters) documented by computerized tomography are labeled according to tissue depth, shielding by osseous structures, and location in relation to the external applicators. Relative and absolute specific absorption rates (SAR) and cooling coefficients are extracted from the temperature-time curves. Time-averaged temperature-position curves are evaluated to obtain index temperatures (T90, T50, T20), minimum/maximum tumor temperatures, cumulative minutes T90 > or = 43 degrees C, and 43 degrees C-equivalent min T90. Radiation dose, treatment time, and chemotherapy regiment are also considered. A response parameter is defined using the pre- and posttherapeutic tumor volumes. A multivariate variance analysis is performed for the dependent variables power density, thermal parameters, and response. RESULTS: A significant correlation exists between power density and absorption, presence of a fat layer, and applicator illumination. The maximum depth is 5 cm, where SAR of >= 10 mW/g are registered. Achieved temperatures at individual measurement points are dependent on the SAR, and to a lesser extent, the perfusion-dependent cooling coefficients, but the index temperature T90 is only significantly related to intratumorally achieved SAR. The thermal gradient (T20-T50) and temperature peak (T20) are significantly influenced by the tumor volume. The response is directly related to the index temperature T90, equivalent minute T90 43 degrees C, and cumulative minutes T90 > or = 40.5 degrees C, and inversely related to the tumor volume. CONCLUSIONS: Local hyperthermia using microwave and radiowave applicators in the head and neck region is a tolerable and clinically practical supplementary therapy used as part of multimodal regimens, and has already been proven to be effective. However, the analyses also demonstrated the limits of currently available technology, and confirm the need for continued methodical research.

Adult↗
PubMed1996

[Tissue engineering of human cartilage tissue for reconstructive surgery using biocompatible resorbable fibrin gel and polymer carriers].

Current practical approaches in cartilage engineering still face problems with three dimensional cell distribution or require components for cell immobilization, raising biocompatibility problems. In this study, we present a new model using cells cross-linked by fibrin within biocompatible resorbable polymers. Both components have been in clinical use for a long time. Immunohistochemical procedures showed that this model provides optimal requirements for in vitro cartilage production. Immunochemically, cartilage-specific extracellular components such as proteoglycan, chondroitin sulfate and collagen II were characterized. Histomorphological methods showed a mechanically stable tissue compound that lasted for at least 5 weeks. This model may be the first to provide all biocompatible requirements for in vitro production of autologous cartilage transplants for reconstructive surgery.

Biocompatible Materials↗
PubMed1996

Glutathione S-transferase and cytochrome-P-450 polymorphism as risk factors for squamous cell carcinoma of the larynx.

PURPOSE: While cigarette smoking and alcohol consumption are recognized covariates for laryngeal carcinoma, the role of genetic factors in determining individual susceptibility is unknown. We describe the influence of polymorphism in carcinogen-metabolizing enzymes on susceptibility to squamous cell carcinoma of the larynx. MATERIAL AND METHODS: We investigated 269 patients with T1-T4 laryngeal carcinoma and 216 controls. Enzyme genotypes at the glutathione-S-transferase GSTM1 (A, B, A/B, null), GSTM3 (A, B), GSTT1 (null and expressors), and cytochrome P-450, CYP2D6 (intron 3/exon 4 boundary mutation and exon 5 deletion), CYP1A1 (3'-mutation and exon 7 mutation), and CYP2E1 (mutation at the 5' flanking region) loci were determined using polymerase chain reaction and restriction-based approaches. RESULTS: While the frequencies of the heterozygote GSTM1 A/B and homocygote GSTM3 B/ B were statistically significantly lower in cases than controls, the frequency of the GSTT1 null genotype was higher in the cases than controls. Genotype frequencies of 123 patients suffering squamous cell carcinomas located at different sites within the upper aerodigestive tract showed no differences between cases and controls. CONCLUSIONS: The data provide evidence that susceptibility to laryngeal carcinoma, but not pharyngeal carcinoma, is mediated by allelism at a number of loci encoding enzymes involved in the detoxification of electrophils derived from environmental pollution including cigarette smoke.

Carcinoma, Squamous Cell↗
PubMed1995

[MR-guided laser-induced thermotherapy in tumors of the head and neck region: initial clinical results].

PURPOSE: To analyse the value of MR-guided laser-induced thermotherapy (LITT) for palliative treatment of recurrent tumours of the head and neck region. MATERIAL AND METHODS: 8 patients with recurrent tumours of the head and neck region (squamous cell carcinomas n = 6, pleomorphic adenomas n = 2) underwent MR-controlled LITT. A 7 French laser applicator was inserted under local anaesthesia into the centre of the recurrent tumour. A Nd:YAG laser with a wavelength of 1064 nm was used. Therapy was monitored on-line using special MR thermosequences. RESULTS: Preinterventional contrast-enhanced MRI revealed a recurrent tumour of the head and neck region for all eight patients. All patients tolerated the procedures well under local anaesthesia, with no clinically relevant side effects. The MR thermosequences depicted up to 15 mm diameter areas of less signal near the laser tip. Postinterventional contrast-enhanced MRI revealed hypovascularized areas due to the resulting coagulative necrosis. Coagulative necrosis of 4 cc to 28 cc occurred in all patients, and a reduction of clinical symptoms was achieved in five. CONCLUSION: The results obtained indicate that minimal invasive LITT can be a therapeutic alternative for palliative treatment of head and neck tumours.

Adenoma, Pleomorphic↗
PubMed1995

[Initial results of glutathione-S-transferase GSTM1 and GSTT1 genotypes and genetic predisposition for laryngeal carcinoma].

BACKGROUND: While cigarette smoking and alcohol consumption have been linked to laryngeal carcinoma, the role of genetic factors in determining individual susceptibility is unknown. We describe the role of allelism at glutathione-S-transferase GSTM1, GSTT1, and cytochrome P 450 CYP2D6 loci in determining individual susceptibility to laryngeal squamous cell carcinoma. METHODS: Enzyme genotypes were determined using the polymerase chain reaction in 169 patients suffering T1-T4 laryngeal carcinoma and in 145 controls. RESULTS: While the frequency of the heterozygote GSTM1 A/B genotype was statistically significantly lower in the cases than controls, the frequency of the GSTT1 null genotype was higher in cases than controls. CONCLUSION: These initial data suggest that allelism at GST loci mediates susceptibility to squamous cell carcinoma of the larynx. Thus, GSTM1 A/B appears to be associated with a reduced risk while GSTT1 null confers increased risk. The findings are compatible with the view that genetic predisposition is important in determining risk of this cancer.

Adult↗
PubMed1995

[Polysomnographic results before and after uvulopalatopharyngoplasty (UPPP)].

Uvulo-palato-pharyngo-plastic is one possibility for treatment of obstructive sleep-apnea. We examined in a prospective study design 36 patients, suffering from polysomnographically ensured obstructive sleep-apnea-syndrome, who were undergone uvulo-palato-pharyngo-plastic. We analysed pre- und postoperative polysomnographic data. Most of patients demonstrated a decrease of amount of apneas, duration of apneas and an increase of minimal oxygen-desaturation. Patients who had high amounts of apneas (AI > 40/h) or who had a Broca-index > 140 p.c. gained not as much from surgical treatment as other patients did.

Adult↗
PubMed1994

[Non-squamous epithelial malignancies of the larynx with special reference to MRT diagnosis].

Non-squamous malignancies of the larynx are extremely rare, usually subsurface in origin and mostly diagnosed only in an advanced stage. Two cases representative of this group are described, namely, an adenoid cystic carcinoma and a pleomorphic rhabdomyosarcoma. The clinicopathological data of these unusual tumours are presented and the current therapeutic modalities discussed. The diagnostic value of MRI with contrast medium is emphasised by demonstrating an otherwise not recognised far advanced tumour stage. The pleomorphic rhabdomyosarcoma was also examined via electron microscopy.

Carcinoma, Adenoid Cystic↗
PubMed1993

[Intraepithelial mast cells in the vocal cords and nasal mucosa].

Leukocytes and mast cells have been described in the human nasal mucosa and epithelium of the lower airways (Bonneville 1988, Goodman and Lefrancois 1989, Guy-Grand 1991, Denburg 1992). In mast cells, heterogeneity of mucosal and connective tissue mast cells has been observed. In the present electron microscopic study, the epithelium of the upper airways (larynx and nose) of patients, suffering from chronic laryngitis, was examined with special regard to intraepithelial mast cells. Numerous mast cells were found in the stratum spinosum of the true vocal cords showing extensive elongated surface folds that had little contact to epithelial cells. Desmosomes were absent. Mucosal mast cells are characterised by four types of membrane-bounded granules, whereas serosal mast cells only showed two different types of granules and resembled blood basophiles. Migration of connective tissue mast cells into the epithelium could not be observed. According to our findings, mucosal and serosal mast cells belong to different cell lines.

Adult↗