Inhibition of the bacterial lectins of Pseudomonas aeruginosa with monosaccharides and peptides.

Pseudomonas aeruginosa (PA) can cause infections in compromised hosts by interacting with the glycocalyx of host epithelial cells. It binds to glycostructures on mucosal surfaces via two lectins, which are carbohydrate-binding proteins, named PA-IL and PA-IIL, and blocking this interaction is, thus, an attractive anti-adhesive strategy. The aim of this study was to determine by ciliary beat frequency (CBF) analysis whether monosaccharides or peptides mimicking glycostructures represent blockers of PA lectin binding to human airway cilia. The treatment with monosaccharides and peptides alone did not change the CBF compared to controls and the tested compounds did not influence the cell morphology or survival, with the exception of peptide pOM3. PA-IL caused a decrease of the CBF within 24 h. D-galactose as well as the peptides mimicking HNK-1, polysialic acid and fucose compensated the CBF-modulating effect of PA-IL with different affinities. PA-IIL also bound to the human airway cilia in cell culture and resulted in a decrease of the CBF within 24 h. L(-)-fucose and pHNK-1 blocked the CBF-decreasing effect of PA-IIL. The HNK-1-specific glycomimetic peptide had a high affinity for binding to both PA-IL and PA-IIL, and inhibited the ciliotoxic effect of both lectins, thus, making it a strong candidate for a therapeutic anti-adhesive drug.

Monitoring of gustatory stimulation of salivary glands by diffusion-weighted MR imaging: comparison of 1.5T and 3T.

BACKGROUND AND PURPOSE: Our aim was to compare different field strengths monitoring physiologic changes due to oral stimulation of parotid glands by using diffusion-weighted (DW) echo-planar imaging (EPI). MATERIALS AND METHODS: Twenty-seven healthy volunteers were examined with a DW-EPI sequence at 1.5T and 3T before and after oral stimulation with commercially available lemon juice. The b factors used were 0, 500, and 1000 s/mm(2). Apparent diffusion coefficient (ADC) maps were evaluated with a manually placed region of interest including the entire parotid gland. For comparison of results, a Student t test was used on the basis of the mean of the volunteer median values. To compare both field strengths, we calculated the Pearson correlation coefficient (r). RESULTS: DW-EPI MR imaging visualized the parotid glands of all volunteers. With 1.5T, the mean ADC before stimulation was 1.12 x 10(-3) mm(2)/s +/- 0.08 x 10(-3) mm(2)/s. After stimulation with lemon juice, the ADC increased to 1.18 x 10(-3) mm(2)/s +/- 0.09 x 10(-3) mm(2)/s. For 3T, the ADC before stimulation was 1.14 x 10(-3) mm(2)/s +/- 0.04 x 10(-3) mm(2)/s, with an increase to 1.17 x 10(-3) mm(2)/s +/- 0.05 x 10(-3) mm(2)/s after stimulation. For both field strengths, the increase in ADC after stimulation was significant (P < .001). High correlations between both field strengths were found pre- and poststimulation (r = 0.955, and 0.936, respectively). CONCLUSION: DW-EPI MR imaging allows monitoring of physiologic changes due to oral stimulation of parotid glands by using DW imaging with high correlation between 1.5T and 3T.

[MR sialography: evaluation of an ultra-fast sequence in consideration of a parallel acquisition technique and different functional conditions in patients with salivary gland diseases]. / MR-Sialographie: Prospektive Evaluation ultraschneller Sequenzen mit paralleler Bildgebung und oraler Stimulation bei Patienten.

PURPOSE: To evaluate an ultra-fast sequence for MR sialography requiring no post-processing and to compare the acquisition technique regarding the effect of oral stimulation with a parallel acquisition technique in patients with salivary gland diseases. MATERIALS AND METHODS: 128 patients with salivary gland disease were prospectively examined using a 1.5-T superconducting system with a 30 mT/m maximum gradient capability and a maximum slew rate of 125 mT/m/sec. A single-shot turbo-spin-echo sequence (ss-TSE) with an acquisition time of 2.8 sec was used in transverse and oblique sagittal orientation. All images were obtained with and without a parallel imaging technique. The evaluation of the ductal system of the parotid and submandibular gland was performed using a visual scale of 1-5 for each side. The images were assessed by two independent experienced radiologists. An ANOVA with post-hoc comparisons and an overall two tailed significance level of p = 0.05 was used for the statistical evaluation. An intraclass correlation was computed to evaluate interobserver variability and a correlation of > 0.8 was determined, thereby indicating a high correlation. RESULTS: Depending on the diagnosed diseases and the absence of abruption of the ducts, all parts of excretory ducts were able to be visualized in all patients using the developed technique with an overall rating for all ducts of 2.70 (SD +/- 0.89). A high correlation was achieved between the two observers with an intraclass correlation of 0.73. Oral application of a sialogogum improved the visibility of excretory ducts significantly (p < 0.001). In contrast, the use of a parallel imaging technique led to a significant decrease in image quality (p = 0,011). CONCLUSION: The applied ss-TSE for MR sialography allows fast and sufficient visualization of the excretory ducts of the main salivary glands in patients, and no elaborate post-processing is required. Use of an oral sialogogum is suggested to improve the results of MR sialography.

[Functional imaging of submandibular glands: diffusion-weighted echo-planar MRI before and after stimulation]. / Diffusionsgewichtete MRT zur Funktionsdiagnostik der Glandula submandibularis.

PURPOSE: To investigate the feasibility of diffusion-weighted (DWI) echo-planar imaging (EPI) to depict the submandibular glands and to measure different functional conditions. MATERIALS AND METHODS: Twenty-seven healthy volunteers were examined. Diffusion weighted sequence was performed prior to stimulation. Exactly 30 seconds after a commercially available lemon juice was given orally, the diffusion weighted sequence was repeated. All examinations were performed by using a 1.5-T superconducting system with a 30 mT/m maximum gradient capability and maximum slew rate of 125 mT/m/sec (Magnetom Symphony, Siemens, Erlangen, Germany). The lower part of the circularly polarized (CP) head coil and a standard two-element CP neck array coil were used. The flexibility of the neck array coil allowed positioning the N1 element (upper part of the coil) right next to the submandibular gland. The axial diffusion-weighted EPI (echo planar imaging) sequence was performed using a matrix of 119 x 128, a field of view of 250 x 250 mm (pixel size 2.1 x 1.95 mm), a section thickness of 5 mm with an interslice gap of 1 mm. The b factors used were 0 sec/mm(2), 500 sec/ mm(2) and 1000 sec/mm(2). Apparent diffusion coefficiant (ADC) maps were digitally transferred to MRIcro (Chris Rorden, Universitiy of Nottingham, Great Britain). After detecting the submandibular glands a region of interest (ROI) was placed manually exactly within the boarder of both submandibular glands, excluding the external carotid artery on ADC maps. These procedures were performed on all ADC slices the submandibular glands could be differentiated in before and after oral stimulation. For statistical comparison of results, a student's t-test was performed with an overall two-tailed significance level of p = 0.05. RESULTS: The visualization of the submandibular glands using the diffusion-weighted EPI sequence was possible in all of the 27 volunteers. Prior to oral stimulation an ADC of 1.31 x 10(-3) mm(2)/sec (95 % CI, 1.39 x 10(-3) mm(2)/sec, 1.44 x 10(-3) mm(2)/sec) was calculated which increased to 1.41 x 10(-3) mm(2)/sec (95 % KI, 1.39 x 10(- 3) mm(2)/sec, 1.44 x 10(-3) mm(2)/sec) 30 seconds after stimulation. This increase proved to be significant (p < 0.001). CONCLUSION: Diffusion-weighted echo-planar MR imaging allows non-invasive quantification of functional changes in the submandibular gland.

Diffusion-weighted echo-planar MRI: a valuable tool for differentiating primary parotid gland tumors?

PURPOSE: To investigate the feasibility of using diffusion-weighted (DW) echo-planar imaging (EPI) for differentiating primary parotid gland tumors. MATERIAL AND METHODS: Fifty consecutive patients with a suspected primary tumor of the parotid gland were examined with a DW EPI sequence (TR 1,500 msec, TE 77 msec, field of view 250 x 250 mm, pixel size 2.10 x 1.95 mm, section thickness 5 mm). The b factors used were 0, 500, and 1,000 sec/mm (2). Apparent diffusion coefficient (ADC) maps were digitally transferred to MRIcro (Chris Rorden, University of Nottingham, Great Britain) and evaluated with a manually placed irregular region of interest (ROI) containing the entire tumor. Additionally, the contralateral, non affected parotid gland was measured and a circular ROI containing 100 - 200 pixels was placed in the cerebrospinal fluid (CSF) next to the spinal cord in every patient. For comparison of the results, the two-tailed Student's t test was used, based on the median ADC values for each patient, and a p-value <.05 was determined to indicate statistical significance. RESULTS: In 45 patients, a primary neoplasm of the parotid gland could be histologically verified. For the non-affected parotid glands of all 45 evaluated patients, the mean ADC value was 1.14 x 10 ( - 3) mm (2)/sec +/- 0.12 x 10 ( - 3) mm (2)/sec (mean +/- standard deviation). Seven different entities of parotid gland tumors were histologically discriminated. Pleomorphic adenomas (2.14 x 10 ( - 3) mm (2)/sec +/- 0.11 x 10 ( - 3) mm (2)/sec), Warthin tumors (0.85 x 10 ( - 3) mm (2)/sec +/- 0.1 x 10 ( - 3) mm (2)/sec), and mucoepidermoid carcinomas (1.04 x 10 ( - 3) mm (2)/sec +/- 0.3 x 10 ( - 3) mm (2)/sec) showed statistically significant different ADC values in comparison to all other evaluated tumors (p .001), and also among each other (p <.001). Additionally, ADC values presented by lipomas were statistically significant compared to all other entities (p <.001 to .015). Among all other [corrected] primary malignant parotid gland tumors, no statistically significant ADC values could be observed (p .18 to 1). CONCLUSION: Diffusion-weighted echo-planar MRI seems to be a valuable tool for differentiating benign from malignant primary parotid gland tumors.

[MR-sialography: optimisation and evaluation of an ultra-fast sequence in parallel acquisition technique and different functional conditions of salivary glands]. / MR-Sialographie: Optimierung und Bewertung ultraschneller Sequenzen mit paralleler Bildgebung und oraler Stimulation.

PURPOSE: To optimise a fast sequence for MR-sialography and to compare a parallel and non-parallel acquisition technique. Additionally, the effect of oral stimulation regarding the image quality was evaluated. MATERIAL AND METHODS: All examinations were performed by using a 1.5-T superconducting system. After developing a sufficient sequence for MR-sialography, a single-shot turbo-spin-echo sequence (ss-TSE) with an acquisition time of 2.8 sec was used in transverse and oblique sagittal orientation in 27 healthy volunteers. All images were performed with and without parallel imaging technique. The assessment of the ductal system of the submandibular and parotid gland was performed using a 1 to 5 visual scale for each side separately. Images were evaluated by four independent experienced radiologists. For statistical evaluation, an ANOVA with post-hoc comparisons was used with an overall two-tailed significance level of P =.05. For evaluation of interobserver variability, an intraclass correlation was computed and correlation >.08 was determined to indicate a high correlation. RESULTS: All parts of salivary excretal ducts could be visualised in all volunteers, with an overall rating for all ducts of 2.26 (SD +/- 1.09). Between the four observers a high correlation could be obtained with an intraclass correlation of 0.9475. A significant influence regarding the slice angulations could not be obtained (p = 0.74). In all healthy volunteers the visibility of excretory ducts improved significantly after oral application of a Sialogogum (p < 0.001; eta (2) = 0.049). The use of a parallel imaging technique did not lead to an improvement of visualisation, showing a significant loss of image quality compared to an acquisition technique without parallel imaging (p < 0.001; eta (2) = 0.013). CONCLUSION: The optimised ss-TSE MR-sialography seems to be a fast and sufficient technique for visualisation of excretory ducts of the main salivary glands, with no elaborate post-processing needed. To improve results of MR-sialography, it is reasonable to use an oral Sialogogum.

Functional imaging of parotid glands: diffusion-weighted echo-planar MRI before and after stimulation.

PURPOSE: To investigate the feasibility of diffusion-weighted (DW) echo-planar imaging (EPI) for measuring different functional conditions of the parotid gland and to compare different measurement approaches. MATERIALS AND METHODS: Parotid glands of 27 healthy volunteers were examined with a DW EPI sequence (TR 1,500 msec, TE 77 msec, field-of-view 250 x 250 mm, pixel size 2.10 x 1.95 mm, section thickness 5 mm) before and after oral stimulation with commercially available lemon juice. The b factors used were 0, 500, and 1,000 sec/mm (2). Apparent diffusion coefficient (ADC) maps were digitally transferred to MRIcro (Chris Rorden, University of Nottingham, Great Britain) and evaluated with a manually placed circular region of interest (ROI) containing 100 - 200 pixel. Additional ROIs including the entire parotid gland were placed on either side. The results of both measurements were compared, using the Student's t test based on the median ADC values for each person. A two-tailed p-value of less than.05 was determined to indicate statistical significance. To compare both measurement approaches, the Pearson's correlation coefficient (r) was calculated. RESULTS: Diffusion-weighted echo-planar MR imaging successfully visualized the parotid glands of all volunteers. In a first step, the median ADC value per person was computed. Using ROIs of 100 - 200 pixels, the mean was calculated to be 1.08 x 10 (- 3) mm (2)/sec +/- 0.12 x 10 (- 3) mm (2)/sec for both parotid glands prior to stimulation. After stimulation, the mean ADC was measured at 1.15 x 10 (- 3) mm (2)/sec +/- 0.11 x 10 (- 3) mm (2)/sec for both parotid glands. Evaluating the entire parotid gland, the ADC was 1.12 x 10 (- 3) mm (2)/sec +/- 0.08 x 10 (- 3) mm (2)/sec prior to stimulation, whereas the ADC increased to 1.18 x 10 (- 3) mm (2)/sec +/- 0.09 x 10 (- 3) mm (2)/sec after stimulation with lemon juice. For both types of measurements, the increase in ADC after stimulation proved to be significant (p < 0.001). High correlations between both measurement types were found (r >.83). CONCLUSION: Diffusion-weighted echo-planar MR imaging allows non-invasive quantification of functional changes in the parotid glands.

The clinical presentation of non-hodgkin lymphomas of the major salivary glands.

The aim of this study was to examine the clinical presentation of patients with malignant lymphoma of the major salivary glands. In a retrospective study, 26 patients with a non-Hodgkin lymphoma (NHL) of the major salivary glands were examined. The results showed a distinct preference for the female gender. Two groups with clinical differences were observed depending on lymphoma manifestation as either extranodal-parenchymal (extranodal) or with intra- or periglandular (nodal) lymph node disease. Differences between these two groups existed with regard to the length of clinical history, recurrent vs continuously progressing symptoms and presentation on ultrasound examination (multiple masses compared to solitary masses). Patients with an extranodal lymphoma always showed disease limited to the affected gland, whereas those patients with a nodal lymphoma presented with stage II or higher (Ann Arbor Classification). In these patients, local recurrence was also five times higher (5/13; 38.4%) than in patients with an extranodal lymphoma (1/13; 7.7%). In 1 patient (7.7%) with extranodal lymphoma, dissemination was observed, compared to 6/13 patients (46.2%) in the group with nodal disease. Seven out of 13 patients (53.8%) with nodal disease died due to lymphoma spread and 1/13 (7.7%) of the patients with extranodal disease. There seem to be distinct clinical differences in the course of patients with NHL of the major salivary glands, depending on extranodal or nodal disease presentation. The histopathological diagnosis, with special recognition of the particular lymphoma pathogenesis, constitutes an important prognostic factor in these patients.

Benign and malignant salivary gland diseases in children A retrospective study of 549 cases from the Salivary Gland Registry, Hamburg.

OBJECTIVE: Tumors of salivary glands in children are rare. Basically all types of salivary gland diseases during the period of childhood are described. The incidences of salivary gland tumors in children (0-14 years) differ completely from those in adults. Especially the malignant neoplasms are very rarely described in literature. Only some collective reviews and case reports try to summarize frequency, distribution concerning sex and age, morphology and localization. METHODS: In our study we were able to draw data from the Hamburg Salivary Gland Registry, concerning the last 25 years regarding histopathological diagnosis, age, gender and localisation of the pathologies. Findings were compared to other studies. Most of the specimens were presented by the Clinic for Otorhinolaryngology and Head and Neck Surgery, University Hamburg, Eppendorf. As a reference centre for salivary gland diseases some material was sent by other institutions. RESULTS: This study will give a detailed survey of salivary gland diseases and tumors in children up to the age of 14 which have undergone surgical therapy/biopsy. We present the general distribution of the different tumors/diseases, the distribution in certain age groups and the various locations. 549 cases could be examined. Comparing the distribution of malignant tumors with other studies, the epithelial-myoepithelial carcinomas followed by salivary duct carcinomas represent the largest group in childhood. CONCLUSIONS: The study shows that comparing to adulthood different tumors play an important role in adolescence. The distribution of tumors in childhood may help in diagnostic. Further many salivary gland diseases in childhood underwent surgery/biopsy although this is not supposed to be the proper treatment. The study shows that the right diagnosis most often can only be reached by surgery and histology.

Diffusion-weighted echo-planar MR imaging of primary parotid gland tumors: is a prediction of different histologic subtypes possible?

BACKGROUND AND PURPOSE: Our aim was to determine the value of echo-planar diffusion-weighted MR imaging (epiDWI) in differentiating various types of primary parotid gland tumors. MATERIALS AND METHODS: One hundred forty-nine consecutive patients with suspected tumors of the parotid gland were examined with an epiDWI sequence by using a 1.5T unit. Image analysis was performed by 2 radiologists independently, and the intraclass correlation coefficient was computed. Histologic diagnosis was obtained in every patient. For comparison of apparent diffusion coefficients (ADCs), a paired 2-tailed Student t test with a Bonferroni correction was used. RESULTS: In 136 patients, a primary parotid gland tumor was confirmed by histology. Among the observers, a high correlation was calculated (0.98). ADC values of pleomorphic adenomas were significantly higher than those of all other entities, except for myoepithelial adenomas (P = .054). ADC values of Warthin tumors were different from those of myoepithelial adenomas, lipomas, and salivary duct carcinomas (P < .001, 0.013, and .037, respectively). Mucoepidermoid carcinomas, acinic cell carcinomas, and basal cell adenocarcinomas were not differentiable from Warthin tumors (P = .094, .396, and .604, respectively). CONCLUSION: epiDWI has the potential to differentiate pleomorphic adenoma and myoepithelial adenomas from all other examined entities. Due to an overlap not only within the group of benign and malignant lesions but also between groups, diagnoses should not be addressed on the basis of ADC values solely. Therefore, further studies combining DWI, morphologic criteria, and probably other MR imaging techniques seem warranted.

Sjögren's syndrome of the parotid gland: value of diffusion-weighted echo-planar MRI for diagnosis at an early stage based on MR sialography grading in comparison with healthy volunteers.

PURPOSE: To investigate the value of diffusion-weighted echo-planar imaging (DW-EPI) for quantifying functional changes of the parotid gland in Sjögren's disease and to evaluate whether ADC mapping allows for early diagnosis based on MR sialography grading. MATERIALS AND METHODS: Using a DW-EPI sequence at 1.5 T (b-factors: 0, 500 and 1000 sec/mm (2)), the parotid glands of 52 healthy volunteers and 13 patients with histologically verified affection of Sjögren's disease were examined. All scans were performed prior to and following gustatory stimulation with 5 ml of lemon juice. ADC maps were evaluated by placing an inordinate region-of-interest (ROI) enclosing the entire parotid gland. Sjögren's disease was graded based on MR sialography findings using a 4-point grading-scale. Statistics included student t-test and kappa-analysis. RESULTS: In healthy volunteers mean ADCs of 1.14 x 10 (-3 )mm (2) /sec before and 1.2 x 10 (-3) mm (2) /sec after stimulation were observed. Higher ADCs were determined for early-stage Sjögren's disease, averaging 1.22 x 10 (-3) mm (2) /sec before and 1.29 x 10 (-3) mm (2) /sec after stimulation. Advanced disease revealed significantly lower ADCs (0.97 x 10 (-3) mm (2) /sec (p = 0.002) before and 1.01 x 10 (-3) mm (2) /sec (p < 0.001) after stimulation). CONCLUSION: DW-EPI seems to display functional changes of the parotid gland affected by Sjögren's disease. Combined with MR sialography, it might be a useful tool for discriminating healthy from affected glands and seems to allow differentiation between the early and advanced disease.

Value of apparent diffusion coefficient calculation before and after gustatory stimulation in the diagnosis of acute or chronic parotitis.

The purpose of the study was to investigate the value of diffusion-weighted (DW) echo-planar imaging (EPI) for quantifying physiological changes of the parotid gland before and after gustatory stimulation in patients suffering from acute or chronic recurrent inflammation in comparison with healthy volunteers. Using a DW-EPI sequence at 1.5 T, parotid glands of 19 consecutive patients with acute (n=14) and chronic (n=5) inflammation of parotid glands and 52 healthy volunteers were examined. Magnetic-resonance (MR) images were obtained before and after gustatory stimulation with 5 cc of lemon juice. In volunteers mean ADC values of 1.14 x 10(-3) mm(2)/s before and 1.2 x 10(-3) mm(2)/s after gustatory stimulation were observed. In acute inflammation ADC values were higher before [1.22 x 10(-3) mm(2)/s (p=0.006)] and after stimulation [1.32 x 10(-3) mm(2)/s (p<0.001)]. Before stimulation ADC differences between chronic inflammation (1.05 x 10(-3) mm(2)/s) and healthy volunteers (p=0.04) as well as between acute and chronic inflammation (p=0.005) were statistically significant. No differences were detected after stimulation between chronic inflammation (1.2 x 10(-3) mm(2)/s) and healthy volunteers (p=0.94) and between acute and chronic inflammation (p=0.15), respectively. DW-EPI seems to display the physiological changes of the parotid gland in patients suffering from acute or chronic inflammation and might be useful for discriminating healthy from affected glands.

[Ultrafast MR sialography: comparison of two coil systems including an alternative surface coil]. / Ultraschnelle MR-Sialografie: Intraindividueller Vergleich einer Oberflächenempfangs- mit einer konventionellen Kopf-Hals-Spule.

PURPOSE: To compare the visualization of salivary ducts by ultrafast magnetic resonance sialography (MR sialography) using an alternative surface coil and a conventional head-neck coil. MATERIALS AND METHODS: In 11 healthy volunteers, ultrafast MR sialography (single shot turbo spin echo; acquisition time, 2.8 s) was performed before and after oral application of a sialogogue. Each subject received examinations with both a bilateral surface coil (SC) and a conventional head-neck coil (HNC). The depiction of parotideal and submandibular duct systems was graded from 1 to 5 (5 = poor) by four independent radiologists. ANOVA served for statistical analysis of duct rankings, and interobserver variability was determined by Intraclass Correlation Coefficient (ICC). RESULTS: With an excellent ICC of 0.96, both coil systems offered symmetric visualization of salivary ducts, and the image quality increased after oral application of sialogogue (p < 0.001). In total, the overall rating was worse for SC than for HNC (2.13 +/- 1.24 vs. 1.45 +/- 0.65, p < 0.001). SC was especially inferior in depiction of submandibular and extraglandular duct components compared to HNC (p < 0.001). CONCLUSION: Most notably due to the reduced visualization of extraglandular and submandibular ducts, the specific surface coil used in this study was inferior in image quality and does not constitute a reasonable alternative to conventional coil systems.

[Ultrastructural analysis of secretion-transport through the parotid duct]. / Ultrastukturelle Analysen zum Sekrettransport im Ductus parotideus.

BACKGROUND: Mechanisms of secretion transport through the parotid duct (stenon's duct) and their influence on diseases of the parotid gland have not been investigated sufficiently until today. METHODS: According to this background we performed histologic and scanning electron microscopical investigations of 23 parotid ducts in order to investigate the arrangement of fibrillar structures of the duct as well as get deeper insights into the physiology of secretion transport mechanisms. RESULTS: The subepithelial soft tissue of the parotid duct could be divided into two layers. The inner layer measured about 100-200 microm and consisted of collagen and elastic fibres running in a spiral arrangement. The outer layer varied in its thickness and was composed of collageous fibres, which were mostly arranged longitudinally. CONCLUSIONS: The arrangement of collagen fibrils in the wall of the parotid duct seems to influence secretion transport. Due to the spiral organization of collagen fibrils, distension of the duct is likely to be associated with a "wring-out" mechanism leading to unidirectional transport of saliva into the oral cavity. A muscular sphincter at the outlet of the parotid duct did not exist. The duct pierced the buccinatory muscle. Here, it was surrounded by sceletal muscle fibres that lead to a functional closure during contraction. Our results indicate that an active transport of saliva through the parotid duct--as so far assumed--is unlikely.

Antimicrobial defence mechanisms of the human parotid duct.

The parotid duct transports saliva from the gland into the oral cavity. However, its immune response properties, along with the secretion and moistening principles of the duct, have not yet been fully investigated. These properties may play an important role in protecting the parotid gland from infection and also prevent development of sialodocholithiasis, as the parotid duct -- in contrast to the submandibular salivary duct -- is often free of duct concrements. Up to now, only the parotid gland has been investigated, without regard to its duct. The present study analyses the structures of the parotid duct in their relations to antimicrobial defence mechanisms and rheological properties. Investigations were performed on 23 parotid ducts using histological, histochemical and immunohistochemical methods. Epithelial and goblet cells of the parotid duct synthesize a complex mucous layer that covers the epithelium. The viscosity is influenced by secreted mucins and TFF peptides. This layer contains carbohydrates including N-acetyl-glucosamine, N-acetyl-galactosamine, galactose, mannose, fucose and sialic acids. The lamina propria contains granulocytes, T lymphocytes and macrophages. IgA, produced by plasma cells in the subepithelial layer, is frequently integrated in the secretory product. Synthesized mucins, TFF peptides, carbohydrates and immunoglobulins form a complex layer that can be expected to prohibit infection and enables salivary flow. Our study demonstrates that the steady secretion of the parotid gland, together with the ductal cellular and biochemical immune protection system, is likely to thwart ascending infections in the parotid duct and gland.

[Salivary duct carcinoma of the submandibular gland]. / Speichelgangkarzinome der Glandula submandibularis.

BACKGROUND: Salivary duct carcinoma (SDC) is a rare adenocarcinoma of the salivary glands which usually occurs in the parotid gland (approx. 80%), but is also found in the submandibular gland (approx. 12%) and the minor salivary glands. Due to the low incidence of this tumour-particularly in terms of involvement of the submandibular and minor salivary glands-only limited clinical data is available. PATIENTS/METHOD: In a retrospective investigation, follow-ups of six patients with a SDC of the submandibular gland were analysed and the surgical measures evaluated for their efficiency. RESULTS: At the time of diagnosis, varying tumor stages were present (2xT1, 3xT2, 1xT1). Initial lymph node metastasis was observed in four (66.6%) of the six patients. In all patients, the submandibular gland was resected and neck dissection performed, in two cases (33,3%) this was followed by radiotherapy. Four patients developed a life-threatening local recurrence. Only one patient developed distant metastasis. Two thirds of the patients died due to tumor-related disease after an average of 35.5 months. CONCLUSION: The clinical course of patients with SDC of the submandibular gland exhibits a high (66.6%) rate of local recurrence, crucial for the following clinical course. The treatment of these patients, therefore, must include radical tumor resection as well as tissue resection with a wide margin.

Sodium selenite is a potent radioprotector of the salivary glands of the rat: acute effects on the morphology and parenchymal function during fractioned irradiation.

In vitro studies show that sodium selenite is a potential radioprotector in normal cultural cells, but not in tumor cells. The aim of this study was to evaluate the cytoprotective potency of sodium selenite during a conventional fractioned irradiation of the salivary glands of rats. The head and neck area of male WAG/RijH rats was irradiated with (60)Co-gamma rays (60 Gy/30 fractions/6 weeks). Sodium selenite (15 microg/kg body weight) was applied through a venous port 30 min before irradiation. Rats of a control group were treated in the same manner with an equal volume of physiologic sodium chloride. In the course of treatment, the salivary glands were resected at different stages and examined histopathologically. The evaluation of gland function was performed prior to and after radiotherapy by sialoscintigraphy. The irradiation caused dose-dependent damage in the salivary glands. Intra- and intercellular edema (16 Gy), vacuolization (30 Gy), degranulation (46 Gy) and necrosis of the acinar cells (60 Gy) occurred. Sodium selenite delayed the development of the described damage; additionally, the number of necrotic acinar cells after the application of 60 Gy was reduced (control, 75% vs. sodium selenite, 30%). The sialoscintigaphical results confirmed these results: the loss in gland function in the control group was 74 vs. 44% (P < 0.05) in the sodium selenite group. Based on the morphological and sialoscintigraphical findings, a cytoprotective effect on the acute toxicity of the salivary glands of rats could be detected during irradiation with synchronous application of sodium selenite.

[Clinical aspects and therapy of extratemporal facial neurinoma]. / Zur Klinik und Therapie des extratemporalen Fazialisneurinoms.

BACKGROUND AND OBJECTIVE: Extratemporal facial nerve neurinomas are rare. In the present study, the epidemiology, clinical presentation and in particular surgical treatment of this entity was analysed under special focus on facial nerve preservation. PATIENTS/METHODS: 22 patients with an extratemporal facial nerve neurinoma of the parotid gland, treated at the University-ENT-Clinic Hamburg-Eppendorf during 1977-1997 were analysed retrospectively. RESULTS: All patients presented with a unilateral parotid mass, on ultrasound examination regularly an encapsulated intraparotideal tumor. 16 patients (72.7%) had regular facial nerve functioning. 6 patients (27.3%) with partial or complete peripheral facial nerve paralysis were treated with partial or radical parotidectomy because of malignancy possibility. In the group of patients with intact facial nerve, latero-facial (superficial) parotidectomy with segmental nerve resection was undertaken in 9 cases (56.3%) because nerve-continuity was not siezable within the tumor area. In 7 cases (43.7%), tumor-enucleation was feasable with complete nerve preservation. Intraoperative frozen section in a total of 4 (18.2%) patients always showed the correct histopathological diagnosis. No tumor-recurrence was observed in the 15 cases (68.6%) which underwent follow-up. CONCLUSIONS: In case of extratemporal neurinoma of the parotid gland, preparation of the facial nerve during surgery is often impossible, leading to segmental nerve resections. This decision, however, is made without proof for malignancy. In recognition of the biological behaviour of this entity the authors recommend that after tumor exploration a biopsy should be taken from the periphery of the tumor to exclude malignancy. After diagnosis of a neurinoma a nerve preserving (wait-and-see) approach appears justified.

[The value of hyperbaric oxygen therapy (HBO) in treatment of problem wounds in the area of plastic-reconstructive head and neck surgery]. / Der Stellenwert der hyperbaren Sauerstofftherapie (HBO) in der Behandlung von Problemwunden im Bereich der plastisch-rekonstruktiven Kopf-Hals-Chirurgie.

BACKGROUND: Hyperbaric oxygenation therapy is presently predominantly discussed in connection with sudden deafness and tinnitus. Amongst this ongoing controversy, the primary indications of this in the middle of the 20th century established therapy, especially in regard to problem wounds in the plastic-reconstructive surgery go mainly underrated. The present paper reviews the attention towards this area in plastic surgery. PATIENTS AND METHODS: Three typical cases (traumatic nasal tip reconstruction, wound ulceration after radiotherapy and lobe necrosis together with fistula following laryngopharyngectomy) are presented. RESULTS: Because of protracted and complicated wound healing HBO was applied in all three cases, eventually leading to very satisfying subconsequent wound-healing. In connection with these cases, the underlying problems and the effects of HBO are discussed. SUMMARIZING: The authors conclude, that HBO primary clinical application in treatment of problematic wound healing in head and neck appears to be very effective and helpful and should not be underrated whilst discussing this therapy in different contexts.