Polyhexanide-containing solution reduces ciliary beat frequency of human nasal epithelial cells in vitro.

In ENT, polyhexanide-containing solutions are used to treat nasal infections caused by multiresistant bacteria like methicillin-resistant Staphylococcus aureus. Many forms of commercial nasal solutions containing polyhexanide exist, such as gels or solutions for topical use. Data regarding the influence of polyhexanide on ciliary beat frequency (CBF) are lacking to date. We tested the CBF of nasal ciliated epithelial cells under the influence of a commercially available polyhexanide-containing solution (Lavasept(®) Concentrate) in a therapeutic concentration (0.04, 0.02%). In addition, we tested the concentrations of 0.1 and 0.01%. Cells were visualized with a phase contrast microscope, and the CBF was measured with the SAVA system's region of interest method. Ringer's solution and macrogol served as negative controls. A therapeutic concentration of Lavasept significantly reduced CBF in a time- and concentration-dependent manner. After 1 min, the CBF was reduced from 8.90 ± 1.64 to 5.00 ± 3.72 Hz with a concentration of 0.04% (p value = 0.001). After 10 min, all cilia stopped beating. After 5 min, a 0.02% solution of Lavasept concentrate decreased CBF significantly from 8.64 ± 1.71 to 3.30 ± 3.27 Hz (p value < 0.001). In conclusion, CBF of human nasal epithelia is significantly reduced with the use of the polyhexanide-containing solution Lavasept in some therapeutic concentrations. Due to our findings in this study, Lavasept should be used on ciliated mucosa only with caution and in a concentration of 0.02%.

EGFR-tyrosine kinase inhibitor treatment beyond progression in long-term Caucasian responders to erlotinib in advanced non-small cell lung cancer: a case-control study of overall survival.

INTRODUCTION: Some patients with advanced NSCLC show prolonged disease stabilization on treatment with an EGFR-tyrosine kinase inhibitor (TKI) such as erlotinib. It is not clear how to treat patients who progress after prolonged response to erlotinib. We hypothesized that TKI therapy beyond progression with added chemotherapy, radiotherapy or best supportive care may improve survival. PATIENTS AND METHODS: We retrospectively analyzed all NSCLC patients treated with erlotinib at our institutions since 2004who progressed after at least stable disease on erlotinib for at least 6 months. The first 16 patients did not receive further TKI treatment after progression (controls). The following 25 patients were treated with TKI beyond progression (TKI patients). Overall survival (OS) was analyzed for the whole population, a case-control analysis of pairs matched for gender, smoking status, and histology (n=28), and for patients with known EGFR mutation status (n=23). RESULTS: Treatment with TKI and chemotherapy was well tolerated. TKI-patients had a significantly longer OS from progression on TKI (case-control: median 14.5 vs. 2.0 months, HR 0.154) and longer OS from diagnosis of lung cancer (case-control: median 54.5 vs. 28.3 months, HR 0.474). An activating EGFR mutation was detected in 13 of the 23 patient tested (57%). Both among patients with and without detection of an activating EGFR mutation, those treated with erlotinib beyond progression had a longer survival. CONCLUSIONS: In our case-control analysis in long-term erlotinib responders, treatment with TKI beyond progression in addition to chemotherapy or radiotherapy was feasible and lead to prolonged overall survival.

[Internal jugular vein thrombosis as a paraneoplastic syndrome]. / Jugularvenenthrombose als paraneoplastisches Syndrom.

Thrombosis of the internal jugular vein is a rare form of deep vein thrombosis with potentially life threatening complications. We report on a 46-year-old male presenting with dysphagia and neck swelling. An extensive thrombosis of the internal jugular vein was found on ultrasound of the neck. An interdisciplinary workup revealed an occult gastric carcinoma. This case demonstrates that concomitant malignancies may contribute to a thrombosis of the internal jugular vein, which is then the primary symptom presented by the patient.

Impaired CD95 expression predisposes for recurrence in curatively resected colon carcinoma: clinical evidence for immunoselection and CD95L mediated control of minimal residual disease.

BACKGROUND: Loss of CD95 expression in tumour cells occurs frequently in colon carcinoma and may be associated with disease progression. On the other hand, neo-expression of CD95L in tumour cells may contribute to immune evasion. AIMS: We aimed at further exploring the functional role and prognostic significance of the CD95/CD95L death inducing system in colon carcinomas. PATIENTS AND METHODS: CD95 and CD95L expression was examined by immunohistochemistry in 128 R0 resected UICC (International Union against Cancer) stage II/III colon carcinomas and correlated with disease free survival. RESULTS: CD95 expression in tumour cells was observed in only 30 carcinomas (23.4%) whereas the others had at least a minor subpopulation of CD95 negative cells. Loss of CD95 in tumour cells was related to adverse prognosis in uni- and multivariate analysis (p = 0.046 and p = 0.036, respectively). Tumour infiltrating lymphocytes (TIL) were the major source of CD95L in colon carcinomas. CD95L+TIL were present in 83% of cases whereas CD95L was found in tumour cells in only 12% of cases. Moreover, a high rate of CD95L+TIL correlated with prolonged disease free survival in patients with UICC stage II (p = 0.05) but not in those with stage III. CONCLUSIONS: Loss of CD95 in tumour cells may be an independent prognostic factor in colon carcinomas. The CD95L counterattack is not a relevant feature in colon carcinoma but CD95L+TIL may contribute to tumour control in the early stages of the disease, exerting a concurrent selection pressure in the direction of CD95 abrogation/resistance.

[GI hemorrhage with fulminant shock induced by jejunal gastrointestinal stromal tumor (GIST) coincident with duodenal neuroendocrine carcinoma (NET) + neurofibromatosis (NF) -- case report and review of the literature]. / Hämorrhagischer Schock bei Doppelmalignom: Gastrointestinaler Stromatumor (GIST) und neuroendokrines Karzinom bei Morbus Recklinghausen.

BACKGROUND: The incidence of neuroendocrine tumors (NET) and of gastrointestinal stromal tumors (GIST) is 0.5 and 1 - 2 in 100,000; the prevalence of neurofibromatosis is 1 in 3000 live births in Western countries. CASE REPORT: A 43-year-old white woman with a six-month history of meleana, paleness, vertigo and fatigue was not referred to any gastrointestinal doctor for diagnostic work-up. Finally, she collapsed and was admitted to hospital because of an acute gastrointestinal bleeding. Endoscopically the source of bleeding could not be localized while blood in the duodenum and proximal jejunum was demonstrable. The source of bleeding could not be identified by endoscopy, CT scan or angiography. The patient developed a fulminant gastrointestinal hemorrhage with hemoglobin levels below 3.5 g %. An emergency laparotomy and pylorus-preventing Whipple operation was performed. Pathological studies showed a GIST with 3.5 cm diameter of the proximal jejunum which was the source of bleeding. Coincidentally a neuroendocrine carcinoma of the duodenum was found. CONCLUSION: This case is the first presentation of the coincidence of a neuroendocrine carcinoma of the duodenum with a jejunal bleeding gastrointestinal stromal tumor in neurofibromatosis type1 which led to hemorrhagic shock. In neurofibromatosis -- even if non-symptomatic -- the increased incidence of tumor needs to be considered.

Y chromosome detection of three-dimensional tissue-engineered skeletal muscle constructs in a syngeneic rat animal model.

Surgical reconstruction of muscle tissue lost by trauma or tumor ablation is limited by the lack of availability of functional native tissue substitution. Moreover, so far most inherited or acquired muscle diseases are lacking sufficient treatment, because only few alternatives exist to provide functional restoration of lost muscle tissues. Engineering those tissues and transplantation into sites of dysfunction may be an alternative approach and may allow replacement of such damaged or failing skeletal muscle tissues. Techniques attempting reconstruction of some human tissues and organs (tissue engineering) have been introduced into clinical practice recently. One major problem that previous transplantation studies were facing is the ability of detection of transplanted cells after integration. Using the Y chromosome in situ hybridization technique in a syngeneic rat model allows transplantation of cell constructs orthotopically, without manipulation of the cells, with no rejection or immunosuppression being implied, but providing a nondilutable genetic marker to identify transplanted cells. The purpose of our study was to create functional skeletal muscle tissue in vivo using the transplantation of primary myoblasts precultivated within a three-dimensional (3D) fibrin matrix and to determine the fate of the transplanted cells using the Y chromosome detection technique. 3D myoblast cultures were established derived from male donor rats and after 7 days of cultivation we performed an orthotopic transplantation of 3D cell constructs into a created muscle defect within the gracilis muscle of syngeneic female rats. Anti-desmin immunostaining and Y chromosome in situ hybridization indicated the survival and integration of transplanted male myoblasts into the female recipient animal, thus demonstrating the feasibility of this approach in tissue engineering and the research of cell transplantation in general.

CD95 (Fas/APO-1)/CD95L in the gastrointestinal tract: fictions and facts.

CD95 is a member of the tumor necrosis factor receptor family. It is constitutively expressed on the basolateral membrane of intestinal epithelial cells (IEC) and induces apoptosis when cross-linked by its natural ligand, CD95L. The significance of providing such a death-inducing mechanism in IEC is not yet clear. In recent years a multitude of studies have been published addressing the question of where and under which conditions CD95L is produced in the gut in the normal and neoplastic situation. Although some of these studies have considerably influenced our view on the role of the CD95/CD95L system, it appears necessary to critically review published data which are in part confusing and contradictory. To date compelling evidence of CD95L expression in untransformed IEC is lacking, and involvement of the CD95/CD95L system in the physiological epithelial cell turnover appears unlikely. Whereas CD95L is overexpressed in T-cells under inflammatory conditions, its significance for mucosal damage in inflammatory bowel diseases is obscured by possible redundancies in cell death mechanisms. Finally, recent data indicate that the intriguing CD95L counterattack concept in gastrointestinal tract cancer needs to be revised.

MedB-1, a human tumor cell line derived from a primary mediastinal large B-cell lymphoma.

Primary mediastinal B-cell lymphoma is a locally highly aggressive but poorly disseminating tumor composed of medium sized or large cells most probably of thymic medullary origin. It has a mature B-cell phenotype, typically lacks immunoglobulin expression and has variable defects in expression of HLA-molecules. We present here a cell line, MedB-1, derived from such a tumor. As is frequently found in mediastinal B-cell lymphomas in situ, MedB-1 is CD10(-), CD19(+), CD21(-), CD22(+), CD23(+), CD25(-), CD37(+), CD38(-), CD39(+), CD40(+), CD54(+), CD95(+). Like the parental tumor, MedB-1 lacks HLA-A,B,C alpha-chains and beta(2)microglobulin and expresses HLA-D molecules at decreased levels. Both parental tumor and MedB-1 cells are clonally related as shown by immunoglobulin heavy chain gene rearrangement analysis. Unlike the parental tumor tissue, the MedB-1 cell line cytoplasmically expresses IgG/kappa in a very small subset of cells under standard culture conditions. MedB-1 does not contain any Epstein-Barr virus DNA. In a tissue adhesion assay MedB-1 cells showed an extensive binding to the medullary region of normal thymus. Altogether, MedB-1 is a suitable tool for functional and molecular analysis of this distinct lymphoma entity.

Differential and mutually exclusive expression of CD95 and CD95 ligand in epithelia of normal pancreas and chronic pancreatitis.

Acinar regression in chronic pancreatitis may be due to immune attack in parenchymal areas neoexpressing HLA-DR molecules. CD4+Th1 cytotoxic T cells induce apoptosis of their targets via oligomerizing CD95 (APO-1/Fas) death receptors on target cells by their CD95 ligand (CD95L). We determined the expression of CD95 and CD95L in epithelia of normal and chronically inflamed pancreatic tissues. We applied RT-PCR and Western blotting for CD95L expression profiles, serial frozen section immunohistochemistry to detect CD95, CD95L, and HLA-DR molecules, CD3, CD4, CD11c, and S-100 protein (S100p). Normal pancreases and chronic pancreatitis contain CD95L message and protein. Immunohistochemistry revealed a mutually exclusive expression of CD95 and CD95L. Physiologically, acini were CD95-/CD95L+, ducts were CD95-/CD95L-, and islets were CD95-/CD95L+. In areas of lymphohistiocytic infiltration, mainly consisting of CD3+CD4+ T cells and CD11c+, CD4+/-, S100p+ interstitial dendritic cells, and in areas of initial fibrosis, acini and ducts were HLA-DR+, acini CD95+/CD95L-, and ducts CD95+/CD95L-. Islet cells were CD95-/CD95L+ in both conditions. IFNgamma levels in protein lysates, as measured by an immunoassay, were significantly higher in chronic pancreatitis than in normal pancreas (p < 0.0003). In vitro, IFNgamma down-modulated CD95L message and protein in ASPC1 and BxPc3 pancreatic carcinoma cells. In conclusion, pancreatic epithelia differentially express CD95 and CD95L in a mutually exclusive manner. In chronic pancreatitis the CD95-/CD95L+ status is conserved in islet cells even in the vicinity of lymphohistiocytic infiltrates, whereas it is lost in acini coexpressing HLA-DR. As a potential consequence, and possibly triggered by local release of IFNgamma, CD4-Th1 cells may cognately interact with and successfully attack exocrine cells by triggering CD95 on their target without being killed by epithelial, CD95L-mediated, counterattack.

CD95 ligand (CD95L) immunohistochemistry: a critical study on 12 antibodies.

In recent years, some studies on the expression of CD95(Fas/APO-1) ligand (CD95L) in tissues or cells raised concerns about the specificity of the antibodies used. We therefore tested 12 CD95L antibodies for their reliability in immunocyto/histochemistry by (i) staining CD95L-transfected and control CV-1/EBNA cells and (ii) comparing staining patterns in immunohistochemically labeled tissue sections with the localization of CD95L+ cells in in situ hybridization. While G247-4, NOK-1, NOK-2, 4H9, and MIKE-1 stained CD95L-transfected cells and did not significantly bind to controls, G247-4 was the only antibody giving satisfying signals in tissue sections perfectly matching the distribution of CD95L+ cells by in situ hybridization. MAb 33, C-20, and N-20 comparably stained both transfected and control cells and showed considerable background or falsely positive staining in sections. MIKE-2, 8B8, A11, and 4A5 did not or only very faintly bind to either cells and, thus, were not tested on sections. We conclude that G247-4 is the only tested antibody that is recommendable for immunohistochemistry.

Rhinolith of the nasal septum.

We report an unusual case of rhinolith in the nasal septum in an 11-year-old girl. The rhinolith was detected on X-radiographs made for the planning of an orthodontic treatment. There were no symptoms like nasal obstruction, chronic infection or epistaxis in the young patient. The histopathologic examination after surgical removal showed hyaline cartilage, local fibrosis and pronounced hemosiderosis, indicating possible prior bleeding. Therefore, an endogenic etiology of the intraseptal rhinolith, e.g. a prior trauma of the nasal septum, is assumed. A review of the literature is included.

Expression and function of death receptors and their natural ligands in the intestine.

The tumor necrosis factor receptor (TNFR) family is a still-growing group of homologous transmembrane proteins, some of which bear an intracellular "death domain" and are able to directly mediate apoptosis. Apoptosis is induced upon trimerization of the receptors by their natural ligands' constituting the complementary TNF family. The best-characterized apoptosis-mediating TNFR family member is CD95 (APO-1/Fas). CD95 is functionally expressed on the basolateral surface of colonic epithelial cells regardless of their position along the crypt axis. The biological significance of this CD95 expression in the gut, however, is still under discussion. Although it is unlikely that the CD95/CD95L system is involved in the physiologic regeneration of the intestinal epithelium, this system may play an important role in the pathogenesis of inflammatory bowel diseases. In contrast to the normal epithelium, colon carcinoma cell lines are mostly resistant to CD95-induced apoptosis. The detection of CD95L expression in colon carcinoma cell lines has led to the concept of carcinomas as "immunoprivileged sites," where invading immune cells are killed by CD95L-expressing tumor cells. A more recently described member of the TNF family is TRAIL, which is also able to induce apoptosis. As yet, four TRAIL receptors have been cloned, two of which (TRAIL-R1 and 2) bear a death domain and mediate apoptosis, whereas two others (TRAIL-R3 and 4) lack (functional) death domains and are supposed to act as decoy receptors. Because many tumor cell lines in vitro are sensitive to TRAIL-induced apoptosis while their normal counterparts are not, TRAIL is currently under discussion as a possible anticancer therapeutic agent.

Mediastinal B-cell lymphoma: a study of its histomorphologic spectrum based on 109 cases.

Mediastinal B-cell lymphoma (MBL) is a distinct variant of aggressive non-Hodgkin's lymphoma with characteristic clinical and biological features but less well-defined histomorphology. We reevaluated 124 biopsy specimens from 109 MBL patients of an Italian/French/German retrospective clinical study. MBL was primarily diagnosed on clinical and histological grounds in conjunction with the detection of CD20 expression by immunohistology. Cytologically, MBL features limited intralesional but considerable interindividual cytological diversity, ranging from medium-sized to very large, atypical cells. Sclerosis and necrosis are restricted to extrathymic and extranodal sites of involvement, predominantly the lung, as is angioinvasion, which predominantly affects larger vessels. The medium-sized and the large cell variants resemble marginal zone lymphoma variants, whereas the very large cell variant of MBL has not so far been found to have any extramediastinal counterpart. We conclude that MBL displays a broad morphological spectrum covering more than is implied by the term "diffuse large cell lymphoma." Because statistical analysis of cytological and histological criteria failed to correlate with prognosis in this comprehensive group of patients, we think it inadvisable further to subclassify MBL.

CD95 ligand (CD95L) in normal human lymphoid tissues: a subset of plasma cells are prominent producers of CD95L.

CD95(Fas/APO-1)-ligand (CD95L) mediates apoptosis by trimerization of the CD95 receptor on the surface of sensitive cells. In vitro studies have shown CD95L expression mainly by activated T cells and suggested a role for CD95L in the regulation of immune responses. Little is known, however, about the cellular distribution of CD95L in situ in the normal human immune system. We investigated CD95L expression in tissue sections of the thymus, lymph node, spleen, tonsil, and gastrointestinal tract using in situ hybridization and two monoclonal antibodies. In all these organs, cells expressing CD95L message and protein were scarce and comprised scattered lymphocytes, rare nonlymphoid cells, and a subset of epithelioid endothelial cells. Surprisingly, a subset of plasma cells turned out to be the most prominent producers of CD95L, matching the reports on CD95L in myeloma cells. CD95L+ plasma cells were most numerous in the mucosa-associated lymphoid tissue. This also applied to acquired mucosa-associated lymphoid tissue in chronic gastritis in which CD95L+ plasma cells were found scattered in the lamina propria. Our data suggest that plasma cells as yet may be neglected modulators of immune responses.

Pathogenesis of primary biliary cirrhosis: CD95-induced apoptosis at last?

Apoptosis is a basic mechanism involved both in maintaining tissue homeostasis by elimination of senescent or potentially harmful cells and in the regulation of immune responses. If not properly regulated, however, it may lead to serious tissue damage. CD95(Fas/APO-1) is a surface receptor that mediates apoptosis upon oligomerization by its ligand, CD95L. The CD95/CD95L-system is one of the major effectors of cytotoxicity in inflammation with implications for both the prevention and the pathogenesis of autoimmune diseases. In primary biliary cirrhosis (PBC), an autoimmune disease, apoptosis has been repeatedly suspected to be the mechanism leading to progressive destruction of bile ducts. The role of apoptosis and its possible molecular inducers in PBC are discussed.

No evidence for cancer-related CD44 splice variants in primary and metastatic colorectal cancer.

The expression of alternatively spliced CD44 adhesion molecules has been implicated in the pathogenesis and metastasis of colorectal cancer. Using a new set of primers for exon-specific reverse transcription-polymerase chain reaction (RT-PCR) we delineated the exact exon composition of CD44 mRNAs in normal colorectal mucosa, including isolated colonic crypts, in colorectal carcinomas and in their hepatic metastases. In addition, the surface expression of CD44 isoforms was analysed by immunohistochemistry. We identified by RT-PCR eight variant transcripts expressed in colorectal carcinomas and their metastases, but also constitutively in normal colorectal epithelia. In the normal colorectal epithelium, the surface expression of CD44 standard and variant molecules was restricted to proliferating cells at the bottom of the crypts. Despite expression of these transcripts in colorectal cancers and their metastases, monoclonal antibodies specific for standard or variant epitopes encoded by exons v5 and v6 stained only a few neoplastic lesions. These data point to a differentiation-specific CD44 expression and splicing pattern in proliferating colorectal epithelia. However, they do not support a cancer- or metastasis-specific CD44 splicing pattern. Instead, cell surface availability of CD44 epitopes was reduced rather than increased in primary tumours and particularly in liver metastases.

Radiocontrast-induced DNA fragmentation of renal tubular cells in vitro: role of hypertonicity.

BACKGROUND: Radiocontrast-induced nephropathy is a clinically important complication of invasive cardiological procedures. It has been associated with DNA fragmentation of renal tubular cells, which is a hallmark feature of programmed cell death (apoptosis). We investigated the mechanism of this DNA fragmentation in an in vitro model of radiocontrast cytotoxicity on renal epithelial cells. METHODS: Madin Darby canine kidney (MDCK) cell monolayers were incubated (for 2-8 h) with isoiodine doses (37-111 mg iodine/ml) of the highly hyperosmolal, ionic radiocontrast agent diatrizoate or of the less hyperosmolal, non-ionic substance iopamidol. Mannitol, urea, and NaCl control media of corresponding hyperosmolality were used to evaluate the contribution of hypertonicity, hyperosmolality and/or ionic strength to radiocontrast toxicity. DNA fragmentation was assessed using fluorescence-activated cell sorting (FACS), agarose gel electrophoresis and terminal deoxynucleotidyl transferase-mediated deoxyuridine nick end labelling (TUNEL), cell morphology was analysed in Giemsa-stained cytospins. RESULTS: Diatrizoate induced concentration- and time-dependent DNA fragmentation of MDCK cells which was associated with morphological signs of apoptosis. Cycloheximide (1 microg/ml) did not prevent diatrizoate-induced DNA fragmentation, indicating that it is not dependent on protein synthesis. Diatrizoate-mediated cell death was associated with cell detachment from the tissue culture matrix. However, the DNA fragmentation is not a consequence of cell detachment since the prevention of cell attachment on agarose-coated dishes induced significantly less DNA fragmentation than diatrizoate. Iopamidol caused no detectable DNA breakdown. In contrast, hypertonic mannitol and sodium chloride, but not hyperosmolal urea, induced DNA fragmentation in MDCK cells, albeit less than diatrizoate. CONCLUSIONS: The DNA fragmentation of MDCK cells induced by diatrizoate is related to its hypertonicity in this in vitro model of radiocontrast cytotoxicity. Nuclear disintegration with subsequent cell death may contribute to the pathophysiology of radiocontrast-induced nephropathy, particularly in the hypertonic/hypoxic environment of the renal medulla. The present results underscore the importance of avoiding hyperosmolal urine states in patients at high risk of radiocontrast-induced nephropathy.