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11.
Differences of E-cadherin expression levels and patterns in primary and metastatic human lung cancer 总被引:6,自引:0,他引:6
Malte Böhm Baldur Totzeck Walter Birchmeier Ilse Wieland 《Clinical & experimental metastasis》1994,12(1):55-62
Normal lung epithelium and 52 lung carcinomas obtained at surgical resection were examined by immunofluorescence for their expression levels and patterns of the calcium-dependent intercellular adhesion molecule E-cadherin. In dysplastic lung tissue and in well-differentiated squamous cell and adenocarcinomas, expression of E-cadherin was confined to the lateral cell border, similar to the expression level and pattern of normal lung tissue. The E-cadherin level was reduced and expression pattern was spotty or diffuse in moderately and poorly differentiated squamous cell and in small cell carcinomas of the lung. Most metastases resected also had a reduced level and an altered pattern of E-cadherin expression. In contrast, no such correlation was found in adenocarcinomas of the lung. This indicates that different cellular mechanisms are responsible in the progression of squamous cell carcinomas and adenocarcinomas of the lung. 相似文献
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Scl-70 is the major antigen recognised by autoantibodies in the sera of patients with systemic sclerosis (SSc). The autoantibodies that specifically react with Scl-70 are highly characteristic of the disease and represent valuable markers for the diagnosis of SSc. We describe a novel strategy for cloning autoantibody fragments starting with a small blood sample from an SSc patient. B cells isolated from the collected peripheral blood mononuclear cells (PBMCs) were cultured in vitro using the EL4-B5 system. Anti-Scl-70 IgG-producing cells were pooled for RNA preparation followed by the generation of phagemid libraries of approximately 10(7) independent single-chain Fvs (scFvs). The screening of these libraries by phage display allowed us to isolate four anti-Scl-70 scFvs following three rounds of biopanning. About 10 times more starting blood material was needed to generate scFv libraries of similar size from PBMCs of an SSc patient and only two anti-Scl-70 scFvs were isolated after three rounds of phage selection. Together, this work shows that functional autoantibody fragments can be advantageously cloned after in vitro expansion of B cells. The isolated anti-Scl-70 autoantibody fragments represent useful tools for calibrating SSc diagnostic assays. 相似文献
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OBJECTIVE: To investigate the effect of IL-10 on the inducibility of human beta-defensin 2 (hBD-2) in human peripheral blood cells. METHODS: Peripheral blood samples were collected from 22 healthy individuals and co-cultured with 0 ng/ml lipopolysaccharide (LPS), 100 ng/ml LPS, 10 ng/ml IL-10, or 100 ng/ml LPS plus 10 ng/ml IL-10 at 37 degree for 6 h. Total RNA was extracted from peripheral blood cells and the mRNA level of hBD-2 was detected by relative quantitative real-time PCR.. RESULT: No detectable level of hBD-2 mRNA was found in normal peripheral blood cells with stimulation of 0 ng/ml LPS or 10 ng/ml IL-10. The mRNA level of hBD-2 was increased to 166.9 +/- 35.14 after 100 ng/ml LPS challenge, while the mRNA level of hBD-2 was decreased to 30.40 +/- 9.18 after the co-stimulation of 100 ng/ml LPS plus 10 ng/ml IL-10; which was significantly lower than that with LPS alone (P<0.05). CONCLUSION: The expression of hBD-2 gene can be induced by LPS.IL-10 inhibits the inducible expression of hBD-2. 相似文献
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Malte Buchholz Hans A Kestler Andrea Bauer Wolfgang B?ck Bettina Rau Gerhard Leder Wolfgang Kratzer Martin Bommer Aldo Scarpa Martin K Schilling Guido Adler J?rg D Hoheisel Thomas M Gress 《Clinical cancer research》2005,11(22):8048-8054
PURPOSE: Malignant tumors of the pancreas are frequently indistinguishable from inflammatory tumors arising in the context of a chronic pancreatitis with the use of conventional imaging techniques. Thus, cytologic analysis of cells obtained by abdominal ultrasound, computed tomography, or endoscopic ultrasound-guided fine needle aspiration biopsy is required for diagnosis. However, the reliability of cytologic analyses of pancreatic fine needle aspirates remains unsatisfactory, with a diagnostic accuracy of < or =80%. The purpose of the current study was therefore to develop a novel diagnostic approach based on expression profiling of biopsy material using a specialized diagnostic cDNA array. EXPERIMENTAL DESIGN: Previous gene expression profiling studies were reevaluated to design a 558-feature diagnostic array. Minimal amounts of residual material from pancreatic cytology samples as well as surgically resected tumor and control tissue specimens were analyzed using the diagnostic array and a newly developed statistical classification system. RESULTS AND CONCLUSIONS: Our diagnostic approach resulted in 95% accurate differentiation between ductal adenocarcinomas and nonmalignant tumors of the pancreas. The diagnostic array, in conjunction with conventional diagnostic procedures, is thus suitable to significantly improve the reliability of pancreatic cancer diagnostics and can be expected to become a valuable new tool in the routine workup of suspect masses in the pancreas. 相似文献
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The film thickness plays an important role in the performance of materials applicable to different technologies including chemical sensors, catalysis and/or energy materials. The relationship between the surface and volume of the functional layers is key to high performance evaluations. Here we demonstrate the thermophoretic deposition of different thicknesses of the functional layers designed using flame combustion of tin 2-ethylhexanoate dissolved in xylene, and measurement of thickness by scanning electron microscopy and focused ion beam. The parameters such as spray fluid concentration (differing Sn2+ content), substrate-nozzle distance and time of the spray were considered to investigate the layer growth. The results showed ≈ 23, 124 and 161 μm thickness of the SnO2 layer after flame spray of 0.1, 0.5 M and 1.0 M tin 2-EHA-Xylene solutions for 1200 s. While Sn2+ concentration was 0.5 M for all the flame sprays, the substrates placed at 250, 220 and 200 mm from the flame nozzle had layer thicknesses of 113, 116 and 132 µm, respectively. Spray time dependent thickness growth showed a linear increase from 8.5 to 152.1 µm when the substrates were flame sprayed for 30 s to 1200 s using 0.5 M tin 2-EHA-Xylene solutions. Changing the dispersion oxygen flow (3–7 L/min) had almost no effect on layer thickness. Layers fabricated were compared to a model found in literature, which seems to describe the thickness well in the domain of varied parameters. It turned out that primary particle size deposited on the substrate can be tuned without altering the layer thickness and with little effect on porosity. Applications depending on porosity, such as catalysis or gas sensing, can benefit from tuning the layer thickness and primary particle size. 相似文献
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Prof. Dr. med. Christoph Skudlik Johannes Geier Swen Malte John 《Der Hautarzt; Zeitschrift für Dermatologie, Venerologie, und verwandte Gebiete》2014,65(11):983-997
In clinical practice occupational skin diseases usually present as hand dermatitis. Occupationally acquired contact allergies are of eminent relevance in many work place products e.g. skin care products, dyes and paints, epoxy resins or protective gloves. However, not infrequently, a range of other dermatoses of different etiology and localization can be occupationally induced and, at least in Germany, thus be medically treated and—if necessary—compensated for with full coverage by the statutory employers’ liability insurance. Examples regarding non-eczematous skin diseases triggered by external factors are psoriatic lesions, cutaneous type-1-allergies, occupationally acquired infections, and dermatoses in other localizations which are occupationally exposed to irritant influences (e.g. feet in workers wearing occlusive safety boots). Moreover, outdoor workers deserve specific attention by the dermatologist if squamous cell carcinomas including precursor lesions like actinic keratoses or Bowen disease have occurred. In Germany, recently the scientific advisory committee to the Ministry of Labor has recommended including these skin cancers caused by occupational solar UV exposure in the national list of occupational diseases. The framework for dermatological preventive care of occupationally-induced inflammatory dermatoses has been continuously improved in the last years. The aim is to reach a similar level of care and preventive measures for patients with occupational skin cancer, including primary preventive workers’ education. 相似文献