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81.
Head and neck squamous cell carcinoma (HNSCC) is a very aggressive tumour arising from the epithelial lining of the upper aerodigestive tract. The precise mechanisms involved in the pathogenesis of HNSCC have not been elucidated. Previous studies observed aberrant HLA expression patterns on HNSCC tumour cells and this study focused on the allelic polymorphism of HLA genes and the MHC class I chain related gene A (MICA) and HNSCC. We investigated whether associations with HLA and/or MIC alleles or haplotypes are involved in the pathogenesis of HNSCC and could explain the observed HLA expression patterns. Patients and controls were typed for HLA-A, HLA-B, HLA-C, HLA-DRB1 and HLA-DQB1 with sequence specific priming (SSP), supplemented with sequencing based typing (SBT). MICA allelic polymorphism was included and MICA allele assignment was based upon the combination of high resolution SBT of exons 2-4 in combination with repeat analysis and nucleotide polymorphism of exon 5. HLA-B *35 (p=0.014, OR=0.31) and HLA-B *40 (p=0.013, OR=2.9) were significantly associated in respectively the metastasized patients and the oral cavity patients. In addition, the HLA-B *40-DRB1 *13 haplotype (p=0.016, OR=4.1) was more often observed in the oral cavity patient group. The biological significance of the prevalence of specific HLA haplotypes in patients with oral cavity HNSCC and metastasizing HNSCC requires further investigation.  相似文献   
82.
BACKGROUND: Optimal management in patients with umbilical hernias and liver cirrhosis with ascites is still under debate. The objective of this study was to compare the outcome in our series of operative versus conservative treatment of these patients. METHODS: In the period between 1990 and 2004, 34 patients with an umbilical hernia combined with liver cirrhosis and ascites were identified from our hospital database. In 17 patients, treatment consisted of elective hernia repair, and 13 were managed conservatively. Four patients underwent hernia repair during liver transplantation. RESULTS: Elective hernia repair was successful without complications and recurrence in 12 out of 17 patients. Complications occurred in 3 of these 17 patients, consisting of wound-related problems and recurrence in 4 out 17. Success rate of the initial conservative management was only 23%; hospital admittance for incarcerations occurred in 10 of 13 patients, of which 6 required hernia repair in an emergency setting. Two patients of the initially conservative managed group died from complications of the umbilical hernia. In the 4 patients that underwent hernia correction during liver transplantation, no complications occurred and 1 patient had a recurrence. CONCLUSIONS: Conservative management of umbilical hernias in patients with liver cirrhosis and ascites leads to a high rate of incarcerations with subsequent hernia repair in an emergency setting, whereas elective repair can be performed with less morbidity and is therefore advocated.  相似文献   
83.
Mistaken identity of widely used esophageal adenocarcinoma cell line TE-7   总被引:2,自引:0,他引:2  
Cancer of the esophagus is the seventh leading cause of cancer death worldwide. Esophageal carcinoma cell lines are useful models to study the biological and genetic alterations in these tumors. An important prerequisite of cell line research is the authenticity of the used cell lines because the mistaken identity of a cell line may lead to invalid conclusions. Estimates indicate that up to 36% of the cell lines are of a different origin or species than supposed. The TE series, established in late 1970s and early 1980s by Nishihira et al. in Japan, is one of the first esophageal cancer cell line series that was used throughout the world. Fourteen TE cell lines were derived from human esophageal squamous cell carcinomas and one, TE-7, was derived from a primary esophageal adenocarcinoma. In numerous studies, this TE-7 cell line was used as a model for esophageal adenocarcinoma because it is one of the few esophageal adenocarcinoma cell lines existing. We investigated the authenticity of the esophageal adenocarcinoma cell line TE-7 by xenografting, short tandem repeat profiling, mutation analyses, and array-comparative genomic hybridization and showed that cell line TE-7 shared the same genotype as the esophageal squamous cell carcinoma cell lines TE-2, TE-3, TE-12, and TE-13. In addition, for more than a decade, independent TE-7 cultures from Japan, United States, United Kingdom, France, and the Netherlands had the same genotype. Examination of the TE-7 cell line xenograft revealed the histology of a squamous cell carcinoma. We conclude that the TE-7 cell line, used in several laboratories throughout the world, is not an adenocarcinoma, but a squamous cell carcinoma cell line. Furthermore, the cell lines TE-2, TE-3, TE-7, TE-12, and TE-13 should be regarded as one single squamous cell carcinoma cell line.  相似文献   
84.
BACKGROUND AND OBJECTIVES: Both ultrasound (US) and computed tomography (CT) can be used to detect supraclavicular lymph node metastases. Aim was to compare US, US plus fine-needle aspiration (US-FNA), CT, US + CT, and US-FNA + CT for the detection of these metastases in esophageal or gastric cardia cancer patients. METHODS: Between 1994 and 2004, 567 patients underwent US and CT for esophageal or gastric cardia cancer staging. Gold standard was postoperative detection of lymph nodes in the resected specimen, FNA, or a radiological result with follow-up. RESULTS: Sensitivities of US (75%), US-FNA (72%), US + CT (80%), and US-FNA + CT (79%) were higher than sensitivity of CT alone (25%) (P < 0.001). Specificities were high for US-FNA (100%), CT (99%), and US-FNA + CT (99%), whereas those of US alone (91%) and US + CT (91%) were lower (P < 0.001). In 4/65 (6%) patients with true-positive malignant lymph nodes, CT was positive with US and/or US-FNA being negative. However, in 36/65 (55%) patients, US and/or US-FNA were positive with CT being negative. CONCLUSION: US-FNA seems the preferred diagnostic modality for the detection of supraclavicular lymph node metastases in patients with esophageal or gastric cardia cancer. Sensitivity of metastases detection only slightly improves if US-FNA is combined with CT. A prospective, comparative study is however needed.  相似文献   
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Mean platelet survival and turnover were simultaneously determined with autologous 111In-labeled platelets (111In-AP) and homologous 51Cr- labeled platelets (51Cr-HP) in ten patients with chronic immune thrombocytopenic purpura (ITP). In vivo redistribution of the 111In-AP was quantitated with a scintillation camera and computer-assisted image analysis. The patients were divided into two groups: those with splenic platelet sequestration (spleen-liver 111In activity ratio greater than 1.4), and those with diffuse sequestration in the reticuloendothelial system. The latter patients had more severe ITP reflected by pronounced thrombocytopenia, decreased platelet turnover, and prominent early hepatic platelet sequestration. Mean platelet life span estimated with 51Cr-HP was consistently shorter than that of 111In-AP. Platelet turnover determined with 51Cr-HP was thus over-estimated. The difference in results with the two isotope labels was apparently due to greater in vivo elution of 51Cr. Although the limitations of the techniques should be taken into account, these findings indicate that platelet turnover is not always normal or increased in ITP, but is low in severe disease. We suggest that this may be ascribed to damage to megakaryocytes by antiplatelet antibody. The physical characteristics in 111In clearly make this radionuclide superior to 51Cr for the study of platelet kinetics in ITP.  相似文献   
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88.
Background  Pemphigus is an autoimmune disease characterized by the formation of intra-epidermal blisters. Patients develop auto-antibodies against desmoglein 1 and 3 proteins and induce acantholysis.
Objective  This work addresses the issue of whether the Fas pathway mediates acantholysis. Furthermore, the possible suppliers of the Fas pathway were investigated.
Methods  Seventeen biopsies of pemphigus patients were studied by haematoxylin and eosin staining, and apoptosis was defined by TUNEL. The expression of Fas, FasL and caspase 3 was studied by in situ hybridization and immunohistochemistry. Cell infiltrates were studied by immunofluorescence with monoclonal anti-CD3, CD4, CD8, CD19 and CD69.
Results  All of the biopsies showed intra-epidermal blisters, acantholytic cells and inflammatory infiltrates. The blisters expressed Fas, FasL and caspase 3. Cell infiltrates were composed of CD8 and a few CD4+CD69+ cells. Additionally, CD19+ cells were detected. Interestingly, the Fas expression was increased in acantholytic cells and perilesional keratinocytes. Incidentally, these cells exhibited apoptotic features. Interestingly, the CD8 cells expressed FasL.
Conclusion  This paper presents the morphological evidence that apoptosis and acantholysis are linked. Therefore, the Fas pathway is associated with CD8 cells in pemphigus lesions.

Conflicts of interest


None declared.  相似文献   
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