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81.
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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Low plasma levels of antithrombin III due to excessive urinary loss are thought to be the cause of thrombotic complications in patients with the nephrotic syndrome. To see whether protein C (PC), another antithrombotic protein, is also reduced in plasma by the same mechanism, plasma and urinary protein C were determined in 24 patients with nephrotic syndrome and no thrombotic complication, and compared to plasma and urinary antithrombin III. Twenty patients (83%) had high plasma levels of protein C activity (mean +/- SD 157 +/- 41 U/dl) and antigen (158 +/- 41). Even though measurable amounts of PC antigen were found in the urines of all but two patients the urinary loss of protein C relative to its plasma concentration was about 40 times lower than that of antithrombin III. High protein C might help to counteract hypercoagulability in nephrotic syndrome.  相似文献   
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AimTo compare safety and efficacy of a bipolar vessel sealing system (BVSS) to the conventional technique in axillary node dissection.Methods116 women with breast cancer were randomized to conventional node dissection surgical technique (control; n = 58) by scalpel and monopolar cautery or using an electrothermal BVSS (study group; n = 58).ResultsThe median (range) total volume of fluid collected by drain and aspirations was 305 (30–1420) mL in the study group and 335 (80–1070) mL in the control group (p = 0.325). The median (range) total volume of lymph collected by percutaneous aspirations was 207.5 (40–1050) mL in the study group and 505 (270–705) mL in the control group (p = 0.010). The incidence of seroma was similar in both groups (p = 0.845). The axillary drain was removed earlier in the study group than in controls (p = 0.046).ConclusionThe use of a BVSS offers marginal advantages when compared to the conventional technique.  相似文献   
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The histologic features of thymuses from three patients who underwent thymectomy for acute lymphoblastic leukemia or lymphoblastic lymphoma in complete clinical remission are described. The thymuses from all three patients were fibrotic with a variability in the appearance of the lobules. Some of the lobules consisted predominantly of epithelial cells with small numbers of mature appearing lymphocytes, while other lobules were expanded and composed predominantly of cells having morphological features of immature lymphoid cells consistent with residual or recurrent disease.  相似文献   
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GOALS: The purpose of this review is to look at the evidence presented in the literature on the immunoexpression of p27 in cancers of the gastrointestinal tract and liver. BACKGROUND: Cell cycle proteins have been shown to play an important role in the oncogenesis of many tumors. Several of these proteins have been examined in concert and in isolation, and some have been put forward as putative tumor markers. p27, which is an important inhibitory protein in the cell cycle and belonging to a group of cyclin-dependent kinase inhibitors, has also been studied in several malignancies, most notably breast, lung, bladder, and prostate cancers. Considerable work has also been done on the expression of this protein in cancers occurring within the gastrointestinal tract. RESULTS: Cancers occurring in the major sites of the gastrointestinal tract (esophagus, stomach, and colorectum) and liver show a similar pattern with regard to p27 protein levels. p27 emerges as a statistically significant predictor of survival and tumor behavior. It has been suggested that p27 loss occurs early in the carcinogenesis process, with dysplastic epithelium having decreased expression. The more aggressive, metastasizing cancers tend to lack p27 expression as well. Some studies have also invoked the subcellular localization of p27 (cytoplasmic versus nuclear) as also being of prognostic value. CONCLUSION: Therefore, in gastrointestinal and hepatic cancers, low p27 expression is regarded as an important adverse prognostic factor.  相似文献   
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We investigated 42 plasmas prepared at different centrifugation speeds with three activated protein C (APC) resistance methods. The APC ratio for fresh platelet-poor plasma declined significantly after freezing and thawing. This effect was more evident with the original method (average reduction 11.3%) than with either the home-made (3.8%) or the modified method (3.2%). No significant decrease in the APC ratio was observed after freezing and thawing of platelet-free plasmas from the same patients. When frozen platelet-poor plasma was centrifuged at high speed after thawing and before testing, there was no significant decrease in the APC ratio, in comparison with fresh platelet-poor plasma using the home-made and modified methods.  相似文献   
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