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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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Plasma B-type natriuretic peptide (BNP) concentration was evaluated in end-stage renal disease patients to verify if measurements before or after the session could furnish different information. BNP levels in plasma from 52 hemodialysis (HD) patients were measured both before and after the first session of the week. Echocardiographic studies were also performed and patients were followed over a period of 28 months. BNP removal from plasma was influenced by equilibrated Kt/V and patient characteristics. Initial plasma BNP concentration was correlated both with cardiac systolic function (LVEF) and mortality rate, independent of blood sample timing (before or after HD). A relative risk of death of 2.67 was found for plasma BNP levels above 335 pg/mL or 232 pg/mL, before and after HD, respectively. Higher BNP levels were observed in patients with higher burden of comorbidity, as measured by the Charlson Comorbidity Index; however, statistical significance was obtained only for BNP measured before HD. In conclusion, measurement of plasma BNP could give a valuable risk stratification of HD patients while cutting costs, by confining echocardiographic studies only to cases with BNP levels above the established cutoff values.  相似文献   
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OBJECTIVES: To evaluate simultaneously several possible risk factors for blood bank specimen hemolysis. METHODS: This was a prospective cohort study of emergency department and labor and delivery patients to estimate the effect of various factors on the risk of blood bank specimen hemolysis. Study variables included patient demographics, type and gauge of needle or catheter, anatomic location of venipuncture, and patient care area. Hemolysis was determined by blood bank laboratory technicians. Cox proportional hazards multivariate regression modeling was performed to estimate the adjusted relative risks for hemolysis. RESULTS: Of the 605 subjects with complete data, 194 (32.1%) subjects had blood specimens drawn directly with a steel needle, and 411 (69.1%) had specimens drawn through a Vialon (BD Medical Systems, Inc., Sandy, UT) intravenous (IV) angiocatheter. The overall risk of hemolysis for all was 7%, 10% for Vialon IV angiocatheters and 1.5% for steel needles. In the multivariate analysis, the factors most closely associated with hemolysis were the use of Vialon IV catheters and sampling from an anatomic site other than the antecubital area. CONCLUSIONS: Blood bank specimens drawn from Vialon IV catheters (particularly smaller gauge catheters) and from veins outside the antecubital area are at significantly increased risk to hemolyze.  相似文献   
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目的:流行病学调查结果显示,地方性氟中毒与甲状腺肿的流行有很大的重叠性。探讨氟化钠对原代培养猪甲状腺细胞及甲状腺过氧化物酶活性的影响。方法:实验于2006-10/2007-05在辽宁医学院科学实验室中心完成。①实验方法:在猪死亡1h内取其甲状腺组织,去除甲状腺组织包膜及外层活性差的组织,选取中央活性高的部位,剪成1mm3组织块,用胰蛋白酶、胶原酶Ⅳ消化分离,得到含猪甲状腺细胞的消化液,沉淀悬于含体积分数为0.15的胎牛血清、1U/L牛促甲状腺素、80万U/L庆大霉素的F12培养基中,过滤,调整细胞浓度至5×105L-1,接种培养,每3d更换培养液。常规培养48h的猪甲状腺细胞接种于96孔培养板,按氟化钠终浓度不同分为0,40,80,160mg/L组。②实验评估:染毒48h后,采用噻唑蓝法测定细胞存活量,采用改良愈创木酚法测定甲状腺过氧化物酶活性。结果:①氟化钠对原代培养猪甲状腺细胞存活量的影响:与0mg/L氟化钠比较,40mg/L氟化钠染毒后猪甲状腺细胞的存活量基本相似;80,160mg/L氟化钠染毒后猪甲状腺细胞的存活量均明显下降(P<0.01)。②氟化钠对甲状腺过氧化物酶活性的影响:与0mg/L氟化钠比较,40,80,160mg/L氟化钠染毒后的甲状腺过氧化物酶活性均明显下降(P<0.01),呈剂量-效应关系。结论:氟化钠对原代培养的猪甲状腺细胞及甲状腺过氧化物酶活性均具有抑制作用。  相似文献   
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