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Background Real-time quantitative polymerase chain reaction (qPCR) may prove to be a sensitive technique by which to evaluate potential tumor markers in pancreatic cancer.Methods The prostate stem cell antigen (PSCA) gene was identified as a marker highly expressed in pancreatic adenocarcinoma and not normal pancreas. RNA from pancreatic and nonpancreatic cancer cell lines as well as tissue and blood from pancreatic cancer and control patients was reverse-transcribed and PSCA quantified by qPCR.Results Individual operator experience affects the results of qPCR, with significantly different copy numbers at experiment numbers 5, 15, and 40. Five of six pancreatic cell lines had PSCA/actin ratios 10-fold greater than nonpancreatic cancer lines. Mean PSCA expression in pancreatic tumor tissue was significantly higher (P < 0.05, Student’s t-test) than in the tissue of benign pancreatic processes. The close correlation of PSCA/actin copy number with number of tumor cells in the blood was demonstrated by regression analysis (r = 0.768, P = 0.0001). PSCA copy number was significantly higher in the blood of patients with metastatic pancreatic cancer than in that of normal patients (P < 0.05, Student’s t-test).Conclusions Such trends suggest that PSCA may prove to be a valuable pancreatic cancer tumor marker. More generally, the technique of qPCR is shown to provide a sensitive method of evaluating markers in cancer patients.This work was presented at the Society of Surgical Oncology Annual Meeting, Los Angeles, CA, March 2003.  相似文献   
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The Calmette-Güerin vaccine (BCG) is administered to all the newborns in Iran in order to prevent tuberculosis. Complications of this vaccine are uncommon. We report disseminated BCG disease in 17 patients less than 10 years old. This is a retrospective study of total of 17 cases who were admitted in Children Medical Center Hospital with systemic syndrome compatible with Mycobacterium disease with evidence of histopathologic demonstration of acid-fast bacilli during 1995-2004. Fourteen cases occurred in children younger than 1 year old. Nine patients were female. Ten of the 17 total cases were associated with an immune deficiency including severe combined immunodeficiency, chronic granulomatous disease and cell mediated immune defect. Response to therapy was ineffective and 10 of them (58.8%) died. Disseminated BCG disease is an uncommon but devastating complication of vaccination that should be considered in the appropriate clinical setting. Immune-compromised infants are at greatest risk and they respond poorly to standard therapies.  相似文献   
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Background and study aimsHepatitis C virus (HCV) is considered the most common aetiology of chronic liver disease (CLD) in Egypt. The disease severity ranges from mild illness to cirrhosis and hepatocellular carcinoma. A role for apoptosis in liver damage caused by HCV chronic infection has been suggested. Cytokeratin 18 (CK-18) is the major intermediate filament protein in the liver and is a known caspase substrate in hepatocyte apoptosis. Therefore, we analysed the serum and tissue levels of CK-18 in patients with chronic HCV infection to evaluate its role in hepatocyte apoptosis. We also correlated CK-18 expression with the severity of hepatic pathology.Patients and methodsThis study examined 80 Egyptian patients with liver disease. There were 69 patients with chronic hepatitis C and 11 patients with hepatitis C-induced cirrhotic changes. Fifteen healthy controls were also included in the study. The levels of CK-18 fragment were quantified in paired serum and liver biopsy samples.ResultsThe serum and tissue CK-18 levels were reduced in chronic HCV patients compared to early cirrhosis patients. This result indicates that serum levels of CK-18 and the hepatic expression of CK-18 might play an important role in disease progression. The serum and tissue levels of CK-18 were significantly increased and directly correlated with inflammation severity, stage of fibrosis, and ALT levels in the chronic HCV group and the cirrhotic liver group. There was no significant difference in viral load between patient cohorts.ConclusionThe serum level and the hepatic expression of CK-18 are related to disease activity and are directly correlated with METAVIR scoring. This result suggests that serum CK-18 levels may be useful for monitoring disease activity in chronic HCV and liver cirrhosis patients.  相似文献   
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