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51.
Draper N Bui M Boulware DC Lloyd M Chiappori AA Pledger WJ Coppola D 《Human pathology》2008,39(12):1784-1791
Gastrointestinal stromal tumors, the most common mesenchymal tumors of the gastrointestinal tract, are characterized by strong expression of c-Kit protein. Recently, it has been shown that gastrointestinal stromal tumors may also contain alterations of genes involved in the regulation of cell cycle. In this study, we evaluate the prevalence and clinical significance of cyclin D1 and D3, Ki-67, p27, and retinoblastoma protein expression in a group of 50 human gastrointestinal stromal tumors selected from the files of the Moffitt Cancer Center. Tissue sections from each case were subjected to immunostaining using the avidin-biotin complex method. Cyclin D1 nuclear positivity was detected in 21 of 50 (42%) and cyclin D3 in 24 of 50 (48%) cases. p27 high immunoreactivity and negative or decreased retinoblastoma protein expression were identified in 33 of 50 (66%) gastrointestinal stromal tumors. In 19 of 50 (38%) tumors, Ki-67 had high labeling index. Direct correlation was observed between cyclin D3 and p27 expression (P < .0001), and between cyclin D1 and retinoblastoma protein (P = .03). Coexpression of cyclin D3 and p27 was demonstrated by immunofluorescence. The p27 protein expression inversely correlated with tumor size (P = .004), but was not correlated with tumor grade (P = .12). Ki-67 directly correlated with both tumor size (P = .03) and tumor grade (P = .008). We report a direct correlation between cyclin D3 and p27 expression in gastrointestinal stromal tumors. Additional alterations in cyclin D1, Ki-67, and retinoblastoma protein expression indicate a disregulated cell cycle in these tumors. 相似文献
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Thiazolidinedione treatment normalizes insulin resistance and ischemic injury in the zucker Fatty rat heart 总被引:13,自引:0,他引:13
Obesity is associated with risk factors for cardiovascular disease, including insulin resistance, and can lead to cardiac hypertrophy and congestive heart failure. Here, we used the insulin-sensitizing agent rosiglitazone to investigate the cellular mechanisms linking insulin resistance in the obese Zucker rat heart with increased susceptibility to ischemic injury. Rats were treated for 7 or 14 days with 3 mg/kg per os rosiglitazone. Hearts were isolated and perfused before and during insulin stimulation or during 32 min low-flow ischemia at 0.3 ml small middle dot min(-1) small middle dot grams wet wt(-1) and reperfusion. D[2-(3)H]glucose was used as a tracer of glucose uptake, and phosphorus-31 nuclear magnetic resonance spectroscopy was used to follow energetics during ischemia. At 12 months of age, obese rat hearts were insulin resistant with decreased GLUT4 protein expression. During ischemia, glucose uptake was lower and depletion of ATP was greater in obese rat hearts, thereby significantly impairing recovery of contractile function during reperfusion. Rosiglitazone treatment normalized the insulin resistance and restored GLUT4 protein levels in obese rat hearts. Glucose uptake during ischemia was also normalized by rosiglitazone treatment, thereby preventing the greater loss of ATP and restoring recovery of contractile function to that of lean rat hearts. We conclude that rosiglitazone treatment, by normalizing glucose uptake, protected obese rat hearts from ischemic injury. 相似文献
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Li S Stanley JR Draper ML Mirabile CP Coleman FH Mulvihill JJ 《The Journal of the Oklahoma State Medical Association》2002,95(4):244-246
The present paper summarizes our first 12 months' experiences of rapid prenatal diagnosis using commercially available diagnostic fluorescence in situ hybridization (FISH) probes for chromosomes X, Y, 13, 18 and 21. The data clearly demonstrate that the advantage of using FISH as an adjunct technique is the fast and reliable determination of the common fetal chromosomal aneuploidies; the results are available in less than 24 hours instead of the 7-14 days with standard techniques. 相似文献
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AIM: To compare mortality and respiratory morbidity in preterm infants born at 4 United Kingdom centers during 1994 and 1995. METHOD: Collection of CRIB scores, respiratory parameters and mortality rates from unit databases. RESULTS: Mortality in center A was 27% (actual number of deaths 36/135), in center B was 30% (39/130), in center C was 28% (51/182), in center D was 39% (60/156). The rate of chronic lung disease (36 week definition) in center A was 16%, in center B was 12%, in center C was 13%, in center D was 15%. The predicted number of deaths by CRIB scores in center A was 54 (95% confidence intervals 45-63), in center B was 33 (25-41), in center C was 53 (43-63), in center D was 46 (37-56). CONCLUSION: Center A had a lower than predicted mortality. Center D had a higher than predicted mortality. There is an urgent need for a national neonatal database to allow comparison between center and to identify reasons for variation in outcomes. 相似文献