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991.
Uncontrolled cell proliferation is one of the hallmarks of cancer and the transition from the G1 to S phase is the most commonly reported cell cycle abnormality in tumors. It has been shown that the oncogenic activity of G1 cyclin E (CCNE) can be amplified by generating hyperactive low molecular weight forms (LMW) through elastase-mediated proteolytic processing. Neutrophil elastase (NE) and proteinase 3 (PR3) are 2 proteases that are aberrantly expressed in breast cancer cells and seem to be involved in cell proliferation. In this study, we evaluated the effect of the expression of these 2 proteases in addition to 2 potential intracellular targets of NE (CCNE1 and CCNE2) on clinical outcome in a population of 205 primary breast cancer patients. By univariate analysis, CCNE1, CCNE2, estrogen receptor and grade significantly predicted relapse free interval (RFI). NE and PR3 did not achieve statistical significance. In a multivariate analysis, elevated CCNE2 [hazard ratio (HR) 2.10, p = 0.008] predicted shorter RFI. In subgroup analyses of the tamoxifen-only treated patients, high CCNE1 levels predicted treatment resistance, while high levels of CCNE2 were associated with poor RFI in untreated patients. Investigation of the relationship between CCNE1, CCNE2 and NE did not show any impact on RFI. To conclude, this study was the first to evaluate these markers at the mRNA level by RT-PCR in a series of primary breast cancer patients, and our results confirmed the impact of high CCNE levels on clinical outcome in systemically untreated and of CCNE1 in tamoxifen-only treated early breast cancer patients.  相似文献   
992.
不同频率电针对大鼠杏仁核内生长抑素mRNA表达的影响   总被引:3,自引:0,他引:3  
赵健  熊克仁  李怀斌 《针刺研究》2006,31(2):103-106
目的:观察不同频率电针大鼠“足三里”穴对杏仁核内生长抑素(SOM)mRNA表达的影响。方法:雄性SD大鼠30只,随机分为对照组2、Hz电针组和128 Hz电针组,每组10只。采用原位分子杂交方法,观察不同频率电针大鼠一侧“足三里”穴30 min后,大鼠杏仁核内SOM mRNA的表达。结果:电针对大鼠杏仁核内SOM mRNA的表达有上调作用,并且高频电针作用强于低频电针。电针后杏仁核各亚细胞群内SOM mRNA阳性神经元的数量增加以中、小型细胞较为明显;在细胞染色程度上以中等程度染色和淡染细胞的数量增加为主,细胞平均灰度值有所增加。结论:不同频率电针对大鼠杏仁核内SOM mRNA的表达有明显影响。  相似文献   
993.
OBJECTIVE: To compare DNA-based and mRNA-based methods for detection of high-grade cervical neoplasia in Norway. METHODS: HPV prevalence was analyzed in 383 women with positive index cytology, selected from gynecology clinics. All patients were investigated by a new PAP smear, histology, and two commercially available HPV tests: Hybrid Capture II (Digene, Gaithersburg, MD) and the Pre Tect HPV-Proofer (NorChip AS). Cases with positive DNA test and negative mRNA test and cases with high-grade histology and negative HPV tests were retested with PCR and sequencing. We regarded the infection as latent or transient if sequencing revealed an HPV type included in both assays. RESULTS: High-risk HPV was detected in 99.7% of the histological confirmed high-grade lesions (CIN2+) (290/291). The DNA test was positive in 95% (275/291), and the mRNA test was positive in 77% (225/291) of the histological confirmed high-grade lesions. All invasive carcinomas were mRNA positive. The DNA test was significantly more often positive in benign and low-grade lesions, some of which were found to be false positive due to cross-contamination with unrelated types. High-grade histology was detected in 83% of women with normal cytology and positive mRNA test. Latent or transient infections were detected in 11 low-grade and 12 high-grade preinvasive lesions. Sequencing revealed high-risk HPV types included only in the DNA test in 35 high-grade preinvasive lesions, HPV 52 and 58 were the most prevalent HPV types. CONCLUSIONS: These HPV tests have the potential to improve the detection rate of high-grade cervical neoplasia, with some limitations. The mRNA test seems to be more appropriate for risk-evaluation. Larger scale, population based studies are necessary to evaluate the predictive values of HPV testing in Norway.  相似文献   
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Changes in crystallin synthesis and crystallin mRNA content were followed in the epithelial and fiber cells of rat lenses during the development and reversal of galactose cataracts. Crystallin synthesis was not lowered in the lens epithelial cells throughout the 18 days of galactose feeding. By contrast, crystallin synthesis appeared partially reduced in the fiber cells of cultured lenses after the rats had been on a diet of 50% galactose for 6 days, and was essentially arrested in the lens fiber cells after the rats were fed galactose chow for 12 or 18 days. In vitro translation tests in a rabbit reticulocyte lysate demonstrated that control lenses contained α-, β- and γ-crystallin mRNAs in the cortical and nuclear fiber cells. The lens fiber cells of the 6-day galactosemic rats still possessed a full complement of crystallin mRNAs but those of the 15-day galactosemic rats had no detectable crystallin mRNAs. After 12 days the galactosemic lenses had lost approximately half of the crystallin mRNAs from the cortical fiber cells and all of the mRNAs from the nuclear fiber cells. Both crystallin synthesis and crystallin mRNA content recovered in the cortical fiber cells, but not in the nuclear fiber cells, during reversal of the galactose cataract. These results indicate that the reduction in crystallin synthesis is confined to the fiber cells and occurs initially by a decreased efficiency of utilization of crystallin mRNAs and subsequently by the degradation of the mRNAs. Previous experiments provide evidence that the impaired utilization of the crystallin mRNAs is due to the alterations in electrolytes in the cataractous lenses.  相似文献   
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Human ABCA8, a new member of the ATP binding cassette (ABC) transporter family, transports certain lipophilic drugs, such as digoxin. To investigate the roles of this transporter, we cloned a mouse homologue of ABCA8, from a mouse heart cDNA library, named ABCA8a. The deduced mouse ABCA8a protein is 66% identical with that of human ABCA8 and possesses features common to the ABC superfamily. It was found that ABCA8a was mainly expressed in the liver and heart, similar to human ABCA8. We further evaluated the effect of acute digoxin (a substrate for ABCA8) intoxication on the mRNA expression of ABCA8 using northern blotting with a 3' non-coding region as a probe to avoid cross-hybridization with other ABCA genes. Following acute digoxin infusion, the mRNA expression of ABCA8 was significantly reduced in the liver 12-24 h after injection (14.7% of vehicle treatment), but not in the heart and kidney. Real-time quantitative polymerase chain reaction analysis confirmed the reduction in ABCA8a mRNA. Similar reductions in ABCA5, ABCA7, ABCA8b and ABCA9 mRNA were also observed. A comparable amount of digitoxin did not affect ABCA8a mRNA expression in the liver. The results suggest that ABCA8 may play a role in digoxin metabolism in the liver.  相似文献   
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