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The D‐ ‐ phenotype is a genetic variant of the Rh blood group system. It expresses D antigen but lacks C, c, E and e antigens. In D‐ ‐ phenotype, the RHCE coding region is extensively modified by RHD sequence replacement, nucleotide deletion or splice‐site changes. This article reports the identification of a new D‐ ‐ haplotype in a Comorian man. It exhibits a hybrid gene in which RHCE gene exons 3–8 have been replaced by RHD sequences on the RHCE * C allele background. This allele is associated with no expression of c/C and e/E antigens and overexpression of RhD antigen.  相似文献   
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Here, we show that overexpression of fer tyrosine kinase (FER), a non-receptor tyrosine kinase, predicts poor postoperative outcome and might be involved in cancer-cell survival in non-small cell lung cancer (NSCLC). Systematic screening using in silico analyses and quantitative RT-PCR revealed that FER was overexpressed in about 10% of NSCLC patients. Evaluation of FER expression using immunohistochemistry (IHC) on tissue microarrays was consistent with the mRNA level detected using quantitative RT-PCR. In analyses of 135 NSCLC patients who had undergone potential curative resection, we found that FER overexpression detected using IHC had no association with clinicopathological features such as age, sex, smoking history, histological type, disease stage, T factor, N factor, adjuvant chemotherapy history, or EGFR mutation, but was correlated with poor postoperative survival periods. A multivariate Cox regression analysis showed that this prognostic impact was independent of other clinicopathological features. In functional analyses of FER in vitro, FER exhibited a transforming activity, suggesting that it possesses oncogenic functions. We also found that human lung cancer NCI-H661 cells, which exhibited FER-outlier expression, were led to apoptosis by the knockdown of FER using RNA interference. FER overexpression might serve as a prognostic biomarker and be involved in cancer-cell survival in NSCLC.  相似文献   
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In this study, we examined the effects of overexpression of SIRT1 on IL‐1β‐induced gene expression changes in human chondrocytes to explore a protective role of SIRT1 in human chondrocytes. SIRT1 was overexpressed in human chondrocytes by expression plasmid under stimulation with IL‐1β. SIRT1 was also inhibited by siRNA under stimulation with IL‐1β. Gene expression changes were examined by real‐time PCR. The interaction of SIRT1 and p65 (NF‐κB) were examined by Western blotting. SIRT1, MMP‐13, and ADAMTS‐5 expressions in human cartilage were examined by immunohistochemistry. IL‐1β stimulation significantly up‐regulated MMP‐1, 2, 9, and 13 and ADAMTS‐5. Overexpression of SIRT1 significantly inhibited the up‐regulation of those genes caused by IL‐1β while the inhibition of SIRT1 further increased them. In addition, the overexpression of SIRT1 markedly reduced the IL‐1β‐induced acetylation of p65. SIRT1 expression was clearly detected in the non‐OA cartilage while MMP‐13 and ADAMTS‐5 were undetectable. In contrast, in the OA cartilage, SIRT1 expression was decreased while MMP‐13 and ADAMTS‐5 were increased. Our observations suggested that SIRT1 can play a protective role by suppressing IL‐1β‐induced expressions of cartilage‐degrading enzymes partially through the modulation of the NF‐κB pathway. SIRT1 overexpression might be a new therapeutic approach for OA. © 2012 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 31: 531–537, 2013  相似文献   
15.
Interleukin (IL)-12p40, a subunit of IL-12p70 and IL-23, has previously been shown to inhibit IL-12p70 activity and interferon-gamma (IFN-gamma) production. However, recent evidence has suggested that the role of IL-12p40 is more complex. To study the contribution of IL-12p40 to immune responses against mycobacterial infections, we have used transgenic (tg) mice overexpressing IL-12p40 under the control of a major histocompatibility complex-II promoter. The IL-12p40 transgene was expressed during steady state at concentrations of 129 +/- 25 ng/ml of serum and 75 +/- 13 ng per spleen, while endogenous IL-12p40 was hardly detectable in control littermates. Bacille Calmette-Guérin (BCG) infection strongly induced the expression of IL-12p40 transgene in infected organs, and IL-12p40 monomeric and dimeric forms were identified in spleen of IL-12p40 tg mice. Excessive production of IL-12p40 resulted in a 14-fold increase in IL-12p70 serum levels in tg mice versus non-transgenic mice. IL-23 was also strongly elevated in the serum and spleens of IL-12p40 tg mice through BCG infection. While IFN-gamma and tumour necrosis factor protein levels were similar in IL-12p40 tg and non-transgenic mice, Th2 type immune responses were reduced in IL-12p40 tg mice. The number of BCG granulomas and macrophage expressing inducible nitric oxide synthase were similar in IL-12p40 tg and non-transgenic mice. IL-12p40 tg mice were as resistant as non-transgenic mice to BCG and Mycobacterium tuberculosis infections as they could efficiently control bacillary growth. These data show that high amounts of IL-12p40 promotes IL-12p70 and IL-23 formation, but that does not affect T helper 1 type immune responses and granuloma function, thus leading to normal mycobacterial clearance in infected organs.  相似文献   
16.
目的研究BeclinJ基因对U87胶质瘤细胞自噬和增殖的影响。方法实验分5组:空白对照组.pSUPER—Bec组(表达BeclinsiRNA)与其阴性对照组(pSUPER—non组),pcDNA3.1-Bec组(表达BeclinJ基因质粒)与其阴性对照组(pcDNA3.1-non组)。分别转染U87细胞,采用免疫印迹检测Beclin1、LC3和p62蛋白在各组的表达;用氚标胸腺嘧啶脱氧核苷(3H-TdR)检测各组细胞增殖率。结果转染后48h,pSUPER—Bec组Beclin1、LC3B—11蛋白表达下降,p62蛋白表达升高。pcDNA3.1-Bec组Beclin1、LC3B-Ⅱ蛋白表达升高,p62蛋白表达下降。与空白对照组或pcDNA3.1-non组相比.pcDNA3.1-Bec组细胞增殖速度降低(P〈0.05),其他各组细胞增殖速度无明显差异。结论恶性胶质瘤细胞中自噬相关基因Beclinj表达下降,过表达Beclinl蛋白能增强细胞的自噬活性,抑制细胞的增殖活性。  相似文献   
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BACKGROUND: The role of AT1 receptors in myocardial ischemia/reperfusion injury is unclear. We, therefore, investigated the effects of the AT1 receptor antagonist irbesartan (Irb) in isolated hearts of selective myocardial AT1 overexpressing transgenic [transgenic(alphaMHC-hAT1)594-17] and Sprague-Dawley rats (SD) subjected to ischemia/reperfusion injury. METHODS AND RESULTS: Hearts of 4-week-old male SD or transgenic rats were isolated and perfused with Krebs-Henseleit buffer with or without 10 microM Irb in Langendorff mode. After 15 min of stabilization, pressure-volume curves were obtained and the hearts subjected to 20 min ischemia followed by 30 min reperfusion. A second set of pressure-volume curves was obtained thereafter. Left ventricular developed pressure (LVDP), end-diastolic pressure (LVEDP), total coronary flow (CF) and oxygen consumption (MVO2) were recorded continuously. Myocardial efficiency was derived from the slope of relations of MVO2 to pressure/volume area. After 20 min ischemia, LVEDP was significantly higher in transgenic than in SD (35.7+/-1.8 vs. 29.2+/-1.0 mmHg, P<0.05) or Irb treated transgenic hearts (24.3+/-1.6 mmHg, P<0.05). Myocardial efficiency was increased by Irb before ischemia. Ischemia increased efficiency in SD but not in transgenic rats, Irb increased efficiency in transgenic hearts post-ischemia. CONCLUSION: Transgenic hearts developed ischemic contracture more rapidly than SD hearts as indicated by higher LVEDP during ischemia. This response was antagonized by Irb, indicating a role of AT1 receptors in ischemic contracture, AT1-receptors also appear to be involved in the control of myocardial efficiency.  相似文献   
19.
microRNAs(miRNAs) play an important regulatory role in the self-renewal and differentiation of stem cells. In this study, we examined the effects of miRNA-124(miR-124) overexpression in bone marrow-derived mesenchymal stem cells. In particular, we focused on the effect of overexpression on the differentiation of bone marrow-derived mesenchymal stem cells into neurons. First, we used GeneChip technology to analyze the expression of miRNAs in bone marrow-derived mesenchymal stem cells, neural stem cells and neurons. miR-124 expression was substantially reduced in bone marrow-derived mesenchymal stem cells compared with the other cell types. We constructed a lentiviral vector overexpressing miR-124 and transfected it into bone marrow-derived mesenchymal stem cells. Intracellular expression levels of the neuronal early markers β-III tubulin and microtubule-associated protein-2 were significantly increased, and apoptosis induced by oxygen and glucose deprivation was reduced in transfected cells. After miR-124-transfected bone marrow-derived mesenchymal stem cells were transplanted into the injured rat spinal cord, a large number of cells positive for the neuronal marker neurofilament-200 were observed in the transplanted region. The Basso-Beattie-Bresnahan locomotion scores showed that the motor function of the hind limb of rats with spinal cord injury was substantially improved. These results suggest that miR-124 plays an important role in the differentiation of bone marrow-derived mesenchymal stem cells into neurons. Our findings should facilitate the development of novel strategies for enhancing the therapeutic efficacy of bone marrow-derived mesenchymal stem cell transplantation for spinal cord injury.  相似文献   
20.
Rhabdomyosarcoma (RMS) is one of the most common soft-tissue sarcomas in children and adolescents with poor prognosis. Yet, there is lack of effective prognostic biomarkers for RMS. The present study, therefore, aimed to explore potential biomarkers for RMS based on our previous findings using array comparative genomic hybridization. We investigated guanine nucleotide exchange factor, GEFT, at expression level in 45 RMS patients and 36 normal striated muscle controls using immunohistochemistry using tissue microarrays. The expression rate of GEFT in RMS samples (42/45, 93.33%) was significantly higher (P<0.05) than that in normal controls (5/36, 13.89%). Moreover, the overexpression rate of GEFT in RMS (31/45, 68.89%) was also significantly higher (P<0.05) than that in normal controls (0/36, 0.00%). Increased expression of GEFT correlated significantly with advanced disease stages (stages III/IV) (P=0.001), lymph node metastasis (P=0.019), and distant metastasis (P=0.004), respectively, in RMS patients. In addition, RMS patients having overexpressed GEFT experienced worse overall survival (OS) than those having low levels of GEFT (P=0.001). GEFT overexpression was determined to be an independent prognostic factor for poor OS in RMS patients (hazard ratio: 3.491, 95% confidence interval: 1.121-10.871, P=0.004). In conclusion, these observations provide the first evidence of GEFT overexpression in RMS and its correlations with disease aggressiveness and metastasis. These findings suggest that GEFT may serve as a promising biomarker predicting poor prognosis in RMS patients, thus implying its potential as a therapeutic target.  相似文献   
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