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101.
Su J Zhang A Shi Z Ma F Pu P Wang T Zhang J Kang C Zhang Q 《International journal of oncology》2012,40(4):1162-1170
The Wnt/β-catenin signaling pathway is crucial for human organ development and is involved in tumor progression of many cancers. Accumulating evidence suggests that the expression of β-catenin is, in part, regulated by specific microRNAs (miRNAs). The purpose of this study was to determine the expression of a recently identified epithelial to mesenchymal transition (EMT)-associated tumor suppressor microRNA (miR)-200a, in cancer cells. We also aimed to identify specific miR-200a target genes and to investigate the antitumor effects of miR-200a on the Wnt/β-catenin signaling pathway. We employed TOP/FOP flash luciferase assays to identify the effect of miR-200a on the Wnt/β-catenin pathway and we confirmed our observations using fluorescence microscopy. To determine target genes of miR-200a, a 3' untranslated region (3' UTR) luciferase assay was performed. Cell viability, invasion and wound healing assays were carried out for functional analysis after miRNA transfection. We further investigated the role of miR-200a in EMT by Western blot analysis. We found fluctuation in the expression of miR-200a that was accompanied by changes in the expression of members of the Wnt/β-catenin signaling pathway. We also determined that miR-200a can directly interact with the 3' UTR of CTNNB1 (the gene that encodes β-catenin) to suppress Wnt/β-catenin signaling. MiR-200a could also influence the biological activities of SGC790 and U251 cells. Our results demonstrate that miR-200a is a new tumor suppressor that can regulate the activity of the Wnt/β-catenin signaling pathway via two mechanisms. MiR-200a is a candidate target for tumor treatment via its regulation of the Wnt/β-catenin signaling pathway. 相似文献
102.
目的:探讨国际前列腺症状评分的排尿期/储尿期评分比值(international prostatic symptom score-voiding/storage sub-score ratio,IPSS-V/S)在经尿道前列腺汽化电切术(transurethral electrovaporization prostatectomy,TUVP)术后下尿路症状(lower urinary tract symptoms,LUTS)再评估的临床价值。方法:回顾性分析了2015年1月至2016年12月期间234例接受TUVP的良性前列腺增生(benign prostatic hyperplasia,BPH)患者的国际前列腺症状评分(international prostatic symptom score,IPSS)等临床资料。按照IPSS-V/S比值将患者分为A组(IPSS-V/S≤1,80例)和B组(IPSS-V/S>1,154例)。术后6个月再次评估IPSS,储尿期症状评分(international prostatic symptom score-storage,IPSS-S),排尿期症状评分(international prostatic symptom score-voiding,IPSS-V)和生活质量评分(quality of life,QOL)。结果:234例患者术后6个月IPSS和QOL较术前明显降低,差异有统计学意义(t=33.0,P=0.000;t=34.3,P=0.000)。术后6个月B组患者IPSS改善程度明显优于A组[(12.36±3.67)分 vs. (8.20±3.21)分](t=8.96,P=0.000)。其中A组术后6个月IPSS-S明显高于B组[(9.61±2.88)分 vs. (5.55±2.63)分](t=10.8,P=0.000);而2组患者术后6个月时IPSS-V对比无统计学差异(t=1.56,P=0.120)。虽然A组术后6个月的QOL明显改善[(3.59±0.91)分 vs.(5.19±0.55)分](t=14.8,P=0.000),但是基本满意及以上者仅占13.75%,明显低于B组的70.78%。A组术后6个月IPSS-S各症状评分均有一定改善,改善程度从高到低依次为尿急评分、尿频评分和夜尿评分,其中夜尿评分改善率最低,仅为36.3%(29/80),是A组患者IPSS及QOL改善较小的重要原因。结论:相比IPSS,IPSS-V/S更能准确反映TUVP术后疗效,LUTS排尿期症状改善明显优于储尿期症状。对于以夜尿症为主的BPH/LUTS患者,TUVP对患者QOL改善有限,需要引起临床医师重视。 相似文献
103.
104.
Bredemolic acid (3) is a naturally occurring 2β,3α-isomer of maslinic acid (1) that is an allosteric site inhibitor of glycogen phosphorylase (GP). A practical synthesis of 3 was accomplished (18% yield) in five steps starting from the readily available 2β,3β-diol 6a. In a similar fashion, 2β,3α-dihydroxyurs-12-en-28-oic acid (4) was synthesized as a natural 2β,3α-isomer of corosolic acid (2). Compounds 3 and 4 exhibited significant inhibitory activity against rabbit muscle GPa with IC(50) values of 6.25 and 1.1 μM, respectively. 相似文献
105.
Lipotoxicity is closely related to the etiology and complications of type 2 diabetes mellitus. This study investigated the protective effect of an extract from bamboo Phyllostachys edulis against palmitic acid (PA)-induced lipoapoptosis. The lipo-detoxification function of the bamboo extract (BEX) was evaluated using cell culture models. Cell viability was measured by MTT assay and cell apoptosis was monitored by Annexin V staining. Cellular uptake of fluorescent free fatty acid (FFA) analog was measured by flow cytometry. Protein levels of total protein kinase B (Akt) and phosphorylated Akt (p-Akt) were measured by western blotting. The results show that co-incubating BEX with mouse myoblast C2C12 cells had no effect on the cellular uptake of FFA, but dramatically decreased PA-induced cell apoptosis and protected cell viability. A similar antilipotoxicity effect of BEX was observed in other mammalian cells. BEX significantly decreased the protein levels of both Akt and p-Akt in C2C12 cells under normal cell culture conditions but not under lipotoxic conditions, indicating the regulatory effect of BEX on cell signaling pathways and its response to a high FFA environment. This study demonstrated a novel function of bamboo extract in preventing lipotoxicity in mammalian cells, implicating a promising phytotherapeutic approach for lipo-detoxification. 相似文献
106.
目的 探讨β防御素-1(β-defensin-1,HBD-1)和Toll样受体基因多态性与慢性宫颈炎关系.方法 选取四川大学华西第二医院慢性宫颈炎患者150例作为病例组,100例健康个体作为对照组,提取宫颈上皮细胞DNA,聚合酶链反应-限制性内切酶片断长度多态性(PCR-RFLP)法检测单核苷酸多态性(single nucleotide polymorphism,SNP).结果 慢性宫颈炎组HBD-1外显子-44C/G的CG基因型及G等位基因频率均高于对照组(P<0.05);HBD-外显子-52G/A、-20G/A的基因型和等位基因频率两组比较差异无统计学意义(P>0.05);TLR2 Arg753Gln基因多态性在慢性宫颈炎组和对照组的表达差异无统计学意义(P> 0.05);TLR4 Asp299Gly、TLR4 Thr399Ile在研究人群中没有发现多态性表达.结论 HBD-1-44C/G位点可能是中国汉族人群慢性宫颈炎的易感位点,携带C/G基因型、等位基因G过多分布的女性可能是慢性宫颈炎的易感人群,HBD-1-52 G/A、HBD-1-20G/A、TLR2 Arg753 Gln、TLR4 Asp299Gly、TLR4 Thr399Ile基因多态性与慢性宫颈炎无相关性. 相似文献
107.
To explore the functions of very low density lipoprotein receptor (VLDL-R) subtype Ⅱ in lipoprotein metabolism and foam cells formation, the recombinant plasmid with the two subtypes cDNA was constructed respectively, the ldl A7 cell lines were transfected and two cell lines expressing VLDL-R were obtained: one stably expressing the VLDLR with the O-linked sugar region (type Ⅰ VLDLR) and the other without the O-linked sugar region (type Ⅱ VLDLR). In the study on binding of VLDLR to their nuclein labeled natural ligands (VLDL and β-VLDL), it was found that surface binding of^125I-VLDL or ^125I-β-VLDL of ldl-A7 cells transfected with type Ⅰ VLDLR recombinant (ldl-A7-VRI) was more higher than that of ldl-A7 cells transfected with type Ⅱ VLDLR recombinant (ldl-A7 VRⅡ). After being incubated with VLDL for different time, the contents of triglyceride and total cholesterol in cells were mensurated, and the formation of foam cells and accumulation of lipid in cells was observed by oil-red O staining. The results showed that the contents of triglyceride and total cholesterol in IdI-A7-VR Ⅰ were much higher than those in ldl-A7-VR Ⅱ, and IdI-A7-VR Ⅰ could transform into foam cells notably. It was suggested that type Ⅰ VLDLR binds with relative higher affinity to VLDL and β-VLDL, and internalizes much more lipoprotein into cells. As a result, we can conclude that type Ⅰ VLDLR plays a more important role in lipoprotein metabolism and foam cells formation than type Ⅱ VLDLR。 相似文献
108.
肝内Glisson系统由肝内门静脉、肝内肝动脉和肝内肝管组成。观察和测量了其第一级分支,在显微镜下观察了其第二级分支和第三级分支,研究结果为临床应用提供解剖学资料。 相似文献
109.
Raitt MH Connor WE Morris C Kron J Halperin B Chugh SS McClelland J Cook J MacMurdy K Swenson R Connor SL Gerhard G Kraemer DF Oseran D Marchant C Calhoun D Shnider R McAnulty J 《JAMA》2005,293(23):2884-2891
Context Clinical studies of omega-3 polyunsaturated fatty acids (PUFAs) have shown a reduction in sudden cardiac death, suggesting that omega-3 PUFAs may have antiarrhythmic effects. Objective To determine whether omega-3 PUFAs have beneficial antiarrhythmic effects in patients with a history of sustained ventricular tachycardia (VT) or ventricular fibrillation (VF). Design and Setting Randomized, double-blind, placebo-controlled trial performed at 6 US medical centers with enrollment from February 1999 until January 2003. Patients Two hundred patients with an implantable cardioverter defibrillator (ICD) and a recent episode of sustained VT or VF. Intervention Patients were randomly assigned to receive fish oil, 1.8 g/d, 72% omega-3 PUFAs, or placebo and were followed up for a median of 718 days (range, 20-828 days). Main Outcome Measures Time to first episode of ICD treatment for VT/VF, changes in red blood cell concentrations of omega-3 PUFAs, frequency of recurrent VT/VF events, and predetermined subgroup analyses. Results Patients randomized to receive fish oil had an increase in the mean percentage of omega-3 PUFAs in red blood cell membranes from 4.7% to 8.3% (P<.001), with no change observed in patients receiving placebo. At 6, 12, and 24 months, 46% (SE, 5%), 51% (5%), and 65% (5%) of patients randomized to receive fish oil had ICD therapy for VT/VF compared with 36% (5%), 41% (5%), and 59% (5%) for patients randomized to receive placebo (P = .19). In the subset of 133 patients whose qualifying arrhythmia was VT, 61% (SE, 6%), 66% (6%), and 79% (6%) of patients in the fish oil group had VT/VF at 6, 12, and 24 months compared with 37% (6%), 43% (6%), and 65% (6%) of patients in the control group (P = .007). Recurrent VT/VF events were more common in patients randomized to receive fish oil (P<.001). Conclusion Among patients with a recent episode of sustained ventricular arrhythmia and an ICD, fish oil supplementation does not reduce the risk of VT/VF and may be proarrhythmic in some patients. 相似文献
110.
目的 研究人巨细胞病毒、弓形虫感染与输卵管妊娠的相关性。方法 采用酶联免疫吸附测定 (ELISA)方法和聚合酶链反应 (PCR)技术检测输卵管妊娠患者与对照组血清人巨细胞病毒 (HCMV)和弓形虫 (TOXO)抗体以及生殖道HCMV和TOXODNA。结果 病例组血清HCMVIgG抗体阳性检出率为 31 9% ,明显高于对照组15 8% (P <0 0 5 ) ;HCMVIgM抗体、TOXOIgG、IgM抗体检出率均高于对照组 ,在统计学上无明显差异 (P >0 0 5 ) ;病例组宫颈、宫腔及输卵管组织中均分离到HCMVDNA和TOXODNA ,且宫颈HCMVDNA阳性检出率为14 3% ,明显高于对照组 (P <0 0 5 )。结论 输卵管妊娠与HCMV感染有关 ,TOXO感染为输卵管妊娠的可疑因素。 相似文献