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991.
Objective: To construct the eukaryotic expression vector for human TSLC1 gene, and to express TSLC1 in HepG2 cells for investigating its effect on HepG2 cell growth. Methods: Full length of TSLC1 cDNA was amplified from RNA of normal human liver by RT-PCR, and cloned into pCI-neo expression vector. The recombinant plasmid pCI-TSLC1 was identified with restriction enzyme and sequenced, and then was stably transfected into HepG2 cells with lipofectamine 2000. The positive clones were examined by western-blotting and immunofluorescence, cell growth was analyzed with MTT assay. Results: The eukaryotic expression vector pCI-TSLC1 was successfully constructed and the stable cell line highly expressing TSLC1 protein was obtained. The growth of TSLCl-transfected cells was significantly suppressed in vitro. Conclusion: The HepG2 stable cell line could highly express TSLC1 protein, which provided a basis for further exploring the roles of TSLC1 in hepatocellular carcinoma.  相似文献   
992.
Objective To investigate the indications, operation techniques and clinical effects of a modified technique of Indiana pouch. Methods A modified technique of Indiana pouch was performed on 5 patients following radical cystectomy. Results 5 cases showed satisfactory therapeutic effects with of follow-up range of 6 to 30 months. All patients were continent day and night with easy catherization. The number of micturations was 5 to 6 times in the daytime and 1 to 3 times in the nighttime. Cystography of 4 cases showed that pouches were spheroidic and volumes were between 400 to 500 ml. Conclusion The advantages of the modified Indiana pouch are as follows: easy manipulation; low tension and high volume in pouches; no reflux; satisfactory urinary continence and few complications. Therefore, it is worthy of clinical popularization.  相似文献   
993.
Monoclonal gammopathy of undetermined significance (MGUS) is characterized by the presence of a serum monoclonal (M) protein level less than 3 g/dL, less than 10% clonal plasma cells in the bone marrow, and the absence of hypercalcemia, renal insufficiency, anemia, or bone lesions attributable to a clonal plasma cell disorder. Patients may be tested for a monoclonal gammopathy by serum protein electrophoresis, immunofixation, and the free light chain (FLC) assay. The prevalence of MGUS is 3% for persons more than 50 years of age and 5% in those more than 70 years of age. The risk of progression to multiple myeloma or a related disorder is 1% per year. The size and type of M protein, the number of bone marrow plasma cells, and the results of the FLC ratio are independent risk factors for progression. Smoldering multiple myeloma (SMM) is a more advanced premalignant phase than MGUS and is characterized by more than 3 g/dL of serum M protein, more than 10% clonal plasma cells in the bone marrow, or both, with no evidence of end-organ damage.  相似文献   
994.
995.

Purpose

Every year, almost one million individuals are diagnosed with hepatocellular carcinoma (HCC) worldwide and more than 690,000 patients die of it. At present, most therapeutic anti-HCC agents are not effective, which is due to the appearance of chemo-resistance and/or toxic side effects. Therefore, it is imperative to find novel more effective anti-HCC agents. Here, we evaluated the effect of giganteaside D (GD), an oleanolic acid saponin from P. scabiosaefolia, on the growth and apoptosis of HCC cells.

Methods and results

Using MTT and clonogenic assays, we found that GD exhibited a significant growth inhibitory effect on the HCC-derived cell lines HepG2 and Bel-7402. In addition, we found that GD induced mitochondria-mediated apoptosis in these HCC-derived cells, as indicated by a decreased mitochondrial potential, activation of Caspase-9 and Caspase-3, cleavage of PARP and release of Cytochrome C from the mitochondria. Besides, we found that GD stimulated the generation of reactive oxygen species (ROS) and that blockage of ROS attenuated the GD-induced mitochondria-mediated apoptosis. Additionally, we found that GD treatment led to a decrease in phosphorylated Erk (p-Erk) and triggered the generation of p-JNK, both components of the mitogen-activated protein kinase (MAPK) signaling pathway. Inhibition of Erk or JNK by specific inhibitors or siRNAs augmented or attenuated the cytotoxic and apoptotic effects of GD.

Conclusions

From our results we conclude that GD can induce ROS-mediated apoptosis in HCC-derived cells through the MAPK pathway. This observation may open up avenues to explore the future use of GD as a HCC chemotherapeutic agent.
  相似文献   
996.
Hepatocellular carcinoma (HCC) is a common malignant tumor worldwide. The prognosis and treatment of this disease have changed little in recent decades because the mechanisms underlying most events of this disease remain obscure. Allelic variation of gene expression is associated with many important biological processes, which provide a new perspective to understand HCC pathogenesis at the molecular level. To identify allelic expression imbalance (AEI) genes in HCCs, we developed a computational method that considered accurate mapping and vigorous AEI detection using paired DNA-seq and RNA-seq data. We analyzed the DNA-seq and RNA-seq data derived from two HCC samples and two cell lines. By applying a strict criterion, a total of 203 tumor-specific AEI genes were identified with high confidence, and several genes have been reported to be associated with the migration or proliferation of cancer cells, such as the genes RELN and DHRS3. In addition, we also found some novel AEI genes in HCCs, such as HNRNPR and PTAFR. Our study provides new insight into AEI events that may contribute to understanding gene expression regulation, cell proliferation and migration, and tumorigenesis.  相似文献   
997.
A disintegrin and metalloproteinase (ADAM) family members are known to process the target membrane-bound molecules through the quick induction of their protease activities under interaction with other molecules, which have diverse roles in tissue morphogenesis and pathophysiological remodeling. Among these, ADAM17 is a membrane-bound protease that sheds the extracellular domain of various receptors or its ligands from the cell membrane and subsequently activates downstream signaling transduction pathways. Importantly, breast cancer remains a mainspring of cancer-induced death in women, and numerous regulatory pathways have been implicated in the formation of breast cancer. Substantial evidence has demonstrated that an obvious increased in ADAM17 cell surface expression has been discovered in breast cancer and was shown to be associated with mammary tumorigenesis, invasiveness, and drug resistance. Over the last decades, it has received more than its share of attention that ADAM17 plays a potential role in breast cancer, including cell proliferation, invasion, angiogenesis, apoptosis, and trastuzumab resistance. In our review, we discuss the mechanisms through which ADAM17 acts on breast cancer tumorigenesis and progression. Thus, this will provide further impetus for exploiting ADAM17 as a new target for breast cancer treatment.  相似文献   
998.
In this study, the mechanical properties of two classes of robocast glass scaffolds are obtained through Computed micro-Tomography (micro-CT) based Finite Element Modeling (FEM) with the specific purpose to explicitly account for the geometrical defects introduced during manufacturing. Both classes demonstrate a fiber distribution along two perpendicular directions on parallel layers with a 90 tilting between two adjacent layers. The crack pattern identified upon compression loading is consistent with that found in experimental studies available in literature. The finite element models have demonstrated that the effect of imperfections on elastic and strength properties may be substantial, depending on the specific type of defect identified in the scaffolds. In particular, micro-porosity, fiber length interruption and fiber detaching were found as key factors. The micro-pores act as stress concentrators promoting fracture initiation and propagation, while fiber detachment reduces the scaffold properties substantially along the direction perpendicular to the fiber plane.  相似文献   
999.
Two couples of dicationic ionic liquids, featuring pyrrolidinium and piperidinium cations and different linker chains, were prepared and characterized. 1,1′-(propane-1,3-diyl)bis(1-methylpyrrolidinium) bromide, 1,1′-(octane-1,8-diyl)bis(1-methylpyrrolidinium) bromide, 1,1′-(propane-1,3-diyl)bis(1-methylpiperidinium) bromide, and 1,1′-(octane-1,8-diyl)bis(1-methylpiperidinium) bromide were synthesized in quantitative yields and high purity and thermally characterized through TGA and DSC analysis. In this study, we propose a preliminary comparative evaluation of the effect of the linker chain length and of the size of the aliphatic ammonium ring on the thermal and solubility properties of bromide dicationic ionic liquids.  相似文献   
1000.
BackgroundThe itAlian pRospective Study on CANGrELOr (ARCANGELO) was aimed to assess the safety of using cangrelor during percutaneous coronary intervention (PCI) in patients with acute coronary syndromes (ACS) in the daily practice.HypothesisThe safety of cangrelor after the transition to oral P2Y12 inhibitors was evaluated as the incidence of bleeding outcomes in the 30 days following PCI according to postauthorization safety study guidelines.MethodsAdults with ACS who were treated with cangrelor in one of the 28 centers involved in the study. Patients who consented to participate were followed in the 30 days following their PCI. Bleedings (Bleeding Academic Research Consortium [BARC] classification), major adverse cardiac events (MACEs), and adverse events were recorded. The interim results at two‐thirds of the enrollment period are presented.ResultsA total of 17 bleedings were observed in the 320 patients who completed the study at this stage. All bleedings were classified as BARC Type 1–2, except for one case of Type 3a (vessel puncture site hematoma). Four patients experienced MACEs (2 acute myocardial infarctions, 1 sudden cardiac death, 1 noncardiovascular death due to respiratory distress, and multiorgan failure). None of the bleedings was rated as related to cangrelor.ConclusionsThe interim results of the ARCANGELO study provide a preliminary confirmation that the use of cangrelor on patients with ACS undergoing PCI is not associated with severe bleedings.  相似文献   
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