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991.
Abstract

Pancreatic cancer is one of the deadliest cancers across the world with an average 5-year survival rate of less than <6%. In this study, gemcitabine (GEM) and HIF1α-siRNA loaded GE-11 peptide conjugated liposome was successfully prepared and evaluated for its antitumor efficacy in pancreatic cancer cells. The GE11 increased the targeting specificity of liposome carrier and increased the intracellular concentrations in the cancer cells. Furthermore, synergistic combination of GEM and HIF1a-siRNA exhibited remarkable improvement in the declining of cancer cell proliferations. siRNA could effectively decrease the expression of HIF1a gene in the cancer cells. Importantly, GE-11 peptide-conjugated GEM/siRNA-loaded liposomes (GE-GML/siRNA) increased the total amount of apoptosis cells with higher proportion of cells in late apoptosis phase. GE-GML induced remarkable apoptosis of cancer cells and induced chromatin condensation and nuclear fragmentation which are considered to be typical features of apoptosis and cell death. GE-GML/siRNA showed a significant reduction in the tumour burden suggesting the superior anticancer efficacy of this formulation. GE-GML/siRNA showed four-fold reduction in tumour compared to control and two-fold reduction compared to GE-GML, respectively. Overall, present work lays foundation for the combination of GEM and HIF1a-siRNA loaded in a targeted nanocarrier system as a unique therapeutic option in pancreatic cancer treatment.  相似文献   
992.
宋俊芳  郭述珍 《护理研究》2012,26(9):820-821
护士门诊作为一种护理工作模式,旨在通过科学化、系统化、专业化的护理指导,使慢性病病人得到专业的护理知识.高血压是导致心脑血管病、肾脏病发生的最重要的危险因素[1],是全球人类最常见的慢性病.高血压病的预后与血压是否控制良好有关[2],而血压控制又与病人的规范用药和良好的生活方式有关.我院门诊部对高血压病病人实施健康教育综合护理取得了较好效果.现报道如下. 1资料与方法 1.1一般资料 2010年1月-2011年1月我院收治的高血压病病人320例,均符合《中国高血压防治指南》2005修订版规定的高血压诊断标准[3].其中男214例,女106例;年龄50岁~81岁(60岁±12岁);病程5年~31年(13.2年±7.9年);Ⅰ级115例,Ⅱ级135例,Ⅲ级70例;合并糖尿病58例;未服用降压药物47例.  相似文献   
993.
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996.
吴介恒  卢兴兵  李荣妍  吕智慧  黄莎圆子  刘梦娜  郭素红 《重庆医学》2012,41(26):2692-2693,2697,2676
目的筛选建立胰腺癌动物模型最适合成瘤的硫唑嘌呤(AZA)浓度。方法将40只SD大鼠按照AZA浓度的不同分为5组:空白对照组(A组)、2.6mg/kg AZA组(B组)、2.2mg/kg AZA组(C组)、1.8mg/kg AZA组(D组)、1.4mg/kgAZA组(E组),每组8只。A组每天灌服2mL生理盐水,B、C、D、E组每天灌服相应浓度的AZA生理盐水液2mL。第30天后进行SD大鼠皮下移植Mia PACAⅡ胰腺癌细胞悬液,通过检测大鼠血浆CA24-2和制作胰腺组织病理切片的方法来判断其是否成瘤。结果接种胰腺癌细胞后的第15、20、25、30天,各造模组大鼠血中的CA24-2水平均有不同程度的升高,其中B组在移植后的第15、20、25、30天,体内CA24-2水平分别为(51.56±2.14)、(51.61±1.21)、(54.66±1.02)、(56.00±0.38)U/mL,与C、D、E组比较,差异有统计学意义(P<0.05),且成瘤率最高,为83.3%。此外,胰腺病理切片镜下显示细胞核畸形、细胞大小不等,可见双核细胞及1~2个核仁,细胞核大且深染等病理特征,同时发现在移植部位的淋巴结和胰腺周围的淋巴结肿大。结论当AZA浓度为2.6mg/kg时,最有利于制作大鼠胰腺癌模型。  相似文献   
997.
The present study was designed to investigate the effects of p-cymene on lipopolysaccharide (LPS)-induced inflammatory cytokine production both in vitro and in vivo. The production of tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), interleukin-6 (IL-6), and interleukin-10 (IL-10) in LPS-stimulated RAW 264.7 cells and C57BL/6 mice was evaluated by sandwich ELISA. Meanwhile, the mRNA levels of cytokine genes were examined in vitro by semiquantitative RT-PCR. In a further study, we analyzed the activation of nuclear factor-κB (NF-κB) and mitogen-activated protein kinase (MAPK) signaling pathways by western blotting. We found that p-cymene significantly regulated TNF-α, IL-1β, and IL-6 production in LPS-stimulated RAW 264.7 cells. Furthermore, the levels of relative mRNAs were also found to be downregulated. In in vivo trail, p-cymene markedly suppressed the production of TNF-α and IL-1β and increased IL-10 secretion. We also found that p-cymene inhibited LPS-induced activation of extracellular signal receptor-activated kinase 1/2, p38, c-Jun N-terminal kinase, and IκBα. These results suggest that p-cymene may have a potential anti-inflammatory action on cytokine production by blocking NF-κB and MAPK signaling pathways.  相似文献   
998.
Asiatic acid is a major pentacyclic triterpene isolated from Centella asiatica. It shows a variety of bioactivities. In order to obtain its derivatives, potentially useful for detailed pharmacological studies, the substrate was subjected to incubations with selected micro-organisms. In this work, asiatic acid was converted into three new compounds: 2α,3β,23,30-tetrahydroxyurs-12-ene-28-oic acid (1), 2α,3β,22β,23-tetrahydroxyurs-12-ene-28-oic acid (2), and 2α,3β,22β,23,30-pentahydroxyurs-12-ene-28-oic acid (3) by the fungus Alternaria longipes AS 3.2875. The structures of the three metabolites were determined by 1D and 2D NMR spectral data.  相似文献   
999.
1000.
BACKGROUND A large proportion of gastric cancer patients are susceptible to chemoresistance, while the underlying mechanism remains obscure. Stress granules (SGs) play a self-defence role for tumour cells in inhibiting chemotherapy-induced apoptosis. As an SG assembly effector, G3BP1 (Ras-GTPase-activating protein SH3 domain-binding protein) has been reported to be overexpressed in gastric cancer; thus, here we aim to explore its potent roles in gastric cancer chemoresistance.METHODS Kaplan–Meier analysis was used to compare survival rates in gastric cancer patients with different G3BP1 expression. The influence of G3BP1 on gastric cancer cell chemoresistance and apoptosis were evaluated by in vitro and in vivo approaches. The interaction between G3BP1 and YWHAZ was assessed by immunohistochemistry, immunoprecipitation and immunofluorescence.RESULTS G3BP1 was associated with the poor outcome of gastric cancer patients who received adjuvant chemotherapy. G3BP1 knockdown significantly increased the sensitivity of gastric cancer cells to chemotherapy drugs. Mechanically, cell apoptosis and pro-apoptotic-associated molecules were significantly elevated upon G3BP1 depletion. Gene co-expression network analyses identified YWHAZ as the critical interlayer of G3BP1; as a result, G3BP1 interacted with YWHAZ to sequester Bax into the cytoplasm. Clinically, G3BP1highYWHAZhigh gastric cancer patients displayed the worst outcome compared with other patients after chemotherapy.CONCLUSIONS The expression of G3BP1 and YWHAZ could predict the adjuvant chemotherapy benefit in gastric cancer patients.Subject terms: Gastric cancer, Cell death  相似文献   
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