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121.
AIM: To study the role of translationally controlled tumor protein (TCTP) in the proliferation, migration and invasion of phosphatase of regenerating liver-3(PRL-3)-promoted colon cancer cells.METHODS: The vectors pAcGFP-C3 and pAcGFP-C3-PRL-3 were constructed and transfected into the colon cancer cell line LoVo.LoVo-PRL-3 cells stably expressing PRL-3 and LoVo-control cells were established. The expression levels of PRL-3 and TCTP in both cells were detected by Western blotting and real-time PCR. The specific siRNA sequence for TCTP mRNA and control-siRNA were synthesized and transfected into the LoVo-PRL-3 cells. TCTP expression at mRNA and protein levels in LoVo-PRL-3 was detected by Western blotting and real-time PCR 24 h, 48 h and 72 h after transfection. The proliferation, migration and invasion abilities of LoVo-control cells, LoVo-PRL-3 cells, TCTP-siRNA and control-siRNA cells were detected by CCK-8 assay and the method of Transwell cell culture chambers.RESULTS: The expression of TCTP at mRNA and protein levels in LoVo cells was significantly increased after PRL-3 transfection (P<0.05). TCTP mRNA was significantly inhibited 24 h, 48 h and 72 h after transfection of TCTP-siRNA (P<0.01). TCTP protein was also significantly inhibited 48 h and 72 h after transfection (P<0.01). Compared with LoVo-control cells, the proliferation, migration and invasion abilities of LoVo-PRL-3 cells were significantly enhanced (P<0.05). However, lowering the up-regulated expression of TCTP in LoVo-PRL-3 cells inhibited the proliferation, migration and invasion abilities (P<0.05). CONCLUSION: PRL-3 promotes proliferation, migration and invasion of colon cancer cells by up-regulating the TCTP expression. siRNA targeting TCTP may be an effective method for prevention and treatment of colon cancer cell metastasis.  相似文献   
122.
AIM: To observe the immunoregulatory effects of prostaglandin E2 receptor (EP) subtypes EP2/EP4 on the B-cells of collagen-induced arthritic(CIA)mice. METHODS: DBA/1 mice were immunized with chicken type II collagen emulsified in Freunds complete adjuvant to induce arthritis. B-cells were isolated from the splenocyte suspension by positive selection using anti-CD19 monoclonal antibody immunomagnetic beads. The expression of MHC II, CD 80 and CD86 was examined by flow cytometry. The mRNA levels of EPs, interferon γ (IFN-γ), tumor necrosis factor α (TNF-α), IL-6, IL-4, IL-10 and transforming growth factor-β (TGF-β) were detected by real-time RT-PCR. RESULTS: The rank of the mRNA levels of EPs was EP2>EP1>EP3>EP4 in B-cells and EP2/EP4 mRNA expression was obviously increased in CIA mice. EP2 antagonists inhibited the expression of MHC II, CD80 and CD86. EP4 antagonist had little effect on CD80. EP2/EP4 antagonists inhibited the mRNA expression of IFN-γ, TNF-α, and IL-6 (P<0.05 or P<0.01) and increased the expression of IL-10 (P<0.01 or P<0.05). Furthermore, the antagonists of EP2 and EP4 also increased the mRNA expression of IL-4 and TGF-β (P<0.01), respectively. CONCLUSION: PGE2 modulate the pathogenesis of CIA via EP2/EP4 by regulating the expression of surface molecules and cytokines in B-cells. EP2/EP4 may be a new therapeutic target for treating rheumatoid arthritis.  相似文献   
123.
AIM: To investigate the effects of lenalidomide alone or combined with bortezomib on induction of apoptosis in multiple myeloma(MM) KM3 cells.METHODS: The KM3 cells were treated with lenalidomide alone or combined with bortezomib. The number of viable cells was determined by trypan blue exclusion. Apoptotic cells were simultaneously stained with annexin V-FITC and PI and determined by flow cytometry. RT-PCR was used to examine the level of p65 mRNA. Western blotting was used to examine the protein levels of P65, pP65, caspase-3,-8, -9, and poly (ADP-ribose) polymerase (PARP). RESULTS: Lenalidomide-inhibited the cell growth and induced apoptosis of KM3 cells. The mechanism responsible for lenalidomide-mediated inhibition was via NF-κB and activation of caspase-mediated induction of apoptosis. A synergistic effect was observed when combination of lenalidomide with bortezomib was used. CONCLUSION: Lenalidomide inhibits the growth and induces apoptosis in KM3 cells. There is a synergistical effect when combination of lenalidomide with bortezomib is in use.  相似文献   
124.
Chemokines and their receptors have been implicated mostly in tumor progression and metastasis. Atypical chemokine receptors (ACKRs) comprise a group of 7-transmembrane domain proteins structurally similar to G protein-coupled receptors. However, ACKRs do not induce classical signaling via the typical G protein-mediated pathways. ACKRs efficiently internalize the cognate chemokine ligands and act as scavengers instead. ACJRs are composed of at least 3 members of chemokine receptors:Duffy antigen receptor for chemokines (DARC, also known as ACKR1), D6 (also known as ACKR2) and ChemoCentryx chemokine receptor (CCX-CKR, also known as ACKR4). These receptors bind to and/or internalize their chemoattractant ligands without activating signal transduction cascades leading to cell migration. In this review, we summarize the recent progress regarding the roles of ACKRs in the progression and metastasis of tumor.  相似文献   
125.
吉林省不同产地人参中微量元素含量测定   总被引:1,自引:0,他引:1  
张影  李函颖 《北方园艺》2015,(3):135-137
以人参为试材,采用原子吸收光谱法,对吉林省集安市、通化市、临江市、敦化市、蛟河市、桦甸市、抚松县、长白县、靖宇县、汪清县、江源区11个地区采集的生晒参样本进行了微量元素含量测定,其中包括Cr、Mn、Ni、Fe、Zn、Cu、Co和Na元素。结果表明:不同产地之间,除Zn元素外,其余微量元素含量差异均较大。该研究可为人参产地鉴定提供辅助依据。  相似文献   
126.
李位三 《蜜蜂杂志》2011,31(5):20-22
和其他种植、养殖业比较而论,我国蜂业属低碳产业。它是利用蜜蜂群体生命活动的本能,生产天然蜂产品,并为植物授粉增加子实量以及维护了植物多样性,是低能耗、低污染、基本上是零排放的、公益性很强的蜜蜂产业。  相似文献   
127.
基于MSP430F149的便携式温湿度监测仪的设计   总被引:2,自引:0,他引:2  
为了及时、方便地获取植物病害预测预报等所必需的气象数据,作者设计了一种便携式温湿度气象监测仪,并给出了其硬、软件设计方法。该监测仪以超低功耗单片机MSP430F149、智能传感器SHT15和U盘为主要元器件,能实时地进行温度、湿度和叶面湿度的采集、显示和存储。该监测仪具有体积小、重量轻、携带方便、性价比高和数据存储量大等特点,既可单独使用,也可作为下位机嵌入到系统中实现数据采集和处理的功能。  相似文献   
128.
水稻OsRFP1基因的原核表达与蛋白纯化   总被引:1,自引:0,他引:1  
以推导的氨基酸序列分析,水稻OsRFP1基因编码一分子量为34.24kDa锌指蛋白。将OsRFP1基因编码区cDNA序列插入到pGEX4T-3载体中构建OsRFP1-gst融合基因的表达载体,并将质粒转化宿主菌大肠杆菌BL21DE3。经IPTG诱导,融合蛋白在BL21DE3细胞中获得表达。利用亲和层析的方法对融合蛋白进行了纯化,SDS-PAGE蛋白电泳显示获得一60kDa的唯一蛋白条带,即OsRFP1-GST融合蛋白。  相似文献   
129.
丛枝菌根真菌对番茄植株内源激素含量的影响   总被引:3,自引:0,他引:3  
于温室盆栽条件下对番茄(Lycospersicon esukurentamu)幼苗接种丛枝菌根(AM)真菌摩西球囊霉(Glomusmosseae)、地表球囊霉(Glomus versiforme)、根内球囊霉(Glomus intraradices)、幼套球囊霉(Glomus etunicatum)或珠状巨孢囊霉(Gigaspora margarita)10d后定期采样,应用间接酶联免疫吸附分析法(ELISA)测定各处理番茄植株根和叶片内源激素吲哚乙酸(IAA)、赤霉素(GA)、玉米素核苷(ZR)和脱落酸(ABA)含量。接种20d G.mosseae处理的番茄根系菌根侵染率高达68.5%,显著高于其他接种处理;供试AM真菌显著增加了番茄植株鲜重、株高、地上部和地下部干重、其根或叶内IAA、GA、ZR和ABA含量均显著高于不接种对照,以G.mosseae处理的根或叶中IAA、GA、ZR和ABA含量最高。  相似文献   
130.
对《海洋调查规范》中测定海水磷酸盐的常规方法进行了优化 ,达到了简化过程 ,缩短分析时间以适应水下现场自动分析的目标。此外 ,实验还对磷酸盐测定所使用的试剂及标准贮备液的稳定性进行了一系列的研究 ,改进试剂保存方法 ,延长试剂使用寿命 ,以满足长期现场测定的要求  相似文献   
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