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911.
AIM To study whether C1q/tumor necrosis factor (TNF)-related protein 3 (CTRP3)protect vascular endothelium in rats with hyperuricemia and its potential mechanisms. METHODS An animal model of hyperuricemia was established by using male SD rats drinking 10% fructose water (n=10). The rats drinking normal water served as normal controls (n=10). After 12 weeks, the rats were given a single injection with Ad-CTRP3 or Ad-GFP. The experiment was ended at 14th day after transfection.The serum levels of uric acid and nitric oxide (NO) were evaluated. The serum contents of TNF-α and interleukin-6 (IL-6) were measured by ELISA. HE staining and TUNEL assay were used to assess the morphological changes of intima and apoptosis of endothelial cells in thoracic aorta, respectively. The mRNA levels of endothelial nitric oxide synthase (eNOS), TNF-α and IL-6 were detected by RT-qPCR. The protein levels of CTRP3 and Toll-like receptor 4 (TLR4) were determined by Western blot. RESULTS Compared with normal control group, the rats with hyperuricemia showed lower CTRP3 and higher TLR4 protein levels in the thoracic aorta (P<0.05). Hyperuricemic rats had higher serum contents of uric acid, TNF-α and IL-6 (P<0.05). Also, the intima structure disturbance of thoracic aorta, increased apoptotic rate, higher mRNA levels of TNF-α and IL-6 as well as lower mRNA levels of eNOS were observed (P<0.05). By contrast, CTRP3 over-expression decreased TLR4 protein levels, reduced inflammatory cytokines, and obviously improved the morphology and function of thoracic aorta in the rats with hyperuricemia. CONCLUSION CTRP3 protect vascular endothelium in rats with hyperuricemia maybe via down-regulation of TLR4- mediated inflammatory signaling pathway.  相似文献   
912.
AIM To investigate the activation of related repair pathways after bupivacaine-induced neuronal DNA damage by cDNA gene screening. METHODS The bupivacaine-induced SH-SY5Y neuronal damage and DNA damage model was established. The technique of cDNA microplate array was used to screen the 21 important regulatory factors in the DNA damage repair pathway. Post-analysis of these differentially expressed repair genes for the repair pathway enrichment and distribution was performed. The data were analyzed by GraphPad Prism 6 statistical software to compare differences between groups. RESULTS The viability of SH-SY5Y cells treated with bupivacaine at different concentrations (detected by CCK-8 assay) showed that the IC50 value of bupivacaine was 1.5 mmol/L. The comet assay related index (the comet tail) was increased (P<0.05), the phosphorylation level of γH2AX protein was increased (P<0.05), indicating that DNA damage in the SH-SY5Y cells was significantly aggravated after bupivacaine treatment. The results of cDNA microplate assay showed that compared withcontrol group, the differentially expressed genes after bupivacaine treatment were DNA-PKcs, PTEN, NTH1, RAD9, CSB, GADD45, XPD, XPC-HR23B and P53. The analysis showed that these repair genes were mainly concentrated in the following 3 repair mechanisms: base excision repair, nucleotide excision repair, and non-homologous reconstitution. CONCLUSION The repair genes differentially expressed after neuronal DNA damage caused by local anesthetics are mainly concentrated in the pathways of non-homologous end-joining, base excision repair and nucleotide excision repair.  相似文献   
913.
AIM: To evaluate the association between apolipoprotein E(apoE) gene polymorphism and sporadic Alzheimer's disease (AD). METHOD: A case-control study was undertaken detecting the polymorphism of apoE by polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP).RESULTS:(1)The frequencies of 3/4 genotype and 4 al ele in AD were significant ly higher than that in age-matched controls(P<0.05).(2)The frequency of G/G genotype for apoE IE1 in AD was significantly higher than that in age-mat ched control(P<0.05).(3)The apoE 4 al ele was associated with a tripling of the risk for AD compared with no 4 allele(odd ratio 2.932, 95%CI 1.379~6.226);Homozygosity of the G allele in IE1 was associated with adoubling of the risk for AD compared with the G/C and C/C genotypes(odd rat io 2.223, 95%CI 1.075~4.599).However, the IE1 G al ele is also closely associated with apoE 4.When the sample was split on the basis of apo Egenotype, the associat ion between IE1 G/G genotype and AD was no longer statistically significant.CONCLUSION: ApoE ε4 was a risk factor of AD, and the apparent association between IE1 G/G and AD is a consequence of the association between the ε4 and IE1 G/G genotype.  相似文献   
914.
AIM To study the effect of dihydroartemisinin (DHA) on the radiotherapy efficiency in hepatocellular carcinoma H22 cell tumor-bearing mice and the role of phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT) signaling pathway in this process. METHODS A model of H22 cell tumor-bearing mice was established. The mice was divided into model group, single radiotherapy group, 5-fluorouracil (5-FU) group, and low-, medium- and high-dose DHA groups. The body weight and tumor volume in each group were measured every other day. At the end of administration, blood was collected from the tail of the mice and the animals were killed by neck removal immediately. The synergistic effect of DHA on radiotherapy was determined, and tumor growth inhibitory rate was calculated. The degree of lymphocyte transformation and natural killer (NK) cell activity were measured by MTT, the serum levels of interleukin-2 (IL-2) and IL-4 were measured by ELISA, and the protein levels of PI3K, AKT and p-AKT were determined by Western blot. RESULTS The H22 cell tumor-bearing mouse model was successfully constructed. Compared with model group, the TGT3 (tumor growth time to reach 3 times of volume) of single radiotherapy group was remarkably increased (P<0.05), while tumor weight, lymphocyte transformation degree, NK cell activity, IL-2 and IL-4 levels, PI3K protein level and AKT phosphorylation level were remarkably decreased (P<0.05). Compared with single radiotherapy group, TGT3, EF (enhancement factor), tumor inhibitory rate, lymphocyte transformation degree, NK cell activity, IL-2 level and IL-4 level were increased with the increase in DHA dose (P<0.05), and the PI3K protein level and AKT phosphorylation level were decreased (P<0.05). CONCLUSION DHA may enhance the immunity of tumor-bearing mice by inhibiting the activity of PI3K/AKT signaling pathway, thereby enhancing the efficacy of radiotherapy.  相似文献   
915.
以紫甘蓝品种‘紫辉甘蓝’为试材,在南方塑料大棚内密闭式光照植物培养架中,采用新型LED光源研究了不同光质对紫甘蓝幼苗生长的影响,试验共设置6个处理:R(红)、B(蓝)、8R2B(红光∶蓝光=8∶2)、5R5B(红光∶蓝光=5∶5)、2R8B(红光∶蓝光=2∶8)和荧光灯(对照CK)。结果表明:(1)在8R2B处理下,紫甘蓝幼苗地下部鲜重、地上部鲜重、单株鲜重、株高、根体积、根总表面积和根投影面积均最大;(2)与CK相比,不同光质处理均提高了幼苗叶片叶绿素a、叶绿素b和类胡萝卜素的含量,以2R8B处理最高;(3)与CK相比,除R处理的幼苗可溶性蛋白质含量降低外,其它处理均有助于幼苗可溶性蛋白质含量的积累,以8R2B处理最高;(4)可溶性糖含量以R处理最高;(5)与CK相比,各光质处理均显著降低了幼苗MDA含量,以B处理效果最显著,8R2B和5R5B次之;(6)各光质处理对紫甘蓝幼苗叶片脯氨酸含量的影响与CK相比无显著性差异。  相似文献   
916.
海南岛甘什岭热带低地雨林植物组成与地理成分   总被引:1,自引:0,他引:1  
为揭示海南岛甘什岭热带低地雨林区域植物群落特征、性质和规律,以期为进一步分析生物多样性保育与恢复策略及生态服务功能评估等提供科学依据,在海南岛南部甘什岭自然保护区选择典型低地雨林建立1 hm~2固定样地,进行立地因子和植被调查,并研究其物种组成与地理成分。结果表明:维管植物隶属于65科150属213种,种子植物63科148属211种,分别占海南岛和全国种子植物总科、属、种的32.66%、19.29%,13.56%、4.69%和7.65%、0.78%~0.81%;优势科明显,单种科36个,寡种科24个,共占总科数的92.31%;属内种的变化范围为1~6,单种属最多,占总数的76.00%;科和属的分布区类型均以泛热带分布为主,热带性质占绝对优势,这不同于尖峰岭山地雨林热带-亚热带过度性明显的特点;根据种-面积曲线研究表明,甘什岭热带低地雨林最小取样面积为范围在3 600~6 400 m~2之间,其上限高于海南岛霸王岭热带山地雨林的4 000 m~2最小面积;相较于山地雨林,其植物种类较丰富,地理成分更复杂。  相似文献   
917.
研究红茶提取物对高尿酸血症小鼠血尿酸的影响。将36只雄性KM小鼠随机分为空白组、模型组、红茶提取物低、中、高剂量组及别嘌呤醇组。空白组和给茶组连续1周分别灌胃生理盐水和红茶提取物,给茶组第7天造模后1 h给茶;模型组在第7天腹腔注射氧嗪酸钾并灌胃酵母膏造模。测定结果显示:与模型组相比,各给茶组血尿酸(UA)水平均降低;与模型组相比,给茶组血尿素氮(BUN)水平均降低,其中、高剂量给茶组BUN水平显著降低(P0.05),高剂量组差异极显著(P0.01);各给茶组血肌酐(Cr)值与模型组相比极显著下降(P0.001)。高剂量组黄嘌呤氧化酶(XOD)活性较模型组显著降低(P0.05),低、中剂量组有一定的抑制作用,但无显著差异。研究表明,红茶提取物对氧嗪酸钾和酵母膏导致的小鼠高尿酸血症有明显的改善作用。  相似文献   
918.
对海南粗榧(Cephalotaxus hainanensis Li.)内生真菌F127发酵液化学组分进行研究。用多种色谱技术对F127代谢产物进行分离纯化,以LC-MS、ESI-MS和超导核磁共振分析鉴定化合物结构,最后采用MTT法测定化合物的抗肿瘤活性。从海南粗榧内生真菌F127的发酵液中分离得到5个单体化合物,分别鉴定为oblongolide T(1)、sorbicillin(2)、邻苯二甲酸二丁酯(3)、phomopsolide B(4)、6,8-二羟基-3-甲基-3,4-二氢异香豆素(5),且化合物1、4、5对肿瘤细胞K562、NB4、HL-60、Hep G-2和Lovo表现出不同抑制活性。化合物4对5株肿瘤细胞均表现出抑制活性,对K562、NB4、HL-60抑制效果显著,IC50值分别为3.35、0.014和0.16μg/m L,对Hep G-2和Lo Vo只有温和抑制作用;化合物1对K562、NB4、HL-60抑制作用良好,IC50值分别为51.82、54.25和29.31μg/m L;化合物5对NB4和Hep G-2则具有一定抑制活性;化合物2和3对测试细胞株未表现出抑制活性。5个化合物均是首次从海南粗榧内生真菌中分离得到,并首次报道了化合物1、4对K562、NB4、HL-60的优良细胞毒活性,为进一步研究海南粗榧内生真菌中的活性天然产物奠定了基础。  相似文献   
919.
张旭  李静  徐静 《热带作物学报》2017,38(5):849-853
植物抗氧化研究对寻找高效率、低毒性天然抗氧化剂具有重要的指导意义。以在海南分布较广的红树林植物海莲进行抗氧化活性研究,以期对海莲开发利用的可能性提供理论依据。采用清除DPPH自由基和清除ABTS自由基对海莲不同部位———根、茎、叶、花的乙酸乙酯提取物进行抗氧化能力评价,采用比色法和福林酚法测定总黄酮和总酚含量。结果显示,海莲茎的提取物在4个部位中抗氧化活性最好,清除二者的IC50分别为(0.234±0.053)mg/m L和(0.196±0.080)mg/m L,海莲中酚类物质含量较大,4个部位中茎的总酚含量最多,含量为13.2 mg。说明海莲各部位均显示出了较好的抗氧化能力,具有较好的开发潜力。  相似文献   
920.
以铁观音茶树叶片为材料,利用逆转录PCR及RACE法,克隆了茶树几丁质酶基因CsChi(GenBank登录号为KR078345).CsChi基因的cDNA全长为1 192 bp,包含972 bp的开放阅读框(ORF),编码323个氨基酸.生物信息学分析结果表明,CsChi蛋白的分子量为34.33 ku;理论等电点pI为8.44;原子组成为C1519H2285N413O464S18,总原子数为4 699;蛋白质结构分析显示该蛋白有6个蛋白的跨膜区域,属于跨膜蛋白;存在于细胞外;没有卷曲螺旋结构存在;CsChi基因编码的蛋白属于糖苷水解酶19家族,含有保守的ChtBD1结构域,与溶菌酶的保守结构域类似,可能兼具几丁质酶活性和溶菌酶活性,qPCR定量分析结果显示在不同干旱胁迫处理下茶树的CsChi基因的表达量,与对照组相比有所增加.推测CsChi基因在茶树干旱等逆境胁迫中起重要作用.  相似文献   
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