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1.
Artemether is the derivative extracted from Chinese traditional herb and originally used for malaria. Artemether also has potential therapeutic effects against tumors. Vascular cell adhesion molecule-1 (VCAM-1) is an important cell surface adhesion molecule associated with malignancy of gliomas. In this work, we investigated the role and mechanism of artemether combined with shRNA interference of VCAM-1 (shRNA-VCAM-1) on the migration, invasion and apoptosis of glioma cells. U87 human glioma cells were treated with artemether at various concentrations and shRNA interfering technology was employed to silence the expression of VCAM-1. Cell viability, migration, invasiveness and apoptosis were assessed with MTT, wound healing, Transwell and Annexin V-FITC/PI staining. The expression of matrix metalloproteinase-2 (MMP-2), matrix metalloproteinase-9 (MMP-9) and phosphorylated Akt (p-Akt) was checked by Western blot assay. Results showed that artemether and shRNA-VCAM-1 not only significantly inhibited the migration, invasiveness and expression of MMP-2/9 and p-Akt, but also promoted the apoptosis of U87 cells. Combined treatment of both displayed the maximum inhibitory effects on the malignant biological behavior of glioma cells. Our work revealed the potential therapeutic effects of artemether and antiVCAM-1 in the treatments of gliomas.  相似文献   
2.
【目的】研究蚯蚓提取物对家蚕Bombyx mori中肠组织氧化应激及抗氧化酶含量的影响,探究蚯蚓提取物的抗氧化功能。【方法】分别给家蚕5龄幼虫饲喂蚯蚓(赤子爱胜蚓Eisenia foetida)提取液原液的50, 100和200倍稀释液处理后的桑叶,测定处理6 d后家蚕中肠组织中氧化损伤产物丙二醛(MDA)和乳酸脱氢酶(LDH)的含量;利用qRT-PCR检测家蚕中肠组织中抗氧化酶关键基因(Cat,Sod和GSH-Px)的mRNA表达水平;同时采用ELISA法检测中肠组织中抗氧化酶[过氧化氢酶(CAT)、超氧化物歧化酶(SOD)和谷胱甘肽过氧化物酶(GSH-Px)]含量及总抗氧化能力(T-AOC)。【结果】与对照组相比,50, 100和200倍稀释组家蚕中肠组织中MDA, CAT, SOD和GSH-Px含量及T-AOC均差异不显著,200倍稀释组LDH含量显著降低了9.85%,100倍稀释组中肠中Cat和GSH-Px的表达量均显著高于对照组,3个稀释组中Sod的表达量均显著高于对照组。【结论】添食蚯蚓提取物可通过降低家蚕中肠LDH含量、提高抗氧化酶基因的表达水平进而提高家蚕的抗氧化能力。  相似文献   
3.
Although oocytes from prepubertal animals are found less competent than oocytes from adults, the underlying mechanisms are poorly understood. Using the mouse oocyte model, this paper has tested the hypothesis that the developmental potential of prepubertal oocytes is compromised due mainly to their impaired potential for glutathione synthesis. Oocytes from prepubertal and adult mice, primed with or without eCG, were matured in vitro and assessed for glutathione synthesis potential, oxidative stress, Ca2+ reserves, fertilization and in vitro development potential. In unprimed mice, abilities for glutathione synthesis, activation, male pronuclear formation, blastocyst formation, cortical granule migration and polyspermic block were all compromised significantly in prepubertal compared to adult oocytes. Cysteamine and cystine supplementation to maturation medium significantly promoted oocyte glutathione synthesis and blastocyst development but difference due to maternal age remained. Whereas reactive oxygen species (ROS) levels increased, Ca2+ storage decreased significantly in prepubertal oocytes. Levels of both catalytic and modifier subunits of the γ-glutamylcysteine ligase were significantly lower in prepubertal than in adult oocytes. Maternal eCG priming improved all the parameters and eliminated the age difference. Together, the results have confirmed our hypothesis by showing that prepubertal oocytes have a decreased ability to synthesize glutathione leading to an impaired potential to reduce ROS and to form male pronuclei and blastocysts. The resulting oxidative stress decreases the intracellular Ca2+ store resulting in impaired activation at fertilization, and damages the microfilament network, which affects cortical granule redistribution leading to polyspermy.  相似文献   
4.

Background and Purpose

Short-term combined use of clopidogrel and aspirin improves cerebrovascular outcomes in patients with symptomatic extracranial or intracranial stenosis. Antiplatelet non-responsiveness is related to recurrent ischemic events, but the culprit genetic variants responsible for the non-responsiveness have not been well studied. We aimed to identify the genetic variants associated with poor clinical outcomes.

Methods

Patients with symptomatic extracranial or intracranial stenosis scheduled for stenting and receiving dual antiplatelets (clopidogrel 75 mg and aspirin 100 mg daily) for at least 5 days before intervention were enrolled. Ischemic events including recurrent transient ischemic attack, stroke, myocardial infarction, and vascular-related mortality within 12 months follow-up were recorded. We examined the influence of genetic polymorphisms on treatment outcome in our patients.

Results

A total of 268 patients were enrolled into our study and ischemic events were observed in 39 patients. For rs662 of paraoxonase 1 (PON1), allele C was associated with an increased risk of ischemic events (OR = 1.64, 95%CI = 1.03–2.62, P = 0.029). The A-allele carriers of rs2046934 of P2Y12 had a significant association with adverse events (OR = 2.01, 95%CI = 1.10–3.67, P = 0.041). The variant T-allele of cyclooxygenase-1 (COX1) rs1330344 significantly increased the risk of recurrent clinical events (OR = 1.85, 95%CI = 1.12–3.03, P = 0.017). The other single nucleotide polymorphism (SNP) had no association with ischemic events.

Conclusions

PON1, P2Y12 and COX1 polymorphisms were associated with poorer vascular outcomes. Testing for these polymorphisms may be valuable in the identification of patients at risk for recurrent ischemic events.  相似文献   
5.
6.
β-六六六对多刺裸腹溞生命表统计学参数的影响   总被引:7,自引:0,他引:7       下载免费PDF全文
应用生命表统计学方法研究了不同浓度(0.001、0.01、0.1、1、10、100和1000μg/L)的β-六六六对多刺裸腹溞(Moina macrocopa)种群统计学参数的影响。结果表明,与对照组相比,浓度为1000μg/L的β-六六六显著降低了多刺裸腹溞出生时的生命期望和净生殖率,100和1000μg/L的β-六六六显著降低了多刺裸腹溞的世代时间,0.1和1μg/L的β-六六六显著提高了多刺裸腹溞的种群内禀增长率。  相似文献   
7.
应用生命表统计学等方法对镜湖萼花臂尾轮虫夏季种群内4个在生化遗传特征上互不相同的克隆(克隆A、B、c和D)在4种温度(15℃、20℃、25℃和30℃)下的生活史特征及其对升高的温度的反应进行了比较研究。结果表明,温度对萼花臂尾轮虫存活率和繁殖率的影响在不同克隆间存在着差异。20℃和25℃下,4个克隆轮虫的世代时间和净生殖率均分别无显著的差异;20℃、25℃和30℃下,4个克隆轮虫的平均寿命和出生时的生命期望亦然。其余各温度下,4个克隆间轮虫的其他生命表参数均有显著的差异。20℃、25℃和30℃下,4个克隆轮虫所产后代中的混交雌体百分率间均具有显著的差异,且克隆c轮虫所产后代中的混交雌体百分率最高。15℃下,克隆D轮虫的个体适合度最高;25℃下,克隆A和B轮虫的个体适合度较高。4个克隆轮虫的生活史特征对升高的温度的反应也存在着差异。忽略温度的影响时,4克隆间,克隆D轮虫的世代时间、平均寿命和出生时的生命期望最短,净生殖率、种群内禀增长率和个体适合度均最低;克隆C轮虫所产后代中的混交雌体百分率最高。30℃下,4个克隆轮虫的种群内禀增长率存在着差异可能是不同基因型的轮虫克隆群在种群内所占的比例不同的重要原因;而它们的个体适合度相似则可能是不同基因型的轮虫克隆群在夏季镜湖中共存的主要原因之一。  相似文献   
8.
通过对萼花臂尾轮虫、角突臂尾轮虫、壶状臂尾轮虫、十指臂尾轮虫、镰形臂尾轮虫、尾突臂尾轮虫和红臂尾轮虫等7种轮虫mtDNA COⅠ序列分析,并以透明囊足轮虫为外群,使用MEGA软件构建臂尾轮属轮虫系统发生树(ME树和NJ树)以探讨臂尾轮属的系统发生和该属中几个种类的分类地位.结果表明本研究所涉及的轮虫mtDNA COⅠ平均序列差异百分比为24%;在两个系统树中,淡水臂尾轮虫和海水臂尾轮虫均独立成枝;用两种方法得到的系统发生树均支持将十指臂尾轮虫作为一个独立的支系分离出来.壶状臂尾轮虫和红臂尾轮虫应属于不同的种;来自芜湖、墨西哥和美国的十指臂尾轮虫以及来自芜湖和澳大利亚的萼花臂尾轮虫应分别互为姐妹种.本研究还首次揭示了角突臂尾轮虫、尾突臂尾轮虫和镰状臂尾轮虫与其它臂尾轮虫间的系统关系.  相似文献   
9.
【目的】本研究旨在利用已获得的PacBio单分子实时(single molecule real-time, SMRT)测序数据对蜜蜂球囊菌Ascosphaera apis菌丝(AaM)和孢子(AaS)中的转录因子(TF)、融合基因和RNA编辑事件进行鉴定和分析,以期丰富蜜蜂球囊菌的相关信息,并为进一步探究它们的功能提供理论依据。【方法】利用BLASTx工具将AaM和AaS的全长转录本序列比对到Nr, Swiss-Prot和KEGG数据库以获得一致性最高的蛋白序列,再利用hmmscan软件将上述蛋白序列比对到Plant TFdb数据库以获得TF的分类及注释信息。采用TOFU软件中的fusion_finder.py程序进行融合基因的预测,进而分析融合基因的序列和位置信息。使用SAMtools预测AaM和AaS中的RNA编辑事件,再利用ANNOVAR软件对RNA编辑事件进行注释,进而采用相关生物信息学软件对RNA编辑位点基因进行GO功能和KEGG通路注释。【结果】在AaS中共鉴定到17个TF家族的213个TF,其中C2H2家族包含的TF成员最多。在AaM和AaS中分别鉴定到921和510个融合基因,二者共有的融合基因为510个,特有的融合基因分别为411和0个。在AaM和AaS中分别鉴定到547和191次RNA编辑事件,其中AaM中同义单核苷酸突变的数量最多,AaS中非同义单核苷酸突变的数量最多。此外,在AaM中鉴定到12种碱基替换类型,其中发生C->T的RNA编辑事件数量最多,达到158次;在AaS中鉴定到9种碱基替换类型,其中发生C->T和G->T的RNA编辑事件数量最多,均有42次。AaM和AaS中RNA编辑位点基因分别涉及19和24个GO功能条目;此外还能注释到11和20条KEGG通路。【结论】蜜蜂球囊菌的菌丝和孢子中含有丰富的TF、融合基因和RNA编辑位点;转录因子C2H2家族与蜜蜂球囊菌菌丝和孢子的生长发育和细胞活动具有潜在关联;RNA编辑事件的碱基替换类型在蜜蜂球囊菌和其他物种中具有物种特异性;RNA编辑可能在蜜蜂球囊菌菌丝和孢子的生长和代谢中发挥作用。  相似文献   
10.
The regimen of cytarabine, aclarubicin and G-CSF (CAG) has been widely used in China and Japan for treatment of acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS). We searched literature on CAG between 1995 and 2010 and performed a meta-analysis to determine its overall efficacy using a random-effects or fixed-effects model. Thirty five trials with a total of 1029 AML (n = 814) and MDS (n = 215) patients were included for analysis. The CR rate of AML (57.9%) was significantly higher than that of MDS (45.7%) (p < 0.01). No difference in CR was noted between the new (56.7%) and relapsed/refractory AML (60.1%) (p > 0.05). The CR rate was also significantly higher in patients with favorable (64.5%) and intermediate (69.6%) karyotypes than those with unfavorable one (29.5%) (p < 0.05). Remarkably, the CR rate of CAG was significantly higher than those of non-CAG regimens (odds ratio 2.43). CAG regimen was well tolerated, with cardiotoxicity in 2.3% and early death in 5.2% of the cases. In conclusion, CAG regimen was an effective and safe regimen for the treatment of AML, and may be more effective than non-CAG regimens. Randomized controlled trials are strongly recommended to evaluate its efficacy and safety in comparison with the current standard treatment.  相似文献   
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