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991.
992.
Hua Zhang Jian-Hua Yang Yu-Sheng Zheng Peng Zhang Xiao Chen Jun Wu Ling Xu Xue-Qun Luo Zhi-Yong Ke Hui Zhou Liang-Hu Qu Yue-Qin Chen 《PloS one》2009,4(9)
Background
MicroRNAs (miRNAs) have been proved to play an important role in various cellular processes and function as tumor suppressors or oncogenes in cancers including leukemia. The identification of a large number of novel miRNAs and other small regulatory RNAs will provide valuable insights into the roles they play in tumorgenesis.Methodology/Principal Findings
To gain further understanding of the role of miRNAs relevant to acute lymphoblastic leukemia (ALL), we employed the sequencing-by-synthesis (SBS) strategy to sequence small RNA libraries prepared from ALL patients and normal donors. In total we identified 159 novel miRNAs and 116 novel miRNA*s from both libraries. Among the 159 novel miRNAs, 42 were identified with high stringency in our data set. Furthermore, we demonstrated the different expression patterns of 20 newly identified and several known miRNAs between ALL patients and normal donors, suggesting these miRNAs may be associated with ALL and could constitute an ALL-specific miRNA signature. Interestingly, GO “biological process” classifications revealed that a set of significantly abnormally expressed miRNAs are associated with disease relapse, which implies that these dysregulated miRNAs might promote the progression of ALL by regulating genes involved in the pathway of the disease development.Conclusion/Significance
The study presents a comprehensive picture of the expression of small RNAs in human acute lymphoblastic leukemia and highlights novel and known miRNAs differentially expressed between ALL patients and normal donors. To our knowledge, this is the first study to look at genome-wide known and novel miRNA expression patterns in in human acute lymphoblastic leukemia. Our data revealed that these deregulated miRNAs may be associated with ALL or the onset of relapse. 相似文献993.
994.
目的:研究孤啡肽(N/OFQ)对大鼠顶叶皮层神经元瞬时外向钾电流(IA)的影响,初步探讨其作用的通道动力学机制。方法:采用全细胞膜片钳技术,观察N/OFQ对急性分离的大鼠顶叶皮层神经元IA的作用。结果:①0.1μmol/L N/OFQ使IA幅值由给药前的(5356.1±361.6)pA下降为(4113.3±312.7)pA,抑制率为23.20%±2.17%(P〈0.01,n=10)。②0.1μmol/L N/OFQ使IA的电流-电压(I-V)曲线降低(P〈0.01,n=10)。③0.1μmol/L N/OFQ使,IA激活曲线的半数激活电压(V1/2)和斜率因子(κ)分别由给药前的(-9.2±2.5)mV和(20.4±2.3)mV变为给药后的(30.6±3.7)mV(P〈0.01,n=8)和(22.6±2.1)mV(P〉0.05,n=8)。④0.1μmol/L N/OFQ使IA失活曲线的半数失活电压(V1/2)和斜率因子(κ)分别由给药前的(-64.1±3.2)mV和(21.5±2.1)mV变为给药后的(-55.9±1.9)mV(P〈0.05,n=5)和(19.6±2.2)mV(P〉0.05,n=5)。结论:N/OFQ可抑制大鼠顶叶皮层神经元IA,使其激活曲线、失活曲线均右移。 相似文献
995.
旨在研究蛋白G IgG Fc段结合域(PGFB)的克隆、表达及其抗体结合功能,用于抗体的纯化.根据PGFB的氨基酸序列,选择大肠杆菌偏爱的密码子,设计并合成了4个寡核苷酸片段.通过重叠延伸PCR方法合成了PGFB DNA片段,测序鉴定后克隆至原核表达系统pET-28a-c(+)上,转化大肠杆菌,获得表达菌株;IPTG诱导表达PGFB,经Ni+-NTA琼脂糖凝胶层析纯化后偶联到琼脂糖凝胶6B上,用其纯化多克隆抗体.结果显示,PGFB在大肠杆菌BL21(DE3)中获得高效表达,纯化后纯度达到90%以上,相对分子量为12.25 kD,与预期值相符.此外,偶联产物纯化多克隆抗体达到了良好的效果,每毫升基质可结合20 mg抗体.本研究克隆构建并高效表达了具有较好抗体亲和能力的PGFB,为多克隆抗体的快速纯化提供了方便. 相似文献
996.
997.
998.
Huan Zhang Yong-an Zhang Qilian Qin Xuan Li Lin Miao Yuzhu Wang Liangjian Qu Aijun Zhang Qing Yang 《In vitro cellular & developmental biology. Animal》2009,45(5-6):201-204
A cell strain (IOZCAS-Spex-II-A) cloned from IOZCAS-Spex-II, a cell line established from the fat body of Spodoptera exigua (Lepidoptera: Noctuidae) larva, was characterized, and its capability to produce S. exigua nucleopolyhedrovirus was high with infection rate exceeding 90% compared with its parental cell line IOZCAS-Spex-II that scored only 50%. Growth curve of budded virus (BV) in the strain was analyzed and the titer of BV reached the highest of 3.7?×?104 pfu/mL by 96 h after inoculation. Concentration of occlusion bodies (OBs) produced by the cloned cell strain (IOZCAS-Spex-II-A) was 7.1?×?107 OBs/mL, while the parental cell line produced 2.4?×?107 OBs/mL. The average yield of the virus was 176 OBs/cell of IOZCAS-Spex-II-A compared with 211 OBs/cell that of the parental cell line. Significant differences were observed in virus production, growth characters, cell shape, between the parental cell line, and its clone. The cell lines (IOZCAS-Spex-II and IOZCAS-Spex-II-A) were also susceptible to Autographa californica multiple nucleopolyhedrovirus infection. In addition, they were characterized with regard to their growth rates and DNA amplification fingerprinting technique employing polymerase chain reaction. 相似文献
999.
1000.
Wei Qu Yabin Zhou Chunhong Shao Yundong Sun Qunye Zhang Chunyan Chen Jihui Jia 《Journal of microbiology (Seoul, Korea)》2009,47(4):486-493
Helicobacter pylori is a highly pathogenic microorganism with various strategies to evade human immune responses. Nitric oxide (NO) and reactive nitrogen species (RNS) generated via nitric oxide synthase pathway are important effectors during the innate immune response. However, the mechanisms of H. pylori to survive the nitrosative stress are not clear. Here the proteomic approach has been used to define the adaptive response of H. pylori to nitrosative stress. Proteomic analysis showed that 38 protein spots were regulated by NO donor, sodium nitroprusside (SNP). These proteins were involved in protein processing, anti-oxidation, general stress response, and virulence, as well as some unknown functions. Particularly, some of them were participated in iron metabolism, potentially under the control of ferric uptake regulator (Fur). Real time PCR revealed that fur was induced under nitrosative stress, consistent with our deduction. One stress-related protein up-regulated under nitrosative conditions was thioredoxin reductase (TrxR). Inactiva-tion of fur or trxR can lead to increased susceptivity to nitrosative stress respectively. These studies described the adaptive response of H. pylori to nitric oxide stress, and analyzed the relevant role of Fur regulon and TrxR in nitrosative stress management. 相似文献