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171.
Ma J  Zhang L  Han W  Shen T  Ma C  Liu Y  Nie X  Liu M  Ran Y  Zhu D 《Journal of lipid research》2012,53(6):1093-1105
Pulmonary artery endothelial plexiform lesion is responsible for pulmonary vascular remodeling (PVR), a basic pathological change of pulmonary arterial hypertension (PAH). Recent evidence suggests that epoxyeicosatrienoic acid (EET), which is derived from arachidonic acid by cytochrome p450 (CYP) epoxygenase, has an essential role in PAH. However, until now, most research has focused on pulmonary vasoconstriction; it is unclear whether EET produces mitogenic and angiogenic effects in pulmonary artery endothelial cells (PAEC). Here we found that 500 nM/l 8,9-EET, 11,12-EET, and 14,15-EET markedly augmented JNK and c-Jun activation in PAECs and that the activation of c-Jun was mediated by JNK, but not the ERK or p38 MPAK pathway. Moreover, treatment with 8,9-EET, 11,12-EET, and 14,15-EET promoted cell proliferation and cell-cycle transition from the G0/G1 phase to S phase and stimulated tube formation in vitro. All these effects were reversed after blocking JNK with Sp600125 (a JNK inhibitor) or JNK1/2 siRNA. In addition, the apoptotic process was alleviated by three EET region isomers through the JNK/c-Jun pathway. These observations suggest that 8,9-EET, 11,12-EET, and 14,15-EET stimulate PAEC proliferation and angiogenesis, as well as protect the cells from apoptosis, via the JNK/c-Jun pathway, an important underlying mechanism that may promote PAEC growth and angiogenesis during PAH.  相似文献   
172.
Ma H  Li H  Jin G  Dai J  Dong J  Qin Z  Chen J  Wang S  Wang X  Hu Z  Shen H 《DNA and cell biology》2012,31(6):1114-1120
A single nucleotide polymorphism (SNP) rs999737 at 14q24.1 was identified as a susceptibility marker of breast cancer in a genome-wide association study of the European population, which was also confirmed by some of the following studies in populations of European descent. However, rs999737 is very rare or nonpolymorphic in non-Europeans including Chinese, and the role of other genetic variants at 14q24.1 has not been evaluated in populations of non-European descent. In this study, we first selected 21 common tagging SNPs (minor allele frequency [MAF] >0.05 in the Chinese population) by searching the Hapmap database, covering a linage disequilibrium region of more than 70?Kb at 14q24.1, and then conducted a two-stage study (stage I: 878 cases and 900 controls; stage II: 914 cases and 967 controls) to investigate the associations between these tagging SNPs and risk of breast cancer in a Chinese population. In stage I, two SNPs (rs2842346 and rs17828907) were identified to be significantly associated with breast cancer risk (p=0.030 and 0.027 for genotype distributions, respectively). However, no significant associations were found between these two SNPs and breast cancer risk in either stage II or the combined dataset. These findings suggest that common variants at 14q24.1 might not be associated with the risk of breast cancer in the Chinese population, which will need the replication in additional larger studies.  相似文献   
173.
目的建立一种简单快速观察腹腔内接种包虫病动物模型的方法。方法按2000个原头节/mL剂量,用多房棘球蚴对灰仓鼠进行腹腔接种,采用肉眼观察法和显微镜镜检法在第10天,15天,18天,22天,39天和60天观察灰仓鼠腹腔内包囊、包囊液和原头节的生长情况;设空白对照组10只。结果通过肉眼观察和显微镜镜检,发现灰仓鼠在接种后的第18天有原头蚴生长;第15天,18天和22天包囊增大、增多;第39天有成熟原头节胚基生长;第60天有不同发育程度的原头蚴。随着接种时间的延长,包囊重量与传代时间成正比。结论本试验为制备包虫病动物模型提供了简单快速的观察方法。  相似文献   
174.
175.
Luo GM  Qi DH  Zheng YG  Mu Y  Yan GL  Yang TS  Shen JC 《FEBS letters》2001,492(1-2):29-32
The free radicals generated from the iron containing system of xanthine oxidase and hypoxanthine (Fe-XO/HX) were directly detected by using spin trapping. It was found that not only superoxide anion (O(2)*-) and hydroxyl radical (OH*), but also alkyl or alkoxyl radicals (R*) were formed when saccharides such as glucose, fructose and sucrose were added into the Fe-XO/HX system. The generated amount of R* was dependent on the kind and concentration of saccharides added into the Fe-XO/HX system and no R* were detected in the absence of saccharides, indicating that there is an interaction between the saccharide molecules and the free radicals generated from the Fe-XO/HX system and saccharide molecules are essential for generating R* in the Fe-XO/HX system. It is expected that the toxicity of R* would be greater than of hydrophilic O(2)*- and OH* because they are liposoluble and their lives are longer and the active sites of biomolecules are closely related with lipophilic phase, thus they can damage cells more seriously than O(2)*- and OH*. The R* generated from the saccharide containing Fe-XO/HX can be effectively scavenged by selenium containing abzyme (Se-abzyme), indicating Se-abzyme is a promising antioxidant.  相似文献   
176.
棉铃虫对Bt生物农药早期抗性及与转Bt基因棉抗虫性的关系   总被引:19,自引:0,他引:19  
用饲料感染法建立了棉铃虫Helicoverpa rmigera(Hubmer)敏感品系(SUS1)对Bt生物农药的敏感毒力基线和区分剂量,1995年测定了五省六县棉铃虫初孵幼虫对Bt生物农药的敏感性,结果表明:山东阳谷、河北邯郸、河南新乡、安徽萧县及江苏丰县棉铃虫已产生早期抗性,抗性个体百分率为5%~10%,与敏感品系相比,LC50值稍有增加,但斜率b值明显变小;而江苏东台棉铃虫仍属敏感。这是国内外首次诊测到棉铃虫对Bt生物农药抗性。用棉叶喂饲法测定比较了转Bt基因棉花品系对不同种群棉铃虫的抗虫性效果,结果表明:用早期抗性的阳谷和新乡棉铃虫初孵幼虫接虫5d后平均死亡率较敏感品系下降16%~29%,说明棉铃虫对Bt农药与转Bt生物基因棉花品系间存在交互抗性。还讨论了Bt农药的抗性治理对策。  相似文献   
177.
178.
【目的】热带假丝酵母是发酵法生产二元酸的重要工业菌株,具有较高的ω-氧化活性。脂肪醛脱氢酶在ω-氧化途径中起重要作用,催化脂肪醛生成脂肪酸,但其具体催化功能及对细胞生理影响还未被系统研究。本文通过删除脂肪醛脱氢酶基因CtAld1和CtAld2鉴定了其在ω-氧化途径中的功能。【方法】通过基因组信息挖掘获得热带假丝酵母脂肪醛脱氢酶基因CtAld1和CtAld2序列,在此基础上,通过同源重组敲除CtAld1和CtAld2基因。考察突变株的生长和胞内脂肪醛脱氢酶活性变化,并评价CtAld1和CtAld2基因敲除对细胞二元酸合成能力的影响。【结果】分别获得了热带假丝酵母突变株XZX-1(ΔCtAld1/ΔCtAld1)、XZX-2(ΔCtAld2/ΔCtAld2)和XZX-12(ΔCtAld1/ΔCtAld1,ΔCtAld2/ΔCtAld2)。在以十二烷为唯一碳源的培养基中,敲除CtAld2基因显著抑制细胞的生长,胞内脂肪醛脱氢酶活性降低为出发菌株的30%;敲除CtAld1基因尽管会使细胞损失一部分醛脱氢酶活性,但能够一定程度地提升细胞在十二烷中的生长性能。敲除CtAld1或CtAld2会降低菌株二元酸产量,组合敲除CtAld1和CtAld2严重削弱菌株十二碳二元酸的合成能力。【结论】CtAld2对热带假丝酵母细胞的生长和十二碳二元酸的合成具有重要作用,缺失CtAld1或CtAld2基因降低细胞的二元酸合成能力。CtAld1和CtAld2可作为热带假丝酵母ω-氧化途径代谢工程改造的潜在靶点。  相似文献   
179.
The neural cell adhesion molecule (NCAM) plays a pivotal role in the development and maintenance of the nervous system via homophilic (NCAM–NCAM) and heterophilic (NCAM-other molecules) interactions. Many synthetic peptides have been engineered to mimic these interactions and induce NCAM-downstream signaling pathways. Such NCAM mimetics have displayed neuritogenic and neuroprotective properties, as well as synaptic modulation in vitro and in vivo. Furthermore, they have been used successfully in preclinical studies to treat neurological disorders including stroke, traumatic brain injury and Alzheimer’s disease. This review focuses on recent progress in the development of NCAM mimetic peptides, in particular, on establishing C3, plannexin, and FGL as therapeutic candidates for neurological disorders.  相似文献   
180.
生物复苏——大绝灭后生物演化历史的第一幕   总被引:11,自引:1,他引:11  
生命史是一部生物界短期,快速剧变与长期,慢速稳定相互交替的历史。大绝灭(即集群绝灭)事件反映了全球环境的大突变,点断了地质历史中的生命记录及其发展历程,预示着生物界的演化出现了最有意义的飞跃,近年来尝试研究大绝灭后全球生物界的残存-复苏及其基本型式,并探索复苏的控制因素,标志着地质科学中一个重心的转移(即从大绝灭转向其后的生物残存与复苏的研究)。生物复苏揭示了大绝灭后生物演化历史的第一幕,其研究的  相似文献   
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