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82.
LU Na BAI Rui-ying WEI Lin-yu LI Chao-kun LI Xin-juan ZHAO Hong-gang LI Dong-liang 《园艺学报》2014,30(8):1388-1393
AIM:To examine the effects of high concentration of extracellular ATP on human neuroblastoma SH-SY5Y cell injury. METHODS:Cultured SH-SY5Y cells were grouped according to the concentrations of ATP and treatment time. The cell viability was detected by CCK-8 assay. The variation of autophagic vacuoles was observed with monodansylcadaverine staining. The cell apoptosis was analyzed by Hoechst 33258 staining. Meanwhile, apoptotic rate was detected by flow cytometry. The levels of caspase-3 and microtubule-associated protein 1 light chain 3-Ⅱ (LC3-Ⅱ) were determined by Western blotting. RESULTS:Compared with control group, the survival rate of SH-SY5Y cells was significantly reduced by ATP at different concentrations (3, 6, 9, 12 and 15 mmol/L for 3 h) and different treatment time (1, 2, 3 and 6 h with 6 mmol/L ATP, peaking at 3 h). The autophagic vacuoles of SH-SY5Y cells were significantly increased at 1 h with ATP treatment, trended to decrease over time and returned to control level at 6 h. The protein expression of LC3-Ⅱ was significantly increased at 1 h with ATP treatment, which was consistent with the time points of increasing autophagic vacuoles. LC3-Ⅱ expression level gradually decreased at 2~3 h with ATP treatment, and returned to control level at 6 h. Compared with control group, the apoptotic rate and the expression level of caspase-3 were enhanced synchronously. The peak of apoptotic rate occurred at 3 h, and kept until 6 h.The level of cleaved caspase-3 expression peaked at 6 h. CONCLUSION:High concentration of extracellular ATP induces the autophagy and apoptosis of SH-SY5Y cells. The increased autophagy shows up, followed by the climax of apoptosis until 6 h. With the prolonged duration of ATP, apoptosis is the main process in the cells. 相似文献
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Motobu M El-Abasy M Na KJ Vainio O Toivanen P Hirota Y 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2003,65(1):35-42
It has been suggested that the sympathetic nervous system communicates with lymphocytes expressing cell surface receptors for neurotransmitters such as norepinephrine (NE), on the basis of the finding that neurotransmitters modify immune responses in mammalian species. We confirmed that chicken lymphocytes in the brusa of Fabricius, thymus and spleen expressed beta-adrenergic receptor (beta-AR) mRNA from embryonic day (E) 10 and that intracellular cAMP level was elevated by NE, suggesting that lymphocytes express functional beta-AR on their surface at an early embryonal stage. To clarify whether the nervous system is involved in the development of the immune system, the effects of 6-hydroxydopamine (6-OHDA), one of sympathectomizing agents, on chicken lymphocytes was investigated. A single injection of 6-OHDA at a dose of 400 microg into a chicken embryo was carried out at E7 or 14 (as referred to E7 group and E14 group, respectively). NE level and the relative proportion of Bu-1a(+), CD4(+) and CD8(+) cells in the spleen of 3-week-old chickens were not altered by 6-OHDA treatment. However, the proliferative responses and expression of IL-2 mRNA in spleen cells cultured with pokeweed mitogen were reduced in E7 group compared with those of control. Furthermore, in CD8(+) spleen cells of E14 group of 3-week-old chickens, the expression of beta-AR mRNA and the relative increase of intracellular cAMP stimulated with NE were significantly decreased. These results suggest that the sympathetic nervous system affects the development of the immune system. 相似文献
86.
干旱是影响草地早熟禾生产力的主要因素之一。在没有参考基因组的情况下, 为了揭示草地早熟禾在干旱处理下基因表达谱的变化, 本文采用了高通量Illumina Hiseq测序平台对草地早熟禾的对照组(CK)与干旱处理组(D)进行转录组测序, 并对测序数据进行了分析研究, 进一步探究了草地早熟禾干旱应答的分子机制。结果表明, 在干旱处理下共检测到24465个差异表达的基因, 筛选后获得4143个上调基因和4415个下调基因, 共占差异表达基因总数的34.98%。经富集分析后得, 与蛋白激酶、蛋白磷酸酶、碳代谢以及ABA等相关的基因可以作为研究草地早熟禾干旱响应机制的主要研究对象。qRT-PCR分析表明, 随机选出的8个差异性表达基因的表达趋势与高通量测序结果相一致。此外, 还候选了吲哚-3-甘油磷酸合成酶、蛋白磷酸酶、已糖激酶、钙结合蛋白、叶绿素a/b结合蛋白等基因作为与草地早熟禾干旱胁迫相关的应答候选基因, 为揭示草地早熟禾耐旱分子机制奠定了基础。 相似文献
87.
Detection of mitogen-induced lymphocyte proliferation by bromodeoxyuridine (BrdU) incorporation in the chicken 总被引:2,自引:0,他引:2
Motobu M El-Abasy M Na KJ Hirota Y 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2002,64(4):377-379
3H-thymidine (3H-TdR) incorporation assay has been generally used to measure lymphocyte proliferation in the chicken. Disadvantages of this assay are that radioisotope is biological hazard to the person and environment and that it can not measure which subset of lymphocytes proliferates. In this study, bromodeoxyuridine (BrdU) incorporation assay by flow cytometry was compared with 3H-TdR incorporation assay. As a result, BrdU incorporation assay showed a strong correlation with 3H-TdR incorporation assay, and it could be applied simultaneously to detect BrdU incorporation and expression of cell surface marker antigens. These results suggest that the BrdU incorporation assay by flow cytometry is useful to analyze lymphocyte proliferation in detail. 相似文献
88.
Hang Ryeol Na Gordon M. Heisler David J. Nowak Richard H. Grant 《Urban Forestry & Urban Greening》2014,13(4):785-792
A mathematical model is constructed for quantifying urban trees’ effects on mitigating the intensity of ultraviolet (UV) radiation on the ground within different land use types across a city. The model is based upon local field data, meteorological data and equations designed to predict the reduced UV fraction due to trees at the ground level. Trees in Seoul, Korea (2010), produced average UV protection factors (UPF) for pedestrians in tree shade at solar noon (May to August) of 8.3 for park and cemetery land uses and 3.0 for commercial and transportation land uses. The highest daily UPF was 11.8 in the park and cemetery land uses, which has the highest percent canopy cover. This UV model is being implemented within the i-Tree modeling system to allow cities across the world to estimate tree effects on UV exposure. Understanding the impacts of urban trees on UV exposure can be used in developing landscape design strategies to help protect urban populations from UV exposure and consequent health impacts. 相似文献
89.
黄河表层沉积物与稀土元素La~(3+)的交换吸附作用研究 总被引:3,自引:0,他引:3
采用现场采样及室内实验方法,研究了黄河表层沉积物与La^3 的交换吸附作用。结果表明,用Langmuir方程和Freundlich方程均能较好地反映La^3 在沉积物表面上的等温吸附过程,但以Langmuir方程拟合程度更好,黄河表层沉积物对La^3 的吸附强烈地受控于pH值在2-12这一宽广的pH范围内,La^3 黄河表层沉积物的交换吸附呈现随pH的增加而增大的总体趋势,在pH为2-7的范围内,随pH的增大,La^3 的吸附量逐渐增加,并在pH为6-7时达到最高值;当pH>7时,随Ph的增大,La^3 的吸附量基本保持恒定,沉积物去除有机质后吸附能力下降了12.71%,与颗粒物中稀上元素有机物结合态所占比例相当. 相似文献
90.
龟裂碱土对不同基因型甜高粱幼苗生长和生理特性的影响 总被引:1,自引:0,他引:1
为探明甜高粱幼苗对龟裂碱土胁迫的响应,通过盆栽试验,以5个不同基因型的甜高粱为材料,研究了龟裂碱土对甜高粱幼苗生长和生理特性的影响。结果表明,龟裂碱土抑制了甜高粱幼苗的生长,显著降低了甜高粱幼苗株高、根长和植株干重。龟裂碱土胁迫条件下,不同基因型甜高粱叶绿素含量和光合速率均大幅度降低,而叶片质膜相对透性、MDA含量以及SOD、POD、CAT等保护性酶活性则显著升高。不同基因型甜高粱对龟裂碱土胁迫的耐受能力存在较大差异,品种ZNH05耐盐碱能力较差,ZNH07和ZNH18则表现出较强的耐盐碱性。 相似文献