Val 70, Phe 72 and the last seven amino acid residues of C-terminal are essential to the function of norepinephrine transporter

The norepinephrine transporter(NET) is a member of the Na+/Cl- dependent neurotransmitter transporter family and constitutes the target of several clinically important antidepressants. To delineate the critical amino acid residues and the function of C-terminal in regulating transport activity of NET, here we constructed two site mutants (V70F, F72V; V70I, F72V) and one C-terminal truncated mutant (△611-617). The wild type and mutants of NET were expressed in Xenopus oocytes by injection of their cRNA. We found that all of these mutants lost their transport activity. These results indicate that the amino acid residues of V70 and F72 3 and the last seven amino acids of C-terminal are essential to the transport activity of NET.

C_(72)的结构、电子光谱及非线性光学性质的理论研究

用密度泛函 (DFT)方法 (BLYP/3 2 1g )研究了C72 的三种几何构型 .用ZINDO及abinitioCIS两种方法对C72 的电子光谱进行了计算 ,预测C72 在 13 5 0nm处的光谱吸收是由HOMO→LUMO的跃迁引起的 ,在 2 3 0nm左右 ,存在最强吸收峰 .计算了三种构型的C72 的二阶、三阶非线性光学系数 ,并分别进行了比较 .

Ca@C_(72)的结构、电子光谱及非线性光学性质的理论研究

用密度泛函 (DFT)方法 (BLYP/3 2 1G )研究了Ca @C72 的三种异构体 .用ZINDO方法对Ca @C72 的电子光谱进行了计算 ,Ca @C72 在 12 0 0～ 14 0 0nm范围内的光谱吸收是由HOMO→LUMO的跃迁引起的 .其最强吸收在 2 3 0nm左右 ,与实验值吻合较好 .同时计算了三种构型的二阶、三阶非线性光学系数 ,并与C72 和Ca @C74进行了比较 ,预测Ca @C72 是较好的非线性光学材料 .

热休克蛋白72抑制ATP耗竭时细胞色素C释放所诱导的肾小管上皮细胞凋亡

目的 研究热休克蛋白(HSP)72对ATP耗竭时细胞色素C释放所导致的肾小管上皮细胞凋亡的保护作用及其分子机制。方法 应用代谢抑制剂暂时性阻断细胞内ATP的生成,引起细胞凋亡。应用热处理细胞或编码HSP72 RNA的腺病毒感染细胞,诱导HSP72的表达。以Western印迹检测释放于胞浆内的细胞色素C。荧光肽法测定半胱氨酸天冬氨酸蛋白酶(caspase)3活性。Hoechst33342染色观察细胞凋亡的发生情况。结果 肾小管上皮细胞内ATP耗竭时,释放至胞浆内的细胞色素C的含量增多,caspase 3活性增强;细胞内ATP再恢复时,细胞色素C的释放和caspase 3活性进一步增加,细胞体积缩小,核浓染、固缩,形成凋亡小体。预先热处理后,各组细胞色素C的释放明显减少,caspase 3活性显著抑制(P<0.05,n=3)。高表达HSP72时,各时间点caspase 3活性的抑制程度与热处理组相似,细胞体积缩小,核浓染、固缩,凋亡小体的形成明显减少。结论 HSP72可抑制ATP耗竭时细胞色素C所导致的肾小管上皮细胞凋亡,其机制是抑制凋亡通路中细胞色素C的释放和caspase 3的激活。

Nitric oxide induces heat shock protein 72 production and delayed protection against myocardial ischemia in rabbits via activating protein kinase C

Background Nitric oxide （NO） is a biologically active molecule which has been reported to protect the heart against ischemia and reperfusion injury in different species. This study aimed to test the hypothesis that nitric oxide may induce the expression of heat shock protein 72 （HSP72） which may protect the heart against ischemia.Methods Rabbits were given intravenous saline or S-nitroso-N-acetylpenicillamine （SNAP）, a nitric oxide donor, or Zaprinast, an inhibitor of cyclic guanosine monophosphate （GMP）-phosphodiesterase, which may increase myocardial cyclic GMP content. Twenty-four hours later, the rabbits were either sampled to measure HSP72, or induced with a 30-minute coronary occlusion followed by a 120-minute reperfusion, and then the infarct size was measured. Meanwhile, chelerythrine （CHE, an inhibitor of protein kinase C） was given intravenously 5 minutes before SNAP injection and the effect on HSP72 expression and infarct size was determined.Results Twenty-four hours after pretreatment, immunoblotting showed HSP72 expression increased in the SNAP group compared with control groups, and this was blocked by CHE. Myocardial infarct size in the SNAP group was smaller than that of the control group （（32.4±5.8）% vs （51.1±4.7）%, P 〈0.05）. Pretreated with CHE abolished the infarct size-limiting effect of SNAP （（46.0±5.1）%）. Pretreatment with Zaprinast neither induced HSP72 expression nor reduced infarct size （（55.4±5.4）%）.Conclusion NO induced HSP72 expression and a delayed protection to the heart via the activities of protein kinase C by a cyclic GMP-independent pathway.

胃蛋白酶原联合肿瘤标志物检测对健康人群胃癌发生的预测价值

目的探讨胃蛋白酶原、CA72-4、CEA、CRP联合检测在胃癌诊断中的应用。方法选取2014年11月-2016年6月本院收治的胃癌患者59例、萎缩性胃炎患者55例纳入本研究,另选取本院同期健康体检者50例为对照组。检测相关指标并进行比较,其中AUC值采用Medcalc计算。结果胃癌组PGⅠ水平、PGⅡ水平、PGR显著低于萎缩性胃炎组、对照组,胃癌组CA72-4、CEA、CRP水平显著高于萎缩性胃炎组、对照组。血清胃蛋白酶原及CA72-4、CEA、CRP联合检测胃癌中灵敏度为93.57%、阳性预测值为95.85%、阴性预测值为89.97%以及准确度为93.43%,均显著高于单项检测,上述差异均有统计学意义(P<0.05)。各指标联合检测胃癌AUC值为0.942,与其他指标相比,差异有统计学意义(P<0.05)。结论胃蛋白酶原、CA72-4、CEA、CRP联合检测优于单项检测,在胃癌诊断中可显著提高检测的灵敏度,且准确度高,值得推广应用。