作者机构：
[Li, Sidi; Shi, Zhe; Liu, Xinmin] Chinese Acad Med Sci, Res Ctr Pharmacol & Toxicol, Inst Med Plant Dev IMPLAD, Beijing 100193, Peoples R China.;[Li, Sidi; Shi, Zhe; Liu, Xinmin] Peking Union Med Coll, Beijing 100193, Peoples R China.;[He, Yiran; Chen, Lingling; Zeng, Jianguo] Hunan Univ Tradit Chinese Med, Changsha 410208, Hunan, Peoples R China.;[Chen, Shanguang; Li, Yinghui] China Astronaut Res & Training Ctr, Beijing 100094, Peoples R China.;[Sun, Xiuping] Peking Union Med Coll, Comparat Med Ctr, Beijing 100021, Peoples R China.
通讯机构：
[Liu, Xinmin] C;Chinese Acad Med Sci, Res Ctr Pharmacol & Toxicol, Inst Med Plant Dev IMPLAD, Malianwa North Rd 151, Beijing 100193, Peoples R China.
摘要：
Scopolamine, a nonselective muscarinic receptor antagonist, has been used in experimental animal models of dementia. It has been demonstrated to disrupt performances in a battery of behavioral tests. However, no attempt has been made to determine how scopolamine-treated animals would respond to a series of reward-directed instrumental learning (RDIL) tasks. The present study was designed to investigate the effects of chronic intraperitoneal injection of scopolamine in Wistar rats on RDIL, as well as on the expression of memory-related molecules in the dorsal hippocampus (DH) and cerebral cortex (CCx). The effects of the pretraining injection of scopolamine on the acquisition of instrumental response (experiment 1) were first investigated. Then, the effects of post-training manipulation on the maintenance of instrumental response and the responses to changes in contingency degradation and signal discrimination were assessed (experiment 2). Finally, the expression of cyclic AMP response element-binding protein (CREB), phosphorylated CREB, and brain-derived neurotrophic factor in the DH and CCx were examined using Western blotting and enzyme-linked immunosorbent assay. The acquisition of instrumental conditioning is more vulnerable than its maintenance. The 3.0-mg/kg dose of scopolamine rendered rats unable to make adaptive changes in facing contingency degradation and correct responses in signal discrimination tasks. Furthermore, CREB signaling was inactivated by pretraining scopolamine treatment in both the DH and CCx. Nevertheless, this pathway was selectively suppressed by post-training treatment only in the CCx during memory reconsolidation. The results suggest that scopolamine-induced cognitive deficits on RDIL are related to the distinguishing alteration of CREB signaling in the DH and CCx.
摘要：
The series piezoelectric quartz crystal (SPQC) sensing technique is a rapid and sensitive method for detection of microorganisms. In the present study, the detection device was composed of detecting system, signal generating system and data analyzing system. To magnify the amount of detection samples, eight independent SPQC sensors were parallel connected to form a muti-channel detecting unit. Electrodes were separated from the SPQC sensor and immersed into culture medium to detect the change of solution conductivity. The cell constant k was determined as 0.05 m, and the sensitivity interval of the device was from 550 to 600 μs. To maintain sensitivity of the SPQC sensor, a novel culture medium amino acid broth (AaB) was developed. It was nutrient with low conductivity and satisfied our detection device. For determining frequency detection time (FDT) expediently and accurately, FDT was defined afresh with fitting–differentiating method. Pathogens Staphylococcus aureus and Shigella dysenteriae were determined with an automated detecting device and the methods mentioned above. The calibration curves of FDT against density of bacteria showed a linear correlation coefficient (R ≥ 0.99) over the range of 10–106 cells ml−1. Detection results all fell inside the 95% confidence interval of a standard pour plate counting method. The reproducibility was also reviewed, and results showed that the device was stable and sensitive even after 180 days of employment.
摘要：
Apelin is the endogenous ligand of the G protein-coupled receptor, APJ. Vascular smooth muscle cells express both apelin and APJ, which are important regulatory factors in the cardiovascular and nervous systems. Importantly, APJ is also involved in the pathogenesis if HIV-1 infection. We investigated whether vascular smooth muscle cell proliferation was regulated through an apelin-pERK1/2-cyclin D1 signal transduction pathway. Apelin-13 significantly stimulated vascular smooth muscle cell proliferation and increased cell cycle progression. Apelin-13 a decreased the proportion of cell in the G0/G1 phase while increasing the number of cells in S phase. Apelin-13 also increased the levels of cyclin D1, cyclin E and pERK1/2. Treatment of cells with the MEK inhibitor PD98059 attenuated the apelin-3-induced pERK1/2 activation. Similarly, treatment with PD98059 partially diminished the apelin-13-induced expression of cyclin D1 and vascular smooth muscle cell proliferation. Taken together, these data established that apelin-13 stimulates vascular smooth muscle cell proliferation by promoting the G1-S phase transition, and that this effect is mediated in part by an apelin-pERK1/2-cyclin D1 signal cascade.
作者机构：
[Zhou, Hai-Bin; Gao, Zheng-Xi; Zhong, Chun-Long; Chen, Lei; Zhang, Yan-Hong; Yao, Zhu-Jun; Wu, Wen-Min] Chinese Acad Sci, Shanghai Inst Organ Chem, State Key Lab Bioorgan & Nat Prod Chem, Shanghai 200032, Peoples R China.;[Peng, Xin-Jun; Zhang, Yan-Hong] Hunan Tradit Chinese Med Univ, Dept Anal Chem, Changsha 410007, Hunan, Peoples R China.;[Zhong, Chun-Long; Yao, Zhu-Jun] Univ Sci & Technol China, Dept Chem, Anhua 230026, Peoples R China.;[Yao, Zhu-Jun] Chinese Acad Sci, Shanghai Inst Organ Chem, State Key Lab Bioorgan & Nat Prod Chem, 345 Fenglin Rd, Shanghai 200032, Peoples R China.
通讯机构：
[Yao, Zhu-Jun] C;Chinese Acad Sci, Shanghai Inst Organ Chem, State Key Lab Bioorgan & Nat Prod Chem, 345 Fenglin Rd, Shanghai 200032, Peoples R China.
摘要：
Labeling of bioactive small molecules with organic dyes for various applications in cell biology has been emerging as an attractive research field. Using an easily prepared and inexpensive fluorescein derivative 1 and a Cu(I)-catalyzed Huisgen reaction, an efficient fluorescent labeling strategy is developed generally for bioactive natural products. Essentials of a successful labeling include the personalized introduction of an azido functionality to specific targets by a selective and efficient manner, and the strategic adjustment of reaction sequence to avoid possible side reactions under the 'click' reaction conditions. Such a protocol has been successfully applied to the fluorescent labeling of four bioactive small molecules in different chemical categories in this study. Advantages of this labeling protocol include the use of inexpensive reagents, ease of operation, free-of-protections at the 'click' step, and suiting a wide range of bioactive molecules bearing the reactive functionalities. (c) 2007 Elsevier Ltd. All rights reserved.
