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911.
Liu XH Ruan BF Liu JX Song BA Jing LH Li J Yang Y Zhu HL Qi XB 《Bioorganic & medicinal chemistry letters》2011,21(10):2916-2920
A series of novel N-phenylacetyl (sulfonyl) 4,5-dihydropyrazole derivatives as potential telomerase inhibitors were synthesized. The bioassay tests show that compound 4a exhibited high activity against human gastric cancer cell SGC-7901, liver cancer Hep-G2 and human prostate PC-3 cell lines with IC50 values of 21.23 ± 0.99, 29.43 ± 0.32 and 30.89 ± 1.07 μM, respectively. All title compounds were assayed for telomerase inhibition by a modified TRAP assay, the results show that compound 4a can inhibit telomerase with IC50 value of 4.0 ± 0.32 μM. Docking simulation was performed to position compound 4a into the telomerase (3DU6) active site to determine the probable binding model. 相似文献
912.
Neurotoxin-1 (NT) is an analgesic peptide which is endowed an exceptional specificity of action that blocks transmission of the nerve impulse. The aim of this study was to evaluate the potential application of nanoparticles technology as drug carrier system for the nasal delivery of NT. Mice were administered intranasally (i.n.) with NT (NT-P-NP), free NT solution (F-NT) and intravenously (i.v.) with NT (IV-NT) respectively. The NT levels in animal brain and antinociceptive activity of NT were analyzed. The result on brain transport showed that nanoparticles could exert enhanced delivery of NT into the brain significantly after i.n. administration. The results of antinociceptive activity showed that NT-P-NP increased immobility in the open-field test, both phases of formalin test were significantly inhibited by the NT-P-NP and NT-P-NP significantly inhibited the reaction time to thermal stimuli at 60 and 90 min. Both NT-P-NP and IV-NT were able to inhibit constrictions in acetic acid-induced writhing reaction. These data suggest that NT-loaded nanoparticles coated with polysorbate-80 could generate a significant improvement of drug levels in the brain. Intranasal administration of Neurotoxin-1 entrapped in nanoparticles coated with polysorbate-80 is an attractive alternative to intravenous administration. 相似文献
913.
An antifungal peptide from Fagopyrum tataricum seeds 总被引:1,自引:0,他引:1
A major trypsin inhibitor was isolated and characterized from the seeds of the tartary buckwheat (Fagopyrum tataricum) (FtTI) by ammonium sulfate precipitation, ion exchange chromatography and centrifugal ultrafiltration. SDS-PAGE analysis under reducing condition showed that FtTI is a single polypeptide chain with a molecular mass of approximately 14 kDa. The complete amino acid sequence of FtTI was established by automatic Edman degradation and mass spectrometry. It was found that the trypsin inhibitor molecule consists of 86 amino acid residues containing two disulfide bonds which connect Cys8 to Cys65 and Cys49 to Cys58. The active site of the inhibitor was found to contain an Asp66-Arg67 bond. MALDI-TOF analysis showed that FtTI has two isoforms (Mr: 11.487 and 13.838 kDa). Dixon plots revealed a competitive inhibition of trypsin with inhibition constants (Ki) of 1.6 nM. Analysis of the amino acid sequence suggests that FtTI is a member of the protease inhibitor I family. What is more, FtTI exhibited strong inhibitory activity against phytopathogenic fungi. 相似文献
914.
915.
This paper is concerned with the spreading speeds and traveling wave solutions of discrete time recursion systems, which describe
the spatial propagation mode of two competitive invaders. We first establish the existence of traveling wave solutions when
the wave speed is larger than a given threshold. Furthermore, we prove that the threshold is the spreading speed of one species
while the spreading speed of the other species is distinctly slower compared to the case when the interspecific competition
disappears. Our results also show that the interspecific competition does affect the spread of both species so that the eventual
population densities at the coexistence domain are lower than the case when the competition vanishes. 相似文献
916.
The antiplatelet and antithrombotic effects of ent-16β,17-dihydroxy-kauran-19-oic acid (DDKA) isolated from Siegesbeckia pubescens were investigated with different methods both in vitro and in vivo. We tested the antithrombotic activity of DDKA in arterio-venous shunt model. The effects of DDKA on adenosine diphosphate (ADP)-, Thrombin-, Arachidonic acid-induced rat platelets aggregation were tested in vitro. We also assessed its bleeding side effect by measuring coagulation parameters after intravenous administration for 5 days and investigated the potential mechanisms underlying such activities. In vivo, DDKA significantly reduced thrombus weight in the model of arterio-venous shunt. Meanwhile, DDKA increased plasma cAMP level determined by radioimmunoassay in the same model. Notably, DDKA prolonged PT and APTT in rats after intravenous administration DDKA for successive 5 days. In vitro, pretreatment with DDKA on washed rat platelets significantly inhibited various agonists stimulated platelet aggregation and caused an increase in cAMP level in platelets activated by ADP. These findings support our hypothesis that DDKA possesses antiplatelet and antithrombotic activities. The mechanisms underlying such activities may involve the anticoagulatory effect and cAMP induction. 相似文献
917.
The onset and distribution of the calcium binding proteins, calretinin, calbindin, and parvalbumin, were examined in the optic tectum of Alligator mississipiensis embryos between Stages 18 and 26–28. The immunoreactivity of each calcium binding protein correlated well with the results from the Western blot experiments. In terms of onset and distribution, calretinin expressison was the most widespread of the three calcium binding proteins that were examined, and was also the earliest to be visualized. Calbindin expression occurred next, whereas parvalbumin expression was the most limited and appeared last. For small calretinin (+) neurons, the pattern of immunoreactivity during development was from inside to outside, whereas for the larger cells, it was from outside to inside. For calbindin immunoreactive cells in the superficial zone, the pattern was from outside to inside. The distribution of the parvalbumin immunopositive neurons did not change significantly over the time period examined. Similar data on other amniotes is limited. However, the pattern in Alligator shares some similarities with kittens in regards to the distribution of calbindin and parvalbumin in the developing superior colliculus. © 2013 Wiley Periodicals, Inc. Develop Neurobiol 73: 899–910, 2013 相似文献
918.
Peng Zhenying Ruan Jian Tian Haiying Shan Lei Meng Jingjing Guo Feng Zhang Zhimeng Ding Hong Wan Shubo Li Xinguo 《Plant Molecular Biology Reporter》2020,38(2):209-221
Plant Molecular Biology Reporter - The synthesis of α-linolenic acid (ALA) requires the activity of ω-3 fatty acid desaturases (ω-3 FADs). The quality of peanut oil would be much... 相似文献
919.
do Espírito Santo Elaine Patrícia Tavares Monteiro Ruan Campos da Costa Ana Roberta Fusco Marques-da-Silva Silvia Helena 《Mycopathologia》2020,185(2):307-317
Mycopathologia - Recently, Trichosporon taxonomy has been reevaluated and new genera of the Trichosporonaceae family have been described. Here, 26 clinical isolates were submitted for... 相似文献
920.
Wu Chung-I Wen Haijun Lu Jian Su Xiao-dong Hughes Alice C. Zhai Weiwei Chen Chen Chen Hua Li Mingkun Song Shuhui Qian Zhaohui Wang Qihui Chen Bingjie Guo Zixiao Ruan Yongsen Lu Xuemei Wei Fuwen Jin Li Kang Le Xue Yongbiao Zhao Guoping Zhang Ya-Ping 《中国科学:生命科学英文版》2021,64(9):1560-1563
正In the comparison with SARS-CoVof 2003, SARS-CoV-2 is extremely well adapted to the human populations and its adaptive shift from the animal host to humans must have been even more extensive. By the blind watchmaker argument, such an adaptive shift can only happen prior to the onset of the current pandemic and with the aid of step-by-step selection. 相似文献