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991.
992.
Zhang Xiaonan Lu Yufang Yang Ting Kronzucker Herbert J. Shi Weiming 《Plant and Soil》2019,441(1-2):253-259
Plant and Soil - Depending on the availability and stoichiometry of nutrients in soil, microbes and plants can compete for the same resources. In this study we aimed to test how microbial nutrient... 相似文献
993.
994.
Sihua Liu Hongyun Liu Keke Zhang Xueping Li Yuqin Duan Zhiyun Wang Tao Wang 《中国病毒学》2019,34(5):572-582
Severe fever with thrombocytopenia syndrome(SFTS) is an emerging hemorrhagic fever disease caused by SFTSV, a newly discovered phlebovirus that is named after the disease. Currently, no effective vaccines or drugs are available for use against SFTSV infection, as our understanding of the viral pathogenesis is limited. Bortezomib(PS-341), a dipeptideboronic acid analog, is the first clinically approved proteasome inhibitor for use in humans. In this study, the antiviral efficacy of PS-341 against SFTSV infection was tested in human embryonic kidney HEK293 T(293 T) cells. We employed four different assays to analyze the antiviral ability of PS-341 and determined that PS-341 inhibited the proliferation of SFTSV in 293 T cells under various treatment conditions. Although PS-341 did not affect the virus absorption, PS-341 treatment within a non-toxic concentration range resulted in a significant reduction of progeny viral titers in infected cells.Dual-luciferase reporter assays and Western blot analysis revealed that PS-341 could reverse the SFTSV-encoded nonstructural protein(NS) mediated degradation of retinoic acid-inducible gene-1(RIG-I), thereby antagonizing the inhibitory effect of NSs on interferons and blocking virus replication. In addition, we observed that inhibition of apoptosis promotes virus replication. These results indicate that targeting of cellular interferon pathways and apoptosis during acute infection might serve as the bases of future therapeutics for the treatment of SFTSV infections. 相似文献
996.
997.
Kyaw Lin Maung Dapeng Jing Tiantao Zhang Sivaprasath Prabu Kanglai He Shuxiong Bai Zhenying Wang 《Journal of Asia》2021,24(1):7-14
Niemann-Pick type C2 (NPC2) proteins in arthropods have been extensively differentiated and possibly duplicated according to environmental conditions and are probable to have different functions. The participation of NPC2 proteins in chemical communication in arthropods brings new objectives in environmental-friendly strategies for pest population control. In this study, NPC2 gene in Macrocentrus cingulum (McinNPC2) was newly identified by rapid amplification cDNA ends (RACE) technology. McinNPC2 amino acid sequence alignment with other representative NPC2 annotates to evaluate the highly conserved consensus amino acids, but with odorant binding proteins in M. cingulum show that only one consensus amino acid. Primary six-cysteine structures that are same to odorant binding proteins in M. cingulum were observed in McinNPC2. Phylogenetic analysis of McinNPC2 indicated that the nearest monophyletic group forming one clade with high posterior probability values clusters as Cyphomyrmex costatus (CcosNPC2) whereas the nearest evolutionary relation group as some odorant binding proteins. Moreover, quantitative real-time PCR (qPCR) measurements show that the McinNPC2 gene expression level in various tissues of the female is significantly and ubiquitously higher than in male, whereas the highest expression level in female antennae. We further explore the binding characterization of recombinant McinNPC2 to candidate odor molecules and did the modeling and docking simulations. The results showed ligands binding specificity and docking tests results indicate that β-ionone, an aroma compound commonly found in essential oils, can strongly bind with McinNPC2. In conclusion, we proposed that McinNPC2 may be involved in chemical communication and play roles in perception of plant volatiles. 相似文献
998.
Yang Bo Ao Yawen Liu Ying Zhang Xuefen Li Ying Tang Fengru Xu Haibo 《Neurochemical research》2021,46(6):1487-1501
Neurochemical Research - Activation of dopamine (DA) neurons is essential for the transition from sleep to wakefulness and maintenance of awakening, and sufficient to accelerate the emergence from... 相似文献
999.
Xia Wang Yan Li Winnie Deuther-Conrad Fang Xie Xin Chen Meng-Chao Cui Xiao-Jun Zhang Jin-Ming Zhang Jörg Steinbach Peter Brust Bo-Li Liu Hong-Mei Jia 《Bioorganic & medicinal chemistry》2013,21(1):215-222
We report the synthesis and evaluation of a series of fluoro-oligo-ethoxylated 4-benzylpiperazine derivatives as potential σ1 receptor ligands. In vitro competition binding assays showed that 1-(1,3-benzodioxol-5-ylmethyl)-4-(4-(2-fluoroethoxy)benzyl)piperazine (6) exhibits low nanomolar affinity for σ1 receptors (Ki = 1.85 ± 1.59 nM) and high subtype selectivity (σ2 receptor: Ki = 291 ± 111 nM; Kiσ2/Kiσ1 = 157). [18F]6 was prepared in 30–50% isolated radiochemical yield, with radiochemical purity of >99% by HPLC analysis after purification, via nucleophilic 18F? substitution of the corresponding tosylate precursor. The log DpH 7.4 value of [18F]6 was found to be 2.57 ± 0.10, which is within the range expected to give high brain uptake. Biodistribution studies in mice demonstrated relatively high concentration of radiotracers in organs known to contain σ1 receptors, including the brain, lungs, kidneys, heart, and spleen. Administration of haloperidol 5 min prior to injection of [18F]6 significantly reduced the concentration of radiotracers in the above-mentioned organs. The accumulation of radiotracers in the bone was quite low suggesting that [18F]6 is relatively stable to in vivo defluorination. The ex vivo autoradiography in rat brain showed high accumulation of radiotracers in the brain areas known to possess high expression of σ1 receptors. These findings suggest that [18F]6 is a suitable radiotracer for imaging σ1 receptors with PET in vivo. 相似文献
1000.
Xiong Zhang Ming-You Peng En-Ming Feng Qing-Dan Li Lu Chen Hu-Cheng Yang Bing Guo Hong Liang Ying-Tong Di Lei Tang Ying Yan 《化学与生物多样性》2023,20(10):e202301061
Three previously undescribed diterpenoids, helioscopnoids A–C, and eight known compounds were isolated from the whole plants of Euphorbia helioscopia. Their structures were established by extensive analysis of spectra and data comparison with previous literatures. Among them, compound 4 was identified as 24,24-dimethoxy-25,26,27-trinoreuphan-3β-ol with revised configurations of C-13, C-14, and C-17 (13R*, 14R*, 17R*). Cytotoxicity assays revealed that all compounds exhibited varying levels of cytotoxicity against H1975 cells, with compound 9 displaying the most potent activity, as indicated by cell viability rates of 18.13 % and 20.76 % at concentrations of 20 μM and 5 μM, respectively. This study expands the understanding of E. helioscopia terpenoids’ structural diversity and biological activities, contributing to the exploration of potential therapeutic applications. 相似文献