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101.
102.
1 引言 柳牡蛎蚧(Lepidosaphes salicina Bersch)(同翅目:盾蚧科)是一种以为害杨树为主的刺吸式害虫之一,广泛分布于“三北”防护林区,该蚧一年发生一代,以卵越冬。通过刺吸式口器刺入树皮内,吸取树木养分和水分,并使树木表皮栓化。同时,由于枝干被蚧壳所覆盖,对呼吸及光合作用也有影响,特别是幼树被害后,一般 相似文献
103.
Jia Chen Min Zhao Hongjuan Zhou Yiyuan Tang Wei Ji Jianhua Shao Chunjie Zhao Chunchao Zhao 《化学与生物多样性》2023,20(4):e202300246
Viburnum luzonicum is widely distributed in China. Its branch extracts showed potential α-amylase and α-glucosidase inhibitory activities. In order to discover new bioactive constituents, five undescribed phenolic glycosides, viburozosides A−E ( 1 – 5 ), were obtained by bioassay-guided isolation coupled with HPLC-QTOF-MS/MS analysis. Their structures were elucidated by spectroscopic analyses, including 1D NMR, 2D NMR, ECD, and ORD. All compounds were tested for their α-amylase and α-glucosidase inhibitory potency. Compound 1 showed significantly competitive inhibition against α-amylase (IC50=17.5 μM) and α-glucosidase (IC50=13.6 μM). 相似文献
104.
Xuebing Xu Tong Wu Renjie Lin Shengze Zhu Jie Ji Dandan Jin Mengxiang Huang Wenjie Zheng Wenkai Ni Feng Jiang Shihai Xuan Mingbing Xiao 《Journal of cellular and molecular medicine》2023,27(23):3672-3680
The migrasome is a new organelle discovered by Professor Yu Li in 2015. When cells migrate, the membranous organelles that appear at the end of the retraction fibres are migrasomes. With the migration of cells, the retraction fibres which connect migrasomes and cells finally break. The migrasomes detach from the cell and are released into the extracellular space or directly absorbed by the recipient cell. The cytoplasmic contents are first transported to the migrasome and then released from the cell through the migrasome. This release mechanism, which depends on cell migration, is named ‘migracytosis’. The main components of the migrasome are extracellular vesicles after they leave the cell, which are easy to remind people of the current hot topic of exosomes. Exosomes are extracellular vesicles wrapped by the lipid bimolecular layer. With extensive research, exosomes have solved many disease problems. This review summarizes the differences between migrasomes and exosomes in size, composition, property and function, extraction method and regulation mechanism for generation and release. At the same time, it also prospects for the current hotspot of migrasomes, hoping to provide literature support for further research on the generation and release mechanism of migrasomes and their clinical application in the future. 相似文献
105.
Doan Minh Sang Ik Ho Na Dr. Duong Tien Anh Do Thi Mai Dung Nguyen Thi Thu Hang Nguyen T. Phuong-Anh Assoc. Prof. Dr. Pham-The Hai Assoc. Prof. Dr. Dao Thi Kim Oanh Dr. Truong Thanh Tung Soo Jung Lee Joo Hee Kwon Prof. Dr. Jong Soon Kang Prof. Dr. Sang-Bae Han Assoc. Prof. Dr. Dinh Thi Thanh Hai Prof. Dr. Nguyen-Hai Nam 《化学与生物多样性》2023,20(5):e202201030
Herein, we report the design, synthesis and evaluation of novel (E)-3-(3-oxo-4-substituted-3,4-dihydro-2H-benzo[b][1,4]oxazin-6-yl)-N-hydroxypropenamides ( 4 a – i , 7 a – g ) targeting histone deacetylases. Three human cancer cell lines were used to test the cytotoxicity of the synthesized compounds (SW620, colon; PC-3, prostate; NCI−H23, lung cancer); inhibitory activity towards HDAC; anticancer activity; as well as their impact on the cell cycle and apoptosis. As a result, compounds 4 a – i bearing the alkyl substituents seemed to be less potent than the benzyl-containing compounds 7 a – g in all biological assays. Compounds 7 e – f were found to be the most active HDAC inhibitors with IC50 of 1.498±0.020 μM and 1.794±0.159 μM, respectively. In terms of cytotoxicity and anticancer assay, 7 e and 7 f also showed good activity with IC50 values in the micromolar range. In addition, the cell cycle and apoptosis of SW620 were affected by compound 7 f in almost a similar manner to that of reference compound SAHA. Docking assays were carried out for analysis the binding mode and selectivity of this compound toward 8 HDAC isoforms. Overall, our data confirmed that the inhibition of HDAC plays a pivotal role in their anticancer activity. 相似文献
106.
107.
The polyamine-derived amino acid hypusine: its post-translational formation in eIF-5A and its role in cell proliferation 总被引:1,自引:0,他引:1
Myung Hee Park Young Ae Joe Kee Ryeon Kang Young Bok Lee Edith C. Wolff 《Amino acids》1996,10(2):109-121
Summary The unusual amino acid hypusine [N
-(4-amino-2-hydroxybutyl)lysine] is a unique component of one cellular protein, eukaryotic translation initiation factor 5A (eIF-5A, old terminology, eIF-4D). It is formed posttranslationally and exclusively in this protein in two consecutive enzymatic reactions, (i) modification of a single lysine residue of the eIF-5A precursor protein by the transfer of the 4-aminobutyl moiety of the polyamine spermidine to its-amino group to form the intermediate, deoxyhypusine [N
-(4-aminobutyl)lysine] and (ii) subsequent hydroxylation of this intermediate to form hypusine. The amino acid sequences surrounding the hypusine residue are strictly conserved in all eukaryotic species examined, suggesting the fundamental importance of this amino acid throughout evolution. Hypusine is required for the activity of eIF-5Ain vitro. There is strong evidence that hypusine and eIF-5A are vital for eukaryotic cell proliferation. Inactivation of both of the eIF-5A genes is lethal in yeast and the hypusine modification appears to be a requirement for yeast survival (Schnier et al., 1991 [Mol Cell Biol 11: 3105–3114]; Wöhl et al., 1993 [Mol Gen Genet 241: 305–311]). Furthermore, inhibitors of either of the hypusine biosynthetic enzymes, deoxyhypusine synthase or deoxyhypusine hydroxylase, exert strong anti-proliferative effects in mammalian cells, including many human cancer cell lines. These inhibitors hold potential as a new class of anticancer agents, targeting one specific eukaryotic cellular reaction, hypusine biosynthesis. 相似文献
108.
Hee Wook Ryu Kyung Suk Cho Young Keun Chang Ho Nam Chang 《Biotechnology Techniques》1996,10(12):899-904
Summary
Alcaligenes eutrophus was successfully recovered from high cell density broths by pre-treatment with polyaluminium hydroxide chloride silicate as a coagulant at 36–90 mg Al/l. The optimum pH range for cell coagulation was 10–12. Subsequent centrifugation (45×g) and filtration (pore size 0.5 mm) gave a cell recovery of higher than 90%. The energy demand for cell recovery with the coagulant was only 3–11% of that without it. 相似文献
109.
Summary Double fluorescent labeling, with fluorescein isothiocyanate (FITC)-labeled F(ab)2 specific for the heavy chain and R-phycoerythrin (R-PE)-labeled F(ab)2 specific for the light chain, was demonstrated as a convenient means for the accurate evaluation of a heterogeneous non-antibody-producing population. Furthermore, it could be used for monitoring the changes in each immunoglobulin (Ig) chain content of the cells during the batch culture, which will facilitate the study on antibody synthesis, assembly and secretion. 相似文献
110.
兰科盆距兰属(Gastrochilus)植物的修订 总被引:1,自引:0,他引:1
本文对盆距兰属(Gastrochilus)植物作了修订,共分3个组,含46种和1变种,其中1个组(Sect.Caespitosi)和8个种(G.carnsus,G.garhwalensis,G.linearifolius,G.guangtungensis,G.subpapillosus,G.nanchuanensis,G.saccatusandG.gongshanensis)为新的,首次在本文作了描述报导。本属属的形态特征,研究历史和订正后属下的分类群检索表,种的文献引证、简短的特征记要和地理分布以及在属中被排除的分类单位索引均提供在本文。 相似文献