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51.
Jeon MS Yi TG Lim HJ Moon SH Lee MH Kang JS Kim CS Lee DH Song SU 《World journal of stem cells》2011,3(8):70-82
AIM:To characterize single-cell-derived mouse clonal mesenchymal stem cells (mcMSCs) established with bone marrow samples from three different mouse strains. METHODS:We established mcMSC lines using subfractionation culturing method from bone marrow samples obtained from long bones.These lines were characterized by measuring cell growth, cell surface epitopes, differentiation potential, lineage-specific gene expression and T-cell suppression capability. Nonclonal MSCs isolated by the conventional gradient centrifugation method were used as controls. RESULTS:All mcMSC lines showed typical nonclonal MSC-like spindle shape morphology. Lines differed inoptimal growth density requirement.Cell surface epitope prof iles of these mcMSC lines were similar to those of nonclonal MSCs. However, some lines exhibited different expression levels in a few epitopes, such as CD44 and CD105. Differentiation assays showed that 90% of the mcMSC lines were capable of differentiating into adipogenic and/or chondrogenic lineages, but only 20% showed osteogenic lineage differentiation. T-cell suppression analysis showed that 75% of the lines exhibited T-cell suppression capability. CONCLUSION:mcMSC lines have similar cell morphology and cell growth rate but exhibit variations in their cell surface epitopes, differentiation potential, lineage-specifi c gene expression and T-cell suppression capability. 相似文献
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Joong Kyun Kim Eugene L. Iannotti Rakesh Bajpai 《Biotechnology and Bioprocess Engineering》1999,4(1):1-11
Considerations of partition coefficients, selectivity, biocompatibility, and waste generation are important in selection of
appropriate solvents to be used for extractive recovery of products from fermentation broths. Several selection criteria can
be used based upon the nature of different species present in the broth. These criteria, along with examples of specific case
studies, were presented. These serve not only in screening of useful solvents, but also in pointing to the specific modes
of operation of recovery-coupled bioprocesses. 相似文献
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Hierarchical Zn–Co–S Nanowires as Advanced Electrodes for All Solid State Asymmetric Supercapacitors 下载免费PDF全文
A facile two‐step strategy is developed to design the large‐scale synthesis of hierarchical, unique porous architecture of ternary metal hydroxide nanowires grown on porous 3D Ni foam and subsequent effective sulfurization. The hierarchical Zn–Co–S nanowires (NWs) arrays are directly employed as an electrode for supercapacitors application. The as‐synthesized Zn–Co–S NWs deliver an ultrahigh areal capacity of 0.9 mA h cm?2 (specific capacity of 366.7 mA h g?1) at a current density of 3 mA cm?2, with an exceptional rate capability (≈227.6 mA h g?1 at a very high current density of 40 mA cm?2) and outstanding cycling stability (≈93.2% of capacity retention after 10 000 cycles). Most significantly, the assembled Zn–Co–S NWs//Fe2O3@reduced graphene oxide asymmetric supercapacitors with a wide operating potential window of ≈1.6 V yield an ultrahigh volumetric capacity of ≈1.98 mA h cm?3 at a current density of 3 mA cm?2, excellent energy density of ≈81.6 W h kg?1 at a power density of ≈559.2 W kg?1, and exceptional cycling performance (≈92.1% of capacity retention after 10 000 cycles). This general strategy provides an alternative to design the other ternary metal sulfides, making it facile, free‐standing, binder‐free, and cost‐effective ternary metal sulfide‐based electrodes for large‐scale applications in modern electronics. 相似文献
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Won Yong Jung Haneul Kim Se Jin Jeon Hye Jin Park Hyuck Jai Choi Nam Jae Kim Dong Hyun Kim Dae Sik Jang Jong Hoon Ryu 《Neurochemical research》2018,43(2):351-362
Eclalbasaponin II derived from Eclipta prostrata L. (Asteraceae) has been reported to have anti-fibrotic, anti-bacterial and autophagic activities, but its effect on cognitive function has not been investigated. We studied the effect of eclalbasaponin II on cholinergic blockade-induced memory impairment in mice using the passive avoidance, Y-maze, and Morris water maze tasks. Eclalbasaponin II (10 or 20 mg/kg, p.o.) significantly ameliorated the cognitive dysfunction induced by scopolamine in the passive avoidance, Y-maze, and the Morris water maze tasks. To identify the mechanism of the memory-ameliorating effect of eclalbasaponin II, acetylcholinesterase (AChE) activity assay, Western blot analysis and electrophysiology were conducted. Eclalbasaponin II inhibited the AChE activity in ex vivo study, and the administration of eclalbasaponin II and its metabolite, echinocystic acid, increased the phosphorylation levels of memory-related signaling molecules, including protein kinase B (Akt) and glycogen synthase kinase-3β (GSK-3β), in the hippocampus. Although eclalbasaponin II did not affect hippocampal long term potentiation (LTP), echinocystic acid significantly enhanced hippocampal LTP formation (30 μM). These results suggest that eclalbasaponin II ameliorates cholinergic blockade-induced cognitive impairment via AChE inhibition, LTP formation and the activation of Akt-GSK-3β signaling, and that eclalbasaponin II may be a useful to treat cognitive impairment derived from cholinergic dysfunction. 相似文献
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Jungil Yang Lae‐Hyeon Cho Jinmi Yoon Hyeryung Yoon Antt Htet Wai Woo‐Jong Hong Muho Han Hitoshi Sakakibara Wanqi Liang Ki‐Hong Jung Jong‐Seong Jeon Hee‐Jong Koh Dabing Zhang Gynheung An 《Plant biotechnology journal》2019,17(1):178-187
Grain number is an important agronomic trait. We investigated the roles of chromatin interacting factor Oryza sativa VIN3‐LIKE 2 (OsVIL2), which controls plant biomass and yield in rice. Mutations in OsVIL2 led to shorter plants and fewer grains whereas its overexpression (OX) enhanced biomass production and grain numbers when compared with the wild type. RNA‐sequencing analyses revealed that 1958 genes were up‐regulated and 2096 genes were down‐regulated in the region of active division within the first internodes of OX plants. Chromatin immunoprecipitation analysis showed that, among the downregulated genes, OsVIL2 was directly associated with chromatins in the promoter region of CYTOKININ OXIDASE/DEHYDROGENASE2 (OsCKX2), a gene responsible for cytokinin degradation. Likewise, active cytokinin levels were increased in the OX plants. We conclude that OsVIL2 improves the production of biomass and grain by suppressing OsCKX2 chromatin. 相似文献
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