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991.
992.
993.
Minji Lee Yeonhwa Song Inhee Choi Su-Yeon Lee Sanghwa Kim Se-Hyuk Kim Jiho Kim Haeng Ran Seo 《Molecules and cells》2021,44(1):50
Among all cancer types, lung cancer ranks highest worldwide in terms of both incidence and mortality. The crosstalk between lung cancer cells and their tumor microenvironment (TME) has begun to emerge as the “Achilles heel” of the disease and thus constitutes an attractive target for anticancer therapy. We previously revealed that crosstalk between lung cancer cells and endothelial cells (ECs) induces chemoresistance in multicellular tumor spheroids (MCTSs). In this study, we demonstrated that factors secreted in response to crosstalk between ECs and lung cancer cells play pivotal roles in the development of chemoresistance in lung cancer spheroids. We subsequently determined that the expression of hypoxia up-regulated protein 1 (HYOU1) in lung cancer spheroids was increased by factors secreted in response to crosstalk between ECs and lung cancer cells. Direct interaction between lung cancer cells and ECs also caused an elevation in the expression of HYOU1 in MCTSs. Inhibition of HYOU1 expression not only suppressed stemness and malignancy, but also facilitated apoptosis and chemosensitivity in lung cancer MCTSs. Inhibition of HYOU1 expression also significantly increased the expression of interferon signaling components in lung cancer cells. Moreover, the activation of the PI3K/AKT/mTOR pathway was involved in the HYOU1-induced aggression of lung cancer cells. Taken together, our results identify HYOU1, which is induced in response to crosstalk between ECs and lung cancer cells within the TME, as a potential therapeutic target for combating the aggressive behavior of cancer cells. 相似文献
994.
995.
Cho HY Seo MJ Park JU Kang BW Kim GY Joo WH Lee YC Cho YS Jeong YK 《Journal of microbiology (Seoul, Korea)》2011,49(6):1018-1021
A fibrinolytic enzyme was found in a Gram-negative bacterium, Aeromonas sp. JH1. SDS-PAGE and fibrinzymography showed that it was a 36 kDa, monomeric protein. Of note, the enzyme was highly specific
for fibrinogen molecules and the hydrolysis rate of fibrinogen subunits was highest for α, β, and γ chains in that order.
The first 15 amino acids of N-terminal sequence were X-D-A-T-G-P-G-G-N-V-X-T-G-K-Y, which was distinguishable from other fibrinolytic
enzymes. The optimum pH and temperature of the enzyme were approximately 8.0 and 40°C, respectively. Therefore, these results
provide a fibrinolytic enzyme with potent thrombolytic activity from the Aeromonas genus. 相似文献
996.
Youn-Ho Shin Young-Kwon Seo Hee-Hoon Yoon Bo-Young Yoo Kye-Yong Song Jung-Keug Park 《Biotechnology and Bioprocess Engineering》2011,16(4):793-800
The adult hair follicle has well-defined dermal and epithelial populations that display distinct developmental properties.
The follicular dermal cells, namely the dermal papilla and dermal sheath, are derived from the same mesenchymal cells as dermal
fibroblasts and therefore, we believed that follicular cells could be useful sources of interfollicular keratinocytes and
fibroblast for skin wound repair. In this study, we evaluated the relative effect of various mesenchymal-derived cells on
wound healing following skin injury. Human dermal cells, including two different follicular dermal cells and skin fibroblasts
were cultured in collagen sponges and compared with respect to wound healing. Results indicated that there was no significant
difference in wound contraction and angiogenesis among the cell types. Further, dermal sheath cells exhibited relatively poor
results compared with other cells in new collagen synthesis. Finally, basement membrane reformation and new collagen synthesis
for the dermal papilla cell grafts was superior to those of the dermal sheath cells or fibroblasts. 相似文献
997.
998.
In this study, we demonstrated the asymmetric synthesis of L-tert-leucine from trimethylpyruvate using branchedchain aminotransferase (BCAT) from Escherichia coli in the presence of L-glutamate as an amino donor. Since BCAT was severely inhibited by 2-ketoglutarate, in order to overcome this here, we developed a BCAT/aspartate aminotransferase (AspAT) and BCAT/AspAT/pyruvate decarboxylase (PDC) coupling reaction. In the BCAT/ AspAT/PDC coupling reaction, 89.2 mM L-tert-leucine (ee >99%) was asymmetrically synthesized from 100 mM trimethylpyruvate. 相似文献
999.
Optimal conditions for a high cell density fermentation were investigated in a recombinant Escherichia coli producing salmosin, a platelet aggregation inhibitor. The optimized carbon and nitrogen sources were glycerol 10 g/l, yeast extract 30 g/l, and bacto-tryptone 10 g/l, yielding the dry cell weight (DCW) of 10.61 g/l in a 500 ml flask culture. The late-stage induction with 1% L-arabinose in a 5 l jar fermentor showed the highest DCW of 65.70 g/l after 27 h of the fed-batch fermentation. Around 2,200 mg/l of the protein was expressed as an inclusion body that was then refolded to obtain the active salmosin of 96 mg/l. We also confirmed the inhibitory activity against platelet aggregation of the active salmosin from the high cell density fermentation. 相似文献
1000.
Hertwig’s epithelial root sheath/Epithelial rests of Malassez (HERS/ERM) cells are unique epithelial cells in the periodontal
ligament. They remain in periodontal tissues through-out the adult life, and it is expected that their functional role is
to maintain the homeostasis of the periodontium through reciprocal interactions with other periodontal cells. In this study,
we investigated whether HERS/ERM cells have primitive stem cell characteristics: those of embryonic stem cells as well as
of epithelial stem cells. Primary HERS/ERM cells had typical epithelial cell morphology and characteristics and they maintained
for more than five passages. They expressed epithelial stem cell-related genes: ABCG2, ANp63, p75, EpCAM, and Bmi-1. Moreover,
the expression of embryonic stem cell markers such as Oct-4, Nanog, and SSEA-4 were detected. Next, we investigated whether
the expression of these stem cell markers was maintained during the sub-culture process. HERS/ERM cells showed different expression
levels of these stemness genes at each passage, but their expression was maintained throughout the passages. Taken together,
our data suggest that a primary culture of HERS/ERM cells contains a population of primitive stem cells that express epithelial
stem cell markers and embryonic stem cell markers. Furthermore, these cell populations were maintained during the sub-culturing
process in our culture conditions. Therefore, our findings suggest that there is a strong possibility of accomplishing cementum
tissue engineering with HERS/ERM cells. 相似文献