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Yamamoto K Choi M Abe D Shimizu M Yamada S 《The Journal of steroid biochemistry and molecular biology》2007,103(3-5):282-285
We achieved exhaustive alanine scanning mutational analysis of the amino acid residues lining the ligand binding pocket of the Vitamin D receptor to investigate the mechanism of the ligand recognition by the receptor. This is the first exhaustive analysis in the nuclear receptor superfamily. Our results demonstrated the role and importance of all the residues lining the ligand binding pocket. In addition, this analysis was found to indicate ligand-specific ligand-protein interactions, which have key importance in determining the transactivation potency of the individual ligands. Thus, the analysis using 1beta-methyl-1alpha,25-dihydroxyvitamin D(3) revealed the specific van der Waals interactions of 1beta-methyl group with the receptor. 相似文献
164.
Aeryun Kim Stephanie L. Servetas Jieun Kang Jinmoon Kim Sungil Jang Yun Hui Choi Hanfu Su Yeong-Eui Jeon Youngmin A. Hong Yun-Jung Yoo D. Scott Merrell Jeong-Heon Cha 《Journal of microbiology (Seoul, Korea)》2016,54(12):846-852
The array of outer membrane proteins (OMPs) found in Helicobacter pylori provides a crucial component for persistent colonization within the gastric niche. Not only does H. pylori harbor a wide number of OMPs, but these OMPs often vary across strains; this likely contributes to immune evasion, adaptation during long term colonization, and potentially differential disease progression. Previous work from our group described OMP differences among the Bab family (babA, babB, and babC) and Hom family (homA and homB) from 80 American H. pylori clinical isolates (AH) and 80 South Korean H. pylori clinical isolates (KH). In the current study, we expanded our investigation to include the less well characterized Hom family member, HomC. 相似文献
165.
Hye Jeong Lee Na Young Choi Seung-Won Lee Kisung Ko Tae Sook Hwang Dong Wook Han 《Epigenetics》2016,11(3):177-183
Spermatogonial stem cells (SSCs), which are unipotent stem cells in the testes that give rise to sperm, can be converted into germline-derived pluripotent stem (gPS) by self-induction. The androgenetic imprinting pattern of SSCs is maintained even after their reprogramming into gPS cells. In this study, we used an in vitro neural differentiation model to investigate whether the imprinting patterns are maintained or altered during differentiation. The androgenetic patterns of H19, Snrpn, and Mest were maintained even after differentiation of gPS cells into NSCs (gPS-NSCs), whereas the fully unmethylated status of Ndn in SSCs was altered to somatic patterns in gPS cells and gPS-NSCs. Thus, our study demonstrates epigenetic alteration of genomic imprinting during the induction of pluripotency in SSCs and neural differentiation, suggesting that gPS-NSCs can be a useful model to study the roles of imprinted genes in brain development and human neurodevelopmental disorders. 相似文献
166.
Geon Ha Kim Seun Jeon Kiho Im Hunki Kwon Byung Hwa Lee Ga Young Kim Hana Jeong Noh Eul Han Sang Won Seo Hanna Cho Young Noh Sang Eon Park Hojeong Kim Jung Won Hwang Cindy W. Yoon Hee Jin Kim Byoung Seok Ye Ju Hee Chin Jung-Hyun Kim Mee Kyung Suh Jong Min Lee Sung Tae Kim Mun-Taek Choi Mun Sang Kim Kenneth M Heilman Jee Hyang Jeong Duk L. Na 《PloS one》2015,10(4)
The purpose of this study was to investigate if multi-domain cognitive training, especially robot-assisted training, alters cortical thickness in the brains of elderly participants. A controlled trial was conducted with 85 volunteers without cognitive impairment who were 60 years old or older. Participants were first randomized into two groups. One group consisted of 48 participants who would receive cognitive training and 37 who would not receive training. The cognitive training group was randomly divided into two groups, 24 who received traditional cognitive training and 24 who received robot-assisted cognitive training. The training for both groups consisted of daily 90-min-session, five days a week for a total of 12 weeks. The primary outcome was the changes in cortical thickness. When compared to the control group, both groups who underwent cognitive training demonstrated attenuation of age related cortical thinning in the frontotemporal association cortices. When the robot and the traditional interventions were directly compared, the robot group showed less cortical thinning in the anterior cingulate cortices. Our results suggest that cognitive training can mitigate age-associated structural brain changes in the elderly.
Trial Registration
ClnicalTrials.gov NCT01596205 相似文献167.
168.
Using Escherichia coli cell-free protein synthesis system and aminoacylated amber suppressor tRNA, we successfully inserted an unnatural amino acid S-(2-nitrobenzyl)cysteine into human erythropoietin. Three different types of translation stop suppression were observed and each of the three types was easily discerned with SDS-PAGE. Optimal conditions were established for correct stop and programmed suppressions. Since this system differentiates proteins produced by misreading of codons from those produced by programmed suppression, we conclude that this cell-free translation system that we describe in this paper will be of a great use for future investigations on translation stop processes. 相似文献
169.