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排序方式: 共有218条查询结果,搜索用时 234 毫秒
71.
Ho-Joon Lee Jiwon Ahn Cho-Rock Jung Yun-Ji Jeung Hyun-Soo Cho Myung Jin Son Kyung-Sook Chung 《Biotechnology and bioengineering》2020,117(6):1864-1876
Although primary human hepatocytes (PHHs) are the gold standard in drug efficacy and metabolism studies, long-term survival of PHHs and maintenance of their hepatic function are still challenging. In this study, we focused on the effect of the initial microenvironment on upregulation and long-term preservation of hepatic function of PHHs encapsulated within biodegradable hydrogel systems. PHHs were encapsulated in RGD-functionalized hybrid hydrogels with various degrees of degradability, and their hepatic functionality was analyzed. Regardless of the hydrogel elastic modulus, the combination with nondegradable hydrogels had a predominantly negative effect on the prompt engraftment of PHHs, whereas a degradable hydrogel with intermediate initial degradability was most effective in maintaining hepatic function. Efficient network formation by PHHs and cocultured cells, along with the control of hydrogel degradation, governed the hepatic functionality at an early stage and upon long-term cultivation. Under optimized conditions, expression of genes involved in biological processes such as focal adhesions, cell survival, cytoskeleton formation, and extracellular matrix interactions was significantly higher than that in a control with relatively delayed initial degradation. Thus, we suggest that the orchestrated control of initial cellular remodeling may play an important role in the maintenance of hepatic function in a three-dimensional PHH culture. 相似文献
72.
To design artificial restriction enzymes, synthetic catalytic centers that effectively hydrolyze linear double-stranded polydeoxyribonucleotides are needed. The Co(III) complex of cyclen (CoCyc) attached to polystyrene derivatives hydrolyzes linearized pUC18 DNA with half-lives as short as 30 min at 25 degrees C. The catalytic activity of CoCyc is enhanced by >150 times on attachment to the resin. 相似文献
73.
David-Marian Otte Maria Luisa Barcena de Arellano Andras Bilkei-Gorzo ?nder Albayram Sophie Imbeault Haang Jeung Judith Alferink Andreas Zimmer 《PloS one》2013,8(6)
NMDA receptors are activated after binding of the agonist glutamate to the NR2 subunit along with a co-agonist, either L-glycine or D-serine, to the NR1 subunit. There is substantial evidence to suggest that D-serine is the most relevant co-agonist in forebrain regions and that alterations in D-serine levels contribute to psychiatric disorders. D-serine is produced through isomerization of L-serine by serine racemase (Srr), either in neurons or in astrocytes. It is released by astrocytes by an activity-dependent mechanism involving secretory vesicles. In the present study we generated transgenic mice (SrrTg) expressing serine racemase under a human GFAP promoter. These mice were biochemically and behaviorally analyzed using paradigms of anxiety, depression and cognition. Furthermore, we investigated the behavioral effects of long-term administration of D-serine added to the drinking water. Elevated brain D-serine levels in SrrTg mice resulted in specific behavioral phenotypes in the forced swim, novelty suppression of feeding and olfactory bulbectomy paradigms that are indicative of a reduced proneness towards depression-related behavior. Chronic dietary D-serine supplement mimics the depression-related behavioral phenotype observed in SrrTg mice. Our results suggest that D-serine supplementation may improve mood disorders. 相似文献
74.
Tae Sik Goh Jung Sub Lee Jeung Il Kim Yong Geon Park Kyoungjune Pak Dae Cheon Jeong Sae-Ock Oh Yun Hak Kim 《Journal of cellular physiology》2019,234(8):13851-13857
With the recent emphasis on the importance of personalized genomic medicine, studies have performed prognostic stratification using gene signatures in cancers. However, these studies have not considered gene networks with clinical data. Therefore, this study aimed to develop a novel prognostic score using grouped variable selection for patients with osteosarcoma. We assessed messenger RNA (mRNA) expression and clinical data from Gene Expression Omnibus to develop a novel prognostic scoring system for patients with osteosarcoma. Variable selection using Network-Regularized high-dimensional Cox-regression analysis with information regarding gene networks obtained from six large pathway databases was performed. We determined the risk score on the linear combination of regression coefficients and mRNA expression values. Log-rank test, UNO's c-index, and area under the curve (AUC) values were determined to evaluate the discriminatory power between the low- and high-risk groups. A recently reported next-generation Connectivity Map was used to identify future therapeutic targets for osteosarcoma. Our novel model had significantly high discriminatory power in predicting overall survival. An optimal c-index of 0.967 was obtained and time-dependent receiver operating characteristic analysis revealed an acceptable predictive value of AUC between 0.953 and 1.000. Knockdown of BACE2 or ING2 and linifanib treatment may improve the prognosis of patients with osteosarcoma. Herein, this novel prognostic scoring system would not only facilitate a more accurate prediction of patient prognosis, but also contribute to the selection of suitable therapeutic alternatives for osteosarcoma patients. 相似文献
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78.
Yun Hee Baek Jeung Hyun Park Young Jun Song Min-Suk Song Philippe Noriel Q. Pascua Yoon-Soo Hahn Heon-Seok Han Ok-Jun Lee Ki-Soon Kim Chun Kang Young-Ki Choi 《Journal of microbiology (Seoul, Korea)》2009,47(1):91-100
To investigate the genetic characteristics of human influenza viruses circulating in Chungbuk province, we tested 510 clinical
samples of nasopharyngeal suction from pediatric patients diagnosed with respiratory illness between June 2007 and June 2008.
Genetic characterization of the HA genes of H3N2 isolates indicated the relative higher similarity to A/Virginia/04/07 (99.6%)
rather than that of A/Wisconsin/67/2005 (98.4%), a Northern Hemisphere 2007∼2008 vaccine strain, based on amino acid sequences.
We found several altered amino acids at the H3 HA1 antigenic sites compared with the vaccine strain; K140I at site A, K158R
at site B, and K173N (H471) or K173Q, and S262N at site E, but there was no antigenic shift among the H3N2 viruses. Interestingly,
A/Cheongju/H383/08 and A/Cheongju/H407/08 isolates had single amino acid substitution at D151G on the catalytic site of the
N2 NA while A/Cheongju/H412/08 and A/Cheongju/ H398/07 isolates had one amino acid deletion at residue 146. Furthermore, we
found that 25% (3 out of 12 isolates) of the H3N2 subtype viruses had the amino acid substitution at position 31 on the M2
protein (Aspartic acid to Asparagine) and confirmed their drug-resistance by biological assays. Taken together, the results
of this study demonstrated continuous evolutions of human H3N2 viruses by antigenic drift and also highlighted the need to
closely monitor antigenic drug resistance in influenza A viruses to aid in the early detection of potentially pandemic strains,
as well as underscore the need for new therapeutics. 相似文献
79.
Bo-Mi Lee Geun-Shik Lee Eui-Man Jung Kyung-Chul Choi Eui-Bae Jeung 《Reproductive biology and endocrinology : RB&E》2009,7(1):49
Transient receptor potential cation channel, subfamily V, member 6 (TRPV6) is an epithelial Ca2+ channel protein expressed in calcium absorbing organs. In the present study, we investigated the expression and regulation
of uterine and placental TRPV6 during gestation in rodents. Uterine TRPV6 peaked at pregnancy day (P) 0.5, P5.5 and, P13.5
and was detected in uterine epithelium and glands of rats, while placental TRPV6 mRNA levels increased in mid-gestation. Uterine
and placental TRPV6 mRNA levels in rats appear to cyclically change during pregnancy, suggesting that TRPV6 may participate
in the implantation process. In addition, uterine TRPV6 mRNA is only expressed in placenta-unattached areas of the uterus,
and uterine TRPV6 immunoreactivity was observed in luminal and glandular epithelial cells. In the placenta, TRPV6 was detected
in the labyrinth and spongy zone. These results may indicate that TRPV6 has at least two functions: implantation of the embryo
and maintenance of pregnancy. To investigate the pathway(s) mediating TRPV6 expression in rodents, anti-steroid hormone antagonists
were injected prior to maximal TRPV6 expression. In rats, TRPV6 expression was reduced by RU486 (an anti-progesterone) through
progesterone receptors, and ICI 182,780 (an anti-estrogen) blocked TRPV6 expression via estrogen receptors in mice. The juxtaposition
of uterine and placental TRPV6 expressed in these tissues supports the notion that TRPV6 participates in transferring calcium
ions between the maternal and fetal compartments. Taken together, TRPV6 gene may function as a key element in controlling
calcium transport in the uterus between the embryo and the placenta during pregnancy. 相似文献
80.
Ying-Chao Lin Ai-Ru Hsieh Ching-Lin Hsiao Shang-Jung Wu Hui-Min Wang Ie-Bin Lian Cathy SJ Fann 《Journal of biomedical science》2014,21(1)