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11.
Kyoungjune Pak Yun Hak Kim Sunghwan Suh Tae Sik Goh Dae Cheon Jeong Seong Jang Kim In Joo Kim Myoung‐Eun Han Sae‐Ock Oh 《Journal of cellular and molecular medicine》2019,23(4):3010-3015
As the importance of personalized therapeutics in aggressive papillary thyroid cancer (PTC) increases, accurate risk stratification is required. To develop a novel prognostic scoring system for patients with PTC (n = 455), we used mRNA expression and clinical data from The Cancer Genome Atlas. We performed variable selection using Network‐Regularized high‐dimensional Cox‐regression with gene network from pathway databases. The risk score was calculated using a linear combination of regression coefficients and mRNA expressions. The risk score and clinical variables were assessed by several survival analyses. The risk score showed high discriminatory power for the prediction of event‐free survival as well as the presence of metastasis. In multivariate analysis, the risk score and presence of metastasis were significant risk factors among the clinical variables that were examined together. In the current study, we developed a risk scoring system that will help to identify suitable therapeutic options for PTC. 相似文献
12.
Byung Young Park Hyunghee Lee Sangee Woo Miso Yoon Jeongjun Kim Yeonhee Hong Hee Suk Lee Eun Kyu Park Jong Cheon Hahm Jin Woo Kim Soon Shik Shin Min-Young Kim Michung Yoon 《PloS one》2015,10(11)
It has been suggested that angiogenesis modulates adipogenesis and obesity. This study was undertaken to determine whether ALS-L1023 (ALS) prepared by a two-step organic solvent fractionation from Melissa leaves, which exhibits antiangiogenic activity, can regulate adipose tissue growth. The effects of ALS on angiogenesis and extracellular matrix remodeling were measured using in vitro assays. The effects of ALS on adipose tissue growth were investigated in high fat diet-induced obese mice. ALS inhibited VEGF- and bFGF-induced endothelial cell proliferation and suppressed matrix metalloproteinase (MMP) activity in vitro. Compared to obese control mice, administration of ALS to obese mice reduced body weight gain, adipose tissue mass and adipocyte size without affecting appetite. ALS treatment decreased blood vessel density and MMP activity in adipose tissues. ALS reduced the mRNA levels of angiogenic factors (VEGF-A and FGF-2) and MMPs (MMP-2 and MMP-9), whereas ALS increased the mRNA levels of angiogenic inhibitors (TSP-1, TIMP-1, and TIMP-2) in adipose tissues. The protein levels of VEGF, MMP-2 and MMP-9 were also decreased by ALS in adipose tissue. Metabolic changes in plasma lipids, liver triglycerides, and hepatic expression of fatty acid oxidation genes occurred during ALS-induced weight loss. These results suggest that ALS, which has antiangiogenic and MMP inhibitory activities, reduces adipose tissue mass in nutritionally obese mice, demonstrating that adipose tissue growth can be regulated by angiogenesis inhibitors. 相似文献
13.
14.
Lee HJ Yoon YJ Jang do S Kim C Cha HJ Hong BH Choi KY Lee HC 《Journal of biochemistry》2008,144(2):159-166
The backbone dynamics of Y14F mutant of Delta(5)-3-ketosteroid isomerase (KSI) from Comamonas testosteroni has been studied in free enzyme and its complex with a steroid analogue, 19-nortestosterone hemisuccinate (19-NTHS), by (15)N NMR relaxation measurements. Model-free analysis of the relaxation data showed that the single-point mutation induced a substantial decrease in the order parameters (S(2)) in free Y14F KSI, indicating that the backbone structures of Y14F KSI became significantly mobile by mutation, while the chemical shift analysis indicated that the structural perturbations of Y14F KSI were more profound than those of wild-type (WT) KSI upon 19-NTHS binding. In the 19-NTHS complexed Y14F KSI, however, the key active site residues including Tyr14, Asp38 and Asp99 or the regions around them remained flexible with significantly reduced S(2) values, whereas the S(2) values for many of the residues in Y14F KSI became even greater than those of WT KSI upon 19-NTHS binding. The results thus suggest that the hydrogen bond network in the active site might be disrupted by the Y14F mutation, resulting in a loss of the direct interactions between the catalytic residues and 19-NTHS. 相似文献
15.
16.
Heon Cheon Jeong Jung A. Kim Hyun Hwak Im Hyung Uk Jeong Mee Yeon Hong Jong Eun Lee Yeon Soo Han Iksoo Kim 《Biochemical genetics》2009,47(3-4):165-178
We analyzed a portion of mitochondrial COI gene sequences (658 bp) to investigate the genetic diversity and geographic variation of the swallowtail butterfly, Papilio xuthus L. (Lepidoptera: Papilionidae), and the cabbage butterfly, Pieris rapae L. (Lepidoptera: Pieridae). Papilio xuthus showed a moderate level of sequence divergence (0.91% at maximum) in 15 haplotypes, whereas Pi. rapae showed a moderate to high level of sequence divergence (1.67% at maximum) in 30 haplotypes, compared with other relevant studies. Analyses of population genetic structure showed that most populations are not genetically differentiated in both species. The distribution pattern of both species appears to be consistent with category IV of the phylogeographic pattern sensu Avise: a phylogenetic continuity, an absence of regional isolation of mtDNA clones, and extensive distribution of close clones. The observed pattern of genetic diversity and geographic variation of the two butterfly species seem to reflect the abundant habitats, abundant host plants, and flying abilities in connection with the lack of historical biogeographic barriers. 相似文献
17.
Kim HJ Yun CY Cheon HM Chae B Lee IH Park SJ Kang YJ Seo SJ 《Archives of insect biochemistry and physiology》2004,56(1):21-33
We have sequenced a cDNA clone encoding a 26-kDa ferritin subunit, which was heavy chain homologue (HCH), in fall webworm, Hyphantria cunea. The HCH cDNA was obtained from the screening of a cDNA library using a PCR product. H. cunea ferritin is composed of 221 amino acid residues and their calculated mass is 26,160 Da. The protein contains the conserved motifs for the ferroxidase center typical for heavy chains of vertebrate ferritin. The iron-responsive element sequence with a predicted stem-loop structure is present in the 5'-untranslated region of ferritin HCH mRNA. The sequence alignment of ferritin HCH shows 68.9 and 68.7% identity with Galleria mellonella HCH (26 kDa ferritin) and Manduca sexta HCH, respectively. While G type insect ferritin vertebrate light chain homologue (LCH) is distantly related to H. cunea ferritin HCH (17.2-20.8%), the Northern blot analysis revealed that H. cunea ferritin HCH was ubiquitously expressed in various tissues and all developmental stages. The ferritin expression of midgut is more responsive to iron-fed, compared to fat body in H. cunea. 相似文献
18.
Byeong Cheol Moon Byung Kil Choo Myeong Sook Cheon Taesook Yoon Yunui Ji Bo Bae Kim A Young Lee Ho Kyoung Kim 《Plant biotechnology reports》2010,4(1):1-7
Definitive identification of original plant species is important for standardizing herbal medicine. The herbal medicines Cynanchi
Wilfordii Radix (Baekshuoh in Korean and Beishuwu in Chinese) and Polygoni Multiflori Radix (Hashuoh in Korean and Heshuwu in Chinese) are often misidentified in the Korean herbal market due to morphological similarities and similar names. Therefore,
we developed a reliable molecular marker for the identification of Cynanchi Wilfordii Radix and Polygoni Multiflori Radix.
We used random amplified polymorphic DNA (RAPD) analysis of three plant species, Polygoni multiflorum, Cynanchum wilfordii, and Cynanchum auriculatum, to obtain several species-specific RAPD amplicons. From nucleotide sequences of these RAPD amplicons, we developed six sequence
characterized amplification region (SCAR) markers for distinguishing Polygoni Multiflori Radix and Cynanchi Wilfordii Radix.
Furthermore, we established SCAR markers for the simultaneous discrimination of the three species within a single reaction
by using multiplex-PCR. These SCAR markers can be used for efficient and rapid authentication of these closely related species,
and will be useful for preventing the distribution of adulterants. 相似文献
19.
Doo Hyun Chung Kyeong Cheon Jung Weon Seo Park Im-Soon Lee Weon Jin Choi Chong-Jae Kim Seong Hoe Park Youngmee Bae 《Molecules and cells》2001,10(6):642-646
To induce proper immune responses, T lymphocytes require two types of stimuli, antigen-specific and costimulatory signals. Among costimulatory molecules, CD28-engagement promotes the survival and proliferation of both naive and memory T cells. In addition, it is now believed that Fas may play a role in T cell activation in the human system. It is, however, controversial whether Fas can act as a costimulatory signal in the murine system. Thus, we investigated fundamental differences in the capacity to induce proliferation of T cells between Fas and CD28 in mice. Fas-mediated T cell proliferation was observed only with a full mitogenic dose of anti-CD3 antibodies, whereas CD28 engagement was able to enhance T cell proliferation in the presence of a suboptimal level of anti-CD3 antibody. Furthermore, Fas-engaged T cells showed faster response in the upregulation of CD25 and CD69 expression than CD28-engaged ones. Here, we report that Fas might play a role in mature T cell activation in the mouse system through a different mechanism from that in CD28 costimulation. 相似文献
20.
Vasken L. Keleshian Matthew Kellom Hyung-Wook Kim Ameer Y. Taha Yewon Cheon Miki Igarashi Stanley I. Rapoport Jagadeesh S. Rao 《PloS one》2014,9(5)