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161.
162.
Hyeon-Dong Kim Su-Lim Choi Haseong Kim Jung Hoon Sohn Seung-Goo Lee 《Biotechnology and Bioprocess Engineering》2013,18(3):575-580
Cellulose-binding domain (CBD) enriches cellulolytic enzymes on cellulosic surfaces and contributes to the catalytic efficiency by increasing enzyme-substrate complex formations. Thus, high affinity CBDs are essential for the development of efficient cellulose-degrading enzymes. Here, we present a microtiter plate-based assay system to measure the binding affinity of CBDs to cellulose. The assay uses a periplasmic alkaline phosphatase (AP) as a fusion reporter and its activity is detected using a fluorogenic substrate, 4-methylumbelliferyl phosphate. Lignocellulose discs of 6 mm in diameter were used as substrates in 96-well plate. As a result, the enzyme-linked assay detected the binding of CBDs on the cellulosic discs in a highly sensitive manner, detecting from 0.05 to 1.0 μg/mL of APCBD proteins, which is several hundred times more sensitive than conventional protein measurements. The proposed method was applied to compare the binding affinity of different CBDs from Cellulomonas fimi to lignocellulose discs. 相似文献
163.
Jae Hyeong Kim Eun-Kyung Yoon Hye-Jin Chung Seong-Yeol Park Kyeong-Man Hong Chang-Hun Lee Yeon-Su Lee Kyungho Choi Young Yang Kyungtae Kim In-Hoo Kim 《Apoptosis : an international journal on programmed cell death》2013,18(1):110-120
Microtubule inhibitors (MTIs) such as Taxol have been used for treating various malignant tumors. Although MTIs have been known to induce cell death through mitotic arrest, other mechanisms can operate in MTI-induced cell death. Especially, the role of p53 in this process has been controversial for a long time. Here we investigated the function of p53 in Taxol-induced apoptosis using p53 wild type and p53 null cancer cell lines. p53 was upregulated upon Taxol treatment in p53 wild type cells and deletion of p53 diminished Taxol-induced apoptosis. p53 target proteins including MDM2, p21, BAX, and β-isoform of PUMA were also upregulated by Taxol in p53 wild type cells. Conversely, when the wild type p53 was re-introduced into two different p53 null cancer cell lines, Taxol-induced apoptosis was enhanced. Among post-translational modifications that affect p53 stability and function, p53 acetylation, rather than phosphorylation, increased significantly in Taxol-treated cells. When acetylation was enhanced by anti-Sirt1 siRNA or an HDAC inhibitor, Taxol-induced apoptosis was enhanced, which was not observed in p53 null cells. When an acetylation-defective mutant of p53 was re-introduced to p53 null cells, apoptosis was partially reduced compared to the re-introduction of the wild type p53. Thus, p53 plays a pro-apoptotic role in Taxol-induced apoptosis and acetylation of p53 contributes to this pro-apoptotic function in response to Taxol in several human cancer cell lines, suggesting that enhancing acetylation of p53 could have potential implication for increasing the sensitivity of cancer cells to Taxol. 相似文献
164.
Hyo Won Suh Sun-Hee Hyun So-Hyun Kim Seok-Young Lee Hyung-Kyoon Choi 《Process Biochemistry》2013,48(10):1581-1586
In this study, the effects of methyl jasmonate (MJ) and silver nitrate (SN) treatment on metabolic profiles and yields of phytosterols such as campesterol, stigmasterol, and β-sitosterol in whole plant cultures of Lemna paucicostata were investigated using gas chromatography–mass spectrometry coupled with multivariate statistical analysis. The MJ and SN treatments retarded the growth of L. paucicostata plants, while they enhanced the yields of three phytosterols, compared to control. Higher yields of phytosterols were attained at day 28 compared to day 42. Moreover, stigmasterol yield was the highest at 0.85 mg/g from day 28 plants grown under MJ + SN co-treated culture. Among the various metabolites, the levels of palmitic and stearic acids, which might participate in a defense mechanism, were higher in the MJ + SN condition than in control. To determine the optimal timing of MJ + SN addition, MJ + SN was added on days 21, 28, and 35 after inoculation. The total yield and productivity of phytosterol reached maximum levels when the MJ + SN was added at day 35. The highest productivity of stigmasterol (6.08 mg/L) was also achieved when MJ + SN was added on day 35. 相似文献
165.
Jaehoon Choi Jee-Hyeok Chung Geun-Yong Kwon Ki-Wan Kim Sukwha Kim Hak Chang 《Cell and tissue banking》2013,14(3):413-422
In cell culture, medium supplemented with fetal bovine serum is commonly used, and it is widely known that fetal bovine serum supplies an adequate environment for culture and differentiation of stem cells. Nevertheless, the use of xenogeneic serum can cause several problems. We compared the effects of four different concentrations of autologous serum (1, 2, 5, and 10 %) on expansion and adipogenic differentiation of adipose-derived stem cells using 10 % fetal bovine serum as a control. The stem cells were grafted on nude mice and the in vivo differentiation capacity was evaluated. The isolation of adipose-derived stem cells was successful irrespective of the culture medium. The proliferation potential was statistically significant at passage 2, as follows: 10 % autologous serum >10 % fetal bovine serum = 5 % autologous serum >2 % autologous serum = 1 % autologous serum. The differentiation capacity appeared statistically significant at passage 4, as follows: 10 % fetal bovine serum >10 % autologous serum = 5 % autologous serum >2 % autologous serum = 1 % autologous serum. Ten percent autologous serum and 10 % fetal bovine serum had greater differentiation capacity than 1 and 2 % autologous serum in vivo, and no significant difference was observed between the groups at ≥5 % concentration at 14 weeks. In conclusion, 10 % autologous serum was at least as effective as 10 % fetal bovine serum with respect to the number of adipose-derived stem cells at the end of both isolation and expansion, whereas 1 and 2 % autologous serum was inferior. 相似文献
166.
167.
Soo-Kwon Park Do-Yeon Kwak Dong-Soo Park DongJin Shin Woon-Ha Hwang Myung-Hee Kim Yeon-Jae Hur Jun-Hyeon Cho You-Chun Song Ji-Yoon Lee Min-Hee Nam Il-Ryong Choi Jong-Hee Lee 《Molecular breeding : new strategies in plant improvement》2013,32(3):729-733
Green rice leafhopper (GRH, Nephotettix cincticeps Uhler) is one of the insect pests that damage cultivated rice in East Asia. GRH also transmits viruses such as rice dwarf virus. The mortality of GRH nymphs is high in rice cultivar Shingwang, indicating that Shingwang is resistant to GRH. Genetic analyses were performed to map GRH resistance in Shingwang using F2 and F3 populations derived from a cross between a GRH-resistant near-isogenic line (NIL-IS60) from Shingwang and recurrent parent Ilpum. Resistance to GRH in Shingwang was found to be controlled by a single dominant gene (Grh1) mapped within an approximately 670-kb region between 8.10 and 8.77 Mb on the short arm of chromosome 5. Genotypes with three simple sequence repeat markers (RM18166, RM516, and RM18171) and one indel marker (Indel 15040) co-segregated with GRH resistance controlled by the Grh1 locus. A detailed map of the Grh1 locus will facilitate marker-assisted selection of resistance to GRH in rice breeding. 相似文献
168.
Chung-Hwa Park Si Hyun Bae Hee Yeon Kim Ja Kyung Kim Eun Sun Jung Ho Jong Chun Myeong Jun Song Sung-Eun Lee Seok Goo Cho Jong Wook Lee Jong Young Choi Seung Kew Yoon Nam Ik Han Young Sok Lee 《Cytotherapy》2013,15(12):1571-1579
Background aimsMany rodent experiments and human studies on stem cell therapy have shown promising therapeutic approaches to liver diseases. We investigated the clinical outcomes of five patients with liver failure of various causes who received autologous CD34-depleted bone marrow-derived mononuclear cell (BM-MNC) transplantation, including mesenchymal stromal cells, through the hepatic artery.MethodsCD34-depleted BM-MNCs were obtained from five patients waiting for liver transplantation by bone marrow aspiration and using the CliniMACS CD34 Reagent System (Miltenyi Biotech, Bergisch Gladbach, Germany), and autologous hepatic artery infusion was performed. The causes of hepatic decompensation were hepatitis B virus (HBV), hepatitis C virus (HCV), propylthiouracil-induced toxic hepatitis and Wilson disease.ResultsSerum albumin levels improved 1 week after transplantation from 2.8 g/dL, 2.4 g/dL, 2.7 g/dL and 1.9 g/dL to 3.3 g/dL, 3.1 g/dL, 2.8 g/dL and 2.6 g/dL. Transient liver elastography data showed some change from 65 kPa, 33 kPa, 34.8 kPa and undetectable to 46.4 kPa, 19.8 kPa, 29.1 kPa and 67.8 kPa at 4 weeks after transplantation in a patient with Wilson disease, a patient with HCV, and two patients with HBV. Ascites decreased in two patients. One of the patients with HBV underwent liver transplantation 4 months after the infusion, and the hepatic progenitor markers (cytokeratin [CD]-7, CD-8, CD-9, CD-18, CD-19, c-Kit and epithelial cell adhesion molecule [EpCAM]) were highly expressed in the explanted liver.ConclusionsSerum albumin levels, liver stiffness, liver volume, subjective healthiness and quality of life improved in the study patients. Although these findings were observed in a small population, the results may suggest a promising future for autologous CD34-depleted BM-MNC transplantation as a bridge to liver transplantation in patients with liver failure. 相似文献
169.
Janet Lee Jeong-Hwa Baek Kyu-Sil Choi Hyun-Soo Kim Hye-Young Park Geun-Hyoung Ha Ho Park Kyo-Won Lee Chang Geun Lee Dong-Yun Yang Hyo Eun Moon Sun Ha Paek Chang-Woo Lee 《Cell cycle (Georgetown, Tex.)》2013,12(3):442-451
Multipotent mesenchymal stem/stromal cells (MSCs) are capable of differentiating into a variety of cell types from different germ layers. However, the molecular and biochemical mechanisms underlying the transdifferentiation of MSCs into specific cell types still need to be elucidated. In this study, we unexpectedly found that treatment of human adipose- and bone marrow-derived MSCs with cyclin-dependent kinase (CDK) inhibitor, in particular CDK4 inhibitor, selectively led to transdifferentiation into neural cells with a high frequency. Specifically, targeted inhibition of CDK4 expression using recombinant adenovial shRNA induced the neural transdifferentiation of human MSCs. However, the inhibition of CDK4 activity attenuated the syngenic differentiation of human adipose-derived MSCs. Importantly, the forced regulation of CDK4 activity showed reciprocal reversibility between neural differentiation and dedifferentiation of human MSCs. Together, these results provide novel molecular evidence underlying the neural transdifferentiation of human MSCs; in addition, CDK4 signaling appears to act as a molecular switch from syngenic differentiation to neural transdifferentiation of human MSCs. 相似文献
170.
Jun Seo Goo Yo Na Kim Kyung Mi Choi In Sik Hwang Ji Eun Kim Young Ju Lee Moon Hwa Kwak Sun Bo Shim Seung Wan Jee Chul Joo Lim Je Kyung Seong Dae Youn Hwang 《Clinical proteomics》2013,10(1):10