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221.
Yi DK Sun IC Ryu JH Koo H Park CW Youn IC Choi K Kwon IC Kim K Ahn CH 《Bioconjugate chemistry》2010,21(12):2173-2177
Herein, we developed matrix metalloprotease (MMP) sensitive gold nanorods (MMP-AuNR) for cancer imaging and therapy. It was feasible to absorb NIR laser and convert into heat as well as visualize MMP activity. We showed the possibility of gold nanorods as a hyperthermal therapeutic agent and MMP sensitive imaging agent both in vitro and in vivo condition. The results suggested potential application of MMP-AuNR for simultaneous cancer diagnosis and therapy. 相似文献
222.
Nack-Shick Choi Dong-Min Chung Chan-Sun Park Keug-Hyun Ahn Joong Su Kim Jae Jun Song Seung-Ho Kim Byung-Dae Yoon Min-Soo Kim 《Biotechnology and Bioprocess Engineering》2010,15(3):446-452
Previously, three extracellular proteases, Vpr, PepT, and subtilisin were identified from Bacillus subtilis KCTC 3014. To confirm the activity of Vpr, two recombinant Vpr proteins, full Vpr with TTG (pGST-fTTG-Vpr) and full Vpr with
ATG (pGST-fATG-Vpr) as an initiation codon were expressed using a pGEX-2T vector encoding glutathione S-transferase (GST)
in Escherichia coli. Vpr was produced in two forms, occurring as four spots on a 2-DE gel, 68 and 75 kDa proteins with similar pI values (4.0
∼ 4.5). Activity was detected in a fibrin zymography at the expected molecular size of 68 kDa (mature form) processed from
full Vpr. However, the recombinant 75 kDa of GST-fVpr did not exhibit activity. Replacement of the TTG codon with ATG led
to 1.9-fold increased enzyme activity in 68 kDa. Interestingly, the expression of GSTVpr resulted in the proteolytic degradation
of the protein and no GST fusion Vpr protein was detected. 相似文献
223.
Xia Y Chackalamannil S Greenlee WJ Wang Y Hu Z Root Y Wong J Kong J Ahn HS Boykow G Hsieh Y Kurowski S Chintala M 《Bioorganic & medicinal chemistry letters》2010,20(22):6676-6679
An analog of the thrombin receptor antagonist vorapaxar (SCH 530348) with increased aqueous solubility, compound 9c (SCH 602539), was discovered through incorporation of polar substituents on the pyridine ring of the himbacine-derived lead series. This analog retained the excellent potency, pharmacokinetic and safety properties of vorapaxar while increasing the aqueous solubility by 20-fold. Also presented are in vivo evaluations of this compound in a cynomolgus monkey platelet aggregation assay and in a Folts model of thrombosis in anesthetized monkeys. 相似文献
224.
Kyung Sook Chung So Yeon Yoo Seong Jeon Yoo Jong Seob Lee Ji Hoon Ahn 《Plant signaling & behavior》2010,5(9):1102-1104
Transition to the flowering stage is precisely controlled by a few classes of regulatory molecules. BROTHER OF FT AND TFL1 (BFT) is a member of FLOWERING LOCUS T (FT)/TERMINAL FLOWER 1 (TFL1) family, an important class of flower development regulators with unidentified biochemical function. BFT has a TFL1-like activity and plays a role in axillary inflorescence development. To elucidate the expression pattern of BFT, we analyzed the subcellular localization and conditional expression of BFT in this study. We generated 35S::BFT:GFP plants to investigate the subcellular localization of BFT protein. 35S::BFT:GFP plants showed late flowering, similarly as did 35S::BFT plants. BFT:GFP fusion protein was localized in the nucleus and the plasma membrane, which was different from the localization pattern of FT and TFL1. BFT expression was induced by abiotic stress conditions. ABA, drought, and osmotic stress treatments induced BFT expression, whereas cold, salt, and heat stress conditions did not, suggesting that BFT plays a role in regulating flowering time and inflorescence structure under drought conditions. The induction pattern of BFT was different from those of other FT/TFL1 family genes. Our studies indicated that BFT showed a distinct expression pattern from its homologous genes during the vegetative growth in Arabidopsis.Key words: flowering time, flowering locus T, terminal flower 1, brother of FT and TFL1, abiotic stress, subcellullar localizationThe FLOWERING LOCUS T (FT)/TERMINAL FLOWER 1 (TFL1) family is a small gene family whose members play a pivotal role in flower development in Arabidopsis. The family includes FT, TFL1, TWIN SISTER OF FT (TSF), Arabidopsis thaliana CENTRORADIALIS homologue (ATC), MOTHER OF FT AND TFL1 (MFT) and BROTHER OF FT AND TFL1 (BFT).3,5,6,9,15,17 FT is a floral promoter that integrates signal inputs from various pathways that regulate flowering time in Arabidopsis.5,6 TFL1 plays an antagonistic role to that of FT, functioning as a floral inhibitor. Unlike FT, TFL1 also plays an important role in controlling plant architecture by regulating the expression of LEAFY (LFY) and APETALA1 (AP1), two important floral meristem identity genes in the shoot apical meristem (SAM).3,7 TSF regulates flowering by a mechanism similar to that of FT, although a lesion in TSF does not have an apparent effect on the determination of flowering time. MFT has a weak FT-like activity.17 ATC acts as a floral repressor, and its role is similar to that of TFL1.9 Finally, BFT has a TFL1-like activity, in spite of its amino acid homology to FT,2,4,16 and functions redundantly with TFL1 in inflorescence meristem development in Arabidopsis.16 Although genetic studies elucidated an intricate role of the FT/TFL1 family genes, not much is known about the expression pattern of the remaining members except FT and TFL1. Here, we report that BFT expression showed a distinct pattern from its homologous genes during the vegetative phase. BFT:GFP fusion protein was detected in the nucleus and the plasma membrane. BFT expression was induced by abiotic stress conditions, distinct from other FT/TFL1 family genes, raising the possibility that BFT plays a role in regulating flowering time and inflorescence structure under drought conditions. 相似文献
225.
Selenium (Se), a dietary trace metal essential for human health, is incorporated into ~25 selenoproteins including selenoprotein S (SelS) and the 15-kDa selenoprotein (Sep15) both of which have functions in the endoplasmic reticulum protein unfolding response. The aim of this study was to investigate whether genetic variants in such selenoprotein genes are associated with altered risk of colorectal cancer (CRC). A Korean population of 827 patients with CRC and 733 healthy controls was genotyped for 7 SNPs in selenoprotein genes and one SNP in the gene encoding manganese superoxide dismutase using Sequenom technology. Multivariate logistic regression analysis showed that after adjustment for lifestyle factors three SNP variants were associated with altered disease risk. There was a mean odds ratio of 2.25 [95% CI 1.13,4.48] in females homozygous TT for rs34713741 in SELS with the T variant being associated with higher risk of rectal cancer, and odds ratios of 2.47 and 2.51, respectively, for rs5845 and rs5859 in SEP15 with the minor A and T alleles being associated with increased risk of male rectal cancer. The data indicate that the minor alleles for rs5845, rs5859 and rs34713741 are associated with increased rectal cancer risk and that the effects of the three SNPs are dependent on gender. The results highlight potential links between Se, the function of two selenoproteins involved in the protein unfolding response and CRC risk. Further studies are required to investigate whether the effects of the variants on CRC risk are also modulated by dietary Se intake. 相似文献
226.
Jeong-Whun Kim Gwang Lee Seung-Min Moon Myung-June Park Sung Kyu Hong Young-Hwan Ahn Kyoung-Rae Kim Man-Jeong Paik 《Metabolomics : Official journal of the Metabolomic Society》2010,6(2):202-206
Metabolomic analysis of urinary amino acids (AAs) from patients with bladder cancer was performed by gas chromatography–mass
spectrometry. The β-aminoisobutyric acid (P < 0.05) and pyroglutamic acid (P < 0.03) levels among 21 AAs had relatively low P-values in the cancer group. The distorted star pattern of the cancer group was different from the heneicosagonal shape of
the control mean. The present metabolomic screening combined with star pattern recognition method as clinical monitoring tool
might be useful for the visual discrimination of bladder cancer group from normal group. 相似文献
227.
Biosynthesis of flavonoid derivatives requires enzyme(s) having high reactivity as well as regioselectivity. We have synthesized
3-O-kaempferol from naringenin using two enzymes. The first reaction, in which naringenin is converted to kaempferol, is mediated
by flavonol synthase (FLS). An FLS (PFLS) with strong catalytic activity was cloned and characterized from the genome sequence of the poplar (Populus deltoides). PFLS consists of a 1,008 bp ORF encoding a 38 kDa protein. PFLS was expressed in Escherichia coli with a glutathione-S-transferase (GST) tagging. The purified recombinant PFLS was characterized. Catalytically, it was more efficient than the
previously characterized FLSs. A mixture of two E. coli transformants harboring either PFLS or ROMT9 (a kaempferol 3-O-methyltransferase) converted naringenin into 3-O-methylkaempferol. 相似文献
228.
Ahn G Park JH Kang T Lee JW Kang HW Cho DW 《Journal of biomechanical engineering》2010,132(10):104506
The aim of this study was to maximize oxygen diffusion within a three-dimensional scaffold in order to improve cell viability and proliferation. To evaluate the effect of pore architecture on oxygen diffusion, we designed a regular channel shape with uniform diameter, referred to as cylinder shaped, and a new channel shape with a channel diameter gradient, referred to as cone shaped. A numerical analysis predicted higher oxygen concentration in the cone-shaped channels than in the cylinder-shaped channels, throughout the scaffold. To confirm these numerical results, we examined cell proliferation and viability in 2D constructs and 3D scaffolds. Cell culture experiments revealed that cell proliferation and viability were superior in the constructs and scaffolds with cone-shaped channels. 相似文献
229.
230.
Hee-Joo Kim Ki Chang Ahn Shirley J. Gee Bruce D. Hammock 《Analytical biochemistry》2010,401(1):38-253
We present a new application of the noncompetitive phage anti-immunocomplex assay (PHAIA) by converting an existing competitive assay to a versatile noncompetitive sandwich-type format using immunocomplex binding phage-borne peptides to detect the brominated flame retardant, brominated diphenyl ether 47 (BDE 47). Three phage-displayed 9-mer disulfide-constrained peptides that recognize the BDE 47-polyclonal antibody immunocomplex were isolated. The resulting PHAIAs showed variable sensitivities, and the most sensitive peptide had a dose-response curve with an SC50 (concentration of analyte producing 50% saturation of the signal) of 0.7 ng/ml BDE 47 and a linear range of 0.3-2 ng/ml, which was nearly identical to the best heterologous competitive format (IC50 of 1.8 ng/ml, linear range of 0.4-8.5/ml). However, the PHAIA was 1400-fold better than homologous competitive assay. The validation of the PHAIA with extracts of house furniture foam as well as human and calf sera spiked with BDE 47 showed overall recovery of 80-113%. The PHAIA was adapted to a dipstick format (limit of detection of 3.0 ng/ml), and a blind test with six random extracts of local house furniture foams showed that the results of the PHAIA and dipstick assay were consistent, giving the same positive and negative detection. 相似文献