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51.
Won-Kyo Jung Yasantha Athukorala Young-Jae Lee Seon Heui Cha Chi-Ho Lee Thava Vasanthan Kwang-Sik Choi Sang-Ho Yoo Se-Kwon Kim You-Jin Jeon 《Journal of applied phycology》2007,19(5):425-430
Surface plasmon resonance is an important technique for studying molecular interactions and was used to investigate the molecular
interaction of anticoagulant sulfated polysaccharides purified from an enzymatic hydrolysate of the brown alga Ecklonia cava (ECA) with blood coagulation factors. In a direct binding assay, binding affinity between ECA/antithrombin III (ATIII) and
activated blood coagulation factors was in the order: factor VIIa (FVIIa) > factor Xa (FXa) > thrombin (FIIa); kinetic analysis
determined K
D values of ECA for FVIIa, FXa, and FIIa of 15.1, 45.0 and 65.0 nM, respectively. Therefore, ECA strongly and selectively (FVII,
FX, and FII) enhanced ATIII-mediated coagulation factor inhibition in both the extrinsic and common coagulation pathways.
This may contribute to its high anticoagulant activity in vitro. The low cytotoxicity of ECA to venous endothelial cell line
(ECV-304) also expands its value in future in vivo studies. However, to utilize it as a model for novel anticoagulant agents,
its possible interference with other anticoagulant mechanisms must be addressed. 相似文献
52.
A combination of microfluidic protein patterning and quantitative microfluidic handling has been used to analyze the binding kinetics of protein-ligand interactions on the nanoliter scale. The microfluidic handling method employing hydrophobic valving and pneumatic control allowed us to control nanoliter volumes of ligand or protein on a microfluidic chip. A hydrophobic and inert fluorocarbon thin film was patterned on a silicon nitride substrate to prevent non-specific binding on the background. Selectively patterned protein patterns of various sizes were used for quantitative analysis of the kinetic parameters of immobilized proteins on the circular patterns. As a model system, a streptavidin-patterned array of the same-sized pattern, i.e. 150 microm diameter, was used to capture FITC-BSA-biotin present in solution. The fluorescence intensity was well matched with the Langmuir isotherm model results, showing a dissociation constant of 2.43x10(-8)M. Similar streptavidin arrays with different-sized spots, ranging from 50 to 200 microm, showed a consistent dissociation constant of FITC-BSA-biotin with streptavidin pattern. Therefore, the reduction of pattern size of an immobilized protein did not change the dissociation rate of the ligand. 相似文献
53.
Cinnamoyl esterases (CEs) improve the bioavailability of caffeic acid, a potent antioxidant with beneficial health effects. This study aimed to characterize the probiotic properties of 14 strains of CE-producing lactic acid bacteria (LAB) isolated from jeot-gal, a high-salt fermented seafood. We evaluated properties of the probiotic LAB with high CE activity, including tolerance to low pH and bile salts, antimicrobial activity, surface hydrophobicity, adhesion, and immunomodulatory effects, in vitro. All LAB tested tolerated pH 2.0 and 3% Oxgall, i.e., conditions comparable with those in the gastrointestinal environment. Three isolates, Lactobacillus paracasei JBCC10650, Lactobacillus pentosus JBCC10659, and Lactobacillus plantarum JBCC10543, showed stronger adherence to epithelial cells (12.3, 9.6, and 9.4%) than a commercial probiotic Lactobacillus rhamnosus GG (9.1%; p < 0.05), and exhibited broad antibacterial activity against putative pathogens. Most of the 14 LAB strains were able to regulate mRNA expression of pro- and anti-inflammatory cytokines in macrophages, indicating their potential immunomodulatory effects. Our findings suggest that the newly isolated CE-producing probiotics may show beneficial health effects by supporting the host immune system. 相似文献
54.
A-Na Ha Sang-Ryeul Lee Jeong-Seon Jeon Han-Seul Park Sang-Ho Lee Jong-In Jin Benjamin R. Sessions Zhongde Wang Kenneth L. White Il-Keun Kong 《Cryobiology》2014
This study evaluated a modified plastic straw loading method for vitrification of in vitro-produced bovine blastocysts. A modified straw was used with a depressed area on its inner surface to which embryos attach. In vitro-produced blastocysts were randomly assigned into three groups: (i) blastocysts attached to the inner surface of a plastic straw (aV), (ii) blastocysts attached to the inner surface of a modified plastic straw (maV), and (iii) non-vitrified blastocysts (control). The recovery rates were not significantly different between aV and maV groups (95.8% vs. 94.3%). The post-thaw survival rate did not significantly differ between aV and maV groups (86.4% vs. 88.2%). The total cell numbers of blastocyst was higher in control than in aV and maV groups (142 ± 21.8 vs. 117 ± 29.7 and 120 ± 25.2; P < 0.05), but not significantly differ between aV and maV groups. The mRNA levels of pro-apoptosis related genes Bax and Caspase-3 were higher in aV and maV than in control (P < 0.05). By contrast, the mRNA levels of anti-apoptotic genes Bcl-2 and Mcl-1 and of antioxidant-related genes MnSOD and Prdx5 were lower in aV and maV than in control (P < 0.05). Confocal microscopy analysis of Golgi apparatus and mitochondria showed that the fluorescence intensity of Golgi apparatus and mitochondria was higher in control than in aV and maV groups. In conclusion, both aV and maV methods can be used to successfully vitrify IVP blastocysts, with maV method to be preferable because of its easiness in embryo loading. 相似文献
55.
Yon-Suk Kim Jin-Woo Hwang Hyuck-Ju Kwon Won-Young Lee Hyuk Song Jae-Hyun Jeong Si-Heung Sung Sang-Ho Moon Byong-Tae Jeon Pyo-Jam Park 《Biotechnology and Bioprocess Engineering》2014,19(3):411-418
The ability of water and ethanolic extracts isolated of Uncaria rhynchophylla (UR) to function as an anticancer agents was studied using HepG2 cells. The ethanolic UR extract was further fractionatedwith hexane, chloroform (CHCl3), ethyl acetate (EtOAc), n-butanol (n-BuOH), and water, and these fractions were subsequently investigated for anticancer activity. Among the fractions, the n-BuOH fraction induced apoptosis in a dose- and time-dependent manner, when determined by cell cycle analysis, Annexin V-FITC/PI double staining, and Hoechst 33342 staining. Moreover, the n-BuOH fraction induced apoptotic cell death by modulating the expression of caspase-7, caspase-8, and poly ADP ribose polymerase (PARP). These results indicated that the n-BuOH fraction from UR has strong anticancer activity in HepG2 cells and causes an upregulation of apoptotic proteins through the activation of PARP. 相似文献
56.
Joo Myung Lee Jonghanne Park Ki-Hyun Jeon Ji-hyun Jung Sang Eun Lee Jung-Kyu Han Hack-Lyoung Kim Han-Mo Yang Kyung Woo Park Hyun-Jae Kang Bon-Kwon Koo Sang-Ho Jo Hyo-Soo Kim 《PloS one》2014,9(11)
Background
There have been conflicting results across the trials that evaluated prophylactic efficacy of short-term high-dose statin pre-treatment for prevention of contrast-induced acute kidney injury (CIAKI) in patients undergoing coronary angiography (CAG). The aim of the study was to perform an up-to-date meta-analysis regarding the efficacy of high-dose statin pre-treatment in preventing CIAKI.Methods and Results
Randomized-controlled trials comparing high-dose statin versus low-dose statin or placebo pre-treatment for prevention of CIAKI in patients undergoing CAG were included. The primary endpoint was the incidence of CIAKI within 2–5days after CAG. The relative risk (RR) with 95% CI was the effect measure. This analysis included 13 RCTs with 5,825 total patients; about half of them (n = 2,889) were pre-treated with high-dose statin (at least 40 mg of atorvastatin) before CAG, and the remainders (n = 2,936) pretreated with low-dose statin or placebo. In random-effects model, high-dose statin pre-treatment significantly reduced the incidence of CIAKI (RR 0.45, 95% CI 0.35–0.57, p<0.001, I2 = 8.2%, NNT 16), compared with low-dose statin or placebo. The benefit of high-dose statin was consistent in both comparisons with low-dose statin (RR 0.47, 95% CI 0.34–0.65, p<0.001, I2 = 28.4%, NNT 19) or placebo (RR 0.34, 95% CI 0.21–0.58, p<0.001, I2 = 0.0%, NNT 16). In addition, high-dose statin showed significant reduction of CIAKI across various subgroups of chronic kidney disease, acute coronary syndrome, and old age (≥60years), regardless of osmolality of contrast or administration of N-acetylcystein.Conclusions
High-dose statin pre-treatment significantly reduced overall incidence of CIAKI in patients undergoing CAG, and emerges as an effective prophylactic measure to prevent CIAKI. 相似文献57.
The black-veined white, Aporia crataegi (Lepidoptera: Papilionoidea) is nearly extinct in South Korea, although substantial numbers of dried specimens are available. One of the common practices used to rescue such endangered species is to launch a re-introduction program after a proper amount of genetic information is analyzed from donor and donee populations. In this study, we sequenced the complete mitochondrial genome (mitogenome) of A. crataegi to accumulate genetic information for subsequent population studies and to further understand the mitogenome evolution in true butterflies, Papilionoidea. The 15,140-bp long A. crataegi mitogenome has typical sets of 37 genes and is the smallest among the true butterfly species, with overall slightly smaller size genes and regions throughout the genome. The A/T content of the genome (81.3%) is the highest in Pieridae, where A. crataegi belongs, but lower than that of the lycaenid species (81.7%–82.7%). Unlike the diversified or modified usage of an anticodon for tRNASer(AGN), the species of Pieridae including A. crataegi all contain GCT that has been hypothesized as being ancestral for Lepidoptera. A total of 111 bp of non-coding sequences are interspersed in 13 regions, ranging in size from 1–49 bp. Among these sequences, relatively longer ones (≥ 16 bp) all have relatively higher sequence identity to other regions of the genome, suggesting partial duplication of the sequences during A. crataegi evolution. 相似文献
58.
59.
Bae IY Oh IK Lee S Yoo SH Lee HG 《International journal of biological macromolecules》2008,42(1):10-13
Levan polysaccharides were produced from Microbacterium laevaniformans and its rheological behaviors were characterized as a function of concentration and temperature. The intrinsic viscosity of the purified levan was determined to be 0.38dL/g at 25 degrees C which was relatively higher than that of levans from other microbial sources. The flow behaviors of the levan solutions were characterized by the increase in the shear stress, giving more increments in the shear rate. Thus, the levan solutions exhibited the pseudoplastic behavior, which was characterized by the power law model. In addition, the flow behaviors of the levans were satisfactorily fitted to the Arrhenius equation where the activation energy of flow (Ea) decreased from 24.07 to 13.53kJ/mol (R2=0.98-0.99) with increasing concentrations. Moreover, the exponential equation was favorably applied to describe the effect of concentration on the apparent viscosity of the levan polysaccharides. 相似文献
60.
So Youn Won Soo-Jin Kwon Tae-Ho Lee Jae-A Jung Jung Sun Kim Sang-Ho Kang Seong-Han Sohn 《Plant molecular biology》2017,93(4-5):451-463