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61.
Hong SW Jung KH Lee HS Zheng HM Choi MJ Lee C Hong SS 《Bioscience, biotechnology, and biochemistry》2011,75(5):833-840
Fucoidan, a sulfated polysaccharide extracted from various types of brown seaweed, possesses a wide range of pharmacological properties. We investigated the protective effect of fucoidan on dimethylnitrosamine-induced liver fibrogenesis in rats and its mechanism. Liver fibrosis was induced by injecting DMN (10 mg/kg, 3 times per week, I.P.) for 4 weeks, and fucoidan was simultaneously administered (100 mg/kg, 3 times per week, P.O.). The anti-oxidative and anti-inflammatory effects of fucoidan were observed by relative mediators. Fucoidan improved liver fibrosis by inhibiting the expression of transforming growth factor beta 1 (TGF-β(1))/Smad3 and the tissue inhibitor of metalloproteinase 1 (TIMP-1), and increasing the expression of metalloproteinase-9 (MMP-9). Fucoidan also significantly decreased the accumulation of the extracellular matrix (ECM) and collagen. These results suggest that fucoidan had an anti-fibrotic effect, which was exerted by inhibiting the TGF-β/Smad pathway, as well as anti-oxidative and anti-inflammatory effects. 相似文献
62.
A plant growth-promoting rhizobacterium (PGPR) was isolated and identified as Gordonia sp. S2RP-17, which showed ACC deaminase and siderophore synthesizing activities. Its maximum specific growth rate was 0.54 ± 0.12 d−1 at 5,000 mg L−1 of total petroleum hydrocarbon (TPH), and its maximum diesel degradation rate was 2,434.0 ± 124.4 mg L−1 d−1 at 20,000 mg L−1 of TPH. The growth of Zea mays was significantly promoted by the inoculation of Gordonia sp. S2RP-17 in the diesel-contaminated soil. Measured TPH removal efficiencies by various means were 13% by natural attenuation,
84.5% by planting Zea mays, and 95.8% by the combination of Zea mays and Gordonia sp. S2RP-17. The S2RP-17 cell counts were maintained at 1 × 106 CFU g-soil−1 during the remediation period, although they slightly decreased from their initial numbers (2.94 × 107 CFU g-soil−1). These results indicate that rhizoremediation using both Zea mays and Gordonia sp. S2RP-17 is a promising strategy for enhancing remediation efficiency of diesel-contaminated soils. 相似文献
63.
Zhou J Tun TN Hong SH Mercer-Chalmers JD Laabei M Young AE Jenkins AT 《Biosensors & bioelectronics》2011,30(1):67-72
A new methodology for detecting the microbiological state of a wound dressing in terms of its colonization with pathogenic bacteria such as Staphylococcus aureus or Pseudomonas aeruginosa has been developed. Here we report how stabilized lipid vesicles containing self-quenched carboxyfluorescein dye are sensitive to lysis only by toxins/virulence factors from P. aeruginosa and S. aureus but not by a non-toxic Escherichia coli species. The development of the stabilized vesicles is discussed and their response to detergent (triton), bacterial toxin (α-hemolysin) and lipases (phospholipase A2). Finally, fabrics with stabilized vesicles attached via plasma deposited maleic anhydride coupling are shown visibly responding to S. aureus (MSSA 476) and P. aeruginosa (PAO1) but not E. coli DH5α in a prototype dressing. 相似文献
64.
Ahn J Lee TH Li T Heo K Hong S Ko J Kim Y Shin YB Kim MG 《Biosensors & bioelectronics》2011,26(12):4690-4696
We demonstrated that the detection of human interleukin 5 (IL5) with a higher sensitivity than the enzyme-linked immunosorbent assay (ELISA) was possible using mass-producible submicron-gap interdigitated electrodes (IDEs) combined with signal amplification by a gold nanoparticle (AuNP) and gold enhancement. IDEs, facing comb-shape electrodes, can act as simple and miniaturized devices for immunoassay. An IDE with a gap size of 400nm was fabricated by a stepper photolithography process and was applied for the immunoassay of human IL5. A biotinylated anti-human IL5 was immobilized on the streptavidin-modified IDE, and biotin-bovine serum albumin (BSA) and BSA were added sequentially to reduce non-specific binding between the streptavidin-immobilized IDE surface and other proteins. The immunoassay procedure included three main steps: the reaction of human IL5 to form antigen-antibody complexes, the binding of AuNP conjugation with an antibody against human IL5 for the sandwich immunoassay, and gold enhancement for electrical signal amplification. The measurement of electrical current at each step showed that the gold enhancement step was very critical in detection of the concentration of human IL5. Analysis by scanning electron microscope (SEM) showed that close to 1μm particles were formed from 10nm AuNP by the gold enhancement reaction using gold ions and hydroxylamine. Under optimized conditions, human IL5 could be analyzed at 1pgmL(-1) with a wide dynamic range (from 10(-3) to 100ngmL(-1) concentrations). 相似文献
65.
The formation and refinement of synaptic circuits are areas of research that have fascinated neurobiologists for decades. A recurrent theme seen at many CNS synapses is that neuronal connections are at first imprecise, but refine and can be rearranged with time or with experience. Today, with the advent of new technologies to map and monitor neuronal circuits, it is worthwhile to revisit a powerful experimental model for examining the development and plasticity of synaptic circuits--the retinogeniculate synapse. 相似文献
66.
67.
Lee YS Choi KM Choi MH Ji SY Lee S Sin DM Oh KW Lee YM Hong JT Yun YP Yoo HS 《Cell proliferation》2011,44(4):320-329
Objectives: Melanoma is the most aggressive form of skin cancer, and it resists chemotherapy. Candidate drugs for effective anti‐cancer treatment have been sought from natural resources. Here, we have investigated anti‐proliferative activity of myriocin, serine palmitoyltransferase inhibitor, in the de novo sphingolipid pathway, and its mechanism in B16F10 melanoma cells. Material and methods: We assessed cell population growth by measuring cell numbers, DNA synthesis, cell cycle progression, and expression of cell cycle regulatory proteins. Ceramide, sphingomyelin, sphingosine and sphingosine‐1‐phosphate levels were analysed by HPLC. Results: Myriocin inhibited proliferation of melanoma cells and induced cell cycle arrest in the G2/M phase. Expressions of cdc25C, cyclin B1 and cdc2 were decreased in the cells after exposure to myriocin, while expression of p53 and p21waf1/cip1 was increased. Levels of ceramide, sphingomyelin, sphingosine and sphingosine‐1‐phosphate in myriocin‐treated cells after 24 h were reduced by approximately 86%, 57%, 75% and 38%, respectively, compared to levels in control cells. Conclusions: Our results suggest that inhibition of sphingolipid synthesis by myriocin in melanoma cells may inhibit expression of cdc25C or activate expression of p53 and p21waf1/cip1, followed by inhibition of cyclin B1 and cdc2, resulting in G2/M arrest of the cell cycle and cell population growth inhibition. Thus, modulation of sphingolipid metabolism by myriocin may be a potential target of mechanism‐based therapy for this type of skin cancer. 相似文献
68.
Yang Y Miller KJ Zhu Y Hong Y Tian Y Murugesan N Gu Z O'Tanyi E Keim WJ Rohrbach KW Johnghar S Behnia K Pelleymounter MA Carlson KE Ewing WR 《Bioorganic & medicinal chemistry letters》2011,21(22):6856-6860
Obesity remains a significant public health issue leading to Type II diabetes and cardiovascular disease. CB1 antagonists have been shown to suppress appetite and reduce body weight in animal models as well as in humans. Evaluation of pre-clinical CB1 antagonists to establish relationships between in vitro affinity and in vivo efficacy parameters are enhanced by ex vivo receptor occupancy data. Synthesis and biological evaluation of a novel and highly selective radiolabeled CB1 antagonist is described. The radioligand was used to conduct ex vivo receptor occupancy studies. 相似文献
69.
Wang GZ Haile PA Daniel T Belot B Viet AQ Goodman KB Sha D Dowdell SE Varga N Hong X Chakravorty S Webb C Cornejo C Olzinski A Bernard R Evans C Emmons A Briand J Chung CW Quek R Lee D Gough PJ Sehon CA 《Bioorganic & medicinal chemistry letters》2011,21(24):7291-7294
A series of biarylsulfonamides was identified as hCCR2 receptor antagonist but suffered from high plasma protein binding resulting in a >100 fold shift in activity in a functional GTPγS assay run in tandem in the presence and absence of human serum albumin. Introduction of an aryl amide with ethylenediamine linker led to compounds with reduced shifts and improved activity in whole blood. 相似文献
70.