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61.
Jingrang Lu Hodon Ryu Jason Vogel Jorge Santo Domingo Nicholas J. Ashbolt 《Applied and environmental microbiology》2013,79(12):3762-3769
The risk to human health of the annual sandhill crane (Grus canadensis) migration through Nebraska, which is thought to be a major source of fecal pollution of the central Platte River, is unknown. To better understand potential risks, the presence of Campylobacter species and three fecal indicator bacterial groups (Enterococcus spp., Escherichia coli, and Bacteroidetes) was assayed by PCR from crane excreta and water samples collected during their stopover at the Platte River, Nebraska, in 2010. Genus-specific PCR assays and sequence analyses identified Campylobacter jejuni as the predominant Campylobacter species in sandhill crane excreta. Campylobacter spp. were detected in 48% of crane excreta, 24% of water samples, and 11% of sediment samples. The estimated densities of Enterococcus spp. were highest in excreta samples (mean, 4.6 × 108 cell equivalents [CE]/g), while water samples contained higher levels of Bacteroidetes (mean, 5.1 × 105 CE/100 ml). Enterococcus spp., E. coli, and Campylobacter spp. were significantly increased in river water and sediments during the crane migration period, with Enterococcus sp. densities (∼3.3 × 105 CE/g) 2 to 4 orders of magnitude higher than those of Bacteroidetes (4.9 × 103 CE/g), E. coli (2.2 × 103 CE/g), and Campylobacter spp. (37 CE/g). Sequencing data for the 16S rRNA gene and Campylobacter species-specific PCR assays indicated that C. jejuni was the major Campylobacter species present in water, sediments, and crane excreta. Overall, migration appeared to result in a significant, but temporary, change in water quality in spring, when there may be a C. jejuni health hazard associated with water and crops visited by the migrating birds. 相似文献
62.
JuKyung Lee SiHyeong Cho JungHwan Lee HeonYul Ryu JinGoo Park SunHee Lim ByungDo Oh ChangWoo Lee Wilber Huang Ahmed Busnaina HeaYeon Lee 《Journal of biotechnology》2013
We have reported that nanowell array (NWA) can enhance electrochemical detection of molecular binding events by controlling the binding sites of the captured molecules. Using NWA biosensor based amperometric analysis, we have detected biological macromolecules such as DNA, protein or aptamers at low concentrations. In this research, we developed an impedimetric immunosensor based on wafer-scale NWA for electrochemical detection of stress-induced-phosphoprotein-1 (STIP-1). In order to develop NWA sensor through the cost-effective combination of high-throughput nanopattern, the NWA electrode was fabricated on Si wafer by krypton-fluoride (KrF) stepper semiconductor process. Finally, 12,500,000 ea nanowell with a 500 nm diameter was fabricated on 4 mm × 2 mm substrate. Next, by using these electrodes, we measured impedance to quantify antigen binding to the immunoaffinity layer. The limit of detection (LOD) of the NWA was improved about 100-fold compared to milli-sized electrodes (4 mm × 2 mm) without an NWA. These results suggest that wafer-scale NWA immunosensor will be useful for biosensing applications because their interface response is appropriate for detecting molecular binding events. 相似文献
63.
Yongfeng He Hangun Kim Taeyong Ryu Youra Kang Jeong-Ae Kim Bo-Hyun Kim Jae-Hyuk Lee Keonwook Kang Qun Lu Kwonseop Kim 《FEBS letters》2013,587(2):193-199
This study revealed that CWR22Rv-1 cells overexpressing δ-catenin display bigger tumor formation and higher angiogenic potentials than their matched control cells in the CAM assay. In addition, δ-catenin overexpression in CWR22Rv-1 cells results in increased hypoxia-inducible factor 1-alpha (HIF-1α and vascular endothelial growth factor (VEGF) expression. Furthermore, δ-catenin overexpression was found to enhance nuclear distribution of both β-catenin and HIF-1α in hypoxic condition, which is diminished by knockdown of δ-catenin. Our current study adds novel evidence regarding contribution of δ-catenin to the progression of prostate cancer. 相似文献
64.
Nguyen The Tung To Dao Cuong Tran Manh Hung Jeong Hyung Lee Mi Hee Woo Jae Sue Choi Jaewang Kim Sung Ho Ryu Byung Sun Min 《Bioorganic & medicinal chemistry letters》2013,23(5):1428-1432
Four new lanostane triterpenes, butyl lucidenate P (1), butyl lucidenate D2 (2), butyl lucidenate E2 (3) and butyl lucidenate Q (4) along with 11 known compounds (5–15) were isolated from the fruiting bodies of Ganoderma lucidum. Their chemical structures were established mainly by 1D and 2D NMR techniques and mass spectrometry. Their anti-inflammatory activity was evaluated against LPS-induced NO production in macrophage RAW 264.7 cells. Compounds 1, 3, 4, 9, 10 and 15 showed inhibitory potency with IC50 values of 7.4, 6.4, 4.3, 9.4, 9.2 and 4.5 μM, respectively. Compounds 1, 3 and 15 dose-dependently reduced the LPS-induced iNOS expressions. Preincubation of cell with 1, 3 and 15 significantly suppressed LPS-induced expression of COX-2 protein. 相似文献
65.
Bryan D. Yestrepsky Yuanxi Xu Meghan E. Breen Xiaoqin Li Walajapet G. Rajeswaran Jenny G. Ryu Roderick J. Sorenson Yasuhiro Tsume Michael W. Wilson Wenpeng Zhang Duxin Sun Hongmin Sun Scott D. Larsen 《Bioorganic & medicinal chemistry》2013,21(7):1880-1897
Resistance to antibiotics is an increasingly dire threat to human health that warrants the development of new modes of treating infection. We recently identified 1 (CCG-2979) as an inhibitor of the expression of streptokinase, a critical virulence factor in Group A Streptococcus that endows blood-borne bacteria with fibrinolytic capabilities. In this report, we describe the synthesis and biological evaluation of a series of novel 5,6-dihydrobenzo[h]quinazolin-4(3H)-one analogs of 1 undertaken with the goal of improving the modest potency of the lead. In addition to achieving an over 35-fold increase in potency, we identified structural modifications that improve the solubility and metabolic stability of the scaffold. The efficacy of two new compounds 12c (CCG-203592) and 12k (CCG-205363) against biofilm formation in Staphylococcus aureus represents a promising additional mode of action for this novel class of compounds. 相似文献
66.
Hironobu Morinaga Seiichiro Kizaki Tomohiro Takenaka Shuhei Kanesato Yuta Sannohe Ryu Tashiro Hiroshi Sugiyama 《Bioorganic & medicinal chemistry》2013,21(2):466-469
5-Bromouracil (BrU) was incorporated into three types of synthetic RNA and the products of the photoirradiated BrU-containing RNAs were investigated using HPLC and MS analysis. The photoirradiation of r(GCABrUGC)2 and r(CGAABrUUGC)/r(GCAAUUCG) in A-form RNA produced the corresponding 2′-keto adenosine (ketoA) product at the 5′-neighboring nucleotide, such as r(GCketoAUGC) and r(CGAketoAUUGC), respectively. The photoirradiation of r(CGCGBrUGCG)/r(CmGCACmGCG) in Z-form RNA produced the 2′-keto guanosine (ketoG) product r(CGCketoGUGCG), whereas almost no products were observed from the photoirradiation of r(CGCGBrUGCG)/r(CmGCACmGCG) in A-form RNA. The present results indicate clearly that hydrogen (H) abstraction by the photochemically generated uracil-5-yl radical selectively occurs at the C2′ position to provide a 2′-keto RNA product. 相似文献
67.
Tae-Hwan Ha HyungChul Ryu Sung-Eun Kim Ho Shin Kim Jihyae Ann Phuong-Thao Tran Van-Hai Hoang Karam Son Minghua Cui Sun Choi Peter M. Blumberg Robert Frank Gregor Bahrenberg Klaus Schiene Thomas Christoph Sven Frormann Jeewoo Lee 《Bioorganic & medicinal chemistry》2013,21(21):6657-6664
A series of 2-thio pyridine C-region analogues of 2-(3-fluoro-4-methylsulfonylaminophenyl)propanamides were investigated as hTRPV1 antagonists. Among them, compound 24S showed stereospecific and excellent TRPV1 antagonism of capsaicin-induced activation. Further, it demonstrated strong anti-allodynic in a rat neuropathic pain model. Consistent with its action in vitro being through TRPV1, compound 24S blocked capsaicin-induced hypothermia in mice. Docking analysis of 24S with our hTRPV1 homology model was performed to identify its binding mode. 相似文献
68.
Hyung-Jun Kwon Young Bae Ryu Young-Min Kim Naaleum Song Cha Young Kim Mun-Chual Rho Jae-Ho Jeong Kyoung-Oh Cho Woo Song Lee Su-Jin Park 《Bioorganic & medicinal chemistry》2013,21(15):4706-4713
Despite the prepdominat agent causing severe entero-pathogenic diarrhea in swine, there are no effective therapeutical treatment of porcine epidemic diarrhea virus (PEDV). In this study, we evaluated the antiviral activity of five phlorotannins isolated from Ecklonia cava (E. cava) against PEDV. In vitro antiviral activity was tested using two different assay strategies: (1) blockage of the binding of virus to cells (simultaneous-treatment assay) and (2) inhibition of viral replication (post-treatment assay). In simultaneous-treatment assay, compounds 2–5 except compound 1 exhibited antiviral activities of a 50% inhibitory concentration (IC50) with the ranging from 10.8 ± 1.4 to 22.5 ± 2.2 μM against PEDV. Compounds 1–5 were completely blocked binding of viral spike protein to sialic acids at less than 36.6 μM concentrations by hemagglutination inhibition. Moreover, compounds 4 and 5 of five phlorotannins inhibited viral replication with IC50 values of 12.2 ± 2.8 and 14.6 ± 1.3 μM in the post-treatment assay, respectively. During virus replication steps, compounds 4 and 5 exhibited stronger inhibition of viral RNA and viral protein synthesis in late stages (18 and 24 h) than in early stages (6 and 12 h). Interestingly, compounds 4 and 5 inhibited both viral entry by hemagglutination inhibition and viral replication by inhibition of viral RNA and viral protein synthesis, but not viral protease. These results suggest that compounds isolated from E. cava have strong antiviral activity against PEDV, inhibiting viral entry and/or viral replication, and may be developed into natural therapeutic drugs against coronavirus infection. 相似文献
69.
Targeted delivery of a phosphopeptide prodrug inhibits the proliferation of a human glioma cell line
Peptides are ideal candidates for developing therapeutics. Polo-like kinase 1 is an important regulatory protein in the cell cycle and contains a C-terminal polo-box domain, which is the hallmark of this protein family. We developed a peptide inhibitor of polo-like kinase 1 that targets its polo-box domain. This new phosphopeptide, cRGDyK-S-S-CPLHSpT, preferentially penetrates the cancer cell membrane mediated by the integrin receptor, which is expressed at high levels by cancer cells. In the present study, using high performance liquid chromatography and mass spectroscopy, we determined the stability of cRGDyK-S-S-CPLHSpT and its cleavage by glutathione under typical conditions for cell culture. We further assessed the ability of the peptide to inhibit the proliferation of the U87MG glioma cell line. The phosphorylated peptide was stable, and the disulfide bond of cRGDyK-S-S-CPLHSpT was cleaved in 50 mM glutathione. This peptide inhibited the growth of cancer cells and changed their morphology. Therefore, we conclude that the phosphopeptide shows promise as a prodrug and has a high potential to act as an anticancer agent by inhibiting polo-like kinase 1 by binding its polo-box domain. These findings indicate the therapeutic potential of PLHSpT and peptides similarly targeted to surface receptors of cancer cells and to the functional domains of regulatory proteins. 相似文献
70.
Yup Kang Jung H. Kim Dewey D. Y. Ryu 《Bioscience, biotechnology, and biochemistry》2013,77(8):2221-2227
Lactobacillus casei ATCC 7469 was successfully converted to protoplasts by treatment with endo-7V-acetyl muramidase in sucrose phosphate buffer. For full hydrolysis of cell walls, a high concentration of sucrose and a cold shock were necessary. Mg2+ ions enhanced the stability of protoplasting cells. The cell wall regeneration of protoplasts was more effective on gelatin-induced regeneration medium than with the soft overlay method. The optimal concentration of gelatin was 2.5%. The frequency of regeneration was found to be about 6% for the protoplast prepared by enzyme treatment for 20 min. The mutants having streptomycin resistance and rifampicin resistance, as selection markers for the detection of fusion, were isolated by UV irradiation and NTG treatment. These mutants were stable for at least several transfers. Protoplast fusion was carried out using PEG (50% solution of polyethyleneglycol, M.W. 6,000). The frequency of protoplast fusion was found to be about 10-5. 相似文献