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191.
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
192.
Kevin McClay Baojie Wan Yuehong Wang Sanghyun Cho Jerry Yu Bernard Santarsiero Shahila Mehboob Michael Johnson Scott Franzblau Robert Steffan 《Applied microbiology and biotechnology》2013,97(16):7151-7163
Two bacterial hosts expressing cloned aromatic oxygenases were used to catalyze the oxidation and polymerization of indole and related substrates, creating mixtures of indigoid compounds comprised of novel dimers and trimers. Crude extracts and purified compounds were tested for their ability to inhibit the growth of Gram-positive organisms, in general, and Mycobacterium tuberculosis (TB), in particular. Of the 74 compounds tested against M. tuberculosis, ~66 % had minimum inhibitory concentrations (MIC) of 5 μg/ml or less. The most effective antibiotic found was designated SAB-P1, a heterodimer of indole and anthranil, which had a MIC of 0.16 μg/ml, and did not inhibit kidney cells (IC50) at concentrations of >8 μg/ml. Combinatorial biocatalysis was used to create a series of halogenated derivatives of SAB-P1 with a wider therapeutic window. None of the derivatives had MIC values that were superior to SAB-P1, but some had a wider therapeutic window because of decreased kidney cell toxicity. Generally, the indigoid dimers that were effective against TB appeared to be specific for TB. Some of the trimers generated, however, had a broader spectrum of activity inhibiting not only TB (MIC?=?1.1 μg/ml) but also the growth of Mycobacterium smegmatis MC2 155, Bacillus cereus, Enterococcus faecalis, Staphylococcus epidermidis, Bacillus subtilis 168, and Clostridium acetobutylicum. The structure of two of the novel dimers (SAB-C4 and SAB-P1) and a trimer (SAB-R1) were solved using X-ray crystallography. 相似文献
193.
Byung-Kook Choi Sang-Hee Jeong Joon-Hyung Cho Hyo-Sook Shin Seong-Wan Son Young-Keun Yeo Hwan-Goo Kang 《Mycotoxin Research》2013,29(3):185-192
Mice were exposed to deoxynivalenol (DON) via drinking water at a concentration of 2 mg/L for 36 days. On day 8 of treatment, inactivated porcine parvovirus vaccine (PPV) was injected intraperitoneally. The relative and absolute weight of the spleen was significantly decreased in the DON-treated group (DON). Antibody titers to parvovirus in serum were 47.9?±?2.4 in the vaccination group (Vac), but 15.2?±?6.5 in the group treated with DON and vaccine (DON?+?Vac). The IgA and IgG was not different in the DON, Vac an,d DON?+?Vac groups. IgM was significantly lower only in the DON?+?Vac group. However IgE was significantly increased in the Vac and DON?+?Vac group, but no change was observed between the Vac and DON?+?Vac groups. The concentrations of IL-2, IL-4, GM-CSF, MCP-1 and Rantes in serum, and IL-1α in mesenteric lymph node and MIP-1β in spleen were significantly increased by DON treatment compared to control. The concentrations of IL-2, IL-5, IL-6, IL-9, IL-12, IL-13 and Rantes in thymus, of IL-2 in spleen, and of IL-1α, IL-1β, IL-3, IL-5, IL-10, IL-17, G-CSF, GM-CSF and MCP-1 in mesenteric lymph nodes were significantly decreased in mice compared to those in the Vac group, while concentrations of IL-1α, IL-2, IL-9, IL-13,G-CSF, GM-CSF, IFN-γ, MCP-1, MIP-1α and TNF-α were significantly increased in serum compared to the Vac group. In conclusion, the results presented here indicate that exposure to DON at 2.0 mg/L via drinking water can disrupt the immune response in vaccinated mice by modulating cytokines and chemokines involved in their immune response to infectious disease. 相似文献
194.
Kyoung Joo Cho Hyun Woo Kim So Yeong Cheon Jong Eun Lee Gyung Whan Kim 《Biochemical and biophysical research communications》2013
Apoptosis signal-regulating kinase-1 (ASK1), an early signaling element in the cell death pathway, has been suggested to participate in the pathology of neurodegenerative diseases, which may be associated with environmental factors that impact the diseases. Although it is not entirely elucidated, 3-nitropropionic acid (3-NP) provokes mitochondrial dysfunction and selectively forms striatal lesions similar to those found in Huntington’s disease. The current study investigated whether ASK1 is involved in striatal pathology following chronic systemic infusion of 3-NP. The results show that ASK1 acts as a primary mediator of there active oxygen species (ROS) cell death signal cascade in the 3-NP-damaged striatal region by disrupting the positive feedback cycle. In 3-NP-infused striatal lesions, ROS increased ASK1. Superoxide dismutase transgenic (SOD-tg) mice reduced ASK1by scavenging ROS, and reduction of ASK1leads to a reduction in cell death. However, ASK1 down-regulation in 3-NP infusion mice also decreased striatal cell death without scavenging ROS. In contrast decreasing cell death by si-ASK1 treatment along with 3-NP in both SOD tg and wild-type mice (wt), cell death rebounded when ASK1 peptide was added to SOD tg mice. The present study suggests that ROS-inducing ASK1 may be an important step in the pathogenesis of 3-NP infused striatal lesions in murine brains. 相似文献
195.
Sunglim Cho Miriam Lee Youngsoo Jun 《Biochemical and biophysical research communications》2013,430(2):787-792
Aberrantly folded proteins in the endoplasmic reticulum (ER) are rapidly removed into the cytosol for degradation by the proteasome via an evolutionarily conserved process termed ER-associated protein degradation (ERAD). ERAD of a subset of proteins requires Derlin-1 for dislocation into the cytosol; however, the molecular function of Derlin-1 remains unclear. Human cytomegalovirus US11 exploits Derlin-1-dependent ERAD to degrade major histocompatibility complex class I (MHC-I) molecules for immune evasion. Because US11 binds to both MHC-I molecules and Derlin-1 via its luminal and transmembrane domains (TMDs), respectively, the major role of US11 has been proposed to simply be delivery of MHC-I molecules to Derlin-1. Here, we directly tested this proposal by generating a hybrid MHC-I molecule, which contains the US11 TMD, and thus can associate with Derlin-1 in the absence of US11. Intriguingly, this MHC-I hybrid was rapidly degraded in a Derlin-1- and proteasome-dependent manner. Similarly, the vesicular stomatitis virus G protein, otherwise expressed at the cell surface, was degraded via Derlin-1-dependent ERAD when its TMD was replaced with that of US11. Thus, forced interaction of cell surface proteins with Derlin-1 is sufficient to induce their degradation via ERAD. Taken together, these results suggest that the main role of US11 is to recruit MHC-I molecules to Derlin-1, which then mediates the dislocation of MHC-I molecules into the cytosol for degradation. 相似文献
196.
Jun Park Yong Hwa Jo Chang Hoon Cho Wonchae Choe Insug Kang Hyung Hwan Baik Kyung-Sik Yoon 《Biochemical and biophysical research communications》2013,430(1):429-435
DNA DSBs are induced by IR or radiomimetic drugs such as doxorubicin. It has been indicated that cells from ataxia-telangiectasia patients are highly sensitive to radiation due to defects in DNA repair, but whether they have impairment in apoptosis has not been fully elucidated. A-T cells showed increased sensitivity to high levels of DNA damage, however, they were more resistant to low doses. Normal cells treated with combination of KU55933, a specific ATM kinase inhibitor, and doxorubicin showed increased resistance as they do in a similar manner to A-T cells. A-T cells have higher viability but more DNA breaks, in addition, the activations of p53 and apoptotic proteins (Bax and caspase-3) were deficient, but Akt expression was enhanced. A-T cells subsequently underwent premature senescence after treatment with a low dose of doxorubicin, which was confirmed by G2 accumulation, senescent morphology, and SA-β-gal positive until 15 days repair incubation. Finally, A-T cells are radio-resistant at low doses due to its defectiveness in detecting DNA damage and apoptosis, but the accumulation of DNA damage leads cells to premature senescence. 相似文献
197.
Seo Young Bang Jeong Hoon Kim Phil Young Lee Seung-Wook Chi Sayeon Cho Gwan-Su Yi Pyung Keun Myung Byoung Chul Park Kwang-Hee Bae Sung Goo Park 《Folia microbiologica》2013,58(5):403-408
In Saccharomyces cerevisiae, the Yap family of basic leucine zipper (bZip) proteins contains eight members. The Yap family proteins are implicated in a variety of stress responses; among these proteins, Yap1 acts as a major regulator of oxidative stress responses. However, the functional roles of the remaining Yap family members are poorly understood. To elucidate the function of Yap2, we mined candidate target genes of Yap2 by proteomic analysis. Among the identified genes, FRM2 was previously identified as a target gene of Yap2, which confirmed the validity of our screening method. YNL134C and YDL124W were also identified as candidate Yap2 target genes. These genes were upregulated in strains overexpressing Yap2 and possess Yap2 target sequences in their promoter regions. Furthermore, chromatin immunoprecipitation assays showed that YNL134C and YDL124W have Yap2 binding motif. These data will help to elucidate the functional role of Yap2. 相似文献
198.
Keiichi Konoki Tatsuya Onoda Sachie Furumochi Yuko Cho Mari Yotsu-Yamashita Takeshi Yasumoto 《Bioorganic & medicinal chemistry letters》2013,23(21):5833-5835
The binding between [24-3H]okadaic acid (OA) and a recombinant OA binding protein OABP2.1 was examined using various OA analog, including methyl okadaate, norokadanone, 7-deoxy OA, and 14,15-dihydro OA, 7-O-palmitoyl DTX1, to investigate the structure activity relationship. Among them, 7-O-palmitoyl DTX1, which is one of the diarrhetic shellfish poisoning (DSP) toxins identified in shellfish, displayed an IC50 for [24-3H]OA binding at 51 ± 6.3 nM (Mean ± SD). In addition, a synthetic compound, N-pyrenylmethyl okadamide, exhibited its IC50 at 10 ± 2.9 nM (Mean ± SD). These results suggested that the recombinant OABP2.1 and the N-pyrenylmethyl okadamide might be core substances in a novel assay for the DSP toxins. 相似文献
199.
Chul-Hong Park Byung Yeoup Chung Seung Sik Lee Hyoung-Woo Bai Jae Young Cho Cheorun Jo Tae Hoon Kim 《Bioorganic & medicinal chemistry letters》2013,23(4):1099-1103
Radiolytic transformation of the isoflavonoid rotenone (1) with γ-irradiation afforded two new degraded products, rotenoisins A (2) and (3). The structures of the two new rotenone derivatives were elucidated on the basis of spectroscopic methods. The new products 2 and 3 exhibited significantly enhanced inhibitory activities against pancreatic lipase and adipocyte differentiation in 3T3-L1 cells when compared to parent rotenone. 相似文献
200.
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