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41.
Byeon HE  Um SH  Yim JH  Lee HK  Pyo S 《Life sciences》2012,90(11-12):396-406
AimsThe expression of cell adhesion molecules on vascular smooth muscle cells is central to leukocyte recruitment and progression of atherosclerotic disease. Ohioensin F, a chemical compound of the Antarctic moss Polyerichastrum alpinum, exhibited inhibitory activity against protein tyrosine phosphatase 1B and antioxidant activity. However, published scientific information regarding other biological activities and pharmacological function of ohioensin F is scarce. In the present study, we aimed to examine the in vitro effects of ohioensin F on the ability to suppress TNF-α-induced adhesion molecule expression in vascular smooth muscle cells (VSMCs).Main methodsThe inhibitory effect of ohioensin F on TNF-α-induced upregulation in expression of adhesion molecules was investigated by enzyme-linked immunosorbent assay, cell adhesion assay, RT-PCR, western blot analysis, immunofluorescence, and transfection and reporter assay, respectively.Key findingsPretreatment of VSMCs with ohioensin F at nontoxic concentrations of 0.1–10 μg/ml dose-dependently inhibited TNF-α-induced expression of vascular cell adhesion molecule-1 (VCAM-1) and intercellular adhesion molecule-1 (ICAM-1). In addition, ohioensin F suppressed adhesion of THP-1 monocytes to TNF-α-stimulated VSMCs. Ohioensin F reduced TNF-α-induced production of intracellular reactive oxygen species (ROS) and phosphorylation of p38, ERK, JNK and Akt. Finally, ohioensin F inhibited TNF-α-induced CAM mRNA expression and NK-κB translocation.SignificanceThese results suggest a new mechanism of ohioensin F's anti-inflammatory action, owing to the negative regulation of TNF-α-induced adhesion molecule expression, monocyte adhesion and ROS production in vascular smooth muscle cells. Our finding also supports ohioensin F as a potential pharmacological, anti-inflammatory molecule that has a protective effect on the atherosclerotic lesion.  相似文献   
42.
Age-related macular degeneration (AMD) can lead to irreversible central vision loss in the elderly. Although large number of growth factor pathways, including the vascular endothelial growth factor (VEGF), has been implicated in the pathogenesis of AMD, no study has directly assessed the whole proteomic composition in the aqueous humor (AH) among AMD patients. The AH contains proteins secreted from the anterior segment tissue, and these proteins may play an important role in the pathogenesis of AMD. Thus, comparisons between the AH proteomic profiles of AMD patients and non-AMD controls may lead to the verification of novel pathogenic proteins useful as potential clinical biomarkers. In this study, we used discovery-based proteomics and Multiple Reaction Monitoring Mass Spectrometry (MRM-MS) to analyze AH from AMD patients and AH from controls who underwent cataract surgery. A total of 154 proteins with at least two unique peptides were identified in the AH. Of these 154 proteins identified by discovery-based proteomics, 10 AH proteins were novel identifications. The protein composition in the AH was different between AMD patients and non-AMD controls. Subsequently, a systematic MRM-MS assay was performed in seven highly abundant differentially expressed proteins from these groups. Differential expression of three proteins was observed in the AH of AMD patients compared with that of cataract controls (p < 0.0312). Elucidation of the aqueous proteome will establish a foundation for protein function analysis and identify differentially expressed markers associated with AMD. This study demonstrates that integrated proteomic technologies can yield novel biomarkers to detect exudative AMD.  相似文献   
43.
The production of the entomopathogenic and phytotoxic cyclic depsipeptide beauvericin (BEA) was studied in submerged cultures of Fusarium oxysporum KFCC 11363P isolated in Korea. The influences of various factors on mycelia growth and BEA production were examined in both complete and chemically defined culture media. The mycelia growth and BEA production were highest in Fusarium defined medium. The optimal carbon and nitrogen sources for maximizing BEA production were glucose and NaNO3, respectively. The carbon/ nitrogen ratio for maximal production of BEA was investigated using response surface methodology (RSM). Equations derived by differentiation of the RSM model revealed that the production of BEA was maximal when using 108 mM glucose and 25 mM NaNO3.  相似文献   
44.
Hong SP  Shin SK  Lee EH  Kim EO  Ji SI  Chung HJ  Park SN  Yoo W  Folk WR  Kim SO 《Nature protocols》2008,3(9):1476-1484
We describe a matrix-assisted laser desorption/ionization-time of flight (MALDI-TOF) mass spectrometry (MS)-based assay for human papillomavirus (HPV) genotyping--the restriction fragment mass polymorphism (RFMP) assay, which is based on mass measurement of genotype-specific oligonucleotide fragments generated by TypeIIS restriction endonuclease cleavage after recognition sites have been introduced by PCR amplification. The use of a TypeIIS restriction enzyme makes the RFMP assay independent of sequence and applicable to a wide variety of HPV genotypes, because these enzymes have cleavage sites at a fixed distance from their recognition sites. After PCR amplification, samples are subjected to restriction enzyme digestion with FokI and BtsCI and desalting using Oasis purification plates, followed by analysis by MALDI-TOF MS. Overall, the protocol is simple, takes approximately 4-4.5 h and can accurately detect and identify at least 74 different HPV genotypes.  相似文献   
45.
The increasing occurrence of antibiotic‐resistant pathogens is of growing concern, and must be counteracted by alternative antimicrobial treatments. Bacteriophages represent the natural enemies of bacteria. However, the strong immune response following application of phages and rapid clearance from the blood stream are hurdles which need to be overcome. Towards our goal to render phages less immunogenic and prolong blood circulation time, we have chemically modified intact bacteriophages by conjugation of the non‐immunogenic polymer monomethoxy‐polyethylene glycol (mPEG) to virus proteins. As a proof of concept, we have used two different polyvalent and strictly virulent phages of the Myoviridae, representing typical candidates for therapeutical approaches: Felix‐O1 (infects Salmonella) and A511 (infects Listeria). Loss of phage infectivity after PEGylation was found to be proportional to the degree of modification, and could be conveniently controlled by adjusting the PEG concentration. When injected into naïve mice, PEGylated phages showed a strong increase in circulation half‐life, whereas challenge of immunized mice did not reveal a significant difference. Our results suggest that the prolonged half‐life is due to decreased susceptibility to innate immunity as well as avoidance of cellular defence mechanisms. PEGylated viruses elicited significantly reduced levels of T‐helper type 1‐associated cytokine release (IFN‐γ and IL‐6), in both naïve and immunized mice. This is the first study demonstrating that PEGylation can increases survival of infective phage by delaying immune responses, and indicates that this approach can increase efficacy of bacteriophage therapy.  相似文献   
46.
A surface plasmon resonance imaging-based Ni2+-iminodiacetic acid-coated gold chip system was developed to enable specific detection of a hexahistidine-tagged recombinant protein in crude extracts or in column chromatography fractions. This system is especially advantageous for high-throughput analysis of multiple proteins.  相似文献   
47.
E M Ritzi  S Pyo 《Life sciences》1989,44(26):2041-2050
A chemosensitivity assay utilizing small replicate Mm5mt/c1 C3H mammary tumor cell cultures was developed to determine whether changes in viral antigen expression and release into culture fluids could be utilized as an in vitro measure of chemotherapeutic drug effect. The 52,000 MW viral envelope glycoprotein (gp52) of the mouse mammary tumor virus (MMTV) was measured in culture fluids of control and drug-treated cultures while cell density was simultaneously determined by cell staining and OD 664 mu determination. While extracellular gp52 levels and cell density both progressively increased over 72 hours for control cultures, treatments with doxorubicin resulted in dose-dependent declines in both parameters at 24, 48, and 72 hours. Comparison of doxorubicin dosages for 50% reduction (ED50s) in both parameters (0.68uM and 1.1uM) revealed a similar coordinate reduction in both cell density and MMTVgp52. When gp52 levels were further examined as a general measure of effect for a broad spectrum of 6 drugs with differing mechanisms of action, coordinate declines in cell density and MMTVgp52 provided a time and dose-dependent dual measure of effect for each of the drugs tested. Coordinate declines resulted in the same following hierarchy of concentration-dependent drug potency: methotrexate greater than 5-fluorouracil greater than doxorubicin greater than N [phosphonacetyl- L aspartic acid] (PALA) greater than cis-platinum greater than cyclophosphamide. The dual measures of therapeutic effect afforded by this assay argue for its use as an in vitro measure of effect for optimizing drug treatments.  相似文献   
48.
We conducted a comparative anatomical study of the petiole of 16 taxa belonging to the tribe Sorbarieae (Rosaceae) (Adenostoma, 2 spp.; Chamaebatiaria, 1 sp.; Sorbaria, 6 spp., 3 vars., and 1 forma; and Spiraeanthus, 1 sp.) and the related genus Lyonothamnus (1 sp. and 1 ssp.). The distal, medial and proximal regions of petioles were transversely sectioned using conventional embedding and staining methods. Cuticles, crystals, trichomes and pericyclic fiber patterns were observed and studied. Three types of vascular nodal patterns were recognized: Type 1 was seen in Chamaebatiaria, Lyonothamnus, and Spiraeanthus (simple‐trace nodal pattern with slightly curved or U‐shaped vascular bundle); type 2 was found in Adenostoma (multiple‐traces nodal pattern with free vascular bundles); and type 3 was unique to Sorbaria (bundles fused to form a siphonostele nodal pattern). Some petiolar anatomical characteristics (e.g. cuticles, crystals, trichomes, vascular nodal pattern, and pericyclic fiber patterns) were found to provide useful information for taxonomic studies within Sorbarieae. On the basis of these characteristics, a dichotomous key for identification at the generic/specific level is provided. We also report a structural change in the vascular bundles from the stem‐leaf transitional zone to the leaf medial zone.  相似文献   
49.
The hemiascomycetes yeast Yarrowia lipolytica is a dimorphic yeast with alternating yeast and mycelia forms. Bioinformatic analysis revealed the presence of three putative chitinase genes, YlCTS1, YlCTS2, and YlCTS3, in the Y. lipolytica genome. Here, we demonstrated that the protein of YlCTS1 (YlCts1p), which contains an N-terminal secretion signal peptide, a long C-terminal Ser/Thr-rich domain, and a chitin-binding domain, is a homologue to Saccharomyces cerevisiae chitinase 1 (ScCts1p). Deletion of YlCTS1 remarkably reduced extracellular endochitinase activity in the culture supernatant of Y. lipolytica and enhanced cell aggregation, suggesting a role of YlCts1p in cell separation as ScCts1p does in S. cerevisiae. However, loss of YlCts1p function did not affect hyphal formation induced by fetal bovine serum addition. The mass of YlCts1p was dramatically decreased by jack bean α-mannosidase digestion but not by PNGase F treatment, indicating that YlCts1p is modified only by O-mannosylation without N-glycosylation. Moreover, the O-glycan profile of YlCts1p was identical to that of total cell wall mannoproteins, supporting the notion that YlCts1p can be used as a good model for studying O-glycosylation in this dimorphic yeast.  相似文献   
50.
Jung NH  Kim HP  Kim BR  Cha SH  Kim GA  Ha H  Na YE  Cha YN 《IUBMB life》2003,55(9):525-532
The interaction of heme oxygenase-1 (HO-1) and caveolin in the cultured mouse mesangial cells (MMC) was investigated. In normal MMCs, high levels of caveolin-2 and low level of caveolin-1 at mRNA and protein level were observed without any detectable expression of caveolin-3. Upon treating the MMCs either with cadmium (Cd) or spermine NONOate (SPER/NO), expression of HO-1 mRNA and protein was increased. Caveolae rich membranous fractions from the MMCs treated with Cd or SPER/NO contained both HO-1 and caveolin-1 or caveolin-2. The experiments of immuno-precipitation showed complex formation between the HO-1 and caveolin-1 or caveolin-2 in the Cd treated MMCs. Confocal microscopic results also support co-localization of HO-1 and caveolin-1 or caveolin-2 at the plasma membrane. Co-localization of caveolins with HO-1 in caveolae suggested that caveolin could also play an important role in regulating the function of HO-1.  相似文献   
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