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971.
Jin G Jeon HS Lee EB Kang HG Yoo SS Lee SY Lee JH Cha SI Park TI Kim CH Jheon SH Park JY 《Journal of Korean medical science》2012,27(2):228-230
A fusion gene between echinoderm microtubule-associated protein-like 4 (EML4) and the anaplastic lymphoma kinase (ALK) has been identified in non-small cell lung cancers (NSCLCs). Although a few studies have evaluated EML4-ALK fusion genes in Korean NSCLCs, the prevalence of different EML4-ALK fusion variants has yet to be clearly assessed. Herein, we have examined the profiles of EML4-ALK fusion gene variants in Korean patients of NSCLCs. EML4-ALK fusion genes have been detected in 10 (6.0%) of 167 patients of NSCLCs and in 9 (7.4%) of 121 patients of adenocarcinoma. Of the 10 patients with fusion genes identified, 8 (80%) were E13;A20 (variant 1) and 2 (20%) were E6;A20, with an additional 33-bp sequence derived from intron 6 of EML4 (variant 3b). These results indicate that the profiles of EML4-ALK fusion gene variants in Korean patients of NSCLC may differ from those in other ethnic populations. Herein, we describe for the first time the profiles of EML4-ALK fusion variants of Korean patients with NSCLCs. 相似文献
972.
Copy number variation has been associated with various autoimmune diseases. We investigated the copy number (CN) of the DEFA1 gene encoding α-defensin-1 in samples from Korean individuals with Behcet''s disease (BD) compared to healthy controls (HC). We recruited 55 BD patients and 35 HC. A duplex Taqman® real-time PCR assay was used to assess CN. Most samples (31.1%) had a CN of 5 with a mean CN of 5.4 ± 0.2. There was no significant difference in the CN of the DEFA1 gene between BD patients and HC. A high DEFA1 gene CN was significantly associated with intestinal involvement in BD patients. Variable DEFA1 gene CNs were observed in both BD patients and HC and a high DEFA1 gene CN may be associated with susceptibility to intestinal involvement in BD. 相似文献
973.
974.
Park SJ Lee KS Kim SR Chae HJ Yoo WH Kim DI Jeon MS Lee YC 《Inflammation research》2012,61(10):1069-1083
Background
Occupational asthma is characterized by airway inflammation and hyperresponsiveness associated with increased vascular permeability. AMP-activated protein kinase (AMPK) has been suggested to be a novel signaling molecule modulating inflammatory responses.Objective
We sought to evaluate the involvement of AMPK in pathogenesis of occupational asthma and more specifically investigate the effect and molecular mechanisms of AMPK activation in regulating vascular permeability.Methods
The mechanisms of action and therapeutic potential of an AMPK activator, 5-aminoimidazole-4-carboxamide-1-β-d-ribofuranoside (AICAR) were tested in a murine model of toluene diisocyanate (TDI)-induced asthma.Results
AICAR attenuated airway inflammation and hyperresponsiveness increased by TDI inhalation. Moreover, TDI-induced increases in levels of hypoxia-inducible factor (HIF)-1α, HIF-2α, vascular endothelial growth factor A (VEGFA), and plasma exudation were substantially decreased by treatment with AICAR. Our results also showed that VEGFA expression was remarkably reduced by inhibition of HIF-1α and HIF-2α with 2-methoxyestradiol (2ME2) and that an inhibitor of VEGFA activity, CBO-P11 as well as 2ME2 significantly suppressed vascular permeability, airway infiltration of inflammatory cells, and airway hyperresponsiveness induced by TDI. In addition, AICAR reduced reactive oxygen species (ROS) generation and levels of malondialdehyde and T-helper type 2 cytokines (IL-4, IL-5, and IL-13), while this agent enhanced expression of an anti-inflammatory cytokine, IL-10.Conclusions
These results suggest that AMPK activation ameliorates airway inflammatory responses by reducing vascular permeability via HIF/VEGFA pathway as well as by inhibiting ROS production and thus may be a possible therapeutic strategy for TDI-induced asthma and other airway inflammatory diseases. 相似文献975.
976.
A new strategy to develop an effective vaccine is essential to control food-borne Salmonella enterica serovar Enteritidis infections. Bacterial ghosts (BGs), which are nonliving, Gram-negative bacterial cell envelopes, are generated by expulsion of the cytoplasmic contents from bacterial cells through controlled expression using the modified cI857/λ P(R)/gene E expression system. In the present study, the pJHL99 lysis plasmid carrying the mutated lambda pR37-cI857 repressor and PhiX174 lysis gene E was constructed and transformed in S. Enteritidis to produce a BG. Temperature induction of the lysis gene cassette at 42°C revealed quantitative killing of S. Enteritidis. The S. Enteritidis ghost was characterized using scanning and transmission electron microscopy to visualize the transmembrane tunnel structure and loss of cytoplasmic materials, respectively. The efficacy of the BG as a vaccine candidate was evaluated in a chicken model using 60 10-day-old chickens, which were divided into four groups (n = 15), A, B, C, and D. Group A was designated as the nonimmunized control group, whereas the birds in groups B, C, and D were immunized via the intramuscular, subcutaneous, and oral routes, respectively. The chickens from all immunized groups showed significant increases in plasma IgG and intestinal secretory IgA levels. The lymphocyte proliferation response and CD3(+) CD4(+) and CD3(+) CD8(+) T cell subpopulations were also significantly increased in all immunized groups. The data indicate that both humoral and cell-mediated immune responses are robustly stimulated. Based on an examination of the protection efficacy measured by observations of gross lesions in the organs and bacterial recovery, the candidate vaccine can provide efficient protection against virulent challenge. 相似文献
977.
Park HY Hahm CR Jeon K Koh WJ Suh GY Chung MP Kim H Kwon OJ Um SW 《Yonsei medical journal》2012,53(2):369-376
Purpose
Vascular endothelial growth factor (VEGF) and angiopoietin-2 (Ang-2) are major mediators of angiogenesis and are induced by tissue inflammation and hypoxia. The purpose of this study was to investigate whether serum VEGF and Ang-2 are associated with the presence of hemoptysis and the extent of systemic inflammation in patients with inflammatory lung diseases.Materials and Methods
We prospectively enrolled 52 patients with inflammatory lung disease between June 2008 and October 2009.Results
The median values of VEGF and Ang-2 were 436 pg/mL and 2383 pg/mL, respectively. There was a significant positive correlation between serum Ang-2 and VEGF levels. VEGF levels were not significantly different according to the presence of hemoptysis. C-reactive protein (CRP) and Ang-2 level were significantly higher in patients without hemoptysis (n=26) than in those with hemoptysis (n=26; p<0.001 and p<0.001, respectively). CRP and arterial oxygen tension (PaO2) were significantly correlated with both serum VEGF (p=0.032 and p=0.016, respectively) and Ang-2 levels (p<0.001 and p=0.041, respectively), after adjusting for other factors. Age and the absence of hemoptysis were factors correlated with serum Ang-2 levelsConclusion
Our study suggests that serum VEGF and Ang-2 levels are associated with PaO2 and the severity of inflammation rather than the presence of hemoptysis in patients with inflammatory lung diseases. Thus, hemoptysis may not be mediated by increased serum levels of VEGF and Ang-2 in patients with inflammatory lung diseases, and further studies are required to determine the mechanisms of hemoptysis. 相似文献978.
Jeon EJ Yoon BY Lim JY Oh HJ Park HS Park MJ Lim MA Park MK Kim KW Cho ML Cho SG 《Autoimmunity》2012,45(6):460-469
Maintaining an appropriate balance between subsets of CD4(+) helper T cells and T regulatory cells (Tregs) is a critical process in immune homeostasis and a protective mechanism against autoimmunity and inflammation. To identify the role of vitamin A-related compounds, we investigated the regulation of interleukin (IL)-17-producing helper T cells (Th17 cells) and Tregs treated with all-trans-retinal (retinal). CD4(+)T cells or total cells from the spleens of C57BL/6 mice were stimulated under Treg-polarizing (anti-CD3/CD28 and TGF-β) or Th17-polarizing (anti-CD3/CD28, TGF-β, and IL-6) conditions in the presence or absence of retinal. To analyze their suppressive abilities, retinal-induced Tregs or TGF-β-induced Tregs were co-cultured with responder T cells. Collagen-induced arthritis (CIA) was established in interferon (IFN)-γ knockout mice. On day 13, retinal-induced Tregs were adoptively transferred to mice with established CIA after second immunizations. Compared with TGF-β-induced Treg cells, retinal-induced Tregs showed increased Foxp3 expression and mediated stronger suppressive activity. Under Th17-polarizing conditions, retinal inhibited the production of IL-17 and increased the expression of Foxp3.Retinal-induced Tregs showed therapeutic effects in IFN-γ knockout CIA mice. Thus, we demonstrated that retinal reciprocally regulates Foxp3(+) Tregs and Th17 cells. These findings suggest that retinal, a vitamin A metabolite, can regulate the balance between pro- and anti-inflammatory immunity. A better understanding of the manipulation of Foxp3 and Tregs may enable the application of this tremendous therapeutic potential in various autoimmune diseases. 相似文献
979.
980.
Acinetobacter oleivorans DR1 lacks an upper pathway for naphthalene degradation and cannot grow using naphthalene as sole carbon source; however, it is capable of growing under naphthalene-amended conditions in the presence of naphthalene-degrading Pseudomonas sp. AS1. 1H-NMR spectroscopy, high-performance liquid chromatography and gene expression analyses showed that salicylate is a major secreted metabolic intermediate during naphthalene degradation by strain AS1 and that, in turn, it supports the growth of strain DR1. Interspecies biofilm formation, monitored using confocal laser scanning microscopy and microtiter assays, demonstrated that biofilm formation by strain AS1 increased dramatically in the presence of strain DR1 because of the exopolysaccharides generated by the latter. Furthermore, the metabolic commensal interaction of the two strains altered the initial attachment behavior of strain DR1 during biofilm formation. When this strain was cultivated alone under naphthalene-amended conditions, the cells immediately attached to the surface, probably due to the absence of usable substrates, whereas similar behavior was not observed in the mixed culture. This interspecies cell-cell interaction became more complex due to quenching of the quorum-sensing signal of strain DR1 by strain AS1. These complex metabolic and physiological interactions observed in mixed cultures suggest that interspecies interaction is more complicated than previously surmised. 相似文献