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81.
Wei L Sandbulte MR Thomas PG Webby RJ Homayouni R Pfeffer LM 《The Journal of biological chemistry》2006,281(17):11678-11684
Interferons (IFNs) are antiviral cytokines that selectively regulate gene expression through several signaling pathways including nuclear factor kappaB(NFkappaB). To investigate the specific role of NFkappaB in IFN signaling, we performed gene expression profiling after IFN treatment of embryonic fibroblasts derived from normal mice or mice with targeted deletion of NFkappaB p50 and p65 genes. Interestingly, several antiviral and immunomodulatory genes were induced higher by IFN in NFkappaB knock-out cells. Chromatin immunoprecipitation experiments demonstrated that NFkappaB was basally bound to the promoters of these genes, while IFN treatment resulted in the recruitment of STAT1 and STAT2 to these promoters. However, in NFkappaB knock-out cells IFN induced STAT binding as well as the binding of the IFN regulatory factor-1 (IRF1) to the IFN-stimulated gene (ISG) promoters. IRF1 binding closely correlated with enhanced gene induction. Moreover, NFkappaB suppressed both antiviral and immunomodulatory actions of IFN against influenza virus. Our results identify a novel negative regulatory role of NFkappaB in IFN-induced gene expression and biological activities and suggest that modulating NFkappaB activity may provide a new avenue for enhancing the therapeutic effectiveness of IFN. 相似文献
82.
Functional analysis of Hes-1 in preadipocytes 总被引:3,自引:0,他引:3
83.
84.
M. Elizabeth Sublette Matthew S. Milak Joseph R. Hibbeln Peter J. Freed Maria A. Oquendo Kevin M. Malone Ramin V. Parsey J. John Mann 《Prostaglandins, leukotrienes, and essential fatty acids》2009,80(1):57-64
Deficiencies in polyunsaturated essential fatty acids (PUFA) are implicated in mood disorders, although mechanisms of action and regional specificity in the brain are unknown. We hypothesized that plasma phospholipid PUFA levels are correlated with regionally specific relative cerebral metabolic rates of glucose (rCMRglu). Medication-free depressed subjects (N=29) were studied using [18F]-fluoro-2-deoxyglucose positron emission tomography. Docosahexaenoic acid (22:6n-3), arachidonic acid (20:4n-6), and eicosapentaenoic acid (20:5n-3) were assessed as a percentage of total phospholipid PUFA (DHA%, AA%, and EPA%, respectively). DHA% and AA% correlated positively with rCMRglu in temporoparietal cortex. In addition, DHA% correlated negatively with rCMRglu in prefrontal cortex and anterior cingulate. No correlations were seen with EPA%. Thus, under conditions of low plasma DHA, rCMRglu was higher in temporoparietal cortex and lower in anterior cingulate/prefrontal cortex. Opposing effects of DHA on these regions is a hypothesis that could be addressed in future prospective studies with n-3 supplementation. This pilot study is the first to demonstrate fatty acid and regionally specific correlations in the brain between plasma PUFA and rCMRglu in humans. 相似文献
85.
Zahra B. Mokhtari-Hosseini Ebrahim Vasheghani-Farahani Ali Heidarzadeh-Vazifekhoran S. Abbas Shojaosadati Ramin Karimzadeh Kianoush Khosravi Darani 《Bioresource technology》2009,100(8):2436-2443
Media components were optimized by statistical design for cell growth and PHB production of Methylobacterium extorquens DSMZ 1340. Four important components of growth media were optimized by central composite design. The growth increased from an OD = 1.35 for Choi medium as control to an OD = 2.15 for optimal medium. Then media components for PHB production were optimized. Optimization of five important factors was conducted by response surface method. The optimal composition of PHB production medium was found to be at 7.8 (g/L) Na2HPO4 · 12H2O, and surprisingly at zero concentration of (NH4)2SO4, KH2PO4, MgSO4 and MnSO4. The PHB production was found to be 2.95 (g/L) at this medium. RSM results indicated that a deficiency of nitrogen and magnesium is crucial for PHB accumulation in this microorganism. Also, PHB production was carried out in a 5 L fermentor at the optimum condition which resulted in 9.5 g/L PHB and 15.4 g/L cell dry weight with 62.3% polymer content. 相似文献
86.
Katayoun?JavidniaEmail author Farzaneh?Aram Mahmood?Solouki Ahmad?Reza Mehdiopour Maryam?Gholami Ramin?Miri 《Annals of microbiology》2009,59(2):349
High commercial value compounds can be obtained through the microbial biotransformation of monoterpenes. Some of these monoterpenic substances are not expensive and produced in a variety of plant species. Biotransformation of some monoterpene hydrocarbons such as α-pinene, β-pinene, myrcene and p-cymene by 7 strain bacteria and 2 strain fungi was investigated. It was observed that some of microorganisms transformed monoterpenes to oxygenated monoterpenes in a good yield which among themStaphylococcus epidermidis showed higher yields. 相似文献
87.
Ramin Farzaneh-Far Jue Lin Elissa Epel Kyle Lapham Elizabeth Blackburn Mary A. Whooley 《PloS one》2010,5(1)
Background
Leukocyte telomere length, an emerging marker of biological age, has been shown to predict cardiovascular morbidity and mortality. However, the natural history of telomere length in patients with coronary artery disease has not been studied. We sought to investigate the longitudinal trajectory of telomere length, and to identify the independent predictors of telomere shortening, in persons with coronary artery disease.Methodology/Principal Findings
In a prospective cohort study of 608 individuals with stable coronary artery disease, we measured leukocyte telomere length at baseline, and again after five years of follow-up. We used multivariable linear and logistic regression models to identify the independent predictors of leukocyte telomere trajectory. Baseline and follow-up telomere lengths were normally distributed. Mean telomere length decreased by 42 base pairs per year (p<0.001). Three distinct telomere trajectories were observed: shortening in 45%, maintenance in 32%, and lengthening in 23% of participants. The most powerful predictor of telomere shortening was baseline telomere length (OR per SD increase = 7.6; 95% CI 5.5, 10.6). Other independent predictors of telomere shortening were age (OR per 10 years = 1.6; 95% CI 1.3, 2.1), male sex (OR = 2.4; 95% CI 1.3, 4.7), and waist-to-hip ratio (OR per 0.1 increase = 1.4; 95% CI 1.0, 2.0).Conclusions/Significance
Leukocyte telomere length may increase as well as decrease in persons with coronary artery disease. Telomere length trajectory is powerfully influenced by baseline telomere length, possibly suggesting negative feedback regulation. Age, male sex, and abdominal obesity independently predict telomere shortening. The mechanisms and reversibility of telomeric aging in cardiovascular disease deserve further study. 相似文献88.
Histone methylation is involved in the regulation of many cellular processes. In the past 2 years, several histone demethylases including BHC110/LSD1 have been characterized. BHC110, the first known histone lysine demethylase, removes methyl groups from methylated histone H3 lysine 4 and has been found in many multi-protein complexes. Using one-step affinity purification, we have isolated enzymatically active BHC110-containing complexes. Here, we detail the methods used for the isolation and characterization of these histone demethylase complexes from a human stable cell line. 相似文献
89.
We describe a boy with chronic abdominal pain, nausea and vomiting, and weight loss. The imaging was compatible with Takayasu's arteritis. Chronic mesenteric ischemia was the etiology of the patient's symptoms. 相似文献
90.