Majority of cancer cells upregulate co-inhibitory molecule B7-H1 which confers resistance to anti-tumor immunity, allowing cancers to escape from host immune surveillance. We addressed the molecular mechanism underlying the regulation of cancer-associated B7-H1 expression in response to interferon-c (IFN-c). Using promoter constructs in luciferase assay, the region between 202 and 320 bp from the translational start site is responsible for B7-H1 expression. Electrophoretic mobility shift assay, site-directed mutagenesis and knockdown experiment using siRNA revealed that interferon regulatory factor-1 (IRF-1) is primarily responsible for the constitutive B7-H1 expression as well as for the IFN-c-mediated B7-H1 upregulation in a human lung cancer cell line A549. Additionally, AG490, a Janus activated kinase/signal transducer and activator of transcription inhibitor, greatly abolished the responsiveness of A549 cells to IFN-c by reducing the IRF-1 transcription. Our findings support a critical role of IRF-1 in the regulation of constitutive and IFN-c-induced expression of B7-H1 in cancer cells.

No abstract

The most widespread dietary problem in the world is mineral deficiency. We used the nicotianamine synthase (NAS) gene to increase mineral contents in rice grains. Nicotianamine (NA) is a chelator of metals and a key component of metal homeostasis. We isolated activation-tagged mutant lines in which expression of a rice NAS gene, OsNAS3, was increased by introducing 35S enhancer elements. Shoots and roots of the OsNAS3 activationtagged plants (OsNAS3-D1) accumulated more Fe and Zn. Seeds from our OsNAS3-D1 plants grown on a paddy field contained elevated amounts of Fe (2.9-fold), Zn (2.2-fold), and Cu (1.7-fold). The NA level was increased 9.6-fold in OsNAS3-D1 seeds. Analysis by size exclusion chromatography coupled with inductively coupled plasma mass spectroscopy showed that WT and Os-NAS3-D1 seeds contained equal amounts of Fe bound to IP6, whereas OsNAS3-D1 had 7-fold more Fe bound to a low molecular mass, which was likely NA. Furthermore, this activation led to increased tolerance to Fe and Zn deficiencies and to excess metal (Zn, Cu, and Ni) toxicities. In contrast, disruption of OsNAS3 caused an opposite phenotype. To test the bioavailability of Fe, we fed anemic mice with either engineered or WT seeds for 4 weeks and measured their concentrations of hemoglobin and hematocrit. Mice fed with engineered seeds recovered to normal levels of hemoglobin and hematocrit within 2 weeks, whereas those that ate WT seeds remained anemic. Our results suggest that an increase in bioavailable mineral content in rice grains can be achieved by enhancing NAS expression. activation tagging ͉ bioavailability ͉ hemoglobin ͉ metal homeostasis

The capacity of cells to maintain homeostasis during oxidative stress resides in activation or induction of protective enzymes. Nuclear-factor-E2-related factor (Nrf)-2 as a member of bZIP transcription factors is expressed in a variety of tissues. Transcriptional activation of antioxidant genes through an antioxidant response element (ARE) is largely dependent upon Nrf2. The genes that contain a functional ARE include those encoding GSTA1, GSTA2, NAD(P)H:quinone reductase, and gamma-glutamylcysteine synthetase heavy and light subunits that play a role in defense against oxidative stress. Previously, we showed that phosphatidylinositol 3-kinase (PI3-kinase) controls nuclear translocation of Nrf2 in response to oxidative stress, which involves rearrangement of actin microfilaments. Now, we report that PI3-kinase is responsible for the rise of cellular Ca(2+), which is requisite for nuclear translocation of Nrf2. Immunocytochemistry and subcellular fractionation analyses revealed that Nrf2 relocated from the cytoplasm to the plasma membrane prior to its nuclear translocation. We further found that CCAAT/enhancer binding protein-beta (C/EBPbeta), peroxisome proliferatoractivated receptor-gamma (PPARgamma), and retinoid X receptor (RXR) heterodimer serve as the activating transcription factors for the phase II gene induction. Hence, PI3-kinase-mediated Nrf2 activation in combination with activating PPARgamma-RXR and C/EBPbeta contributes to antioxidant phase II enzyme induction via coordinate gene transactivation.

Expression of phase II detoxifying genes is regulated by NF-E2-related factor 2 (Nrf2)-mediated antioxidant response element (ARE) activation. We showed previously that phosphatidylinositol 3 (PI3)-kinase plays an essential role in AREmediated rGSTA2 induction by oxidative stress. In view of the fact that the signaling pathway of PI3-kinase controls microfilaments and translocation of actin-associated proteins, the current study was designed to investigate the PI3-kinase-mediated nuclear translocation of Nrf2 and the interaction of Nrf2 with actin. tert-Butylhydroquinone (t-BHQ) caused Nrf2 to translocate into the nucleus in H4IIE cells, which was prevented by pretreatment of the cells with PI3-kinase inhibitors (wortmannin/LY294002). t-BHQ relocalized Nrf2 in concert with changes in actin microfilament architecture, as visualized by superposition of immunochemically stained Nrf2 and fluorescent phalloidin-stained actin. Furthermore, t-BHQ increased the level of nuclear actin, coimmunoprecipitated with Nrf2, which returned to that of control by pretreatment of the cells with PI3-kinase inhibitors. Cytochalasin B, an actin disruptor, alone stimulated actin-mediated nuclear translocation of Nrf2 and induced rGSTA2. In contrast, phalloidin, an agent that prevents actin filaments from depolymerization, inhibited Nrf2 translocation and rGSTA2 induction by t-BHQ. Subcellular fractionation and immunoblot analyses allowed us to detect both 57-and 100-kDa Nrf2. Immunoblot and immunoprecipitation assays showed that the 100-kDa protein comprised both Nrf2 and actin. The present study demonstrates that the PI3-kinase signaling pathway regulates rearrangement of actin microfilaments in response to oxidative stress and that depolymerization of actin causes a complex of Nrf2 bound with actin to translocate into nucleus.

Our results suggest that botulinum toxin injection reduced the number of bruxism events, most likely mediated its effect through a decrease in muscle activity rather than the central nervous system. We controlled for placebo effects by randomizing the interventions between groups, obtaining subjective and objective outcome measures, using the temporalis muscle as a control, and collecting data at three postinjection times. Our controlled study supports the use of botulinum toxin injection as an effective treatment for nocturnal bruxism.

ABSTRACT:The electrospinning of polyglycolide (PGA), poly(l-lactide) (PLA), and poly(lactide-co-glycolide) (PLGA; l-lactide/glycolide ϭ 50/50) was performed with chloroform or 1,1,1,3,3,3-hexafluoro-2-propanol (HFIP) as a spinning solvent to fabricate their nanofiber matrices. The morphology of the electrospun PGA, PLA, and PLGA nanofibers was investigated with scanning electron microscopy (SEM). The PLGA nanofibers, electrospun with a nonpolar chloroform solvent, had a relatively large average diameter (760 nm), and it had a relatively broad distribution in the range of 200 -1800 nm. On the other hand, the PGA and PLA fibers, electrospun with a polar HFIP solvent, had a small average diameter (ϳ300 nm) with a narrow distribution. This difference in the fiber diameters may be associated with the polarity of the solvent. Also, the in vitro degradation of PGA, PLA, and PLGA nanofiber matrices was examined in phosphate buffer solutions (pH 7.4) at 37°C. The degradation rates of the nanofiber matrices were fast, in the order of PGA Ͼ PLGA ӷ PLA. Structural and morphological changes during in vitro degradation were investigated with differential scanning calorimetry and wide-angle X-ray diffraction. For the PGA matrix, a significant increase in the crystallinity during the early stage was detected, as well as a gradual decrease during the later period, and this indicated that preferential hydrolytic degradation in the amorphous regions occurred with cleavage-induced crystallization, followed by further degradation in the crystalline region.

PurposeLimited data is available on the prevalence and risk factors of acute and chronic urticaria in children. Our purpose was to determine the prevalence and identify the risk factors of acute and chronic urticaria in Korean children.MethodsThis population-based study examined 4,076 children (age 4 to 13 years) who were enrolled in the 2015 prospective Seongnam Atopy Project (SAP 2015) in Korea. The parents completed an urticaria questionnaire that included questions regarding the duration, severity, and triggering factors of urticaria. Blood sampling (n=464) was performed to measure vitamin D, total eosinophil count (TEC), and total IgE levels, and skin prick tests (n=503) were done.ResultsThe prevalences of the life-time, acute, and chronic urticaria were 22.5%, 13.9%, and 1.8% (chronic continuous urticaria, 0.7%; and chronic recurrent urticaria, 1.1%), respectively. Acute urticaria was significantly associated with allergic diseases and parental history of allergy (P<0.001), but chronic urticaria was not associated with these clinical factors. There was no significant difference in the 25-hydroxyvitamin D level between subjects with chronic urticaria and controls (P=0.124). Chronic continuous urticaria was associated with living in a new residence (aOR=2.38, 95% CI=1.02-5.54, P=0.044) and belonging to a family with a high income (aOR=4.24, 95% CI=1.24-14.56, P=0.022).ConclusionsA total of 1.8% of children were found to have chronic urticaria. Living in a new residence and belonging to a family with a high income increased the risk of chronic continuous urticaria.