Isolation and characterization of mutations affecting expression of the Δ9- fatty acid desaturase gene, OLE1, in Saccharomyces cerevisiae

AbstractExpression of the Δ9- fatty acid desaturase gene, OLE1, of Saccharomyces cerevisiae is negatively regulated transcriptionally and post-transcriptionally by unsaturated fatty acids. In order to isolate mutants exhibiting irregulation of OLE1 expression, we constructed an OLE1p–PHO5 fusion gene as a reporter consisting of the PHO5 gene encoding repressible acid phosphatase (rAPase) under the control of the OLE1 promoter (OLE1p). By EMS mutagenesis, we isolated three classes of mutants, pfo1, pfo2 and pfo3 (positive regulatory factor for OLE1) mutants, which show decreased rAPase activity under derepression conditions (absence of oleic acid). Analysis of the transcription of OLE1 in these pfo mutants revealed that pfo1 and pfo3 mutants have a defect in the regulation of OLE1 expression at the transcriptional level while pfo2 mutants were suggested to have a mutation affecting OLE1 expression at a post-transcriptional step. In addition, four other classes of mutants, nfo1, nfo2, nfo3 and nfo4 (negative factor for OLE1) mutants that have mutations causing strong expression of the OLE1p–PHO5 fusion gene under repression conditions (presence of oleic acid), were isolated. Results of Northern analysis of OLE1 as well as OLE1p-PHO5 transcripts in nfo mutants suggested that these mutations occurred in genes encoding global repressors. We also demonstrated that TUP1 and SSN6 gene products are required for full repression of OLE1 gene expression, by showing that either tup1 or ssn6 mutations greatly increase the level of the OLE1 transcript

Requisite role of vasohibin‐2 in spontaneous gastric cancer formation and accumulation of cancer‐associated fibroblasts

The vasohibin (VASH) family consists of two genes, VASH1 and VASH2. VASH1 is mainly expressed in vascular endothelial cells and suppresses angiogenesis in an autocrine manner, whereas VASH2 is mainly expressed in cancer cells and exhibits pro‐angiogenic activity. Employing adenomatous polyposis coli gene mutant mice, we recently reported on the role of Vash2 in the spontaneous formation of intestinal tumors. In this study, we used K19‐Wnt1/C2mE (Gan) mice and examined the role of Vash2 in spontaneous gastric cancer formation. Gan mice spontaneously develop gastric tumors by activation of Wnt and prostaglandin E2 signaling pathways in gastric mucosa after 30 weeks of age. Expression of Vash2 mRNA was significantly increased in gastric tumor tissues compared with normal stomach tissues. When Gan mice were crossed with the Vash2‐deficient (Vash2 LacZ/LacZ) strain, gastric cancer formation was significantly suppressed in Vash2 LacZ/LacZ Gan mice. Normal composition of gastric mucosa was partially maintained in Vash2 LacZ/LacZ Gan mice. Knockout of Vash2 caused minimal reduction of tumor angiogenesis but a significant decrease in cancer‐associated fibroblasts (CAF) in tumor stroma. DNA microarray analysis and real‐time RT‐PCR showed that mRNA levels of epiregulin (Ereg) and interleukin‐11 (Il11) were significantly downregulated in gastric tumors of Vash2 LacZ/LacZ Gan mice. Furthermore, conditioned medium of gastric cancer cells stimulated migration of and α‐smooth muscle actin expression in fibroblasts, whereas conditioned medium of VASH2 knockdown cells attenuated these effects in vitro. These results suggest that VASH2 plays an important role in gastric tumor progression via the accumulation of CAF accompanying upregulation of EREG and IL‐11 expression

IL-7 promotes long-term in vitro survival of unique long-lived memory subset generated from mucosal effector memory CD4(+) T cells in chronic colitis mice

Colitogenic memory CD4(+) T cells are important in the pathogenesis of inflammatory bowel disease (IBD). Although memory stem cells with high survival and self-renewal capacity were recently identified in both mice and humans, it is unclear whether a similar subset is present in chronic colitis mice. We sought to identify and purify a long-lived subset of colitogenic memory CD4(+) T cells, which may be targets for treatment of IBD. A long-lived subset of colitogenic memory CD4(+) T cells was purified using a long-term culture system. The characteristics of these cells were assessed. Interleukin (IL)-7 promoted the in vitro survival for >8 weeks of lamina propria (LP) CD4(+) T cells from colitic SOD mice previously injected with CD4(+)CD45RB(high) T cells. These cells were in a quiescent state and divided a maximum of 5 times in 4 weeks. LP CD4(+) T cells expressed higher levels of Bcl-2, integrin-alpha 4 beta 7, CXCR3 and CD25 after than before culture, as well as secreting high concentrations of IL-2 and low concentrations of IFN-gamma and IL-17 in response to intestinal bacterial antigens. LP CD4(+) T cells from colitic mice cultured with IL-7 for 8 weeks induced more severe colitis than LP CD4(+) T cells cultured for 4 weeks. We developed a novel culture system to purify a long-lived, highly pathogenic memory subset from activated LP CD4(+) T cells. IL-7 promoted long-term in vitro survival of this subset in a quiescent state. This subset will be a novel, effective target for the treatment of IBD

Quantification of Warming Climate-Induced Changes in Terrestrial Arctic River Ice Thickness and Phenology

A land process model [the coupled hydrological and biogeochemical model (CHANGE)] is used to quantitatively assess changes in the ice phenology, thickness, and volume of terrestrial Arctic rivers from 1979 to 2009. The CHANGE model was coupled with a river routing and discharge model enabling explicit representation of river ice and water temperature dynamics. Model-simulated river ice phenological dates and thickness were generally consistent with in situ river ice data and landscape freeze–thaw (FT) satellite observations. Climate data indicated an increasing trend in winter surface air temperature (SAT) over the pan-Arctic during the study period. Nevertheless, the river ice thickness simulations exhibited a thickening regional trend independent of SAT warming, and associated with less insulation and cooling of underlying river ice by thinning snow cover. Deeper snow depth (SND) combined with SAT warming decreased simulated ice thickness, especially for Siberian rivers, where ice thickness is more strongly correlated with SND than SAT. Overall, the Arctic river ice simulations indicated regional trends toward later fall freezeup, earlier spring breakup, and consequently a longer annual ice-free period. The simulated ice phenological dates were significantly correlated with seasonal SAT warming. It is found that SND is an important factor for winter river ice growth, while ice phenological timing is dominated by seasonal SAT. The mean total Arctic river ice volume simulated from CHANGE was 54.1 km3 based on the annual maximum ice thickness in individual grid cells, while river ice volume for the pan-Arctic rivers decreased by 2.82 km3 (0.5%) over the 1979–2009 record. Arctic river ice is shrinking as a consequence of regional climate warming and coincident with other cryospheric components, including permafrost, glaciers, and sea ice

Ge Interface Engineering with Ozone-oxidation for Low Interface State Density

Passivation of Ge has been a critical issue for Ge MOS applications in future technology nodes. In this letter, we introduce ozone-oxidation to engineer Ge/insulator interface. Interface states (D{sub it}) values across the bandgap and close to conduction bandedge were extracted using conductance technique at low temperatures. D{sub it} dependency on growth conditions was studied. Minimum D{sub it} of 3 x 10{sup 11} cm{sup -2} V{sup -1} was demonstrated. Physical quality of the interface was investigated through Ge 3d spectra measurements. We found that the interface and D{sub it} is strongly affected by the distribution of oxidation states and quality of the suboxide

Plaque REgression with Cholesterol absorption Inhibitor or Synthesis inhibitor Evaluated by IntraVascular UltraSound (PRECISE-IVUS Trial): Study protocol for a randomized controlled trial

AbstractBackgroundAlthough the positive association between achieved low-density lipoprotein cholesterol (LDL-C) level and the risk of coronary artery disease (CAD) has been confirmed by randomized studies with statins, many patients remain at high residual risk of events suggesting the necessity of novel pharmacologic strategies. The combination of ezetimibe/statin produces greater reductions in LDL-C compared to statin monotherapy.PurposeThe Plaque REgression with Cholesterol absorption Inhibitor or Synthesis inhibitor Evaluated by IntraVascular UltraSound (PRECISE-IVUS) trial was aimed at evaluating the effects of ezetimibe addition to atorvastatin, compared with atorvastatin monotherapy, on coronary plaque regression and change in lipid profile in patients with CAD.MethodsThe study is a prospective, randomized, controlled, multicenter study. The eligible patients undergoing IVUS-guided percutaneous coronary intervention will be randomly assigned to receive either atorvastatin alone or atorvastatin plus ezetimibe (10mg) daily using a web-based randomization software. The dosage of atorvastatin will be increased by titration within the usual dose range with a treatment goal of lowering LDL-C below 70mg/dL based on consecutive measures of LDL-C at follow-up visits. IVUS will be performed at baseline and 9–12 months follow-up time point at participating cardiovascular centers. The primary endpoint will be the nominal change in percent coronary atheroma volume measured by volumetric IVUS analysis.ConclusionPRECISE-IVUS will assess whether the efficacy of combination of ezetimibe/atorvastatin is noninferior to atorvastatin monotherapy for coronary plaque reduction, and will translate into increased clinical benefit of dual lipid-lowering strategy in a Japanese population

Pattern of disease progression during third-line or later chemotherapy with nivolumab associated with poor prognosis in advanced gastric cancer: a multicenter retrospective study in Japan

[Background] Accelerated tumor growth during immunotherapy in pre-existing measurable lesions, hyperprogressive disease (HPD), has been reported. However, progression of non-measurable lesions and new lesions are frequently observed in patients with advanced gastric cancer (AGC). [Methods] This retrospective study involved AGC patients at 24 Japanese institutions who had measurable lesions and received nivolumab after ≥ 2 lines of chemotherapy. HPD was defined as a ≥ two-fold increase in the tumor growth rate of measurable lesions. The pattern of disease progression was classified according to new lesions in different organs and ascites appeared/increase of ascites. [Results] Of 245 patients, 147 (60.0%) showed progressive disease (PD) as the best response and 41 (16.7%) showed HPD during nivolumab monotherapy. There was no significant difference in overall survival (OS) between patients with HPD and those with PD other than HPD (median OS 5.0 vs 4.8 months; hazard ratio [HR] 1.0, 95% confidence interval [CI] 0.6–1.5; p = 1.0). Fifty-three patients developed new lesions in different organs and 58 had appearance/increase of ascites; these patients showed shorter OS than those without each of these features (median OS 3.3 vs 7.1 months, HR 1.8, 95% CI 1.2–2.7, p = 0.0031 for new lesions, and 3.0 vs 7.8 months, HR 2.6, 95% CI 1.8–3.8, p < 0.0001 for ascites). Thirty-one patients who had both features showed the worst prognosis (median OS 2.6 months). [Conclusions] New lesions in different organs and appearance/increase of ascites, rather than the original definition of HPD, are the patterns of disease progression associated with poor prognosis in AGC patients receiving nivolumab whose best response was PD

Impact of Dual Lipid-Lowering Strategy With Ezetimibe and Atorvastatin on Coronary Plaque Regression in Patients With Percutaneous Coronary Intervention The Multicenter Randomized Controlled PRECISE-IVUS Trial

AbstractBackgroundDespite standard statin therapy, a majority of patients retain a high “residual risk” of cardiovascular events.ObjectivesThe aim of this study was to evaluate the effects of ezetimibe plus atorvastatin versus atorvastatin monotherapy on the lipid profile and coronary atherosclerosis in Japanese patients who underwent percutaneous coronary intervention (PCI).MethodsThis trial was a prospective, randomized, controlled, multicenter study. Eligible patients who underwent PCI were randomly assigned to atorvastatin alone or atorvastatin plus ezetimibe (10 mg) daily. Atorvastatin was uptitrated with a treatment goal of low-density lipoprotein cholesterol (LDL-C) <70 mg/dl. Serial volumetric intravascular ultrasound was performed at baseline and again at 9 to 12 months to quantify the coronary plaque response in 202 patients.ResultsThe combination of atorvastatin/ezetimibe resulted in lower levels of LDL-C than atorvastatin monotherapy (63.2 ± 16.3 mg/dl vs. 73.3 ± 20.3 mg/dl; p < 0.001). For the absolute change in percent atheroma volume (PAV), the mean difference between the 2 groups (–1.538%; 95% confidence interval [CI]: –3.079% to 0.003%) did not exceed the pre-defined noninferiority margin of 3%, but the absolute change in PAV did show superiority for the dual lipid-lowering strategy (–1.4%; 95% CI: –3.4% to –0.1% vs. –0.3%; 95% CI: –1.9% to 0.9% with atorvastatin alone; p = 0.001). For PAV, a significantly greater percentage of patients who received atorvastatin/ezetimibe showed coronary plaque regression (78% vs. 58%; p = 0.004). Both strategies had acceptable side effect profiles, with a low incidence of laboratory abnormalities and cardiovascular events.ConclusionsCompared with standard statin monotherapy, the combination of statin plus ezetimibe showed greater coronary plaque regression, which might be attributed to cholesterol absorption inhibition–induced aggressive lipid lowering. (Plaque Regression With Cholesterol Absorption Inhibitor or Synthesis Inhibitor Evaluated by Intravascular Ultrasound [PRECISE-IVUS]; NCT01043380