Association between RUNX3 promoter methylation and gastric cancer: a meta-analysis

<p>Abstract</p> <p>Background</p> <p>Runt-related transcription factor 3 (RUNX3) is a member of the runt-domain family of transcription factors and has been reported to be a candidate tumor suppressor in gastric cancer. However, the association between RUNX3 promoter methylation and gastric cancer remains unclear.</p> <p>Methods</p> <p>We systematically reviewed studies of RUNX3 promoter methylation and gastric cancer published in English or Chinese from January 2000 to January 2011, and quantified the association between RUNX3 promoter methylation and gastric cancer using meta-analysis methods.</p> <p>Results</p> <p>A total of 1740 samples in 974 participants from seventeen studies were included in the meta-analysis. A significant association was observed between RUNX3 promoter methylation and gastric cancer, with an aggregated odds ratio (OR) of 5.63 (95%CI 3.15, 10.07). There was obvious heterogeneity among studies. Subgroup analyses (including by tissue origin, country and age), meta-regression were performed to determine the source of the heterogeneity. Meta-regression showed that the trend in ORs was inversely correlated with age. No publication bias was detected. The ORs for RUNX3 methylation in well-differentiated <it>vs </it>undifferentiated gastric cancers, and in intestinal-type <it>vs </it>diffuse-type carcinomas were 0.59 (95%CI: 0.30, 1.16) and 2.62 (95%CI: 1.33, 5.14), respectively. There were no significant differences in RUNX3 methylation in cancer tissues in relation to age, gender, TNM stage, invasion of tumors into blood vessel or lymphatic ducts, or tumor stage.</p> <p>Conclusions</p> <p>This meta-analysis identified a strong association between methylation of the RUNX3 promoter and gastric cancer, confirming the role of RUNX3 as a tumor suppressor gene.</p

Hyperoxemia and excess oxygen use in early acute respiratory distress syndrome : Insights from the LUNG SAFE study

Publisher Copyright: © 2020 The Author(s). Copyright: Copyright 2020 Elsevier B.V., All rights reserved.Background: Concerns exist regarding the prevalence and impact of unnecessary oxygen use in patients with acute respiratory distress syndrome (ARDS). We examined this issue in patients with ARDS enrolled in the Large observational study to UNderstand the Global impact of Severe Acute respiratory FailurE (LUNG SAFE) study. Methods: In this secondary analysis of the LUNG SAFE study, we wished to determine the prevalence and the outcomes associated with hyperoxemia on day 1, sustained hyperoxemia, and excessive oxygen use in patients with early ARDS. Patients who fulfilled criteria of ARDS on day 1 and day 2 of acute hypoxemic respiratory failure were categorized based on the presence of hyperoxemia (PaO2 > 100 mmHg) on day 1, sustained (i.e., present on day 1 and day 2) hyperoxemia, or excessive oxygen use (FIO2 ≥ 0.60 during hyperoxemia). Results: Of 2005 patients that met the inclusion criteria, 131 (6.5%) were hypoxemic (PaO2 < 55 mmHg), 607 (30%) had hyperoxemia on day 1, and 250 (12%) had sustained hyperoxemia. Excess FIO2 use occurred in 400 (66%) out of 607 patients with hyperoxemia. Excess FIO2 use decreased from day 1 to day 2 of ARDS, with most hyperoxemic patients on day 2 receiving relatively low FIO2. Multivariate analyses found no independent relationship between day 1 hyperoxemia, sustained hyperoxemia, or excess FIO2 use and adverse clinical outcomes. Mortality was 42% in patients with excess FIO2 use, compared to 39% in a propensity-matched sample of normoxemic (PaO2 55-100 mmHg) patients (P = 0.47). Conclusions: Hyperoxemia and excess oxygen use are both prevalent in early ARDS but are most often non-sustained. No relationship was found between hyperoxemia or excessive oxygen use and patient outcome in this cohort. Trial registration: LUNG-SAFE is registered with ClinicalTrials.gov, NCT02010073publishersversionPeer reviewe

Ice core O2 clumped isotope data from the Last Glacial Maximum measured in West Divide ice core WDC06A

Laboratory O2 clumped-isotope data (as D36 values measured at Rice University) for air occluded in ice core WDC06A spanning gas ages of 18000-21000 ky BP for the Last Glacial Maximum (LGM). Modeled atmospheric history for the LGM via outputs of the GISS-E2.1 driven and Data Assimilation (DAv2.0) driven chemical transport model incorporated into a 2-box model of the atmosphere

Ice core O2 clumped isotope data from the Last Glacial Maximum measured in Greenland Ice Sheet Project (GISP2-D) ice core

Laboratory O2 clumped-isotope data (as D36 values measured at Rice University) for air occluded in ice core GISP2-D spanning gas ages of 18000-21000 ky BP for the Last Glacial Maximum (LGM). Modeled atmospheric history for the LGM via outputs of the GISS-E2.1 driven and Data Assimilation (DAv2.0) driven chemical transport model incorporated into a 2-box model of the atmosphere

Effects of Ozone Isotopologue Formation on the Clumped‐Isotope Composition of Atmospheric O2

Tropospheric 18O18O is an emerging proxy for past tropospheric ozone and free‐tropospheric temperatures. The basis of these applications is the idea that isotope‐exchange reactions in the atmosphere drive 18O18O abundances toward isotopic equilibrium. However, previous work used an offline box‐model framework to explain the 18O18O budget, approximating the interplay of atmospheric chemistry and transport. This approach, while convenient, has poorly characterized uncertainties. To investigate these uncertainties, and to broaden the applicability of the 18O18O proxy, we developed a scheme to simulate atmospheric 18O18O abundances (quantified as ∆36 values) online within the GEOS‐Chem chemical transport model. These results are compared to both new and previously published atmospheric observations from the surface to 33 km. Simulations using a simplified O2 isotopic equilibration scheme within GEOS‐Chem show quantitative agreement with measurements only in the middle stratosphere; modeled ∆36 values are too high elsewhere. Investigations using a comprehensive model of the O‐O2‐O3 isotopic photochemical system and proof‐of‐principle experiments suggest that the simple equilibration scheme omits an important pressure dependence to ∆36 values: the anomalously efficient titration of 18O18O to form ozone. Incorporating these effects into the online ∆36 calculation scheme in GEOS‐Chem yields quantitative agreement for all available observations. While this previously unidentified bias affects the atmospheric budget of 18O18O in O2, the modeled change in the mean tropospheric ∆36 value since 1850 CE is only slightly altered; it is still quantitatively consistent with the ice‐core ∆36 record, implying that the tropospheric ozone burden increased less than 40% over the twentieth century. Plain Language Summary Oxygen in the air is constantly being broken apart and remade. Its constituent atoms are shuffled around by light‐induced chemical reactions, which cause changes in the number of heavy oxygen atoms that are bound together. The number of these heavy‐atom “clumps” is sensitive to air temperatures and the presence of air pollution; hence, their variations are being used to understand past high‐altitude temperatures and atmospheric chemistry. This study incorporates oxygen clumping into an atmospheric chemistry model and compares the results to measurements of oxygen clumping in the atmosphere. We find that the model can explain all the modern‐day measurements (from the surface to 33 km altitude), but only if the broader fates of oxygen atoms–that is, their incorporation into other molecules beyond O2–are considered. Simulations of the preindustrial atmosphere are also generally consistent with snapshots of the ancient atmosphere obtained from O2 trapped in ice cores. The developments described herein will thus enable models to simulate heavy oxygen‐atom clumping in past cold and warm climates and enable simulated high‐altitude atmospheric changes to be evaluated directly against ice‐core snapshots of the ancient atmosphere. Key Points Online calculations of atmospheric 18O18O variations have been implemented in GEOS‐Chem, which reproduces all atmospheric observations well Titration of 18O18O into heavy ozone was determined to be an important missing component of previous 18O18O budgets Change in atmospheric 18O18O abundance since 1850 CE is still consistent with <40% increase in tropospheric ozone burde

Effect of biomass burning on black carbon (BC) in South Asia and Tibetan Plateau: The analysis of WRF-Chem modeling

The focus of this study is to evaluate the impact of biomass burning (BB) from South Asia and Southeast Asia on the glaciers over the Tibetan Plateau. The seasonality and long-term trend of biomass fires measured by Terra and Aqua satellite data from 2010 to 2016 are used in this study. The analysis shows that the biomass burnings were widely dispersed in the continental of Indian and Southeast Asia and existed a strong seasonal variation. The biomass burnings in winter (January) were relatively weak and scattered and were significantly enhanced in spring (April). The highest biomass burnings located in two regions. One was along the foothill of Himalayas, where is a dense population area, and the second located in Southeast Asia. Because these two high biomass burning regions are close to the Tibetan Plateau, they could have important effects on the BC deposition over the glaciers of the Tibetan Plateau. In order to study the effect of BB emissions on the deposition over the glaciers in the Tibetan Plateau, a regional chemical model (WRF-Chem; Weather Research and Forecasting Chemical model) was applied to simulate the BC distributions and the transport from BB emission regions to the glaciers in Tibetan Plateau. The result shows that in winter (January), due to the relatively weak BB emissions, the effect of BB emissions on BC concentrations was not significant. The BC concentrations resulted from BB emissions ranged from 0.1 to 2.0 &mu;g/m3, with high concentrations distributed along the foothill of Himalayas and the southeastern Asia region. Due to the relative low BC concentrations, there was insignificant effect of BB emissions on the deposition over the glaciers in the Tibetan Plateau in winter. However, the BB emissions were highest in spring (April), producing high BC concentrations. For example, along the Himalayas Mountain and in the southeastern Asia region, The BC concentrations ranged from 2.0 to 6.0 &mu;g/m3. In addition to the high BC concentrations, there were also west and south prevailing winds in these regions. As a result, the BC particles were transported to the glaciers in the Tibetan Plateau, causing significant deposition of BC particles on the snow surface of the glaciers. This study suggests that the biomass burning emissions have important effects on the BC deposition over the glaciers in the Tibetan Plateau, and the contaminations of glaciers could have significant impact on the melting of snow in the Tibetan Plateau, causing some severe environmental problems, such as the water resources.</p

Seasonal variation and four-year trend of black carbon in the Midwest China: The analysis of the ambient measurement and WRF-Chemmodeling

In-situ measurement of black carbon (BC) concentration from September 2003 to August 2007 in the Xi'an City at the Guanzhong Basin located in the mid-western China (the Guanzhong Basin) was analyzed. A regional dynamics and aerosol model (WRF-Chem) was used to quantify the impacts of local emission, meteorological conditions, and regional atmospheric transport on seasonal variation of BC concentration at the Guanzhong Basin. The results show that the regional prevailing winds at the Guanzhong Basin were unfavorable for the horizontal transport. The mean wind speeds ranged from 1.0 m/s to 1.9 m/s. During winter, the wind at the Guanzhong Basin was very weak (∼1.0 m/s). During spring and autumn, there was a wind convergent zone at the Guanzhong Basin, constraining the BC concentrations inside the Guanzhong Basin. As a result, the BC concentrations were persistently high at the Guanzhong Basin. In addition to the high background concentrations, there was a strong seasonal variation, with a maximum in winter (winter maximum) and a minimum in summer (summer minimum), with the maximum of the mean concentration of 30 μg m−3 in 2003–2004 winter, and the minimum of 5 μg m−3 in 2004 summer. The model sensitivity study shows that the seasonal variation of BC concentration was largely due to the seasonal variation of BC emission, especially during winter with the maximum of BC emission. A strong annual decrease trend of the BC concentration was found from 2004 to 2007. It is interesting to note that the decrease of the BC concentration only occurred in winter. For example, the winter maximum was 20 μg m−3 in 2003, and reduced to 11 μg m−3 in 2006, with about 50% decrease. In contrast, the summer minimum was 10 μg m−3 in 2004 and 9 μg m−3 in 2007, with only 10% decrease. This study suggests that the rapid decrease in the winter maximum was mainly due to the reduction of the BC emission in winter, implying the effective winter emission control at the Guanzhong Basin